壮药叶下珠醇提物通过调控NF-κB/TGF-β1/Smad信号通路改善四氯化碳诱导的大鼠肝纤维化OA

Objective To investigate the therapeutic effects of the ethanol extract of Yexiazhu(Phyllanthus urinaria)(EEPU)on carbon tetrachloride(CCl4)-induced hepatic fibrosis(HF)in rats and to explore its potential mechanism based on the nuclear factor-κB(NF-κB)/transforming growth factor-β1(TGF-β1)/Smad signaling pathway.Methods A HF model was established in SD rats by intraperitoneal injection of CCl4 olive oil solution.The successfully modeled rats were randomly assigned into model,colchicine(0.12 mg/kg),and low-,medium-,and high-dose EEPU groups(4,8,16 g/kg),with eight rats in each group,along with another normal control group.From the 9th week onwards,the modeled rats were given the corresponding drug intervention by gavage once daily for four consecutive weeks.At the end of the experiment,body weight was measured;liver and spleen indices were calculated;serum levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST),malondialdehyde(MDA),and superoxide dismutase(SOD)were determined by colorimetry;serum levels of hyaluronic acid(HA),laminin(LN),typeⅢprocollagen(PCⅢ),typeⅣcollagen(Ⅳ-C),tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-6,and transforming growth factor-β1(TGF-β1)were determined by ELISA;pathological changes in liver tissue were observed using HE,Masson,and Sirius Red staining;the expression levels of α-smooth muscle actin(α-SMA)and CollagenⅠ in liver tissue were determined by immunohistochemistry;mRNA and protein expression levels of NF-κB,TGF-β1,Smad3,and Smad7 in liver tissue were examined by RT-qPCR and Western blot.Results Compared with the normal group,the model group exhibited decreases in body weight,serum level of SOD,and mRNA and protein expression levels of Smad7(P＜0.01),as well as increases in liver and spleen indices,serum levels ofALT,AST,MDA,HA,LN,PCⅢ,Ⅳ-C,TNF-α,TGF-β1,IL-1β,and IL-6,levels of α-SMA and CollagenⅠ in liver tissue,mRNA and protein expression levels of NF-κB,TGF-β1,and Smad3 in liver tissue(P＜0.01).Compared with the model group,all drug groups showed increases in body weight,serum levels of SOD,and mRNA and protein expression levels of Smad7(P＜0.05,P＜0.01),along with decreases in liver and spleen indices,serum levels of ALT,AST,MDA,HA,LN,PCⅢ,Ⅳ-C,TNF-α,TGF-β1,IL-1β,and IL-6,levels of α-SMA and CollagenⅠ in liver tissue,as well as mRNA and protein expression levels of NF-κB,TGF-β1,and Smad3 in liver tissue(P＜0.05,P＜0.01).Compared with the colchicine group,the low-and medium-dose EEPU groups exhibited decreases in body weight and serum level of SOD(P＜0.01),along with increases in liver and spleen indices,serum levels ofALT,AST,MDA,HA,LN,PCⅢ,Ⅳ-C,TNF-α,TGF-β1,IL-1β,and IL-6,as well as expression levels of α-SMA and CollagenⅠ in liver tissue(P＜0.05,P＜0.01).Furthermore,the low-dose EEPU group showed increases in mRNA and protein expression levels of NF-κB,TGF-β1,and Smad3(P＜0.01),along with decreases in those of Smad7(P＜0.01),whereas the high-dose EEPU group showed decreases in mRNA and protein expression levels of NF-κB,TGF-β1,and Smad3(P＜0.01)and increases in those of Smad7(P＜0.01).Compared with the low-dose EEPU group,the medium-and high-dose EEPU groups demonstrated increases in body weight,serum level of SOD,and mRNA and protein expression levels of Smad7(P＜0.01),decreases in liver and spleen indices,serum levels ofALT,AST,MDA,HA,LN,PCⅢ,Ⅳ-C,TNF-α,TGF-β1,IL-1β,and IL-6,levels of α-SMA and CollagenⅠ in liver tissue,as well as mRNA and protein expression levels of NF-κB,TGF-β1,and Smad3 in liver tissue(P＜0.05,P＜0.01).Compared with the medium-dose EEPU group,the high-dose EEPU group showed increases in body weight,serum level of SOD,and mRNA and protein expression levels of Smad7(P＜0.05,P＜0.01),along with decreases in liver and spleen indices,serum levels ofALT,AST,MDA,HA,LN,PCⅢ,Ⅳ-C,TNF-α,TGF-β1,IL-1β,and IL-6,levels of α-SMA and CollagenⅠ in liver tissue,mRNA and protein expression levels of NF-κB,TGF-β1,and Smad3 in liver tissue(P＜0.05,P＜0.01).Conclusion EEPU effectively ameliorates CCl4-induced HF in rats by modulating the NF-κB/TGF-β1/Smad signaling pathway,enhancing antioxidant capacity,alleviating inflammatory response and liver damage,and inhibiting hepatic stellate cells activation and collagen deposition.