Long-term preservation of rat pancreatic islets under physiological conditions

In this study, we found that islet cells treated with polyphenol could be p reserved for over 2 months under physiological conditions retaining their o riginal function and maintaining their spherical shapes without any insulin secretion. When islets were treated at higher concentration than 250 mug m l(-1), these islets could retain their compact spherical shape over 65 days whereas non-treated islets were scattered ease to break within 2 weeks. Th e secretional capacity from treated islets in the initial stage is also low er than untreated islets. However, in the case of untreated islets, insulin release rapidly lowered with the progress in the culture time and secretio n completely disappeared after 9 days. On the contrary, islets treated with polyphenol (250 mug ml(-1)) in RPMI culture medium showed significant enha ncement of insulin secretion on 40th day. The secretional capacity of islet s was greatly dependent on the treating concentration. Polyphenol treatment may be a useful method for preservation of mammalian islet cells. By chang ing the concentration of polyphenol, it is possible to control the preserva tion duration and insulin secretion of islets. (C) 2001 Elsevier Science B. V. All rights reserved.