[Effects of anandamide on proliferation of and pErk expression in primary hepatic stellate cells of schistosome-induced liver fibrosis mice].

Objective To investigate the potential therapeutic properties of the endogenous cannabinoid N-arachidonic acid aminoethanols (anandamide,AEA) in liver fibrosis by observing its affects on proliferation of and expression of phosphorylated-Erk (pErk) in primary hepatic stellate cells (HSCs) from a mouse model of schistosome-induced liver fibrosis.Methods The schistosome-induced liver fibrosis model was established by attaching cercaria to the skin on the ventral side of the mouse and allowing infection to occur via direct penetration.Six weeks later,the model was confirmed by pathological analysis of liver,with Masson trichrome staining showing collagen fiber deposition around the blood vessels and hematoxylin-eosin staining showing eosinophilic granuloma formation.Primary HSCs were isolated by discontinuous density gradient centrifugation,confirmed by immunofluorescence detection of double-staining for n-smooth muscle actin and desmin (95％ purity),and cultured in the presence of absence of various concentrations of AEA.Proliferative ability was evaluated by MTT assay and the expression of pErk was observed by Westem blotting.Results AEA treatment inhibited the proliferation of the primary HSCs in a concentration-dependent manner (AEA:5μmol/L,inhibition:7.68％; 10 μmol/L,11.65％; 20μmol/L,14.70％; 40μmol/L,15.07％; 60 μmol/L,18.18％;80 μmol/L,20.26％; 100 μmol/L,20.17％; 120 μmol/L,29.24％).AEA treatment increased pERK expression in both a concentration-dependent manner (AEA:20 μmol/L,average gray value:39.90 ± 4.61; 60 μmol/L,43.45 ± 0.91; 120 μrnol/L,52.91 ± 1.97; vs.negative control,allP＜ 0.05) and a time-dependent manner (time:15 min,average gray value:85.05 ± 15.80; 30 min,103.41 ± 11.89; 1 h,118.02 ± 12.24; 3 h,109.17 ± 15.69;6h,100.86 ± 10.55; 12h,71.70 ± 12.87; 24h,34.62 ± 14.85; 48 h,22.84 ± 11.73; vs.negative control,all except 48 h had P ＜ 0.05).Conclusion AEA can suppress the proliferative capacity of primary HSCs from schistosome-induced fibrotic livers through activation of the Erk signaling pathway. Key words: Liver cirrhosis;  Schistosomasis;  Cell proliferation;  Endocannabinoids;  Hepatic stellate cells;  Schistosome-induced liver fibrosis;  Phosphorylation-Erk