Modulation of lncRNA NEAT1 overturns the macrophages based immune response in M. tuberculosis infected patients via miR-373 regulation

There is a lack of studies which explore and clarify the interactions that occur between host macrophage and Mycobacterium tuberculosis with regard to microRNA such as LNCNEAT1 and miR-373. The current study determines the mechanisms involved in the control of M. tuberculosis infection by macrophage using LNCNEAT1 and miR-373. The researchers collected different samples from healthy individuals, pulmonary TB patients, and samples like hMDMs cells and H37Rv infected MTB to determine the concentrations of inflammatory factors. The impact of NEAT1 and miR-373 upon macrophages was analyzed in NEAT1-specific siRNA (si-NEAT1), NEAT1 over-expression vector (pcDNA3.1-NEAT1), miR-373 mimic, miR-373 inhibitor (anti-miR-373), and negative control, and macrophages infected with H37Ra. The results inferred that among pulmonary TB patients, NEAT1 got heavily expressed while the expression level of miR-373 was poor. The number of inflammatory factors with pulmonary TB was notably higher. This got further amplified in macrophages after being infected with H37Ra, while no such observations found for miR-373. During post-transfection, low concentration of inflammatory factors was observed while the cells in si-NEAT1 group got proliferated in low volume compared to both pcDNA3.1-NEAT1 group and NEAT1 negative control group. However, the capability of apoptosis was higher compared to the other two groups (p < 0.05). There was an increase observed in inflammatory factors as well as proliferation in anti-miR-373 group compared to miR-373 mimics and miR-373-negative control group while a significant decline was observed in apoptosis. LNCNEAT1 aggravated the number of inflammatory factors in macrophages that got infected with MTB while on the other end, it mitigated both phagocytosis as well as the cellular immunity of macrophages. In addition to this, it enhanced the proliferation of infected cells and inhibited apoptosis via targeted regulation of miR-373, thus resulting in the development of TB.

miR-29b-3p regulates cardiomyocytes pyroptosis in CVB3-induced myocarditis through targeting DNMT3A

BACKGROUND

Viral myocarditis (VMC) is a disease resulting from viral infection, which manifests as inflammation of myocardial cells. Until now, the treatment of VMC is still a great challenge for clinicians. Increasing studies indicate the participation of miR-29b-3p in various diseases. According to the transcriptome sequencing analysis, miR-29b-3p was markedly upregulated in the viral myocarditis model. The purpose of this study was to investigate the role of miR-29b-3p in the progression of VMC.

METHODS

We used CVB3 to induce primary cardiomyocytes and mice to establish a model of viral myocarditis. The purity of primary cardiomyocytes was identified by immunofluorescence. The cardiac function of mice was detected by Vevo770 imaging system. The area of inflammatory infiltration in heart tissue was shown by hematoxylin and eosin (H&E) staining. The expression of miR-29b-3p and DNMT3A was detected by quantitative real time polymerase chain reaction (qRT-PCR). The expression of a series of pyroptosis-related proteins was detected by western blot. The role of miR-29b-3p/DNMT3A in CVB3-induced pyroptosis of cardiomyocytes was studied in this research.

RESULTS

Our data showed that the expression of miR-29b-3p was upregulated in CVB3-induced cardiomyocytes and heart tissues in mice. To explore the function of miR-29b-3p in CVB3-induced VMC, we conducted in vivo experiments by knocking down the expression of miR-29b-3p using antagomir. We then assessed the effects on mice body weight, histopathology changes, myocardial function, and cell pyroptosis in heart tissues. Additionally, we performed gain/loss-of-function experiments in vitro to measure the levels of pyroptosis in primary cardiomyocytes. Through bioinformatic analysis, we identified DNA methyltransferases 3A (DNMT3A) as a potential target gene of miR-29b-3p. Furthermore, we found that the expression of DNMT3A can be modulated by miR-29b-3p during CVB3 infection.

CONCLUSIONS

Our results demonstrate a correlation between the expression of DNMT3A and CVB3-induced pyroptosis in cardiomyocytes. These findings unveil a previously unidentified mechanism by which CVB3 induces cardiac injury through the regulation of miR-29b-3p/DNMT3A-mediated pyroptosis.

The phosphokinase activity of IRE1ɑ prevents the oxidative stress injury through miR-25/Nox4 pathway after ICH

BACKGROUND

Endoplasmic reticulum (ER) stress and oxidative stress are the major pathologies encountered after intracerebral hemorrhage (ICH). Inositol-requiring enzyme-1 alpha (IRE1α) is the most evolutionarily conserved ER stress sensor, which plays a role in monitoring and responding to the accumulation of unfolded/misfolded proteins in the ER lumen. Recent studies have shown that ER stress is profoundly related to oxidative stress in physiological or pathological conditions. The purpose of this study was to investigate the role of IRE1α in oxidative stress and the potential mechanism.

METHODS

A mouse model of ICH was established by autologous blood injection. The IRE1α phosphokinase inhibitor KIRA6 was administrated intranasally at 1 h after ICH, antagomiR-25 and agomiR-25 were injected intraventricularly at 24 h before ICH. Western blot analysis, RT-qPCR, immunofluorescence staining, hematoma volume, neurobehavioral tests, dihydroethidium (DHE) staining, H2O2 content, brain water content, body weight, Hematoxylin and Eosin (HE) staining, Nissl staining, Morris Water Maze (MWM) and Elevated Plus Maze (EPM) were performed.

RESULTS

Endogenous phosphorylated IRE1α (p-IRE1α), miR-25-3p, and Nox4 were increased in the ICH model. Administration of KIRA6 downregulated miR-25-3p expression, upregulated Nox4 expression, promoted the level of oxidative stress, increased hematoma volume, exacerbated brain edema and neurological deficits, reduced body weight, aggravated spatial learning and memory deficits, and increased anxiety levels. Then antagomiR-25 further upregulated the expression of Nox4, promoted the level of oxidative stress, increased hematoma volume, exacerbated brain edema and neurological deficits, whereas agomiR-25 reversed the effects promoted by KIRA6.

CONCLUSION

The IRE1α phosphokinase activity is involved in the oxidative stress response through miR-25/Nox4 pathway in the mouse ICH brain.

Effect of miR-1297 on Kidney Injury in Rats with Diabetic Nephropathy through the PTEN/PI3K/AKT Pathway

PURPOSE

This study aimed to determine the influence of miR-1297 on kidney injury in rats with diabetic nephropathy (DN) and its causal role.

METHODS

A DN rat model was established through right kidney resection and intraperitoneal injection of streptozotocin (STZ). Sham rats did not undergo right kidney resection or STZ injection. The DN rats were divided into the DN model and antagomiR-1297 treatment groups. Kidney morphology was observed using hematoxylin and eosin staining. Renal function indices, including blood urea nitrogen (BUN), serum creatinine (SCr), and urinary protein, were measured using kits. Levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1β, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) were determined through enzyme-linked immunosorbent assay (ELISA). Fibrin (FN), collagen type I (Col I), and α-smooth muscle actin (α-SMA) were assessed through western blotting and real-time reverse transcription-polymerase chain reaction. Apoptosis was detected using terminal deoxynucleotidyl transferase dUTP nick end labeling staining. miR-1297 targets were predicted using bioinformatic software and verified through luciferase reporter assay. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN)/phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway expression was analyzed through western blotting.

RESULTS

AntagomiR-1297 reduced BUN (p = 0.005), SCr (p = 0.012), and urine protein (p < 0.001) levels and improved kidney tissue morphology. It prevented renal interstitial fibrosis by decreasing FN, Col I, and α-SMA protein levels (all p < 0.001). AntagomiR-1297 increased SOD (p = 0.001) and GSH-Px (p = 0.002) levels. Additionally, it reduced levels of cell inflammatory factors, including TNF-α, IL-6, and IL-1β (all p < 0.001), and alleviated apoptosis (p < 0.001) in rat kidney tissue with DN. miR-1297 was pinpointed as a target for PTEN. AntagomiR-1297 increased PTEN expression and suppressed PI3K and AKT phosphorylation (all p < 0.001).

CONCLUSIONS

AntagomiR-1297 can mitigate renal fibrosis, renal inflammation, apoptosis, and oxidative stress levels through the PTEN/PI3K/AKT pathway.

Effects of miR-214 on adenosine A2A receptor and carboxymethyl chitosan nanoparticles on the function of keloid fibroblasts and their mechanisms

This work prepared and investigated the impact of carboxymethyl chitosan nanoparticles (MC-NPs) on the proliferative capability of keloid fibroblasts (KFBs) while analyzing the mechanistic roles of miR-214 and adenosine A2A receptor (A2AR) in fibroblasts within hypertrophic scars. MC-NPs were synthesized through ion cross-linking, were characterized using transmission electron microscopy (TEM) and laser particle size scattering. The influence of MC-NPs on the proliferation capacity of KFBs was assessed using the MTT method. Changes in the expression levels of miR-214 and A2AR in KFBs, normal skin fibroblasts (NFBs), hypertrophic scar tissue, and normal skin tissue were analyzed. KFBs were categorized into anti-miR-214, anti-miR-NC, miR-214 mimics, miR-NC, si-A2AR, si-con, anti-miR-214+ si-con, and anti-miR-214+ si-A2AR groups. Bioinformatics target prediction was conducted to explore the interaction between miR-214 and A2AR. Real-time quantitative PCR and immunoblotting (WB) were employed to detect the expression levels of miR-214, A2AR, apoptotic protein Bax, and TGF-β in different cells. Cell counting kit-8 (CCK8) and flow cytometry were employed to assess cell proliferation activity and apoptosis. The results indicated that MC-NPs exhibited spherical particles with an average diameter of 236.47 ± 4.98 nm. The cell OD value in the MC-NPs group was lower than that in KFBs (P < 0.05). The mRNA levels of miR-214 in KFBs and hypertrophic scar tissue were lower than those in NFBs and normal tissue (P < 0.001), while the mRNA and protein levels of A2AR were significantly elevated (P < 0.05). Compared to the control group and anti-miR-NC, the anti-miR-214 group showed significantly increased cell OD values and Bcl-2 protein expression (P < 0.001), decreased levels of apoptotic gene Bax protein, TGF-β gene mRNA, and protein expression (P < 0.001). Continuous complementary binding sites were identified between miR-214 and A2AR. Compared to the control group, the si-A2AR group exhibited a significant decrease in A2AR gene mRNA and protein expression levels (P < 0.001), reduced cell viability (P < 0.001), increased apoptosis rate (P < 0.001), and a significant elevation in TGF-β protein expression (P < 0.001). miR-214 targetedly regulated the expression of A2AR, inducing changes in TGF-β content, promoting the proliferation of keloid fibroblasts, and inhibiting cell apoptosis.

Enhancement of miR-16-5p on spinal cord injury-induced neuron apoptosis and inflammatory response through inactivating ERK1/2 pathway

BACKGROUND

The aim of this study was to explore the effect and mechanism of miR-16-5p on neuron apoptosis and inflammatory response induced by spinal cord injury (SCI).

METHODS

Allen's weight-drop method and Basso Bcattie Bresnahan (BBB) rating scale were used to establish SCI rat model and assess locomotor function, respectively. Histopathology of SCI rats and Sham-operated rats was validated by hematoxylin and eosin (H&E) staining. After intravenous injection of miR-16-5p agomir, miR-16-5p antagomir, pcDNA3.1-Apelin-13 or negative controls into SCI rat tails, neuron apoptosis and the expression of miR-16-5p, Apelin-13, apoptotic proteins, inflammatory response-related proteins, and ERK1/2 pathway-related protein were detected. Dual luciferase reporter gene assay was applied for identifying the binding between miR-16-5p and Apelin-13.

RESULTS

SCI rats had locomotor impairment with markedly edema and hemorrhage. Upregulated miR-16-5p expression and downregulated Apelin-13 expression were presented in SCI rats. Intravenous injection of miR-16-5p antagomir or/and pcDNA3.1-Apelin-13 could increase the expression of antiapoptotic proteins (Bcl-2 and Mcl-1) and p-ERK1/2 expression while decrease the expression of proapoptotic proteins (cleaved caspase-3 and Bax) and inflammatory response-related proteins (TNF-α, IL-1β and IL-6). The reverse pattern was shown in rats injected with miR-16-5p agomir. MiR-16-5p targeted Apelin-13. Promotion of miR-16-5p agomir on SCI was attenuated by injection of agomir + pcDNA3.1-Apelin-13.

CONCLUSIONS

Downregulation of miR-16-5p could upregulate Apelin-13 expression to activate ERK1/2 pathway, thus alleviating SCI-induced neuron apoptosis and inflammatory response.

Dexamethasone and MicroRNA-204 Inhibit Corneal Neovascularization

INTRODUCTION

This was an in vivo animal study designed to investigate the interaction between dexamethasone (Dex) and microRNA-204 (miR-204) in a mouse alkali burn-induced corneal neovascularization (CNV) model. The function of miR-204 was then investigated in human mammary epithelial cells (HMECs) in vitro.

MATERIALS AND METHODS

The CNV model was induced by corneal alkali burn in BLAB/c mice. The mice were randomly divided into five groups: normal control (Ctrl), alkali burn-induced corneal injury (Alkali), alkali burn + Dex (Dex), alkali burn + negative control (NTC), and alkali burn + miR-204 agomir (miR-204). Subconjunctival injection of NTC, Dex, or miR-204 agomir was conducted at 0, 3, and 6 days, respectively, after alkali burn. The corneas were collected at day 7 after injury, and the CNV area was observed using immunofluorescence staining. The expression of miR-204 was analyzed with quantitative real time (qRT)-PCR. In HMECs, exogenous miR-204 agomir or antagomir was used to strengthen or inhibit the expression of miR-204. Migration assays and tube formation studies were conducted to evaluate the function of miR-204 on HMECs.

RESULTS

At 7 days post-alkali burn, CNV grew aggressively into the cornea. MicroRNA-204 expression was reduced in the Alkali group in contrast with the Ctrl group (P = .003). However, miR-204 was upregulated in the Dex group (vs. alkali group, P = .008). The CNV areas in the NTC and miR-204 groups were 59.30 ± 8.32% and 25.60 ± 2.30%, respectively (P = .002). In vitro, miR-204 agomir showed obvious inhibition on HMEC migration in contrast with NTC (P = .033) and miR-204 antagomir (P = .017). Compared with NTC, miR-204 agomir attenuated tube formation, while miR-204 antagomir accelerated HMEC tube formation (P < .05).

CONCLUSION

The role of Dex in attenuating CNV may be partly attributed to miR-204. MiR-204 may be a potential therapeutic target in alkali burn-induced CNV.

Liposomal AntagomiR-155-5p Restores Anti-Inflammatory Macrophages and Improves Arthritis in Preclinical Models of Rheumatoid Arthritis

OBJECTIVE

We previously reported an increased expression of microRNA-155 (miR-155) in the blood monocytes of patients with rheumatoid arthritis (RA) that could be responsible for impaired monocyte polarization to anti-inflammatory M2-like macrophages. In this study, we employed two preclinical models of RA, collagen-induced arthritis and K/BxN serum transfer arthritis, to examine the therapeutic potential of antagomiR-155-5p entrapped within PEGylated (polyethylene glycol [PEG]) liposomes in resolution of arthritis and repolarization of monocytes towards the anti-inflammatory M2 phenotype.

METHODS

AntagomiR-155-5p or antagomiR-control were encapsulated in PEG liposomes of 100 nm in size and -10 mV in zeta potential with high antagomiR loading efficiency (above 80%). Mice were injected intravenously with 1.5 nmol/100 μL PEG liposomes containing antagomiR-155-5p or control after the induction of arthritis.

RESULTS

We demonstrated the biodistribution of fluorescently tagged PEG liposomes to inflamed joints one hour after the injection of fluorescently tagged PEG liposomes, as well as the liver's subsequent accumulation after 48 hours, indicative of hepatic clearance, in mice with arthritis. The injection of PEG liposomes containing antagomiR-155-5p decreased arthritis score and paw swelling compared with PEG liposomes containing antagomiR-control or the systemic delivery of free antagomiR-155-5p. Moreover, treatment with PEG liposomes containing antagomiR-155-5p led to the restoration of bone marrow monocyte defects in anti-inflammatory macrophage differentiation without any significant functional change in other immune cells, including splenic B and T cells.

CONCLUSION

The injection of antagomiR-155-5p encapsulated in PEG liposomes allows the delivery of small RNA to monocytes and macrophages and reduces joint inflammation in murine models of RA, providing a promising strategy in human disease.

MiR-184-5p represses neuropathic pain by regulating CCL1/CCR8 signaling interplay in the spinal cord in diabetic mice

BACKGROUND

Diabetic neuropathic pain (DNP) is a serious complication for diabetic patients involving nervous system. MicroRNAs (miRNAs) are small-noncoding RNAs which are dysregulated in neuropathic pain, and might be critical molecules for pain treatment. Our previous study has shown miR-184-5p was significantly downregulated in DNP. Therefore, the mechanism of miR-184-5p in DNP was investigated in this study.

METHODS

A DNP model was established through streptozotocin (STZ). The pharmacological tools were injected intrathecally, and pain behavior was evaluated by paw withdrawal mechanical thresholds (PWMTs). Bioinformatics analysis, Dual-luciferase reporter assay and fluorescence-in-situ-hybridization (FISH) were used to seek and confirm the potential target genes of miR-184-5p. The expression of relative genes and proteins was analyzed by quantitative reverse transcriptase real-time PCR (qPCR) and western blotting.

RESULTS

MiR-184-5p expression was down-regulated in spinal dorsal on days 7 and 14 after STZ, while intrathecal administration of miR-184-5p agomir attenuates neuropathic pain induced by DNP and intrathecal miR-184-5p antagomir induces pain behaviors in naïve mice. Chemokine CC motif ligand 1 (CCL1) was found to be a potential target of miR-184-5p and the protein expression of CCL1 and the mRNA expression of CCR8 were up-regulated in spinal dorsal on days 7 and 14 after STZ. The luciferase reporter assay and FISH demonstrated that CCL1 is a direct target of miR-184-5p. MiR-184-5p overexpression attenuated the expression of CCL1/CCR8 in DNP; intrathecal miR-184-5p antagomir increased the expression of CCL1/CCR8 in spinal dorsal of naïve mice.

CONCLUSION

This research illustrates that miR-184-5p alleviates DNP through the inhibition of CCL1/CCR8 signaling expression.

Mir324 knockout regulates the structure of dendritic spines and impairs hippocampal long-term potentiation

MicroRNAs are an emerging class of synaptic regulators. These small noncoding RNAs post-transcriptionally regulate gene expression, thereby altering neuronal pathways and shaping cell-to-cell communication. Their ability to rapidly alter gene expression and target multiple pathways makes them interesting candidates in the study of synaptic plasticity. Here, we demonstrate that the proconvulsive microRNA miR-324-5p regulates excitatory synapse structure and function in the hippocampus of mice. Both Mir324 knockout (KO) and miR-324-5p antagomir treatment significantly reduce dendritic spine density in the hippocampal CA1 subregion, and Mir324 KO, but not miR-324-5p antagomir treatment, shift dendritic spine morphology, reducing the proportion of thin, "unstable" spines. Western blot and quantitative Real-Time PCR revealed changes in protein and mRNA levels for potassium channels, cytoskeletal components, and synaptic markers, including MAP2 and Kv4.2, which are important for long-term potentiation (LTP). In line with these findings, slice electrophysiology revealed that LTP is severely impaired in Mir324 KO mice, while neurotransmitter release probability remains unchanged. Overall, this study demonstrates that miR-324-5p regulates dendritic spine density, morphology, and plasticity in the hippocampus, potentially via multiple cytoskeletal and synaptic modulators.

Contribution of skeletal muscle-specific microRNA-133b to insulin resistance in heart failure

Insulin resistance (IR) is one of the hallmarks of heart failure (HF). Abnormalities in skeletal muscle (SM) metabolism have been identified in patients with HF. However, the underlying mechanisms of IR development in SM in HF are poorly understood. Herein, we hypothesize that HF upregulates miR-133b in SM and in turn alters glucose metabolism and the propensity toward IR. Mitochondria isolated from SM of mice with HF induced by transverse aortic constriction (TAC) showed lower respiration and downregulation of muscle-specific components of the tricarboxylic acid (TCA) cycle, AMP deaminase 1 (AMPD1), and fumarate compared with those from control animals. RNA-Seq and subsequent qPCR validation confirmed upregulation of SM-specific microRNA (miRNA), miR-133b, in TAC versus sham animals. miR-133b overexpression alone resulted in significantly lower mitochondrial respiration, cellular glucose uptake, and glycolysis along with lower ATP production and cellular energy reserve compared with the scramble (Scr) in C2C12 cells. miR-133b binds to the 3'-untranslated region (UTR) of KLF15, the transcription factor for the insulin-sensitive glucose transporter, GLUT4. Overexpression of miR-133b lowers GLUT4 and lowers pAkt in presence of insulin in C2C12 cells. Finally, lowering miR-133b in primary skeletal myocytes isolated from TAC mice using antagomir-133b reversed the changes in KLF15, GLUT4, and AMPD1 compared with the scramble-transfected myocytes. Taken together, these data demonstrate a role for SM miR-133b in altered glucose metabolism in HF and suggest the therapeutic potential in HF to improve glucose uptake and glycolysis by restoring GLUT4 abundance. The data uncover a novel mechanism for IR and ultimately SM metabolic abnormalities in patients with HF.NEW & NOTEWORTHY Heart failure is associated with systemic insulin resistance and abnormalities in glucose metabolism but the underlying mechanisms are poorly understood. In the skeletal muscle, the major peripheral site of glucose utilization, we observe an increase in miR-133b in heart failure mice, which reduces the insulin-sensitive glucose transporter (GLUT4), glucose uptake, and metabolism in C2C12 and in myocytes. The antagomir for miR-133b restores GLUT4 protein and markers of metabolism in skeletal myocytes from heart failure mice demonstrating that miR-133b is an exciting target for systemic insulin resistance in heart failure and an important player in the cross talk between the heart and the periphery in the heart failure syndrome.

Upregulation of miR-151-5p promotes the apoptosis of intestinal epithelial cells by targeting brain-derived neurotrophic factor in ulcerative colitis mice

Ulcerative colitis (UC) is the most prevalent form of chronic inflammatory bowel disease, the etiology of which is poorly understood. This study investigated the role of miR-151-5p on UC and explored the role of brain-derived neurotrophic factor (BDNF) in a UC mouse model and cell model. A UC mouse model was engineered by dextran sulfate sodium (DSS) induction. Primary mouse intestinal epithelial cells (IECs) were isolated. Colitis mice were intraperitoneally injected with miR-151-5p antagomir and antagomir negative control, and weight loss, disease activity index, and colon length of mice were measured. Colon tissues of mice were histologically analyzed. A UC cell model was constructed by treating MODE-K cells with DSS. miR-151-5p expression in the cell model was modulated by transfection. The exogenous BDNF effect on the UC cell model and intestinal cell apoptosis, viability and proliferation was detected by flow cytometry, CCK-8 and EdU experiment. The expression of miR-151-5p and apoptosis-related proteins was assessed through q-PCR and western blotting. miR-151-5p was upregulated in the colon tissues and primary IECs of colitis mice. miR-151-5p directly inhibited the expression of BNDF. miR-151-5p upregulation promoted apoptosis in UC MODE-K cells. miR-151-5p upregulation repressed the viability of UC MODE-K cells. Exogenous BNDF treatment reversed the effect of miR-151-5p on UC MODE-K cells. miR-151-5p knockdown improved UC symptoms in mice, including alleviating weight loss, reducing disease activity index and improving colon length and damaged colon tissues. miR-151-5p contributed to intestinal epithelial cells apoptosis in colitis mice via inhibiting BNDF expression.

[Down-regulation of miR-29a inhibits mitochondrial fusion and fission in rat H9c2 cardiomyocytes induced by oxygen and glucose deprivation/reoxygenation]

Objective To investigate the effect of miR-29a interference on mitochondrial fusion and fission of cardiomyocytes induced by oxygen and glucose deprivation/reoxygenation (OGD/R). Methods H9c2 cells were divided into normal control group, model group, negative control group and miR-29a interference group. Rat H9c2 cardiomyocyte injury model was induced by OGD/R. Negative control (NC) group cells were transfected with anti-NC, while miR-29a interference group cells were transfected with anti-miR-29a, and normal control group cells were not transfected. Reverse transcription PCR was used to detect miR-29a interference efficiency, along with CCK-8 assay to detect cell proliferation ratio, flow cytometry to detect cell apoptosis rate and mitochondrial membrane potential change, and kit to detect superoxide dismutase(SOD), malondialdehyde (MDA), lactate dehydrogenase (LDH)contents. Western blot analysis was employed to test the levels of Bcl2-associated X protein (BAX), Bcl2 antagonist/killer (BAK), caspase-9, mitochondrial fission protein 1(Fis1), mitofusin 1 (Mfn1), Mfn2, optic atrophy 1(OPA1), phosphoryerated extracellular signal-regulated kinase (p-ERK) and phosphoryerated dynamin related protein-1(p-Drp1). Results Compared with OGD/R group, the expression level of miR-29a of H9c2 cells in OGD/R group treated with anti-miR-29a decreased significantly, together with the findings including significantly increased cell proliferation factor, decreased apoptosis rate, increased SOD content, decreased MDA and LDH contents, as well as significantly increased mitochondrial membrane potential. The protein levels of BAX, BAK, caspase-9, Fis1, Mfn1, Mfn2, OPA1, p-ERK and p-Drp1 significantly decreased. Conclusion Interference with miR-29a expression can promote OGD/R-induced proliferation of H9c2 cells, inhibit cell apoptosis, reduce mitochondrial oxidative stress level, enhance mitochondrial membrane potential, and alleviate mitochondrial over-fusion and fission of myocardial cells.

miR-409-3p Regulated by GATA2 Promotes Cardiac Fibrosis through Targeting Gpd1

Cardiac fibrosis is a hallmark of numerous chronic cardiovascular diseases that leads to heart failure. However, there is no validated therapy for it. Dysregulation of microRNAs has been confirmed to be involved in cardiac fibrosis development. However, the regulatory network was not well explored. This study was the first to highlight the role and molecular mechanism of miR-409-3p in cardiac fibrosis. We found that miR-409-3p was consistently increased in three fibrotic models, including heart tissues of postmyocardial infarction (MI) mice and neonatal rat cardiac fibroblasts treated with angiotensin II (Ang II) or transforming growth factor-β (TGF-β). Furthermore, myocardial infarction surgery-induced cardiac fibrosis and dysfunction were attenuated by systemic delivery of miR-409-3p antagomir. Notably, transfection with miR-409-3p mimics promoted the proliferation of cardiac fibroblasts and fibroblast-to-myofibroblast differentiation, accompanied by upregulated expression of Col1a1, Col3a1, and α-SMA. On the contrary, the miR-409-3p inhibitor exhibited the opposite effect. Following this, we verified Gpd1 as a direct target of miR-409-3p. Gpd1 siRNA abolished the antifibrotic effect of miR-409-3p inhibitor in neonatal rat cardiac fibroblasts, suggesting that miR-409-3p promotes cardiac fibrosis at least partially through Gpd1. Moreover, GATA2 was identified as a cardiac fibrosis-associated upstream positive transcription factor of miR-409-3p. Finally, these findings suggest that modulating miR-409-3p could be a potential therapeutic method for cardiac fibrosis.

[lncRNA-HOTAIR inhibits the proliferation of H9c2 rat cardiomyocytes induced by lipopolysaccharide and promotes inflammation through targeting negative regulation of miR-1-3p]

Objective To investigate whether long non-coding RNA-HOX transcript antisense intergenic RNA (lncRNA-HOTAIR) regulates the inflammatory response of sepsis by targeting microRNA miR-1-3p. Methods 0.5 μg/mL lipopolysaccharide (LPS) was used to induce cardiomyocytes of H9c2 rats to establish a septic cardiomyocyte injury model. H9c2 cells were divided into control group, LPS group, and LPS combined with HOTAIR small interfering RNA negative control (si-NC) group, LPS combined with HOTAIR small interfering RNA (si-HOTAIR) group, LPS combined with miR-1-3p negative control (miR-NC) group, LPS combined with miR-1-3p group, LPS combined with si-HOTAIR and miR-1-3p inhibitor negative (anti-miR-NC) group, and LPS combined with siHOTAIR and anti-miR-1-3p group. Real-time quantitative PCR was used to determine the expression of HOTAIR and miR-1-3p, CCK-8 assay was used to detect cell proliferation, and Western blotting was used to analyze antigen KI-67 (ki67), P21, B-cell lymphoma 2 (Bcl2), Bcl2-related X protein (BAX) protein expression. Flow cytometry was performed to evaluate cell apoptosis. ELISA was used to determine the inflammatory factor interleukin 6(IL-6) and tumor necrosis factor-α (TNF-α) levels. The dual luciferase report experiment analyzes the targeting relationship between HOTAIR and miR-1-3p. Results The expression of HOTAIR in H9c2 cells of the LPS group was higher than that of the control group, and the expression of miR-1-3p was lower than that of the control group. Compared with the LPS combined with si-NC group, the LPS combined with si-HOTAIR treated H9c2 cell proliferation activity, presenting increased ki67 and Bcl2 expression, as well as decreased level of P21 expression, apoptosis rate, BAX expression, IL-6 and TNF-α. HOTAIR targets and regulates the expression of miR-1-3p. Compared with the LPS combined miR-1-3p group, the proliferation activity, ki67, Bcl2 expression of H9c2 cells increased in the LPS combined miR-NC group, and the P21 expression, apoptosis rate, BAX expression, IL-6, and TNF-α levels decreased. Compared with the LPS combined with si-HOTAIR and anti-miR-NC group, the H9c2 cell proliferation activity in the LPS combined with siHOTAIR and anti-miR-1-3p group descended, and the expression of ki67 and Bcl2 decreased, while the expression of P21, BAX, apoptosis, IL-6 and TNF-α levels increased. Conclusion HOTAIR negatively regulates the expression of miR-1-3p, inhibits LPS-induced cardiomyocyte H9c2 proliferation, and induces cell apoptosis and inflammation.

Extracellular Vesicles Regulate Sympatho-Excitation by Nrf2 in Heart Failure

BACKGROUND

Chronic heart failure (CHF) is associated with redox imbalance. Downregulation of Nrf2 (nuclear factor [erythroid-derived 2]-like 2) plays important roles in disrupting myocardial redox homeostasis and mediating sympathetic nerve activity in the setting of CHF. However, it is unclear if circulating extracellular vesicles (EVs) elicit sympathetic excitation in CHF by disrupting central redox homeostasis. We tested the hypothesis that cardiac-derived EVs circulate to the presympathetic rostral ventrolateral medulla and contribute to oxidative stress and sympathetic excitation via EV-enriched microRNA-mediated Nrf2 downregulation.

METHODS

Data were collected on rats with CHF post-myocardial infarction (MI) and on human subjects with ischemic CHF. EVs were isolated from tissue and plasma, and we determined the miRNAs cargo that related to targeting Nrf2 translation. We tracked the distribution of cardiac-derived EVs using in vitro labeled circulating EVs and cardiac-specific membrane GFP+ transgenic mice. Finally, we tested the impact of exogenously loading of antagomirs to specific Nrf2-related miRNAs on CHF-EV-induced pathophysiological phenotypes in normal rats (eg, sympathetic and cardiac function).

RESULTS

Nrf2 downregulation in CHF rats was associated with an upregulation of Nrf2-targeting miRNAs, which were abundant in cardiac-derived and circulating EVs from rats and humans. EVs isolated from the brain of CHF rats were also enriched with Nrf2-targeting miRNAs and cardiac-specific miRNAs. Cardiac-derived EVs were taken up by neurons in the rostral ventrolateral medulla. The administration of cardiac-derived and circulating EVs from CHF rats into the rostral ventrolateral medulla of normal rats evoked an increase in renal sympathetic nerve activity and plasma norepinephrine compared with Sham-operated rats, which were attenuated by exogenously preloading CHF-EVs with antagomirs to Nrf2-targeting miRNAs.

CONCLUSIONS

Cardiac microRNA-enriched EVs from animals with CHF can mediate crosstalk between the heart and the brain in the regulation of sympathetic outflow by targeting the Nrf2/antioxidant signaling pathway. This new endocrine signaling pathway regulating sympathetic outflow in CHF may be exploited for novel therapeutics.

[Resveratrol pretreatment improves mitochondrial function and alleviates myocardial ischemia-reperfusion injury by up-regulating mi R-20b-5p to inhibit STIM2]

This study aimed to explore the mechanism of resveratrol(RES) pretreatment in improving mitochondrial function and alleviating myocardial ischemia-reperfusion(IR) injury by inhibiting stromal interaction molecule 2(STIM2) through microRNA-20 b-5 p(miR-20 b-5 p). Ninety rats were randomly assigned into sham group, IR group, IR+RES(50 mg·kg~(-1) RES) group, IR+RES+antagomir NC(50 mg·kg~(-1) RES+80 mg·kg~(-1) antagomir NC) group, and IR+RES+miR-20 b-5 p antagomir(50 mg·kg~(-1) RES+80 mg·kg~(-1) miR-20 b-5 p antagomir) group, with 18 rats/group. The IR rat model was established by ligation of the left anterior descending coronary artery. Two weeks before the operation, rats in the IR+RES group were intraperitoneally injected with 50 mg·kg~(-1) RES, and those in the sham and IR groups were injected with the same dose of normal saline, once a day. Ultrasonic instrument was used to detect the left ventricular internal diameter at end-diastole(LVIDd) and left ventricular internal diameter at end-systole(LVIDs) of rats in each group. The 2,3,5-triphenyte-trazoliumchloride(TTC) method and hematoxylin-eosin(HE) staining were employed to detect the myocardial infarction area and histopathology, respectively. Real-time quantitative PCR(qRT-PCR) was carried out to detect the expression of miR-20 b-5 p in myocardial tissue. Oxygen glucose deprivation/reoxygenation(OGD/R) was performed to establish an OGD/R model of H9 c2 cardiomyocytes. CCK-8 assay was employed to detect H9 c2 cell viability. H9 c2 cells were assigned into the control group, OGD/R group, OGD/R+RES group(25 μmol·L~(-1)), OGD/R+RES+inhibitor NC group, OGD/R+RES+miR-20 b-5 p inhibitor group, mimic NC group, miR-20 b-5 p mimic group, inhibitor NC group, and miR-20 b-5 p inhibitor group. Flow cytometry was employed to detect cell apoptosis. Western blot was employed to detect the expression of B-cell lymphoma-2(Bcl-2), Bcl-2-associated X protein(Bax), cleaved-cysteine proteinase 3(cleaved-caspase-3), and STIM2 in cells. The mitochondrial membrane potential(MMP) assay kit, reactive oxygen species(ROS) assay kit, and adenosine triphosphate(ATP) assay kit were used to detect the MMP, ROS, and ATP levels, respectively. Dual luciferase reporter gene assay was adopted to verify the targeting relationship between miR-20 b-5 p and STIM2. Compared with the sham group, the modeling of IR increased the myocardial infarction area, LVIDd, LVIDs, and myocardial pathology and down-regulated the expression of miR-20 b-5 p(P&lt;0.05). These changes were alleviated in the IR+RES group(P&lt;0.05). The IR+RES+miR-20 b-5 p antagomir group had higher myocardial infarction area, LVIDd, LVIDs, and myocardial pathology and lower expression of miR-20 b-5 p than the IR+RES group(P&lt;0.05). The OGD/R group had lower viability of H9 c2 cells than the control group(P&lt;0.05) and the OGD/R+RES groups(25, 50, and 100 μmol·L~(-1))(P&lt;0.05). Additionally, the OGD/R group had higher H9 c2 cell apoptosis rate, protein levels of Bax and cleaved caspase-3, and ROS level and lower Bcl-2 protein, MMP, and ATP levels than the control group(P&lt;0.05) and the OGD/R+RES group(P&lt;0.05). The OGD/R+RES+miR-20 b-5 p inhibitor group had higher H9 c2 cell apoptosis rate, protein levels of Bax and cleaved-caspase 3, and ROS level and lower Bcl-2 protein, MMP, and ATP levels than the OGD/R+RES group(P&lt;0.05). miR-20 b-5 p had a targeting relationship with STIM2. The expression of STIM2 was lower in the miR-20 b-5 p mimic group than in the mimic NC group(P&lt;0.05) and lower in the inhibitor NC group than in the miR-20 b-5 p inhibitor group(P&lt;0.05). RES pretreatment can inhibit the expression of STIM2 by promoting the expression of miR-20 b-5 p, thereby improving the function of mitochondria and alleviating myocardial IR damage.

Effect of circPUM1 on radioresistance of cervical cancer cells through targeting miR-144-3p

OBJECTIVE

To investigate the effect of circular RNA pumilio RNA binding family member (circPUM) 1 on radioresistance of cervical cancer cells and its mechanism.

METHODS

Cancer tissue and corresponding paricancerous tissue samples were collected from 47 patients with cervical cancer who underwent surgical treatment in the Second Affiliated Hospital of Zhengzhou University from August 2019 to February 2020. The expression levels of circPUM1 and miR-144-3p in cervical cancer tissues and paricancerous tissues were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The Pearson method was used to analyze the correlation between circPUM1 and miR-144-3p expression in cervical cancer tissues. circPUM1 lentiviral short hairpin RNA (sh-circPUM1) and its negative control (sh-NC), miR-144-3p oligonucleotide mimic (miR-144-3p mimic) and its negative control (miR-NC), sh-circPUM1 and miR-144-3p inhibitor (anti-miR), and sh-circPUM1 and anti-miR negative control (anti-miR-NC) were transfected into human cervical carcinoma SiHa cells, respectively, and the cells were irradiated with 0 and 4 Gy irradiation doses. Cell proliferation, colony formation, apoptosis, migration and invasion were detected by cell counting kit (CCK-8 method), plate colony formation assay, flow cytometry and Transwell assay, respectively. The protein expression of cleaved-caspase3 was detected by Western blotting. The targeting relationship between circPUM1 and miR-144-3p was analyzed with Starbase platform.

RESULTS

Compared with adjacent tissue, the expression of circPUM1 in cervical cancer tissue was significantly increased ( P<0.05), while the expression of miR-144-3p was decreased ( P<0.05). The circPUM1 was negatively correlated with miR-144-3p ( r=-0.9282, P<0.01). After transfection with sh-circPUM1 or miR-144-3p mimic, the inhibition rate of cell proliferation, the rate of apoptosis and the expression level of cleaved-caspase3 protein increased (all P<0.05), while the number of colonies formed, migrated and invaded cells decreased (all P<0.05). CircPUM1 could targeted to miR-144-3p. After co-transfection of sh-circPUM1 and anti-miR, the inhibition rate of cell proliferation, the rate of apoptosis and the expression level of cleaved-caspase3 protein significantly decreased (all P<0.05), while the number of colonies formed, migrated and invaded cells increased (all P<0.05).

CONCLUSION

Silencing circPUM1 may inhibit the proliferation, colony formation, migration, invasion and induce apoptosis of cervical cancer cells through targeting and regulating the expression of miR-144-3p.

miR-148a targets XBP1 to regulate trophoblast apoptosis induced by plasma reticulum stress in preeclampsia

To study the relationship between miR-148a and preeclampsia (PE), and clarify that miR-148a can regulate the endoplasmic reticulum stress (ERS) of placental trophoblasts by targeting the ERS protein X box binding protein 1 (XBP1).Fifty patients with hypertension during pregnancy, patients with mild PE, patients with severe PE, and normal pregnant women were selected, and their placental tissues were collected. RT-polymerase chain reaction was used to detect the expression of miR-148a in placental tissues, and Western blot was used to detect XBP1 in placental tissues. Compare the expression differences of miR-148a and XBP1 in each group, and analyze the correlation between the expressions of the two.Compared with the Neg-miR group, MTT experiment result in pre-miR-148a group was decreased. MTT experiment result in anti-miR-148a group was increased. Cell cycle test result in pre-miR-148a group [G1 (%)] was increased. Cell cycle test result in anti-miR-148a group [S (%)] was increased. Apoptosis test result in pre-miR-148a group [early apoptotic cells (%), late apoptotic cells (%)] was increased. Apoptosis test result in anti-miR-148a group [early apoptotic cells (%), late apoptotic cells (%)] was decreased. XBP1 expression result in pre-miR-148a group was increased. XBP1 expression result in anti-miR-148a group was decreased. Compared with the normal population, XBP1 is expressed in hypertension, mild eclampsia, severe eclampsia increased. GRP78, CHOP, and caspase-12 expression result in pre-miR-148a group was increased. GRP78, CHOP, and caspase-12 expression result in anti-miR-148a group was decreased.miR-148a can regulate the ERS-mediated apoptosis by targeting XBP1, thereby intervening in the occurrence and development of PE.

Mechanism of chlorogenic acid reducing lipopolysaccharideinduced acute lung injury in mice by regulating miR223/NLRP3 axis

OBJECTIVES

Chlorogenic acid has various physiological activities such as antibacterial, anti-inflammatory, and antiviral activities. Studies have shown that chlorogenic acid can alleviate the inflammatory response of mice with acute lung injury (ALI), but the specific mechanism is still unclear. This study aims to investigate whether chlorogenic acid attenuates lipopolysaccharide (LPS)-induced ALI in mice by regulating the microRNA-223 (miR-223)/nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) axis.

METHODS

SPF grade BALBc male mice were randomly divided into a control group, a model group, a chlorogenic acid group, a chlorogenic acid+miR-223 negative control (miR-223 NC) group, and a chlorogenic acid+miR-223 inhibitor (miR-223 antagomir) group, 10 mice in each group. Except the control group, the other groups were instilled with 4 mg/kg LPS through the airway to establish the ALI mouse model. After the modeling, the mice in the chlorogenic acid group were continuously given chlorogenic acid (100 mg/kg) by gavage for 7 d. The chlorogenic acid+miR-223 NC group and the chlorogenic acid+miR-223 antagomir group were given 100 mg/kg chlorogenic acid by gavage every day, and then were injected with 10 μL of miR-223 NC (0.5 nmol/μL) and miR-223 antagomir (0.5 nmol/μL) respectively for 7 consecutive days.The control group and the model group were replaced with normal saline. The lung tissues of mice were taken to measure the ratios of lung wet to dry weight (W/D). The bronchoalveolar lavage fluid of mice was collected to measure the levels of TNF-α, IL-6, and IL-1β by ELISA kit and to count the number of eosinophils (EOS), lymphocytes, neutrophils under light microscope. After HE staining, the pathological changes of lung tissues were observed and lung injury was scored. qRT-PCR method were used to determine the expression levels of miR-223 in lung tissues. Western blotting was used to determine the expression levels of NLRP3 protein in mouse lung tissues. Luciferase reporter assay was used to analyze the targeting relationship of miR-223 to NLRP3.

RESULTS

Compared with the control group, the lung W/D value, the lung injury score and the level of inflammatory factors in the bronchoalveolar lavage fluid were significantly increased in the model group (all P<0.05); the infiltration of inflammatory cells in the lung tissue was severe; the alveolar space was significantly increased; the alveolar wall was significantly thickened; the number of EOS, lymphocytes, and neutrophils in the bronchoalveolar lavage fluid was significantly increased (all P<0.05); the expression levels of miR-223 in lung tissue were significantly decreased (P<0.05); and the protein expression levels of NLRP3 were significantly increased (P<0.05). Compared with the model group, the W/D value of lungs, lung injury score, and levels of inflammatory factors in bronchoalveolar lavage fluid were significantly decreased in the chlorogenic acid group, the chlorogenic acid+miR-223 NC group, and the chlorogenic acid+miR-223 antagomir group (all P<0.05); lung tissues damage was alleviated; the numbers of EOS, lymphocytes, and neutrophils in bronchoalveolar lavage fluid were significantly decreased (all P<0.05); the expression levels of miR-223 in lung tissues were significantly increased (P<0.05); and the expression levels of NLRP3 protein were significantly decreased (P<0.05). Compared with the chlorogenic acid group, the lung W/D value, lung injury score, and inflammatory factor levels in the bronchoalveolar lavage fluid were significantly increased in the chlorogenic acid+miR-223 antagomir group (all P<0.05); lung tissue damage was aggravated; the number of EOS, lymphocytes and neutrophils in bronchoalveolar lavage fluid significantly increased (all P<0.05); the expression levels of miR-223 in lung tissues were significantly decreased (P<0.05); and the expression levels of NLRP3 protein were significantly increased (P<0.05). The results of luciferase reporter assay showed that miR-223 had a targeting relationship with NLRP3.

CONCLUSIONS

Chlorogenic acid may increase the level of miR-223, target the inhibition of NLRP3 expression, reduce LPS-induced inflammatory response in ALI mice, and alleviate pathological damage of lung tissues.

Temporal analysis of microRNAs associated with wing development in the English grain aphid, Sitobion avenae (F.) (Homoptera: Aphidiae)

Molecular mechanisms underlying wing evolution and development have been a point of scientific inquiry for decades. Phloem-feeding aphids are one of the most devastating global insect pests, where dispersal of winged morphs lead to annual movements, migrations, and range expansions. Aphids show a polyphenic wing dimorphism trait, and offer a model to study the role of environment in determining morphological plasticity of a single genotype. Despite recent progresses in the genetic understanding of wing polyphenism, the influence of environmental cues remains unclear. To investigate the involvement of miRNAs in wing development, we sequenced small RNA libraries of the English grain aphid, Sitobion avenae (F.) across six different developmental stages. As a result, we identified 113 conserved and 193 S. avenae-specific miRNAs. Gene Ontology and KEGG pathway analyses of putative target mRNAs for the six differentially expressed miRNAs are enriched for wing development processes. Dietary uptake of miR-263a, miR-316, and miR-184a agomirs and antagomirs led to significantly higher mortality (>70%) and a lower proportion of winged morphs (<5%). On the other hand, wing malformation was observed in miR-2 and miR-306 agomirs and miR-2 and miR-14 antagomirs, respectively, suggesting their involvement in S. avenae wing morphogenesis. These combined results not only shed light on the regulatory role of miRNAs in wing dimorphism, but also provide potential novel targets for the long-term sustainable management of S. avenae, a devastating global grain pest.

SARS-CoV-2 RNA elements share human sequence identity and upregulate hyaluronan via NamiRNA-enhancer network

BACKGROUND

Since late 2019, SARS-CoV-2 infection has resulted in COVID-19 accompanied by diverse clinical manifestations. However, the underlying mechanism of how SARS-CoV-2 interacts with host and develops multiple symptoms is largely unexplored.

METHODS

Bioinformatics analysis determined the sequence similarity between SARS-CoV-2 and human genomes. Diverse fragments of SARS-CoV-2 genome containing Human Identical Sequences (HIS) were cloned into the lentiviral vector. HEK293T, MRC5 and HUVEC were infected with laboratory-packaged lentivirus or transfected with plasmids or antagomirs for HIS. Quantitative RT-PCR and chromatin immunoprecipitation assay detected gene expression and H3K27ac enrichment, respectively. UV-Vis spectroscopy assessed the interaction between HIS and their target locus. Enzyme-linked immunosorbent assay evaluated the hyaluronan (HA) levels of culture supernatant and plasma of COVID-19 patients.

FINDINGS

Five short sequences (24-27 nt length) sharing identity between SARS-CoV-2 and human genome were identified. These RNA elements were highly conserved in primates. The genomic fragments containing HIS were predicted to form hairpin structures in silico similar to miRNA precursors. HIS may function through direct genomic interaction leading to activation of host enhancers, and upregulation of adjacent and distant genes, including cytokine genes and hyaluronan synthase 2 (HAS2). HIS antagomirs and Cas13d-mediated HIS degradation reduced HAS2 expression. Severe COVID-19 patients displayed decreased lymphocytes and elevated D-dimer, and C-reactive proteins, as well as increased plasma hyaluronan. Hymecromone inhibited hyaluronan production in vitro, and thus could be further investigated as a therapeutic option for preventing severe outcome in COVID-19 patients.

INTERPRETATION

HIS of SARS-CoV-2 could promote COVID-19 progression by upregulating hyaluronan, providing novel targets for treatment.

FUNDING

The National Key R&D Program of China (2018YFC1005004), Major Special Projects of Basic Research of Shanghai Science and Technology Commission (18JC1411101), and the National Natural Science Foundation of China (31872814, 32000505).

A new player in the game: treatment with antagomiR-21a-5p significantly attenuates histological and echocardiographic effects of experimental autoimmune myocarditis

AIMS

Myocarditis is associated with formidable symptoms and increased risk of adverse outcomes. Current approaches mostly rely on symptomatic treatments, warranting novel concepts for clinical practice. The aim of this study was to investigate the microRNA (miRNA) expression profile of Balb/c mice with experimental autoimmune myocarditis (EAM), choose a representative miRNA to antagonize after review of available literature and test its effects on myocardial inflammation in vitro and in vivo.

METHODS AND RESULTS

Phase 1: EAM was induced in 12 male Balb/c mice, 10 animals served as controls. After sacrifice, next-generation sequencing (NGS) of the miRNA expression profile was performed. Based on these results, H9C2 cells and human ventricular cardiac fibroblasts exposed to lipopolysaccharide (LPS) were treated with the selected candidate antagomiR-21a-5p. Phase 2: EAM was induced in 48 animals. Thereof, 24 animals were either treated with antagomiR-21a-5p or negative control oligonucleotide in a nanoparticle formulation. Transthoracic echocardiography (TTE) was performed on Days 0, 7, 14, and 21. Histopathological examination was performed after sacrifice. Phase 1: EAM resulted in a significant up-regulation of 27 miRNAs, including miR-21a-5p (log2FC: 2.23, adj. P = 0.0026). Transfection with antagomiR-21a-5p resulted in a significant reduction of TNFα, IL-6, and collagen I in vitro. Phase 2: Treatment with antagomiR-21a-5p, formulated in polymeric nanoparticles for systemic injection, significantly attenuated myocardial inflammation (P = 0.001) and fibrosis (P = 0.013), as well as myocardial 'hypertrophy' on TTE.

CONCLUSIONS

Silencing of miR-21a-5p results in a significant reduction of the expression of pro-inflammatory cytokines in vitro, as well as a significant attenuation of inflammation, fibrosis and echocardiographic effects of EAM in vivo.

3D hESC exosomes enriched with miR-6766-3p ameliorates liver fibrosis by attenuating activated stellate cells through targeting the TGFβRII-SMADS pathway

BACKGROUND

Exosomes secreted from stem cells exerted salutary effects on the fibrotic liver. Herein, the roles of exosomes derived from human embryonic stem cell (hESC) in anti-fibrosis were extensively investigated. Compared with two-dimensional (2D) culture, the clinical and biological relevance of three-dimensional (3D) cell spheroids were greater because of their higher regeneration potential since they behave more like cells in vivo. In our study, exosomes derived from 3D human embryonic stem cells (hESC) spheroids and the monolayer (2D) hESCs were collected and compared the therapeutic potential for fibrotic liver in vitro and in vivo.

RESULTS

In vitro, PKH26 labeled-hESC-Exosomes were shown to be internalized and integrated into TGFβ-activated-LX2 cells, and reduced the expression of profibrogenic markers, thereby regulating cellular phenotypes. TPEF imaging indicated that PKH26-labeled-3D-hESC-Exsomes possessed an enhanced capacity to accumulate in the livers and exhibited more dramatic therapeutic potential in the injured livers of fibrosis mouse model. 3D-hESC-Exosomes decreased profibrogenic markers and liver injury markers, and improved the level of liver functioning proteins, eventually restoring liver function of fibrosis mice. miRNA array revealed a significant enrichment of miR-6766-3p in 3D-hESC-Exosomes, moreover, bioinformatics and dual luciferase reporter assay identified and confirmed the TGFβRII gene as the target of miR-6766-3p. Furthermore, the delivery of miR-6766-3p into activated-LX2 cells decreased cell proliferation, chemotaxis and profibrotic effects, and further investigation demonstrated that the expression of target gene TGFβRII and its downstream SMADs proteins, especially phosphorylated protein p-SMAD2/3 was also notably down-regulated by miR-6766-3p. These findings unveiled that miR-6766-3p in 3D-hESC-Exosomes inactivated SMADs signaling by inhibiting TGFβRII expression, consequently attenuating stellate cell activation and suppressing liver fibrosis.

CONCLUSIONS

Our results showed that miR-6766-3p in the 3D-hESC-Exosomes inactivates smads signaling by restraining TGFβRII expression, attenuated LX2 cell activation and suppressed liver fibrosis, suggesting that 3D-hESC-Exosome enriched-miR-6766-3p is a novel anti-fibrotic therapeutics for treating chronic liver disease. These results also proposed a significant strategy that 3D-Exo could be used as natural nanoparticles to rescue liver injury via delivering antifibrotic miR-6766-3p.

MicroRNA-124 Alleviates Retinal Vasoregression via Regulating Microglial Polarization

Microglial activation is implicated in retinal vasoregression of the neurodegenerative ciliopathy-associated disease rat model (i.e., the polycystic kidney disease (PKD) model). microRNA can regulate microglial activation and vascular function, but the effect of microRNA-124 (miR-124) on retinal vasoregression remains unclear. Transgenic PKD and wild-type Sprague Dawley (SD) rats received miR-124 at 8 and 10 weeks of age intravitreally. Retinal glia activation was assessed by immunofluorescent staining and in situ hybridization. Vasoregression and neuroretinal function were evaluated by quantitative retinal morphometry and electroretinography (ERG), respectively. Microglial polarization was determined by immunocytochemistry and qRT-PCR. Microglial motility was examined via transwell migration assays, wound healing assays, and single-cell tracking. Our data showed that miR-124 inhibited glial activation and improved vasoregession, as evidenced by the reduced pericyte loss and decreased acellular capillary formation. In addition, miR-124 improved neuroretinal function. miR-124 shifted microglial polarization in the PKD retina from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype by suppressing TNF-α, IL-1β, CCL2, CCL3, MHC-II, and IFN-γ and upregulating Arg1 and IL-10. miR-124 also decreased microglial motility in the migration assays. The transcriptional factor of C/EBP-α-PU.1 signaling, suppressed by miR-124 both in vivo (PKD retina) and in vitro (microglial cells), could serve as a key regulator in microglial activation and polarization. Our data illustrate that miR-124 regulates microglial activation and polarization. miR-124 inhibits pericyte loss and thereby alleviates vasoregression and ameliorates neurovascular function.

miR-542-3p Attenuates Bone Loss and Marrow Adiposity Following Methotrexate Treatment by Targeting sFRP-1 and Smurf2

Intensive methotrexate (MTX) treatment for childhood malignancies decreases osteogenesis but increases adipogenesis from the bone marrow stromal cells (BMSCs), resulting in bone loss and bone marrow adiposity. However, the underlying mechanisms are unclear. While microRNAs (miRNAs) have emerged as bone homeostasis regulators and miR-542-3p was recently shown to regulate osteogenesis in a bone loss context, the role of miR-542-3p in regulating osteogenesis and adipogenesis balance is not clear. Herein, in a rat MTX treatment-induced bone loss model, miR-542-3p was found significantly downregulated during the period of bone loss and marrow adiposity. Following target prediction, network construction, and functional annotation/ enrichment analyses, luciferase assays confirmed sFRP-1 and Smurf2 as the direct targets of miR-542-3p. miRNA-542-3p overexpression suppressed sFRP-1 and Smurf2 expression post-transcriptionally. Using in vitro models, miR-542-3p treatment stimulated osteogenesis but attenuated adipogenesis following MTX treatment. Subsequent signalling analyses revealed that miR-542-3p influences Wnt/β-catenin and TGF-β signalling pathways in osteoblastic cells. Our findings suggest that MTX treatment-induced bone loss and marrow adiposity could be molecularly linked to miR-542-3p pathways. Our results also indicate that miR-542-3p might be a therapeutic target for preserving bone and attenuating marrow fat formation during/after MTX chemotherapy.

miR193a-5p Mediated ZNF746 and c-Myc Signaling Axis Is Critically Involved in Morusin Induced Apoptosis in Colorectal Cancer Cells

Novel target therapy is on the spotlight for effective cancer therapy. Hence, in the present study, the underlying apoptotic mechanism of Morusin was explored in association with miR193a-5p mediated ZNF746/c-Myc signaling axis in colorectal cancer cells (CRCs). Herein, Morusin reduced the viability and the number of colonies in HCT116 and SW480 CRCs. Additionally, Morusin increased sub-G1 population, cleavages of poly (ADP-ribose) polymerase (PARP) and caspase-3 and inhibited the expression of zinc finger protein 746 (ZNF746) and c-Myc in HCT116 and SW480 cells. Conversely, overexpression of ZNF746 suppressed the ability of Morusin to abrogate the expression of c-Myc in HCT116 cells, as ZNF746 enhanced the stability of c-Myc via their direct binding through nuclear colocalization in HCT116 cells by immunofluorescence and immunoprecipitation. Notably, Morusin upregulated miR193a-5p as a tumor suppressor, while miR193a-5p inhibitor masked the ability of Morusin to reduce the expression of ZNF746, c-Myc, and pro-PARP in HCT116 cells. To our knowledge, these findings provide the novel insight on miR193a-5p mediated inhibition of ZNF746/c-Myc signaling in Morusin induced apoptosis in CRCs.

Microglia-Derived Small Extracellular Vesicles Reduce Glioma Growth by Modifying Tumor Cell Metabolism and Enhancing Glutamate Clearance through miR-124

Brain homeostasis needs continuous exchange of intercellular information among neurons, glial cells, and immune cells, namely microglial cells. Extracellular vesicles (EVs) are active players of this process. All the cells of the body, including the brain, release at least two subtypes of EVs, the medium/large EVs (m/lEVs) and small EVs (sEVs). sEVs released by microglia play an important role in brain patrolling in physio-pathological processes. One of the most common and malignant forms of brain cancer is glioblastoma. Altered intercellular communications constitute a base for the onset and the development of the disease. In this work, we used microglia-derived sEVs to assay their effects in vitro on murine glioma cells and in vivo in a glioma model on C57BL6/N mice. Our findings indicated that sEVs carry messages to cancer cells that modify glioma cell metabolism, reducing lactate, nitric oxide (NO), and glutamate (Glu) release. sEVs affect Glu homeostasis, increasing the expression of Glu transporter Glt-1 on astrocytes. We demonstrated that these effects are mediated by miR-124 contained in microglia-released sEVs. The in vivo benefit of microglia-derived sEVs results in a significantly reduced tumor mass and an increased survival of glioma-bearing mice, depending on miR-124.

BNIP3-Dependent Mitophagy via PGC1α Promotes Cartilage Degradation

Since mitochondria are suggested to be important regulators in maintaining cartilage homeostasis, turnover of mitochondria through mitochondrial biogenesis and mitochondrial degradation may play an important role in the pathogenesis of osteoarthritis (OA). Here, we found that mitochondrial dysfunction is closely associated with OA pathogenesis and identified the peroxisome proliferator-activated receptor-gamma co-activator 1-alpha (PGC1α) as a potent regulator. The expression level of PGC1α was significantly decreased under OA conditions, and knockdown of PGC1α dramatically elevated the cartilage degradation by upregulating cartilage degrading enzymes and apoptotic cell death. Interestingly, the knockdown of PGC1α activated the parkin RBR E3 ubiquitin protein ligase (PRKN)-independent selective mitochondria autophagy (mitophagy) pathway through the upregulation of BCL2 and adenovirus E1B 19-kDa-interacting protein 3 (BNIP3). The overexpression of BNIP3 stimulated mitophagy and cartilage degradation by upregulating cartilage-degrading enzymes and chondrocyte death. We identified microRNA (miR)-126-5p as an upstream regulator for PGC1α and confirmed the direct binding between miR-126-5p and 3′ untranslated region (UTR) of PGC1α. An in vivo OA mouse model induced by the destabilization of medial meniscus (DMM) surgery, and the delivery of antago-miR-126 via intra-articular injection significantly decreased cartilage degradation. In sum, the loss of PGC1α in chondrocytes due to upregulation of miR-126-5p during OA pathogenesis resulted in the activation of PRKN-independent mitophagy through the upregulation of BNIP3 and stimulated cartilage degradation and apoptotic death of chondrocytes. Therefore, the regulation of PGC1α:BNIP3 mitophagy axis could be of therapeutic benefit to cartilage-degrading diseases.

Long noncoding RNA IL6-AS1 is highly expressed in chronic obstructive pulmonary disease and is associated with interleukin 6 by targeting miR-149-5p and early B-cell factor 1

Chronic obstructive pulmonary disease is a complex condition with multiple etiologies, including inflammation. We identified a novel long noncoding RNA (lncRNA), interleukin 6 antisense RNA 1 (IL6-AS1), which is upregulated in this disease and is associated with airway inflammation. We found that IL6-AS1 promotes the expression of inflammatory factors, especially interleukin (IL) 6. Mechanistically, cytoplasmic IL6-AS1 acts as an endogenous sponge by competitively binding to the microRNA miR-149-5p to stabilize IL-6 mRNA. Nuclear IL6-AS1 promotes IL-6 transcription by recruiting early B-cell factor 1 to the IL-6 promoter, which increases the methylation of the H3K4 histone and acetylation of the H3K27 histone. We propose a model of lncRNA expression in both the nucleus and cytoplasm that exerts similar effects through differing mechanisms, and IL6-AS1 probably increases inflammation via multiple pathways.

miR-19a-3p inhibition alleviates sepsis-induced lung injury via enhancing USP13 expression

Sepsis is a systemic inflammatory response syndrome caused by various pathogenic microorganisms or toxins. Lung damage is one of the causes of death in patients with sepsis. This study aimed to investigate the role of miR-19a-3p and its regulation mechanism in sepsis-induced lung injury. MH-S cells were treated with lipopolysaccharide (LPS) to establish sepsis-induced lung injury cell model. C57BL/6 mice were injected with miR-19a-3p antagomiR and LPS to construct animal model. LPS-treated and control cells were transfected with miR-19a-3p mimic, miR-19a-3p inhibitor or USP13 expression vector . The expression levels of miR-19a-3p and USP13 were examined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. The concentration of inflammatory cytokines was measured with enzyme-linked immunosorbent assay (ELISA). The relationship of miR-19a-3p and USP13 was validated using dual-luciferase reporter assay. The lung damage was assessed with hematoxylin-eosin staining (HE). The results showed that LPS treatment increased the concentration of TNF-α, IL-6 and IL-1β in MH-S cells. In LPS treated MH-S cells, the level of miR-19a-3p gradually increased over time. Both miR-19a-3p knockdown and USP13 overexpression in MH-S cells inhibited the LPS-induced production of TNF-α, IL-6 and IL-1β. Moreover, miR-19a-3p negatively regulated the expression of USP13 in MH-S cells. Furthermore, miR-19a-3p inhibitor suppressed lung damage in sepsis model mice. In conclusion, miR-19a-3p knockdown could alleviate sepsis-induced lung injury through enhancing USP13 expression.

MiR-222-3p downregulation prompted the migration, invasion and recruitment of endothelial progenitor cells via ADIPOR1 expression increase-induced AMKP activation

BACKGROUND

Clinical data show that aneurysm rupture causes high mortality in aged men. MicroRNAs (miRNAs) were reported to regulate endothelial progenitor cells (EPCs) which play a vital role in repairing endothelial damage and maintaining vascular integrity. This study identified a novel miRNA regulator for the functions of EPCs in aneurysm repair.

METHODS

Abdominal aortic aneurysm (AAA) model was established on Sprague-Dawley rats which later underwent antagomiR-222 treatment. The histopathological changes of AAA rats were examined by hematoxylin-eosin staining. Flow cytometry was performed to quantify EPCs in peripheral blood and identify EPCs isolated from the rat femur. The potential target of miR-222-3p was predicted by TargetScan v7.2 and validated by Dual-luciferase reporter assay. The effects of miR-222-3p and ADIPOR1 on the migration, invasion and tube formation of EPCs were evaluated by wound healing, Transwell and tube formation assays. The expressions of miR-222-3p and ADIPOR1 in aortic aneurysm tissues and EPCs were assessed by qRT-PCR or Western blot.

RESULTS

AAA exhibited histopathological abnormality, a decreased number of EPCs in the peripheral blood and an increased miR-222-3p expression. AntagomiR-222 injection reversed all these phenomena in AAA rats. Upregulating miR-222-3p expression inhibited the migration, invasion, and tube formation of EPCs, and the expressions of ADIPOR1 and phosphorylated-AMKP, while downregulating miR-222-3p expression exerted opposite effects in EPCs. ADIPOR1 was identified as a target gene of miR-222-3p. Overexpressing ADIPOR1 abrogated the effects of miR-222-3p upregulation on EPCs.

CONCLUSION

Downregulated miR-222-3p prompted the migration, invasion and recruitment of EPCs by targeting ADIPOR1-induced AMKP activation.

MicroRNA-30a-5p silencing polarizes macrophages toward M2 phenotype to alleviate cardiac injury following viral myocarditis by targeting SOCS1

Viral myocarditis (VMC) is a life-threatening disease characterized by severe cardiac inflammation generally caused by coxsackievirus B3 (CVB3) infection. Several microRNAs (miRNAs or miRs) are known to play crucial roles in the pathogenesis of VMC. The study aimed to decipher the role of miR-30a-5p in the underlying mechanisms of VMC pathogenesis. We first quantified miR-30a-5p expression in a CVB3-induced mouse VMC model. The physiological characteristics of mouse cardiac tissues were then detected by hematoxylin and eosin (HE) and Picrosirius red staining. We established the correlation between miR-30a-5p and SOCS1, using dual-luciferase gene assay and Pearson's correlation coefficient. The expression of inflammatory factors (IFN-γ, IL-6, IL-10, and IL-13), M1 polarization markers [TNF-α, inducible nitric oxide synthase (iNOS)], M2 polarization markers (Arg-1, IL-10), and myocardial hypertrophy markers [atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP)] was detected by RT-qPCR and Western blot analysis. miR-30a-5p was found to be highly expressed in VMC mice. Silencing of miR-30a-5p improved the cardiac function index and reduced heart weight-to-body weight ratio, myocardial tissue pathological changes and fibrosis degree, serological indexes, as well as proinflammatory factor levels, while enhancing anti-inflammatory factor levels in VMC mice. Furthermore, silencing of miR-30a-5p inhibited M1 polarization of macrophages while promoting M2 polarization in vivo and in vitro. SOCS1 was a target gene of miR-30a-5p, and the aforementioned cardioprotective effects of miR-30a-5p silencing were reversed upon silencing of SOCS1. Overall, this study shows that silencing of miR-30a-5p may promote M2 polarization of macrophages and improve cardiac injury following VMC via SOCS1 upregulation, constituting a potential therapeutic target for VMC treatment.NEW & NOTEWORTHY We found in this study that microRNA (miR)-30a-5p inhibition might improve cardiac injury following viral myocarditis (VMC) by accelerating M2 polarization of macrophages via SOCS1 upregulation. Furthermore, the anti-inflammatory mechanisms of miR-30a-5p inhibition may contribute to the development of new therapeutic strategies for VMC.

B7-H3, Negatively Regulated by miR-128, Promotes Colorectal Cancer Cell Proliferation and Migration

BACKGROUND

B7 homolog 3 (B7-H3), a member of the immunoregulatory ligand B7 family, is pivotal in T-cell-mediated immune response. It is widely expressed in diverse human tumors and its high expression indicates the poor prognosis of the patients. Nonetheless, B7-H3's role in colorectal cancer (CRC) needs to be further explored.

METHODS

Western blot and immunohistochemistry were employed for detecting B7-H3 protein expression in CRC tissues and cell lines, respectively. Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized for detecting B7-H3 mRNA and miR-128 expression levels. CRC cell lines SW620 and HT29 were used to construct B7-H3 overexpression or knockdown cell models, respectively. Cell counting kit-8 (CCK-8), 5-bromo-2'-deoxyuridine (BrdU), and scratch wound healing assays were employed for evaluating the effects of B7-H3 on CRC cell multiplication and migration. Besides, the regulatory relationship between miR-128 and B7-H3 was validated through dual-luciferase reporter gene assay, qRT-PCR, and western blotting.

RESULTS

B7-H3 expression level was remarkably elevated in CRC tissues and cell lines, and its high expression level was associated with increased tumor size, positive lymph node metastasis, and increased T stage. In CRC cells, B7-H3 overexpression significantly facilitated the cell multiplication and migration, while B7-H3 knockdown worked oppositely. Moreover, B7-H3 was identified as a target of miR-128, and miR-128 negatively regulated B7-H3 expression in CRC cells.

CONCLUSION

B7-H3 expression is upregulated in CRC tissues and cell lines, and B7-H3 participates in promoting the proliferation and migration of CRC cells. Besides, B7-H3 expression is negatively regulated by miR-128 in CRC.

MicroRNA-1278 ameliorates the inflammation of cardiomyocytes during myocardial ischemia by targeting both IL-22 and CXCL14

AIMS

This study aimed to elucidate the role of microRNAs (miRNAs) during myocardial infarction (MI) development in vivo and in vitro.

MAIN METHODS

Differentially expressed miRNAs between heart tissue from the MI mouse model and the control mouse were identified via microarray. Quantitative PCR (qPCR) and western blotting (WB) were performed to examine the expression levels of miRNAs and proteins, respectively. EdU-staining and colony formation assay were performed to assess cell viability and growth. Annexin V- and PI-staining-based flow cytometry was used to assess cell apoptosis. An MI mouse model was also established to study the function of miR-1278 in vivo.

KEY FINDINGS

The levels of miR-1278 were reduced in the infarct regions of heart tissues of the MI mouse model and in H2O2-treated newborn murine ventricular cardiomyocytes (NMVCs) compared to those in the heart tissues of healthy mice and non-treated NMVCs. H2O2 treatment suppressed the proliferation of NMVCs, while miR-1278 upregulation improved it. Moreover, we found that miR-1278 inhibited the upregulation of IL-22 and CXCL14 expression in H2O2-treated NMVCs by directly binding with the 3'-UTRs of both IL-22 and CXCL14. Furthermore, restoration of IL-22 and CXCL14 in H2O2-treated NMVCs promoted miR-1278-induced inflammation and apoptosis. Administration of agomiR-1278 to the MI mouse model significantly improved cardiac activity.

SIGNIFICANCE

Collectively, our findings illustrate that the expression of miR-1278 is low in H2O2-treated NMVCs and post-MI cardiac tissues, and the overexpression of miR-1278 in these protects against cell death by modulating IL-22 and CXCL14 expression.

The miR-199a/214 Cluster Controls Nephrogenesis and Vascularization in a Human Embryonic Stem Cell Model

MicroRNAs (miRNAs) are gene expression regulators and they have been implicated in acquired kidney diseases and in renal development, mostly through animal studies. We hypothesized that the miR-199a/214 cluster regulates human kidney development. We detected its expression in human embryonic kidneys by in situ hybridization. To mechanistically study the cluster, we used 2D and 3D human embryonic stem cell (hESC) models of kidney development. After confirming expression in each model, we inhibited the miRNAs using lentivirally transduced miRNA sponges. This reduced the WT1+ metanephric mesenchyme domain in 2D cultures. Sponges did not prevent the formation of 3D kidney-like organoids. These organoids, however, contained dysmorphic glomeruli, downregulated WT1, aberrant proximal tubules, and increased interstitial capillaries. Thus, the miR-199a/214 cluster fine-tunes differentiation of both metanephric mesenchymal-derived nephrons and kidney endothelia. While clinical implications require further study, it is noted that patients with heterozygous deletions encompassing this miRNA locus can have malformed kidneys.

MicroRNA-125a/VDR axis impaired autophagic flux and contributed to fibrosis in a CCL4-induced mouse model and patients with liver cirrhosis

AIMS

To clarify the role of the miR-125a/VDR axis in the regulation of autophagic flux in hepatocytes and liver fibrosis.

MAIN METHODS

The effects of the miR-125a/VDR axis on hepatic fibrosis and its underlying mechanisms were investigated in a carbon tetrachloride (CCl4)-induced mouse model and patients with liver cirrhosis by immunohistochemistry, real-time PCR, Western blotting, and luciferase reporter assay.

KEY FINDINGS

The degree of fibrosis in patients with liver cirrhosis was negatively correlated with VDR expression and autophagic flux in hepatocytes. Luciferase reporter assays confirmed that VDR is a direct target of miR-125a, which was positively correlated with the degree of fibrosis but negatively correlated with the autophagic flux and VDR expression in human liver cirrhosis tissue. miR-125a-antagomir-GFP AAV treatment partially restored VDR expression and autophagic flux and abrogated fibrosis in the liver of CCL4-induced mouse. In addition, knockdown of VDR abrogated the protective effect of miR-125a-antagomir-GFP AAV on autophagic flux and against liver fibrosis in the CCL4-induced mouse model.

SIGNIFICANCE

Our study for the first time identified the miR-125a/VDR axis as involved in the occurrence and development of liver fibrosis by regulating autophagic flux in hepatocytes.

miR-590-3p Alleviates diabetic peripheral neuropathic pain by targeting RAP1A and suppressing infiltration by the T cells

BACKGROUND

MicroRNAs play a crucial role in diabetic peripheral neuropathic pain (DPNP). miR-590-3p is a novel miRNA and involved in multiple diseases. However, the pathological mechanism of miR-590-3p in DPNP needs to be elucidated.

MATERIALS AND METHODS

The db/db mice and db/m mice were selected to mimic diabetes and control, respectively, for in vivo studies. The miR-590-3p agomir was injected into db/db mice and pain-related behavioral tests were performed. The interaction of miR-590-3p with target gene was confirmed by dual-luciferase reporter assay. The expression of target gene was determined by qRT-PCR and western blot assay. The levels of inflammatory cytokines were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

miR-590-3p was down-regulated in diabetic peripheral neuropathy mice. More importantly, miR-590-3p agomir alleviated pain-related behavior, reduced TNF-α, IL-1β and IL-6 concentrations, and inhibited neural infiltration by immune cells in db/db mice. Interestingly, RAP1A was predicted to be the target of miR-590-3p by Targetscan, and was actually regulated by miR-590-3p. Finally, the rescue experiments proved that overexpression of RAP1A partially abrogated the suppressive impact of miR-590-3p on T cells proliferation and migration.

CONCLUSION

miR-590-3p ameliorates DPNP via targeting RAP1A and inhibiting T cells infiltration, indicating that exogenous miR-590-3p may be a potential candidate for clinical treatment of DPNP.

MiR-149 attenuates the proliferation and migration of TGF-β1-induced airway smooth muscle cells by targeting TRPM7 and affecting downstream MAPK signal pathway

Asthma is considered as a general term for various chronic inflammatory diseases of the respiratory tract. Growing evidences have supported that microRNAs were involved in mediating cell proliferation, migration, and other cellular functions. MiR-149 has been found to take part in the development of various cancers. However, whether miR-149 participated in the proliferation and migration of transforming growth factor beta 1 (TGF-β1)-induced airway smooth muscle cells was still unknown. In this study, the expression level of miR-149 in human airway smooth muscle cells (ASMCs) was decreased after TGF-β1 treatment in vitro. Additionally, the over-expression of miR-149 obviously suppressed proliferation and migration in human ASMCs. Besides, we found that overexpression of miR-149 could inhibit the expression of transient receptor potential melastatin 7 (TRPM7) both in protein and gene levels. Furthermore, we demonstrated that miR-149 could inhibit the cell proliferation and migration in human ASMCs by targeting TRPM7 through modulating mitogen-activated protein kinases (MAPKs) signaling pathway. Taken together, we strongly supported that miR-149 might be a key inhibitor of asthma by targeting TRMP7. Therefore, our finding suggests a promising biomarker for the development of further targeted therapies for asthma.

MIR448 antagomir reduces arrhythmic risk after myocardial infarction by upregulating the cardiac sodium channel

Cardiac ischemia is associated with arrhythmias; however, effective therapies are currently limited. The cardiac voltage-gated sodium channel α subunit (SCN5A), encoding the Na_v1.5 current, plays a key role in the cardiac electrical conduction and arrhythmic risk. Here, we show that hypoxia reduces Na_v1.5 through effects on a miR, miR-448. miR-448 expression is increased in ischemic cardiomyopathy. miR-448 has a conserved binding site in 3′-UTR of SCN5A. miR-448 binding to this site suppressed SCN5A expression and sodium currents. Hypoxia-induced HIF-1α and NF-κB were major transcriptional regulators for MIR448. Moreover, hypoxia relieved MIR448 transcriptional suppression by RE1 silencing transcription factor. Therefore, miR-448 inhibition reduced arrhythmic risk after myocardial infarction. Here, we show that ischemia drove miR-448 expression, reduced Na_v1.5 current, and increased arrhythmic risk. Arrhythmic risk was improved by preventing Na_v1.5 downregulation, suggesting a new approach to antiarrhythmic therapy.

Ischemic induction of miR-448 negatively regulates the cardiac sodium channel Nav1.5, and inhibiting miR-448 raises Nav1.5 and reduces arrhythmic risk after myocardial infarction in mice.

Inhibiting microRNA-301b suppresses cell growth and targets RNF38 in cervical carcinoma

It has been reported microRNA-301b (miR-301b) was involved in the tumorigenesis of some cancers, but it has not been investigated in cervical carcinoma yet. In this study, miR-301b was found significantly upregulated in cervical carcinoma, and patients with high miR-301b expression had a shorter overall survival. When miR-301b was knocked down in cervical carcinoma cells, the cell growth could be significantly abolished. Our further studies showed miR-301b targeted RNF38, and inhibited its expression in cervical carcinoma cells. Moreover, RNF38 was found downregulated in cervical carcinoma, and miR-301b expression in cervical tissues was found negatively correlated with RNF38 expression. In addition, overexpression of RNF38 significantly inhibited cervical carcinoma cell growth, but overexpression of miR-301b suppressed RNF38-induced cell growth inhibition in cervical carcinoma. Collectively, this study suggested miR-301b could be a novel target for cervical carcinoma treatment.

Design of small molecules targeting RNA structure from sequence

The design and discovery of small molecule medicines has largely been focused on a small number of druggable protein families. A new paradigm is emerging, however, in which small molecules exert a biological effect by interacting with RNA, both to study human disease biology and provide lead therapeutic modalities. Due to this potential for expanding target pipelines and treating a larger number of human diseases, robust platforms for the rational design and optimization of small molecules interacting with RNAs (SMIRNAs) are in high demand. This review highlights three major pillars in this area. First, the transcriptome-wide identification and validation of structured RNA elements, or motifs, within disease-causing RNAs directly from sequence is presented. Second, we provide an overview of high-throughput screening approaches to identify SMIRNAs as well as discuss the lead identification strategy, Inforna, which decodes the three-dimensional (3D) conformation of RNA motifs with small molecule binding partners, directly from sequence. An emphasis is placed on target validation methods to study the causality between modulating the RNA motif in vitro and the phenotypic outcome in cells. Third, emergent modalities that convert occupancy-driven mode of action SMIRNAs into event-driven small molecule chemical probes, such as RNA cleavers and degraders, are presented. Finally, the future of the small molecule RNA therapeutics field is discussed, as well as hurdles to overcome to develop potent and selective RNA-centric chemical probes.

MicroRNA-302 represses epithelial-mesenchymal transition and cisplatin resistance by regulating ATAD2 in ovarian carcinoma

Epithelial-mesenchymal transition (EMT) is an important contributor to drug resistance in ovarian cancer. The aims of this study were to explore the potential role of the miR-302 cluster in modulating EMT and cisplatin resistance in ovarian cancer. We used qRT-PCR and western blotting to show that miR-302 expression was lower in chemoresistant than in chemosensitive cells, and miR-302 was upregulated in chemosensitive, but not chemoresistant ovarian cancer cells in response to cisplatin treatment. We identified ATAD2 as a target of miR-302 and showed that ectopic expression of miR-302 increased cisplatin sensitivity and inhibited EMT and the invasiveness of cisplatin-resistant cells in vitro by targeting ATAD2. Knockdown of ATAD2 restored cisplatin sensitivity and reversed EMT/metastasis in cisplatin-resistant cells, as shown by western blotting and invasion/migration assays. The effect of miR-302 overexpression on EMT and invasiveness was mediated by the modulation of β-catenin nuclear expression. Immunofluorescence analysis showed that ATAD2 overexpression reversed the miR-302-induced downregulation of nuclear β-catenin in cisplatin resistant cells. A xenograft tumor model was used to show that miR-302 increases the antitumor effect of cisplatin in vivo. Taken together, these results identify a potential regulatory axis involving miR-302 and ATAD2 with a role in chemoresistance, indicating that activation of miR-302 or inactivation of ATAD2 could serve as a novel approach to reverse cisplatin resistance in ovarian cancer.

miR-29a-3p suppresses hepatic fibrosis pathogenesis by modulating hepatic stellate cell proliferation via targeting PIK3R3 gene expression

OBJECTIVE

Hepatic stellate cells (HSC) activation and proliferation mediated the pathogenic development of hepatic fibrosis (HF). However, the underlying mechanisms remain poorly understood. In this study, we aimed to investigate the miR-29a-3p and its effects on PIK3R3 expression in HF pathogenesis.

METHODS

LX-2 cells treated with TGF-β1 was used as the in vitro HF model. The expression of microRNAs and proteins in LX-2 cells were detected by quantitative RT-PCR and western blotting. Then, miR-29a-3p expression in LX-2 cells were altered via transfection with specific mimics or inhibitors, followed by cell proliferation measured through CCK-8, Edu staining and colony formation. The dual luciferase reporter assay was done to assess binding of miR-29a-3p with PIK3R3 gene sequences. Moreover, PIK3R3 gene overexpression in LX-2 cell was realized through transfection with recombinant pcDNA3.0-PIK3R3 plasmids.

RESULTS

Successful establishment of cellular HF model was validated through the increased Col-I and a-SMA expression in TGF-β1-treated LX-2 cells shown by qRT-PCR and Western blot. In such model, miR-29a-3p expression in LX-2 cells showed the greatest decrease among four candidate microRNAs in response to TGF-β1 treatment. Also, miR-29a-3p directly binds with the 3' UTR region of the PIK3R3 gene to suppress its expression in LX-2 cells. Furthermore, PIK3R3 gene overexpression effectively abrogated the changes of LX-2 cell proliferation, AKT phosphorylation and Col-I and a-SMA expression caused by miR-29a-3p mimics.

CONCLUSION

MiR-29a-3p regulates hepatic stellate cell proliferation and hepatic fibrosis pathogenesis by targeting PIK3R3 expression and modulating the PI-3K/AKT signaling.

Effect of miR-124 on PI3K/Akt signal pathway in refractory epilepsy rats

This research aimed to investigate the effect of miR-124 on the PI3K/Akt signaling pathway in refractory epilepsy rats. Ten healthy SD rats were selected as a control group, thirty-six successfully established model rats were randomly divided into the model group, mir-124-agomir, mir-124-antagomir, mir-124-agomir+ LY294002 group (combined group), with 9 rats in each group. PI3K or (and) Akt expressions were intervened respectively. The changes in attack latency and cognitive function were observed, and the correlation among miR-124, PI3K, Akt, and attack latency was analyzed. Up-regulation of the level of miR-124 could increase the seizure interval of rats (P&lt; 0.05), improve the cognitive function of rats (P&lt; 0.05), and promote the expression of PI3K, AKT. The level of miR-124, PI3K, Akt was positively correlated with the latent time of seizures in rats, and the level of miR-124 was positively correlated with the level of PI3K, Akt (P&lt; 0.05). In conclusion, miR-124 can play a protective role in temporal lobe epilepsy by promoting PI3K/Akt signaling pathway, including the protection of cognitive function, which may be a potential target for clinical treatment of intractable epilepsy in the future.

miR-20b and miR-451a Are Involved in Gastric Carcinogenesis through the PI3K/AKT/mTOR Signaling Pathway: Data from Gastric Cancer Patients, Cell Lines and Ins-Gas Mouse Model

Gastric cancer (GC) is one of the most common and lethal gastrointestinal malignancies worldwide. Many studies have shown that development of GC and other malignancies is mainly driven by alterations of cellular signaling pathways. MicroRNAs (miRNAs) are small noncoding molecules that function as tumor-suppressors or oncogenes, playing an essential role in a variety of fundamental biological processes. In order to understand the functional relevance of miRNA dysregulation, studies analyzing their target genes are of major importance. Here, we chose to analyze two miRNAs, miR-20b and miR-451a, shown to be deregulated in many different malignancies, including GC. Deregulated expression of miR-20b and miR-451a was determined in GC cell lines and the INS-GAS mouse model. Using Western Blot and luciferase reporter assay we determined that miR-20b directly regulates expression of PTEN and TXNIP, and miR-451a: CAV1 and TSC1. Loss-of-function experiments revealed that down-regulation of miR-20b and up-regulation of miR-451a expression exhibits an anti-tumor effect in vitro (miR-20b: reduced viability, colony formation, increased apoptosis rate, and miR-451a: reduced colony forming ability). To summarize, the present study identified that expression of miR-20b and miR-451a are deregulated in vitro and in vivo and have a tumor suppressive role in GC through regulation of the PI3K/AKT/mTOR signaling pathway.

MiR-140-3p inhibits natural killer cytotoxicity to human ovarian cancer via targeting MAPK1

Natural killer (NK) cells have pivotal role in immunotherapy of human ovarian cancer (OC). Although microRNAs (miRNAs) participate in dysfunction of NK cells, how and whether miR-140-3p regulates cytotoxicity of NK cells in OC are uncertain. miR-140-3p and mitogen activated protein kinase 1 (MAPK1) abundances were examined via quantitative real-time polymerase chain reaction or western blot. Tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) abundances were examined via enzyme linked immunosorbent assay. NK cytotoxicity to OC was evaluated via lactate dehydrogenase release. The relevance of miR-140-3p and MAPK1 was proved via luciferase activity analysis. Murine xenograft experiment was applied to assess the function of miR-140-3p on NK cytotoxicity. miR-140-3p was elevated and MAPK1 was declined in NK cells from OC patients, while the levels were reversed after treatment of interleukin-2 (IL-2). MiR-140-3p addition mitigated IFN-γ and TNF-α production induced via IL-2 as well as NK-92 cytotoxicity to OC cells. Additionally, MAPK1 was negatively regulated via miR-140-3p and ablated the influence of miR140-3p on cytotoxicity, cytokines levels. Besides, miR-140-3p enrichment facilitated tumor growth via suppressing function of NK cells in a xenograft model. miR-140-3p suppressed NK cytotoxicity to OC cells via mediating MAPK1, indicating a new avenue of ameliorating NK cells function for OC treatment.

MiR-222 inhibition alleviates Staphylococcal Enterotoxin B-induced inflammatory acute lung injury by targeting Foxo3

Acute lung injury (ALI) is a common acute and severe disease in clinical practice. Staphylococcal Enterotoxin B (SEB) is a superantigen that can cause inflammatory ALI. MiR-222 has been demonstrated to be upregulated in SEB-induced inflammatory ALI, but its exact roles and functions remain ill-defined. In this study, SEB exposure led to inflammatory ALI and high expression of miR-222 in model mice and lung infiltrating mononuclear cells, but the inflammatory response and high expression of miR-222 were restored in miR-222^-/- mice. Moreover, we investigated the roles of miR-222 in vitro and observed that the concentrations of inflammatory cytokines and the expression of miR-222 were all elevated in SEB-activated splenocytes and miR-222 inhibition reversed the effects. Foxo3 was confirmed as a direct target of miR-222. Interestingly, SEB exposure led to a decrease of Foxo3 expression, and Foxo3 knockdown partially reversed the promotion of Foxo3 and the inhibition of inflammatory cytokines induced by miR-222 inhibitor in SEB-activated splenocytes. Our data indicated that miR-222 inhibition could alleviate SEB-induced inflammatory ALI by directly targeting Foxo3, shedding light on the potential therapeutic of miR-222 for SEB-induced inflammation in the lung.

LncRNA KLF3-AS1 in human mesenchymal stem cell-derived exosomes ameliorates pyroptosis of cardiomyocytes and myocardial infarction through miR-138-5p/Sirt1 axis

AIM

Myocardial infarction (MI) is a severe disease with increased mortality and disability rates, posing heavy economic burden for society. Exosomes were uncovered to mediate intercellular communication after MI. This study aims to explore the effect and mechanism of lncRNA KLF3-AS1 in exosomes secreted by human mesenchymal stem cells (hMSCs) on pyroptosis of cardiomyocytes and MI.

METHODS

Exosomes from hMSCs were isolated and identified. Exosomes from hMSCs with transfection of KLF3-AS1 for overexpression were injected into MI rat model or incubated with hypoxia cardiomyocytes. Effect of KLF3-AS1 on MI area, cell viability, apoptosis, and pyroptosis was determined. The relationship among miR-138-5p, KLF3-AS1, and Sirt1 was verified by dual-luciferase reporter assay. Normal cardiomyocytes were transfected with miR-138-5p inhibitor or sh-Sirt1 to clarify whether alteration of miR-138-5p or sh-Sirt1 can regulate the effect of KLF3-AS1 on cardiomyocytes.

RESULTS

Exosomes from hMSCs were successfully extracted. Transfection of KLF3-AS1 exosome in rats and incubation with KLF3-AS1 exosome in hypoxia cardiomyocytes both verified that overexpression of KLF3-AS1 in exosomes leads to reduced MI area, decreased cell apoptosis and pyroptosis, and attenuated MI progression. KLF3-AS1 can sponge miR-138-5p to regulate Sirt1 expression. miR-138-5p inhibitor transfection and KLF3-AS1 exosome incubation contribute to attenuated pyroptosis and MI both in vivo and in vitro, while transfection of sh-Sirt1 could reverse the protective effect of exosomal KLF3-AS1 on hypoxia cardiomyocytes.

CONCLUSION

LncRNA KLF3-AS1 in exosomes secreted from hMSCs by acting as a ceRNA to sponge miR-138-5p can regulate Sirt1 so as to inhibit cell pyroptosis and attenuate MI progression.

Systems biology-based investigation of cooperating microRNAs as monotherapy or adjuvant therapy in cancer

MicroRNAs (miRNAs) are short, noncoding RNAs that regulate gene expression by suppressing mRNA translation and reducing mRNA stability. A miRNA can potentially bind many mRNAs, thereby affecting the expression of oncogenes and tumor suppressor genes as well as the activity of whole pathways. The promise of miRNA therapeutics in cancer is to harness this evolutionarily conserved mechanism for the coordinated regulation of gene expression, and thus restoring a normal cell phenotype. However, the promiscuous binding of miRNAs can provoke unwanted off-target effects, which are usually caused by high-dose single-miRNA treatments. Thus, it is desirable to develop miRNA therapeutics with increased specificity and efficacy. To achieve that, we propose the concept of miRNA cooperativity in order to exert synergistic repression on target genes, thus lowering the required total amount of miRNAs. We first review miRNA therapies in clinical application. Next, we summarize the knowledge on the molecular mechanism and biological function of miRNA cooperativity and discuss its application in cancer therapies. We then propose and discuss a systems biology approach to investigate miRNA cooperativity for the clinical setting. Altogether, we point out the potential of miRNA cooperativity to reduce off-target effects and to complement conventional, targeted, or immune-based therapies for cancer.