The effects of glucose and insulin in culture medium on the release and cellular content of β-hexosaminidase were studied in fibroblast cultures obtained from patients with type II diabetes and from control subjects. The release of β-hexosaminidase was (positively) correlated to extracellular glucose concentration. The cellular activity was not influenced by glucose. Insulin had no effect on the cellular activity or the release of β-hexosaminidase. The results were similar for both cell types. It is proposed that increased plasma levels of lysosomal hydrolases (e.g. β-hexosaminidase) from human diabetics might be due to increased release from cells exposed to elevated glucose concentrations.
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