iridoids and Myocardial-Infarction

Background and aims: Genipin, an iridoid derived from geniposide by β-glucosidase hydrolysis, has shown potential benefit in the treatment of heart function insufficiency despite its unclear therapeutic mechanism. This study aimed to investigate the primary cardioprotective mechanism of genipin. We hypothesized that genipin demonstrated the antiapoptosis and anti-inflammation for cardiac protection by inhibiting the cyclooxidase 2 (COX2)-prostaglandin D2 (PGD2) and murine double minute 2 (MDM2)-p53 pathways. Methods: The normal Sprague-Dawley rats were made into myocardial infarction models by conventional methods. Animals were treated with genipin for 5 weeks after myocardial infarction (MI). Morphometric and hemodynamic measurements were performed 5 weeks post-MI. Biological and molecular experiments were performed after the termination. Results: Both morphometry and hemodynamics in systole and diastole were significantly impaired in the model group but restored close to basal level after treatment with genipin. Genipin also restored the post-MI upregulated expressions of cytochrome c, p53, COX2, and PGD2 and downregulated expression of MDM2 to the approximate baseline. Genipin inhibited apoptotic and inflammatory pathways to prevent post-MI structure-function remodeling. Conclusions: This study showed the cardioprotective mechanism of genipin and implied its potential clinical application for the treatment of ischemic heart failure.

Topics: Animals; Cyclooxygenase 2; Heart Failure; Iridoids; Myocardial Infarction; Prostaglandin D2; Rats; Rats, Sprague-Dawley; Signal Transduction; Tumor Suppressor Protein p53

Geniposide (GP), extracted from a traditional Chinese herb Gardenia jasminoides, has extensive pharmacological effects. But the effects and the potential mechanisms of GP on myocardial ischemia/reperfusion (I/R) injury are poorly understood. In present study, we investigated the effect of GP on myocardial I/R injury in vivo and hypoxia/reoxygenation (H/R) in vitro respectively, and its mechanism. The results showed that GP reduced myocardial infarct size, alleviated acute myocardial injury, improved cardiac function, regulated apoptosis-related proteins and inhibited apoptosis. In vitro experiments revealed that GP enhanced the cell viability, regulated apoptosis-related proteins and prevented cell apoptosis during H/R in H9c2 cells. GP inhibited the expression of autophagy-related proteins and autophagosome accumulation both in vivo and in vitro. The effects of GP were blocked by rapamycin (RAPA) administration. In summary, our results showed that GP protected against myocardial I/R injury and involved inhibition of autophagy, which might be through activating AKT/mTOR signaling pathways.

Topics: Animals; Apoptosis; Autophagosomes; Autophagy; Cardiotonic Agents; Cell Line; Cell Survival; Heart; Iridoids; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Myocytes, Cardiac; Proto-Oncogene Proteins c-akt; Rats, Sprague-Dawley; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).\ \ This article has been retracted at the request of the Editor-in-Chief.\ \ Given the comments of Dr Elisabeth Bik regarding this article “… the Western blot bands in all 400+ papers are all very regularly spaced and have a smooth appearance in the shape of a dumbbell or tadpole, without any of the usual smudges or stains. All bands are placed on similar looking backgrounds, suggesting they were copy/pasted from other sources, or computer generated”, the journal requested the authors to provide the raw data. However, the authors were not able to fulfil this request and therefore the Editor-in-Chief decided to retract the article.

Topics: Animals; Apoptosis; Cell Hypoxia; Cell Line; Cytoprotection; Down-Regulation; Gene Silencing; Heart; Iridoids; Janus Kinase 1; Myocardial Infarction; Myocytes, Cardiac; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Rats; RNA, Long Noncoding; Signal Transduction; STAT3 Transcription Factor

Many studies reported that air pollution particulate matter (PM) exposure was associated with myocardial infarction (MI). Acrolein representing the unsaturated aldehydes, the main component of PM, derives from the incomplete combustion of wood, plastic, fossil fuels and the main constitute of cigarette smoking. However, the effect of acrolein on MI remains not that clear. In the current study, the effect of acrolein-exacerbated MI was investigated. In vivo, male Sprague-Dawley rats received olive leaf extract (OLE) followed by acrolein, then isoprenaline (ISO) was received by subcutaneous injection to induce MI. Results showed that the expression levels of GRP78 and CHOP, two major components of endoplasmic reticulum (ER) stress were higher in the combination of acrolein and ISO than those in ISO treatment. The apoptosis marker, Bax, was also higher while the anti-apoptosis indicator, Bcl2 expression was lower both at protein and mRNA levels in the combination group. Also, the acrolein-protein adducts and myocardial pathological damage increased in the combination of acrolein and ISO relative to the ISO treatment. Besides, cardiac parameters, ejection fraction (EF) and fractional shortening (FS) were reduced more significantly when acrolein was added than in ISO treatment. Interestingly, all the changes were able to be ameliorated by OLE. Since hydroxytyrosol (HT) and oleuropein (OP) were the main components in OLE, we next investigated the effect of HT and OP on cardiomyocyte H9c2 cell apoptosis induced by acrolein through ER stress and Bax pathway. Results showed that GRP78, CHOP and Bax expression were upregulated, while Bcl2 expression was downregulated both at the protein and mRNA levels, when the H9c2 cells were treated with acrolein. In addition, pretreatment with HT can reverse the expression of GRP78, CHOP, Bax and Bcl2 on the protein and mRNA levels, while there was no effect of OP on the expression of GRP78 and CHOP on the mRNA levels. Overall, all these results demonstrated that OLE and the main components (HT and OP) could prevent the negative effects of acrolein on myocardium and cardiomyocytes.

Topics: Acrolein; Animals; Apoptosis; Biological Products; Biomarkers; Cell Line; Cytoprotection; Disease Progression; Endoplasmic Reticulum Stress; Iridoid Glucosides; Iridoids; Isoproterenol; Male; Myocardial Infarction; Myocytes, Cardiac; Particulate Matter; Phenylethyl Alcohol; Rats; Rats, Sprague-Dawley

BACKGROUND Revascularization is a successful therapeutic strategy for myocardial infarction. However, restoring coronary blood flow can lead to ischemia-reperfusion (I/R) injury. Low-dose 4-hydroxy-2-nonenal (HNE) therapy appears to play a key role in myocardial tolerance to I/R injury. We hypothesized that the positive effects of HNE on myocardial I/R injury may be UCP3-dependent. MATERIAL AND METHODS Adult male wild-type (WT) or UCP3 knockout (UCP3-/-) mice were pre-treated with the UCP inhibitor genipin or saline 1 h before ischemia and underwent 30-min coronary artery ligation followed by 24-h reperfusion. Mice were treated with intravenous HNE (4 mg/kg) or saline 5 min before reperfusion. Echocardiography was conducted to measure left ventricular end-diastolic posterior wall thickness (LVPWd), end-diastolic diameter (LVEDD), and fractional shortening (FS). Infarct size was measured by TTC staining. qRT-PCR and Western blotting were used to assess the expression of UCP3, UCP2, and the apoptosis markers cytochrome C and cleaved caspase-3. RESULTS HNE improved survival at 24 h post-MI in wild-type mice (p<0.05) but not in UCP3-/- mice. HNE preserved LVEDD and FS in WT mice (p<0.05) but not in UCP3-/- mice. HNE reduced infarct size in WT mice (p<0.05) but not in UCP3-/- mice. HNE upregulated UCP3 expression (p<0.05) but did not affect UCP2 expression. HNE reduced apoptosis marker expression in WT mice (p<0.05) but not in UCP3-/- mice. HNE's positive effects were abrogated by genipin in an UCP3-dependent manner. CONCLUSIONS Low-dose HNE reperfusion therapy attenuates murine myocardial I/R injury in an UCP3-dependent manner. These effects are abrogated by genipin in an UCP3-dependent manner.

Topics: Aldehydes; Animals; Apoptosis; Coronary Vessels; Heart; Iridoids; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Myocardial Infarction; Myocardial Reperfusion; Myocardial Reperfusion Injury; Myocardium; Reperfusion Injury; Uncoupling Protein 3

Much of the beneficial effects of olive products have been attributed to oleuropein. This study examined the effects of oleuropein in rats with heart failure induced by permanent ligation of left coronary arteries. Twenty-four hours after the operation, the rats were assigned to five groups including a sham assigned to receive vehicle (1 ml/day) and four coronary ligated groups assigned to receive vehicle or oleuropein at 5, 10, or 20 mg/kg/day. Five weeks later, echocardiographic and hemodynamic parameters, serum concentrations of oxidative stress, and inflammatory markers were determined. Myocardial infarction group receiving vehicle showed impaired hemodynamic and echocardiographic parameters as evidenced by decreased left ventricular systolic pressure, rate of rise and decrease of left ventricular pressure, stroke volume, ejection fraction, and cardiac output. In addition, significant reduction in superoxide dismutase and glutathione reductase was observed. Oleuropein treatment prevented the reduction of these variables. Moreover, the group had a significantly higher infarct size and serum malondialdehyde, interleukin-1β, and tumor necrosis factor-α than those of the sham group. Treatment with oleuropein prevented the increase of these variables. The results show that oleuropein attenuates the progression of heart failure, possibly by antioxidative and antiinflammatory effects.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Biomarkers; Disease Models, Animal; Disease Progression; Glutathione Reductase; Heart Failure; Hemodynamics; Inflammation Mediators; Interleukin-1beta; Iridoid Glucosides; Iridoids; Male; Malondialdehyde; Myocardial Infarction; Oxidative Stress; Rats, Sprague-Dawley; Superoxide Dismutase; Tumor Necrosis Factor-alpha; Ventricular Function, Left

Injectable scaffolds for cardiac tissue regeneration are a promising therapeutic approach for progressive heart failure following myocardial infarction (MI). Their major advantage lies in their delivery modality that is considered minimally invasive due to their direct injection into the myocardium. Biomaterials comprising such scaffolds should mimic the cardiac tissue in terms of composition, structure, mechanical support, and most importantly, bioactivity. Nonetheless, natural biomaterial-based gels may suffer from limited mechanical strength, which often fail to provide the long-term support required by the heart for contraction and relaxation. Here we present newly-developed injectable scaffolds, which are based on solubilized decellularized porcine cardiac extracellular matrix (pcECM) cross-linked with genipin alone or engineered with different amounts of chitosan to better control the gel's mechanical properties while still leveraging the ECM biological activity. We demonstrate that these new biohybrid materials are naturally remodeled by mesenchymal stem cells, while supporting high viabilities and affecting cell morphology and organization. They exhibit neither in vitro nor in vivo immunogenicity. Most importantly, their application in treating acute and long term chronic MI in rat models clearly demonstrates the significant therapeutic potential of these gels in the long-term (12weeks post MI). The pcECM-based gels enable not only preservation, but also improvement in cardiac function eight weeks post treatment, as measured using echocardiography as well as hemodynamics. Infiltration of progenitor cells into the gels highlights the possible biological remodeling properties of the ECM-based platform.. This work describes the development of new injectable scaffolds for cardiac tissue regeneration that are based on solubilized porcine cardiac extracellular matrix (ECM), combined with natural biomaterials: genipin, and chitosan. The design of such scaffolds aims at leveraging the natural bioactivity and unique structure of cardiac ECM, while overcoming its limited mechanical strength, which may fail to provide the long-term support required for heart contraction and relaxation. Here, we present a biocompatible gel-platform with custom-tailored mechanical properties that significantly improve cardiac function when injected into rat hearts following acute and chronic myocardial infarction. We clearly demonstrate the substantial therapeutic potential of these scaffolds, which not only preserved heart functions but also alleviated MI damage, even after the formation of a mature scar tissue.

Topics: Animals; Cell Line; Chitosan; Extracellular Matrix; Humans; Hydrogels; Iridoids; Male; Mesenchymal Stem Cells; Mice; Myocardial Infarction; Myocardium; Rats; Rats, Wistar; Tissue Scaffolds

Acute myocardial infarction (MI) leads to morbidity and mortality due to cardiac dysfunction. Here we identify sericin, a silk-derived protein, as an injectable therapeutic biomaterial for the minimally invasive MI repair. For the first time, sericin prepared in the form of an injectable hydrogel has been utilized for cardiac tissue engineering and its therapeutical outcomes evaluated in a mouse MI model. The injection of this sericin hydrogel into MI area reduces scar formation and infarct size, increases wall thickness and neovascularization, and inhibits the MI-induced inflammatory responses and apoptosis, thereby leading to a significant functional improvement. The potential therapeutical mechanisms have been further analyzed in vitro. Our results indicate that sericin downregulates pro-inflammatory cytokines (TNF-α and IL-18) and chemokine (CCL2) and reduces TNF-α expression by suppressing the TLR4-MAPK/NF-κB pathways. Moreover, sericin exhibits angiogenic activity by promoting migration and tubular formation of human umbilical vessel endothelial cells (HUVECs). Also, sericin stimulates VEGFa expression via activating ERK phosphorylation. Further, sericin protects endothelial cells and cardiomyocytes from apoptosis by inhibiting the activation of caspase 3. Together, these diverse biochemical activities of sericin protein lead to a significant recovery of cardiac function. This work represents the first study reporting sericin as an effective therapeutic biomaterial for ischemic myocardial repair in vivo.. Intramyocardial biomaterial injection is thought to be a potential therapeutic approach to improve cardiac performance after ischemic myocardial infarction. In this study, we report the successful fabrication and in vivo application of an injectable sericin hydrogel for ischemic heart disease. We for the first time show that the injection of in situ forming crosslinked sericin hydrogel promotes heart functional recovery accompanied with reduced inflammatory responses, attenuated apoptosis and increased microvessel density in the infarcted hearts. Further, we reveal that the improvement in those aspects is ascribed to sericin protein's functional bioactivities that are comprehensively uncovered in this study. Thus, we identify sericin, a natural protein, as a biomaterial suitable for myocardial repair and demonstrate that the in vivo application of this injectable sericin hydrogel can be an effective strategy for treating MI.

Topics: Animals; Apoptosis; Cell Movement; Cross-Linking Reagents; Cytokines; Cytoprotection; Fibrosis; Human Umbilical Vein Endothelial Cells; Hydrogel, Polyethylene Glycol Dimethacrylate; Inflammation; Injections; Iridoids; Male; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Myocardial Infarction; Myocytes, Cardiac; Neovascularization, Physiologic; NIH 3T3 Cells; Rats; Recovery of Function; Sericins; Transcription, Genetic; Vascular Endothelial Growth Factor A

Myocardial infarction causes a cascade of events, which leads to heart failure, debilitation and death. This study examined possible cardioprotective effect of oleuropein in rats with acute myocardial infarction. Male Sprague-Dawly rats were allocated to five groups: sham, myocardial infarction receiving vehicle, and three myocardial infarction receiving oleuropein at 10, 20, and 30 mg/kg/day for 7 days, and underwent sham operation or coronary ligation. Twenty-four hours later, animals underwent echocardiographic and hemodynamic studies, and infarct areas, serum concentrations of oxidative stress and inflammatory markers were determined. Myocardial infarction group receiving vehicle had significantly lower left ventricular developed and systolic pressures, rate of rise/decrease of left ventricular pressure, stroke volume, ejection fraction and cardiac output, and serum superoxide dismutase and glutathione reductase than those of sham group. Pretreatment with oleuropein prevented the reduction of these variables. Moreover, the group had a significantly higher serum malondialdehyde, interleukin-1β, TNF-α, creatin kinase-MB, and troponin I, lactate dehydrogenase, and infarct area than those of sham group. Pretreatment with oleuropein prevented the increase of these variables. The findings indicate that coronary ligation results in acute myocardial infarction characterized by impaired cardiac function, and oleuropein pretreatment prevented cardiac impairment partly by reducing oxidative stress and release of proinflammatory cytokines.

Topics: Animals; Biomarkers; Cardiotonic Agents; Creatine Kinase, MB Form; Disease Models, Animal; Electrocardiography; Hemodynamics; Interleukin-1beta; Iridoid Glucosides; Iridoids; L-Lactate Dehydrogenase; Male; Malondialdehyde; Myocardial Infarction; Oxidative Stress; Rats; Rats, Sprague-Dawley; Troponin I; Tumor Necrosis Factor-alpha; Ultrasonography; Vasodilator Agents

Myocardial infarction remains the major cause of global death due to cardiovascular diseases. This study aimed to assess the protective role of oleuropein in attenuating the cardiac remodeling in isoproterenol-induced myocardial infarction in rats.. Male Wistar rats were randomly divided into four groups, control, isoproterenol (Isop) and pretreated animals with oleuropein at two different doses (20 and 40 mg/kg) orally for 7 days and intoxicated with isoproterenol (Isop+Oleu20) and (Isop+Oleu40) groups. The subcutaneous injection of isoproterenol (100 mg/kg body weight) to untreated rats for two consecutive days showed significant increases in ST-segment elevation, heart weight index and alteration in the ECG pattern and hemodynamic function. Else, serum levels of cardiac troponin-T, creatine kinase isoenzyme (CK-MB), lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) underwent a notable rise in serum of Isop group by (345, 82, 73 and 106%, respectively) as compared to normal rats. Isoproterenol-induced myocardial injury was evidenced by alteration in serum lipids profile and increased activities of pancreatic lipase by 94% and angiotensin-converting enzyme (ACE) by 78% which reflects the occurrence of cardiac remodeling process. The histopathological findings of the infarcted group showed myocardium necrosis and cells inflammatory infiltration. However, the treatment with oleuropein gave a good protection of the myocardium by decreasing cardiac injury markers specially troponin-T, restoring hemodynamic parameters and attenuating cardiac remodeling process through inhibition of ACE activity.. Oleuropein offers high preventive effects from cardiac remodeling process in rats with acute myocardial infarction.

Topics: Adrenergic beta-Agonists; Angiotensin-Converting Enzyme Inhibitors; Animals; Dose-Response Relationship, Drug; Electrocardiography; Heart Function Tests; Hemodynamics; Iridoid Glucosides; Iridoids; Isoproterenol; Male; Myocardial Infarction; Olea; Plant Roots; Rats; Rats, Wistar; Vasodilator Agents; Ventricular Remodeling

Stem cell transplantation has been widely acknowledged for their immense potential in regenerative medicine. In these procedures, the implanted cells need to maintain both their viability and functional properties for effective therapeutic outcomes. This has long been a subject of major concern and intensive studies. Microencapsulation of stem cells within polymeric microcapsules can be an efficient approach to achieve this goal, particularly for heart diseases. This study reports the use of biocompatible, fluorogenic genipin-cross-linked alginate chitosan (GCAC) microcapsules in delivery of human adipose stem cells (hASCs) with an aim to increase the implant retention in the infarcted myocardium for maximum clinical benefits. In vitro results show, under hypoxic conditions, the microencapsulated cells overexpressed significantly higher amount of biologically active vascular endothelial growth factor (VEGF). We investigated on the in vivo potential using immunocompetent female rats after induction of myocardial infarction. For this, animal groups (n = 8) received empty control microcapsules, 1.5 × 10(6) free male hASCs, or 1.5 × 10(6) microencapsulated male hASCs. Results show significant retention (3.5 times higher) of microencapsulated hASCs compared to free hASCs after 10 weeks of transplantation. Microencapsulated hASCs showed significantly attenuated infarct size compared to free hASCs and empty microcapsule group (21.6% ± 1.1% vs. 27.2% ± 3.1% vs. 33.3% ± 3.2%; p < 0.05), enhanced vasculogenesis, and improved cardiac function (fractional shortening: 24.2% ± 2.1% vs. 19.1% ± 0.5% vs. 12.0% ± 4.0%; p < 0.05). These data suggest that microencapsulated hASCs can contribute significantly to the improvement in cardiac functions. Their greater retentions exhibit reduced fibrosis and cardiac dysfunction in experimental animals. However, further research is needed to fully comprehend the underlying biological and immunological effects of microencapsulated hASCs, which jointly play important roles in cardiac repair.

Topics: Adipocytes; Alginates; Animals; Cell Differentiation; Cells, Cultured; Chitosan; Coronary Vessels; Disease Models, Animal; Female; Glucuronic Acid; Hexuronic Acids; Humans; Iridoids; Male; Myocardial Infarction; Myocardium; Neovascularization, Pathologic; Rats; Rats, Inbred Lew; Regenerative Medicine; Stem Cell Transplantation; Stem Cells; Vascular Endothelial Growth Factor A

Angiogenic therapies may need to select a stable agent to be delivered. In the study, a nonpeptide angiogenic agent, ginsenoside Rg(1) (Rg(1)), was encapsulated in the gelatin microspheres (MSs) crosslinked with genipin and intramuscularly injected into a rat model with infarcted myocardium. bFGF was used as a control. After swelling in an aqueous environment, the MSs without crosslinking became collapsed and stuck together. For those crosslinked, the swollen MSs appeared to be more stable with an increasing the degree of crosslinking. After it was released from MSs in vitro, the remaining activity of bFGF on HUVEC proliferation reduced significantly, while that of Rg(1) remained constant. An inspection of the retrieved hearts revealed a large aneurysmal left ventricle (LV) with a thinned myocardium and a significant myocardial fibrosis for that treated with the Empty MSs (without drug encapsulation). However, those receiving the MSs encapsulated with bFGF or Rg(1) attenuated the enlargement of the LV cavity and the development of myocardial fibrosis. The densities of microvessels found in the border zones of the infarct treated with the bFGF or Rg(1) MSs were significantly greater than that treated with the Empty MSs. These results indicated that Rg(1), a stable angiogenic agent, successfully enhanced the myocardial perfusion and preserved the infarcted LV function.

Topics: Angiogenesis Inducing Agents; Animals; Cell Proliferation; Cells, Cultured; Chemistry, Pharmaceutical; Coronary Circulation; Cross-Linking Reagents; Disease Models, Animal; Drug Carriers; Drug Compounding; Endothelial Cells; Feasibility Studies; Fibroblast Growth Factor 2; Fibrosis; Gelatin; Ginsenosides; Humans; Injections, Intramuscular; Iridoid Glycosides; Iridoids; Male; Microspheres; Myocardial Infarction; Neovascularization, Physiologic; Particle Size; Rats; Rats, Sprague-Dawley; Solubility; Time Factors; Ventricular Function, Left; Ventricular Remodeling