ABSTRACT
ObjectiveTo investigate the effect of Dendrobium officinale polysaccharide （DOP）on CCl4-induced hepatic fibrosis（HF）and its mechanism. MethodsA total of 56 male SD rats were randomly divided into seven groups： normal group（NG），model group（MG），colchicine group（CG， 0.1 mg/kg）， Fuzheng Huayu group（FG， 0.45 g/kg），low-dose DOP group（LDG， 0.05 g/kg），middle-dose DOP group（MDG， 0.1 g/kg）and high-dose DOP group（HDG，0.2 g/kg），with 8 rats in each group. HF rat model was established by subcutaneous injection with 40% CCl4 olive oil mixture， every 3-day for 10 weeks. At the end of the sixth week， the drug groups were treated with colchicine， Fuzheng Huayu and DOP solution by gavage respectively， once a day for 4 weeks. NG and MG groups were similarly handled with an equal amount of 0.9 % normal saline. Liver histopathology was detected using hematoxylin-eosin （HE）， Masson and Sirius red staining； blood biochemistry was tested for liver function and four indicators of HF； RT-qPCR and Western Blot were used to measure the expression of α-SMA， Col-I， E-cadherin， and ZEB1 genes and proteins in the liver tissues of rats， respectively. ResultsHE， Masson， and Sirius red staining showed that the liver tissue of MG rats had typical pathologic features of HF， and the degree of HF was alleviated in LDG， MDG， and HDG rats， respectively. Liver function test results showed that the serum AST， TBIL， and AKP levels were significantly lower in LDG， MDG， and HDG， compared with those of the MG （P < 0.05 or < 0.01）. Meanwhile， ALT levels in serum deceased remarkably except in LDG （P < 0.05 or < 0.01）. The four results of HF showed that the serum HA， LN， PC-Ⅲ， and COL-Ⅳ levels in LDG， MDG， and HDG rats were significantly decreased compared with those of the MG （P < 0.05 or < 0.01）. The relative expressions of α-SMA， COL-I， and ZEB1 genes and proteins were significantly decreased in the liver tissues of LDG， MDG， and HDG （P < 0.05 or < 0.01）， and the relative expression of E-cadherin gene and protein increased （P < 0.05 or < 0.01）. In addition， the expressions of HA， α-SMA， COL-I， ZEB1 and E-cadherin were dependent on the dose of DOP. ConclusionDOP alleviated the degree of CCl4 induced HF in rats by inhibiting the epithelial-mesenchymal transition in liver tissue.