[The role of nitric oxide and superoxide synthesis in protective mechanism of ecdysterone in the heart mitochondria of rats with streptozotocin-induced diabetes].
This study evaluated generation of O2*- and NO in heart mitochondria isolated from 9-week old streptozotocin (STZ)-induced diabetic rats and the effect of ecdysterone treatment on these parameters. Mitochondria isolated from 9-week old placebo-treated rats were used as control. Several parameters were evaluated: O2*- production, the levels of stable NO metabolites nitrate, nitrite and total nitrosothiols, the level of bilirubine (as marker of CO generation), inducible (iNOS) and constitutive (nNOS) mtNOS, NADH- dependent nitrate reductase (NR) and inducible arginase II (AII) activity. We observed that diabetes was accompanied by a significant decrease in nNOS activity, nitrite, total nitrosothiols and bilirubine content while iNOS, NR and AII activity, as well as O2*- generation was increased in heart mitochondria. Ecdysterone treatment normalized the levels of stable NO metabolites, ability to generate superoxide, iNOS and nNOS activity, but not bilirubine level, NR and AII activity. These results suggest that ecdysterone treatment attenuates diabetes-induced mitochondrial alterations protecting against oxidative and nitrosative stresses. Thus, ecdysterone therapy, besides its well known importance in the maintenance of glycemic control, may help to protect against mitochondrial dysfunction associated to several age-related disorders.
Korkach
Iu P
IuP
Rudyk
O V
OV
Kotsiuruba
A V
AV
Prysiazhna
O D
OD
Sahach
V F
VF
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism* / Q000503:physiopathology; D004441:Ecdysterone / Q000494:pharmacology* / Q000502:physiology; D008929:Mitochondria, Heart / Q000187:drug effects* / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis*; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D013481:Superoxides / Q000378:metabolism*
D000975:Antioxidants; D013481:Superoxides; D009569:Nitric Oxide; D004441:Ecdysterone