Autophagy in cardiovascular diseases: role of noncoding RNAs

Crosstalk between ubiquitin ligases and ncRNAs drives cardiovascular disease progression

Cardiovascular diseases (CVDs) are multifactorial chronic diseases and have the highest rates of morbidity and mortality worldwide. The ubiquitin-proteasome system (UPS) plays a crucial role in posttranslational modification and quality control of proteins, maintaining intracellular homeostasis via degradation of misfolded, short-lived, or nonfunctional regulatory proteins. Noncoding RNAs (ncRNAs, such as microRNAs, long noncoding RNAs, circular RNAs and small interfering RNAs) serve as epigenetic factors and directly or indirectly participate in various physiological and pathological processes. NcRNAs that regulate ubiquitination or are regulated by the UPS are involved in the execution of target protein stability. The cross-linked relationship between the UPS, ncRNAs and CVDs has drawn researchers' attention. Herein, we provide an update on recent developments and perspectives on how the crosstalk of the UPS and ncRNAs affects the pathological mechanisms of CVDs, particularly myocardial ischemia/reperfusion injury, myocardial infarction, cardiomyopathy, heart failure, atherosclerosis, hypertension, and ischemic stroke. In addition, we further envision that RNA interference or ncRNA mimics or inhibitors targeting the UPS can potentially be used as therapeutic tools and strategies.

Cardiac regeneration: Pre-existing cardiomyocyte as the hub of novel signaling pathway

In the mammalian heart, cardiomyocytes are forced to withdraw from the cell cycle shortly after birth, limiting the ability of the heart to regenerate and repair. The development of multimodal regulation of cardiac proliferation has verified that pre-existing cardiomyocyte proliferation is an essential driver of cardiac renewal. With the continuous development of genetic lineage tracking technology, it has been revealed that cell cycle activity produces polyploid cardiomyocytes during the embryonic, juvenile, and adult stages of cardiogenesis, but newly formed mononucleated diploid cardiomyocytes also elevated sporadically during myocardial infarction. It implied that adult cardiomyocytes have a weak regenerative capacity under the condition of ischemia injury, which offers hope for the clinical treatment of myocardial infarction. However, the regeneration frequency and source of cardiomyocytes are still low, and the mechanism of regulating cardiomyocyte proliferation remains further explained. It is noteworthy to explore what force triggers endogenous cardiomyocyte proliferation and heart regeneration. Here, we focused on summarizing the recent research progress of emerging endogenous key modulators and crosstalk with other signaling pathways and furnished valuable insights into the internal mechanism of heart regeneration. In addition, myocardial transcription factors, non-coding RNAs, cyclins, and cell cycle-dependent kinases are involved in the multimodal regulation of pre-existing cardiomyocyte proliferation. Ultimately, awakening the myocardial proliferation endogenous modulator and regeneration pathways may be the final battlefield for the regenerative therapy of cardiovascular diseases.

Screening and Validation of Key Genes of Autophagy in Acute Myocardial Infarction Based on Bioinformatics

Aims

Autophagy plays a significant role in the development of acute myocardial infarction (AMI), and cardiomyocyte autophagy is of major importance in maintaining cardiac function. We aimed to identify key genes associated with autophagy in AMI through bioinformatics analysis and verify them through clinical validation.

Materials and Methods

We downloaded an AMI expression profile dataset GSE166780 from Gene Expression Omnibus (GEO). Autophagy-associated genes potentially differentially expressed in AMI were screened using R software. Then, to identify key autophagy-related genes, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, protein-protein interaction (PPI) analysis, Receiver Operating Characteristic (ROC) curve analysis, and correlation analysis were performed on the differentially expressed autophagy-related genes in AMI. Finally, we used quantificational real-time polymerase chain reaction (qRT-PCR) to verify the RNA expression of the screened key genes.

Results

TSC2, HSPA8, and HIF1A were screened out as key autophagy-related genes. qRT-PCR results showed that the expression levels of HSPA8 and TSC2 in AMI blood samples were lower, while the expression level of HIF1A was higher than that in the healthy controls.

Conclusions

TSC2, HSPA8, and HIF1A were identified as key autophagy-related genes in this study. They may influence the development of AMI through autophagy. These findings may help deepen our understanding of AMI and may be useful for the treatment of AMI.

Blood Homocysteine Levels Mediate the Association Between Blood Lead Levels and Cardiovascular Mortality

Lead is a heavy, toxic metal and its exposure to humans can lead to increased risk of cardiovascular disease development and mortality. Lead exposure has been shown to induce hyperhomocysteinemia (HHCy) which may be a major pathogenic risk for the risk of CVDs. The aim of this study was to investigate whether homocysteine (Hcy) mediates the effect of lead on cardiovascular mortality. A total of 17,915 adults aged ≥ 20 who participated in the National Health and Nutrition Examination Survey (1999 to 2006). Information on mortality was ascertained via probabilistic matching to the death certificates from the National Death Index recorded up to December 31, 2015. Cox proportional hazards regression was performed to assess the association between blood lead levels and mortality. Mediation via Hcy was examined using a logit model. During a mean follow-up of 11.6 years, the incidences of CVD mortality were 0.73, 2.18, 3.03 and 4.94 per 1000 person-years across quarterlies of blood lead levels from low to high. Following multivariable adjustment, blood lead levels were strongly associated with CVD mortality in all mortality models (p-trend < 0.001). This association remained statistically significant after further adjusting for quartiles of homocysteine (model 3; HR 1.38 (95% CI 1.01-1.89) p-trend < 0.001). Furthermore, blood lead levels increased the odds of CVD mortality via homocysteine (indirect effect) (OR 1.42 (95% CI 1.30-1.55)), demonstrating the mediatory effect of homocysteine. This the first study that demonstrates that increased homocysteine mediates nearly half of CVD mortality related to blood lead levels.

Xiaojianzhong decoction attenuates aspirin-induced gastric mucosal injury via the PI3K/AKT/mTOR/ULK1 and AMPK/ULK1 pathways

CONTEXT

Xiaojianzhong decoction (XJZD), classically prescribed in Chinese medicine, has protective and healing effects on gastric mucosal injury. However, the exact mechanism behind this effect remains unclear.

OBJECTIVE

To investigate the effect of XJZD on gastric mucosal injury and explore its underlying mechanisms.

MATERIALS AND METHODS

C57BL/6 mice were randomized into six groups (n = 10): the control group receiving sterile water, the model (aspirin 300 mg/kg), the XJZD high-dose (12 g/kg), XJZD medium-dose (6 g/kg), XJZD low-dose (3 g/kg) and omeprazole (20 mg/kg) groups, by gavage daily for 14 days. The area of gastric mucosal injury, mucosal injury index and degree of histopathological damage were analysed. Gastric mucosal epithelial cell apoptosis was detected. Epithelial cell autophagy was observed. The expression levels of tight junction proteins and proteins related to apoptosis, autophagy and the pentose phosphate pathway were analysed.

RESULTS

The results showed that after treatment with XJZD (12, 6 and 3 g/kg), the mucosal injury area was reduced (83.4%, 22.6% and 11.3%), the expression level of ZO-1 and occludin was up-regulated, the apoptosis rate of epithelial cells was reduced (40.8%, 25.4% and 8.7%), the expression of autophagy-related proteins LC3 and Beclin1 was decreased and the expression of p62 was increased, the PI3K/AKT/mTOR/ULK1(ser757) signalling pathway was activated, and the AMPK/ULK1(ser317) signalling pathway was inhibited. In addition, XJZD can antagonize the imbalance of redox homeostasis caused by aspirin and protect the gastric mucosa.

DISCUSSION AND CONCLUSIONS

XJZD protects against aspirin-induced gastric mucosal injury, implying it to be a potential therapeutic agent.

Impact of Cerium Oxide Nanoparticles on Metabolic, Apoptotic, Autophagic and Antioxidant Changes in Doxorubicin-Induced Cardiomyopathy: Possible Underlying Mechanisms

Background

In the current study, the effects of cerium oxide nanoparticles (nanocerium; NC) on doxorubicin (DOX)-induced cardiomyopathy and its possible underlying mechanisms were addressed.

Methods

32 adult male rats were allocated into 4 groups; i) control group, ii) NC group; rats received NC (0.2 mg/kg, i.p., daily), iii) DOX group; rats received DOX 4 mg/kg (2 injections with a 14-day interval), and iv) DOX+NC group as DOX but rats received NC. At the end of the experiment, ECG and ECHO recordings and assessments of the levels of cardiac enzymes (CK-MB, LDH), and myocardial oxidative stress (MDA, catalase, and GSH), the expression of LC3 and beclin1 (markers of autophagy), caspase3 (marker of apoptosis) by immunohistochemistry, the expression of acetyl-CoA carboxylase alpha (ACCA) by PCR, and 5'adenosine monophosphate-activated protein kinase (AMPK) levels in the heart tissues were performed.

Results

The DOX group displayed a prolonged corrected QT interval, an increase in cardiac enzymes (CK-MB and LDH), myocardial oxidative stress (high MDA with low catalase and GSH), expression of ACCA, caspase-3, beclin1, and LC3 in myocardial tissues, with reduction in myocardial AMPK levels, and myocardial contractility (low ejection fraction, and fractional shortening). On the other hand, administration of NC with DOX resulted in significant improvement of all studied parameters.

Conclusion

NC offers a cardioprotective effect against DOX-induced cardiomyopathy. This effect might be due to its antioxidant and antiapoptotic effects as well as to the modulation of autophagy and metabolic dysfunctions induced by DOX in the heart tissues.

Long non-coding RNA RMST serves as a diagnostic biomarker in patients with carotid artery stenosis and predicts the occurrence of cerebral ischemic event: A retrospective study

OBJECTIVES

The purpose of this retrospective study is to explore the diagnostic and prognostic roles of serum RMST in carotid artery stenosis (CAS).

METHODS

Serum levels of RMST were detected in CAS patients, and the relationship between degree of carotid stenosis and RMST levels was analyzed. The ROC curve was drawn to evaluate RMST value in predicting the risk of CAS. Then, all CAS patients received a 5-year follow-up. K-M curve was used to analyze the significance of RMST on prognosis of CAS patients. Multi-factor cox logistic regression analysis was conducted to evaluate independent factors for outcome of CAS patients.

RESULTS

An increased RMST expression was certified in CAS patients when compared with healthy controls. The increase of serum RMST expression was related to high degree of carotid stenosis. In addition, serum RMST was a possible diagnosis and an independent influencing factor of prognosis in patients with CAS.

CONCLUSIONS

Raised serum RMST level was found in patients with CAS. Detecting RMST expression levels was of high value for predicting the occurrence and outcomes in CAS.

Decoding the regulatory roles of non-coding RNAs in cellular metabolism and disease

Non-coding RNAs, including long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), are being studied extensively in a variety of fields. Their roles in metabolism have received increasing attention in recent years but are not yet clear. The regulation of glucose, fatty acid, and amino acid metabolism is an imperative physiological process that occurs in living organisms and takes part in cancer and cardiovascular diseases. Here, we summarize the important roles played by non-coding RNAs in glucose metabolism, fatty acid metabolism, and amino acid metabolism, as well as the mechanisms involved. We also summarize the therapeutic advances for non-coding RNAs in diseases such as obesity, cardiovascular disease, and some metabolic diseases. Overall, non-coding RNAs are indispensable factors in metabolism and have a significant role in the three major metabolisms, which may be exploited as therapeutic targets in the future.

Autophagy in striated muscle diseases

Impaired biomolecules and cellular organelles are gradually built up during the development and aging of organisms, and this deteriorating process is expedited under stress conditions. As a major lysosome-mediated catabolic process, autophagy has evolved to eradicate these damaged cellular components and recycle nutrients to restore cellular homeostasis and fitness. The autophagic activities are altered under various disease conditions such as ischemia-reperfusion cardiac injury, sarcopenia, and genetic myopathies, which impact multiple cellular processes related to cellular growth and survival in cardiac and skeletal muscles. Thus, autophagy has been the focus for therapeutic development to treat these muscle diseases. To develop the specific and effective interventions targeting autophagy, it is essential to understand the molecular mechanisms by which autophagy is altered in heart and skeletal muscle disorders. Herein, we summarize how autophagy alterations are linked to cardiac and skeletal muscle defects and how these alterations occur. We further discuss potential pharmacological and genetic interventions to regulate autophagy activities and their applications in cardiac and skeletal muscle diseases.

circ_0086296 induced atherosclerotic lesions via the IFIT1/STAT1 feedback loop by sponging miR-576-3p

Extensive inflammation of endothelial cells (ECs) facilitates atherosclerotic lesion formation. Circular RNA (circRNA) participates in atherosclerosis (AS)-related inflammation responses; however, whether and how circ_0086296 regulates atherosclerotic inflammation and lesions have not been investigated. Microarray analysis, quantitative real-time polymerase chain reaction, and fluorescence in situ hybridization assay were performed to detect the expression and location of hsa_circ_0086296 in human carotid artery plaques, aorta of atherosclerotic mice, and human umbilical vein endothelial cells (HUVECs). Sanger sequencing was used to verify the loop structure of circ_0086296. The relationship among circ_0086296, miR-576-3p, IFIT1, STAT1, and EIF4A3 was validated using bioinformatics, luciferase assay, RNA pull-down assay, and RNA immunoprecipitation. The atherosclerosis mouse model was used to evaluate the function of circ_0086296 in vivo. circ_0086296 expression was significantly upregulated in human carotid artery plaques, oxidized low-density lipoprotein (ox-LDL)-treated HUVECs, and the aorta of atherosclerotic mice. Functional analysis indicated that circ_0086296 promotes ECs injury in vitro and atherosclerosis progression in vivo. The mechanism analysis indicated that circ_0086296 sponged miR-576-3p to promote IFIT1–STAT1 expression. Moreover, STAT1 upregulated circ_0086296 expression, forming the circ_0086296/miR-576-3p/IFIT1/STAT1 feedback loop. Notably, inhibition of the circ_0086296/miR-576-3p/IFIT1 axis could block atherosclerotic lesion formation both in vivo and in vitro. Finally, circ_0086296 was overexpressed in exosomes of patients with atherosclerosis and exosomes of ox-LDL-treated ECs. Therefore, the circ_0086296/miR-576-3p/IFIT1/STAT1 feedback loop participates in atherosclerosis progression and contributes to the high circ_0086296 expression observed in the exosomes of serum of patients with atherosclerosis. This study sought to provide a deep understanding of the mechanisms underlying the aberrant EC phenotype in AS.

Knockdown of lncRNA H19 alleviates ox-LDL-induced HCAECs inflammation and injury by mediating miR-20a-5p/HDAC4 axis

BACKGROUND

Coronary artery disease (CAD) seriously disturbs the life of people. LncRNA H19 is reported to promote the progression of CAD; Nevertheless, the detailed mechanism by which H19 modulates CAD development is unclear.

METHODS

Clinical samples of CAD patients were collected, meanwhile we established in vitro and in vivo models of CAD by treating HCAECs with ox-LDL and feeding ApoE^-/- mice with high fat diets (HFD). MTT assay was adopted to assess the cell viability. Transwell detection was applied to test the migration, and apoptosis was tested by flow cytometry. The levels of inflammatory cytokines were examined by ELISA. The relation among H19, miR-20a-5p and HDAC4 was explored by dual luciferase reporter and RIP assay.

RESULTS

H19 and HDAC4 levels were elevated, while miR-20a-5p was reduced in plasma of CAD patients and ox-LDL-treated HCAECs. ox-LDL increased H19 level and induced apoptosis and inflammation in HCAECs, while silencing of H19 rescued this phenomenon. In addition, the level of H19 was negatively correlated with miR-20a-5p, and miR-20a-5p inhibitor restored the effect of H19 silencing on HCAECs function. HDAC4 was the downstream mRNA of miR-20a-5p, and miR-20a-5p upregulation reversed ox-LDL-induced HCAECs injury through targeting HDAC4. Furthermore, H19 silencing significantly alleviated the coronary atherosclerotic plaques and inhibited the inflammatory responses in vivo.

CONCLUSIONS

We proved that knockdown of H19 alleviated ox-LDL-induced HCAECs injury via miR-20a-5p/HDAC4 axis, which might provide a new tactics against CAD.

The mechanisms of glycolipid metabolism disorder on vascular injury in type 2 diabetes

Patients with diabetes have severe vascular complications, such as diabetic nephropathy, diabetic retinopathy, cardiovascular disease, and neuropathy. Devastating vascular complications lead to increased mortality, blindness, kidney failure, and decreased overall quality of life in people with type 2 diabetes (T2D). Glycolipid metabolism disorder plays a vital role in the vascular complications of T2D. However, the specific mechanism of action remains to be elucidated. In T2D patients, vascular damage begins to develop before insulin resistance and clinical diagnosis. Endothelial dysregulation is a significant cause of vascular complications and the early event of vascular injury. Hyperglycemia and hyperlipidemia can trigger inflammation and oxidative stress, which impair endothelial function. Furthermore, during the pathogenesis of T2D, epigenetic modifications are aberrant and activate various biological processes, resulting in endothelial dysregulation. In the present review, we provide an overview and discussion of the roles of hyperglycemia- and hyperlipidemia-induced endothelial dysfunction, inflammatory response, oxidative stress, and epigenetic modification in the pathogenesis of T2D. Understanding the connections of glucotoxicity and lipotoxicity with vascular injury may reveal a novel potential therapeutic target for diabetic vascular complications.

Cardiomyocyte death in sepsis: Mechanisms and regulation (Review)

Sepsis‑induced cardiac dysfunction is one of the most common types of organ dysfunction in sepsis; its pathogenesis is highly complex and not yet fully understood. Cardiomyocytes serve a key role in the pathophysiology of cardiac function; due to the limited ability of cardiomyocytes to regenerate, their loss contributes to decreased cardiac function. The activation of inflammatory signalling pathways affects cardiomyocyte function and modes of cardiomyocyte death in sepsis. Prevention of cardiomyocyte death is an important therapeutic strategy for sepsis‑induced cardiac dysfunction. Thus, understanding the signalling pathways that activate cardiomyocyte death and cross‑regulation between death modes are key to finding therapeutic targets. The present review focused on advances in understanding of sepsis‑induced cardiomyocyte death pathways, including apoptosis, necroptosis, mitochondria‑mediated necrosis, pyroptosis, ferroptosis and autophagy. The present review summarizes the effect of inflammatory activation on cardiomyocyte death mechanisms, the diversity of regulatory mechanisms and cross‑regulation between death modes and the effect on cardiac function in sepsis to provide a theoretical basis for treatment of sepsis‑induced cardiac dysfunction.

Noncoding RNA-mediated macrophage and cancer cell crosstalk in hepatocellular carcinoma

The tumor microenvironment (TME) is a well-recognized system that plays an essential role in tumor initiation, development, and progression. Intense intercellular communication between tumor cells and other cells (especially macrophages) occurs in the TME and is mediated by cell-to-cell contact and/or soluble messengers. Emerging evidence indicates that noncoding RNAs (ncRNAs) are critical regulators of the relationship between cells within the TME. In this review, we provide an update on the regulation of ncRNAs (primarily micro RNAs [miRNAs], long ncRNAs [lncRNAs], and circular RNAs [circRNAs]) in the crosstalk between macrophages and tumor cells in hepatocellular carcinoma (HCC). These ncRNAs are derived from macrophages or tumor cells and act as oncogenes or tumor suppressors, contributing to tumor progression not only by regulating the physiological and pathological processes of tumor cells but also by controlling macrophage infiltration, activation, polarization, and function. Herein, we also explore the options available for clinical therapeutic strategies targeting crosstalk-related ncRNAs to treat HCC. A better understanding of the relationship between macrophages and tumor cells mediated by ncRNAs will uncover new diagnostic biomarkers and pharmacological targets in cancer.

miR-145-5p affects autophagy by targeting CaMKIIδ in atherosclerosis

BACKGROUND

Atherosclerosis (AS) is a chronic progressive inflammatory disease involving many cells. miR-145-5p mediates the biological phenotypes of human aortic vascular smooth muscle cells (HAVSMCs) and influences the progression of AS, but the potential mechanism needs further study.

METHODS

Total RNA was extracted from patient plasma and arteries to determine the expression of miR-145-5p. The CaMKIIδ pathway and genes were predicted as the target of miR-145-5p by bioinformatics approaches. The interaction between miR-145-5p and CaMKIIδ was confirmed by RT-qPCR and Dual Luciferase Reporter Assay System. Western blot analysis, immunofluorescence staining, transmission electron microscopy (TEM) and protein tracing on HAVSMCs transduced with mCherry-GFP-LC3 lentiviral vectors to determine the mechanism by which miR-145-5p affects the atherosclerotic disease process.

RESULTS

The expression of miR-145-5p was downregulated in blood and arteries specimens of patients with coronary stenosis. Correspondingly, CaMKIIδ was upregulated and miR-145-5p was downregulated in hypoxic HAVSMCs. CaMKIIδ was predicted and confirmed as a downstream target of miR-145-5p. In addition, CaMKIIδ induced the upregulation of autophagy-related proteins by activating the AMPK/mTOR/ULK1 signalling pathway. Moreover, we confirmed that miR-145-5p inhibits CaMKIIδ expression by binding to a specific sequence in the CaMKIIδ 3' UTR and affects autophagy. Crucially, CaMKIIδ was promoted by the downregulation of miR-145-5p and then activating autophagy in HAVSMCs through the AMPK/mTOR/ULK1 signalling pathway to affect the AS progress.

CONCLUSIONS

miR-145-5p regulates CaMKIIδ, leading to altered autophagy in HAVSMCs. This alteration plays an important role in AS progression.

High expression of SETDB1 mediated by miR-29a-3p associates with poor prognosis and immune invasion in breast invasive carcinoma

Background

Breast invasive carcinoma (BRCA) has a poor prognosis. Numerous studies have shown that SET domain bifurcated histone lysine methyltransferase 1 (SETDB1) is involved in the initiation and progression of many cancers. This study aims to reveal the potential mechanism of SETDB1 in the development and progression of BRCA.

Methods

The ONCOMINE database, TIMER database, UALCAN database and GEPIA database were used to analyze the expression of SETDB1 in human cancers. We evaluated the expression level of SETDB1 in cell lines by quantitative real-time polymerase chain reaction (qPCR), and the survival analysis of SETDB1 was performed on PrognoScan and Kaplan-Meier plotter websites. The upstream regulator was obtained from starBase database.

Results

We confirmed that SETDB1 messenger RNA (mRNA) level showed high expression in breast cell lines, and we also found that SETDB1 showed high expression in many types of cancers. Moreover, SETDB1 overexpression was positively correlated with poor prognosis in BRCA. Furthermore, we first predicted miR-29a-3p was a potential upstream regulator of SETDB1 in BRCA. Our findings indicated that SETDB1 might play a carcinogenic role by increasing the infiltration of immune cell and influencing immune checkpoint expression.

Conclusions

This study suggested that miR-29a-3p can mediate the expression of SETDB1 with poor prognosis and tumor immune infiltration in BRCA.

circRNA is a potential target for cardiovascular diseases treatment

Circular RNAs (circRNAs), a novel class of endogenous noncoding RNA, are characterized by their covalently closed-loop structures without a 5' cap or a 3' poly(A) tail. With the evolution of high-throughput sequencing technology and bioinformatics, an increasing number of circRNAs have been discovered, and their functions were highlighted. Cardiovascular diseases (CVDs) have become the world's leading killers, with serious impacts on human health. Although significant progress has been made in clarifying the development of CVDs from the molecular to the cellular level, CVDs remain one of the leading causes of death in humans. circRNAs mainly function as a "sponge" to absorb microRNAs, which results in the positive control of downstream proteins. They play important regulatory roles in the development of CVDs. This paper reviews current knowledge on the biogenesis, detection and validation, translation, translocation and degradation, and general functions of circRNAs, with a focus on their roles in CVDs.

Emerging roles of circRNAs in the pathological process of myocardial infarction

Myocardial infarction (MI) is defined as cardiomyocyte death in a clinical context consistent with ischemic insult. MI remains one of the leading causes of morbidity and mortality worldwide. Although there are a number of effective clinical methods for the diagnosis and treatment of MI, further investigation of novel biomarkers and molecular therapeutic targets is required. Circular RNAs (circRNAs), novel non-coding RNAs, have been reported to function mainly by acting as microRNA (miRNA) sponges or binding to RNA-binding proteins (RBPs). The circRNA-miRNA-mRNA (protein) regulatory pathway regulates gene expression and affects the pathological mechanisms of various diseases. Undoubtedly, a more comprehensive understanding of the relationship between MI and circRNA will lay the foundation for the development of circRNA-based diagnostic and therapeutic strategies for MI. Therefore, this review summarizes the pathophysiological process of MI and various approaches to measure circRNA levels in MI patients, tissues, and cells; highlights the significance of circRNAs in the regulation MI pathogenesis and development; and provides potential clinical insight for the diagnosis, prognosis, and treatment of MI.

LncRNA SNHG20 promotes migration and invasion of ovarian cancer via modulating the microRNA-148a/ROCK1 axis

BACKGROUND

Ovarian cancer (OC) is characterized by early metastasis and poor prognosis, which threatens the health of women worldwide. Small nucleolar RNA host gene 20 (SNHG20), a long noncoding RNA (lncRNA), has been verified to be significantly up-regulated in several tumors, including OC. MicroRNA-148a (miR-148a)/rho-kinase1 (ROCK1) axis plays an important role in the modulation of tumor development. However, whether SNHG20 can regulate OC progression through miR-148a/ROCK1 axis remains unclear. Normal human ovarian epithelial cell line and four OC cell lines were adopted for in vitro experiments. Real-time PCR was performed to assess the levels of SNHG20 and miR-148a. OC cell proliferation, apoptosis, invasion and migration were detected using clone formation, flow cytometry, transwell, and wound healing assays, respectively. Tumor xenograft assay was applied to evaluate the effect of SNHG20 on tumor growth in vivo.

RESULTS

Significant higher expression of SNHG20 was observed in OC cell lines. SNHG20 markedly promoted the invasion, migration, proliferation and inhibited the apoptosis of OC cells. SNHG20 enhanced ROCK1 expression by sponging miR-148a, and the direct binding between SNHG20/ROCK1 and miR-148a was identified.

CONCLUSION

SNHG20 promoted invasion and migration of OC via targeting miR-148a/ROCK1 axis. The present research may provide a novel insight for the therapeutic strategies of OC.

Over Fifty Years of Life, Death, and Cannibalism: A Historical Recollection of Apoptosis and Autophagy

Research in biomedical sciences has changed dramatically over the past fifty years. There is no doubt that the discovery of apoptosis and autophagy as two highly synchronized and regulated mechanisms in cellular homeostasis are among the most important discoveries in these decades. Along with the advancement in molecular biology, identifying the genetic players in apoptosis and autophagy has shed light on our understanding of their function in physiological and pathological conditions. In this review, we first describe the history of key discoveries in apoptosis with a molecular insight and continue with apoptosis pathways and their regulation. We touch upon the role of apoptosis in human health and its malfunction in several diseases. We discuss the path to the morphological and molecular discovery of autophagy. Moreover, we dive deep into the precise regulation of autophagy and recent findings from basic research to clinical applications of autophagy modulation in human health and illnesses and the available therapies for many diseases caused by impaired autophagy. We conclude with the exciting crosstalk between apoptosis and autophagy, from the early discoveries to recent findings.

The critical role of epigenetic mechanism in PM2.5-induced cardiovascular diseases

Cardiovascular disease (CVD) has become the leading cause of death worldwide, which seriously threatens human life and health. Epidemiological studies have confirmed the occurrence and development of CVD are closely related to air pollution. In particular, fine particulate matter (PM_2.5) is recognized as an important environmental factor contributing to increased morbidity, mortality and hospitalization rates among adults and children. However, the underlying mechanism by which PM_2.5 promotes CVD development remains unclear. With the development of epigenetics, recent studies have shown that PM_2.5 exposure may induce or aggravate CVD through epigenetic changes. In order to better understand the potential mechanisms, this paper reviews the epigenetic changes of CVD caused by PM_2.5. We summarized the epigenetic mechanisms of PM_2.5 causing cardiovascular pathological damage and functional changes, mainly involving DNA methylation, non-coding RNA, histone modification and chromosome remodeling. It will provide important clues for exploring the biological mechanisms affecting cardiovascular health.

The regulatory roles of aminoacyl-tRNA synthetase in cardiovascular disease

Aminoacyl-tRNA synthetases (ARSs) are widely found in organisms, which can activate amino acids and make them bind to tRNA through ester bond to form the corresponding aminoyl-tRNA. The classic function of ARS is to provide raw materials for protein biosynthesis. Recently, emerging evidence demonstrates that ARSs play critical roles in controlling inflammation, immune responses, and tumorigenesis as well as other important physiological and pathological processes. With the recent development of genome and exon sequencing technology, as well as the discovery of new clinical cases, ARSs have been reported to be closely associated with a variety of cardiovascular diseases (CVDs), particularly angiogenesis and cardiomyopathy. Intriguingly, aminoacylation was newly identified and reported to modify substrate proteins, thereby regulating protein activity and functions. Sensing the availability of intracellular amino acids is closely related to the regulation of a variety of cell physiology. In this review, we summarize the research progress on the mechanism of CVDs caused by abnormal ARS function and introduce the clinical phenotypes and characteristics of CVDs related to ARS dysfunction. We also highlight the potential roles of aminoacylation in CVDs. Finally, we discuss some of the limitations and challenges of present research. The current findings suggest the significant roles of ARSs involved in the progress of CVDs, which present the potential clinical values as novel diagnostic and therapeutic targets in CVD treatment.

Regulation of pyroptosis in cardiovascular pathologies: Role of noncoding RNAs

Cardiovascular disease (CVD) is one of the most important diseases endangering human life. The pathogenesis of CVDs is complex. Pyroptosis, which differs from traditional apoptosis and necrosis, is characterized by cell swelling until membrane rupture, resulting in the release of cell contents and activation of a strong inflammatory response. Recent studies have revealed that inflammation and pyroptosis play important roles in the progression of CVDs. Noncoding RNAs (ncRNAs) are considered promising biomarkers and potential therapeutic targets for the diagnosis and treatment of various diseases, including CVDs. Growing evidence has revealed that ncRNAs can mediate the transcriptional or posttranscriptional regulation of pyroptosis-related genes by participating in the pyroptosis regulatory network. The role and molecular mechanism of pyroptosis-regulating ncRNAs in cardiovascular pathologies are attracting increasing attention. Here, we summarize research progress on pyroptosis and the role of ncRNAs, particularly microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs), in the regulation of pyroptosis in CVD pathologies. Identifying these disease-related ncRNAs is important for understanding the pathogenesis of CVDs and providing new targets and ideas for their prevention and treatment.

Epigenetic Regulation of Autophagy in Cardiovascular Pathobiology

Cardiovascular diseases (CVDs) are the number one cause of debilitation and mortality worldwide, with a need for cost-effective therapeutics. Autophagy is a highly conserved catabolic recycling pathway triggered by various intra- or extracellular stimuli to play an essential role in development and pathologies, including CVDs. Accordingly, there is great interest in identifying mechanisms that govern autophagic regulation. Autophagic regulation is very complex and multifactorial that includes epigenetic pathways, such as histone modifications to regulate autophagy-related gene expression, decapping-associated mRNA degradation, microRNAs, and long non-coding RNAs; pathways are also known to play roles in CVDs. Molecular understanding of epigenetic-based pathways involved in autophagy and CVDs not only will enhance the understanding of CVDs, but may also provide novel therapeutic targets and biomarkers for CVDs.

Circular RNAs act as regulators of autophagy in cancer

Circular RNAs (circRNAs) are a large class of noncoding RNAs that are emerging as critical regulators of various cellular processes that are involved in the physiopathological mechanism of many human diseases, such as cardiovascular disease, atherosclerosis, diabetes mellitus, and carcinogenesis. Autophagy is a conserved and catabolic cellular process that degrades unfolded, misfolded, or damaged protein aggregates or organelles to maintain cellular homeostasis under physiological and pathological conditions. Increasing evidence has shown a link between circRNAs and autophagy that is closely related to the occurrence and development of human diseases, including cancer. In this review, we highlight recent advances in understanding the functions and mechanisms of circRNAs in the regulation of autophagy in cancer. These autophagy-related circRNAs contribute to cancer development and progression in various types of human cancer by activating or inhibiting autophagy. Cumulative research on the relationship between circRNAs and autophagy regulation provides critical insight into the essential role that circRNAs play in carcinogenesis and suggests new targets for tumor therapy.

Relationship between long non-coding RNA polymorphism and the risk of coronary artery disease: A protocol for systematic review and meta-analysis

BACKGROUND

Previous epidemiological studies displayed that long non-coding RNA (LncRNA) polymorphisms are associated with an increased risk of coronary artery disease, while the results are inconsistent. Therefore, we conducted a meta-analysis to more accurately determine the association between LncRNA polymorphism and the risk of coronary artery disease.

METHODS

PubMed, EmBase and Web of Science databases were searched, and the time to build the database was set until December 2020. The association between LncRNA polymorphism and the risk of coronary artery disease was collected and evaluated. Meta-analysis was performed by STATA 14.0 software, and the odds ratio and its 95% confidence interval (95%CI) were applied to estimate the association between LncRNA polymorphism and the risk of coronary artery disease.

RESULTS

The results of this meta-analysis will be submitted to a peer-reviewed journal for publication.

CONCLUSION

This meta-analysis will summarize the relationship between LncRNA polymorphism and coronary disease risk.

ETHICS AND DISSEMINATION

Ethical approval was not required for this study. The systematic review will be published in a peer-reviewed journal, presented at conferences, and shared on social media platforms. This review would be disseminated in a peer-reviewed journal or conference presentations.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/9XPHS.