Standardized Chinese Formula Xin-Ke-Shu inhibits the myocardium Ca(2+) overloading and metabolic alternations in isoproterenol-induced myocardial infarction rats

Xinkeshu formula restrains pathological cardiac hypertrophy through metabolic remodeling via AMPK/mTOR pathway

BACKGROUND

Xinkeshu (XKS) formula is a patented traditional Chinese medicine used to treat cardiovascular diseases for decades. However, little is known about its potential influence on heart metabolism under pathological conditions.

PURPOSE

This study sought to explore the potential role of XKS in pathological cardiac hypertrophy, with a focus on metabolic remolding.

METHODS

We established pathological cardiac models in mice by transverse aortic constriction (TAC) and isoprenaline (ISO) challenge with continuous oral administration of XKS at specified doses for 4 weeks. In cultured cardiomyocytes, we observed the effects on metabolism and the mechanisms that underlie the process.

RESULTS

In the TAC model mice, oral administration of XKS restrained cardiac hypertrophy, indicated by decreases in heart mass and cardiomyocyte size. Meanwhile, XKS also suppressed fetal gene induction and cardiac fibrotic response. Echocardiography examination showed that XKS improved heart contractility and diastolic function. Similar results were observed in the hearts of mice subjected to isoprenaline challenge. In cultured cardiomyocytes, angiotensin II stimulation induced cardiomyocytes enlargement and fetal gene induction, which were normalized by XKS. XKS reduced cellular energy charge to induce AMPK activation, which inactivated mTOR by modification of phosphorylation, contributing to attenuating cardiac hypertrophy. Following cardiac hypertrophy, metabolism was reprogrammed, whereas augmented glycolysis and mitochondrial oxidation were reduced by XKS. As result of mTOR suppression, XKS reduced HIF-1α accumulation and blocked HIF-1α nuclear translocation, and thus reduced angiogenesis by downregulating Vegf gene expression.

CONCLUSION

These results show that XKS modulated metabolic remodeling through the AMPK/mTOR cascade to restrain pathological cardiac hypertrophy. Our findings shed new light on the role of XKS in cardiac protection, particularly in the context of metabolic remodeling.

Abnormal fatty acid metabolism and ceramide expression may discriminate myocardial infarction from strangulation death: A pilot study

Determining myocardial infarction (MI) and mechanical asphyxia (MA) was one of the most challenging tasks in forensic practice. The present study aimed to investigate the potential of fatty acid (FAs) metabolism, and lipid alterations in determining MI and MA. MA and MI mouse models were constructed, and metabolic profiles were obtained by LC-MS-based untargeted metabolomics. The metabolic alterations were explored using the PCA, OPLS-DA, the Wilcoxon test, and fold change analysis. The contents of lipid droplets (LDs) were detected by the transmission scanning electron microscope and Oil red O staining. The immunohistochemical assay was performed to detect CD36 and dysferlin. The ceramide was assessed by LC-MS. PCA showed considerable differences in the metabolite profiles, and the well-fitting OPLS-DA model was developed to screen differential metabolites. Thereinto, 9 metabolites in the MA were reduced, while metabolites were up- and down-regulated in MI. The increased CD36 suggested that MI and MA could enhance the intake of FAs and disturb energy metabolism. The increased LDs, decreased dysferlin, and increased ceramide (C18:0, C22:0, and C24:0) were observed in MI groups, confirming the lipid deposition. The present study indicated significant differences in myocardial FAs metabolism and lipid alterations between MI and MA, suggesting that FAs metabolism and related proteins, certain ceramide may harbor the potential as biomarkers for discrimination of MI and MA.

Effects of Xinkeshu tablets on coronary heart disease patients combined with anxiety and depression symptoms after percutaneous coronary intervention: A meta-analysis

BACKGROUND

Xinkeshu tablets (XKS), a well-known Chinese patent drug, have been administered to coronary heart disease (CHD) patients with anxiety and depression after percutaneous coronary intervention (PCI).

PURPOSE

This meta-analysis aimed to systematically evaluate the clinical effects of XKS for treating CHD patients with anxiety and depression after PCI.

METHODS

Randomized controlled trials (RCTs) about XKS alone or combined with conventional drugs for the treatment of CHD patients with anxiety and depression after PCI were retrieved from 7 databases (MEDLINE, EMBASE, the Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Database (VIP) Database, Chinese Biomedical Database (CBM) and Wanfang Database) through November 2021. First, the studies were reviewed and screened by two independent assessors according to the eligibility criteria. Second, the methodological quality of the eligible studies was evaluated based on the Cochrane Collaboration's tool for assessing the risk of bias. Subsequently, meta-analysis was performed by using RevMan 5.4 software, and publication bias was evaluated by Stata 12.0 software. Finally, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was applied to rate the quality of the evidence.

RESULTS

In total, 11 clinical RCTs involving 1000 patients were included in this study. This meta-analysis found that compared with conventional treatment alone, XKS combined with conventional treatment significantly improved the anxiety scale scores (SMD = -1.97, 95% CI -3.13 to -0.82; p = 0.0008; I2 = 98%), the depression scores (SMD = -2.80, 95% CI -4.49 to -1.10; p = 0.001; I2 = 98%), the scores on the Medical Outcomes Study 36 Item Short Form Health Survey (SF36) (MD = 11.22, 95% CI 4.19 to 18.26; p =0.002; I2 = 95%) and the blood lipid levels of total cholesterol (TC) (MD = -0.38, 95% CI -0.62 to -0.13; p = 0.003; I2 = 0%) and triglyceride (TG) (MD = -0.31, 95% CI -0.46 to -0.17; p < 0.0001; I2 =  0%).

CONCLUSION

The current evidence suggests that XKS might benefit CHD patients experiencing anxiety and depression after PCI by helping to improve their depression symptoms, TC and TG blood lipid levels. However, due to insufficient methodological quality of the studies, several risks of bias and inadequate reporting of the clinical data, more rigorous, multicenter, sufficient-sample and double-blind randomized clinical trials are warranted.

Effects of Puerarin on the Prevention and Treatment of Cardiovascular Diseases

Puerarin, an isoflavone glycoside derived from Pueraria lobata (Willd.) Ohwi, has been identified as a pharmacologically active component with diverse benefits. A large number of experimental and clinical studies have demonstrated that puerarin is widely used in the treatment of a variety of diseases. Among them, cardiovascular diseases (CVDs) are the leading cause of death in the world, and therefore remain one of the most prominent global public health concerns. In this review, we systematically analyze the preclinical investigations of puerarin in CVDs, such as atherosclerosis, cardiac hypertrophy, heart failure, diabetic cardiovascular complications, myocardial infarction, stroke and hypertension. In addition, the potential molecular targets of puerarin are also discussed. Furthermore, we summarize the clinical trails of puerarin in the treatment of CVDs. Finally, the therapeutic effects of puerarin derivatives and its drug delivery systems are overviewed.

Salvia miltiorrhiza and Pueraria lobata, two eminent herbs in Xin-Ke-Shu, ameliorate myocardial ischemia partially by modulating the accumulation of free fatty acids in rats

BACKGROUND

Xin-Ke-Shu (XKS), a commonly used traditional Chinese medicine, has been clinically proven to be effective for treatment of acute myocardial ischemia (AMI). Numerous studies underscore the important role of fatty acid metabolism in the pathogenesis of AMI.

PURPOSE

This study examined the relationship between free fatty acids (FFAs) and AMI and the contributions of individual herbs found in XKS to provide a basis for the study of the compatible principle of XKS.

METHODS

UFLC-MS/MS-based targeted metabolomics was performed to analyze the levels of 15 FFAs in the plasma and myocardium of isoproterenol (ISO)-induced AMI rats treated with XKS and the subtracted prescriptions of XKS. Electrocardiogram data, H&E staining, biochemical analysis and western blotting were assayed to illustrate the cardioprotection of XKS and its subtracted prescription in AMI. Correlation analysis was used to reveal the relationship between the levels of FFAs and overexpressed proteins/biochemical enzymes.

RESULTS

We found aberrant fatty acid metabolism in AMI rats. In both plasma and myocardium, the concentrations of most of quantified FFAs were significantly altered, whereas the concentrations of stearic acid and behenic acid were similar between the control and AMI groups. Correlation analysis revealed that palmitic acid, oleic acid, linoleic acid and arachidonic acid were potentially the most relevant FFAs to inflammatory and apoptotic proteins and CK-MB. Moreover, XKS effectively alleviated pathological alterations, FFA metabolism abnormity, inflammation and apoptosis found in the myocardium of AMI rats. Notably, the removal of Salvia miltiorrhiza and Pueraria lobata from XKS resulted in markedly regulation loss of cardioprotection during AMI, especially mediation loss of FFA metabolism. The other three herbs of XKS also played a role in improving AMI.

CONCLUSION

Fatty acid metabolism aberrance occurred during AMI. S. miltiorrhiza and P. lobata play vital roles in the anti-inflammatory and anti-apoptotic action partially by regulating FFA levels. Our findings revealed potential novel clinical FFAs for predicting AMI and extended the insights into the compatible principle of XKS in which S. miltiorrhiza and P. lobata can potently modulate FFA metabolism.

Therapeutic Effects of Traditional Chinese Medicine on Cardiovascular Diseases: the Central Role of Calcium Signaling

Calcium, as a second messenger, plays an important role in the pathogenesis of cardiovascular diseases (CVDs). The malfunction of calcium signaling in endothelial cells and vascular smooth muscle cells promotes hypertension. In cardiomyocytes, calcium overload induces apoptosis, leading to myocardial infarction and arrhythmias. Moreover, the calcium–calcineurin–nuclear factor of activated T cells (NFAT) pathway is essential for expressing the cardiac pro-hypertrophic gene. Heart failure is also characterized by reduced calcium transient amplitude and enhanced sarcoplasmic reticulum (SR) calcium leakage. Traditional Chinese medicine (TCM) has been used to treat CVDs for thousands of years in China. Because of its multicomponent and multitarget characteristics, TCM's unique advantages in CVD treatment are closely related to the modulation of multiple calcium handling proteins and calcium signaling pathways in different types of cells involved in distinct CVDs. Thus, we systematically review the diverse mechanisms of TCM in regulating calcium pathways to treat various types of CVDs, ranging from hypertrophic cardiomyopathy to diabetic heart disease.

A Review on Phytochemistry, Pharmacological Action, Ethanobotanical Uses and Nutritional Potential of Kedrostis foetidissima (Jacq.) Cogn

Nature is an amazing source for food, shelter, clothing and medicine. An impressive number of modern drugs are isolated from many sources like plants, animals and microbes. The development of natural products from traditional medicines is of great importance to society. Modern concepts and methodologies with abundant clinical studies, unique diversity of chemical structures and biological activities aid the modern drug discovery process. Kedrostis foetidissima (Jacq.) Cogn., a traditional medicinal plant of the Cucurbitaceae family, is found in India, Sri Lanka, Ethiopia and Western Malaysia. Almost all parts of the plant are used in traditional systems of medicines and reported having medicinal properties in both in vitro and in vivo studies. In the last few years, extensive research work had been carried out using extracts and isolated phytoconstituents from Kedrostis foetidissima to confirm its pharmacology and biological activities. Many scientific reports show that crude extracts and extensive numbers of phytochemical constituents isolated from Kedrostis foetidissima have activities like antimicrobial, antioxidant, anticancer, gastroprotective, anti-inflammatory and various other important medicinal properties. The therapeutic properties of the plants are mainly attributed to the existence of phytoconstituents like phenols, alkaloids, flavonoids, tannins, terpenoids and steroids. This comprehensive review in various aspects gave a brief overview of phytoconstituents, nutritional values and medicinal property of the plant and might attract the researchers to explore its medicinal activity by discovering novel biologically active compounds that can serve as a lead compound in pharmaceutical and food industry.

Role of sodium tetraborate as a cardioprotective or competitive agent: Modulation of hypertrophic intracellular signals

Boron is an essential trace element in cellular metabolism; however, the molecular mechanism of boron in the heart is unclear. In this study, we examined the effect of sodium tetraborate (as boron source) as a possible protective agent or competitive inhibitor of cardiac hypertrophy in an in vitro murine model. We evaluated different previously reported sodium tetraborate concentrations and it was found that 13 μM improves viability without affecting the cellular structure. We demonstrated that cardiomyocytes pretreated with sodium tetraborate prevents cellular damage induced by isoproterenol (cardioprotective effect) by increasing proliferation rate and inhibiting apoptosis. In addition, the reduction of the expression of the α1AR and β1AR adrenergic receptors as well as Erk1/2 was notable. Consequently, the expression of the early response genes c-myc, c-fos and c-jun was delayed. Also, the expression of GATA-4, NFAT, NKx2.5 and myogenin transcription factors involved in sarcomere synthesis declined. In contrast, cardiomyocytes, when treated simultaneously with sodium tetraborate and isoproterenol, did not increase their size (cytoplasmic gain), but an increase in apoptosis levels was observed; therefore, the proliferation rate was reduced. Although the mRNA levels of α1AR and β1AR as well as Erk1/2 and Akt1 were low at 24 h, their expression increased to 48 h. Notably, the mRNA of expression levels of c-myc, c-fos and c-jun were lower than those determined in the control, while the transcription factors GATA-4, MEF2c, Nkx2.5, NFAT and CDk9 were determined in most cells. These results suggest that pretreatment with sodium tetraborate in cardiomyocytes inhibits the hypertrophic effect. However, sodium tetraborate attenuates isoproterenol induced hypertrophy damage in cardiomyocytes when these two compounds are added simultaneously.

Oleic Acid Prevents Isoprenaline-Induced Cardiac Injury: Effects on Cellular Oxidative Stress, Inflammation and Histopathological Alterations

The present study was designed to assess the cardio-protective role of oleic acid in myocardial injury (MI) induced by intra-peritoneal injection of isoprenaline (ISO) in rats for 2 consecutive days. Oleic acid (OA) was administered orally (@ 5 mg/kg b.wt and 10 mg/kg b.wt) for 21 days before inducing MI. Pre-exposure to OA at higher dose significantly improved the HW/BW ratio, myocardial infarct size, lipid profiles (total cholesterol, HDL-C) and cardiac injury biomarkers (LDH, CK-MB, cardiac troponin-I, MMP-9), thus suggesting its cardio-protective role. The ameliorative potential of the higher dose of OA was further substantiated by its ability to reduce the cardiac oxidative stress as evidenced by significant decrease in lipid peroxidation coupled with increase in superoxide dismutase activity and reduced glutathione level. Significant decrease in heart rate as well as increase in RR and QT intervals in oleic acid pre-exposed rats were also observed. OA pre-treatment also reduced the histopathological alterations seen in myocardial injury group rats. The mRNA expression of cardiac UCP-2 gene, a regulator of reactive oxygen species (ROS) generation, was significantly increased in oleic acid pre-exposure group compared to the ISO-induced myocardial injury group. Thus increase in expression of UCP-2 gene in cardiac tissue seems to be one of the protective measures against myocardial injury. Based on the above findings, it may be inferred that oleic acid possesses promising cardio-protective potential against myocardial injury due to its anti-oxidative property and ability to modulate cardiac metabolic processes.

Neuroprotective Effect of Cyperi rhizome against Corticosterone-Induced PC12 Cell Injury via Suppression of Ca2+ Overloading

Cyperi Rhizoma (CR) is a well-known functional food and traditional herbal medicine in Asian countries for the treatment of menstrual or emotional disturbances in women. Recent studies have shown the pharmacological effects of CR on neuronal diseases, such as Parkinson’s disease (PD) and depression. Thus, the neuroprotective effect of CR might play a vital role in exerting its effect. Here, corticosterone-induced PC12 cells were applied to screen the active fraction of CR and evaluate its neuroprotective effect. The results indicated that the fraction containing medium-polarity chemical constituents (CR-50E) displayed the best protection effect. CR-50E could increase the cell viability and reduce cell apoptosis through inhibiting oxidative stress and decreasing the lactate dehydrogenase LDH release induced by corticosterone. Further, the mechanism of action was explored by cell metabolomics. The result showed CR-50E mediated the sphingolipids metabolism of corticosterone-induced PC12 cells, which suggested inhibition of Ca²⁺ overloading may involve the protection of CR-50E against cell damage. The expression levels of three key proteins in calcium transport, including phospholipase A2 (PLA2), calcium/calmodulin independent protein kinase II (CaMK II), and caspase-3, confirmed the above result by Western blot. The findings suggest that CR-50E can suppress the disequilibrium of calcium homeostasis-mediated apoptosis by improving the abnormal sphingolipids metabolism as well as remedying the damage of the cell membrane.

Application of metabolomics for unveiling the therapeutic role of traditional Chinese medicine in metabolic diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional medicine has been practiced for thousands of years in China and some Asian countries. Traditional Chinese Medicine (TCM) is characterized as multi-component and multiple targets in disease therapy, and it is a great challenge for elucidating the mechanisms of TCM.

AIM OF THE REVIEW

Comprehensively summarize the application of metabolomics in biomarker discovery, stratification of TCM syndromes, and mechanism underlying TCM therapy on metabolic diseases.

METHODS

This review systemically searched the publications with key words such as metabolomics, traditional Chinese medicine, metabolic diseases, obesity, cardiovascular disease, diabetes mellitus in "Title OR Abstract" in major databases including PubMed, the Web of Science, Google Scholar, Science Direct, CNKI from 2010 to 2019.

RESULTS

A total of 135 papers was searched and included in this review. An overview of articles indicated that metabolic characteristics may be a hallmark of different syndromes/models of metabolic diseases, which provides a new perspective for disease diagnosis and therapeutic optimization. Moreover, TCM treatment has significantly altered the metabolic perturbations associated with metabolic diseases, which may be an important mechanism for the therapeutic effect of TCM.

CONCLUSIONS

Until now, many metabolites and differential biomarkers related to the pathogenesis of metabolic diseases and TCM therapy have been discovered through metabolomics research. Unfortunately, the biological role and mechanism of disease-related metabolites were largely unclarified so far, which warrants further investigation.

Cecal Gut Microbiota and Metabolites Might Contribute to the Severity of Acute Myocardial Ischemia by Impacting the Intestinal Permeability, Oxidative Stress, and Energy Metabolism

Emerging evidence highlights the role of gut microbiota in regulating the pathogenesis of coronary heart disease. Here, we performed 16S rRNA gene sequencing and UPLC-Q-TOF/MS-based metabolomics to investigate the gut microbiome and metabolomes of cecal contents in the isoproterenol (ISO)-induced acute myocardial ischemia (AMI) rats. As expected, considerable gut microbiota alterations were observed in the AMI rats compared with the control rats, paralleling with intestinal inflammation and apoptosis. At phylum level, the abundance of Firmicutes was significantly decreased, whereas the abundance of Bacteroidetes and Spirochaetae was strikingly enriched in the AMI group. At genus level, the significant alteration of genera Treponema 2, Rikenellaceae RC9 gut group, Prevotellaceae UCG-003, and Bacteroides may contribute to the pathogenesis of AMI. These altered microbiota might influence the intestinal permeability and subsequently impair intestinal barrier and stimulate gut inflammation. Consistently, significantly metabolic differences of cecal contents between the AMI and control groups were revealed, and threonic acid, L-urobilin and L-urobilinogen were considered the most associated cecal metabolites with AMI. These strikingly altered metabolites were mainly related to energy metabolism and oxidative stress which could lead to apoptosis and further affect gut barrier. Ultimately, we revealed the potential link of these altered gut microbiota/metabolomes and intestinal inflammatory factors and apoptotic proteins and further confirmed their intimate connections with intestinal inflammation and gut barrier. Our findings depict uncovered potential relationship among the gut microbiome, cecal metabolomes and AMI.

Protective effect of omeprazole and lansoprazole on β-receptor stimulated myocardial infarction in Wistar rats

We investigated the effect of omeprazole (OPZ) and lansoprazole (LPZ) on the pathophysiology of myocardial necrosis in rats by inspecting a series of indicators like hemodynamic parameters, biochemical estimations and histopathological changes in the myocardial tissue. Rats received either OPZ, LPZ (50 mg/kg/day, p.o.) individually for 7 days with concurrent administration of isoproterenol (ISO) (150 mg/kg, s.c.) on 6th and 7th day of study period to induce myocardial infarction. On the 8th day after measuring hemodynamic parameters, rats were killed and parameters were evaluated. ECG waves were found to be normal in the treatment group. ISO control rats revealed escalation in the oxidative stress as evidenced by depletion in the content of SOD, GSH, catalase and increase in the level of MDA and NO as compared with the normal rats. Treatment with OPZ and LPZ significantly reduced the ROS, indicated by an increase in the endogenous antioxidants and a decrease in NO and MDA levels. ISO control rats showed a significant elevation in the levels of pro-inflammatory cytokine TNF-α as compared to the normal and treatment group of rats. Administration of OPZ and LPZ does not exhibit any significant toxicity. Our findings reveal that multiple doses of OPZ and LPZ may have distinctly minimized the ISO-induced myocardial necrosis by declining the hmodynamic parameters, oxidative stress and pro-inflammatory cytokine TNF-α in myocardial infarcted rats.

Cardioprotective Effects of Puerarin-V on Isoproterenol-Induced Myocardial Infarction Mice Is Associated with Regulation of PPAR-Υ/NF-κB Pathway

Puerarin is a well-known traditional Chinese medicine which has been used for the treatment of cardiovascular diseases. Recently, a new advantageous crystal form of puerarin, puerarin-V, has been developed. However, the cardioprotective effects of puerarin-V on myocardial infarction (MI) heart failure are still unclear. In this research, we aim to evaluate the cardioprotective effects of puerarin-V on the isoproterenol (ISO)-induced MI mice and elucidate the underlying mechanisms. To induce MI in C57BL/6 mice, ISO was administered at 40 mg/kg subcutaneously every 12 h for three times in total. The mice were randomly divided into nine groups: (1) control; (2) ISO; (3) ISO + puerarin injection; (4⁻9) ISO + puerarin-V at different doses and timings. After treatment, cardiac function was evaluated by electrocardiogram (ECG), biochemical and histochemical analysis. In vitro inflammatory responses and apoptosis were evaluated in human coronary artery endothelial cells (HCAECs) challenged by lipopolysaccharide (LPS). LPS-induced PPAR-Υ/NF-κB and subsequently activation of cytokines were assessed by the western blot and real-time polymerase chain reaction (PCR). Administration of puerarin-V significantly inhibits the typical ST segment depression compared with that in MI mice. Further, puerarin-V treatment significantly improves ventricular wall infarction, decreases the incidence of mortality, and inhibits the levels of myocardial injury markers. Moreover, puerarin-V treatment reduces the inflammatory milieu in the heart of MI mice, thereby blocking the upregulation of proinflammatory cytokines (TNF-α, IL-1β and IL-6). The beneficial effects of puerarin-V might be associated with the normalization in gene expression of PPAR-Υ and PPAR-Υ/NF-κB /ΙκB-α/ΙΚΚα/β phosphorylation. In the in vitro experiment, treatment with puerarin-V (0.3, 1 and 3 μM) significantly reduces cell death and suppresses the inflammation cytokines expression. Likewise, puerarin-V exhibits similar mechanisms. The cardioprotective effects of puerarin-V treatment on MI mice in the pre + post-ISO group seem to be more prominent compared to those in the post-ISO group. Puerarin-V exerts cardioprotective effects against ISO-induced MI in mice, which may be related to the activation of PPAR-γ and the inhibition of NF-κB signaling in vivo and in vitro. Taken together, our research provides a new therapeutic option for the treatment of MI in clinic.

Calcium Sensing Receptor-Related Pathway Contributes to Cardiac Injury and the Mechanism of Astragaloside IV on Cardioprotection

Activation of calcium sensing receptor (CaSR) contributes to cardiac injury, but the underlying mechanism has not yet been examined. Astragaloside IV (AsIV) was previously reported to exhibit protective effects against various myocardial injuries. The aim of the present study was to investigate the underlying mechanism of CaSR in cardiac hypertrophy and apoptosis and to evaluate whether the protective effect of AsIV against myocardial injury is associated with CaSR and its related signaling pathway. In vivo and in vitro myocardial injury was induced by isoproterenol (Iso) or GdCl₃ (a CaSR agonist) in rats and heart H9C2 cells. Cardiac cell hypertrophy, apoptosis, function, Mitochondrial Membrane Potential (MMP), mitochondrial ultrastructure, and [Ca²⁺]_i, as well as the protein expression of CaSR, calcium/calmodulin-dependent protein kinase II (CaMKII), calcineurin (CaN), sarcoplasmic reticulum Ca²⁺-ATPase2a (SERCA2a), and the inositol 1,4,5-trisphosphate receptor (IP3R), were measured in vivo and/or in vitro. The results showed that AsIV attenuated cardiac hypertrophy and apoptosis and attenuated impairments in cardiac function, mitochondrial structure, and MMP induced by Iso or GdCl₃ in rat myocardial tissue and H9C2 cells. Importantly, AsIV treatment inhibited the enhancement of [Ca²⁺]_i and CaSR expression induced by Iso or GdCl₃, an effect similar to that of the CaSR antagonist NPS2143. In addition, AsIV treatment repressed CaSR, CaMKII, and CaN activation and inhibited NFAT-3 nuclear translocation. Mechanistic analysis using lentivirus infection showed that CaSR overexpression activated the CaMKII and CaN signaling pathways and that this response was enhanced by Iso. The results suggested that CaSR-mediated changes in [Ca²⁺]_i and CaMKII and CaN signaling pathways contribute to cardiac hypertrophy and apoptosis and are involved in the protective effect of astragaloside IV against cardiac injury.

Preventive effect of Agnucastoside C against Isoproterenol-induced myocardial injury

An iridoid glycoside, agnucastoside C (ACC) was isolated from the leaves of Moringa oliefera and its cardio protective potential was investigated in adult rats by examining the effects of this test compound, ACC at 30 mg/kg for 14 days in isoproterenol (100 mg/kg)-induced myocardial injury. Isoproterenol (ISO) administration induced the myocardial injury as evidenced by the altered ECG pattern with ST-segment elevation and an increase in the levels of cardiac injury markers including troponin-I, creatine kinase-MB, alanine transaminase, aspartate transaminase, lactate dehydrogenase; inflammatory markers, interleukine-6 and tumor necrosis factor. In this group, there was also an increase in cardiac lipid peroxidation and a decrease in cellular antioxidants. However, pretreatment with ACC maintained the normal ECG pattern and nearly normal levels of all the cardiac markers in ISO-induced animals. Electron microscopic and histological studies also showed marked reduction in ISO-induced cardiac damages including infarct size by ACC. Analysis by 2-DE revealed the involvement of 19 different cardiac proteins, associated with energy metabolism, oxidative stress and maintenance of cytoskeleton. The expression of those proteins were altered by ISO, but maintained in ACC pretreated rats. Our findings reveal the potential of isolated ACC in the prevention of myocardial damage.

Molecular understanding of the protective role of natural products on isoproterenol-induced myocardial infarction: A review

Modern medicine has been used to treat myocardial infarction, a subset of cardiovascular diseases, and have been relatively effective but not without adverse effects. Consequently, this issue has stimulated interest in the use of natural products, which may be equally effective and better tolerated. Many studies have investigated the cardioprotective effect of natural products, such as plant-derived phytochemicals, against isoproterenol (ISO)-induced myocardial damage; these have produced promising results on the basis of their antioxidant, anti-atherosclerotic, anti-apoptotic and anti-inflammatory activities. This review briefly introduces the pathophysiology of myocardial infarction (MI) and then addresses the progress of natural product research towards its treatment. We highlight the promising applications and mechanisms of action of plant extracts, phytochemicals and polyherbal formulations towards the treatment of ISO-induced myocardial damage. Most of the products displayed elevated antioxidant levels with decreased oxidative stress and lipid peroxidation, along with restoration of ionic balance and lowered expression of myocardial injury markers, pro-inflammatory cytokines, and apoptotic parameters. Likewise, lipid profiles were positively altered and histopathological improvements could be seen from, for example, the better membrane integrity, decreased necrosis, edema, infarct size, and leukocyte infiltration. This review highlights promising results towards the amelioration of ISO-induced myocardial damage, which suggest the direction for future research on natural products that could be used to treat MI.