ABSTRACT
Objective To demonstrate that miR-483-5p and its targeted gene ERK1 involved in the regulation of proliferation and apoptosis of human granulosa cells.Methods ① The ERK1 mRNA and protein level expression were detected by PCR and Western blot after miR-483-5p overexpression in vitro normal human granular cells.De-tected the relative luciferase density after cotransfecting miR-483-5p mimics and its control respectively with wild or mutant ERK1 mRNA 3`UTR cloned luciferase report vector in granular cells.② Granular cells proliferation and ap-optosis were detected by MTT and TUNEL after transfecting miR-483-5p mimics or ERK1 siRNAs alone or simulta-neously.Results ① It showed that both ERK1 mRNA and protein in granular cells were markedly downregulated after the transfection of miR-483-5p mimics.A significant relative luciferase activity decrease were detected in the granular cells co-transfected with ERK1 wild and miR-483-5p mimics comparison with the control mimics,but not in the cells co-transfected with the ERK1 mutant and miR-483-5p mimics.② When miR-483-5p mimics and ERK1 siRNAs were alone or co-transfected into granular cells,the proliferation was inhibited while apoptosis trend was monitored to be promoted in all cases.No obvious statistic difference was shown between each other.Conclusion MiR-483-5p is involved in the regulation of the proliferation and apoptosis of human granulosa cells by directly binding to the target gene ERK1.
ABSTRACT
Objective To investigate the mechanism of increasing of the level of kidney injury molecule-1(KIM-1)in culture supernatant of human kidney cells(HKC)induced by cyclosporine A(CsA),and to clarify the relationships between the expression levels of KIM-1 and p38 MAPK pathway and ERK1/2MAPK pathway in HKC. Methods The HKC at logarithmic growth phase were randomly divided into control group, CsA control group, CsA + p38 kinase inhibitor group, p38 kinase inhibitor group, CsA + ERK1/2 inhibitor group and ERK1/2 kinase inhibitor group.The inhibitory rates of proliferation of HKC in various groups were detected by MTT assay, and the expression levels of KIM-1 in HKC supernatant in various groups were detected by ELISA;the survival rates,apopototic rates and necrotic rates of the HKC in various groups were detected by flow cytometry. Results Compared with control group,the expression level of KIM-1 protein in the supernatant of HKC in CsA control group was significantly increased (P0.05).Compared with CsA control group,the expression levels of KIM-1 protein in CsA+ p38 kinase inhibitor group and CsA+ ERK1/2 kinase inhibitor group were significantly decreased (P<0.05),and the survival rate was significantly increased (P<0.05),while the apoptotic rate and the necrotic rate were significantly decreased (P<0.05).Conclusion p38 MAPK pathway and ERK1/2MAPK pathway are involved in the process of up-regulation of the KIM-1 level in HKC culture supernatant induced by CsA,and the expression of KIM-1 may become the biochemical marker of clinical monitoring of CsA nephrotoxicity.
ABSTRACT
Insulin-like growth factor binding proteins (IGFBPs) are important components of insulin growth factor (IGF) signaling pathways. One of the binding proteins, IGFBP-5, enhances the actions of IGF-1, which include the enhanced proliferation of smooth muscle cells. In the present study, we examined the expression and the biological effects of IGFBP-5 in vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). The levels of IGFBP-5 mRNA and protein were found to be higher in the VSMC from SHR than in those from WKY. Treatment with recombinant IGFBP-5-stimulated VSMC proliferation in WKY to the levels observed in SHR. In the VSMCs of WKY, incubation with angiotensin (Ang) II or IGF-1 dose dependently increased IGFBP-5 protein levels. Transfection with IGFBP-5 siRNA reduced VSMC proliferation in SHR to the levels exhibited in WKY. In addition, recombinant IGFBP-5 significantly up-regulated ERK1/2 phosphorylation in the VSMCs of WKY as much as those of SHR. Concurrent treatment with the MEK1/2 inhibitors, PD98059 or U0126 completely inhibited recombinant IGFBP-5-induced VSMC proliferation in WKY, while concurrent treatment with the phosphatidylinositol-3 kinase inhibitor, LY294002, had no effect. Furthermore, knockdown with IGFBP-5 siRNA inhibited ERK1/2 phosphorylation in VSMC of SHR. These results suggest that IGFBP-5 plays a role in the regulation of VSMC proliferation via ERK1/2 MAPK signaling in hypertensive rats.