Comparison of the gut microbe profiles and numbers between patients with liver cirrhosis and healthy individuals.

Human liver was closely associated with gut through various biological mechanisms, such as bacterium-gut interactions. Alterations of gut microbiota seemed to play an important role in induction and promotion of liver damage progression. The aim of this study was to characterize the gut microbiota in liver cirrhosis patients and assess whether there are alterations in the diversity and similarity of intestinal flora in cirrhotic patients when compared with healthy individuals. PCR-denaturing gradient gel electrophoresis (DGGE) with universal primers targeting V3 region of the 16S rRNA gene was employed to characterize the overall intestinal microbiota composition, and some excised gel bands were cloned for sequencing. Real-time PCR was further utilized to quantitatively analyze the subpopulation of microbiota using group-specific primers targeting the Enterobacteriaceae, Enterococcus and Bifidobacterium genus. The DGGE profiles of two groups demonstrated significant differences between cirrhotic and healthy groups (P < 0.05). While real-time PCR revealed significant increase of Enterobacteriaceae and Enterococcus (P < 0.05) in the cirrhotic group compared with the healthy group. The ratio of Bifidobacterium genus and Enterobacteriaceae decreased in the cirrhotic patients group, but no statistical significance. This study revealed strong relationship between alterations of gut microbiota and liver cirrhosis.