The rate of synthesis of glycosaminoglycans and collagen by fibroblasts cultured from adult human liver biopsies

Abstract

Adult human liver biopsies were cultured from normal, alcoholic hepatitis, chronic active hepatitis, fibrosis plus alcoholic hepatitis (active cirrhosis), inactive cirrhosis, and drug hepatitis. The synthesis of collagen was estimated in cultures from 58 livers by measuring the conversion of [(14)C]proline to the [(14)C]hydroxyproline of collagen; that of glycosaminoglycans in cultures from 57 livers by the incorporation of [(3)H]acetate and (35)SO(4) into glycosaminoglycans (GAG). The synthesis of procollagen was increased only in cultures from alcoholic hepatitis, both in the pulse medium (P < 0.05) and in the chase medium (P < 0.02). The synthesis of insoluble collagen was increased in cultures from chronic (active) hepatitis (P < 0.01), fibrosis plus alcoholic hepatitis (active cirrhosis) (P < 0.001), and inactive cirrhosis (P < 0.05). Essentially all radioactive GAG was soluble in culture media. The predominant GAG were chondroitin-4 or -6-SO(4). The synthesis of GAG was increased only in cultures from fibrosis plus alcoholic hepatitis (active cirrhosis) both in the pulse medium (P < 0.01) and chase medium (P < 0.001). The data indicate that in the absence of immuno-competent cells or their secretory products, tissue cultures from livers showing biopsy evidence of active fibrosis in vivo may demonstrate increased synthesis of collagen and GAG in vitro. Increased (soluble) procollagen synthesis in cultures from alcoholic hepatitis was not associated with histologically demonstrable overt hepatic fibrosis in vivo, nor was it associated with increased GAG synthesis in vitro. No significant difference was demonstrable in collagen or GAG synthesis in paired cultures which contained either 300 mg/dl ethanol or 3.75 mg/dl methylprednisolone compared to their respective controls.