EFFECT OF LIPOIC ACID ON CYCLOPHOSPHAMIDE-INDUCED DIABETES AND INSULITIS IN NONOBESE DIABETIC MICE

In an animal model of type I diabetes, the non-obese diabetic (NOD) mo use, the influence of the antioxidant lipoic acid (LA) on the developm ent of diabetes was investigated. Acceleration of diabetes development with cyclophosphamide (CY) resulted in 60% diabetic animals with seve rely infiltrated islets within 1 - 3 weeks. Daily administration of li poic acid for 20 or 30 days around cyclophosphamide treatment suppress ed the incidence of diabetes to 30% (P<0.05) and 33%, respectively. Se miquantitative analysis of islet infiltration showed a reduction of se vere intraislet infiltration and an increase in the percentage of isle ts with mild peri-insular and periductular infiltrates (from 8.4 to 29 .6 and 25.9%, respectively, P<0.01) after lipoic acid treatment. These results show that the protective effect of lipoic acid on diabetes de velopment correlates with partial suppression of islet inflammation. T he anti-inflammatory action of lipoic acid may be due to its ability t o scavenge oxygen radicals and to suppress nitric oxide production.