miR-21 Mimic Research Articles

MiR-210 promotes immune- and suppresses oocyte meiosis-related genes in the zebrafish ovarian cells

microRNA-210 (miRNA), a well-documented miRNA, has been implicated in a myriad of biological processes, including responses to hypoxia, angiogenesis, cell proliferation, and male infertility in humans. However, a comprehensive understanding of its functions in fish requires further investigation. This study pursued to elucidate the downstream effect of dre-miR-210-5p on primary ovarian cell culture in zebrafish (Danio rerio), an animal model. A protocol was settled down by incubations with either an miR-210 mimic or a scrambled miRNA in the isolated ovaries. RNA-sequencing analysis identified ∼6000 differentially expressed target genes revealing that downregulated genes were associated with reproduction-related pathways while immune-related pathways displayed an upregulated pattern. To identify molecular markers, predicted target genes were classified into reproduction and immune cell types. These findings underscore the existence of a profound interplay between the reproductive and immune systems, with miR-210 emerging as a pivotal player in orchestrating transcriptomic alterations within fish ovaries.

Targeted delivery of miR-1 to the heart using clinical contrast ultrasound

Pathological left-ventricle hypertrophy is a cardiovascular disorder resulting in the thickening of the ventricle wall due to abnormal cardiomyocyte growth. The downregulation of miR-1 in hypertrophic cardiomyocytes has been identified as an early disease marker, with the delivery of miR-1 as a promising treatment strategy. Ultrasound and microbubbles offer an exciting approach to image-guided and site-specific cardiac gene delivery. The objective of this study is to show the feasibility of viable ultrasound and microbubble-mediated delivery of miR-1 in vivo. Sprague–Dawley rats were injected via tail vein with a suspension of miR-1 mimic (0.6 mg/kg) and Definity. The rats were then treated with a high MI (1.34) flash sequence for 20 min using a C5-2 probe with a Phillips iU22. Delivery was confirmed on isolated heart tissue with RT-qPCR and Western blots for miR-1 and protein expression, respectively. miR-1 delivery in healthy male rats resulted in a 1.33-fold (p = 0.05) increase in miR-1 as compared to sham controls. This resulted in a decrease in hypertrophic protein expression (1.18-fold in TWF1, p = 0.17; 1.23-fold in MEF2A, p = 0.07; 1.25-fold in CX43, p = 0.03). Our data demonstrate the feasibility of using ultrasound and microbubbles as an image-guided delivery method for molecular therapeutics in cardiovascular disorders.

MiR-155 promotes compensatory lung growth by inhibiting JARID2 activation of CD34+ endothelial progenitor cells.

Bone marrow-derived CD34-positive (CD34+) endothelial progenitor cells (EPCs) has unique functions in the mechanism of compensatory lung growth (CLG). The content of this study is mainly to describe the effect of microRNA (miR)-155 in the mechanisms of EPCs and CLG. Our study found that transfection of miR-155 mimic could promote EPC proliferation, migration and tube formation, while transfection of miR-155 inhibitor had the opposite effect. It was also found that transfection of pc-JARID2 inhibited EPC proliferation, migration and tube formation, while transfection of si-JARID2 had the opposite effect. miR-155 can target and negatively regulate JARID2 expression. Overexpression of JARID2 weakened the promoting effects of miR-155 mimic on EPC proliferation, migration, and tubular formation, while silencing JARID2 weakened the inhibitory effects of miR-155 inhibitors on EPC proliferation, migration, and tubular formation. Transplantation of EPCs transfected with miR-155 mimic into the left lung model effectively increased lung volume, total alveolar number, diaphragm surface area, and lung endothelial cell number, while transplantation of EPCs co-transfected with miR-155 mimic and pc-JARID2 reversed this phenomenon. Overall, we found that miR-155 activates CD34+ EPC by targeting negative regulation of JARID2 and promotes CLG.

Au@16-pH-16/miR-21 mimic nanosystem: An efficient treatment for obesity through browning and thermogenesis induction

Despite the abundance of registered clinical trials worldwide, the availability of effective drugs for obesity treatment is limited due to their associated side effects. Thus, there is growing interest in therapies that stimulate energy expenditure in white adipose tissue. Recently, we demonstrated that the delivery of a miR-21 mimic using JetPEI effectively inhibits weight gain in an obese mouse model by promoting metabolism, browning, and thermogenesis, suggesting the potential of miR-21 mimic as a treatment for obesity. Despite these promising results, the implementation of more advanced delivery system techniques for miR-21 mimic would greatly enhance the advancement of safe and efficient treatment approaches for individuals with obesity in the future. Our objective is to explore whether a new delivery system based on gold nanoparticles and Gemini surfactants (Au@16-ph-16) can replicate the favorable effects of the miR-21 mimic on weight gain, browning, and thermogenesis. We found that dosages as low as 0.2 μg miR-21 mimic /animal significantly inhibited weight gain and induced browning and thermogenic parameters. This was evidenced by the upregulation of specific genes and proteins associated with these processes, as well as the biogenesis of beige adipocytes and mitochondria. Significant increases in miR-21 levels were observed in adipose tissue but not in other tissue types. Our data indicates that Au@16-ph-16 could serve as an effective delivery system for miRNA mimics, suggesting its potential suitability for the development of future clinical treatments against obesity.

MiR-378 Inhibits Angiotensin II-Induced Cardiomyocyte Hypertrophy by Targeting AKT2.

Cardiomyocyte hypertrophy plays a crucial role in heart failure development, potentially leading to sudden cardiac arrest and death. Previous studies suggest that micro-ribonucleic acids (miRNAs) show promise for the early diagnosis and treatment of cardiomyocyte hypertrophy.To investigate the miR-378 expression in the cardiomyocyte hypertrophy model, reverse transcription-polymerase chain reaction (RT-qPCR), Western blot, and immunofluorescence tests were conducted in angiotensin II (Ang II)-induced H9c2 cells and Ang II-induced mouse model of cardiomyocyte hypertrophy. The functional interaction between miR-378 and AKT2 was studied by dual-luciferase reporter, RNA pull-down, Western blot, and RT-qPCR assays.The results of RT-qPCR analysis showed the downregulated expression of miR-378 in both the cell and animal models of cardiomyocyte hypertrophy. It was observed that the introduction of the miR-378 mimic inhibited the hypertrophy of cardiomyocytes induced by Ang II. Furthermore, the co-transfection of AKT2 expression vector partially mitigated the negative impact of miR-378 overexpression on Ang II-induced cardiomyocytes. Molecular investigations provided evidence that miR-378 negatively regulated AKT2 expression by interacting with the 3' untranslated region (UTR) of AKT2 mRNA.Decreased miR-378 expression and AKT2 activation are linked to Ang II-induced cardiomyocyte hypertrophy. Targeting miR-378/AKT2 axis offers therapeutic opportunity to alleviate cardiomyocyte hypertrophy.

MicroRNA-122 protects against interferon-α-induced hepatic inflammatory response via the Janus kinase-signal transducer and activator of transcription pathway.

Significant overlap in the epidemiology and coinfection of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) has been identified, which accelerates the development of severe liver cirrhosis and hepatocellular carcinoma worldwide. Interferon-α (IFN-α), a cytokine with antiviral properties, exerts profound physiological effects on innate immunity by regulating interferon-stimulated genes (ISGs) within cells. However, the underlying mechanism of IFN-α in hepatic inflammation remains to be fully elucidated. Here, we utilized LO2 cells treated with the recombinant IFN-α protein and conducted microRNA (miR) sequencing. MiR-122-3p and miR-122-5p_R+1 were the most enriched miRNAs involved in the pathogenesis of IFN-α-induced inflammatory responses and were significantly downregulated by IFN-α treatment. Furthermore, we identified interferon induced protein with tetratricopeptide repeats 1 (IFIT1) as a potential target gene of miR-122. IFN-α markedly increased the expression of proinflammatory cytokines and fibrogenic genes but decreased the mRNA expression of ISGs. Additionally, IFN-α significantly activated the NF-κB p-p65, MAPK p-p38, and Jak/STAT pathways to trigger inflammation. Importantly, supplementation with a miR-122 mimic significantly alleviated IFN-α-induced inflammation and induced IFIT1 expression in LO2 cells. Conversely, the suppression of miR-122 markedly exacerbated the inflammatory response triggered by IFN-α. Furthermore, silencing IFIT1 via an siRNA elicited an inflammatory response, whereas IFIT1 overexpression ameliorated hepatic inflammation and fibrosis in a manner comparable to that induced by IFN-α treatment. Taken together, our findings suggest that miR-122 and its target, IFIT1, reciprocally regulate the inflammatory response associated with IFN through the Jak/STAT pathway.

Therapeutic Potential of Intravenous miR-21 Mimic after Stroke Following STAIR Criteria.

The microRNA-21 (miR-21) levels in the brain are crucial in determining post-stroke brain damage and recovery. The miR-21 exerts neuroprotection by targeting mRNAs that translate proteins that mediate brain damage. We currently determined the efficacy and efficiency of intravenously administered miR-21 mimic after focal cerebral ischemia in mice. Adult male mice were intravenously administered with either control mimic or miR-21 mimic at 5min/2 h after reperfusion following 1h transient middle cerebral artery occlusion to determine the therapeutic window of miR-21 mimic. Adult female, type-2 diabetic male, aged male, and aged female mice were administered with control/miR-21 mimic at 5 min after reperfusion following 35min/1h transient middle cerebral artery occlusion. Early administration of miR-21 mimic significantly reduced brain damage and promoted long-term recovery after stroke. Further, miR-21 mimic is more effective in males than in females subjected to stroke. However, delayed treatment with miR-21 mimic is not efficacious, and type-2 diabetic subjects show no improvement with miR-21 mimic treatment.

Berberine modulates the immunometabolism and differentiation of CD4+ T cells alleviating experimental arthritis by suppression of M1-exo-miR155

BackgroundThe inflammatory cascade mediated by macrophages and T cells is considered to be an important factor in promoting the progression of rheumatoid arthritis (RA). Our previous study found that berberine (BBR) can therapeutically impact adjuvant arthritis (AA) in rats through the regulation of macrophage polarization and the balance of Th17/Treg. However, whether BBR's effects on CD4+T cells response are related to its suppression of M1 macrophage still unclear. PurposeThe study aimed to estimate the mechanism of BBR in regulating the immunometabolism and differentiation of CD4+T cells are related to exosome derived from M1-macrophage (M1-exo). Study-design/methodsMice model of collagen-induced arthritis (CIA) was established to investigate the antiarthritic effect of BBR was related with regulation of M1-exo to balance T cell subsets. Bioinformatics analysis using the GEO database and meta-analysis. In vitro, we established the co-culture system involving M1-exo and CD4+ T cells to examine whether BBR inhibits CD4+T cell activation and differentiation by influencing M1-exo-miR155. Exosome was characterized using transmission electron microscopy and western blot analysis, macrophage and CD4+T cell subpopulation were detected by flow cytometry. Further, the metabolic profiles of CD4+T cells were assessed by ECAR, OCR, and the level of glucose, lactate, intracellular ATP. ResultBBR reinstates CD4+ T cell homeostasis and reduces miR155 levels in both M1-exo and CD4+ T cells obtained from mice with CIA. In vitro, we found exosomes are indispensable for M1-CM on T lymphocyte activation and differentiation. BBR reversed M1-exo facilitating the activation and differentiation of CD4+T cells. Furthermore, BBR reversed glycolysis reprogramming of CD4+T cells induced by M1-exo, while these regulation effects were significantly weakened by miR155 mimic. ConclusionThe delivery of miR-155 by M1-exo contributes to CD4+ T cell immunometabolism dysfunction, a process implicated in the development of RA. The anti-arthritic effect of BBR is associated with the suppression of glycolysis and the disruption of CD4+ T cell subsets balance, achieved by reducing the transfer of M1-exo-miR155 into T cells.

Leonurine alleviates rheumatoid arthritis by regulating the Hippo signaling pathway

BackgroundRheumatoid arthritis (RA) is a chronic autoimmune disease that can cause joint inflammation and damage. Leonurine (LE) is an alkaloid found in Leonurus heterophyllus. It has anti-inflammatory effects. Hypothesis/PurposeThe molecular mechanisms by which LE acts in RA are unclear and further investigation is required. MethodsMice with collagen-induced arthritis (CIA), and RA-fibroblast-like synoviocytes (FLSs) isolated from them were used as in vivo and in vitro models of RA, respectively. The therapeutic effects of LE on CIA-induced joint injury were investigated by micro-computed tomography, and staining with hematoxylin and eosin and Safranin-O/Fast Green. Cell Counting Kit-8, a Transwell® chamber, enzyme-linked immunosorbent assays, RT-qPCR, and western blotting were used to investigate the effects of LE on RA-FLS viability, migratory capacity, inflammation, microRNA-21 (miR-21) levels, the Hippo signaling pathway, and the effects and intrinsic mechanisms of related proteins. Dual luciferase was used to investigate the binding of miR-21 to YOD1 deubiquitinase (YOD1) and yes-associated protein (YAP). Immunofluorescence was used to investigate the localization of YAP within the nucleus and cytoplasm. ResultsTreatment with LE significantly inhibited joint swelling, bone damage, synovial inflammation, and proteoglycan loss in the CIA mice. It also reduced the proliferation, cell colonization, migration/invasion, and inflammation levels of RA-FLSs, and promoted miR-21 expression in vitro. The effects of LE on RA-FLSs were enhanced by an miR-21 mimic and reversed by an miR-21 inhibitor. The dual luciferase investigation confirmed that both YOD1 and YAP are direct targets of miR-21. Treatment with LE activated the Hippo signaling pathway, and promoted the downregulation and dephosphorylation of MST1 and LATS1 in RA, while inhibiting the activation of YOD1 and YAP. Regulation of the therapeutic effects of LE by miR-21 was counteracted by YOD1 overexpression, which caused the phosphorylation of YAP and prevented its nuclear ectopic position, thereby reducing LE effect on pro-proliferation-inhibiting apoptosis target genes. ConclusionLE regulates the Hippo signaling pathway through the miR-21/YOD1/YAP axis to reduce joint inflammation and bone destruction in CIA mice, thereby inhibiting the growth and inflammation of RA-FLSs. LE has potential for the treatment of RA.

MicroRNA-155 targets SOCS1 to inhibit osteoclast differentiation during orthodontic tooth movement

BackgroundMicroRNA-155 (miR-155) is a multifunctional miRNA whose expression is known to be involved in a range of physiological and pathological processes. Its association with several oral diseases has been established. However, the specific role of miR-155 in orthodontic tooth movement remains unclear. In this study, we investigated the impact of miR-155 on osteoclast differentiation and orthodontic tooth movement models, aiming to explore the underlying mechanisms.MethodsIn this experiment, we utilized various agents including miR-155 mimic, miR-155 inhibitor, as well as non-specific sequences (NC mimic & NC inhibitor) to treat murine BMMNCs. Subsequently, osteoclast induction (OC) was carried out to examine the changes in the differentiation ability of monocytes under different conditions. To assess these changes, we employed RT-PCR, Western blotting, and TRAP staining techniques. For the orthodontic tooth movement model in mice, the subjects were divided into two groups: the NaCl group (injected with saline solution) and the miR-155 inhibitor group (injected with AntagomiR-155). We observed the impact of orthodontic tooth movement using stereoscopic microscopy, micro-CT, and HE staining. Furthermore, we performed RT-PCR and Western blotting analyses on the tissues surrounding the moving teeth. Additionally, we employed TargetScan to predict potential target genes of miR-155.ResultsDuring osteoclast induction of BMMNCs, the expression of miR-155 exhibited an inverse correlation with osteoclast-related markers. Overexpression of miR-155 led to a decrease in osteoclast-related indexes, whereas underexpression of miR-155 increased those indexes. In the mouse orthodontic tooth movement model, the rate of tooth movement was enhanced following injection of the miR-155 inhibitor, leading to heightened osteoclast activity. TargetScan analysis identified SOCS1 as a target gene of miR-155.ConclusionsOur results suggest that miR-155 functions as an inhibitor of osteoclast differentiation, and it appears to regulate osteoclasts during orthodontic tooth movement. The regulatory mechanism of miR-155 in this process involves the targeting of SOCS1.

Circular RNA hsa_circ_0051246 acts as a microRNA-375 sponge to promote the progression of gastric cancer stem cells via YAP1.

Gastric cancer (GC) stem cells play an important role in GC progression. Circular RNAs (circRNAs) act as microRNA (miRNA) sponges and inhibit the biological function of miRNAs in GC cytoplasm. MiRNAs also participate in GC progress. circ_0051246 was shown to be associated with miR-375 after analyzing GC microarray data GSE78091 and GSE83521. The oncoprotein Yes-associated protein 1 (YAP1) is targeted by miR-375 and can be inactivated via the Hippo tumor suppressor pathway. Due to insufficient research on circ_0051246, this study aimed to investigate its relationship with miR-375 and YAP1 in cancer stem cells (CSCs). SGC-7901 CSCs were used to establish knockdown/overexpression models of circ_0051246, miR-375, and YAP1. Malignant phenotypes of CSCs were assessed using Cell Counting Kit 8, colony/sphere formation, 5-Ethynyl-2'-deoxyuridine assay, flow cytometry, Transwell, and wound healing assays. To detect the interactions between circ_0051246, miR-375, and YAP1 in CSCs, a dual-luciferase reporter assay and fluorescence in situ hybridization were performed. In addition, 24 BALB/c nude mice were used to establish orthotopic xenograft tumor models. Four groups of mice were injected with CSCs (1 × 106 cells/100 µL) with circ_0051246 knockdown, miR-375 overexpression, or their respective control cells, and tumor progression and gene expression were observed by hematoxylin-eosin staining, immunohistochemistry. Western blot and quantitative real-time PCR were utilized to examine protein and gene expression, respectively. Circ_0051246 silencing reduced viability, promoted apoptosis, and inhibited proliferation, migration and invasion of CSCs. The functional effects of miR-375 mimics were comparable to those of circ_0051246 knockdown; however, the opposite was observed after miR-375 inhibitors treatment of CSCs. Furthermore, circ_0051246-overexpression antagonized the miR-375 mimics' effects on CSCs. Additionally, YAP1 overexpression promoted CSC features, such as self-renewal, migration, and invasion, inhibited apoptosis and E-cadherin levels, and upregulated the expression of N-cadherin, vimentin, YAP1, neurogenic locus notch homolog protein 1, and jagged canonical notch ligand 1. Conversely, YAP1-silenced produced the opposite effect. Moreover, miR-375 treatment antagonized the malignant effects of YAP1 overexpression in CSCs. Importantly, circ_0051246 knockdown and miR-375 activation suppressed CSC tumorigenicity in vivo. This study highlights the promotion of circ_0051246-miR-375-YAP1 axis activation in GC progression and provides a scientific basis for research on the molecular mechanism of CSCs.

A Novel Bioswitchable miRNA Mimic Delivery System: Therapeutic Strategies Upgraded from Tetrahedral Framework Nucleic Acid System for Fibrotic Disease Treatment and Pyroptosis Pathway Inhibition.

There has been considerable interest in gene vectors and their role in regulating cellular activities and treating diseases since the advent of nucleic acid drugs. MicroRNA (miR) therapeutic strategies are research hotspots as they regulate gene expression post-transcriptionally and treat a range of diseases. An original tetrahedral framework nucleic acid (tFNA) analog, a bioswitchable miR inhibitor delivery system (BiRDS) carrying miR inhibitors, is previously established; however, it remains unknown whether BiRDS can be equipped with miR mimics. Taking advantage of the transport capacity of tetrahedral framework nucleic acid (tFNA) and upgrading it further, the treatment outcomes of a traditional tFNA and BiRDS at different concentrations on TGF-β- and bleomycin-induced fibrosis simultaneously in vitro and in vivo are compared. An upgraded traditional tFNA is designed by successfully synthesizing a novel BiRDS, carrying a miR mimic, miR-27a, for treating skin fibrosis and inhibiting the pyroptosis pathway, which exhibits stability and biocompatibility. BiRDS has three times higher efficiency in delivering miRNAs than the conventional tFNA with sticky ends. Moreover, BiRDS is more potent against fibrosis and pyroptosis-related diseases than tFNAs. These findings indicate that the BiRDS can be applied as a drug delivery system for disease treatment.

Abstract 18622: The Role of MicroRNA-98 in the Context of Myocardial Ischemia-Reperfusion Injury During Late Pregnancy

BACKGROUND: We have shown that the late-pregnant (LP) rodent exhibits a higher susceptibility to myocardial ischemia-reperfusion injury (IRI) compared to non-pregnant (NP). The molecular mechanisms remain unclear. The dysregulation of multiple microRNAs (miRs) in IRI suggests their potential as promising targets for therapeutic interventions. Methods: Female Sprague-Dawley rats in both NP and LP states underwent occlusion of the left anterior descending coronary artery (LAD) for a duration of 45 minutes, followed by reperfusion for 3 hours or 24 hours. Expression of miR was assessed via fluorescent in situ hybridization. MicroRNA-microarray profiling was conducted on hearts of NP and LP rats subjected to IRI. Female H9c2 rat cardiomyoblast cells were transfected with miR mimics and inhibitors, and subjected to hypoxia/reoxygenation. Blood samples were obtained from NP, LP, and ischemic heart disease (IHD) patients. MiR98 inhibitor was administered at the initiation of reperfusion. Results: MicroRNA-microarray analysis revealed upregulation of microRNA-98-5p (miR-98) in LV of LP at baseline, and a further upregulation after IRI. The expression of Stat3 and Pgc-1α were decreased in LV of LP rats compared to NP rats upon IRI. Fluorescent in situ hybridization revealed expression of miR-98 in cardiomyocytes in NP rats, which was increased in LP rats. Overexpression of miR-98 in vitro in female H9c2 cells decreased Stat3 and Pgc-1α levels, and promoted apoptosis, oxidative stress, and inflammatory markers. MiR-98 inhibitor in LP rats at the onset of reperfusion reduced infarct size, apoptosis, oxidative stress, and inflammatory markers and was associated with upregulation of Stat3 and Pgc-1α. In humans, plasma miR-98 levels were significantly higher in healthy LP compared to healthy NP individuals and even higher in LP patients with IHD patients. CONCLUSIONS: We show the detrimental effects of miR-98 by promoting cardiomyocyte oxidative stress, inflammation, and apoptosis via its targets Stat3 and Pgc-1α in the context of late pregnancy. MiR-98 could be a novel cardio-protective strategy or biomarker in late pregnancy.

MiR-210 promotes bone formation in ovariectomized rats by regulating osteogenic/adipogenic differentiation of bone marrow mesenchymal stem cells through downregulation of EPHA2

PurposeIn osteoporosis, the balance between osteogenic and adipogenic differentiation of mesenchymal stem cells (MSCs) is disrupted. The osteogenic differentiation of bone marrow MSCs (BMSCs) is important for improving osteoporosis. The aim of this study was to explore the role and molecular mechanism of miR-210 in the balance of osteogenic/adipogenic differentiation of BMSCs in postmenopausal osteoporosis.MethodsPostmenopausal osteoporosis rat models were constructed by ovariectomy (OVX). BMSCs were isolated from the femur in rats of Sham and OVX groups. MiR-210 was overexpressed and suppressed by miR-210 mimics and inhibitor, respectively. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the relative mRNA expression of miR-210, ephrin type-A receptor 2 (EPHA2), alkaline phosphatase (ALP), osterix (OSX), osteocalcin (Bglap), Runt-related transcription factor 2 (Runx2), peroxisome proliferator activated receptor gamma, and fatty acid binding protein 4 (FABP4) in each group of rat femoral tissues or BMSCs. Western blot was applied to detect the protein expression level of EPHA2 in rat femoral tissues and cells. Alizarin red S staining and oil red O staining were performed to assess the osteogenic and adipogenic differentiation of BMSCs, respectively. In addition, the targeting relationship between miR-210 and EPHA2 was verified by a dual luciferase gene reporter assay.ResultsThe expression of miR-210 was significantly reduced in femoral tissues and BMSCs of OVX rats, and its low expression was associated with reduced bone formation. The osteogenic differentiation was enhanced in OVX rats treated with miR-210 mimic. Overexpression of miR-210 in transfected BMSCs was also found to significantly promote osteogenic differentiation and even inhibit adipogenic differentiation in BMSCs, while knockdown of miR-210 did the opposite. Further mechanistic studies showed that miR-210 could target and inhibit the expression of EPHA2 in BMSCs, thus promoting osteogenic differentiation and inhibiting adipogenic differentiation of BMSCs.ConclusionMiR-210 promotes osteogenic differentiation and inhibits adipogenic differentiation of BMSCs by down-regulating EPHA2 expression. As it plays an important role in the osteogenic/adipogenic differentiation of osteoporosis, miR-210 can serve as a potential miRNA biomarker for osteoporosis.

Inhibition of LncRNA SNHG14 protects chondrocyte from injury in osteoarthritis via sponging miR-137

Long-chain noncoding small nucleolar RNA host gene 14 (LncRNA SNHG14) is highly expressed in various diseases and promotes diseases progression, but the role and mechanism of LncRNA SNHG14 on targeting miR-137 in promoting osteoarthritis (OA) chondrocyte injury remains unclear. To measure the expression of the LncRNAs SNHG14 and miR-137, cell survival, inflammatory response, chondrocyte apoptosis, and extracellular matrix (ECM) levels, we subjected human chondrocytes to a variety of lipopolysaccharide (LPS) concentrations. To measure the luciferase activity of SNHG14-WT and SNHG14-MUT transfected with miR-137 mimic or miR-NC mimic, luciferase reporter genes were utilized. The results showed that chondrocyte viability was significantly inhibited with LPS treatment and chondrocyte inflammatory response, apoptosis and extracellular matrix degradation were significantly increased. However, the above results were significantly reversed after LncRNA SNHG14 inhibition. The luciferase activity bound to miR-137 was decreased in SNHG14-WT group, but there was no change in SNHG14-mut group, which indicated that LncRNA SNHG14 inhibited miR-137 expression as a miRNA sponge. In conclusion, inhibition of LncRNA SNHG14 attenuates chondrocyte inflammatory response, apoptosis and extracellular matrix degradation by targeting miR-137 in LPS induced chondrocytes.

Dual scaffold delivery of miR-210 mimic and miR-16 inhibitor enhances angiogenesis and osteogenesis to accelerate bone healing

Angiogenesis is critical for successful bone repair, and interestingly, miR-210 and miR-16 possess counter-active targets involved in both angiogenesis and osteogenesis: miR-210 acts as an activator by silencing EFNA3 & AcvR1b, while miR-16 inhibits both pathways by silencing VEGF & Smad5. It was thus hypothesized that dual delivery of both a miR-210 mimic and a miR-16 inhibitor from a collagen-nanohydroxyapatite scaffold system may hold significant potential for bone repair. Therefore, this systems potential to rapidly accelerate bone repair by directing enhanced angiogenic-osteogenic coupling in host cells in a rat calvarial defect model at a very early 4 week timepoint was assessed. In vitro, the treatment significantly enhanced angiogenic-osteogenic coupling of human mesenchymal stem cells, with enhanced calcium deposition after just 10 days in 2D and 14 days on scaffolds. In vivo, these dual-miRNA loaded scaffolds showed more than double bone volume and vessel recruitment increased 2.3 fold over the miRNA-free scaffolds. Overall, this study demonstrates the successful development of a dual-miRNA mimic/inhibitor scaffold for enhanced in vivo bone repair for the first time, and the possibility of extending this ‘off-the-shelf’ platform system to applications beyond bone offers immense potential to impact a myriad of other tissue engineering areas. Statement of significancemiRNAs have potential as a new class of bone healing therapeutics as they can enhance the regenerative capacity of bone-forming cells. However, angiogenic-osteogenic coupling is critical for successful bone repair. Therefore, this study harnesses the delivery of miR-210, known to be an activator of both angiogenesis and osteogenesis, and miR-16 inhibitor, as miR-16 is known to inhibit both pathways, from a collagen-nanohydroxyapatite scaffold system to rapidly enhance osteogenesis in vitro and bone repair in vivo in a rat calvarial defect model. Overall, it describes the successful development of the first dual-miRNA mimic/inhibitor scaffold for enhanced in vivo bone repair. This ‘off-the-shelf’ platform system offers immense potential to extend beyond bone applications and impact a myriad of other tissue engineering areas.

MiR-21 Participates in Anti-VEGF-Induced Epithelial Mesenchymal Transformation in RPE Cells.

To explore the role and possible mechanism of miR-21 in anti-VEGF drug-induced epithelial-mesenchymal transformation (EMT) in human retinal pigment epithelium (ARPE-19) cells, and to seek more therapeutic targets to improve prognosis vision. ARPE-19 cells were exposed to clinical dosage of bevacizumab and miR-21 expression was measured by real-time polymerase chain reaction (RT-PCR) assay. MiR-21 mimic and inhibitor were transfected into bevacizumab-induced ARPE-19, the expression of α-smooth muscle actin (α-SMA), E-cadherin, and SNAI1 were detected by cell immunofluorescence and Western blotting. Clinical dosage of bevacizumab caused EMT and enhanced miR-21 expression in ARPE-19 cells (P<0.05). The inhibition of miR-21 attenuated the EMT effect of bevacizumab, while overexpression of miR-21 promoted this activity (P<0.05). The SNAI1 was up-regulated by bevacizumab and promotion was partially suppressed by the miR-21 inhibitor and aggravated by the miR-21 mimic (P<0.05). MiR-21 promotes bevacizumab-induced EMT in ARPE cells which is significantly positively correlated with SNAI1. MiR-21 might be a potential miRNA-based therapeutic target for reducing bevacizumab-induced subretinal fibrosis.

Isovitexin alleviates hepatic fibrosis by regulating miR-21-mediated PI3K/Akt signaling and glutathione metabolic pathway: based on transcriptomics and metabolomics

BackgroundEffective drugs for the treatment of hepatic fibrosis have not yet been identified. Isovitexin (IVT) is a promising hepatoprotective agent owing to its efficacy against acute liver injury. However, the role of IVT in liver fibrosis has not been reported. PurposeTo explore the effect of IVT on liver fibrosis both in vitro and in vivo. Study design and methodsA mouse model of liver fibrosis induced by carbon tetrachloride (CCl4) and two types of hepatic stellate cell models induced by platelet-derived growth factor-BB (PDGF-BB) were established to evaluate the effect of IVT on hepatic fibrosis. Transcriptomics and metabolomics were used to predict the underlying targets of IVT and were validated by a combination of in vitro and in vivo experiments. Exploration of miRNA and N6-methyladenosine (m6A) modifications was also carried out to detect the key upstream targets of the above targets. ResultsIVT reduced collagen deposition and hepatic stellate cell activation to alleviate liver fibrosis. The transcriptomics and metabolomics analyses showed that phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling and the glutathione (GSH) metabolic pathway may be the main regulatory processes of IVT in hepatic fibrosis. Both the in vitro and in vivo experiments confirmed the inhibitory effect of IVT on the PTEN–PI3K–Akt–mTOR axis and activation of the GSH metabolic pathway. A miR-21 mimic inhibited the effects of IVT on these two pathways, suggesting that miR-21 is the hub for IVT regulation of PI3K–Akt signaling and the GSH metabolic pathway. IVT also increased pri-miR-21 level and reduced the m6A enrichment of pri-miR-21, demonstrating that IVT may regulate pri-miR-21 through m6A modification, thereby affecting the maturation of miR-21. ConclusionThis study is the first to propose a protective effect of IVT against liver fibrosis. The mechanism of IVT against hepatic fibrosis is based on the regulation of miR-21, targeting PTEN–Akt signaling and the GSH metabolic pathway, which is also a novel discovery.

Electroacupuncture Promotes Nerve Regeneration and Functional Recovery Through Regulating lncRNA GAS5 Targeting miR-21 After Sciatic Nerve Injury

Although the benefits of electroacupuncture (EA) for peripheral nerve injury (PNI) are well accepted in clinical practice, the underlying mechanism remains incompletely elucidated. In our study, we observed that EA intervention led to a reduction in the expression of the long non-coding RNA growth-arrest-specific transcript 5 (GAS5) and an increased in miR-21 levels within the injured nerve, effectively promoting functional recovery and nerve regeneration following sciatic nerve injury (SNI). In contrast, administration of adeno-associated virus expressing GAS5 (AAV-GAS5) weakened the therapeutic effect of EA. On the other hand, both silencing GAS5 and introducing a miR-21 mimic prominently enhanced the proliferation activity and migration ability of Schwann cells (SCs), while also inhibiting SCs apoptosis. On the contrary, inhibition of SCs apoptosis was found to be mediated by miR-21. Additionally, overexpression of GAS5 counteracted the effects of the miR-21 mimic on SCs. Moreover, SCs that transfected with the miR-21 mimic promoted neurite growth in hypoxia/reoxygenation-induced neurons, which might be prevented by overexpressing GAS5. Furthermore, GAS5 was found to be widely distributed in the cytoplasm and was negatively regulated by miR-21. Consequently, the targeting of GAS5 by miR-21 represents a potential mechanism through which EA enhances reinnervation and functional restoration following SNI. Mechanistically, the GAS5/miR-21 axis can modulate the proliferation, migration, and apoptosis of SCs while potentially influencing the neurite growth of neurons.

Antiviral effect of miR-155 in Epithelioma papulosum cyprini (EPC) cells against viral hemorrhagic septicemia virus (VHSV) infection.

MicroRNAs (miRNAs) are small non-coding RNAs known to play a significant role in the regulation of gene expression in various living organisms including fish. MiR-155 is known to enhance immunity in cells and several reports have demonstrated the antiviral properties of miR-155 in mammals. In this study, we investigated the antiviral role of miR-155 in Epithelioma papulosum cyprini (EPC) cells with viral hemorrhagic septicemia virus (VHSV) infection. EPC cells were transfected with miR-155 mimic and then infected with VHSV at different MOIs (0.01 and 0.001). The cytopathogenic effect (CPE) was observed at 0, 24, 48, and 72h post infection (h.p.i). CPE progression appeared at 48h.p.i in mock groups (VHSV only infected groups) and the VHSV infection group transfected with miR-155 inhibitors. On the other hand, the groups transfected with the miR-155 mimic did not show any CPE formation after infection with VHSV. The supernatant was collected at 24, 48 and 72h.p.i., and the viral titers were measured by plaque assay. The viral titers increased at 48 and 72h.p.i in groups infected only with VHSV. In contrast, the groups transfected with miR-155 did not show any increase in the virus titer and had a similar titer to 0h.p.i. Furthermore, the real-time RT-PCR of immune gene expression showed upregulation of Mx1 and ISG15 at 0, 24, and 48h.p.i in groups transfected with miR-155, while the genes were upregulated at 48h.p.i in groups infected only with VHSV. Based on these results, miR-155 can induce the overexpression of type I interferon-related immune genes in EPCs and inhibit the viral replication of VHSV. Therefore, these results suggest that miR-155 could possess an antiviral effect against VHSV.