The circulating LncRNA SNHG15/miR-346 axis may be a potential biomarker of cardiomyocyte apoptosis during myocardial ischemia/reperfusion injury

MicroRNA-specific therapeutic targets and biomarkers of apoptosis following myocardial ischemia-reperfusion injury

MicroRNAs are single-stranded non-coding RNAs that participate in post-transcriptional regulation of gene expression, it is involved in the regulation of apoptosis after myocardial ischemia-reperfusion injury. For example, the alteration of mitochondrial structure is facilitated by MicroRNA-1 through the regulation of apoptosis-related proteins, such as Bax and Bcl-2, thereby mitigating cardiomyocyte apoptosis. MicroRNA-21 not only modulates the expression of NF-κB to suppress inflammatory signals but also activates the PI3K/AKT pathway to mitigate ischemia-reperfusion injury. Overexpression of MicroRNA-133 attenuates reactive oxygen species (ROS) production and suppressed the oxidative stress response, thereby mitigating cellular apoptosis. MicroRNA-139 modulates the extrinsic death signal of Fas, while MicroRNA-145 regulates endoplasmic reticulum calcium overload, both of which exert regulatory effects on cardiomyocyte apoptosis. Therefore, the article categorizes the molecular mechanisms based on the three classical pathways and multiple signaling pathways of apoptosis. It summarizes the targets and pathways of MicroRNA therapy for ischemia-reperfusion injury and analyzes future research directions.

Long Noncoding RNA SNHG4 Attenuates the Injury of Myocardial Infarction via Regulating miR-148b-3p/DUSP1 Axis

Objective

Long noncoding RNAs (lncRNAs), including some members of small nucleolar RNA host gene (SNHG), are important regulators in myocardial injury, while the role of SNHG4 in myocardial infarction (MI) is rarely known. This study is aimed at exploring the regulatory role and mechanisms of SNHG4 on MI.

Methods

Cellular and rat models of MI were established. The expression of relating genes was measured by qRT-PCR and/or western blot. In vitro, cell viability was detected by MTT assay, and cell apoptosis was assessed by caspase-3 level, Bax/Bcl-2 expression, and/or flow cytometry. The inflammation was evaluated by TNF-α, IL-1β, and IL-6 levels. The myocardial injury in MI rats was evaluated by echocardiography, TTC/HE/MASSON/TUNEL staining, and immunohistochemistry (Ki67). DLR assay was performed to confirm the target relationships.

Results

SNHG4 was downregulated in hypoxia-induced H9c2 cells and MI rats, and its overexpression enhanced cell viability and inhibited cell apoptosis and inflammation both in vitro and in vivo. SNHG4 overexpression also decreased infarct and fibrosis areas, relieved pathological changes, and improved heart function in MI rats. In addition, miR-148b-3p was an action target of SNHG4, and its silencing exhibited consistent results with SNHG4 overexpression in vitro. DUSP1 was a target of miR-148b-3p, which inhibited the apoptosis of hypoxia-induced H9c2 cells. Both miR-148b-3p overexpression and DUSP1 silencing weakened the effects of SNHG4 overexpression on protecting H9c2 cells against hypoxia.

Conclusions

Overexpression of SNHG4 relieved MI through regulating miR-148b-3p/DUSP1, providing potential therapeutic targets.

Research advances on circulating Long noncoding RNAs as biomarkers of cardiovascular diseases

Cardiovascular diseases (CVD) such as myocardial ischemia, myocardial infarction, heart failure, atherosclerosis, hypertension, arrhythmia, and their complications diseases are associated with increased morbidity and mortality, it is necessary to develop new diagnostic markers for CVD. LncRNAs have become a new class of biomarkers in CVD with good development prospects. Numerous studies have confirmed lncRNAs feasibility as diagnostic, prognostic and predictive tools for different types of CVD. In this review, we summarized the available knowledge regarding the clinical application value and pathophysiological mechanism of circulating lncRNA as potential biomarkers of cardiovascular disease. We reviewed the scope of application and changes of circulating lncRNAs such as ZFAS1, CDR1AS, CHAST, UCA1, HOTAIR, MIAT, NEAT1, LIPCAR, H19, NRF, NRON, MHRT, PVT1, Heat2, CASC7, GAS5, MALAT1, APPAT, HIF1A-AS1, KCNQ1OT1, NEXN in different kinds of CVD and discussed their clinical application potential as biomarker, which can help us better understand the mechanism of CVD.

lncRNA SNHG15 Induced by SOX12 Promotes the Tumorigenic Properties and Chemoresistance in Cervical Cancer via the miR-4735-3p/HIF1a Pathway

Cervical cancer (CC) is one of the most common malignancies in females, with high prevalence and mortality globally. Despite advances in diagnosis and therapeutic strategies developed in recent years, CC is still a major health burden worldwide. The molecular mechanisms underlying the development of CC need to be understood. In this study, we aimed to demonstrate the role of lncRNA SNHG15 in CC progression. Using qRT-PCR, we determined that lncRNA SNHG15 is highly expressed in CC tumor tissues and cells. lncRNA SNHG15 knockdown also reduces the tumorigenic properties of CC in vitro, as determined using the MTT, EdU, flow cytometry, and transwell assays. Using bioinformatics analysis, RNA pull-down, ChIP, and luciferase reporter assays, we verified the molecular mechanisms of lncRNA SNHG15 in CC progression and found that lncRNA SNHG15 expression in CC cells is transcriptionally regulated by SOX12; moreover, lncRNA SNHG15 promotes CC progression via the miR-4735-3p/HIF1a axis. This study can provide a potential target for CC diagnosis or therapeutic strategies in the future.