Effect of DaChaiHu Decoction on pancreatic fibrosis induced by DBTC combined with alcohol and the mechanism of TGF-beta/Smad signaling pathway

Abstract

To investigate the effects of transforming growth factor-β (TGF-β) and Smad in chronic pancreatitis (CP) induced by dibutyltin dichloride (DBTC) combined with ethanol, and the effect for prevention and treatment of pancreatic fibrosis by DaChaiHu Decoction (tradeiional Chinese medicine). Ninety-six healthy male Kunming mice were randomly divided into control group (Con group), chronic pancreatitis (CP group) group, Dachai Hu decoction treatment group (DCHD group) (n=32). Then the mice were treated with DBTC 8 mg/kg by tail vein injection and fed with 10% ethanol replacing the normal drinking water to replicate mouse CP model. After three days of modeling the mice were randomly divided into CP group and DCHD group. The mice in DCHD group were administered intragastrically with DaChaiHu Decoction (1 g/ml, 6 g/kg·d) at the following 8 weeks. After modeling for 1 week, 2 weeks, 4 weeks and 8 weeks, the mice were anesthetized and sacrificed(n=8). The morphology and the degree of fibrosischanges of pancreatic tissue were detected by HE staining. The protein expressions of type I collagen and TGF beta R I, p-Smad 2/3 and Smad 7 in pancreatic tissue were detected by Western blot assay. The expressions of MMP-1/TIMP-1 mRNA inpancreatic tissue were detected by RT-PCR. Compared with control group, DBTC combined with ethanol induced CP with increased activity of serum amylase and hyaluronic acid level. While in DCHD group, the activity of amylase and hyaluronic acid level were decreased significantly. Compared with control group, the protein expressions of COLA1, TGF beta R I, p-Smad 2/3 in CP Group were elevated,but the expression of Smad 7 was significantly reduced; In DCHD treatment group,the expression of TGF beta R I, p-Smad 2/3 and COLA1 were reduced, and the protein expression of Smad 7 was increased. In 2w and 4w, the level of MMP-1mRNA continued to decrease, while TIMP-1mRNA expression was increased significantly (P<0.01). At each time point of DCHD group, the expression of MMP-1 were markedly increased and TIMP-1 were reduced, compared with those of the CP group (P<0.05). DaChaiHu Decoction play a role in the prevention and treatment of chronic pancreatitis and the development of fibrosis, the mechanism may related to inhibit the activation of TGF beta/Smad signaling pathway, and regulate the balance between synthesis and degradation of extracellular matrix.