Regulation of Nrf2 signaling pathway in heart failure: Role of extracellular vesicles and non-coding RNAs

Research hotspots and emerging trends of mesenchymal stem cells in cardiovascular diseases: a bibliometric-based visual analysis

Background

Mesenchymal stem cells (MSCs) have important research value and broad application prospects in cardiovascular diseases (CVDs). However, few bibliometric analyses on MSCs in cardiovascular diseases are available. This study aims to provide a thorough review of the cooperation and influence of countries, institutions, authors, and journals in the field of MSCs in cardiovascular diseases, with the provision of discoveries in the latest progress, evolution paths, frontier research hotspots, and future research trends in the regarding field.

Methods

The articles related to MSCs in cardiovascular diseases were retrieved from the Web of Science. The bibliometric study was performed by CiteSpace and VOSviewer, and the knowledge map was generated based on data obtained from retrieved articles.

Results

In our study, a total of 4,852 publications launched before August 31, 2023 were accessed through the Web of Science Core Collection (WoSCC) database via our searching strategy. Significant fluctuations in global publications were observed in the field of MSCs in CVDs. China emerged as the nation with the largest number of publications, yet a shortage of high-quality articles was noted. The interplay among countries, institutions, journals and authors is visually represented in the enclosed figures. Importantly, current research trends and hotspots are elucidated. Cluster analysis on references has highlighted the considerable interest in exosomes, extracellular vesicles, and microvesicles. Besides, keywords analysis revealed a strong emphasis on myocardial infarction, therapy, and transplantation. Treatment methods-related keywords were prominent, while keywords associated with extracellular vesicles gathered significant attention from the long-term perspective.

Conclusion

MSCs in CVDs have become a topic of active research interest, showcasing its latent value and potential. By summarizing the latest progress, identifying the research hotspots, and discussing the future trends in the advancement of MSCs in CVDs, we aim to offer valuable insights for considering research prospects.

RNA binding proteins as mediators of pathological cardiac remodeling

RNA binding proteins (RBPs) play a central in the post-transcriptional regulation of gene expression, which can account for up to 50% of all variations in protein expression within a cell. Following their binding to target RNAs, RBPs most typically confer changes in gene expression through modulation of alternative spicing, RNA stabilization/degradation, or ribosome loading/translation rate. All of these post-transcriptional regulatory processes have been shown to play a functional role in pathological cardiac remodeling, and a growing body of evidence is beginning to identify the mechanistic contribution of individual RBPs and their cardiac RNA targets. This review highlights the mechanisms of RBP-dependent post-transcriptional gene regulation in cardiomyocytes and fibroblasts and our current understanding of how RNA binding proteins functionally contribute to pathological cardiac remodeling.

Research advances on molecular mechanism and natural product therapy of iron metabolism in heart failure

The progression of heart failure (HF) is complex and involves multiple regulatory pathways. Iron ions play a crucial supportive role as a cofactor for important proteins such as hemoglobin, myoglobin, oxidative respiratory chain, and DNA synthetase, in the myocardial energy metabolism process. In recent years, numerous studies have shown that HF is associated with iron dysmetabolism, and deficiencies in iron and overload of iron can both lead to the development of various myocarditis diseases, which ultimately progress to HF. Iron toxicity and iron metabolism may be key targets for the diagnosis, treatment, and prevention of HF. Some iron chelators (such as desferrioxamine), antioxidants (such as ascorbate), Fer-1, and molecules that regulate iron levels (such as lactoferrin) have been shown to be effective in treating HF and protecting the myocardium in multiple studies. Additionally, certain natural compounds can play a significant role by mediating the imbalance of iron-related signaling pathways and expression levels. Therefore, this review not only summarizes the basic processes of iron metabolism in the body and the mechanisms by which they play a role in HF, with the aim of providing new clues and considerations for the treatment of HF, but also summarizes recent studies on natural chemical components that involve ferroptosis and its role in HF pathology, as well as the mechanisms by which naturally occurring products regulate ferroptosis in HF, with the aim of providing reference information for the development of new ferroptosis inhibitors and lead compounds for the treatment of HF in the future.

Extracellular vesicles in heart failure

Physiologically, extracellular vesicles (EVs) have been implicated as crucial mediators of immune response, cell homeostasis, angiogenesis, cell differentiation and growth, and tissue repair. In heart failure (HF) they may act as regulators of cardiac remodeling, microvascular inflammation, micro environmental changes, tissue fibrosis, atherosclerosis, neovascularization of plaques, endothelial dysfunction, thrombosis, and reciprocal heart-remote organ interaction. The chapter summaries the nomenclature, isolation, detection of EVs, their biologic role and function physiologically as well as in the pathogenesis of HF. Current challenges to the utilization of EVs as diagnostic and predictive biomarkers in HF are also discussed.

Effect and mechanism of Qing Gan Zi Shen decoction on heart damage induced by obesity and hypertension

ETHNOPHARMACOLOGICAL RELEVANCE

Qing Gan Zi Shen Decoction (QGZS) is a traditional Chinese formula. It has been extensively used for decades in the treatment of hypertension combined with metabolic diseases, but its cardioprotective effects and underlying mechanisms are poorly understood.

AIM OF THE STUDY

To explore the cardioprotective effects and potential mechanisms of QGZS in an animal model of obese hypertension.

MATERIALS AND METHODS

In this study, spontaneously hypertensive rats (SHRs) were utilized as an animal model to examine the effects of a high-fat diet and two concentrations of QGZS. Echocardiography, hematoxylin eosin (H&E) staining, and wheat germ agglutinin (WGA) staining were employed to assess the cardiac structure and function of the SHRs throughout a 16-week therapy period. Furthermore, Western blotting (WB) and immunofluorescence (IF) were employed to identify the levels of Nrf2 expression in the mitochondria, cytoplasm, and nucleus of the myocardium. Additionally, transmission electron microscopy and enzyme-linked immunosorbent assay (ELISA) were utilized to measure mitochondrial morphology and pro-inflammatory cytokine levels, respectively. Furthermore, Western blotting (WB), immunohistochemistry (IHC), and immunofluorescence (IF) techniques were employed to quantify the levels of marker proteins associated with myocardial fibrosis, cardiac inflammation, oxidative stress, and mitochondrial dysfunction.

RESULTS

QGZS inhibited weight gain and depressed systolic and mean arterial pressures in high-fat-fed SHRs. Echocardiographic results demonstrated that QGZS prevented the increase in left ventricular mass, restricted the growth of left ventricular diameter, and improved ejection fraction (EF), fractional shortening (FS), and the ratio of early diastolic peak velocity of transmitral flow (E) to late diastolic peak velocity (A) in high-fat-fed SHRs. This suggested that QGZS prevented ventricular remodeling and protected cardiac systolic and diastolic functions. H&E and WGA staining showed that QGZS improved cardiomyocyte disorders and restricted cardiomyocyte hypertrophy. The underlying mechanisms, QGZS attenuated the oxidative stress state, including reducing the generation of reactive oxygen species (ROS) in the myocardium, revitalizing the antioxidant enzyme system, and protecting mitochondrial function. Moreover, QGZS alleviated the pro-inflammatory state in high-fat-fed SHRs. What's more, QGZS significantly increased the expression level of Nrf2 in nuclei and mitochondria in rat heart tissues, exerting a proximate Nrf2 agonist effect.

CONCLUSIONS

QGZS exerted cardioprotective effects, in part due to its increasing expression of Nrf2 protein in the heart, which promoted Nrf2 nuclear expression.

Proteomic and Phosphoproteomic Analysis of Right Ventricular Hypertrophy in the Pulmonary Hypertension Rat Model

Pulmonary arterial hypertension (PAH) is a progressive disease that affects both the lungs and heart. Right ventricle (RV) hypertrophy is a primary pathological feature of PAH; however, its underlying molecular mechanisms remain insufficiently studied. In this study, we employed tandem mass tag (TMT)-based quantitative proteomics for the integrative analysis of the proteome and phosphoproteome of the RV derived from monocrotaline-induced PAH model rats. Compared with control samples, 564 significantly upregulated proteins, 616 downregulated proteins, 622 downregulated phosphopeptides, and 683 upregulated phosphopeptides were identified (P < 0.05, abs (log2 (fold change)) > log2 1.2) in the MCT samples. The quantitative real-time polymerase chain reaction (qRT-PCR) validated the expression levels of top 20 significantly altered proteins, including Nppa (natriuretic peptides A), latent TGF-β binding protein 2 (Ltbp2), periostin, connective tissue growth factor 2 (Ccn2), Ncam1 (neural cell adhesion molecule), quinone reductase 2 (Nqo2), and tropomodulin 4 (Tmod4). Western blotting confirmed the upregulation of Ncam1 and downregulation of Nqo2 and Tmod4 in both MCT-induced and hypoxia-induced PH rat models. Pathway enrichment analyses indicated that the altered proteins are associated with pathways, such as vesicle-mediated transport, actin cytoskeleton organization, TCA cycle, and respiratory electron transport. These significantly changed phosphoproteins were enriched in pathways such as diabetic cardiomyopathy, hypertrophic cardiomyopathy, glycolysis/gluconeogenesis, and cardiac muscle contraction. In summary, this study provides an initial analysis of the RV proteome and phosphoproteome in the progression of PAH, highlighting several RV dysfunction-associated proteins and pathways.

The crosstalk between Nrf2 and NF-κB pathways in coronary artery disease: Can it be regulated by SIRT6?

Coronary artery disease (CAD) is the leading cause of death worldwide. Oxidative stress and inflammation are major mechanisms responsible for the progression of CAD. Nuclear transcription factor erythroid-2 related factor 2 (Nrf2) is a transcription factor that modulates the cellular redox status. Nrf2 upregulation increases the expression of antioxidant genes, decreases the expression of Nuclear factor-kappa B (NF-kB), and increases free radical metabolism. Activated NF-kB increases the production of inflammatory cytokines causing endothelial dysfunction. The two pathways of Nrf2 and NF-kB can regulate the expression of each other. Foremost, the Nrf2 pathway can decrease the level of active NF-κB by increasing the level of antioxidants and cytoprotective enzymes. Furthermore, the Nrf2 pathway prevents IκB-α degradation, an inhibitor of NF-kB, and thus inhibits NF-κB mediated transcription. Also, NF-kB transcription inhibits Nrf2 activation by reducing the antioxidant response element (ARE) transcription. Sirtuin 6 (SIRT6) is a member of the Sirtuins family that was found to protect against cardiovascular diseases. SIRT6 can suppress the production of Reactive oxygen species (ROS) through deacetylation of NRF2 which results in NRF2 activation. Furthermore, SIRT6 can inhibit the inflammatory process through the downregulation of NF-kB transcription. Therefore, targeting sirtuins could be a therapeutic strategy to treat CAD. This review describes the potential role of SIRT6 in regulating the crosstalk between NRF2 and NF-kB signaling pathways in CAD.

Non-coding RNA-mediated modulation of ferroptosis in cardiovascular diseases

Cardiovascular disease (CVD) is a major contributor to increasing morbidity and mortality worldwide and seriously threatens human health and life. Cardiomyocyte death is considered the pathological basis of various CVDs, including myocardial infarction, heart failure, and aortic dissection. Multiple mechanisms, such as ferroptosis, necrosis, and apoptosis, contribute to cardiomyocyte death. Among them, ferroptosis is an iron-dependent form of programmed cell death that plays a vital role in various physiological and pathological processes, from development and aging to immunity and CVD. The dysregulation of ferroptosis has been shown to be closely associated with CVD progression, yet its underlying mechanisms are still not fully understood. In recent years, a growing amount of evidence suggests that non-coding RNAs (ncRNAs), particularly microRNAs, long non-coding RNAs, and circular RNAs, are involved in the regulation of ferroptosis, thus affecting CVD progression. Some ncRNAs also exhibit potential value as biomarker and/or therapeutic target for patients with CVD. In this review, we systematically summarize recent findings on the underlying mechanisms of ncRNAs involved in ferroptosis regulation and their role in CVD progression. We also focus on their clinical applications as diagnostic and prognostic biomarkers as well as therapeutic targets in CVD treatment. DATA AVAILABILITY: No new data were created or analyzed in this study. Data sharing is not applicable to this article.

Duality of Nrf2 in iron-overload cardiomyopathy

Cardiomyopathy deeply affects quality of life and mortality of patients with b-thalassemia or with transfusion-dependent myelodysplastic syndromes. Recently, a link between Nrf2 activity and iron metabolism has been reported in liver ironoverload murine models. Here, we studied C57B6 mice as healthy control and nuclear erythroid factor-2 knockout (Nrf2-/-) male mice aged 4 and 12 months. Eleven-month-old wild-type and Nrf2-/- mice were fed with either standard diet or a diet containing 2.5% carbonyl-iron (iron overload [IO]) for 4 weeks. We show that Nrf2-/- mice develop an age-dependent cardiomyopathy, characterized by severe oxidation, degradation of SERCA2A and iron accumulation. This was associated with local hepcidin expression and increased serum non-transferrin-bound iron, which promotes maladaptive cardiac remodeling and interstitial fibrosis related to overactivation of the TGF-b pathway. When mice were exposed to IO diet, the absence of Nrf2 was paradoxically protective against further heart iron accumulation. Indeed, the combination of prolonged oxidation and the burst induced by IO diet resulted in activation of the unfolded protein response (UPR) system, which in turn promotes hepcidin expression independently from heart iron accumulation. In the heart of Hbbth3/+ mice, a model of b-thalassemia intermedia, despite the activation of Nrf2 pathway, we found severe protein oxidation, activation of UPR system and cardiac fibrosis independently from heart iron content. We describe the dual role of Nrf2 when aging is combined with IO and its novel interrelation with UPR system to ensure cell survival. We open a new perspective for early and intense treatment of cardiomyopathy in patients with b-thalassemia before the appearance of heart iron accumulation.

Extracellular vesicles: Critical bilateral communicators in periphery-brain crosstalk in central nervous system disorders

Growing evidence shows that there is a comorbid mechanism between the central nervous system (CNS) and the peripheral organs. The bilateral transmission of signal molecules in periphery-brain crosstalk plays an important role in the underlying mechanism, which result from complex networks of neurohumoral circuits. Secreted by almost all cells and considered innovative information transport systems, extracellular vesicles (EVs) encapsulate and deliver nucleic acids, proteins, lipids, and various other bioactive regulators. Moreover, EVs can cross the blood-brain barrier (BBB), they are also identified primarily as essential communicators between the periphery and the CNS. In addition to transporting molecules under physiological or pathological conditions, EVs also show novel potential in targeted drug delivery. In this review, we discuss the mechanisms implicated in the transport of EVs in crosstalk between the peripheral and the central immune systems as well as in crosstalk between the peripheral organs and the brain in CNS disorders, especially in neurodegenerative diseases, stroke, and trauma. This work will help in elucidating the contributions of EVs to brain health and disorders, and promote the development of new strategies for minimally invasive treatment.

Small Extracellular Vesicles Derived from Induced Pluripotent Stem Cells in the Treatment of Myocardial Injury

Induced pluripotent stem cell (iPSC) therapy brings great hope to the treatment of myocardial injuries, while extracellular vesicles may be one of the main mechanisms of its action. iPSC-derived small extracellular vesicles (iPSCs-sEVs) can carry genetic and proteinaceous substances and mediate the interaction between iPSCs and target cells. In recent years, more and more studies have focused on the therapeutic effect of iPSCs-sEVs in myocardial injury. IPSCs-sEVs may be a new cell-free-based treatment for myocardial injury, including myocardial infarction, myocardial ischemia-reperfusion injury, coronary heart disease, and heart failure. In the current research on myocardial injury, the extraction of sEVs from mesenchymal stem cells induced by iPSCs was widely used. Isolation methods of iPSCs-sEVs for the treatment of myocardial injury include ultracentrifugation, isodensity gradient centrifugation, and size exclusion chromatography. Tail vein injection and intraductal administration are the most widely used routes of iPSCs-sEV administration. The characteristics of sEVs derived from iPSCs which were induced from different species and organs, including fibroblasts and bone marrow, were further compared. In addition, the beneficial genes of iPSC can be regulated through CRISPR/Cas9 to change the composition of sEVs and improve the abundance and expression diversity of them. This review focused on the strategies and mechanisms of iPSCs-sEVs in the treatment of myocardial injury, which provides a reference for future research and the application of iPSCs-sEVs.

The Current Therapeutic Role of Chromatin Remodeling for the Prognosis and Treatment of Heart Failure

Cardiovascular diseases are a major cause of death globally, with no cure to date. Many interventions have been studied and suggested, of which epigenetics and chromatin remodeling have been the most promising. Over the last decade, major advancements have been made in the field of chromatin remodeling, particularly for the treatment of heart failure, because of innovations in bioinformatics and gene therapy. Specifically, understanding changes to the chromatin architecture have been shown to alter cardiac disease progression via variations in genomic sequencing, targeting cardiac genes, using RNA molecules, and utilizing chromatin remodeler complexes. By understanding these chromatin remodeling mechanisms in an injured heart, treatments for heart failure have been suggested through individualized pharmaceutical interventions as well as biomarkers for major disease states. By understanding the current roles of chromatin remodeling in heart failure, a potential therapeutic approach may be discovered in the future.

The Complex Genetic and Epigenetic Regulation of the Nrf2 Pathways: A Review

Nrf2 is a major transcription factor that significantly regulates-directly or indirectly-more than 2000 genes. While many of these genes are involved in maintaining redox balance, others are involved in maintaining balance among metabolic pathways that are seemingly unrelated to oxidative stress. In the past 25 years, the number of factors involved in the activation, nuclear translocation, and deactivation of Nrf2 has continued to expand. The purpose of this review is to provide an overview of the remarkable complexity of the tortuous sequence of stop-and-go signals that not only regulate expression or repression, but may also modify transcriptional intensity as well as the specificity of promoter recognition, allowing fluidity of its gene expression profile depending on the various structural modifications the transcription factor encounters on its journey to the DNA. At present, more than 45 control points have been identified, many of which represent sites of action of the so-called Nrf2 activators. The complexity of the pathway and the synergistic interplay among combinations of control points help to explain the potential advantages seen with phytochemical compositions that simultaneously target multiple control points, compared to the traditional pharmaceutical paradigm of "one-drug, one-target".

Daucosterol Alleviates Alcohol-Induced Hepatic Injury and Inflammation through P38/NF-κB/NLRP3 Inflammasome Pathway

Alcoholic liver disease (ALD) is caused by chronic excessive alcohol consumption, which leads to inflammation, oxidative stress, lipid accumulation, liver fibrosis/cirrhosis, and even liver cancer. However, there are currently no effective drugs for ALD. Herein, we report that a natural phytosterol Daucosterol (DAU) can effectively protect against liver injury caused by alcohol, which plays anti-inflammatory and antioxidative roles in many chronic inflammatory diseases. Our results demonstrate that DAU ameliorates liver inflammation induced by alcohol through p38/nuclear factor kappa B (NF-κB)/NOD-like receptor protein-3 (NLRP3) inflammasome pathway. Briefly, DAU decreases NF-κB nuclear translocation and inhibits NLRP3 activation by decreasing p38 phosphorylation. At the same time, DAU also protects against hepatic oxidative stress and lipid accumulation. In conclusion, our research provides a new clue about the protective effects of naturally active substances on ALD.

Oxidative Stress and Extracellular Matrix Remodeling Are Signature Pathways of Extracellular Vesicles Released upon Morphine Exposure on Human Brain Microvascular Endothelial Cells

Morphine, a commonly used antinociceptive drug in hospitals, is known to cross the blood-brain barrier (BBB) by first passing through brain endothelial cells. Despite its pain-relieving effect, morphine also has detrimental effects, such as the potential induction of redox imbalance in the brain. However, there is still insufficient evidence of these effects on the brain, particularly on the brain endothelial cells and the extracellular vesicles that they naturally release. Indeed, extracellular vesicles (EVs) are nanosized bioparticles produced by almost all cell types and are currently thought to reflect the physiological state of their parent cells. These vesicles have emerged as a promising source of biomarkers by indicating the functional or dysfunctional state of their parent cells and, thus, allowing a better understanding of the biological processes involved in an adverse state. However, there is very little information on the morphine effect on human brain microvascular endothelial cells (HBMECs), and even less on their released EVs. Therefore, the current study aimed at unraveling the detrimental mechanisms of morphine exposure (at 1, 10, 25, 50 and 100 µM) for 24 h on human brain microvascular endothelial cells as well as on their associated EVs. Isolation of EVs was carried out using an affinity-based method. Several orthogonal techniques (NTA, western blotting and proteomics analysis) were used to validate the EVs enrichment, quality and concentration. Data-independent mass spectrometry (DIA-MS)-based proteomics was applied in order to analyze the proteome modulations induced by morphine on HBMECs and EVs. We were able to quantify almost 5500 proteins in HBMECs and 1500 proteins in EVs, of which 256 and 148, respectively, were found to be differentially expressed in at least one condition. Pathway enrichment analysis revealed that the "cell adhesion and extracellular matrix remodeling" process and the "HIF1 pathway", a pathway related to oxidative stress responses, were significantly modulated upon morphine exposure in HBMECs and EVs. Altogether, the combination of proteomics and bioinformatics findings highlighted shared pathways between HBMECs exposed to morphine and their released EVs. These results put forward molecular signatures of morphine-induced toxicity in HBMECs that were also carried by EVs. Therefore, EVs could potentially be regarded as a useful tool to investigate brain endothelial cells dysfunction, and to a different extent, the BBB dysfunction in patient circulation using these "signature pathways".

Induction of Cardiac Pathology: Endogenous versus Exogenous Nrf2 Upregulation

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a master regulator of the endogenous antioxidant response to reactive oxygen species as well as a controller of Phase II detoxification in response to xenobiotics. This amenity to specific external manipulation exploits the binding affinity of Nrf2 for its constitutive repressor and degradation facilitator Kelch-like erythroid cell-derived protein with CNC homology-associated protein 1 (Keap1). Derived from both natural and synthesized origins, these compounds have been extensively tested without definitive beneficial results. Unfortunately, multiple terminated trials have shown a negative side to Nrf2 with regard to cardiac pathologies while animal-based studies have demonstrated cardiomyocyte hypertrophy and heart failure after chronic Nrf2 upregulation. Putatively based on autophagic control of Nrf2 activity-modulating upstream factors, new evidence of miRNA involvement has added complexity to this mechanism. What follows is an extensive survey of Nrf2-regulating exogenous compounds that may promote cardiomyopathy, clinical trial evidence, and a comparison to exercise-induced factors that also upregulate Nrf2 while preventing cardiac pathologies.

High Glucose-Induced Cardiomyocyte Damage Involves Interplay between Endothelin ET-1/ETA/ETB Receptor and mTOR Pathway

Patients with type two diabetes mellitus (T2DM) are at increased risk for cardiovascular diseases. Impairments of endothelin-1 (ET-1) signaling and mTOR pathway have been implicated in diabetic cardiomyopathies. However, the molecular interplay between the ET-1 and mTOR pathway under high glucose (HG) conditions in H9c2 cardiomyoblasts has not been investigated. We employed MTT assay, qPCR, western blotting, fluorescence assays, and confocal microscopy to assess the oxidative stress and mitochondrial damage under hyperglycemic conditions in H9c2 cells. Our results showed that HG-induced cellular stress leads to a significant decline in cell survival and an impairment in the activation of ETA-R/ETB-R and the mTOR main components, Raptor and Rictor. These changes induced by HG were accompanied by a reactive oxygen species (ROS) level increase and mitochondrial membrane potential (MMP) loss. In addition, the fragmentation of mitochondria and a decrease in mitochondrial size were observed. However, the inhibition of either ETA-R alone by ambrisentan or ETA-R/ETB-R by bosentan or the partial blockage of the mTOR function by silencing Raptor or Rictor counteracted those adverse effects on the cellular function. Altogether, our findings prove that ET-1 signaling under HG conditions leads to a significant mitochondrial dysfunction involving contributions from the mTOR pathway.

Role of Nrf2 and HO-1 in intervertebral disc degeneration

Intervertebral disc degeneration (IDD) is a common age-related disease with clinical manifestations of lumbar and leg pain and limited mobility. The pathogenesis of IDD is mainly mediated by the death of intervertebral disc (IVD) cells and the imbalance of extracellular matrix (ECM) synthesis and degradation. Oxidative stress and inflammatory reactions are the important factors causing this pathological change. Therefore, the regulation of reactive oxygen species and production of inflammatory factors may be an effective strategy to delay the progression of IDD. In recent years, nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream regulated protein heme oxygenase-1 (HO-1) have received special attention due to their antioxidant, anti-inflammatory and anti-apoptotic protective effects. Recent studies have elucidated the important role of these two proteins in the treatment of IDD disease. However, Nrf2 and HO-1 have not been systematically reported in IDD-related diseases. Therefore, this review describes the biological characteristics of Nrf2 and HO-1, the relationship between Nrf2- and HO-1-regulated oxidative stress and the inflammatory response and IDD, and the progress in research on some extracts targeting Nrf2 and HO-1 to improve IDD. Understanding the role and mechanism of Nrf2 and HO-1 in IDD may provide novel ideas for the clinical treatment and development of Nrf2- and HO-1-targeted drugs.

Extracellular Vesicles Regulate Sympatho-Excitation by Nrf2 in Heart Failure

BACKGROUND

Chronic heart failure (CHF) is associated with redox imbalance. Downregulation of Nrf2 (nuclear factor [erythroid-derived 2]-like 2) plays important roles in disrupting myocardial redox homeostasis and mediating sympathetic nerve activity in the setting of CHF. However, it is unclear if circulating extracellular vesicles (EVs) elicit sympathetic excitation in CHF by disrupting central redox homeostasis. We tested the hypothesis that cardiac-derived EVs circulate to the presympathetic rostral ventrolateral medulla and contribute to oxidative stress and sympathetic excitation via EV-enriched microRNA-mediated Nrf2 downregulation.

METHODS

Data were collected on rats with CHF post-myocardial infarction (MI) and on human subjects with ischemic CHF. EVs were isolated from tissue and plasma, and we determined the miRNAs cargo that related to targeting Nrf2 translation. We tracked the distribution of cardiac-derived EVs using in vitro labeled circulating EVs and cardiac-specific membrane GFP+ transgenic mice. Finally, we tested the impact of exogenously loading of antagomirs to specific Nrf2-related miRNAs on CHF-EV-induced pathophysiological phenotypes in normal rats (eg, sympathetic and cardiac function).

RESULTS

Nrf2 downregulation in CHF rats was associated with an upregulation of Nrf2-targeting miRNAs, which were abundant in cardiac-derived and circulating EVs from rats and humans. EVs isolated from the brain of CHF rats were also enriched with Nrf2-targeting miRNAs and cardiac-specific miRNAs. Cardiac-derived EVs were taken up by neurons in the rostral ventrolateral medulla. The administration of cardiac-derived and circulating EVs from CHF rats into the rostral ventrolateral medulla of normal rats evoked an increase in renal sympathetic nerve activity and plasma norepinephrine compared with Sham-operated rats, which were attenuated by exogenously preloading CHF-EVs with antagomirs to Nrf2-targeting miRNAs.

CONCLUSIONS

Cardiac microRNA-enriched EVs from animals with CHF can mediate crosstalk between the heart and the brain in the regulation of sympathetic outflow by targeting the Nrf2/antioxidant signaling pathway. This new endocrine signaling pathway regulating sympathetic outflow in CHF may be exploited for novel therapeutics.

Protective effect of fluoxetine against oxidative stress induced by renal ischemia-reperfusion injury via the regulation of miR-450b-5p/Nrf2 axis

The present study was performed to assess the protective effect of fluoxetine (FLX) on renal ischemia-reperfusion injury (IRI) via the regulation of miR-450b-5p/Nrf2 axis in male rats. In vivo, these male rats were randomly divided into different treatment groups. The rats were administered with FLX (20 mg/kg, intraperitoneally) once daily for 3 days before operation. The pathomorphological changes of renal tissues were assessed by histological examination and Masson staining. In vitro, HK-2 cells were used to detect the activity by CCK-8 assay in Hypoxia/Reoxygenation (H/R) group and Hypoxia/Reoxygenation+Fluoxetine (H/R+FLX) group. In addition, the oxidative stress biomarkers were evaluated. Subsequently, Nrf2, NF-κB, and Nrf2-dependent antioxidant enzymes, were detected by Western blot assay. In vivo, the pathological changes and serological renal function were significantly relieved in the rats with the pre-treatment of FLX, compared to IRI group. After FLX stimulation, the expression levels of oxidative stress indices significantly decreased, while tissue antioxidant indices significantly increased, compared to IRI group. The differently expressed miRNAs on renal IRI in male rats were screened out by miRNA microarray, especially showing that miR-450b-5p was selected as the target miRNA. Following miR-450b-5p agomir injection, the pathological changes and oxidative stress biomarkers significantly aggravated, whether in IRI group or IRI+FLX group. Bioinformatics analysis and double-luciferase reporter assay demonstrated that miR-450b-5p directly targeted Nrf2. The expression level of NF-κB significantly increased, while the expression levels of Nrf2 and Nrf2-dependent antioxidant enzymes significantly decreased after miR-450b-5p agomir injection. Furthermore, the expression levels of Nrf2 and it-dependent antioxidant enzymes were apparently increased in ischemic kidney after the transfection of miR-450b-5p mimic+recombination protein Nrf2, as well as the decreased expression levels of intracellular ROS and iNOS. In vitro, FLX significantly increased HK-2 cell viability, and relieved H/R HK-2 cell oxidative injury via down-regulating ROS and iNOS. In addition, H/R-induced oxidative damage was recovered with miR-450b-5p mimic and recombination protein Nrf2. Consequently, FLX played an important protective role in renal IRI-induced oxidative damage by promoting antioxidation via targeting miR-450b-5p/Nrf2 axis.

Peripheral chemoreflex modulation of renal hemodynamics and renal tissue PO2 in chronic heart failure with reduced ejection fraction

Aberrant carotid body chemoreceptor (CBC) function contributes to increased sympathetic nerve activity (SNA) and reduced renal blood flow (RBF) in chronic heart failure (CHF). Intermittent asphyxia (IA) mimicking sleep apnea is associated with additional increases in SNA and may worsen reductions in RBF and renal PO2 (RPO2) in CHF. The combined effects of decreased RBF and RPO2 may contribute to biochemical changes precipitating renal injury. This study sought to determine the role of CBC activity on glomerular filtration rate (GFR), RBF and RPO2 in CHF, and to assess the additive effects of IA. Furthermore, we sought to identify changes in gene expression that might contribute to renal injury. We hypothesized that GFR, RBF, and RPO2 would be reduced in CHF, that decreases in RBF and RPO2 would be worsened by IA, and that these changes would be ameliorated by CBC ablation (CBD). Finally, we hypothesized that CHF would be associated with pro-oxidative pro-fibrotic changes in renal gene expression that would be ameliorated by CBD. CHF was induced in adult male Sprague Dawley rats using coronary artery ligation (CAL). Carotid body denervation was performed by cryogenic ablation. GFR was assessed in conscious animals at the beginning and end of the experimental period. At 8-weeks post-CAL, cardiac function was assessed via echocardiography, and GFR, baseline and IA RBF and RPO2 were measured. Renal gene expression was measured using qRT-PCR. GFR was lower in CHF compared to sham (p < 0.05) but CBD had no salutary effect. RBF and RPO2 were decreased in CHF compared to sham (p < 0.05), and this effect was attenuated by CBD (p < 0.05). RBF and RPO2 were reduced to a greater extent in CHF vs. sham during exposure to IA (p < 0.05), and this effect was attenuated by CBD for RBF (p < 0.05). Downregulation of antioxidant defense and fibrosis-suppressing genes was observed in CHF vs. sham however CBD had no salutary effect. These results suggest that aberrant CBC function in CHF has a clear modulatory effect on RBF during normoxia and during IA simulating central sleep apnea.

Daidzein alleviates doxorubicin-induced heart failure via the SIRT3/FOXO3a signaling pathway

Heart failure (HF) is a clinical syndrome characterized by typical symptoms that usually occur at the end stage of various heart diseases and lead to death. Daidzein (DAI), an isoflavone found in soy foods, is widely used to treat menopausal syndrome, prostate cancer, breast cancer, heart disease, cardiovascular disease, and osteoporosis, and has anti-oxidant and anti-inflammatory properties. However, the effects of DAI in HF remain unknown. In this study, doxorubicin (DOX) was used to establish HF models of C57BL/6J mice and H9c2 cells with DAI treatment. Our results showed that DAI markedly improved the DOX-induced decline in cardiac function, and decreased the left ventricular ejection fraction, cardiac inflammation, oxidative stress, apoptosis, and fibrosis. Mechanistically, DAI affects cardiac energy metabolism by regulating SIRT3, and meets the ATP demand of the heart by improving glucose, lipid, and ketone body metabolism as well as restoring mitochondrial dysfunction in vivo and in vitro. Additionally, DAI can exert an antioxidant function and alleviate HF through the SIRT3/FOXO3a pathway. In conclusion, we demonstrate that DAI alleviates DOX-induced cardiotoxicity by regulating cardiac energy metabolism as well as reducing inflammation, oxidative stress, apoptosis and fibrosis, indicating its potential application for HF treatment.

Diagnostic and Therapeutic Roles of Extracellular Vesicles in Aging-Related Diseases

Aging shows a decline in overall physical function, and cellular senescence is the powerful catalyst leading to aging. Considering that aging will be accompanied with the emergence of various aging-related diseases, research on new antiaging drugs is still valuable. Extracellular vesicles (EVs), as tools for intercellular communication, are important components of the senescence-associated secretory phenotype (SASP), and they can play pathological roles in the process of cellular senescence. In addition, EVs are similar to their original cells in functions. Therefore, EVs derived from pathological tissues or body fluids may be closely related to the progression of diseases and become potential biomarkers, while those from healthy cells may have therapeutic effects. Moreover, EVs are satisfactory drug carriers. At present, numerous studies have supported the idea that engineered EVs could improve drug targeting ability and utilization efficiency. Here, we summarize the characteristics of EVs and cellular senescence and focus on the diagnostic and therapeutic potential of EVs in various aging-related diseases, including Alzheimer disease, osteoporosis, cardiovascular disease, diabetes mellitus and its complications, and skin aging.

Extracellular vesicles as bioactive nanotherapeutics: An emerging paradigm for regenerative medicine

In recent decades, extracellular vesicles (EVs), as bioactive cell-secreted nanoparticles which are involved in various physiological and pathological processes including cell proliferation, immune regulation, angiogenesis and tissue repair, have emerged as one of the most attractive nanotherapeutics for regenerative medicine. Herein we provide a systematic review of the latest progress of EVs for regenerative applications. Firstly, we will briefly introduce the biogenesis, function and isolation technology of EVs. Then, the underlying therapeutic mechanisms of the native unmodified EVs and engineering strategies of the modified EVs as regenerative entities will be discussed. Subsequently, the main focus will be placed on the tissue repair and regeneration applications of EVs on various organs including brain, heart, bone and cartilage, liver and kidney, as well as skin. More importantly, current clinical trials of EVs for regenerative medicine will also be briefly highlighted. Finally, the future challenges and insightful perspectives of the currently developed EV-based nanotherapeutics in biomedicine will be discussed. In short, the bioactive EV-based nanotherapeutics have opened new horizons for biologists, chemists, nanoscientists, pharmacists, as well as clinicians, making possible powerful tools and therapies for regenerative medicine.

Human Cardiac Progenitor Cell-Derived Extracellular Vesicles Exhibit Promising Potential for Supporting Cardiac Repair in Vitro

Although human Cardiac Progenitor Cells (hCPCs) are not retained by host myocardium they still improve cardiac function when injected into ischemic heart. Emerging evidence supports the hypothesis that hCPC beneficial effects are induced by paracrine action on resident cells. Extracellular vesicles (EVs) are an intriguing mechanism of cell communication based on the transport and transfer of peptides, lipids, and nucleic acids that have the potential to modulate signaling pathways, cell growth, migration, and proliferation of recipient cells. We hypothesize that EVs are involved in the paracrine effects elicited by hCPCs and held accountable for the response of the infarcted myocardium to hCPC-based cell therapy. To test this theory, we collected EVs released by hCPCs isolated from healthy myocardium and evaluated the effects they elicited when administered to resident hCPC and cardiac fibroblasts (CFs) isolated from patients with post-ischemic end-stage heart failure. Evidence emerging from our study indicated that hCPC-derived EVs impacted upon proliferation and survival of hCPCs residing in the ischemic heart and regulated the synthesis and deposition of extracellular-matrix by CFs. These findings suggest that beneficial effects exerted by hCPC injection are, at least to some extent, ascribable to the delivery of signals conveyed by EVs.

Extracellular Vesicles in Redox Signaling and Metabolic Regulation in Chronic Kidney Disease

Chronic kidney disease (CKD) is a world health problem increasing dramatically. The onset of CKD is driven by several mechanisms; among them, metabolic reprogramming and changes in redox signaling play critical roles in the advancement of inflammation and the subsequent fibrosis, common pathologies observed in all forms of CKD. Extracellular vesicles (EVs) are cell-derived membrane packages strongly associated with cell-cell communication since they transfer several biomolecules that serve as mediators in redox signaling and metabolic reprogramming in the recipient cells. Recent studies suggest that EVs, especially exosomes, the smallest subtype of EVs, play a fundamental role in spreading renal injury in CKD. Therefore, this review summarizes the current information about EVs and their cargos’ participation in metabolic reprogramming and mitochondrial impairment in CKD and their role in redox signaling changes. Finally, we analyze the effects of these EV-induced changes in the amplification of inflammatory and fibrotic processes in the progression of CKD. Furthermore, the data suggest that the identification of the signaling pathways involved in the release of EVs and their cargo under pathological renal conditions can allow the identification of new possible targets of injury spread, with the goal of preventing CKD progression.

A Novel Compound, Tanshinol Borneol Ester, Ameliorates Pressure Overload-Induced Cardiac Hypertrophy by Inhibiting Oxidative Stress via the mTOR/β-TrCP/NRF2 Pathway

Tanshinol borneol ester (DBZ) exerts anti-atherosclerotic and anti-inflammatory effects. However, its effects on cardiac hypertrophy are not well understood. In this work, we investigated the treatment effects and potential mechanisms of DBZ on the hypertrophic heart under oxidative stress and endoplasmic reticulum (ER) stress. A hypertrophic model was established in rats using transverse-aortic constriction (TAC) surgery and in neonatal rat cardiomyocytes (NRCMs) using angiotensin II (Ang II). Our results revealed that DBZ remarkably inhibited oxidative stress and ER stress, blocked autophagy flow, and decreased apoptosis in vivo and in vitro through nuclear NRF2 accumulation, and enhanced NRF2 stability via regulating the mTOR/β-TrcP/NRF2 signal pathway. Thus, DBZ may serve as a promising therapeutic for stress-induced cardiac hypertrophy.

miR-129-5p restores cardiac function in rats with chronic heart failure by targeting the E3 ubiquitin ligase Smurf1 and promoting PTEN expression

Chronic heart failure (CHF) is a prevalent health concern with complex pathogenesis. This current study set out to estimate the function of the miR-129-5p/Smurf1/PTEN axis on cardiac function injury in CHF. The model of CHF in rats was established. The cardiac function indexes, myocardial tissue damage, and oxidative stress-related factors in CHF rats were evaluated after the interference of Smurf1/miR-129-5p/PTEN. The targeting relationships between miR-129-5p and Smurf1 and between PTEN and Smurf1 were verified. It was found that that after modeling, cardiac functions were impaired, heart/left ventricular/lung weight and the myocardial structure was destroyed, and the degree of fibrosis of myocardial tissue was increased. After Smurf1 knockdown, the cardiac function, myocardial structure, and oxidative stress were improved, and the fibrosis in myocardial tissue was decreased. Smurf1 was a target of miR-129-5p. miR-129-5p could annul the protective effect of Smurf1 silencing on CHF rats. Smurf1 inhibited PTEN expression by promoting PTEN ubiquitination, while miR-129-5p enhanced PTEN expression by inhibiting Smurf1. Meanwhile, overexpression of PTEN annulled the cardiac dysfunction in CHF rats induced by Smurf1. In conclusion, miR-129-5p targeted Smurf1 and repressed the ubiquitination of PTEN, and promoted PTEN expression, thus improving the cardiac function of CHF rats.

Nrf2 and Heme Oxygenase-1 Involvement in Atherosclerosis Related Oxidative Stress

Atherosclerosis remains the underlying process responsible for cardiovascular diseases and the high mortality rates associated. This chronic inflammatory disease progresses with the formation of occlusive atherosclerotic plaques over the inner walls of vascular vessels, with oxidative stress being an important element of this pathology. Oxidation of low-density lipoproteins (ox-LDL) induces endothelial dysfunction, foam cell activation, and inflammatory response, resulting in the formation of fatty streaks in the atherosclerotic wall. With this in mind, different approaches aim to reduce oxidative damage as a strategy to tackle the progression of atherosclerosis. Special attention has been paid in recent years to the transcription factor Nrf2 and its downstream-regulated protein heme oxygenase-1 (HO-1), both known to provide protection against atherosclerotic injury. In the current review, we summarize the involvement of oxidative stress in atherosclerosis, focusing on the role that these antioxidant molecules exert, as well as the potential therapeutic strategies applied to enhance their antioxidant and antiatherogenic properties.

Recent advances in Extracellular Vesicles and their involvements in vasculitis

Systemic vasculitis is a heterogeneous group of multisystem autoimmune disorders characterized by inflammation of blood vessels. Although many progresses in diagnosis and immunotherapies have been achieved over the past decades, there are still many unanswered questions about vasculitis from pathological understanding to more advanced therapies. Extracellular vesicles (EVs) are double-layer phospholipid membrane vesicles harboring various cargoes. EVs can be classified into exosomes, microvesicles (MVs), and apoptotic bodies depending on their size and origin of cellular compartment. EVs can be released by almost all cell types and may be involved in physical and pathological processes including inflammation and autoimmune responses. In systemic vasculitis, EVs may have pathogenic involvement in inflammation, autoimmune responses, thrombosis, endothelium injury, angiogenesis and intimal hyperplasia. EV-associated redox reaction may also be involved in vasculitis pathogenesis by inducing inflammation, endothelial injury and thrombosis. Additionally, EVs may serve as specific biomarkers for diagnosis or monitoring of disease activity and therapeutic efficacy, i.e. AAV-associated renal involvement. In this review, we have discussed the recent advances of EVs, especially their roles in pathogenesis and clinical involvements in vasculitis.

Extracellular Vesicles under Oxidative Stress Conditions: Biological Properties and Physiological Roles

Under physio-pathological conditions, cells release membrane-surrounded structures named Extracellular Vesicles (EVs), which convey their molecular cargo to neighboring or distant cells influencing their metabolism. Besides their involvement in the intercellular communication, EVs might represent a tool used by cells to eliminate unnecessary/toxic material. Here, we revised the literature exploring the link between EVs and redox biology. The first proof of this link derives from evidence demonstrating that EVs from healthy cells protect target cells from oxidative insults through the transfer of antioxidants. Oxidative stress conditions influence the release and the molecular cargo of EVs that, in turn, modulate the redox status of target cells. Oxidative stress-related EVs exert both beneficial or harmful effects, as they can carry antioxidants or ROS-generating enzymes and oxidized molecules. As mediators of cell-to-cell communication, EVs are also implicated in the pathophysiology of oxidative stress-related diseases. The review found evidence that numerous studies speculated on the role of EVs in redox signaling and oxidative stress-related pathologies, but few of them unraveled molecular mechanisms behind this complex link. Thus, the purpose of this review is to report and discuss this evidence, highlighting that the analysis of the molecular content of oxidative stress-released EVs (reminiscent of the redox status of originating cells), is a starting point for the use of EVs as diagnostic and therapeutic tools in oxidative stress-related diseases.