Exosomal miR-126-3p: Potential protection against vascular damage by regulating the SLC7A5/mTOR Signalling pathway in human umbilical vein endothelial cells.

Systemic sclerosis (SSc) is a chronic autoimmune connective tissue disease. Vascular damage is one of the important features of SSc, which affects the progression and prognosis of the disease. MiR-126-3p is an important microRNA (miRNA) that regulates vascular structure and function, which can be transported through exosomes. However, the role of miR-126-3p in vascular damage in SSc is still unclear. Therefore, we focused on the connection between miR-126-3p and vascular damage in SSc, as well as investigated the potential role of miR-126-3p in vascular damage in SSc. First, this study successfully extracted extracellular vesicles from clinical plasma samples and characterized the exosomes within them. Then, we predicted and screened the target pathway mammalian/mechanistic target of rapamycin (mTOR) and the target gene SLC7A5 of miR-126-3p through online databases. Next, we constructed SSc mice for in vivo studies. The results showed that the expression of miR-126-3p was decreased in the plasma exosomes, while the SLC7A5 expression, autophagy, and lipid peroxidation were increased in the aorta. Luciferase reporter gene assays demonstrated that miR-126-3p can bind to SLC7A5, resulting in a decrease in its expression. In vitro experiments have shown that exosomal miR-126-3p can be internalized by human umbilical vein endothelial cells (HUVECs). The miR-126-3p group exhibited enhanced cell viability and tube formation ability, along with increased expression of the vascular formation marker CD31. Additionally, miR-126-3p downregulated the protein expression of SLC7A5 and LC3 in HUVECs, while upregulating the protein expression of mTOR, P62, PPARγ, and CPT-1. However, the effects of miR-126-3p on HUVECs were counteracted by mTOR inhibitors and enhanced by mTOR activators. The results indicated that exosomal miR-126-3p has the potential to protect against vascular injury in SSc by regulating the SLC7A5/mTOR signalling pathway in HUVECs.

Clinical significance of lncRNA XIST expression in cholangiocarcinoma and its effect on cell migration and invasion.

BACKGROUND: Cholangiocarcinoma is a malignant tumor that occurs in the bile duct system, and the prognosis of patients is poor. Currently, research suggests that long non-coding RNAs (lncRNAs) in the treatment and prevention of cholangiocarcinoma. This study primarily focuses on the regulation and potential mechanism of the lncRNA XIST (XIST) in cholangiocarcinoma. METHODS: The levels of XIST and miR-126-3p in cholangiocarcinoma tissues and cells were detected using real-time quantitative polymerase chain reaction (RT-qPCR). Cell transfection status, including migration and invasion, was examined via the Transwell method. The relationship between XIST and miR-126-3p was observed by dual-luciferase gene reporter assay and verified by rescue assays. Additionally, the prognostic significance of XIST in cholangiocarcinoma was determined using Kaplan-Meier and multivariate Cox regression analyses. RESULTS: XIST expression was increased in cholangiocarcinoma, while miR-126-3p was decreased, in both tissues and cells. The successful construction of silencing XIST was found to inhibit the count of cell migration and invasion. XIST directly targeted miR-126-3p to regulate the progression of cholangiocarcinoma. CONCLUSION: XIST sponging miR-126-3p inhibited the progression of cholangiocarcinoma and improved the prognosis for patients. This finding provides new insights and opportunities for future studies on cholangiocarcinoma prognostic biomarkers.

Long noncoding RNA XIST promotes cell proliferation and migration in diabetic foot ulcers through the miR-126-3p/EGFR axis.

BACKGROUND: The prevalence of diabetic foot ulcers (DFUs) has caused serious harm to human health. To date, a highly effective treatment is lacking. Long noncoding RNA X-inactive specific transcript (lncRNA XIST) has been the subject of mounting research studies, all of which have found that it serves as a protective factor against certain diseases; however, its function in DFUs is not entirely understood. This study was performed to determine the importance of the lncRNA XIST in the pathogenesis and biological function of DFUs. METHODS: Diabetic ulcer skin from rats was analysed using haematoxylin-eosin (HE), Masson's trichrome, and immunohistochemistry (IHC) staining. The differences in the expression of genes and proteins were examined with real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting. Next, the interaction was verified with a dual luciferase gene reporter assay. In addition, CCK-8, Transwell, and wound healing assays were used to assess the proliferation and migration of HaCaT cells. RESULTS: The lncRNA XIST and epidermal growth factor receptor (EGFR) were downregulated, while microRNA-126-3p (miR-126-3p) was increased in diabetic ulcer rat skin tissues and high glucose-induced HaCaT cells. In addition, we found that the lncRNA XIST binds to miR-126-3p and that EGFR is directly targeted by miR­126­3p. Silencing XIST contributed to upregulated miR-126-3p expression, thus lowering EGFR levels and inhibiting the proliferative and migratory abilities of high glucose-treated HaCaT cells; however, the miR-126-3p inhibitor and overexpression of EGFR reversed this effect. CONCLUSION: Decreased lncRNA XIST expression inhibits the proliferative and migratory abilities of high glucose-induced HaCaT cells by modulating the miR-126-3p/EGFR axis, causing delayed wound healing.

IFN-γ enhances the therapeutic efficacy of MSCs-derived exosome via miR-126-3p in diabetic wound healing by targeting SPRED1.

BACKGROUND AND AIMS: The traditional treatment of diabetic wounds is unsatisfactory. Exosomes isolated from bone marrow mesenchymal stem cells (BMSCs) promote the healing of diabetic wounds. However, whether the exosomes secreted by interferon (IFN)-γ-pretreated BMSCs have an enhanced therapeutic effect on diabetic wound healing and the relevant mechanisms remain unclear. METHODS: In this study, we isolated exosomes from the corresponding supernatants of BMSCs with (IExos) or without IFN-γ treatment (NExos). Human umbilical vein endothelial cells (HUVECs) were used to investigate the proliferation, migration, and tube formation under different treatments in vitro. Diabetic mice were induced by intraperitoneal administration of streptozotocin, and a circular full-thickness dermal defect was then made on the back of each mouse, followed by a multisite subcutaneous injection of phosphate buffered saline or exosomes. Hematoxylin-eosin (H&E) staining, Masson's trichrome staining, and histological analysis were performed to assess the speed and quality of wound healing. RESULTS: NExos treatment accelerated the healing of diabetic wounds by promoting angiogenesis in vivo and in vitro, and IExos exhibited superior therapeutic efficiency. MicroRNA (miR)-126-3p was significantly increased in IExos, and exosomal miR-126-3p promoted angiogenesis and diabetic wound healing via its transfer to HUVECs. miR-126-3p regulates SPRED1 by directly targeting the 3'-UTR. Mechanistically, IFN-γ-pretreated BMSCs secreted miR-126-3p-enriched exosomes, which enhanced the function of HUVECs and promoted angiogenesis via the SPRED1/Ras/Erk pathway. CONCLUSION: Exosomal miR-126-3p secreted from IFN-γ-pretreated BMSCs exhibited higher therapeutic efficacy than NExos in diabetic wound healing by promoting angiogenesis via the SPRED1/Ras/Erk axis.

Alterations in Serum miR-126-3p Levels over Time: A Marker of Pituitary Insufficiency following Head Trauma.

INTRODUCTION: Traumatic brain injuries (TBIs) pose a high risk of pituitary insufficiency development in patients. We have previously reported alterations in miR-126-3p levels in sera from patients with TBI-induced pituitary deficiency. METHODS: To investigate why TBI-induced pituitary deficiency develops only in some patients and to reveal the relationship between miR-126-3p with hormone axes, we used mice that were epigenetically modified with miR-126-3p at the embryonic stage. These modified mice were subjected to mild TBI (mTBI) according to the Marmarou's weight-drop model at 2 months of age. The levels of miR-126-3p were assessed at 1 and 30 days in serum after mTBI. Changes in miR-126-3p levels after mTBI of wild-type and miR-126-3p* modified mouse lines validated our human results. Additionally, hypothalamus, pituitary, and adrenal tissues were analyzed for transcripts and associated serum hormone levels. RESULTS: We report that miR-126-3p directly affects hypothalamus-pituitary-adrenal (HPA) axis upregulation and ACTH secretion in the acute phase after mTBI. We also demonstrated that miR-126-3p suppresses Gnrh transcripts in the hypothalamus and pituitary, but this is not reflected in serum FSH/LH levels. The increase in ACTH levels in the acute phase may indicate that upregulation of miR-126-3p at the embryonic stage has a protective effect on the HPA axis after TBI. Notably, the most prominent transcriptional response is found in the adrenals, highlighting their role in the pathophysiology of TBI. CONCLUSION: Our study revealed the role of miR-126-3p in TBI and pituitary deficiency developing after TBI, and the obtained data will significantly contribute to elucidating the mechanism of pituitary deficiency development after TBI and development of new diagnostic and treatment strategies.

Astragaloside IV promotes exosome secretion of endothelial progenitor cells to regulate PI3KR2/SPRED1 signaling and inhibit pyroptosis of diabetic endothelial cells.

BACKGROUND AIMS: Treating chronic non-healing diabetic wounds and achieving complete skin regeneration has always been a critical clinical challenge. METHODS: In order to address this issue, researchers conducted a study aiming to investigate the role of miR-126-3p in regulating the downstream gene PIK3R2 and promoting diabetic wound repair in endothelial progenitor cell (EPC)-derived extracellular vesicles. The study involved culturing EPCs with astragaloside IV, transfecting them with miR-126-3p inhibitor or mock plasmid, interfering with high glucose-induced damage in human umbilical vein endothelial cells (HUVECs) and treating diabetic skin wounds in rats. RESULTS: The healing of rat skin wounds was observed through histological staining. The results revealed that treatment with miR-126-3p-overexpressing EPC-derived extracellular vesicles accelerated the healing of rat skin wounds and resulted in better tissue repair with slower scar formation. In addition, the transfer of EPC-derived extracellular vesicles with high expression of miR-126-3p to high glucose-damaged HUVECs increased their proliferation and invasion, reduced necrotic and apoptotic cell numbers and improved tube formation. In this process, the expression of angiogenic factors vascular endothelial growth factor (VEGF)A, VEGFB, VEGFC, basic fibroblast growth factor and Ang-1 significantly increased, whereas the expression of caspase-1, NRLP3, interleukin-1ß, inteleukin-18, PIK3R2 and SPRED1 was suppressed. Furthermore, miR-126-3p was able to target and inhibit the expression of the PIK3R2 gene, thereby restoring the proliferation and migration ability of high glucose-damaged HUVEC. CONCLUSIONS: In summary, these research findings demonstrate the important role of miR-126-3p in regulating downstream genes and promoting diabetic wound repair, providing a new approach for treating chronic non-healing diabetic wounds.

Global DNA methylation and miR-126-3p expression in Mexican women with gestational diabetes mellitus: a pilot study.

BACKGROUND: Gestational diabetes mellitus (GDM), a type of diabetes that occurs for the first time during pregnancy, may predispose the development of chronic degenerative diseases and metabolic alterations in mother and offspring. DNA methylation and microRNA (miRNA) expression are regulatory mechanisms of gene expression that may contribute to the pathogenesis of GDM. Therefore, we determined global DNA methylation and miR-126-3p expression levels in 8 and 7 Mexican women with and without GDM, respectively. METHODS AND RESULTS: Global DNA methylation was assessed by measuring the percentage of 5-methylcytosine (5-mC) in placenta, umbilical cord, and plasma DNA samples, whereas miR-126-3p expression was quantified by real-time PCR using the 2-ΔCt method of the corresponding RNA samples. A significant increase in the percentage of 5-mC was detected in placenta samples from GDM patients compared to healthy women, while plasma samples showed a significant decrease. Conversely, miR-126-3p expression levels were significantly higher in plasma from the GDM group, while placenta and umbilical cord samples showed no significant differences across experimental groups. Furthermore, DNA methylation correlated significantly with glucose levels in placenta and plasma. Likewise, miR-126-3p expression correlated significantly with plasma glucose, in addition to maternal body mass index (BMI at first trimester). CONCLUSION: The results indicate that GDM is associated with alterations in global DNA methylation levels and miR-126-3p expression in placenta and/or plasma, providing insights into future novel approaches to diagnose and/or prevent this pathology.

Alteration of circulating miRNAs during myocardial infarction and association with lipid levels.

BACKGROUND: Increasing mortality and morbidity of coronary artery disease (CAD) highlight the emerging need for novel noninvasive markers such as circulating microRNAs (miRNAs). OBJECTIVE: To evaluate the circulating levels of miR-126-3p, miR-210-3p, let-7g-5p, and miR-326, and their associations with known contributors to CAD, in CAD subgroups. METHODS: We divided the cohort into 4 groups: non-CAD controls (≤30% stenosis; n = 55), and patients with stable angina pectoris (SAP; n = 48), unstable AP (UAP; n = 46), and myocardial infarction (MI; n = 36). The circulating levels of miR-126-3p, miR-210-3p, let-7g-5p, and miR-326 were determined using TaqMan Advanced miRNA Assays in serum specimens. RESULTS: Circulating miR-126-3p levels were lower in the MI and UAP groups, compared with the non-CAD group, whereas miR-210-3p circulating levels were lower in the MI group than others. The levels of circulating let-7g-5p were shown to be useful for distinguishing UAP from MI, and there were substantial differences in circulating let-7g-5p levels between the UAP and MI groups. Moreover, lipid levels and ratios were lower in individuals with high circulating miR-126-3p and miR-210-3p levels. CONCLUSIONS: The study results suggest that circulating miR-126-3p, miR-210-3p, and let-7g-5p are differentiated between different clinical presentations of CAD and associated with lipid levels, which are important risk factors and determinants of CAD.

Hsa_circ_0002348 regulates trophoblast proliferation and apoptosis through miR-126-3p/BAK1 axis in preeclampsia.

BACKGROUND: Preeclampsia is a common pregnancy complication characterized by high blood pressure and damage to organs. Abnormal placenta and vascular function can lead to preeclampsia. Accumulating evidence has suggested a potential link between circular RNAs (circRNAs) and preeclampsia. As a placenta and endothelial-expressed circRNA, hsa_circ_0002348, may be promising to be the novel molecular target for preeclampsia. However, the function and mechanism of hsa_circ_0002348 in preeclampsia has not been elucidated. MATERIALS AND METHODS: An overlap analysis of two circRNA profiles from placenta and endothelial cells was used to identify a functionally unknown circRNA, hsa_circ_0002348. Quantitative real-time PCR (qRT-PCR) and in situ hybridization (ISH) were used to detect its expression in the trophoblast cells and placental tissues. The mouse model of lipopolysaccharide (LPS)-induced preeclampsia was established to determine the in vivo role of hsa_circ_0002348. RNA immunoprecipitation (RIP), Luciferase reporter assay, qRT-PCR, western blot, gain- and loss-of-function and rescue experiments were conducted to uncover the role of hsa_circ_0002348 and its interaction with miR-126-3p and BAK1 in regulating trophoblast proliferation and apoptosis. Fluorescence in situ hybridization (FISH) and Immunohistochemistry (IHC) were performed to examine the expression of miR-126-3p and BAK1 in mice and human placentas, respectively. RESULTS: Hsa_circ_0002348 was significantly increased in the preeclampsia placentas, and positively correlated with the severity of preeclampsia patients' clinical manifestations. Its overexpression exacerbated preeclampsia-like features in the mouse model of LPS-induced preeclampsia. Functionally, hsa_circ_0002348 was found to inhibit trophoblast proliferation and promote trophoblast apoptosis. Mechanistically, hsa_circ_0002348, as an endogenous miR-126-3p sponge, upregulated the expression of BAK1. Additionally, both hsa_circ_0002348 knockdown and miR-126-3p overexpression enhanced the mammalian target of rapamycin (mTOR) and ERK1/2 signaling pathway. CONCLUSIONS: Hsa_circ_0002348 might be a novel regulator of trophoblast proliferation and apoptosis through miR-126-3p/BAK1 axis in preeclampsia, which may serve as a potential target for detecting and treating preeclampsia.

Mechanism of human chorionic gonadotropin in endometrial receptivity via the miR-126-3p/PI3K/Akt/eNOS axis.

Human chorionic gonadotropin (hCG) might affect endometrial receptivity, exerting integral roles in embryo implantation. This study explored the action of hCG in endometrial receptivity via the miR-126-3p/PIK3R2/PI3K/Akt/eNOS axis. The embryo implantation dysfunction (EID) mouse models were established by administrating mifepristone and human endometrial epithelial cells (EECs) were used for in vivo experiments, both followed by hCG treatment. Expression level of CD105 and protein levels of cadherin CD144 and CD146 in mice were determined by immunohistochemistry and Western blot. The levels of miR-126-3p and PIK3R2 mRNA and PIK3R2, p-PI3K p85 α, PI3K p110 α, p-Akt, Akt, p-eNOS, and eNOS protein levels were measured. Cell proliferation was evaluated by CCK-8 and EdU assays. The binding sites of miR-126-3p and PIK3R2 were predicted and verified. hCG-treated EECs were further transfected with miR-126-inhibitor for functional rescue experiments. hCG ameliorated endometrial receptivity in EID mice. Moreover, hCG promoted miR-126-3p and suppressed PIK3R2 in EID mice and EECs. miR-126-3p targeted PIK3R2. EEC proliferation was enhanced after hCG treatment but inhibited by miR-126-3p downregulation. Both in vivo and in vitro experiments validated that hCG activated the PI3K/Akt/eNOS pathway through the miR-126-3p/PIK3R2 axis. Collectively, hCG improves endometrial receptivity by activating the PI3K/Akt/eNOS pathway via regulating miR-126-3p/PIK3R2.

Extracellular vesicle­mediated miR­126­3p transfer contributes to inter­cellular communication in the liver tumor microenvironment.

Extracellular vesicles (EVs) and their contents are gaining recognition as important mediators of intercellular communication through the transfer of bioactive molecules, such as non­coding RNA. The present study comprehensively assessed the microRNA (miRNA/miR) content within EVs released from HepG2 liver cancer (LC) cells and LX2 hepatic stellate cells (HSCs) and determined the contribution of EV miRNA to intercellular communication. Using both transwell and spheroid co­cultures of LC cells and HSCs, miR­126­3p within EV was established as a mediator of HSC to LC cell communication that influenced tumor cell migration and invasion, as well as the growth of multicellular LC/HSC spheroids. Manipulation of miR­126­3p either by enforced expression using pre­miR­126­3p or by inhibition using antimiR­126­3p did not alter tumor cell viability, proliferation or sensitivity to either sorafenib or regorafenib. By contrast, enforced expression of miR­126­3p decreased tumor­cell migration. Knockdown of miR­126­3p in tumor cells increased disintegrin and metalloproteinase domain­containing protein 9 (ADAM9) expression and in HSCs increased collagen­1A1 accumulation with an increase in compactness of multicellular spheroids. Within LC/HSC spheroids, ADAM9 and vascular endothelial growth factor expression was increased by silencing of miR­126­3p but diminished with the restoration of miR­126­3p. These studies implicate miR­126­3p in functional effects on migration, invasion and spheroid growth of tumor cells in the presence of HSCs, and thereby demonstrate functional EV­RNA­based intercellular signaling between HSCs and LC cells that is directly relevant to tumor­cell behavior.

The expression of circulating hsa-miR-126-3p in dengue-infected Thai pediatric patients.

Circulating hsa-miRNA-126 (CmiR-126) has been reported to involve in the pathogenesis of many infectious diseases including dengue virus infection. However, no prior study has been conducted to describe more details in dengue-infected pediatric patients. This study aimed to describe CmiR-126-3p in dengue-infected pediatric patients during the febrile and convalescent phases. Additionally, the correlations between CmiR-126-3p and other relevant clinical laboratory factors were investigated. Sixty paired-serum specimens collected during febrile and convalescent phases were retrieved from patients with dengue fever (DF) (n = 30) and dengue hemorrhagic fever (DHF) (n = 30). Thirty paired-serum specimens collected from non-dengue acute febrile illness patients (AFI) were included as the control group. CmiR-126-3p was determined using reverse transcription quantitative real-time polymerase-chain reaction (RT-qPCR). Relative miRNA expression was calculated as 2-ΔCt using CmiR-16-5p for data normalization. CmiR-126-3p expression during febrile and convalescent phases in dengue-infected patients was significantly lower than AFI (p < 0.05). However, miRNA levels were not different (p > 0.05) compared between DF and DHF and between primary and secondary infection. CmiR-126-3p levels in DF in the convalescent were significantly higher than in the febrile phase (p = 0.025). No association between CmiR-126-3p and hematocrit, WBC level, platelet count, WBC differential count or dengue viral load was observed (p > 0.05). The data suggest that hsa-miR-126-3p involved in pathogenesis of dengue infection and may be a promising early and late biomarker for DENV infection. However, hsa-miR-126-3p alone cannot be used as a predictor for dengue severity.

Hydrogen Sulfide Improves Angiogenesis by Regulating the Transcription of pri-miR-126 in Diabetic Endothelial Cells.

INTRODUCTION: Diabetes mellitus results in high rates of cardiovascular disease, such as microcirculation disorder of the lower limbs, with angiogenesis impairment being the main factor. The endothelium functions as a barrier between blood and the vessel wall. Vascular endothelial cell dysfunction caused by hyperglycemia is the main factor leading to angiogenesis impairment. Hydrogen sulfide (H2S) and miR-126-3p are known for their pro-angiogenesis effects; however, little is known about how H2S regulates miR-126-3p to promote angiogenesis under high-glucose conditions. OBJECTIVES: The main objective of this research was to explore how H2S regulates the miR-126-3p levels under high-glucose conditions. METHODS: We evaluated the pro-angiogenesis effects of H2S in the diabetic hindlimb of an ischemia mice model and in vivo Matrigel plugs. Two microRNA datasets were used to screen microRNAs regulated by both diabetes and H2S. The mRNA and protein levels were detected through real-time PCR and Western blot, respectively. Immunofluorescent staining was also used to assess the capillary density and to evaluate the protein levels in vascular endothelial cells. Human umbilical vein endothelial cells (HUVECs) were used in in vitro experiments. A scratch wound-healing assay was applied to detect the migration ability of endothelial cells. Methylated DNA immunoprecipitation combined with real-time PCR was chosen to identify the DNA methylation level in the HUVECs. RESULTS: Exogenous H2S improved angiogenesis in diabetic mice. miR-126-3p was regulated by both diabetes and H2S. Exogenous H2S up-regulated the miR-126-3p level and recovered the migration rate of endothelial cells via down-regulating the DNMT1 protein level, which was increased by high glucose. Furthermore, DNMT1 upregulation in the HUVECs increased the methylation levels of the gene sequences upstream of miR-126-3p and then inhibited the transcription of primary-miR-126, thus decreasing the miR-126-3p level. CSE overexpression in the HUVECs rescued the miR-126-3p level, by decreasing the methylation level to improve migration. CONCLUSION: H2S increases the miR-126-3p level through down-regulating the methylation level, by decreasing the DNMT1 protein level induced by high glucose, thus improving the angiogenesis originally impaired by high glucose.

MEK1/2 inhibitor inhibits neointima formation by activating miR-126-3p/ C-X-C motif chemokine ligand 12 (CXCL12)/C-X-C motif chemokine receptor 4 (CXCR4) axis.

Endothelial dysfunction is an initial and essential step in vascular-remodeling diseases, including atherosclerosis and neointima formation. During vascular remodeling, activated endothelial cells can release pro-inflammatory factors that promote phenotypic switching of vascular smooth muscle cells (VSMCs) to the proliferative phenotype. We previously reported that MEK1/2 inhibitor, U0126, has a protective effect on the development of atherosclerosis and vascular calcification. However, the effect of MEK1/2 inhibitors on neointimal formation and the underlying mechanism is not fully understood. We determined that MEK1/2 inhibitor reduced carotid artery ligation-induced neointimal formation, while increased collagen and elastin levels and vascular integrality. Mechanistically, MEK1/2 inhibitor or ERK1/2 siRNA increased miR-126-3p level in endothelial cells, thereby inhibiting expression of regular of G-protein signaling 16 (RGS16), a miR-126-3p target gene, to activate the C-X-C motif chemokine ligand 12 (CXCL12)/C-X-C motif chemokine receptor 4 (CXCR4) signaling pathway. Accordingly, miR-126-3p was also increased by U0126 in serum and carotid artery. RGS16 was inhibited while CXCR4 and CXCL12 was increased by U0126 in neointimal areas, especially in the endothelium. Moreover, similar results were observed in atherosclerotic plaques of high-fat diet-fed apolipoprotein E deficiency (apoE-/-) mice. In addition, vascular cell adhesion molecule 1 (VCAM-1), another miR-126-3p target gene, was reduced by U0126 in the neointimal areas, resulting reduced monocytes/macrophages accumulation. Taken together, our results indicate that MEK1/2 inhibitor can reduce neointima formation by activating endothelial miR-126-3p production to facilitate endothelium repair while reduce monocyte adhesion/infiltration.

Peripheral Serum Exosomes Isolated from Patients with Acute Myocardial Infarction Promote Endothelial Cell Angiogenesis via the miR-126-3p/TSC1/mTORC1/HIF-1α Pathway.

Purpose: Angiogenesis is required for improving myocardial function and is a key factor in long-term prognosis after an acute myocardial infarction (AMI). Although exosomes are known to play a crucial role in angiogenesis, the role of peripheral exosomes in angiogenic signal transduction in patients with AMI remains unclear. Here, we explored the effect of exosomes extracted from the peripheral serum of AMI patients on angiogenesis and elucidated the downstream pathways. Patients and Methods: Serum exosomes were obtained from patients with AMI (AMI-Exo) and healthy individuals (Con-Exo). The exosomes were cocultured with human umbilical vein endothelial cells (HUVECs) in vitro, with aortic rings ex vivo, and were used to treat mouse hind-limb ischemia and mouse AMI model in vivo. Results: AMI-Exo raised HUVEC proliferation, tube formation, and migration, and enhanced microvessel sprouting from aortic rings compared to Con-Exo, both in vitro and ex vivo. Quantitative reverse transcription-polymerase chain reaction revealed that the abundance of miR-126-3p, a crucial regulator of angiogenesis, was increased in AMI-Exo. The inhibition of miR-126-3p decreased the benefits of AMI-Exo treatment, and miR-126-3p upregulation enhanced the benefits of Con-Exo treatment in HUVECs, aortic rings, the mouse hind-limb ischemia model, and the mouse AMI model. Knockdown and overexpression analyses revealed that miR-126-3p regulated angiogenesis in HUVECs by directly targeting tuberous sclerosis complex 1 (TSC1). Moreover, we found that miR-126-3p could inhibit TSC1 expression, which further activated mTORC1 signaling and increased HIF-1α and VEGFA expression, ultimately promoting angiogenesis. Conclusion: Collectively, our results provide a novel understanding of the function of exosomes in angiogenesis post AMI. We demonstrated that exosomes from the peripheral serum of AMI patients promote angiogenesis via the miR-126-3p/TSC1/mTORC1/HIF-1α signaling pathway.

Circulating miRNAs in girls with abdominal obesity: miR-221-3p as a biomarker of response to weight loss interventions.

BACKGROUND: Recent studies have associated several microRNAs (miRNAs) with childhood obesity and energy homeostasis, suggesting that an individual miRNA profile could be used as an early predictor to estimate the response to weight loss interventions in the design of precision nutrition. OBJECTIVE: To investigate associations between the expression of circulating adiposity-related miRNAs and the response to a weight loss intervention. METHODS: A total of 51 Spanish girls (age 7-16 years) with abdominal obesity underwent 8 weeks of a multidisciplinary intervention for weight loss. Participants were stratified into two groups in accordance with changes in body mass index (BMI) standard deviation score: low-responders (LR) and high-responders (HR). The expression of 39 circulating miRNAs (c-miRNAs) was evaluated in plasma of all subjects before the intervention. RESULTS: Six miRNAs were differentially expressed between LR and HR. However, after adjustment for Tanner stage, the association was maintained only for miR-126-3p and miR-221-3p with a higher expression in HR group compared to LR group. After the intervention, miR-221-3p expression decreased in all subjects with a significant difference in the change within groups. However, changes in miR-126-3p levels were not significant. The expression of miR-221-3p was positively correlated with body weight, BMI and waist circumference, and negatively correlated with quantitative insulin sensitivity check index. CONCLUSIONS: Bioinformatic analysis evidenced that miR-221-3p participates in several obesity-related pathways, and more interestingly, this miRNA targets several candidate genes to childhood obesity according to DisGeNet database. Thus, miR-221-3p could be used for predicting the response to a multidisciplinary intervention for weight loss in young girls.

Circulating miR-126-3p and miR-423-5p Expression in de novo Adult Acute Myeloid Leukemia: Correlations with Response to Induction Therapy and the 2-Year Overall Survival.

BACKGROUND: Acute myeloid leukemia (AML) results from sequential genetic alterations in a normal hematopoietic stem cell or its progenitors giving rise to an autonomous clone that dominates the bone marrow leading to marrow failure. MicroRNAs are short non-coding nucleic acid sequences that regulate post-transcriptional gene expression by base-pairing with their target mRNAs. MiRNAs can be secreted into extracellular fluids and carried to target cells by vesicles or bound to proteins. Intracellular and circulating miRNAs are believed to be useful markers in the diagnosis, prognosis, and treatment of various cancers. Practically, circulating miRNAs are more stable at room temperatures and extreme conditions. PURPOSE: This study aimed to compare the expression of miR-126-3p and miR-423-5p in patients and normal subjects and correlate their expression with response to induction therapy and with their 2-year overall survival rate. PATIENTS AND METHODS: Circulating miR-126-3p and miR-423-5p was measured in the plasma of 43 adult AML patients and 35 age- and sex-matched controls by quantitative reverse transcriptase PCR. The fold change in differential expression for each gene was calculated using the comparative cycle threshold method. RESULTS: There was an increase in the expression of the studied miRNAs in patients compared to the control group. The average expression fold change of miR-126-3p was 3.02 (p= 0.010). The average expression fold change of miR-423-5p was 4.09 (p= 0.003). No significant correlation was found between the expression of miR-126-3p and miR-423-5p in the studied AML patients (r = 0.094, p = 0.22). Furthermore, no relationship was found between the expression of the studied miRNAs and response to induction therapy or the 2-year survival rate. CONCLUSION: Although further studies are needed, our findings highlight the studied circulating miRNAs as possible diagnostic markers for AML.

miRNA-126a-3p participates in hippocampal memory via alzheimer's disease-related proteins.

Memory formation and consolidation necessitate gene expression and new protein synthesis. MicroRNAs (miRNAs), a family of small noncoding RNAs that inhibit target gene mRNA expression, are involved in new memory formation. In this study, elevated miR-126a-3p (miR-126) levels were found to contribute to the consolidation of contextual fear memory. Using different commonly mined algorithms and luciferase reporter assay, we found two Alzheimer's disease (AD)-related proteins, namely EFHD2 and BACE1, but not ADAM9, were the targets downregulated by miR-126 after CFC training. Moreover, we indicated that upregulated miR-126 could promote the formation of contextual fear memory by modulating its target EFHD2. Finally, we demonstrated that miR-126 overexpression in dentate gyrus of hippocampus could reduce Aß plaque area and neuroinflammation, as well as rescue the hippocampal memory deficits in APP/PS1 mice. This study adds to the growing body of evidence for the role of miRNAs in memory formation and demonstrates the implication of EFHD2 protein regulated by miR-126 in the adult brain.

Investigation of miR-126-3p loaded on adipose stem cell-derived exosomes for wound healing of full-thickness skin defects.

OBJECTIVE: To investigate the function of miR-126-3p loaded on adipose stem cell (ADSC)-derived exosomes (ADSC-Exos) in wound healing of full-thickness skin defects. METHODS: ADSCs transfected with miR-126-3p mimic, miR-126-3p inhibitor or pcDNA3.1-PIK3R2, or PKH26-marked ADSC-Exos were cultured with fibroblasts or human umbilical vein endothelial cells (HUVECs). The proliferation and migration rates of fibroblasts and angiogenesis of HUVECs were measured. Rats with full-thickness skin defects were injected with ADSC-Exos or exosomes extracted from ADSCs transfected with miR-126-3p inhibitor and the wound healing rates were measured. The wound bed, collagen deposition and angiogenesis in injured rats were assessed. RESULTS: ADSC-Exos could be ingested by fibroblasts and HUVECs. Co-incubation with ADSCs or ADSC-Exos promoted the proliferation and migration of fibroblasts and angiogenesis of HUVECs, which was further enhanced by miR-126-3p overexpression. Inhibition of ADSC-Exos or miR-126-3p or PIK3R2 overexpression suppressed the proliferation and migration of fibroblasts and angiogenesis of HUVECs. ADSC-derived exosomal miR-126-3p increased wound healing rate, collagen deposition and newly formed vessels in the injured rats. CONCLUSION: ADSC-derived exosomal miR-126-3p promotes wound healing of full-thickness skin defects by targeting PIK3R2.

Expression Profiles of Circulating microRNAs in South African Type 2 Diabetic Individuals on Treatment.

Aim: The influence of disease duration and anti-diabetic treatment on epigenetic processes has been described, with limited focus on interactions with microRNAs (miRNAs). miRNAs have been found to play key roles in the regulation of pathways associated with type 2 diabetes mellitus (T2DM), and expression patterns in response to treatment may further promote their use as therapeutic targets in T2DM and its associated complications. We therefore aimed to investigate the expressions of circulating miRNAs (miR-30a-5p, miR-1299, miR-182-5p, miR-30e-3p and miR-126-3p) in newly diagnosed and known diabetics on treatment, in South Africa. Methods: A total of 1254 participants with an average age of 53.8years were included in the study and classified according to glycaemic status (974 normotolerant, 92 screen-detected diabetes and 188 known diabetes). Whole blood levels of miR-30a-5p, miR-1299, miR-182-5p, miR-30e-3p and miR-126-3p were quantitated using RT-qPCR. Expression analysis was performed and compared across groups. Results: All miRNAs were significantly overexpressed in subjects with known diabetes when compared to normotolerant individuals, as well as known diabetics vs. screen-detected (p<0.001). Upon performing regression analysis, of all miRNAs, only miR-182-5p remained associated with the duration of the disease after adjustment for type of treatment (OR: 0.127, CI: 0.018-0.236, p=0.023). Conclusion: Our findings revealed important associations and altered expression patterns of miR-30a-5p, miR-1299, miR-182-5p, miR-30e-3p and miR-126-3p in known diabetics on anti-diabetic treatment compared to newly diagnosed individuals. Additionally, miR-182-5p expression decreased with increasing duration of T2DM. Further studies are, however, recommended to shed light on the involvement of the miRNA in insulin signalling and glucose homeostasis, to endorse its use as a therapeutic target in DM and its associated complications.