ISSN:
1432-0428
Keywords:
Keywords Euglycaemic insulin clamp
;
insulin sensitizer
;
isoxazolidinedione
;
insulin signaling
;
JTT-501
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary A newly synthesized antidiabetic agent, JTT-501 is an isoxazolidinedione rather than a thiazolidinedione. An oral dose of JTT-501 (100 mg · kg–1· day–1) given to 12-week-old male Zucker fatty rats for 7 days led to the amelioration of both hyperinsulinaemia (40 % of non-treated) and hypertriglyceridaemia (23 % of non-treated) as well as a 2.4-fold increased insulin sensitivity as determined by a euglycaemic insulin clamp. In our study, we further evaluated the acute effect of JTT-501 on both the glucose infusion rates (GIR) and insulin signalling in skeletal muscle. Male Sprague-Dawley (SD) rats aged 10 weeks were injected intravenously with JTT-501 (5 mg/kg) and then a euglycaemic insulin clamp was initiated and glucose infusion rates monitored for 150 min. We found that this treatment increased the glucose infusion rate by 33 % during the last 30 min in SD rats. After the clamp had been initiated for 30 min, the insulin-stimulated phosphatidylinositol 3-kinase (PI3-kinase) activities co-immunoprecipitated with insulin receptor substrate 1 (IRS-1) were also enhanced, resulting in increased glycogen synthase activities in the soleus muscles. Treatment with JTT-501 also enhanced the phosphorylation of insulin receptors and insulin receptor-substrate 1 rapidly as well as the phosphatidylinositol 3-kinase activities, which were stimulated by a bolus injection of insulin. Similarly, JTT-501 stimulated the glucose infusion rate by 30 % and enhanced insulin signalling in Zucker fatty rats. In conclusion, a newly developed isoxazolidinedione, JTT-501, rapidly potentiates the insulin sensitivity of skeletal muscle by enhancing insulin signalling and could be useful for the treatment of insulin-resistant diabetic subjects. [Diabetologia (1999) 42: 151–159]
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s001250051133
