ABSTRACT
AIM:To explore the effects of galectin-3 (GAL-3) on the viability, migration and inflammation of human umbilical vein endothelial cells (HUVECs) and the mechanisms.METHODS:The HUVECs were cultured in vitro and treated with GAL-3 recombinant protein at 2 mg/L or GAL-3 short hairpin RNA (shRNA).The HUVECs were divided into normal group, recombinant GAL-3 group, shControl group and GAL-3-shRNA group.The mRNA expression of GAL-3, monocyte chemotactic protein (MCP)-1, IL-6, matrix metalloproteinase (MMP)-9 and cyclin D1 was detected by real-time quantitative PCR,and the protein expression of GAL-3, IL-6 and MCP-1 was detected by Western blot.The secretion levels of MCP-1 and IL-6 in the culture medium were measured by ELISA.The viability and the ability of migration of the HUVECs were examined by CCK-8 assay and wound healing assay.The protein levels of heat shock protein 90 (HSP90), ERK1/2, p-ERK1/2, JNK and p-JNK were determined by Western blot.RESULTS:The expression of GAL-3, MCP-1 and IL-6 at mRNA and protein levels, the mRNA expression of MMP-9 and cyclin D1, and the secretion levels of MCP-1 and IL-6 in the culture medium were significantly higher than those in normal group (P<0.05) after the HUVECs were treated with GAL-3 recombinant protein.However, these molecules mentioned above in GAL-3-shRNA group were significantly lower than those in normal group and negative control group (P<0.05).Compared with normal group, the viability and migration ability of the HUVECs in recombinant GAL-3 group were significantly increased, but the viability and migration ability of the HUVECs in GAL-3-shRNA group were lower than those in normal group and shControl group (P<0.05).In addition, the protein levels of p-ERK1/2 and HSP90 in recombinant GAL-3 group were higher than those in normal group (P<0.05), but those in GAL-3-shRNA group were lower than those in normal group and shControl group (P<0.05).The protein level of p-JNK was not oviously changed among the 4 groups.CONCLUSION:GAL-3 is involved in regulating the cell growth, migration and the release of inflammatory cytokines in vascular endothelial cells, which may be mediated by HSP90-ERK1/2 signaling pathway.
ABSTRACT
Objective: To explore the protective roll of ifbroblast growth factor 21 (FGF21) in endoplasmic reticulum stress (ERS) induced rat's H9c2 cardiomyocyte apoptosis with its mechanism. Methods: pcDNA4 was used as gene vector, pcDNA4-FGF21 plasmid was constructed and transfected into rat's H9c2 myocardiocytes for 48 h. ERS model was established by 10 μM tunicamycin (TM) induction for 24 h. The experiment was conducted in 4 groups:①Control group,②TM group, the cells were treated by TM,③pcDNA4-FGF21+TM group,④pcDNA4+TM group. The expressions of FGF21, protein kinase R-like ER kinase (PERK) and c-Jun N-terminal kinases (JNK) mediated apoptosis pathway related protein were measured by Western blot analysis; cell survival rate was examined by CCK-8 method and apoptosis rate was detected by TUNEL technique. Results: pcDNA4-FGF21 vector was successfully constructed and overexpressed in H9c2 myocardiocytes. Compared with Control group, TM group and pcDNA4+TM group had up-regulated endogenous FGF21 expression, increased PERK and JNK mediated apoptosis pathway related protein expression; reduced cell survival rate and elevated apoptosis rate. Compared with TM group and pcDNA4+TM group, pcDNA4-FGF21+TM group had down-regulated PERK and JNK mediated apoptosis pathway related protein expression; increased cell survival rate and decreased apoptosis rate. Conclusion: FGF21 overexpression can reduce ERS induced apoptosis rat's H9c2 myocardiocytes which might be partly related for inhibiting PERK and JNK mediated signal transduction of apoptosis pathway.
ABSTRACT
Objective To observe the expression and localization of D J-1 in renal fibrosis, and to investigate the expressions of E-cadherin, vimentin and the level of β-catenin tyrosine phosphorylation in human tubular epithelial cells. Methods In vitro, the human tubular epithehal cells (HKC cell line) were cultured with 10 μg/L TGF-β1 for 72 h. The protein expressions of E-cadherin, vimentin and DJ-1 were measured by Western blot. RT-PCR was used to detect the expression of D J-1 mRNA. The intracellular distribution of DJ-1 was observed by confocal microscope. In vivo, Masson stain was used to evaluate the level of renal fibrosis. The expression and disposition of DJ-1 in renal tissue were detected by immunohistochemistry. HKC cells were transfected with pEGFP-N1-DJ-1 via lipofectamine 2000. The efficiency of transfection was detected by fluorescence microscope. The expressions of DJ-1, E-cadherin, vimentin and β-catenin tyrosine phosphorylation level in the transfected cells were detected by Western blot. Results The expressions of DJ-1 protein and DJ-1 mRNA were up-regulated in renal tubular EMT cells. Most of DJ-1 protein localized in cytoplasm, and some was in nucleus. After stimulation by TGF-β1, the expressions of DJ-1 protein both in cytoplasm and nucleus was greatly increased, especially in nucleus. In vivo, renal tissue expressed DJ-1 in tubular epithelia, but little expression in glomeruli. In renal tissue from 5/6-nephrectomized rots, DJ-1 expression was greatly increased. In the DJ-1 transfectants, the expressions of DJ-1, vimentin and β-catenin tyrosine phosphorylation level were up-regulated, but E-cadherin expression was suppressed. Conclusion The increased expression of DJ-1 may promote renal fibrosis.