Cardioprotection carried out by oral administration of stevioside: the involvement of protein kinase B (Akt)

MESTRE CORDERO, VICTORIA; MOURGLIA, JULIETA; VELEZ, DEBORA; HERMANN, ROMINA; HARRIET, SOFIA; MARINA PRENDES, MARIA GABRIELA

Mendoza

Simposio; II Simposio Internacional de Medicina Traslacional; 2019

Facultad de Ciencias Médicas, Universidad de Cuyo.

Backgroundand aims: In previousstudies carried out in our laboratory, we demonstrated that oral administrationof Stevioside (E), a major component of Steviarebaudiana bertoni leaves, improved the recovery of contractile activity inhearts subjected to ischemia-reperfusion (I-R) and decreased the infarct size.These effects were, at least in part, reverted by the administration ofWortmannin (W), an upstream inhibitor of Akt. The aim of the present study wasto investigate the mitochondrial morphology and the rate of ATP synthesis afteroral administration of E (168 mg/kg for 15 days) and its relation with the activationprofile of Akt and GSK3β, inLangendorff perfused rat hearts subjected to I-R. Methods: Hearts from female Wistar rats (200-250g) fed ad libitumwere used. W (100nM) was added 15 min before I. Mitochondrial ultrastructurewas analyzed by electron microscopy, the measurement of mitochondrial ATPsynthesis was made by the luciferin-luciferase method and the activationprofile of Akt and GSK3b were studied by western blot considering Akt-P/Akt-T and GSK3b-P/GSK3b-T, respectively. ANOVA, n=8/group.Results: At the end of reperfusion, results showedan increase in mitochondrial ATP synthesis rate of hearts treated with E thatwas partly canceled by the administration of W (C: 66.3±6.5, W: 59.5±6.1, E:87.3±3.7*, E+W: 64.6±6.9 nmol/min/mg mitochondrial  protein; *p