Mechanism for resveratrol-induced cardioprotection against reperfusion injury involves glycogen synthase kinase 3β and mitochondrial permeability transition pore

Abstract

Resveratrol pretreatment can protect the heart by inducing pharmacological preconditioning. Whether resveratrol protects the heart when applied at reperfusion remains unknown. We examined the effect of resveratrol on myocardial infarct size when given at reperfusion and investigated the mechanism underlying the effect. Isolated rat hearts were subjected to 30 min ischemia followed by 2 h of reperfusion, and myocardial samples were collected from the risk zone for Western blot analysis. Mitochondrial swelling was spectrophotometrically measured as a decrease in absorbance at 520 nm (A520). Resveratrol reduced infarct size and prevented cardiac mitochondrial swelling. Resveratrol enhanced GSK-3β phosphorylation upon reperfusion, an effect that was mediated by the cyclic guanosine monophosphate (cGMP)/protein kinase G (PKG) pathway. Resveratrol translocated GSK-3β from cytosol to mitochondria via the cGMP/PKG pathway. Further studies showed that mitochondrial GSK-3β was co-immunoprecipitated with cyclophilin D but not with VDAC (voltage dependent anion channel) or ANT (adenine nucleotide translocator). These data suggest that resveratrol prevents myocardial reperfusion injury presumably by targeting the mPTP through translocation of GSK-3β from cytosol to mitochondria. Translocated GSK-3β may ultimately interact with cyclophilin D to modulate the mPTP opening.

O-Linked β-N-acetylglucosamine (O-GlcNAc) Regulates Stress-induced Heat Shock Protein Expression in a GSK-3β-dependent Manner

“…In addition to reducing heat shock protein expression through inactivation of HSF1 (discussed in this study), GSK-3␤ promotes the intrinsic pathway of apoptosis through numerous mechanisms: 1) GSK-3␤ binds to and promotes the acetylation of p53, which in turn activates proapoptotic changes in gene expression (104); 2) phosphorylation of myeloid cell leukemia sequence-1 by GSK-3␤ induces ubiquitination and subsequent degradation of this anti-apoptotic BCL-2 protein; 3) GSK-3␤ phosphorylates and inactivates the translation initiation factor eIF2B; 4) GSK-3␤ phosphorylates Bax at Ser 163 , promoting mitochondiral localization; 5) GSK-3␤ is required for the stressinduced expression of BIM; and 6) GSK-3␤ promotes collapse of mitochondrial membrane potential through opening of the mitochondrial permeability transition pore (56, 79, 104 -107). The latter appears to be regulated by a number of events including direct phosphorylation by GSK-3␤ of VDAC, BCL-2, and p53, as well as binding of phospho-GSK-3␤ (inactive) to the adenine nucleotide translocase, which suppresses association with cyclophilin D reducing the sensitivity of the mitochondrial permeability transition pore to Ca 2ϩ induced opening (105,106). Notably, elevating O-GlcNAc levels has been shown to reduce opening of the mitochondrial permeability transition pore and to promote the maintenance of mitochondrial membrane potential during ischemia reperfusion injury (48,50,53,54), as such the data presented in this study may provide molecular insight into the mechanisms underlying this phenomena.…”

Mitochondria and aging: A role for the mitochondrial transition pore?

“…An increased phospho‐GSK‐3β binding to ANT was suggested to be responsible for the inhibition of mPTP opening (Miura & Tanno, 2010; Nishihara et al., 2007). This mechanism would contribute to the cardioprotective effect of several drugs such as formononetin or resveratrol and of ischemic preconditioning (Cheng, Xia, Han, & Rong, 2016; Xi, Wang, Mueller, Norfleet, & Xu, 2009; Zhu, Rebecchi, Glass, Brink, & Liu, 2013; Zhu, Rebecchi, Wang, et al., 2013). In the aging heart, failure to reduce ANT/CypD interactions or decreased pGSK‐3β responsiveness of ANT could be responsible for the attenuation of cardioprotection afforded by ischemic preconditioning (Zhu, Rebecchi, Glass, et al., 2013; Zhu, Rebecchi, Wang, et al., 2013).…”

Dose-Dependency of Resveratrol in Providing Health Benefits

“…Careful review of the studies on cancer prevention with resveratrol reveals that in each case, resveratrol was used at high concentration/dose Xi et al 2009;Das et al 2006a;Kaga et al 2005). This would tend to indicate that resveratrol provides diverse health benefits in a doseresponse manner.…”