Effects of high glucose on expression of PINCH-1 inrenal interstitial fibroblasts from rats

Objective To observe the effects of high glucose on expression of particulary interesting new cysteine-histicline rich protein-1 (PINCH-1) and integrin-linked kinase (ILK) in renal interstitial fibroblasts (NRK49F) from rats, and to investigate the role and possible mechanism of PINCH-1 in the pathogenesis of diabetic kidney disease.Methods (1)NRK49F cells from rats were cultured in vitro in high glucose medium (25 mmol/L) and low glucose medium 5.5 mmol/L), respectively. After 6 hours, 12 hours, 24 hours, 48 hours and 72 hours, the changes of the mRNA and protein expression of PINCH-1, ILK and α-smooth muscle actin (α-SMA) in these groups were detected by real-time quantitative polymerase chain reaction (RT-qPCR) and immunocytochemistry (ICC). The expressions of fibronectin (FN) and collagen type I (Col I) were determined with ELISA. (2)The NRK49F cells were cultured in the media at different concentrations of glucose (5.5 mmol/L, 15.0 mmol/L, 25.0 mmol/L). After 48 hours, the mRNA and protein expression of PINCH-1, ILK and α-SMA were detected.Results (1)Compared with the low glucose group, the mRNA and protein expressions of PINCH-1, ILK and α-SMA in the high glucose group were up-regulated significantly, and exhibited a time-dependent at the early stage of high glucose stimulation. The secretion levels of Col I and FN continued to increase with the prolongation of high glucose stimulation. All the differences were of statistically significance (P<0.05). (2)After NRK49F cells were cultured in the media at different concentrations of glucose (5.5 mmol/L, 15.0 mmol/L, 25.0 mmol/L) for 48 hours, the mRNA and protein expressions of PINCH-1 and ILK increased in a concentration-dependent manner. The secretion levels of Col I and FN continued to increase with the increase of glucose concentration. Conclusions High glucose can promote the expression of the regulatory proteins PINCH-1 and ILK in NPK49F, the phenotype transformation of fibroblasts, and the secretion of fibrotic proteins Col I and FN. PINCH-1 may play an important role in the pathogenesis and progression of renal interstitial fibrosis in patients with diabetic kidney disease, through the interaction with ILK.