Search

Parkinson’s disease (PD) is one of the most widespread neurodegenerative diseases. However, the currently available treatments could only relieve symptoms. Novel therapeutic targets are urgently needed. Several previous studies mentioned that protein tyrosine phosphatase 1B (PTP1B) acted as a negative regulator of the insulin signal pathway and played a significant role in the inflammation process. However, few studies have investigated the role of PTP1B in the central nervous system. Our study showed that suramin, an inhibitor of PTP1B, could improve neuronal damage. It could significantly attenuate the interferon-gamma-induced upregulation of proinflammatory cytokines, including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). It enhanced M2 type microglia markers, such as arginase-1 and Ym-1 in BV2 murine microglial cells. PTP1B inhibition also reversed 6-hydroxydopamine- (6-OHDA-) induced downregulation of phospho-cAMP response element-binding protein (p-CREB) and brain-derived neurotrophic factor (BDNF) in SH-SY5Y cells. Besides, we knocked down and overexpressed PTP1B in the SH-SY5Y cells to confirm its role in neuroprotection. We also verified the effect of suramin in the zebrafish PD model. Treatment with suramin could significantly reverse 6-OHDA-induced locomotor deficits and improved tyrosine hydroxylase (TH) via attenuating endoplasmic reticulum (ER) stress biomarkers. These results support that PTP1B could potentially regulate PD via antineuroinflammation and antiapoptotic pathways.

Glioblastoma multiforme (GBM) is a cancer of the central nervous system with limited therapeutic outcomes. Infiltrating cancer cells are the contributing factor to high GBM malignancy. The intracranial brain cancer cell infiltration is a complex cascade involving adhesion, migration, and invasion. An arsenal of natural products has been under exploration to overcome GBM malignancy. This study applied the antimicrobial peptide tilapia piscidin 3 (TP3) to GBM8401, U87MG, and T98G cells. The cellular assays and microscopic observations showed that TP3 significantly attenuated cell adhesion, migration, and invasion. A live‐cell video clip showed the inhibition of filopodia protrusions and cell attachment. Probing at the molecular levels showed that the proteolytic activities (from secretion), the mRNA and protein expression levels of matrix metalloproteinases‐2 and ‐9 were attenuated. This result strongly evidenced that both invasion and metastasis were inhibited, although metastatic GBM is rare. Furthermore, the protein expression levels of cell‐mobilization regulators focal adhesion kinase and paxillin were decreased. Similar effects were observed in small GTPase (RAS), phosphorylated protein kinase B (AKT) and MAP kinases such as extracellular signal‐regulated kinases (ERK), JNK, and p38. Overall, TP3 showed promising activities to prevent cell infiltration and metastasis through modulating the tumor microenvironment balance, suggesting that TP3 merits further development for use in GBM treatments., We first describe the anti‐cancer activities of the antimicrobial peptide tilapia piscidin 3 which inhibits infiltration and motility of glioblastoma multiforme cells.

Glioblastoma multiforme (GBM) is a malignant primary brain tumor. The 5-year relative survival rate of patients with GBM remains &lt, 30% on average despite aggressive treatments, and secondary therapy fails in 90% of patients. In chemotherapeutic failure, detoxification proteins are crucial to the activity of chemotherapy drugs. Usually, glutathione S-transferase (GST) superfamily members act as detoxification enzymes by activating xenobiotic metabolites through conjugation with glutathione in healthy cells. However, some overexpressed GSTs not only increase GST activity but also trigger chemotherapy resistance and tumorigenesis-related signaling transductions. Whether GSTM3 is involved in GBM chemoresistance remains unclear. In the current study, we found that T98G, a GBM cell line with pre-existing temozolomide (TMZ) resistance, has high glycolysis and GSTM3 expression. GSTM3 knockdown in T98G decreased glycolysis ability through lactate dehydrogenase A activity reduction. Moreover, it increased TMZ toxicity and decreased invasion ability. Furthermore, we provide next-generation sequencing–based identification of significantly changed messenger RNAs of T98G cells with GSTM3 knockdown for further research. GSTM3 was downregulated in intrinsic TMZ-resistant T98G with a change in the expression levels of some essential glycolysis-related genes. Thus, GSTM3 was associated with glycolysis in chemotherapeutic resistance in T98G cells. Our findings provide new insight into the GSTM3 mechanism in recurring GBM.

Background Osteoarthritis (OA) is the most common joint disease, especially affecting the knee joint. Etoricoxib, a highly selective cyclooxygenase (COX)-2 inhibitor which can reduce postoperative pain after orthopaedic surgery. The aim of this study was to investigate the effects of oral etoricoxib on the development of OA and to examine concomitant changes in the nociceptive behaviour of rats. Method OA was induced in wistar rats by anterior cruciate ligament transection (ACLT) of the right knee. The ACLT + etoricoxib groups received 6.7 or 33.3 mg/kg of oral etoricoxib three times a week for 12 consecutive weeks, starting at week 8 after ACLT. Nociceptive behaviours and changes in knee joint width during OA development were analyzed. Histopathological studies were then performed on the cartilage. Immunohistochemical analysis was performed to examine the effect of etoricoxib on the expression of transforming growth factor-beta (TGF-β) and nerve growth factor (NGF) in articular cartilage chondrocytes. Results OA rats receiving etoricoxib showed a significantly lower degree of cartilage degeneration than the rats receiving placebo. Nociceptive behaviour studies showed significant improvement in the ACLT + etoricoxib groups compared to that in the ACLT group. Moreover, etoricoxib attenuated NGF expression, but increased TGF-β expression, in OA-affected cartilage. Conclusions Oral etoricoxib in a rat OA model (a) attenuates the development of OA, (b) concomitantly reduces nociception, and (c) modulates chondrocyte metabolism, possibly by inhibiting NGF expression and increasing TGF-β expression. Significance Oral administration of etoricoxib can attenuate the development of OA, with an associated attenuation of nociceptive behaviour in an experimental rat OA model. Moreover, etoricoxib attenuated NGF expression, but enhanced TGF-β expression in OA-affected chondrocytes. These findings may pave the way for further investigations of etoricoxib as a potential therapeutic target for the treatment of the inflammatory component in OA.

SummaryAims We previously demonstrated that intrathecal IL-1β upregulated phosphorylation of p38 mitogen-activated protein kinase (P-p38 MAPK) and inducible nitric oxide synthase (iNOS) in microglia and astrocytes in spinal cord, increased nitric oxide (NO) release into cerebrospinal fluid, and induced thermal hyperalgesia in rats. This study investigated the role of spinal glutamatergic response in intrathecal IL-1β-induced nociception in rats. Methods The pretreatment effects of MK-801 (5 μg), minocycline (20 μg), and SB203580 (5 μg) on intrathecal IL-1β (100 ng) in rats were measured by behavior, Western blotting, CSF analysis, and immunofluorescence studies. Results IL-1β increased phosphorylation of NR-1 (p-NR1) subunit of N-methyl-D-aspartate receptors in neurons and microglia, reduced glutamate transporters (GTs; glutamate/aspartate transporter by 60.9%, glutamate transporter-1 by 55.0%, excitatory amino acid carrier-1 by 39.8%; P

Two new 11,20-epoxybriaranes, fragilides P (1) and Q (2), as well as two known analogues, robustolide F (3) and juncin Z (4), were obtained from the gorgonian coral Junceella fragilis. The structures, including the absolute configurations of briaranes 1 and 2, were elucidated by using spectroscopic methods and comparing the spectroscopic and rotation data with those of known related analogues. Briarane 4 decreased the generation of superoxide anions by human neutrophils. The propionate group in 1 is rarely found.

Pharmaceutical agents for halting the progression of Parkinson&rsquo, s disease (PD) are lacking. The current available medications only relieve clinical symptoms and may cause severe side effects. Therefore, there is an urgent need for novel drug candidates for PD. In this study, we demonstrated the neuroprotective activity of stellettin B (SB), a compound isolated from marine sponges. We showed that SB could significantly protect SH-SY5Y cells against 6-OHDA-induced cellular damage by inhibiting cell apoptosis and oxidative stress through PI3K/Akt, MAPK, caspase cascade modulation and Nrf2/HO-1 cascade modulation, respectively. In addition, an in vivo study showed that SB reversed 6-OHDA-induced a locomotor deficit in a zebrafish model of PD. The potential for developing SB as a candidate drug for PD treatment is discussed.

Parkinson’s disease (PD) is one of the most common age-related neurodegenerative diseases, and neuroinflammation has been identified as one of its key pathological characteristics. Triggering receptors expressed on myeloid cells-1 (TREM-1) amplify the inflammatory response and play a role in sepsis and cancer. Recent studies have demonstrated that the attenuation of TREM-1 activity produces cytoprotective and anti-inflammatory effects in macrophages. However, no study has examined the role of TREM-1 in neurodegeneration. We showed that LP17, a synthetic peptide blocker of TREM-1, significantly inhibited the lipopolysaccharide (LPS)-induced upregulation of proinflammatory cascades of inducible nitric oxide synthase (iNOS), cyclooxygenase-2, and nuclear factor-kappa B. Moreover, LP17 enhanced the LPS-induced upregulation of autophagy-related proteins such as light chain-3 and histone deacetylase-6. We also knocked down TREM-1 expression in a BV2 cell model to further confirm the role of TREM-1. LP17 inhibited 6-hydroxydopamine-induced locomotor deficit and iNOS messenger RNA expression in zebrafish. We also observed therapeutic effects of LP17 administration in 6-hydroxydopamine-induced PD syndrome using a rat model. These data suggest that the attenuation of TREM-1 could ameliorate neuroinflammatory responses in PD and that this neuroprotective effect might occur via the activation of autophagy and anti-inflammatory pathways.

Angiogenesis and invasion are highly related with tumor metastatic potential and recurrence prediction in the most aggressive brain cancer, glioblastoma multiforme (GBM). For the first time, this study reveals that marine-sponge-derived stellettin B reduces angiogenesis and invasion. We discovered that stellettin B reduces migration of glioblastoma cells by scratch wound healing assay and invasion via chamber transwell assay. Further, stellettin B downregulates Akt/Mammalian Target of Rapamycin (Akt/mTOR) and Signal transducer and activator of transcription 3 (Stat3) signaling pathways, which are essential for invasion and angiogenesis in glioblastoma. This study further demonstrates that stellettin B affects filamentous actin (F-actin) rearrangement by decreasing the cross-linkage of phosphor-Girdin (p-Girdin), which attenuates glioblastoma cell invasion. Moreover, stellettin B blocks the expression and secretion of a major proangiogenic factor, vascular endothelial growth factor (VEGF), in glioblastoma cells. Stellettin B also reduces angiogenic tubule formation in human umbilical vein endothelial cells (HUVECs). In vivo, we observed that stellettin B decreased blood vesicle formation in developmental zebrafish and suppressed angiogenesis in Matrigel plug transplant assay in mice. Decreased VEGF transcriptional expression was also found in stellettin B&ndash, treated zebrafish embryos. Overall, we conclude that stellettin B might be a potential antiangiogenic and anti-invasion agent for future development of therapeutic agents for cancer therapy.

Several studies suggest that glial scars pose as physical and chemical barriers that limit neurite regeneration after spinal cord injury (SCI). Evidences suggest that the activation of the PI3K/Akt/mTOR signaling pathway is involved in glial scar formation. Therefore, inhibition of the PI3K/Akt/mTOR pathway may beneficially attenuate glial scar formation after SCI. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) negatively regulates the PI3K/Akt/mTOR pathway. Therefore, we hypothesized that the overexpression of PTEN in the spinal cord will have beneficial effects after SCI. In the present study, we intrathecally injected a recombinant adenovirus carrying the pten gene (Ad-PTEN) to cause overexpression of PTEN in rats with contusion injured spinal cords. The results suggest overexpression of PTEN in spinal cord attenuated glial scar formation and led to improved locomotor function after SCI. Overexpression of PTEN following SCI attenuated gliosis, affected chondroitin sulfate proteoglycan expression, and improved axon regeneration into the lesion site. Furthermore, we suggest that the activation of the PI3K/Akt/mTOR pathway in astrocytes at 3 days after SCI may be involved in glial scar formation. Because delayed treatment with Ad-PTEN enhanced motor function recovery more significantly than immediate treatment with Ad-PTEN after SCI, the results suggest that the best strategy to attenuate glial scar formation could be to introduce 3 days after SCI. This study's findings thus have positive implications for patients who are unable to receive immediate medical attention after SCI.

Platelet-rich plasma (PRP) is prepared by centrifuging fresh blood in an anticoagulant state, and harvesting the platelet-rich portion or condensing platelets. Studies have consistently demonstrated that PRP concentrates are an abundant source of growth factors, such as platelet-derived growth factor (PDGF), transforming growth factor β (TGF-β), insulin-like growth factor 1 (IGF-1), and epithelial growth factor (EGF). The complex mechanisms underlying spinal cord injury (SCI) diminish intrinsic repair and neuronal regeneration. Several studies have suggested that growth factor-promoted axonal regeneration can occur for an extended period after injury. More importantly, the delivery of exogenous growth factors contained in PRP, such as EGF, IGF-1, and TGF-β, has neurotrophic effects on central nervous system (CNS) injuries and neurodegenerative diseases. However, only a few studies have investigated the effects of PRP on CNS injuries or neurodegenerative diseases. According to our review of relevant literature, no study has investigated the effect of intrathecal (i.t.) PRP injection into the injured spinal cord and activation of intrinsic mechanisms. In the present study, we directly injected i.t. PRP into rat spinal cords and examined the effects of PRP on normal and injured spinal cords. In rats with normal spinal cords, PRP induced microglia and astrocyte activation and PDGF-B and ICAM-1 expression. In rats with SCIs, i.t. PRP enhanced the locomotor recovery and spared white matter, promoted angiogenesis and neuronal regeneration, and modulated blood vessel size. Furthermore, a sustained treatment (a bolus of PRP followed by a 1/3 dose of initial PRP concentration) exerted more favorable therapeutic effects than a single dose of PRP. Our findings suggest by i.t. PRP stimulate angiogenesis, enhancing neuronal regeneration after SCI in rats. Although PRP induces minor inflammation in normal and injured spinal cords, it has many advantages. It is an autologous, biocompatible, nontoxic material that does not result in a major immune response. In addition, based on its safety and ease of preparation, we hypothesize that PRP is a promising therapeutic agent for SCI.

Summary Aims To date, no reliable methods have proven effective for treating spinal cord injury (SCI). Even systemic administration of methylprednisolone (MP) remains controversial. We previously reported that intrathecal (i.t.) administration of granulocyte colony-stimulating factor (G-CSF) improves outcome after experimental spinal cord ischemic insults in rats. The present study aimed to examine the neuroprotective efficacy of i.t. G-CSF or MP in rats with SCI. Methods Female rats were subjected to spinal cord contusion injury at T10 using NYU impactor. We i.t. administered G-CSF (10 μg) or MP (one bolus of 100 μg, followed by 18 μg/h infusion for 23 h) immediately after SCI. Results Both G-CSF and MP significantly improved the rats’ motor function after SCI. Immunofluorescence staining revealed suppressed expression of transforming growth factor-beta 1 (TGF-β1), chondroitin sulfate proteoglycans (neurocan and phosphacan), OX-42 and tumor necrosis factor alpha after i.t. G-CSF, but not MP, in rats with SCI. In addition, G-CSF significantly decreased the expression of astrocytic TGF-β1 and glial fibrillary acidic protein around the injury site. Furthermore, rats with G-CSF treatment showed increased neurofilament expression beyond the glial scars. Conclusion Direct i.t. administration of G-CSF provides a promising therapeutic option for SCI or related spinal diseases.

Dihydroaustrasulfone alcohol is the synthetic precursor of austrasulfone, which is a marine natural product, isolated from the Taiwanese soft coral Cladiella australis. Dihydroaustrasulfone alcohol has anti-inflammatory, neuroprotective, antitumor and anti-atherogenic properties. Although dihydroaustrasulfone alcohol has been shown to inhibit neointima formation, its effect on human vascular smooth muscle cells (VSMCs) has not been elucidated. We examined the effects and the mechanisms of action of dihydroaustrasulfone alcohol on proliferation, migration and phenotypic modulation of human aortic smooth muscle cells (HASMCs). Dihydroaustrasulfone alcohol significantly inhibited proliferation, DNA synthesis and migration of HASMCs, without inducing cell death. Dihydroaustrasulfone alcohol also inhibited platelet-derived growth factor (PDGF)-induced expression of cyclin-dependent kinases (CDK) 2, CDK4, cyclin D1 and cyclin E. In addition, dihydroaustrasulfone alcohol inhibited PDGF-induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), whereas it had no effect on the phosphorylation of phosphatidylinositol 3-kinase (PI3K)/(Akt). Moreover, treatment with PD98059, a highly selective ERK inhibitor, blocked PDGF-induced upregulation of cyclin D1 and cyclin E and downregulation of p27kip1. Furthermore, dihydroaustrasulfone alcohol also inhibits VSMC synthetic phenotype formation induced by PDGF. For in vivo studies, dihydroaustrasulfone alcohol decreased smooth muscle cell proliferation in a rat model of restenosis induced by balloon injury. Immunohistochemical staining showed that dihydroaustrasulfone alcohol noticeably decreased the expression of proliferating cell nuclear antigen (PCNA) and altered VSMC phenotype from a synthetic to contractile state. Our findings provide important insights into the mechanisms underlying the vasoprotective actions of dihydroaustrasulfone alcohol and suggest that it may be a useful therapeutic agent for the treatment of vascular occlusive disease.

A known norcembranoidal diterpene, 5-episinuleptolide (1), along with a new analogue, 4α-hydroxy-5-episinuleptolide (2), were isolated from a cultured-type soft coral Sinularia numerosa. The structures of 1 and 2 were elucidated on the basis of spectroscopic methods and by comparison of the data with those of the related metabolites. Cytotoxicity of metabolites 1 and 2 against a panel of tumor cells is also described. Compound 2 exhibited moderate cytotoxicity toward CCRF-CEM cells with an IC50 value 4.21 μg/mL. Preliminary SAR (structure activity relationship) information was obtained from these two compounds.

Parkinson's disease (PD) is a neurodegenerative disease that is characterized by the progressive loss of dopaminergic (DA) neurons in the substantia nigra. However, current treatments for PD are mainly palliative. Recently, researchers discovered that neurotoxins can induce Parkinsonian-like symptoms in zebrafish. No study to date has investigated the characteristics of PD, such as neuroinflammation factors, oxidative stress, or ubiquitin dysfunction, in this model. Therefore, the current study was aimed at utilizing commonly used clinical drugs, minocycline, vitamin E, and Sinemet, to test the usefulness of this model. Previous studies had indicated that DA cell loss was greater with 6-hydroxydopamine (6-OHDA) than with other neurotoxins. Thus, we first challenged zebrafish with 6-OHDA immersion and found a significant reduction in zebrafish locomotor activity; we then reversed the locomotor disruptions by treatment with vitamin E, Sinemet, or minocycline. The present study also analyzed the mRNA expression of parkin, pink1, and cd-11b, because the expression of these molecular targets has been shown to result in attenuation in mammalian models of PD. Vitamin E, Sinemet, and minocycline significantly reversed 6-OHDA-induced changes of parkin, pink1, and cd-11b mRNA expression in zebrafish. Moreover, we assessed tyrosine hydroxylase (TH) expression to confirm the therapeutic effects of vitamin E tested on this PD model and established that vitamin E reversed the 6-OHDA-induced damage on TH expression. Our results provide some support for the validity of this in vivo Parkinson's model, and we hope that this model will be more widely used in the future.

Five new 7α-hydroxyeunicellin-based diterpenoids, designated as cladieunicellins M–Q (1–5), were isolated from a Formosan octocoral Cladiella sp. The structures of 1–5 were elucidated on the basis of spectroscopic methods and by comparison of the data with those of the related metabolites. Cytotoxicity of metabolites 1–5 against the human leukemia Molt 4 and HL 60 is also described. Among them, compounds 1, 3 and 5 exhibited moderate cytotoxicity toward Molt 4 cells with IC50 values 16.43, 14.17 and 15.55 μM, respectively. Preliminary SAR (structure activity relationship) information was obtained from these compounds and their analogues.

Two new eunicellin-based diterpenoids, cladieunicellins K (1) and L (2), were isolated from an octocoral Cladiella sp. The structures of 1 and 2 were elucidated by spectroscopic methods and 2 exhibited moderate cytotoxicity towards the MOLT-4 human leukemia.

A new norcembranoidal diterpene, 1-epi-sinulanorcembranolide A (1), and a new cembranoidal diterpene, flexibilin D (2), were isolated from the soft corals, Sinularia gaweli and Sinularia flexibilis, respectively. The structures of new metabolites 1 and 2 were elucidated by spectroscopic methods, and compound 2 was found to significantly inhibit the accumulation of the pro-inflammatory iNOS and COX-2 proteins of the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. In addition, S. flexibilis yielded a known cembrane, 5-dehydrosinulariolide (3); the structure, including its absolute stereochemistry, was further confirmed by single-crystal X-ray diffraction analysis.

A new sterol, (22R,23R,24R)-5α,8α-epidioxy-22,23-methylene-24-methyl-cholest-6,9(11)-dien-3β-ol (1), and two known sterols, (22R,23R,24R)-5α,8α-epidioxy-22,23-methylene-24-methylcholest-6-en-3β-ol (2) and 24-methylenecholestane-1α,3β,5α, 6β,11α-pentol (3), were isolated from the soft coral Sinularia gaweli. The structure of sterol 1 was established by spectroscopic methods and by comparison of the spectral data with those of known analogues. The cytotoxicity of sterols 1–3 towards various tumor cells is reported.

During cortical development, cell proliferation and cell cycle exit are carefully regulated to ensure that the appropriate numbers of cells are produced. Urocortin (UCN) is a member of the corticotrophin releasing hormone (CRH) family of neuropeptides that regulates stress responses. UCN is widely distributed in adult rat brain. However, the expression and function of UCN in embryonic brain is, as yet, unclear. Here, we show that UCN is endogenously expressed in proliferative zones of the developing cerebral cortex and its receptors are exhibited in neural stem cells (NSCs), thus implicating the neuropeptide in cell cycle regulation. Treatment of cultured NSCs or organotypic slice cultures with UCN markedly reduced cell proliferation. Furthermore, blocking of endogenous UCN/CRHRs system either by treatment with CRHRs antagonists or by neutralization of secreted UCN with anti-UCN antibody increased NSCs proliferation. Cell cycle kinetics analysis demonstrated that UCN lengthened the total cell cycle duration via increasing the G1 phase and accelerated cell cycle exit. UCN directly inhibited the histone deacetylase (HDAC) activity and induced a robust increase in histone H3 acetylation levels. Using pharmacological and RNA interference approaches, we further demonstrated that antiproliferative action of UCN appeared to be mediated through a HDAC inhibition-induced p21 upregulation. Moreover, UCN treatment in vitro and in vivo led to an increase in neuronal differentiation of NSCs. These findings suggest that UCN might contribute to regulate NSCs proliferation and differentiation during cortical neurogenesis.

Urocortin (UCN) is a member of the corticotropin-releasing hormone (CRH) family of neuropeptides that regulates stress responses. Although UCN is principally expressed in dopaminergic neurons in rat substantia nigra (SN), the function of UCN in modulating dopaminergic neuronal survival remains unclear. Using primary mesencephalic cultures, we demonstrated that dopaminergic neurons underwent spontaneous cell death when their age increased in culture. Treatment of mesencephalic cultures with UCN markedly prolonged the survival of dopaminergic neurons, whereas neutralization of UCN with anti-UCN antibody accelerated dopaminergic neurons degeneration. UCN increased intracellular cAMP levels followed by phosphorylating glycogen synthase kinase-3β (GSK-3β) on Ser9. Moreover, UCN directly inhibited the histone deacetylase (HDAC) activity and induced a robust increase in histone H3 acetylation levels. Using pharmacological approaches, we further demonstrated that inhibition of GSK-3β and HDAC contributes to UCN-mediated neuroprotection. These results suggest that dopaminergic neurons-derived UCN might be involved in an autocrine protective signaling mechanism.

Recently, it has been suggested that anesthetic agents may have neuroprotective potency. The notion that anesthetic agents can offer neuroprotection remains controversial. Propofol, which is a short-acting intravenous anesthetic agent, may have potential as a neuroprotective agent. In this study, we tried to determine whether propofol affected the viability of human neuroblastoma SH-SY5Y cells by using the MTT assay. Surprisingly, our results showed that propofol at a dose of 1–10 μM could improve cell proliferation. However, at higher doses (200 μM), propofol appears to be cytotoxic. On the other hand, propofol could up-regulate the expression of key proteins involved in neuroprotection including B-cell lymphoma 2 at a dose range of 1–10 μM, activation of phospho-serine/threonine protein kinase at a dose range of 0.5–10 μM, and activation of phospho-extracellular signal-regulated kinases at a dose range of 5–10 μM. Similarly, we demonstrate that propofol (10 μM) could elevate protein levels of heat shock protein 90 and heat shock protein 70. Therefore, we choose to utilize a 10 μM concentration of propofol to assess neuroprotective activities in our studies. In the following experiments, we used dynorphin A to generate cytotoxic effects on SH-SY5Y cells. Our data indicate that propofol (10 μM) could inhibit the cytotoxicity in SH-SY5Y cells induced by dynorphin A. Furthermore, propofol (10 μM) could decrease the expression of the p-P38 protein as well. These data together suggest that propofol may have the potential to act as a neuroprotective agent against various neurologic diseases. However, further delineation of the precise neuroprotective effects of propofol will need to be examined.

A new natural marine nor-sesquiterpenoid, (+)-pathylactone A (1), along with a know nor-sesquiterpenoid, napalilactoe (2), were isolated from the octocoral Paralemnalia thyrsoides. The structure of 1 was established on the basis of spectroscopic methods and by comparison of the spectral data with those of synthetic analogues. Nor-sesquiterpenoid 1 was found to inhibit the protein experssion of pro-inflammatory inducible nitric oxide synthase (iNOS) in a murine macrophage-like cell line.

Background and purpose: Natural compounds obtained from marine organisms have received considerable attention as potential sources of novel drugs for treatment of human inflammatory diseases. Capnellene, isolated from the marine soft coral Capnella imbricate, 4,4,6a-trimethyl-3-methylene-decahydro-cyclopenta[]pentalene-2,3a-diol (GB9) exhibited anti-inflammatory actions on activated macrophages in vitro. Here we have assessed the anti-neuroinflammatory properties of GB9 and its acetylated derivative, acetic acid 3a-hydroxy-4,4,6a-trimethyl-3-methylene-decahydro-cyclopenta[]pentalen-2-yl ester (GB10). Experimental approach: Effects of GB9 or GB10 on the expression of inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) in interferon-γ (IFN-γ)-stimulated mouse microglial BV2 cells were measured by Western blot. The in vivo effects of these compounds were examined in the chronic constriction injury (CCI) rat model of neuropathic pain, measuring thermal hyperalgesia, and microglial activation and COX-2 protein in lumbar spinal cord, by immunohistochemistry. Key results: In BV2 cells, GB9 and GB10 inhibited the expression of iNOS and COX-2, stimulated by IFN-γ. Intrathecal administration of GB9 and GB10 inhibited CCI-induced nociceptive sensitization and thermal hyperalgesia in a dose-dependent manner. Intraperitoneal injection of GB9 inhibited CCI-induced thermal hyperalgesia and also inhibited CCI-induced activation of microglial cells and up-regulation of COX-2 in the dorsal horn of the lumbar spinal cord ipsilateral to the injury. Conclusion and implications: Taken together, these data indicate that the marine-derived capnellenes, GB9 and GB10, had anti-neuroinflammatory and anti-nociceptive properties in IFN-γ-stimulated microglial cells and in neuropathic rats respectively. Therefore, capnellene may serve as a useful lead compound in the search for new therapeutic agents for treatment of neuroinflammatory diseases.

Recent evidence has demonstrated that hyaluronan synthase 2 mRNA is up-regulated after brain ischemia. After a cerebral ischemic event, microglia and macrophages are the major inflammatory cells and are activated by hyaluronan (HA). However, it is unclear how these cells compare with regard to HA responsiveness. We show here that peritoneal macrophages and RAW 264.7 macrophages produced more than five- and 10-fold more tumor necrosis factor-alpha (TNF-alpha) than primary microglia and BV-2 microglia, respectively. Antibody blockade study showed that CD44, Toll-like receptor-4 receptor and the receptor for HA-mediated motility were responsible for HA-induced TNF-alpha release. Furthermore, HA induced higher levels of phosphorylated MAPK in RAW 264.7 cells when compared with BV-2 cells. HA-mediated TNF-alpha production required p38 MAPK, extracellular-regulated kinase and c-Jun N-terminal kinase phosphorylation in both cell types. The levels of HA-induced TNF-alpha mRNA expression in BV-2 cells were only twofold lower compared with RAW 264.7 cells, suggesting that a translational event is involved in the differential production of TNF-alpha. Western blot analysis revealed that HA treatment resulted in more rapid phosphorylation of eukaryotic initiation factor 4E-binding protein 1 (4E-BP1) and more effective dissociation of 4E-BP1 from eukaryotic initiation factor 4E in RAW 264.7 cells than in BV-2 cells. Additionally, HA-induced phosphorylation of 4E-BP1 was dependent on MAPK signaling, indicating that RAW 264.7 cells exhibited higher levels of hyperphosphorylated 4E-BP1 possibly due to the overactivation of MAPK. The results suggest that resident microglia and blood-derived monocytes/macrophages exhibit differential sensitivities in response to extracellular mediators after brain ischemia.

Summary: Purpose: Perinatal hypoxia is an important cause of brain injury in the newborn and has consequences that are potentially devastating and life-long, such as an increased risk of epilepsy in later life. The postsynaptic density (PSD) is a cytoskeletal specialization involved in the anchoring of neurotransmitter receptors and in regulating the response of postsynaptic neurons to synaptic stimulation. The postsynaptic protein PSD-95 binds to the N-methyl-d-aspartate receptor (NMDAR) subunit, and hence activates cascades of NMDAR-mediated events, such as cyclic adenosine monophosphate (cAMP)-responsive element binding protein phosphorylation at serine-133 (pCREBSerine-133). Here we studied the effect of perinatal hypoxia on protein interactions involving PSD-95 and the NMDAR, as well as pCREBSer-133 expression at an age when the animals show increased seizure susceptibility. Methods: Rats were assigned randomly to the control rats or the rats exposed to transient global hypoxia at postnatal day 10 (P10). At P45, some rats from both groups were treated with pentylenetetrazol (PTZ) intraperitoneally to test the seizure threshold, and others were studied for neuronal loss, pCREBSerine-133, PSD-95, and NMDAR expressions in the midbrain, temporal cortex, and hippocampal CA1 subfield by using immunohistochemistry, co-immunoprecipitation, and immunoblotting techniques, respectively. Results: The rats with prior exposure to perinatal hypoxia exhibited increased seizure susceptibility to PTZ, compared with the control rats. Associated with this long-term change in seizure susceptibility, selective neuronal loss was observed in the midbrain region while pCREBSer-133 expression was reduced in the midbrain, temporal cortex, and hippocampal CA1 subfield. Perinatal hypoxia led to a decrease in PSD-95 expression in the both midbrain and hippocampal CA1 subfield, with the exception of temporal cortex. Furthermore, the association between PSD-95 and NMDAR subunits (NR1, NR2A, and NR2B) in the hippocampal CA1 was also markedly altered by perinatal hypoxia. Conclusions: This study demonstrates that the decrease in several protein complexes that are essential components of the postsynaptic apparatus is associated with the observed increase in seizure susceptibility in adult rats with prior exposure to perinatal hypoxia. The results indicate that reductions in PSD-95 expression, PSD-95 binding of NMDAR subunits, and subsequent NMDAR-mediated CREB phosphorylation, particularly in hippocampal CA1, are long-term consequences of perinatal hypoxia and may, at least in part, contribute to perinatal hypoxia-induced reduction in seizure threshold.

Objective To observe the feasibility of using fibrin gel as a scaffold during rabbit spinal fusion with rat kidney cells carrying bone morphogenetic protein-2 (BMP-2) expression vector. Methods Normal Rattusnorvegicus (rat) kidney (NRK) cells were transfected with pCMV-BMP2 vectors by using a nonviral reagent (FuGENE6), following which the transfected cells (1.5 x 10(7)) were encapsulated and evenly suspended in a fibrin scaffold, and implanted to either side of the L5-L6 intertransverse space for six test rabbits. For the control group (six rabbits), the transfected cells (1.5 x 10(7)) were added on and absorbed in a surgical gelatin sponge, and implanted in an analogous location. Radiographs of the spine of all animals were taken at six, ten, and 12 weeks subsequent to fusion surgery. Gross and histological examination of the fusion masses for all the animals were performed subsequent to animals having been sacrificed at 12 weeks. Results Expression of BMP-2 was verified in the pCMV-BMP2 transfected NRK cells which were used for the subsequent rabbit experiment. For all 12 rabbits, no evidence of implanted-tissue rejection was seen during the postoperative course. Neither residual scaffold nor inflammatory granulation tissue was seen in the harvested spinal segments. For the six study-group rabbits, radiographic examinations revealed that four individuals (67%) featured prominent new-bone formation (good fusion), and two (33%) revealed moderate new-bone formation (fair fusion) at the implanted sites, whereas all six control-group rabbits revealed no evidence of new-bone formation (nonfusion) at the implanted sites. For the histological examinations, all animals in the study group revealed the presence of osseous tissue at the sites corresponding to the sites of radiographically demonstrated new-bone formation, whereas for the control group, no osseous tissue was seen at the implanted sites for any animal Conclusion Fibrin gel, being a biocompatible and biodegradable matrix, can encapsulate pCMV-BMP2 transfected NRK cells and adhere to the intertransverse lumbar-spine spaces of test rabbits. With the above characteristics, it plays an important role in the successful delivery of pCMV-BMP2-transfected cells for this rabbit spinal-fusion experiment. Being a natural matrix and able to be obtained readily from patients' own blood, fibrin gel seems to be a promising scaffold for future gene therapy in human trials.

A novel ubichromenol derivative, pseudoalteromone C (1), possessing a 9C nor-monoterpenoid moiety was produced from CGH2XX, a Pseudoaltermonas sp. strain that was originally cloned from bacteria communities associated with the cultured-type octocoral Lobophytum crassum. The structure of 1 was elucidated by using spectroscopic methods and comparing the spectroscopic data with those of known related metabolites.

Previous studies have demonstrated that the marine compound austrasulfone, isolated from the soft coral Cladiella australis, exerts a neuroprotective effect. The intermediate product in the synthesis of austrasulfone, dihydroaustrasulfone alcohol, attenuates several inflammatory responses. The present study uses in vitro and in vivo methods to investigate the neuroprotective effect of dihydroaustrasulfone alcohol-modified 1-tosylpentan-3-one (1T3O). Results from in vitro experiments show that 1T3O effectively inhibits 6-hydroxydopamine-induced (6-OHDA-induced) activation of both p38 mitogen-activated protein kinase (MAPK) and caspase-3 in SH-SY5Y cells; and enhances nuclear factor erythroid 2–related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression via phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling. Hoechst staining and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining results reveal that 1T3O significantly inhibits 6-OHDA-induced apoptosis. In addition, the addition of an Akt or HO-1 inhibitor decreases the protective effect of 1T3O. Thus, we hypothesize that the anti-apoptotic activity of 1T3O in neuronal cells is mediated through the regulation of the Akt and HO-1 signaling pathways. In vivo experiments show that 1T3O can reverse 6-OHDA-induced reduction in locomotor behavior ability in zebrafish larvae, and inhibit 6-OHDA-induced tumor necrosis factor-alpha (TNF-α) increase at the same time. According to our in vitro and in vivo results, we consider that 1T3O exerts its anti-apoptotic activities at SH-SY5Y cells after 6-OHDA challenges, probably via the regulation of anti-oxidative signaling pathways. Therefore, this compound may be a promising therapeutic agent for neurodegenerations.

To date, no study has been conducted to explore the bioactivity of the crinoid Comanthus bennetti. Here we report the anti-inflammatory properties of comaparvin (5,8-dihydroxy-10-methoxy-2-propylbenzo[h]chromen-4-one) based on in vivo experiments. Our preliminary screening for anti-inflammatory activity revealed that the crude extract of Comanthus bennetti significantly inhibited the expression of pro-inflammatory proteins in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophage cells. Comaparvin isolated from crinoids significantly decreased the expression of inducible nitric oxide synthase (iNOS) protein and mRNA in LPS-stimulated macrophage cells. Moreover, our results showed that post-treatment with comaparvin significantly inhibited mechanical allodynia, thermal hyperalgesia and weight-bearing deficits in rats with carrageenan-induced inflammation. Comaparvin also attenuated leukocyte infiltration and iNOS protein expression in carrageenan-induced inflamed paws. These results suggest that comaparvin is a potential anti-inflammatory therapeutic agent against inflammatory pain.

A suitable small animal model may help in the screening and evaluation of new drugs, especially those from natural products, which can be administered at lower dosages, fulfilling an urgent worldwide need. In this study, we explore whether zebrafish could be a model organism for carrageenan-induced abdominal edema. The research results showed that intraperitoneal (i.p.) administration of 1.5% λ-carrageenan in a volume of 20 µL significantly increased abdominal edema in adult zebrafish. Levels of the proinflammatory proteins tumor necrosis factor-α (TNF-α) and inducible nitric oxide synthase (iNOS) were increased in carrageenan-injected adult zebrafish during the development of abdominal edema. An associated enhancement was also observed in the leukocyte marker, myeloperoxidase (MPO). To support these results, we further observed that i.p. methylprednisolone (MP; 1 µg), a positive control, significantly inhibited carrageenan-induced inflammation 24 h after carrageenan administration. Furthermore, i.p. pretreatment with either an anti-TNF-α antibody (1∶5 dilution in a volume of 20 µL) or the iNOS-selective inhibitor aminoguanidine (AG; 1 µg) inhibited carrageenan-induced abdominal edema in adult zebrafish. This new animal model is uncomplicated, easy to develop, and involves a straightforward inducement of inflammatory edema for the evaluation of small volumes of drugs or test compounds.

A natural caulerpenyne-derived sesquiterpene, oxytoxin-2 (1), was isolated from a cultured mollusc Volvatella vigourouxi. The structure of 1 was elucidated on the basis of spectroscopic analysis and this compound was suggested to be a diet-derived metabolite from the green alga Caulerpa sertularioides. This is the first study on the chemical constituents of V. vigourouxi. Oxytoxin-2 (1) was found to inhibit significantly the expression of the pro-inflammatory inducible nitric oxide synthase (iNOS) protein of lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells.

Previous studies have reported that the intrathecal (i.t.) administration of transforming growth factor β1 (TGF-β1) prevents and reverses neuropathic pain. However, only limited information is available regarding the possible role and effects of spinal TGF-β1 in neuropathic pain. We aimed to investigate the antinociceptive effects of exogenous TGF-β1 on chronic constriction injury (CCI)-induced neuropathic pain in rats. We demonstrated that sciatic nerve injury caused a downregulation of endogenous TGF-β1 levels on the ipsilateral side of the lumbar spinal dorsal gray matter, and that the i.t. administration of TGF-β1 (.01–10 ng) significantly attenuated CCI-induced thermal hyperalgesia in neuropathic rats. TGF-β1 significantly inhibited CCI-induced spinal neuroinflammation, microglial and astrocytic activation, and upregulation of tumor necrosis factor-α. Moreover, i.t. TGF-β1 significantly attenuated the CCI-induced downregulation of glutamate transporter 1, the glutamate aspartate transporter, and the excitatory amino acid carrier 1 on the ipsilateral side. Furthermore, i.t. TGF-β1 significantly decreased the concentrations of 2 excitatory amino acids, aspartate and glutamate, in the spinal dialysates in CCI rats. In summary, we conclude that the mechanisms of the antinociceptive effects of i.t. TGF-β1 in neuropathy may include attenuation of spinal neuroinflammation, attenuation, or upregulation of glutamate transporter downregulation, and a decrease of spinal extracellular excitatory amino acids. Perspective Clinically, medical treatment is usually initiated after the onset of intractable pain. Therefore, in the present study, i.t. TGF-β1 was designed to be administered 2 weeks after the establishment of CCI pain. Compared to the continuous TGF-β1 infusion mode, single-dose administration seems more convenient and practical to use.

In recent years, a significant number of metabolites with potent anti-inflammatory properties have been discovered from marine organisms, and several of these compounds are now under clinical trials. In the present study, we isolated 11-epi-sinulariolide acetate (Ya-s11), a cembrane-type compound with anti-inflammatory effects, from the Formosa soft coral Sinularia querciformis. Preliminary screening revealed that Ya-s11 significantly inhibited the expression of the proinflammatory proteins induced nitric oxide synthase and cyclooxygenase-2 in lipopolysaccharide-stimulated murine macrophages. We also examined the therapeutic effects of Ya-s11 on adjuvant-induced arthritis (AIA) in female Lewis rats, which demonstrate features similar to human rheumatoid arthritis (RA). Animal experiments revealed that Ya-s11 (subcutaneously 9 mg/kg once every 2 days from day 7 to day 28 postimmunization) significantly inhibited AIA characteristics. Moreover, Ya-s11 also attenuated protein expression of cathepsin K, matrix metalloproteinases-9 (MMP-9), tartrate-resistant acid phosphatase (TRAP), and tumor necrosis factor-α (TNF-α) in ankle tissues of AIA-rats. Based on its attenuation of the expression of proinflammatory proteins and disease progression in AIA rats, the marine-derived compound Ya-s11 may serve as a useful therapeutic agent for the treatment of RA.

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by tremor, rigidity, bradykinesia, and gait impairment. In a previous study, we found that the marine-derived compound 11-dehydrosinulariolide (11-de) upregulates the Akt/PI3K pathway to protect cells against 6-hydroxydopamine (6-OHDA)-mediated damage. In the present study, SH-SY5Y, zebrafish and rats were used to examine the therapeutic effect of 11-de. The results revealed the mechanism by which 11-de exerts its therapeutic effect: the compound increases cytosolic or mitochondrial DJ-1 expression, and then activates the downstream Akt/PI3K, p-CREB, and Nrf2/HO-1 pathways. Additionally, we found that 11-de could reverse the 6-OHDA-induced downregulation of total swimming distance in a zebrafish model of PD. Using a rat model of PD, we showed that a 6-OHDA-induced increase in the number of turns, and increased time spent by rats on the beam, could be reversed by 11-de treatment. Lastly, we showed that 6-OHDA-induced attenuation in tyrosine hydroxylase (TH), a dopaminergic neuronal marker, in zebrafish and rat models of PD could also be reversed by treatment with 11-de. Moreover, the patterns of DJ-1 expression observed in this study in the zebrafish and rat models of PD corroborated the trend noted in previous in vitro studies.

The structures of pubinernoid A (1) and apo-9′-fucoxanthinone (2), isolated from a gorgonian coral Pinnigorgia sp., were elucidated on the basis of spectroscopic analysis and by comparison of their spectroscopic data with those of known compounds. This is the first report of 1 and 2 from an animal source. Apo-9′-fucoxanthinone (2) displayed a significant inhibitory effect on the release of elastase by human neutrophils, with an IC50 value of 5.75 μM.

Three decades ago, the marine-derived compound sinularin was shown to have anti-edematous effects on paw edema induced by carrageenan or adjuvant. To the best of our knowledge, no new studies were conducted to explore the bioactivity of sinularin until we reported the analgesic properties of sinularin based on in vivo experiments. In the present study, we found that sinularin significantly inhibits the upregulation of proinflammatory proteins, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) and upregulates the production of transforming growth factor-β (TGF-β) in lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells according to western blot analysis. We found that subcutaneous (s.c.) administration of sinularin (80 mg/kg) 1 h before carrageenan injection significantly inhibited carrageenan-induced nociceptive behaviors, including thermal hyperalgesia, mechanical allodynia, cold allodynia, and hindpaw weight-bearing deficits. Further, s.c. sinularin (80 mg/kg) significantly inhibited carrageenan-induced microglial and astrocyte activation as well as upregulation of iNOS in the dorsal horn of the lumbar spinal cord. Moreover, s.c. sinularin (80 mg/kg) inhibited carrageenan-induced tissue inflammatory responses, redness and edema of the paw, and leukocyte infiltration. The results of immunohistochemical studies indicate that s.c. sinularin (80 mg/kg) could upregulate production of TGF-β1 in carrageenan-induced inflamed paw tissue. The present results demonstrate that systemic sinularin exerts analgesic effects at the behavioral and spinal levels, which are associated with both inhibition of leukocyte infiltration and upregulation of TGF-β1.Three decades ago, the marine-derived compound sinularin was shown to have anti-edematous effects on paw edema induced by carrageenan or adjuvant. To the best of our knowledge, no new studies were conducted to explore the bioactivity of sinularin until we reported the analgesic properties of sinularin based on in vivo experiments. In the present study, we found that sinularin significantly inhibits the upregulation of proinflammatory proteins, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) and upregulates the production of transforming growth factor-β (TGF-β) in lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells according to western blot analysis. We found that subcutaneous (s.c.) administration of sinularin (80 mg/kg) 1 h before carrageenan injection significantly inhibited carrageenan-induced nociceptive behaviors, including thermal hyperalgesia, mechanical allodynia, cold allodynia, and hindpaw weight-bearing deficits. Further, s.c. sinularin (80 mg/kg) significantly inhibited carrageenan-induced microglial and astrocyte activation as well as upregulation of iNOS in the dorsal horn of the lumbar spinal cord. Moreover, s.c. sinularin (80 mg/kg) inhibited carrageenan-induced tissue inflammatory responses, redness and edema of the paw, and leukocyte infiltration. The results of immunohistochemical studies indicate that s.c. sinularin (80 mg/kg) could upregulate production of TGF-β1 in carrageenan-induced inflamed paw tissue. The present results demonstrate that systemic sinularin exerts analgesic effects at the behavioral and spinal levels, which are associated with both inhibition of leukocyte infiltration and upregulation of TGF-β1.

Parkinson’s disease (PD) is a neurodegenerative disease characterized by tremor, rigidity, bradykinesia, and gait impairment. So far, very few pharmacological agents have been isolated or developed that effectively inhibit the progression of PD. However, several studies have demonstrated that inflammatory processes play critical roles in PD. Therefore, anti-inflammatory agents may suppress disease progression in PD. 11-Dehydrosinulariolide was isolated from cultured soft corals. The anti-inflammatory effect of this molecule has been observed through suppression of the expression of two main pro-inflammatory proteins: inducible nitric oxide synthase and cyclooxygenase-2, in lipopolysaccharide-stimulated macrophage cells. We also found that 11-dehydrosinulariolide significantly reduced 6-hydroxydopamine (6-OHDA)-induced cytotoxicity and apoptosis in a human neuroblastoma cell line (SH-SY5Y). The pharmacological activity of this compound has been studied, and it is associated with the inhibition of 6-OHDA-induced activation of caspase-3 and translocation of nuclear factor kappa B. 11-Dehydrosinulariolide increased the activation of survival-signaling phospho-Akt but not phospho-ERK. The neuroprotective effect of 11-dehydrosinulariolide was assessed here using 6-OHDA-treated SH-SY5Y cells, wherein neuroprotection is mediated through regulation of phosphatidylinositol 3-kinase (PI3K). Furthermore, 11-dehydrosinulariolide caused a significant decrease in caspase-3/7 activity in comparison to the 6-OHDA-treated group, indicating that 11-dehydrosinulariolide has neuroprotective properties. We conclude that 11-dehydrosinulariolide is a promising candidate for the treatment of Parkinson’s disease through its anti-apoptotic and anti-inflammatory action via PI3K signaling.

Microglia are the major inflammatory cells in the brain. Recent studies have highlighted the reciprocal roles of other brain cells in modulating the microglial inflammatory responses. Urocortin (UCN) is a member of the corticotropin-releasing hormone (CRH) family of neuropeptides that function to regulate stress responses. In the present study, we demonstrated that expression of UCN in rat substantia nigra was found to be localized principally to dopaminergic neurons. In cell culture models, the CRH receptors were expressed in microglia, and CRHR expression was up-regulated by treatment with LPS. Thus, it might be proposed that UCN regulates cellular communication between dopaminergic neurons and microglia. We show that femtomolar concentrations of UCN could inhibit LPS-induced TNF-α production in cultured microglia. Investigation of the underlying signaling pathway that mediated the anti-inflammatory effect of UCN the involved PI3K/Akt and glycogen synthase kinase-3β pathway, but not cAMP pathway. Furthermore, UCN protected dopaminergic neurons against LPS-induced neurotoxicity by inhibiting microglial activation in LPS-treated mesencephalic neuron-glia cultures. These results suggest that endogenous UCN and its receptors might be involved in a complex network of paracrine interaction between dopaminergic neurons and glia.

Lemnalol (8-isopropyl-5-methyl-4-methylene-decahydro-1,5-cyclo-naphthalen-3-ol) is a natural compound isolated from the marine soft coral Lemnalia cervicorni. In the present study, the anti-inflammatory and anti-nociceptive properties of lemnalol were investigated in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and carrageenan-injected rats, respectively. Our results demonstrate that lemnalol significantly inhibited the expression of the pro-inflammatory proteins, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), in LPS-stimulated RAW 264.7 cells. An in vivo inflammation model was induced by intraplantar injection of carrageenan into rat hind paws. An intramuscular injection of lemnalol (15 mg/kg) 10 min before carrageenan injection resulted in significant inhibition of carrageenan-induced rat paw edema and thermal hyperalgesia behavior. Western blot experiments revealed that the carrageenan-induced expression of iNOS and COX-2 in paw tissue was significantly down-regulated by lemnalol. Moreover, post-intrathecal injection of lemnalol produced a dose-dependent anti-nociceptive effect in carrageenan-injected rats (1 and 5 microg). The present results indicate that the marine-derived compound lemnalol had anti-inflammatory and analgesic effects in LPS-stimulated RAW 264.7 cells and carrageenan-injected rats, respectively. In addition, inhibition of elevated iNOS and COX-2 protein expression as well as neurophil infiltration of carrageenan-injected paws may be involved in the beneficial effects of lemnalol.

Perinatal hypoxia is an important cause of brain injury amongst the newborn, such injury often resulting in an increased risk of impaired performance as regards learning and memory in later life for the affected individual. The postsynaptic density 95 (PSD-95) protein is a cytoskeletal specialization involved in the anchoring of N-methyl- d -aspartate (NMDA) receptors in postsynaptic neurons and has been reported to serve several important functions (e.g., synaptogenesis, synaptic plasticity and learning and memory performance) for the mammalian brain. Herein we investigated the long-term effects of perinatal hypoxia upon the complex of PSD-95 with NMDAR subunits by means of downstream signalling cAMP response element binding protein (CREB) phosphorylation at the Serine-133 locus (CREBSer-133 phosphorylation) within the hippocampal CA1 area (an essential integration area for mammalian learning and memory) within test-rat brains, as well as the effects upon afflicted-individual long-term learning and memory performance. We also assessed the therapeutic efficacy of dopamine D1/D5 receptor (D1/D5R) activation for such study animals. Perinatal hypoxia on postnatal day ten (P10) led to impaired performance as regards long-term spatial learning and memory (as determined on P45) associated with decreases in the level of CREBSer-133 phosphorylation and decreases in the expression of the complex of PSD-95 with NMDAR subunits (NR1, NR2A, and NR2B). In addition, activation of the D1/D5R via A68930 (a selective, CNS-permeable agonist of D1/D5Rs) administration (2 mg/kg/day, P17–23 inclusively) markedly attenuated the hypoxia-induced deleterious effects, suggesting an effective therapeutic efficacy for A68930. Our results demonstrate the long-term effects of perinatal hypoxia upon the developing brain and provide additional insights into the relative vulnerability of postsynaptic density (PSD) proteins to such insult, as well as the impairment of downstream transcription signalling CREBSer-133 phosphorylation following perinatal hypoxia. More importantly, D1/D5R activation following perinatal hypoxia may be an alternative therapeutic strategy to that which is currently available and may offer significant clinical potential for hypoxia sufferers.

Granulocyte colony-stimulating factor (G-CSF) is known to have various functions such as induction of survival, proliferation and differentiation of hematopoietic cells. Recently, this factor has also been shown to exhibit neuroprotective effects in rat ischemic brain. In the present study, we first demonstrated that both G-CSF and G-CSF receptor were expressed in dopaminergic neurons in the adult substantia nigra and mesencephalic cultures, suggesting that G-CSF might exert its neuroprotective effects in dopaminergic neurons. Pretreatment with G-CSF protected dopaminergic neurons from 6-hydroxydopamine (6-OHDA)-induced neurotoxicity. Investigation of the underlying mechanisms showed that the extracellular-regulated kinase (ERK), but not Janus kinase/signal transducer(s) and activator(s) of transcription (JAK/STAT), was activated following G-CSF treatment. Moreover, G-CSF also increased phosphorylation of Bad, and restored 6-OHDA-induced decrease in Bcl-xL level. The 6-OHDA-caused caspase-3 activation in dopaminergic neurons was inhibited by G-CSF. Inhibition of ERK abrogated G-CSF-mediated Bad phosphorylation, Bcl-xL expression, activated caspase-3 reduction, and the protection of dopaminergic neurons. Taken together, G-CSF prevents dopaminergic neurons from 6-OHDA-induced toxicity via ERK pathway followed by inhibiting the apoptosis-execution process. These results suggest that G-CSF might have a therapeutic potential in Parkinson's disease.

The central nervous system (CNS) exhibits remarkable plasticity in early life and can be altered significantly by various prenatal influences. We previously showed that prenatal exposure to morphine altered kinetic properties of N-methyl-D-aspartate (NMDA) receptor-mediated synaptic currents in the hippocampus of young rat offspring at the age of 14 days (P14). The present study further investigates whether NMDA receptor-mediated synaptic plasticity and/or cyclic adenosine monophosphate-responsive element-binding protein (CREBSerine-133), an important transcription factor underlying learning and memory, can be altered by prenatal morphine exposure in these offspring. Subsequently, the Morris water maze task was performed at the older ages (P28-P31). The magnitude of long-term depression (LTD) generated by a low-frequency stimulation (LFS, 1 Hz for 15 min) in hippocampal slices from the vehicle-control offspring (P14) was significantly larger than that in slices from the morphine-treated offspring, although there was no such difference in the magnitude of long-term potentiation (LTP) elicited by a high-frequency stimulation (100 Hz for 1 s) between the two groups. Comparison of the expression range of glutamatergic synaptic plasticity in slices from the vehicle-control and morphine-treated offspring, calculated as the difference in the maximal magnitude between LTP and LTD, demonstrated a remarkably smaller range in the slices from the morphine-treated offspring. In addition, the decreased phosphorylation of CREBSerine-133 and the impaired ability of spatial learning were also seen in the morphine-treated offspring, as compared with the vehicle-control offspring. Collectively, the study suggests that maternal exposure to morphine reduces the range of synaptic plasticity by decreasing the expression of LTD, but not of LTP, in CA1 pyramidal neurons of the hippocampus from rat offspring. More importantly, decreased phosphorylation of CREBSerine-133 may play a role for the impaired spatial learning and memory in rat offspring exposure to prenatal morphine. Thus, the findings here may provide important insights into cellular/molecular mechanisms underlying pathophysiological changes in the CNS of young offspring from morphine-addicted mothers and serve as a basis for possible therapeutic intervention.

Lower molecular weight of hyaluronan (HA) fragments are capable of activating macrophages to express a number of inflammatory mediators through the interaction with the HA receptor CD44. Recent evidence has demonstrated that concomitant induction of CD44 and HA synthase 2 (HAS-2) mRNA in microglia of the ischemic brain. However, the influence of HA fragments on the activation of microglia is poorly understood. In this study, we demonstrated that HA fragments induced inducible NO synthase (iNOS) expression in BV-2 microglia in a dose-dependent manner and was synergized with interferon-gamma (IFN-gamma). Moreover, HA fragments could induce the activation of p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK1/ERK2), and c-Jun N-terminal kinase (JNK) in a time and dose-dependent fashion. The HA fragments-induced iNOS expression was suppressed by the selective inhibitors of JNK and, to a lesser extent, p38 MAPK. These results suggest that the induction of iNOS by HA fragments is significantly dependent on JNK than on p38 MAPK signaling pathways and support the hypothesis that HA fragments may be an important regulator in the activation of microglia at sites of ischemic brain.

Background Deciphering the mechanisms that modulate the inflammatory response induced by microglial activation not only improves our insight into neuroinflammation but also provides avenues for designing novel therapies that could halt inflammation-induced neuronal degeneration. Decreasing glycogen synthase kinase-3β (GSK-3β) activity has therapeutic benefits in inflammatory diseases. However, the exact molecular mechanisms underlying GSK-3β inactivation-mediated suppression of the inflammatory response induced by microglial activation have not been completely clarified. Tumor necrosis factor-α (TNF-α) plays a central role in injury caused by neuroinflammation. We investigated the regulatory effect of GSK-3β on TNF-α production by microglia to discern the molecular mechanisms of this modulation. Methods Lipopolysaccharide (LPS) was used to induce an inflammatory response in cultured primary microglia or murine BV-2 microglial cells. Release of TNF-α was measured by ELISA. Signaling molecules were analyzed by western blotting, and activation of NF-κB and AP-1 was measured by ELISA-based DNA binding analysis and luciferase reporter assay. Protein interaction was examined by coimmunoprecipitation. Results Inhibition of GSK-3β by selective GSK-3β inhibitors or by RNA interference attenuated LPS-induced TNF-α production in cultured microglia. Exploration of the mechanisms by which GSK-3β positively regulates inflammatory response showed that LPS-induced IκB-α degradation, NF-κBp65 nuclear translocation, and p65 DNA binding activity were not affected by inhibition of GSK-3β activity. However, GSK-3β inactivation inhibited transactivation activity of p65 by deacetylating p65 at lysine 310. Furthermore, we also demonstrated a functional interaction between mixed lineage kinase 3 (MLK3) and GSK-3β during LPS-induced TNF-α production in microglia. The phosphorylated levels of MLK3, MKK4, and JNK were increased upon LPS treatment. Decreasing GSK-3β activity blocked MLK3 signaling cascades through disruption of MLK3 dimerization-induced autophosphorylation, ultimately leading to a decrease in TNF-α secretion. Conclusion These results suggest that inactivation of GSK-3β might represent a potential strategy to downregulate microglia-mediated inflammatory processes.

Background Many cancer research studies have extensively examined the phosphatase and tensin homolog deleted from chromosome 10 (PTEN) pathway. There are only few reports that suggest that PTEN might affect pain; however, there is still a lack of evidence to show the role of PTEN for modulating pain. Here, we report a role for PTEN in a rodent model of neuropathic pain. Results We found that chronic constriction injury (CCI) surgery in rats could elicit downregulation of spinal PTEN as well as upregulation of phosphorylated PTEN (phospho-PTEN) and phosphorylated mammalian target of rapamycin (phospho-mTOR). After examining such changes in endogenous PTEN in neuropathic rats, we explored the effects of modulating the spinal PTEN pathway on nociceptive behaviors. The normal rats exhibited mechanical allodynia after intrathecal (i.t.) injection of adenovirus-mediated PTEN antisense oligonucleotide (Ad-antisense PTEN). These data indicate the importance of downregulation of spinal PTEN for nociception. Moreover, upregulation of spinal PTEN by i.t. adenovirus-mediated PTEN (Ad-PTEN) significantly prevented CCI-induced development of nociceptive sensitization, thermal hyperalgesia, mechanical allodynia, cold allodynia, and weight-bearing deficits in neuropathic rats. Furthermore, upregulation of spinal PTEN by i.t. Ad-PTEN significantly attenuated CCI-induced microglia and astrocyte activation, upregulation of tumor necrosis factor-α (TNF-α) and phospho-mTOR, and downregulation of PTEN in neuropathic rats 14 days post injury. Conclusions These findings demonstrate that PTEN plays a key, beneficial role in a rodent model of neuropathic pain.