Abstract:

[Abstract] Objective To investigate the effect and mechanisms of prostaglandin E2 receptor subtype 1 (EP1) on transforming growth factor -β1 (TGF-β1) -induced mouse mesangial cells (MCs). Methodology: The primary MCs were generated. Three siRNAs were designed and synthesized. One of them that was capable of silencing EP1 most effectively in MCs. They were divided into five cell groups: 1)control group ;2) TGF-β1 (10 ng / ml) group ; 3) NC-siRNA + TGF-β1 (10 ng / ml) group ; 4) EP1-siRNA + TGF-β1 (10 ng / ml) group ; 5) EP1-siRNA group . The expression of PGE2 in cell supernatant of each group was detected by using ELISA, the mRNA expression of fibronectin (FN), connective tissue growth factor (CTGF), cyclooxygenase- 2 (COX2), and mPGES-1of each group was determined by using Real-Time PCR, and the proteins of FN, CTGF, COX2, mPGES-1 and the variation of phosphorylation proteins relating to MAPKs signaling pathway, such as p38, ERK, were examined by using Western blot. Results Compared with normal control group, mRNA and protein expressions of FN, CTGF, COX-2 and mPGES-1 were up-regulated in group 2 (TGF-β1 group) (P <0.05). Compared with group 2 (TGF-β1 group ) , the expressions of FN, CTGF, COX-2 and mPGES-1 mRNA and proteins were down-regulated in group 4 (EP1-siRNA + TGF-β1 group）(P <0.05). The silencing EP1 also declined TGF-β1-induced p38 and ERK phosphorylation (P <0.05). Conclusion EP1-siRNA may mitigate the damage of TGF-β1 induced MCs by inhabiting p38 and ERK1/2 phosphorylation.

Key words: prostaglandin E2 receptor subtype 1, siRNA, transforming growth factor β1, mesangial cells, signaling pathway