scholarly journals Diabetes Upregulates Oxidative Stress and Downregulates Cardiac Protection to Exacerbate Myocardial Ischemia/Reperfusion Injury in Rats

Antioxidants ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 679
Author(s):  
Chen-Yen Chien ◽  
Ting-Jui Wen ◽  
Yu-Hsiuan Cheng ◽  
Yi-Ting Tsai ◽  
Chih-Yao Chiang ◽  
...  

Diabetes exacerbates myocardial ischemia/reperfusion (IR) injury by incompletely understood mechanisms. We explored whether diabetes diminished BAG3/Bcl-2/Nrf-2/HO-1-mediated cardioprotection and overproduced oxidative stress contributing to exaggerated IR injury. Streptozotocin-induced diabetes enhanced hyperglycemia, cardiac NADPH oxidase p22/p67 expression, malondialdehyde amount and leukocyte infiltration, altered the mesenteric expression of 4-HNE, CaSR, p-eNOS and BAG3 and impaired microvascular reactivity to the vasoconstrictor/vasodilator by a wire myography. In response to myocardial IR, diabetes further depressed BAG3/Bcl-2/Nrf-2/HO-1 expression, increased cleaved-caspase 3/poly(ADP-ribose) polymerase (PARP)/TUNEL-mediated apoptosis and exacerbated IR-induced left ventricular dysfunction characterized by further depressed microcirculation, heart rate, left ventricular systolic pressure and peak rate of pressure increase/decrease (±dp/dt) and elevated left ventricular end-diastolic pressure (LVEDP) and Evans blue-2,3,5-triphenyltetrazolium chloride-stained infarct size in diabetic hearts. Our results implicated diabetes exacerbated IR-induced myocardial dysfunction through downregulated BAG3/Bcl-2/Nrf-2/HO-1 expression, increased p22/p67/caspase 3/PARP/apoptosis-mediated oxidative injury and impaired microvascular reactivity.

2021 ◽  
Vol 12 ◽  
Author(s):  
Zhenyu Fan ◽  
Liangliang Cai ◽  
Shengnan Wang ◽  
Jing Wang ◽  
Bohua Chen

Baicalin is a natural flavonoid glycoside that confers protection against myocardial ischemia/reperfusion (I/R) injury. However, its mechanism has not been fully understood. This study focused on elucidating the role of ferroptosis in baicalin-generated protective effects on myocardial ischemia/reperfusion (I/R) injury by using the myocardial I/R rat model and oxygen–glucose deprivation/reoxygenation (OGD/R) H9c2 cells. Our results show that baicalin improved myocardial I/R challenge–induced ST segment elevation, coronary flow (CF), left ventricular systolic pressure , infarct area, and pathological changes and prevented OGD/R-triggered cell viability loss. In addition, enhanced lipid peroxidation and significant iron accumulation along with activated transferrin receptor protein 1 (TfR1) signal and nuclear receptor coactivator 4 (NCOA4)-medicated ferritinophagy were observed in in vivo and in vitro models, which were reversed by baicalin treatment. Furthermore, acyl-CoA synthetase long-chain family member 4 (ACSL4) overexpression compromised baicalin-generated protective effect in H9c2 cells. Taken together, our findings suggest that baicalin prevents against myocardial ischemia/reperfusion injury via suppressing ACSL4-controlled ferroptosis. This study provides a novel target for the prevention of myocardial ischemia/reperfusion injury.


Author(s):  
Zi-Long Wang ◽  
Xiao-Chen Sun ◽  
Rong Luo ◽  
Dong-Ye Li ◽  
Hao-Chen Xuan

IntroductionTo explore serum norepinephrine (NE) concentration and β3-adrenoceptor (β3AR) protein expression at different times during myocardial ischemia/reperfusion (I/R) and examine the role of β3AR in I/R.Material and methods28 Sprague-Dawley (SD) rats were randomly divided into one sham group and six I/R groups. The rats in the I/R groups were subjected to ischemia for 45 minutes. After reperfusion, the serum NE concentration and the β3AR protein expression in the myocardial tissue of the left ventricular injury region were detected. Another 18 SD rats were randomly divided into a sham group, I/R groups, and I/R + BRL37344 group.ResultsCompared with the sham group, the serum NE concentration of rats in the I/R groups significantly increased at 6 hours (P < 0.001). The serum NE concentration and myocardial β3AR protein expression were both highest at 72 hours. Compared with the sham group, the expressions of the pro-apoptotic proteins Bax and cleaved caspase-3 after I/R were significantly increased (P < 0.01, P < 0.001, respectively), and the expression of anti-apoptotic protein Bcl-2 was significantly decreased (P < 0.01). Compared with I/R groups, the expressions of Bax and cleaved caspase-3 in the I/R + BRL37344 group were significantly decreased (P < 0.05, P < 0.01, respectively).ConclusionsWith the prolongation of myocardial I/R in rats, serum NE concentration and β3AR protein expression showed a significant increase trend and reached a peak at 72 hours. Specific β3AR agonist BRL37344 can reduce myocardial I/R injury in vivo in rats, alleviate apoptosis, reduce infarct size, and improve cardiac function.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Li-ping Zhang ◽  
Yi-chuan Jiang ◽  
Xiao-feng Yu ◽  
Hua-li Xu ◽  
Min Li ◽  
...  

Objectives. Ginsenoside Rg3 is one of the ginsenosides which are the main constituents isolated from Panax ginseng. Previous study demonstrated that ginsenoside Rg3 had a protective effect against myocardial ischemia/reperfusion- (I/R-) induced injury. Objective. This study was designed to evaluate the effect of ginsenoside Rg3 on cardiac function impairment induced by myocardial I/R in rats. Methods. Sprague-Dawley rats were subjected to myocardial I/R. Echocardiographic and hemodynamic parameters and histopathological examination were carried out. The expressions of P53, Bcl-2, Bax, and cleaved caspase-3 and the levels of TNF-α and IL-1β in the left ventricles were measured. Results. Ginsenoside Rg3 increased a left ventricular fractional shortening and left ventricular ejection fraction. Treatment with ginsenoside Rg3 also alleviated increases of left ventricular end diastolic pressure and decreases of left ventricular systolic pressure and ±dp/dt in myocardial I/R-rats. Ginsenoside Rg3 decreased apoptosis cells through inhibiting the activation of caspase-3. Ginsenoside Rg3 also caused significant reductions of the contents of TNF-α and IL-1β in left ventricles of myocardial I/R-rats. Conclusion. The findings suggested that ginsenoside Rg3 possessed the effect of improving myocardial I/R-induced cardiac function impairment and that the mechanism of pharmacological action of ginsenoside Rg3 was related to its properties of antiapoptosis and anti-inflammation.


2020 ◽  
Vol 40 (6) ◽  
Author(s):  
Wenyuan Li ◽  
Wei Li ◽  
Yan Leng ◽  
Yonghong Xiong ◽  
Rui Xue ◽  
...  

Abstract Ischemic heart disease is the main cardiovascular complication of diabetes patients which is mainly caused by oxidative stress. DJ-1 is the key regulator for myocardial protection through inhibiting phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and activating Akt (also known as PKB or protein kinase B). This research is to investigate whether the antioxidant N-acetylcysteine (NAC) could alleviate diabetic myocardial ischemia/reperfusion (I/R) injury by the protective molecule DJ-1. DJ-1 in rat myocardial H9c2 cells and cardiac tissue was respectively knocked down by siRNA and adeno-associated virus (AAV). From the present study, it could be found that compared with high glucose (HG)-normal (N)/DM group, hypoxia/reoxygenation (H/R) or I/R injury can aggravate oxidative stress injury and apoptosis rate of myocardial cells, inhibit the expression of Bcl-2, activate the BAX and cleaved caspase-3 (c-caspase-3) protein and PTEN/Akt pathway. However, in the groups of HG-N, DM, HG-N+I/R and DM+I/R, NAC can significantly reduce oxidative stress injury and apoptosis rate of myocytes, promote the Bcl-2 and DJ-1 molecules, inhibit BAX and c-caspase-3 protein and PTEN/Akt pathway. Compared with HG-N+I/R+NAC and DM+I/R+NAC groups, the oxidative stress injury, apoptosis rate of myocardial cells and heart tissues increased after the knockdown of DJ-1, the expression of Bcl-2 and DJ-1 were inhibited, the BAX and c-caspase-3 expression was increased, and PTEN/Akt pathway was activated. Taken together, the findings suggest that NAC can reduce I/R injury in diabetic myocardium by up-regulating the PTEN/Akt pathway through the level of DJ-1.


2018 ◽  
Vol 47 (3) ◽  
pp. 1193-1206 ◽  
Author(s):  
Yunyang Lu ◽  
Yingda Feng ◽  
Dan Liu ◽  
Zhiran Zhang ◽  
Kai Gao ◽  
...  

Background/Aims: Myocardial ischemia/reperfusion (MI/R) injury is a leading factor responsible for damage in myocardial infarction, resulting in additional injury to cardiac tissues involved in oxidative stress, inflammation, and apoptosis. Thymoquinone (TQ), the main constituent of Nigella sativa L. seeds, has been reported to possess various biological activities. However, few reports regarding myocardial protection are available at present. Therefore, this study was conducted aiming to investigate the protective effect of TQ against MI/R injury and to clarify its potential mechanism. Methods: MI/R injury models of isolated rat hearts and neonatal rat cardiomyocytes were established. The Langendorff isolated perfused heart system, triphenyltetrazolium chloride staining, gene transfection, TransLaser scanning confocal microscopy, and western blotting were employed to evaluate the cardioprotection effect of TQ against MI/R injury. Results: Compared with the MI/R group, TQ treatment could remarkably improve left ventricular function, decrease myocardial infarct size and production of lactate dehydrogenase (LDH), and attenuate mitochondrial oxidative damage by elevating superoxide dismutase (SOD) activity and reducing production of hydrogen peroxide (H2O2) and malonaldehyde (MDA). Moreover, the cardioprotective effect of TQ was accompanied by up-regulated expression of SIRT1 and inhibition of p53 acetylation. Additionally, TQ treatment could also enhance mitochondrial function and reduce the number of apoptotic cardiomyocytes. Nonetheless, the cardioprotective effect of TQ could be mitigated by SIRT1 inhibitor sirtinol and SIRT1 siRNA, respectively, which was achieved through inhibition of the SIRT1 signaling pathway. Conclusions: The findings in this study demonstrate that TQ is efficient in attenuating MI/R injury through activation of the SIRT1 signaling pathway, which can thus reduce mitochondrial oxidative stress damage and cardiomyocyte apoptosis.


2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Dong Wang ◽  
Xin Guo ◽  
Mingjie Zhou ◽  
Jichun Han ◽  
Bo Han ◽  
...  

This study was conducted to evaluate the cardioprotective property of the aqueous extract of lavender flower (LFAE). The myocardial ischemia/reperfusion (I/R) injury of rat was prepared by Langendorff retrograde perfusion technology. The heart was preperfused with K-H solution containing LFAE for 10 min before 20 minutes global ischemia, and then the reperfusion with K-H solution was conducted for 45 min. The left ventricular developed pressure (LVDP) and the maximum up/downrate of left ventricular pressure (±dp/dtmax) were recorded by physiological recorder as the myocardial function and the myocardial infarct size was detected by TTC staining. Lactate dehydrogenase (LDH) and creatine kinase (CK) activities in the effluent were measured to determine the myocardial injury degree. The superoxide anion dismutase (SOD) and malondialdehyde (MDA) in myocardial tissue were detected to determine the oxidative stress degree. The results showed that the pretreatment with LFAE significantly decreased the myocardial infarct size and also decreased the LDH, CK activities, and MDA level, while it increased the LVDP, ±dp/dtmax, SOD activities, and the coronary artery flow. Our findings indicated that LFAE could provide protection for heart against the I/R injury which may be related to the improvement of myocardial oxidative stress states.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Mingjie Zhou ◽  
Huanhuan Ren ◽  
Jichun Han ◽  
Wenjuan Wang ◽  
Qiusheng Zheng ◽  
...  

Objective. This study aimed to evaluate the protective effect of kaempferol against myocardial ischemia/reperfusion (I/R) injury in rats.Method. Left ventricular developed pressure (LVDP) and its maximum up/down rate (±dp/dtmax) were recorded as myocardial function. Infarct size was detected with 2,3,5-triphenyltetrazolium chloride staining. Cardiomyocyte apoptosis was determined using terminal deoxynucleotidyl nick-end labeling (TUNEL). The levels of creatine kinase (CK), lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione/glutathione disulfide (GSH/GSSG) ratio, and tumor necrosis factor-alpha (TNF-α) were determined using enzyme linked immunosorbent assay (ELISA). Moreover, total glycogen synthase kinase-3β(GSK-3β), phospho-GSK-3β(P-GSK-3β), precaspase-3, cleaved caspase-3, and cytoplasm cytochrome C were assayed using Western blot analysis.Results. Pretreatment with kaempferol significantly improved the recovery of LVDP and±dp/dtmax, as well as increased the levels of SOD and P-GSK-3βand GSH/GSSG ratio. However, the pretreatment reduced myocardial infarct size and TUNEL-positive cell rate, as well as decreased the levels of cleaved caspase-3, cytoplasm cytochrome C, CK, LDH, MDA, and TNF-α.Conclusion. These results suggested that kaempferol provides cardioprotection via antioxidant activity and inhibition of GSK-3βactivity in rats with I/R.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6383 ◽  
Author(s):  
Zhenqiu Tang ◽  
Chunjuan Yang ◽  
Baoyan Zuo ◽  
Yanan Zhang ◽  
Gaosong Wu ◽  
...  

Background Taxifolin (TAX), is an active flavonoid, that plays an underlying protective role on the cardiovascular system. This study aimed to evaluate its effect and potential mechanisms on myocardial ischemia/reperfusion (I/R) injury. Methods Healthy rat heart was subjected to I/R using the Langendorff apparatus. Hemodynamic parameters, including heart rate, left ventricular developed pressure (LVDP), maximum/minimum rate of the left ventricular pressure rise (+dp/dtmax and −dp/dtmin) and rate pressure product (RPP) were recorded during the perfusion. Histopathological examination of left ventricular was measured by hematoxylin-eosin (H&E) staining. Creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) activities in the effluent perfusion, and the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX) in the tissue were assayed. Apoptosis related proteins, such as B-cell lymphoma-2 (Bcl-2), Bcl2-associated X (Bax), and cytochrome c (Cyt-c) were also assayed by ELISA. Western blot was employed to determine apoptosis-executive proteins, including caspase 3 and 9. Transferase-mediated dUTP-X nick end labeling assay was performed to evaluate the effect TAX on myocardial apoptosis. Results Taxifolin significantly improved the ventricular functional recovery, as evident by the increase in LVDP, +dp/dtmax, −dp/dtmin and RPP, the levels of SOD, GSH-PX were also increased, but those of LDH, CK-MB, and MDA were decreased. Furthermore, TAX up-regulated the Bcl-2 protein level but down-regulated the levels of Bax, Cyt-c, caspase 3 and 9 protein, thereby inhibits the myocardial apoptosis. Discussion Taxifolin treatment remarkably improved the cardiac function, regulated oxidative stress and attenuated apoptosis. Hence, TAX has a cardioprotective effect against I/R injury by modulating mitochondrial apoptosis pathway.


2009 ◽  
Vol 106 (6) ◽  
pp. 1993-2001 ◽  
Author(s):  
Robert M. Osipov ◽  
Michael P. Robich ◽  
Jun Feng ◽  
Richard T. Clements ◽  
Yuhong Liu ◽  
...  

Myocardial ischemia-reperfusion (IR) injury occurs frequently in the setting of hypercholesterolemia. We investigated the potential efficacy of a novel thrombin fragment (TP508) on IR injury in a hypercholesterolemic porcine model. Twenty-one hypercholesterolemic male Yucatan pigs underwent 60 min of mid-left anterior descending coronary artery occlusion followed by 120 min of reperfusion. Pigs received either placebo (control, n = 7) or TP508 in two doses (TP508 low dose, n = 7, as bolus of 0.5 mg/kg 50 min into ischemia and an infusion of 1.25 mg·kg−1·h−1 during reperfusion period or TP508 high dose, n = 7, a double dose of TP508 low-dose group). Myocardial function was monitored throughout the experiment. The area at risk and myocardial necrosis were determined by Monastryl blue/triphenyl tetrazolium chloride staining. Apoptosis in the ischemic territory was assessed. Coronary microvascular reactivity to endothelium-dependent and -independent factors was measured. Myocardial necrosis was lower in both TP508-treated groups vs. control ( P < 0.05). Regional left ventricular function was improved only in the TP508 high-dose group ( P < 0.05). Endothelium-dependent coronary microvascular reactivity was greater in both TP508-treated groups ( P < 0.05) vs. control. The expression of proteins favoring cell survival, 90-kDa heat shock protein and phospho-Bad (Ser112) was higher in the TP508 high-dose group ( P < 0.05). The expression of the cell death signaling proteins, cleaved caspase-3 ( P < 0.05), apoptosis-inducing factor ( P < 0.05), and poly-ADP ribose polymerase ( P = 0.07) was lower in the TP508 low-dose group vs. TP508 high-dose and control. The terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling positive cell count was lower in both TP508 groups compared with the control ( P < 0.05). This study demonstrates that, in hypercholesterolemic pigs, TP508 decreases myocardial necrosis and apoptosis after IR. Thus TP508 may offer a novel approach in protecting the myocardium from IR injury.


2017 ◽  
Vol 42 (6) ◽  
pp. 2295-2306 ◽  
Author(s):  
Waleed Al-Herz ◽  
Fawzi Babiker

Background/Aims: To investigate the cardioprotective effects of intravenous immunoglobulins (IVIG) in rats subjected to regional myocardial ischemia reperfusion (I/R). Methods: Langendorff-perfused rat hearts were used in this study. Hearts subjected to regional ischemia served as a negative untreated control. The effects of IVIG pre- and post-ischemic treatment on left ventricular function, coronary vascular dynamics and contractility were assessed. IVIG were administered in either a low or high dose. The infarct size was determined using triphenyltetrazolium chloride and through biochemical assays using the measured creatine kinase and lactate dehydrogenase levels. Apoptosis was evaluated by the TUNEL assay, and the caspase-3 expression level was assessed by immunoblotting. The cytokine levels were measured by ELISA. Results: Low and high doses of immunoglobulins administered 2 hours before sacrifice, before the ischemic insult or at reperfusion resulted in a significant improvement in cardiac hemodynamics, coronary vascular dynamics and heart contractility. A significant decrease in the infarct size and cardiac enzymes was also evident compared to those in the control. IVIG administered as an infusion at reperfusion or pre-treatment resulted in a marked decrease in myocyte apoptosis, which was associated with decreased levels of caspase-3 expression in the supernatants of homogenized left ventricles. Infusion of IVIG both pre-ischemia and at reperfusion did not show the same protective effects. Conclusions: This study demonstrates a novel protection to the heart by low and high doses of IVIG given either pre- or post-ischemia.


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