Insulin status differentially affects energy transduction in cardiac mitochondria from male and female rats

Abstract

The results suggest that differential effects of STZ-diabetes and insulin treatments in the female rats than in males may be the underlying cause for increased incidence of diabetic cardiomyopathies in the females.

Diabetic cardiomyopathy and reactive oxygen species (ROS) related parameters in male and female rats: A comparative study

“…The trend was comparable for diabetic female rats, except that insulin treatments had only marginal restorative effect on body weight (Table 1). These observations are consistent with our previously reported results (31).…”

“…It is also well documented that the rates of substrate oxidation are significantly high in cardiac mitochondria (28)(29)(30)(31). This is consistent with the higher energy demand of the cardiac tissue (27,32).…”

“…Also, insulin treatment resulted in differential hyper-stimulation of respiratory activity in cardiac mitochondria from the male and female rats (28). Since the effects of diabetes and insulin treatment were differential in the male and female rats, and the incidence of CVDs is reported to be higher in the diabetic females (5,6,11,31) it was of interest to find out if the cardiac ROS metabolism is differentially affected in a sex-dependant manner. It is expected that such studies can provide insights into the underlying role of ROS in etiology of CVDs in diabetes.…”

Diabetic Modulation of the Temperature Kinetics Properties of Cytochrome Oxidase Activity in Rat Brain Mitochondria

“…We have previously shown that in the streptozotocin (STZ)-diabetic rats the rates of substrate oxidation by cerebral mitochondria decreased significantly with a parallel decrease in the contents of cytochrome aa 3 , b and c + c 1; insulin treatment was ineffective in restoring the rates of substrate oxidation although the contents of cytochromes aa 3 and c + c 1 were restored to normality [8]. Also in long-term alloxan-diabetes, treatment with insulin caused lowering of the contents of total phosholipid (TPL) and cholesterol (CHL), and the proportion of phosphatidylserine (PS) and phosphatidylinositol (PI) [11].…”

“…The content of cytochrome oxidase in mitochondria from various tissues including brain is significantly influenced by hormonal status of the organism. [6][7][8][9][10].…”