MicroRNA-30c-5p protects against myocardial ischemia/reperfusion injury via regulation of Bach1/Nrf2

Renal denervation improves mitochondrial oxidative stress and cardiac hypertrophy through inactivating SP1/BACH1-PACS2 signaling

BACKGROUND

Renal denervation (RDN) has been proved to relieve cardiac hypertrophy; however, its detailed mechanisms remain obscure. This study investigated the detailed protective mechanisms of RDN against cardiac hypertrophy during hypertensive heart failure (HF).

METHODS

Male 5-month-old spontaneously hypertension (SHR) rats were used in a HF rat model, and male Wistar-Kyoto (WKY) rats of the same age were used as the baseline control. Myocardial hypertrophy and fibrosis were evaluated by hematoxylin-eosin (HE) staining and Masson staining. The expression of target molecule was analyzed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR), Western blot, immunohistochemical and immunofluorescence, respectively. Cardiomyocyte hypertrophy was induced by norepinephrine (NE) in H9c2 cells in vitro and evaluated by brain natriuretic peptide (BNP), atrial natriuretic peptide (ANP), β-myosin heavy chain (β-MHC), and α-myosin heavy chain (α-MHC) levels. Oxidative stress was determined by malondialdehyde (MDA) level, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) enzyme activities. Mitochondrial function was measured by mitochondrial membrane potential, adenosine triphosphate (ATP) production, mitochondrial DNA (mtDNA) number, and mitochondrial complex I-IV activities. Molecular mechanism was assessed by dual luciferase reporter and chromatin immunoprecipitation (ChIP) assays.

RESULTS

RDN decreased sympathetic nerve activity, attenuated myocardial hypertrophy and fibrosis, and improved cardiac function in the rat model of HF. In addition, RDN ameliorated mitochondrial oxidative stress in myocardial tissues as evidenced by reducing MDA and mitochondrial reactive oxygen species (ROS) levels, and enhancing SOD and GSH-Px activities. Moreover, phosphofurin acid cluster sorting protein 2 (PACS-2) and broad-complex, tramtrak and bric à brac (BTB) domain and cap'n'collar (CNC) homolog 1 (BACH1) were down-regulated by RDN. In NE-stimulated H9c2 cells, PACS-2 and BACH1 levels were markedly elevated, and knockdown of them could suppress NE-induced oxidative stress, cardiomyocyte hypertrophy, fibrosis, as well as mitochondrial dysfunction. Transforming growth factor beta1(TGFβ1)/SMADs signaling pathway was inactivated by RDN in the HF rats, which sequentially inhibited specificity protein 1 (SP1)-mediated transcription of PACS2 and BACH1.

CONCLUSION

Collectively, these data demonstrated that RDN improved cardiac hypertrophy and sympathetic nerve activity of HF rats via repressing BACH1 and PACS-2-mediated mitochondrial oxidative stress by inactivating TGF-β1/SMADs/SP1 pathway, which shed lights on the cardioprotective mechanism of RDN in HF.

Disruption of BACH1 Protects AC16 Cardiomyocytes Against Hypoxia/Reoxygenation-Evoked Injury by Diminishing CDKN3 Transcription

Reperfusion after myocardial infarction (MI) can lead to myocardial ischemia/reperfusion (I/R) damage. The transcription factor (TF) broad-complex, tramtrack, and bric-a-brac (BTB) and cap'n'collar (CNC) homology 1 (BACH1) is implicated in the injury. However, the downstream mechanisms of BACH1 in affecting myocardial hypoxia/reoxygenation (H/R) damage are still fully understood. AC16 cells were stimulated with H/R conditions to model cardiomyocytes under H/R. mRNA analysis was performed by quantitative real-time PCR. Protein levels were gauged by immunoblot analysis. The effect of BACH1/cyclin-dependent kinase inhibitor 3 (CDKN3) on H/R-evoked injury was assessed by measuring cell viability via Cell Counting Kit-8 (CCK-8), apoptosis (flow cytometry and caspase 3 activity), ferroptosis via Fe2+, glutathione (GSH), reactive oxygen species (ROS) and malondialdehyde (MDA) markers and inflammation cytokines interleukin-1beta (IL-1β) and tumor necrosis factor alpha (TNF-α). The BACH1/CDKN3 relationship was examined by chromatin immunoprecipitation (ChIP) experiment and luciferase assay. BACH1 was increased in MI serum and H/R-stimulated AC16 cardiomyocytes. Functionally, disruption of BACH1 mitigated H/R-evoked in vitro apoptosis, ferroptosis and inflammation of AC16 cardiomyocytes. Mechanistically, BACH1 activated CDKN3 transcription and enhanced CDKN3 protein expression in AC16 cardiomyocytes. Our rescue experiments validated that BACH1 disruption attenuated H/R-evoked AC16 cardiomyocyte apoptosis, ferroptosis and inflammation by downregulating CDKN3. Additionally, BACH1 disruption could activate the adenosine monophosphate-activated protein kinase (AMPK) signaling by downregulating CDKN3 in H/R-stimulated AC16 cardiomyocytes. Our study demonstrates that BACH1 activates CDKN3 transcription to induce H/R-evoked damage of AC16 cardiomyocytes partially via AMPK signaling.

Remifentanil represses oxidative stress to relieve hepatic ischemia/reperfusion injury via regulating BACH1/PRDX1 axis

BACKGROUND

Hepatic ischemia-reperfusion injury (HIRI) is a major cause of liver dysfunction after clinical liver surgery, which seriously affects the prognosis of patients. Remifentanil (RE) has been verified to attenuate HIRI. However, its therapeutic mechanism is still unclear. This study aimed to explore the protective mechanism of RE against HIRI.

METHODS

A mouse HIRI model and an in vitro model of hypoxia/reoxygenation (H/R)-stimulated AML12 hepatocytes were established. Liver histopathological changes were evaluated by hematoxylin and eosin (HE) staining. Oxidative stress damage was assessed by malondialdehyde (MDA), superoxide dismutase (SOD), and reactive oxygen species (ROS) levels. Liver function was determined by serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH). and adenosine triphosphate (ATP) levels. Cell counting kit-8 (CCK-8) assessed cell viability. Apoptosis was measured by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) and flow cytometry. The levels of inflammatory factors were detected by enzyme-linked immunosorbent assay (ELISA) kits. The differentially expressed genes were evaluated by mRNA microarray analysis. Western blotting and real-time quantitative polymerase chain reaction (RT-qPCR) were conducted to detect molecule expression. The binding of BTB and CNC homology 1 (BACH1) to peroxiredoxin 1 (PRDX1) was validated by chromatin immunoprecipitation (ChIP) and dual luciferase reporter assay.

RESULTS

RE treatment improved liver function, and repressed oxidative stress damage and apoptosis in HIRI mice. Nine differentially expressed genes in the liver tissues of HIRI mice were selected by microarray analysis, among which BACH1 was down-regulated and PRDX1 was up-regulated after RE treatment. In addition, BACH1 directly bound to the promoter region of PRDX1 to inhibit its transcription and expression, which led to oxidative stress injury. BACH1 overexpression or PRDX1 silencing could counteract the beneficial effects of RE against HIRI.

CONCLUSION

RE suppressed oxidative stress injury and inflammation via inactivation of the BACH1/PRDX1 axis, thereby ameliorating HIRI. Our findings enrich the understanding of the protective mechanisms of RE against HIRI, and provide novel evidence for its clinical application.

Multifaceted role of dynamin-related protein 1 in cardiovascular disease: From mitochondrial fission to therapeutic interventions

Mitochondria are central to cellular energy production and metabolic regulation, particularly in cardiomyocytes. These organelles constantly undergo cycles of fusion and fission, orchestrated by key proteins like Dynamin-related Protein 1 (Drp-1). This review focuses on the intricate roles of Drp-1 in regulating mitochondrial dynamics, its implications in cardiovascular health, and particularly in myocardial infarction. Drp-1 is not merely a mediator of mitochondrial fission; it also plays pivotal roles in autophagy, mitophagy, apoptosis, and necrosis in cardiac cells. This multifaceted functionality is often modulated through various post-translational alterations, and Drp-1's interaction with intracellular calcium (Ca2 + ) adds another layer of complexity. We also explore the pathological consequences of Drp-1 dysregulation, including increased reactive oxygen species (ROS) production and endothelial dysfunction. Furthermore, this review delves into the potential therapeutic interventions targeting Drp-1 to modulate mitochondrial dynamics and improve cardiovascular outcomes. We highlight recent findings on the interaction between Drp-1 and sirtuin-3 and suggest that understanding this interaction may open new avenues for therapeutically modulating endothelial cells, fibroblasts, and cardiomyocytes. As the cardiovascular system increasingly becomes the focal point of aging and chronic disease research, understanding the nuances of Drp-1's functionality can lead to innovative therapeutic approaches.

MiR-30c-5p-Targeted Regulation of GNAI2 Improves Neural Function Injury and Inflammation in Cerebral Ischemia-Reperfusion Injury

MiRNAs are related to neuronal proliferation and apoptosis following cerebral ischemia-reperfusion injury (CIRI). This study focused on miR-30c-5p in the disease. An oxygen-glucose deprivation/re-oxygenation (OGD/R) model was prepared in HT22 cells and transfected to overexpress miR-30c-5p and G Protein Subunit Alpha I2 (GNAI2) respectively or co-transfected to silence miR-30c-5p and GNAI2. Meanwhile, a middle cerebral artery occlusion (MCAO) model was constructed in mice, and miR-30c-5p and GNAI2 were silenced in vivo simultaneously. The mice were evaluated for neurological damage, apoptosis, and inflammation. HT22 cells were tested for cytotoxicity, proliferation, apoptosis, and inflammatory factors. The interaction between miR-30c-5p and GNAI2 was predicted, analyzed, and confirmed. MiR-30c-5p was found to be downregulated in both experimental models. miR-30c-5p reduced lactate dehydrogenase production, inflammatory response, inhibit apoptosis, and enhanced neuronal proliferation, while GNAI2 overexpression showed the opposite results. Downregulated miR-30c-5p worsened neurological function, apoptosis, and inflammation of MCAO mice while silencing GNAI2 attenuated the influence of downregulated miR-30c-5p. MiR-30c-5p can improve neuronal apoptosis and inflammatory response caused by CIRI and is neuroprotective by targeting GNAI2, providing a new target for treating CIRI.

Mechanisms by which silencing long-stranded noncoding RNA KCNQ1OT1 alleviates myocardial ischemia/reperfusion injury (MI/RI)-induced cardiac injury via miR-377-3p/HMOX1

BACKGROUND

The key complication of myocardial infarction therapy is myocardial ischemia/reperfusion injury (MI/RI), and there is no effective treatment. The present study elucidates the mechanism of action of lncRNA KCNQ1OT1 in alleviating MI/RI and provides new perspectives and therapeutic targets for cardiac injury-related diseases.

METHODS

An ischemia/reperfusion (I/R) injury model of human adult cardiac myocytes (HACMs) was constructed, and the expression of KCNQ1OT1 and miR-377-3p was determined by RT‒qPCR. The levels of related proteins were detected by western blot analysis. Cell proliferation was detected by a CCK-8 assay, and cell apoptosis and ROS content were determined by flow cytometry. SOD and MDA expression as well as Fe2+ changes were detected by related analysis kits. The target binding relationships between lncRNA KCNQ1OT1 and miR-377-3p as well as between miR-377-3p and heme oxygenase 1 (HMOX1) were verified by a dual-luciferase reporter gene assay.

RESULTS

Myocardial ischemia‒reperfusion caused oxidative stress in HACMs, resulting in elevated ROS levels, increased Fe2+ levels, decreased cell viability, and increased LDH release (a marker of myocardial injury), and apoptosis. KCNQ1OT1 and HMOX1 were upregulated in I/R-induced myocardial injury, but the level of miR-377-3p was decreased. A dual-luciferase reporter gene assay indicated that lncRNA KCNQ1OT1 targets miR-377-3p and that miR-377-3p targets HMOX1. Inhibition of HMOX1 alleviated miR-377-3p downregulation-induced myocardial injury. Furthermore, lncRNA KCNQ1OT1 promoted the level of HMOX1 by binding to miR-377-3p and aggravated myocardial injury.

CONCLUSION

LncRNA KCNQ1OT1 aggravates ischemia‒reperfusion-induced cardiac injury via miR-377-3P/HMOX1.

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.

Novel ceRNA network construction associated with programmed cell death in acute rejection of heart allograft in mice

Background

T cell-mediated acute rejection(AR) after heart transplantation(HT) ultimately results in graft failure and is a common indication for secondary transplantation. It's a serious threat to heart transplant recipients. This study aimed to explore the novel lncRNA-miRNA-mRNA networks that contributed to AR in a mouse heart transplantation model.

Methods

The donor heart from Babl/C mice was transplanted to C57BL/6 mice with heterotopic implantation to the abdominal cavity. The control group was syngeneic heart transplantation with the same kind of mice donor. The whole-transcriptome sequencing was performed to obtain differentially expressed mRNAs (DEmRNAs), miRNAs (DEmiRNAs) and lncRNAs (DElncRNAs) in mouse heart allograft. The biological functions of ceRNA networks was analyzed by GO and KEGG enrichment. Differentially expressed ceRNA involved in programmed cell death were further verified with qRT-PCR testing.

Results

Lots of DEmRNAs, DEmiRNAs and DElncRNAs were identified in acute rejection and control after heart transplantation, including up-regulated 4754 DEmRNAs, 1634 DElncRNAs, 182 DEmiRNAs, and down-regulated 4365 DEmRNAs, 1761 DElncRNAs, 132 DEmiRNAs. Based on the ceRNA theory, lncRNA-miRNA-mRNA regulatory networks were constructed in allograft acute rejection response. The functional enrichment analysis indicate that the down-regulated mRNAs are mainly involved in cardiac muscle cell contraction, potassium channel activity, etc. and the up-regulated mRNAs are mainly involved in T cell differentiation and mononuclear cell migration, etc. The KEGG pathway enrichment analysis showed that the down-regulated DEmRNAs were mainly enriched in adrenergic signaling, axon guidance, calcium signaling pathway, etc. The up-regulated DEmRNAs were enriched in the adhesion function, chemokine signaling pathway, apoptosis, etc. Four lncRNA-mediated ceRNA regulatory pathways, Pvt1/miR-30c-5p/Pdgfc, 1700071M16Rik/miR-145a-3p/Pdgfc, 1700071M16Rik/miR-145a-3p/Tox, 1700071M16Rik/miR-145a-3p/Themis2, were finally validated. In addition, increased expression of PVT1, 1700071M16Rik, Tox and Themis2 may be considered as potential diagnostic gene biomarkers in AR.

Conclusion

We speculated that Pvt1/miR-30c-5p/Pdgfc, 1700071M16Rik/miR-145a-3p/Pdgfc, 1700071M16Rik/miR-145a-3p/Tox and 1700071M16Rik/miR-145a-3p/Themis2 interaction pairs may serve as potential biomarkers in AR after HT.

Extracellular Vesicle MicroRNAs in Heart Failure: Pathophysiological Mediators and Therapeutic Targets

Extracellular vesicles (EVs) are emerging mediators of intracellular and inter-organ communications in cardiovascular diseases (CVDs), especially in the pathogenesis of heart failure through the transference of EV-containing bioactive substances. microRNAs (miRNAs) are contained in EV cargo and are involved in the progression of heart failure. Over the past several years, a growing body of evidence has suggested that the biogenesis of miRNAs and EVs is tightly regulated, and the sorting of miRNAs into EVs is highly selective and tightly controlled. Extracellular miRNAs, particularly circulating EV-miRNAs, have shown promising potential as prognostic and diagnostic biomarkers for heart failure and as therapeutic targets. In this review, we summarize the latest progress concerning the role of EV-miRNAs in HF and their application in a therapeutic strategy development for heart failure.

Myocardial ischemia-reperfusion injury; Molecular mechanisms and prevention

Cardiovascular diseases are one of the leading causes of mortality in developed countries. Among cardiovascular disorders, myocardial infarction remains a life-threatening problem predisposing to the development and progression of ischemic heart failure. Ischemia/reperfusion (I/R) injury is a critical cause of myocardial injury. In recent decades, many efforts have been made to find the molecular and cellular mechanisms underlying the development of myocardial I/R injury and post-ischemic remodeling. Some of these mechanisms are mitochondrial dysfunction, metabolic alterations, inflammation, high production of ROS, and autophagy deregulation. Despite continuous efforts, myocardial I/R injury remains a major challenge in medical treatments of thrombolytic therapy, heart disease, primary percutaneous coronary intervention, and coronary arterial bypass grafting. The development of effective therapeutic strategies to reduce or prevent myocardial I/R injury is of great clinical significance.

miR‑30c reduces myocardial ischemia/reperfusion injury by targeting SOX9 and suppressing pyroptosis

MicroRNAs (miRNAs or miRs) are commonly involved in regulating myocardial ischemia/reperfusion (I/R) injury by binding and silencing their target genes. However, whether miRNAs regulate myocardial I/R-induced pyroptosis remains unclear. The present study established an in vivo rat model of myocardial I/R injury and in vitro hypoxia/reoxygenation (H/R) injury model in rat primary cardiomyocytes to investigate the function and the underlying mechanisms of miRNAs on I/R injury-induced pyroptosis. RNA sequencing was utilized to select the candidate miRNAs between normal and I/R group. Reverse transcription-quantitative PCR and western blotting were performed to detect candidate miRNAs (miR-30c-5p, also known as miR-30c) and SRY-related high mobility group-box gene 9 (SOX9) expression, as well as expression of pyroptosis-associated proteins (NF-κB, ASC, caspase-1, NLRP3) in the myocardial I/R model. ELISA was used to measure pyroptosis-associated inflammatory markers IL-18 and IL-1β. Moreover, the link between miR-30c and SOX9 was predicted using bioinformatics and luciferase reporter assay. In myocardial I/R injured rats, miR-30c was downregulated, while the expression of SOX9 was upregulated. Overexpression of miR-30c inhibited pyroptosis both in vivo and in vitro. Furthermore, miR-30c negatively regulated SOX9 expression by binding its 3'untranslated region. In conclusion, the miR-30c/SOX9 axis decreased myocardial I/R injury by suppressing pyroptosis, which may be a potential therapeutic target.

Oxidative Stress and Epigenetics: miRNA Involvement in Rare Autoimmune Diseases

Autoimmune diseases (ADs) such as Sjögren’s syndrome, Kawasaki disease, and systemic sclerosis are characterized by chronic inflammation, oxidative stress, and autoantibodies, which cause joint tissue damage, vascular injury, fibrosis, and debilitation. Epigenetics participate in immune cell proliferation and differentiation, which regulates the development and function of the immune system, and ultimately interacts with other tissues. Indeed, overlapping of certain clinical features between ADs indicate that numerous immunologic-related mechanisms may directly participate in the onset and progression of these diseases. Despite the increasing number of studies that have attempted to elucidate the relationship between miRNAs and oxidative stress, autoimmune disorders and oxidative stress, and inflammation and miRNAs, an overall picture of the complex regulation of these three actors in the pathogenesis of ADs has yet to be formed. This review aims to shed light from a critical perspective on the key AD-related mechanisms by explaining the intricate regulatory ROS/miRNA/inflammation axis and the phenotypic features of these rare autoimmune diseases. The inflamma-miRs miR-155 and miR-146, and the redox-sensitive miR miR-223 have relevant roles in the inflammatory response and antioxidant system regulation of these diseases. ADs are characterized by clinical heterogeneity, which impedes early diagnosis and effective personalized treatment. Redox-sensitive miRNAs and inflamma-miRs can help improve personalized medicine in these complex and heterogeneous diseases.

The Role of ncRNAs in Cardiac Infarction and Regeneration

Myocardial infarction is the most prevalent cardiovascular disease worldwide, and it is defined as cardiomyocyte cell death due to a lack of oxygen supply. Such a temporary absence of oxygen supply, or ischemia, leads to extensive cardiomyocyte cell death in the affected myocardium. Notably, reactive oxygen species are generated during the reperfusion process, driving a novel wave of cell death. Consequently, the inflammatory process starts, followed by fibrotic scar formation. Limiting inflammation and resolving the fibrotic scar are essential biological processes with respect to providing a favorable environment for cardiac regeneration that is only achieved in a limited number of species. Distinct inductive signals and transcriptional regulatory factors are key components that modulate cardiac injury and regeneration. Over the last decade, the impact of non-coding RNAs has begun to be addressed in many cellular and pathological processes including myocardial infarction and regeneration. Herein, we provide a state-of-the-art review of the current functional role of diverse non-coding RNAs, particularly microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), in different biological processes involved in cardiac injury as well as in distinct experimental models of cardiac regeneration.

Emerging Role of MicroRNA-30c in Neurological Disorders

MicroRNAs (miRNAs or miRs) are a class of small non-coding RNAs that negatively regulate the expression of target genes by interacting with 3' untranslated regions of target mRNAs to induce mRNA degradation and translational repression. The miR-30 family members are involved in the development of many tissues and organs and participate in the pathogenesis of human diseases. As a key member of the miR-30 family, miR-30c has been implicated in neurological disorders such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and stroke. Mechanistically, miR-30c may act as a multi-functional regulator of different pathogenic processes such as autophagy, apoptosis, endoplasmic reticulum stress, inflammation, oxidative stress, thrombosis, and neurovascular function, thereby contributing to different disease states. Here, we review and discuss the biogenesis, gene regulation, and the role and mechanisms of action of miR-30c in several neurological disorders and therapeutic potential in clinics.

Protections of transcription factor BACH2 and natural product myricetin against pathological cardiac hypertrophy and dysfunction

Pathological hypertrophic myocardium under consistent adverse stimuli eventually can cause heart failure. This study aims to explore the role of BACH2, a member of the basic region leucine zipper transcription factor family, in cardiac hypertrophy and failure. Transverse aortic constriction surgery was operated to induce cardiac hypertrophy and failure in mice. BACH2 was overexpressed in mice through tail vein injection of AAV9-Bach2. Mice with systemic or cardiac-specific knockdown of Bach2 were adopted. Neonatal rat ventricular myocytes (NRVMs) were isolated and infected with lentivirus to overexpress Bach2 or transfected with siRNA to knock down Bach2. Our data showed that overexpression of BACH2 ameliorated TAC-induced cardiac hypertrophy and failure in mice and decreased isoproterenol (ISO)-triggered myocyte hypertrophy in NRVMs. Systemic or cardiac-specific knockdown of Bach2 worsened the cardiac hypertrophy and failure phenotype in mice. Further assays showed that BACH2 bound to the promotor region of Akap6 at the -600 to -587 site and repressed its expression, which functioned as a crucial scaffold for cardiac hypertrophy and failure signaling pathways. Small molecular natural product library screening suggested that myricetin could up-regulate expression of Bach2 and simultaneously suppress the transcriptional levels of hypertrophic marker genes Bnp and Myh7. Further studies showed that myricetin exerted a BACH2-dependent protective effect against cardiac hypertrophy in vivo and in vitro. Taken together, our findings demonstrated that BACH2 plays a crucial role in the regulation of cardiac hypertrophy and failure and can be a potential therapeutic target in the future.

Targeting Nrf2 in ischemia-reperfusion alleviation: From signaling networks to therapeutic targeting

The nuclear factor erythroid 2-related factor 2 (Nrf2) is a master regulator of redox balance and it responds to various cell stresses that oxidative stress is the most well-known one. The Nrf2 should undergo nuclear translocation to exert its protective impacts and decrease ROS production. On the other hand, ischemic/reperfusion (I/R) injury is a pathological event resulting from low blood flow to an organ and followed by reperfusion. The I/R induces cell injury and organ dysfunction. The present review focuses on Nrf2 function in alleviation of I/R injury. Stimulating of Nrf2 signaling ameliorates I/R injury in various organs including lung, liver, brain, testis and heart. The Nrf2 enhances activity of antioxidant enzymes to reduce ROS production and prevent oxidative stress-mediated cell death. Besides, Nrf2 reduces inflammation via decreasing levels of pro-inflammatory factors including IL-6, IL-1β and TNF-α. Nrf2 signaling is beneficial in preventing apoptosis and increasing cell viability. Nrf2 induces autophagy to prevent apoptosis during I/R injury. Furthermore, it can interact with other molecular pathways including PI3K/Akt, NF-κB, miRNAs, lncRNAs and GSK-3β among others, to ameliorate I/R injury. The therapeutic agents, most of them are phytochemicals such as resveratrol, berberine and curcumin, induce Nrf2 signaling in I/R injury alleviation.

Hypoxic/Ischemic Inflammation, MicroRNAs and δ-Opioid Receptors: Hypoxia/Ischemia-Sensitive Versus-Insensitive Organs

Hypoxia and ischemia cause inflammatory injury and critically participate in the pathogenesis of various diseases in various organs. However, the protective strategies against hypoxic and ischemic insults are very limited in clinical settings up to date. It is of utmost importance to improve our understanding of hypoxic/ischemic (H/I) inflammation and find novel therapies for better prevention/treatment of H/I injury. Recent studies provide strong evidence that the expression of microRNAs (miRNAs), which regulate gene expression and affect H/I inflammation through post-transcriptional mechanisms, are differentially altered in response to H/I stress, while δ-opioid receptors (DOR) play a protective role against H/I insults in different organs, including both H/I-sensitive organs (e.g., brain, kidney, and heart) and H/I-insensitive organs (e.g., liver and muscle). Indeed, many studies have demonstrated the crucial role of the DOR-mediated cyto-protection against H/I injury by several molecular pathways, including NLRP3 inflammasome modulated by miRNAs. In this review, we summarize our recent studies along with those of others worldwide, and compare the effects of DOR on H/I expression of miRNAs in H/I-sensitive and -insensitive organs. The alternation in miRNA expression profiles upon DOR activation and the potential impact on inflammatory injury in different organs under normoxic and hypoxic conditions are discussed at molecular and cellular levels. More in-depth investigations into this field may provide novel clues for new protective strategies against H/I inflammation in different types of organs.

Neuregulin (NRG-1β) Is Pro-Myogenic and Anti-Cachectic in Respiratory Muscles of Post-Myocardial Infarcted Swine

Neuregulin-1β (NRG-1β) is a growth and differentiation factor with pleiotropic systemic effects. Because NRG-1β has therapeutic potential for heart failure and has known growth effects in skeletal muscle, we hypothesized that it might affect heart failure-associated cachexia, a severe co-morbidity characterized by a loss of muscle mass. We therefore assessed NRG-1β's effect on intercostal skeletal muscle gene expression in a swine model of heart failure using recombinant glial growth factor 2 (USAN-cimaglermin alfa), a version of NRG-1β that has been tested in humans with systolic heart failure. Animals received one of two intravenous doses (0.67 or 2 mg/kg) of NRG-1β bi-weekly for 4 weeks, beginning one week after infarct. Based on paired-end RNA sequencing, NRG-1β treatment altered the intercostal muscle gene expression of 581 transcripts, including genes required for myofiber growth, maintenance and survival, such as MYH3, MYHC, MYL6B, KY and HES1. Importantly, NRG-1β altered the directionality of at least 85 genes associated with cachexia, including myostatin, which negatively regulates myoblast differentiation by down-regulating MyoD expression. Consistent with this, MyoD was increased in NRG-1β-treated animals. In vitro experiments with myoblast cell lines confirmed that NRG-1β induces ERBB-dependent differentiation. These findings suggest a NRG-1β-mediated anti-atrophic, anti-cachexia effect that may provide additional benefits to this potential therapy in heart failure.

Role and Potential Mechanism of Heme Oxygenase-1 in Intestinal Ischemia-Reperfusion Injury

Intestinal ischemia-reperfusion (IR) injury is a complex, multifactorial, and pathophysiological condition with high morbidity and mortality, leading to serious difficulties in treatment, especially in humans. Heme oxygenase (HO) is the rate-limiting enzyme involved in heme catabolism. HO-1 (an inducible form) confers cytoprotection by inhibiting inflammation and oxidation. Furthermore, nuclear factor-erythroid 2-related factor 2 (Nrf2) positively regulates HO-1 transcription, whereas BTB and CNC homolog 1 (Bach1) competes with Nrf2 and represses its transcription. We investigated the role and potential mechanism of action of HO-1 in intestinal IR injury. Intestinal ischemia was induced for 45 min followed by 4 h of reperfusion in wild-type, Bach1-deficient, and Nrf2-deficient mice, and a carbon monoxide (CO)-releasing molecule (CORM)-3 was administered. An increase in inflammatory marker levels, nuclear factor-κB (NF-κB) activation, and morphological impairments were observed in the IR-induced intestines of wild-type mice. These inflammatory changes were significantly attenuated in Bach1-deficient mice or those treated with CORM-3, and significantly exacerbated in Nrf2-deficient mice. Treatment with an HO-1 inhibitor reversed this attenuation in IR-induced Bach1-deficient mice. Bach1 deficiency and treatment with CORM-3 resulted in the downregulation of NF-κB activation and suppression of adhesion molecules. Together, Bach1, Nrf2, and CO are valuable therapeutic targets for intestinal IR injury.

The crosstalk between reactive oxygen species and noncoding RNAs: from cancer code to drug role

Oxidative stress (OS), characterized by the excessive accumulation of reactive oxygen species (ROS), is an emerging hallmark of cancer. Tumorigenesis and development driven by ROS require an aberrant redox homeostasis, that activates onco-signaling and avoids ROS-induced programmed death by orchestrating antioxidant systems. These processes are revealed to closely associate with noncoding RNAs (ncRNAs). On the basis of the available evidence, ncRNAs have been widely identified as multifarious modulators with the involvement of several key redox sensing pathways, such as NF-κB and Nrf2 signaling, therefore potentially becoming effective targets for cancer therapy. Furthermore, the vast majority of ncRNAs with property of easy detected in fluid samples (e.g., blood and urine) facilitate clinicians to monitor redox homeostasis, indicating a novel method for cancer diagnosis. Herein, focusing on carcinoma initiation, metastasis and chemoradiotherapy resistance, we aimed to discuss the ncRNAs-ROS network involved in cancer progression, and the potential clinical application as biomarkers and therapeutic targets.

Sevoflurane protects against cerebral ischemia/reperfusion injury via microrna-30c-5p modulating homeodomain-interacting protein kinase 1

Sevoflurane (SEV) has been reported to be an effective neuroprotective agent for cerebral ischemia/reperfusion injury (CIRI). However, the precise molecular mechanisms of Sev preconditioning in CIRI remain largely unknown. Therefore, CIRI model was established via middle cerebral artery occlusion method. SEV was applied before modeling. after successful modeling, lentivirus was injected into the lateral ventricle of the brain. Neurological impairment score was performed in each group, and histopathologic condition, infarct volume, apoptosis, inflammation, oxidative stress, microRNA (miR)-30 c-5p and homeodomain-interacting protein kinase 1 (HIPK1) were detected. Mouse hippocampal neuronal cell line HT22 cells were pretreated with SEV, and the in vitro model was stimulated via oxygen-glucose deprivation and reoxygenation. The corresponding plasmids were transfected, and the cell growth was detected, including inflammation and oxidative stress, etc. The targeting of miR-30 c-5p with HIPK1 was examined. The results clarified that reduced miR-30 c-5p and elevated HIPK1 were manifested in CIRI. SEV could improve CIRI and modulate the miR-30 c-5p-HIPK1 axis in vitro and in vivo, and miR-30 c-5p could target HIPK1. Depressed miR-30 c-5p could eliminate the protection of SEV in vitro and in vivo. Repression of HIPK1 reversed the effect of reduced miR-30 c-5p on CIRI. Therefore, it is concluded that SEV is available to depress CIRI via targeting HIPK1 through upregulated miR-30 c-5p.

Inhibition of miR-218-5p reduces myocardial ischemia-reperfusion injury in a Sprague-Dawley rat model by reducing oxidative stress and inflammation through MEF2C/NF-κB pathway

Following myocardial ischemia, myocardial reperfusion injury causes oxidative stress (OS) and inflammation, leading to myocardial cell apoptosis and necrosis. Recently, emerging studies have shown that microRNAs (miRNAs) contribute to the pathophysiology associated with myocardial ischemia-reperfusion (I/R). In this study, we conducted both in-vitro and in-vivo experiments to explore the role of miR-218-5p in ischemia-reperfusion (I/R)- or oxygen and glucose deprivation/reperfusion (OGD/R)-mediated cardiomyocyte injury. A total 44 Sprague-Dawley (SD) rats were used, and randomly divided into four groups, control group (n = 11), miR-218-5p-in group (n = 11), I/R group (n = 11), I/R + miR-218-5p-in group (n = 11). Our data showed that miR-218-5p was overexpressed in H9C2 cardiomyocytes under OGD/R treatment. miR-218-5p inhibition reduced the lactate dehydrogenase (LDH) activity and the levels of reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD), as well as the expression of tumor necrosis factor alpha (TNF-α), interleukin (IL-1β), and IL-6. Oppositely, miR-218-5p overexpression aggravated OGD/R-mediated damage on H9C2 cells, whereas nuclear factor kappa B (NF-κB) pathway inhibition or myocyte enhancer factor 2C (MEF2C) upregulation reversed miR-218-5p mimics-mediated effects. Bioinformatics analysis predicted that miR-218-5p targeted and dampened its expression, which was testified by the dual-luciferase reporter assay and RNA pull-down assay. In vivo, inhibiting miR-218-5p declined LDH activities and ROS, MDA and SOD levels in rat myocardial tissues under I/R injury, alleviated myocardial fibrosis and inflammatory reactions, and reduced myocardial infarction area. Overall, inhibition of miR-218-5p choked oxidative stress and inflammation in myocardial I/R injury via targeting MEF2C/NF-κB axis, thus relieving the disease progression.

Argon inhibits reactive oxygen species oxidative stress via the miR-21-mediated PDCD4/PTEN pathway to prevent myocardial ischemia/reperfusion injury

The objective of this study was to explore the effect of argon preconditioning on myocardial ischemia reperfusion (MI/R) injury and its mechanism. Cardiomyocytes H2C9 were pre-treated with 50% argon, and a cell model of oxygen-glucose deprivation (OGD) was established. CCK-8 and cytotoxicity detection kits were used to detect cell viability and lactate dehydrogenase (LDH) release. The miR-21 expression was detected using quantitative real-time polymerase chain reaction. Western blot analysis was performed to detect the expression of programmed cell death protein 4 (PDCD4) and homologous phosphatase and tensin homolog (PTEN) proteins. The levels of inflammatory factors (IL-1β, IL-6, and IL-8) and oxidative stress factors (reactive oxygen species ROS], malondialdehyde [MDA], and superoxide dismutase [SOD]) were measured using an enzyme-linked immunosorbent assay. The effect of argon on cell apoptosis was detected using flow cytometry. Argon increased the proliferation of cardiomyocytes induced by OGD, decreased the release of LDH in cell culture medium, increased miR-21 expression in cells, decreased the expression of miR-21 target proteins PDCD4 and PTEN, decreased the levels of inflammatory factors (interleukin-1β [IL-1β], interleukin-6 [IL-6], and interleukin-8 [IL-8]) and oxidative stress factors (ROS and MDA), increased the SOD content, and decreased the cell apoptosis rate. Our results suggest that argon preconditioning inhibited the PDCD4/PTEN pathway via miR-21, thereby inhibiting ROS oxidative stress and preventing MI/R injury.