Asian Continental Ancestry Group ; genetics ; Carcinoma, Hepatocellular ; genetics ; China ; Gene Frequency ; Genetic Predisposition to Disease ; Humans ; Liver Neoplasms ; genetics ; Mongolia ; Polymorphism, Single Nucleotide

Objective　To study the probability of using hepatitis D virus (HDV) ribozyme as a kind of anti-hepatitis-C-virus (HCV) gene thera-py drugs. Methods　The natural HDV genomic ribozyme′s stem Ⅳ was optimized and its substrate-binding region reconstructed, thus three recombinant HCV-specific HDV genomic ribozymes RzC1, RzC2 and RzC3 were obtained. HCV RNA 5'-noncoding region and 5'-fragment of C region (HCV RNA5'-NCR-C) were transcribed from plasmid pHCV-neo by T7 phage RNA polymerase in vitro, and radiolabelled at its 5'-end. The trans-cleaving reaction was performed by mixing the ribozymes and substrate at mol ratio 100∶1 under conditions as follows: 37℃, pH7.5, Mg2+ 20 mmol/L and deionized formamide 2.5 mol/L. Percentage of trans-cleaved products were calculated at different time points and used as the activity indicator of the three ribozymes. Results　RzC1, RzC2 trans-cleaved more substrate when the time extended, and got to 24.9%,20.3% after reac-ting for 90 minutes respectively; RzC3 was not able to trans-cleave its substrate. Conclusion　Recombinant HDV genomic ribozymes have the ability to trans-cleave HCV RNA, but the appropriate target sequence should be selected.

Isolated freshly rat islets were transferred to 24-well plates and incubated with different concentrations of glucose or resveratrol for 1 or 24 h.The results showed that resveratrol dose-dependently inhibited glucose-stimulated insulin secretion from isolated rat islets after 1 h incubation,with 10%,35%,and 80% (P<0.05 or P<0.01) decrease at the concentrations of 1,I0,and 100 μmol/L.10 μmol/L resveratrol decreased the intracellular calcium concentration by 60% (P<0.05).After incubation for 24 h,resveratrol increased palmitatesuppressed insulin secretion to 75% (P<0.01) of control.These results suggest that resveratrol acutely inhibits insulin secretion from primary pancreatic islet via regulating intracellular calcium ion concentration,and in the long run resveratrol may protect β-cells from lipotoxicity.

The effect of troglitazone on glucose-stimulated insulin secretion (GSIS) in pancreatic β-cells and its mechanism were investigated.10 μmol/L troglitazone had no effect on basal insulin secretion,but significantly decreased GSIS and stimulated AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) phosphorylations (all P<0.01).These reactions were completely reversed by AMPK inhibitor compound C,suggesting that the troglitazone acutely inhibits insulin secretion via stimulating AMPK activity in beta cells.