Involvement of Nrf2 in myocardial ischemia and reperfusion injury

Nrf2 mediated signaling axis in heart failure: potential pharmacological receptor

Heart failure (HF) has emerged as the most pressing health concerns globally, and extant clinical therapies are accompanied by side effects and patients have a high burden of financial. The protein products of nuclear factor erythroid 2-related factor 2 (Nrf2) target genes have a variety of cardioprotective effects, including antioxidant, metabolic functions and anti-inflammatory. By evaluating established preclinical and clinical research in HF to date, we explored the potential of Nrf2 to exert unique cardioprotective functions as a novel therapeutic receptor for HF. In this review, we generalize the progression, structure, and function of Nrf2 research in the cardiovascular system. The mechanism of action of Nrf2 involved in HF as well as agonists of Nrf2 in natural compounds are summarized. Additionally, we discuss the challenges and implications for future clinical translation and application of pharmacology targeting Nrf2. It's critical to developing new drugs for HF.

Endothelial progenitor cell-derived extracellular vesicles: the world of potential prospects for the treatment of cardiovascular diseases

Cardiovascular diseases (CVDs) have emerged as a predominant threat to human health, surpassing the incidence and mortality rates of neoplastic diseases. Extracellular vesicles (EVs) serve as vital mediators in intercellular communication and material exchange. Endothelial progenitor cells (EPCs), recognized as precursors of vascular endothelial cells (ECs), have garnered considerable attention in recent years due to the potential therapeutic value of their derived extracellular vesicles (EPC-EVs) in the context of CVDs. This comprehensive review systematically explores the origins, characteristics, and functions of EPCs, alongside the classification, properties, biogenesis, and extraction techniques of EVs, with particular emphasis on their protective roles in CVDs. Additionally, we delve into the essential bioactive components of EPC-EVs, including microRNAs, long non-coding RNAs, and proteins, analyzing their beneficial effects in promoting angiogenesis, anti-inflammatory and anti-oxidant activities, anti-fibrosis, anti-apoptosis, and myocardial regeneration. Furthermore, this review comprehensively investigates the therapeutic potential of EPC-EVs across various CVDs, encompassing acute myocardial infarction, myocardial ischemia-reperfusion injury, atherosclerosis, non-ischemic cardiomyopathies, and diabetic cardiovascular disease. Lastly, we summarize the potential challenges associated with the clinical application of EPC-EVs and outline future directions, aiming to offer a valuable resource for both theoretical insights and practical applications of EPC-EVs in managing CVDs.

Dihydromyricetin regulates KEAP1-Nrf2 pathways to enhance the survival of ischemic flap

In clinical flap practice, there are a lot of studies being done on how to promote the survival of distal random flap necrosis in the hypoxic and ischemic state. As a traditional Chinese medicine, dihydromyricetin (DHM) is crucial in preventing oxidative stress and apoptosis in a number of disorders. In this work, we examined the impact of DHM on the ability to survive of ischemia flaps and looked into its fundamental mechanism. Our results showed that DHM significantly increased the ischemic flaps' survival area, encouraged angiogenesis and blood flow, reduced oxidative stress and apoptosis, and stimulated KEAP1-Nrf2 (Kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor) signaling pathways. Adeno-associated virus (AAV) upregulation of KEAP1 expression also negated the favorable effects of DHM on flap survival. By activating KEAP1-Nrf2 signaling pathways, DHM therapy promotes angiogenesis while reducing oxidative stress and apoptosis.

Epigallocatechin-3-gallate confers protection against myocardial ischemia/reperfusion injury by inhibiting ferroptosis, apoptosis, and autophagy via modulation of 14-3-3η

Previous studies have demonstrated that the underlying mechanisms of myocardial ischemia/reperfusion injury (MIRI) are complex and involve multiple types of regulatory cell death, including ferroptosis, apoptosis, and autophagy. Thus, we aimed to identify the mechanisms underlying MIRI and validate the protective role of epigallocatechin-3-gallate (EGCG) and its related mechanisms in MIRI. An in vivo and in vitro models of MIRI were constructed. The results showed that pretreatment with EGCG could attenuate MIRI, as indicated by increased cell viability, reduced lactate dehydrogenase (LDH) activity and apoptosis, inhibited iron overload, abnormal lipid metabolism, preserved mitochondrial function, decreased infarct size, maintained cardiac function, decreased reactive oxygen species (ROS) level, and reduced TUNEL-positive cells. Additionally, EGCG pretreatment could attenuate ferroptosis, apoptosis, and autophagy induced by MIRI via upregulating 14-3-3η protein levels. Furthermore, the protective effects of EGCG could be abolished with pAd/14-3-3η-shRNA or Compound C11 (a 14-3-3η inhibitor) but not pAd/NC-shRNA. In conclusion, EGCG pretreatment attenuated ferroptosis, apoptosis, and autophagy by mediating 14-3-3η and protected cardiomyocytes against MIRI.

An injectable polyacrylamide/chitosan-based hydrogel with highly adhesive, stretchable and electroconductive properties loaded with irbesartan for treatment of myocardial ischemia-reperfusion injury

Myocardial ischemia-reperfusion injury (MIRI) significantly contributes to the high incidence of complications and mortality associated with acute myocardial infarction. Recently, injectable electroconductive hydrogels (IECHs) have emerged as promising tools for replicating the mechanical, electroconductive, and physiological characteristics of cardiac tissue. Herein, we aimed to develop a novel IECH by incorporating irbesartan as a drug delivery system (DDS) for cardiac repair. Our approach involved merging a conductive poly-thiophene derivative (PEDOT: PSS) with an injectable dual-network adhesive hydrogel (DNAH) comprising a catechol-branched polyacrylamide network and a chitosan-hyaluronic acid covalent network. The resulting P-DNAH hydrogel, benefitting from a high conducting polymer content, a chemically crosslinked network, a robust dissipative matrix, and dynamic oxidation of catechol to quinone exhibited superior mechanical strength, desirable conductivity, and robust wet-adhesiveness. In vitro experiments with the P-DNAH hydrogel carrying irbesartan (P-DNAH-I) demonstrated excellent biocompatibility by cck-8 kit on H9C2 cells and a rapid initial release of irbesartan. Upon injection into the infarcted hearts of MIRI mouse models, the P-DNAH-I hydrogel effectively inhibited the inflammatory response and reduced the infarct size. In conclusion, our results suggest that the P-DNAH hydrogel, possessing suitable mechanical properties and electroconductivity, serves as an ideal IECH for DDS, delivering irbesartan to promote heart repair.

Aucubin alleviates doxorubicin-induced cardiotoxicity through crosstalk between NRF2 and HIPK2 mediating autophagy and apoptosis

BACKGROUND

Doxorubicin (DOX) is widely used for the treatment of a variety of cancers. However, its clinical application is limited by dose-dependent cardiotoxicity. Recent findings demonstrated that autophagy inhibition and apoptosis of cardiomyocytes induced by oxidative stress dominate the pathophysiology of DOX-induced cardiotoxicity (DIC), however, there are no potential molecules targeting on these.

PURPOSE

This study aimed to explore whether aucubin (AU) acting on inimitable crosstalk between NRF2 and HIPK2 mediated the autophagy, oxidative stress, and apoptosis in DIC, and provide a new and alternative strategy for the treatment of DIC.

METHODS AND RESULTS

We first demonstrated the protection of AU on cardiac structure and function in DIC mice manifested by increased EF and FS values, decreased serum CK-MB and LDH contents and well-aligned cardiac tissue in HE staining. Furthermore, AU alleviated DOX-induced myocardial oxidative stress, mitochondrial damage, apoptosis, and autophagy flux dysregulation in mice, as measured by decreased ROS, 8-OHdG, and TUNEL-positive cells in myocardial tissue, increased SOD and decreased MDA in serum, aligned mitochondria with reduced vacuoles, and increased autophagosomes. In vitro, AU alleviated DOX-induced oxidative stress, autophagy inhibition, and apoptosis by promoting NRF2 and HIPK2 expression. We also identified crosstalk between NRF2 and HIPK2 in DIC as documented by overexpression of NRF2 or HIPK2 reversed cellular oxidative stress, autophagy blocking, and apoptosis aggravated by HIPK2 or NRF2 siRNA, respectively. Simultaneously, AU promoted the expression and nuclear localization of NRF2 protein, which was reversed by HIPK2 siRNA, and AU raised the expression of HIPK2 protein as well, which was reversed by NRF2 siRNA. Crucially, AU did not affect the antitumor activity of DOX against MCF-7 and HepG2 cells, which made up for the shortcomings of previous anti-DIC drugs.

CONCLUSION

These collective results innovatively documented that AU regulated the unique crosstalk between NRF2 and HIPK2 to coordinate oxidative stress, autophagy, and apoptosis against DIC without compromising the anti-tumor effect of DOX in vitro.

Zhilong Huoxue Tongyu capsule improves myocardial ischemia/reperfusion injury via the PI3K/AKT/Nrf2 axis

INTRODUCTION

Zhilong Huoxue Tongyu Capsule (ZL) is a Chinese medicine used for the treatment of cardio-cerebral diseases. However, the pharmacological mechanisms underlying its regulation of myocardial ischemia/reperfusion injury (MI/RI) remain unclear.

PURPOSE

This study aims to investigate the effects and mechanisms of ZL on MI/RI in mice.

MATERIALS AND METHODS

C57BL/6J mice were randomly assigned to four groups: Sham group, I/R group, ZL group, and ZLY group. The MI/RI mouse model was established by ligation of the left anterior descending coronary artery for 30 minutes, followed by reperfusion for 120 minutes to restore blood perfusion. Cardiac function was evaluated using cardiac ultrasound. Histopathological changes and myocardial infarction area were assessed using Hematoxylin and eosin (H&E) staining and triphenyltetrazolium chloride (TTC) staining. The changes in oxidative stress- and ferroptosis-related markers were detected. RT-qPCR, Western blot, and ELISA were conducted to further explore the mechanism of ZL in improving MI/RI.

RESULTS

Our findings demonstrated that ZL exerted a protective effect against MI/RI by inhibiting ferroptosis, evidenced by the upregulation of antioxidant enzymes such as GSH and GPX4, coupled with the downregulation of ACSL4, a pro-ferroptosis factor. Furthermore, ZL positively impacted the PI3K/AKT/Nrf2 pathway by promoting ATPase activities and enhancing the relative protein expression of its components. Notably, the administration of a PI3K/AKT inhibitor reversed the antioxidant and anti-ferroptosis effects of ZL to some extent, suggesting a potential role for this pathway in mediating ZL's protective effects.

CONCLUSIONS

ZL protects against MI/RI-induced ferroptosis by modulating the PI3K/AKT signaling pathway, leading to increased Nrf2 expression and activation of the HO-1/GPX4 pathway. These findings shed light on the potential therapeutic mechanisms of ZL in the context of cardiovascular diseases.

Uncovering the Cardioprotective Potential of Diacerein in Doxorubicin Cardiotoxicity: Mitigating Ferritinophagy-Mediated Ferroptosis via Upregulating NRF2/SLC7A11/GPX4 Axis

Doxorubicin (DOX)-induced cardiotoxicity (DIC) is a life-threatening clinical issue with limited preventive approaches, posing a substantial challenge to cancer survivors. The anthraquinone diacerein (DCN) exhibits significant anti-inflammatory, anti-proliferative, and antioxidant actions. Its beneficial effects on DIC have yet to be clarified. Therefore, this study investigated DCN's cardioprotective potency and its conceivable molecular targets against DIC. Twenty-eight Wister rats were assigned to CON, DOX, DCN-L/DOX, and DCN-H/DOX groups. Serum cardiac damage indices, iron assay, oxidative stress, inflammation, endoplasmic reticulum (ER) stress, apoptosis, ferritinophagy, and ferroptosis-related biomarkers were estimated. Nuclear factor E2-related factor 2 (NRF2) DNA-binding activity and phospho-p53 immunoreactivity were assessed. DCN administration effectively ameliorated DOX-induced cardiac cytomorphological abnormalities. Additionally, DCN profoundly combated the DOX-induced labile iron pool expansion alongside its consequent lethal lipid peroxide overproduction, whereas it counteracted ferritinophagy and enhanced iron storage. Indeed, DCN valuably reinforced the cardiomyocytes' resistance to ferroptosis, mainly by restoring the NRF2/solute carrier family 7 member 11 (SLC7A11)/glutathione peroxidase 4 (GPX4) signaling axis. Furthermore, DCN abrogated the cardiac oxidative damage, inflammatory response, ER stress, and cardiomyocyte apoptosis elicited by DOX. In conclusion, for the first time, our findings validated DCN's cardioprotective potency against DIC based on its antioxidant, anti-inflammatory, anti-ferroptotic, and anti-apoptotic imprint, chiefly mediated by the NRF2/SLC7A11/GPX4 axis. Accordingly, DCN could represent a promising therapeutic avenue for patients under DOX-dependent chemotherapy.

Obacunone Alleviates Inflammatory Pain by Promoting M2 Microglial Polarization and by Activating Nrf2/HO-1 Signaling Pathway

Background

Treating inflammatory pain (IP) continues to pose clinical challenge, because of the lack of effective pharmacological interventions. Microglial polarization serves as pivotal determinant in IP progress. Obacunone (OB), a low-molecular-weight compound with a diverse array of biological functions, having reported as an activator of nuclear factor E2-related factor 2 (Nrf2), exhibits anti-inflammatory property. However, it remains uncertain whether OB can alleviate IP by facilitating the transition of microglial polarization from the M1 to M2 state through modulating Nrf2/ heme oxygenase-1 (HO-1) pathway.

Methods

We induced an mice IP model by subcutaneously administering Complete Freund's Adjuvant (CFA) into the hind paw. Paw withdrawal latency (PWL) in seconds (s) and paw withdrawal frequency (PWF) were employed to evaluate the establishment of the IP model, while a caliper was used to measure the maximal dorsoventral thickness of the mice paw. Nerve injury was assessed by Hematoxylin-Eosin (HE) Staining. Western blot and got conducted for detection of M1/M2 microglial polarization markers, Nrf2 and HO-1 in spinal cord tissues respectively.

Results

In comparison to the control cohort, PWF, M1 phenotype marker iNOS, CD86, paw thickness increased significantly within CFA cohort, while PWL, M2 phenotype marker Arg-1, interleukin-10 (IL-10) decreased in the CFA group. In comparison to model cohort, OB treatment decreased PWF, paw thickness, M1 phenotype marker iNOS, CD86 significantly, while PWL, M2 phenotype marker Arg-1, IL-10, Nrf2, HO-1 increased significantly. The morphological injuries of sciatic nerve in CFA mice were obviously improved by OB treatment. OB inhibited the release of M1-related IL-1β, CXCL1 but promoted M2-related TGF-β, IL-10 in serum in CFA mice. The intervention of the Nrf2 inhibitor ML385 mitigated analgesic effect of OB.

Conclusion

We demonstrate that OB is able to attenuate inflammatory pain via promoting microglia polarization from M1 to M2 and enhancing Nrf2/HO-1 signal. OB treatment may be a potential alternative agent in the treatment of IP.

LncRNA SNHG1 alleviates myocardial ischaemia-reperfusion injury by regulating the miR-137-3p/KLF4/TRPV1 axis

AIMS

Myocardial ischaemia-reperfusion injury (MIRI) contributes to serious myocardial injury and even death. Long non-coding RNAs (lncRNAs) have been reported to play pivotal roles in the occurrence and development of MIRI. Here, the detailed molecular mechanism of lncRNA SNHG1 in MIRI was explored.

METHODS AND RESULTS

A cell model of MIRI was established through hypoxia/reoxygenation (H/R) stimulation. Cell viability and pyroptosis were evaluated utilizing MTT, PI staining, and flow cytometry. Interleukin (IL)-1β and IL-18 secretion levels were examined by ELISA. The gene and protein expression were detected by RT-qPCR and western blot, respectively. Dual luciferase reporter gene, RIP and ChIP assays were performed to analyse the molecular interactions. The results showed that lncRNA SNHG1 overexpression alleviated H/R-induced HL-1 cell pyroptosis (all P < 0.05). LncRNA SNHG1 promoted KLF4 expression by sponging miR-137-3p. miR-137-3p silencing alleviated H/R-induced pyroptosis in HL-1 cells (all P < 0.05), which was abolished by KLF4 knockdown (all P < 0.05). KLF4 activated the AKT pathway by transcriptionally activating TRPV1 in HL-1 cells (all P < 0.05). TRPV1 knockdown reversed the alleviation of SNHG1 upregulation on H/R-induced pyroptosis in HL-1 cells (all P < 0.05).

CONCLUSIONS

These results showed that lncRNA SNHG1 assuaged cardiomyocyte pyroptosis during MIRI progression by regulating the KLF4/TRPV1/AKT axis through sponging miR-137-3p. Our findings may provide novel therapeutic targets for MIRI.

Therapeutic Role of Chinese Medicine Targeting Nrf2/HO-1 Signaling Pathway in Myocardial Ischemia/Reperfusion Injury

Acute myocardial infarction (AMI), characterized by high incidence and mortality rates, poses a significant public health threat. Reperfusion therapy, though the preferred treatment for AMI, often exacerbates cardiac damage, leading to myocardial ischemia/reperfusion injury (MI/RI). Consequently, the development of strategies to reduce MI/RI is an urgent priority in cardiovascular therapy. Chinese medicine, recognized for its multi-component, multi-pathway, and multi-target capabilities, provides a novel approach for alleviating MI/RI. A key area of interest is the nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. This pathway is instrumental in regulating inflammatory responses, oxidative stress, apoptosis, endoplasmic reticulum stress, and ferroptosis in MI/RI. This paper presents a comprehensive overview of the Nrf2/HO-1 signaling pathway's structure and its influence on MI/RI. Additionally, it reviews the latest research on leveraging Chinese medicine to modulate the Nrf2/HO-1 pathway in MI/RI treatment.

4-octyl itaconate protects against oxidative stress-induced liver injury by activating the Nrf2/Sirt3 pathway through AKT and ERK1/2 phosphorylation

4-octyl itaconate (4-OI) is a cell-permeable itaconate derivative with anti-inflammatory and antioxidant properties. However, its therapeutic potential for oxidative stress-induced liver injury remains unknown. This study investigated the hepatoprotective effects and mechanisms of 4-OI against oxidative damage in in vitro and in vivo models. 4-OI attenuated H2O2-induced cytotoxicity, oxidative stress, and mitochondrial dysfunction in L02 and HepG2 cells. Untargeted metabolomics profiling and pathway analysis identified the PI3K/AKT/mTOR and MAPK pathways as key regulators of 4-OI's protective effects. Specifically, 4-OI induced phosphorylation of AKT and ERK1/2, leading to activation of the Nrf2 signaling pathway. Nrf2 upregulated expression of the mitochondrial deacetylase Sirt3, which subsequently alleviated H2O2-induced cell injury. In mice, 4-OI reduced acetaminophen (APAP)-induced liver injury as evidenced by attenuated hepatocellular necrosis and decreased serum liver enzymes. It also elevated hepatic expression of Nrf2, Sirt3, p-AKT and p-ERK1/2. Inhibition of AKT, ERK1/2 or Nrf2 blocked the protective effects of 4-OI in vitro, suggesting its antioxidant activity is mediated by activating the Nrf2/Sirt3 pathway via AKT and ERK1/2 phosphorylation. In summary, 4-OI exerted antioxidant and hepatoprotective effects by activating the Nrf2/Sirt3 signaling pathway through AKT and ERK1/2 phosphorylation, which were elucidated using in vitro and in vivo oxidative stress models. This provides novel insights into the mechanisms of 4-OI against oxidative stress-related liver diseases.

Cinnamaldehyde protects cardiomyocytes from oxygen-glucose deprivation/reoxygenation-induced lipid peroxidation and DNA damage via activating the Nrf2 pathway

Rapid restoration of perfusion in ischemic myocardium is the most direct and effective treatment for coronary heart disease but may cause myocardial ischemia/reperfusion injury (MIRI). Cinnamaldehyde (CA, C9H8O), a key component in the well-known Chinese medicine cinnamomum cassia, has cardioprotective effects against MIRI. This study aimed to observe the therapeutic effect of CA on MIRI and to elucidate its potential mechanism. H9C2 rat cardiomyocytes were pretreated with CA solution at 0, 10, and 100 μM, respectively and subjected to oxygen-glucose deprivation/reoxygenation (OGD/R). Then the cell viability, the NF-κB and caspase3 gene levels, the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio, superoxide dismutase (SOD) level, reactive oxygen species (ROS) generation, 4-hydroxynonenal (4-HNE), and malondialdehyde (MDA) were detected. The severity of DNA damage was assessed by tail moment (TM) values using alkaline comet assay. Besides, the DNA damage-related proteins and the key proteins of the Nrf2 pathway were detected by western blot. CA treatment increased the cell viability, GHS/GSSG ratio, SOD level, PARP1, Nrf2, PPAR-γ, and HO-1 protein levels of H9C2 cardiomyocytes, while reducing NF-κB, caspase3, ROS level, 4-HNE and MDA content, γ-H2AX protein level, and TM values. Inhibition of the Nrf2 pathway reversed the effect of CA on cell viability and apoptosis of OGD/R induced H9C2 cardiomyocytes. Besides, 100 μM CA was more effective than 10 μM CA. In the OGD/R-induced H9C2 cardiomyocyte model, CA can protect cardiomyocytes from MIRI by attenuating lipid peroxidation and repairing DNA damage. The mechanism may be related to the activation of the Nrf2 pathway.

The Research Progress of Mitochondrial Transplantation in the Treatment of Mitochondrial Defective Diseases

Mitochondria are double-membrane organelles that are involved in energy production, apoptosis, and signaling in eukaryotic cells. Several studies conducted over the past decades have correlated mitochondrial dysfunction with various diseases, including cerebral ischemia, myocardial ischemia-reperfusion, and cancer. Mitochondrial transplantation entails importing intact mitochondria from healthy tissues into diseased tissues with damaged mitochondria to rescue the injured cells. In this review, the different mitochondrial transplantation techniques and their clinical applications have been discussed. In addition, the challenges and future directions pertaining to mitochondrial transplantation and its potential in the treatment of diseases with defective mitochondria have been summarized.

Nrf2 for a key member of redox regulation: A novel insight against myocardial ischemia and reperfusion injuries

Nuclear factor erythroid-2 related factor 2 (Nrf2), a nuclear transcription factor, modulates genes responsible for antioxidant responses against toxic and oxidative stress to maintain redox homeostasis and participates in varieties of cellular processes such as metabolism and inflammation during myocardial ischemia and reperfusion injuries (MIRI). The accumulation of reactive oxygen species (ROS) from damaged mitochondria, xanthine oxidase, NADPH oxidases, and inflammation contributes to depraved myocardial ischemia and reperfusion injuries. Considering that Nrf2 played crucial roles in antagonizing oxidative stress, it is reasonable to delve into the up or down-regulated molecular mechanisms of Nrf2 in the progression of MIRI to provide the possibility of new therapeutic medicine targeting Nrf2 in cardiovascular diseases. This review systematically describes the generation of ROS, the regulatory metabolisms of Nrf2 as well as several natural or synthetic compounds activating Nrf2 during MIRI, which might provide novel insights for the anti-oxidative stress and original ideas targeting Nrf2 for the prevention and treatment in cardiovascular diseases.

Huoxin Pill Reduces Myocardial Ischemia Reperfusion Injury in Rats via TLR4/NFκB/NLRP3 Signaling Pathway

OBJECTIVE

To explore the protective effect of Huoxin Pill (HXP) on acute myocardial ischemia-reperfusion (MIRI) injury in rats.

METHODS

Seventy-five adult SD rats were divided into the sham-operated group, model group, positive drug group (diltiazem hydrochloride, DH), high dose group (24 mg/kg, HXP-H) and low dose group (12 mg/kg, HXP-L) of Huoxin Pill (n=15 for every group) according to the complete randomization method. After 1 week of intragastric administration, the left anterior descending coronary artery of the rat's heart was ligated for 45 min and reperfused for 3 h. Serum was separated and the levels of creatine kinase (CK), creatine kinase isoenzyme (CK-MB) and lactate dehydrogenase (LDH), superoxide dismutase (SOD), and malondialdehyde (MDA), hypersensitive C-reactive protein (hs-CRP) and interleukin-1β (IL-1β) were measured. Myocardial ischemia rate, myocardial infarction rate and myocardial no-reflow rate were determined by staining with Evans blue and 2,3,5-triphenyltetrazolium chloride (TTC). Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and Bioinformatics Analysis Tool for Molecular mechANism of Traditional Chinese Medicine (BATMAN) databases were used to screen for possible active compounds of HXP and their potential therapeutic targets; the results of anti-inflammatory genes associated with MIRI were obtained from GeneCards, Drugbank, Online Mendelian Inheritance in Man (OMIM), and Therapeutic Target Datebase (TTD) databases was performed; Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were used to analyze the intersected targets; molecular docking was performed using AutoDock Tools. Western blot was used to detect the protein expression of Toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NFκB)/NOD-like receptor protein 3 (NLRP3).

RESULTS

Compared with the model group, all doses of HXP significantly reduced the levels of LDH, CK and CK-MB (P<0.05, P<0.01); HXP significantly increased serum activity of SOD (P<0.05, P<0.01); all doses of HXP significantly reduced the levels of hs-CRP and IL-1β (P<0.05, P<0.01) and the myocardial infarction rate and myocardial no-reflow rate (P<0.01). GO enrichment analysis mainly involved positive regulation of gene expression, extracellular space and identical protein binding, KEGG pathway enrichment mainly involved PI3K-Akt signaling pathway and lipid and atherosclerosis. Molecular docking results showed that kaempferol and luteolin had a better affinity with TLR4, NFκB and NLRP3 molecules. The protein expressions of TLR4, NFκB and NLRP3 were reduced in the HXP group (P<0.01).

CONCLUSIONS

HXP has a significant protective effect on myocardial ischemia-reperfusion injury in rats, and its effect may be related to the inhibition of redox response and reduction of the inflammatory response by inhibiting the TLR4NFκB/NLRP3 signaling pathway.

Curcumin alleviates bisphenol AF-induced oxidative stress and apoptosis in caprine endometrial epithelial cells via the Nrf2 signaling pathway

Bisphenol AF (BPAF), a BPA-substitute, has been widely used in industrial compounds throughout the world. Several studies have shown that BPAF has endocrine interference and reproductive toxicity. However, the toxic effects of BPAF on pregnancy and placenta of goats are still unclear. Therefore, the objective of this study was to reveal the toxic effect of BPAF by using an in vitro culture model of caprine endometrial epithelial cells (EECs) and further attempted to alleviate the toxicity by curcumin pretreatment. The results showed that BPAF induces significant effects on EECs, including decreased cell viability and mitochondrial membrane potential (△ψm), elevating intracellular reactive oxygen species (ROS), promoting cell apoptosis through upregulating the expression of Bax, Cytochrome c, and downregulating the expression of Bcl-2. Meanwhile, BPAF induced dysregulation of oxidative stress by increasing the levels of malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) but decreasing the activities of superoxide dismutase (SOD). However, curcumin pretreatment could significantly attenuate BPAF-induced toxic effects in EECs. Further study revealed that BPAF treatment could activate mitogen-activated protein kinase (MAPK) pathway and nuclear factor-erythroid 2-related factor 2 (Nrf2) expression, but curcumin pretreatment significantly inhibited the activation of MAPK signal pathway and Nrf2 expression induced by BPAF. Overall, this study indicated that curcumin could prevent BPAF-induced EECs cytotoxicity, which provides a potential therapeutic strategy for female infertility associated with BPAF exposure.

Dexmedetomidine postconditioning attenuates myocardial ischemia/reperfusion injury by activating the Nrf2/Sirt3/SOD2 signaling pathway in the rats

OBJECTIVES

To observe the protective effects of dexmedetomidine (Dex) postconditioning on myocardial ischemia/reperfusion injury (IRI) and to explore its potential molecular mechanisms.

METHODS

One-hundred forty-seven male Sprague-Dawley rats were randomly divided into five groups receiving the different treatments: Sham, ischemia/reperfusion (I/R), Dex, Brusatol, Dex + Brusatol. By the in vivo rat model of myocardial IRI, cardioprotective effects of Dex postconditioning were evaluated by assessing serum CK-MB and cTnI levels, myocardial HE and Tunel staining and infarct size. Furthermore, the oxidative stress-related markers including intracellular ROS level, myocardial tissue MDA level, SOD and GSH-PX activities were determined.

RESULTS

Dex postconditioning significantly alleviated myocardial IRI, decreased intracellular ROS and myocardial tissue MDA level, increased SOD and GSH-PX activities. Dex postconditioning significantly up-regulated myocardial expression of Bcl-2, down-regulated Bax and cleaved caspase-3 and decreased cardiomyocyte apoptosis rate. furthermores, Dex postconditioning promoted Nrf2 nuclear translocation, increased myocardial expression of Sirt3 and SOD2 and decreased Ac-SOD2. However, brusatol reversed cardioprotective benefits of Dex postconditioning, significantly decreased Dex-induced Nrf2 nuclear translocation and reduced myocardial expression of Sirt3 and SOD2.

CONCLUSIONS

Dex postconditioning can alleviate myocardial IRI by suppressing oxidative stress and apoptosis, and these beneficial effects are at least partly mediated by activating the Nrf2/Sirt3/SOD2 signaling pathway.

The protective effects of uric acid against myocardial ischemia via the Nrf2 pathway

Uric acid (UA) possesses both pro- and anti-oxidative properties in ischemic heart disease, but the underlying mechanism remains unclear. We aimed to investigate UA's protective effect on myocardial ischemia by examining its effects on ECG Ischemic Alterations (EIA) and H2O2-induced oxidative stress in H9C2 myocardial cells. The incidence of EIA decreased over time and was more prevalent among women than men. A U-shaped relationship was observed between UA levels and EIA incidence, with the third quartile exhibiting a protective association. Addition of 237.9 μmol/L UA improved cellular damage and oxidative stress in H2O2-treated H9C2 cells, as determined by cell viability, LDH release, ROS levels, and total antioxidant capacity assays. UA activated the Nrf2 pathway, evidenced by increased expression of Nrf2, GCLC, and HO-1 proteins. By reversing cell cycle blockage, promoting wound healing ability, improving colony-forming capacity, and increasing angiogenesis in H2O2-treated cells, UA exhibited positive effects on cardiomyocyte growth characteristics. Additionally, use of Nrf2 inhibitor ML385 confirmed the involvement of the Nrf2 pathway by negating UA's effects on oxidatively damaged cardiomyocytes. Our findings suggest that UA induces downstream antioxidant factors to ameliorate oxidative stress by activating the Nrf2 pathway, which could be one of the targets responsible for UA's beneficial effects in myocardial ischemia.

Dexmedetomidine combined with propofol attenuates myocardial ischemia/reperfusion injury by activating the AMPK signaling pathway

Objective

Myocardial ischemia/reperfusion (MI/R) injury is a major cause of cardiac tissue damage, with high disability and death rates. Although both dexmedetomidine (Dex) and propofol (PPF) have been indicated to alleviate MI/R injury in rat models, the effects of the combined use of these two drugs remain unclear. This study aimed to investigate the combined effects of Dex and PPF against MI/R injury and related mechanisms.

Methods

A rat model of MI/R injury was established and used to explore the combined effects of Dex and PPF on MI/R injury. Hematoxylin-eosin (HE) and Masson staining were used for histopathological evaluation. 2,3,5-triphenyltetrazolium chloride (TTC), echocardiography, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining were used to determine myocardial infarction size, cardiac function, and apoptosis, respectively. Enzyme-linked immunosorbent assay (ELISA) was performed to assess myocardial function and oxidative stress (OS). Autophagy was observed through transmission electron microscopy. Moreover, western blotting was conducted to detect autophagy markers and the AMPK pathway.

Results

The combination of Dex and PPF alleviated histopathological injury, reduced myocardial infarction, and rescued cardiac dysfunction in MI/R rats. Furthermore, Dex combined with PPF decreased the levels of MDA and ROS and increased the SOD level in MI/R rats. Besides, Dex combined with PPF inhibited myocardial apoptosis in MI/R rats. After combined treatment with Dex and PPF, the number of autophagosomes, expression levels of Beclin-1 and LC3II/LC3I were elevated, while the expression levels of p62 were reduced in MI/R rats. The combined use of Dex and PPF activated the AMPK pathway in MI/R rats. Compound C (an AMPK inhibitor) could abolish the combined effects of Dex and PPF on alleviating myocardial injury and enhancing autophagy in MI/R rats.

Conclusion

The combination of Dex and PPF attenuated MI/R injury in rats, which may be associated with the activation of the AMPK signaling pathway.

Astragalin: a food-origin flavonoid with therapeutic effect for multiple diseases

Naturally occurring flavonoids have long been utilized as essential templates for the development of novel drugs and as critical ingredients for functional foods. Astragalin (AG) is a natural flavonoid that can be isolated from a variety of familiar edible plants, such as the seeds of green tea, Morus alba L., and Cuscuta chinensis. It is noteworthy that AG has a wide range of pharmacological activities and possesses therapeutic effects against a variety of diseases, covering cancers, osteoarthritis, osteoporosis, ulcerative colitis, mastitis, obesity, diabetes mellitus, diabetic complications, ischemia/reperfusion injury, neuropathy, respiratory diseases, and reproductive system diseases. This article reviewed the natural source and pharmacokinetics of AG and systematically summarized the pharmacological activities and potential mechanisms of AG in treating diverse diseases in order to promote the development of AG as a functional food, in doing so providing references for its clinical application in disease therapy.

16α-OHE1, a novel oestrogen metabolite, attenuates dysfunction of left ventricle contractility via regulation of autophagy after myocardial ischemia and reperfusion

BACKGROUND

Myocardial ischemia-reperfusion (MI/R) can exacerbate the initial cardiac damage in the myocardial functional changes, including dysfunction of left ventricular contractility. Oestrogen has been proven to protect the cardiovascular system. However, whether the oestrogen or its metabolites play the main role in attenuating dysfunction of left ventricular contractility is unknown.

METHODS AND RESULTS

This study used the LC-MS/MS to detect oestrogen and its metabolites in clinical serum samples (n = 62) with heart diseases. After correlation analysis with markers of myocardial injury including cTnI (P < 0.01), CK-MB (P < 0.05), and D-Dimer (P < 0.001), 16α-OHE1 was identified. The result from LC-MS/MS in female and ovariectomised (OVX) rat serum samples (n = 5) matched the findings in patients. In MI/R model of animal, the recovery of left ventricular developed pressure (LVDP), rate pressure product (RPP), dp/dtmax and dp/dtmin after MI/R in OVX or male group were worsened than those in female group. Also, the infarction area of OVX or male group was larger than that in females (n = 5, p < 0.01). Furthermore, LC3 II in the left ventricle of OVX and male group was lower than that in females (n = 5, p < 0.01) by immunofluorescence. In H9C2 cells, after the application of 16α-OHE1, the number of autophagosomes was further increased and other organelles improved in MI/R. Simultaneously, LC3 II, Beclin1, ATG5, and p-AMPK/AMPK were increased, and p-mTOR/mTOR was decreased (n = 3, p < 0.01) by Simple Western.

CONCLUSION

16α-OHE1 could attenuate left ventricle contractility dysfunction via autophagy regulation after MI/R, which also offered fresh perspectives on therapeutical treatment for attenuating MI/R injury.

The role of PI3K/AKT signaling pathway in myocardial ischemia-reperfusion injury

Myocardial ischemia has a high incidence and mortality rate, and reperfusion is currently the standard intervention. However, reperfusion may lead to further myocardial damage, known as myocardial ischemia/reperfusion injury (MIRI). There are currently no effective clinical treatments for MIRI. The PI3K/Akt signaling pathway is involved in cardiovascular health and disease and plays an important role in reducing myocardial infarct size and restoring cardiac function after MIRI. Activation of the PI3K/Akt pathway provides myocardial protection through synergistic upregulation of antioxidant, anti-inflammatory, and autophagy activities and inhibition of mitochondrial dysfunction and cardiomyocyte apoptosis. Many studies have shown that PI3K/Akt has a significant protective effect against MIRI. Here, we reviewed the molecular regulation of PI3K/Akt in MIRI and summarized the molecular mechanism by which PI3K/Akt affects MIRI, the effects of ischemic preconditioning and ischemic postconditioning, and the role of related drugs or activators targeting PI3K/Akt in MIRI, providing novel insights for the formulation of myocardial protection strategies. This review provides evidence of the role of PI3K/Akt activation in MIRI and supports its use as a therapeutic target.

Broadening horizons: The role of ferroptosis in myocardial ischemia-reperfusion injury

Ferroptosis is a novel type of regulated cell death (RCD) discovered in recent years, where abnormal intracellular iron accumulation leads to the onset of lipid peroxidation, which further leads to the disruption of intracellular redox homeostasis and triggers cell death. Iron accumulation with lipid peroxidation is considered a hallmark of ferroptosis that distinguishes it from other RCDs. Myocardial ischemia-reperfusion injury (MIRI) is a process of increased myocardial cell injury that occurs during coronary reperfusion after myocardial ischemia and is associated with high post-infarction mortality. Multiple experiments have shown that ferroptosis plays an important role in MIRI pathophysiology. This review systematically summarized the latest research progress on the mechanisms of ferroptosis. Then we report the possible link between the occurrence of MIRI and ferroptosis in cardiomyocytes. Finally, we discuss and analyze the related drugs that target ferroptosis to attenuate MIRI and its action targets, and point out the shortcomings of the current state of relevant research and possible future research directions. It is hoped to provide a new avenue for improving the prognosis of the acute coronary syndrome.

Stachydrine ameliorates hypoxia reoxygenation injury of cardiomyocyte via enhancing SIRT1-Nrf2 pathway

BACKGROUND

Hypoxia/reoxygenation (H/R)-induced cardiomyocyte cell apoptosis is critical in developing myocardial infarction. Stachydrine (STA), an active constituent of Leonurus heterophyllus sweet, could have a protective effect on myocardial H/R injury, which remains unexplored. Therefore, the study aimed to investigate the protective effects and mechanisms of STA on H/R injury of cardiomyocytes.

METHODS

Rat cardiomyocyte H9c2 cells underwent H/R (hypoxia for 4 h and reoxygenation for 12 h). Cells were pretreated with STA (50 µM) 2 h before H/R. Cardiomyocyte injury was evaluated by CCK-8 assay and lactate dehydrogenase (LDH) release. Apoptosis was assessed by TUNEL staining and caspase-3 activity. Oxidative stress was assessed by lipid oxidation product MDA and a ROS-scavenging enzyme SOD in culture media. Western blot was performed to measure the protein expressions of SIRT1, Nrf2, and heme oxygenase-1 (HO-1).

RESULTS

STA reversed the decrease in cell viability and increased LDH release in H9c2 cells with the H/R insult. STA significantly suppressed oxidative stress, reduced MDA content, and increased SOD activity in H9c2 cells exposed to H/R. STA reduced apoptosis in H9c2 cells exposed to H/R, as evidenced by the reduced TUNEL positive cells and caspase-3 activity. In addition, STA enhanced SIRT1, Nrf2, and HO-1 protein expression in H/R-stimulated H9c2 cells. SIRT1 and Nrf2 involved the protective effect of STA in H/R-exposed H9c2 cells, as the changes in cell viability and caspase-3 activity by STA can be reversed by SIRT1 inhibitor EX-527 or Nrf2 siRNA.

CONCLUSIONS

Our data speculated that STA protects H/R injury and inhibits oxidative stress and apoptosis in cardiomyocytes by activation of the SIRT1-Nrf2 pathway.

7-Hydroxy Frullanolide Ameliorates Isoproterenol-Induced Myocardial Injury through Modification of iNOS and Nrf2 Genes

Myocardial infarction (MI) is the principal cause of premature death. Protecting myocardium from ischemia is the main focus of intense research. 7-hydroxy frullanolide (7-HF) is a potent anti-inflammatory agent, showing its efficacy in different acute and chronic inflammatory disorders such as atherosclerosis, suggesting it can be a potential cardioprotective agent. For the induction of MI, Sprague-Dawley rats (n = 5) were administered isoproterenol (ISO) 85 mg/kg s.c at 24 h intervals for two days. The potential cardioprotective effect of 7-HF and its mechanisms were explored by in vivo and in vitro methods. 7-HF significantly prevented the extent of myocardial injury by decreasing the infarct size, preserving the histology of myocardial tissue, and reducing the release of cardiac biomarkers. Further, 7-HF increased the mRNA expression of cardioprotective gene Nrf2 and reduced the mRNA expression of iNOS. 7-HF also improved cardiac function by decreasing the cardiac workload through its negative chronotropic and negative ionotropic effect, as well as by reducing peripheral vascular resistance due to the inhibition of voltage-dependent calcium channels and the release of calcium from intracellular calcium stores. In conclusion, 7-HF showed cardioprotective effects in the MI model, which might be due to modulating the expression of iNOS and Nrf2 genes as well as improving cardiac functions.

Dexmedetomidine abates myocardial ischemia reperfusion injury through inhibition of pyroptosis via regulation of miR-665/MEF2D/Nrf2 axis

The current study intended to delve into the mechanisms of dexmedetomidine (Dex) in regulating myocardial pyroptosis against myocardial ischemia/reperfusion injury (MIRI). The rat MIRI models were induced by ligation/release of the coronary artery in vivo and Langendorff perfusion ex vivo. Hemodynamic parameters, infarction sizes, and histopathological changes were assessed to understand the effects of Dex on MIRI. We explored the mechanisms through functional experiments on an H9c2 cell hypoxia/reoxygenation (H/R) model. Cell viability and apoptosis were evaluated using cell counting kit 8 (CCK-8) and AV/PI dual staining respectively. The expressions of miR-665 and MEF2D mRNA were detected by qRT-PCR. Western blot was employed to determine the expression levels of pyroptosis- and signaling pathway- related proteins. The interplays between miR-665 and MEF2D were validated by Dual-luciferase reporter assays. Our findings indicated that Dex preconditioning dramatically attenuated hemodynamic derangements, infarct size, and histopathological damage in rats undergoing MIRI. Dex markedly augmented cell viability, while suppressing cell apoptosis and expressions of NLRP3, cleaved-caspase-1, ASC, GSDMD, IL-1β, and IL-18 in H9c2 cells subjected to H/R injury. MiR-665 was significantly upregulated, MEF2D and Nrf2 downregulated following H/R, whereas Dex preconditioning reversed these changes. MEF2D was validated to be a target gene of miR-665. Overexpression of miR-665 decreased the expression of MEF2D and blunted the protective effects of Dex in H9c2 cells. Moreover, the functional rescue experiment further verified that Dex regulated MEF2D/Nrf2 pathway via miR-665. In conclusion, Dex mitigates MIRI through inhibiting pyroptosis via regulating miR-665/MEF2D/Nrf2 axis.

A review of how the saffron (Crocus sativus) petal and its main constituents interact with the Nrf2 and NF-κB signaling pathways

The primary by-product of saffron (Crocus sativus) processing is saffron petals, which are produced in large quantities but are discarded. The saffron petals contain a variety of substances, including alkaloids, anthocyanins, flavonoids, glycosides, kaempferol, and minerals. Pharmacological investigations revealed the antibacterial, antidepressant, antidiabetic, antihypertensive, antinociceptive, antispasmodic, antitussive, hepatoprotective, immunomodulatory, and renoprotective properties of saffron petals, which are based on their antioxidant, anti-inflammatory, and antiapoptotic effects. The nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway protects against oxidative stress, carcinogenesis, and inflammation. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-ĸB) is a protein complex involved in approximately all animal cells and participates in different biological procedures such as apoptosis, cell growth, development, deoxyribonucleic acid (DNA) transcription, immune response, and inflammation. The pharmacological properties of saffron and its compounds are discussed in this review, along with their associated modes of action, particularly the Nrf2 and NF-ĸB signaling pathways. Without considering a time constraint, our team conducted this review using search engines or electronic databases like PubMed, Scopus, and Web of Science. Saffron petals and their main constituents may have protective effects in numerous organs such as the brain, colon, heart, joints, liver, lung, and pancreas through several mechanisms, including the Nrf2/heme oxygenase-1 (HO-1)/Kelch-like ECH-associated protein 1 (Keap1) signaling cascade, which would then result in its antioxidant, anti-inflammatory, antiapoptotic, and therapeutic effects.

Nanomedicine-Based Therapeutics for Myocardial Ischemic/Reperfusion Injury

Myocardial ischemic/reperfusion (IR) injury is a global cardiovascular disease with high mortality and morbidity. Therapeutic interventions for myocardial ischemia involve restoring the occluded coronary artery. However, reactive oxygen species (ROS) inevitably impair the cardiomyocytes during the ischemic and reperfusion phases. Antioxidant therapy holds great promise against myocardial IR injury. The current therapeutic methodologies for ROS scavenging depend predominantly on administering antioxidants. Nevertheless, the intrinsic drawbacks of antioxidants limit their further clinical transformation. The use of nanoplatforms with versatile characteristics greatly benefits drug delivery in myocardial ischemic therapy. Nanoplatform-mediated drug delivery significantly improves drug bioavailability, increases therapeutic index, and reduces systemic toxicity. Nanoplatforms can be specifically and reasonably designed to enhance molecule accumulation at the myocardial site. The present review initially summarizes the mechanism of ROS generation during the process of myocardial ischemia. The understanding of this phenomenon will facilitate the advancement of innovative therapeutic strategies against myocardial IR injury. The latest developments in nanomedicine for treating myocardial ischemic injury are then discussed. Finally, the current challenges and perspectives in antioxidant therapy for myocardial IR injury are addressed.

Potentilla reptans L. preconditioning regulates H19 and MIAT long noncoding RNAs in H9C2 myoblasts Ischemia/Reperfusion model

The present study aimed to evaluate the effect of the ethyl acetate fraction of P. reptans root (PEF) preconditioning on expressions of lncRNAs H19 and MIAT in H9C2 myoblasts I/R injury.H9C2 cells were treated with different concentrations ranging from (10-400 µg/ml) of PEF for 24 h, followed by simulation of I/R condition. For I/R experiments, H9C2 cells were subjected with the oxygen and glucose deprivation for 2 h.H9C2 cell viability was significantly enhanced by PEF preconditioning under I/R condition in a concentration-dependent manner up to 200 µg/ml as a EC₅₀. The PEF significantly diminished the expression of lncRNA MIAT and rate of apoptosis against the I/R group. In addition, PEF pretreated before stimulation I/R condition increased H19 expression compared to the normal PEF group with no statistically significant differences between groups. Hence, the results suggest that PEF can protect cardiomyocytes during hypoxia-induced myocardial cell injury by targeting specific involved genes.

Ursolic acid reduces oxidative stress injury to ameliorate experimental autoimmune myocarditis by activating Nrf2/HO-1 signaling pathway

Background: Oxidative stress is crucial in experimental autoimmune myocarditis (EAM)-induced inflammatory myocardial injury. Ursolic acid (UA) is an antioxidant-enriched traditional Chinese medicine formula. The present study aimed to investigate whether UA could alleviate inflammatory cardiac injury and determine the underlying mechanisms. Methods: Six-week-old male BALB/c mice were randomly assigned to one of the three groups: Sham, EAM group, or UA intervention group (UA group) by gavage for 2 weeks. An EAM model was developed by subcutaneous injection of α-myosin heavy chain derived polypeptide (α-MyHC peptide) into lymph nodes on days 0 and 7. Echocardiography was used to assess cardiac function on day 21. The inflammation level in the myocardial tissue of each group was compared using hematoxylin and eosin staining (HE) of heart sections and Interleukin-6 (IL-6) immunohistochemical staining. Masson staining revealed the degree of cardiac fibrosis. Furthermore, Dihydroethidium staining, Western blot, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) were used to determine the mechanism of cardioprotective effects of UA on EAM-induced cardiac injury, and the level of IL-6, Nrf2, and HO-1. Results: In EAM mice, UA intervention significantly reduced the degree of inflammatory infiltration and myocardial fibrosis while improving cardiac function. Mechanistically, UA reduced myocardial injury by inhibiting oxidative stress (as demonstrated by a decrease of superoxide and normalization of pro- and antioxidant enzyme levels). Interestingly, UA intervention upregulated the expression of antioxidant factors such as Nrf2 and HO-1. In vitro experiments, specific Nrf2 inhibitors reversed the antioxidant and antiapoptotic effects of ursolic acid, which further suggested that the amelioration of EAM by UA was in a Nrf2/HO-1 pathway-dependent manner. Conclusion: These findings indicate that UA is a cardioprotective traditional Chinese medicine formula that reduces EAM-induced cardiac injury by up-regulating Nrf2/HO-1 expression and suppressing oxidative stress, making it a promising therapeutic strategy for the treatment of EAM.

Influences of dexmedetomidine on stress responses and postoperative cognitive and coagulation functions in patients undergoing radical gastrectomy under general anesthesia

BACKGROUND

Radical gastrectomy (RG) is commonly used in the treatment of patients with gastric cancer (GC), but this procedure may lead to stress responses, postoperative cognitive dysfunction, and blood coagulation abnormalities in patients.

AIM

To investigate the influences of dexmedetomidine (DEX) on stress responses and postoperative cognitive and coagulation functions in patients undergoing RG under general anesthesia (GA).

METHODS

One hundred and two patients undergoing RG for GC under GA from February 2020 to February 2022 were retrospectively reviewed. Of these, 50 patients had received conventional anesthesia intervention [control group (CG)] and 52 patients had received DEX in addition to routine anesthesia intervention [observation group (OG)]. Inflammatory factor (IFs; tumor necrosis factor-α, TNF-α; interleukin-6, IL-6), stress responses (cortisol, Cor; adrenocorticotropic hormone, ACTH), cognitive function (CF; Mini-Mental State Examination, MMSE), neurological function (neuron-specific enolase, NSE; S100 calcium-binding protein B, S100B), and coagulation function (prothrombin time, PT; thromboxane B2, TXB2; fibrinogen, FIB) were compared between the two groups before surgery (T0), as well as at 6 h (T1) and 24 h (T2) after surgery.

RESULTS

Compared with T0, TNF-α, IL-6, Cor, ACTH, NSE, S100B, PT, TXB2, and FIB showed a significant increase in both groups at T1 and T2, but with even lower levels in OG vs CG. Both groups showed a significant reduction in the MMSE score at T1 and T2 compared with T0, but the MMSE score was notably higher in OG compared with CG.

CONCLUSION

In addition to a potent inhibitory effect on postoperative IFs and stress responses in GC patients undergoing RG under GA, DEX may also alleviate the coagulation dysfunction and improve the postoperative CF of these patients.

H1N1 influenza virus infection through NRF2-KEAP1-GCLC pathway induces ferroptosis in nasal mucosal epithelial cells

Influenza A virus can induce nasal inflammation by stimulating the death of nasal mucosa epithelium, however, the mechanism is not clear. In this study, to study the causes and mechanisms of nasal mucosa epithelial cell death caused by Influenza A virus H1N1, we isolated and cultured human nasal epithelial progenitor cells (hNEPCs) and exposed them to H1N1 virus after leading differentiation. Then we performed high-resolution untargeted metabolomics and RNAseq analysis of human nasal epithelial cells (hNECs) infected with H1N1 virus. Surprisingly, H1N1 virus infection caused the differential expression of a large number of ferroptosis related genes and metabolites in hNECs. Furthermore, we have observed a significant reduction in Nrf2/KEAP1 expression, GCLC expression, and abnormal glutaminolysis. By constructing overexpression vector of GCLC and the shRNAs of GCLC and Keap1, we determined the role of NRF2-KEAP1-GCLC signaling pathway in H1N1 virus-induced ferroptosis. In addition, A glutaminase antagonist, JHU-083, also demonstrated that glutaminolysis can regulate the NRF2-KEAP1-GCLC signal pathway and ferroptosis. According to this study, H1N1 virus can induce the ferroptosis of hNECs via the NRF2-KEAP1-GCLC signal pathway and glutaminolysis, leading to nasal mucosal epithelial inflammation. This discovery is expected to provide an attractive therapeutic target for viral-induced nasal inflammation.

Nrf2 regulates the activation of THP-1 cells induced by chloral hydrate

Trichloroethylene (TCE) triggers a severe hypersensitivity syndrome in the occupational population dependent on dendritic cells (DCs). Chloral hydrate (CH), the major oxidative metabolite of TCE, has been proved to be the culprit causative substance of TCE-induced hypersensitivity by human patch tests. Because redox imbalance is essential for chemical sensitizers-induced maturation of DCs, we predicted that CH would activate DCs by the nuclear factor E2-related factor 2 (Nrf2)-mediated antioxidant response. This study selected THP-1 cells as the in vitro DC model, and we evaluated the cell activation markers, intracellular oxidative stress, and Nrf2 pathway related genes expression in response to CH in THP-1 cells. CH displayed significant stimulation of THP-1 cells activation, including CD54 and CD86 expression, IL-8 release, and cell migration, and damaged the redox balance by triggering ROS generation, GSH consumption, and antioxidase activities modulation. The levels of Nrf2 and its downstream genes (HO-1 and NQO1) in mRNA and protein expressions were upregulated by CH, and CH also promoted the nuclear translocation of Nrf2. Subsequently, we investigated the effects of antioxidant on Nrf2-mediated cell defense in CH treated cells. Pretreatment with curcumin dramatically reduced cell activation and oxidative stress triggered by CH in THP-1 cells. We also confirmed the specific role of Nrf2 in CH-induced cell activation using NRF2-knockout cells. Deficiency of Nrf2 inhibited cell activation and downregulated HO-1 and NQO1 expression in CH-challenged cells. These findings suggest that Nrf2-dependent redox homeostasis plays a pivotal role in CH-induced activation of THP-1 cells, thereby providing new knowledge of the allergen as well as the molecular mechanism involving in TCE-induce hypersensitivity syndrome.

Platelet Rich Plasma and Adipose-Derived Mesenchymal Stem Cells Mitigate Methotrexate-Induced Nephrotoxicity in Rat via Nrf2/Pparγ/HO-1 and NF-Κb/Keap1/Caspase-3 Signaling Pathways: Oxidative Stress and Apoptosis Interplay

BACKGROUND

the nephrotoxicity of methotrexate (MTX) is observed in high-dose therapy. Moreover, low-dose MTX therapy for rheumatic diseases is debatable and claimed to cause renal impairment. This study aimed at studying the effect of methotrexate in repeated low doses on rat kidneys and assessing the efficacy of adipose-derived mesenchymal stem cells (AD-MSCs) and platelet rich plasma (PRP) for attenuating this effect.

METHODS

Forty-two male Wistar rats were used, 10 rats were donors of AD-MSCs and PRP, 8 rats served as control, and the remaining rats were subjected to induction of nephrotoxicity by MTX intraperitoneal injection once weekly for successive 8 weeks and then assigned into 3 groups of 8 animals each: Group II: received MTX only. Group III: received MTX + PRP. Group IV: received MTX + AD-MSCs. After one month, rats were anaesthetized, serum-sampled, and renal tissue removed for biochemical, histological, and ultrastructural evaluation.

RESULTS

there was significant tubular degeneration, glomerulosclerosis, fibrosis, decreased renal index, along with increased levels of urea and creatinine in the MTX group compared to the control group. Immunohistochemical expression of caspase-3 and iNOS in the renal tissue was significantly increased in group II compared to groups III and IV. Biochemical results revealed higher tissue malondialdehyde (MDA) concentration in the MTX-injected group which decreased significantly in co-treatment with either AD-MSC or PRP + MTX. MSC promoted the activation of the Nrf2/PPARγ/HO-1 and NF-κB/Keap1/caspase-3 pathways, increased antioxidant enzyme activities, reduced lipid peroxidation levels, and alleviated oxidative damage and apoptosis. PRP showed therapeutic effects and molecular mechanisms similar to MSC. Furthermore, MSC and PRP treatment significantly reduced MTX-induced upregulation of the pro-inflammatory (NF-κB, interleukin-1ß, and TNF-α), oxidative stress (Nrf-2, hemoxygenase-1, glutathione, and malondialdehyde), and nitrosative stress (iNOS) markers in the kidney.

CONCLUSION

repeated administration of low-dose MTX resulted in massive renal tissue toxicity and deterioration of renal function in rats which proved to be attenuated by PRP and AD-MSCs through their anti-inflammatory, anti-apoptotic and anti-fibrotic properties.

Melatonin alleviates doxorubicin-induced cardiotoxicity via inhibiting oxidative stress, pyroptosis and apoptosis by activating Sirt1/Nrf2 pathway

Melatonin confers cardioprotective effects on multiple cardiovascular diseases, including doxorubicin-induced cardiomyopathy. The effectiveness of melatonin in mitigating myocardial injuries caused by Doxorubicin through enhancement of mitochondrial function is already established, however, the role of melatonin in regulating the Sirtuin-1 (Sirt1)/Nuclear factor E2-associated factor 2 (Nrf2) pathway in lessening the onset of Doxorubicin-induced cardiomyopathy is yet to be elucidated. To address this, H9C2 cardiomyocytes and C57BL/6 mice were employed to construct in vitro and in vivo models of Dox-induced myocardial impairments, respectively. Results showed that Dox markedly evoked oxidative stress, pyroptosis and apoptosis both in vitro and in vivo, which were significantly alleviated by melatonin administration. Mechanistically, melatonin attenuated Dox-induced downregulation of Sirt1 and Nrf2, and both inhibition of Sirt1 and Nrf2 significantly reversed the cardioprotective effects of melatonin. In conclusion, our studies suggest that the activation of the Sirt1/Nrf2 pathway is the underlying mechanism behind melatonin's ability to curtail oxidative stress, pyroptosis, and apoptosis in Dox-induced cardiomyopathy. These promising results demonstrated the potential application of melatonin as a treatment for doxorubicin-induced cardiac injury.

The preventive role of the red gingeng ginsenoside Rg3 in the treatment of lung tumorigenesis induced by benzo(a)pyrene

Red ginseng has been used in traditional medicine for centuries in Asia. In this study, we evaluated four types of red ginseng grown in different areas (Chinese red ginseng, Korean red ginseng A, Korean red ginseng B, and Korean red ginseng C) for their ability to inhibit lung tumor formation and growth induced by the carcinogen benzo(a)pyrene (B(a)P) in A/J mice and found that Korean red ginseng B was the most effective at lowering the tumor load among the four red ginseng varieties. Moreover, we analyzed the levels of various ginsenosides (Rg1, Re, Rc, Rb2, Rb3, Rb1, Rh1, Rd, Rg3, Rh2, F1, Rk1, and Rg5) in four kinds of red ginseng extract and found that Korean red ginseng B had the highest level of ginsenoside Rg3 (G-Rg3), which suggested that G-Rg3 may play an important role in its therapeutic efficacy. This work revealed that the bioavailability of G-Rg3 was relatively poor. However, when G-Rg3 was coadministered with verapamil, a P-glycoprotein inhibitor, the G-Rg3 efflux in Caco-2 cells was lowered, the small intestinal absorption rate of G-Rg3 in the rat models was increased, the concentration levels of G-Rg3 were elevated in the intestine and plasma, and its tumor-preventive abilities in the tumorigenesis rat model induced by B(a)P were also augmented. We also found that G-Rg3 reduced B(a)P-induced cytotoxicity and DNA adduct formation in human lung cells and rescued phase II enzyme expression and activity through Nrf2 pathways, which may be the potential mechanisms underlying the inhibitory effects of G-Rg3 on lung tumorigenesis. Our study showed a potentially vital role of G-Rg3 in targeting lung tumors in murine models. The oral bioavailability of this ginsenoside was augmented by targeting P-glycoprotein, which allowed the molecule to exert its anticancer effects.

Transcutaneous Electrical Acupoint Stimulation Pretreatment Alleviates Cerebral Ischemia-Reperfusion Injury in Rats by Modulating Microglia Polarization and Neuroinflammation Through Nrf2/HO-1 Signaling Pathway

Cerebral ischemia-reperfusion injury (CIRI) may lead to severe disability even death, but the strategies for prevention and treatment are still limited. Transcutaneous electrical acupoint stimulation (TEAS) has been reported to have a significant neuroprotection against CIRI, but the underlying mechanisms remain obscure. In this study, we established a focal cerebral ischemia-reperfusion model in male Sprague-Dawley rats. TEAS pretreatment was applied to Baihui (GV20), Sanyinjiao (SP6) and Zusanli (ST36) acupoints for 5 consecutive days before CIRI. After 24 h reperfusion, the brain damage was assessed using Zea-Longa score, brain water content (BWC) and infarct volume. Meanwhile, the number of activated microglia and the TNF-α were detected by immunofluorescence and ELISA respectively. Moreover, Western Blot and RT-qPCR were conducted to detect the proteins and mRNA expressions of Nrf2, HO-1, iNOS and Arg-1. We found that TEAS pretreatment significantly reduced Longa score, BWC, infarct volume and the number of activated microglia. Besides, TEAS pretreatment increased Nrf2 and HO-1 levels, while lowered the expression of TNF-α. Subsequently, we also discovered that the microglia M1 phenotype maker iNOS decreased and the M2 maker Arg-1 increased after TEAS pretreatment. However, these effects of TEAS pretreatment were markedly eliminated by brusatol. These findings clearly suggested that TEAS pretreatment exerted neuroprotection against CIRI, which might be related to modulating microglia polarization and neuroinflammation via Nrf2/HO-1 pathway.

Total saponins of Aralia elata (Miq.) Seem. alleviate myocardial ischemia-reperfusion injury by promoting NLRP3-inflammasome inactivation via PI3K/Akt signaling

Total saponins of Aralia elata (Miq.) Seem. (TSAE) have been shown to play a significant role in cardiovascular protection, anti-tumor, liver protection, anti-oxidant stress, and anti-inflammation. However, the specific mechanisms of TSAE in myocardial ischemia-reperfusion injury (MIRI) remain largely elusive. Hearts from male Wistar rats were used to establish the isolated heart MIRI model. Using a multichannel physiological recorder, the whole course heart rate (HR), left ventricular development pressure (LVDP), and maximum rise/decrease rate of left ventricular pressure (±dp/dt_max ) were recorded. 2,3,5-triphenyl-2H-tetrazolium chloride staining observed the infarct area, while hematoxylin & eosin staining detected pathological changes in myocardial tissue. Creatine kinase, lactate dehydrogenase, total superoxide dismutase, and malondialdehyde concentrations were determined by enzyme-linked immunosorbent assay. Immunohistochemistry, quantitative PCR, and western blot assay were used to assess the amounts of IL-18 and IL-1β, NLR family protein (NLRP3) inflammasome- and apoptosis-related proteins, respectively. Treatment with TSAE or MCC950 (NLRP3-specific inhibitor) significantly reduced the myocardial infarction area, alleviated pathological changes in myocardial tissues, enhanced LVDP and ±dp/dt_max levels, prevented myocardial oxidative damage, and inhibited NLRP3 inflammasome formation. In addition, TSAE enhanced Akt and GSK3β phosphorylation, and LY29004 co-reperfusion markedly diminished the protective role of TSAE reperfusion on cardiac function, oxidative damage, and inflammatory responses. Collectively, TSAE treatment exhibited a protective effect on I/R-triggered inflammatory responses, cell necrosis, and oxidative stress injury by stimulating PI3K/Akt signaling-mediated NLRP3 inflammasome inhibition.

Metabolic reprogramming by immune-responsive gene 1 up-regulation improves donor heart preservation and function

Preservation quality of donor hearts is a key determinant of transplant success. Preservation duration beyond 4 hours is associated with primary graft dysfunction (PGD). Given transport time constraints, geographical limitations exist for donor-recipient matching, leading to donor heart underutilization. Here, we showed that metabolic reprogramming through up-regulation of the enzyme immune response gene 1 (IRG1) and its product itaconate improved heart function after prolonged preservation. Irg1 transcript induction was achieved by adding the histone deacetylase (HDAC) inhibitor valproic acid (VPA) to a histidine-tryptophan-ketoglutarate solution used for donor heart preservation. VPA increased acetylated H3K27 occupancy at the IRG1 enhancer and IRG1 transcript expression in human donor hearts. IRG1 converts aconitate to itaconate, which has both anti-inflammatory and antioxidant properties. Accordingly, our studies showed that Irg1 transcript up-regulation by VPA treatment increased nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) in mice, which was accompanied by increased antioxidant protein expression [hemeoxygenase 1 (HO1) and superoxide dismutase 1 (SOD1)]. Deletion of Irg1 in mice (Irg1^-/-) negated the antioxidant and cardioprotective effects of VPA. Consistent with itaconate's ability to inhibit succinate dehydrogenase, VPA treatment of human hearts increased itaconate availability and reduced succinate accumulation during preservation. VPA similarly increased IRG1 expression in pig donor hearts and improved its function in an ex vivo cardiac perfusion system both at the clinical 4-hour preservation threshold and at 10 hours. These results suggest that augmentation of cardioprotective immune-metabolomic pathways may be a promising therapeutic strategy for improving donor heart function in transplantation.

Isorhapontigenin ameliorates high glucose-induced podocyte and vascular endothelial cell injuries via mitigating oxidative stress and autophagy through the AMPK/Nrf2 pathway

BACKGROUND

Diabetic nephropathy (DN) is a severe microvascular complication of diabetes mellitus and a primary reason for end-stage renal disease (ESRD). Isorhapontigenin (ISO), a natural derivative of stilbene, has significant anti-inflammatory and antioxidant effects. Nevertheless, its impact on DN remains elusive.

METHODS

Human vascular endothelial cells (HUVECs) and podocytes were damaged by high glucose (HG). Cell viability and apoptosis were testified by the cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. The mRNA profiles of antioxidant factors HO-1, NQO1, and Prx1 were monitored by real-time quantitative polymerase chain reaction (RT-qPCR). Western blotting (WB) was implemented to verify the expression of apoptosis-related proteins (Bax, Bad, and Bcl-XL), antioxidant factors (HO-1, NQO1, and Prx1), autophagy-related proteins (Beclin-1, ATG5, p62), podocalyxin (podocin, nephrin, and synaptopodin) and the AMPK/Nrf2 pathway. The levels of oxidative stress-related markers MDA, SOD and CAT were assessed with the corresponding kits. Compound C (CC), an inhibitor of AMPK, was deployed to probe the effects of modulating the AMPK/Nrf2 pathway on ISO in oxidative stress and autophagy in HUVECs and podocytes. Streptozotocin (STZ) was injected intraperitoneally into mice to establish an animal model of diabetes mellitus and to clarify the impact of ISO on the renal parameters such as serum creatinine, urea nitrogen and urinary protein in diabetic mice.

RESULTS

ISO notably facilitated cell proliferation, impeded apoptosis, elevated the expression of antioxidant-related factors, alleviated HG-induced oxidative stress and activated autophagy in HUVECs and podocytes. ISO activated the AMPK/Nrf2 pathway. Attenuating AMPK diminished the protective effect of ISO on HUVECs and podocytes, curbed cell proliferation, intensified apoptosis and oxidative stress, and dampened autophagy. In-vivo experiments also displayed that ISO reduced histopathological damage, lowered serum creatinine, urea nitrogen and urinary ACR levels, and eased kidney damage in DN mice.

CONCLUSION

ISO attenuates HG-induced oxidative stress and activates autophagy by motivating the AMPK/Nrf2 pathway, exerting a protective effect on HUVECs and podocytes and reducing renal injury in DN mice.

Emodin Regulates lncRNA XIST/miR-217 Axis to Protect Myocardial Ischemia-Reperfusion Injury

Purpose

This study is aimed at investigating the effect of emodin on myocardial ischemia-reperfusion injury (MIRI) and mechanism.

Methods

Eighty healthy adult male SD rats (weighing 230-250 g) were utilized to establish I/R model, which were randomly divided into five groups (16 rats in each group): sham operation group, myocardial ischemia-reperfusion injury group (I/R group), emodin group, emodin +NC group, and emodin +XIST group. The contents of CK, CK-MB, LDH, and HBDH in serum were determined by ELISA kit. LDH was detected by ELISA assay, SOD was detected by the xanthine oxidase method, and MDA was detected by the thiobarbituric acid method. The relative expression of XIST and miR-217 was evaluated by RT-qPCR. Western blot was applied to detect the protein expression. Flow cytometry was applied to detect cardiomyocyte apoptosis.

Results

Myocardial infarction area was obviously increased in I/R model rats, while emodin decreased the myocardial infarction in I/R model rats. In addition, cardiac enzymes (CK, CK-MB, LDH, and HBDH) and apoptosis were obviously increased in MIRI model rats, while emodin obviously decreased cardiac enzymes and apoptosis. The ROS and MDA levels were raised while the activities of SOD were declined in the I/R model group. The ROS and MDA levels were decreased while the activities of SOD were raised in the emodin group. The XIST expression was markedly raised in the I/R model group while decreased in the emodin group, and the overexpression of XIST reversed the protective effect of emodin on myocardial infarction, oxidative stress, and cardiomyocyte apoptosis. In addition, XIST directly regulated the expression of miR-217, and si-XIST inhibited H/R-induced oxidative damage of cardiomyocytes via inhibiting miR-217.

Conclusion

Emodin protected MIRI both in vitro and in vivo via inhibiting lncRNA XIST to upregulate miR-217.

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.

USP13 reduces septic mediated cardiomyocyte oxidative stress and inflammation by inducing Nrf2

BACKGROUND

Sepsis is a common cardiovascular complication that can cause heart damage. The regulatory role of ubiquitin-specific peptidase 13 (USP13) on erythroid 2-related factor 2 (Nrf2) has been reported, but its regulatory role in septic cardiomyopathy remains unclear.

METHODS

The Sprague Dawley (SD) rat model of septic myocardial injury was constructed by lipopolysaccharides (LPS). The serum lactate dehydrogenase (LDH) and creatine kinase (CK) levels were detected, the mRNA and protein expression levels of Nrf2 and USP13 in tissues were detected by real-time quantitative reverse transcription PCR (qRT-PCR) and western blot (WB), and the expression of USP13 at the treatment time of 3 h, 6 h, and 12 h was also detected. The cell viability and USP13, Nrf-2 and heme oxygenase-1 (HO-1) expression levels of H9C2-treated cells by LPS and the oxidative stress level and inflammatory response of H9C2 cells were detected by enzyme-linked immunosorbent assay (ELISA) and WB.

RESULTS

The results showed that USP13 was downregulated in septic myocardial injury tissues, and the Nrf2 level was increased in vitro after the cells were treated with LPS. Overexpression of USP13 further induced Nrf2 to reduce apoptosis, oxidative stress, and expression of inflammatory factors.

CONCLUSION

In conclusion, this study demonstrated that USP13 was downregulated in septic myocardial injury tissues, and USP13 overexpression increased Nrf2 levels and reduced apoptosis. Further studies showed that USP13 reduced LPS-induced oxidative stress and inflammation by inducing Nrf2.

Recent advances in nanomedicines for imaging and therapy of myocardial ischemia-reperfusion injury

Myocardial ischemia-reperfusion injury (IRI) is becoming a typical cardiovascular disease with increasing worldwide incidence. It is usually induced by the restoration of normal blood flow to the ischemic myocardium after a period of recanalization and directly leads to myocardial damage. Notably, the pathological mechanism of myocardial IRI is closely related to inflammation, oxidative stress, Ca²⁺ overload, and the opening of mitochondrial permeability transition pore channels. Therefore, monitoring of these changes and imaging lesions is a key to timely clinical diagnosis. Nanomedicines have shown great value in the diagnosis and treatment of myocardial IRI, with advantages including passive/active targeting, prolonged circulation, improved bioavailability, versatile carrier selection, and synergistic integration of different imaging and therapeutic agents in single particles with the same pharmaceutics. Because theranostic nanomedicines for myocardial IRI have advanced rapidly, we conduct an updated review on this topic. The special focus is on how to rationally design the nanomedicines to achieve optimal imaging and therapy. We hope this review would stimulate the interest of researchers with different backgrounds and expedite the development of nanomedicines for myocardial IRI.

Synergistic Effects of Ginsenoside Rb3 and Ferruginol in Ischemia-Induced Myocardial Infarction

Previous research shows that ginsenoside Rb3 (G-Rb3) exhibit significant protective effects on cardiomyocytes and is considered a promising treatment for myocardial infraction (MI). However, how to improve its oral bioavailability and reduce its dosage remains to be studied. Previous studies suggest that Ferruginol (FGL) may have synergistic effects with G-Rb3. However, the underlying mechanisms remain to be explored. In this study, left anterior descending branch (LAD) coronary artery ligation or oxygen-glucose deprivation-reperfusion (OGD/R) were used to establish MI models in vivo and in vitro. Subsequently, the pharmacological effects and mechanisms of G-Rb3-FGL were explored by in vitro studies. The results showed that the G-Rb3-FGL co-treatment improved heart functions better than the G-Rb3 treatment alone in MI mice models. Meanwhile, the G-Rb3-FGL co-treatment can upregulate fatty acids oxidation (FAO) and suppress oxidative stress in the heart tissues of MI mice. In vitro studies demonstrated that the synergistic effect of G-Rb3-FGL on FAO, oxidation and inflammation was abolished by RXRα inhibitor HX531 in the H9C2 cell model. In summary, we revealed that G-Rb3 and FGL have a synergistic effect against MI. They protected cardiomyocytes by promoting FAO, inhibiting oxidative stress, and suppressing inflammation through the RXRα-Nrf2 signaling pathway.

CircRNA02318 Exerts Therapeutic Effects on Myocardial Ischemia-Reperfusion Injury Rats by Regulating the Nox1/Akt Through Inhibiting Drebrin

Our research aims to explore the therapeutic effect of circRNA02318 on MIRI rats and the functional mechanism. The MIRI model was constructed in rats. CircRNA02318 overexpressing adenovirus was injected in situ during MIRI perfusion. H9C2 cells were treated with hypoxia for 6 h and reoxygenation for 3 h. Overexpression of circRNA02318 downregulated Drebrin, Nox1, cleaved caspase-3 and Bax in H/R H9C2 cells and MIRI rat heart tissues, promoted the expression of p-Akt/Akt and Bcl-2, and inhibited the apoptosis of H9C2 cells. The volume of myocardial infarction and the release of LDH and TnI in MIRI rats were suppressed by circRNA02318. The Nox1, cleaved caspase-3 and Bax levels were promoted, the level of p-Akt/Akt and Bcl-2 was repressed, and the apoptosis was facilitated by the Drebrin overexpression. Furthermore, the effect of Drebrin overexpression on H9C2 cells was abolished by circRNA02318. Collectively, circRNA02318 exerted therapeutic effects on MIRI rats by inhibiting Drebrin.

Wogonoside preserves against ischemia/reperfusion-induced myocardial injury by suppression of apoptosis, inflammation, and fibrosis via modulating Nrf2/HO-1 pathway

OBJECTIVE

Myocardial ischemia/reperfusion (I/R) injury occurs after restoring blood supply, which brings about extra damage to heart tissue. Thus, exploring protection measures and underlying mechanisms appear to be particularly important. In this study, we investigated the cardioprotection of wogonoside against I/R injury in mice and further uncovered its mechanism.

METHODS

Mice model of myocardial I/R injury was established by left anterior descending coronary artery (LAD). Before modeling, mice were administered the wogonoside (10, 20, and 40 mg/kg) for 7 d. To evaluate the effect of wogonoside through nuclear factor E2-associated factor 2/heme oxygenase-1 (Nrf2/HO-1) pathway, sh-Nrf2 was transfected into wogonoside-treated I/R mice. Subsequently, echocardiography detection, HE staining, western blotting, ELISA, TUNEL assay, and MASSON assay were utilized to evaluate the degree of myocardial injury.

RESULTS

In I/R group, mice had severe myocardial injury, however, pretreatment of wogonoside at doses of 20 and 40 mg/kg ameliorated the cardiac function, as evidenced by improving hemodynamic parameters. Besides, wogonoside could relieved the abnormality of cardiomyocytes structure, inflammatory reaction, apoptosis, and myocardial fibrosis. Importantly, wogonoside activated the Nrf2/HO-1 pathway, as demonstrated by increasing Nrf2 expression in nucleus and its downstream genes including HO-1 and NADPH quinone oxidoreductase-1 (NQO1). However, effects of wogonoside on cardioprotection were abolished by sh-Nrf2.

CONCLUSIONS

Wogonoside exerted the protective role against I/R-induced myocardial injury by suppression of apoptosis, inflammation, and fibrosis via activating Nrf2/HO-1 pathway.