ABSTRACT
OBJECTIVE: Cardiac fibroblasts (CFs) proliferation and extracellular matrix deposition are important features of cardiac fibrosis. Various studies have indicated that vitamin D displays an anti-fibrotic property in chronic heart diseases. This study explored the role of vitamin D in the growth of CFs via an integrin signaling pathway. METHODS: MTT and 5-ethynyl-2'-deoxyuridine assays were performed to determine cell viability. Western blotting was performed to detect the expression of proliferating cell nuclear antigen (PCNA) and integrin signaling pathway. The fibronectin was observed by ELISA. Immunohistochemical staining was employed to evaluate the expression of integrin ß3. RESULTS: The PCNA expression in the CFs was enhanced after isoproterenol (ISO) stimulation accompanied by an elevated expression of integrin beta-3 (ß3). The blockade of the integrin ß3 with a specific integrin ß3 antibody reduced the PCNA expression induced by the ISO. Decreasing the integrin ß3 by siRNA reduced the ISO-triggered phosphorylation of FAK and Akt. Both the FAK inhibitor and Akt inhibitor suppressed the PCNA expression induced by the ISO in the CFs. Calcitriol (CAL), an active form of vitamin D, attenuated the ISO-induced CFs proliferation by downregulating the integrin ß3 expression, and phosphorylation of FAK and Akt. Moreover, CAL reduced the increased levels of fibronectin and hydroxyproline in the CFs culture medium triggered by the ISO. The administration of calcitriol decreased the integrin ß3 expression in the ISO-induced myocardial injury model. CONCLUSION: These findings revealed a novel role for CAL in suppressing the CFs growth by the downregulation of the integrin ß3/FAK/Akt pathway.
Subject(s)
Calcitriol , Humans , Calcitriol/metabolism , Calcitriol/pharmacology , Fibronectins/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Isoproterenol , Proliferating Cell Nuclear Antigen/metabolism , Integrin beta3/genetics , Integrin beta3/metabolism , Vitamins , Cell Proliferation , Fibroblasts/metabolismABSTRACT
OBJECTIVE: To investigate podocyte injury and the expression of nephrin and VEGF in rat nephrosis model induced by adriamycin. METHODS: The rat adriamycin induced nephrosis model was established, while the biochemical indicators in blood and urine were measured and the pathological changes of the renal tissue were evaluated by light microscope and electron microscope. The podocyte number was counted, and the expression levels of nephrin, VEGF were examined at different time by means of immunohistochemistry. RESULTS: After second injected with adriamycin,the model group nephrin presented a weak signal in the end of the first week (P < 0.05), and the expression of VEGF started to increase at the end of the eighth week (P < 0.05). The podocyte number decreased at the end of the eighth week (P < 0.05). The expression of nephrin and the number of podocyte were negatively correlated with the 24-hour urine protein, blood urea nitrogen and serum creatinine; while the expression of VEGF was positively correlated with the 24-hour urine protein, blood urea nitrogen and serum creatinine. CONCLUSION: The decrease of nephrin expression and the change of its distribution might be the significant factors resulting in considerable proteinuria. VEGF participated in the process of proteinuria and glomerular sclerosis in the development of rat adriamycin nephrosis.
Subject(s)
Membrane Proteins/metabolism , Nephrosis/metabolism , Nephrosis/pathology , Podocytes/ultrastructure , Vascular Endothelial Growth Factor A/metabolism , Animals , Doxorubicin , Male , Membrane Proteins/genetics , Nephrosis/chemically induced , Podocytes/pathology , Random Allocation , Rats , Rats, Sprague-Dawley , Vascular Endothelial Growth Factor A/geneticsABSTRACT
OBJECTIVES: To investigate the localization and positive percentage of progesterone receptor (PR) on the human sperm surface. METHODS: After in vitro capacitation, progesterone binding sites on the sperm were quantitatively analyzed by fluorescence microscopy and flow cytometry using fluorescein isothiocyanate-labeled bovine serum albumin-progesterone complex (P-BSA-FITC). RESULTS: The spermatozoa stained by P-BSA-FITC mainly showed two labeling patterns, with the green fluorescence on the whole acrosomal region or the equatorial acrosomal region only and the stainless postacrosomal and tail regions. The percentage of progesterone-binding sperm was (30.2 +/- 2.4)%. CONCLUSIONS: There is selective expression of PR on the human sperm acrosome surface.