miR-155 Inhibitor Research Articles

Exosomal Delivery of miR-155 Inhibitor can Suppress Migration, Invasion, and Angiogenesis Via PTEN and DUSP14 in Triple-negative Breast Cancer.

Triple-Negative Breast Cancer (TNBC) is the most common type of breast cancer (BC). In order to develop effective treatments for TNBC, it is vital to identify potential therapeutic targets. Angiogenesis stimulates tumor growth and metastasis in TNBC, and miR-155 plays a crucial role in this process. The exosome is a nano-sized vesicle that carries many cargoes, including miRNAs. The present study investigated the effect of exosomal delivery of miR-155 antagomir on tumor migration, invasion, and angiogenesis in TNBC. From MDA-MB-231 cells, exosomes were extracted, characterized, and loaded with miR-155 antagomir using electroporation. The expression of miR-155 and its target genes, including PTEN and DUSP14, was analyzed using RTqPCR. The wound-healing and transwell assays were used to measure cell migration and invasion. Furthermore, angiogenesis was evaluated by tube formation and chorioallantoic membrane (CAM) assays. The results indicated that exosomal delivery of miR-155 antagomir to HUVEC cells significantly suppressed miR-155 expression while upregulating PTEN and DUSP14. The tube formation properties of HUVEC cells were also significantly reduced following treatment with exosomes containing miR-155 antagomirs, and these results were confirmed using CAM assay. The migration and invasion of MDA-MB-231 cells were significantly reduced after treatment with miR-155 antagomir-loaded exosomes. It was found that miR-155 antagomir delivery using exosomes can inhibit migration, invasion, and angiogenesis viaPTEN and DUSP14 in TNBC.

Clinical implications of miRNAs in erythropoiesis, anemia, and other hematological disorders.

Erythropoiesis is regulated by the differential expression of many genes. Besides being transcriptionally regulated, these genes are also with the oath of epigenetic regulation by the microRNAs (miRNAs), in particular. Various miRNAs appear to be very important for the normal process of erythropoiesis and various hematological abnormalities in humans. Therefore, the review aims to summarize the significance of miRNAs in erythropoiesis and different hematological diseases with clinical importance. Our analysis indicates that specific miRNAs regulate erythropoiesis in a stage-specific manner from hematopoietic stem cells to differentiated erythrocytes. Further, many miRNAs have been reported to be linked with various hematological diseases. The importance of miRNAs as biomarkers or therapeutic drug targets for various hematological disorders like anemia, β-thalassemia, and leukemia has been revealed through various clinical studies and clinical trials. The miR-34a mimic and miR-155 inhibitor demonstrate promising therapeutic effects in various hematological malignancies. Additionally, miR-34a, miR-538e, miR-193e, and miR-198 exhibit diagnostic potential in acute myeloid leukemia, while miR-451, miR-151-5p, and miR-1290 show diagnostic potential in B-cell acute lymphoblastic leukemia. Thus, this review encompasses the latest observations and implications of specific miRNAs in erythropoiesis and various hematological disorders. However, challenges persist in developing safe and efficient delivery strategies to target miRNAs specifically, minimizing off-target effects and enhancing therapeutic outcomes. Future mechanistic pre-clinical and clinical research would contribute to overcoming these challenges.

Inflammatory factor-mediated miR-155/SOCS1 signaling axis leads to Treg impairment in systemic lupus erythematosus

BackgroundSystemic lupus erythematosus (SLE) is an autoimmune disorder associated with the decrease and functional impairment of regulatory T cells (Tregs). In the current study, we explored the interplay of miR-155 and suppressor of cytokine signaling 1 (SOCS1) in regulating Treg function and stability in SLE. MethodsClinical samples from healthy subjects and SLE patients were collected, and a mouse model of SLE was established to profile the expression pattern of miR-155 and SCOS1 in Tregs. Tregs isolated from mouse spleen were stimulated by inflammatory cytokines to confirm involvement of miR-155/SOCS1 axis in dictating Treg stability and function. We also administrated synthetic miR-155 inhibitor in SLE animal model to evaluate the potential effect on rescuing Treg function and alleviating SLE progression. ResultsTregs from SLE patients and SLE-induced mice exhibited a downregulation of SOCS1 and an upregulation of miR-155. In Tregs stimulated by inflammatory cytokines, Nuclear factor kappa B (NF-κB) signaling activation was required for the change of SOCS1 and miR-155 expression. miR-155 served as a negative regulator to dampen SOCS1 expression in inflammation-stimulated Tregs. The transfection of miR-155 mimic impaired the suppressive function and differentiation of Tregs through targeting SOCS1. In contrast, miR-155 inhibition improved Treg function under inflammatory stimulation and alleviated SLE conditions in the mouse model. ConclusionInflammation-induced miR-155 impairs Treg stability and function in SLE through decreasing SOCS1 expression. Targeting miR-155 might be developed as an intervention to mitigate SLE conditions.

MiR-221 on protective oxidative induced by selenium modified Codonopsis pilosula polysaccharide

Oxidative stress plays an important role in various diseases. miR-221 has been reported to regulate oxidative stress. However, the mechanism of miR-221 in regulating oxidative stress induced by sCPPS5 remains unclear. This study aimed to investigate the protective effects and mechanisms of miR-221 on oxidative stress induced by sCPPS5. The expression of SOD, CAT, MDA, LDH, MMP, caspase-3 activity and apoptosis were measured. In addition, the key signaling factors in the Keap1-Nrf2-ARE signaling pathway were determined by real-time PCR and Western blot. Mice were employed to evaluate the effects of sCPPS5 and the possible mechanism in vivo. sCPPS5 promoted the expression of SOD and CAT and activated Keap1-Nrf2-ARE signaling pathway inhibit the MDA content, MMP, caspase-3 activity, apoptosis and LDH release rate after transfection with miR-221 mimics and inhibitors. Consistently, sCPPS5 has the potential to enhance the expression of antioxidant enzymes as well as upregulate mRNA expression of crucial signal proteins in vivo. miR-221 on oxidative stress protection induced by sCPPS5 possibly through regulating the Keap1-Nrf2-ARE signaling pathway in macrophages.

Abstract We129: Endothelium-Targeted MiR-122 Inhibition Improves Vascular Endothelial Function In a High-Fat Diet Fed mice

Background: MicroRNA-122-5p (miR-122), a liver-specific miR, levels are increased in the blood during obesity and diabetes and is taken-up by the extra-hepatic tissues including vascular endothelium. Despite miR-122’s role in maintaining hepatic homeostasis, its uptake (from circulation) by other tissues disrupts their function and increases the risk of cardiovascular disorders. Hence, inhibiting extra-hepatic miR-122 is a viable approach to mitigate vascular disorders associated with diabetes. Hypothesis: Endothelium-targeted miR-122 inhibitor selectively targets miR-122 in endothelial cells and improves vascular endothelial function in high-fat-diet (HFD) fed pre-diabetic mice. Methods: To selectively inhibit miR-122 in the endothelial cells, we synthesized gamma-peptide nucleic acid miR-122 inhibitor (γP-122 I) tagged with vascular cell adhesion molecule 1 (VCAM1) targeted peptide (e-γP-122 I). The purity was assessed using HPLC. Pre-diabetic condition was induced by feeding mice with a HFD (for 8 weeks) and e-γP-122-I was injected to the HFD-fed mice (2 weeks after dietary intervention; 5 mg/kg/day, i.p., 6 weeks). MiR-122 expression was measured by real-time PCR. The vascular endothelial function was assessed by determining endothelium-dependent and independent relaxation of phenylephrine-induced precontracted aortic rings. Results were expressed as mean ± s.e.m. Results: The e-γP-122-I was >95% pure. The HFD-fed mice show higher levels of serum and aortic miR-122 expression and impaired vascular endothelial function. e-γP-122-I treatment selectively inhibited aortic miR-122 expression while it has no effect on other organs (heart, kidney etc.) and improved vascular endothelial function and inflammation. Conclusions: e-γP-122-I selectively inhibits miR-122 in the endothelium and improves endothelial function in pre-diabetic mice.

Macrophage-derived exosomal miR-155 regulating hepatocyte pyroptosis in MAFLD

BackgroundPrevious studies have shown that pyroptosis in hepatocyte is essential for the development of MAFLD. Growing evidence has shown that exosomal miRNAs-mediated communication between inflammatory cells and hepatocyte is an important link in MAFLD. In the present study, we aim to elucidate whether macrophage-derived exosomal miRNAs contribute to the hepatocyte pyroptosis in the pathophysiological process of MAFLD. MethodsThe effects of hepatocyte pyroptosis were investigated in an HFD-induced MAFLD mouse model and in the liver tissues from patients with MAFLD using immunohistochemistry, real-time PCR, Western blotting, and luciferase reporter assay, among other techniques. MiR-155 inhibitor tail injections and AAV-FoxO3a-GFP were also administered to respectively inhibit or overexpress its expression in an HFD-induced MAFLD mouse model. ResultsHepatocyte pyroptosis was heightened in the liver tissue of patients with MAFLD or HFD-induced MAFLD mouse. Importantly, treatment with a caspase-1 inhibitor or overexpression of FoxO3a reversed this trend. Our study also demonstrated that miR-155 expression and the number of infiltrated macrophages were increased, and knockdown of miR-155 attenuated hepotocyte pyroptosis and liver fibrosis in HFD-induced mouse. In addition, we demonstrated that macrophage-derived exosomal miR-155 was transferred to hepatocytes, leading to hepatocyte pyroptosis in MAFLD mouse. Furthermore, blockade of exosome secretion improved hepotocyte pyroptosis and liver fibrosis in HFD-induced mouse. On the contrary, macrophage-derived exosomal miR-155 worsened hepotocyte pyroptosis. Moreover, we found that miR-155 promoted hepatocyte pyroptosis in MAFLD by down-regulating FoxO3a. ConclusionsTaken together, our results demonstrated that macrophage-derived exosomal miR-155 promotes hepatocyte pyroptosis and liver fibrosis in MAFLD.

A tetrahedral DNA nanostructure-mediated miRNA inhibitor delivery system: Type H vessel-related bone healing during distraction osteogenesis

The clinical treatment of critical bone defects presents a great challenge, and distraction osteogenesis (DO) emerges as a highly effective strategy. However, prolonged consolidation periods resultant complications limit its clinical applicability. MicroRNA (miR) therapeutic strategies, with a notable focus on miR-205, demonstrate significant potential during DO. Nevertheless, the limited cellular uptake and facile biodegradation of miRNA constrain its applications. To address these challenges, we introduce tetrahedral DNA nanostructure (TDN), an innovative nanomaterial, engineered as gene carriers. TDN delivers the miR-205 inhibitor (TDN@miR205) to synthesize the novel nanoparticles that support bone healing for the first time. TDN@miR205 enhances the osteogenic potential of bone marrow-derived mesenchymal stem cells (BMSCs), whereas TDN alone is ineffective. Further exploration reveals TDN-modulated angiogenesis-osteogenesis communication, establishing a crucial intercellular regulatory mechanism. Notably, TDN@miR205 expedites bone formation by promoting type H vessels-related angiogenesis, secreting SLIT3 to inhibit osteoclasts, inducing SDF1 homing of BMSCs, then upregulating osteogenic genes and proteins via the TGF-β/BMP pathway, facilitating early bony ossification both in vitro and in vivo. In conclusion, TDN@miR205, the multifunctional nanoparticle-mediated vascular bone regeneration significantly contributes to ossification in DO and establishes this platform as a promising and versatile strategy for addressing DO and other complex bone diseases.

RNA Technology to Regenerate and Repair Alveolar Bone Defects

microRNA-200a (miR-200a) targets multiple signaling pathways that are involved in osteogenic differentiation and bone development. However, its therapeutic function in osteogenesis and bone regeneration remains unknown. In this study, we use in vitro and in vivo models to investigate the molecular function of miR-200a overexpression and miR-200a inhibition using a plasmid-based miR inhibitor system (PMIS) on osteogenic differentiation and bone regeneration. Inhibition of miR-200a using PMIS-miR-200a significantly increased osteogenic biomarkers of human embryonic palatal mesenchyme cells and promoted bone regeneration in rat tooth socket defects. In rat maxillary M1 molar extractions, the supporting tooth structures were removed with an implant drill to yield a 3-mm defect in the alveolar bone. A collagen sponge was inserted into the open alveolar defect and PMIS-miR-200a plasmid DNA was added to the sponge and the wound sutured to protect the sponge and close the defect. It was important to remove the existing tooth supporting structure, which can influence alveolar bone regeneration. The alveolar bone was regenerated in 4 wk. The collagen sponge acts to stabilize and deliver the PMIS-miR-200a DNA to cells entering the sponge in the bone defect. We show that mesenchymal stem cells expressing CD90 and Stro-1 enter the sponges, take up the DNA, and express PMIS-miR-200a. PMIS-miR-200a initiates a bone regeneration program in transformed cells in vivo. In vitro inhibition of miR-200a was found to upregulate Wnt and BMP signaling activity as well as Runx2, OCN, Lef-1, Msx2, and Dlx5 associated with osteogenesis. Liver and blood toxicity testing of PMIS-miR-200a–treated rats showed no increase in several biomarkers of liver disease. These results demonstrate the therapeutic function of PMIS-miR-200a for rapid bone regeneration. Furthermore, the studies were designed to demonstrate the ease of use of PMIS-miR-200a in solution and applied using a syringe in the clinic through a simple one-time application.

Use of Therapeutic RNAs to Accelerate Wound Healing in Diabetic Rabbit Wounds.

Introduction: Diabetes mellitus (DM) affects over 422 million people globally. Patients with DM are subject to a myriad of complications, of which diabetic foot ulcers (DFUs) are the most common with ∼25% chance of developing these wounds throughout their lifetime. Innovation: Currently there are no therapeutic RNAs approved for use in DFUs. Use of dressings containing novel layer-by-layer (LbL)-formulated therapeutic RNAs that inhibit PHD2 and miR-210 can significantly improve diabetic wound healing. These dressings provide sustained release of therapeutic RNAs to the wounds locally without systemic side effects. Clinical Problem Addressed: Diabetic foot wounds are difficult to heal and often result in significant patient morbidity and mortality. Materials and Methods: We used the diabetic neuroischemic rabbit model of impaired wound healing. Diabetes was induced in the rabbits with alloxan, and neuroischemia was induced by ligating the central neurovascular bundle of each ear. Four 6-mm full-thickness wounds were created on each ear. A LbL technique was used to conformally coat the wound dressings with chemically modified RNAs, including an antisense oligonucleotide (antimiR) targeting microRNA-210 (miR-210), an short synthetic hairpin RNA (sshRNA) targeting PHD2, or both. Results: Wound healing was improved by the antimiR-210 but not the PHD2-sshRNA. Specific knockdown of miR-210 in tissue as measured by RT-qPCR was ∼8 Ct greater than nonspecific controls, and this apparent level of knockdown (>99%) suggests that delivery to the tissue is highly efficient at the administered dose. Discussion: Healing of ischemic/neuropathic wounds in diabetic rabbits was accelerated upon inhibition of miR-210 by LbL delivery to the wound bed. miR-210 inhibition was achieved using a chemically modified antisense RNA.

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

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

MiR-122/PPARβ axis is involved in hypoxic exercise and modulates fatty acid metabolism in skeletal muscle of obese rats

Hypoxic exercise is an effective intervention for obesity, because it promotes weight loss by regulating fatty acid (FA) metabolism. The regulation of peroxisome proliferator-activated receptor β (PPARβ) by miR-122 may be involved in this process, but the detailed mechanisms are unknown. In order to address this issue, we probed how miR-122 affected the expression of factors associated with FA metabolism in skeletal muscle of obese rats undergoing hypoxic training. By injecting adeno-associated virus 9 containing miR-122 overexpression vector or miR-122 inhibitor into skeletal muscles of rats with a 4-week hypoxic exercise regimen, the miR-122 expression level can be regulated. Body composition and blood lipid levels were analyzed, and PPARβ, carnitine palmitoyltransferase 1b (CPT1b), acetylCoA carboxylase 2 (ACC2), and FA synthase (FAS) mRNA and protein levels were evaluated using quantitative reverse transcription quantitative PCR(RT-qPCR) and Western blot analysis. We found that miR-122 overexpression increased low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) levels and decreased PPARβ, ACC2, and FAS expression. Conversely, miR-122 inhibition decreased TG level, increased high-density lipoprotein cholesterol (HDL-C) level, and upregulated PPARβ, ACC2, FAS, and CPT1b. These data indicated that the negative regulation of PPARβ by miR-122 promotes FA metabolism by altering the levels of the factors related to FA metabolism in skeletal muscle of obese rat under hypoxic training, thus providing molecular-level insight into the beneficial effects of this intervention.

MicroRNA-194 regulates parasitic load and IL-1β-dependent nitric oxide production in the peripheral blood mononuclear cells of dogs with leishmaniasis.

Domestic dogs are the primary urban reservoirs of Leishmania infantum, the causative agent of visceral leishmaniasis. In Canine Leishmaniasis (CanL), modulation of the host's immune response may be associated with the expression of small non-coding RNAs called microRNA (miR). miR-194 expression increases in peripheral blood mononuclear cells (PBMCs) of dogs with leishmaniasis with a positive correlation with the parasite load and in silico analysis demonstrated that the TRAF6 gene is the target of miR-194 in PBMCs from diseased dogs. Here, we isolated PBMCs from 5 healthy dogs and 28 dogs with leishmaniasis, naturally infected with L. infantum. To confirm changes in miR-194 and TRAF6 expression, basal expression of miR-194 and gene expression of TRAF6 was measured using qPCR. PBMCs from healthy dogs and dogs with leishmaniasis were transfected with miR-194 scramble, mimic, and inhibitor and cultured at 37° C, 5% CO2 for 48 hours. The expression of possible targets was measured: iNOS, NO, T-bet, GATA3, and FoxP3 were measured using flow cytometry; the production of cytokines IL-1β, IL-4, IL-6, IL-10, TNF-α, IFN-γ, and TGF-β in cell culture supernatants was measured using capture enzyme-linked immunosorbent assays (ELISA). Parasite load was measured using cytometry and qPCR. Functional assays followed by miR-194 inhibitor and IL-1β blockade and assessment of NO production were also performed. Basal miR-194 expression was increased in PBMC from dogs with Leishmaniasis and was negatively correlated with TRAF6 expression. The mimic of miR-194 promoted an increase in parasite load. There were no significant changes in T-bet, GATA3, or FoxP3 expression with miR-194 enhancement or inhibition. Inhibition of miR-194 increased IL-1β and NO in PBMCs from diseased dogs, and blockade of IL-1β following miR-194 inhibition decreased NO levels. These findings suggest that miR-194 is upregulated in PBMCs from dogs with leishmaniasis and increases parasite load, possibly decreasing NO production via IL-1β. These results increase our understanding of the mechanisms of evasion of the immune response by the parasite and the identification of possible therapeutic targets.

Apolipoprotein A-I inhibited group II innate lymphoid cell response mediated by microRNA-155 in allergic rhinitis

BackgroundGroup 2 innate lymphoid cells (ILC2s) have been found to take part in type 2 inflammation by secreting Th2 cytokines. Apolipoprotein A-I (Apo-AI), a major structural and functional protein of high-density lipoproteins, plays anti-inflammatory effects on neutrophils, monocytes, macrophages and eosinophils. However, its effects on ILC2 are not well characterized. ObjectiveIn this study, we aimed to investigate to the effect of Apo-AI on the proliferation and function of ILC2 as well as possible mechanism. MethodsThe protein expression of Apo-AI and the percentage of ILC2 in peripheral blood between 20 AR and 20 controls were detected using enzyme-linked immunosorbnent assay (ELISA) and flow cytometry. The effect of Apo-AI and miR-155 on ILC2 proliferation and function were detected by tritiated thymidine incorporation and ELISA. Anima models were adopted to verify the effect of Apo-AI in vivo. ResultsElevated expression of Apo-AI was observed in AR patients. The Apo-AI promotes ABCA1 expression by ILC2, which can be inhibited by anti-Apo-AI. The Apo-AI decreased ILC2 proliferation and the mRNA levels of GATA3 and RORα from ILC2. The miR-155 over-expression promoted the up-regulation of GATA-3 and type II cytokines from ILC2, while the addition of Apo-AI or miR-155 inhibitor inhibited the expression of GATA-3 and type II cytokines by ILC2 significantly. Apo-AI-/- mice showed as enhanced allergen-induced airway inflammation. The miR-155 inhibitor can reverse the enhanced allergen-induced airway inflammation in Apo-AI-/- mice, while miR-155 mimics can reverse the decreased allergen-induced airway inflammation in Apo-AI treated mice. ConclusionApo-AI suppressed the proliferation and function of ILC2 through miR-155 in AR. Our data provided new insights into the mechanism of allergen-induced airway inflammation.

Novel Circular RNA CircUBAP2 Drives Tumor Progression by Regulating the miR-143/TFAP2B Axis in Prostate Cancer.

More and more investigations reveal that circular RNAs (circRNAs) are involved in cancer progression. CircRNA UBAP2 was closely related to prostate cancer. However, the biological function and specifical mechanism of circUBAP2 are still poorly discovered in prostate cancer (PCa). This study aims to explore the biological function and mechanism of circUBAP2 in PCa. The levels of mRNA and proteins were assessed by qRT-PCR assay and Western blot, respectively. Cell growth, migration, and invasion ability were measured using CCK-8 assay and Transwell assay. Apoptosis was assessed using flow cytometry. The interactions between circUBAP2, miR-143, and TFAP2B were determined by luciferase report assay. The tumor growth was determined by in vivo tumor formation assay. The tumor morphology was assessed using H&E staining assay, and immunohistochemistry assay was conducted to assess the level of KI67. We found circUBAP2 and TFAP2B were notably elevated, while miR-143 was largely attenuated in prostate cancer cells and tissues. CircUBAP2 was found to affect cell viability, metastasis and EMT, while attenuating the apoptosis rate of prostate cancer cells. CircUBAP2 directly targeted miR-143, and miR-143 inhibitor could reverse the effects that circUBAP2 interference-induced in prostate cancer cells. TFAP2B is directly bound to miR-143, and overexpression of TFAP2B could attenuate the influences that miR-143-induced in prostate cancer cells. CircUBAP2 promoted prostate cancer progression via miR-143/TFAP2B axis.

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

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

Antiviral therapy reduces hepatocellular carcinoma through suppressing hepatitis B virus replication may improve ER stress, mitochondrial and metabolic dysfunctions and decrease p62 in hybridized mice with single HBV transgene and miR-122.

Hepatitis B virus (HBV) hijacks autophagy for its replication. Nucleos(t)ide analogs (NUCs) treatment suppressed HBV replication and reduced hepatocellular carcinoma (HCC) incidence. However, the use of NUCs in chronic hepatitis B (CHB) patients with normal or minimally elevated serum alanine aminotransferase (ALT) levels is still debated. Animal models are crucial for studying the unanswered issue and evaluating new therapies. MicroRNA-122 (miR-122), which regulates fatty acid and cholesterol metabolism, is downregulated during hepatitis and HCC progression. The reciprocal inhibition of miR-122 with HBV highlights its role in HCC development as a tumor suppressor. By crossbreeding HBV-transgenic mice with miR-122 knockout mice, we generated a hybrid mouse model with a high incidence of HCC up to 89% and normal ALT levels before HCC. The model exhibited early-onset hepatic steatosis, progressive liver fibrosis, and impaired late-phase autophagy. Metabolomics and microarray analysis identified metabolic signatures, including dysregulation of lipid metabolism, inflammation, genomic instability, the Warburg effect, reduced TCA cycle flux, energy deficiency, and impaired free radical scavenging. Antiviral treatment reduced HCC incidence in hybrid mice by approximately 30-35% compared to untreated mice. This effect was linked to the activation of ER stress-responsive transcription factor ATF4, clearance of autophagosome cargo p62, and suppression of the CHOP-mediated apoptosis pathway. In summary, this study suggests that despite minimal ALT elevation, HBV replication can lead to liver injury. Endoplasmic reticulum stress, reduced miR-122 levels, mitochondrial and metabolic dysfunctions, blocking protective autophagy resulting in p62 accumulation, apoptosis, fibrosis, and HCC. Antiviral may improve the above-mentioned pathogenesis through HBV suppression.

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

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

Chitosan nanoparticles-based in vivo delivery of miR-155 modulates the Viral haemorrhagic septicaemia virus-induced antiviral immune responses in zebrafish (Danio rerio)

Viral haemorrhagic septicaemia virus (VHSV) is one of the highly pathogenic virus, which causes viral haemorrhagic septicaemia disease in both marine and freshwater fish. Micro RNA-155 (miRNA-155) is a multifunctional small non-coding RNA and it involves regulation of immune responses during viral infection. In this study, dre-miR-155 mimics were encapsulated into chitosan nanoparticles (CNPs). Resulted encapsulated product (miR-155-CNPs) was investigated for its immunomodulation role in zebrafish during experimentally challenged VHSV infection. Successful encapsulation of dre-miR-155 mimics into CNPs was confirmed through average nanoparticle (NPs) size (341.45 ± 10.00 nm), increased encapsulation efficiency percentage (98.80%), bound dre-miR-155 with chitosan, sustained release in vitro (up to 40%), and the integrity of RNA. Overexpressed miR-155 was observed in gills, muscle, and kidney tissues (5.42, 19.62, and 140.72-folds, respectively) after intraperitoneal delivery of miR-155-CNPs into zebrafish upon VHSV infection (miR-155-CNPs + VHSV). The miR-155-CNPs + VHSV infected fish had the highest cumulative survival (85%), which was associated with low viral copy numbers. The miR-155-overexpressing fish showed significantly decreased expression of ifnγ, irf2bpl, irf9, socs1a, il10, and caspase3, compared to that of the miR-155 inhibitor + VHSV infected fish group. In contrast, il1β, tnfα, il6, cd8a, and p53 expressions were upregulated in miR-155-overexpressed zebrafish compared to that of the control. The overall findings indicate the successful delivery of dre-miR-155 through miR-155-CNPs that enabled restriction of VHSV infection in zebrafish presumably by modulating immune gene expression.

Dysbiotic microbiome induce cardiac impairment by attenuating brain-derived neurotrophic factor in inflammatory bowel diseases

Abstract Background & Aims Mounting evidence suggests that inflammatory bowel disease (IBD) is associated with increased incidences of cardiovascular diseases (CVD), including myocardial infarction and heart failure. However, the molecular mechanisms by which IBD predisposes patients to CVD are poorly understood. This study aimed to identify the role of dysbiosis in gut-heart crosstalk. Methods Chronic colitis-induced cardiac impairment was assessed in mice subjected to dextran sodium sulfate (DSS), rats treated with trinitrobenzenesulfonic acid, and IL10-/-mice which develop spontaneous colitis after weaning. Fecal microbiota of wild type or IL10-/- mice were transplanted to C57BL/6J mice treated with microbiome-depleting antibiotic cocktail and germ-free mice to determine if dysbiosis afflicts the heart. Heart function was evaluated by echocardiography. Heart transcriptomes were profiled by RNA-sequencing. Gut microbiota profiling was performed by 16S rRNA sequencing. Adverse effect of brain-derived neutrophic factor (BDNF) deficiency on the heart was evaluated in cardiac-specific BDNF knockout mice (BdnfΔheart). Results Impairment of heart function, evidenced by decreased left ventricle ejection fraction (LVEF), increased LV mass, and elevated serum B-type natriuretic peptide, was observed in all 3 models of colitis, providing direct evidence that chronic colitis deteriorates the heart (Figure 1). RNA-sequencing revealed loss of Bdnf and alterations of multiple genes critical to heart homeostasis in the myocardium. Many of the changes, including Bdnf reduction, were found in microbiota-depleted C57BL/6J mice and germ-free mice received dysbiotic fecal microbiome, compared to controls, suggesting that dysbiosis impaired the heart by suppressing Bdnf. BdnfΔheart mice had impaired heart function, including decreased contractility and EF, increased fibrosis, and impaired coronary microcirculation (lower CD31), compared to Bdnf[2lox] mice. Mechanistically, miR-155 in the heart and exosomal miR-29b in the plasma were significantly elevated by chronic colitis. miR-155 and miR-29b mimics suppressed BDNF in cardiomyocytes both in vitro and in vivo. Administration of miR-155 inhibitors or exosomes packaged with miR-29b antagonists ameliorated BDNF reduction in the heart of IL10-/- mice. BDNF supplementation markedly improved heart function in DSS mice. Conclusions Chronic colitis impairs the heart through dysbiosis/miR-29b/miR-155/BDNF signaling axis. Targeting this pathway is a promising strategy to overcome gut dysbiosis harmful for the heart in IBD.

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

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