HOTAIR functions as a competing endogenous RNA to regulate PTEN expression by inhibiting miR-19 in cardiac hypertrophy

Long non-coding RNAs in cardiac hypertrophy and heart failure: functions, mechanisms and clinical prospects

The surge in reports describing non-coding RNAs (ncRNAs) has focused attention on their possible biological roles and effects on development and disease. ncRNAs have been touted as previously uncharacterized regulators of gene expression and cellular processes, possibly working to fine-tune these functions. The sheer number of ncRNAs identified has outpaced the capacity to characterize each molecule thoroughly and to reliably establish its clinical relevance; it has, nonetheless, created excitement about their potential as molecular targets for novel therapeutic approaches to treat human disease. In this Review, we focus on one category of ncRNAs - long non-coding RNAs - and their expression, functions and molecular mechanisms in cardiac hypertrophy and heart failure. We further discuss the prospects for this specific class of ncRNAs as novel targets for the diagnosis and treatment of these conditions.

Emerging roles of HOTAIR lncRNA in the pathogenesis and prognosis of cardiovascular diseases

Highlights HOTAIR, a long noncoding RNA, plays a role in the regulation of proteins involved in the pathogenesis of cardiovascular disease. Furthermore, it has been identified as a biomarker of this type of disease. Several factors and cells contribute to atherosclerosis, a progressive disease. However, the prognosis of HOTAIR in this disease varies depending on the path in which it plays a role. For this condition, there is no single prognosis to consider.

Getting to know ovarian cancer: Focusing on the effect of LncRNAs in this cancer and the effective signaling pathways

This article undertakes a comprehensive investigation of ovarian cancer, examining the complex nature of this challenging disease. The main focus is on understanding the role of long non-coding RNAs (lncRNAs) in the context of ovarian cancer (OC), and their regulatory functions in disease progression. Through extensive research, the article identifies specific lncRNAs that play significant roles in the intricate molecular processes of OC. Furthermore, the study examines the signaling pathways involved in the development of OC, providing a detailed comprehension of the underlying molecular mechanisms. By connecting lncRNA dynamics with signaling pathways, this exploration not only advances our understanding of ovarian cancer but also reveals potential targets for therapeutic interventions. The findings open up opportunities for targeted treatments, highlighting the importance of personalized approaches in addressing this complex disease and driving progress in ovarian cancer research and treatment strategies.

Genetics and epigenetics of diabetes and its complications in India

Diabetes mellitus (DM) has become a significant health concern with an increasing rate of morbidity and mortality worldwide. India ranks second in the number of diabetes cases in the world. The increasing burden of DM can be explained by genetic predisposition of Indians to type 2 diabetes mellitus (T2DM) coupled with rapid urbanization and socio-economic development in the last 3 decades leading to drastic changes in lifestyle. Environment and lifestyle changes contribute to T2DM development by altering epigenetic processes such as DNA methylation, histone post-translational modifications, and long non-coding RNAs, all of which regulate chromatin structure and gene expression. Although the genetic predisposition of Indians to T2DM is well established, how environmental and genetic factors interact and lead to T2DM is not well understood. In this review, we discuss the prevalence of diabetes and its complications across different states in India and how various risk factors contribute to its pathogenesis. The review also highlights the role of genetic predisposition among the Indian population and epigenetic factors involved in the etiology of diabetes. Lastly, we review current treatments and emphasize the knowledge gap with respect to genetic and epigenetic factors in the Indian context. Further understanding of the genetic and epigenetic determinants will help in risk prediction and prevention as well as therapeutic interventions, which will improve the clinical management of diabetes and associated macro- and micro-vascular complications.

Mechanism of lncRNA HOTAIR in attenuating cardiomyocyte pyroptosis in mice with heart failure via the miR-17-5p/RORA axis

Heart failure (HF) is a complex clinical syndrome associated with significant morbidity and mortality. Dysregulation of long non-coding RNA (lncRNA) has been implicated in the pathogenesis of HF. The present study aims to investigate the role of lncRNA HOX transcript antisense RNA (HOTAIR) in cardiomyocyte pyroptosis in a murine HF model. A murine HF model was established through transverse aortic contraction surgery, and an in vitro HF cell model was developed by treating HL-1 cells with H2O2. HOTAIR was overexpressed in TAC mice and HL-1 cells via pcDNA3.1-HOTAIR transfection. Cardiac function was assessed in TAC mice, and myocardial changes were evaluated using HE staining. The expression of NLRP3 was examined by immunohistochemistry. Myocardial injury markers and pyroptosis-related inflammatory cytokines were quantified using ELISA. Protein levels of NLRP3, cleaved-caspase-1, and GSDMD-N were analyzed by Western blot. Dual-luciferase assays and RNA immunoprecipitation were employed to confirm the binding interactions between HOTAIR and miR-17-5p, miR-17-5p and RORA. Functional rescue experiments were conducted by overexpressing miR-17-5p or silencing RORA in HL-1 cells. HOTAIR exhibited reduced expression in TAC mice and H2O2-induced cardiomyocytes. Overexpression of HOTAIR ameliorated cardiac dysfunction, reduced myocardial pathological injury, enhanced cardiomyocyte viability, and decreased myocardial injury and pyroptosis. HOTAIR interacted with miR-17-5p to repress RORA transcription. Overexpression of miR-17-5p or silencing of RORA abolished the inhibitory effect of HOTAIR overexpression on cardiomyocyte pyroptosis. In conclusion, HOTAIR competitively bound to miR-17-5p, relieving its inhibition of RORA transcription and leading to increased RORA expression and suppressed cardiomyocyte pyroptosis in HF models.

LOC102549726/miR-760-3p network is involved in the progression of ISO-induced pathological cardiomyocyte hypertrophy via endoplasmic reticulum stress

Pathological cardiac hypertrophy (CH) is featured by myocyte enlargement and cardiac malfunction. Multiple signaling pathways have been implicated in diverse pathological and physiological processes in CH. However, the function of LOC102549726/miR-760-3p network in CH remains unclear. Here, we characterize the functional role of LOC102549726/miR-760-3p network in CH and delineate the underlying mechanism. The expression of LncRNA LOC102549726 and hypertrophic markers was significantly increased compared to the control, while the level of miR-760-3p was decreased. Next, we examined ER stress response in a hypertrophic cardiomyocyte model. The expression of ER stress markers was greatly enhanced after incubation with ISO. The hypertrophic reaction, ER stress response, and increased potassium and calcium ion channels were alleviated by genetic downregulation of LOC102549726. It has been demonstrated that LOC102549726 functions as a competitive endogenous RNA (ceRNA) of miR-760-3p. Overexpression of miR-760-3p decreased cell surface area and substantially mitigated ER stress response; protein levels of potassium and calcium channels were also significantly up-regulated compared to the NC control. In contrast, miR-760-3p inhibition increased cell size, aggravated CH and ER stress responses, and reduced ion channels. Collectively, in this study we demonstrated that the LOC102549726/miR-760-3p network was a crucial regulator of CH development. Ion channels mediate the ER stress response and may be a downstream sensor of the LOC102549726/miR-760-3p network. Therefore, these findings advance our understanding of pathological CH and provide new insights into therapeutic targets for cardiac remodeling.

The role and medical prospects of long non-coding RNAs in cardiovascular disease

Cardiovascular disease (CVD) has reached epidemic proportions and is a leading cause of death worldwide. One of the long-standing goals of scientists is to repair heart tissue damaged by various forms of CVD such as cardiac hypertrophy, dilated cardiomyopathy, myocardial infarction, heart fibrosis, and genetic and developmental heart defects such as heart valve deformities. Damaged or defective heart tissue has limited regenerative capacity and results in a loss of functioning myocardium. Advances in transcriptomic profiling technology have revealed that long noncoding RNA (lncRNA) is transcribed from what was once considered "junk DNA." It has since been discovered that lncRNAs play a critical role in the pathogenesis of various CVDs and in myocardial regeneration. This review will explore how lncRNAs impact various forms of CVD as well as those involved in cardiomyocyte regeneration. Further, we discuss the potential of lncRNAs as a therapeutic modality for treating CVD.

Apoptosis and long non-coding RNAs: Focus on their roles in Heart diseases

Heart disease is one of the principal death reasons around the world and there is a growing requirement to discover novel healing targets that have the potential to avert or manage these illnesses. On the other hand, apoptosis is a strongly controlled, cell removal procedure that has a crucial part in numerous cardiac problems, such as reperfusion injury, MI (myocardial infarction), consecutive heart failure, and inflammation of myocardium. Completely comprehending the managing procedures of cell death signaling is critical as it is the primary factor that influences patient mortality and morbidity, owing to cardiomyocyte damage. Indeed, the prevention of heart cell death appears to be a viable treatment approach for heart illnesses. According to current researches, a number of long non-coding RNAs cause the heart cells death via different methods that are embroiled in controlling the activity of transcription elements, the pathways that signals transmission within cells, small miRNAs, and the constancy of proteins. When there is too much cell death in the heart, it can cause problems like reduced blood flow, heart damage after restoring blood flow, heart disease in diabetics, and changes in the heart after reduced blood flow. Therefore, studying how lncRNAs control apoptosis could help us find new treatments for heart diseases. In this review, we present recent discoveries about how lncRNAs are involved in causing cell death in different cardiovascular diseases.

The regulation of PTEN: Novel insights into functions as cancer biomarkers and therapeutic targets

This review summarizes the implications of the primary tumor suppressor protein phosphatase and tensin homolog (PTEN) in aggressive cancer development. PTEN interacts with other cellular proteins or factors suggesting the existence of an intricate molecular network that regulates their oncogenic function. Accumulating evidence has shown that PTEN exists and plays a role in the cytoplasmic organelles and in the nucleus. PTEN blocks phosphoinositide 3-kinases (PI3K)-protein kinase B-mammalian target of rapamycin signaling pathway by dephosphorylating phosphatidylinositol (PI)-3,4,5-triphosphate to PI-4,5-bisphosphate thus counteracting PI3K function. Studies have shown that PTEN expression is tightly regulated at transcriptional, posttranscriptional, and posttranslational levels (including protein-protein interactions and posttranslational modifications). Despite recent advances in PTEN research, the regulation and function of the PTEN gene remain largely unknown. How mutation or loss of specific exons in the PTEN gene occurs and involves in cancer development is not clear. This review illustrates the regulatory mechanisms of PTEN expression and discusses how PTEN participates in tumor development and/or suppression. Future prospects for the clinical applications are also highlighted.

The Function and Therapeutic Potential of lncRNAs in Cardiac Fibrosis

Cardiac fibrosis remains an unresolved problem in cardiovascular diseases. Fibrosis of the myocardium plays a key role in the clinical outcomes of patients with heart injuries. Moderate fibrosis is favorable for cardiac structure maintaining and contractile force transmission, whereas adverse fibrosis generally progresses to ventricular remodeling and cardiac systolic or diastolic dysfunction. The molecular mechanisms involved in these processes are multifactorial and complex. Several molecular mechanisms, such as TGF-β signaling pathway, extracellular matrix (ECM) synthesis and degradation, and non-coding RNAs, positively or negatively regulate myocardial fibrosis. Long noncoding RNAs (lncRNAs) have emerged as significant mediators in gene regulation in cardiovascular diseases. Recent studies have demonstrated that lncRNAs are crucial in genetic programming and gene expression during myocardial fibrosis. We summarize the function of lncRNAs in cardiac fibrosis and their contributions to miRNA expression, TGF-β signaling, and ECMs synthesis, with a particular attention on the exosome-derived lncRNAs in the regulation of adverse fibrosis as well as the mode of action of lncRNAs secreted into exosomes. We also discuss how the current knowledge on lncRNAs can be applied to develop novel therapeutic strategies to prevent or reverse cardiac fibrosis.

Comparative Analysis of Non-Coding RNA Transcriptomics in Heart Failure

Heart failure constitutes a clinical complex syndrome with different symptomatic characteristics depending on age, sex, race and ethnicity, among others, which has become a major public health issue with an increasing prevalence. One of the most interesting tools seeking to improve prevention, diagnosis, treatment and prognosis of this pathology has focused on finding new molecular biomarkers since heart failure relies on deficient cardiac homeostasis, which is regulated by a strict gene expression. Therefore, currently, analyses of non-coding RNA transcriptomics have been oriented towards human samples. The present review develops a comparative study emphasizing the relevance of microRNAs, long non-coding RNAs and circular RNAs as potential biomarkers in heart failure. Significantly, further studies in this field of research are fundamental to supporting their widespread clinical use. In this sense, the various methodologies used by the authors should be standardized, including larger cohorts, homogeneity of the samples and uniformity of the bioinformatic pipelines used to reach stratification and statistical significance of the results. These basic adjustments could provide promising steps to designing novel strategies for clinical management of patients with heart failure.

Identification of a long noncoding RNA Gm17501 as a novel negative regulator of cardiac hypertrophy

Pathological cardiac hypertrophy is an independent risk factor for the development of heart failure. Long noncoding RNAs (lncRNAs), an emerging class of non-protein-coding transcripts, are involved in regulation of multiple cardiac diseases through diverse molecular mechanism, whereas the role of cytoplasmic lncRNAs in regulating cardiac hypertrophy remains unclear. In this study, we identified a novel and functional long noncoding RNA Gm17501, which was predominantly expressed in the cytoplasm of cardiomyocytes. The expression level of lncRNA Gm17501 was altered in cardiac hypertrophy induced by pressure overload and phenylephrine treatment. Moreover, lncRNA Gm17501 expression was decreased in the heart tissue of patients with heart failure. Silencing lncRNA Gm17501 aggravated cardiac hypertrophy under pathological stress. Inhibition of lncRNA Gm17501 did not alter the expression of nearby genes but decreased mRNA level of calcium handling proteins which were involved in cardiac contraction. Therefore, the cytoplasmic lncRNA Gm17501 might protect cardiomyocytes against hypertrophy, possibly by maintaining calcium signaling pathway.

Downregulation of lncRNA MALAT1 Inhibits Angiotensin II-induced Hypertrophic Effects of Cardiomyocytes by Regulating SIRT4 via miR-93-5p

Cardiac hypertrophy is a leading risk for heart failure and sudden death. Long non-coding RNAs (lncRNAs) have been implicated in a variety of human diseases, including cardiac hypertrophy. We aimed to investigate the potential role and functional mechanism of lncRNA metastasis-associated in lung adenocarcinoma transcript 1 (MALAT1) in cardiac hypertrophy. C57BL/6 mice underwent transverse aortic constriction (TAC) to induce cardiac hypertrophy in vivo. The expression of MALAT1, miR-93-5p, and sirtuin 4 (SIRT4) mRNA was detected using a quantitative real-time polymerase chain reaction. The protein levels of cardiac hypertrophy-related markers, including atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP) and β-myosin heavy chain (β-MHC), and SIRT4 were measured via western blotting. The putative interaction between miR-93-5p and MALAT1 or SIRT4 was verified using a dual-luciferase reporter assay, RNA immunoprecipitation assay, or pull-down assay. Consequently, the expression of MALAT1 and SIRT4 was increased in TAC-treated mouse heart and angiotensin II (Ang-II)-induced cardiomyocytes, whereas the expression of miR-93-5p was decreased. Ang-II promoted the expression of ANP, BNP, and β-MHC and the surface area of cardiomyocytes, whereas MALAT1 downregulation impaired their expression and cell area. MiR-93-5p was a target of MALAT1, and its inhibition reversed the effects of MALAT1 downregulation. More importantly, MALAT1 modulated SIRT4 expression by degrading miR-93-5p. The expression of ANP, BNP, and β-MHC suppressed by miR-93-5p restoration was recovered by SIRT4 promotion. Overall, MALAT1 knockdown ameliorated cardiac hypertrophy partly by regulating the miR-93-5p/SIRT4 network, indicating that MALAT1 was a substantial indicator of cardiac hypertrophy.

Long Non-Coding RNAs in Cardiac Hypertrophy

Heart disease represents one of the main challenges in modern medicine with insufficient treatment options. Whole genome sequencing allowed for the discovery of several classes of non-coding RNA (ncRNA) and widened our understanding of disease regulatory circuits. The intrinsic ability of long ncRNAs (lncRNAs) and circular RNAs (circRNAs) to regulate gene expression by a plethora of mechanisms make them candidates for conceptually new treatment options. However, important questions remain to be addressed before we can fully exploit the therapeutic potential of these molecules. Increasing our knowledge of their mechanisms of action and refining the approaches for modulating lncRNAs expression are just a few of the challenges we face. The accurate identification of novel lncRNAs is hampered by their relatively poor cross-species sequence conservation and their low and context-dependent expression pattern. Nevertheless, progress has been made in their annotation in recent years, while a few experimental studies have confirmed the value of lncRNAs as new mechanisms in the development of cardiac hypertrophy and other cardiovascular diseases. Here, we explore cardiac lncRNA biology and the evidence that this class of molecules has therapeutic benefit to treat cardiac hypertrophy.

Non-Coding RNAs: Prevention, Diagnosis, and Treatment in Myocardial Ischemia-Reperfusion Injury

Recent knowledge concerning the role of non-coding RNAs (ncRNAs) in myocardial ischemia/reperfusion (I/R) injury provides new insight into their possible roles as specific biomarkers for early diagnosis, prognosis, and treatment. MicroRNAs (miRNAs) have fewer than 200 nucleotides, while long ncRNAs (lncRNAs) have more than 200 nucleotides. The three types of ncRNAs (miRNAs, lncRNAs, and circRNAs) act as signaling molecules strongly involved in cardiovascular disorders (CVD). I/R injury of the heart is the main CVD correlated with acute myocardial infarction (AMI), cardiac surgery, and transplantation. The expression levels of many ncRNAs and miRNAs are highly modified in the plasma of MI patients, and thus they have the potential to diagnose and treat MI. Cardiomyocyte and endothelial cell death is the major trigger for myocardial ischemia–reperfusion syndrome (MIRS). The cardioprotective effect of inflammasome activation in MIRS and the therapeutics targeting the reparative response could prevent progressive post-infarction heart failure. Moreover, the pharmacological and genetic modulation of these ncRNAs has the therapeutic potential to improve clinical outcomes in AMI patients.

The Role of Epigenetic Mechanisms in Autoimmune, Neurodegenerative, Cardiovascular, and Imprinting Disorders

Epigenetic mutations like aberrant DNA methylation, histone modifications, or RNA silencing are found in a number of human diseases. This review article discusses the epigenetic mechanisms involved in neurodegenerative disorders, cardiovascular disorders, auto-immune disorder, and genomic imprinting disorders. In addition, emerging epigenetic therapeutic strategies for the treatment of such disorders are presented. Medicinal chemistry campaigns highlighting the efforts of the chemists invested towards the rational design of small molecule inhibitors have also been included. Pleasingly, several classes of epigenetic inhibitors, DNMT, HDAC, BET, HAT, and HMT inhibitors along with RNA based therapies have exhibited the potential to emerge as therapeutics in the longer run. It is quite hopeful that epigenetic modulator-based therapies will advance to clinical stage investigations by leaps and bounds.

lncRNA ROR and miR-125b Predict the Prognosis in Heart Failure Combined Acute Renal Failure

Objective

To elucidate the correlation between expression levels of long noncoding RNA (lncRNA) ROR and microRNA-125b (miR-125b) with the prognosis in heart failure (HF) patients combined acute renal failure (ARF).

Methods

HF patients combined ARF (n = 90) and healthy controls (n = 90) in the same period were included in our hospital from April 2016 to December 2018. Every subject was followed up for 24 months. Serum levels of lncRNA ROR and miR-125b were detected, and their expression correlation was analyzed by Pearson correlation test. Receiver operating characteristic (ROC) curves were depicted for assessing the sensitivity and specificity of lncRNA ROR and miR-125b in diagnosing HF combined ARF.

Results

lncRNA ROR was upregulated in serum of HF patients combined ARF, and its level was positively correlated to NYHA classification. miR-125b displayed an opposite trend. In serum samples of HF combined ARF, expression level of lncRNA ROR was negatively related to that of miR-125b. Diagnostic potentials of lncRNA ROR and miR-125b in HF combined ARF were confirmed by ROC curve analyses (lncRNA ROR: AUC = 0.9199, cutoff value = 5.595, sensitivity = 92.22%, and specificity = 73.33%; miR-125b: AUC = 0.8509, cutoff value = 2.290, sensitivity = 81.11%, and specificity = 74.44%). After 2-year follow-up, 16 cases were dead. Higher incidences of death and rehospitalization were observed in HF combined ARF cases expressing higher serum level of lncRNA ROR or lower level of miR-125b.

Conclusions

Serum level of lncRNA ROR is upregulated, and miR-125b is downregulated in HF patients combined ARF. Their levels are linked to NYHA classification, which can be utilized as prognostic biomarkers in HF combined ARF.

Potential of natural products in the treatment of myocardial infarction: focus on molecular mechanisms

Although conventional drugs are widely used in the prevention and treatment of cardiovascular disease (CVD), they are being used less frequently due to concerns about possible side effects over the long term. There has been a renewed research interest in medicinal plant products, and their role in protecting the cardiovascular system and treating CVD, which are now being considered as potential alternatives to modern drugs. The most important mechanism causing damage to the myocardium after heart attack and reperfusion, is increased levels of free radicals and oxidative stress. Therefore, treatment approaches often focus on reducing free radicals or enhancing antioxidant defense mechanism. It has been previously reported that bioactive natural products can protect the heart muscle in myocardial infarction (MI). Since these compounds are readily available in fruits and vegetables, they could prevent the risk of MI if they are consumed daily. Although the benefits of a healthy diet are well known, many scientific studies have focused on whether pure natural compounds can prevent and treat MI. In this review we summarize the effects of curcumin, resveratrol, quercitin, berberine, and tanshinone on MI and CVD, and focus on their proposed molecular mechanisms of action.

Reconnoitering the Role of Long-Noncoding RNAs in Hypertrophic Cardiomyopathy: A Descriptive Review

Hypertrophic cardiomyopathy (HCM) is the most common form of hereditary cardiomyopathy. It is characterized by an unexplained non-dilated hypertrophy of the left ventricle with a conserved or elevated ejection fraction. It is a genetically heterogeneous disease largely caused by variants of genes encoding for cardiac sarcomere proteins, including MYH7, MYBPC3, ACTC1, TPM1, MYL2, MYL3, TNNI3, and TNNT23. Preclinical evidence indicates that the enhanced calcium sensitivity of the myofilaments plays a key role in the pathophysiology of HCM. Notably, this is not always a direct consequence of sarcomeric variations but may also result from secondary mutation-driven alterations. Long non-coding RNAs (lncRNAs) are a large class of transcripts ≥200 nucleotides in length that do not encode proteins. Compared to coding mRNAs, most lncRNAs are not as well-annotated and their functions are greatly unexplored. Nevertheless, increasing evidence shows that lncRNAs are involved in a variety of biological processes and diseases including HCM. Accumulating evidence has indicated that lncRNAs are dysregulated in HCM, and closely related to sarcomere construction, calcium channeling and homeostasis of mitochondria. In this review, we have summarized the known regulatory and functional roles of lncRNAs in HCM.

The function of LncRNA-H19 in cardiac hypertrophy

Cardiac hypertrophy, characterized by the enlargement of cardiomyocytes, is initially an adaptive response to physiological and pathological stimuli. Decompensated cardiac hypertrophy is related to fibrosis, inflammatory cytokine, maladaptive remodeling, and heart failure. Although pathological myocardial hypertrophy is the main cause of hypertrophy-related morbidity and mortality, our understanding of its mechanism is still poor. Long noncoding RNAs (lncRNAs) are noncoding RNAs that regulate various physiological and pathological processes through multiple molecular mechanisms. Recently, accumulating evidence has indicated that lncRNA-H19 is a potent regulator of the progression of cardiac hypertrophy. For the first time, this review summarizes the current studies about the role of lncRNA-H19 in cardiac hypertrophy, including its pathophysiological processes and underlying pathological mechanism, including calcium regulation, fibrosis, apoptosis, angiogenesis, inflammation, and methylation. The context within which lncRNA-H19 might be developed as a target for cardiac hypertrophy treatment is then discussed to gain better insight into the possible biological functions of lncRNA-H19 in cardiac hypertrophy.

Serum exosomes from young rats improve the reduced osteogenic differentiation of BMSCs in aged rats with osteoporosis after fatigue loading in vivo

BACKGROUND

Osteoporosis is a major public health concern for the elderly population and is characterized by fatigue load resulting in bone microdamage. The ability of bone mesenchymal stem cells (BMSCs) to repair bone microdamage diminishes with age, and the accumulation of bone microdamage increases the risk of osteoporotic fracture. There is a lack of effective means to promote the repair of bone microdamage in aged patients with osteoporosis. Exosomes have been shown to be related to the osteogenic differentiation of BMSCs. Here, we aimed to evaluate the changes in the osteogenic differentiation capacity of BMSCs in aged osteoporotic rats after fatigue loading and the treatment potential of serum exosomes from young rats.

METHODS

The tibias of six aged osteoporotic rats were subjected to fatigue loading in vivo for 2 weeks, and the bone microdamage, microstructures, and mechanical properties were assessed. Subsequently, BMSCs were extracted to evaluate their proliferation and osteogenic differentiation abilities. In addition, the BMSCs of aged osteoporotic rats after fatigue loading were treated with serum exosomes from young rats under osteogenic induction conditions, and the expression of osteogenic-related miRNAs was quantified. The osteogenetic effects of miRNA-19b-3p in exosomes and the possible target protein PTEN was detected.

RESULTS

Obvious bone microdamage at the fatigue load stress point, the bone microstructure and biomechanical properties were not obviously changed. A decreased osteogenic differentiation ability of BMSCs was observed after fatigue loading, while serum exosomes from young rats highly expressing miRNA-19b-3p improved the decreased osteogenic differentiation ability of BMSCs. Transfection with miRNA-19b-3p mimic could promote osteoblastic differentiation of BMSCs and decreased the expression of PTEN. After transfection of miRNA-19b-3p inhibitor, the promotional effect of exosomes on bone differentiation was weakened. Treatment with transfected exosomes increased the expression of PTEN.

CONCLUSION

Serum exosomes derived from young rats can improve the decreased osteogenic differentiation ability of BMSCs in aged rats with osteoporosis after fatigue loading and can provide a new treatment strategy for the repair of bone microdamage and prevention of fractures.

Long non-coding RNAs in cardiac hypertrophy

Cardiac hypertrophy (CH) is generally considered adaptive responses that may occur after myocardial infarction, pressure overload, volume overload, inflammatory heart muscle disease, or idiopathic dilated cardiomyopathy, whereas long-term stimulation eventually leads to heart failure (HF). However, the current molecular mechanisms involved in CH are unclear. Recently, increasing evidences reveal that long non-coding RNAs (lncRNAs) play vital roles in CH. Different lncRNAs can promote or inhibit the pathological process of CH by different mechanisms, while the regulation of lncRNAs expression can improve CH. Thus, CH-related lncRNAs may become a novel field of research on CH.

Roles of ncRNAs as ceRNAs in Gastric Cancer

Although ignored in the past, with the recent deepening of research, significant progress has been made in the field of non-coding RNAs (ncRNAs). Accumulating evidence has revealed that microRNA (miRNA) response elements regulate RNA. Long ncRNAs, circular RNAs, pseudogenes, miRNAs, and messenger RNAs (mRNAs) form a competitive endogenous RNA (ceRNA) network that plays an essential role in cancer and cardiovascular, neurodegenerative, and autoimmune diseases. Gastric cancer (GC) is one of the most common cancers, with a high degree of malignancy. Considerable progress has been made in understanding the molecular mechanism and treatment of GC, but GC’s mortality rate is still high. Studies have shown a complex ceRNA crosstalk mechanism in GC. lncRNAs, circRNAs, and pseudogenes can interact with miRNAs to affect mRNA transcription. The study of the involvement of ceRNA in GC could improve our understanding of GC and lead to the identification of potential effective therapeutic targets. The research strategy for ceRNA is mainly to screen the different miRNAs, lncRNAs, circRNAs, pseudogenes, and mRNAs in each sample through microarray or sequencing technology, predict the ceRNA regulatory network, and, finally, conduct functional research on ceRNA. In this review, we briefly discuss the proposal and development of the ceRNA hypothesis and the biological function and principle of ceRNAs in GC, and briefly introduce the role of ncRNAs in the GC’s ceRNA network.

Long Non-coding RNA: A Key Regulator in the Pathogenesis of Diabetic Cardiomyopathy

In recent years, diabetes mellitus has become a global issue with increasing incidence rate worldwide. Diabetic cardiomyopathy (DCM), one of the important complications of diabetes, refers to patients with type 1 and type 2 diabetes who have ventricular hypertrophy, fibrosis and even diastolic dysfunction. The pathogenesis of DCM is related to oxidative stress, inflammatory response, apoptosis, autophagy, myocardial fibrosis and, diabetic microangiopathy. Long non-coding RNAs (lncRNA) is a non-coding RNA with a length longer than 200 nucleotides which lack the ability of protein coding. With the development of molecular technology, massive evidence demonstrates that lncRNA play a critical role in the molecular mechanism of DCM. Moreover, it can also be used as potential diagnostic markers for DCM. In this review, we intend to summarize the pathological roles and molecular mechanism of lncRNA in the progression of diabetic cardiomyopathy, which may provide promising diagnosis and treatment strategies for DCM.

Epigenetic mechanisms underlying the benefits of flavonoids in cardiovascular health and diseases: are long non-coding RNAs rising stars?

Cardiovascular diseases (CVDs) rank as the first leading cause of death globally. High dietary polyphenol (especially flavonoids) intake has strongly been associated with low incidence of the primary outcome, overall mortality, blood pressure, inflammatory biomarkers, onset of new-onset type 2 diabetes mellitus (T2DM), and obesity. Phytogenic flavonoids affect the physiological and pathological processes of CVDs by modulating various biochemical signaling pathways. Non-coding RNAs (ncRNAs) have attracted increasing attention as fundamental regulator of gene expression involved in CVDs. Among the different ncRNA subgroups, long ncRNAs (lncRNAs) have recently emerged as regulatory eukaryotic transcripts and therapeutic targets with important and diverse functions in health and diseases. lncRNAs may be associated with the initiation, development and progression of CVDs by modulating acute and chronic inflammation, adipogenesis and lipid metabolism, and cellular physiology. This review summarizes this research on the modulatory effects of lncRNAs and their roles in mediating cellular processes. The mechanisms of action of flavonoids underlying their therapeutic effects on CVDs are also discussed. Based on our review, flavonoids might facilitate a significant epigenetic modification as part (if not full) of their tissue-/cell-related biological effects. This finding may be attributed to their interaction with cellular signaling pathways involved in chronic diseases. Certain lncRNAs might be the target of specific flavonoids, and some critical signaling processes involved in the intervention of CVDs might mediate the therapeutic roles of flavonoids.

Long Noncoding RNA HOTAIR Functions as a Competitive Endogenous RNA to Regulate Connexin43 Remodeling in Atrial Fibrillation by Sponging MicroRNA-613

Several studies have indicated that long noncoding RNAs (lncRNAs)-HOX transcript antisense RNA (HOTAIR) is involved in some cardiovascular diseases by regulating gene expression as a competitive endogenous RNA (ceRNA). GJA1 encoding Cx43 is one potential target gene of microRNA-613 (miR-613). Meanwhile, there is a potential target regulatory relationship between HOTAIR and miR-613. The present study is aimed at investigating whether HOTAIR functions as a ceRNA to regulate the Cx43 expression in atrial fibrillation (AF) by sponging miR-613. The expressions of HOTAIR, miR-613, and Cx43 were detected in the right atrial appendages of 45 patients with heart valve disease, including 23 patients with chronic AF. The HOTAIR overexpressed and underexpressed HL-1 cell model were constructed to confirm the effect of HOTAIR on Cx43. Then, the Cx43 expression was detected to testify the interplay between HOTAIR and miR-613 after cotransfecting HOTAIR and miR-613. Furthermore, luciferase assays were performed to verify that HOTAIR could regulate Cx43 remolding as a ceRNA by sponging miR-613. The expression of HOTAIR and Cx43 was significantly downregulated in chronic AF group. HOTAIR regulated positively the Cx43 expression in HL-1 cells. The upregulated effect of HOTAIR on the Cx43 expression could be remarkably attenuated by miR-613. Moreover, the inhibitory effect of miR-613 on the Cx43 expression could be obviously mitigated by HOTAIR. At last, luciferase assays confirmed HOTAIR functioned as a ceRNA in the Cx43 expression by sponging miR-613. Our study suggests that HOTAIR, functioning as a ceRNA by sponging miR-613, is an important contributor to Cx43 remolding in AF.

Long Non-Coding RNAs in Atrial Fibrillation: Pluripotent Stem Cell-Derived Cardiomyocytes as a Model System

Atrial fibrillation (AF) is a type of sustained arrhythmia in humans often characterized by devastating alterations to the cardiac conduction system as well as the structure of the atria. AF can lead to decreased cardiac function, heart failure, and other complications. Long non-coding RNAs (lncRNAs) have been shown to play important roles in the cardiovascular system, including AF; however, a large group of lncRNAs is not conserved between mouse and human. Furthermore, AF has complex networks showing variations in mechanisms in different species, making it challenging to utilize conventional animal models to investigate the functional roles and potential therapeutic benefits of lncRNAs for AF. Fortunately, pluripotent stem cell (PSC)-derived cardiomyocytes (CMs) offer a reliable platform to study lncRNA functions in AF because of certain electrophysiological and molecular similarities with native human CMs. In this review, we first summarize the broad aspects of lncRNAs in various heart disease settings, then focus on their potential roles in AF development and pathophysiology. We also discuss current uses of PSCs in AF research and describe how these studies could be developed into novel therapeutics for AF and other cardiovascular diseases.

Long noncoding RNA in cardiac aging and disease

Cardiovascular diseases (CVDs) are the main cause of morbidity and mortality in Western society and present an important age-related risk. With the constant rise in life expectancy, prevalence of CVD in the population will likely increase further. New therapies, especially in the elderly, are needed to combat CVD. This review is focused on the role of long noncoding RNA (lncRNA) in CVD. RNA sequencing experiments in the past decade showed that most RNA does not code for protein, but many RNAs function as ncRNA. Here, we summarize the recent findings of lncRNA regulation in the diseased heart. The potential use of these RNAs as biomarkers of cardiac disease prediction is also discussed.

Competing Endogenous RNAs, Non-Coding RNAs and Diseases: An Intertwined Story

MicroRNAs (miRNAs), a class of small non-coding RNA molecules, are responsible for RNA silencing and post-transcriptional regulation of gene expression. They can mediate a fine-tuned crosstalk among coding and non-coding RNA molecules sharing miRNA response elements (MREs). In a suitable environment, both coding and non-coding RNA molecules can be targeted by the same miRNAs and can indirectly regulate each other by competing for them. These RNAs, otherwise known as competing endogenous RNAs (ceRNAs), lead to an additional post-transcriptional regulatory layer, where non-coding RNAs can find new significance. The miRNA-mediated interplay among different types of RNA molecules has been observed in many different contexts. The analyses of ceRNA networks in cancer and other pathologies, as well as in other physiological conditions, provide new opportunities for interpreting omics data for the field of personalized medicine. The development of novel computational tools, providing putative predictions of ceRNA interactions, is a rapidly growing field of interest. In this review, I discuss and present the current knowledge of the ceRNA mechanism and its implications in a broad spectrum of different pathologies, such as cardiovascular or autoimmune diseases, cancers and neurodegenerative disorders.

The Complex Landscape of PTEN mRNA Regulation

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a key tumor suppressor in the development and progression of different tumor types. Emerging data indicate that small reductions in PTEN protein levels can promote cancer. PTEN protein levels are tightly controlled by a plethora of mechanisms beginning with epigenetic and transcriptional regulation and ending with control of protein synthesis and stability. PTEN messenger RNA (mRNA) is also subject to exquisite regulation by microRNAs, coding and long noncoding RNAs, and RNA-binding proteins. Additionally, PTEN mRNA is markedly influenced by alternative splicing and variable polyadenylation. Herein we provide a synoptic description of the current understanding of the complex regulatory landscape of PTEN mRNA regulation including several specific processes that modulate its stability and expression, in the context of PTEN loss-associated cancers.

The Expression of microRNA in Adult Rat Heart with Isoproterenol-Induced Cardiac Hypertrophy

Cardiac hypertrophy is a common pathological condition and an independent risk factor that triggers cardiovascular morbidity. As an important epigenetic regulator, miRNA is widely involved in many biological processes. In this study, miRNAs expressed in rat hearts that underwent isoprenaline-induced cardiac hypertrophy were identified using high-throughput sequencing, and functional verification of typical miRNAs was performed using rat primary cardiomyocytes. A total of 623 miRNAs were identified, of which 33 were specifically expressed in cardiac hypertrophy rats. The enriched pathways of target genes of differentially expressed miRNAs included the FoxO signaling pathway, dopaminergic synapse, Wnt signaling pathway, MAPK (mitogen-activated protein kinase) signaling pathway, and Hippo signaling pathway. Subsequently, miR-144 was the most differentially expressed miRNA and was subsequently selected for in vitro validation. Inhibition of miR-144 expression in primary myocardial cells caused up-regulation of cardiac hypertrophy markers atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). The dual luciferase reporter system showed that ANP may be a target gene of miR-144. Long non-coding RNA myocardial infarction associated transcript (LncMIAT) is closely related to heart disease, and here, we were the first to discover that LncMIAT may act as an miR-144 sponge in isoproterenol-induced cardiac hypertrophy. Taken together, these results enriched the understanding of miRNA in regulating cardiac hypertrophy and provided a reference for preventing and treating cardiac hypertrophy.

LncRNA OIP5-AS1 facilitates gastric cancer cell growth by targeting the miR-422a/ANO1 axis

OPA-interacting protein 5 antisense transcript 1 (OIP5-AS1) plays an important regulatory role in various types of cancers. However, the functional role and regulatory mechanisms of OIP5-AS1 in gastric cancer (GC) remain largely unknown. In this study, we found that the expression of OIP5-AS1 was increased in GC tissues compared with that in adjacent non-cancerous tissues, which was significantly associated with shorter overall survival time of patients. In addition, OIP5-AS1 expression was also increased in GC cell lines including NCI-N87, MKN-45, BGC-823 and SGC-7901, when compared with that in normal gastric epithelial cell line GES-1. Knockdown of OIP5-AS1 markedly suppressed the proliferation and colony formation activities of GC cells, induced G0/G1 arrest and apoptosis of GC cells in vitro, and restrained tumor growth in vivo. Mechanistically, OIP5-AS1 functions as an oncogenic competing endogenous RNA by binding to and sequestering miR-422a to elevate the expression of anoctamin-1. Our study first demonstrated that OIP5-AS1 is a critical and powerful regulator of GC pathogenesis and may represent a novel candidate target for GC therapy.

The role and molecular mechanism of epigenetics in cardiac hypertrophy

Cardiac hypertrophy is a significant risk factor for cardiovascular disease, including heart failure, arrhythmia, and sudden death. Cardiac hypertrophy involves both embryonic gene expression and transcriptional reprogramming, which are tightly regulated by epigenetic mechanisms. An increasing number of studies have demonstrated that epigenetics plays an influential role in the occurrence and development of cardiac hypertrophy. Here, we summarize the latest research progress on epigenetics in cardiac hypertrophy involving DNA methylation, histone modification, and non-coding RNA, to help understand the mechanism of epigenetics in cardiac hypertrophy. The expression of both embryonic and functional genes can be precisely regulated by epigenetic mechanisms during cardiac hypertrophy, providing a substantial number of therapeutic targets. Thus, epigenetic treatment is expected to become a novel therapeutic strategy for cardiac hypertrophy. According to the research performed to date, epigenetic mechanisms associated with cardiac hypertrophy remain far from completely understood. Therefore, epigenetic mechanisms require further exploration to improve the prevention, diagnosis, and treatment of cardiac hypertrophy.

Expedition to the missing link: Long noncoding RNAs in cardiovascular diseases

With the advances in deep sequencing-based transcriptome profiling technology, it is now known that human genome is transcribed more pervasively than previously thought. Up to 90% of the human DNA is transcribed, and a large proportion of the human genome is transcribed as long noncoding RNAs (lncRNAs), a heterogenous group of non-coding transcripts longer than 200 nucleotides. Emerging evidence suggests that lncRNAs are functional and contribute to the complex regulatory networks involved in cardiovascular development and diseases. In this article, we will review recent evidence on the roles of lncRNAs in the biological processes of cardiovascular development and disorders. The potential applications of lncRNAs as biomarkers and targets for therapeutics are also discussed.

The Long Noncoding RNA Hotair Regulates Oxidative Stress and Cardiac Myocyte Apoptosis during Ischemia-Reperfusion Injury

Oxidative stress and subsequent cardiac myocyte apoptosis play central roles in the initiation and progression of myocardial ischemia-reperfusion (I/R) injury. Homeobox transcript antisense intergenic RNA (Hotair) was previously implicated in various heart diseases, yet its role in myocardial I/R injury has not been clearly demonstrated. Mice with cardiac-restricted knockdown or overexpression of Hotair were exposed to I/R surgery. H9c2 cells were cultured and subjected to hypoxia/reoxygenation (H/R) stimulation to further verify the role and underlying mechanisms of Hotair in vitro. Histological examination, molecular detection, and functional parameters were determined in vivo and in vitro. In response to I/R or H/R treatment, Hotair expression was increased in a bromodomain-containing protein 4-dependent manner. Cardiac-restricted knockdown of Hotair exacerbated, whereas Hotair overexpression prevented I/R-induced oxidative stress, cardiac myocyte apoptosis, and cardiac dysfunction. Mechanistically, we observed that Hotair exerted its beneficial effects via activating AMP-activated protein kinase alpha (AMPKα). Further detection revealed that Hotair activated AMPKα through regulating the enhancer of zeste homolog 2/microRNA-451/calcium-binding protein 39 (EZH2/miR-451/Cab39) axis. We provide the evidence that endogenous lncRNA Hotair is an essential negative regulator for oxidative stress and cardiac myocyte apoptosis in myocardial I/R injury, which is dependent on AMPKα activation via the EZH2/miR-451/Cab39 axis.

RP11-874J12.4 promotes oral squamous cell carcinoma tumorigenesis via the miR-19a-5p/EBF1 axis

BACKGROUND

Oral squamous cell carcinoma (OSCC) ranks as the fifth most frequent cancer worldwide, and the recurrence and migration of OSCC still pose large threats to patients. Long non-coding RNAs (lncRNAs) have recently emerged as crucial players in cancer development, and it is of great significance to understand the regulatory nexus of lncRNAs in OSCC.

METHODS

Here, we identified a novel lncRNA, RP11-874J12.4, which is ectopically expressed in OSCC and facilitates OSCC.

RESULTS

RP11-874J12.4 directly binds to and regulates miR-19a-5p. Interestingly, RP11-874J12.4 and miR-19a-5p form a negative regulatory loop that inhibits the expression of miR-19a-5p in OSCC. The expression of an oncogenic transcription factor, EBF1, is unleashed in OSCC due to the low expression of miR-19a-5p, which promotes the growth and migration of OSCC.

CONCLUSION

Our data illustrate a regulatory axis of RP11-874J12.4/miR-19a-5P/EBF1 and an inhibitory loop with RP11-874J12.4 and miR-19a-5p. These data provide insights into the tumorigenesis of OSCC and the novel drug targets for OSCC.

Regulatory RNAs in Heart Failure

Cardiovascular disease is an enormous socioeconomic burden worldwide and remains a leading cause of mortality and disability despite significant efforts to improve treatments and personalize healthcare. Heart failure is the main manifestation of cardiovascular disease and has reached epidemic proportions. Heart failure follows a loss of cardiac homeostasis, which relies on a tight regulation of gene expression. This regulation is under the control of multiple types of RNA molecules, some encoding proteins (the so-called messenger RNAs) and others lacking protein-coding potential, named noncoding RNAs. In this review article, we aim to revisit the notion of regulatory RNA, which has been thus far mainly confined to noncoding RNA. Regulatory RNA, which we propose to abbreviate as regRNA, can include both protein-coding RNAs and noncoding RNAs, as long as they contribute, directly or indirectly, to the regulation of gene expression. We will address the regulation and functional role of messenger RNAs, microRNAs, long noncoding RNAs, and circular RNAs (ie, regRNAs) in heart failure. We will debate the utility of regRNAs to diagnose, prognosticate, and treat heart failure, and we will provide directions for future work.

Interactions Among Regulatory Non-coding RNAs Involved in Cardiovascular Diseases

Non-coding RNAs (ncRNAs) are important regulatory players in human cells that have been shown to modulate different cellular processes and biological functions through controlling gene expression, being also involved in pathological conditions such as cardiovascular diseases. Among them, long non-coding RNAs (lncRNAs) and circular (circRNAs) could act as competing endogenous RNAs (ceRNAs) sequestering other ncRNAs. This entangled network of interactions has been reported to trigger the decay of the targeted ncRNAs having important roles in gene regulation. Growing evidences have been demonstrated that the regulatory mechanism underlying the crosstalk between different ncRNA species, namely lncRNAs, circRNAs and miRNAs has also an important role in the pathophysiological processes of cardiovascular diseases. In this chapter, the main regulatory relationship among lncRNAs, circRNAs and miRNAs were summarized and their role in the control and development of cardiovascular diseases was highlighted.

Non-coding RNAs and Pathological Cardiac Hypertrophy

Cardiovascular disease (CVD) is a common disease which poses a serious threat to human health and it is characterized by high prevalence, high disability and high mortality. Myocardial hypertrophy (MH) is a common pathological process of various cardiovascular diseases and is considered as an independent risk factor for increased cardiovascular morbidity and mortality. Therefore, it is particularly important to understand its pathological mechanism and treatment. In recent years, it has been found that many non-coding RNAs (ncRNAs) play key regulatory roles in humans' various pathophysiological processes. Abnormal expression of ncRNAs in different types of cardiac cells is associated with pathological cardiac hypertrophy. Understanding the relationship between various ncRNAs and intercellular communication through extracellular vesicles (EV) can identify the key ncRNAs which are the accurate targets of precise therapy in this network of action, it also can potentially be a marker for clinical disease diagnosis, which will reflect the progress of the disease earlier and more accurately. There are many factors that regulate the occurrence and development of cardiac hypertrophy, ncRNAs are only a part of them. There are also mutual promotion or inhibition between ncRNAs and other molecules. It will be helpful for us to comprehend the mechanism of cardiac hypertrophy better and provide a sufficient theoretical basis for clinical diagnosis and treatment by defining these relationships.

Transcribed Ultraconserved Regions, Uc.323, Ameliorates Cardiac Hypertrophy by Regulating the Transcription of CPT1b (Carnitine Palmitoyl transferase 1b)

Transcribed ultraconserved regions (T-UCRs) are a novel class of long noncoding RNAs transcribed from UCRs, which exhibit 100% DNA sequence conservation among humans, mice, and rats. However, whether T-UCRs regulate cardiac hypertrophy remains unclear. We aimed to explore the effects of T-UCRs on cardiac hypertrophy. First, we performed long noncoding RNA microarray analysis on hearts of mice subjected to sham surgery or aortic banding and found that the T-UCR uc.323 was decreased significantly in mice with aortic banding-induced cardiac hypertrophy. In vitro loss- and gain-of-function experiments demonstrated that uc.323 protected cardiomyocytes against hypertrophy induced by phenylephrine. Additionally, we discovered that mammalian target of rapamycin 1 contributed to phenylephrine-induced uc.323 downregulation and uc.323-mediated cardiomyocyte hypertrophy. We further mapped the possible target genes of uc.323 through global microarray mRNA expression analysis after uc.323 knockdown and found that uc.323 regulated the expression of cardiac hypertrophy-related genes such as CPT1b (Carnitine Palmitoyl transferase 1b). Then, chromatin immunoprecipitation proved that EZH2 (enhancer of zeste homolog 2) bound to the promoter of CPT1b via H3K27me3 (trimethylation of lysine 27 of histone H3) to induce CPT1b downregulation. And overexpression of CPT1b could block uc.323-mediated cardiomyocyte hypertrophy. Finally, we found that uc.323 deficiency induced cardiac hypertrophy. Our results reveal that uc.323 is a conserved T-UCR that inhibits cardiac hypertrophy, potentially by regulating the transcription of CPT1b via interaction with EZH2.

The Mechanisms Underlying PTEN Loss in Human Tumors Suggest Potential Therapeutic Opportunities

In this review, we will first briefly describe the diverse molecular mechanisms associated with PTEN loss of function in cancer. We will then proceed to discuss the molecular mechanisms linking PTEN loss to PI3K activation and demonstrate how these mechanisms suggest possible therapeutic approaches for patients with PTEN-null tumors.

Myocardial hypertrophy is improved with berberine treatment via long non-coding RNA MIAT-mediated autophagy

Objectives

This study aimed to evaluate berberine (BBR) effects on myocardial hypertrophy (MH) and associated mechanisms.

Methods

BBR effects on MH were evaluated in rats with constriction of abdominal aorta (CAA). qRT-PCR assay was used to measure MH-related genes, long non-coding RNAs (lncRNAs) and autophagy-related genes expressions. Western blot was performed to detect autophagy markers expression. Filamentous actin and phalloidin expressions were detected using immunofluorescence assay.

Key findings

BBR significantly attenuated CAA-induced MH and cardiomyocyte enlargement. CAA upregulated β myosin heavy chain and atrial natriuretic peptide expressions in heart tissues, which was attenuated by BBR. BBR suppressed myocardial infarction associated transcript (MIAT) expression in rats with CAA. p62 mRNA expression was upregulated and beclin1 and autophagy related 5 were downregulated in CAA versus control groups. The effects were abolished by BBR. In vitro studies showed that BBR ameliorated angiotensin II-induced MH and attenuated Ang II-induced MIAT expression in H9C2 cells. Expressions of phosphorylated mTOR, phosphorylated AMPK and LC3 were upregulated in H9C2 cells after Ang II stimulation, and the effects were abolished by BBR.

Conclusions

BBR exerted beneficial effects on MH induced by CCA, and the mechanisms were associated with decreased MIAT expression and enhanced autophagy.

Long noncoding RNA lnc-DILC stabilizes PTEN and suppresses clear cell renal cell carcinoma progression

Background

Increasing evidence has indicated that long noncoding RNAs (lncRNAs) are crucial regulators affecting the progression of human cancers. Recently, lncRNA downregulated in liver cancer stem cells (lnc-DILC) was identified to function as a tumor suppressor inhibiting the tumorigenesis and metastasis in liver cancer and colorectal cancer. However, to date, little is known about the functional roles of lnc-DILC in modulating malignant phenotypes of clear cell renal cell carcinoma (ccRCC) cells.

Methods

lnc-DILC expression in human ccRCC tissues was detected by qRT-PCR. Overexpression and knockdown experiments were carried out to determine the effects of lnc-DILC on ccRCC cell proliferation, migration and invasion. To reveal the underlying mechanisms of lnc-DILC functions in ccRCC cells. RNA immunoprecipitation, RNA pull-down, in vivo ubiquitination, co-immunoprecipitation and western blot assays were performed.

Results

Here, we identified that lnc-DILC levels were dramatically downregulated in ccRCC tissues. Loss of lnc-DILC expression was correlated with larger tumor size, advanced tumor grade and lymph node metastasis, and also predicted worse prognosis in patients with ccRCC. Functionally, knockdown and overexpression experiments demonstrated that lnc-DILC inhibited cell proliferation, migration and invasion in ccRCC cells. Mechanistic investigation revealed that lnc-DILC bound to tumor suppressor PTEN and suppressed its degradation. lnc-DILC repressed the PTEN ubiquitination through blocking the interaction between PTEN and E3 ubiquitin ligase WWP2 and recruiting the deubiquitinase USP11 to PTEN. Moreover, we demonstrated that PTEN–AKT signaling was crucial for lnc-DILC-mediated suppressive effects.

Conclusions

In summary, our research revealed a novel mechanism by which lnc-DILC regulates PTEN stability via WWP2 and USP11, and shed light on potential therapeutic strategies by the restoration of lnc-DILC expression in patients with ccRCC.

Epigenetic Modifications in Cardiovascular Aging and Diseases

Aging is associated with a progressive decline in cardiovascular structure and function. Accumulating evidence links cardiovascular aging to epigenetic alterations encompassing a complex interplay of DNA methylation, histone posttranslational modifications, and dynamic nucleosome occupancy governed by numerous epigenetic factors. Advances in genomics technology have led to a profound understanding of chromatin reorganization in both cardiovascular aging and diseases. This review summarizes recent discoveries in epigenetic mechanisms involved in cardiovascular aging and diseases and discusses potential therapeutic strategies to retard cardiovascular aging and conquer related diseases through the rejuvenation of epigenetic signatures to a young state.

Endoplasmic reticulum stress-induced iRhom2 up-regulation promotes macrophage-regulated cardiac inflammation and lipid deposition in high fat diet (HFD)-challenged mice: Intervention of fisetin and metformin

Endoplasmic reticulum stress (ERS) has been implicated in obesity-associated cardiac remodeling and dysfunction. Inactive rhomboid protein 2 (iRhom2), also known as Rhbdf2, is an inactive member of the rhomboid intramembrane proteinase family, playing an essential role in regulating inflammation. Nevertheless, the role of ERS-meditated iRhom2 pathway in metabolic stress-induced cardiomyopathy remains unknown. In the study, we showed that 4-PBA, as an essential ERS inhibitor, significantly alleviated high fat diet (HFD)-induced metabolic disorder and cardiac dysfunction in mice. Additionally, lipid deposition in heart tissues was prevented by 4-PBA in HFD-challenged mice. Moreover, 4-PBA blunted the expression of iRhom2, TACE, TNFR2 and phosphorylated NF-κB to prevent HFD-induced expression of inflammatory factors. Further, 4-PBA restrained HFD-triggered oxidative stress by promoting Nrf-2 signaling. Importantly, 4-PBA markedly suppressed cardiac ERS in HFD mice. The anti-inflammation, anti-ERS and anti-oxidant effects of 4-PBA were verified in palmitate (PAL)-incubated macrophages and cardiomyocytes. In addition, promoting ERS could obviously enhance iRhom2 signaling in vitro. Intriguingly, our data demonstrated that PAL-induced iRhom2 up-regulation apparently promoted macrophage to generate inflammatory factors that could promote cardiomyocyte inflammation and lipid accumulation. Finally, interventions by adding fisetin or metformin significantly abrogated metabolic stress-induced cardiomyopathy through the mechanisms mentioned above. In conclusion, this study provided a novel mechanism for metabolic stress-induced cardiomyopathy pathogenesis. Therapeutic strategy to restrain ROS/ERS/iRhom2 signaling pathway could be developed to prevent myocardial inflammation and lipid deposition, consequently alleviating obesity-induced cardiomyopathy.

Novel reciprocal interaction of lncRNA HOTAIR and miR-214-3p contribute to the solamargine-inhibited PDPK1 gene expression in human lung cancer

Solamargine (SM) has been shown to have anti‐cancer properties. However, the underlying mechanism involved remains undetermined. We showed that SM inhibited the growth of non‐small cell lung cancer (NSCLC) cells, which was enhanced in cells with silencing of long non‐coding RNA (lncRNA) HOX transcript antisense RNA (HOTAIR), while it overcame by overexpression of HOTAIR. In addition, SM increased the expression of miR‐214‐3p and inhibited 3‐phosphoinositide‐dependent protein kinase‐1 (PDPK1) gene expression, which was strengthened by miR‐214‐3p mimics. Intriguingly, HOTAIR could directly bind to miR‐214‐3p and sequestered miR‐214‐3p from the target gene PDPK1. Intriguingly, overexpression of PDPK1 overcame the effects of SM on miR‐214‐3p expressions and neutralized the SM‐inhibited cell growth. Similar results were observed in vivo. In summary, our results showed that SM‐inhibited NSCLC cell growth through the reciprocal interaction between HOTAIR and miR‐214‐3p, which ultimately suppressed PDPK1 gene expression. HOTAIR effectively acted as a competing endogenous RNA (ceRNA) to stimulate the expression of target gene PDPK1. These complex interactions and feedback mechanisms contribute to the overall effect of SM. This unveils a novel molecular mechanism underlying the anti‐cancer effect of SM in human lung cancer.

Circulating miRNAs as Potential Biomarkers Associated with Cardiac Remodeling and Fibrosis in Chagas Disease Cardiomyopathy

Chagas disease (CD) affects approximately 6-7 million people worldwide, from which 30% develop chronic Chagas cardiomyopathy (CCC), usually after being asymptomatic for years. Currently available diagnostic methods are capable of adequately identifying infected patients, but do not provide information regarding the individual risk of developing the most severe form of the disease. The identification of biomarkers that predict the progression from asymptomatic or indeterminate form to CCC, may guide early implementation of pharmacological therapy. Here, six circulating microRNAs (miR-19a-3p, miR-21-5p, miR-29b-3p, miR-30a-5p, miR-199b-5p and miR-208a-3p) were evaluated and compared among patients with CCC (n = 28), CD indeterminate form (n = 10) and healthy controls (n = 10). MiR-19a-3p, miR-21-5p, and miR-29b-3p were differentially expressed in CCC patients when compared to indeterminate form, showing a positive correlation with cardiac dysfunction, functional class, and fibrosis, and a negative correlation with ejection fraction and left ventricular strain. Cardiac tissue analysis confirmed increased expression of microRNAs in CCC patients. In vitro studies using human cells indicated the involvement of these microRNAs in the processes of cardiac hypertrophy and fibrosis. Our study suggests that miRNAs are involved in the process of cardiac fibrosis and remodeling presented in CD and indicate a group of miRNAs as potential biomarkers of disease progression in CCC.

Long Noncoding Competing Endogenous RNA Networks in Age-Associated Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the most serious health problem in the world, displaying high rates of morbidity and mortality. One of the main risk factors for CVDs is age. Indeed, several mechanisms are at play during aging, determining the functional decline of the cardiovascular system. Aging cells and tissues are characterized by diminished autophagy, causing the accumulation of damaged proteins and mitochondria, as well as by increased levels of oxidative stress, apoptosis, senescence and inflammation. These processes can induce a rapid deterioration of cellular quality-control systems. However, the molecular mechanisms of age-associated CVDs are only partially known, hampering the development of novel therapeutic strategies. Evidence has emerged indicating that noncoding RNAs (ncRNAs), such as long ncRNAs (lncRNAs) and micro RNAs (miRNAs), are implicated in most patho-physiological mechanisms. Specifically, lncRNAs can bind miRNAs and act as competing endogenous-RNAs (ceRNAs), therefore modulating the levels of the mRNAs targeted by the sponged miRNA. These complex lncRNA/miRNA/mRNA networks, by regulating autophagy, apoptosis, necrosis, senescence and inflammation, play a crucial role in the development of age-dependent CVDs. In this review, the emerging knowledge on lncRNA/miRNA/mRNA networks will be summarized and the way in which they influence age-related CVDs development will be discussed.

Exenatide promotes cardiac lncRNAs HOX transcript antisense RNA (HOTAIR) in Wistar rats with liver cirrhosis; a novel role of GLP-1 receptor agonists in cirrhotic cardiomyopathy

Long acting non-coding RNAs lncRNAs HOX Transcript Antisense RNA (HOTAIR) is cardioprotective and mediates its effect through sirtulin 1 (SIRT1). The decrease in HOTAIR expression predisposes to various types of cardiomyopathy. We aimed to investigate whether decrease HOTAIR expression is involved in cirrhotic cardiomyopathy or not and the role of glucagon like peptide 1 receptor (GLP-1 receptor) in facilitating its effect through studying the effect of a exenatide (EXA), on cardiac function as well as the expression of some relevant bio-molecules. Rats were used and divided into: naïve, EXA, Thioacetamide (TAA) and TAA + EXA groups. ECG, dobutamine stress test (DST) were done. AST, ALT, fasting blood glucose, troponin I were measured. Cardiac HOTAIR & SIRT1, hepatic and cardiac GLP-1 receptor expression levels were investigated in addition to histological studies. Our results showed that EXA administration in control rats produced no significant changes. TAA induced cirrhosis with insulin resistance and significant changes in cardiac functions. GLP-1 receptor, HOTAIR and SIRT1 expression in cardiac tissue were significantly decreased with a significant increase in troponin I. EXA + TAA group showed a restoration of the hepatic architecture and function. EXA treatment produced significant improvement in cardiac parameters and was associated with increasing the expression of cardiac GLP-1 receptor, HOTAIR. The cardiac muscle showed an apparent decrease in collagen fibers. So we can conclude that EXA promotes the protective effect of HOTAIR on cardiac structure and function in rat model of cirrhosis which may introduce a new therapeutic strategy in cirrhotic cardiomyopathy.