Chrysin attenuates interstitial fibrosis and improves cardiac function in a rat model of acute myocardial infarction

Background Several studies have shown that resveratrol (RES), a naturally occurring polyphenol found in many plants, is beneficial for preventing cardiovascular diseases. However, the mechanism underlying the RES-mediated protection against myocardial infarction has not yet been revealed entirely. In this study, we investigated the protective effects of RES on cardiac function in a rat model of acute myocardial infarction (AMI) and the related underlying mechanisms. Methods Male Sprague-Dawley rats were randomly divided into four groups: Sham (sham operation), Sham-RES, AMI (AMI induction), and AMI-RES. The rat AMI model was established by the permanent ligation of left anterior descending coronary artery method. The rats in the RES-treated groups were gavaged with RES (50 mg/kg/day) daily for 45 days after the Sham operation or AMI induction; rats in the Sham and AMI groups were gavaged with deionized water. Cardiac function was evaluated by echocardiography. Atrial interstitial fibrosis was assessed by hematoxylin-eosin or Masson’s trichrome staining. Real-time PCR and western blotting analyses were performed to examine the levels of signaling pathway components. Results RES supplementation decreased the inflammatory cytokine levels, improved the cardiac function, and ameliorated atrial interstitial fibrosis in the rats with AMI. Furthermore, RES supplementation inhibited NLRP3 inflammasome activity, decreased the TGF-β1 production, and downregulated the p-SMAD2/SMAD2 expression in the heart. Conclusion RES shows notable cardioprotective effects in a rat model of AMI; the possible mechanisms underlying these effects may involve the improvement of cardiac function and atrial interstitial fibrosis via the RES-mediated suppression of NLRP3 inflammasome activity and inhibition of the TGF-β1/SMAD2 signaling pathway in the heart.

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Cortistatin Improves Cardiac Function After Acute Myocardial Infarction in Rats by Suppressing Myocardial Apoptosis and Endoplasmic Reticulum Stress

Journal of Cardiovascular Pharmacology and Therapeutics ◽

10.1177/1074248416644988 ◽

2016 ◽

Vol 22 (1) ◽

pp. 83-93 ◽

Cited By ~ 10

Author(s):

Zhi-Yu Shi ◽

Yue Liu ◽

Li Dong ◽

Bo Zhang ◽

Meng Zhao ◽

...

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Endoplasmic Reticulum ◽

Cardiac Function ◽

Er Stress ◽

Rat Model ◽

Caspase 3 ◽

Apoptotic Pathway ◽

Myocardial Apoptosis ◽

Glucose Regulated Protein

Objectives: The endoplasmic reticulum (ER) stress-induced apoptotic pathway is associated with the development of acute myocardial infarction (AMI). Cortistatin (CST) is a novel bioactive peptide that inhibits apoptosis-related injury. Therefore, we investigated the cardioprotective effects and potential mechanisms of CST in a rat model of AMI. Methods: Male Wistar rats were randomly divided into sham, AMI, and AMI + CST groups. Cardiac function and the degree of infarction were evaluated by echocardiography, cardiac troponin I activity, and 2,3,5-triphenyl-2H-tetrazolium chloride staining after 7 days. The expression of CST, ER stress markers, and apoptotic markers was examined using immunohistochemistry and Western blotting. Results: Compared to the AMI group, the AMI + CST group exhibited markedly better cardiac function and a lower degree of infarction. Electron microscopy and terminal deoxynucleotidyl transferase dUTP nick end labeling confirmed that myocardial apoptosis occurred after AMI. Cortistatin treatment reduced the expression of caspase 3, cleaved caspase 3, and Bax (proapoptotic proteins) and promoted the expression of Bcl-2 (antiapoptotic protein). In addition, the reduced expression of glucose-regulated protein 94 (GRP94), glucose-regulated protein 78 (GRP78), CCAAT/enhancer-binding proteins homologous protein, and caspase 12 indicated that ER stress and the apoptotic pathway associated with ER stress were suppressed. Conclusions: Exogenous CST has a notable cardioprotective effect after AMI in a rat model in that it improves cardiac function by suppressing ER stress and myocardial apoptosis.

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Targeted Cardiac Overexpression of A20 Improves Left Ventricular Performance and Reduces Compensatory Hypertrophy After Myocardial Infarction

Circulation ◽

10.1161/circulationaha.106.656835 ◽

2007 ◽

Vol 115 (14) ◽

pp. 1885-1894 ◽

Cited By ~ 80

Author(s):

Hong-Liang Li ◽

Ming-Lei Zhuo ◽

Dong Wang ◽

Ai-Bing Wang ◽

Hua Cai ◽

...

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Transgenic Mice ◽

Cardiac Function ◽

Cardiac Remodeling ◽

Interstitial Fibrosis ◽

Nuclear Factor Κb ◽

Left Ventricular ◽

Nuclear Factor ◽

Ventricular Performance

Background— A20 was originally characterized as a tumor necrosis factor–inducible gene in human umbilical vein endothelial cells. As an inhibitor of nuclear factor-κB signaling, A20 protects against apoptosis, inflammation, and cardiac hypertrophy. In the present study, we tested the hypothesis that cardiac-specific overexpression of A20 could protect the heart from myocardial infarction. Methods and Results— We investigated the role of constitutive human A20 expression in acute myocardial infarction using a transgenic model. Transgenic mice containing the human A20 gene under the control of the α-myosin heavy chain promoter were constructed. Myocardial infarction was produced by coronary ligation in A20 transgenic mice and control animals. The extent of infarction was then quantified by 2-dimensional and M-mode echocardiography and by molecular and pathological analyses of heart samples in infarct and remote heart regions 7 days after myocardial infarction. Constitutive overexpression of A20 in the murine heart resulted in attenuated infarct size and improved cardiac function 7 days after myocardial infarction. Significantly, we found a decrease in nuclear factor-κB signaling and apoptosis, as well as proinflammatory response, cardiac remodeling, and interstitial fibrosis, in noninfarct regions in the hearts of constitutive A20-expressing animals compared with control animals. Conclusions— Cardiac-specific overexpression of A20 improves cardiac function and inhibits cardiac remodeling, apoptosis, inflammation, and fibrosis after acute myocardial infarction.

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