The Role of Oxidative Stress in Myocardial Ischemia and Reperfusion Injury and Remodeling: Revisited

Aerobic interval training preconditioning protocols inhibit isoproterenol-induced pathological cardiac remodeling in rats: Implications on oxidative balance, autophagy, and apoptosis

This study aimed to investigate the potential cardioprotective effects of moderate and high-intensity aerobic interval training (MIIT and HIIT) preconditioning. The focus was on histological changes, pro-oxidant-antioxidant balance, autophagy initiation, and apoptosis in myocardial tissue incited by isoproterenol-induced pathological cardiac remodeling (ISO-induced PCR). Male Wistar rats were randomly divided into control (n ​= ​6), ISO (n ​= ​8), MIIT (n ​= ​4), HIIT (n ​= ​4), MIIT ​+ ​ISO (n ​= ​8), and HIIT ​+ ​ISO (n ​= ​8) groups. The MIIT and HIIT protocols were administered for 10 weeks, followed by the induction of cardiac remodeling using subcutaneous injection of ISO (100 ​mg/kg for two consecutive days). Alterations in heart rate (HR), mean arterial pressure (MAP), rate pressure product (RPP), myocardial oxygen consumption (MV ˙ O2), cardiac hypertrophy, histopathological changes, pro-oxidant-antioxidant balance, autophagy biomarkers (Beclin-1, Atg7, p62, LC3 I/II), and apoptotic cell distribution were measured. The findings revealed that the MIIT ​+ ​ISO and HIIT ​+ ​ISO groups demonstrated diminished myocardial damage, hemorrhage, immune cell infiltration, edema, necrosis, and apoptosis compared to ISO-induced rats. MIIT and HIIT preconditioning mitigated HR, enhanced MAP, and preserved MV ˙ O2 and RPP. The pro-oxidant-antioxidant balance was sustained in both MIIT ​+ ​ISO and HIIT ​+ ​ISO groups, with MIIT primarily inhibiting pro-apoptotic autophagy progression through maintaining pro-oxidant-antioxidant balance, and HIIT promoting pro-survival autophagy. The results demonstrated the beneficial effects of both MIIT and HIIT as AITs preconditioning in ameliorating ISO-induced PCR by improving exercise capacity, hemodynamic parameters, and histopathological changes. Some of these protective effects can be attributed to the modulation of cardiac apoptosis, autophagy, and oxidative stress.

Small Molecules Targeting Mitochondria: A Mechanistic Approach to Combating Doxorubicin-Induced Cardiotoxicity

Doxorubicin (Dox) is a commonly used chemotherapy drug effective against a range of cancers, but its clinical application is greatly limited by dose-dependent and cumulative cardiotoxicity. Mitochondrial dysfunction is recognized as a key factor in Dox-induced cardiotoxicity, leading to oxidative stress, disrupted calcium balance, and activation of apoptotic pathways. Recent research has emphasized the potential of small molecules that specifically target mitochondria to alleviate these harmful effects. This review provides a comprehensive analysis of small molecules that offer cardioprotection by preserving mitochondrial function in the context of doxorubicin-induced cardiotoxicity (DIC). The mechanisms of action include the reduction of reactive oxygen species (ROS) production, stabilization of mitochondrial membrane potential, enhancement of mitochondrial biogenesis, and modulation of key signaling pathways involved in cell survival and apoptosis. By targeting mitochondria, these small molecules present a promising therapeutic strategy to prevent or reduce the cardiotoxic effects associated with Dox treatment. This review not only discusses the mechanistic actions of these agents but also emphasizes their potential in improving cardiovascular outcomes for cancer patients. Gaining insight into these mechanisms can help in creating more effective strategies to safeguard the heart during chemotherapy, allowing for the ongoing use of Dox with a lower risk to the patient's cardiovascular health. This review highlights the critical role of mitochondria-targeted therapies as a promising approach in addressing DIC.

Longxuetongluo Capsule alleviate ischemia/reperfusion induced cardiomyocyte apoptosis through modulating oxidative stress and mitochondrial dysfunction

BACKGROUND

Chinese dragon's blood, the red resin of Dracaena cochinchinensis (Lour.) S. C. Chen., is widely used to treat cardiovascular and cerebrovascular diseases in China. Longxuetongluo Capsule (LTC) is a total phenolic compound extracted from Chinese dragon's blood, currently used in treating ischemic stroke. Myocardial injury can be aggravated after reperfusion of ischemic myocardium, which is called myocardial ischemia-reperfusion injury (MIRI), and the mechanism of MIRI is complex. However, the exact effect and mechanism of LTC on MIRI are still unclear. We explore the effect of LTC on alleviating MIRI based on mitochondrial dysfunction and oxidative stress.

AIM OF THE STUDY

To explore the cardioprotective mechanism of LTC against MIRI.

MATERIALS AND METHODS

A rat MIRI model was constructed through ligation of the left anterior descending coronary artery, and LTC was given continuously for 28 days before surgery. The H9c2 cardiomyocyte injury model was induced by oxygen-glucose deprivation/reperfusion (OGD/R), and LTC was given 24 h before OGD. Myocardial ischemia areas were detected with 2,3,5-triphenyltetrazolium chloride (TTC) staining. Cardiac histopathological changes were detected with hematoxylin-eosin (HE) staining. And biochemical indexes were detected with serum biochemical kit. Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) staining and flow cytometry were used to detect apoptosis. Fluorescent probes were used to observe reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), Ca2+and other indexes. MitoTracker staining and immunofluorescence were used to observe the morphology of mitochondria and translocation of dynamin-related protein 1 (Drp1). Finally, immunohistochemistry and Western blotting were used to examine the expression of proteins related to apoptosis, mitochondrial fission and fusion and oxidative stress.

RESULTS

LTC could ameliorate cardiac pathological changes, decrease myocardial infarct area and the content or level of relevant serum cardiac enzymes, indicating that LTC could alleviate MIRI. Meanwhile, LTC could inhibit cardiomyocyte apoptosis via regulating apoptosis-related protein expression, and it could restore mitochondrial morphology, maintain ΔΨm, inhibit mitochondrial ROS generation and Ca2+ accumulation, increase the expression of mitochondrial fusion protein 2 (Mfn2), decrease the level of phosphorylation dynamin-related protein 1 (p-Drp1), and regulate ATP synthesis, thereby significantly ameliorating mitochondrial dysfunction. Moreover, LTC significantly reduced the expression of NADPH oxidase 2 (NOX2), NADPH oxidase 4 (NOX4) and neutrophil cytosolic factor 2 (NOXA2/p67phox), and reduced ROS production.

CONCLUSION

The study demonstrated that LTC could inhibit MIRI induced cardiomyocyte apoptosis by inhibiting ROS generation and mitochondrial dysfunction, and these fundings suggested that LTC can be used to alleviate MIRI, which provides a potential therapeutic approach for future treatment of MIRI.

Treatment of Acute and Long-COVID, Diabetes, Myocardial Infarction, and Alzheimer's Disease: The Potential Role of a Novel Nano-Compound-The Transdermal Glutathione-Cyclodextrin Complex

Oxidative stress (OS) occurs from excessive reactive oxygen species or a deficiency of antioxidants-primarily endogenous glutathione (GSH). There are many illnesses, from acute and post-COVID-19, diabetes, myocardial infarction to Alzheimer's disease, that are associated with OS. These dissimilar illnesses are, in order, viral infections, metabolic disorders, ischemic events, and neurodegenerative disorders. Evidence is presented that in many illnesses, (1) OS is an early initiator and significant promotor of their progressive pathophysiologic processes, (2) early reduction of OS may prevent later serious and irreversible complications, (3) GSH deficiency is associated with OS, (4) GSH can likely reduce OS and restore adaptive physiology, (5) effective administration of GSH can be accomplished with a novel nano-product, the GSH/cyclodextrin (GC) complex. OS is an overlooked pathological process of many illnesses. Significantly, with the GSH/cyclodextrin (GC) complex, therapeutic administration of GSH is now available to reduce OS. Finally, rigorous prospective studies are needed to confirm the efficacy of this therapeutic approach.

Plasma metabolic profiling reveals that crude and processed Polygonatum cyrtonema hua extract ameliorates myocardial ischemia-induced damage by regulating branched-chain amino acid and energy metabolism

Polygonatum cyrtonema Hua and its processed products have demonstrated cardio-protective effects, though the underlying mechanisms remain unclear. In this study, plasma metabolic profiling and pattern recognition were employed to explore the cardio-protective mechanisms of both crude and processed P. cyrtonema in a myocardial ischemia model induced by ligation, using gas chromatography-mass spectrometry. Post-modeling, plasma levels of creatine kinase-MB, lactate dehydrogenase, troponin T, and malondialdehyde were significantly elevated but were notably reduced after treatment. Conversely, plasma levels of glutathione peroxidase and superoxide dismutase, which were significantly decreased post-modeling, were restored following treatment. Hematoxylin-eosin (HE) and Masson staining revealed that both crude and processed P. cyrtonema effectively reduced inflammatory infiltration and fibrosis in cardiac tissue. Metabolic profiling identified 34 differential endogenous metabolites in the treatment groups, with 19 confirmed using standard compounds. The linear correlation coefficients (R2) for these standards ranged from 0.9960 to 0.9996, indicating high accuracy. The method exhibited excellent precision and repeatability, with relative standard deviation (RSD) values below 8.57%. Recovery rates were between 95.02% and 105.15%, and the stability of the standard compounds was confirmed after three freeze-thaw cycles, with RSD values under 4.42%. Both crude and processed P. cyrtonema were found to alleviate myocardial ischemia symptoms by regulating branched-chain amino acid metabolism and energy metabolism. These findings provide a solid foundation for the potential clinical use of this herb and its processed products in treating heart disease.

Proteomics Profiling of Bilirubin Nanoparticle Treatment against Myocardial Ischemia-Reperfusion Injury

In myocardial infarction, ischemia-reperfusion injury (IRI) poses a significant challenge due to a lack of effective treatments. Bilirubin, a natural compound known for its anti-inflammatory and antioxidant properties, has been identified as a potential therapeutic agent for IRI. Currently, there are no reports about proteomic studies related to IRI and bilirubin treatment. In this study, we explored the effects of bilirubin nanoparticles in a rat model of myocardial IRI. A total of 3616 protein groups comprising 76,681 distinct peptides were identified using LC-MS/MS, where we distinguished two kinds of protein groups: those showing increased expression in IRI and decreased expression in IRI with bilirubin treatment, and vice versa, accounting for 202 and 35 proteins, respectively. Our proteomic analysis identified significant upregulation in the Wnt and insulin signaling pathways and increased Golgi markers, indicating their role in mediating bilirubin nanoparticle's protective effects. This research contributes to the proteomic understanding of myocardial IRI and suggests bilirubin nanoparticles as a promising strategy for cardiac protection, warranting further investigation in human models.

PKM2 regulates metabolic flux and oxidative stress in the murine heart

Cardiac metabolism ensures a continuous ATP supply, primarily using fatty acids in a healthy state and favoring glucose in pathological conditions. Pyruvate kinase muscle (PKM) controls the final step of glycolysis, with PKM1 being the main isoform in the heart. PKM2, elevated in various heart diseases, has been suggested to play a protective role in cardiac stress, but its function in basal cardiac metabolism remains unclear. We examined hearts from global PKM2 knockout (PKM2-/-) mice and found reduced intracellular glucose. Isotopic tracing of U-13C glucose revealed a shift to biosynthetic pathways in PKM2-/- cardiomyocytes. Total ATP content was two-thirds lower in PKM2-/- hearts, and functional analysis indicated reduced mitochondrial oxygen consumption. Total reactive oxygen species (ROS) and mitochondrial superoxide were also increased in PKM2-/- cardiomyocytes. Intriguingly, PKM2-/- hearts had preserved ejection fraction compared to controls. Mechanistically, increased calcium/calmodulin-dependent kinase II activity and phospholamban phosphorylation may contribute to higher sarcoendoplasmic reticulum calcium ATPase 2 pump activity in PKM2-/- hearts. Loss of PKM2 led to altered glucose metabolism, diminished mitochondrial function, and increased ROS in cardiomyocytes. These data suggest that cardiac PKM2 acts as an important rheostat to maintain ATP levels while limiting oxidative stress. Although loss of PKM2 did not impair baseline contractility, its absence may make hearts more sensitive to environmental stress or injury.

The application of extracorporeal shock wave therapy on stem cells therapy to treat various diseases

In the last ten years, stem cell (SC) therapy has been extensively used to treat a range of conditions such as degenerative illnesses, ischemia-related organ dysfunction, diabetes, and neurological disorders. However, the clinical application of these therapies is limited due to the poor survival and differentiation potential of stem cells (SCs). Extracorporeal shock wave therapy (ESWT), as a non-invasive therapy, has shown great application potential in enhancing the proliferation, differentiation, migration, and recruitment of stem cells, offering new possibilities for utilizing ESWT in conjunction with stem cells for the treatment of different systemic conditions. The review provides a detailed overview of the advances in using ESWT with SCs to treat musculoskeletal, cardiovascular, genitourinary, and nervous system conditions, suggesting that ESWT is a promising strategy for enhancing the efficacy of SC therapy for various diseases.

Safflower Yellow Injection Alleviates Myocardial Ischemia/Reperfusion Injury by Reducing Oxidative and Endoplasmic Reticulum Stress

Safflower yellow is an extract of the famous Chinese medicine Carthamus tinctorious L, and safflower yellow injection (SYI) is widely used clinically to treat angina pectoris. However, there are few studies on the anti-myocardial ischemia/reperfusion (I/R) injury effect of SYI, and its mechanisms are unclear. In the present study, we aimed to investigate the protective effect of SYI on myocardial I/R injury and explore its underlying mechanisms. Male Sprague Dawley rats were randomly divided into a control group, sham group, model group, and SYI group (20 mg/kg, femoral vein injection 1 h before modeling). The left anterior descending coronary artery was ligated to establish a myocardial I/R model. H9c2 cells were exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) after incubation with 80 μg/mL SYI for 24 h. In vivo, TsTC, HE, and TUNEL staining were performed to evaluate myocardial injury and apoptosis. A kit was used to detect superoxide dismutase (SOD) and malondialdehyde (MDA) to assess oxidative stress. In vitro, flow cytometry was used to detect the reactive oxygen species (ROS) content and apoptosis rate. Protein levels were determined via Western blotting. Pretreatment with SYI significantly reduced infarct size and pathological damage in rat hearts and suppressed cardiomyocyte apoptosis in vivo and in vitro. In addition, SYI inhibited oxidative stress by increasing SOD activity and decreasing MDA content and ROS production. Myocardial I/R and OGD/R activate endoplasmic reticulum (ER) stress, as evidenced by increased expression of activating transcription factor 6 (ATF6), glucose-regulated protein 78 (GRP78), cysteinyl aspartate-specific proteinase caspase-12, and C/EBP-homologous protein (CHOP), which were all inhibited by SYI. SYI ameliorated myocardial I/R injury by attenuating apoptosis, oxidative damage, and ER stress, which revealed new mechanistic insights into its application.

A Proof of Principle 2D Spatial Proteome Mapping Analysis Reveals Distinct Regional Differences in the Cardiac Proteome

Proteomics studies often explore phenotypic differences between whole organs and systems. Within the heart, more subtle variation exists. To date, differences in the underlying proteome are only described between whole cardiac chambers. This study, using the bovine heart as a model, investigates inter-regional differences and assesses the feasibility of measuring detailed, cross-tissue variance in the cardiac proteome. Using a bovine heart, we created a two-dimensional section through a plane going through two chambers. This plane was further sectioned into 4 × 4 mm cubes and analysed using label-free proteomics. We identified three distinct proteomes. When mapped to the extracted sections, the proteomes corresponded largely to the outer wall of the right ventricle and secondly to the outer wall of the left ventricle, right atrial appendage, tricuspid and mitral valves, modulator band, and parts of the left atrium. The third separate proteome corresponded to the inner walls of the left and right ventricles, septum, and left atrial appendage. Differential protein abundancies indicated differences in energy metabolism between regions. Data analyses of the mitochondrial proteins revealed a variable pattern of abundances of complexes I-V between the proteomes, indicating differences in the bioenergetics of the different cardiac sub-proteomes. Mapping of disease-associated proteins interestingly showed desmoglein-2, for which defects in this protein are known to cause Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy, which was present predominantly in the outer wall of the left ventricle. This study highlights that organs can have variable proteomes that do not necessarily correspond to anatomical features.

A Systematic Review on Advances in Management of Oxidative Stress-Associated Cardiovascular Diseases

Oxidative stress plays a significant role in the pathogenesis of cardiovascular diseases, such as myocardial ischemia/reperfusion injury, atherosclerosis, heart failure, and hypertension. This systematic review aims to integrate most relevant studies on oxidative stress management in cardiovascular diseases. We searched relevant literatures in the PubMed database using specific keywords. We put emphasis on those manuscripts that were published more recently and in higher impact journals. We reviewed a total of 200 articles. We examined current oxidative stress managements in cardiovascular diseases, including supplements like resveratrol, vitamins C and E, omega-3 fatty acids, flavonoids, and coenzyme-10, which have shown antioxidative properties and potential cardiovascular benefits. In addition, we reviewed the pharmacological treatments including newly discovered antioxidants and nanoparticles that show potential effects in targeting the specific oxidative stress pathways. Lastly, we examined biomarkers, such as soluble transferrin receptor, transthyretin, and cystatin C in evaluating antioxidant status and identifying cardiovascular risk. By addressing oxidative stress management and mechanisms, this paper emphasizes the importance of maintaining the balance between oxidants and antioxidants in the progression of cardiovascular diseases. This review paper is registered with the International Platform of Registered Systematic Review and Meta-analysis Protocols (INPLASY), registration # INPLASY202470064.

Insight into the cardioprotective effects of melatonin: shining a spotlight on intercellular Sirt signaling communication

Cardiovascular diseases (CVDs) are the leading causes of death and illness worldwide. While there have been advancements in the treatment of CVDs using medication and medical procedures, these conventional methods have limited effectiveness in halting the progression of heart diseases to complete heart failure. However, in recent years, the hormone melatonin has shown promise as a protective agent for the heart. Melatonin, which is secreted by the pineal gland and regulates our sleep-wake cycle, plays a role in various biological processes including oxidative stress, mitochondrial function, and cell death. The Sirtuin (Sirt) family of proteins has gained attention for their involvement in many cellular functions related to heart health. It has been well established that melatonin activates the Sirt signaling pathways, leading to several beneficial effects on the heart. These include preserving mitochondrial function, reducing oxidative stress, decreasing inflammation, preventing cell death, and regulating autophagy in cardiac cells. Therefore, melatonin could play crucial roles in ameliorating various cardiovascular pathologies, such as sepsis, drug toxicity-induced myocardial injury, myocardial ischemia-reperfusion injury, hypertension, heart failure, and diabetic cardiomyopathy. These effects may be partly attributed to the modulation of different Sirt family members by melatonin. This review summarizes the existing body of literature highlighting the cardioprotective effects of melatonin, specifically the ones including modulation of Sirt signaling pathways. Also, we discuss the potential use of melatonin-Sirt interactions as a forthcoming therapeutic target for managing and preventing CVDs.

Cardioprotective effects of the aqueous extract of Echinops cephalotes on myocardial ischemia-reperfusion in rats by modulation of MMP-2, MMP-9, TIMP, and oxidative stress

Echinops plants have received great attention for the treatment of many diseases due to pharmacological properties such as their antidiabetic, antioxidant, and anti-inflammatory characteristics. The major purpose of the present study was to investigate the cardioprotective benefits of Echinops cephalotes (Ech) against myocardial ischemia-reperfusion (MI/R) injury. Male Wistar rats were randomly allocated to three groups: sham, MI, and MI + Ech. The left coronary artery (LAD) was blocked for 30 minutes to induce MI. In the treatment group, rats were given 150 mg/kg/day of Ech extract for 28 days. Aqueous extracts were made from Echinops plants. To study heart function, fibrosis, cardiac damage indicators, and oxidative stress factors, echocardiography, Masson's trichrome staining, and biochemical tests were used. The expression of matrix metalloproteinase 2 and 9 (MMP2 and MMP-9) and tissue inhibitor of metalloproteinase (TIMP) was determined using Western blotting. Tissue damage was assessed using hematoxylin and eosin staining. MI group exhibited significantly reduced ejection fraction (EF) and fractional shortening (FS), enhanced levels of lactate dehydrogenase (LDH), creatine kinase MB (CK-MB), cardiac Troponin I (cTnI), and malondialdehyde (MDA), as well as a decrease in the Glutathione (GSH) tissue content, reduced activity of superoxide dismutase (SOD), increasing fibrosis, upregulations of MMP-2 and MMP-9, and reduction of TIMP compared to the sham group. The findings suggest that Ech in particular, could be a promising therapeutic agent to reduce the damage in MI by targeting oxidative stress and modulating the activities of matrix metalloproteinases and their tissue inhibitors.

Management of ROS and Regulatory Cell Death in Myocardial Ischemia-Reperfusion Injury

Myocardial ischemia-reperfusion injury (MIRI) is fatal to patients, leading to cardiomyocyte death and myocardial remodeling. Reactive oxygen species (ROS) and oxidative stress play important roles in MIRI. There is a complex crosstalk between ROS and regulatory cell deaths (RCD) in cardiomyocytes, such as apoptosis, pyroptosis, autophagy, and ferroptosis. ROS is a double-edged sword. A reasonable level of ROS maintains the normal physiological activity of myocardial cells. However, during myocardial ischemia-reperfusion, excessive ROS generation accelerates myocardial damage through a variety of biological pathways. ROS regulates cardiomyocyte RCD through various molecular mechanisms. Targeting the removal of excess ROS has been considered an effective way to reverse myocardial damage. Many studies have applied antioxidant drugs or new advanced materials to reduce ROS levels to alleviate MIRI. Although the road from laboratory to clinic has been difficult, many scholars still persevere. This article reviews the molecular mechanisms of ROS inhibition to regulate cardiomyocyte RCD, with a view to providing new insights into prevention and treatment strategies for MIRI.

Proteomic Analysis and Sex-Specific Changes in Chronically Ischemic Swine Myocardium Treated with Sodium-Glucose Cotransporter-2 Inhibitor Canagliflozin

BACKGROUND

Although sodium-glucose cotransporter-2 inhibitors have been shown to improve cardiovascular outcomes in general, little is presently known about any sex-specific changes that may result from this therapy. We sought to investigate and quantify potential sex-specific changes seen with the sodium-glucose cotransporter-2 inhibitor canagliflozin (CAN) in a swine model of chronic myocardial ischemia.

STUDY DESIGN

Eighteen Yorkshire swine underwent left thoracotomy with placement of an ameroid constrictor. Two weeks postop, swine were assigned to receive either control (F = 5 and M = 5) or CAN 300 mg daily (F = 4 and M = 4). After 5 weeks of therapy, swine underwent myocardial functional measurements, and myocardial tissue was sent for proteomic analysis.

RESULTS

Functional measurements showed increased cardiac output, stroke volume, ejection fraction, and ischemic myocardial flow at rest in male swine treated with CAN compared with control male swine (all p < 0.05). The female swine treated with CAN had no change in cardiac function as compared with control female swine. Proteomic analysis demonstrated 6 upregulated and 97 downregulated proteins in the CAN female group compared with the control female group. Pathway analysis showed decreases in proteins in the tricarboxylic acidic cycle. The CAN male group had 639 upregulated and 172 downregulated proteins compared with control male group. Pathway analysis showed increases in pathways related to cellular metabolism and decreases in pathways relevant to the development of cardiomyopathy and to oxidative phosphorylation.

CONCLUSIONS

Male swine treated with CAN had significant improvements in cardiac function that were not observed in female swine treated with CAN. Moreover, CAN treatment in male swine was associated with significantly more changes in protein expression than in female swine treated with CAN. The increased proteomic changes seen in the CAN male group likely contributed to the more robust changes in cardiac function seen in male swine treated with CAN.

Small extracellular vesicle-mediated CRISPR-Cas9 RNP delivery for cardiac-specific genome editing

Myocardial infarction (MI) is a major cause of morbidity and mortality worldwide. Although clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) gene editing holds immense potential for genetic manipulation, its clinical application is hindered by the absence of an efficient heart-targeted drug delivery system. Herein, we developed CRISPR-Cas9 ribonucleoprotein (RNP)-loaded extracellular vesicles (EVs) conjugated with cardiac-targeting peptide (T) for precise cardiac-specific genome editing. RNP complexes containing Cas9 and single guide RNA targeting miR-34a, an MI-associated molecular target, were loaded into EVs (EV@RNP). Gene editing by EV@RNP attenuated hydrogen peroxide-induced apoptosis in cardiomyocytes via miR-34a inhibition, evidenced by increased B-cell lymphoma 2 levels, decreased Bcl-2-associated X protein levels, and the cleavage of caspase-3. Additionally, to improve cardiac targeting in vivo, we used click chemistry to form functional T-EV@RNP by conjugating T peptides to EV@RNP. Consequently, T-EV@RNP-mediated miR-34a genome editing might exert a protective effect against MI, reducing apoptosis, ameliorating MI injury, and facilitating the recovery of cardiac function. In conclusion, the genome editing delivery system established by loading CRISPR/Cas9 RNP with cardiac-targeting EVs is a powerful approach for precise and tissue-specific gene therapy for cardiovascular disease.

Protectin D1 Alleviates Myocardial Ischemia/Reperfusion Injury by Regulating PI3K/AKT Signaling Pathway

Myocardial ischemia/reperfusion (I/R) injury after the onset of acute myocardial infarction (AMI) can be life-threatening, and there is no effective strategy for therapeutic intervention. Here, we studied the potential of protectin D1 in protecting from I/R-induced cardiac damages and investigated the underlying mechanisms. An in vivo rat model of I/R after AMI induction was established through the ligation of the left anterior descending (LAD) artery to assess the cardiac functions and evaluate the protective effect of protectin D1. Protectin D1 protected against I/R-induced oxidative stress and inflammation in the rat model, improved the cardiac function, and reduced the infarct size in myocardial tissues. The beneficial effect of protectin D1 was associated with the up-regulation of miRNA-210 and the effects on PI3K/AKT signaling and HIF-1α expression. Together, our data suggest that protectin D1 could serve as a potential cardioprotective agent against I/R-associated cardiac defects.

Clerodendrum Glandulosum Lindl.: A Review of Ethnopharmacology, Pharmacological Potentials, and their Mechanism of Action

Clerodendrum glandulosum Lindl. is popularly known for its traditional herbal remedies and therapeutic properties among the people of Northeast Indian communities, as well as Chinese traditional medicine. For the myriad pharmacological properties, viz., anti-hypertensive, hypolipidemic, hepatoprotective, anti-inflammatory, and neuroprotective, planting this species in kitchen gardens is a common practice to treat various ailments, especially hypertension, diabetes, and other metabolic complications. Different phytochemicals, representing the diverse classes of secondary metabolites comprising physiological and phytopharmaceutical significance, have been reported from C. glandulosum. Compounds with terpenoids, steroids, and phenolics are in demand in the pharmaceutical industry. An overview of the mechanism of action of the prominent compounds has also been collated for future research on C. glandulosum-based therapeutics. Current information focuses on this important medicinal plant's ethnomedicinal use, phytochemistry, pharmacology, associated mechanisms, and toxicology. This review will help explore this potential medicinal plant, which can pave the path for its application in the pharmaceutical industry.

Myrtenal exhibits cardioprotective effects by attenuating the pathological progression associated with myocardial infarction

BACKGROUND

Myocardial infarction poses major risks to human health because of their incredibly high rates of morbidity and mortality. Infarctions are more likely to develop as a result of dysregulation of cell death. Myrtenal can be considered for their bioactive beneficial activity in the context of cardiovascular pathologies and, particularly, in the protection toward oxidative stress followed by ischemic injury.

OBJECTIVE

This study aimed to put limelight on the antioxidant, anti-apoptotic, and antibacterial properties of Myrtenal.

METHODS

An in vitro model of oxidative stress-induced injury was entrenched in H9c2 cells using hydrogen peroxide, and the effects of Myrtenal were investigated. The MTT, cellular enzyme level, staining, and flow cytometry analysis were used to examine protective, antioxidant, and anti-apoptotic effects. The gene expressions were detected by qPCR. Antibacterial effect and biofilm formation were also done.

RESULT

The findings revealed that Myrtenal alone had negligible cytotoxic effects and that Myrtenal protects H9c2 against H2 O2 -induced cell death at micromolar concentrations. Myrtenal pre-treatment inhibited the generation of reactive oxygen species (ROS) as well as remarkably decreased the fluorescence intensity of ROS. Additionally, Myrtenal considerably increased the synthesis of antioxidant enzymes while dramatically decreasing the production of MDA and LDH. qPCR demonstrated the downregulation of Cas-9, TNF-α, NF-κB, P53, BAX, iNOS, and IL-6 expression while an upregulation of Bcl-2 expression in Myrtenal pre-treated groups. Myrtenal also holds the magnificent property of inhibiting bacterial growth.

CONCLUSION

Myrtenal ameliorates H2 O2 -induced cardiomyocyte injury and protects cardiomyocyte by inhibiting oxidative stress, inflammation, and apoptosis and may be a promise drug for the treatment of heart diseases.

Underlying mechanisms and cardioprotective effects of SGLT2i and GLP-1Ra: insights from cardiovascular magnetic resonance

Originally designed as anti-hyperglycemic drugs, Glucagon-Like Peptide-1 receptor agonists (GLP-1Ra) and Sodium-glucose cotransporter-2 inhibitors (SGLT2i) have demonstrated protective cardiovascular effects, with significant impact on cardiovascular morbidity and mortality. Despite several mechanisms have been proposed, the exact pathophysiology behind these effects is not yet fully understood. Cardiovascular imaging is key for the evaluation of diabetic patients, with an established role from the identification of early subclinical changes to long-term follow up and prognostic assessment. Among the different imaging modalities, CMR may have a key-role being the gold standard for volumes and function assessment and having the unique ability to provide tissue characterization. Novel techniques are also implementing the possibility to evaluate cardiac metabolism through CMR and thereby further increasing the potential role of the modality in this context. Aim of this paper is to provide a comprehensive review of changes in CMR parameters and novel CMR techniques applied in both pre-clinical and clinical studies evaluating the effects of SGLT2i and GLP-1Ra, and their potential role in better understanding the underlying CV mechanisms of these drugs.

Oxidative stress and ion channels in neurodegenerative diseases

Numerous neurodegenerative diseases result from altered ion channel function and mutations. The intracellular redox status can significantly alter the gating characteristics of ion channels. Abundant neurodegenerative diseases associated with oxidative stress have been documented, including Parkinson's, Alzheimer's, spinocerebellar ataxia, amyotrophic lateral sclerosis, and Huntington's disease. Reactive oxygen and nitrogen species compounds trigger posttranslational alterations that target specific sites within the subunits responsible for channel assembly. These alterations include the adjustment of cysteine residues through redox reactions induced by reactive oxygen species (ROS), nitration, and S-nitrosylation assisted by nitric oxide of tyrosine residues through peroxynitrite. Several ion channels have been directly investigated for their functional responses to oxidizing agents and oxidative stress. This review primarily explores the relationship and potential links between oxidative stress and ion channels in neurodegenerative conditions, such as cerebellar ataxias and Parkinson's disease. The potential correlation between oxidative stress and ion channels could hold promise for developing innovative therapies for common neurodegenerative diseases.

Intramyocardial Injection of Hypoxia-Conditioned Extracellular Vesicles Modulates Response to Oxidative Stress in the Chronically Ischemic Myocardium

INTRODUCTION

Patients with advanced coronary artery disease (CAD) who are not eligible for stenting or surgical bypass procedures have limited treatment options. Extracellular vesicles (EVs) have emerged as a potential therapeutic target for the treatment of advanced CAD. These EVs can be conditioned to modify their contents. In our previous research, we demonstrated increased perfusion, decreased inflammation, and reduced apoptosis with intramyocardial injection of hypoxia-conditioned EVs (HEVs). The goal of this study is to further understand the function of HEVs by examining their impact on oxidative stress using our clinically relevant and extensively validated swine model of chronic myocardial ischemia.

METHODS

Fourteen Yorkshire swine underwent a left thoracotomy for the placement of an ameroid constrictor on the left circumflex coronary artery to model chronic myocardial ischemia. After two weeks of recovery, the swine underwent a redo thoracotomy with injection of either HEVs (n = 7) or a saline control (CON, n = 7) into the ischemic myocardium. Five weeks after injection, the swine were subjected to terminal harvest. Protein expression was measured using immunoblotting. OxyBlot analysis and 3-nitrotyrosine staining were used to quantify total oxidative stress.

RESULTS

There was a significant increase in myocardial expression of the antioxidants SOD 2, GPX-1, HSF-1, UCP-2, catalase, and HO-1 (all p ≤ 0.05) in the HEV group when compared to control animals. The HEVs also exhibited a significant increase in pro-oxidant NADPH oxidase (NOX) 1, NOX 3, p47phox, and p67phox (all p ≤ 0.05). However, no change was observed in the expression of NFkB, KEAP 1, and PRDX1 (all p > 0.05) between the HEV and CON groups. There were no significant differences in total oxidative stress as determined by OxyBlot and 3-nitrotyrosine staining (p = 0.64, p = 0.32) between the groups.

CONCLUSIONS

Administration of HEVs in ischemic myocardium induces a significant increase in pro- and antioxidant proteins without a net change in total oxidative stress. These findings suggest that HEV-induced changes in redox signaling pathways may play a role in increased perfusion, decreased inflammation, and reduced apoptosis in ischemic myocardium. Further studies are required to determine if HEVs alter the net oxidative stress in ischemic myocardium at an earlier time point of HEV administration.

Mitochondria-derived methylmalonic acid aggravates ischemia-reperfusion injury by activating reactive oxygen species-dependent ferroptosis

Ferroptosis is a regulatory cell death process pivotal in myocardial ischemia-reperfusion (I/R) injury. However, the precise mechanism underlying myocardial ferroptosis remains less known. In this study, we investigated the pathophysiological mechanisms of methylmalonic acid (MMA) associated with ferroptosis activation in cardiomyocytes after I/R. We found an increase level of MMA in patients with acute myocardial injury after reperfusion and AC16 cells under hypoxia/reoxygenation (H/R) condition. MMA treatment was found to be associated with excessive oxidative stress in cardiomyocytes, leading to ferroptosis-related myocardial injury. In mice with I/R injury, MMA treatment aggravated myocardial oxidative stress and ferroptosis, which amplified the myocardial infarct size and cardiac dysfunction. Mechanistically, MMA promoted NOX2/4 expression to increase reactive oxygen species (ROS) production in cardiomyocytes, aggravating myocardial injury. Notably, the increased ROS further activated ferroptosis by inhibiting solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) expression. In addition, MMA decreased the ectopic nuclear distribution of nuclear factor E2-related factor 2 (NRF2) by increasing the interaction between NRF2 and kelch-like ECH-associated protein 1 (KEAP1). This impeded the activation of GPX4/SLC7A11, downstream of NRF2, activating ferroptosis and aggravating myocardial cell injury. Collectively, our study indicates that MMA activates oxidative stress and ROS generation, which induces ferroptosis to exacerbate cardiomyocyte injury in an I/R model. These findings may provide a new perspective for the clinical treatment of I/R injury and warrant further investigation.

Exploring the molecular mechanism of Yinao Fujian formula on ischemic stroke based on network pharmacology and experimental verification

Background

Ischemic stroke (IS) is a leading cause of long-term disability and even mortality, threatening people's lives. Yinao Fujian (YNFJ) formula is a Traditional Chinese Medicine formula that has been widely used to treat patients with IS. However, the molecular mechanism of YNFJ for the treatment of IS is still elusive. Our study aimed to explore the potential protective effect and the underlying mechanisms of YNFJ on IS using a network pharmacology approach coupled with experimental validation.

Materials and methods

Effective compounds of YNFJ were collected from BATMAN-TCM and TCMSP databases, while IS targets were obtained from GeneCards, OMIM, TTD and DrugBank databases. The protein-protein interaction (PPI) network was constructed to further screen the hub targets of YNFJ in IS treatment. GO and KEGG enrichment analyses were used to identify the critical biological processes and signaling pathways of YNFJ for IS. Moreover, Nissl staining, HE, TTC staining and Tunel staining were used in the MCAO model to prove the neuroprotective effect of YNFJ. Oxidative damage, inflammatory factor release and related pathways were tested in MCAO rat model and hypoxia-induced BV2 cell model, respectively.

Results

We found that YNFJ treatment significantly alleviated MCAO-induced nerve damage and apoptosis. Then, network pharmacology screening combined with literature research revealed IL6, TNF, PTGS2, NFKBIA and NFE2L2 as the critical targets in a PPI network. Moreover, the top 20 signaling pathways and biological processes associated with the protective effects of YNFJ on IS were enriched through GO and KEGG analyses. Further analysis indicated that NF-κB and Nrf2/HO-1 signaling pathways might be highly involved in the protective effects of YNFJ on IS. Finally, in vitro and in vivo experiments confirmed that YNFJ inhibited the release of inflammatory factors (IL-6 and TNF-α) and MDA content, and increased the activity of SOD. In terms of the mechanism, YNFJ inhibited the release of inflammatory factors by suppressing the NF-κB pathway and decreased the expression of iNOS and COX-2 to protect microglia from inflammation damage. In addition, YNFJ initiated the dissociation of Keap-1 and Nrf2, and activated the downstream protein HO-1, NQO1, thus decreasing oxidative stress.

Conclusion

Taken together, the findings in our research showed that the protective effects of YNFJ on IS were mainly achieved by regulating the NF-κB and Nrf2/HO-1 signaling pathways to inhibit oxidative stress damage and inflammatory damage of microglia.

Cardioprotective effects of asiaticoside against diabetic cardiomyopathy: Activation of the AMPK/Nrf2 pathway

Diabetic cardiomyopathy (DCM) is a chronic microvascular complication of diabetes that is generally defined as ventricular dysfunction occurring in patients with diabetes and unrelated to known causes. Several mechanisms have been proposed to contribute to the occurrence and persistence of DCM, in which oxidative stress and autophagy play a non-negligible role. Diabetic cardiomyopathy is involved in a variety of physiological and pathological processes. The 5' adenosine monophosphate-activated protein kinase/nuclear factor-erythroid 2-related factor 2 (AMPK/Nrf2) are expressed in the heart, and studies have shown that asiaticoside (ASI) and activated AMPK/Nrf2 have a protective effect on the myocardium. However, the roles of ASI and AMPK/Nrf2 in DCM are unknown. The intraperitoneal injection of streptozotocin (STZ) and high-fat feed were used to establish the DCM models in 100 C57/BL mice. Asiaticoside and inhibitors of AMPK/Nrf2 were used for intervention. Cardiac function, oxidative stress, and autophagy were measured in mice. DCM mice displayed increased levels of oxidative stress while autophagy levels declined. In addition, AMPK/Nrf2 was activated in DCM mice with ASI intervention. Further, we discovered that AMPK/Nrf2 inhibition blocked the protective effect of ASI by compound C and treatment with ML-385. The present study demonstrates that ASI exerts a protective effect against DCM via the potential activation of the AMPK/Nrf2 pathway. Asiaticoside is a potential therapeutic target for DCM.

Circadian regulated control of myocardial ischemia-reperfusion injury

Circadian mechanisms have been associated with the pathogenesis of a variety of cardiovascular diseases, including myocardial ischemia-reperfusion injury (I-R). Myocardial ischemia resulting from impaired oxygen delivery to cardiac muscle sets into motion a cascade of cellular events that paradoxically triggers greater cardiac dysfunction upon reinstitution of coronary blood supply, a phenomenon known as I-R. I-R injury has been attributed to a number of cellular defects including increased reactive oxygen species (ROS), increased intracellular calcium and impaired mitochondrial bioenergetics that ultimately lead to cardiac cell death, ventricular remodeling and heart failure. Emerging evidence has identified a strong correlation between cellular defects that underlie I-R and the disrupted circadian. In fact, recent studies have shown that circadian dysfunction exacerbates cardiac injury following MI from impaired cellular quality control mechanisms such as autophagy, which are vital in the clearance of damaged cellular proteins and organelles such as mitochondria from the cell. The accumulation of cellular debris is posited as the central underlying cause of excessive cardiac cell death and ventricular dysfunction following MI. The complexities that govern the interplay between circadian biology and I-R injury following MI is at its infancy and understanding how circadian misalignment, such as in shift workers impacts I-R injury is of great scientific and clinical importance toward development of new therapeutic strategies using chronotherapy and circadian regulation to mitigate cardiac injury and improve cardiac outcomes after injury. In this review, we highlight recent advances in circadian biology and adaptive cellular quality control mechanisms that influence cardiac injury in response to MI injury with a specific focus on how circadian biology can be utilized to further cardiovascular medicine and patient care.

Aldehyde Dehydrogenase 2 Preserves Mitochondrial Function in the Ischemic Heart: A Redox-dependent Mechanism for AMPK Activation by Thioredoxin-1

ABSTRACT

Aldehyde dehydrogenase 2 (ALDH2) protects the ischemic heart by activating adenosine 5'-monophosphate-activated protein kinase (AMPK) signaling. However, the molecular mechanisms linking ALDH2 and AMPK signaling are not fully understood. This study aimed to explore the potential mechanisms linking ALDH2 and AMPK in myocardial ischemic injury. An ischemic model was established by ligating the left anterior descending coronary artery in rats. The overexpression or knockdown of ALDH2 in H9c2 cells treated with oxygen-glucose deprivation was obtained through lentivirus infection. Transferase-mediated dUTP nick-end labeling was used to evaluate apoptosis in an ischemic rat model and oxygen-glucose deprivation cells. ALDH2 activity, mitochondrial oxidative stress markers, adenosine triphosphate, respiratory control ratio, and cell viability in H9c2 cells were evaluated using a biological kit and 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide. Protein expression of ALDH2 , 4-hydroxynonenal, thioredoxin-1 (Trx-1), and AMPK-proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) signaling pathway was detected through Western blotting. ALDH2 activation reduced ischemic-induced myocardial infarct size and apoptosis. ALDH2 protected mitochondrial function by enhancing mitochondrial respiratory control ratio and adenosine triphosphate production, alleviated mitochondrial oxidative stress, and suppressed myocardial apoptosis. Moreover, ALDH2 attenuated ischemia-induced oxidative stress and maintained Trx-1 levels by reducing 4-hydroxynonenal, thereby promoting AMPK-PGC-1α signaling activation. Inhibiting Trx-1 or AMPK abolished the cardioprotective effect of ALDH2 on ischemia. ALDH2 alleviates myocardial injury through increased mitochondrial biogenesis and reduced oxidative stress, and these effects were achieved through Trx1-mediating AMPK-PGC1-α signaling activation.

Effects of coenzyme Q10 supplementation on oxidative stress biomarkers following reperfusion in STEMI patients undergoing primary percutaneous coronary intervention

Introduction

It is well-established that oxidative stress is deeply involved in myocardial ischemia-reperfusion injury. Considering the potent antioxidant properties of coenzyme Q10 (CoQ10), we aimed to assess whether CoQ10 supplementation could exert beneficial effects on plasma levels of oxidative stress biomarkers in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPIC).

Methods

Seventy patients with the first attack of STEMI, eligible for PPCI were randomly assigned to receive either standard treatments plus CoQ10 (400 mg before PPCI and 200 mg twice daily for three days after PPCI) or standard treatments plus placebo. Plasma levels of oxidative stress biomarkers, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), total antioxidant capacity (TAC), and malondialdehyde (MDA) were measured at 6, 24, and 72 hours after completion of PPCI.

Results

The changes in plasma levels of the studied biomarkers at 6 and 24 hours after PPCI were similar in the both groups (P values>0.05). This is while at 72 hours, the CoQ10- treated group exhibited significantly higher plasma levels of SOD (P value<0.001), CAT (P value=0.001), and TAC (P value<0.001), along with a lower plasma level of MDA (P value=0.002) compared to the placebo-treated group. The plasma activity of GPX showed no significant difference between the groups at all the study time points (P values>0.05).

Conclusion

This study showed that CoQ10 has the potential to modulate the balance between antioxidant and oxidant biomarkers after reperfusion therapy. Our results suggest that CoQ10, through its antioxidant capacity, may help reduce the reperfusion injury in ischemic myocardium.

Mitochondrial transplantation reduces lower limb ischemia-reperfusion injury by increasing skeletal muscle energy and adipocyte browning

Recent studies have shown that mitochondrial transplantation can repair lower limb IRI, but the underlying mechanism of the repair effect remains unclear. In this study, we found that in addition to being taken up by skeletal muscle cells, human umbilical cord mesenchymal stem cells (hMSCs)-derived mitochondria were also taken up by adipocytes, which was accompanied by an increase in optic atrophy 1 (OPA1) and uncoupling protein 1. Transplantation of hMSCs-derived mitochondria could not only supplement the original damaged mitochondrial function of skeletal muscle, but also promote adipocyte browning by increasing the expression of OPA1. In this process, mitochondrial transplantation can reduce cell apoptosis and repair muscle tissue, which promotes the recovery of motor function in vivo. To the best of our knowledge, there is no study on the therapeutic mechanism of mitochondrial transplantation from this perspective, which could provide a theoretical basis.

Comparison of the preconditioning effect of different exercise training modalities on myocardial ischemia-reperfusion injury

The study of exercise preconditioning can develop strategies to prevent cardiovascular diseases and outline the efficient exercise model. However, the exercise type with the most protective effect against ischemia-reperfusion injury is unknown. In this study, we examined the effects of three kinds of exercise preconditioning on myocardial ischemia-reperfusion in adult rats and explored the possible underlying mechanisms. Male Wistar rats subjected to ten weeks of endurance, resistance, and concurrent training underwent ischemia (30 min) and reperfusion (120 min) induction. Then, infarction size, serum levels of the CK-MB, the redox status, and angiogenesis proteins (VEGF, ANGP-1, and ANGP-2) were measured in the cardiac tissue. Results showed that different exercise training modes have the same reduction effects on infarction size, but ischemia-reperfusion-induced CK-MB was lower in response to endurance training and concurrent training. Furthermore, cardiac VEGF levels increased in all three kinds of exercise preconditioning but ischemia-reperfusion-induced ANGP-1 elevated more in endurance training. The cardiac GPX activity was improved significantly through the resistance and concurrent exercise compared to the endurance exercise. In addition, all three exercise preconditioning models decreased MPO levels, and ischemia reperfusion-induced MDA was lower in endurance and resistance training. Overall, these results indicated that cardioprotection of exercise training against ischemia-reperfusion injury depends on the exercise modality. Cardioprotective effects of aerobic, resistance, and concurrent exercises are due to different mechanisms. The preconditioning effects of endurance training are mediated mainly by pervasive angiogenic responses and resistance training through oxidative stress amelioration. The preconditioning effects of concurrent training rely on both angiogenesis and oxidative stress amelioration.

Design and synthesis of 3,4-seco-lupane triterpene derivatives to resist myocardial ischemia-reperfusion injury by inhibiting oxidative stress-mediated mitochondrial dysfunction via the PI3K/AKT/HIF-1α axis

In this study, 86 new seco-lupane triterpenoid derivatives were designed, synthesized, and characterized, and their protective activities against ischemia-reperfusion injury were investigated in vitro and in vivo. Structure-activity relationship studies revealed that most target compounds could protect cardiomyocytes against hypoxia/reoxygenation-induced injury in vitro, with compound 85 being the most active and exhibiting more potent protective activity than clinical first-line drugs. Furthermore, all thiophene derivatives exhibited stronger protective activity than furan, pyridine, and pyrazine derivatives, and the protective activity gradually increased with the extension of the alkyl chain and changed in the substituent. The data from the in-vitro and in-vivo experiments revealed that compound 85 protected mitochondria from damage by inhibiting excessive production of oxidative stressors, such as intracellular ROS, which in turn inhibited the apoptosis and necrotize of cardiomyocytes and reduced infarct size, thereby protecting normal cardiac function. It was associated with enhanced activation of the PI3K/AKT-mediated HIF-1α signaling pathway. Therefore, compound 85 acts as an oxidative stress inhibitor, blocks ROS production, protects mitochondria and cells from myocardial ischemia/reperfusion (MI/R) injury, and represents an effective new drug for treating MI/R injury.

Dexmedetomidine attenuates myocardial ischemia-reperfusion injury in hyperlipidemic rats by inhibiting inflammation, oxidative stress and NF-κB

The present study was conducted to determine the protective effect of Dexmedetomidine (DEX) in myocardial ischemia-reperfusion injury in hyperlipidemic rats. Towards this, the effect of DEX was first evaluated on the infarct size and the histopathology of cardiac tissues using TTC and H and E staining, and it was found that DEX significantly improved the infarct size and architecture of the myocardial tissues following the I/R injury. DEX also showed significant improvement in various examined hemodynamic parameters (e.g., LVSP, and ± dp/dtmax ) in a dose-dependent manner. The lipid profile (LDL, VLDL, TC, TG, and HDL level) of the rats were also found significantly improved in DEX-treated rats. The level of various pro-inflammatory cytokines (IL-1β, IL-6, IL-10, IL-17, and TNF-α), cardiac injury (CK, CK-MB, Troponin I AST, ALT, and LDH), and oxidative stress (MDA, SOD, and GSH) biomarkers were also found to be restored near to the normal in DEX-treated group. It has been found that DEX also significantly reduces apoptosis of rat cardiomyocytes. In western blot analysis, DEX showed a significant reduction in the activation of NF-κB. In conclusion, our study demonstrated the protective effect of Dexmedetomidine in myocardial ischemia-reperfusion injury in hyperlipidemic rats possibly via amelioration of oxidative stress, and inflammation apoptosis.

Mannose binding lectin-associated serine protease-1 is a novel contributor to myocardial ischemia/reperfusion injury

BACKGROUND

The lectin pathway has been demonstrated to play a critical role in the pathological process of myocardial ischemia/reperfusion injury (IRI). Mannose-binding lectin (MBL)-associated serine protease-1 (MASP-1), especially different from other components of the lectin pathway, mediates proinflammatory and procoagulant reactions independent of complement cascades. However, the role of MASP-1 in myocardial IRI remains unknown so far.

METHODS

Myocardial IRI was established with 45 min ischemia and 24 h reperfusion in mice. C1 inhibitor, as the natural inhibitor of MASP-1, was administrated at 20 IU/Kg via tail vein 5 min before surgical operation. Cardiac function and myocardial infarct size were assessed. Myocardial histology and fibrosis were evaluated by H&E and Masson staining, respectively. Deposition of MASP-1, expression of PAR-1/4 and neutrophil extracellular traps (NET) were investigated on myocardium tissue by IHC staining. Cell apoptosis was detected by TUNEL assay. Levels of myocardial enzymes and proinflammatory cytokines were determined by ELISA.

RESULTS

Inhibition of MASP-1 with C1 INH improved cardiac function and alleviated myocardium tissue injury (infarct size, enzymes, histology and fibrosis) after myocardial IRI. Deposition of MASP-1 and expression PAR-1, as well as NET formation in myocardial tissue were suppressed by MASP-1 inhibitor, while PAR-4 was elevated. Levels of apoptosis, HMGB-1 and IL-6 were lower after blocking MASP-1. Yet, IL-8 and TNF-α remained unchanged.

CONCLUSIONS

MASP-1, as a new contributor, played a critical role in myocardial IRI. Inhibition of MASP-1 protected myocardial tissue from IRI probably via regulation of PARs/NET pathway. This may provide a novel target strategy against myocardial IRI.

Effects of electrospun fibers containing ascorbic acid on oxidative stress reduction for cardiac tissue engineering

Tissue engineering provides promise for regeneration of cardiac tissue following myocardial infarction. However, the harsh microenvironment of the infarct hampers the efficacy of regenerative therapies. Ischemia-reperfusion injury dramatically increases the levels of reactive oxygen species (ROS) within the infarcted area, causing a cascade of further cellular injury. Implantable tissue engineered grafts can target this oxidative stress by delivering pharmaceutical compounds directly into the diseased tissue. Herein, we successfully fabricated electrospun polycaprolactone (PCL) fibers containing varying concentrations of ascorbic acid, a potent antioxidant well known for its ROS-scavenging capabilities. The antioxidant scaffolds displayed significantly improved scavenging of DPPH radicals, superoxide anions and hydroxyl radicals, in a dose dependent manner. Mechanical properties testing indicated that incorporation of ascorbic acid enhanced the strength and Young's modulus of the material, correlating with a moderate but non-significant increase in the crystallinity. Moreover, the scaffolds supported adhesion and maintained survival of human umbilical vein endothelial cells in vitro, indicating good cytocompatibility. These results provide motivation for the use of ascorbic acid-containing fibrous scaffolds to regulate the highly oxidative microenvironment following myocardial infarction.

Association of prognostic nutritional index with long-term mortality in patients receiving percutaneous coronary intervention for acute coronary syndrome: a meta-analysis

The predictive value of the prognostic nutritional index (PNI) for the long-term prognosis of patients with acute coronary syndrome (ACS) remains uncertain. Medline, Embase, Cochrane Library, and Google Scholar were searched from inception until January 2023 to study the relationship between all-cause mortality risk and PNI in patients receiving percutaneous coronary intervention for ACS (i.e., primary outcome). Thirteen observational studies were included in this meta-analysis. Analysis of seven studies using PNI as a categorical variable showed a pooled hazard ratio (HR) of all-cause mortality of 2.97 (95% CI 1.65 to 5.34, p = 0.0003, I2 = 89%, n = 11,245) for patients with a low PNI. The meta-analysis also showed a higher risk of major adverse cardiovascular events (MACEs) in patients with a low PNI (HR 2.04; 95% CI 1.59 to 2.61; p < 0.00001; I2 = 21%; n = 8534). Moreover, advanced age, diabetes mellitus, and high Global Registry of Acute Coronary Events risk scores were associated with a high risk of all-cause mortality, whereas a high body mass index was associated with a low risk of all-cause mortality. The results showed an association between a low PNI and an increased risk of long-term mortality in patients undergoing coronary interventions for ACS. Further randomized controlled trials are necessary to confirm these findings.

Potential of graphene-based nanomaterials for cardiac tissue engineering

Cardiovascular diseases are the primary cause of death worldwide. Despite significant advances in pharmacological treatments and surgical interventions to restore heart function after myocardial infarction, it can progress to heart failure due to the restricted inherent potential of adult cardiomyocytes to self-regenerate. Hence, the evolution of new therapeutic methods is critical. Nowadays, novel approaches in tissue engineering have assisted in restoring biological and physical specifications of the injured myocardium and, hence, cardiac function. The incorporation of a supporting matrix that could mechanically and electronically support the heart tissue and stimulate the cells to proliferate and regenerate will be advantageous. Electroconductive nanomaterials can facilitate intracellular communication and aid synchronous contraction via electroactive substrate creation, preventing the issue of arrhythmia in the heart. Among a wide range of electroconductive materials, graphene-based nanomaterials (GBNs) are promising for cardiac tissue engineering (CTE) due to their outstanding features including high mechanical strength, angiogenesis, antibacterial and antioxidant properties, low cost, and scalable fabrication. In the present review, we discuss the effect of applying GBNs on angiogenesis, proliferation, and differentiation of implanted stem cells, their antibacterial and antioxidant properties, and their role in improving the electrical and mechanical properties of the scaffolds for CTE. Also, we summarize the recent research that has applied GBNs in CTE. Finally, we present a concise discussion on the challenges and prospects.

Regulatory effects of trimetazidine in cardiac ischemia/reperfusion injury

Ischemia/reperfusion (I/R) injury is a tissue damage during reperfusion after an ischemic condition. I/R injury is induced by pathological cases including stroke, myocardial infarction, circulatory arrest, sickle cell disease, acute kidney injury, trauma, and sleep apnea. It can lead to increased morbidity and mortality in the context of these processes. Mitochondrial dysfunction is one of the hallmarks of I/R insult, which is induced via reactive oxygen species (ROS) production, apoptosis, and autophagy. MicroRNAs (miRNAs, miRs) are non-coding RNAs that play a main regulatory role in gene expression. Recently, there are evidence, which miRNAs are the major modulators of cardiovascular diseases, especially myocardial I/R injury. Cardiovascular miRNAs, specifically miR-21, and probably miR-24 and miR-126 have protective effects on myocardial I/R injury. Trimetazidine (TMZ) is a new class of metabolic agents with an anti-ischemic activity. It has beneficial effects on chronic stable angina by suppressing mitochondrial permeability transition pore (mPTP) opening. The present review study addressed the different mechanistic effects of TMZ on cardiac I/R injury. Online databases including Scopus, PubMed, Web of Science, and Cochrane library were assessed for published studies between 1986 and 2021. TMZ, an antioxidant and metabolic agent, prevents the cardiac reperfusion injury by regulating AMP-activated protein kinase (AMPK), cystathionine-γ-lyase enzyme (CSE)/hydrogen sulfide (H2S), and miR-21. Therefore, TMZ protects the heart against I/R injury by inducing key regulators such as AMPK, CSE/H2S, and miR-21.

The Role of Systemic Oxidative Status in Coronary Arterial and Peripheral Venous Blood of Patients with Unstable Angina Pectoris

(1) Background: We aimed to analyze the oxidative status of patients with unstable angina pectoris (UA), as well as to determine the correlation of these parameters between coronary arterial and peripheral venous blood samples. (2) Methods: The study included 47 human subjects with UA and 45 control subjects. We performed clinical examinations, hemodynamic and coronary angiography measures. Also, in the blood samples, we measured routine laboratory markers and the concentration of pro-oxidants: index of lipid peroxidation (TBARS), superoxide anion radical (O₂^-), hydrogen peroxide (H₂O₂) and nitrites (NO₂^-), while antioxidant parameters were determined from red blood cells: reduced glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD). All parameters were determined spectrophotometrically. (3) Results: Significantly higher values of TBARS and all measured antioxidants SOD, CAT and GSH were observed in the coronary arterial blood of the UA group relative to coronary arterial blood of the control subjects. On the other hand, in the peripheral venous blood samples, a significantly lower GSH value was found in the UA group compared to the control. (4) Conclusions: This study has shown that the majority of changes in all measured redox markers are found in coronary blood, especially related to the activity of antioxidant components. In patients with an unstable form of angina, prooxidants (superoxide anion radical and index of lipid peroxidation) and endogenous antioxidants (catalase, superoxide dismutase and reduced glutathione) are in direct correlation with the course of ischemic disease. Future studies, where participants would be randomized depending on symptom duration, are necessary to confirm these conclusions.

Stem cell therapy for acute myocardial infarction: Mesenchymal Stem Cells and induced Pluripotent Stem Cells

INTRODUCTION

Acute myocardial infarction (AMI) remains a leading cause of death in the United States. The limited capacity of cardiomyocytes to regenerate and the restricted contractility of scar tissue after AMI are not addressed by current pharmacologic interventions. Mesenchymal stem/stromal cells (MSCs) have emerged as a promising therapeutic approach due to their low antigenicity, ease of harvesting, and efficacy and safety in preclinical and clinical studies, despite their low survival and engraftment rates. Other stem cell types, such as induced pluripotent stem cells (iPSCs) also show promise, and optimizing cardiac repair requires integrating emerging technologies and strategies.

AREAS COVERED

This review offers insights into advancing cell-based therapies for AMI, emphasizing meticulously planned trials with a standardized definition of AMI, for a bench-to-bedside approach. We critically evaluate fundamental studies and clinical trials to provide a comprehensive overview of the advances, limitations and prospects for cell-based therapy in AMI.

EXPERT OPINION

MSCs continue to show potential promise for treating AMI and its sequelae, but addressing their low survival and engraftment rates is crucial for clinical success. Integrating emerging technologies such as pluripotent stem cells and conducting well-designed trials will harness the full potential of cell-based therapy in AMI management. Collaborative efforts are vital to developing effective stem cell therapies for AMI patients.

Prognostic Value of Redox Status Biomarkers in Patients Presenting with STEMI or Non-STEMI: A Prospective Case-Control Clinical Study

(1) Background: The aim of our study was to determine the role of oxidative stress (OS) during early evaluation of acute ST-elevated myocardial infarction (STEMI) and non-ST-elevated myocardial infarction (NSTEMI) patients in order to define the role of redox balance in profiling the development of myocardial infarction (MI). (2) Methods: This prospective observational case-control study included 40 consecutive STEMI and 39 NSTEMI patients hospitalized in the coronary care unit of the cardiology clinic at the Kragujevac Clinical Center, Serbia, between 1 January 2016 and 1 January 2017. Blood samples were collected from all patients for measuring cardio-specific enzymes at admission and 12 h after admission to evaluate systemic oxidative stress biomarkers and the activity of antioxidant enzymes. (3) Results: In this study, participants were predominately female (52%), with a mean age of 56.17 ± 1.22 years old in the STEMI group and 69.17 ± 3.65 in the non-STEMI group. According to the Killip classification, the majority of patients (>50%) were at the second and third level. We confirmed the elevation of superoxide anion radicals in the non-STEMI group 6 h after admission in comparison with the STEMI and CTRL groups, but levels had decreased 12 h after admission. Levels of hydrogen peroxide were statistically significantly increased in the NSTEMI group. A positive correlation of superoxide anion radicals and levels of troponin I at admission was observed (r = 0.955; p = 0.045), as well as an inverse correlation between reduced glutathione and levels of NT-pBNP measured 6 h after admission (r = -0.973; p = 0.027). (4) Conclusions: We confirmed that superoxide anion radicals and reduced glutathione observed together with hs-troponin I at admission and NT-pBNP during hospital treatment could be predictors of ST evolution.

Predicting thrombotic cardiovascular outcomes induced by waterpipe-associated chemicals using comparative toxicogenomic database: Genes, phenotypes, and pathways

Hookah, or waterpipe, is a tobacco smoking device that has gained popularity in the United States. A growing body of evidence demonstrates that waterpipe smoke (WPS) is associated with various adverse effects on human health, including infectious diseases, cancer, and cardiovascular diseases (CVDs), particularly thrombotic events. However, the molecular mechanisms through which WPS contributes to disease development remain unclear. In this study, we utilized an analytical approach based on the Comparative Toxicogenomics Database (CTD) to integrate chemical, gene, phenotype, and disease data to predict potential molecular mechanisms underlying the effects of WPS, based on its chemical and toxicant profile. Our analysis revealed that CVDs were among the top disease categories with regard to the number of curated interactions with WPS chemicals. We identified 5674 genes common between those modulated by WPS chemicals and traditional tobacco smoking. The CVDs with the most curated interactions with WPS chemicals were hypertension, atherosclerosis, and myocardial infarction, whereas "particulate matter", "heavy metals", and "nicotine" showed the highest number of curated interactions with CVDs. Our analysis predicted that the potential mechanisms underlying WPS-induced thrombotic diseases involve common phenotypes, such as inflammation, apoptosis, and cell proliferation, which are shared across all thrombotic diseases and the three aforementioned chemicals. In terms of enriched signaling pathways, we identified several, including chemokine and MAPK signaling, with particulate matter exhibiting the most statistically significant association with all 12 significant signaling pathways related to WPS chemicals. Collectively, our predictive comprehensive analysis provides evidence that WPS negatively impacts health and offers insights into the potential mechanisms through which it exerts these effects. This information should guide further research to explore and better understand the WPS and other tobacco product-related health consequences.

Molecular targets for anti-oxidative protection of açaí berry against diabetes myocardial ischemia/reperfusion injury

Myocardial ischemia/reperfusion injury (MIRI) is the principal cause of death and occurs after prolonged blockage of the coronary arteries. Diabetes represents one of the main factors aggravating myocardial injury. Restoring blood flow is the first intervention against a heart attack, although reperfusion process could cause additional damage, such as the overproduction of reacting oxygen species (ROS). In recent years, açaí berry has gained international attention as a functional food due to its antioxidant and anti-inflammatory properties; not only that but this fruit has shown glucose-lowering effects. Therefore, this study was designed to evaluate the cardioprotective effects of açaí berry on the inflammatory and oxidative responses associated with diabetic MIRI. Diabetes was induced in rats by a single intravenous inoculation of streptozotocin (60 mg/kg) and allowed to develop for 60 days. MIRI was induced by occlusion of the left anterior descending coronary artery for 30 min followed by 2 h of reperfusion. Açaí (200 mg/kg) was administered 5 min before the end of ischemia and 1 h after reperfusion. In this study, we clearly demonstrated that açaí treatment was able to reduce biomarkers of myocardial damage, infarct size, and apoptotic process. Moreover, açaí administrations reduced inflammatory and oxidative response, modulating Nf-kB and Nrf2 pathways. These results suggest that açai berry supplementation could represent a useful strategy for pathological events associated to MIRI.

Mn(III) Porphyrin, MnTnBuOE-2-PyP5+, Commonly Known as a Mimic of Superoxide Dismutase Enzyme, Protects Cardiomyocytes from Hypoxia/Reoxygenation Induced Injury via Reducing Oxidative Stress

Myocardial ischemia-reperfusion injury (I/R) causes damage to cardiomyocytes through oxidative stress and apoptosis. We investigated the cardioprotective effects of MnTnBuOE-2-PyP5+ (BMX-001), a superoxide dismutase mimic, in an in vitro model of I/R injury in H9c2 cardiomyocytes. We found that BMX-001 protected against hypoxia/reoxygenation (H/R)-induced oxidative stress, as evident by a significant reduction in intracellular and mitochondrial superoxide levels. BMX-001 pre-treatment also reduced H/R-induced cardiomyocyte apoptosis, as marked by a reduction in TUNEL-positive cells. We further demonstrated that BMX-001 pre-treatment significantly improved mitochondrial function, particularly O2 consumption, in mouse adult cardiomyocytes subjected to H/R. BMX-001 treatment also attenuated cardiolipin peroxidation, 4-hydroxynonenal (4-HNE) level, and 4-HNE adducted proteins following H/R injury. Finally, the pre-treatment with BMX-001 improved cell viability and lactate dehydrogenase (LDH) activity in H9c2 cells following H/R injury. Our findings suggest that BMX-001 has therapeutic potential as a cardioprotective agent against oxidative stress-induced H/R damage in H9c2 cardiomyocytes.

α1A Adrenoreceptor blockade attenuates myocardial infarction by modulating the integrin-linked kinase/TGF-β/Smad signaling pathways

Background

Myocardial infarction (MI) is considered a public health problem. According to the World Health Organization, MI is a leading cause of death and comorbidities worldwide. Activation of the α1A adrenergic receptor is a contributing factor to the development of MI. Tamsulosin, an α1A adrenergic blocker, has gained wide popularity as a medication for the treatment of benign prostatic hyperplasia. Limited evidence from previous studies has revealed the potential cardioprotective effects of tamsulosin, as its inhibitory effect on the α1A adrenoceptor protects the heart by acting on the smooth muscle of blood vessels, which results in hypotension; however, its effect on the infarcted heart is still unclear. The mechanisms of the expected cardioprotective effects mediated by tamsulosin are not yet understood. Transforming growth factor-beta (TGF-β), a mediator of fibrosis, is considered an attractive therapeutic target for remodeling after MI. The role of α1A adrenoceptor inhibition or its relationships with integrin-linked kinase (ILK) and TGF-β/small mothers against decapentaplegic (Smad) signaling pathways in attenuating MI are unclear. The present study was designed to investigate whether tamsulosin attenuates MI by modulating an ILK-related TGF-β/Smad pathway.

Methods

Twenty-four adult male Wistar rats were randomly divided into 4 groups: control, ISO, TAM, and ISO + TAM. ISO (150 mg/kg, intraperitoneally) was injected on Days 20 and 21 to induce MI. Tamsulosin (0.8 mg/kg, orally) was administered for 21 days, prior to ISO injection for 2 consecutive days. Heart-to-body weight ratios and cardiac and fibrotic biomarker levels were subsequently determined. ILK, TGF-β1, p-Smad2/3, and collagen III protein expression levels were determined using biomolecular methods.

Results

Tamsulosin significantly attenuated the relative heart-to-body weight index (p < 0.5) and creatine kinase-MB level (p < 0.01) compared with those in the ISO control group. While ISO resulted in superoxide anion production and enhanced oxidative damage, tamsulosin significantly prevented this damage through antioxidant defense mechanisms, increasing glutathione and superoxide dismutase levels (p < 0.05) and decreasing lipid peroxide oxidation levels (p < 0.01). The present data revealed that tamsulosin reduced TGF-β/p-Smad2/3 expression and enhanced ILK expression.

Conclusion

Tamsulosin may exert a cardioprotective effect by modulating the ILK-related TGF-β/Smad signaling pathway. Thus, tamsulosin may be a useful therapeutic approach for preventing MI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-023-03188-w.

The protective effect of rivaroxaban with or without aspirin on inflammation, oxidative stress, and platelet reactivity in isoproterenol-induced cardiac injury in rats

Coronary artery diseases are principal sources of mortality and disability in global human population. Progressively, rivaroxaban is being evaluated for the prevention of atherosclerotic thrombi, particularly with anti-platelet agents. Hence, the current report aimed to investigate the cardioprotective effect of rivaroxaban on isoproterenol (ISO)-induced cardiac injury model in rats and the possible synergistic effect when combined with aspirin. Male Wistar rats were randomly assigned into five different groups. Cardiac injury was induced by subcutaneous injection of ISO (85 mg/kg) for 2 consecutive days. Rat tail bleeding time was performed prior to sacrifice. Cardiac enzymes, platelet activity, inflammatory, and oxidative stress biomarkers levels were measured using enzyme-linked immunoassay (ELISA). Pre-administration of rivaroxaban alone and on combination with aspirin prevented ISO-induced increase in cardiac thiobarbituric acid reactive substances (TBARS), interleukin 6 (IL-6), and thromboxane B2 (TXB2) levels. Moreover, a significant prolongation of bleeding time was demonstrated among aspirin, rivaroxaban, and aspirin plus rivaroxaban treated groups. On the other hand, the combination treatment of aspirin plus rivaroxaban showed no marked difference in these biomarkers and bleeding time relative to either drug administered separately. However, a prominent decrease of cardiac 6-keto prostaglandin F1α (6-Keto-PGF1α) level was displayed in the combination treatment when compared with ISO and rivaroxaban-treated groups, whereas no significant improvement was seen in cardiac glycoprotein V (GPV) levels except in aspirin-treated group. The study results demonstrated that rivaroxaban decreases cardiac oxidative stress, inflammation, and platelets reactivity. However, the addition of rivaroxaban to aspirin did not seem to show synergistic antioxidant, anti-inflammatory, or antiplatelet effect.

Ketogenic Diet and Ketone Bodies against Ischemic Injury: Targets, Mechanisms, and Therapeutic Potential

The ketogenic diet (KD) has been used as a treatment for epilepsy since the 1920s, and its role in the prevention of many other diseases is now being considered. In recent years, there has been an intensive investigation on using the KD as a therapeutic approach to treat acute pathologies, including ischemic ones. However, contradictory data are observed for the effects of the KD on various organs after ischemic injury. In this review, we provide the first systematic analysis of studies conducted from 1980 to 2022 investigating the effects and main mechanisms of the KD and its mimetics on ischemia-reperfusion injury of the brain, heart, kidneys, liver, gut, and eyes. Our analysis demonstrated a high diversity of both the composition of the used KD and the protocols for the treatment of animals, which could be the reason for contradictory effects in different studies. It can be concluded that a true KD or its mimetics, such as β-hydroxybutyrate, can be considered as positive exposure, protecting the organ from ischemia and its negative consequences, whereas the shift to a rather similar high-calorie or high-fat diet leads to the opposite effect.

Klotho improves cardiac fibrosis, inflammatory cytokines, ferroptosis, and oxidative stress in mice with myocardial infarction

The anti-aging protein Klotho has been associated with cardiovascular health protection. Nevertheless, the protective mechanism remains unknown. The present study is aimed at exploring the effect of Klotho on cardiac remodeling and its potential mechanism in mice with myocardial infarction (MI). We used left anterior coronary artery descending ligation to develop an MI model for in vivo analyses. In contrast, H9C2 cells and cardiac fibroblasts were used to establish the oxygen-glucose deprivation (OGD) model in in vitro analyses. In vivo and in vitro models were treated with Klotho. Compound C, an AMPK signaling inhibitor, was used to determine whether Klotho's effects are mediated through the AMPK/mTOR signaling pathway. Echocardiography, Masson trichrome staining, immunofluorescence, immunohistochemistry, real-time polymerase chain reaction (RT-PCR), and western blot were used to detect the related indicators. The findings of the in vivo model indicate that Klotho treatment improved the mice's cardiac function, reduced cardiac fibrosis, and attenuated myocardial inflammatory factors, ferroptosis, and oxidative stress. The results of the in vitro model were in line with the findings of in vivo modeling. An AMPK inhibitor, Compound C, reversed all these effects. In conclusion, Klotho potentially improves cardiac remodeling in MI mice by regulating AMPK/mTOR signaling, demonstrating Klotho as an effective MI therapeutic agent.

Ameliorative Effects of Ponicidin Against the Isoproterenol-induced Acute Myocardial Infarction in Rats

Background

Cardiovascular disease (CVD) is a group of heart disorders, which is a major cause of noncommunicable disease-related mortalities worldwide. Myocardial infarction (MI) is an acute disorder due to the poor supply of oxygen and blood to the myocardium. MI is the foremost form of CVD, which is the primary cause of mortality worldwide.

Objectives

Here, we intended to discover the ameliorative properties of the ponicidin against the isoproterenol (ISO)-stimulated MI in rats.

Methodology

About 85 mg/kg of ISO was administered to the rats to trigger the MI and then treated with 25 and 50 mg/kg of ponicidin. The body weight and heart weight of all rats were determined. The total protein, c-reactive protein (CRP), and uric acid levels were examined. The activities of cardiac function markers such as creatine kinase (CK), ALT, AST, and gamma-glutamyl transferase (GGT) were examined. The antioxidants such as glutathione (GSH), GST, and GPx were examined by the previous methods. The status of Na+/K+, Mg2+, and Ca2+ ATPase activities was assessed using kits. The status of Na+, K+, and Ca2+ ions and inflammatory makers such as TNF-α and IL-6 were investigated using respective kits. The histopathological analysis was performed on the heart tissues to detect the histological changes.

Results

The results revealed that ponicidin increased body weight and decreased heart weight in MI rats. The status of CRP and uric acid was decreased and total protein was augmented in the ponicidin-treated MI rats. The AST, ALT, CK, and GGT activities were appreciably decreased in serum and elevated in the cardiac tissues of the ponicidin-administered MI rats. Furthermore, the ponicidin improved the antioxidant levels, decreased the TNF-α and IL-6, and regulated the Na+, K+, and Ca2+ ion transports in the MI rats. The activities of Na+/K+, Mg2+, and Ca2+ ATPase enzymes were remarkably increased in the heart tissues by the ponicidin-treated MI rats. Ponicidin treatment also ameliorated the ISO-stimulated histological alterations in the heart tissue of the MI rats.

Conclusion

Ponicidin treatment appreciably improved the antioxidants, Na+/K+, Mg2+, and Ca2+ ATPase enzyme activities, decreased the inflammatory markers, and regulated the cardiac marker enzyme activities in the MI rats. Hence, it can be a talented therapeutic candidate in the future to treat MI.

A double-edged sword: role of apoptosis repressor with caspase recruitment domain (ARC) in tumorigenesis and ischaemia/reperfusion (I/R) injury

Apoptosis repressor with caspase recruitment domain (ARC) acts as a potent and multifunctional inhibitor of apoptosis, which is mainly expressed in postmitotic cells, including cardiomyocytes. ARC is special for its N-terminal caspase recruitment domain and caspase recruitment domain. Due to the powerful inhibition of apoptosis, ARC is mainly reported to act as a cardioprotective factor during ischaemia‒reperfusion (I/R) injury, preventing cardiomyocytes from being devastated by various catastrophes, including oxidative stress, calcium overload, and mitochondrial dysfunction in the circulatory system. However, recent studies have found that ARC also plays a potential regulatory role in tumorigenesis especially in colorectal cancer and renal cell carcinomas, through multiple apoptosis-associated pathways, which remains to be explored in further studies. Therefore, ARC regulates the body and maintains the balance of physiological activities with its interesting duplex. This review summarizes the current research progress of ARC in the field of tumorigenesis and ischaemia/reperfusion injury, to provide overall research status and new possibilities for researchers.

Modulation of the miR-122/Sirt-6/ACE2 axis on experimentally-induced myocardial infarction

Myocardial infarction (MI) is a progressive myocardial necrosis that can lead to a number of life-threatening complications. MiRNAs have a crucial role in the pathogenesis of many cardiovascular diseases. Remarkably, miR-122 targets the sirtuin-6 (Sirt-6) gene, which is an essential regulator of cardiovascular function and is considered a partial angiotensin converting enzyme 2 (ACE2) activator. Modulation of this axis is supposed to contribute to MI pathogenesis. The current study aims to investigate the cardioprotective effects of xanthenone through targeting the miR-122/Sirt-6/ACE2 axis on experimentally-induced MI in rats. Xanthenone was administered for 14 days and isoprenaline was injected in the last 2 days of the experiment. Xanthenone treatment resulted in a significant downregulation of miR-122, which further upregulated Sirt-6 and thus activated the adenosine monophosphate-activated protein kinase (AMPK). AMPK increases ACE2 levels and results in a decrease in the level of its substrate angiotensin II resulting in the normalization of the inflammatory cytokines and the cardiac biomarkers. Finally, by targeting the miR-122/Sirt-6/AMPK/ACE2 axis, xanthenone has the potential to be a promising cardioprotective agent against MI.