Sulfate incorporation into glycosaminoglycans of human lung fibroblasts as influenced by the number of subcultures and glycosaminoglycan polysulfate.

The influence of a glycosaminoglycan polysulfate (GAGPS) on the glycosaminoglycan (GAG) metabolism was investigated in relation to in vitro ageing of cultured human lung fibroblasts (Flow 2002). The incorporation of 35S-sulfate was determined following proteolytic digestion and specific degradation methods for the individual GAGs. In untreated cultures the pericellular matrix and medium showed a decrease of chondroitin sulfate (CS) 35S-radioactivity of the higher passage numbers, while the pericellular heparan sulfate (HS) showed increasing values. In GAGPS-treated cultures the decrease of 35S-sulfate incorporation into CS and dermatan sulfate of the cells and medium as well as into the pericellular CS was negatively correlated to the passage numbers, since GAGPS preferentially increased the radioactivity in cultures of low passage numbers. The HS values, however, were changed in the same direction as observed in untreated controls. Thus, age-related changes in the GAG metabolism become visible when exogenous GAGPS is used as a stimulus.