Association of Helicobacter pylori infection with hepatic encephalopathy risk: a systematic review.

BACKGROUND: The role of Helicobacter pylori (H. pylori) in the pathogenesis of hepatic encephalopathy (HE) is still under debate. We reviewed the available evidence for a pathogenic role of H. pylori infection in determining HE in cirrhotic patients. METHODS: We searched PubMed, EMBASE, and Cochrane Library prior to 2012 for studies that explored the role of H. pylori in HE pathogenesis. RESULTS: Twenty studies were eligible for our analysis. Eleven studies investigated the epidemiology of H. pylori infection; there is evidence suggesting that the prevalence of H. pylori is higher in older HE patients. The evidence of nine studies failed to find that blood ammonia level was higher in H. pylori positive cirrhotic patients than in negative patients. Four studies suggested that gastric ammonia level was higher in H. pylori positive than H. pylori negative patients. Eleven studies investigated the effect of H. pylori eradication on the change of blood ammonia levels and the HE improvement. No new reliable evidence was found to support the effect of H. pylori eradication in reducing blood ammonia levels and improving HE symptoms. CONCLUSIONS: Current evidence confirmed the higher prevalence of H. pylori infection in HE patients. However, no new evidence supported the effect of H. pylori on the increased of blood ammonia level, nor the efficacy of H. pylori eradication in decreasing of blood ammonia level and improving HE.

[Observation of the promotion effect taurine on hepatic stellate cell's apoptosis in rat hepatic fibrosis model].

OBJECTIVE: To observe the effect of taurine on hepatic stellate cell's apoptosis induced by carbon tetrachloride (CCl4) in rats and to study its protective mechanisms. METHODS: CCl4-induced rat hepatic fibrosis was treated by taurine. Serum alanine aminotransferase (ALT), plasma protein, hyaluronic acid (HA), procollagen III (PC III), hepatic microsomal drug-metabolizing enzyme and anti-transforming growth factor beta1 (TGF-beta1) were determined. In addition, hepatic stellate cell's apoptosis and the pathological changes of liver tissue were observed under light microscope. RESULTS: The activity of serum ALT and the levels of serum HA, PC III were markedly reduced by taurine treatment. The hepatic cytochrome P450 (Cyt. P450) and cytochrome b5 (Cytb5) contents were increased by the same treatment. In addition, taurine could significantly inhibit the expression of TGF-beta1, promote the hepatic stellate cell's apoptosis, and relieve hepatic fibrosis. CONCLUSION: Taurine fulfills a role in promoting hepatic stellate cell's apoptosis in the case of hepatic fibrosis, it mitigates the liver injury, decreases the expression of TGF-beta1, and relieves hepatic fibrosis.