Objective: To study the effect of fasudil on inhibiting the Rho/ROCK signaling pathway under high glucose in human mesangial cells (HMCs) inflammation and fibrosis.
Methods: Synchronized HMCs were divided into following groups: (1) Normal glucose control group (NG, 5.5 mmol/L glucose); (2) High glucose group (HG, 30 mmol/L glucose); (3) Mannitol group (Man, 5.5 mmol/L glucose + 24.5 mmol/L mannitol); (4) High glucose + fasudil group (HG + F, the concentrations of fasudil were 25, 50 and 100 µmol/L, respectively). Collect the supernatant and cells at 0, 12, 24, 36, 48 and 72 h respectively, and determine the concentration changes of the RhoA, ROCK-I, connective tissue growth factor (CTGF)mRNA with real-time PCR method in the cells, then used the ELISA method to check the protein content of the fibronectin (FN), CTGF, TNFα in the supernatant.
Results: (1) RhoA, ROCK-I and CTGF mRNA of the HMCs cultured under the high glucose expressed significantly higher than those in the normal group, and there was certain time-dependence. Besides, there was no statistic significance by comparing Man and NG. (2)Under the high glucose situation, after the fasudil pretreatment with different concentrations and 24 h or 48 h culture with high glucose, RhoA, ROCK-I, CTGF mRNA expression was significantly decreased in HG + F, compared with HG, and there was certain concentration-dependence. (3) High glucose increased the FN, CTGF, TNFα protein secretion of HMCs in a time-dependent manner, but normal glucose and mannitol had no such effect. (4) After the fasudil pretreatment with different concentrations and culture with high glucose for 12, 24, 36, 48, 72 h, the FN, CTGF, TNFα protein secretion was significantly reduced compared with HG.
Conclusion: Fasudil can reduce the secretion of downstream inflammatory factors and cytokines by inhibiting high glucose-activated HMCs Rho/ROCK signaling pathway, and reduce the inflammation and fibrosis of HMCs. This provides a new basis for the therapeutic target in the treatment of diabetic nephropathy.