Nitric Oxide (NO) and Caspase-8 in Liver of Streptozotocin-Induced Diabetic Rats.

INGARAMO P. I.; RONCO M. T.; FRANCÉS D. E.; GALLEANO M; MONTI J. A.; CEBALLOS M. P.; CARRILLO M. C.; CARNOVALE C. E.

Extension Center of the Catholic University of Chile

Congreso; Free Radicals and Antioxidants in Chile 2009; 2009

SFRBM-South American Group

Introduction: Free radical production is involved in the pathogenesis of Diabetes mellitus. Aim: To study the regulation of NO production by inducible nitric oxide shynthase enzyme (NOS2) in liver of diabetic rat and the role of NO in caspase 8?induced apoptosis. Methodology: Adult male Wistar rats were randomized in 3 groups: (C) control (citrate buffer, pH=4.5), (D) diabetic (streptozotocin (SZ), 60 mg / kg of body weight (bw) ip), (D+I) diabetic with insulin (15 days post-SZ, 30 UI/kg bw, sc, three times a day during 15 days). Rats of three groups were treated with 100 mg/kg bw of aminoguanidine (AG) a day for 10 days. 30 days post-injection of SZ, rats of all groups were autopsied. Results: Glycemia (enzymatic method, g/l): C: 1.17±0.01; D:4.67±0.42*; D+I:0.85±0.01?. Bw (g): C:439±8; D:297±9*; D+I:421±13?. NO in blood (Electronic Paramagnetic Resonance (EPR), arbitrary unit (AU)): C: undetectable; D:22026±2571*; D+I: undetectable?. NO in liver total homogenate (EPR, AU). C: 49305±21384; D:199877±67838*; D+I: 37238±6460?; D+AG: 51493 ±34127?; D+I+AG: 45150±27183?. Western blot, as percentage of C: NOS2 in cytosol: D: 439.7±56.5*; D+I:238.0±66.0?, D+AG:265.3±55.4?; D+I+AG: 126.0±8.6?. Caspase-8 activity (colorimetric method, AU): C:3.8±1.8 D:57.8±2.7*; D+I:2.3±0.9?; D+AG:4.5±3.8?. *p