Effects of 17 beta-estradiol on cardiac Na+/K+-ATPase in high fat diet fed rats
AuthorsObradović, Milan M.
Mousa, Shaker A.
Isenović, Esma R.
MetadataShow full item record
The aim of this study was to investigate in vivo effects of estradiol on Na+/K+-ATPase activity/expression in high fat (HF) diet fed rats. Adult male Wistar rats were fed normally (Control, n = 7) or with a HF diet (Obese, n = 14) for 10 weeks. After 10 weeks, half of the obese rats were treated with estradiol (Obese + Estradiol, n = 7, 40 mu g/kg, i.p.) as a bolus injection and 24 h after treatment all the rats were sacrificed. Estradiol in vivo in obese rats in comparison with obese non-treated rats led to a statistically significant increase in concentration of serum Na+ (p LT 0.05), Na+/K+-ATPase activity (p LT 0.01), expression of alpha 1 (p LT 0.01) and alpha 2 (p LT 0.05) subunit of Na+/K+-ATPase, both PI3K subunits p85 (p LT 0.01), p110 (p LT 0.05), and association of IRS-1 with p85 (p LT 0.05), while significantly decrease expression of AT1 (p LT 0.05) and Rho A (p LT 0.01) proteins. Our results suggest that estradiol in vivo in pathophysiological conditions, such as obesity a...ccompanied with insulin resistance stimulates activity and expression of Na+/K+-ATPase by a mechanism that involves the participation of IRS-1/PI3K/Akt signaling. In addition, the decreasing level of AT1 and Rho A proteins estradiol probably attenuates the detrimental effect of obesity to decreased IRS-1/P13K association and consequently reduce Na+/K+-ATPase activity/expression. (C) 2015 Elsevier Ireland Ltd. All rights reserved.