Mechanism of TRPC in promoting extracellular matrix deposition of glomerular mesangial cells / 西安交通大学学报(医学版)

ABSTRACT

【Objective】 To explore the role and mechanism of TRPC in promoting extracellular matrix (ECM) deposition in rat glomerular mesangial cells (HBZY-1). Methods Immunofluorescence staining was performed to observe the distribution and expression of TRPC1 and TRPC6 in HBZY-1 cells. After AngⅡ stimulation, qRT-PCR and Western blotting were used to detect the mRNA and protein expressions of Gαq/PLCβ4/TRPC signaling pathway main proteins and ECM deposition indicators (α-SMA, collagenⅢ and fibronectin). By silencing the expressions of TRPC1 and TRPC6 by RNA interference, the expressions of ECM deposition indicators were detected. Changes in [Ca2+]i influx were determined through Fluo-4AM Ca2+ imaging. 【Results】 Both TRPC1 and TRPC6 were expressed in HBZY-1, and were mainly located in cell membrane and cytoplasm. After AngⅡ stimulation, Gαq/PLCβ4/TRPC signaling pathway was activated, and the mRNA and protein expressions of Gαq, PLCβ4, TRPC1 and TRPC6 were all increased (P<0.05). [Ca2+]i influx also increased (P<0.01), and the mRNA and protein expressions of ECM deposition indicators (α-SMA, ColⅢ and Fn) were upregulated (P<0.05). Silencing the expressions of TRPC1 and TRPC6 by RNA interference led to decreased [Ca2+]i influx (P<0.05), and downregulated mRNA and protein expressions of ECM deposition indicators in HBZY-1 cells (P<0.05). The results suggested that inhibition of TRPC expressions could inhibit AngⅡ induced ECM deposition in HBZY-1 cells, which might be associated with decreased [Ca2+]i influx. 【Conclusion】 TRPC may be a novel therapeutic target of renal fibrosis.