Effects of antioxidants coenzyme Q10 and lipoic acid on interleukin-1 beta-mediated inhibition of glucose-stimulated insulin release from cultured mouse pancreatic islets.

During the development of the autoimmune disease, insulin-dependent diabetes mellitus (IDDM) islet cell death is thought to be mediated in part by oxygen and nitrogen free radicals and interleukin 1beta (IL-1beta), secreted by activated macrophages. Free radicals disrupt the homeostasis of biological systems by damaging major constituent molecules such as lipids, proteins, and DNA. Islet cells are quite susceptible to oxidative damage due to low levels of antioxidant enzymes involved in free radical consumption. If IDDM is associated with an imbalance of oxidative stresses and antioxidant responses in islet cells, then it may be possible to ameliorate disease by supplementating antioxidant defenses. In this study, the antioxidants coenzyme Q10 and lipoic acid were able to block IL-1beta-mediated inhibition of glucose-stimulated insulin secretion from islet cells at 10(-12) M and 10(-9) M, respectively.