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Background/Aims: Von Hippel-Lindau gene (VHL) has been reported as a tumor-suppressor gene in some cancers. However, the association between VHL promoter hypermethylation and renal cell carcinoma (RCC) remains to be clarified. We are the first to systematically integrate published papers to assess the role of hypermethylated VHL in RCC. Methods: The potential relevant papers were searched via PubMed, Embase, EBSCO, CNKI, and Wanfang databases. The overall odds ratio (OR) and corresponding 95% confidence interval (95% CI) were calculated to evaluate the relationship between VHL promoter hypermethylation and RCC. Results: Finally, a total of 1,998 RCC patients and 294 controls from 13 eligible articles were included in this meta-analysis. Under the fixed-effects model, the pooled OR from seven studies including 596 RCC and 294 nonmalignant samples showed that VHL promoter hypermethylation was significantly higher in cancer than in controls (OR = 7.93, 95% CI = 2.84-22.15, P < 0.001). Subgroup analysis based on ethnic population and testing method revealed that hypermethylated VHL had a significantly similar OR value in different races and detection methodologies. No significant association was found between hypermethylated VHL and tumor grade, tumor stage, tumor size, histological types, and lymph node status in cancer (all P > 0.05). In the current study, there was no evidence of publication bias as determined by Egger's test (all P > 0.05). Conclusions: In the investigated patients, VHL promoter hypermethylation, which may play an important role in carcinogenesis of RCC, is significantly associated with an increased risk of RCC. However, VHL promoter hypermethylation is not correlated with specific clinicopathological characteristics. Additional future studies are needed to confirm our results. [ABSTRACT FROM AUTHOR]

Background/Aims: Von Hippel-Lindau gene (VHL) has been reported as a tumor-suppressor gene in some cancers. However, the association between VHL promoter hypermethylation and renal cell carcinoma (RCC) remains to be clarified. We are the first to systematically integrate published papers to assess the role of hypermethylated VHL in RCC. Methods: The potential relevant papers were searched via PubMed, Embase, EBSCO, CNKI, and Wanfang databases. The overall odds ratio (OR) and corresponding 95% confidence interval (95% CI) were calculated to evaluate the relationship between VHL promoter hypermethylation and RCC. Results: Finally, a total of 1,998 RCC patients and 294 controls from 13 eligible articles were included in this meta-analysis. Under the fixed-effects model, the pooled OR from seven studies including 596 RCC and 294 nonmalignant samples showed that VHL promoter hypermethylation was significantly higher in cancer than in controls (OR = 7.93, 95% CI = 2.84- 22.15, P < 0.001). Subgroup analysis based on ethnic population and testing method revealed that hypermethylated VHL had a significantly similar OR value in different races and detection methodologies. No significant association was found between hypermethylated VHL and tumor grade, tumor stage, tumor size, histological types, and lymph node status in cancer (all P > 0.05). In the current study, there was no evidence of publication bias as determined by Egger's test (all P > 0.05). Conclusions: In the investigated patients, VHL promoter hypermethylation, which may play an important role in carcinogenesis of RCC, is significantly associated with an increased risk of RCC. However, VHL promoter hypermethylation is not correlated with specific clinicopathological characteristics. Additional future studies are needed to confirm our results. [ABSTRACT FROM AUTHOR]

Background/Aims: C-kit-positive cardiac stem cells (CSCs) may have potential as a treatment for cardiovascular disease. However, the low survival rates of c-kit-positive CSCs present a major challenge during the transplantation process. Methods: The hierarchical structure of the 3D cell scaffold was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and N2 adsorption-desorption isotherms. Analyses of the proliferation and migration performances of the IGF-1 scaffold on c-kit-positive CSCs were conducted by experiments including QuantiT PicoGreen dsDNA and transwell assays. Results: In this study, we synthesized for the first time a novel hierarchical macro-mesoporous silica material (denoted MS15-c) in a one-pot procedure for the release of insulin-like growth factor-1 (IGF-1) and a three-dimensional (3D) cell scaffold. Both macropores and mesopores were visible in MS15-c and enabled the sustained release of IGF-1, extending its half-life and enhancing CSC proliferation and migration. Proliferation and migration were detected by QuantiT PicoGreen dsDNA and transwell assays, respectively. Moreover, an in vivo experiment was conducted to detect heart function with the addition of MS15-c. The new strategy proposed in this paper may extend the bio-applications of 3D cell scaffolds, thus permitting the sustained release of growth factors and efficient promotion of cell proliferation. Conclusion: This work successfully demonstrated an effective strategy for the construction of MS15-c cell scaffolds with hierarchical macro-mesoporous structures. The macro-mesoporous structures gave cell scaffolds the ability to release a growth factor to facilitate cell growth, while the scaffold structure promoted cell proliferation. [ABSTRACT FROM AUTHOR]

Background/Aims: CircRNAs, as miRNA sponges, participate in many important biological processes. However, it remains unclear whether circRNAs can regulate lipid metabolism. This paper aims to study the molecular mechanism of fat deposition and provide useful information for the prevention and therapy of lipid metabolism-related diseases. Methods: CircRNA sequencing was performed to investigate the expression of circRNAs in the subcutaneous adipose tissues of Large White pig and Laiwu pig. The expression of circRNAs was further validated by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Furthermore, circRNA-microRNAs (miRNA)-mRNA interaction networks were constructed using bioinformatics tools. In addition, GO and KEGG enrichment analyses were performed for the target genes of circRNAs. Results: In the subcutaneous adipose tissue of Laiwu pig, 70 up-regulated circRNAs and 205 down-regulated circRNAs were identified. Two circRNAs (up-regulated circRNA_26852 and down-regulated circRNA_11897), the expressions of which were confirmed by qRT-PCR, were selected for subsequent analysis. CircRNA-miRNA-mRNA interaction networks were constructed for circRNA_26852 and its target genes as well as circRNA_11897 and its target genes. GO and KEGG enrichment analyses reveal that the target genes of circRNA_26852 and circRNA_11897 are enriched in pathways related to adipocyte differentiation and lipid metabolism, as well as in disease-related pathways. Conclusions: In this study, circRNA sequencing and bioinformatics technique were used to analyze, for the first time, the expression of circRNAs in the subcutaneous adipose tissues of Large White pig and Laiwu pig. It is inferred that circRNAs might regulate adipogenic differentiation and lipid metabolism. The results provide a theoretical basis for further study on fat deposition mechanism and provide potential therapy targets for metabolism-related diseases. [ABSTRACT FROM AUTHOR]

Background/Aims: The liver is a vital organ in vertebrates and has a wide range of functions, including glucose absorption, glycogen storage and glucose production. Fibroblast growth factor (FGF)-21 is a metabolic regulator that is primarily produced by the liver. In this paper, we studied the effect of FGF-21 on glucose metabolism in the liver. Methods: The glucose uptake of cells was detected by 2-Deoxy-d-[³H] glucose; the synergy between insulin and FGF-21 was evaluated. The mRNA expression of GLUT1-4, G6Pase and PEPCK was detected by real-time PCR. Glycogen synthesis was examined by the anthrone method. Blood samples to monitor glucose in db/db diabetic mice were obtained by tail snip. Glucose metabolism in the liver and adipose tissues was observed by fluorescence microscopy. Results: In this study, FGF-21 stimulated glucose uptake by liver cells in both a dose and time-dependent manner, and at the same time, FGF-21 specifically stimulated GLUT1 expression in the liver cells. Furthermore, FGF-21 demonstrated a synergistic effect with insulin on glucose absorption, which is in accordance with enhanced GLUT-1 and -4 expression. Treatment with FGF-21 increased glycogen storage in liver cells. Consistent with in vitro results, FGF-21 lowered the plasma glucose level and stimulated GLUT1 expression and glycogen synthesis in db/db diabetic mice. Simultaneously, FGF-21 inhibited the gene expression of G6Pase and PEPCK. Conclusion: Our results suggest that FGF-21 clears up plasma glucose by stimulating glucose absorption in the liver of diabetic animals and decreases glucose release from the liver by inhibiting gluconeogenesis. Overall, these data indicate that the liver is an important target organ of FGF-21 to regulate glucose metabolism. [ABSTRACT FROM AUTHOR]

Background/Aims: Glycine plays an important role in regulating hippocampal inhibitory/excitatory neurotransmission through activating glycine receptors (GlyRs) and acting as a coagonist of N-methyl-d-aspartate-type glutamate receptors. Activation of transient receptor potential vanilloid 4 (TRPV4) is reported to inhibit hippocampal A-type γ-aminobutyric acid receptor, a ligand-gated chloride ion channel. GlyRs are also ligand-gated chloride ion channels and this paper aimed to explore whether activation of TRPV4 could modulate GlyRs. Methods: Whole-cell patch clamp recording was employed to record glycine-activated current (IGly) and Western blot was conducted to assess GlyRs subunits protein expression. Results: Application of TRPV4 agonist (GSK1016790A or 5,6-EET) increased IGly in mouse hippocampal CA1 pyramidal neurons. This action was blocked by specific antagonists of TRPV4 (RN-1734 or HC-067047) and GlyR (strychnine), indicating that activation of TRPV4 increases strychninesensitive GlyR function in mouse hippocampal pyramidal neurons. GSK1016790A-induced increase in IGly was significantly attenuated by protein kinase C (PKC) (BIM II or D-sphingosine) or calcium/calmodulin-dependent protein kinase II (CaMKII) (KN-62 or KN-93) antagonists but was unaffected by protein kinase A or protein tyrosine kinase antagonists. Finally, hippocampal protein levels of GlyR α1 α2, α3 and β subunits were not changed by treatment with GSK1016790A for 30 min or 1 h, but GlyR α2, α3 and β subunits protein levels increased in mice that were intracerebroventricularly (icv.) injected with GSK1016790A for 5 d. Conclusion: Activation of TRPV4 increases GlyR function and expression, and PKC and CaMKII signaling pathways are involved in TRPV4 activation-induced increase in IGly. This study indicates that GlyRs may be effective targets for TRPV4-induced modulation of hippocampal inhibitory neurotransmission. [ABSTRACT FROM AUTHOR]

Background/Aims: Glycine plays an important role in regulating hippocampal inhibitory/ excitatory neurotransmission through activating glycine receptors (GlyRs) and acting as a co-agonist of N-methyl-d-aspartate-type glutamate receptors. Activation of transient receptor potential vanilloid 4 (TRPV4) is reported to inhibit hippocampal A-type γ-aminobutyric acid receptor, a ligand-gated chloride ion channel. GlyRs are also ligand-gated chloride ion channels and this paper aimed to explore whether activation of TRPV4 could modulate GlyRs. Methods: Whole-cell patch clamp recording was employed to record glycine-activated current (IGly) and Western blot was conducted to assess GlyRs subunits protein expression. Results: Application of TRPV4 agonist (GSK1016790A or 5,6-EET) increased IGly in mouse hippocampal CA1 pyramidal neurons. This action was blocked by specific antagonists of TRPV4 (RN-1734 or HC-067047) and GlyR (strychnine), indicating that activation of TRPV4 increases strychnine-sensitive GlyR function in mouse hippocampal pyramidal neurons. GSK1016790A-induced increase in IGly was significantly attenuated by protein kinase C (PKC) (BIM II or D-sphingosine) or calcium/calmodulin-dependent protein kinase II (CaMKII) (KN-62 or KN-93) antagonists but was unaffected by protein kinase A or protein tyrosine kinase antagonists. Finally, hippocampal protein levels of GlyR α1 α2, α3 and β subunits were not changed by treatment with GSK1016790A for 30 min or 1 h, but GlyR α2, α3 and β subunits protein levels increased in mice that were intracerebroventricularly (icv.) injected with GSK1016790A for 5 d. Conclusion: Activation of TRPV4 increases GlyR function and expression, and PKC and CaMKII signaling pathways are involved in TRPV4 activation-induced increase in IGly. This study indicates that GlyRs may be effective targets for TRPV4-induced modulation of hippocampal inhibitory neurotransmission. [ABSTRACT FROM AUTHOR]

Tumor-associated macrophages (TAMs) are one of the most abundant immune cells in the tumor microenvironment, and they play a pivotal role in prompting the various tumor growth. However, the role of TAMs in colorectal carcinoma (CRC) is controversial, because a few papers report that TAMs is beneficial to CRC patients. In this review, we discuss the good or bad roles of TAMs in CRC progression. Interestingly, recent studies provide strong evidence that TAMs facilitate CRC growth, but do not exert tumor suppressive activities. TAMs can stimulate CRC growth by altering extracellular matrix remodeling, tumor metabolism, angiogenesis, as well as the tumor microenvironment. Therefore, TAMs could serve as a target for CRC therapeutic treatment. [ABSTRACT FROM AUTHOR]

Background/Aims: Let-7b was dramatically reduced after a dicer knockout of mice with intestinal barrier function injuries. This paper aims to investigate the molecular mechanism of let-7b by targeting p38 MAPK in preventing intestinal barrier dysfunction. Methods: A total of 186 patients were enrolled, with 93 in the control group and 93 in the PRO group. Only 158 patients completed the entire study, whereas the others either did not meet the inclusion criteria or refused to participate. To further verify the role of let-7b, intestinal epithelial conditional knockout (IKO) mice of mmu-let-7b model were established. Serum let-7b, zonulin, IL-6, and TNF-α concentrations were measured by ELISA or quantitative RT-PCR. Permeability assay was done by ussing chamber. The apoptotic cells were identified using an In Situ Cell Death Detection Kit. Protein was detected by western blot. Results: Probiotics can lower infection-related complications, as well as increase the serum and tissue let-7b levels. P38 MAPK was identified as the target of let-7b, as verified by NCM460 cells. P38 MAPK expression was increased, whereas tight-junction (TJ) proteins were significantly decreased in let-7b IKO mice (both P<0.05). Negative regulation of p38 MAPK molecular signaling pathways was involved in the protective effects of let-7b on intestinal barrier function. Conclusion: Let-7b was identified as a novel diagnosis biomarker or a potential treatment target for preventing intestinal barrier dysfunction. [ABSTRACT FROM AUTHOR]

Background/Aims: Previous studies have shown that trolline possesses various forms of pharmacological activity, including antibacterial and antiviral potency. The present paper addressed the putative hepatoprotective effects of trolline. Methods: Rats received 2 ml/kg CCl4 (mixed 1:1 in peanut oil) intragastrically twice a week for 8 weeks to induce hepatic fibrosis. The animals were then treated with trolline for additional 4 weeks. Liver pathology and collagen accumulation were observed by hematoxylin-eosin and Masson's trichrome staining, respectively. Serum transaminase activity and collagen-related indicator level were determined by commercially available kits. NF-κB pathway activation was also examined. Moreover, the effects of trolline on hepatic stellate cell (HSC-T6) apoptosis, mitochondrial membrane potential (MMP), and autophagy were assessed. Results: Trolline significantly alleviated CCl4-induced liver injury and notably reduced the accumulation of collagen in liver tissues. Trolline treatment also markedly decreased inflammatory cytokines levels by inhibiting the NF-κB pathway. Trolline strongly inhibited HSC-T6 activation and notably induced cell apoptosis by modulating the Bax/Bcl-2 ratio, caspase activity, and MMP. Moreover, trolline significantly inhibited HSC-T6 autophagy, as evidenced by the decrease in the formation of autophagic vacuoles and the number of autophagosomes, by regulating the expression levles of LC3, Beclin-1, P62, Atg 5 and 7. Conclusion: Our study demonstrates that trolline ameliorates liver fibrosis, possibly by inhibiting the NF-κB pathway, promoting HSCs apoptosis and suppressing autophagy. [ABSTRACT FROM AUTHOR]

Background/Aims: Accumulating studies have reported that IGF-1R (Insulin-like growth factor-1 receptor) is aberrantly expressed in NSCLC (non-small cell lung cancer), but the role of IGF-1R in NSCLC remains controversial. The present paper assessed the precise role of IGF-1R in NSCLC. Methods: We comprehensively searched PubMed, EMBASE, and Web of Science in March 2017. Combined HRs and ORs were used to evaluate the prognostic and clinicopathological significance of IGF-1R in NSCLC respectively. Results: A total of 10 eligible studies including 8 on overall survival, and 10 on clinicopathological features were identified from the databases. The results showed that high expression of IGF-1R was associated with shorter OS (overall survival) of NSCLC patients (pooled HR 1.17,95 % CI 1.00-1.36). In addition, we found that IGF-1R was related to smoking status (OR=1.82, 95 % CI=1.35-2.44) and IGF-1R tended to be highly expressed in SCC (squamous cell carcinoma) (OR=3.40 95 % CI: 1.95-5.95). Conclusions: In summary, this meta-analysis revealed that high expression of IGF-1R was associated with poor prognosis in NSCLC. [ABSTRACT FROM AUTHOR]

Background/Aims: The aim of present study was to test the hypothesis that preconditioning with sodium hydrosulfide (NaHS) could enhance the capacity of migration, adhesion and proliferation of endothelial progenitor cells (EPCs) in vitro, and also could improve the efficacy of EPCs transplantation for re-endothelialization in nude mice with carotid artery injury. The paper further addressed the underlying mechanisms. Methods: EPCs were isolated from peripheral blood mononuclear cells of healthy male volunteers and the markers of EPCs were analyzed by flow cytometry. Thereafter, different concentrations of NaHS (25, 50, 100, 200 and 500 uM) were used for preconditioning EPCs. In vitro and in vivo migration, adhesion and proliferation as well as nitric oxide (NO) production of EPCs were evaluated. Carotid artery injury model was produced in nude mice and thereafter, NaHS-preconditioned EPCs were transplanted in order to evaluate their capacity of re-endothelialization. Results: Cellular immuno-staining showed that isolated cells expressed the key markers of EPCs. In vitro, EPCs proliferation rates and NO production were gradually increased in a NaHS-concentration dependent manner, while these benefits were blocked at a concentration of 500 uM NaHS. Similarly, the migration and adhesion rates of EPCs were also increased the most prominently at a concentration of 200 µM NaHS. In vivo, compared to the control group, treatment with NaHS-preconditioned EPCs significantly enhanced the capacity of re-endothelialization of EPCs. Fluorescent microscope revealed that there were more EPCs homing to the injury vessels in the NaHS-preconditioned EPCs group than the non-preconditioned group. With the administration of AMPK or eNOS inhibitors respectively, the above benefits of NaHS-preconditioning were abrogated. Conclusion: These results suggested that NaHS-preconditioning enhanced the biological function and re-endothelialization of EPCs through the AMPK/eNOS signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Colonic transit disorder-induced constipation is a major complication in diabetic patients. PDGFRα+ (platelet-derived growth factor receptor α-positive) cells play critical roles in the inhibitory regulation of colonic motility, and FOXO3 (forkhead transcription factor 3) has a broad range of biological functions. The present study was designed to investigate the relationship between FOXO3 and PDGFRα+ cell proliferation in streptozotocin (STZ)- induced diabetic mice. Methods: The major experimental techniques used in this paper are immunohistochemistry, quantitative RT-RCR and Western blotting for the evaluation of specific protein expression; ChIP assay for identifying the interaction between FOXO3 protein and the PDGFRα promotor; and lentiviral transfection for the overexpression of short hairpin RNAs (shRNAs) to down-regulate FOXO3. Results: In proximal colonic smooth muscle tissue of STZinduced diabetic mice, there was a significant increase in PDGFRα and Ki67 immunoreactivity. PDGFRa mRNA and protein expression levels were both significantly increased in colonic smooth muscle tissue, but PDGFRb expression was unchanged. Meanwhile, the expression of PDGF ligands, including both PDGFα and PDGFβ, was significantly increased in diabetic colonic smooth muscle tissue. In whole cell and nuclear extracts, the expression of FOXO3 protein was also significantly increased; however, the expression of P-FOXO3 (phosphorylated FOXO3) protein was significantly decreased. When NIH cells were incubated with 50 mmol/L glucose for 12 h, 24 h and 48 h, the expression of PDGFRa significantly increased, and in whole cell and nuclear extracts, the expression of FOXO3 protein was significantly increased. However, the expression of P-FOXO3 protein was significantly decreased. FOXO3 could bind to a site on the PDGFRα promoter, and the basal expression of PDGFRa was significantly reduced when endogenous FOXO3 expression was knocked down with FOXO3 short hairpin RNA (shRNA) in NIH cells. The expression of phosphorylated Akt was significantly down-regulated in diabetic colonic muscle tissue. Conclusions: These results suggest that diabetes-induced colonic PDGFRα+ cell proliferation is mediated by FOXO3 up-regulation. FOXO3 up-regulation may be induced by inhibiting the PI3K/Akt signaling pathway in STZ-induced diabetic mice. PDGFRα+ cell proliferation could be a new target for clinical therapy of diabetes-induced colonic transit disorder. [ABSTRACT FROM AUTHOR]

Background/Aims: The importance of copper in the metabolism of cancer cells has been widely studied in the last 20 years and a clear-cut association between copper levels and cancer deregulation has been established. Copper-64, emitting positrons and β-radiations, is indicated for the labeling of a large number of molecules suitable for radionuclide imaging as well as radionuclide therapy. Glioblastoma multiforme (GBM) is the CNS tumor with the worse prognosis, characterized by high number of recurrences and strong resistance to chemo-radio therapy, strongly affecting patients survival. We have recently discovered and studied the small molecule SI113, as inhibitor of SGK1, a serine/threonine protein kinase, that affects several neoplastic phenotypes and signaling cascades. The SI113-dependent SGK1 inhibition induces cell death, blocks proliferation, perturbs cell cycle progression and restores chemoradio sensibility by modulating SGK1-related substrates. In the present paper we aim to characterize the combined effects of 64CuCl2 and SI113 on human GBM cell lines with variable p53 expression. Methods: Cell viability, cell death and stress/authopagic related pathways were then analyzed by FACS and WB-based assays, after exposure to SI113 and/or 64CuCl2. Results: We demonstrate here, that i) 64CuCl2 is able to induce a time and dose dependent modulation of cell viability (with different IC50 values) in highly malignant gliomas and that the co-treatment with SI113 leads to ii) additive/synergistic effects in terms of cell death; iii) enhancement of the effects of ionizing radiations, probably by a TRC1 modulation; iv) modulation of the autophagic response. Conclusions: Evidence reported here underlines the therapeutic potential of the combined treatment with SI113 and 64CuCl2 in GBM cells. [ABSTRACT FROM AUTHOR]

Background/Aims: This paper aims to explore the effects of pyruvate kinase (PK) M2 gene silencing on the proliferation and apoptosis of colorectal cancer (CRC) LS-147T and SW620 cells. Methods: CRC LS-147T and sW620 cells highly expressing PKM2 were randomly selected by quantitative real-time polymerase chain reaction (qRT-PCR) and then assigned into the blank (no transfection), PKM2-shRNA (transfection with shRNA) and empty plasmid (transfection with empty plasmid) groups. Immunofluorescence was applied to detect PKM2 protein expression. qRT-PCR and Western blotting were conducted to assess mRNA and protein expression of PKM2, p53 and p21. The cell counting kit-8 (CCK-8) assay was used to assess cell proliferation. Flow cytometry was used to assess the cell cycle and apoptosis rate, and a senescence-associated β-galactosidase staining kit was used to assess cell senescence. Results: PKM2 exhibited high mRNA expression among CRC LS-147T and SW620 cells with remarkable protein expression noted in the cytoplasm and nucleus. The PKM2-shRNA group exhibited reduced PKM2 mRNA and protein expression, whereas p53 and p21 expression was increased compared with the blank and empty plasmid groups. Cell proliferation in PKM2-shRNA cells decreased significantly compared with the blank group and empty plasmid groups. The PKM2-shRNA group exhibited more cells in the G1 phase and fewer cells in the G2/M phase compared with the blank and empty plasmid groups. In addition, the PKM2-shRNA group exhibited significantly increased apoptosis rates andβ-galactosidase activity compared with the blank and empty plasmid groups. Conclusion: Our study demonstrates that PKM2 gene silencing suppresses proliferation and promotes apoptosis in LS-147T and SW620 cells. [ABSTRACT FROM AUTHOR]

Background/Aims: A high surface-to-volume ratio and a spectrin membrane-skeleton (MS) confer to the mammalian red blood cells (RBCs) their characteristic deformability, mechanical strength and structural stability. During their 120 days of circulatory life in humans, RBCs decrease in size, while remaining biconcave disks, owing to a coordinated decrease in membrane surface area and cell water. It is generally believed that part of the membrane is lost with the shedding of spectrin-free vesicles of the same type that can be obtained in vitro by different treatments. If this were true, an excess of MS would arise in old RBCs, with respect to the lipid bilayer. Aim of this paper was to investigate this aspect. Methods: Quantification of spectrin by electrophoretic methods was carried out in RBCs of different age. Results: Spectrin decreases, on a per cell basis, with RBC ageing. On the other hand, the membrane raft protein marker flotillin-2, while decreasing in the membrane of old cells, was found to be strongly depleted in the membrane of in vitro-induced vesicles. Conclusion: Part of the membrane-skeleton is probably lost together with part of the lipid bilayer in a balanced way. These findings point to a mechanism for the in vivo release of membrane that is different from that which is known to occur in vitro. [ABSTRACT FROM AUTHOR]

Background/Aims: The prognostic power of the levels of total CD44 and its isoform CD44v6 for patients with gastric cancer (GC) remains controversial. Therefore, our study aims to generalize the clinicopathological and prognostic significance of these two proteins in GC. Methods: A literature search of the PubMed, Web of Science and Embase databases was conducted to identify eligible studies. The odds ratio (OR) with a 95% confidence interval (CI) was used to assess the effects. Results: In all, 42 studies including 6,229 patients were included in this analysis. Total CD44 was mentioned in 21 papers, and the results showed that CD44 was positively correlated with the T category, the N category, distant metastasis, lymphatic invasion and TNM stage. Moreover, patients with CD44 overexpression had a lower 5-year overall survival (OS) rate (OR = 3.35, 95%CI = 1.83-6.13). CD44v6 was mentioned in 24 studies, with results that were similar to those for total CD44. However, total CD44 or CD44v6 expression was not correlated with tumor size and histological grade. Conclusion: High CD44 or CD44v6 expression levels were correlated with cancer progression and poor prognosis in patients with GC. Both CD44 and CD44v6 may be useful diagnostic or prognostic biomarkers for GC. [ABSTRACT FROM AUTHOR]

Background/Aims: Whether patients with RAS mutation metastatic colorectal cancer (mCRC) obtain benefits from bevacizumab added to first-line chemotherapy remains unclear. Methods: PubMed, Cochrane Systematic Reviews, the Cochrane Collaboration Central Register of Controlled Clinical Trials, ClinicalTrials.gov, and the American Society of Clinical Oncology and European Society for Medical Oncology databases were searched to identify abstracts for randomized controlled trials (RCTs) evaluating the efficacy of bevacizumab for the first-line treatment of patients with RAS mutations mCRC from inception to the end of April 2016. Hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) were estimated. Results: Ten eligible papers reporting six RCTs were included. In the network meta-analysis of patients with RAS mutations, bevacizumab + chemotherapy prolonged PFS compared with chemotherapy alone (HR 0.75, 95% CI 0.51-1.10), but the difference was not statistically significant. Bevacizumab + chemotherapy did not prolong OS compared with chemotherapy alone (HR 1.10, 95% CI 0.73-1.66). Conclusion: There was insufficient evidence to definitively state that patients with RAS mutations mCRC could benefit from bevacizumab combined with chemotherapy as first-line treatment. [ABSTRACT FROM AUTHOR]

Erythrocytes (RBCs) are extremely sensitive cells, and although they do not have nuclei and mitochondria, are important health indicators. This is particularly true because, during inflammation, whether it is systemic or chronic, the haematological system is constantly exposed to circulating inflammatory mediators. RBCs have a highly specialized and organized membrane structure, which interacts and reacts to inflammatory molecule insults, and undergo programmed cell death, similar to apoptosis, known as eryptosis. Over the past years, eryptosis studies have focussed on determining if membrane changes have occurred, particularly whether a phosphatidylserine (PS) flip, Ca2+ leakage into the cell, changes to ceramide and cell shrinkage have occurred. Mostly, flow cytometry is used, but confocal microscopy and ultrastructural studies also confirm eryptosis. Here, we provide a comprehensive overview of eryptosis, where we revisit the biochemical process of the process, review all literature in PUBMED, that is shown under the search word, "eryptosis", and also discuss current methodologies to determine the presence of eryptosis; included in the discussion of the methodologies, we discuss a pitfalls section for each method. This paper is therefore a comprehensive synopsis of current knowledge of eryptosis and discusses how RBCs may provide an essential in vivo cell model system to study not only inflammation in disease, but also track disease progression and treatment regimes. [ABSTRACT FROM AUTHOR]

Background/Aims: Coronary heart disease is characterized by vascular stenosis or occlusion resulting in myocardial ischemia, hypoxia and necrosis. In China, the combination of aspirin and Fufang Danshen Diwan (FDD), a traditional Chinese medicine formula, has been suggested in the treatment of coronary heart disease. There have been several studies comparing the effectiveness of aspirin alone and in combination with FDD to treat coronary artery disease; however, it remains unclear whether combined aspirin therapy is superior. This study was thus designed to clarify this issue through a systematic review and meta-analysis. Methods: Databases including PubMed, EMBASE, China National Knowledge Infrastructure (CNKI) database, Wanfang Data and VIP Information were searched. Papers were reviewed systematically by two researchers and analyzed using Cochrane software Revman 5.1. Results: Fourteen randomized controlled trials enrolling 1367 subjects were included. Metaanalyses revealed that aspirin in combination with FDD was significantly more effective at alleviating angina pectoris and improving electrocardiogram (ECG) results relative to aspirin therapy alone, reflected by the summary effects for the clinical markedly effective (OR = 2.45; 95% CI 1.95-3.08) and the total effective (OR = 3.92; 95% CI 2.87-5.36) rates. In addition, combined aspirin and FDD was significantly more efficacious than aspirin monotherapy at improving blood lipid levels, as indicated by the following outcomes: 1) reduction of TC level (SMD -1.12; 95% CI -1.49 to -0.76 ); 2) reduction of TG level (SMD -0.94; 95% CI -1.15 to -0.74 ); 3) reduction of LDL level (SMD -0.68; 95% CI -0.88 to -0.48); and 4) improvement of HDL level (SMD 0.52; 95% CI 0.04 to 0.99 ). No serious adverse events were reported in any of the included trials. Conclusion: The present meta-analysis demonstrated that aspirin in combination with FDD was more effective than aspirin alone for treating coronary heart disease. More full-scale randomized clinical trials with reliable designs are recommended to further evaluate the clinical benefits and long-term effectiveness of FDD for the treatment of coronary heart disease. [ABSTRACT FROM AUTHOR]

Background/Aims: Resveratrol and its derivate piceatannol are known to induce cancer cell-specific cell death. While multiple mechanisms of actions have been described including the inhibition of ATP synthase, changes in mitochondrial membrane potential and ROS levels, the exact mechanisms of cancer specificity of these polyphenols remain unclear. This paper is designed to reveal the molecular basis of the cancer-specific initiation of cell death by resveratrol and piceatannol. Methods: The two cancer cell lines EA.hy926 and HeLa, and somatic short-term cultured HUVEC were used. Cell viability and caspase 3/7 activity were tested. Mitochondrial, cytosolic and endoplasmic reticulum Ca2+ as well as cytosolic and mitochondrial ATP levels were measured using single cell fluorescence microscopy and respective genetically-encoded sensors. Mitochondria-ER junctions were analyzed applying super-resolution SIM and ImageJ-based image analysis. Results: Resveratrol and piceatannol selectively trigger death in cancer but not somatic cells. Hence, these polyphenols strongly enhanced mitochondrial Ca2+ uptake in cancer exclusively. Resveratrol and piceatannol predominantly affect mitochondrial but not cytosolic ATP content that yields in a reduced SERCA activity. Decreased SERCA activity and the strongly enriched tethering of the ER and mitochondria in cancer cells result in an enhanced MCU/Letm1-dependent mitochondrial Ca2+ uptake upon intracellular Ca2+ release exclusively in cancer cells. Accordingly, resveratrol/ piceatannol-induced cancer cell death could be prevented by siRNA-mediated knock-down of MCU and Letm1. Conclusions: Because their greatly enriched ER-mitochondria tethering, cancer cells are highly susceptible for resveratrol/piceatannol-induced reduction of SERCA activity to yield mitochondrial Ca2+ overload and subsequent cancer cell death. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to identify the different expression of circular RNAs (circRNAs) in the placental tissues of pregnant women with preeclampsia (PE) and to provide a new avenue of research regarding the pathological mechanisms of PE. Methods: In this study, we collected 40 placental tissues from PE patients and 35 placental tissues from gestational age-matched patients who gave premature birth. Arraystar circRNA Microarray Technology (KANGCHEN, Shanghai, China) was used to analyze the differential expression of circRNAs. According to the basic content of circRNAs in the two groups and their fold changes and due to the practicability of the designed divergent primers of each candidate circRNA, we selected three up-regulated circRNAs, hsa_circRNA_100782, hsa_circRNA_102682 and hsa_circRNA_104820, to validate the data. Real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was utilized to estimate the Ct values in both groups. We further evaluated the differences with a paired t-test and a receiver operating characteristic (ROC) curve. Results: Many circRNAs were found to be differentially expressed in PE placental tissues versus their controls; of these, 143 circRNAs were up-regulated and 158 were down-regulated. The expression levels of hsa_circRNA_100782 (p < 0.05), hsa_circRNA_102682 (p < 0.05), and hsa_circRNA_104820 (p < 0.0001) were validated as significantly up-regulated in the experimental group compared with the controls. Finally, we performed a literature comparison to forecast the possible mechanisms of circRNA function during PE. Conclusion: circRNA expression significantly differed in placental PE tissues compared with controls. According to the circRNA microarray results and the existing papers, circRNAs may contribute to the pathogenesis of PE by acting as miRNA sponges; this possibility requires additional investigation in future studies. [ABSTRACT FROM AUTHOR]

Background/Aims: The risk of heart disease is higher in males than in females. However, this advantage of females declines with increasing age, presumably a consequence of decreased estrogen secretion and malfunctioning of the estrogen receptor. We previously demonstrated that 17β-estradiol (E2) prevents cardiomyocyte hypertrophy, autophagy and apoptosis via estrogen receptor α (ERα), but the effects of ERβ on myocardial injury remained elusive. The present paper thus, investigated the cardioprotective effects of estrogen (E2) and ERβ against hypoxia-induced cell death. Methods: Transient transfection of Tet-On ERβ gene construct was used to overexpress ERβ in hypoxia-treated H9c2 cardiomyoblast cells. Results: Our data revealed that IGF1R, Akt phosphorylation and Bcl-2 expression are enhanced by ERβ in H9c2 cells. Moreover, ERβ overexpression reduced accumulation of hypoxia-related proteins, autophagy-related proteins and mitochondria-apoptotic proteins and enhanced the protein levels of Bcl-2, pAkt and Bad under hypoxic condition. In neonatal rat ventricular myocytes (NRVMs), we observed that hypoxia induced cell apoptosis as measured by TUNEL staining, and E2 and/or ERβ could totally abolish hypoxia-induced apoptosis. The suppressive effects of E2 and/or ERβ in hypoxia-treated NRVMs were totally reversed by ER antagonist, ICI. Taken together, E2 and/or ERβ exert the protective effect through repressed hypoxia-inducible HIF-1α, BNIP3 and IGFBP-3 levels to restrain the hypoxia-induced autophagy and apoptosis effects in H9c2 cardiomyoblast cells. Conclusion: The results suggest that females probably could tolerate better prolonged hypoxia condition than males, and E2/ERβ treatment could be a potential therapy to prevent hypoxia-induced heart damage.' © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aim: Glycyrrhizin (GL) is an important derivative of certain herbal medicines used in Asian countries. Currently, GL is used to treat hepatitis and allergic disease worldwide because of its anti-viral and anti-allergy effects. In addition to these prominent functions, GL likely regulates cellular functions such as tumor cell growth and cellular immunity. However, how GL affects the keratinocyte inflammation response remains poorly understood. The current paper investigates the effect of GL on psoriasis and explores the mechanisms involved. Methods: We used an in vitro cell model of tumor necrosis factor (TNF)-α-induced keratinocyte inflammation and the topical application of imiquimod (IMQ) using an animal model (mouse skin) of IMQ-induced psoriasis-like inflammation (IPI) to investigate the effect of GL on skin inflammation. Cell viability was analyzed using the Cell Counting Kit-8 (CCK8). Carboxyfluorescein succinimidyl ester (CFSE) labeling was used to trace monocyte adherence to keratinocytes. A Western blot analysis was used to detect the expression of intercellular adhesion molecule 1 (ICAM-1) and the activation of the nuclear factor (NF)-κB/mitogen-activated protein kinase (MAPK) signaling pathway. A modified version of the Psoriasis Area Severity Index (PASI) was used to monitor disease severity. Hematoxylin and eosin (H&E) staining was used to observe pathological changes. An immunohistochemistry (IHC) analysis was used to detect ICAM-1 expression in mouse skin. Results: GL treatment significantly reduced the levels of ICAM-1 in TNF-α-stimulated HaCaT cells, inhibited subsequent monocyte adhesion to keratinocytes, and suppressed the nuclear translation and phosphorylation of p65 following the degradation of inhibitor κB (IκB). GL treatment blocked the phosphorylation of extracellular signal-regulated kinase (ERK)/p38 MAPK. GL effectively delayed the onset of IPI in mice and ameliorated ongoing IPI, thereby reducing ICAM-1 expression in epidermal tissues. Conclusions: These results demonstrate that GL treatment ameliorates skin inflammation by inhibiting ICAM-1 expression via interference with the ERK/p38 MAPK and NF-κB signaling pathways in keratinocytes. Therefore, GL can be used as an anti-psoriasis drug. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Acute liver failure (ALF), known as a rapid and severe clinical syndrome, can induce multiple organ dysfunction and failure. It was noticed that Kupffer cells activation at the initial phase was involved in some intense inflammatory responses in the pathogenesis of ALF. However, detailed regulation mechanism of Kupffer cells activation during ALF is still obscured. Present study aimed to discover the potential regulator and explore deeper information of Kupffer cells activation at the early stage of ALF. Methods: The mouse model of ALF was established by Concanavalin A injection. Dynamic immunological statuses of Kupffer cells at the early stage of ALF were exhibited by detecting typical cytokines. The expression of inflammasome AIM2 was measured in both RNA and protein level. Its role of affecting Kupffer cells activation during ALF by inducing IL-1β production was identified by RNA interference in vitro. Moreover, the expression of miR-223 in vivo was measured by q-PCR and its role in regulating Kupffer cells activation during Con A induced ALF was determined by RNAs transfection. Results: Present study showed that mass production of IL-1β from isolated Kupffer cells in Con A treated mice might be the main driving force of Kupffer cells pro-inflammatory activation during ALF. The role of AIM2 in affecting pro-inflammatory activation of Kupffer cells by inducing IL-1β production was crucial to ALF. Further study found that miR-223 acted as a regulator in Kupffer cells activation at the early stage of ALF by influencing IL-1β production via AIM2 pathway. Conclusion: For the first time, this paper demonstrated that miR-223 acted to inhibit IL-1β production via AIM2 pathway, suppressing Kupffer cells pro-inflammatory activation at the early stage of ALF. Thus, it played an important role in the pathogenesis of ALF. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Na+/H+ exchanger 1 (NHE1) is an important regulator of intracellular pH (pHi). High pHi is required for cell proliferation and differentiation. Our previous study has proven that the pHi of mesenchymal stem cells is higher than that of normal differentiated cells and similar to tumor cells. NHE1 is highly expressed in both mesenchymal stem cells and tumor cells. Targeted inhibition of NHE1 could induce differentiation of K562 leukemia cells. In the present paper we explored whether inhibition of NHE1 could induce differentiation of mesenchymal stem cells. Methods: MSCs were obtained from human umbilical cord and both the surface phenotype and functional characteristics were analyzed. Selective NHE1 inhibitor cariporide was used to treat human umbilical cord-derived mesenchymal stem cells (hUC-MSCs). The pHi and the differentiation of hUC-MSCs were compared upon cariporide treatment. The putative signaling pathway involved was also explored. Results: The pHi of hUC-MSCs was decreased upon cariporide treatment. Cariporide up-regulated the osteogenic differentiation of hUC-MSCs while the adipogenic differentiation was not affected. For osteogenic differentiation, β-catenin expression was up-regulated upon cariporide treatment. Conclusion: Decreased pHi induced by cariporide differentially contributes to hUC-MSCs differentiation. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: We previously reported that porcine intramuscular (i.m.) preadipocytes were different from subcutaneous (s.c.) preadipocytes on cell differentiation and lipid accumulation, but the underlying mechanisms remained unknown. The paper aims to investigate the underlying mechanisms by comparing the differences between i.m. and s.c. preadipocytes in glucose utilization, lipid metabolism, and the role of BMP signaling pathway. Methods: Experiments were performed in porcine primary i.m. and s.c. preadipocytes in culture. The mRNA and protein expression patterns were determined respectively by Quantitative real-time PCR and Western blot. Cytosolic triglycerides were examined by triglyceride assay. Results: The i.m. preadipocytes consumed more glucose by expression of GLUT1 and s.c. preadipocytes mainly utilized exogenic fatty acids for lipid synthesis by expression of LPL and FAT. Meanwhile, the expression of genes related to lipogenesis and lipolysis in s.c. preadipocytes increased more quickly than those in i.m. preadipocytes. The expression patterns of the genes involved in BMP-Smad signaling pathway were consistent with those of the genes participated in adipocytes differentiation in both i.m. and s.c. preadipocytes. Exogenous BMP2 significantly increased, whereas Noggin and Compound C, remarkablely decreased the triglycerides content in i.m. preadipoytes, without affecting s.c. preadipocytes. BMP2 shRNA significantly reduced the mRNA levels of the downstream genes of BMP-Smad signaling pathway and PPARγ in both i.m. and s.c. preadipocytes. Conclusion: These findings suggested that the differentiation and lipid accumulation differences between i.m. and s.c. preadipocytes might be caused by the different manners of glucose utilization, lipid metabolism and the BMP-Smad signaling pathway. The special feature of i.m. adipocytes implied that these cells might be a potential target for treatment of diabetes. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Adipose microenvironment is involved in signaling pathways that influence prostate cancer (PCa) progression. However, the role of human periprostatic adipose tissue (PPAT) from patients with benign prostatic hyperplasia (BPH) has not been studied and compared to that of PPAT from PCa patients. The aim of this paper was to investigate the influence of factors derived from both PPATs on the behavior of androgen-dependent and castration resistant PCa cells. Methods: PPAT conditioned media (CM) were obtained from tissue samples from patients with clinically primary PCa (TPPAT) or BPH (BPPAT). Ceil adhesion, proliferation, migration and metalloproteinase expression were evaluated following exposure of LNCaP (androgen dependent) and PC3 (androgen independent) prostate cancer cell lines to BPPAT or TPPAT CM. Results: Proliferation or motility of LNCaP or PC3 cells were not significantly affected by TPPAT or BPPAT CM. The number of LNCaP but not PC3 cells attached to components of TPPAT CM significantly decreased compared to cells attached to BPPAT CM. PPAT produced and released pro-MMP-9. Zymograms demonstrated that TPPAT CM induced a significant increase in pro-MMP-9 activity compared to BPPAT CM in LNCaP cells but not in PC3 cells. Conclusions: We conclude that TPPAT released factors, such as pro-MMP-9, could induce the invasive capacity of LNCaP cells and speculate that PPAT derived factors could, in the early stages of prostate cancer, modulate disease progression. [ABSTRACT FROM AUTHOR]

Myocardial ischemia und subsequent reperfusion is followed by a complex sequence of pathophysiological responses involving inflammatory cell infiltration and cytokine release as well as postinfarction wound healing and myocardial tissue remodeling. With the development of gene targeted mice the contribution of individual gene products to the pathophysiology of myocardial ischemia and reperfusion can be defined leading to an increasing interest in the widely-used mouse model of myocardial infarction. This methological paper describes in detail the required equipment, surgical instruments, drugs and additional material, the methods of anesthesia and analgesia, the procedures involved in preparation of the animal, tracheotomy, intubation, thoracotomy, occlusion of the left descending artery, removal of the heart, determination of infarct size, analysis of cardiac functional parameters with echocardiography and magnetic resonance imaging (MRI) as well as determination of the morphological consequences utilizing gelatin zymography, histology and immunohistochemistry. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background and purpose: Dinoflagellates from the genus Ostreopsis have been related to the production of palytoxin and analogues. Based on that, this paper describes functional studies of crude extracts from Ostreopsis cf. siamensis collected in the Mediterranean Sea in order to biochemically characterize their toxic compounds. Methods: We compared the effects of 5 crude dinoflagellates extracts with a commercially available palytoxin and a purified Ostreopsis ovata extract on metabolic activity, membrane potential, and cytosolic calcium levels by using fluorescent dyes. Results: All the extracts resulted to be neurotoxic. In addition, all of them induced a membrane depolarization and a calcium increment that were abolished when preincubating with ouabain, an inhibitor of the Na+/K+ pump. Conclusion: The effects observed were quite close to those induced by palytoxin and the Ostreopsis ovata extract as well, suggesting that Ostreopsis cf. siamensis is actually producing palytoxin-like compounds that are highly toxic and functionally active. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Several types of K+ channels have been identified in epithelial cells. Among them high conductance Ca2+-activated K+ channels (BK channels) are of relevant importance for their involvement in regulatory volume decrease (RVD) response following hypotonic stress. The aim of the present work was to investigate the functional and molecular expression of BK in the eel intestine, which is a useful experimental model for cell volume regulation research. In the present paper using rat BK channel-specific primer, a RT-PCR signal of 696 pb cDNA was detected in eel intestine, whole nucleotide sequence showed high similarity (83%) to the alpha subunit of BK channel family. BK channel protein expression was verified by immunoblotting and confocal microscopy, while the functional role of BK channels in epithelial ion transport mechanisms and cell volume regulation was examined by electrophysiological and morphometric analysis on the intact tissue. BKCa channels appeared to be localized along all the plasma membrane of the enterocytes; the apical part of the villi showed the most intense immunostaining. These channels were silent in basal condition, but were activated on both membranes (apical and basolateral) by increasing intracellular Ca2+ concentration with the Ca2+ ionophore ionomycin (1μM). BKCa channels were also activated on both membranes by hypotonic swelling of the epithelium and their inhibition by 100 nM iberiotoxin (specific BKCa inhibitor) abolished the Regulatory Volume Decrease (RVD) of the intestinal cells after hypotonic swelling. In conclusion, our results demonstrated the molecular and functional expression of high conductance Ca2+ -activated K+ channels in eel intestine; the physiological role of these channels is mainly related to the RVD response of the epithelial cells following hypotonic swelling. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

KATP channel activity influences beta cell Ca2+ homeostasis by regulating Ca2+ influx through L-type Ca2+ channels. The present paper demonstrates that loss of KATP channel activity due to pharmacologic or genetic ablation affects Ca2+ storage in intracellular organelles. ATP depletion, by the mitochondrial inhibitor FCCP, led to Ca2+ release from the endoplasmic reticulum (ER) of wildtype beta cells. Blockade of ER Ca2+ ATPases by cyclopiazonic acid abolished the FCCP-induced Ca2+ transient. In beta cells treated with KATP channel inhibitors FCCP elicited a significantly larger Ca2+ transient. Cyclopiazonic acid did not abolish this Ca2+ transient suggesting that non-ER compartments are recruited as additional Ca2+ stores in beta cells lacking KATP channel activity. Genetic ablation of KATP channels in SUR1KO mice produced identical results. In INS-1 cells transfected with a mitochondrial-targeted Ca2+-sensitive fluorescence dye (ratiometric pericam) the increase in mitochondrial Ca2+ evoked by tolbutamide was 5-fold larger compared to 15 mM glucose. These data show that genetic or pharmacologic ablation of KATP channel activity conveys Ca2+ release from a non-ER store. Based on the sensitivity to FCCP and the property of tolbutamide to increase mitochondrial Ca2+ it is suggested that mitochondria are the recruited store. The change in Ca2+ sequestration in beta cells treated with insulinotropic antidiabetics may have implications for beta cell survival and the therapeutic use of these drugs. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Serum- and glucocorticoid-inducible kinase-1 (SGK1) increases CFTR Cl currents in Xenopus oocytes by an unknown mechanism. Because SGK increases the plasma membrane expression of other ion channels, the goal of this paper was to test the hypothesis that SGK1 stimulates CFTR Cl currents by increasing the number of CFTR Cl channels in the plasma membrane. Methods: CFTR Cl currents were measured in Xenopus oocytes by the two-electrode voltage clamp technique, and CFTR in the plasma membrane was determined by laser scanning confocal microscopy. Results: wt-SGK1 stimulated CFTR Cl currents by 42% and increased the amount of CFTR in the plasma membrane by 35%. A kinase-dead SGK mutant (K127N) had a dominant-negative effect on CFTR, reducing CFTR Cl currents by 38%. In addition, deletion of the C-terminal PDZ-interacting motif (SGK1-ΔSFL) increased CFTR Cl currents by 108%. Thus, SGK1-ΔSFL was more effective than wt-SGK1 in stimulating CFTR Cl currents. Neither wt-SGK nor the K127N mutant had any effect on Cl currents in oocytes when expressed alone in the absence of CFTR. Conclusion: SGK1 stimulates CFTR Cl currents in Xenopus oocytes by increasing the number of channels in the plasma membrane. Moreover, the effect of SGK may be mediated by protein-protein interactions involving the PDZ interacting motif. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

During kidney development a multitude of tubular portions is formed. Little knowledge is available by which cellbiological mechanism a cluster of embryonic cells is able to generate the threedimensional structure of a tubule. However, this know-how is most important in tissue engineering approaches such as the generation of an artificial kidney module or for the therapy of renal diseases using stem cells. To obtain cellbiological insights in parenchyme development we elaborate a new technique to generate under in vitro conditions renal tubules derived from the embryonic cortex of neonatal rabbits. The aim of the experiments is to establish a specific extracellular environment allowing optimal threedimensional development of renal tubules under serum-free culture conditions. In the present paper we demonstrate features of the renal stem cell niche and show their isolation as intact microcompartiments for advanced tissue culture. Perfusion culture in containers exhibiting a big dead fluid volume results in the development of a flat collecting duct (CD) epithelium at the surface of the tissue explant. In contrast, by fine-tuning the dead fluid volume within a perfusion culture container by an artificial interstitium made of a polyester fleece shows the generation of tubules. It is an up to date unknown morphogenetic information which tells the cells to form tubular structures. [ABSTRACT FROM AUTHOR]

Background/Aims: In thyroid cells, the intracellular pH plays a key role in the control of the iodide uptake, since iodide accumulation is associated with an intracellular acidification. In the present paper we studied the kinetic proprieties of the Na+/H+ antiporter (NHE) and the molecular expression of different NHE isoforms in rat thyroid PC-Cl3 cells. In addition the intracellular buffer capacity was also evaluated. Methods: pHi was measured using the pH sensitive fluorescent dye BCECF-AM. Amiloride, 5-(N,NDimethyl) hydrochloride was used to inhibit NHE activity. RT-PCR and western blot analyses were used to study the expression of NHE mRNA and protein isoforms. Results: PC-Cl3 cells shown a resting pHi, in the absence of CO2/HCO3 -, of 6.94 ± 0.1; after an acid load PC-Cl3 cells recovered toward resting pHi value, using a Na-dependent H+ extrusion mechanisms which was amiloride sensitive (Ki = 23 μM). The kinetic parameters were K(Na)app = 10 ± 2 mM and Vmax = 0.23 ± 0.02 ΔpH/min x 105 cells. NHE1, NHE2 and NHE3 were expressed at the mRNA level as well as at the protein level. Conclusion: PC-Cl3 cells express a functional Na/H exchange activity and different isoforms (NHE1, NHE2 and NHE3) are expressed in the plasma membrane. [ABSTRACT FROM AUTHOR]

The dolichyl-phosphate alpha-N-acetylglucosaminephosphotransferase 2 (Dpagt2) gene in the mouse has a housekeeping promoter, and its expression is regulated during the development and hormonally modulated lactogenesis of the mammary gland. Previous studies showed that the transcription of the mouse mammary Dpagt2 gene is stimulated by the lactogenic hormones, insulin, glucocorticoid receptor (GR), and prolactin. Transcription factors which bind to the Dpagt2 gene promoter region can influence the expression level of the Dpagt2 gene. It is supposed that the Dpagt2 gene promoter region (bases pairs -1462 to -5) maybe contain 10 putative STAT (signal transducer and activator of transcription) binding sites: TTN(5/6) AA. In order to identify the STAT factors involved in the transcription of the GPT gene, 32P labeling probes and lactating mouse nuclear extracts were prepared. Electrophoretic Mobility Shift Assays (EMSA) show that the region (bases pairs -386 to -322, where there is a STAT binding site, TTTCAAAAA) binds to STAT5a, not to glucocorticoid receptor (GR) or other STAT factors. The involvement of STAT5a in regulating the expression of the mouse Dpagt2 gene was further investigated by transient transfections of various Dpagt2 promoter/luciferase (Luc) constructs into COS 7 cells. The results showed that co-transfection of STAT5a or prolactin receptor can enhance Dpagt2 promoter activities in the promoter construct pGL-MX6 (from base pairs -386 to -5), but not in the promoter construct pGLMX7 (from base pairs -322 to -5). This paper first reports that STAT5a is involved in the binding between -386 and -322 base pairs of the Dpagt2 gene promoter and stimulates the expression of the Dpagt2 gene transcription in the mouse lactating mammary gland. [ABSTRACT FROM AUTHOR]

Background/Aims: High glucose-induced oxidative stress and inflammatory responses play an important role in painful diabetic neuropathy by activating the TLR4/NFκB signal pathway. Schwann cells (SCs) are integral to peripheral nerve biology, contributing to saltatory conduction along axons, nerve and axon development, and axonal regeneration. SCs provide a microenvironment favoring vascular regeneration but their low survival ratio in hyperglycemic conditions suppress the function to promote nerve growth. Nuclear factor erythroid 2-related factor 2 (Nrf2) promotes remyelination after peripheral nerve injury. The aim of this study was to identify the role of Nrf2 in SC-mediated functional recovery after sciatic nerve injury. Methods: We compared plasma inflammatory factors in diabetic patients (DN) with/without diabetic peripheral neuropathy (DPN) and assessed whether Nrf2 expression in SCs could repair peripheral nerve injury in a rat model. Nrf2, TLR4/NFκB signal pathway and apoptosis relative protein expression were detected by western blot. Apoptosis and angiogenesis were determined by immunofluorescence and tubule formation assay, respectively. Regenerated nerves were determined by transmission electron microscope. Results: Higher levels of inflammatory factors and VEGF expression were found in DPN patients. Cellular experiments indicate that Nrf2 expression inhibits hyperglycemia-induced apoptosis and promotes angiogenesis by regulating the TLR4/NFκB signal pathway. Animal experiments show that nerve conduction velocity, myelin sheath thickness, and sciatic vasa nervorum are restored with transplantation of SCs overexpressing Nrf2. Conclusions: Taken together, the high survival ratio of SCs in a DPN rat model indicates that overexpression of Nrf2 restores nerve injury. [ABSTRACT FROM AUTHOR]

Background/Aims: SMAD7 is a key inhibitor of transforming growth factor β (TGFβ) receptor signaling, which regulates the alteration of cancer cell invasiveness through epithelialmesenchymal cell conversion. Dysfunction of protein ubiquitination plays a critical role in carcinogenesis, whereas the involvement a deubiquitinating enzyme, cylindromatosis gene (CYLD), in the tumor invasion of oral squamous cell carcinoma (OSCC) is unknown. Methods: Here, we studied the role of CYLD in regulation of OSCC cell invasion, using clinic specimens and cell lines. We modified SMAD7 levels in OSCC cells, and examined its effects on CYLD mRNA and protein levels by RT-qPCR and by Western blot, respectively. We also modified CYLD levels in OSCC cells, and examined its effects on SMAD7 mRNA and protein levels by RT-qPCR and by Western blot, respectively. Then, we examined the cell invasiveness in CYLD and/or SMAD7-modified OSCC cells in a transwell cell invasion assay. Results: We found that the levels of CYLD and SMAD7 were significantly decreased in OSCC specimens, compared to the paired normal tissue. Metastatic OSCC appeared to contained lower levels of CYLD and SMAD7. Moreover, CYLD and SMAD7 levels strongly correlated in OSCC specimens. Low CYLD levels were associated with poor patients' survival. Moreover, SMAD did not regulate CYLD, but CYLD regulated the levels of SMAD7 in OSCC cells. Furthermore, CYLD overexpression inhibited SMAD7-mediated cell invasion, while CYLD depletion increased SMAD7-mediated cell invasion in OSCC cells. Conclusion: Suppression of CYLD in OSCC cells may promote SMAD7-mediated cancer invasion. Thus, CYLD appears to be an intriguing therapeutic target to prevent OSCC metastases. [ABSTRACT FROM AUTHOR]

Objective: C-Jun plays a critical role in ultraviolet A (UVA) irradiation-induced photoaging. The exact mechanisms by which UVA irradiation up-regulates c-Jun expression in human dermal fibroblasts (HDFs) are still not completely understood. We undertook this study to investigate whether microRNA-155 (miR-155) directly regulates the expression of c-Jun in HDFs in vitro. Methods: Expression of c-Jun mRNA and protein and miR-155 in UVA-irradiated HDFs were detected using quantitative real-time RT-PCR and Western blotting. Luciferase reporter assays were performed to examine whether a miR-155 binding site in the 3′-untranslated region (3′-UTR) of the c-Jun gene is responsible for miR-155-mediated c-Jun regulation in HEK293A cells, and expression of c-Jun mRNA and protein in UVA non-exposed and exposed HDFs trasfected with a miR-155 mimic or a miR-155 inhibitor was detected by quantitative real-time RT-PCR and Western blotting. Results: Expression of miR-155 was markedly reduced and that of c-Jun mRNA and protein was significantly up-regulated in UVA-irradiated HDFs. Luciferase reporter assays indicated that c-Jun is a direct target of miR-155 in HEK293A cells. In both UVA non-exposed and exposed HDFs, miR-155 mimic decreased c-Jun protein levels, while miR-155 inhibitor increased c-Jun protein levels, but both had no effect on c-Jun mRNA expression, which suggest that miR-155-induced c-Jun inhibition occurs at the post-transcriptional level. Conclusions: Our results demonstrate that miR-155 directly controls c-Jun expression in HDFs at the post-transcriptional level and might function as a protective miRNA in HDFs. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: HO-1 and EETs are functionally linked and their interactions influence body weight, insulin sensitivity, and serum levels of inflammatory cytokines in metabolic syndrome phenotype of HO-2 null mice. The HO-2 isozyme is essential for regulating physiological levels of ROS. Recent studies have suggested a potential role of EET in modifying adipocyte differentiation through up-regulation of HO- 1-adiponectin-AkT signaling in human mesenchymal stem cells (MSCs). Our aim was to examine the consequences of HO deficiency on MSC-derived adipogenesis in vitro using MSC derived from HO-2 null and WT mice in vivo. Methods: Four-month-old HO-2 null (HO-2-/-) and B6/129SF2/J (WT) mice were divided into three groups (four mice/group): WT, HO- 2-/-, and HO-2-/- +CoPP. Adipogenesis was performed on purified MSC-derived adipocytes cultured in adipogenic differentiation media and an EET-agonist was added every 3 days. Results: HO-2 depletion of MSC adipocytes resulted in increased adipogenesis (p<0.01) and increased levels of inflammatory cytokines including (TNF)-alpha (p<0.05), (MCP)-1 (p<0.05), and (IL-1)-beta (p<0.05). These results were accompanied by decreases in HO-1 (p<0.05) and subsequently EET and HO activity (p<0.05). Upregulation of HO-1 resulted in decreased MSC-derived adipocyte differentiation, decreased production of TNF-alpha and MCP-1 and increased levels of adiponectin (p<0.05). Cyp2J5 (p<0.05), HO- 1 (p<0.05), and adiponectin mRNA levels (p<0.05) were also decreased in visceral adipose tissue isolated from HO-2 null compared to WT mice. EET agonist stimulation of MSC adipocytes derived from HO-2 null mice yielded similar results. Conclusion: Increased levels of EET and HO-1 are essential for protection against the adverse effects of adipocyte hypertrophy and the ensuing metabolic syndrome. These results offer a portal into therapeutic approaches for the prevention of the metabolic syndrome. [ABSTRACT FROM AUTHOR]

Backgrounds: RNA-binding protein QKI is abundantly expressed in the brain and heart. The role of QKI in the nervous system has been well characterized, but its function in cardiac muscle is still poorly understood. The present study was to investigate the role of QKI in ischemia/reperfusion-induced apoptosis in cardiomyocytes. Methods: A simulated ischemia/reperfusion model was established in neonatal cardiomyocytes and adult rat heart. After QKI5 or QKI6 was expressed by adenovirus and QKI was knocked down QKI by RNAi in the cardiomyocytes, RT-PCR, western blot and immunofluorescence staining were applied to detect gene expression alterations. Apoptosis was evaluated by PARP degradation, DNA fragmentation (DNA laddering) and flow cytometry. Results: Our study demonstrated that both QKI5 and QKI6 were present in cardiomyocytes, while QKI5 expression was greatly inhibited by simulated ischemia/reperfusion. Knocking down endogenous QKI by RNAi enhanced cell susceptibility to apoptosis, whereas overexpression of either QKI5 or QKI6 suppressed IR-induced apoptosis substantially. The pro-apoptotic transcription factor FoxO1, a potential QKI target, was induced by ischemia/reperfusion at both total amount and nuclear distribution. Accordingly, FOXO1 downstream target genes were negatively affected by the presence of QKI with IR treatment. Conclusion: In summary, our study supports that both QKI-5 and 6 are anti-apoptotic proteins in cardiomyocytes, favoring cardiac survival via antagonizing the elevation of some pro-apoptotic factors in cardiac injury. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In order to clarify the functional role of ionotropic purinergic (P2X) receptors in pancreatic β-cells, we examined the effect of several P2 receptor agonists and antagonists on insulin secretion by mouse pancreatic islets, mouse Beta-TC6 cell proliferation and survival of dispersed islet cells in culture. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed the expression of mRNAs of P2X4 receptor in mouse islets and P2X1, P2X2, P2X3, P2X4, P2X5 and P2X7 receptors in Beta-TC6 cells. The presence of P2X4 receptor proteins in islets and Beta-TC6 cells was confirmed by immunofluorescent staining and Western blot analysis. We have previously found that the functional P2Y1 receptor but not P2Y2 and P2Y4 receptors was present in islets. In this study we found that a nonspecific P2 receptor agonist, ATP (1 μM) stimulated insulin secretion by islets in the presence of high glucose (20 mM) in culture. The effect of ATP was partially inhibited by a P2 receptor antagonist PPADS as well as a P2Y1 receptor antagonist MRS2179. In addition, a P2X4 receptor potentiator ivermectin per se augmented glucose-induced insulin secretion and slightly potentiated the effect of ATP. These results suggested the involvement of P2Y1and P2X receptors. We also found that ATP inhibited proliferation of Beta-TC6 cells in a concentration-dependent manner during 72 h culture. The inhibitory effect of ATP was completely reversed by PPADS and partially by treating cells with small interfering RNA targeted for P2X4 receptor mRNA. Furthermore, we found that the phosphorylation of the extracellular signal-regulated kinase 1 and 2 (ERK1/2) was suppressed by treatment with ATP in Beta-TC6 cells. In addition, we found that ATP reduced the cell viability and DNA synthesis of islet cells in culture. The effect of ATP on the cell viability was blocked by PPADS or MRS2179. These results suggested that P2X receptors as well as the P2Y1 receptor played a role in the modulation of insulin secretion, proliferation and cell viability in mouse pancreatic β-cells. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]