Activation of Nrf2 by miR-152 Inhibits Doxorubicin-Induced Cardiotoxicity via Attenuation of Oxidative Stress, Inflammation, and Apoptosis

Targeting Nrf2 signaling pathway: new therapeutic strategy for cardiovascular diseases

Cardiovascular diseases (CVDs) are the leading cause of death globally, with oxidative stress (OS) identified as a primary contributor to their onset and progression. Given the elevated incidence and mortality rates associated with CVDs, there is an imperative need to investigate novel therapeutic strategies. Nuclear factor erythroid 2-related factor 2 (Nrf2), ubiquitously expressed in the cardiovascular system, has emerged as a promising therapeutic target for CVDs due to its role in regulating OS and inflammation. This review aims to delve into the mechanisms and actions of the Nrf2 pathway, highlighting its potential in mitigating the pathogenesis of CVDs.

The role and mechanism of epigenetics in anticancer drug-induced cardiotoxicity

Cardiovascular disease is the main factor contributing to the global burden of diseases, and the cardiotoxicity caused by anticancer drugs is an essential component that cannot be ignored. With the development of anticancer drugs, the survival period of cancer patients is prolonged; however, the cardiotoxicity caused by anticancer drugs is becoming increasingly prominent. Currently, cardiovascular disease has emerged as the second leading cause of mortality among long-term cancer survivors. Anticancer drug-induced cardiotoxicity has become a frontier and hot topic. The discovery of epigenetics has given the possibility of environmental changes in gene expression, protein synthesis, and traits. It has been found that epigenetics plays a pivotal role in promoting cardiovascular diseases, such as heart failure, coronary heart disease, and hypertension. In recent years, increasing studies have underscored the crucial roles played by epigenetics in anticancer drug-induced cardiotoxicity. Here, we provide a comprehensive overview of the role and mechanisms of epigenetics in anticancer drug-induced cardiotoxicity.

Recent progress in the role of endogenous metal ions in doxorubicin-induced cardiotoxicity

Doxorubicin is a widely used anticancer drug in clinical practice for the treatment of various human tumors. However, its administration is associated with cardiotoxicity. Administration of doxorubicin with low side effects for cancer treatment and prevention are, accordingly, urgently required. The human body harbors various endogenous metal ions that exert substantial influences. Consequently, extensive research has been conducted over several decades to investigate the potential of targeting endogenous metal ions to mitigate doxorubicin's side effects and impede tumor progression. In recent years, there has been a growing body of research indicating the potential efficacy of metal ion-associated therapeutic strategies in inhibiting doxorubicin-induced cardiotoxicity (DIC). These strategies offer a combination of favorable safety profiles and potential clinical utility. Alterations in intracellular levels of metal ions have been found to either facilitate or mitigate the development of DIC. For instance, ferroptosis, a cellular death mechanism, and metal ions such as copper, zinc, and calcium have been identified as significant contributors to DIC. This understanding can contribute to advancements in cancer treatment and provide valuable insights for mitigating the cardiotoxic effects of other therapeutic drugs. Furthermore, potential therapeutic strategies have been investigated to alleviate DIC in clinical settings. The ultimate goal is to improve the efficacy and safety of Dox and offer valuable insights for future research in this field.

MiR-494-3p aggravates pirarubicin-induced cardiomyocyte injury by regulating MDM4/p53 signaling pathway

OBJECTIVE

Pirarubicin (THP) is a widely used antitumor drug in clinical practice, but its cardiotoxicity limits its use. There is an urgent need to find drugs to alleviate the cardiotoxicity of THP. This study aimed to investigate the effect and mechanism of miR-494-3p on THP-induced cardiomyocytes.

METHODS

THP induced immortalized mouse cardiomyocytes HL-1, silenced or overexpressed miR-494-3p. The effects of miR-494-3p on HL-1 contained in THP were investigated by CCK8, flow cytometry, ROS detection, JC-1 mitochondrial membrane potential detection, TUNEL cell apoptosis detection, RT-qPCR, and Western blot.

RESULTS

miR-494-3p could reduce cell viability, increase oxidative damage, and promote cell apoptosis; at the same time, it inhibited the expression of MDM4, promoted the activation of p53, and promoted the expression of apoptosis-related proteins. MiR-494-3p inhibitors have the opposite effect.

CONCLUSION

miR-494-3p can aggravate THP damage to HL-1, which may be achieved by downregulating MDM4 and promoting p53. miR-494-3p is one of the important miRNAs in THP-induced cardiotoxicity, which provides theoretical support for its possible use as a therapeutic target for THP-induced cardiovascular disease.

miR-200a attenuated oxidative stress, inflammation, and apoptosis in dextran sulfate sodium-induced colitis through activation of Nrf2

Introduction

Oxidative stress and inflammatory responses are critical factors in ulcerative colitis disease pathogenesis. Nuclear factor erythroid 2-related factor 2 (Nrf2) modulates oxidative stress and suppresses inflammatory responses, and the protective benefits of Nrf2 activation have been associated with the therapy of ulcerative colitis. MicroRNA-200a (miR-200a) could target Kelch-like ECH-associated protein 1 (Keap1) and activate the Nrf2-regulated antioxidant pathway. Nevertheless, whether miR-200a modulates the Keap1/Nrf2 pathway in dextran sulfate sodium (DSS)-induced colonic damage is unknown. Here, our research intends to examine the impact of miR-200a in the model of DSS-induced colitis.

Methods

Prior to DSS intervention, we overexpressed miR-200a in mice for four weeks using an adeno-associated viral (AAV) vector to address this problem. ELISA detected the concentration of inflammation-related cytokines. The genes involved in inflammatory reactions and oxidative stress were identified using quantitative reverse transcription-polymerase chain reaction (qRT-PCR), western blot, and immunofluorescence. Moreover, we applied siRNAs to weakened Nrf2 expression to confirm the hypothesis that miR-200a provided protection via Nrf2.

Results

The present study discovered miR-200a down-regulation, excessive inflammatory activation, enterocyte apoptosis, colonic dysfunction, and Keap1/Nrf2 antioxidant pathway inactivation in mouse colitis and NCM460 cells under DSS induction. However, our data demonstrated that miR-200a overexpression represses Keap1 and activates the Nrf2 antioxidant pathway, thereby alleviating these adverse alterations in animal and cellular models. Significantly, following Nrf2 deficiency, we failed to observe the protective benefits of miR-200a against colonic damage.

Discussion

Taken together, through activating the Keap1/Nrf2 signaling pathway, miR-200a protected against DSS-induced colonic damage. These studies offer an innovative therapeutic approach for ulcerative colitis.

Nrf2: a dark horse in doxorubicin-induced cardiotoxicity

Being a broad-spectrum anticancer drug, doxorubicin is indispensable for clinical treatment. Unexpectedly, its cardiotoxic side effects have proven to be a formidable obstacle. Numerous studies are currently devoted to elucidating the pathological mechanisms underlying doxorubicin-induced cardiotoxicity. Nrf2 has always played a crucial role in oxidative stress, but numerous studies have demonstrated that it also plays a vital part in pathological mechanisms like cell death and inflammation. Numerous studies on the pathological mechanisms associated with doxorubicin-induced cardiotoxicity demonstrate this. Several clinical drugs, natural and synthetic compounds, as well as small molecule RNAs have been demonstrated to prevent doxorubicin-induced cardiotoxicity by activating Nrf2. Consequently, this study emphasizes the introduction of Nrf2, discusses the role of Nrf2 in doxorubicin-induced cardiotoxicity, and concludes with a summary of the therapeutic modalities targeting Nrf2 to ameliorate doxorubicin-induced cardiotoxicity, highlighting the potential value of Nrf2 in doxorubicin-induced cardiotoxicity.

MicroRNAs target the PI3K/Akt/p53 and the Sirt1/Nrf2 signaling pathways in doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is used as a chemotherapeutic agent in the treatment of solid tumors. Irreversible cardiotoxicity is the major limitation in the clinical use of DOX. Several microRNAs (miRNAs) with diversified functions are identified that participate in exacerbating or suppressing DOX-induced cardiac damage. The miRNAs are small noncoding regulatory RNAs that modify the expression of the native genes. Studies have demonstrated that miRNAs by modifying the expression of proteins such as PTEN, Akt, and survivin can affect DOX-induced cardiac apoptosis. Moreover, miRNAs can modulate cardiac oxidative stress in DOX treatment through the posttranscriptional regulation of Sirt1, p66shc, and Nrf2 expressions. This manuscript has reviewed the regulation of the PI3K/Akt/p53 and the Sirt1/Nrf2 pathways by miRNAs in DOX-induced cardiotoxicity.

Identification of novel biomarkers involved in doxorubicin-induced acute and chronic cardiotoxicity, respectively, by integrated bioinformatics

Background

The mechanisms of doxorubicin (DOX) cardiotoxicity were complex and controversial, with various contradictions between experimental and clinical data. Understanding the differences in the molecular mechanism between DOX-induced acute and chronic cardiotoxicity may be an ideal entry point to solve this dilemma.

Methods

Mice were injected intraperitoneally with DOX [(20 mg/kg, once) or (5 mg/kg/week, three times)] to construct acute and chronic cardiotoxicity models, respectively. Survival record and ultrasound monitored the cardiac function. The corresponding left ventricular (LV) myocardium tissues were analyzed by RNA-seq to identify differentially expressed genes (DEGs). Gene Ontology (GO), Kyoto Encyclopedia of Gene and Genome (KEGG), and Gene Set Enrichment Analysis (GSEA) found the key biological processes and signaling pathways. DOX cardiotoxicity datasets from the Gene expression omnibus (GEO) database were combined with RNA-seq to identify the common genes. Cytoscape analyzed the hub genes, which were validated by quantitative real-time PCR. ImmuCo and ImmGen databases analyzed the correlations between hub genes and immunity-relative markers in immune cells. Cibersort analyzed the immune infiltration and correlations between the hub genes and the immune cells. Logistic regression, receiver operator characteristic curve, and artificial neural network analysis evaluated the diagnosis ability of hub genes for clinical data in the GEO dataset.

Results

The survival curves and ultrasound monitoring demonstrated that cardiotoxicity models were constructed successfully. In the acute model, 788 DEGs were enriched in the activated metabolism and the suppressed immunity-associated signaling pathways. Three hub genes (Alas1, Atp5g1, and Ptgds) were upregulated and were negatively correlated with a colony of immune-activating cells. However, in the chronic model, 281 DEGs showed that G protein-coupled receptor (GPCR)-related signaling pathways were the critical events. Three hub genes (Hsph1, Abcb1a, and Vegfa) were increased in the chronic model. Furthermore, Hsph1 combined with Vegfa was positively correlated with dilated cardiomyopathy (DCM)-induced heart failure (HF) and had high accuracy in the diagnosis of DCM-induced HF (AUC = 0.898, P = 0.000).

Conclusion

Alas1, Atp5g1, and Ptgds were ideal biomarkers in DOX acute cardiotoxicity. However, Hsph1 and Vegfa were potential biomarkers in the myocardium in the chronic model. Our research, first, provided bioinformatics and clinical evidence for the discovery of the differences in mechanism and potential biomarkers of DOX-induced acute and chronic cardiotoxicity to find a therapeutic strategy precisely.

Activation of Nrf2 signaling: A key molecular mechanism of protection against cardiovascular diseases by natural products

Cardiovascular diseases (CVD) are a group of cardiac and vascular disorders including myocardial ischemia, congenital heart disease, heart failure, hypertension, atherosclerosis, peripheral artery disease, rheumatic heart disease, and cardiomyopathies. Despite considerable progress in prophylaxis and treatment options, CVDs remain a leading cause of morbidity and mortality and impose an extremely high socioeconomic burden. Oxidative stress (OS) caused by disequilibrium in the generation of reactive oxygen species plays a crucial role in the pathophysiology of CVDs. Nuclear erythroid 2-related factor 2 (Nrf2), a transcription factor of endogenous antioxidant defense systems against OS, is considered an ideal therapeutic target for management of CVDs. Increasingly, natural products have emerged as a potential source of Nrf2 activators with cardioprotective properties and may therefore provide a novel therapeutic tool for CVD. Here, we present an updated comprehensive summary of naturally occurring products with cardioprotective properties that exert their effects by suppression of OS through activation of Nrf2 signaling, with the aim of providing useful insights for the development of therapeutic strategies exploiting natural products.

MicroRNAs in doxorubicin-induced cardiotoxicity: The DNA damage response

Doxorubicin (DOX) is a chemotherapeutic drug widely used for cancer treatment, but its use is limited by cardiotoxicity. Although free radicals from redox cycling and free cellular iron have been predominant as the suggested primary pathogenic mechanism, novel evidence has pointed to topoisomerase II inhibition and resultant genotoxic stress as the more fundamental mechanism. Recently, a growing list of microRNAs (miRNAs) has been implicated in DOX-induced cardiotoxicity (DIC). This review summarizes miRNAs reported in the recent literature in the context of DIC. A particular focus is given to miRNAs that regulate cellular responses downstream to DOX-induced DNA damage, especially p53 activation, pro-survival signaling pathway inhibition (e.g., AMPK, AKT, GATA-4, and sirtuin pathways), mitochondrial dysfunction, and ferroptosis. Since these pathways are potential targets for cardioprotection against DOX, an understanding of how miRNAs participate is necessary for developing future therapies.

Non-coding RNAs in cancer therapy-induced cardiotoxicity: Mechanisms, biomarkers, and treatments

As a result of ongoing breakthroughs in cancer therapy, cancer patients' survival rates have grown considerably. However, cardiotoxicity has emerged as the most dangerous toxic side effect of cancer treatment, negatively impacting cancer patients' prognosis. In recent years, the link between non-coding RNAs (ncRNAs) and cancer therapy-induced cardiotoxicity has received much attention and investigation. NcRNAs are non-protein-coding RNAs that impact gene expression post-transcriptionally. They include microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). In several cancer treatments, such as chemotherapy, radiotherapy, and targeted therapy-induced cardiotoxicity, ncRNAs play a significant role in the onset and progression of cardiotoxicity. This review focuses on the mechanisms of ncRNAs in cancer therapy-induced cardiotoxicity, including apoptosis, mitochondrial damage, oxidative stress, DNA damage, inflammation, autophagy, aging, calcium homeostasis, vascular homeostasis, and fibrosis. In addition, this review explores potential ncRNAs-based biomarkers and therapeutic strategies, which may help to convert ncRNAs research into clinical practice in the future for early detection and improvement of cancer therapy-induced cardiotoxicity.

DNA methyltransferase 1 (DNMT1) suppresses mitophagy and aggravates heart failure via the microRNA-152-3p/ETS1/RhoH axis

DNA methyltransferase 1 (DNMT1) shows close link with heart disease. This study aimed to define the role DNMT1 plays in heart failure and determine the underlying mechanism. Expression of microRNA (miR)-152-3p, DNMT1, E26 transformation specific-1 (ETS1) and ras homolog gene family member H (RhoH) was determined by RT-qPCR and/or western blot analysis. The interaction between miR-152-3p and ETS1 was predicted and verified. Methylation of the miR-152-3p promoter region was assessed using methylation-specific PCR. H9c2 cells were chosen for in vitro assays to examine the regulatory role of DNMT1 in autophagy and mitophagy with respect to miR-152-3p/ETS1/RhoH. Doxorubicin (DOX)-induced rat models of heart failure were employed for in vivo validation. DNMT1 expression was upregulated in the heart tissues of DOX-induced rats, where it showed an inverse correlation with miR-152-3p expression. Moreover, DNMT1 was shown to enhance methylation of the miR-152-3p promoter region and suppress its expression, leading to inhibition of mitophagy in H9c2 cells. In addition, DNMT1 enhanced expression of ETS1, which further elevated RhoH expression. Moreover, ETS1-elevated RhoH reduced cell viability and promoted autophagy and mitophagy in H9c2 cells upon treatment with DOX. Next, in vivo results demonstrated that depletion of DNMT1 protected rats from heart failure in a miR-152-3p/ETS1/RhoH-dependent manner. Overall, these findings indicate that DNMT1 may inhibit expression of miR-152-3p by promoting the methylation of miR-152-3p and enhancing the expression of ETS1, thereby inducing RHOH transcriptional activation and inhibiting mitochondrial autophagy, ultimately promoting the development of heart failure.

The Therapeutic Potential of Carnosine as an Antidote against Drug-Induced Cardiotoxicity and Neurotoxicity: Focus on Nrf2 Pathway

Different drug classes such as antineoplastic drugs (anthracyclines, cyclophosphamide, 5-fluorouracil, taxanes, tyrosine kinase inhibitors), antiretroviral drugs, antipsychotic, and immunosuppressant drugs are known to induce cardiotoxic and neurotoxic effects. Recent studies have demonstrated that the impairment of the nuclear factor erythroid 2–related factor 2 (Nrf2) pathway is a primary event in the pathophysiology of drug-induced cardiotoxicity and neurotoxicity. The Nrf2 pathway regulates the expression of different genes whose products are involved in antioxidant and inflammatory responses and the detoxification of toxic species. Cardiotoxic drugs, such as the anthracycline doxorubicin, or neurotoxic drugs, such as paclitaxel, suppress or impair the Nrf2 pathway, whereas the rescue of this pathway counteracts both the oxidative stress and inflammation that are related to drug-induced cardiotoxicity and neurotoxicity. Therefore Nrf2 represents a novel pharmacological target to develop new antidotes in the field of clinical toxicology. Interestingly, carnosine (β-alanyl-l-histidine), an endogenous dipeptide that is characterized by strong antioxidant, anti-inflammatory, and neuroprotective properties is able to rescue/activate the Nrf2 pathway, as demonstrated by different preclinical studies and preliminary clinical evidence. Starting from these new data, in the present review, we examined the evidence on the therapeutic potential of carnosine as an endogenous antidote that is able to rescue the Nrf2 pathway and then counteract drug-induced cardiotoxicity and neurotoxicity.

The microRNA Expression Profiling in Heart Failure: A Systematic Review and Meta-Analysis

Background

Heart failure (HF) is a main consequence of cardiovascular diseases worldwide. Abnormal expression levels of microRNAs (miRNAs) in HF are observed in current studies. Novel biomarkers miRNAs may play an important role in the development of HF. Nevertheless, the inconsistency of miRNA expression limits the clinical application. We thus perform this systematic review of the miRNAs expression profiling to identify potential HF biomarkers.

Methods

The electronic databases of Embase, Medline, and Cochrane Library were systematically searched to identify the miRNA expression profiles between HF subjects and non-HF controls before May 26th, 2021. The pooled results were shown as log10 odds ratios (logORs) with 95% confidence intervals (CI) using random-effect models. Subgroup analyses were conducted according to species, region, and sample source. The quality assessment of included studies was independently conducted based on Diagnostic Accuracy Study 2 (QUADAS-2). The sensitivity analysis was conducted based on sample size.

Results

A total of 55 miRNA expression articles reporting 276 miRNAs of HF were included. 47 consistently up-regulated and 10 down-regulated miRNAs were identified in the overall analysis, with the most up-regulated miR-21 (logOR 8.02; 95% CI: 6.76–9.27, P < 0.001) and the most down-regulated miR-30c (logOR 6.62; 95% CI: 3.04–10.20, P < 0.001). The subgroup analysis of sample source identified 35 up-regulated and 10 down-regulated miRNAs in blood sample, the most up-regulated and down-regulated miRNAs were miR-210-3p and miR-30c, respectively. In the region sub-groups, let-7i-5p and miR-129 were most up-regulated and down-regulated in Asian countries, while in non-Asian countries, let-7e-5p and miR-30c were the most dysregulated. It’s worth noting that miR-622 was consistently up-regulated in both Asian and non-Asian countries. Sensitivity analysis showed that 46 out of 58 (79.31%) miRNAs were dysregulated.

Conclusion

A total of 57 consistently dysregulated miRNAs related to HF were confirmed in this study. Seven dysregulated miRNAs (miR-21, miR-30c, miR-210-3p, let-7i-5p, miR-129, let-7e-5p, and miR-622) may be considered as potential non-invasive biomarkers for HF. However, further validation in larger-scale studies are needed to verify our conclusions.

Role of Oxidative Stress in Diabetic Cardiomyopathy

Type 2 diabetes is a redox disease. Oxidative stress and chronic inflammation induce a switch of metabolic homeostatic set points, leading to glucose intolerance. Several diabetes-specific mechanisms contribute to prominent oxidative distress in the heart, resulting in the development of diabetic cardiomyopathy. Mitochondrial overproduction of reactive oxygen species in diabetic subjects is not only caused by intracellular hyperglycemia in the microvasculature but is also the result of increased fatty oxidation and lipotoxicity in cardiomyocytes. Mitochondrial overproduction of superoxide anion radicals induces, via inhibition of glyceraldehyde 3-phosphate dehydrogenase, an increased polyol pathway flux, increased formation of advanced glycation end-products (AGE) and activation of the receptor for AGE (RAGE), activation of protein kinase C isoforms, and an increased hexosamine pathway flux. These pathways not only directly contribute to diabetic cardiomyopathy but are themselves a source of additional reactive oxygen species. Reactive oxygen species and oxidative distress lead to cell dysfunction and cellular injury not only via protein oxidation, lipid peroxidation, DNA damage, and oxidative changes in microRNAs but also via activation of stress-sensitive pathways and redox regulation. Investigations in animal models of diabetic cardiomyopathy have consistently demonstrated that increased expression of the primary antioxidant enzymes attenuates myocardial pathology and improves cardiac function.

Long non-coding RNAs and microRNAs as crucial regulators in cardio-oncology

Cancer is one of the leading causes of morbidity and mortality worldwide. Significant improvements in the modern era of anticancer therapeutic strategies have increased the survival rate of cancer patients. Unfortunately, cancer survivors have an increased risk of cardiovascular diseases, which is believed to result from anticancer therapies. The emergence of cardiovascular diseases among cancer survivors has served as the basis for establishing a novel field termed cardio-oncology. Cardio-oncology primarily focuses on investigating the underlying molecular mechanisms by which anticancer treatments lead to cardiovascular dysfunction and the development of novel cardioprotective strategies to counteract cardiotoxic effects of cancer therapies. Advances in genome biology have revealed that most of the genome is transcribed into non-coding RNAs (ncRNAs), which are recognized as being instrumental in cancer, cardiovascular health, and disease. Emerging studies have demonstrated that alterations of these ncRNAs have pathophysiological roles in multiple diseases in humans. As it relates to cardio-oncology, though, there is limited knowledge of the role of ncRNAs. In the present review, we summarize the up-to-date knowledge regarding the roles of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in cancer therapy-induced cardiotoxicities. Moreover, we also discuss prospective therapeutic strategies and the translational relevance of these ncRNAs.

miR-488-3p Protects Cardiomyocytes against Doxorubicin-Induced Cardiotoxicity by Inhibiting CyclinG1

Objective

To investigate the protective effects and regulatory mechanism of miR-488-3p on doxorubicin-induced cardiotoxicity.

Methods

The C57BL/6 mice and primary cardiomyocytes were used to construct doxorubicin-induced cardiomyocyte injury models in vivo and in vitro. The levels of miR-488-3p and its downstream target genes were analyzed by quantitative real-time PCR. Mouse cardiac function, cell survival, cellular injury-related proteins, and the apoptosis level of cardiomyocytes were analyzed by echocardiography, MTT analysis, Western blotting, and DNA laddering separately.

Results

Cardiomyocyte injury caused by a variety of stimuli can lead to the reduction of miR-488-3p level, especially when stimulated with doxorubicin. Doxorubicin led to significant decrease in cardiac function, cell autophagic flux blockage, and apoptosis in vivo and in vitro. The expression of miR-488-3p's target gene, CyclinG1, increased remarkably in the doxorubicin-treated neonatal mouse cardiomyocytes. Overexpression of miR-488-3p inhibited CyclinG1 expression, increased cardiomyocyte viability, and attenuated doxorubicin-induced cardiomyocyte autophagic flux blockage and apoptosis.

Conclusions

miR-488-3p is one of the important protective miRNAs in doxorubicin-induced cardiotoxicity by inhibiting the expression of CyclinG1, which provides insight into the possible clinical application of miR-488-3p/CyclinG1 as therapeutic targets in doxorubicin-induced cardiovascular diseases.

MicroRNAs as Biomarkers and Therapeutic Targets in Doxorubicin-Induced Cardiomyopathy: A Review

Doxorubicin is a broad-spectrum chemotherapy drug applied in antitumor therapy. However, its clinical utility is limited by its fatal cardiotoxicity. Doxorubicin (DOX)-induced cardiomyopathy (DIC) begins with the first DOX dose and is characterized by being cumulative dose-dependent, and its early diagnosis using common detection methods is very difficult. Therefore, it is urgent to determine the underlying mechanism of DIC to construct treatment strategies for the early intervention before irreversible damage to the myocardium occurs. Growing evidence suggests that microRNAs (miRNAs) play regulatory roles in the cardiovascular system. miRNAs may be involved in DIC by acting through multiple pathways to induce cardiomyocyte injury. Recent studies have shown that the dysregulation of miRNA expression can aggravate the pathological process of DIC, including the induction of oxidative stress, apoptosis, ion channel dysfunction and microvascular dysfunction. Current findings on the roles of miRNAs in DIC have led to a wide range of studies exploring candidate miRNAs to be utilized as diagnostic biomarkers and potential therapeutic targets for DIC. In this review, we discuss frontier studies on the roles of miRNAs in DIC to better understand their functions, develop relevant applications in DIC, discuss possible reasons for the limitations of their use and speculate on innovative treatment strategies.

Targeting Oxidative Stress, NLRP3 Inflammasome, and Autophagy by Fraxetin to Combat Doxorubicin-Induced Cardiotoxicity

Doxorubicin belongs to the class of anthracycline antibiotics that is widely used in the treatment protocols of a wide range of malignancies. The major deleterious effect of doxorubicin use is the possible occurrence of cardiotoxicity. This study aimed to delineate the possible effects of targeting oxidative stress, NLRP3 inflammasome, and autophagy by fraxetin on doxorubicin-induced cardiac dysfunction in rats. In a model of doxorubicin-induced cardiotoxicity, the effects of different doses of fraxetin were assessed by determination of biochemical, histopathological, immunohistochemical, and electron microscopic changes. Fraxetin, in a dose-dependent manner, was found to have the ability to mitigate the harmful effects of oxidative stress and inflammation on myocardial muscles with significant decrease in NLRP3 inflammasome, augmentation of autophagy, and amelioration of the apoptotic signaling pathways. In addition, fraxetin, in a dose-dependent manner, had the ability to combat the echocardiographic, histopathological, immunohistochemical, and electron microscopic changes induced by doxorubicin in cardiomyocytes. As a result, fraxetin may be put into consideration as a new adjuvant line of therapy on the way to mitigate doxorubicin-induced cardiotoxicity.

Circ-Usp10 promotes microglial activation and induces neuronal death by targeting miRNA-152-5p/CD84

Spinal cord injury (SCI) is a traumatic disease resulting in neuronal injury. circRNAs are closely associated with human diseases. Nevertheless, the potential mechanism by which circRNAs impact SCI remains to be elucidated. The aim of this study was to investigate the regulatory roles of Circular RNAs (circRNAs) in SCI. The SCI mouse model and integrated bioinformatics analysis were used to identify the differentially expressed genes (DEGs). Functional enrichment analysis was conducted to study the related pathways. The circRNA-mediated ceRNA network and subnetwork was constructed based on circMir, TargetScan and miRanda. qRT–PCR, ELISA, flow cytometry, and luciferase reporter assays were carried out to validate the role of circ_0014637 (circ-Usp10) and microRNA(miR)-152-5p /CD84 in microglia. In all, 23 DE-circRNAs, 127 DE-miRNAs and 1327 DE-mRNAs were identified. We integrated these DEGs to construct a circRNA-miRNA-mRNA network. The circ-Usp10/miR-152-5p/CD84 axis was found to function in microglial activation. We also found that circ-Usp10 inhibited the secretion of proinflammatory factors in microglial BV2 cells. In addition, silencing circ-Usp10 significantly reduced the death of the neuronal cell line HT22. Taken together, we concluded that circ-Usp10 may function as a competing endogenous RNA (ceRNA) to promote microglial activation and induce neuronal death by targeting miR-152-5p/CD84. The circ-Usp10 may be a diagnostic biomarker and potential target for SCI therapy.

Role of Oxidative Stress in Heart Failure: Insights from Gene Transfer Studies

Under physiological circumstances, there is an exquisite balance between reactive oxygen species (ROS) production and ROS degradation, resulting in low steady-state ROS levels. ROS participate in normal cellular function and in cellular homeostasis. Oxidative stress is the state of a transient or a persistent increase of steady-state ROS levels leading to disturbed signaling pathways and oxidative modification of cellular constituents. It is a key pathophysiological player in pathological hypertrophy, pathological remodeling, and the development and progression of heart failure. The heart is the metabolically most active organ and is characterized by the highest content of mitochondria of any tissue. Mitochondria are the main source of ROS in the myocardium. The causal role of oxidative stress in heart failure is highlighted by gene transfer studies of three primary antioxidant enzymes, thioredoxin, and heme oxygenase-1, and is further supported by gene therapy studies directed at correcting oxidative stress linked to metabolic risk factors. Moreover, gene transfer studies have demonstrated that redox-sensitive microRNAs constitute potential therapeutic targets for the treatment of heart failure. In conclusion, gene therapy studies have provided strong corroborative evidence for a key role of oxidative stress in pathological remodeling and in the development of heart failure.

The Role of microRNAs in Pulp Inflammation

The dental pulp can be affected by thermal, physical, chemical, and bacterial phenomena that stimulate the inflammatory response. The pulp tissue produces an immunological, cellular, and vascular reaction in an attempt to defend itself and resolve the affected tissue. The expression of different microRNAs during pulp inflammation has been previously documented. MicroRNAs (miRNAs) are endogenous small molecules involved in the transcription of genes that regulate the immune system and the inflammatory response. They are present in cellular and physiological functions, as well as in the pathogenesis of human diseases, becoming potential biomarkers for diagnosis, prognosis, monitoring, and safety. Previous studies have evidenced the different roles played by miRNAs in proinflammatory, anti-inflammatory, and immunological phenomena in the dental pulp, highlighting specific key functions of pulp pathology. This systematized review aims to provide an understanding of the role of the different microRNAs detected in the pulp and their effects on the expression of the different target genes that are involved during pulp inflammation.

AQP3 and AQP5-Potential Regulators of Redox Status in Breast Cancer

Breast cancer is still one of the leading causes of mortality in the female population. Despite the campaigns for early detection, the improvement in procedures and treatment, drastic improvement in survival rate is omitted. Discovery of aquaporins, at first described as cellular plumbing system, opened new insights in processes which contribute to cancer cell motility and proliferation. As we discover new pathways activated by aquaporins, the more we realize the complexity of biological processes and the necessity to fully understand the pathways affected by specific aquaporin in order to gain the desired outcome-remission of the disease. Among the 13 human aquaporins, AQP3 and AQP5 were shown to be significantly upregulated in breast cancer indicating their role in the development of this malignancy. Therefore, these two aquaporins will be discussed for their involvement in breast cancer development, regulation of oxidative stress and redox signalling pathways leading to possibly targeting them for new therapies.