TY - JOUR
T1 - The PI3K/Akt pathway mediates the nongenomic cardioprotective effects of estrogen following trauma-hemorrhage
AU - Yu, Huang Ping
AU - Hsieh, Ya Ching
AU - Suzuki, Takao
AU - Choudhry, Mashkoor A.
AU - Schwacha, Martin G.
AU - Bland, Kirby I.
AU - Chaudry, Irshad H.
N1 - Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2007/6
Y1 - 2007/6
N2 - OBJECTIVE: To determine whether the nongenomic actions of E2 have any beneficial effect on cardiac function following trauma-hemorrhage and whether those effects are mediated via the PI3K/Akt pathway. SUMMARY BACKGROUND DATA: Since studies suggest that both genomic and nongenomic pathways are involved in mediating the salutary effects of 17β-estradiol (estradiol) following trauma-hemorrhage, we examined if the nongenomic effects of estradiol on cardiac function after trauma-hemorrhage involve the PI3K/Akt pathway. METHODS: Male Sprague-Dawley rats (∼300 g) underwent trauma-hemorrhage (mean blood pressure, 40 mm Hg for 90 min, then resuscitation). Estradiol conjugated to bovine serum albumin (BSA) (estradiol-BSA; 1 mg/kg estradiol) with or without estrogen receptor antagonist (ICI 182,780), PI3K inhibitor (Wortmannin), or vehicle was injected intravenously during resuscitation. At 2 hours after trauma-hemorrhage or sham operation, cardiac output, stroke volume, heart rate, mean arterial pressure, and ±dP/dt were measured. Cardiomyocyte PI3K, p-Akt, Akt protein expressions and apoptosis were also determined. One-way ANOVA and Tukey's test were used for statistical analysis. RESULTS: Cardiac output, stroke volume, and ±dP/dt decreased significantly after trauma-hemorrhage. Administration of estradiol or estradiol-BSA significantly improved these parameters of cardiac function. Although trauma-hemorrhage decreased cardiomyocyte PI3K protein expression and Akt phosphorylation (p-Akt), estradiol or estradiol-BSA treatment following trauma-hemorrhage prevented such decreases in cardiomyocyte PI3K protein expressions and p-Akt. The increase in cardiomyocyte apoptosis was also prevented in rats receiving estradiol-BSA. Co-administration of ICI 182,780 or Wortmannin abolished beneficial effects of estradiol-BSA on cardiac functions following trauma-hemorrhage. CONCLUSION: The PI3K/Akt pathway plays a critical role in mediating the nongenomic salutary effects of estradiol on cardiac function following trauma-hemorrhage.
AB - OBJECTIVE: To determine whether the nongenomic actions of E2 have any beneficial effect on cardiac function following trauma-hemorrhage and whether those effects are mediated via the PI3K/Akt pathway. SUMMARY BACKGROUND DATA: Since studies suggest that both genomic and nongenomic pathways are involved in mediating the salutary effects of 17β-estradiol (estradiol) following trauma-hemorrhage, we examined if the nongenomic effects of estradiol on cardiac function after trauma-hemorrhage involve the PI3K/Akt pathway. METHODS: Male Sprague-Dawley rats (∼300 g) underwent trauma-hemorrhage (mean blood pressure, 40 mm Hg for 90 min, then resuscitation). Estradiol conjugated to bovine serum albumin (BSA) (estradiol-BSA; 1 mg/kg estradiol) with or without estrogen receptor antagonist (ICI 182,780), PI3K inhibitor (Wortmannin), or vehicle was injected intravenously during resuscitation. At 2 hours after trauma-hemorrhage or sham operation, cardiac output, stroke volume, heart rate, mean arterial pressure, and ±dP/dt were measured. Cardiomyocyte PI3K, p-Akt, Akt protein expressions and apoptosis were also determined. One-way ANOVA and Tukey's test were used for statistical analysis. RESULTS: Cardiac output, stroke volume, and ±dP/dt decreased significantly after trauma-hemorrhage. Administration of estradiol or estradiol-BSA significantly improved these parameters of cardiac function. Although trauma-hemorrhage decreased cardiomyocyte PI3K protein expression and Akt phosphorylation (p-Akt), estradiol or estradiol-BSA treatment following trauma-hemorrhage prevented such decreases in cardiomyocyte PI3K protein expressions and p-Akt. The increase in cardiomyocyte apoptosis was also prevented in rats receiving estradiol-BSA. Co-administration of ICI 182,780 or Wortmannin abolished beneficial effects of estradiol-BSA on cardiac functions following trauma-hemorrhage. CONCLUSION: The PI3K/Akt pathway plays a critical role in mediating the nongenomic salutary effects of estradiol on cardiac function following trauma-hemorrhage.
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U2 - 10.1097/01.sla.0000254417.15591.88
DO - 10.1097/01.sla.0000254417.15591.88
M3 - Article
C2 - 17522524
AN - SCOPUS:34249336070
VL - 245
SP - 971
EP - 977
JO - Annals of Surgery
JF - Annals of Surgery
SN - 0003-4932
IS - 6
ER -