MiR‐182‐5p inhibited oxidative stress and apoptosis triggered by oxidized low‐density lipoprotein via targeting toll‐like receptor 4

Fostering tissue engineering and regenerative medicine to treat musculoskeletal disorders in bone and muscle

The musculoskeletal system, which is vital for movement, support, and protection, can be impaired by disorders such as osteoporosis, osteoarthritis, and muscular dystrophy. This review focuses on the advances in tissue engineering and regenerative medicine, specifically aimed at alleviating these disorders. It explores the roles of cell therapy, particularly Mesenchymal Stem Cells (MSCs) and Adipose-Derived Stem Cells (ADSCs), biomaterials, and biomolecules/external stimulations in fostering bone and muscle regeneration. The current research underscores the potential of MSCs and ADSCs despite the persistent challenges of cell scarcity, inconsistent outcomes, and safety concerns. Moreover, integrating exogenous materials such as scaffolds and external stimuli like electrical stimulation and growth factors shows promise in enhancing musculoskeletal regeneration. This review emphasizes the need for comprehensive studies and adopting innovative techniques together to refine and advance these multi-therapeutic strategies, ultimately benefiting patients with musculoskeletal disorders.

Comprehensive analysis of the differential expression of mRNAs, lncRNAs, and miRNAs in Zi goose testis with high and low sperm mobility

Sperm mobility (SM) is an objective index for measuring sperm motility; however, the mechanisms underlying its regulation in geese remain unclear. The present study sought to elucidate the genetic mechanism underlying SM traits in Zi geese (Anser cygnoides L.). To this end, three successive experiments were performed. In Experiment I, SM was determined in 40 ganders; the 3 ganders with the highest mobility and three with the lowest mobility were assigned to the high and low sperm mobility rank (SMR) groups, respectively. In Experiment II, the differences in fertility between the two SMR groups were assessed within two breeding flocks comprising the selected six ganders from Experiment I and 30 females (each flock had 3 ganders and 15 females). In Experiment III, the testes of the 6 ganders were harvested for histological observation and whole-transcriptome sequencing. Results revealed better fertility, well-developed seminiferous tubules, and abundant mature sperm in the high-SMR-flock compared to those of the low-SMR-flock (89 vs. 81%) (P < 0.05). Differential expression (DE) analysis identified 76 mRNAs, 344 lncRNAs, and 17 miRNAs between the SMR groups, with LOC106049708, XPNPEP3, GNB3, ADCY8, PRKAG3, oha-miR-182-5p, and ocu-miR-10b-5p identified as key mRNAs and miRNAs contributing to SM. Enrichment analysis implicated these DE RNAs in pathways related to ATP binding, cell metabolism, apelin signaling, Wnt signaling, and Adherens junctions. Additionally, competing endogenous RNA (ceRNA) networks comprising 9 DE mRNAs, 17 DE miRNAs, and 169 DE lncRNAs were constructed. Two ceRNA network pathways (LOC106049708-oha-miR-182-5p-MSTRG.2479.6 and PRKAG3-ocu-miR-10b-5p-MSTRG.9047.14) were identified as key regulators of SM in geese. These findings offer crucial insights into the identification of key genes and ceRNA pathways influencing sperm mobility in geese.

Extracellular vesicles in the treatment of oxidative stress injury: global research status and trends

Objective: The aim of this study was to conduct a bibliometric analysis of the literature on "Extracellular Vesicles in the Treatment of Oxidative Stress Injury" and to reveal its current status, hot spots and trends. Methods: The relevant literature was obtained from the Web of Science Core Collection (WoSCC) on 29 April 2023. We performed clustering and partnership analysis of authors, institutions, countries, references and keywords in the literature through CiteSpace software and the bibliometric online analysis platform and mapped the relevant knowledge maps. Results: A total of 1,321 relevant publications were included in the bibliometric analysis, with the number of publications in this field increasing year by year. These included 944 "articles" and 377 "reviews". The maximum number of publications published in China is 512, and the maximum number of highly cited publications published in the United States is 20. Based on CiteSpace, the country collaboration network map shows close and stable collaboration among high-productivity countries. Based on WoSCC, there are 1706 relevant research institutions and 119 highly cited elite institutions, among which Kaohsing Chang Gung Men Hosp has the most extensive influence. Studies related to "Extracellular Vesicles in the Treatment of Oxidative Stress Injury" have been published in 548 journals. The keywords of the publications show the main research areas and breakthroughs. Based on WoSCC, the keywords of the research area "Extracellular Vesicles in the Treatment of Oxidative Stress Injury" were found to be as follows: exosome(s), extracellular vesicle(s), oxidative stress, inflammation, mesenchymal stem cells, apoptosis, microRNA (miRNA), mitochondria, biomarker, autophagy, angiogenesis and Alzheimer's disease. Analysis showed that "mesenchymal stem cells", "microRNA", "autophagy", "histology" and "therapeutic" emerged as highly explosive keywords. Conclusion: This study is the first to use visual software and data mining to assess the literature in the field of "Extracellular Vesicles in the Treatment of Oxidative Stress Injury". The research history, research status and direction in this field provide a theoretical basis for its scientific research.

Advances in the study of exosomes in cardiovascular diseases

BACKGROUND

Cardiovascular disease (CVD) has been the leading cause of death worldwide for many years. In recent years, exosomes have gained extensive attention in the cardiovascular system due to their excellent biocompatibility. Studies have extensively researched miRNAs in exosomes and found that they play critical roles in various physiological and pathological processes in the cardiovascular system. These processes include promoting or inhibiting inflammatory responses, promoting angiogenesis, participating in cell proliferation and migration, and promoting pathological progression such as fibrosis.

AIM OF REVIEW

This systematic review examines the role of exosomes in various cardiovascular diseases such as atherosclerosis, myocardial infarction, ischemia-reperfusion injury, heart failure and cardiomyopathy. It also presents the latest treatment and prevention methods utilizing exosomes. The study aims to provide new insights and approaches for preventing and treating cardiovascular diseases by exploring the relationship between exosomes and these conditions. Furthermore, the review emphasizes the potential clinical use of exosomes as biomarkers for diagnosing cardiovascular diseases.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Exosomes are nanoscale vesicles surrounded by lipid bilayers that are secreted by most cells in the body. They are heterogeneous, varying in size and composition, with a diameter typically ranging from 40 to 160 nm. Exosomes serve as a means of information communication between cells, carrying various biologically active substances, including lipids, proteins, and small RNAs such as miRNAs and lncRNAs. As a result, they participate in both physiological and pathological processes within the body.

Childhood obesity, metabolic syndrome, and oxidative stress: microRNAs go on stage

The incidence of childhood obesity and metabolic syndrome has grown notably in the last years, becoming major public health burdens in developed countries. Nowadays, oxidative stress is well-recognized to be closely associated with the onset and progression of several obesity-related complications within the framework of a complex crosstalk involving other intertwined pathogenic events, such as inflammation, insulin disturbances, and dyslipidemia. Thus, understanding the molecular basis behind these oxidative dysregulations could provide new approaches for the diagnosis, prevention, and treatment of childhood obesity and associated disorders. In this respect, the transcriptomic characterization of miRNAs bares great potential because of their involvement in post-transcriptional modulation of genetic expression. Herein, we provide a comprehensive literature revision gathering state-of-the-art research into the association between childhood obesity, metabolic syndrome, and miRNAs. We put special emphasis on the potential role of miRNAs in modulating obesity-related pathogenic events, with particular focus on oxidative stress.

Research progress of extracellular vesicles and exosomes derived from mesenchymal stem cells in the treatment of oxidative stress-related diseases

There is growing evidence that mesenchymal stem cell-derived extracellular vesicles and exosomes can significantly improve the curative effect of oxidative stress-related diseases. Mesenchymal stem cell extracellular vesicles and exosomes (MSC-EVs and MSC-Exos) are rich in bioactive molecules and have many biological regulatory functions. In this review, we describe how MSC-EVs and MSC-Exos reduce the related markers of oxidative stress and inflammation in various systemic diseases, and the molecular mechanism of MSC-EVs and MSC-Exos in treating apoptosis and vascular injury induced by oxidative stress. The results of a large number of experimental studies have shown that both local and systemic administration can effectively inhibit the oxidative stress response in diseases and promote the survival and regeneration of damaged parenchymal cells. The mRNA and miRNAs in MSC-EVs and MSC-Exos are the most important bioactive molecules in disease treatment, which can inhibit the apoptosis, necrosis and oxidative stress of lung, heart, kidney, liver, bone, skin and other cells, and promote their survive and regenerate.

NLRP3 inflammasome pathway in atherosclerosis: Focusing on the therapeutic potential of non-coding RNAs

NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) inflammasome pathway has a critical role in the pathogenesis of atherosclerosis. Activation of this pathway is implicated in the subendothelial inflammation and atherosclerosis progression. The NLRP3 inflammasome are cytoplasmic sensors with the distinct capacity to identify a wide range of inflammation-related signals, which enhance NLRP3 inflammasome assembly and allow it to trigger inflammation. This pathway is triggered by a variety of intrinsic signals which exist in atherosclerotic plaques, like cholesterol crystals and oxidized LDL. Further pharmacological findings indicated that NLRP3 inflammasome enhanced caspase-1-mediated secretion of pro-inflammatory mediators like interleukin (IL)- 1β/18. Newly published cutting-edge studies suggested that non-coding RNAs (ncRNAs) including microRNAs (miRNAs, miRs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs) are major modulators of NLRP3 inflammasome in atherosclerosis. Therefore, in this review, we aimed to discuss the NLRP3 inflammasome pathway, biogenesis of ncRNAs as well as the modulatory role of ncRNAs in regulating the various mediators of NLRP3 inflammasome pathway including TLR4, NF-kB, NLRP3, and caspase 1. We also discussed the importance of NLRP3 inflammasome pathway-related ncRNAs as a diagnostic biomarker in atherosclerosis and current therapeutics in the modulation of NLRP3 inflammasome in atherosclerosis. Finally, we speak about the limitations and future prospects of ncRNAs in regulating inflammatory atherosclerosis via the NLRP3 inflammasome pathway.

The emerging crosstalk between atherosclerosis-related microRNAs and Bermuda triangle of foam cells: Cholesterol influx, trafficking, and efflux

In atherosclerosis, the gradual buildup of lipid particles into the sub-endothelium of damaged arteries leads to numerous lipid alterations. The absorption of these modified lipids by monocyte-derived macrophages in the arterial wall leads to cholesterol accumulation and increases the likelihood of foam cell formation and fatty streak, which is an early characteristic of atherosclerosis. Foam cell formation is related to an imbalance in cholesterol influx, trafficking, and efflux. The formation of foam cells is heavily regulated by various mechanisms, among them, the role of epigenetic factors like microRNA alteration in the formation of foam cells has been well studied. Recent studies have focused on the potential interplay between microRNAs and foam cell formation in the pathogenesis of atherosclerosis; nevertheless, there is significant space to progress in this attractive field. This review has focused to examine the underlying processes of foam cell formation and microRNA crosstalk to provide a deep insight into therapeutic implications in atherosclerosis.

Functions and therapeutic interventions of non-coding RNAs associated with TLR signaling pathway in atherosclerosis

Nowadays, emerging data demonstrate that the toll-like receptor (TLR) signaling pathway plays an important role in the progression of inflammatory atherosclerosis. Indeed, dysregulated TLR signaling pathway could be a cornerstone of inflammation and atherosclerosis, which contributes to the development of cardiovascular diseases. It is interesting to note that this pathway is heavily controlled by several mechanisms, such as epigenetic factors in which the role of non-coding RNAs (ncRNAs), particularly microRNAs and long noncoding RNAs as well as circular RNAs in the pathogenesis of atherosclerosis has been well studied. Recent years have seen a significant surge in the amount of research exploring the interplay between ncRNAs and TLR signaling pathway downstream targets in the development of atherosclerosis; however, there is still considerable room for improvement in this field. The current study was designed to review underlying mechanisms of TLR signaling pathway and ncRNA interactions to shed light on therapeutic implications in patients with atherosclerosis.

Feline microRNAome in ovary and testis: Exploration of in-silico miRNA-mRNA networks involved in gonadal function and cellular stress response

The aim of the study was to perform the first in-depth analysis of miRNAs in ovarian and testicular tissues of the domestic cat, a critical biomedical model. Specifically, potential miRNA involvement was explored in gonadal function, testis development, and cellular stress response to preservation protocols. We performed miRNA-sequencing on 20 ovarian and 20 testicular samples from 15 cats, including different ages and tissue treatments. Using fresh tissues (n = 15), we confirmed gonadal expression of 183 miRNA precursors and discovered additional 52 novel feline candidate precursors. We integrated the mRNA data from our previous study on the same age and treatment groups to create in-silico miRNA-mRNA networks and their functional enrichment, which allows comprehensive exploration into possible miRNA functions in cat gonads. Clusters of miRNAs united by shared differentially expressed mRNA targets are potentially involved in testicular development and spermatogenesis. MicroRNAs could play a significant role in ovarian tissue response to stress from microwave-assisted dehydration, with smaller roles in cellular response to vitrification in both ovary and testis. This new list of miRNAs with potential function in cat gonads is a major step towards understanding the gonadal biology, as well as optimizing fertility preservation protocols.

Hypoxia-induced miR-182-5p regulates vascular smooth muscle cell phenotypic switch by targeting RGS5

In response to vascular injury or alterations in the local environment, such as hypoxia and hypertension, contractile vascular smooth muscle cells (VSMCs) are able to switch to a synthetic phenotype characterized by increased extracellular matrix synthesis with decreased expression of contractile markers. miR-182-5p has recently been reported to play a regulatory role in VSMCs proliferation. However, little is known about its target genes and related pathways in VSMCs phenotypic switch. Here, we investigated the function of miR-182-5p in VSMCs phenotypic switch. The results showed that upregulation of miR-182-5p promoted the switching of VSMCs from a contractile to a synthetic phenotype under hypoxic conditions. Mechanistically, hypoxia elevated miR-182-5p, leading to a reduction in expression of contractile markers and weakened RhoA signaling. Using bioinformatics analysis, dual-luciferase reporter assays and rescue assays, we demonstrated that miR-182-5p suppressed RhoA signaling by targeting RGS5. Collectively, the results from the present study indicated that miR-182-5p/RGS5/RhoA axis regulated hypoxia-induced VSMCs phenotypic switch.

PCSK9 Modulates Macrophage Polarization-Mediated Ventricular Remodeling after Myocardial Infarction

Background and Aims

An increasing number of high-risk patients with coronary heart disease (similar to acute myocardial infarction (AMI)) are using PCSK9 inhibitors. However, whether PCSK9 affects myocardial repair and the molecular mechanism of PCSK9 modulation of immune inflammation after AMI are not known. The present research investigated the role of PCSK9 in the immunomodulation of macrophages after AMI and provided evidence for the clinical application of PCSK9 inhibitors after AMI to improve cardiac repair.

Methods and Results

Wild-type C57BL6/J (WT) and PCSK9^−/− mouse hearts were subjected to left anterior descending (LAD) coronary artery occlusion to establish an AMI model. Correlation analysis showed that higher PCSK9 expression indicated worse cardiac function after AMI, and PCSK9 knockout reduced infarct size, improved cardiac function, and attenuated inflammatory cell infiltration compared to WT mice. Notably, the curative effects of PCSK9 inhibition were abolished after the systemic depletion of macrophages using clodronate liposomes. PCSK9 showed a regulatory effect on macrophage polarization in vivo and in vitro. Our studies also revealed that activation of the TLR4/MyD88/NF-κB axis was a possible mechanism of PCSK9 regulation of macrophage polarization.

Conclusion

Our data suggested that PCSK9 modulated macrophage polarization-mediated ventricular remodeling after myocardial infarction.

LINC00092 Modulates Oxidative Stress and Glycolysis of Breast Cancer Cells via Pyruvate Carboxylase-Mediated AKT/mTOR Pathway

Background

The discovery of noncoding RNAs (ncRNAs) offers new options for cancer-targeted therapy. This study is aimed at exploring the regulatory function of LINC00092 on breast cancer (BC) oxidative stress and glycolysis, along with internal mechanism concerning pyruvate carboxylase (PC).

Methods

Bioinformatics analysis was used to explore LINC00092 (or friend leukemia virus integration 1 (FLI1)) expression on BC progression, as well as oxidative stress and glycolysis in BC. After LINC00092 overexpression or silence, BC cell viability, proliferation, migration, invasion, oxidative stress, glycolysis, and AKT/mTOR pathway were detected. Following 2-DG, SC79, or MK2206 treatment, effects of LINC00092 on BC cells were measured. Moreover, regulatory activity of LINC00092 in PC expression was analyzed. Whether PC participated in the modulation of LINC00092 on BC cell functions was explored.

Results

LINC00092 was lowly expressed in BC and negatively related to BC progression. FLI1 bound to LINC00092 promoter to positively modulate LINC00092. LINC00092 overexpression inhibited BC cell proliferation, migration, invasion, oxidative stress, glycolysis, and AKT/mTOR pathway and likewise suppressed BC growth in vivo. Silence of LINC00092 had opposite influences. 2-DG partially reversed the LINC00092 silence-resulted increase of BC cell proliferation. SC79 alleviated the function of LINC00092 overexpression on BC cell functions. MK2206 had the contrary influence of SC79. Besides, LINC00092 bound to PC to modulate ubiquitination degradation of PC protein. PC took part in the influences of LINC00092 on BC cell functions.

Conclusions

LINC0092 modulates oxidative stress and glycolysis of BC cells via the PC-mediated AKT/mTOR pathway, which is possibly a target for BC diagnosis and therapy.

Role and mechanism of circular RNA circ_0050486 in regulating oxidized low-density lipoprotein-induced injury in endothelial cells

BACKGROUND

Dysfunction of endothelial cells in the arterial vasculature is an essential contributor to the pathogenesis of atherosclerosis. Circular RNAs (circRNAs) exert important regulatory functions in endothelial cell dysfunction. Here, we explored the precise role and mechanism of circ_0050486 in regulating endothelial cell injury induced by oxidized low-density lipoprotein (ox-LDL).

METHODS

Circ_0050486, microRNA (miR)-182-5p and myeloid differentiation primary response gene 88 (MyD88) were quantified by quantitative real-time PCR or western blot. Cell viability, proliferation and apoptosis were examined by MTS, 5-Ethynyl-2'-Deoxyuridine (EdU), and flow cytometry assays, respectively. Direct relationship between miR-182-5p and circ_0050486 or MYD88 was verified by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays.

RESULTS

Circ_0050486 was upregulated in atherosclerosis serum and ox-LDL-treated human aortic endothelial cells (HAECs). Silencing of circ_0050486 suppressed HAEC injury induced by ox-LDL. Mechanistically, circ_0050486 targeted miR-182-5p, and the effects of circ_0050486 silencing were partially due to the upregulation of miR-182-5p. MYD88 was a direct target of miR-182-5p, and miR-182-5p-mediated inhibition of MYD88 attenuated ox-LDL-evoked HAEC injury. Circ_0050486 bound to miR-182-5p to regulate MYD88 expression. Additionally, the NF-κB signaling pathway was involved in the regulation of circ_0050486/miR-182-5p/MYD88 axis in ox-LDL-treated HAECs.

CONCLUSION

Our study identifies the functional role of circ_0050486 in ox-LDL-induced endogenous cell injury and establishes a mechanism of circ_0050486 function by affecting MYD88 through competitively binding to shared miR-182-5p.

Extracellular Vesicle/Macrophage Axis: Potential Targets for Inflammatory Disease Intervention

Extracellular vesicles (EVs) can regulate the polarization of macrophages in a variety of inflammatory diseases by mediating intercellular signal transduction and affecting the occurrence and development of diseases. After macrophages are regulated by EVs, they mainly show two phenotypes: the proinflammatory M1 type and the anti-inflammatory M2 type. A large number of studies have shown that in diseases such as mastitis, inflammatory bowel disease, Acute lung injury, and idiopathic pulmonary fibrosis, EVs promote the progression of the disease by inducing the M1-like polarization of macrophages. In diseases such as liver injury, asthma, and myocardial infarction, EVs can induce M2-like polarization of macrophages, inhibit the inflammatory response, and reduce the severity of the disease, thus indicating new pathways for treating inflammatory diseases. The EV/macrophage axis has become a potential target for inflammatory disease pathogenesis and comprehensive treatment. This article reviews the structure and function of the EV/macrophage axis and summarizes its biological functions in inflammatory diseases to provide insights for the diagnosis and treatment of inflammatory diseases.

CD36, a signaling receptor and fatty acid transporter that regulates immune cell metabolism and fate

CD36 is a type 2 cell surface scavenger receptor widely expressed in many immune and non-immune cells. It functions as both a signaling receptor responding to DAMPs and PAMPs, as well as a long chain free fatty acid transporter. Recent studies have indicated that CD36 can integrate cell signaling and metabolic pathways through its dual functions and thereby influence immune cell differentiation and activation, and ultimately help determine cell fate. Its expression along with its dual functions in both innate and adaptive immune cells contribute to pathogenesis of common diseases, including atherosclerosis and tumor progression, which makes CD36 and its downstream effectors potential therapeutic targets. This review comprehensively examines the dual functions of CD36 in a variety of immune cells, especially macrophages and T cells. We also briefly discuss CD36 function in non-immune cells, such as adipocytes and platelets, which impact the immune system via intercellular communication. Finally, outstanding questions in this field are provided for potential directions of future studies.

MicroRNA-182-5p Attenuates Asthmatic Airway Inflammation by Targeting NOX4

Bronchial asthma is characterized by chronic airway inflammation, airway hyperresponsiveness, and airway remodeling. MicroRNA (miRNA) has recently been implicated in the pathogenesis of asthma. However, the mechanisms of different miRNAs in asthma are complicated, and the mechanism of miRNA-182-5p in asthma is still unclear. Here, we aim to explore the mechanism of miRNA182-5p in asthma-related airway inflammation. Ovalbumin (OVA)-induced asthma model was established. MiRNA Microarray Analysis was performed to analyze the differentially expressed miRNAs in the asthma model. We found that the expression of miRNA-182-5p was significantly decreased in OVA-induced asthma. In vitro, IL-13 stimulation of BEAS-2B cells resulted in a significant up-regulation of NOX4 (nicotinamide adenine dinucleotide phosphate oxidase 4), accompanied by mitochondrial damage-induced apoptosis, NLRP3 (NOD-like receptor family pyrin domain-containing 3)/IL-1β activation, and reduced miRNA-182-5p. In contrast, overexpression of miRNA-182-5p significantly inhibited epithelial cell apoptosis and NLRP3/IL-1β activation. In addition, we found that miRNA-182-5p could bind to the 3’ untranscripted region of NOX4 mRNA and inhibit epithelial cell inflammation by reducing oxidative stress and mitochondrial damage. In vivo, miRNA-182-5p agomir treatment significantly reduced the percentage of eosinophils in bronchoalveolar lavage fluid, and down-regulated Th2 inflammatory factors, including IL-4, IL-5, and OVA induced IL-13. Meanwhile, miRNA-182-5p agomir reduced the peribronchial inflammatory cell infiltration, goblet cell proliferation and collagen deposition. In summary, targeting miRNA-182-5p may provide a new strategy for the treatment of asthma.

Mesenchymal stem cell-derived exosomal microRNA-182-5p alleviates myocardial ischemia/reperfusion injury by targeting GSDMD in mice

Recent evidence indicates that exosomes derived from mesenchymal stem cells (MSCs) confer protective effects against myocardial ischemia/reperfusion (I/R) injury. Exosomes are carriers of potentially protective endogenous molecules, including microRNAs (miRNAs/miRs). The current study set out to test the effects of transferring miR-182-5p from MSC-derived exosomes into myocardial cells on myocardial I/R injury. First, an I/R mouse model was developed by left anterior descending coronary artery occlusion, and myocardial cells were exposed to hypoxia/reoxygenation (H/R) for in vitro I/R model establishment. Loss- and gain-of-function experiments of miR-182-5p and GSDMD were conducted to explore the effects of miR-182-5p via MSC-derived exosomes on cell pyroptosis and viability. GSDMD was robustly expressed in I/R-injured myocardial tissues and H/R-exposed myocardial cells. GSDMD upregulation promoted H/R-induced myocardial cell pyroptosis and reduced viability, corresponding to increased lactate dehydrogenase release, reactive oxygen species production, and pyroptosis. A luciferase assay demonstrated GSDMD as a target of miR-182-5p. In addition, exosomal miR-182-5p was found to diminish GSDMD-dependent cell pyroptosis and inflammation induced by H/R. Furthermore, MSC-derived exosomes carrying miR-182-5p improved cardiac function and reduced myocardial infarction, accompanied with reduced inflammation and cell pyroptosis in vivo. Taken together, our findings suggest a cardioprotective effect of exosomal miR-182-5p against myocardial I/R injury, shedding light on an attractive therapeutic strategy.

Relationships between Indicators of Lower Extremity Artery Disease and miRNA Expression in Peripheral Blood Mononuclear Cells

Lower extremity artery disease (LEAD) is an underdiagnosed and globally underestimated vascular disease caused by the progressive and chronic formation of atherosclerotic plaques in the arteries of the lower limbs. Much evidence indicates that the abnormal course of pathophysiological processes underlying LEAD development is associated with altered miRNA modulatory function. In the presented study, relationships between miRNA expression and clinical indicators of this disease (ABI, claudication distance, length of arterial occlusion, Rutherford category, and plaque localization) were identified. MiRNA expression profiles were obtained using next-generation sequencing in peripheral blood mononuclear cells (PBMCs) of 40 LEAD patients. Correlation analysis performed using the Spearman rank correlation test revealed miRNAs related to ABI, claudication distance, and length of arterial occlusion. In the DESeq2 analysis, five miRNAs were found to be dysregulated in patients with Rutherford category 3 compared to patients with Rutherford category 2. No miRNAs were found to be differentially expressed between patients with different plaque localizations. Functional analysis performed using the miRNet 2.0 website tool determined associations of selected miRNAs with processes underlying vascular pathology, such as vascular smooth muscle cell differentiation, endothelial cell apoptosis, response to hypoxia, inflammation, lipid metabolism, and circadian rhythm. The most enriched functional terms for genes targeted by associated miRNAs were linked to regulation of the cell cycle, regulation of the transcription process, and nuclear cellular compartment. In conclusion, dysregulations of miRNA expression in PBMCs of patients with LEAD are indicative of the disease and could potentially be used in the prediction of LEAD progression.

MicroRNA-223-3p inhibits oxidized low-density lipoprotein-mediated NLRP3 inflammasome activation via directly targeting NLRP3 and FOXO3

BACKGROUND

MicroRNAs (miRNAs) have emerged as crucial players in the initiation and development of atherosclerosis (AS), and the low miR-223-3p level is observed in AS patients. However, the function and mechanism behind miR-223-3p in AS progression have not been fully elucidated.

METHOD

In the present study, THP-1 cells treated with oxidized low-density lipoprotein (ox-LDL) were employed as the cell model of AS. The expression levels of miR-223-3p, NLR family pyrin domain containing 3 (NLRP3), caspase-1, pro-caspase-1, cleaved interleukin 18 (IL-18), cleaved IL-1β, and forkhead box O3 (FOXO3) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot (WB) analyses. The relationship between miR-223-3p and FOXO3 or NLRP3 was determined using a dual-luciferase reporter assay. The production of IL-1β, IL-18, IL-6, and TNF-α was examined by Enzyme-linked immunosorbent assay (ELISA).

RESULTS

MiR-223-3p was decreased in AS patients and ox-LDL-induced THP-1 cells, and its upregulation downregulated the abundance of NLRP3, caspase-1, cleaved IL-18, cleaved IL-1β, IL-1β, IL-6, and TNF-α in THP-1 cells treated with ox-LDL or not, and the depletion of miR-223-3p revealed an opposite phenomenon. NLPR3 and FOXO3 were identified as two authentic targets of miR-223-3p. Knockdown of NLRP3 or FOXO3 reversed the stimulatory effect of the miR-223-3p inhibitor on the inflammatory responses of THP-1 cells.

CONCLUSIONS

Our data indicate that miR-223-3p inhibited ox-LDL-mediated NLRP3 inflammasome activation via directly targeting NLRP3 and FOXO3 in THP-1 cells, which offered a prospective therapeutic target for AS therapy.

Circular RNA HECTD1 Mitigates Ulcerative Colitis by Promoting Enterocyte Autophagy Via miR-182-5p/HuR Axis

OBJECTIVE

Ulcerative colitis (UC) is a chronic colitis with unknown etiology. Circular RNA (circRNA) has shown regulatory effect in many diseases, but the role of circRNA in UC is barely known. This study uncovers the function and regulatory mechanism of circRNA HECTD1 (circHECTD1) in UC.

METHODS

Colonic mucosal tissues of 60 patients with active UC and 30 healthy controls were collected for H&E staining. Lipopolysaccharide (LPS) and dextran sulfate sodium (DSS) were used to induce inflammation and UC in Caco-2 cells and C57BL/6 mice where modification of circHECTD1, miR-182-5p and/or human antigen R (HuR) took place. The Caco-2 cells and the colon tissues of DSS-treated mice were collected for analysis of the expression levels of inflammatory cytokines, NLRP3 inflammasome, and autophagy-related proteins. The interactions among circHECTD1, miR-182-5p, and HuR were verified.

RESULTS

The colonic mucosal tissues of UC patients showed impaired autophagy and decreased expressions of circHECTD1 and HuR. Overexpression of circHECTD1 or HuR or inhibition of miR-182-5p suppressed inflammation and promoted autophagy of LPS-induced Caco-2 cells. The expression of HuR was promoted by circHECTD1 via miR-182-5p in Caco-2 cells. Overexpression of circHECTD1 reduced colonic injuries and inflammation by promoting autophagy in DSS-treated mice.

CONCLUSION

Overexpression of circHECTD1 alleviates UC by promoting HuR-dependent autophagy via miR-182-5p. This study highlights the therapeutic potential of circHECTD1 for UC and adds to the knowledge of circRNA in the pathogenesis of UC.

MiR-182-5p/TLR4/NF-κB axis contributes to the protective effect of caffeic acid phenethyl ester against cadmium-induced spleen toxicity and associated damage in mice

Cadmium (Cd) is a toxic heavy metal pollutant that can be accumulated in organs including the spleen, thereby threatening human health. In this study, the effect of caffeic acid phenethyl ester (CAPE, a bioactive component of honeybee propolis) on CdCl2-induced spleen toxicity and underlying mechanisms were examined in mice. Histological examinations revealed that CAPE (10 μmol/kg/day b.w.) could mitigate spleen damage induced by CdCl2 (1.5 mg/kg/day b.w.) in mice. Compared to the mice treated only by CdCl2, CAPE administration increased the body weight while decreasing the spleen weight, spleen Cd content and spleen to body ratio of the CdCl2-treated mice. Western blot and ELISA tests revealed that CAPE suppressed CdCl2-induced inflammation (indicated by the decreases in the levels of inflammatory indictors). TUNEL and Western blot results showed that CAPE suppressed CdCl2-induced apoptosis through reducing the percentage of TUNEL-positive cells and regulating apoptosis factors. The antagonistic effect of CAPE against CdCl2-induced spleen toxicity was realized by increasing miR-182-5p expression to regulate the TLR4/NF-κB pathway. Therefore, CAPE could be a food-derived spleen protector to counteract Cd-induced spleen toxicity through alleviating apoptosis and inflammation via the miR-182-5p/TLR4/NF-κB axis.

OncomiR miR-182-5p Enhances Radiosensitivity by Inhibiting the Radiation-Induced Antioxidant Effect through SESN2 in Head and Neck Cancer

Radiotherapy is routinely used for the treatment of head and neck squamous cell carcinoma (HNSCC). However, the therapeutic efficacy is usually reduced by acquired radioresistance and locoregional recurrence. In this study, The Cancer Genome Atlas (TCGA) analysis showed that radiotherapy upregulated the miR-182/96/183 cluster and that miR-182 was the most significantly upregulated. Overexpression of miR-182-5p enhanced the radiosensitivity of HNSCC cells by increasing intracellular reactive oxygen species (ROS) levels, suggesting that expression of the miR-182 family is beneficial for radiotherapy. By intersecting the gene targeting results from three microRNA target prediction databases, we noticed that sestrin2 (SESN2), a molecule resistant to oxidative stress, was involved in 91 genes predicted in all three databases to be directly recognized by miR-182-5p. Knockdown of SESN2 enhanced radiation-induced ROS and cytotoxicity in HNSCC cells. In addition, the radiation-induced expression of SESN2 was repressed by overexpression of miR-182-5p. Reciprocal expression of the miR-182-5p and SESN2 genes was also analyzed in the TCGA database, and a high expression of miR-182-5p combined with a low expression of SESN2 was associated with a better survival rate in patients receiving radiotherapy. Taken together, the current data suggest that miR-182-5p may regulate radiation-induced antioxidant effects and mediate the efficacy of radiotherapy.

MiRNA-182-5p aggravates experimental ulcerative colitis via sponging Claudin-2

Tight junction proteins play crucial roles in maintaining the integrity of intestinal mucosal barrier. MiRNA-182-5p is capable of targeting claudin-2 which is one of the vital tight junction proteins and the effect and mechanism of miRNA-182-5p was explored here in the DSS-induced colitis model. The pathological conditions were evaluated via hematoxylin and eosin staining. The gene expression level was assessed via PCR. Quantitative immunohistochemistry analysis was performed for the measurement of claudin-2. microRNA.org online tool was used for target gene prediction. Luciferase reporter assay and RNA pull-down assay were performed to detect the target of miRNA-182-5p. The inflammatory and oxidative stress level were measured using corresponding kits. MiRNA-182-5p was highly expressed in colitis model and miRNA-182-5p inhibitor exerted protective effects on colitis induced by DSS in mice. The protective effects includded improvement of pathological changes, increases in anti-inflammation and anti-oxidative genes, and up-regulation of TGF-β1. Claudin-2 mRNA was predicted as the target of miRNA-182-5p, which was validated via luciferase reporter assay and RNA pull-down assay. Claudin-2 overexpression was found in miRNA-182-5p inhibitor group. Consistent with the role of miRNA-182-5p, claudin-2 overexpression also exerted protective effects on DSS-induced colitis in mice. Inhibition of miRNA-182-5p exerted protective effects on colitis via targeting and upregulating claudin-2. The findings in study provide a new therapeutic strategy for colitis treatment and lay the foundation for future study.

MicroRNA-182 improves spinal cord injury in mice by modulating apoptosis and the inflammatory response via IKKβ/NF-κB

Spinal cord injury (SCI) is one common neurological condition which involves primary injury and secondary injury. Neuron inflammation and apoptosis after SCI is the most important pathological process of this disease. Here, we tried to explore the influence and mechanism of miRNAs on the neuron inflammatory response and apoptosis after SCI. First, by re-analysis of Gene Expression Omnibus dataset (accession GSE19890), miR-182 was selected for further study because of its suppressive effects on the inflammatory response in the various types of injuries. Functional experiments demonstrated that miR-182 overexpression promoted functional recovery, reduced histopathological changes, and alleviated spinal cord edema in mice. It was also observed that miR-182 overexpression reduced apoptosis and attenuated the inflammatory response in spinal cord tissue, as evidenced by the reduction of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β, and the induction of IL-10. Using a lipopolysaccharide (LPS)-induced SCI model in BV-2 cells, we found that miR-182 was downregulated in the BV-2 cells following LPS stimulation, and upregulation of miR-182 improved LPS-induced cell damage, as reflected by the inhibition of apoptosis and the inflammatory response. IκB kinase β (IKKβ), an upstream target of the NF-κB pathway, was directly targeted by miR-182 and miR-182 suppressed its translation. Further experiments revealed that overexpression of IKKβ reversed the anti-apoptosis and anti-inflammatory effects of miR-182 in LPS stimulated BV-2 cells. Finally, we found that miR-182 overexpression blocked the activation of the NF-κB signaling pathway in vitro and in vivo, as demonstrated by the downregulation of phosphorylated (p‑) IκB-α and nuclear p-p65. Taken together, these data indicate that miR-182 improved SCI-induced secondary injury through inhibiting apoptosis and the inflammatory response by blocking the IKKβ/NF-κB pathway. Our findings suggest that upregulation of miR-182 may be a novel therapeutic target for SCI.

Targeting Inflammation after Myocardial Infarction: A Therapeutic Opportunity for Extracellular Vesicles?

After myocardial infarction (MI), a strong inflammatory response takes place in the heart to remove the dead tissue resulting from ischemic injury. A growing body of evidence suggests that timely resolution of this inflammatory process may aid in the prevention of adverse cardiac remodeling and heart failure post-MI. The present challenge is to find a way to stimulate this process without interfering with the reparative role of the immune system. Extracellular vesicles (EVs) are natural membrane particles that are released by cells and carry different macromolecules, including proteins and non-coding RNAs. In recent years, EVs derived from various stem and progenitor cells have been demonstrated to possess regenerative properties. They can provide cardioprotection via several mechanisms of action, including immunomodulation. In this review, we summarize the role of the innate immune system in post-MI healing. We then discuss the mechanisms by which EVs modulate cardiac inflammation in preclinical models of myocardial injury through regulation of monocyte influx and macrophage function. Finally, we provide suggestions for further optimization of EV-based therapy to improve its potential for the treatment of MI.

EGR3-HDAC6-IL-27 Axis Mediates Allergic Inflammation and Is Necessary for Tumorigenic Potential of Cancer Cells Enhanced by Allergic Inflammation-Promoted Cellular Interactions

The objective of this study was to investigate mechanisms of allergic inflammation both in vitro and in vivo in details. For this, RNA sequencing was performed. Early growth response 3 gene (Egr3) was one of the most highly upregulated genes in rat basophilic leukemia (RBL2H3) cells stimulated by antigen. The role of Egr3 in allergic inflammation has not been studied extensively. Egr3 was necessary for passive cutaneous anaphylaxis (PCA) and passive systemic anaphylaxis (PSA). Egr3 promoter sequences contained potential binding site for NF-κB p65. NF-κB p65 directly regulated Egr3 expression and mediated allergic inflammation in vitro. Histone deacetylases (HDACs) is known to be involved in allergic airway inflammation. HDAC6 promoter sequences contained potential binding site for EGR3. EGR3 showed binding to promoter sequences of HDAC6. EGR3 was necessary for increased expression of histone deacetylase 6 (HDAC6) in antigen-stimulated RBL2H3 cells. HDAC6 mediated allergic inflammation in vitro and PSA. TargetScan analysis predicted that miR-182-5p was a negative regulator of EGR3. Luciferase activity assay confirmed that miR-182-5p was a direct regulator of EGR3. MiR-182-5p mimic inhibited allergic inflammation both in vitro and in vivo. Cytokine array showed that HDAC6 was necessary for increased interleukin-27 (IL-27) expression in BALB/C mouse model of PSA. Antigen stimulation did not affect expression of EBI3, another subunit of IL-27 in RBL2H3 cells or BALB/C mouse model of PCA or PSA. IL-27 receptor alpha was shown to be able to bind to HDAC6. IL-27 p28 mediated allergic inflammation in vitro, PCA, and PSA. Mouse recombinant IL-27 protein promoted features of allergic inflammation in an antigen-independent manner. HDAC6 was necessary for tumorigenic and metastatic potential enhanced by PSA. PSA enhanced the metastatic potential of mouse melanoma B16F1 cells in an IL-27-dependent manner. Experiments employing culture medium and mouse recombinant IL-27 protein showed that IL-27 mediated and promoted cellular interactions involving B16F1 cells, lung macrophages, and mast cells during allergic inflammation. IL-27 was present in exosomes of antigen-stimulated RBL2H3 cells. Exosomes from antigen-stimulated RBL2H3 cells enhanced invasion of B16F1 melanoma cells in an IL-27-dependemt manner. These results present evidence that EGR3-HDAC6-IL-27 axis can regulate allergic inflammation by mediating cellular interactions.

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.

Hsa_circ_0004831 downregulation is partially responsible for atorvastatinalleviated human umbilical vein endothelial cell injuries induced by ox-LDL through targeting the miR-182-5p/CXCL12 axis

BACKGROUND

The dysfunction and injury of human umbilical vein endothelial cells (HUVECs) are key events of atherosclerosis (AS). Atorvastatin (ATV) has been shown to play a protective role on endothelial cells. However, the associated molecular mechanisms remain not fully illustrated.

METHODS

HUVECs were treated with oxidized low-density lipoprotein (ox-LDL) to mimic the pathological conditions of endothelial cell injury in AS. Cell injuries were assessed according to cell viability, cell apoptosis, cycle progression, oxidative stress and inflammatory responses using CCK-8 assay, flow cytometry assay or commercial kits. The expression of hsa_circ_0004831, miR-182-5p, and C-X-C motif chemokine 12 (CXCL12) mRNA was examined using quantitative real-time PCR (qPCR). The expression of CXCL12 protein was quantitated by western blot. The predicted target relationship between miR-182-5p and hsa_circ_0004831 or CXCL12 was verified by pull-down assay, dual-luciferase reporter assay or RIP assay.

RESULTS

The expression of hsa_circ_0004831 was upregulated by ox-LDL but downregulated by ATV in HUVECs. ATV promoted cell viability and cell cycle progression but inhibited apoptosis, oxidative stress and inflammation in ox-LDL-treated HUVECs, while the role of ATV was partially reversed by hsa_circ_0004831 overexpression. MiR-182-5p was targeted by hsa_circ_0004831, and hsa_circ_0004831 overexpression-restored apoptosis, oxidative stress and inflammation were blocked by miR-182-5p restoration. Further, CXCL12 was targeted by miR-182-5p, and miR-182-5p inhibition-stimulated apoptosis, oxidative stress and inflammation were lessened by CXCL12 knockdown.

CONCLUSION

Hsa_circ_0004831-targeted miR-182-5p/CXCL12 regulatory network is one of the pathways by which ATV protects against ox-LDL-induced endothelial injuries.

Crosstalk between MicroRNA and Oxidative Stress in Primary Open-Angle Glaucoma

Reactive oxygen species (ROS) plays a key role in the pathogenesis of primary open-angle glaucoma (POAG), a chronic neurodegenerative disease that damages the trabecular meshwork (TM) cells, inducing apoptosis of the retinal ganglion cells (RGC), deteriorating the optic nerve head, and leading to blindness. Aqueous humor (AH) outflow resistance and intraocular pressure (IOP) elevation contribute to disease progression. Nevertheless, despite the existence of pharmacological and surgical treatments, there is room for the development of additional treatment approaches. The following review is aimed at investigating the role of different microRNAs (miRNAs) in the expression of genes and proteins involved in the regulation of inflammatory and degenerative processes, focusing on the delicate balance of synthesis and deposition of extracellular matrix (ECM) regulated by chronic oxidative stress in POAG related tissues. The neutralizing activity of a couple of miRNAs was described, suggesting effective downregulation of pro-inflammatory and pro-fibrotic signaling pathways, including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB), transforming growth factor-beta 2 (TGF-β2), Wnt/β-Catenin, and PI3K/AKT. In addition, with regards to the elevated IOP in many POAG patients due to increased outflow resistance, Collagen type I degradation was stimulated by some miRNAs and prevented ECM deposition in TM cells. Mitochondrial dysfunction as a consequence of oxidative stress was suppressed following exposure to different miRNAs. In contrast, increased oxidative damage by inhibiting the mTOR signaling pathway was described as part of the action of selected miRNAs. Summarizing, specific miRNAs may be promising therapeutic targets for lowering or preventing oxidative stress injury in POAG patients.

MicroRNA-182-5p relieves murine allergic rhinitis via TLR4/NF-κB pathway

Allergic rhinitis (AR) is one of the most common chronic diseases. This study examined whether microRNA (miR)-182-5p plays a role in AR by regulating toll-like receptor 4 (TLR4). First, data demonstrated that TLR4 was a target of miR-182-5p. Subsequently, AR mouse model was established to explore the role of miR-182-5p and TLR4 in AR in vivo. Initially, quantitative reverse transcription-PCR (qRT-PCR) analysis indicated that miR-182-5p was downregulated, while TLR4 expression was upregulated in AR mice. Then we found that miR-182-5p mimic reduced the frequency of sneezing and nose rubbing of the AR mice. In addition, miR-182-5p mimic significantly increased ovalbumin (OVA)-specific IgE and leukotriene C4 expression levels in nasal lavage fluid (NLF) and serum of AR mice. miR-182-5p mimic decreased the number of inflammatory cells in NLF of AR mice. It also reduced the levels of inflammatory factors in the serum of AR mice, such as interleukin (IL)-4, IL-5, IL-13, IL-17 and tumor necrosis factor (TNF)-α, while increasing the release of IFN-γ and IL-2. Finally, miR-182-5p mimic inhibited NF-κB signaling pathway activation in AR mice. However, all effects of miR-182-5p mimic on AR mice were reversed by TLR4-plasmid. In conclusion, miR-182-5p/TLR4 axis may represent a novel therapeutic target for AR.

A Pilot Longitudinal Evaluation of MicroRNAs for Monitoring the Cognitive Impairment in Pediatric Multiple Sclerosis

MicroRNAs (miRNAs), a class of non-coding RNAs, seem to play a key role in complex diseases like multiple sclerosis (MS), as well as in many cognitive functions associated with the disease. In a previous cross-sectional evaluation on pediatric MS (PedMS) patients, the expression of some miRNAs and their target genes were found to be associated with the scores of some neuropsychiatric tests, thus suggesting that they may be involved in early processes of cognitive impairment. To verify these data, we asked the same patients to be re-evaluated after a 1-year interval; unfortunately, only nine of them agreed to this further clinical and molecular analysis. The main results showed that 13 differentially expressed miRNAs discriminated the two time-points. Among them, the expression of miR-182-5p, miR-320a-3p, miR-744-5p and miR-192-5p significantly correlated with the attention and information processing speed performances, whereas the expression of miR-182-5p, miR-451a, miR-4742-3p and miR-320a-3p correlated with the expressive language performances. The analysis of mRNA expression uncovered 58 predicted and/or validated miRNA-target pairs, including 23 target genes, some of them already associated with cognitive impairment, such as the transducing beta like 1 X-linked receptor-1 gene (TBL1XR1), correlated to disorders of neurodevelopment; the Snf2 related CREBBP activator protein gene (SRCAP) that was found implicated in a rare form of dementia; and the glia maturation factor beta gene (GMFB), which has been reported to be implicated in neurodegeneration and neuroinflammation. No molecular pathways involving the most targeted genes survived the adjustment for multiple data. Although preliminary, these findings showed the feasibility of the methods also applied to longitudinal investigations, as well as the reliability of the obtained results. These findings should be confirmed in larger PedMS cohorts in order to identify early markers of cognitive impairment, towards which more efficient therapeutic efforts can be addressed.

HDAC1 promotes artery injury through activation of VAV3 by binding to miR-182-5p in atherosclerotic mice model

Atherosclerosis (AS) is one of the significant chronic inflammatory pathology considering public health impact. Up-regulation of HDAC1 has been proved to be related with endothelial dysfunction which is correlated intimately with AS. Our research aims to investigate how histone deacetylase 1 (HDAC1)/miR-182-5p/vav guanine nucleotide exchange factor 3 (VAV3)/AKT axis participates in AS in terms of molecular mechanism. We detected miR-181-5p in human umbilical vein endothelial cells after treatment with aorta and ox-LDL in AS model mice. Dual luciferase reporter assay was employed to verify interaction of miR-182-5p and VAV3. ChIP was performed to determine the relationship between HDAC1 and promoter of miR-182-5p. Protein levels of HADC1, VAV3, AKT, p-AKT, vascular cell adhesion molecule-1 (VCAM-1), intercellular cell adhesion molecule-1 (ICAM-1), and monocyte chemotactic protein 1 (MCP-1) were detected by western blot analysis. CCK8 and flow cytometry were used to detect cell viability and apoptosis, respectively. After different treatments, the ability of cells to form monoclonal cells was detected, and AS was evaluated by detecting arterial injury and inflammation-related factors. Overexpression of HDAC1 could inhibit HUVECs proliferation and promote AS in mouse model. It was verified by dual luciferase assay that miR-182-5p could bind to VAV3 3'UTR mRNA. Meanwhile, HDAC1 repressed miR-182-5p expression through binding to miR-182-5p promoter and then inhibit VAV3 expression further. In summary, HDAC1 promoted AS through AKT pathway, which was improved by VAV3 activation mediated by miR-182-5p. Our results demonstrated that HDAC1 repressed miR-182-5p and activating AKT pathway via improving VAV3 to promote AS progression.

An update: mechanisms of microRNA in primary open-angle glaucoma

Glaucoma is a disease with characteristic optic neuropathy and loss of vision, leading to blindness, and primary open-angle glaucoma (POAG) is the most common glaucoma type throughout the world. Genetic susceptibility is the main factor in POAG, and most susceptibility genes cause changes in microRNA expression and function, thereby leading to POAG occurrence and development. Increasing evidence indicates that many microRNAs are involved in the regulation of intraocular pressure (IOP) and play an important role in the increase in IOP in POAG. Additionally, microRNA is closely related to optic nerve damage factors (mechanical stress, hypoxia and inflammation). This review discusses the effect of single-nucleotide polymorphisms in POAG-related genes on microRNA and the value of microRNA in the diagnosis and treatment of POAG.

Knockdown of long non-coding RNA TUG1 depresses apoptosis of hippocampal neurons in Alzheimer's disease by elevating microRNA-15a and repressing ROCK1 expression

OBJECTIVE

Many studies have already suggested the role of long non-coding RNAs (lncRNAs) in Alzheimer's disease (AD), but the functions of lncRNA Taurine Upregulated Gene 1 (TUG1) in AD have been scarcely discussed. This study aims to verify how TUG1 affects hippocampal neurons in AD through modulation of microRNA-15a (miR-15a)/Rho-associated protein kinase 1 (ROCK1).

METHOD

AD mice was modeled through injection of β-amyloid 25-35 (Aβ25-35) into the lateral ventricle. After modeling, the mice were injected with altered TUG1 and/or miR-15a agomir lentiviruses. The spatial learning ability and memory ability of mice were detected through Morris water maze test. Hippocampal neuronal apoptosis and oxidative stress indicators in AD mice were then detected. The hippocampal neuron AD model was induced by Aβ25-35. Next, the neurons were, respectively, transfected with altered TUG1 vector and/or miR-15a mimics to determine the proliferation inhibition and apoptosis of hippocampal neurons. The interactions between TUG1 and miR-15a, and between miR-15a and ROCK1 were assessed using bioinformatic prediction, dual luciferase reporter gene assay and RNA-pull-down assay.

RESULTS

In the animal models, Aβ25-35-induced mice exhibited decreased spatial learning and memory ability, obvious pathological injury, promoted hippocampal neuronal apoptosis and decreased antioxidant ability. TUG1 silencing and miR-15a elevation improved spatial learning ability and memory ability, ameliorated pathological injury, depressed neuronal apoptosis, and strengthened antioxidant ability of hippocampal neurons in AD mice. In cellular models, Aβ25-35-treated hippocampal neurons presented inhibited neuronal viability and promoted neuronal apoptosis. TUG1 silencing and miR-15a elevation increased viability and limited apoptosis of Aβ25-35-treated hippocampal neurons. TUG1 specifically bound to miR-15a, and miR-15a targeted ROCK1.

CONCLUSION

Collectively, this study reveals that TUG1 knockdown restricts apoptosis of hippocampal neurons in AD by elevating miR-15a and suppressing ROCK1 expression, and provides a new therapeutic target for AD treatment.

MicroRNA-182-5p protects human lens epithelial cells against oxidative stress-induced apoptosis by inhibiting NOX4 and p38 MAPK signalling

Background

MicroRNAs (miRNAs) are abnormally expressed in various ocular diseases, including age-related cataract. However, the role of miR-182-5p in the progression of age-related cataract remains unclear.

Methods

The expression of miR-182-5p in HLE-B3 cells was detected by qRT-PCR. HLE-B3 cells were transfected with miR-182-5p mimics. CCK-8, EdU, flow cytometry, 2′,7′-dichlorodihydrofluorescein diacetate, JC-1 kit, and western blot were used to assess the cell viability, proliferation, apoptosis, reactive oxygen species (ROS) level, mitochondrial membrane potential (MMP), and protein expression, respectively, in vitro. The relationship between miR-182-5p and NOX4 was confirmed using the dual-luciferase reporter gene analysis.

Results

We found that miR-182-5p expression was significantly decreased by the H₂O₂ exposure. Overexpression of miR-182-5p promoted cell proliferation and inhibited ROS production and apoptosis in H₂O₂-induced HLE-B3 cells. Moreover, p-p-38, p-ERK, and p-JNK were up-regulated in H₂O₂-treated HLE-B3 cells, and overexpression of miR-182-5p reversed the effects of H₂O₂ on HLE-B3 cells. In addition, dual-luciferase reporter assay substantiated that NOX4 was a direct target and downregulated by miR-182-5p.

Conclusions

We concluded that miR-182-5p inhibited lens epithelial cells apoptosis through regulating NOX4 and p38 MAPK signaling, providing a novel biomarker for treatment of age-related cataract.

Mesenchymal stromal cell-derived exosomes attenuate myocardial ischaemia-reperfusion injury through miR-182-regulated macrophage polarization

AIMS

Mesenchymal stromal cells (MSCs) gradually become attractive candidates for cardiac inflammation modulation, yet understanding of the mechanism remains elusive. Strikingly, recent studies indicated that exosomes secreted by MSCs might be a novel mechanism for the beneficial effect of MSCs transplantation after myocardial infarction. We therefore explored the role of MSC-derived exosomes (MSC-Exo) in the immunomodulation of macrophages after myocardial ischaemia/reperfusion (I/R) and its implications in cardiac injury repair.

METHODS AND RESULTS

Exosomes were isolated from the supernatant of MSCs using gradient centrifugation method. Administration of MSC-Exo to mice through intramyocardial injection after myocardial I/R reduced infarct size and alleviated inflammation level in heart and serum. Systemic depletion of macrophages with clodronate liposomes abolished the curative effects of MSC-Exo. MSC-Exo modified the polarization of M1 macrophages to M2 macrophages both in vivo and in vitro. miRNA sequencing of MSC-Exo and bioinformatics analysis implicated miR-182 as a potent candidate mediator of macrophage polarization and toll-like receptor 4 (TLR4) as a downstream target. Diminishing miR-182 in MSC-Exo partially attenuated its modulation of macrophage polarization. Likewise, knock down of TLR4 also conferred cardioprotective efficacy and reduced inflammation level in a mouse model of myocardial I/R.

CONCLUSION

Our data indicate that MSC-Exo attenuates myocardial I/R injury in mice via shuttling miR-182 that modifies the polarization status of macrophages. This study sheds new light on the application of MSC-Exo as a potential therapeutic tool for myocardial I/R injury.

The novel fish miRNA pol-miR-novel_171 and its target gene FAM49B play a critical role in apoptosis and bacterial infection

MicroRNAs (miRNAs) are a type of small, non-coding RNAs that participate in many cellular and biological processes by regulating mRNA stability. In a previous study, we identified 96 Japanese flounder (Paralichthys olivaceus) miRNAs responsive to the infection of Edwardsiella tarda, a bacterial pathogen to fish as well as humans. In the current study, we examined the regulation and function of one novel miRNA, i.e., pol-miR-novel_171, from the above 96 miRNA pool. We found that pol-miR-novel_171 expression was regulated by E. tarda and megalocytivirus in a pathogen-specific manner, and that pol-miR-novel_171 targeted the gene of FAM49B (family with sequence similarity 49 member B) of flounder (named PoFAM49B) by negative interaction with the 3'-UTR of PoFAM49B. To date, the function fish FAM49B is unknown. We found that PoFAM49B expressed in multiple tissues of flounder, and recombinant PoFAM49B interacted with and inhibited the growth of Gram-negative bacterial pathogens. Interference with PoFAM49B expression in flounder cells promoted E. tarda infection. Similar effects on E. tarda infection were observed with pol-miR-novel_171 overexpression. Consistently, in vivo knockdown of PoFAM49B in flounder enhanced E. tarda dissemination in fish tissues. Furthermore, interference with PoFAM49B expression, or overexpression of pol-miR-novel_171, promoted apoptosis of flounder cells, while in vitro and in vivo knockdown of PoFAM49B augmented the expressions of key apoptosis-associated genes. These results revealed for the first time the immune function of fish FAM49B and the regulatory mechanism of a novel fish miRNA by demonstrating that pol-miR-novel_171, via PoFAM49B, played a critical role in apoptosis and anti-bacterial immunity.

Suppression of TRIM8 by microRNA-182-5p restricts tumor necrosis factor-α-induced proliferation and migration of airway smooth muscle cells through inactivation of NF-Κb

MicroRNAs (miRNAs) have emerged as critical modulators involved in the regulation of airway remodeling in asthma. MicroRNA-182-5p (miR-182-5p) has been reported as a key miRNA in regulating the proliferation and migration of various cell types, and its dysfunction contributes is implicated in a wide range of pathological processes. Yet, it remains unknown whether miR-182-5p modulates the proliferation and migration of airway smooth muscle (ASM) cells during asthma. In the present study, we aimed to determine the potential role of miR-182-5p in regulating the proliferation and migration of ASM cells induced by tumor necrosis factor (TNF)-α in vitro. We found that TNF-α stimulation markedly reduced miR-182-5p expression in ASM cells. Gain-of-function experiments showed that miR-182-5p upregulation suppressed the proliferation and migration of ASM cells induced by TNF-α. By contrast, miR-182-5p inhibition had the opposite effect. Notably, tripartite motif 8 (TRIM8) was identified as a target gene of miR-182-5p. TRIM8 expression was induced by TNF-α stimulation, and TRIM8 knockdown markedly impeded TNF-α-induced ASM cell proliferation and migration. Moreover, miR-182-5p overexpression or TRIM8 knockdown significantly downregulated the activation of nuclear factor-κB (NF-κB) induced by TNF-α. However, TRIM8 restoration partially reversed the miR-182-5p-mediated inhibitory effect on TNF-α-induced ASM cell proliferation and migration. In conclusion, our study indicates that miR-182-5p restricts TNF-α-induced ASM cell proliferation and migration through downregulation of NF-κB activation via targeting TRIM8. The results of our study highlight the potential importance of the miR-182-5p/TRIM8/NF-κB axis in the airway remodeling of asthma.

MicroRNA-182 supplies negative feedback regulation to ameliorate lipopolysaccharide-induced ALI in mice by targeting TLR4

Acute lung injury (ALI), characterized by increased excessive pulmonary inflammation, is a pervasive inflammatory disease with clinically high incidence. MicroRNA (miRNAs) have been associated with the progression of multiple diseases and are regarded as novel regulators of inflammation. However, it remains largely unknown whether the miRNAs-mediated regulatory mechanism has an effect on lipopolysaccharide (LPS)-induced inflammation in ALI. We discovered that miR-182 distinctly lessened expression in the lung tissue of mice with ALI and macrophages stimulated by LPS. We also found that overexpression of miR-182 significantly cut down the secretion of inflammatory cytokines, while this change was reversed by inhibition of miR-182. In addition, miR-182 suppressed the activation of NF-κB by targeting TLR4 expression. And it was confirmed that miR-182 directly regulated TLR4 expression at the posttranscriptional level by binding to the 3'-UTR of TLR4. Together, these data suggested that inhibition of TLR4 expression assuaged LPS-stimulated inflammation through negative feedback regulation of miR-182.

Long non-coding RNA UCA1 promotes malignant phenotypes of renal cancer cells by modulating the miR-182-5p/DLL4 axis as a ceRNA

Background

Accumulating literatures have indicated that long non-coding RNAs (lncRNAs) are potential biomarkers that play key roles in tumor development and progression. Urothelial cancer associated 1 (UCA1) is a novel lncRNA that acts as a potential biomarker and is involved in the development of cancers. However, the molecular mechanism of UCA1 in renal cancer is still needed to further explore.

Methods

The relative expression level of UCA1 was determined by Real-Time qPCR in a total of 88 patients with urothelial renal cancer and in different renal cancer cell lines. Loss-of-function experiments were performed to investigate the biological roles of UCA1 and miR-182-5p on renal cancer cell proliferation, migration, apoptosis and tumorigenicity. Comprehensive transcriptional analysis, dual-luciferase reporter assay and western blot etc. were performed to explore the molecular mechanisms underlying the functions of UCA1.

Results

In this study, we found that UCA1 was significantly up-regulated in renal cancer. Moreover, increased UCA1 expression was positively correlated with differentiation and advanced TNM stage. Further experiments demonstrated that knockdown of UCA1 inhibited malignant phenotypes and Notch signal path of renal cancer cells, and miR-182-5p was reverse function as UCA1. UCA1 functioned as a miRNA sponge to positively regulate the expression of Delta-like ligand 4(DLL4) through sponging miR-182-5p and subsequently promoted malignant phenotypes of renal cancer cells, thus UCA1 playing an oncogenic role and miR-182-5p as an antioncogenic one in renal cancer pathogenesis.

Conclusion

UCA1-miR-182-5p-DLL4 axis is involved in proliferation and progression of renal cancer. Thus, this study demonstrated that UCA1 plays a critical regulatory role in renal cancer cell and UCA1 may serve as a potential diagnostic biomarker and therapeutic target of renal cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12943-020-1132-x.

Cadmium-Induced Renal Cell Toxicity Is Associated With MicroRNA Deregulation

Cadmium is an environmental pollutant well known for its nephrotoxic effects. Nevertheless, mechanisms underlying nephrotoxicity continue to be elucidated. MicroRNAs (miRNAs) have emerged in recent years as modulators of xenobiotic-induced toxicity. In this context, our study aimed at elucidating whether miRNAs are involved in renal proximal tubular toxicity induced by cadmium exposure. We showed that cadmium exposure, in 2 distinct renal proximal tubular cell models (renal proximal tubular epithelial cell [RPTEC]/human telomerase reverse transcriptase [hTERT] and human kidney-2), resulted in cytotoxicity associated with morphological changes, overexpression of renal injury markers, and induction of apoptosis and inflammation processes. Cadmium exposure also resulted in miRNA modulation, including the significant upregulation of 38 miRNAs in RPTEC/hTERT cells. Most of these miRNAs are known to target genes whose coding proteins are involved in oxidative stress, inflammation, and apoptosis, leading to tissue remodeling. In conclusion, this study provides a list of dysregulated miRNAs which may play a role in the pathophysiology of cadmium-induced kidney damages and highlights promising cadmium molecular biomarkers that warrants to be further evaluated.

LINC01018 and SMIM25 sponged miR-182-5p in endometriosis revealed by the ceRNA network construction

The current study intended to explore the interaction of the long non-coding RNA (lncRNA), microRNA (miRNA), and messenger RNA (mRNA) under the background of competitive endogenous RNA (ceRNA) network in endometriosis (EMs). The differentially expressed miRNAs (DEmiRs), differentially expressed lncRNA (DELs), and differentially expressed genes (DEGs) between EMs ectopic (EC) and eutopic (EU) endometrium based on three RNA-sequencing datasets (GSE105765, GSE121406, and GSE105764) were identified, which were used for the construction of ceRNA network. Then, DEGs in the ceRNA network were performed with Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and protein-protein interaction (PPI) analysis. Besides, the DEmiRs in the ceRNA network were validated in GSE124010. And the target DELs and DEGs of verified DEmiRs were validated in GSE86534. The correlation of verified DEmiRs, DEGs, and DELs was explored. Moreover, gene set enrichment analysis (GSEA) was applied to investigate the function of verified DEmiRs, DEGs, and DELs. Overall, 1352 DEGs and 595 DELs from GSE105764, along with 27 overlapped DEmiRs between GSE105765 and GSE121406, were obtained. Subsequently, a ceRNA network, including 11 upregulated and 16 downregulated DEmiRs, 7 upregulated and 13 downregulated DELs, 48 upregulated and 46 downregulated DEGs, was constructed. The GO and KEGG pathway analysis showed that this ceRNA network probably was associated with inflammation-related pathways. Furthermore, hsa-miR-182-5p and its target DELs (LINC01018 and SMIM25) and DEGs (BNC2, CHL1, HMCN1, PRDM16) were successfully verified in the validation analysis. Besides, hsa-miR-182-5p was significantly negatively correlated with these target DELs and DEGs. The GSEA analysis implied that high expression of LINC01018, SMIM25, and CHL1, and low expression of hsa-miR-182-5p would activate inflammation-related pathways in endometriosis EU samples.LINC01018 and SMIM25 might sponge hsa-miR-182-5p to upregulate downstream genes such as CHL1 to promote the development of endometriosis.

Diagnostic and theranostic microRNAs in the pathogenesis of atherosclerosis

MicroRNAs (miRNAs) are a group of small single strand and noncoding RNAs that regulate several physiological and molecular signalling pathways. Alterations of miRNA expression profiles may be involved with pathophysiological processes underlying the development of atherosclerosis and cardiovascular diseases, including changes in the functions of the endothelial cells and vascular smooth muscle cells, such as cell proliferation, migration and inflammation, which are involved in angiogenesis, macrophage function and foam cell formation. Thus, miRNAs can be considered to have a crucial role in the progression, modulation and regulation of every stage of atherosclerosis. Such potential biomarkers will enable us to predict therapeutic response and prognosis of cardiovascular diseases and adopt effective preclinical and clinical treatment strategies. In the present review article, the current data regarding the role of miRNAs in atherosclerosis were summarized and the potential miRNAs as prognostic, diagnostic and theranostic biomarkers in preclinical and clinical studies were further discussed. The highlights of this review are expected to present opportunities for future research of clinical therapeutic approaches in vascular diseases resulting from atherosclerosis with an emphasis on miRNAs.

Targeting the Immune System With Mesenchymal Stromal Cell-Derived Extracellular Vesicles: What Is the Cargo's Mechanism of Action?

The potent immunomodulatory activities displayed by mesenchymal stromal cells (MSCs) have motivated their application in hundreds of clinical trials to date. In some countries, they have subsequently been approved for the treatment of immune disorders such as Crohn's disease and graft-versus-host disease. Increasing evidence suggests that their main mechanism of action in vivo relies on paracrine signaling and extracellular vesicles. Mesenchymal stromal cell-derived extracellular vesicles (MSC-EVs) play a prominent role in intercellular communication by allowing the horizontal transfer of microRNAs, mRNAs, proteins, lipids and other bioactive molecules between MSCs and their targets. However, despite the considerable momentum gained by MSC-EV research, the precise mechanism by which MSC-EVs interact with the immune system is still debated. Available evidence is highly context-dependent and fragmentary, with a limited number of reports trying to link their efficacy to specific active components shuttled within them. In this concise review, currently available evidence on the molecular mechanisms underlying the effects of MSC-EV cargo on the immune system is analyzed. Studies that pinpoint specific MSC-EV-borne mediators of immunomodulation are highlighted, with a focus on the signaling events triggered by MSC-EVs in target immune cells. Reports that study the effects of preconditioning or “licensing” in MSC-EV-mediated immunomodulation are also presented. The need for further studies that dissect the mechanisms of MSC-EV cargo in the adaptive immune system is emphasized. Finally, the major challenges that need to be addressed to harness the full potential of these signaling vehicles are discussed, with the ultimate goal of effectively translating MSC-EV treatments into the clinic.

miR‑455 targets FABP4 to protect human endometrial stromal cells from cytotoxicity induced by hydrogen peroxide

Oxidative stress and dysregulation of antioxidant systems are associated with various complications in pregnancy. Endometriosis is a common gynecologic disease that affects women of reproductive age. Recent studies have indicated that oxidative stress may be involved in the pathophysiology of endometriosis. It has been reported that microRNAs can regulate the cellular response to oxidative stress, and mounting evidence indicates that fatty acid binding protein 4 (FABP4) plays an essential role in the regulation of systemic redox capacity. In the present study, we demonstrated that miR-455 is a putative FABP4-targeting miRNA. A luciferase activity assay revealed that miR-455 can successfully bind to the 3′-UTR of FABP4. Overexpression of miR-455 led to the downregulation of FABP4 at both the mRNA and protein levels in a human endometrial stromal cell line. Then, the roles of miR-455 and FABP4 in oxidative stress induced by hydrogen peroxide (H₂O₂) in human endometrial stromal cells were examined. We found that ectopic expression of miR-455 protected cells from damage caused by H₂O₂. Further investigation found that forced expression of miR-455 reduced the level of reactive oxygen species (ROS) and malondialdehyde (MDA), while the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were promoted. Silencing of FABP4 also generated cytoprotective effects against H₂O₂ in human endometrial stromal cells. Moreover, overexpression FABP4 abrogated the miR-455-mediated antioxidative stress effects in cells. Taken together, we propose that miR-455 protects human endometrial stromal cells from oxidative stress at least partly via regulation of FABP4.

CD 36: Focus on Epigenetic and Post-Transcriptional Regulation

CD36 is a transmembrane protein involved in fatty acid translocation, scavenging for oxidized fatty acids acting as a receptor for adhesion molecules. It is expressed on macrophages, as well as other types of cells, such as endothelial and adipose cells. CD36 participates in muscle lipid uptake, adipose energy storage, and gut fat absorption. Recently, several preclinical and clinical studies demonstrated that upregulation of CD36 is a prerequisite for tumor metastasis. Cancer metastasis-related research emerged much later and has been less investigated, though it is equally or even more important. CD36 protein expression can be modified by epigenetic changes and post-transcriptional interference from non-coding RNAs. Some data indicate modulation of CD36 expression in specific cell types by epigenetic changes via DNA methylation patterns or histone tails, or through miRNA interference, but this is largely unexplored. The few papers addressing this topic refer mostly to lipid metabolism-related pathologies, whereas in cancer research, data are even more scarce. The aim of this review was to summarize major epigenetic and post-transcriptional mechanisms that impact CD36 expression in relation to various pathologies while highlighting the areas in need of further exploration.