Ameliorative role of SIRT1 in peritoneal fibrosis: an in vivo and in vitro study

BACKGROUND: Peritoneal fibrosis is one of the major complications induced by peritoneal dialysis (PD). Damaged integrity and function of peritoneum caused by peritoneal fibrosis not only limits the curative efficacy of PD and but affects the prognosis of patients. However, the detailed mechanisms underlying the process remain unclear and therapeutic strategy targeting TGF‐β is deficient. Transforming growth factor‐β (TGF‐β) signaling participates in the progression of peritoneal fibrosis through enhancing mesothelial-mesenchymal transition of mesothelial cells. METHODS: The study aims to demonstrate the regulatory role of Sirtuin1 (SIRT1) to the TGF‐β signaling mediated peritoneal fibrosis. SIRT1(−/−) mice were used to establish animal model. Masson’s staining and peritoneal equilibration assay were performed to evaluate the degree of peritoneal fibrosis. QRT-PCR assays were used to estimate the RNA levels of Sirt1 and matrix genes related to peritoneal fibrosis, and their protein levels were examined by Western blot assays. RESULTS: SIRT1 significantly decreased in vivo post PD treatment. SIRT1 knockout exacerbated peritoneal fibrosis both in vivo and vitro. Overexpression of SIRT1 efficiently inhibited peritoneal fibrosis by inhibiting the peritoneal inflammation and the activation of TGF‐β signaling. CONCLUSION: SIRT1 ameliorated peritoneal fibrosis both in vivo and in vitro through inhibiting the expression of protein matrix induced by TGF‐β signaling.