scholarly journals Release of Mitochondrial Apoptogenic Factors and Cell Death are Mediated by CK2 and NADPH Oxidase

2011 ◽  
Vol 32 (4) ◽  
pp. 720-730 ◽  
Author(s):  
Gab Seok Kim ◽  
Joo Eun Jung ◽  
Purnima Narasimhan ◽  
Hiroyuki Sakata ◽  
Hideyuki Yoshioka ◽  
...  

Activation of the NADPH oxidase subunit, NOX2, and increased oxidative stress are associated with neuronal death after cerebral ischemia and reperfusion. Inhibition of NOX2 by casein kinase 2 (CK2) leads to neuronal survival, but the mechanism is unknown. In this study, we show that in copper/zinc-superoxide dismutase transgenic (SOD1 Tg) mice, degradation of CK2α and CK2α′ and dephosphorylation of CK2β against oxidative stress were markedly reduced compared with wild-type (WT) mice that underwent middle cerebral artery occlusion. Inhibition of CK2 pharmacologically or by ischemic reperfusion facilitated accumulation of poly(ADP-ribose) polymers, the translocation of apoptosis-inducing factor (AIF), and cytochrome c release from mitochondria after ischemic injury. The eventual enhancement of CK2 inhibition under ischemic injury strongly increased 8-hydroxy-2′-deoxyguanosine and phosphorylation of H2A.X. Furthermore, CK2 inhibition by tetrabromocinnamic acid (TBCA) in SOD1 Tg and gp91 knockout (KO) mice after ischemia reperfusion induced less release of AIF and cytochrome c than in TBCA-treated WT mice. Inhibition of CK2 in gp91 KO mice subjected to ischemia reperfusion did not increase brain infarction compared with TBCA-treated WT mice. These results strongly suggest that NOX2 activation releases reactive oxygen species after CK2 inhibition, triggering release of apoptogenic factors from mitochondria and inducing DNA damage after ischemic brain injury.

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Zhihong Lin ◽  
Danni Zhu ◽  
Yongqing Yan ◽  
Boyang Yu ◽  
Qiujuan Wang ◽  
...  

Oxidative stress is involved in the pathogenesis of ischemic neuronal injury. A Chinese herbal formula composed ofPoria cocos(Chinese name:Fu Ling),Atractylodes macrocephala(Chinese name:Bai Zhu) andAngelica sinensis(Chinese names:Danggui, Dong quai, Donggui; Korean name:Danggwi) (FBD), has been proved to be beneficial in the treatment of cerebral ischemia/reperfusion (I/R).This study was carried out to evaluate the protective effect of FBD against neuronal oxidative stressin vivoandin vitro. Rat I/R were established by middle cerebral artery occlusion (MCAO) for 1 h, followed by 24 h reperfusion. MCAO led to significant depletion in superoxide dismutase and glutathione and rise in lipid peroxidation (LPO) and nitric oxide in brain. The neurological deficit and brain infarction were also significantly elevated by MCAO as compared with sham-operated group. All the brain oxidative stress and damage were significantly attenuated by 7 days pretreatment with the aqueous extract of FBD (250 mg kg−1, p.o.). Moreover, cerebrospinal fluid sampled from FBD-pretreated rats protected PC12 cells against oxidative insult induced by 0.2 mM hydrogen peroxide, in a concentration and time-dependent manner (IC5010.6%, ET501.2 h). However, aqueous extract of FBD just slightly scavenged superoxide anion radical generated in xanthine–xanthine oxidase system (IC502.4 mg ml−1) and hydroxyl radical generated in Fenton reaction system (IC503.6 mg ml−1). In conclusion, FBD was a distinct antioxidant phytotherapy to rescue neuronal oxidative stress, through blocking LPO, restoring endogenous antioxidant system, but not scavenging free radicals.


2009 ◽  
Vol 29 (7) ◽  
pp. 1262-1272 ◽  
Author(s):  
Hai Chen ◽  
Yun Seon Song ◽  
Pak H Chan

Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) is well known as a major source for superoxide radical generation in leukocytes. Superoxide radicals play a significant role in brain ischemia–reperfusion (I/R) injury. Recent data have also shown expression of NOX in the brain. However, the manner by which NOX is involved in pathologic processes after cerebral ischemia remains unknown. Therefore, we subjected mice deficient in the NOX subunit, gp91phox (gp91phox-/-), those treated with the NOX inhibitor, apocynin, and wild-type (WT) mice to 75 mins of focal ischemia followed by reperfusion. At 24 h of reperfusion, the gp91phox-/- and apocynin-treated mice showed 50% less brain infarction and 70% less cleaved spectrin compared with WT mice. The levels of 4-hydroxy-2-nonenal, malondialdehyde, and 8-hydroxy-2‘-deoxyguanosine increased significantly after I/R, indicating oxidative brain injury. NADPH oxidase inhibition reduced biomarker generation. Furthermore, NOX was involved in postischemic inflammation in the brains, as less intercellular adhesion molecule-1 upregulation and less neutrophil infiltration were found in the NOX-inhibited mice after I/R. Moreover, gp91phox expression increased after ischemia, and was further aggravated by genetic copper/zinc-superoxide dismutase (SOD1) ablation, but ameliorated in SOD1-overexpressing mice. This study suggests that NOX plays a role in oxidative stress and inflammation, thus contributing to ischemic brain injury.


2009 ◽  
Vol 2 (1) ◽  
pp. 36-42 ◽  
Author(s):  
Takashi Yanagida ◽  
Jun Tsushima ◽  
Yoshihisa Kitamura ◽  
Daijiro Yanagisawa ◽  
Kazuyuki Takata ◽  
...  

Astrocytes, one of the predominant types of glial cells, function as both supportive and metabolic cells for the brain. Under cerebral ischemia/reperfusion-induced oxidative conditions, astrocytes accumulate and activate in the ischemic region. DJ-1 has recently been shown to be a sensor of oxidative stress in living cells. However, the function of astrocytic DJ-1 is still unknown. In the present study, to clarify the effect of astrocytic DJ-1 protein under massive oxidative insult, we used a focal ischemic rat model that had been subjected to middle cerebral artery occlusion (MCAO) and reperfusion. We then investigated changes in the distribution of DJ-1 in astrocytes, DJ-1 release from cultured astrocytes, and the effects of recombinant DJ-1 protein on hydrogen peroxide (H2O2)-induced death in normal and DJ-1-knockdown SH-SY5Y cells and on in vitro scavenging of hydroxyl radicals (•OH) by electron spin resonance spectrometry. At 24 h after 2-h MCAO and reperfusion, an infarct lesion was markedly observed using magnetic resonance imaging and 2,3,5-triphenyltetrazolium chloride staining. In addition, reactive astrocytes enhanced DJ-1 expression in the penumbral zone of the ischemic core and that DJ-1 protein was extracellularly released from astrocytes by H2O2 in in vitro primary cultures. Although DJ-1-knockdown SH-SY5Y cells were markedly vulnerable to oxidative stress, treatment with glutathione S-transferase-tagged recombinant human DJ-1 protein (GST-DJ-1) significantly inhibited H2O2-induced cell death. In addition, GST-DJ-1 protein directly scavenged•OH. These results suggest that oxidative stress induces the release of astrocytic DJ-1 protein, which may contribute to astrocyte-mediated neuroprotection.


2020 ◽  
Vol 2020 ◽  
pp. 1-14 ◽  
Author(s):  
Jing Yu ◽  
Wen-na Wang ◽  
Nathanael Matei ◽  
Xue Li ◽  
Jin-wei Pang ◽  
...  

Oxidative stress and neuroinflammation play essential roles in ischemic stroke-induced brain injury. Previous studies have reported that Ezetimibe (Eze) exerts antioxidative stress and anti-inflammatory properties in hepatocytes. In the present study, we investigated the effects of Eze on oxidative stress and neuroinflammation in a rat middle cerebral artery occlusion (MCAO) model. One hundred and ninety-eight male Sprague-Dawley rats were used. Animals assigned to MCAO were given either Eze or its control. To explore the downstream signaling of Eze, the following interventions were given: AMPK inhibitor dorsomorphin and nuclear factor erythroid 2-related factor 2 (Nrf2) siRNA. Intranasal administration of Eze, 1 h post-MCAO, further increased the endogenous p-AMPK expression, reducing brain infarction, neurologic deficits, neutrophil infiltration, microglia/macrophage activation, number of dihydroethidium- (DHE-) positive cells, and malonaldehyde (MDA) levels. Specifically, treatment with Eze increased the expression of p-AMPK, Nrf2, and HO-1; Romo-1, thioredoxin-interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3), Cleaved Caspase-1, and IL-1β were reduced. Dorsomorphin and Nrf2 siRNA reversed the protective effects of Eze. In summary, Eze decreases oxidative stress and subsequent neuroinflammation via activation of the AMPK/Nrf2/TXNIP pathway after MCAO in rats. Therefore, Eze may be a potential therapeutic approach for ischemic stroke patients.


2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Toshitaka Yajima ◽  
Stanley Park ◽  
Hanbing Zhou ◽  
Michinari Nakamura ◽  
Mitsuyo Machida ◽  
...  

MAVS is a mitochondrial outer membrane protein that activates innate antiviral signaling by recognizing cytosolic viral RNAs and DNAs. While the discovery of MAVS is the first molecular evidence that links mitochondria to innate immune mechanisms, it is still unclear whether MAVS affects mitochondrial cell death as a member of caspase activation and recruitment domain (CARD)-containing proteins. We found that MAVS interacts with Bax through CARD by Yeast two-hybrid and a series of immunoprecipitation (IP) assay, which led us to hypothesize that MAVS functions not only in the innate antiviral mechanisms but also in the mitochondrial cell death pathway. Methods: 1) We examined molecular interaction between MAVS and Bax under oxidative stress by IP using isolated myocytes with H2O2 stimulation and the heart post ischemia-reperfusion (I/R). 2) We evaluated the effect of MAVS on mitochondrial membrane potential and apoptosis under H2O2 stimulation using isolated myocytes with adenoviral MAVS knockdown. 3) We investigated the impact of MAVS on %myocardial infarction (%MI) post I/R using cardiac-specific MAVS knockout (cKO) and transgenic (cTg) mice which we have originally generated. 4) We examined the effect of MAVS on recombinant Bax (rBax)-mediated cytochrome c release using isolated mitochondria from wild type (WT) and MAVS KO mice. Results: 1) The amount of Bax pulled down with MAVS was significantly increased in isolated myocytes with 0.2 mM H2O2 compared to those without stimulation (mean±SD; 1.808±0.14, n=5, p<0.001) and in the heart post I/R compared to sham (2.2±1.19, n=3, p=0.0081). 2) Myocytes with MAVS knockdown showed clear abnormalities in mitochondrial membrane potential and caspace-3 cleavage with 0.2 mM H2O2 compared to control cardiomyocytes. 3) MAVS cKO had significantly larger %MI than WT (81.9 ± 5.8% vs. 42.6 ± 13.6%, n=8, p=0.0008). In contrast, MAVS cTg had significantly smaller %MI that WT (30.0 ± 4.8% vs. 49.2 ± 4.8%, n=10, p=0.0113). 4) Mitochondria from MAVS KO exhibited cytochrome c release after incubation with 2.5 μ g of rBax while those from WT required 10 μ g of rBax. Conclusion: These results demonstrate that MAVS protects cardiomyocyte under oxidative stress by interfering with Bax-mediated cytochrome c release from mitochondria.


2014 ◽  
Vol 21 (8) ◽  
pp. 688-695 ◽  
Author(s):  
Nguyen Huu Tung ◽  
Kai Sun ◽  
Jing-Yu Fan ◽  
Yukihiro Shoyama ◽  
Jing-Yan Han

2005 ◽  
Vol 102 (6) ◽  
pp. 1085-1093 ◽  
Author(s):  
E-Jian Lee ◽  
Ming-Yang Lee ◽  
Guan-Liang Chang ◽  
Li-Hsuan Chen ◽  
Yu-Ling Hu ◽  
...  

Object. The authors examined whether delayed treatment with Mg++ would reduce brain infarction and improve electrophysiological and neurobehavioral recovery following cerebral ischemia—reperfusion. Methods. Male Sprague—Dawley rats were subjected to right middle cerebral artery occlusion for 90 minutes followed by 72 hours of reperfusion. Magnesium sulfate (750 µmol/kg) or vehicle was given via intracarotid infusion at the beginning of reperfusion. Neurobehavioral outcome and somatosensory evoked potentials (SSEPs) were examined before and 72 hours after ischemia—reperfusion. Brain infarction was assessed after the rats had died. Before ischemia—reperfusion, stable SSEP waveforms were recorded after individual fore- and hindpaw stimulations. At 72 hours of perfusion the SSEPs recorded from ischemic fore- and hindpaw cortical fields were depressed in vehicle-injected animals and the amplitudes decreased to 19 and 27% of baseline, respectively (p < 0.001). Relative to controls, the amplitudes of SSEPs recorded from both ischemic fore- and hindpaw cortical field in the Mg++-treated animals were significantly improved by 23% (p < 0.005) and 39% (p < 0.001) of baselines, respectively. In addition, Mg++ improved sensory and motor neurobehavioral outcomes by 34% (p < 0.01) and 24% (p < 0.05), respectively, and reduced cortical (p < 0.05) and striatal (p < 0.05) infarct sizes by 42 and 36%, respectively. Conclusions. Administration of Mg++ at the commencement of reperfusion enhances electrophysiological and neurobehavioral recovery and reduces brain infarction after cerebral ischemia—reperfusion. Because Mg++ has already been used clinically, it may be worthwhile to investigate it further to see if it holds potential benefits for patients with ischemic stroke and for those who will undergo carotid endarterectomy.


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Woranan Kirisattayakul ◽  
Jintanaporn Wattanathorn ◽  
Terdthai Tong-Un ◽  
Supaporn Muchimapura ◽  
Panakaporn Wannanon ◽  
...  

The protection against ischemic stroke is still required due to the limitation of therapeutic efficacy. Based on the role of oxidative stress in stroke pathophysiology, we determined whetherMoringa oleifera, a plant possessing potent antioxidant activity, protected against brain damage and oxidative stress in animal model of focal stroke.M. oleiferaleaves extract at doses of 100, 200 and 400 mg·kg−1was orally given to male Wistar rats (300–350 g) once daily at a period of 2 weeks before the occlusion of right middle cerebral artery (Rt.MCAO) and 3 weeks after Rt.MCAO. The determinations of neurological score and temperature sensation were performed every 7 days throughout the study period, while the determinations of brain infarction volume, MDA level, and the activities of SOD, CAT, and GSH-Px were performed 24 hr after Rt.MCAO. The results showed that all doses of extract decreased infarction volume in both cortex and subcortex. The protective effect of medium and low doses of extract in all areas occurred mainly via the decreased oxidative stress. The protective effect of the high dose extract in striatum and hippocampus occurred via the same mechanism, whereas other mechanisms might play a crucial role in cortex. The detailed mechanism required further exploration.


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