110 results on '"WEN-MEI FU"'
Search Results
2. Impairment of social behaviors in Arhgef10 knockout mice
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Dai-Hua Lu, Hsiao-Mei Liao, Chia-Hsiang Chen, Huang-Ju Tu, Houng-Chi Liou, Susan Shur-Fen Gau, and Wen-Mei Fu
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ARHGEF10 ,Autism spectrum disorder ,Social deficits ,Serotonin ,Norepinephrine ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Impaired social interaction is one of the essential features of autism spectrum disorder (ASD). Our previous copy number variation (CNV) study discovered a novel deleted region associated with ASD. One of the genes included in the deleted region is ARHGEF10. A missense mutation of ARHGEF10 has been reported to be one of the contributing factors in several diseases of the central nervous system. However, the relationship between the loss of ARHGEF10 and the clinical symptoms of ASD is unclear. Methods We generated Arhgef10 knockout mice as a model of ASD and characterized the social behavior and the biochemical changes in the brains of the knockout mice. Results Compared with their wild-type littermates, the Arhgef10-depleted mice showed social interaction impairment, hyperactivity, and decreased depression-like and anxiety-like behavior. Behavioral measures of learning in the Morris water maze were not affected by Arhgef10 deficiency. Moreover, neurotransmitters including serotonin, norepinephrine, and dopamine were significantly increased in different brain regions of the Arhgef10 knockout mice. In addition, monoamine oxidase A (MAO-A) decreased in several brain regions. Conclusions These results suggest that ARHGEF10 is a candidate risk gene for ASD and that the Arhgef10 knockout model could be a tool for studying the mechanisms of neurotransmission in ASD. Trial registration Animal studies were approved by the Institutional Animal Care and Use Committee of National Taiwan University (IACUC 20150023). Registered 1 August 2015.
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- 2018
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3. Drug candidates in clinical trials for Alzheimer’s disease
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Shih-Ya Hung and Wen-Mei Fu
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Alzheimer’s disease ,Clinical trials ,Drug treatment ,Neurodegenerative disease ,Medicine - Abstract
Abstract Alzheimer’s disease (AD) is a major form of senile dementia, characterized by progressive memory and neuronal loss combined with cognitive impairment. AD is the most common neurodegenerative disease worldwide, affecting one-fifth of those aged over 85 years. Recent therapeutic approaches have been strongly influenced by five neuropathological hallmarks of AD: acetylcholine deficiency, glutamate excitotoxicity, extracellular deposition of amyloid-β (Aβ plague), formation of intraneuronal neurofibrillary tangles (NTFs), and neuroinflammation. The lowered concentrations of acetylcholine (ACh) in AD result in a progressive and significant loss of cognitive and behavioral function. Current AD medications, memantine and acetylcholinesterase inhibitors (AChEIs) alleviate some of these symptoms by enhancing cholinergic signaling, but they are not curative. Since 2003, no new drugs have been approved for the treatment of AD. This article focuses on the current research in clinical trials targeting the neuropathological findings of AD including acetylcholine response, glutamate transmission, Aβ clearance, tau protein deposits, and neuroinflammation. These investigations include acetylcholinesterase inhibitors, agonists and antagonists of neurotransmitter receptors, β-secretase (BACE) or γ-secretase inhibitors, vaccines or antibodies targeting Aβ clearance or tau protein, as well as anti-inflammation compounds. Ongoing Phase III clinical trials via passive immunotherapy against Aβ peptides (crenezumab, gantenerumab, and aducanumab) seem to be promising. Using small molecules blocking 5-HT6 serotonin receptor (intepirdine), inhibiting BACE activity (E2609, AZD3293, and verubecestat), or reducing tau aggregation (TRx0237) are also currently in Phase III clinical trials. We here systemically review the findings from recent clinical trials to provide a comprehensive review of novel therapeutic compounds in the treatment and prevention of AD.
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- 2017
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4. Antagonism of proteasome inhibitor-induced heme oxygenase-1 expression by PINK1 mutation.
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Xiang-Jun Sheng, Hunag-Ju Tu, Wei-Lin Chien, Kai-Hsiang Kang, Dai-Hua Lu, Horng-Huei Liou, Ming-Jen Lee, and Wen-Mei Fu
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Medicine ,Science - Abstract
PTEN-induced putative kinase 1 (PINK1) is an integral protein in the mitochondrial membrane and maintains mitochondrial fidelity. Pathogenic mutations in PINK1 have been identified as a cause of early-onset autosomal recessive familial Parkinson's disease (PD). The ubiquitin proteasome pathway is associated with neurodegenerative diseases. In this study, we investigated whether mutations of PINK1 affects the cellular stress response following proteasome inhibition. Administration of MG132, a peptide aldehyde proteasome inhibitor, significantly increased the expression of heme oxygenase-1 (HO-1) in rat dopaminergic neurons in the substantia nigra and in the SH-SY5Y neuronal cell line. The induction of HO-1 expression by proteasome inhibition was reduced in PINK1 G309D mutant cells. MG132 increased the levels of HO-1 through the Akt, p38, and Nrf2 signaling pathways. Compared with the cells expressing WT-PINK1, the phosphorylation of Akt and p38 was lower in those cells expressing the PINK1 G309D mutant, which resulted in the inhibition of the nuclear translocation of Nrf2. Furthermore, MG132-induced neuronal death was enhanced by the PINK1 G309D mutation. In this study, we demonstrated that the G309D mutation impairs the neuroprotective function of PINK1 following proteasome inhibition, which may be related to the pathogenesis of PD.
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- 2017
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5. Hyperactivity and Impulsivity in Children with Untreated Allergic Rhinitis: Corroborated by Rating Scale and Continuous Performance Test
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Ming-Tao Yang, Wang-Tso Lee, Jao-Shwann Liang, Yu-Ju Lin, Wen-Mei Fu, and Chia-Chun Chen
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allergic rhinitis ,attention deficit hyperactivity disorder ,continuous performance test ,Pediatrics ,RJ1-570 - Abstract
Allergic rhinitis (AR) is the most common chronic allergic disease in school-age children. An increased prevalence of attention deficit hyperactivity disorder (ADHD) in AR patients has been reported; however, inattention and hyperactivity in AR children have not been investigated using objective and scientific measurements. Methods: We used AR symptom score, ADHD symptom scale, and computerized continuous performance test (CPT) to study the attention and impulsivity in AR children, age-matched controls, and ADHD children (aged 6–15 years). Univariate and multivariate linear regression analyses were applied to identify risk factors for impulsivity and inattention in AR children. Results: Twenty-nine controls, 10 ADHD, and 105 AR children were enrolled. There were no differences in age and sex among the three groups. The scores of Hyperactivity/Impulsivity subscales of ADHD symptoms from both parents and teachers were significantly higher in the AR children. The CPT in AR children revealed higher commission errors, shorter reaction times, and more perseveration. Risk factors for inattention and impulsivity in AR children included younger age, male sex, higher AR symptom scores, persistent AR, moderate/severe AR, multiple atopic diseases, family history of atopy, and possible comorbidity with ADHD. Conclusion: Care for AR children should not only involve treating their allergy, but also monitoring the possible comorbidities of impulsivity and inattention. In children with impulsivity, AR should be considered in addition to ADHD.
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- 2014
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6. Metabolomic Dynamic Analysis of Hypoxia in MDA-MB-231 and the Comparison with Inferred Metabolites from Transcriptomics Data
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Yufeng Jane Tseng, Wen-Mei Fu, Ching-Hua Kuo, San-Yuan Wang, Yeu-Chern Harn, Tsung-Jung Ho, I-Lin Tsai, and Tien-Chueh Kuo
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1H-NMR spectroscopy ,metabolic network ,metabolomics ,multivariate analysis ,tumor hypoxia ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Hypoxia affects the tumor microenvironment and is considered important to metastasis progression and therapy resistance. Thus far, the majority of global analyses of tumor hypoxia responses have been limited to just a single omics level. Combining multiple omics data can broaden our understanding of tumor hypoxia. Here, we investigate the temporal change of the metabolite composition with gene expression data from literature to provide a more comprehensive insight into the system level in response to hypoxia. Nuclear magnetic resonance spectroscopy was used to perform metabolomic profiling on the MDA-MB-231 breast cancer cell line under hypoxic conditions. Multivariate statistical analysis revealed that the metabolic difference between hypoxia and normoxia was similar over 24 h, but became distinct over 48 h. Time dependent microarray data from the same cell line in the literature displayed different gene expressions under hypoxic and normoxic conditions mostly at 12 h or earlier. The direct metabolomic profiles show a large overlap with theoretical metabolic profiles deduced from previous transcriptomic studies. Consistent pathways are glycolysis/gluconeogenesis, pyruvate, purine and arginine and proline metabolism. Ten metabolic pathways revealed by metabolomics were not covered by the downstream of the known transcriptomic profiles, suggesting new metabolic phenotypes. These results confirm previous transcriptomics understanding and expand the knowledge from existing models on correlation and co-regulation between transcriptomic and metabolomics profiles, which demonstrates the power of integrated omics analysis.
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- 2013
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7. Microglia-Derived Cytokines/Chemokines Are Involved in the Enhancement of LPS-Induced Loss of Nigrostriatal Dopaminergic Neurons in DJ-1 Knockout Mice.
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Chia-Hung Chien, Ming-Jen Lee, Houng-Chi Liou, Horng-Huei Liou, and Wen-Mei Fu
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Medicine ,Science - Abstract
Mutation of DJ-1 (PARK7) has been linked to the development of early-onset Parkinson's disease (PD). However, the underlying molecular mechanism is still unclear. This study is aimed to compare the sensitivity of nigrostriatal dopaminergic neurons to lipopolysaccharide (LPS) challenge between DJ-1 knockout (KO) and wild-type (WT) mice, and explore the underlying cellular and molecular mechanisms. Our results found that the basal levels of interferon (IFN)-γ (the hub cytokine) and interferon-inducible T-cell alpha chemoattractant (I-TAC) (a downstream mediator) were elevated in the substantia nigra of DJ-1 KO mice and in microglia cells with DJ-1 deficiency, and the release of cytokine/chemokine was greatly enhanced following LPS administration in the DJ-1 deficient conditions. In addition, direct intranigral LPS challenge caused a greater loss of nigrostriatal dopaminergic neurons and striatal dopamine content in DJ-1 KO mice than in WT mice. Furthermore, the sensitization of microglia cells to LPS challenge to release IFN-γ and I-TAC was via the enhancement of NF-κB signaling, which was antagonized by NF-κB inhibitors. LPS-induced increase in neuronal death in the neuron-glia co-culture was enhanced by DJ-1 deficiency in microglia, which was antagonized by the neutralizing antibodies against IFN-γ or I-TAC. These results indicate that DJ-1 deficiency sensitizes microglia cells to release IFN-γ and I-TAC and causes inflammatory damage to dopaminergic neurons. The interaction between the genetic defect (i.e. DJ-1) and inflammatory factors (e.g. LPS) may contribute to the development of PD.
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- 2016
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8. Hypoxic Preconditioning Suppresses Glial Activation and Neuroinflammation in Neonatal Brain Insults
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Chien-Yi Chen, Wei-Zen Sun, Kai-Hsiang Kang, Hung-Chieh Chou, Po-Nien Tsao, Wu-Shiun Hsieh, and Wen-Mei Fu
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Pathology ,RB1-214 - Abstract
Perinatal insults and subsequent neuroinflammation are the major mechanisms of neonatal brain injury, but there have been only scarce reports on the associations between hypoxic preconditioning and glial activation. Here we use neonatal hypoxia-ischemia brain injury model in 7-day-old rats and in vitro hypoxia model with primary mixed glial culture and the BV-2 microglial cell line to assess the effects of hypoxia and hypoxic preconditioning on glial activation. Hypoxia-ischemia brain insult induced significant brain weight reduction, profound cell loss, and reactive gliosis in the damaged hemisphere. Hypoxic preconditioning significantly attenuated glial activation and resulted in robust neuroprotection. As early as 2 h after the hypoxia-ischemia insult, proinflammatory gene upregulation was suppressed in the hypoxic preconditioning group. In vitro experiments showed that exposure to 0.5% oxygen for 4 h induced a glial inflammatory response. Exposure to brief hypoxia (0.5 h) 24 h before the hypoxic insult significantly ameliorated this response. In conclusion, hypoxic preconditioning confers strong neuroprotection, possibly through suppression of glial activation and subsequent inflammatory responses after hypoxia-ischemia insults in neonatal rats. This might therefore be a promising therapeutic approach for rescuing neonatal brain injury.
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- 2015
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9. Local immunosuppressive microenvironment enhances migration of melanoma cells to lungs in DJ-1 knockout mice.
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Chia-Hung Chien, Ming-Jen Lee, Houng-Chi Liou, Horng-Huei Liou, and Wen-Mei Fu
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Medicine ,Science - Abstract
DJ-1 is an oncoprotein that promotes survival of cancer cells through anti-apoptosis. However, DJ-1 also plays a role in regulating IL-1β expression, and whether inflammatory microenvironment built by dysregulated DJ-1 affects cancer progression is still unclear. This study thus aimed to compare the metastatic abilities of melanoma cells in wild-type (WT) and DJ-1 knockout (KO) mice, and to check whether inflammatory microenvironment built in DJ-1 KO mice plays a role in migration of cancer cells to lungs. First, B16F10 melanoma cells (at 6 × 10(4)) were injected into the femoral vein of mice, and formation of lung nodules, levels of lung IL-1β and serum cytokines, and accumulation of myeloid-derived suppressor cells (MDSCs) were compared between WT and DJ-1 KO mice. Second, the cancer-bearing mice were treated with an interleukin-1 beta (IL-1β) neutralizing antibody to see whether IL-1β is involved in the cancer migration. Finally, cultured RAW 264.7 macrophage and B16F10 melanoma cells were respectively treated with DJ-1 shRNA and recombinant IL-1β to explore underlying molecular mechanisms. Our results showed that IL-1β enhanced survival and colony formation of cultured melanoma cells, and that IL-1β levels were elevated both in DJ-1 KO mice and in cultured macrophage cells with DJ-1 knockdown. The elevated IL-1β correlated with higher accumulation of immunosuppressive MDSCs and formation of melanoma module in the lung of DJ-1 KO mice, and both can be decreased by treating mice with IL-1β neutralizing antibodies. Taken together, these results indicate that immunosuppressive tissue microenvironment built in DJ-1 KO mice can enhance lung migration of cancer, and IL-1β plays an important role in promoting the cancer migration.
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- 2015
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10. Targeted delivery of erythropoietin by transcranial focused ultrasound for neuroprotection against ischemia/reperfusion-induced neuronal injury: a long-term and short-term study.
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Sheng-Kai Wu, Ming-Tao Yang, Kai-Hsiang Kang, Houng-Chi Liou, Dai-Hua Lu, Wen-Mei Fu, and Win-Li Lin
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Medicine ,Science - Abstract
Erythropoietin (EPO) is a neuroprotective agent against cerebral ischemia/reperfusion (I/R)-induced brain injury. However, its crossing of blood-brain barrier is limited. Focused ultrasound (FUS) sonication with microbubbles (MBs) can effectively open blood-brain barrier to boost the vascular permeability. In this study, we investigated the effects of MBs/FUS on extending the therapeutic time window of EPO and its neuroprotective effects in both acute and chronic phases. Male Wistar rats were firstly subjected to two common carotid arteries and right middle cerebral artery occlusion (three vessels occlusion, 3VO) for 50 min, and then the rats were treated with hEPO (human recombinant EPO, 5000 IU/kg) with or without MBs/FUS at 5 h after occlusion/reperfusion. Acute phase investigation (I/R, I/R+MBs/FUS, I/R+hEPO, and I/R+hEPO+MBs/FUS) was performed 24 h after I/R; chronic tests including cylinder test and gait analysis were performed one month after I/R. The experimental results showed that MBs/FUS significantly increased the cerebral content of EPO by bettering vascular permeability. In acute phase, both significant improvement of neurological score and reduction of infarct volume were found in the I/R+hEPO+MBs/FUS group, as compared with I/R and I/R+hEPO groups. In chronic phase, long-term behavioral recovery and neuronal loss in brain cortex after I/R injury was significantly improved in the I/R+hEPO+MBs/FUS group. This study indicates that hEPO administration with MBs/FUS sonication even at 5 h after occlusion/reperfusion can produce a significant neuroprotection.
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- 2014
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11. Osteopontin upregulates the expression of glucose transporters in osteosarcoma cells.
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I-Shan Hsieh, Rong-Sen Yang, and Wen-Mei Fu
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Medicine ,Science - Abstract
Osteosarcoma is the most common primary malignancy of bone. Even after the traditional standard surgical therapy, metastasis still occurs in a high percentage of patients. Glucose is an important source of metabolic energy for tumor proliferation and survival. Tumors usually overexpress glucose transporters, especially hypoxia-responsive glucose transporter 1 and glucose transporter 3. Osteopontin, hypoxia-responsive glucose transporter 1, and glucose transporter 3 are overexpressed in many types of tumors and have been linked to tumorigenesis and metastasis. In this study, we investigated the regulation of glucose transporters by osteopontin in osteosarcoma. We observed that both glucose transporters and osteopontin were upregulated in hypoxic human osteosarcoma cells. Endogenously released osteopontin regulated the expression of glucose transporter 1 and glucose transporter 3 in osteosarcoma and enhanced glucose uptake into cells via the αvβ3 integrin. Knockdown of osteopontin induced cell death in 20% of osteosarcoma cells. Phloretin, a glucose transporter inhibitor, also caused cell death by treatment alone. The phloretin-induced cell death was significantly enhanced in osteopontin knockdown osteosarcoma cells. Combination of a low dose of phloretin and chemotherapeutic drugs, such as daunomycin, 5-Fu, etoposide, and methotrexate, exhibited synergistic cytotoxic effects in three osteosarcoma cell lines. Inhibition of glucose transporters markedly potentiated the apoptotic sensitivity of chemotherapeutic drugs in osteosarcoma. These results indicate that the combination of a low dose of a glucose transporter inhibitor with cytotoxic drugs may be beneficial for treating osteosarcoma patients.
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- 2014
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12. 5-Lipoxygenase inhibitors attenuate TNF-α-induced inflammation in human synovial fibroblasts.
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Han-Ching Lin, Tzu-Hung Lin, Ming-Yueh Wu, Yung-Cheng Chiu, Chih-Hsin Tang, Mann-Jen Hour, Houng-Chi Liou, Huang-Ju Tu, Rong-Sen Yang, and Wen-Mei Fu
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Medicine ,Science - Abstract
The lipoxygenase isoform of 5-lipoxygenase (5-LOX) is reported to be overexpressed in human rheumatoid arthritis synovial tissue and involved in the progress of inflammatory arthritis. However, the detailed mechanism of how 5-lipoxygenase regulates the inflammatory response in arthritis synovial tissue is still unclear. The aim of this study was to investigate the involvement of lipoxygenase pathways in TNF-α-induced production of cytokines and chemokines. Human synovial fibroblasts from rheumatoid patients were used in this study. 5-LOX inhibitors and shRNA were used to examine the involvement of 5-LOX in TNF-α-induced cytokines and chemokines expression. The signaling pathways were examined by Western Blotting or immunofluorescence staining. The effect of 5-LOX inhibitor on TNF-α-induced chemokine expression and paw edema was also explored in vivo in C57BL/6 mice. Treatment with 5-LOX inhibitors significantly decreased TNF-α-induced pro-inflammatory mediators including interleukin-6 (IL-6) and monocyte chemo-attractant protein-1 (MCP-1) in human synovial fibroblasts. Knockdown of 5-LOX using shRNA exerted similar inhibitory effects. The abrogation of NF-κB activation was involved in the antagonizing effects of these inhibitors. Furthermore, 5-LOX inhibitor decreased TNF-α-induced up-regulation of serum MCP-1 level and paw edema in mouse model. Our results provide the evidence that the administration of 5-LOX inhibitors is able to ameliorate TNF-α-induced cytokine/chemokine release and paw edema, indicating that 5-LOX inhibitors may be developed for therapeutic treatment of inflammatory arthritis.
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- 2014
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13. Cytokine MIF Enhances Blood-Brain Barrier Permeability: Impact for Therapy in Ischemic Stroke
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Horng-Huei Liou, Kai-Hsiang Kang, Jiann-Shing Jeng, Yu Chuan Liu, Yung Hsu Tsai, Wen-Mei Fu, Houng Chi Liou, and Sung-Chun Tang
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0301 basic medicine ,medicine.medical_treatment ,animal diseases ,lcsh:Medicine ,Pharmacology ,Blood–brain barrier ,Neuroprotection ,Article ,Permeability ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,In vivo ,medicine ,Animals ,Humans ,cardiovascular diseases ,lcsh:Science ,Stroke ,Macrophage Migration-Inhibitory Factors ,Cells, Cultured ,Neurons ,Multidisciplinary ,Tight junction ,business.industry ,lcsh:R ,Antagonist ,Endothelial Cells ,medicine.disease ,Rats ,Intramolecular Oxidoreductases ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Cytokine ,Blood-Brain Barrier ,lcsh:Q ,business ,030217 neurology & neurosurgery - Abstract
Ischemic stroke is a devastating disease with limited therapeutic options. It is very urgent to find a new target for drug development. Here we found that the blood level of MIF in ischemic stroke patients is upregulated. To figure out the pathological role of MIF in ischemic stroke, both in vitro and in vivo studies were conducted. For in vitro studies, primary cortical neuron cultures and adult rat brain endothelial cells (ARBECs) were subjected to oxygen-glucose deprivation (OGD)/reoxygenation. Middle cerebral artery occlusion (MCAo) rodent models were used for in vivo studies. The results show that MIF exerts no direct neuronal toxicity in primary culture but disrupts tight junction in ARBECs. Furthermore, administration of MIF following MCAo shows the deleterious influence on stroke-induced injury by destroying the tight junction of blood-brain barrier and increasing the infarct size. In contrast, administration of MIF antagonist ISO-1 has the profound neuroprotective effect. Our results demonstrate that MIF might be a good drug target for the therapy of stroke.
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- 2018
14. Corrigendum to 'Pulsed-wave low-dose ultrasound hyperthermia selectively enhances nanodrug delivery and improves antitumor efficacy for brain metastasis of breast cancer' [Ultrason. Sonochem. 36 (2017) 198–205]
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Win-Li Lin, Chi-Feng Chiang, Sheng-Kai Wu, Houng-Chi Liou, Wen-Mei Fu, and Yu-Hone Hsu
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Hyperthermia ,Acoustics and Ultrasonics ,business.industry ,Organic Chemistry ,Ultrasound ,Low dose ,Acoustics. Sound ,QC221-246 ,medicine.disease ,Inorganic Chemistry ,Chemistry ,Text mining ,Breast cancer ,medicine ,Cancer research ,Chemical Engineering (miscellaneous) ,Environmental Chemistry ,Radiology, Nuclear Medicine and imaging ,Pulsed wave ,business ,QD1-999 ,Brain metastasis - Published
- 2021
15. CXCL12/CXCR4 Signaling Contributes to the Pathogenesis of Opioid Tolerance
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Houng-Chi Liou, Chih-Peng Lin, Tzu-Hung Lin, Kai-Hsiang Kang, Wen-Mei Fu, Huang-Ju Tu, Ming-Yueh Wu, and Wei-Zen Sun
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Adult ,Male ,Drug ,Receptors, CXCR4 ,media_common.quotation_subject ,Analgesic ,Pharmacology ,Rats, Sprague-Dawley ,Translational Research, Biomedical ,03 medical and health sciences ,0302 clinical medicine ,030202 anesthesiology ,Drug tolerance ,medicine ,Animals ,Humans ,Prospective Studies ,Injections, Spinal ,Neuroinflammation ,Aged ,Pain Measurement ,media_common ,Morphine ,Mechanism (biology) ,business.industry ,Chronic pain ,Drug Tolerance ,Middle Aged ,medicine.disease ,Chemokine CXCL12 ,Rats ,Analgesics, Opioid ,Anesthesiology and Pain Medicine ,Opioid ,Case-Control Studies ,Female ,business ,Biomarkers ,030217 neurology & neurosurgery ,Signal Transduction ,medicine.drug - Abstract
Long-term opioid therapy for chronic pain may lead to analgesic tolerance, especially when administered intrathecally, thus preventing adequate pain relief. Discovering drug targets to treat opioid tolerance using a mechanism-based approach targeting opioid-induced neuroinflammation provides new therapeutic opportunities. In this study, we provide translational evidence that CXCL12/CXCR4 signaling contributes to the pathogenesis of opioid tolerance.The CXCL12 levels in the cerebrospinal fluid of opioid-tolerant patients were compared with those of opioid-naive subjects. For further investigation, a rodent translational study was designed using 2 clinically relevant opioid delivery paradigms: daily intraperitoneal morphine injections and continuous intrathecal morphine infusion. We measured rats' tail flick responses and calculated the percentage of maximum possible effects (%MPE) to demonstrate opioid acute antinociception and the development of analgesic tolerance. The effects of exogenous CXCL12, CXCL12 neutralizing antibody, and receptor antagonist AMD3100 were investigated by intrathecal administration. Data were presented as mean ± SEM.CXCL12 was significantly upregulated in the cerebrospinal fluid of opioid-tolerant patients for 892 ± 34 pg/mL (n = 27) versus 755 ± 33 pg/mL (n = 10) in naive control subjects (P = .03). Furthermore, after 2 and 5 days of intrathecal morphine infusion, rat lumbar spinal cord dorsal horn CXCL12 messenger RNA levels were significantly upregulated by 3.2 ± 0.7 (P = .016) and 3.4 ± 0.3 (P = .003) fold, respectively. Results from the daily intraperitoneal morphine injection experiments revealed that administering an intrathecal infusion of CXCL12 for 24 hours before the first morphine injection did not decrease antinociception efficacy on day 1 but accelerated tolerance after day 2 (%MPE 49.5% vs 88.1%, P = .0003). In the intrathecal morphine coinfusion experiments, CXCL12 accelerated tolerance development (%MPE 9.4% vs 43.4% on day 1, P.0001), whereas coadministration with CXCL12 neutralizing antibody attenuated tolerance (72.5% vs 43.4% on day 1, P.0001; 47.6% vs 17.5% on day 2, P.0001). Coadministration of receptor antagonist AMD 3100 can persistently preserve morphine analgesic effects throughout the study period (27.9% ± 4.1% vs 0.9% ± 1.6% on day 5, P = .03).The CXCL12/CXCR4 pathway contributes to the pathogenesis of opioid tolerance. Our study indicates that intervening with CXCL12/CXCR4 signaling has therapeutic potential for opioid tolerance.
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- 2017
16. Calcitonin gene-related peptide potentiates synaptic responses at developing neuromuscular junction
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Bai Lu, Wen-mei Fu, Greengard, Paul, and Mu-ming Pu
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Synapses -- Research ,Neural conduction -- Research ,Neuromuscular junction -- Research ,Environmental issues ,Science and technology ,Zoology and wildlife conservation - Abstract
Calcitonin gene-related peptide (CGRP), a neuropeptide in presynaptic motor nerve terminals, promotes postsynaptic reaction in maturing neuromuscular networks by extending the bursting period of embryonic ACh channels. The effect of CRGP on ACh channels is simulated by dibutyryl-cyclic AMP and cAMP-dependent protein kinase, obstructed by peptide inhibitor PKA. Postsynaptic inhibitions by PKA narrowed the amplitude and decay time of spontaneous synaptic current. Prolonging the burst duration raises postsynaptic activity at the bginning of the development stage, when time resolution is not too crucial.
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- 1993
17. Acquisition of tumorigenic potential and enhancement of angiogenesis in pulmonary stem/progenitor cells through Oct-4 hyperexpression
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Shu-Chun Teng, Cheng-Wen Wu, Yu-Chi Wang, Huei-Wen Chen, Chia Yu Kuo, Fu-Chuo Peng, Choa Chi Ho, Thai-Yen Ling, Wen-Mei Fu, Yung Kang Huang, Pan-Chyr Yang, and Sing Yi Gu
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Male ,0301 basic medicine ,Lung Neoplasms ,Carcinogenesis ,Angiogenesis ,Cellular differentiation ,Oct-4 ,Apoptosis ,Mice, SCID ,Adenocarcinoma ,Biology ,Regenerative medicine ,angiogenesis ,Mice ,03 medical and health sciences ,cancer initiating cells ,Cancer stem cell ,pulmonary stem/progenitor cells ,Biomarkers, Tumor ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,Progenitor cell ,Cell Proliferation ,Neovascularization, Pathologic ,Cancer ,Angiopoietins ,medicine.disease ,Xenograft Model Antitumor Assays ,030104 developmental biology ,Oncology ,Immunology ,Neoplastic Stem Cells ,Cancer research ,angiopoietins/Tie2 ,Octamer Transcription Factor-3 ,Research Paper - Abstract
// Sing-Yi Gu 1, 2 , Choa-Chi Ho 3 , Yung-Kang Huang 2 , Huei-Wen Chen 1 , Yu-Chi Wang 2 , Chia-Yu Kuo 2 , Shu-Chun Teng 4 , Wen-Mei Fu 2 , Pan-Chyr Yang 3 , Cheng-Wen Wu 5 , Fu-Chuo Peng 1 , Thai-Yen Ling 2, 6 1 Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan 2 Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan 3 Department of Internal Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan 4 Department of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan 5 Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan 6 Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan Correspondence to: Thai-Yen Ling, e-mail: tyling@ntu.edu.tw Fu-Chuo Peng, e-mail: fcpeng@ntu.edu.tw Keywords: pulmonary stem/progenitor cells, cancer initiating cells, Oct-4, angiogenesis, angiopoietins/Tie2 Received: November 01, 2015 Accepted: January 28, 2016 Published: February 9, 2016 ABSTRACT Cancer stem cells, also known as cancer initiating cells (CICs), are considered to be responsible for tumor growth and chemoresistance. Different hypotheses have been proposed to explain the origin of CICs, including mutations in adult stem/progenitor cells or the acquisition of stem-like characteristics in differentiated cells; however, studies have yielded conflicting identification for CICs and have little information for the origin to generate CICs. Part of the difficulty in identifying CICs may stem from the fact that the CICs studied have been largely derived from cancer cell lines or well-developed tumors. In previous studies, we have reported the enrichment of mouse pulmonary stem/progenitor cells (mPSCs) by using serum-free primary selection culture followed by FACS isolation using the coxsackievirus/adenovirus receptor (CAR) as the positive selection marker. Here, we demonstrated that overexpression of the pluripotent transcription factor Oct-4 is sufficient to induce CAR + /mPSCs transformation, which we name CAR + /mPSCs Oct-4_hi . These transformed cells possess cancer initiating and chemoresistance potential, as well as exhibiting remarkable expression of certain proangiogenic factors, including angiopoietins (ANGs) and VEGF, and enhanced angiogenic potential. Moreover, CAR + /mPSCs Oct-4_hi actively participated in tumor blood vessel formation and triggered a novel angiogenic mechanism, the angiopoietins/Tie2 signaling pathway. These study provide critical evidence supporting the possible origin to generate CICs, and help elucidate the pathways responsible for CICs-mediated blood vessel formation.
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- 2016
18. Erratum to 'Leukemia inhibitory factor (LIF) potentiates antinociception activity and inhibits tolerance induction of opioids' [Br J Anaesth 2016; 117: 512-520]
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S.Y. Ho, Kai-Hsiang Kang, Wen-Mei Fu, Chih-Peng Lin, Horng-Huei Liou, Huang-Ju Tu, and Houng-Chi Liou
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Tolerance induction ,Anesthesiology and Pain Medicine ,business.industry ,Medicine ,Pharmacology ,business ,Leukemia inhibitory factor - Published
- 2018
19. Impairment of social behaviors in Arhgef10 knockout mice
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Chia-Hsiang Chen, Susan Shur-Fen Gau, Dai-Hua Lu, Houng-Chi Liou, Huang-Ju Tu, Hsiao-Mei Liao, and Wen-Mei Fu
- Subjects
0301 basic medicine ,Male ,medicine.medical_specialty ,Serotonin ,Autism Spectrum Disorder ,Morris water navigation task ,lcsh:RC346-429 ,03 medical and health sciences ,Norepinephrine ,Mice ,0302 clinical medicine ,Developmental Neuroscience ,Dopamine ,Internal medicine ,medicine ,Animals ,Learning ,Social Behavior ,Molecular Biology ,Monoamine Oxidase ,lcsh:Neurology. Diseases of the nervous system ,biology ,business.industry ,Research ,Institutional Animal Care and Use Committee ,Brain ,medicine.disease ,Mice, Inbred C57BL ,Psychiatry and Mental health ,030104 developmental biology ,Endocrinology ,Autism spectrum disorder ,Social deficits ,Knockout mouse ,biology.protein ,Monoamine oxidase A ,ARHGEF10 ,business ,030217 neurology & neurosurgery ,Rho Guanine Nucleotide Exchange Factors ,Developmental Biology ,Social behavior ,medicine.drug - Abstract
Background Impaired social interaction is one of the essential features of autism spectrum disorder (ASD). Our previous copy number variation (CNV) study discovered a novel deleted region associated with ASD. One of the genes included in the deleted region is ARHGEF10. A missense mutation of ARHGEF10 has been reported to be one of the contributing factors in several diseases of the central nervous system. However, the relationship between the loss of ARHGEF10 and the clinical symptoms of ASD is unclear. Methods We generated Arhgef10 knockout mice as a model of ASD and characterized the social behavior and the biochemical changes in the brains of the knockout mice. Results Compared with their wild-type littermates, the Arhgef10-depleted mice showed social interaction impairment, hyperactivity, and decreased depression-like and anxiety-like behavior. Behavioral measures of learning in the Morris water maze were not affected by Arhgef10 deficiency. Moreover, neurotransmitters including serotonin, norepinephrine, and dopamine were significantly increased in different brain regions of the Arhgef10 knockout mice. In addition, monoamine oxidase A (MAO-A) decreased in several brain regions. Conclusions These results suggest that ARHGEF10 is a candidate risk gene for ASD and that the Arhgef10 knockout model could be a tool for studying the mechanisms of neurotransmission in ASD. Trial registration Animal studies were approved by the Institutional Animal Care and Use Committee of National Taiwan University (IACUC 20150023). Registered 1 August 2015. Electronic supplementary material The online version of this article (10.1186/s13229-018-0197-5) contains supplementary material, which is available to authorized users.
- Published
- 2018
20. Role of Spinal CXCL1 (GROα) in Opioid Tolerance
- Author
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Kai-Hsiang Kang, Houng Chi Liou, Wen-Mei Fu, Woei Jer Chuang, Tzu-Hung Lin, Chih-Peng Lin, Wei-Zen Sun, and Ming-Yueh Wu
- Subjects
business.industry ,medicine.medical_treatment ,Analgesic ,Intraperitoneal injection ,Antagonist ,respiratory system ,Pharmacology ,CXCL1 ,Anesthesiology and Pain Medicine ,Cerebrospinal fluid ,Opioid ,Drug tolerance ,Immunology ,Morphine ,medicine ,business ,medicine.drug - Abstract
Background: The pivotal role of glial activation and up-regulated inflammatory mediators in the opioid tolerance has been confirmed in rodents but not yet in humans. Here, the authors investigated the intraspinal cytokine and chemokine profiles of opioid-tolerant cancer patients; and to determine if up-regulated chemokines could modify opioid tolerance in rats. Methods: Cerebrospinal fluid samples from opioid-tolerant cancer patients and opioid-naive subjects were compared. The cerebrospinal fluid levels of tumor necrosis factor-alpha, CXCL1, CXCL10, CCL2, and CX3CL1 were assayed. The rat tail flick test was utilized to assess the effects of intrathecal CXCL1 on morphine-induced acute antinociception and analgesic tolerance. Results: CXCL1 level in cerebrospinal fluid was significantly up-regulated in the opioid-tolerant group (n = 30, 18.8 pg/ml vs. 13.2 pg/ml, P = 0.02) and was positively correlated (r2 = 0.49, P < 0.01) with opioid dosage. In rat experiment, after induction of tolerance by morphine infusion, the spinal cord CXCL1 messenger RNA was up-regulated to 32.5 ± 11.9-fold. Although CXCL1 infusion alone did not affect baseline tail-flick latency, the analgesic efficacy of a single intraperitoneal injection of morphine dropped significantly on day 1 to day 3 after intrathecal infusion of CXCL1. After establishing tolerance by intrathecal continuous infusion of morphine, its development was accelerated by coadministration of CXCL1 and attenuated by coadministration of CXCL1-neutralizing antibody or CXCR2 antagonist. Conclusions: CXCL1 is up-regulated in both opioid-tolerant patients and rodents. The onset and extent of opioid tolerance was affected by antagonizing intrathecal CXCL1/CXCR2 signaling. Therefore, the CXCL1/CXCR2 signal pathway may be a novel target for the treatment of opioid tolerance.
- Published
- 2015
21. Growth hormone is increased in the lungs and enhances experimental lung metastasis of melanoma in DJ-1 KO mice
- Author
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Houng-Chi Liou, Ming-Jen Lee, Chia-Hung Chien, Horng-Huei Liou, and Wen-Mei Fu
- Subjects
0301 basic medicine ,Male ,Cancer Research ,medicine.medical_specialty ,Lung Neoplasms ,Cell Survival ,Protein Deglycase DJ-1 ,Melanoma, Experimental ,Growth hormone receptor ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Cell Movement ,Internal medicine ,Cell Line, Tumor ,Genetics ,medicine ,Animals ,Autocrine signalling ,Melanoma ,Lung ,Oncogenesis ,Tumor Stem Cell Assay ,Cell Proliferation ,Mice, Knockout ,business.industry ,Cell growth ,Solitary Pulmonary Nodule ,Transfection ,medicine.disease ,Matrix Metalloproteinases ,Tumor Burden ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Endocrinology ,Lung metastasis ,Oncology ,Cell culture ,Tumor progression ,030220 oncology & carcinogenesis ,Growth Hormone ,business ,Research Article ,Knockout mice - Abstract
Background Growth hormone (GH) mainly serves an endocrine function to regulate somatic growth, but also serves an autocrine function in lung growth and pulmonary function. Several recent studies have demonstrated the role of autocrine GH in tumor progression in some organs. However, it is not clear whether excessive secretion of GH in the lungs is related to pulmonary nodule formation. Methods Firstly, the lung tissues dissected from mice were used for Western blotting and PCR measurement. Secondly, the cultured cells were used for examining effects of GH on B16F10 murine melanoma cells. Thirdly, male C57BL/6 mice were intravenously injected with B16F10 cells and then subcutaneously injected with recombinant GH twice per week for three weeks. Finally, stably transfected pool of B16F10 cells with knockdown of growth hormone receptor (GHR) was used to be injected into mice. Results We found that expression of GH was elevated in the lungs of DJ-1 knockout (KO) mice. We also examined the effects of GH on the growth of cultured melanoma cells. The results showed that GH increased proliferation, colony formation, and invasive capacity of B16F10 cells. In addition, GH also increased the expression of matrix metalloproteinases (MMPs) in B16F10 cells. Administration of GH in vivo enhanced lung nodule formation in C57/B6 mice. Increased lung nodule formation in DJ-1 KO mice following intravenous injection of melanoma cells was inhibited by GHR knockdown in B16F10 cells. Conclusions These results indicate that up-regulation of GH in the lungs of DJ-1 KO mice may enhance the malignancy of B16F10 cells and nodule formation in pulmonary metastasis of melanoma. Electronic supplementary material The online version of this article (doi:10.1186/s12885-016-2898-5) contains supplementary material, which is available to authorized users.
- Published
- 2016
22. Pulsed-wave low-dose ultrasound hyperthermia selectively enhances nanodrug delivery and improves antitumor efficacy for brain metastasis of breast cancer
- Author
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Chi-Feng Chiang, Wen-Mei Fu, Yu-Hone Hsu, Sheng-Kai Wu, Win-Li Lin, and Houng-Chi Liou
- Subjects
0301 basic medicine ,Hyperthermia ,Pathology ,medicine.medical_specialty ,Acoustics and Ultrasonics ,Brain tumor ,Antineoplastic Agents ,Apoptosis ,Breast Neoplasms ,02 engineering and technology ,Polyethylene Glycols ,Inorganic Chemistry ,03 medical and health sciences ,Mice ,Breast cancer ,Drug Delivery Systems ,Cell Line, Tumor ,medicine ,Chemical Engineering (miscellaneous) ,Environmental Chemistry ,Distribution (pharmacology) ,Animals ,Radiology, Nuclear Medicine and imaging ,Doxorubicin ,Luciferase ,Cell Proliferation ,business.industry ,Brain Neoplasms ,Organic Chemistry ,Hyperthermia, Induced ,021001 nanoscience & nanotechnology ,medicine.disease ,Erratum and Corrigendum ,Nanostructures ,030104 developmental biology ,Ultrasonic Waves ,Cancer research ,lipids (amino acids, peptides, and proteins) ,0210 nano-technology ,business ,Brain metastasis ,medicine.drug - Abstract
The clinical application of chemotherapeutics for brain tumors remains a challenge due to limitation of blood-brain barrier/blood-tumor barrier (BBB/BTB). In this study, we investigated the effects of low-dose focused ultrasound hyperthermia (UH) on the delivery and therapeutic efficacy of pegylated liposomal doxorubicin (PLD) for brain metastasis of breast cancer. Murine breast cancer cells (4T1-luc2) expressing firefly luciferase were implanted into mouse striatum as a brain tumor model. The mice were intravenously injected with PLD with/without transcranial pulsed-wave/continuous-wave UH (pUH/cUH) treatment on day-6 after tumor implantation. pUH (frequency: 500kHz, PRF: 1000Hz, duty cycle: 50%) was conducted under equal acoustic power (2.2-Watt) and sonication duration (10-min) as cUH. The amounts of doxorubicin accumulated in the normal brain and tumor tissues were measured with fluorometry. The tumor growth responses for the control, pUH, PLD, PLD+cUH, and PLD+pUH groups were evaluated with IVIS. The PLD distribution and cell apoptosis were assessed with immunofluorescence staining. The results showed that pUH significantly enhanced the PLD delivery into brain tumors and the tumor growth was further inhibited by PLD+pUH without damaging the sonicated normal brain tissues. This indicates that low-dose transcranial pUH is a promising method to selectively enhance nanodrug delivery and improve the brain tumor treatment.
- Published
- 2016
23. Key opioid prescription concerns in cancer patients: A nationwide study
- Author
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Yu-Yun Shao, Ying-Hui Lee, Chih-Hung Hsu, Wen-Mei Fu, Chih-Peng Lin, Ho-Min Chen, and Mei-Shu Lai
- Subjects
Adult ,Male ,medicine.medical_specialty ,Propoxyphene ,Taiwan ,Drug Prescriptions ,Fentanyl ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,Aged ,business.industry ,Codeine ,General Medicine ,Cancer Pain ,Health Care Costs ,Middle Aged ,Nalbuphine ,Analgesics, Opioid ,Anesthesiology and Pain Medicine ,Opioid ,030220 oncology & carcinogenesis ,Anesthesia ,Female ,Tramadol ,Cancer pain ,business ,medicine.drug ,Buprenorphine - Abstract
Background Opioids are crucial in cancer pain management. We examined the nationwide prescription patterns of opioids in Taiwan cancer patients to find the potential concerns. Methods We reviewed the claims database of the National Health Insurance of Taiwan for patients diagnosed with cancer from 2003 to 2011. The use and cost of analgesics were analyzed. Opioids were classified into recommended strong opioids (morphine and transdermal fentanyl), recommended weak opioids (tramadol, buprenorphine, and codeine), and unrecommended opioids (propoxyphene, nalbuphine, and meperidine). Results We enrolled 1,424,048 patients with cancer, and ∼50% of them took analgesics. Among analgesic users, patients who used opioids increased from 48.2% in 2003 to 52.0% in 2010. Approximately 92% of the opioid use came from recommended opioids, either strong (51%) or weak opioids (41%). The ratio of the use of short-acting strong opioids to that of long-acting opioids increased from 0.41 in 2003 to 0.63 in 2011. Transdermal fentanyl accounted for > 50% of the use of strong opioids. Among weak opioids, the use of tramadol gradually increased to 71% in 2011. On average, opioids contributed to 0.79‰ of all medical expenditures and 2.94‰ of all medication costs. Conclusion The use of short-acting strong opioids increased during the study period. Instead of oral opioids, transdermal fentanyl was the most commonly used opioid among Taiwan cancer patients. The use of weak opioids, particularly tramadol, was high. These concerns should be the focus of pain management education.
- Published
- 2016
24. Integrin-linked kinase as a novel molecular switch of the IL-6-NF-κB signaling loop in breast cancer
- Author
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Jianying Zhang, Ming Chen Yang, Che-Ming Teng, Samuel K. Kulp, Max S. Wicha, Wen Chung Chen, Ching-Shih Chen, Huang Ju Tu, Santosh B. Salunke, Han Li Huang, En-Chi Hsu, Yu Chou Tseng, Duxin Sun, Nicholas J. Sullivan, Charles L. Shapiro, Min Wu Chao, and Wen-Mei Fu
- Subjects
0301 basic medicine ,Cancer Research ,Gene knockdown ,biology ,Chemistry ,Effector ,Kinase ,Interleukin-6 ,NF-kappa B ,Breast Neoplasms ,Original Manuscript ,General Medicine ,Protein Serine-Threonine Kinases ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,Downregulation and upregulation ,Cancer stem cell ,embryonic structures ,biology.protein ,E2F1 ,Humans ,Integrin-linked kinase ,Signal transduction ,Signal Transduction - Abstract
Substantial evidence has clearly demonstrated the role of the IL-6-NF-κB signaling loop in promoting aggressive phenotypes in breast cancer. However, the exact mechanism by which this inflammatory loop is regulated remains to be defined. Here, we report that integrin-linked kinase (ILK) acts as a molecular switch for this feedback loop. Specifically, we show that IL-6 induces ILK expression via E2F1 upregulation, which, in turn, activates NF-κB signaling to facilitate IL-6 production. shRNA-mediated knockdown or pharmacological inhibition of ILK disrupted this IL-6-NF-κB signaling loop, and blocked IL-6-induced cancer stem cells in vitro and estrogen-independent tumor growth in vivo Together, these findings establish ILK as an intermediary effector of the IL-6-NF-κB feedback loop and a promising therapeutic target for breast cancer.
- Published
- 2015
25. Involvement of Arhgef10 in social behaviour
- Author
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Dai-Hua Lu, Houng-Chi Liou, Hsiao-Mei Liao, Wen-Mei Fu, Chia-Hsiang Chen, Wan-Wan Lin, and Susan Shur-Fen Gau
- Subjects
Applied Mathematics ,General Mathematics ,Social behaviour ,Psychology ,Social psychology - Published
- 2018
26. Autophagy protects neuron from Aβ-induced cytotoxicity
- Author
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Houng-Chi Liou, Shih-Ya Hung, Wei-Pang Huang, and Wen-Mei Fu
- Subjects
Nicotine ,Programmed cell death ,alpha7 Nicotinic Acetylcholine Receptor ,Green Fluorescent Proteins ,Ubiquitin-Activating Enzymes ,Vacuole ,Receptors, Nicotinic ,Biology ,Autophagy-Related Protein 7 ,Hippocampus ,Neuroprotection ,Wortmannin ,chemistry.chemical_compound ,Cell Line, Tumor ,Phagosomes ,mental disorders ,Autophagy ,medicine ,Animals ,Humans ,Rats, Wistar ,Molecular Biology ,Cells, Cultured ,Neurons ,Amyloid beta-Peptides ,Neurotoxicity ,Colocalization ,Cell Biology ,medicine.disease ,Rats ,nervous system diseases ,Cell biology ,Androstadienes ,chemistry ,Cytoprotection ,Gene Knockdown Techniques ,Macrolides ,Microtubule-Associated Proteins - Abstract
Autophagy is a degradation pathway for the turnover of dysfunctional organelles or aggregated proteins in cells. Extracellular accumulation of beta-amyloid peptide has been reported to be a major cause of Alzheimer disease (AD) and large numbers of autophagic vacuoles accumulate in the brain of AD patient. However, how autophagic process is involved in Abeta-induced neurotoxicity and how Abeta peptide is transported into the neuron and metabolized is still unknown. In order to study the role of autophagic process in Abeta-induced neurotoxicity, EGFP-LC3 was overexpressed in SH-SY5Y cells (SH-SY5Y/pEGFP-LC3). It was found that treatment with Abeta(25-35), Abeta(1-42) or serum-starvation induced strong autophagy response in SH-SY5Y/pEGFP-LC3. Confocal double-staining image showed that exogenous application of Abeta(1-42) in medium caused the colocalization of Abeta(1-42) with LC3 in neuronal cells. Concomitant treatment of Abeta with a selective alpha7nAChR antagonist, alpha-bungarotoxin (alpha-BTX), enhanced Abeta-induced neurotoxicity in SH-SY5Y cells. On the other hand, nicotine (nAChR agonist) enhanced the autophagic process and also inhibited cell death following Abeta application. In addition, nicotine but not alpha-BTX increased primary hippocampal neuronal survival following Abeta treatment. Furthermore, using Atg7 siRNA to inhibit autophagosome formation in an early step or alpha7nAChR siRNA to knock down alpha7nAChR significantly enhanced Abeta-induced neurotoxicity. Confocal double-staining imaging shows that nicotine treatment in the presence of Abeta enhanced the colocalization of alpha7nAChR with autophagosomes. These results suggest that alpha7nAChR may act as a carrier to bind with eAbeta and internalize into cytoplasm and further inhibit Abeta-induced neurotoxicity via autophagic degradation pathway. Our results suggest that autophagy process plays a neuroprotective role against Abeta-induced neurotoxicity. Defect in autophagic regulation or Abeta-alpha7nAChR transport system may impair the clearance of Abeta and enhance neuronal death.
- Published
- 2009
27. Leptin induces migration and invasion of glioma cells through MMP-13 production
- Author
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Wei-Lan Yeh, Ming-Jen Lee, Wen-Mei Fu, and Dah-Yuu Lu
- Subjects
Leptin ,medicine.medical_specialty ,Cell type ,Protein Serine-Threonine Kinases ,Biology ,Transfection ,p38 Mitogen-Activated Protein Kinases ,Antibodies ,Cellular and Molecular Neuroscience ,Cell Movement ,Cell Line, Tumor ,Internal medicine ,Glioma ,Matrix Metalloproteinase 13 ,medicine ,Animals ,Humans ,Neoplasm Invasiveness ,RNA, Messenger ,Enzyme Inhibitors ,Regulation of gene expression ,Leptin receptor ,Dose-Response Relationship, Drug ,Brain Neoplasms ,digestive, oral, and skin physiology ,Cell migration ,medicine.disease ,Rats ,Gene Expression Regulation, Neoplastic ,Endocrinology ,Neurology ,Cell culture ,Astrocytes ,Cancer research ,Receptors, Leptin ,hormones, hormone substitutes, and hormone antagonists ,Signal Transduction - Abstract
Leptin, the product of the obese gene, plays an important role in the regulation of body weight by coordinating metabolism, feeding behavior, energy balance, and neuroendocrine responses. However, regulation of leptin gene expression in the central nervous system is different from that in the adipocytes. In addition, leptin has been found in many tumor cell lines and has been shown to have mitogenic and angiogenic activity in a number of cell types. Glioma is the most common primary adult brain tumor with poor prognosis because of the spreading of tumor cell to the other regions of brain easily. Here we found that malignant C6 glioma cells expressed more leptin and leptin receptors than nonmalignant astrocytes. Furthermore, it was found that exogenous application of leptin enhanced the migration and invasion of C6 glioma cells. In addition, we found that the expression of matrix metalloproteinase-13 (MMP-13) but not of MMP-2 and MMP-9 was increased in response to leptin stimulation. The leptin-induced increase of cell migration and invasion was antagonized by MMP-13 neutralizing antibody or silencing MMP-13. The up-regulation of MMP-13 induced by leptin was mainly through p38 MAP kinase and NF-kappaB pathway. In addition, migration-prone sublines demonstrate that cells with increasing migration ability had more expression of MMP-13 and leptin. Taken together, these results indicate that leptin enhanced migration and invasion of C6 glioma cells through the increase of MMP-13 production.
- Published
- 2009
28. Enhancement of active shuttle avoidance response by the NO-cGMP-PKG activator YC-1
- Author
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Wen-Mei Fu, Keng-Chen Liang, and Wei-Lin Chien
- Subjects
Male ,MAPK/ERK pathway ,Indazoles ,MAP Kinase Signaling System ,Long-Term Potentiation ,Avoidance response ,Nitric Oxide ,CREB ,Amygdala ,Avoidance Learning ,Cyclic GMP-Dependent Protein Kinases ,medicine ,Animals ,RNA, Messenger ,Fear conditioning ,Phosphorylation ,Rats, Wistar ,Extracellular Signal-Regulated MAP Kinases ,Cyclic GMP ,Pharmacology ,Brain-derived neurotrophic factor ,biology ,Brain-Derived Neurotrophic Factor ,MEK inhibitor ,Long-term potentiation ,Rats ,medicine.anatomical_structure ,biology.protein ,Psychology ,Proto-Oncogene Proteins c-akt ,Proto-Oncogene Proteins c-fos ,Neuroscience - Abstract
Although much has been learned about the role of the amygdala in Pavlovian fear conditioning, relatively little is known about the signaling pathway involved in the acquisition of an active avoidance reaction. The aim of this study is to investigate the potentiating effects of the NO-guanylate cyclase activator YC-1 on learning and memory of shuttle avoidance test in rats. YC-1 enhanced the induction of long-term potentiation (LTP) in amygdala through NO-cGMP-PKG-ERK pathway and the increase of BDNF expression. The Western blot and PCR methods were used to examine the signaling pathways involved in fear memory. It was found that YC-1 increased the avoidance responses during learning period and the memory retention lasted longer than one week. The enhancement of learning behavior by YC-1 was antagonized by intracerebroventricular injection of NOS inhibitor l-NAME, PKG inhibitor Rp-8-Br-PET-cGMPS and MEK inhibitor PD98059, indicating that NO-cGMP-PKG and ERK pathways are involved in the learning potentiating action of YC-1. In addition, YC-1 increased the activation of ERK and Akt 30 min after Day-1 training in amygdala. YC-1 also potentiated the expression of BDNF and CREB in response to fear memory test. Taken together, these findings suggest that NO-cGMP-PKG-ERK signaling pathway is involved in the action of YC-1 in enhancing the fear memory.
- Published
- 2008
29. Osteoblast-Derived TGF-β1 Stimulates IL-8 Release Through AP-1 and NF-κB in Human Cancer Cells
- Author
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Jaung Geng Lin, Rong-Sen Yang, Chih-Hsin Tang, Long Bin Jeng, Wen Chi Chen, Fuu Jen Tsai, Ming Chei Maa, Wen-Mei Fu, and Yi-Chin Fong
- Subjects
MAPK/ERK pathway ,Small interfering RNA ,Endocrinology, Diabetes and Metabolism ,Biology ,Bone resorption ,Transforming Growth Factor beta1 ,Cell Line, Tumor ,Neoplasms ,medicine ,Humans ,Orthopedics and Sports Medicine ,Promoter Regions, Genetic ,Protein Kinase Inhibitors ,TGF beta 1 ,Osteoblasts ,Activator (genetics) ,Kinase ,Interleukin-8 ,NF-kappa B ,Osteoblast ,Transfection ,Culture Media ,Enzyme Activation ,Transcription Factor AP-1 ,medicine.anatomical_structure ,Cancer research ,biology.protein ,Mitogen-Activated Protein Kinases ,Protein Binding - Abstract
Introduction: The bone marrow microenvironment is further enriched by growth factors released during osteoclastic bone resorption. It has been reported that the chemokine interleukin (IL)-8 is a potent and direct activator of osteoclastic differentiation and bone resorption. However, the effect of bone-derived growth factors on the IL-8 production in human cancer cells and the promotion of osteoclastogenesis are largely unknown. The aim of this study was to investigate whether osteoblast-derived TGF-β1 is associated with osteolytic bone diseases. Materials and Methods: IL-8 mRNA levels were measured using RT-PCR analysis. MAPK phosphorylation was examined using the Western blot method. siRNA was used to inhibit the expression of TGF-β1, BMP-2, and IGF-1. DNA affinity protein-binding assay and chromatin immunoprecipitation assays were used to study in vitro and in vivo binding of c-fos, c-jun, p65, and p50 to the IL-8 promoter. A transient transfection protocol was used to examine IL-8, NF-κB, and activator protein (AP)-1 activity. Results: Osteoblast conditioned medium (OBCM) induced activation of IL-8, AP-1, and NF-κB promoter in human cancer cells. Osteoblasts were transfected with TGF-β1, BMP-2, or IGF-1 small interfering RNA, and the medium was collected after 48 h. TGF-β1 but not BMP-2 or IGF-1 siRNA inhibited OBCM-induced IL-8 release in human cancer cells. In addition, TGF-β1 also directly induced IL-8 release in human cancer cells. Activation of AP-1 and NF-κB DNA-protein binding and MAPKs after TGF-β1 treatment was shown, and TGF-β1–induced IL-8 promoter activity was inhibited by the specific inhibitors of MAPK cascades. Conclusions: In this study, we provide evidence to show that the osteoblasts release growth factors, including TGF-β1, BMP-2, and IGF-1. TGF-β1 is the major contributor to the activation of extracellular signal-related kinase (ERK), p38, and c-Jun N-terminal kinase (JNK), leading to the activation of AP-1 and NF-κB on the IL-8 promoter and initiation of IL-8 mRNA and protein release, thereby promoting osteoclastogenesis.
- Published
- 2008
30. Ultrasound Induces Hypoxia-inducible Factor-1 Activation and Inducible Nitric-oxide Synthase Expression through the Integrin/Integrin-linked Kinase/Akt/Mammalian Target of Rapamycin Pathway in Osteoblasts
- Author
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Tzu-Wei Tan, Wen-Mei Fu, Chih-Hsin Tang, Rong-Sen Yang, and Dah-Yuu Lu
- Subjects
Nitric Oxide Synthase Type II ,Stimulation ,Protein Serine-Threonine Kinases ,Nitric Oxide ,Response Elements ,Biochemistry ,Antibodies ,Gene Expression Regulation, Enzymologic ,Cell Line ,Fractures, Bone ,Mice ,Sonication ,Animals ,Integrin-linked kinase ,Kinase activity ,Protein Kinase Inhibitors ,Molecular Biology ,Protein kinase B ,PI3K/AKT/mTOR pathway ,Fracture Healing ,Osteoblasts ,biology ,Akt/PKB signaling pathway ,Chemistry ,TOR Serine-Threonine Kinases ,Cell Biology ,Hypoxia-Inducible Factor 1, alpha Subunit ,Integrin alphaVbeta3 ,Molecular biology ,Up-Regulation ,Cell biology ,Nitric oxide synthase ,Disease Models, Animal ,Focal Adhesion Kinase 1 ,biology.protein ,Phosphorylation ,Protein Kinases ,Proto-Oncogene Proteins c-akt ,Integrin alpha5beta1 ,Protein Binding ,Signal Transduction - Abstract
It has been shown that ultrasound (US) stimulation accelerates fracture healing in the animal models and clinical studies. Nitric oxide (NO) is a crucial early mediator in mechanically induced bone formation. Here we found that US stimulation increased NO formation and the protein level of inducible nitric-oxide synthase (iNOS). US-mediated iNOS expression was attenuated by anti-integrin alpha5beta1 or beta1 antibodies but not anti-integrin alphavbeta3 or beta3 antibodies or focal adhesion kinase mutant. Integrin-linked kinase (ILK) inhibitor (KP-392), Akt inhibitor (1L-6-hydroxymethyl-chiro-inositol-2-[(R)-2-O-methyl-3-O-octadecylcarbonate]) or mammalian target of rapamycin (mTOR) inhibitor (rapamycin) also inhibited the potentiating action of US. US stimulation increased the kinase activity of ILK and phosphorylation of Akt and mTOR. Furthermore, US stimulation also increased the stability and activity of HIF-1 protein. The binding of HIF-1alpha to the HRE elements on the iNOS promoter was enhanced by US stimulation. Moreover, the use of pharmacological inhibitors or genetic inhibition revealed that both ILK/Akt and mTOR signaling pathway were potentially required for US-induced HIF-1alpha activation and subsequent iNOS up-regulation. Taken together, our results provide evidence that US stimulation up-regulates iNOS expression in osteoblasts by an HIF-1alpha-dependent mechanism involving the activation of ILK/Akt and mTOR pathways via integrin receptor.
- Published
- 2007
31. Mice Deficient in Collapsin Response Mediator Protein-1 Exhibit Impaired Long-Term Potentiation and Impaired Spatial Learning and Memory
- Author
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Pei-Hsing Huang, Hsiang-Po Huang, Wen-Mei Fu, Pan-Chyr Yang, I-Shing Yu, Shu-Rung Lin, Wei-Lin Chien, Yi-Ling Lin, Shu-Wha Lin, Kang-Yi Su, Yi-Ping Hsueh, and Jin-Yuan Shih
- Subjects
Synapsin I ,Neurite ,Long-Term Potentiation ,Morris water navigation task ,Hippocampus ,Nerve Tissue Proteins ,Hippocampal formation ,Mice ,GAP-43 Protein ,Memory ,Postsynaptic potential ,Animals ,Maze Learning ,Swimming ,Mice, Knockout ,CRMP1 ,Chemistry ,General Neuroscience ,Intracellular Signaling Peptides and Proteins ,Brain ,Membrane Proteins ,Long-term potentiation ,Articles ,Phosphoproteins ,Cell biology ,Animals, Newborn ,nervous system ,Disks Large Homolog 4 Protein ,Guanylate Kinases ,Neuroscience - Abstract
Collapsing response mediator protein-1 (CRMP-1) was initially identified in brain and has been implicated in plexin-dependent neuronal function. The high amino acid sequence identity among the five CRMPs has hindered determination of the functions of each individual CRMP. We generated viable and fertileCRMP-1knock-out (CRMP-1−/−) mice with no evidence of gross abnormality in the major organs.CRMP-1−/−mice exhibited intense microtubule-associated protein 2 (MAP2) staining in the proximal portion of the dendrites, but reduced and disorganized MAP2 staining in the distal dendrites of hippocampal CA1 pyramidal cells. Immunoreactivity to GAP-43 (growth-associated protein-43) and PSD95 (postsynaptic density-95) (a postsynaptic membrane adherent cytoskeletal protein) was also decreased in the CA1 region of the knock-out mice. These changes were consistent with the mutant mice showing a reduction in long-term potentiation (LTP) in the CA1 region and impaired performance in hippocampal-dependent spatial learning and memory tests.CRMP-1−/−mice showed a normal synapsin I labeling pattern in CA1 and normal paired-pulse facilitation. These findings provide the first evidence suggesting that CRMP-1 may be involved in proper neurite outgrowth in the adult hippocampus and that loss of CRMP-1 may affect LTP maintenance and spatial learning and memory.
- Published
- 2007
32. Attention deficits revealed by passive auditory change detection for pure tones and lexical tones in ADHD children
- Author
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Chia-Ying Lee, Pei Wen Yeh, Jao Shwann Liang, Chun Hsien Hsu, Wen-Mei Fu, Wang-Tso Lee, and Ming Tao Yang
- Subjects
late discriminative negativity ,Mismatch negativity ,Mandarin Chinese ,behavioral disciplines and activities ,lcsh:RC321-571 ,Behavioral Neuroscience ,P3a ,event-related potential ,Event-related potential ,mental disorders ,medicine ,Attention deficit hyperactivity disorder ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Oddball paradigm ,Biological Psychiatry ,Original Research ,Attentional control ,Cognition ,attention deficit-hyperactivity disorder ,medicine.disease ,language.human_language ,Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Neurology ,language ,passive auditory discrimination ,mismatch negativity ,Psychology ,Cognitive psychology ,Neuroscience - Abstract
Inattention (IA) has been a major problem in children with attention deficit/hyperactivity disorder (ADHD), accounting for their behavioral and cognitive dysfunctions. However, there are at least three processing steps underlying attentional control for auditory change detection, namely pre-attentive change detection, involuntary attention orienting, and attention reorienting for further evaluation. This study aimed to examine whether children with ADHD would show deficits in any of these subcomponents by using mismatch negativity (MMN), P3a, and late discriminative negativity (LDN) as event-related potential (ERP) markers, under the passive auditory oddball paradigm. Two types of stimuli—pure tones and Mandarin lexical tones—were used to examine if the deficits were general across linguistic and non-linguistic domains. Participants included 15 native Mandarin-speaking children with ADHD and 16 age-matched controls (across groups, age ranged between 6 and 15 years). Two passive auditory oddball paradigms (lexical tones and pure tones) were applied. The pure tone oddball paradigm included a standard stimulus (1000 Hz, 80%) and two deviant stimuli (1015 and 1090 Hz, 10% each). The Mandarin lexical tone oddball paradigm’s standard stimulus was /yi3/ (80%) and two deviant stimuli were /yi1/ and /yi2/ (10% each). The results showed no MMN difference, but did show attenuated P3a and enhanced LDN to the large deviants for both pure and lexical tone changes in the ADHD group. Correlation analysis showed that children with higher ADHD tendency, as indexed by parents’ and teachers’ ratings on ADHD symptoms, showed less positive P3a amplitudes when responding to large lexical tone deviants. Thus, children with ADHD showed impaired auditory change detection for both pure tones and lexical tones in both involuntary attention switching, and attention reorienting for further evaluation. These ERP markers may therefore be used for the evaluation of anti-ADHD drugs that aim to alleviate these dysfunctions.
- Published
- 2015
33. Local immunosuppressive microenvironment enhances migration of melanoma cells to lungs in DJ-1 knockout mice
- Author
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Ming-Jen Lee, Wen-Mei Fu, Chia-Hung Chien, Horng-Huei Liou, and Houng-Chi Liou
- Subjects
Lung Neoplasms ,Interleukin-1beta ,Protein Deglycase DJ-1 ,lcsh:Medicine ,Mice ,Cell Movement ,Cell Line, Tumor ,medicine ,Macrophage ,Animals ,Myeloid Cells ,Neoplasm Invasiveness ,Lymphocytes ,lcsh:Science ,Melanoma ,Oncogene Proteins ,Gene knockdown ,Multidisciplinary ,biology ,lcsh:R ,Cancer ,Peroxiredoxins ,medicine.disease ,Mice, Inbred C57BL ,Cellular Microenvironment ,Cell culture ,Knockout mouse ,Immunology ,Cancer cell ,Cancer research ,biology.protein ,lcsh:Q ,Antibody ,Research Article - Abstract
DJ-1 is an oncoprotein that promotes survival of cancer cells through anti-apoptosis. However, DJ-1 also plays a role in regulating IL-1β expression, and whether inflammatory microenvironment built by dysregulated DJ-1 affects cancer progression is still unclear. This study thus aimed to compare the metastatic abilities of melanoma cells in wild-type (WT) and DJ-1 knockout (KO) mice, and to check whether inflammatory microenvironment built in DJ-1 KO mice plays a role in migration of cancer cells to lungs. First, B16F10 melanoma cells (at 6 × 10(4)) were injected into the femoral vein of mice, and formation of lung nodules, levels of lung IL-1β and serum cytokines, and accumulation of myeloid-derived suppressor cells (MDSCs) were compared between WT and DJ-1 KO mice. Second, the cancer-bearing mice were treated with an interleukin-1 beta (IL-1β) neutralizing antibody to see whether IL-1β is involved in the cancer migration. Finally, cultured RAW 264.7 macrophage and B16F10 melanoma cells were respectively treated with DJ-1 shRNA and recombinant IL-1β to explore underlying molecular mechanisms. Our results showed that IL-1β enhanced survival and colony formation of cultured melanoma cells, and that IL-1β levels were elevated both in DJ-1 KO mice and in cultured macrophage cells with DJ-1 knockdown. The elevated IL-1β correlated with higher accumulation of immunosuppressive MDSCs and formation of melanoma module in the lung of DJ-1 KO mice, and both can be decreased by treating mice with IL-1β neutralizing antibodies. Taken together, these results indicate that immunosuppressive tissue microenvironment built in DJ-1 KO mice can enhance lung migration of cancer, and IL-1β plays an important role in promoting the cancer migration.
- Published
- 2015
34. NRIP is a novel Z-disc protein to activate calmodulin signaling for skeletal muscle contraction and regeneration
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Wen-Pin Chen, Szu-Wei Chang, Yuan-Chun Huang, Yeou-Ping Tsao, Wen-Mei Fu, Wan-Lun Yan, Hsin-hsiung Chen, I-Shing Yu, Yu-Ting Yan, Ming-Jai Su, Show-Li Chen, and Tzung-Chieh Tsai
- Subjects
medicine.medical_specialty ,Calmodulin ,Myogenesis ,Skeletal muscle ,Cell Biology ,Biology ,Cell biology ,Endocrinology ,medicine.anatomical_structure ,Internal medicine ,Ca2+/calmodulin-dependent protein kinase ,Myosin ,medicine ,biology.protein ,Desmin ,medicine.symptom ,Myogenin ,Muscle contraction - Abstract
Nuclear receptor interaction protein (NRIP, also known as DCAF6 and IQWD1) is a Ca(2+)-dependent calmodulin-binding protein. In this study, we newly identify NRIP as a Z-disc protein in skeletal muscle. NRIP-knockout mice were generated and found to have reduced muscle strength, susceptibility to fatigue and impaired adaptive exercise performance. The mechanisms of NRIP-regulated muscle contraction depend on NRIP being downstream of Ca(2+) signaling, where it stimulates activation of both 'calcineurin-nuclear factor of activated T-cells, cytoplasmic 1' (CaN-NFATc1; also known as NFATC1) and calmodulin-dependent protein kinase II (CaMKII) through interaction with calmodulin (CaM), resulting in the induction of mitochondrial activity and the expression of genes encoding the slow class of myosin, and in the regulation of Ca(2+) homeostasis through the internal Ca(2+) stores of the sarcoplasmic reticulum. Moreover, NRIP-knockout mice have a delayed regenerative capacity. The amount of NRIP can be enhanced after muscle injury and is responsible for muscle regeneration, which is associated with the increased expression of myogenin, desmin and embryonic myosin heavy chain during myogenesis, as well as for myotube formation. In conclusion, NRIP is a novel Z-disc protein that is important for skeletal muscle strength and regenerative capacity.
- Published
- 2015
35. Hypoxic Preconditioning Suppresses Glial Activation and Neuroinflammation in Neonatal Brain Insults
- Author
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Po-Nien Tsao, Wu-Shiun Hsieh, Chien-Yi Chen, Wei-Zen Sun, Hung-Chieh Chou, Wen-Mei Fu, and Kai-Hsiang Kang
- Subjects
Male ,Article Subject ,Immunology ,Pharmacology ,Neuroprotection ,Proinflammatory cytokine ,Rats, Sprague-Dawley ,Downregulation and upregulation ,lcsh:Pathology ,Medicine ,Animals ,Hypoxia ,Ischemic Preconditioning ,Neuroinflammation ,Microglia ,business.industry ,Brain ,Cell Biology ,Hypoxia (medical) ,In vitro ,Rats ,Disease Models, Animal ,medicine.anatomical_structure ,Animals, Newborn ,Anesthesia ,Hypoxia-Ischemia, Brain ,Ischemic preconditioning ,medicine.symptom ,business ,Research Article ,lcsh:RB1-214 - Abstract
Perinatal insults and subsequent neuroinflammation are the major mechanisms of neonatal brain injury, but there have been only scarce reports on the associations between hypoxic preconditioning and glial activation. Here we use neonatal hypoxia-ischemia brain injury model in 7-day-old rats andin vitrohypoxia model with primary mixed glial culture and the BV-2 microglial cell line to assess the effects of hypoxia and hypoxic preconditioning on glial activation. Hypoxia-ischemia brain insult induced significant brain weight reduction, profound cell loss, and reactive gliosis in the damaged hemisphere. Hypoxic preconditioning significantly attenuated glial activation and resulted in robust neuroprotection. As early as 2 h after the hypoxia-ischemia insult, proinflammatory gene upregulation was suppressed in the hypoxic preconditioning group.In vitroexperiments showed that exposure to 0.5% oxygen for 4 h induced a glial inflammatory response. Exposure to brief hypoxia (0.5 h) 24 h before the hypoxic insult significantly ameliorated this response. In conclusion, hypoxic preconditioning confers strong neuroprotection, possibly through suppression of glial activation and subsequent inflammatory responses after hypoxia-ischemia insults in neonatal rats. This might therefore be a promising therapeutic approach for rescuing neonatal brain injury.
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- 2015
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36. Role of spinal CXCL1 (GROα) in opioid tolerance: a human-to-rodent translational study
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Chih-Peng, Lin, Kai-Hsiang, Kang, Tzu-Hung, Lin, Ming-Yueh, Wu, Houng-Chi, Liou, Woei-Jer, Chuang, Wei-Zen, Sun, and Wen-Mei, Fu
- Subjects
Adult ,Male ,Chemokine CXCL1 ,Drug Tolerance ,Middle Aged ,Rats ,Analgesics, Opioid ,Rats, Sprague-Dawley ,Translational Research, Biomedical ,Animals ,Humans ,Female ,Injections, Spinal ,Aged ,Pain Measurement - Abstract
The pivotal role of glial activation and up-regulated inflammatory mediators in the opioid tolerance has been confirmed in rodents but not yet in humans. Here, the authors investigated the intraspinal cytokine and chemokine profiles of opioid-tolerant cancer patients; and to determine if up-regulated chemokines could modify opioid tolerance in rats.Cerebrospinal fluid samples from opioid-tolerant cancer patients and opioid-naive subjects were compared. The cerebrospinal fluid levels of tumor necrosis factor-alpha, CXCL1, CXCL10, CCL2, and CX3CL1 were assayed. The rat tail flick test was utilized to assess the effects of intrathecal CXCL1 on morphine-induced acute antinociception and analgesic tolerance.CXCL1 level in cerebrospinal fluid was significantly up-regulated in the opioid-tolerant group (n = 30, 18.8 pg/ml vs. 13.2 pg/ml, P = 0.02) and was positively correlated (r = 0.49, P0.01) with opioid dosage. In rat experiment, after induction of tolerance by morphine infusion, the spinal cord CXCL1 messenger RNA was up-regulated to 32.5 ± 11.9-fold. Although CXCL1 infusion alone did not affect baseline tail-flick latency, the analgesic efficacy of a single intraperitoneal injection of morphine dropped significantly on day 1 to day 3 after intrathecal infusion of CXCL1. After establishing tolerance by intrathecal continuous infusion of morphine, its development was accelerated by coadministration of CXCL1 and attenuated by coadministration of CXCL1-neutralizing antibody or CXCR2 antagonist.CXCL1 is up-regulated in both opioid-tolerant patients and rodents. The onset and extent of opioid tolerance was affected by antagonizing intrathecal CXCL1/CXCR2 signaling. Therefore, the CXCL1/CXCR2 signal pathway may be a novel target for the treatment of opioid tolerance.
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- 2014
37. Prostaglandin E2 Stimulates Fibronectin Expression through EP1 Receptor, Phospholipase C, Protein Kinase Cα, and c-Src Pathway in Primary Cultured Rat Osteoblasts
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Chih-Hsin Tang, Rong-Sen Yang, and Wen-Mei Fu
- Subjects
Integrins ,Indoles ,medicine.medical_treatment ,Oligonucleotides ,Integrin alpha5 ,Biochemistry ,Maleimides ,Bone Density ,Genes, Reporter ,Protein Isoforms ,Enzyme Inhibitors ,Estrenes ,Prostaglandin E2 ,Promoter Regions, Genetic ,Receptor ,Egtazic Acid ,Cells, Cultured ,Protein Kinase C ,Chelating Agents ,Genes, Dominant ,Reverse Transcriptase Polymerase Chain Reaction ,Integrin beta1 ,Immunohistochemistry ,Receptors, Prostaglandin E, EP1 Subtype ,Pyrrolidinones ,Up-Regulation ,src-Family Kinases ,lipids (amino acids, peptides, and proteins) ,Signal transduction ,Signal Transduction ,medicine.drug ,Prostaglandin E ,Proto-oncogene tyrosine-protein kinase Src ,Blotting, Western ,Immunoblotting ,Enzyme-Linked Immunosorbent Assay ,Biology ,Transfection ,Bone and Bones ,Dinoprostone ,medicine ,Animals ,Immunoprecipitation ,Receptors, Prostaglandin E ,RNA, Messenger ,Protein kinase A ,Molecular Biology ,Protein kinase C ,Osteoblasts ,Phospholipase C ,Cell Membrane ,Cell Biology ,Oligonucleotides, Antisense ,Cyclic AMP-Dependent Protein Kinases ,Molecular biology ,Fibronectins ,Rats ,Pyrimidines ,Microscopy, Fluorescence ,Type C Phospholipases ,Mutation ,Calcium - Abstract
Fibronectin (Fn) is involved in the early stages of bone formation, and prostaglandin E (PGE) is an important factor regulating osteogenesis. Here we found that PGE(2) enhanced extracellular Fn assembly in rat primary osteoblasts, as shown by immunofluorescence staining and enzyme-linked immunosorbent assay. PGE(2) also increased the protein levels of Fn by using Western blotting analysis. By using pharmacological inhibitors or activators or genetic inhibition by the EP receptor, antisense oligonucleotides revealed that the EP(1) receptor but not other PGE receptors is involved in PGE(2)-mediated up-regulation of Fn. At the mechanistic level, Ca(2+) chelator (1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis(acetoxymethyl ester)), phosphatidylinositol-phospholipase C inhibitor (U73122), or Src inhibitor (PP2) attenuated the PGE(2)-induced Fn expression. Protein kinase C (PKC) inhibitor (GF109203X) also inhibited the potentiating action of PGE(2). Furthermore, treatment with antisense oligonucleotides of various PKC isoforms, including alpha, beta, epsilon, and delta, demonstrated that alpha isozyme plays an important role in the enhancement action of PGE(2) on Fn assembly. Flow cytometry and reverse transcription-PCR showed that PGE(2) and 17-phenyl trinor PGE(2) (EP(1)/EP(3) agonist) increased the surface expression and mRNA level of alpha5 or beta1 integrins. Fn promoter activity was enhanced by PGE(2) and 17-phenyl trinor PGE(2) in cells transfected with pGL2F1900-Luc. Cotransfection with dominant negative mutants of PKCalpha or c-Src inhibited the potentiating action of PGE(2) on Fn promoter activity. Local administration of PGE(2) or 17-phenyl trinor PGE(2) into the metaphysis of the tibia via the implantation of a needle cannula significantly increased the Fn and alpha5beta1 integrin immunostaining and bone volume of secondary spongiosa in tibia. Taken together, our results provided evidence that PGE(2) increased Fn and promoted bone formation in rat osteoblasts via the EP(1)/phospholipase C/PKCalpha/c-Src signaling pathway.
- Published
- 2005
38. Enhancement of learning behaviour by a potent nitric oxide-guanylate cyclase activator YC-1
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Wen-Mei Fu, Keng-Chen Liang, Wei-Lin Chien, Che-Ming Teng, Fang-Yu Lee, and Sheng-Chu Kuo
- Subjects
Indazoles ,Enzyme Activators ,Morris water navigation task ,Stimulation ,Water maze ,Pharmacology ,Nitric Oxide ,Nitric oxide ,chemistry.chemical_compound ,Reaction Time ,medicine ,Animals ,Learning ,Rats, Wistar ,Nootropic Agents ,General Neuroscience ,Excitatory Postsynaptic Potentials ,Muscarinic antagonist ,Long-term potentiation ,Rats ,chemistry ,Guanylate Cyclase ,Anesthesia ,Synaptic plasticity ,cGMP-dependent protein kinase ,medicine.drug - Abstract
Memory is one of the most fundamental mental processes, and various approaches have been used to understand the mechanisms underlying this process. Nitric oxide (NO), cGMP and protein kinase G (PKG) are involved in the modulation of synaptic plasticity in various brain regions. YC-1, which is a benzylindazole derivative, greatly potentiated the response of soluble guanylate cyclase to NO (up to several hundreds fold). We have previously shown that YC-1 markedly enhances long-term potentiation in hippocampal and amygdala slices via NO-cGMP-PKG-dependent pathway. We here further investigated whether YC-1 promotes learning behaviour in Morris water maze and avoidance tests. It was found that YC-1 shortened the escape latency in the task of water maze, increased and decreased the retention scores in passive and active avoidance task, respectively. Administration of YC-1 30 min after foot-shock stimulation did not significantly affect retention scores in response to passive avoidance test. Administration of scopolamine, a muscarinic antagonist, markedly impaired the memory acquisition. Pretreatment of YC-1 inhibited the scopolamine-induced learning deficit. The enhancement of learning behaviour by YC-1 was antagonized by intracerebroventricular injection of NOS inhibitor L-NAME and PKG inhibitors of KT5823 and Rp-8-Br-PET-cGMPS, indicating that NO-cGMP-PKG pathway is also involved in the learning enhancement action of YC-1. YC-1 is thus a good drug candidate for the improvement of learning and memory.
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- 2005
39. Signal transduction for inhibition of inducible nitric oxide synthase and cyclooxygenase-2 induction by capsaicin and related analogs in macrophages
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Wen-Mei Fu, Feng-Ming Ho, Sho Tone Lee, Ching-Wen Chen, Wan-Wan Lin, and Wen Tung Wu
- Subjects
Pharmacology ,MAPK/ERK pathway ,biology ,Resiniferatoxin ,TRPV1 ,Molecular biology ,Vanilloids ,Nitric oxide synthase ,chemistry.chemical_compound ,chemistry ,Capsaicin ,biology.protein ,lipids (amino acids, peptides, and proteins) ,Signal transduction ,Capsazepine - Abstract
Although capsaicin analogs might be a potential strategy to manipulate inflammation, the mechanism is still unclear. In this study, the effects and action mechanisms of vanilloid analogs on iNOS and COX-2 expression were investigated in RAW264.7 macrophages. Capsaicin and resiniferatoxin (RTX) can inhibit LPS- and IFN-γ-mediated NO production, and iNOS protein and mRNA expression with similar IC50 values of around 10 μM. Capsaicin also transcriptionally inhibited LPS- and PMA-induced COX-2 expression and PGE2 production. However, this effect exhibited a higher potency (IC50: 0.2 μM), and RTX failed to elicit such responses at 10 μM. Interestingly, we found that capsazepine, a competitive TRPV1 antagonist, did not prevent the inhibition elicited by capsaicin or RTX. Nevertheless, it mimicked vanilloids in inhibiting iNOS/NO and COX-2/PGE2 induction with an IC50 value of 3 μM. RT–PCR and immunoblotting analysis excluded the expression of TRPV1 in RAW264.7 macrophages. The DNA binding assay demonstrated the abilities of vanilloids to inhibit LPS-elicited NF-κB and AP-1 activation and IFN-γ-elicited STAT1 activation. The reporter assay of AP-1 activity also supported this action. The kinase assay indicated that ERK, JNK, and IKK activation by LPS were inhibited by vanilloids. In conclusion, vanilloids can modulate the expression of inflammatory iNOS and COX-2 genes in macrophages through interference with upstream signalling events of LPS and IFN-γ. These findings provide new insights into the potential benefits of the active ingredient in hot chilli peppers in inflammatory conditions. British Journal of Pharmacology (2003) 140, 1077–1087. doi:10.1038/sj.bjp.0705533
- Published
- 2003
40. Enhancement of Long-Term Potentiation by a Potent Nitric Oxide-Guanylyl Cyclase Activator, 3-(5-Hydroxymethyl-2-furyl)-1-benzyl-indazole
- Author
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Sheng-Chu Kuo, Wen-Mei Fu, Che-Ming Teng, Keng-Chen Liang, Wei-Lin Chien, and Fang-Yu Lee
- Subjects
Male ,Nitroprusside ,Indazoles ,Long-Term Potentiation ,Enzyme Activators ,Pharmacology ,Nitric Oxide ,CREB ,Synaptic Transmission ,medicine ,Animals ,Nitric Oxide Donors ,Rats, Wistar ,Protein kinase A ,Neuronal Plasticity ,biology ,Chemistry ,Long-term potentiation ,Immunohistochemistry ,Rats ,Electrophysiology ,Enzyme Activation ,Metabotropic receptor ,Biochemistry ,Guanylate Cyclase ,biology.protein ,Molecular Medicine ,Sodium nitroprusside ,Signal transduction ,Tetanic stimulation ,Soluble guanylyl cyclase ,medicine.drug - Abstract
Nitric oxide (NO) is known to affect synaptic plasticity in various regions of the brain via the cGMP-cGMP-dependent protein kinase (PKG) pathway. We found that a novel compound 3-(5-hydroxymethyl-2-furyl)-1-benzyl-indazole (YC-1), a drug known to modulate the response of soluble guanylyl cyclase to NO, greatly potentiates long-term potentiation (LTP). This compound markedly enhanced the induction of LTP in rat hippocampal and amygdala slices by weak tetanic stimulation. The potentiation of LTP by YC-1 was greatly reduced by NO synthase inhibitor Ng-nitro-l-arginine-methylester, guanylyl cyclase inhibitor 1 H-[1,2,4]-oxadiazolo(4,3-a)-quinoxalin-1-one, and PKG inhibitor (9S,10R,12R)-2,3,9,10,11,12, hexahydro-10-methoxy-2,9-dimethyl-1-ox0-9.12-epoxy-1H-diindolo[1,2,3-fg:3',2',1'-kl]pyrrolo[3,4-I][1,6]benzodiazocine-10-carboxylic acid methyl ester (KT5823). In addition, mitogen-activated protein kinase kinase inhibitor 2'-amino-3'-methoxyflavone (PD98059) also markedly inhibited LTP potentiating action of YC-1. Intracellular increase of Ca2+ concentration derived from N-methyl-d-aspartate and glutamate metabotropic receptors contributes to the potentiating action of YC-1. Concurrent perfusion of YC-1 and NO donor sodium nitroprusside for a short time period resulted in the induction of LTP by stimuli at a frequency as low as 0.02 Hz. Incubation of unstimulated hippocampal slices with YC-1 plus nitroprusside increased the immunofluorescence of phospho-extracellular signal-regulated kinase (ERK) and phospho-cAMP response element binding protein (CREB). Furthermore, the Western blot shows that the phosphorylation of ERKs 1 and 2 and CREB of unstimulated hippocampal slices was increased by YC-1 plus nitroprusside, which was inhibited by KT5823. The NO-cGMP-PKG-ERK signaling pathway thus plays important role in the potentiation of LTP by YC-1.
- Published
- 2003
41. Antagonism of proteasome inhibitor-induced heme oxygenase-1 expression by PINK1 mutation
- Author
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Wei-Lin Chien, Xiang-Jun Sheng, Horng-Huei Liou, Hunag-Ju Tu, Ming-Jen Lee, Dai-Hua Lu, Kai-Hsiang Kang, and Wen-Mei Fu
- Subjects
Male ,0301 basic medicine ,Leupeptins ,lcsh:Medicine ,Mitochondrion ,Biochemistry ,chemistry.chemical_compound ,0302 clinical medicine ,Animal Cells ,Cellular stress response ,MG132 ,Medicine and Health Sciences ,Small interfering RNAs ,lcsh:Science ,Energy-Producing Organelles ,Neurons ,Movement Disorders ,Multidisciplinary ,Cell Death ,Brain ,Neurodegenerative Diseases ,Parkinson Disease ,Neurochemistry ,Up-Regulation ,Mitochondria ,Substantia Nigra ,Nucleic acids ,Protein Transport ,Neurology ,Anatomy ,Cellular Structures and Organelles ,Cellular Types ,Neurochemicals ,Proteasome Inhibitors ,Signal Transduction ,Research Article ,medicine.drug ,NF-E2-Related Factor 2 ,PINK1 ,Bioenergetics ,Biology ,Transfection ,Models, Biological ,Gene Expression Regulation, Enzymologic ,Cell Line ,03 medical and health sciences ,Genetics ,medicine ,Animals ,Humans ,Rats, Wistar ,Non-coding RNA ,Protein kinase B ,Cell Nucleus ,lcsh:R ,Biology and Life Sciences ,Proteins ,Protein Complexes ,Proteasomes ,Cell Biology ,Molecular biology ,Antioxidant Response Elements ,Gene regulation ,Heme oxygenase ,030104 developmental biology ,chemistry ,Proteasome ,Cellular Neuroscience ,Mutation ,Proteasome inhibitor ,RNA ,Mutant Proteins ,lcsh:Q ,Gene expression ,Protein Kinases ,Dopaminergics ,Heme Oxygenase-1 ,030217 neurology & neurosurgery ,Neuroscience - Abstract
PTEN-induced putative kinase 1 (PINK1) is an integral protein in the mitochondrial membrane and maintains mitochondrial fidelity. Pathogenic mutations in PINK1 have been identified as a cause of early-onset autosomal recessive familial Parkinson’s disease (PD). The ubiquitin proteasome pathway is associated with neurodegenerative diseases. In this study, we investigated whether mutations of PINK1 affects the cellular stress response following proteasome inhibition. Administration of MG132, a peptide aldehyde proteasome inhibitor, significantly increased the expression of heme oxygenase-1 (HO-1) in rat dopaminergic neurons in the substantia nigra and in the SH-SY5Y neuronal cell line. The induction of HO-1 expression by proteasome inhibition was reduced in PINK1 G309D mutant cells. MG132 increased the levels of HO-1 through the Akt, p38, and Nrf2 signaling pathways. Compared with the cells expressing WT-PINK1, the phosphorylation of Akt and p38 was lower in those cells expressing the PINK1 G309D mutant, which resulted in the inhibition of the nuclear translocation of Nrf2. Furthermore, MG132-induced neuronal death was enhanced by the PINK1 G309D mutation. In this study, we demonstrated that the G309D mutation impairs the neuroprotective function of PINK1 following proteasome inhibition, which may be related to the pathogenesis of PD.
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- 2017
42. Short-time focused ultrasound hyperthermia enhances liposomal doxorubicin delivery and antitumor efficacy for brain metastasis of breast cancer
- Author
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Tzu-Hung Lin, Win-Li Lin, Chi-Feng Chiang, Houng-Chi Liou, Yu-Hone Hsu, Wen-Mei Fu, and Sheng-Kai Wu
- Subjects
Hyperthermia ,Pathology ,medicine.medical_specialty ,focused ultrasound (FUS) ,Ultrasonic Therapy ,Biophysics ,Pharmaceutical Science ,Antineoplastic Agents ,Apoptosis ,Breast Neoplasms ,Bioengineering ,Polyethylene Glycols ,Biomaterials ,Mice ,Breast cancer ,International Journal of Nanomedicine ,Cell Line, Tumor ,brain metastasis of breast cancer ,Drug Discovery ,In Situ Nick-End Labeling ,medicine ,Animals ,Doxorubicin ,Cell Proliferation ,Original Research ,Drug Carriers ,Mice, Inbred BALB C ,Microbubbles ,Brain Neoplasms ,Cell growth ,business.industry ,Organic Chemistry ,Brain ,Hyperthermia, Induced ,General Medicine ,hyperthermia ,medicine.disease ,Cancer research ,Nanoparticles ,Immunohistochemistry ,Female ,lipids (amino acids, peptides, and proteins) ,business ,pegylated liposomal doxorubicin (PLD) ,medicine.drug ,Brain metastasis - Abstract
Sheng-Kai Wu,1 Chi-Feng Chiang,1 Yu-Hone Hsu,1,4 Tzu-Hung Lin,2 Houng-Chi Liou,2 Wen-Mei Fu,2 Win-Li Lin1,3 1Institute of Biomedical Engineering, College of Medicine and College of Engineering, 2Institute of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan; 3Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, Taiwan; 4Department of Neurosurgery, Cheng-Hsin General Hospital, Taipei, Taiwan Abstract: The blood–brain/tumor barrier inhibits the uptake and accumulation of chemotherapeutic drugs. Hyperthermia can enhance the delivery of chemotherapeutic agent into tumors. In this study, we investigated the effects of short-time focused ultrasound (FUS) hyperthermia on the delivery and therapeutic efficacy of pegylated liposomal doxorubicin (PLD) for brain metastasis of breast cancer. Murine breast cancer 4T1-luc2 cells expressing firefly luciferase were injected into female BALB/c mice striatum tissues and used as a brain metastasis model. The mice were intravenously injected with PLD (5 mg/kg) with/without 10-minute transcranial FUS hyperthermia on day 6 after tumor implantation. The amounts of doxorubicin accumulated in the normal brain tissues and tumor tissues with/without FUS hyperthermia were measured using fluorometry. The tumor growth for the control, hyperthermia, PLD, and PLD + hyperthermia groups was measured using an IVIS spectrum system every other day from day 3 to day 11. Cell apoptosis and tumor characteristics were assessed using immunohistochemistry. Short-time FUS hyperthermia was able to significantly enhance the PLD delivery into brain tumors. The tumor growth was effectively inhibited by a single treatment of PLD + hyperthermia compared with both PLD alone and short-time FUS hyperthermia alone. Immunohistochemical examination further demonstrated the therapeutic efficacy of PLD plus short-time FUS hyperthermia for brain metastasis of breast cancer. The application of short-time FUS hyperthermia after nanodrug injection may be an effective approach to enhance nanodrug delivery and improve the treatment of metastatic cancers. Keywords: hyperthermia, focused ultrasound (FUS), pegylated liposomal doxorubicin (PLD), brain metastasis of breast cancer
- Published
- 2014
43. Osteopontin upregulates the expression of glucose transporters in osteosarcoma cells
- Author
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Wen-Mei Fu, I-Shan Hsieh, and Rong-Sen Yang
- Subjects
Glucose uptake ,Glucose Transport Proteins, Facilitative ,lcsh:Medicine ,chemistry.chemical_compound ,Medicine and Health Sciences ,Osteopontin ,lcsh:Science ,Etoposide ,Osteosarcoma ,Glucose Transporter Type 1 ,Multidisciplinary ,Glucose Transporter Type 3 ,biology ,Pharmaceutics ,Sarcomas ,Up-Regulation ,Oncology ,Phloretin ,Cancer Therapy ,Fluorouracil ,Research Article ,musculoskeletal diseases ,medicine.medical_specialty ,Antineoplastic Agents ,Bone Neoplasms ,Drug Therapy ,Downregulation and upregulation ,Cell Line, Tumor ,Membrane Transport Modulators ,Internal medicine ,medicine ,Chemotherapy ,Humans ,business.industry ,Daunorubicin ,lcsh:R ,Glucose transporter ,Cancers and Neoplasms ,Integrin alphaVbeta3 ,medicine.disease ,Methotrexate ,Endocrinology ,chemistry ,Apoptosis ,Cancer research ,biology.protein ,lcsh:Q ,business ,Combination Chemotherapy - Abstract
Osteosarcoma is the most common primary malignancy of bone. Even after the traditional standard surgical therapy, metastasis still occurs in a high percentage of patients. Glucose is an important source of metabolic energy for tumor proliferation and survival. Tumors usually overexpress glucose transporters, especially hypoxia-responsive glucose transporter 1 and glucose transporter 3. Osteopontin, hypoxia-responsive glucose transporter 1, and glucose transporter 3 are overexpressed in many types of tumors and have been linked to tumorigenesis and metastasis. In this study, we investigated the regulation of glucose transporters by osteopontin in osteosarcoma. We observed that both glucose transporters and osteopontin were upregulated in hypoxic human osteosarcoma cells. Endogenously released osteopontin regulated the expression of glucose transporter 1 and glucose transporter 3 in osteosarcoma and enhanced glucose uptake into cells via the αvβ3 integrin. Knockdown of osteopontin induced cell death in 20% of osteosarcoma cells. Phloretin, a glucose transporter inhibitor, also caused cell death by treatment alone. The phloretin-induced cell death was significantly enhanced in osteopontin knockdown osteosarcoma cells. Combination of a low dose of phloretin and chemotherapeutic drugs, such as daunomycin, 5-Fu, etoposide, and methotrexate, exhibited synergistic cytotoxic effects in three osteosarcoma cell lines. Inhibition of glucose transporters markedly potentiated the apoptotic sensitivity of chemotherapeutic drugs in osteosarcoma. These results indicate that the combination of a low dose of a glucose transporter inhibitor with cytotoxic drugs may be beneficial for treating osteosarcoma patients.
- Published
- 2014
44. 5-Lipoxygenase inhibitors attenuate TNF-α-induced inflammation in human synovial fibroblasts
- Author
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Yung-Cheng Chiu, Mann-Jen Hour, Ming-Yueh Wu, Rong-Sen Yang, Chih-Hsin Tang, Houng-Chi Liou, Huang-Ju Tu, Wen-Mei Fu, Han-Ching Lin, and Tzu-Hung Lin
- Subjects
Male ,Chemokine ,Inflammatory arthritis ,medicine.medical_treatment ,Arthritis ,lcsh:Medicine ,Gene Knockout Techniques ,Mice ,Medicine and Health Sciences ,Edema ,Inflammatory Arthritis ,Lipoxygenase Inhibitors ,Phosphorylation ,RNA, Small Interfering ,lcsh:Science ,Chemokine CCL2 ,Innate Immune System ,Multidisciplinary ,Synovial Membrane ,I-kappa B Kinase ,Cytokine ,medicine.anatomical_structure ,Arachidonate 5-lipoxygenase ,Cytokines ,Tumor necrosis factor alpha ,RNA Interference ,medicine.symptom ,Research Article ,Immunology ,Inflammation ,Biology ,Leukotriene B4 ,Rheumatology ,medicine ,Animals ,Humans ,Arachidonate 5-Lipoxygenase ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,Interleukins ,lcsh:R ,Biology and Life Sciences ,Fibroblasts ,Molecular Development ,medicine.disease ,Enzyme Activation ,Mice, Inbred C57BL ,Immune System ,Proteolysis ,Cancer research ,biology.protein ,lcsh:Q ,Synovial membrane ,Developmental Biology - Abstract
The lipoxygenase isoform of 5-lipoxygenase (5-LOX) is reported to be overexpressed in human rheumatoid arthritis synovial tissue and involved in the progress of inflammatory arthritis. However, the detailed mechanism of how 5-lipoxygenase regulates the inflammatory response in arthritis synovial tissue is still unclear. The aim of this study was to investigate the involvement of lipoxygenase pathways in TNF-α-induced production of cytokines and chemokines. Human synovial fibroblasts from rheumatoid patients were used in this study. 5-LOX inhibitors and shRNA were used to examine the involvement of 5-LOX in TNF-α-induced cytokines and chemokines expression. The signaling pathways were examined by Western Blotting or immunofluorescence staining. The effect of 5-LOX inhibitor on TNF-α-induced chemokine expression and paw edema was also explored in vivo in C57BL/6 mice. Treatment with 5-LOX inhibitors significantly decreased TNF-α-induced pro-inflammatory mediators including interleukin-6 (IL-6) and monocyte chemo-attractant protein-1 (MCP-1) in human synovial fibroblasts. Knockdown of 5-LOX using shRNA exerted similar inhibitory effects. The abrogation of NF-κB activation was involved in the antagonizing effects of these inhibitors. Furthermore, 5-LOX inhibitor decreased TNF-α-induced up-regulation of serum MCP-1 level and paw edema in mouse model. Our results provide the evidence that the administration of 5-LOX inhibitors is able to ameliorate TNF-α-induced cytokine/chemokine release and paw edema, indicating that 5-LOX inhibitors may be developed for therapeutic treatment of inflammatory arthritis.
- Published
- 2014
45. Target‐dependent regulation of acetylcholine secretion at developing motoneurons in Xenopus cell cultures
- Author
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Jau-Cheng Liou, Wen-Mei Fu, and Yu-Hwa Chen
- Subjects
endocrine system ,Embryo, Nonmammalian ,Patch-Clamp Techniques ,Time Factors ,Physiology ,Xenopus ,Neuromuscular Junction ,Tubocurarine ,Nerve Tissue Proteins ,Biology ,Synaptic Transmission ,Neuromuscular junction ,Synapse ,Acetylcholine secretion ,Neurotrophin 3 ,Postsynaptic potential ,Neurites ,medicine ,Animals ,Myocyte ,Ciliary Neurotrophic Factor ,Nerve Growth Factors ,Axon ,Cells, Cultured ,Motor Neurons ,Veratridine ,Muscles ,musculoskeletal, neural, and ocular physiology ,Original Articles ,Acetylcholine ,Axons ,Coculture Techniques ,Cell biology ,Kinetics ,medicine.anatomical_structure ,nervous system ,Synapses ,Quantum Theory ,Neuron ,Neuroscience ,medicine.drug - Abstract
1. Myocyte-dependent regulation of acetylcholine (ACh) quantal secretion from developing motoneurons was studied in day-3 Xenopus nerve-muscle co-cultures. Spontaneous synaptic currents (SSCs) were measured in manipulated synapses by using whole-cell voltage-clamped myocytes. Changes in SSC amplitude were assumed to reflect changes in the ACh content of secreted quantal packets. Compared with natural synapses, motoneurons without any contact with a myocyte (naive neurons) released ACh in smaller quantal packets. 2. Bipolar cultured motoneurons, which were in contact with a myocyte with one axon branch (contact-end) but remained free at another axon branch (free-end), were further used to examine quantal ACh secretion. The ACh quantal size recorded at free-end terminals was similar to that of naive neurons and was smaller than that at the contact-end, indicating that myocyte contact exerts differential regulation on quantal secretion in the same neuron. 3. Some of the neurons that formed a natural synapse with a myocyte continued to grow forward and ACh quantal secretion from the free growth cone was examined. The ACh quantal size recorded at free growth cones was inversely proportional to the distance to the natural synapse, implying localized regulation of quantal secretion by the myocyte. 4. Chronic treatment of day-1 cultures with veratridine and d-tubocurarine, respectively, increased and decreased the neurotrophic action of myocytes when assayed on day 3. 5. Taken together, these findings suggest that the myocyte is an important postsynaptic target in the regulation of quantal secretion and that the trophic action is spatially restricted to the neighbourhood of the neuromuscular junction.
- Published
- 1999
46. Nerve Terminal Currents Induced by Autoreception of Acetylcholine Release
- Author
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Yu-Hwa Chen, Wen-Mei Fu, and Houng-Chi Liou
- Subjects
Atropine ,Nicotine ,N-Methylaspartate ,Patch-Clamp Techniques ,Xenopus ,Presynaptic Terminals ,Muscarinic Antagonists ,Nicotinic Antagonists ,Receptors, Nicotinic ,Neurotransmission ,Hexamethonium ,Synaptic Transmission ,Article ,chemistry.chemical_compound ,Excitatory Amino Acid Agonists ,medicine ,Animals ,Nicotinic Agonists ,Autoreceptors ,Membrane potential ,General Neuroscience ,Depolarization ,Acetylcholine ,Nicotinic agonist ,chemistry ,Biophysics ,Autoreceptor ,NMDA receptor ,Calcium ,Neuroscience ,medicine.drug - Abstract
The activation of autoreceptors is known to be important in the modulation of presynaptic transmitter secretion in peripheral and central neurons. Using whole-cell recordings made from the free growth cone of myocyte-contact motoneurons ofXenopuscell cultures, we have observed spontaneous nerve terminal currents (NTCs). These spontaneous NTCs are blocked by d-tubocurarine (d-TC) and α-bungarotoxin (α-BuTx), indicating that endogenously released acetylcholine (ACh) can produce substantial membrane depolarization in the nerve terminals. Local application of NMDA to the growth cone increased the frequency of spontaneous NTCs. When the electrical stimulations were applied at the soma to initiate evoked-release of ACh, evoked ACh-induced potentials were recorded in the nerve terminals, which were inhibited by d-TC and hexamethonium but not by atropine. Replacement of normal Ringer’s solution with high-Mg2+, low-Ca2+solution also reversibly inhibited evoked ACh-induced potentials. The possible regulatory role of presynaptic nicotinic autoreceptors on the synaptic transmission was also examined. When the innervated myocyte was whole-cell voltage-clamped to record synaptic currents, application of hexamethonium inhibited the amplitude of evoked synaptic currents at a higher degree than that of iontophoretic ACh-induced currents. Furthermore, hexamethonium markedly reduced the frequency of spontaneous synaptic currents at high-activity synapses. Pretreatment of neurons with α-BuTx also inhibited the evoked synaptic currents in manipulated synapses. These results suggest that ACh released spontaneously or by electrical stimulation may act on the presynaptic nicotinic autoreceptors of the same nerve terminals to produce membrane potential change and to regulate synaptic transmission.
- Published
- 1998
47. Regulation of Presynaptic NMDA Responses by External and Intracellular pH Changes at Developing Neuromuscular Synapses
- Author
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Yu-Hwa Chen, Wen-Mei Fu, and Mei-Lin Wu
- Subjects
N-Methylaspartate ,Xenopus ,Intracellular pH ,Neuromuscular Junction ,Presynaptic Terminals ,Endogeny ,Acetates ,Alkalies ,Receptors, N-Methyl-D-Aspartate ,Article ,Cytosol ,Excitatory Amino Acid Agonists ,Animals ,Myocyte ,Peripheral Nerves ,Muscle, Skeletal ,Cells, Cultured ,Motor Neurons ,Chemistry ,General Neuroscience ,Hydrogen-Ion Concentration ,Electrophysiology ,nervous system ,Biochemistry ,Second messenger system ,Synaptic plasticity ,Biophysics ,NMDA receptor ,Calcium ,Propionates ,Extracellular Space ,Acids ,Intracellular - Abstract
NMDA receptors play important roles in synaptic plasticity and neuronal development. The functions of NMDA receptors are modulated by many endogenous substances, such as external pH (pHe), as well as second messenger systems. In the present study, the nerve–muscle cocultures ofXenopusembryos were used to investigate the effects of both external and intracellular pH (pHi) changes on the functional responses of presynaptic NMDA receptors. Spontaneous synaptic currents (SSCs) were recorded from innervated myocyte using whole-cell recordings. Local perfusion of NMDA at synaptic regions increased the SSC frequency via the activation of presynaptic NMDA receptors. A decrease in pHefrom 7.6 to 6.6 reduced NMDA responses to 23% of the control, and an increase in pHefrom 7.6 to 8.6 potentiated the NMDA responses in increasing SSC frequency. The effect of NMDA on intracellular Ca2+concentration ([Ca2+]i) was also affected by pHechanges: external acidification inhibited and alkalinization potentiated [Ca2+]iincreases induced by NMDA. Intracellular pH changes of single soma were measured by ratio fluorometric method using 2,7-bis (carboxyethyl)-5,6-carboxyfluorescein (BCECF). Cytosolic acidification was used in which NaCl in Ringer’s solution was replaced with weak organic acids. Acetate and propionate but not methylsulfate substitution caused intracellular acidification and potentiated NMDA responses in increasing SSC frequency, intracellular free Ca2+concentration, and NMDA-induced currents. On the other hand, cytosolic alkalinization with NH4Cl did not significantly affect these NMDA responses. These results suggest that the functions of NMDA receptors are modulated by both pHeand pHichanges, which may occur in some physiological or pathological conditions.
- Published
- 1998
48. Studies on Neuromuscular Blockade by Boldine in the Mouse Phrenic Nerve-Diaphragm
- Author
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Wen-Mei Fu, Yu Wen Cheng, and Jaw Jou Kang
- Subjects
Male ,Aporphines ,Contraction (grammar) ,End-plate potential ,Diaphragm ,Neuromuscular transmission ,Pharmacology ,Cholinergic Antagonists ,Mice ,chemistry.chemical_compound ,Postsynaptic potential ,medicine ,Animals ,Boldine ,Evoked Potentials ,Phrenic nerve ,Mice, Inbred ICR ,Neuromuscular Blockade ,Chemistry ,musculoskeletal system ,Acetylcholine ,Neostigmine ,Phrenic Nerve ,Neuromuscular Depolarizing Agents ,Anesthesia ,Female ,Muscle Contraction ,medicine.drug - Abstract
The effects of boldine [(S)-2,9-dihydroxyl-1,10-dimethoxy-aporphine], a major alkaloid in the leaves and bark of Boldo (Peumus boldus Mol.), on neuromuscular transmission were studied using a muscle phrenic-nerve diaphragm preparation. Boldine at concentrations lower than 200 microM preferentially inhibited, after an initial period of twitch augmentation, the nerve-evoked twitches of the mouse diaphragm and left the muscle-evoked twitches unaffected. The twitch inhibition could be restored by neostigmine or washout with Krebs solution. The twitches evoked indirectly and directly were both augmented initially, suggesting that the twitch augmentation induced by boldine was myogenic. Boldine inhibited the acetylcholine-induced contraction of denervated diaphragm dose-dependently with an IC50 value of 13.5 microM. At 50 microM, boldine specifically inhibited the amplitude of the miniature end plate potential. In addition, boldine was similar to d-tubocurarine in its action to reverse the neuromuscular blocking action of alpha-bungarotoxin. These results showed that the neuromuscular blockade by boldine on isolated mouse phrenic-nerve diaphragm might be due to its direct interaction with the postsynaptic nicotinic acetylcholine receptor.
- Published
- 1998
49. Autism-associated gene Dlgap2 mutant mice demonstrate exacerbated aggressive behaviors and orbitofrontal cortex deficits
- Author
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Li-Feng Jiang-Xie, Shih-Yin Ho, Susan Shur-Fen Gau, Dai-Hua Lu, Hsiao-Mei Liao, Wen-Mei Fu, Horng-Huei Liou, Li-Jen Lee, Chia-Hsiang Chen, and Yuh-Tarng Chen
- Subjects
Scaffold protein ,business.industry ,Research ,mouse model ,medicine.disease ,orbitofrontal cortex, autism ,Dlgap2 ,Synapse ,Psychiatry and Mental health ,Electrophysiology ,Developmental Neuroscience ,synapse ,Excitatory postsynaptic potential ,Medicine ,Autism ,Orbitofrontal cortex ,business ,aggressive behavior ,Molecular Biology ,Postsynaptic density ,Neuroscience ,Developmental Biology ,Social behavior - Abstract
Background As elegant structures designed for neural communication, synapses are the building bricks of our mental functions. Recently, many studies have pointed out that synaptic protein-associated mutations may lead to dysfunctions of social cognition. Dlgap2, which encodes one of the main components of scaffold proteins in postsynaptic density (PSD), has been addressed as a candidate gene in autism spectrum disorders. To elucidate the disturbance of synaptic balance arising from Dlgap2 loss-of-function in vivo, we thus generated Dlgap2 −/− mice to investigate their phenotypes of synaptic function and social behaviors. Methods The creation of Dlgap2 −/− mice was facilitated by the recombineering-based method, Cre-loxP system and serial backcross. Reversal learning in a water T-maze was used to determine repetitive behaviors. The three-chamber approach task, resident–intruder test and tube task were performed to characterize the social behaviors of mutant mice. Cortical synaptosomal fraction, Golgi-Cox staining, whole-cell patch electrophysiology and transmission electron microscopy were all applied to investigate the function and structure of synapses in the orbitofrontal cortex (OFC) of Dlgap2 −/− mice. Results Dlgap2 −/− mice displayed exacerbated aggressive behaviors in the resident–intruder task, and elevated social dominance in the tube test. In addition, Dlgap2 −/− mice exhibited a clear reduction of receptors and scaffold proteins in cortical synapses. Dlgap2 −/− mice also demonstrated lower spine density, decreased peak amplitude of miniature excitatory postsynaptic current and ultra-structural deficits of PSD in the OFC. Conclusions Our findings clearly demonstrate that Dlgap2 plays a vital role in social behaviors and proper synaptic functions of the OFC. Moreover, these results may provide valuable insights into the neuropathology of autism.
- Published
- 2013
50. Targeted delivery of erythropoietin by transcranial focused ultrasound for neuroprotection against ischemia/reperfusion-induced neuronal injury: a long-term and short-term study
- Author
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Win-Li Lin, Ming-Tao Yang, Wen-Mei Fu, Kai-Hsiang Kang, Houng-Chi Liou, Sheng-Kai Wu, and Dai-Hua Lu
- Subjects
Male ,lcsh:Medicine ,Vascular permeability ,Pharmacology ,Cardiovascular ,Brain Ischemia ,Brain ischemia ,Drug Delivery Systems ,Engineering ,lcsh:Science ,Gait ,Neurons ,Multidisciplinary ,Microbubbles ,Behavior, Animal ,Infarction, Middle Cerebral Artery ,Animal Models ,Stroke ,Neuroprotective Agents ,Sound ,Blood-Brain Barrier ,Anesthesia ,Reperfusion Injury ,Middle cerebral artery ,Medicine ,medicine.symptom ,medicine.drug ,Research Article ,Biotechnology ,Drugs and Devices ,animal structures ,Ischemia ,Biomedical Engineering ,Bioengineering ,Brain damage ,Neuroprotection ,Medical Devices ,Model Organisms ,medicine.artery ,medicine ,Animals ,Rats, Wistar ,Erythropoietin ,Biology ,business.industry ,lcsh:R ,medicine.disease ,Rats ,Rat ,lcsh:Q ,business ,Reperfusion injury - Abstract
Erythropoietin (EPO) is a neuroprotective agent against cerebral ischemia/reperfusion (I/R)-induced brain injury. However, its crossing of blood-brain barrier is limited. Focused ultrasound (FUS) sonication with microbubbles (MBs) can effectively open blood-brain barrier to boost the vascular permeability. In this study, we investigated the effects of MBs/FUS on extending the therapeutic time window of EPO and its neuroprotective effects in both acute and chronic phases. Male Wistar rats were firstly subjected to two common carotid arteries and right middle cerebral artery occlusion (three vessels occlusion, 3VO) for 50 min, and then the rats were treated with hEPO (human recombinant EPO, 5000 IU/kg) with or without MBs/FUS at 5 h after occlusion/reperfusion. Acute phase investigation (I/R, I/R+MBs/FUS, I/R+hEPO, and I/R+hEPO+MBs/FUS) was performed 24 h after I/R; chronic tests including cylinder test and gait analysis were performed one month after I/R. The experimental results showed that MBs/FUS significantly increased the cerebral content of EPO by bettering vascular permeability. In acute phase, both significant improvement of neurological score and reduction of infarct volume were found in the I/R+hEPO+MBs/FUS group, as compared with I/R and I/R+hEPO groups. In chronic phase, long-term behavioral recovery and neuronal loss in brain cortex after I/R injury was significantly improved in the I/R+hEPO+MBs/FUS group. This study indicates that hEPO administration with MBs/FUS sonication even at 5 h after occlusion/reperfusion can produce a significant neuroprotection.
- Published
- 2013
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