The expression of osteopontin and its nucleating role in gallbladder bile of patients with cholesterol gallstone / 中华肝胆外科杂志

ABSTRACT

Objective To investigate the role of osteopontin (OPN) in cholesterol gallstone formation.MethodsGallbladder bile was obtained from patients with cholelithiasis (n=36,the experimental group) and from donors of liver transplantation (n=19,the control group).OPN,calcium ion and lipid were analysed quantitively.The nucleating role of OPN in bile was evaluated using nucleating time (NT) approach.ResultsOPN inhibited cholesterol nucleation in a dose dependent manner.OPN (50 μg/ml and 100 μg/ml) prolonged NT by 48.90％ (91.51％) and 17.07％ (32.93％) in lithogenic and control bile,respectively.OPN (100 μg/ml) also inhibited the nucleating effect induced by calcium ion.Furthermore,a combination of OPN (50 μg/ml) and calcium prolonged NT by 75.78％ and 33.96％ in lithogenic and control bile,respectively.A combination of OPN (100 μg/ml) and calcium prolonged NT by 125.9％ and 62.26％ in the 2 groups.The contents of osteopontin and calcium were significantly lower in lithogenic bile than control bile (P＜0.05).On the other hand,the cholesterol saturation index and the contents of cholesterol,phospholipid and bile acid were significantly higher (P＜0.05).ConclusionsOPN inhibited cholesterol gallstone formation.It may be involved in the pathogenesis of cholelithiasis.