[Mechanism of Qijia Rougan Decoction and its disassembled formulas on regulation of VEGF/SRF/c-FOS pathway and improvement of hepatic sinusoidal capillaryization in rats with hepatic fibrosis]

This study aims to reveal the mechanism of Qijia Rougan Decoction(QJRG) and its disassembled formulas in mitigating hepatic fibrosis via the vascular endothelial growth factor(VEGF)/serum response factor(SRF)/c-FOS pathway and hepatic sinusoidal capillarization. Male Sprague-Dawley(SD) rats were randomized into a control group(n=6) and a modeling group(n=28). Hepatic fibrosis was induced by subcutaneous injection of 40% carbon tetrachloride(CCl_4) in olive oil. The successfully modeled rats were grouped as follows: model(n=7), QJRGF(n=6), disassembled formula for benefiting Qi and nourishing blood(YQYX, n=6), and disassembled formula for resolving stasis and dredging collaterals(HYTL, n=6). The rats in the YQYX, HYTL, and QJRG groups were administrated with corresponding medicines by gavage, while those in the control group and the model group were treated by gavage of normal saline. After 28 days, the rats were sacrificed, and serum and liver samples were collected. Hematoxylin-eosin staining and Masson staining were employed to observe inflammation and fibrosis, respectively, in the liver tissue. The serum levels of alanine aminotransferase(ALT) and aspartate aminotransferase(AST) were measured to assess the liver function. The expression levels of α-smooth muscle actin(α-SMA) and collagen Ⅰ in the liver tissue were measured to evaluate the activation of hepatic stellate cells(HSCs). The expression levels of vascular endothelial growth factor A(VEGFA), vascular endothelial growth factor receptor 2(VEGFR-2), SRF, c-FOS, cluster of differentiation 31(CD31), and von willebrand factor(vWF) in the liver tissue were measured. Scanning electron microscopy(SEM) was employed to observe the morphology of the fenestrae in liver sinusoidal endothelial cells(LSECs) to elucidate the mechanisms underlying the antifibrotic effects of QJRG and its disassembled formulas. Compared with the model group, QJRG, YQYX, and HYTL mitigated the pathological changes in the liver tissue, reduced the ALT and AST levels and liver index(P<0.01), and lowered the α-SMA and collagen Ⅰ levels in the liver tissue(P<0.01). QJRG, YQYX, and HYTL were capable of maintaining the fenestrae morphology of LSECs and down-regulating the protein and mRNA levels of CD31 and vWF in the liver tissue(P<0.05). Moreover, they down-regulated the protein and mRNA levels of VEGFA, SRF, and c-FOS(P<0.05) and restored the protein and mRNA level of VEGFR-2(P<0.05). QJRG outperformed its disassembled formulas(P<0.05). In summary, QJRG and its disassembled formulas can restore the liver function, mitigate pathological damage, inhibit the activation of HSCs, and alleviate hepatic fibrosis and sinusoidal capillarization by regulating the VEGF/SRF/c-FOS signaling pathway. QJRG outperforms HYTL, which suggests that the combination of nourishing and dredging has positive significance in the treatment of hepatic fibrosis and sinusoidal capillarization.