[Losartan inhibits high glucose-induced CTGF expression via ERK1/2 MAPK pathways in mouse mesangial cells]

To investigate the effects and mechanism of losartan on expression of CTGF induced by high glucose.

Mouse mesangial cells (MMCs) were cultured in vitro, initially, MMCs were stimulated by high glucose(25 mmol/L glucose) for 24 h, 48 h, 72 h, the phosphorylation of ERK1/2 was assessed by Western blot. Then MMCs were randomly divided into 5 groups: (1) Low glucose group (5.6 mmol/L glucose); (2)Sorbitol group (5.6 mmol/L glucose + 19.4 mmol/L sorbitol); (3) High glucose group (25 mmol/L glucose); (4) Losartan group (25 mmol/L glucose + 10(5) mol/L losartan); (5) ERK inhibitors group (25 mmol/L glucose + 25 micromol/L PD98059). After 48 hours, the phosphorylation of ERK1/2 were detected by Western blot. After 72 hours, the protein and mRNA expression level of CTGF were assessed by Western blot and real-time PCR.

High glucose induced the phosphorylation of ERK1/2 in a time-dependent manner. The protein expression of phosphor-ERK1/2 and CTGF were increased in high glucose group comparing with low glucose group(P<0.01), and reduced in losartan group and ERK inhibitors group comparing with high glucose group(P<0.05). The mRNA expression of CTGF was increased in high glucose group comparing with low glucose group(P<0.01) , and reduced in losartan group and ERK inhibitors group comparing with high glucose group(P<0.01).

Losartan can inhibit high glucose-induced CTGF expression in mouse mesangial cells, and the mechanisms maybe involve the interruption of ERK1/2 MAPK pathway.