Intestinal mucosal proliferation, apoptosis and oxidative stress in patients with liver cirrhosis

Intestinal mucosal barrier dysfunction in liver cirrhosis and its implicated mechanisms is of great clinical importance because it is associated with the development of serious complications from diverse organs through promotion of systemic endotoxemia.

The present study was designed to investigate whether enterocytes' proliferation, apoptosis and intestinal oxidative stress are altered in the intestinal mucosa of patients with compensated and decompensated liver cirrhosis.

Twelve healthy controls (group A) and twenty four cirrhotic patients at a compensated (n = 12, group B) or decompensated condition (n = 12, group C) were subjected to duodenal biopsy. In intestinal specimens mucosal apoptotic and mitotic activity and their ratio were recorded by means of morphological assessment and mucosal lipid hydroperoxides were measured. Plasma endotoxin concentration, an index of gut barrier function, was also determined.

Cirrhotic patients presented significantly higher serum endotoxin concentrations as compared to healthy controls (P < 0.001), whilst endotoxemia was higher in decompensated disease (P < 0.05 vs. compensated cirrhosis). Intestinal mucosal mitotic count was significantly lower in patients with compensated and decompensated cirrhosis compared to controls (P < 0.01, respectively), whilst a trend towards increased apoptosis was recorded. The mitotic/apoptotic ratio was significantly reduced in groups B (P < 0.05) and C (P < 0.01) as compared to controls. Intestinal lipid peroxidation was significantly increased in decompensated cirrhotics (P < 0.001 vs. groups A and B).

The present study demonstrates for the first time that human liver cirrhosis is associated with decreased intestinal mucosal proliferation and proliferation/apoptosis ratio even at early stages of cirrhosis and increased intestinal oxidative stress in advanced liver disease.