MicroRNA-mediated regulation of glucose and lipid metabolism

Contributions of microRNAs to Peripheral Insulin Sensitivity

An extensive literature base combined with advances in sequencing technologies demonstrate microRNA levels correlate with various metabolic diseases. Mechanistic studies also establish microRNAs regulate central metabolic pathways and thus play vital roles in maintaining organismal energy balance and metabolic homeostasis. This review highlights research progress on the roles and regulation of microRNAs in the peripheral tissues that confer insulin sensitivity. We discuss sequencing technologies used to comprehensively define the target spectrum of microRNAs in metabolic disease that complement studies reporting physiologic roles for microRNAs in the regulation of glucose and lipid metabolism in animal models. We also discuss the emerging roles of exosomal microRNAs as endocrine signals to regulate lipid and carbohydrate metabolism.

Therapeutic Metabolic Reprograming Using microRNAs: From Cancer to HIV Infection

MicroRNAs (miRNAs) are crucial regulators of cellular processes, including metabolism. Attempts to use miRNAs as therapeutic agents are being explored in several areas, including the control of cancer progression. Recent evidence suggests fine tuning miRNA activity to reprogram tumor cell metabolism has enormous potential as an alternative treatment option. Indeed, cancer growth is known to be linked to profound metabolic changes. Likewise, the emerging field of immunometabolism is leading to a refined understanding of how immune cell proliferation and function is governed by glucose homeostasis. Different immune cell types are now known to have unique metabolic signatures that switch in response to a changing environment. T-cell subsets exhibit distinct metabolic profiles which underlie their alternative differentiation and phenotypic functions. Recent evidence shows that the susceptibility of CD4+ T-cells to HIV infection is intimately linked to their metabolic activity, with many of the metabolic features of HIV-1-infected cells resembling those found in tumor cells. In this review, we discuss the use of miRNA modulation to achieve metabolic reprogramming for cancer therapy and explore the idea that the same approach may serve as an effective mechanism to restrict HIV replication and eliminate infected cells.

Exosomal microRNAs as Potential Biomarkers and Therapeutic Agents for Acute Ischemic Stroke: New Expectations

The morbidity and mortality rates of ischemic stroke (IS) are very high, and IS constitutes one of the main causes of disability and death worldwide. The pathogenesis of ischemic stroke includes excitotoxicity, calcium overload, oxygen radical injury, inflammatory reactions, necrosis/apoptosis, destruction of the blood-brain barrier (BBB), and other pathologic processes. Recent studies have shown that exosomes are critical to the pathogenesis, diagnosis, and treatment of cerebral infarctions resulting from ischemic stroke; and there is growing interest in the role of exosomes and exosomal miRNAs in the diagnosis and treatment of IS. Exosomes from central nervous system cells can be found in cerebrospinal fluid and peripheral bodily fluids, and exosomal contents have been reported to change with disease occurrence. Exosomes are small membranous extracellular vesicles (EVs), 30–150 nm in diameter, that are released from the cell membrane into the depressions that arise from the membranes of multivesicular bodies. Exosomes carry lipids, proteins, mRNAs, and microRNAs (miRNAs) and transport information to target cells. This exosomal transfer of functional mRNAs/miRNAs and proteins ultimately affects transcription and translation within recipient cells. Exosomes are EVs with a double-membrane structure that protects them from ribonucleases in the blood, allowing exosomal miRNAs to be more stable and to avoid degradation. New evidence shows that exosomes derived from neural cells, endothelial cells, and various stem cells create a fertile environment that supports the proliferation and growth of neural cells and endothelial cells, inhibits apoptosis and inflammatory responses, and promotes angiogenesis. In the present review, we discuss how circulating exosomes—and exosomal miRNAs in particular—may provide novel strategies for the early diagnosis and treatment of ischemic stroke via their potential as non-invasive biomarkers and drug carriers.

The Regulation Mechanisms and Clinical Application of MicroRNAs in Myocardial Infarction: A Review of the Recent 5 Years

Myocardial infarction (MI) is the most frequent end-point of cardiovascular pathology, leading to higher mortality worldwide. Due to the particularity of the heart tissue, patients who experience ischemic infarction of the heart, still suffered irreversible damage to the heart even if the vascular reflow by treatment, and severe ones can lead to heart failure or even death. In recent years, several studies have shown that microRNAs (miRNAs), playing a regulatory role in damaged hearts, bring light for patients to alleviate MI. In this review, we summarized the effect of miRNAs on MI with some mechanisms, such as apoptosis, autophagy, proliferation, inflammatory; the regulation of miRNAs on cardiac structural changes after MI, including angiogenesis, myocardial remodeling, fibrosis; the application of miRNAs in stem cell therapy and clinical diagnosis; other non-coding RNAs related to miRNAs in MI during the past 5 years.

Circulating miRNA as potential biomarkers for diabetes mellitus type 2: should we focus on searching for sex differences?

microRNAs are non-coding molecules, approximately 22 nucleotides in length, that regulate various cellular processes. A growing body of evidence has suggested that their dysregulated expression is involved in the pathogenesis of diverse diseases, including diabetes mellitus type 2 (DM2). Early onset of this chronic and complex metabolic disorder is frequently undiagnosed, leading to the development of severe diabetic complications. Notably, DM2 prevalence is rising globally and an increasing number of articles demonstrate that DM2 susceptibility, development, and progression differ between males and females. Therefore, this paper discusses the role of microRNAs as a source of novel diagnostic biomarkers for DM2 and aims to underline the importance of sex disparity in biomarkers research. Taking into account an urgent need for the development of sex-specific diagnostic strategies in DM2, recent results have shown that circulating miRNAs are promising candidates for sex-biased biomarkers.

ceRNA Network Analysis Reveals AP-1 Transcription Factor Components as Potential Biomarkers for Alzheimer’s Disease

BACKGROUND

Alzheimer's disease (AD) is a progressive neurodegenerative disease affecting the elderly, characterized by decreased cognitive function. Non-coding RNAs contribute to AD pathogenesis.

OBJECTIVE

To identify potential therapeutic targets for AD, competing endogenous RNA (ceRNA) networks were constructed using the hippocampus of 6-month-old amyloid precursor protein/ presenilin 1 double transgenic (APP/PS1) and wild-type mice.

METHODS

RNA-seq data (GSE158995), generated from the hippocampus of APP/PS1 and wild-type mice, were analyzed with the limma R package to identify significantly differentially expressed mRNAs and circRNAs (DEMs and DECs, respectively). DEM Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed using Enrichr (https://maayanlab.cloud/Enrichr/). Correlations between DEMs and DECs were determined using the ggcorrplot R package. Main clusters and hub DEMs were selected using the STRING database and Cytoscape software. ceRNA interactions were predicted with the miRTarbase and Starbase tools and constructed with the ggalluvial R package and Cytoscape software. ceRNA networks were validated using the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot.

RESULTS

198 DEMs and 90 DECs were differentially expressed in APP/PS1 vs. wild-type hippocampus. DEM GO analysis revealed significant enrichment in transcription regulation, which was subdivided into three main clusters: transcription regulation, synaptic plasticity, and protein refolding. Within the transcription regulation cluster, AP-1 transcription factor components serve as hub genes. The mmu_circ_0001787(circGLCE)/miR-339-5p/Junb and mmu_circ_0001899(circFAM120C)/ miR-181a-5p/Egr1 ceRNA networks were established based on qRT-PCR and Western blot analysis.

CONCLUSION

Two AP-1 transcription factor component-related ceRNA networks, circGLCE/miR- 339-5p/Junb and circFAM120C/miR-181a-5p/Egr1, were constructed using a mouse model of AD. These ceRNA networks may contribute to transcription regulation in AD and provide potential biomarkers for AD diagnosis and treatment.

Expression patterns of serum MicroRNAs related to endothelial dysfunction in patients with subclinical hypothyroidism

BACKGROUND

Increasing evidence has shown that elevated Thyroid stimulating hormone (TSH) levels are positively correlated with atherosclerosis (ATH) in patients with subclinical hypothyroidism (SCH). Some researchers found that the dysfunction of Endothelial Cells (ECs) in SCH plays an important role in the pathogenesis of ATH in SCH, but the association remains controversial.

OBJECTIVES

To determine the expression profiles of serum microRNAs critical to the function of Endothelial cells (ECs) may help reanalyze the possible mechanism underlying ATH in SCH and the association between ATH and SCH.

METHODS

We used qRT-PCR to perform microRNA profiling and analysis in normal control subjects (NC), patients with SCH alone (SCH), patients with SCH and ATH (SCH+ATH), and patients with ATH without SCH (ATH).

RESULTS

Both miR-221-3p and miR-222-3p showed a decreasing expression trend between the SCH and SCH+ATH groups. In addition, miR-126-3p and miR-150-5p showed a stepwise decrease from the NC to SCH groups and then to the SCH+ATH or ATH group. miR-21-5p was unregulated in the SCH, SCH+ATH, and ATH groups. Furthermore, elevated levels of miR-21-5p in SCH+ATH group were higher than SCH and ATH group. No differences were found in the levels of miR-150, miR-126, miR-221 and miR-222 between the ATH and the SCH+ATH subjects.

CONCLUSIONS

miR-21-5p may be involved in the atherosclerosis process in patients with SCH (SCH and SCH+ATH groups). miR-150-5p may be sensitive risk markers for predicting endothelial dysfunction in patients with ATH (ATH and SCH+ATH groups).

Ratiometric FRET Encoded Hierarchical ZrMOF @ Au Cluster for Ultrasensitive Quantifying MicroRNA In Vivo

Here, Zirconium metal-organic frameworks @ gold (ZrMOF @ Au) cluster architectures have been fabricated and then functionalized with two fluorescent dyes (Quasar [QS] and Cyanine5.5 [Cy5.5]) through deoxyribonucleic acid hybridization, to form a fluorescence resonance energy transfer (FRET) encoded ZrMOF  @  Au-QS/Cy5.5 complex. In the presence of the target intracellular microRNA (miR)-21, the fluorescence of Cy5.5 at 705 nm (F₇₀₅ ) decreases and the fluorescence of QS at 665 nm (F₆₆₅ ) increases when Cy5.5 is released from the surface of ZrMOF  @  Au-QS/Cy5.5. The change in the fluorescence ratio (F₇₀₅ /F₆₆₅ ) shows an outstanding linear range of 0.006-67.9 amol/ng_RNA , and the limit of detection is 4.51 zmol/ng_RNA in living cells. The high ratio loading of nucleic acid on surface of ZrMOF @ Au cluster and two fluorescence encoded signal enables better sensitivity and reliability. Zeptomolar sensitivity and good linearity against target affords distinct imaging-based monitoring of the cancer marker miR-21 both in living cells and in vivo. At the same time, the architecture displays remarkable photothermal conversion efficiency (53.7%) and gives rise to outstanding therapy ability in vivo. This strategy offers new avenues for the intelligent quantification of miRNAs for simultaneous diagnoses and treatments of early-stage cancers.

Transcript Expression Profiles and MicroRNA Regulation Indicate an Upregulation of Processes Linked to Oxidative Stress, DNA Repair, Cell Death, and Inflammation in Type 1 Diabetes Mellitus Patients

Type 1 diabetes (T1D) arises from autoimmune-mediated destruction of insulin-producing β-cells leading to impaired insulin secretion and hyperglycemia. T1D is accompanied by DNA damage, oxidative stress, and inflammation, although there is still scarce information about the oxidative stress response and DNA repair in T1D pathogenesis. We used the microarray method to assess mRNA expression profiles in peripheral blood mononuclear cells (PBMCs) of 19 T1D patients compared to 11 controls and identify mRNA targets of microRNAs that were previously reported for T1D patients. We found 277 differentially expressed genes (220 upregulated and 57 downregulated) in T1D patients compared to controls. Analysis by gene sets (GSA and GSEA) showed an upregulation of processes linked to ROS generation, oxidative stress, inflammation, cell death, ER stress, and DNA repair in T1D patients. Besides, genes related to oxidative stress responses and DNA repair (PTGS2, ATF3, FOSB, DUSP1, and TNFAIP3) were found to be targets of four microRNAs (hsa-miR-101, hsa-miR148a, hsa-miR-27b, and hsa-miR-424). The expression levels of these mRNAs and microRNAs were confirmed by qRT-PCR. Therefore, the present study on differential expression profiles indicates relevant biological functions related to oxidative stress response, DNA repair, inflammation, and apoptosis in PBMCs of T1D patients relative to controls. We also report new insights regarding microRNA-mRNA interactions, which may play important roles in the T1D pathogenesis.

Effect of Xuezhikang Therapy on Expression of Pulmonary Hypertension Related miR-638 in Patients With Low HDL-C Levels

Objective: Low plasma level of high-density lipoprotein cholesterol (HDL-C) associated with poor outcomes in several cardiovascular diseases, including pulmonary arterial hypertension (PAH). Regulation of miR-638 have been proved to be associated with PAH. The aim of this study was to evaluate the expression of miR-638 after Xuezhikang (XZK) therapy in patients with low HDL-C.

Methods: Plasma levels of miR-638 were quantified by real-time polymerase chain reactions in 20 patients with PAH and 30 healthy controls. A total of 40 subjects with low HDL-C were assigned to receive an XZK therapy for 6 months. The miR-638 expression profiles were detected in PAH patients, XZK-treated subjects and lovastatin treated pulmonary arterial smooth muscle cells (PA-SMCs).

Results: The relative expression level of miR-638 in the plasma was lower in the PAH patients than that in the controls (p < 0.001). An increase of 11.2% from baseline in the HDL-C level was found after XZK therapy (p < 0.001). The relative expression of miR-638 was increased after XZK treatment (p < 0.01). The changes of miR-638 were inversely associated with baseline HDL-C levels. A significantly reduction in miR-638 expression were found in PDGF-BB-treated hPA-SMCs compared to the control cells, and the pre-treatment of the cells with lovastatin significantly re-gain the expression levels in miR-638.

Conclusion: In patients with low HDL-C levels, XZK therapy raised the expression of miR-638, suggesting that the potential therapeutic effect of XZK in PAH patients with low serum HDL-C levels deserves further exploration.

Methyl ferulic acid ameliorates alcohol-induced hepatic insulin resistance via miR-378b-mediated activation of PI3K-AKT pathway

A previous study indicated that microRNA-378b (miR-378b) plays a critical role in controlling hepatic insulin resistance by targeting insulin receptor (IR) and p110α in alcoholic liver disease (ALD). Methyl ferulic acid (MFA), a bioactive ingredient in Securidaca inappendiculata Hassk rhizomes, exhibits multiple pharmacological activities. It has been reported that MFA ameliorates insulin resistance in ALD, whereas the underlying molecular mechanism remains unclear. The objective of study was to evaluate the influence of MFA on insulin sensitivity in ethanol-induced L-02 cells as well as alcohol-fed mice and illuminate the function of miR-378b-mediated phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway in system. MFA was found to remarkably down-regulate miR-378b level and increase IR and p110α expressions. Furthermore, the effect of MFA on modulating miR-378b/PI3K-AKT pathway to enhance insulin sensitivity was corroborated by overexpressing and inhibiting miR-378b. Taken together, MFA exhibited a positive effect against ALD by attenuating the inhibition of miR-378b on IR/p110α and partly activating the insulin signaling to alleviate alcohol-induced hepatic insulin resistance.

DNA Logic Circuits for Multiple Tumor Cells Identification Using Intracellular MicroRNA Molecular Bispecific Recognition

The aberrant expression level of intracellular microRNAs (miRNAs) holds great promise for differentiating cell types at the molecular level. However, cell subtype discrimination based on a single miRNA molecular level is not sufficient and reliable. Herein, multiple identifiable and reporting modules are integrated into a single DNA circuit for multiple cancer cell subtypes identification based on miRNAs bispecific recognition. The DNA three-dimensional (3D) logic gate nano-hexahedron framework extends three recognition modules and three reporting modules to form three "AND" logic gates. Each Boolean operator "AND" returns an "ON" signal in the presence of bispecific miRNAs, simultaneously enabling three types of cell subtype identification. It not only enables the discrimination of cancer cells A549 and MCF-7 from normal cells NHDF but also successfully distinguishes different types of cancer cells. The bispecific intracellular miRNA controllable DNA circuit, with low signal-to-noise ratio, easily extends to various cell type discrimination by adjusting the miRNA species, provides huge opportunities for accurately differentiating multiple cell types at the molecular level.

The aetiology and molecular landscape of insulin resistance

Insulin resistance, defined as a defect in insulin-mediated control of glucose metabolism in tissues - prominently in muscle, fat and liver - is one of the earliest manifestations of a constellation of human diseases that includes type 2 diabetes and cardiovascular disease. These diseases are typically associated with intertwined metabolic abnormalities, including obesity, hyperinsulinaemia, hyperglycaemia and hyperlipidaemia. Insulin resistance is caused by a combination of genetic and environmental factors. Recent genetic and biochemical studies suggest a key role for adipose tissue in the development of insulin resistance, potentially by releasing lipids and other circulating factors that promote insulin resistance in other organs. These extracellular factors perturb the intracellular concentration of a range of intermediates, including ceramide and other lipids, leading to defects in responsiveness of cells to insulin. Such intermediates may cause insulin resistance by inhibiting one or more of the proximal components in the signalling cascade downstream of insulin (insulin receptor, insulin receptor substrate (IRS) proteins or AKT). However, there is now evidence to support the view that insulin resistance is a heterogeneous disorder that may variably arise in a range of metabolic tissues and that the mechanism for this effect likely involves a unified insulin resistance pathway that affects a distal step in the insulin action pathway that is more closely linked to the terminal biological response. Identifying these targets is of major importance, as it will reveal potential new targets for treatments of diseases associated with insulin resistance.

CircCD44 plays oncogenic roles in triple-negative breast cancer by modulating the miR-502-5p/KRAS and IGF2BP2/Myc axes

BACKGROUND

Emerging studies have revealed the potent functions of circRNAs in breast cancer tumorigenesis. However, the biogenesis, biofunction and mechanism of circRNAs in triple-negative breast cancer (TNBC) are largely unknown.

METHODS

High-throughput RNA sequencing was applied to identify dysregulated circRNAs in TNBCs and paired normal tissues. RNA pulldown and luciferase assays were performed to investigate the interaction between circular CD44 (circCD44, also annotated as hsa_circ_0021735) and miR-502-5p. RNA pulldown and RIP assays were used to investigate the interaction between circCD44 and IGF2BP2. Cell viability, colony formation, migration/invasion assays and in vivo tumorigenesis were used to investigate circCD44 biological functions.

RESULTS

CircCD44 is an uncharacterized circRNA, which is highly expressed in TNBC, and its expression is negatively correlated with the prognosis of TNBC patients. CircCD44 promotes TNBC proliferation, migration, invasion and tumorigenesis at least partially by sponging miR-502-5p and interacting with IGF2BP2.

CONCLUSION

Our data suggested that overexpressed circCD44 promotes TNBC progression. CircCD44 is potentially a novel diagnostic and therapeutic marker for TNBC patients.

Circular RNAs in peripheral blood mononuclear cells from ankylosing spondylitis

BACKGROUND

Circular RNA (circRNA) is a type of closed circular noncoding RNA (ncRNA), mostly formed by back-splicing or alternative splicing of pre-messenger RNA (mRNA). The aim of this study was to explore the expression profile of circRNA in peripheral blood mononuclear cells (PBMCs) of patients with ankylosing spondylitis (AS) and discover potential molecular markers of AS.

METHODS

The circRNA microarray technology was used to detect the expression of circRNAs in the peripheral blood of 6 patients with AS and 6 healthy controls (HC). To screen the differentially expressed circRNAs by fold change (FC) and P value, these differentially expressed circRNAs were analyzed by bioinformatics. In 60 cases of AS and 30 cases of HC, 4 circRNAs were subjected to real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), and their correlation with various clinical indicators was analyzed. Finally, the receiver operating characteristic (ROC) curve was used to analyze their potential as AS diagnostic markers.

RESULTS

The microarray results showed that there were 1369 significantly differently expressed (P < 0.05, FC > 1.5) circRNAs between the AS and HC groups (675 upregulated and 694 downregulated). The results of bioinformatics analysis suggested that they were mainly involved in "enzyme binding," "adenosine ribonucleotide binding," "MAPK signaling pathway", etc. The RT-qPCR results showed that the expressions of hsa_circRNA_001544 (U = 486.5, P < 0.05) and hsa_circRNA_102532 (U = 645, P < 0.05) were significantly different between the AS group and the HC group. The AS group was further divided into two subgroups: active AS (ASA) and stable AS (ASS). After analysis, it was found that compared with the HC group, hsa_circRNA_001544 was significantly increased in both ASA (U = 214, P < 0.05) and ASS groups (U = 273, P < 0.05), while hsa_circRNA_008961 (U = 250, P < 0.05) and hsa_circRNA_102532 (U = 295, P < 0.05) were only significantly increased in the ASA group. Furthermore, hsa_circRNA_012732 was significantly different between the ASA and ASS groups (U = 194, P < 0.05), and there was no statistical significance among the remaining groups. Correlation analysis results showed that hsa_circRNA_012732 was negatively correlated with Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), high-sensitivity C-reactive protein (hsCRP), and globulin (GLOB) and positively correlated with lymphocyte count (LY), mean corpusular volume, and albumin (ALB), and hsa_circRNA_008961 was negatively correlated with platelet (PLT) count. ROC curve analysis showed that hsa_circRNA_001544 (95% CI = 0.610-0.831, P < 0.05) and hsa_circRNA_102532 (95% CI = 0.521-0.762, P < 0.05) were statistically significant, and their area under curve (AUC) values were 0.720 and 0.642, respectively.

CONCLUSIONS

There are differentially expressed circRNAs in PBMCs of AS patients, and they may be involved in the occurrence and development of AS. Among these differentially expressed circRNAs, hsa_circRNA_012732 has the potential to become an indicator of disease activity, and hsa_circRNA_001544 has the potential to become a molecular marker for AS diagnosis.

EFNA3 as a predictor of clinical prognosis and immune checkpoint therapy efficacy in patients with lung adenocarcinoma

BACKGROUND

Ephrin receptors (Eph) and their ligands, called ephrins, function in various disease processes. However, the expression level and prognostic value of Eph/ephrins in lung adenocarcinoma (LUAD) are still unclear.

METHODS

The Oncomine and GEPIA databases were used to explore the differential expression of Eph/ephrins in LUAD. Kaplan-Meier plotter was selected to explore the prognostic value of Eph/ephrins. The cBioPortal database was used to analyze the genetic variation of the EFNA3 gene. Immunohistochemistry was used to analyze the expression level and clinical value of ephrin-A3 protein in clinical LUAD tissue. Weighted coexpression network analysis (WGCNA) and gene set enrichment analysis (GSEA) identified the potential regulatory mechanism of EFNA3. CCK-8 assays and colony-forming experiments were used to investigate whether EFNA3 can regulate cell proliferation ability in LUAD. Analysis of lactate, ATP, and glucose uptake levels was used to explore the effect of EFNA3 on glycolysis ability. In addition, we investigated the relationship between EFNA3 and tumor infiltrating immune cells (TIICs). Finally, the potential immunotherapy response prediction value of EFNA3 was also explored.

RESULTS

In this study, we found that EFNA3 expression was significantly correlated with both overall survival (OS) and progression-free survival (PFS) in LUAD patients based on a comprehensive analysis of the Eph/Ephrin family. Next, the expression of the EFNA3 protein was increased in LUAD tissues and was designated an independent prognostic risk factor. Mechanistically, EFNA3 may be involved in nuclear division, synaptic function, and ion channel activity-related pathways. In vitro experiments confirmed the role of EFNA3 in promoting LUAD cells and showed that it could regulate glycolytic capacity. Moreover, EFNA3 was negatively associated with immunity, stromal infiltration, and several TIICs. Finally, EFNA3 was found to be positively related to multiple immunotherapy biomarkers.

CONCLUSIONS

In conclusion, increased EFNA3 in LUAD patients predicted worse clinical prognosis, promoted LUAD cell proliferation and glycolysis ability, and was related to immunotherapy response.

Improvement of cardiac function by mesenchymal stem cells derived extracellular vesicles through targeting miR-497/Smad7 axis

Background: The extracellular vesicles (EVs) secreted by bone marrow mesenchymal stromal cells (MSCs) have the ability to improve Myocardial infarction (MI). Some microRNAs (miRNAs) including miR-497 and related target genes have been proved to be closely linked with heart diseases. However, EVs could regulate MI process through miR-497, and the mechanisms have not been fully reported.

Methods: Ligation of left anterior descending artery was performed to established MI animals model. Hypoxia cell model was established through lowering the level of oxygen. The cell invasion, migration, and proliferation were measured using tanswell, wound heating, and MTT assays. HE, Masson trichrome, and Sirius Red staining were used to investigate the morphological changes.

Results: Overexpression of miR-497 reversed the promotion of cell migration, invasion, and proliferation caused by EVs. The improvement of cardiac function induced by EVs could also be reversed by overexpression of miR-497. Direct binding site between Smad7 and miR-497 was identified. Knockdown of Smad7 reversed the improvement of cardiac function induced by EVs.

Conclusions: We found that EVs isolated from MSCs might improve the cardiac injury caused by MI through targeting miR497/Smad7. This study provides novel potential therapeutic thought for the prevention and treatment of MI through targeting miR-497/Smad7.

Circular RNA hsa_circ_0007507 May Serve as a Biomarker for the Diagnosis and Prognosis of Gastric Cancer

PURPOSE

The morbidity and mortality of gastric cancer (GC) remain high worldwide. In recent years, circular RNAs (circRNAs) have attracted widespread attention among cancer researchers due to the stable ring structure. The present work aims to find serum circRNA biomarkers that can be used in clinical applications and effective diagnosis.

METHODS

Hsa_circ_0007507 was extracted through circRNA sequencing. Exonuclease digestion assay, actinomycin D, agarose gel electrophoresis (AGE), and Sanger sequencing verified the potential of hsa_circ_0007507 as a biomarker. Besides, a real-time fluorescent quantitative polymerase chain reaction (RT-qPCR) was established to detect the level of expression of hsa_circ_0007507. Twenty cases of GC and the paired adjacent tissues were collected to verify its overexpression. Then, serum samples from 30 cases of colorectal cancer, 30 cases of thyroid cancer, and 30 cases of breast cancer were collected to verify their organ specificity. Additionally, serum samples from 80 healthy people, 62 gastritis patients, 31 intestinal metaplasia patients, and 100 GC patients were collected, and the diagnostic efficacy was evaluated through analysis of the receiver operating characteristic (ROC) curve. Furthermore, 16 post-operative GC samples, samples of 65 relapsed patients and 36 non-relapsed patients were collected to evaluate the prognosis of GC.

RESULTS

The level of expression of hsa_circ_0007507 in GC tissues was up-regulated (p = 0.0121), which was consistent with the results of circRNA sequencing. Exonuclease digestion assay and actinomycin D confirmed that hsa_circ_0007507 had a stable structure and a longer half-life. In the analysis of organ specificity experiments, serum hsa_circ_0007507 did not have specificity for patients with colorectal cancer (p = 0.5319), thyroid cancer (p = 0.5422), or breast cancer (p = 0.5178). Analysis of diagnostic efficacy indicated that the expression of hsa_circ_0007507 was significantly higher than that of normal people (p <0.0001); the area under the ROC (AUC) was 0.832 (95% CI: 0.771-0.892); the diagnostic power of hsa_circ_0007507 was higher than that of CEA (AUC = 0.765, 95% CI: 0.697-0.833) and CA199 (AUC = 0.587, 95% CI: 0.504-0.67). Through diagnosis using a combination of the three, GC patients could be distinguished from normal people (AUC = 0.849), and higher diagnostic efficiency could be achieved. The expression of serum hsa_circ_0007507 in GC patients significantly decreased after surgery (p = 0.001). Besides, the expression of serum hsa_circ_0007507 in patients with post-operative recurrence was significantly up-regulated again (p = 0.0139).

CONCLUSIONS

Serum hsa_circ_0007507 is differentially expressed in GC patients, post-operative GC patients, gastritis patients, intestinal metaplasia patients and relapsed patients, suggesting that serum hsa_circ_0007507 can be used as a new diagnostic and dynamic monitoring biomarker for GC.

Identification of miRNA-target gene regulatory networks in liver fibrosis based on bioinformatics analysis

Background

Liver cirrhosis is one of the leading causes of death worldwide. MicroRNAs (miRNAs) can regulate liver fibrosis, but the underlying mechanisms are not fully understood, and the interactions between miRNAs and mRNAs are not clearly elucidated.

Methods

miRNA and mRNA expression arrays of cirrhotic samples and control samples were acquired from the Gene Expression Omnibus database. miRNA-mRNA integrated analysis, functional enrichment analysis and protein-protein interaction (PPI) network construction were performed to identify differentially expressed miRNAs (DEMs) and mRNAs (DEGs), miRNA-mRNA interaction networks, enriched pathways and hub genes. Finally, the results were validated with in vitro cell models.

Results

By bioinformatics analysis, we identified 13 DEMs between cirrhotic samples and control samples. Among these DEMs, six upregulated (hsa-miR-146b-5p, hsa-miR-150-5p, hsa-miR-224-3p, hsa-miR-3135b, hsa-miR-3195, and hsa-miR-4725-3p) and seven downregulated (hsa-miR-1234-3p, hsa-miR-30b-3p, hsa-miR-3162-3p, hsa-miR-548aj-3p, hsa-miR-548x-3p, hsa-miR-548z, and hsa-miR-890) miRNAs were further validated in activated LX2 cells. miRNA-mRNA interaction networks revealed a total of 361 miRNA-mRNA pairs between 13 miRNAs and 245 corresponding target genes. Moreover, PPI network analysis revealed the top 20 hub genes, including COL1A1, FBN1 and TIMP3, which were involved in extracellular matrix (ECM) organization; CCL5, CXCL9, CXCL12, LCK and CD24, which participated in the immune response; and CDH1, PECAM1, SELL and CAV1, which regulated cell adhesion. Functional enrichment analysis of all DEGs as well as hub genes showed similar results, as ECM-associated pathways, cell surface interaction and adhesion, and immune response were significantly enriched in both analyses.

Conclusions

We identified 13 differentially expressed miRNAs as potential biomarkers of liver cirrhosis. Moreover, we identified 361 regulatory pairs of miRNA-mRNA and 20 hub genes in liver cirrhosis, most of which were involved in collagen and ECM components, immune response, and cell adhesion. These results would provide novel mechanistic insights into the pathogenesis of liver cirrhosis and identify candidate targets for its treatment.

The Role of miR-155 in Nutrition: Modulating Cancer-Associated Inflammation

Nutrition plays an important role in overall human health. Although there is no direct evidence supporting the direct involvement of nutrition in curing disease, for some diseases, good nutrition contributes to disease prevention and our overall well-being, including energy level, optimum internal function, and strength of the immune system. Lately, other major, but more silent players are reported to participate in the body’s response to ingested nutrients, as they are involved in different physiological and pathological processes. Furthermore, the genetic profile of an individual is highly critical in regulating these processes and their interactions. In particular, miR-155, a non-coding microRNA, is reported to be highly correlated with such nutritional processes. In fact, miR-155 is involved in the orchestration of various biological processes such as cellular signaling, immune regulation, metabolism, nutritional responses, inflammation, and carcinogenesis. Thus, this review aims to highlight those critical aspects of the influence of dietary components on gene expression, primarily on miR-155 and its role in modulating cancer-associated processes.

MicroRNA Sequences Modulated by Beta Cell Lipid Metabolism: Implications for Type 2 Diabetes Mellitus

Alterations in lipid metabolism within beta cells and islets contributes to dysfunction and apoptosis of beta cells, leading to loss of insulin secretion and the onset of type 2 diabetes. Over the last decade, there has been an explosion of interest in understanding the landscape of gene expression which influences beta cell function, including the importance of small non-coding microRNA sequences in this context. This review sought to identify the microRNA sequences regulated by metabolic challenges in beta cells and islets, their targets, highlight their function and assess their possible relevance as biomarkers of disease progression in diabetic individuals. Predictive analysis was used to explore networks of genes targeted by these microRNA sequences, which may offer new therapeutic strategies to protect beta cell function and delay the onset of type 2 diabetes.

LncRNA PCA3 promotes antimony-induced lipid metabolic disorder in prostate cancer by targeting MIR-132-3 P/SREBP1 signaling

Antimony is a common environmental contaminant that causes biological toxicity in exposed populations worldwide. Previous studies have revealed that antimony promotes prostate cancer growth by stabilizing the c-Myc protein and mimicking androgen activity. However, the role of lncRNAs in the regulation of antimony-induced carcinogenesis remains unknown, and the precise mechanisms need to be explored. In the present study, we found that chronic exposure to antimony promoted cell growth and lipid metabolic disequilibrium in prostate cancer. Mechanistically, we identified a long noncoding RNA molecule, PCA3, that was substantially upregulated in LNCaP cells in response to long-term antimony exposure. Functional studies indicated that abnormal PCA3 expression modulated antimony-induced proliferation and cellular triglyceride and cholesterol levels. In addition, PCA3 levels were found to be inversely correlated with MIR-132-3 P levels by acting as a decoy for MIR-132-3P. Besides, SREBP1 directly interacted with MIR-132-3 P to increase cell growth and disrupt lipid metabolism by targeting its 3'UTR regions. Taken together, our results revealed that lncRNA PCA3 promotes antimony-induced lipid metabolic disorder in prostate cancer by targeting MIR-132-3 P/SREBP1 signaling.