The anti-fibrosis effect of ghrelin in human hepatic stellate cells via PI3K-AKT pathway / 中国综合临床

ABSTRACT

Objective To observe the effect of ghrelin on the expression of procollagen type Ⅰ and alpha smooth muscle actin (α-SMA) synthesis in vitro cultured human hepatic stellate cell (HSC-LX2) stimulated by Platelet-derived growth factor-BB (PDGF-BB).Besides,the effect of PI3K-AKT pathway was studied.Methods Cultured LX2 were intervented and jointing intervented according to the different ghrelin concentration by ghrelin and PDGFcontrol group,0.1 μmol/L Ghrelin group,10 μg/L PDGF group,0.05 μmol/L Ghrelin +10 μg/L PDGF group,0.1 μmol/L Ghrelin + 10 μg/L PDGF group,0.15 μmol/L Ghrelin + 10 μg/L PDGF group.Culture HSC-LX2 in vitro,joint intervention cells with different concentrations.Procollagen Ⅰ mRNA expression were detected by Polymerase chain reaction (PCR),besides,α-SMA and AKT expression were detected by Western blot in each groups.After treatment by PI3K specific inhibitor LY294002 in LX2,three groups were divided into PDGF,Ghrelin + PDGF and LY294002 + Ghrelin +PDGF.Procollagen Ⅰ mRNA expression were detected by PCR,and α-SMA was detected by Western blot.Results PCR results showed that procollagen Ⅰ expression in PDGF treated group was significantly higher than the control group ((6.91 ± 0.46) vs.(1.00 ± 0.08),P ＜ 0.05),so PDGF can promote the expression of procollagen type Ⅰ.Procollagen Ⅰ mRNA expression between ghrelin group(0.60±0.13) and blank control group had no significant change(P＞0.05).Procollagen Ⅰ mRNA expression between different concentrations of Ghrelin and PDGF (3.11 ± 0.28,2.03 ±0.23,0.70 ± 0.06) was significantly reduced than PDGF group.The difference was statistically significant (P ＜0.05),and with the increase of the ghrelin concentration of the inhibition,the effect was more obvious in a concentration dependent manner.Western blot showed that α-SMA expression was lower in Ghrelin +PDGF group than PDGF group.AKT expression was higher in Ghrelin +PDGF group than PDGF group,indicating that PI3K-AKT may participate in the anti-fibrosis effect of ghrelin in LX2.After treatment of PI3K specific inhibitor,procollagen Ⅰ expression in LY294002+Ghrelin +PDGF group was significantly higher than Ghrelin +PDGF group((4.13±0.21) vs.(2.34±0.25),P＜0.05).Western blot also showed that α-SMA expression was higher in LY294002 + Ghrelin + PDGF group than Ghrelin + PDGF group.It was suggested that after inhibitation of PI3K,the anti-fibrosis effect of ghrelin in LX2 was attenuated.Conclusion After stimulated by PDGF in hepatic stellate cell,ghrelin can inhibit procollagen type Ⅰ and alpha-SMA synthesis in the process of hepatic fibrosis via PI3K-AKT pathway,thus,ghrelin may become one of the new ways of prevention and treatment of liver fibrosis.