HO-1/EBP interaction alleviates cholesterol-induced hypoxia through the activation of the AKT and Nrf2/mTOR pathways and inhibition of carbohydrate metabolism in cardiomyocytes

Abstract

Heme oxygenase-1 (HO-1) is an inducible and cytoprotective enzyme that provides a defense against oxidant damage. The present study screened 137 HO-1/interacting proteins using a profound co-immunoprecipitation (Co-IP) coupled with proteomics, and profiled the global HO-1 interactome network, including oxidative phosphorylation, endoplasmic reticulum and transport vesicle functions. Among these molecules, we observed that a novel interactor, emopamil-binding protein (EBP), is closely related to the cholesterol metabolism process. This study demonstrated that cholesterol promotes excessive oxidative stress and alters the energy metabolism in cardiomyocytes, further triggering numerous cardiovascular diseases. We observed that cholesterol caused the overexpression of EBP and HO-1 by the activation of AKT and Nrf2/mTOR pathways. In addition, HO-1 and EBP performed a myocardial protective function. The overexpression of HO-1 alleviated the cholesterol-induced excessive oxidative stress status by inhibition of the carbohydrate metabolism. Notably, we also confirmed that the loss of partial HO-1 activity aggravated the oxidative damage and cardiac systolic function induced by a high-fat diet in HO-1 heterozygous (HO-1+/−) mice. These findings indicate that the HO-1/EBP interaction plays a protective role in alleviating the dysfunction of oxidative stress and cardiac systolic function induced by cholesterol stimulation.

Thermal cycling protects SH-SY5Y cells against hydrogen peroxide and β-amyloid-induced cell injury through stress response mechanisms involving Akt pathway

“…Cells treated with TC-HT, HT, or H 2 O 2 were harvested and lysed in RIPA lysis butter (EMD Millipore). The cells were harvested within 24 h after H 2 O 2 treatment, and the timing for different protein collections was adjusted based on previous literatures [ 18 – 20 ]. For HSP70 and HSP105, cells were lysed 16 h after H 2 O 2 treatment.…”

Oxidative Stress in Ischemic Heart Disease

“…HO-1 is a microsomal enzyme induced in oxidative stress that metabolizes heme to biliverdin, carbon monoxide (CO), and iron, and CO has antiapoptotic and anti-inflammatory properties and may act as a vasodilator in atherogenesis when NO bioavailability is reduced due to ROS inactivation [ 305 ]. Numerous studies have shown a cardioprotective effect of HO-1 [ 306 – 308 ]. Thus, it is clear that suppression of the Bach1 protein expression alters cellular redox signaling and enhances the expression of antioxidant enzymes induced by Nrf2 [ 309 ].…”

Cardiac function dependence on carbon monoxide

“… 124 In another study, down regulation of cardiac contractile proteins with resultant myocardial depression during sepsis was mitigated by CO. 125 Using proteomics, Bauer and colleagues identified the structural protein vimentin as an additional vascular endothelial growth factor-HO-1 target in vascular endothelial growth factor-mediated angiogenesis. 126 Jin et al 127 used proteomics to determine that HO-1/EBP interaction is protective in attenuating dysfunction of oxidative stress and cardiac systolic function induced by cholesterol stimulation. Heart maps detailing anatomy and cell types to determine abnormal biochemical pathways in “sick hearts” will help to define biomarkers, therapeutic targets, and disease signatures important in cardiac health.…”