To study of plasma lipoprotein cholesterol and effects of these changes on bile acids and cholesterol in bile during gallstone formation in rabbit model. This gallstone model was induced by high cholesterol diet (HCD). The rabbits were divided into five groups and there were ten animals in each group. The plasma highdensity lipoprotein cholesterol (HDL-C) and its subgroups (HDL2-C, HDL3-C), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), total cholesterol, triglyceride, phospholipid, bile acids and cholesterol of bile were investigated in different time. The results were as follow: ①As the time of feeding HCD passed by, the plasma total cholesterol, LDL-C and VLDL-C increased markedly (3-week group and 4-week group vs control group, P<0.05). Though the plasma HDL-C and its subfractions HDL2-C and HDL3-C did not change significantly, the function of HDL in transporting plasma cholesterol decreased markedly (from 80.00% to merely 3.68%); ②Cholesterol in bile increased gradually and there were significant differences when 3-week group and 4-week group comparing with control group. The concentration of GDCA and GCA in bile changed slightly (P>0.05). These results suggest that the changes of plasma lipoprotein cholesterol may affect the metabolism of cholesterol and bile acids and it may take an important role in the formation of gallstone.
The aim of the this study was to search for bacterial DNA sequences in cholesterol gallstones with negative bacterial culture by NP-PCR technique. Bacterial gene fragments were amplified in vitro from DNA which were extracted from cholesterol gallstones in gallbladder for identifying the existence of bacteria. The gallbladder gallstones of 30 patients were analysed. Bacterial DNA was found in the stones of 26 patients, indicating that most cholesterol gallstones harbor bacterial DNA.
Objective To discuss the changes of c-kit/scf mRNA and protein in guinea pig gallbladder fed on high cholesterol diet. Methods Twenty guinea pigs were divided into two equal groups of 10 each:the control group and lithogenic group. Normal diet and high cholesterol diet was given to each group respectively. The period of stone permeation was six weeks. RT-PCR and Western blot were used to determin the expressions of c-kit and scf mRNA and protein. Results RT-PCR results showed that the expressions of c-kit mRNA(t=6.985,P<0.01) and scf mRNA (t=6.028, P<0.01)decreased significantly in lithogenic group compared with the control group. Western blot results showed that the expressions of c-kit protein (t=10.256, P<0.01) and scf protein (t=9.586, P<0.01)decreased significantly in lithogenic group compared with the control group. Conclusions The expressions of c-kit/scf mRNA and protein decrease during the formation of cholesterol gallstones in guinea pigs fed on high cholesterol diet. Inhibition of c-kit/scf pathway may play a role in the formation of cholesterol gallstones.
Objective To review the mechanisms of cholesterol gallstones caused by female hormone so as to explore new treatments to prevent gallstones associated with estrogen and progesterone. Methods The literatures on gallstones related with female hormone were reviewed and the mechanisms of cholesterol gallstones were summarized. Results The cholesterol gallstones mechanisms was affected by estrogen through genomic effects,and the nucleation of cholesterol was promoted by estrogen through nongenomic,which resulted in the formation of cholesterol gallstones. And the bile empty dysfunction associated with estrogen through nongenomic effects was also the reason of cholesterol gallstone formation. The G proteins α subunit responsible for the motility of gallbladder were disrupted by progesterone through genomic effects,and the ionic channels and signal transduction were also interfered through nongenomic pathway,which impaired the contraction of gallbladder. However,the nongenomic effects might not play an important role in the gallstones formation caused by progesterone. Conclusions The mechanisms of cholesterol gallstones formation associated with female hormone are complicated,the understanding of chelesterol gallstones formation mechanisms might be helpful to prevent gallstones associated with estrogen and progesterone.
Objective To investigate the mRNA expressions of liver X receptor α (LXRα), farnesoid X receptor (FXR), steroid xenobiotic receptor (SXR) and liver receptor homolog 1 (LRH-1) gene in patients with cholesterol gallstone (CGS) disease in order to elucidate the biomolecular pathogenesis of gallstone formation. Methods Twenty-seven patients with CGS (CGS group) and 10 controls without gallstones (control group) were included in this study. Serum lipid composition (total cholesterol, triglyceride, high density lipoprotein cholesterol, apoprotein B, apoprotein A1), gallstone cholesterol concentration and biliary composition (cholesterol, bile salts, lecithin) were assayed. Biliary total lipid and cholesterol saturation index (CSI) were calculated. mRNA expressions of LRH-1, FXR, SXR and LXRα gene were determined by real-time polymorphism chain reaction. Results Serum high density lipoprotein cholesterol concentration was lower in CGS group than that in control group 〔(0.93±0.05) mmol/L vs (1.33±0.09) mmol/L, P<0.001〕 and serum apoprotein A1 was also lower in CGS group than that in control group 〔(1.19±0.05) g/L vs (1.36±0.06) g/L, P<0.05〕. There were no differences in serum total cholesterol, triglyceride and apoprotein B between two groups (Pgt;0.05). CSI was higher in CGS group than that in control group (1.17±0.02 vs 0.79±0.10), P<0.001. Biliary cholesterol was also higher in CGS group than that in control group 〔(7.96±0.39) mol% vs (5.26±0.89) mol%, P<0.01〕, while biliary total lipid was lower in CGS group than that in control group 〔(104.72±10.51) g/L vs (154.24±14.20) g/L, P<0.05〕. There were no differences in bile salts and lecithin between two groups (Pgt;0.05). Expression of LRH-1 gene was higher in CGS group than that in control group (14.18±1.80 vs 7.22±2.22), the difference was statistically significant (P<0.05). There were no differences in mRNA expressions of LXRα, FXR and SXR gene between two groups (Pgt;0.05). Conclusion CGS disease may be related to increased expression of LRH-1 gene.
Objective In order to study the mechanism of cholesterol gallstone formation through rabbit model which was induced by high cholesterol diet (HCD)Methods the activities of the high density lipoprotein receptor (HDLR) and low density lipoprotein receptor (LDLR) of hepatocytes were investigated. Results The results were as follows: The HDLR activity increased significantly after taking HCD for one week, at the same time, the LDLR activity only increased slightly. Thereafter, the activities of HDLR and LDLR all decreased markedly. As the time of animals taking HCD went on, serum total cholesterol, LDL cholesterol and hepatic cholesterol increased, but bile acids of biliary tract decreased gradually. Conclusion The results suggest that the changes of HDLR and LDLR activities of hepatocytes had no significant effect on bile cholesterol and the decreased HDLR and LDLR activities may cause the reduction some of substrate for bile acids synthesise and play an important role in the formation of gallstone.
ObjectiveTo explore the expressions of transthyretin(TTR) mRNA and its protein in tissues of human gallbladder with cholesterol gallstones, and to explore its role in the formation of cholesterol gallstones. MethodsGallbladder were got from cases of cholesterol gallstones(cholesterol gallstones group, n=25) and cases underwent liver transplantation with normal gallbladder(normal control group, n=9) respectively, who were treated in Ren Ji Hospital and Huashan Hospital. Real time PCR(RT-PCR) and Western blot method were used to determine the expressions of TTR mRNA and its protein respectively. In addition, 2 kinds of artificial model bile system were established to test nucleation time(NT) and nucleation activity, which added TTR and albumin(ALB). ResultsThe expression levels of TTR mRNA and protein in cholesterol gallstones group were 1.51±0.78 and 3.95±0.09 respectively, which were both higher than those of normal control group(P<0.05). The NT were(14.5±1.3)d and(18.0±0.8)d in TTR group and ALB group in small model bile system(P<0.01), which was similar with comprehensive model bile system[(13.5±0.6)d vs. (18.5±1.3)d]. The nucleation activity were 0.81 and 0.73 in small model bile system and comprehensive model bile system respectively. ConclusionsExpression of TTR up-regulates in human gallbladder tissues of patients with cholesterol gallstones, and TTR plays role of nucleation in model bile system, which is related to the formation of cholesterol gallstones.