Vagal Nerve Stimulation During Acute Ischemia Prevents Reperfusion Injury and Promotes Functional Recovery Through Inhibition of Opening of Mitochondrial Permeability Transition Pore

2007 ◽  
Vol 13 (6) ◽  
pp. S41
Author(s):  
Rajesh G. Katare ◽  
Takayuki Sato
Keyword(s):  
Reperfusion Injury ◽  
Functional Recovery ◽  
Nerve Stimulation ◽  
Mitochondrial Permeability Transition Pore ◽  
Mitochondrial Permeability Transition ◽  
Permeability Transition Pore ◽  
Permeability Transition ◽  
Vagal Nerve ◽  
Acute Ischemia ◽  
Mitochondrial Permeability

Antioxidant MCI-186 inhibits mitochondrial permeability transition pore and upregulates Bcl-2 expression

2003 ◽  
Vol 285 (5) ◽  
pp. H2171-H2178 ◽  
Author(s):  
Katare Gopalrao Rajesh ◽  
Shiro Sasaguri ◽  
Ryoko Suzuki ◽  
Hironori Maeda
Keyword(s):  
Cytochrome C ◽  
Reperfusion Injury ◽  
Mitochondrial Permeability Transition Pore ◽  
Mitochondrial Permeability Transition ◽  
Permeability Transition Pore ◽  
Permeability Transition ◽  
Acute Ischemia ◽  
Radical Scavenger ◽  
Cytochrome C Release ◽  
Mitochondrial Permeability

Reperfusion after a period of ischemia is associated with the formation of reactive oxygen species (ROS) and Ca2+ overload resulting in the opening of a nonspecific pore in the inner membrane of the mitochondria, called the mitochondrial permeability transition pore (PTP), leading to cell damage. Although endogenous antioxidants are activated because of oxidative stress following ischemia, their levels are not high enough to prevent reperfusion injury. Hence there is always a need for exogenous supplement of antioxidants, especially after acute ischemia. Here we demonstrated the effects of the antioxidant 3-methyl-1-phenyl-2-pyrazolin-5-one (MCI-186) in preventing reperfusion injury of the heart by inhibition of PTP opening. Ischemia (30 min) by left coronary artery (LCA) occlusion and reperfusion (120 min) in Wistar rats after pretreatment with MCI-186 (10 mg/kg iv) infusion starting from 30 min before LCA occlusion resulted in 1) less area of myocardial infarction (19.2% vs. 61.6%), 2) well-maintained myocardial ATP content ( P < 0.03 vs. control), 3) decreased mitochondrial swelling and reduced cytochrome c release, 4) increased expression of BCl-2, 5) lower prevalence of apoptotic cells (14.3% vs. 2.9%), and 6) reduced DNA fragmentation in the MCI-186-treated group. These cytoprotective effects of MCI-186 were inhibited on opening PTP before MCI-186 treatment with the PTP activators lonidamine (10 mg/kg iv) or atractyloside (5 mg/kg iv) but failed to inhibit the protective effects exerted by another antioxidant, allopurinol, suggesting that the PTP inhibiting property is specific for MCI-186. These results demonstrate that the radical scavenger MCI-186, by inhibiting the opening of the PTP, prevents necrosis and cytochrome c release and hence pathological apoptosis.

Abstract 168: Resveratrol Translocates Gsk-3β To Mitochondria And Protects The Heart At Reperfusion By Targeting The Mitochondrial Permeability Transition Pore

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Jinkun Xi ◽  
Huihua Wang ◽  
Guillaume Chanoit ◽  
Guang Cheng ◽  
Robert A Mueller ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Mitochondrial Permeability Transition Pore ◽  
Mitochondrial Permeability Transition ◽  
Permeability Transition Pore ◽  
Permeability Transition ◽  
Cyclophilin D ◽  
Risk Zone ◽  
Mitochondrial Permeability ◽  
Mptp Opening ◽  
Gsk 3Β

Although resveratrol has been demonstrated to be cardioprotective, the detailed cellular and molecular mechanisms that mediate the protection remain elusive. We aimed to determine if resveratrol protects the heart at reperfusion by modulating the mitochondrial permeability transition pore (mPTP) opening through glycogen synthase kinase 3β (GSK-3β). Resveratrol (10μM) given at reperfusion reduced infarct size (12.2 ± 2.5 % of risk zone vs. 37.9 ± 3.1 % of risk zone in control, n = 6) in isolated rat hearts subjected to 30 min regional ischemia followed by 2 h of reperfusion, an effect that was abrogated by the mPTP opener atractyloside (30.9 ± 8.1 % of risk zone), implying that resveratrol may protect the heart at reperfusion by modulating the mPTP opening. To define the signaling mechanism underlying the action of resveratrol, we determined GSK-3β activity by measuring its phosphorylation at Ser 9 . Resveratrol significantly enhanced GSK-3β phosphorylation upon reperfusion (225.2 ± 30.0 % of control at 5 min of reperfusion). Further experiments showed that resveratrol induces translocation of GSK-3β to mitochondria and translocated GSK-3β interacts with the mPTP component cyclophilin D but not VDAC (the voltage-dependent anion channel) or ANT (the adenine nucleotide translocator) in cardiac mitochondria. Taken together, these data suggest that resveratrol prevents myocardial reperfusion injury by targeting the mPTP opening via GSK-3β. Translocation of GSK-3β to mitochondria and its interaction with the mPTP component cyclophilin D may serve as an essential mechanism that mediates the protective effect of resveratrol on reperfusion injury.

scholarly journals Astragaloside IV Inhibits Oxidative Stress-Induced Mitochondrial Permeability Transition Pore Opening by Inactivating GSK-3βvia Nitric Oxide in H9c2 Cardiac Cells

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Yonggui He ◽  
Jinkun Xi ◽  
Huan Zheng ◽  
Yidong Zhang ◽  
Yuanzhe Jin ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Reperfusion Injury ◽  
Mitochondrial Permeability Transition Pore ◽  
Mitochondrial Permeability Transition ◽  
Permeability Transition Pore ◽  
Permeability Transition ◽  
H9c2 Cells ◽  
Astragaloside Iv ◽  
Mitochondrial Permeability ◽  
Mptp Opening

Objective. This study aimed to investigate whether astragaloside IV modulates the mitochondrial permeability transition pore (mPTP) opening through glycogen synthase kinase 3β(GSK-3β) in H9c2 cells.Methods. H9c2 cells were exposed to astragaloside IV for 20 min. GSK-3β(Ser9), Akt (Ser473), and VASP (Ser239) activities were determined with western blot. The mPTP opening was evaluated by measuring mitochondrial membrane potential (ΔΨm). Nitric oxide (NO) generation was measured by 4-amino-5-methylamino-2′,7′-difluorofluorescein (DAF-FM) diacetate. Fluorescence images were obtained with confocal microscopy.Results. Astragaloside IV significantly enhanced GSK-3βphosphorylation and prevented H2O2-induced loss ofΔΨm. These effects of astragaloside IV were reversed by the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002, the NO sensitive guanylyl cyclase selective inhibitor ODQ, and the PKG inhibitor KT5823. Astragaloside IV activated Akt and PKG. Astragaloside IV was also shown to increase NO production, an effect that was reversed by L-NAME and LY294002. Astragaloside IV applied at reperfusion reduced cell death caused by simulated ischemia/reperfusion, indicating that astragaloside IV can prevent reperfusion injury. Conclusions. These data suggest that astragaloside IV prevents the mPTP opening and reperfusion injury by inactivating GSK-3βthrough the NO/cGMP/PKG signaling pathway. NOS is responsible for NO generation and is activated by the PI3K/Akt pathway.

Sign in / Sign up

Export Citation Format

Share Document