Takeshi Fujita

Effects of 5-[4-(1-methylcyclohexylmethoxy)benzyl]-thiazolidine-2,4-dione (ADD-3878, U-63,287, Ciglitazone) on glucose and lipid metabolism were examined in various animal models. ADD-3878, administered as a dietary admixture (30–186 mg/kg/day) to obese-diabetic yellow KK (KK-Ay) mice, markedly suppressed the diabetic syndromes (hyperglycemie, hypertriglyceride-mia, and hyperinsulinemia), accompanied by the reduction of insulin resistance as manifested by improvement of overall insulin sensitivity in either the insulin tolerance test òr the steady-state blood glucose test. Chronic administration of ADD-3878 for as long as 12 wk to young yellow KK mice, which were in the early stage of diabetes and obesity, depressed age-dependent rises in blood glucose, plasma triglyceride, and insulin without exerting any effect on obesity. When orally administered to obese Zucker-fatty rats, ADD-3878 decreased plasma insulin and triglyceride in a dose-dependent manner (5–100 mg/kg/day). The treated rats showed increased tolerance and decreased insulin secretion in response to oral glucose. The glycemie response to insulin and the steady-state plasma glucose were also normalized in the treated rats. Chronic administration of ADD-3878 to young fatty rats for as long as 12 wk decreased the dose-dependent rises in blood glucose, plasma triglyceride, and insulin without exerting any effect on body weight. ADD-3878 had no effect on glucose and lipid metabolism of young Sprague-Dawley rats and mild strepto-zotocin-diabetic rats. However, in old Sprague-Dawley rats that were moderately insulin resistant and hyperli-pidemic compared with young ones, ADD-3878 decreased plasma triglyceride and insulin and improved insulin sensitivity. Five-day administration of ADD-3878 to beagle dogs with slightly impaired glucose tolerance increased glucose tolerance and suppressed postprandial rises in plasma glucose, insulin, and triglyceride. Based on these results, ADD-3878 is effective on abnormal glucose and lipid metabolism associated with insulin resistance or obesity through reduction of peripheral insulin resistance. Therefore, ADD-3878 is expected to be useful in the treatment of hyperglycemie, hyperinsulinemia, and hyperlipemia in obese type II diabetes and Obesity.

More than 100 5-substituted thiazolidine-2, 4-diones were prepared and their hypoglycemic and hypolipidemic activities were evaluated with genetically obese and diabetic mice, yellow KK. The structure-activity relationship study showed that the 5-(4-oxybenzyl) moiety is essential for substantial activity. Among these compounds, 5-(4-cyclohexylmethoxy) benzylthiazolidine-2, 4-dione (47), 5-[4-(1-methylcyclohexylmethoxy) benzyl]-thiazolidine-2, 4-dione (49, ADD-3878) and 5-{4-[2-(3-pyridyl) ethoxy] benzyl} thiazolidine-2, 4-dione (59) exhibited the most favorable properties in terms of activity and toxicity.