Albumin and procollagen type I gene regulation in alcohol and viral-induced human liver disease.

Common features of chronic alcoholic liver disease are progressive hypoalbuminemia and liver fibrosis. The molecular mechanisms which account for these effects are still controversial. Therefore, in the present study we evaluated albumin and collagen gene expression in livers of alcohol abusers and patients with viral-induced liver disease. Albumin and pro-alpha 1 (I) collagen mRNA levels were determined in 30 patients who underwent diagnostic liver biopsy. Of 14 alcoholics, 7 had alcoholic hepatitis alone, while the other 7 had cirrhosis plus alcoholic hepatitis. Of 16 non-alcoholic patients with chronic viral infection, 6 had chronic active hepatitis and 10 cirrhosis plus chronic active hepatitis. Total RNA was extracted from a portion of each biopsy, hybridized with a human albumin or collagen cDNA clone and compared to 2 normal surgical specimens which served as controls. The Northern hybridization studies revealed that: despite the presence of inflammation and fibrosis, the albumin mRNA levels of alcoholics were similar to normal controls; these alcoholics had significantly higher levels of albumin mRNA than did patients with similar histological stages of disease due to viral infection; and all the categories of patients had markedly increased procollagen mRNA levels when compared to controls. Given these results it is tempting to speculate that alcohol may actually increase albumin mRNA content in man as it does in animals. Furthermore, the increased procollagen mRNA levels in fibrotic livers suggest that an increase in collagen synthesis may be a significant factor in the pathogenesis of hepatic fibrosis.