MicroRNA-210-3p Targets RGMA to Enhance the Angiogenic Functions of Endothelial Progenitor Cells Under Hypoxic Conditions

Modeling of culture conditions by culture system, glucose and propionic acid and their impact on metabolic profile in IPEC-J2

The microbiological environment and their corresponding secreted metabolite spectrum are an essential modulator of the enterocyte function, effecting the whole organism. Intestinal porcine jejunal epithelial cell line (IPEC-J2) is an established in vitro model for differentiation of enterocytes in different cell culture models. An improved oxygen supply seems to be the main reason for differentiation in an air-liquid-interface culture, but this has not yet been conclusively clarified. In this context, the nutrition of the cell and its influence on the metabolism is also of crucial importance. The interest in short-chain fatty acids (SCFAs) has grown steadily in recent years due to their clinical relevance in certain diseases such as multiple sclerosis and other inflammatory diseases, but not much is known of FFAR2 and FFAR3 (free fatty acid receptor 2 and 3) in pigs. We want to address the questions: 1. about the distribution of FFAR2 and FFAR3 in vivo and in vitro in sus scrofa 2. whether there is an influence of propionic acid, glucose content and cultivation on metabolism of enterocytes? The morphological analysis of FFAR2 and FFAR3 in vivo was investigated through immunostaining of frozen sections of the porcine gut segments jejunum, ileum and colon. Both receptors are expressed along the gut and were found in the smooth muscle cells of the tunica muscularis and lamina muscularis mucosae. Furthermore, a high expression of FFAR2 and a low expression of FFAR3 in the enteric nerve system was also observed in jejunum, ileum and colon of sus scrofa. In addition, FFAR2 and FFAR3 within the vessels was investigated. FFAR3 showed a strong expression on endothelial cells of veins and lymphatic vessels but was not detectable on arteries. Furthermore, we demonstrate for the first time, FFAR2 and FFAR3 in IPEC-J2 cells on RNA- and protein level, as well as with confocal microscopy. In addition, ENO1 and NDUFA4 were investigated on RNA-level in IPEC-J2 cells as 2 important genes, which play an essential role in metabolism. Here, NDUFA4 is detected in the model animal sus scrofa as well as in the porcine cell line IPEC-J2. A potential impact of propionic acid and/or glucose and/or cultivation method on the metabolism of the cells was tested with the Seahorse analyzer. Here, a significant higher ECAR was observed in the SMC than in the OCR. In summary, we were able to show that the cultivation system appears to have a greater influence than the medium composition or nutrition of the cells. However, this can be modulated by incubation time or combination of different SCFAs.

Three-Dimensional Mechanical Microenvironment Rescued the Decline of Osteogenic Differentiation of Old Human Jaw Bone Marrow Mesenchymal Stem Cells

Resorption and atrophy of the alveolar bone, as two consequences of osteoporosis that remarkably complicate the orthodontic and prosthodontic treatments, contribute to the differentiated biological features and force-induced response of jaw bone marrow-derived mesenchymal stem cells (JBMSCs) in elderly patients. We isolated and cultured JBMSCs from adolescent and adult patients and then simulated the loading of orthodontic tension stress by constructing an in vitro three-dimensional (3D) stress loading model. The decline in osteogenic differentiation of aged JBMSCs was reversed by tensile stress stimulation. It is interesting to note that tension stimulation had a stronger effect on the osteogenic differentiation of elderly JBMSCs compared to the young ones, indicating a possible mechanism of aging rescue. High-throughput sequencing of microRNA (miRNAs) was subsequently performed before and after tension stimulation in all JBMSCs, followed by the comprehensive comparison of mechanically responsive miRNAs in the 3D strain microenvironment. The results suggested a significant reduction in the expression of miR-210-3p and miR-214-3p triggered by the 3D strain microenvironment in old-JBMSCs. Bioinformatic analysis indicated that both miRNAs participate in the regulation of critical pathways of aging and cellular senescence. Taken together, this study demonstrated that the 3D strain microenvironment efficiently rescued the cellular senescence of old-JBMSCs via modulating specific miRNAs, which provides a novel strategy for coordinating periodontal bone loss and regeneration of the elderly.

miR-29 as diagnostic biomarkers for tuberculosis: a systematic review and meta-analysis

Background

The timely diagnosis of tuberculosis through innovative biomarkers that do not rely on sputum samples is a primary focus for strategies aimed at eradicating tuberculosis. miR-29 is an important regulator of tuberculosis pathogenesis. Its differential expression pattern in healthy, latent, and active people who develop tuberculosis has revealed its potential as a biomarker in recent studies. Therefore, a systematic review and meta-analysis were performed for the role of miR-29 in the diagnosis of tuberculosis.

Methods

EMBASE, PubMed, CNKI, Web of Science, and Cochrane Library databases were searched utilizing predefined keywords for literature published from 2000 to February 2024.Included in the analysis were studies reporting on the accuracy of miR-29 in the diagnosis of tuberculosis, while articles assessing other small RNAs were not considered. All types of study designs, including case-control, cross-sectional, and cohort studies, were included, whether prospectively or retrospectively sampled, and the quality of included studies was determined utilizing the QUADAS-2 tool. Publication bias was analyzed via the construction of funnel plots. Heterogeneity among studies and summary results for specificity, sensitivity, and diagnostic odds ratio (DOR) are depicted in forest plots.

Results

A total of 227 studies were acquired from the various databases, and 18 articles were selected for quantitative analysis. These articles encompassed a total of 2,825 subjects, primarily sourced from the Asian region. Patient specimens, including sputum, peripheral blood mononuclear cells, cerebrospinal fluid and serum/plasma samples, were collected upon admission and during hospitalization for tuberculosis testing. miR-29a had an overall sensitivity of 82% (95% CI 77, 85%) and an overall specificity of 82% (95% CI 78, 86%) for detecting tuberculosis. DOR was 21 (95% CI 16-28), and the area under the curve was 0.89 (95% CI 0.86, 0.91). miR-29a had slightly different diagnostic efficacy in different specimens. miR-29a showed good performance in both the diagnosis of pulmonary tuberculosis and extrapulmonary tuberculosis. miR-29b and miR-29c also had a good performance in diagnosis of tuberculosis.

Conclusion

As can be seen from the diagnostic performance of miR-29, miR-29 can be used as a potential biomarker for the rapid detection of tuberculosis.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=461107.

MicroRNA Expression Profile in Acute Ischemic Stroke

Introduction

Acute ischemic stroke with large vessel occlusion (LVO) continues to present a considerable challenge to global health, marked by substantial morbidity and mortality rates. Although definitive diagnostic markers exist in the form of neuroimaging, their expense, limited availability, and potential for diagnostic delay can often result in missed opportunities for life-saving interventions. Despite several past attempts, research efforts to date have been fraught with challenges likely due to multiple factors such as inclusion of diverse stroke types, variable onset intervals, differing pathobiologies, and a range of infarct sizes, all contributing to inconsistent circulating biomarker levels. In this context, microRNAs (miRNAs) have emerged as a promising biomarker, demonstrating potential as biomarkers across various diseases, including cancer, cardiovascular conditions, and neurological disorders. These circulating miRNAs embody a wide spectrum of pathophysiological processes, encompassing cell death, inflammation, angiogenesis, neuroprotection, brain plasticity, and blood-brain barrier integrity. This pilot study explores the utility of circulating exosome-enriched extracellular vesicle (EV) miRNAs as potential biomarkers for anterior circulation LVO (acLVO) stroke.

Methods

In our longitudinal prospective cohort study, we collected data from acute large vessel occlusion (acLVO) stroke patients at four critical time intervals post-symptom onset: 0-6 hours, 6-12 hours, 12-24 hours, and 5-7 days. For comparative analysis, healthy individuals were included as control subjects. In this study, extracellular vesicles (EVs) were isolated from the plasma of participants, and the miRNAs within these EVs were profiled utilizing the NanoString nCounter system. Complementing this, a scoping review was conducted to examine the roles of specific miRNAs such as miR-140-5p, miR-210-3p, and miR-7-5p in acute ischemic stroke (AIS). This review involved a targeted PubMed search to assess their influence on crucial pathophysiological pathways in AIS, and their potential applications in diagnosis, treatment, and prognosis. The review also included an assessment of additional miRNAs linked to stroke.

Results

Within the first 6 hours of symptom onset, three specific miRNAs (miR-7-5p, miR-140-5p, and miR-210-3p) exhibited significant differential expression compared to other time points and healthy controls. These miRNAs have previously been associated with neuroprotection, cellular stress responses, and tissue damage, suggesting their potential as early markers of acute ischemic stroke.

Conclusion

This study highlights the potential of circulating miRNAs as blood-based biomarkers for hyperacute acLVO ischemic stroke. However, further validation in a larger, risk-matched cohort is required. Additionally, investigations are needed to assess the prognostic relevance of these miRNAs by linking their expression profiles with radiological and functional outcomes.

HypoxamiR-210-3p regulates mesenchymal stem cells proliferation via P53 & Akt

Transplanted stem cells (˃95%) into ischemic myocardium die because of unfavourable conditions. Moreover, hypoxia role in the cell cycle regulation has been studied in transformed/immortalized cell lines which may have altered cell cycle regulators and/or mutated and, can't be transplanted in patients. We quest to find out the mechanism of cell cycle regulation in mesenchymal stem cells (MSC) to regulate its survival and proliferation in repair processes. Additionally, critically analysed role of hypoxamiR-210-3p, and cell cycle regulators that can regulate cell proliferation under hypoxic conditions. Bone marrow-derived MSC (BM-MSC) isolated from young male Fischer-344 rats by flushing the cavity of femur and propagated in vitro under 1% hypoxia for 72 h showed an increased in cell proliferation ([Formula: see text] 30%, p < 0.05) compared to normoxia. miR-210-3p, role in cell proliferation under hypoxic condition was confirmed by knockdown. Loss of function studies with transfection of anti-mir-210-3p, we observed decrease in proliferation of BM-MSC under hypoxia. Furthermore, BM-MSC proliferation due to miR-210-3p was confirmed using CFSE assay and flow cytometry, in which more cells were observed in S-phase. Mechanistically, western blot analysis showed miR-210-3p inhibition upregulates p53 and p21 expression and subsequent decrease in pAkt under hypoxia. On contrary, CFSE and Western blot under normoxic conditions showed downregulation of p53 and p21 whilst upregulation of pAkt indicated the key role of miR-210-3p in BM-MSC proliferation. Our results demonstrate the role of miR-210-3p in BM-MSC proliferation under both hypoxic and normoxic conditions and illustrate the potential mechanism via the regulation of pAkt, p53 and p21.

Targeting oral tumor microenvironment for effective therapy

Oral cancers are among the common head and neck malignancies. Different anticancer therapy modalities such as chemotherapy, immunotherapy, radiation therapy, and also targeted molecular therapy may be prescribed for targeting oral malignancies. Traditionally, it has been assumed that targeting malignant cells alone by anticancer modalities such as chemotherapy and radiotherapy suppresses tumor growth. In the last decade, a large number of experiments have confirmed the pivotal role of other cells and secreted molecules in the tumor microenvironment (TME) on tumor progression. Extracellular matrix and immunosuppressive cells such as tumor-associated macrophages, myeloid-derived suppressor cells (MDSCs), cancer-associated fibroblasts (CAFs), and regulatory T cells (Tregs) play key roles in the progression of tumors like oral cancers and resistance to therapy. On the other hand, infiltrated CD4 + and CD8 + T lymphocytes, and natural killer (NK) cells are key anti-tumor cells that suppress the proliferation of malignant cells. Modulation of extracellular matrix and immunosuppressive cells, and also stimulation of anticancer immunity have been suggested to treat oral malignancies more effectively. Furthermore, the administration of some adjuvants or combination therapy modalities may suppress oral malignancies more effectively. In this review, we discuss various interactions between oral cancer cells and TME. Furthermore, we also review the basic mechanisms within oral TME that may cause resistance to therapy. Potential targets and approaches for overcoming the resistance of oral cancers to various anticancer modalities will also be reviewed. The findings for targeting cells and potential therapeutic targets in clinical studies will also be reviewed.

Extracellular Vesicles from NMN Preconditioned Mesenchymal Stem Cells Ameliorated Myocardial Infarction via miR-210-3p Promoted Angiogenesis

Mesenchymal stem cell-derived extracellular vesicles (MSCs-EVs) possess cardioprotection in acute myocardial infarction. Nevertheless, the therapeutic intervention potential and the molecular mechanism of EVs from NMN (Nicotinamide mononucleotide) preconditioned hUCMSCs (N-EVs) in acute myocardial infarction remains unknown. In the present study, EVs from hUCMSCs (M-EVs) and N-EVs were identified by electron microscopy, immunoblotting and nanoparticle tracking analysis. Compared with M-EVs, N-EVs significantly increased the proliferation, migration, and angiogenesis of HUVECs. Meanwhile, N-EVs markedly reduced apoptosis and cardiac fibrosis and promoted angiogenesis in the peri-infarct region in the MI rats. A high-throughput miRNA sequencing and qPCR methods analysis revealed that miR-210-3p was abundant in N-EVs and the expression of miR-210-3p was obviously upregulated in HUVECs after N-EVs treated. Overexpression of miR-210-3p in HUVECs significantly enhanced the tube formation, migration and proliferative capacities of HUVECs. However, downregulation of miR-210-3p in HUVECs markedly decreased the tube formation, migration and proliferative capacities of HUVECs. Furthermore, bioinformatics analysis and luciferase assays revealed that EphrinA3 (EFNA3) was a direct target of miR-210-3p. Knockdown of miR-210-3p in N-EVs significantly impaired its ability to protect the heart after myocardial infarction. Altogether, these results indicated that N-EVs promoted the infarct healing through improvement of angiogenesis by miR-210-3p via targeting the EFNA3. Created with Biorender.com.

Recombinant Human Arresten and Canstatin Inhibit Angiogenic Behaviors of HUVECs via Inhibiting the PI3K/Akt Signaling Pathway

Angiogenetic inhibitors are crucial in tumor therapy, and endogenous angiogenesis inhibitors have attracted considerable attention due to their effectiveness, safety, and multi-targeting ability. Arresten and canstatin, which have anti-angiogenesis effects, are the c-terminal fragments of the α1 and α2 chains of type IV collagen, respectively. In this study, human arresten and canstatin were recombinantly expressed in Escherichia coli (E. coli), and their effects on the proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVECs) were evaluated. Regarding the cell cycle distribution test and 5-ethynyl-2′-deoxyuridine (EdU) assays, arresten and canstatin could repress the proliferation of HUVECs at a range of concentrations. Transwell assay indicated that the migration of HUVECs was significantly decreased in the presence of arresten and canstatin, while tube formation assays suggested that the total tube length and junction number of HUVECs were significantly inhibited by these two proteins; moreover, they could also reduce the expression of vascular endothelial growth factor (VEGF) and the phosphorylation levels of PI3K and Akt, which indicated that the activation of the 3-kinase/serine/threonine-kinase (PI3K/Akt) signaling pathway was inhibited. These findings may have important implications for the soluble recombinant expression of human arresten and canstatin, and for the related therapy of cancer.

Regulation of Endothelial Progenitor Cell Functions in Ischemic Heart Disease: New Therapeutic Targets for Cardiac Remodeling and Repair

Ischemic heart disease (IHD) is the leading cause of morbidity and mortality worldwide. Ischemia and hypoxia following myocardial infarction (MI) cause subsequent cardiomyocyte (CM) loss, cardiac remodeling, and heart failure. Endothelial progenitor cells (EPCs) are involved in vasculogenesis, angiogenesis and paracrine effects and thus have important clinical value in alternative processes for repairing damaged hearts. In fact, this study showed that the endogenous repair of EPCs may not be limited to a single cell type. EPC interactions with cardiac cell populations and mesenchymal stem cells (MSCs) in ischemic heart disease can attenuate cardiac inflammation and oxidative stress in a microenvironment, regulate cell survival and apoptosis, nourish CMs, enhance mature neovascularization, alleviate adverse ventricular remodeling after infarction and enhance ventricular function. In this review, we introduce the definition and discuss the origin and biological characteristics of EPCs and summarize the mechanisms of EPC recruitment in ischemic heart disease. We focus on the crosstalk between EPCs and endothelial cells (ECs), smooth muscle cells (SMCs), CMs, cardiac fibroblasts (CFs), cardiac progenitor cells (CPCs), and MSCs during cardiac remodeling and repair. Finally, we discuss the translation of EPC therapy to the clinic and treatment strategies.

miR-210 hypoxamiR in Angiogenesis and Diabetes

Significance: microRNA-210 (miR-210) is the master hypoxia-inducible miRNA (hypoxamiR) since it has been found to be significantly upregulated under hypoxia in a wide range of cell types. Recent advances: Gene ontology analysis of its targets indicates that miR-210 modulates several aspects of cellular response to hypoxia. Due to its high pleiotropy, miR-210 not only plays a protective role by fine-tuning mitochondrial metabolism and inhibiting red-ox imbalance and apoptosis, but it can also promote cell proliferation, differentiation, and migration, substantially contributing to angiogenesis. Critical issues: As most miRNAs, modulating different gene pathways, also miR-210 can potentially lead to different and even opposite effects, depending on the physio-pathological contexts in which it acts. Future direction: The use of miRNAs as therapeutics is a fast growing field. This review aimed at highlighting the role of miR-210 in angiogenesis in the context of ischemic cardiovascular diseases and diabetes in order to clarify the molecular mechanisms underpinning miR-210 action. Particular attention will be dedicated to experimentally validated miR-210 direct targets involved in cellular processes related to angiogenesis and diabetes mellitus, such as mitochondrial metabolism, redox balance, apoptosis, migration, and adhesion. Antioxid. Redox Signal. 36, 685-706.

AMPK-regulated miRNA-210-3p is activated during ischaemic neuronal injury and modulates PI3K-p70S6K signalling

Progressive neuronal injury following ischaemic stroke is associated with glutamate-induced depolarization, energetic stress and activation of AMP-activated protein kinase (AMPK). We here identify a molecular signature associated with neuronal AMPK activation, as a critical regulator of cellular response to energetic stress following ischaemia. We report a robust induction of microRNA miR-210-3p both in vitro in primary cortical neurons in response to acute AMPK activation and following ischaemic stroke in vivo. Bioinformatics and reverse phase protein array analysis of neuronal protein expression changes in vivo following administration of a miR-210-3p mimic revealed altered expression of phosphatase and tensin homolog (PTEN), 3-phosphoinositide-dependent protein kinase 1 (PDK1), ribosomal protein S6 kinase (p70S6K) and ribosomal protein S6 (RPS6) signalling in response to increasing miR-210-3p. In vivo, we observed a corresponding reduction in p70S6K activity following ischaemic stroke. Utilizing models of glutamate receptor over-activation in primary neurons, we demonstrated that induction of miR-210-3p was accompanied by sustained suppression of p70S6K activity and that this effect was reversed by miR-210-3p inhibition. Collectively, these results provide new molecular insight into the regulation of cell signalling during ischaemic injury, and suggest a novel mechanism whereby AMPK regulates miR-210-3p to control p70S6K activity in ischaemic stroke and excitotoxic injury.

The impact of proangiogenic microRNA modulation on blood flow recovery following hind limb ischemia. A systematic review and meta-analysis of animal studies

BACKGROUND

Pro-angiogenic microRNA modulation is a potentially attractive approach in the management of peripheral artery disease (PAD). The aim of this systematic review and meta-analysis was to examine the impact of microRNAs involved in the process of angiogenesis on blood flow recovery following hind limb ischemia induction in animal models.

METHODS

A literature search was performed to identify studies testing the efficacy of microRNA treatment on animal models of hind limb ischemia. Following that, a meta-analysis of the included studies was executed with the primary outcome being the change in ischemic-to-normal hind limb perfusion ratio assessed via laser Doppler imaging. Moreover, risk of bias, sensitivity analysis and publication bias were evaluated.

RESULTS

Studies evaluation led to the inclusion of 18 studies whose meta-analysis suggested that microRNA treatment resulted in improved ischemic hind limb perfusion 7 [standardized mean difference (SMD): 0.93, 95% CI 0.49-1.38], 14 (SMD: 1.31, 95% CI 0.78-1.84), and 21 days (SMD: 1.13, 95% CI 0.59-1.66) after hind limb ischemia induction. Moderate-to-substantial heterogeneity and possible publication bias were noted. Risk of bias was unclear despite the balanced baseline animal characteristics.

CONCLUSION

The present meta-analysis suggests that pro-angiogenic modulation of microRNAs accelerates vascular perfusion recovery in animal models of acute hind limb ischemia. Further studies on animal models with similar characteristics to that of PAD patients are warranted to translate those findings in human PAD setting.

Repulsive Guidance Molecule-a and Central Nervous System Diseases

Repulsive guidance molecule-a (RGMa) is a member of glycosylphosphatidylinositol- (GPI-) anchored protein family, which has axon guidance function and is widely involved in the development and pathological processes of the central nervous system (CNS). On the one hand, the binding of RGMa and its receptor Neogenin can regulate axonal guidance, differentiation of neural stem cells into neurons, and the survival of these cells; on the other hand, RGMa can inhibit functional recovery of CNS by inhibiting axonal growth. A number of studies have shown that RGMa may be involved in the pathogenesis of CNS diseases, such as multiple sclerosis, neuromyelitis optica spectrum diseases, cerebral infarction, spinal cord injury, Parkinson's disease, and epilepsy. Targeting RGMa can enhance the functional recovery of CNS, so it may become a promising target for the treatment of CNS diseases. This article will comprehensively review the research progression of RGMa in various CNS diseases up to date.

Mesenchymal stem cell‑derived extracellular vesicles prevent neural stem cell hypoxia injury via promoting miR‑210‑3p expression

Neural stem cells (NSCs) have the potential to give rise to offspring cells and hypoxic injury can impair the function of NSCs. The present study investigated the effects of mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) on NSC injury, as well as the underlying mechanisms. MSC-EVs were isolated and identified via morphological and particle size analysis. Cobalt chloride was used to establish a hypoxic injury model in NSCs. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay was conducted to detect apoptosis. Reverse transcription-quantitative PCR was performed to detect the expression levels of miR-210-3p, and western blotting was used to detect the expression levels of apoptosis-inducing factor (AIF) and Bcl-2 19 kDa interacting protein (BNIP3). Compared with the control group, NSC apoptosis, and the expression of miR-210-3p, AIF and BNIP3 were significantly higher in the cobalt chloride-induced hypoxia group. By contrast, treatment with MSC-EVs further increased miR-210-3p expression levels, but reduced NSC apoptosis and the expression levels of AIF and BNIP3 compared with the model group (P<0.05). In addition, miR-210-3p inhibitor reduced miR-210-3p expression, but promoted hypoxia-induced apoptosis and the expression levels of AIF and BNIP3 compared with the model group (P<0.05). Collectively, the results suggested that MSC-EVs prevented NSC hypoxia injury by promoting miR-210-3p expression, which might reduce AIF and BNIP3 expression levels and NSC apoptosis.

Circulating microRNAs differentiate Kawasaki Disease from infectious febrile illnesses in childhood

BACKGROUND

Kawasaki Disease (KD) is an acute vasculitis of unknown etiology in children that can lead to coronary artery lesions (CAL) in 25% of untreated patients. There is currently no diagnostic test for KD, and the clinical presentation is often difficult to differentiate from other febrile childhood illnesses. Circulating microRNAs (miRNAs) are small noncoding RNA molecules that control gene expression by inducing transcript degradation or by blocking translation. We hypothesize that the expression of circulating miRNAs will differentiate KD from non-KD febrile illnesses in children.

METHODS

Circulating miRNA profiles from 84 KD patients and 29 non-KD febrile controls (7 viral and 22 bacterial infections) were evaluated. 3 ul of serum from each subject was submitted to 3 freeze/heat cycles to ensure miRNA release from microvesicles or interaction with serum proteins. miRNAs were reverse transcribed using a pool of primers specific for each miRNA. Real-time PCR reactions were performed in a 384 well plate containing sequence-specific primers and TaqMan probes in the ABI7900. '.

RESULTS

KD patients (3.6 ± 2.2 yrs., 58% male) were found to have a unique circulating miRNA profile, including upregulation of miRNA-210-3p, -184, and -19a-3p (p < .0001), compared to non-KD febrile controls (8.5 ± 6.1 yrs., 72% male).

CONCLUSIONS

Circulating miRNAs can differentiate KD from infectious febrile childhood diseases, supporting their potential as a diagnostic biomarker for KD.

Expression of miR-210 in the peripheral blood of patients with newly diagnosed type 2 diabetes mellitus and its effect on the number and function of endothelial progenitor cells

OBJECTIVE

This study aims to investigate the correlation between the expression of miR-210 in peripheral blood and the number of peripheral endothelial progenitor cells (EPCs) in patients with type 2 diabetes mellitus (T2DM). We also determined the effect of miR-210 on EPC proliferation, adhesion, migration, tube formation, and apoptosis.

METHODS

A total of 32 patients with newly diagnosed T2DM (T2DM group) and 32 control subjects with normal glucose tolerance (NC group) were included. Peripheral blood samples were collected from each subject. The miR-210 level was determined by quantitative real-time polymerase chain reaction (qRT-PCR), and the number of positive EPCs indicated by CD34, CD133, and KDR expressions was detected by flow cytometry. After isolation, culture, and identification by fluorescent staining, EPCs were divided into four groups: NC group, untransfected type 2 diabetic group, miR-210 inhibitor NC group, and miR-210 inhibitor group. The expression of miR-120 in each group was detected by qRT-PCR, and the changes in the proliferation, adhesion, migration, tube formation, and apoptosis of EPCs after transfection with a miR-210 inhibitor were observed.

RESULTS

The expression level of miR-210 in the T2DM group (5.83 ± 1.26) was significantly higher than that in the NC group (1.18 ± 0.54) (t = 17.26, P < 0.001). The number of EPCs was significantly lower in the T2DM group (39.3 ± 12.6)/10⁶ cells than that in the NC group (76.2 ± 10.7)/10⁶ cells (t = 10.49, P < 0.001). Spearman's correlation analysis showed that the expression of miR-210 in the peripheral blood of patients with T2DM was negatively correlated with the number of EPCs (r = -0.558, P = 0.001). Multiple linear stepwise regression analysis showed that the peripheral blood level of miR-210 was an independent correlation factor that affected the number of EPCs (P < 0.001). After transfection with the miR-210 inhibitor, the proliferation, adhesion, tube formation, and migration levels of EPCs in miR-210 inhibitor group were higher than those in untransfected type 2 diabetic group and miR-210 inhibitor NC group, whereas the apoptosis rate was lower than that in these groups, and these results were statistically significant (P < 0.05).

CONCLUSION

The increased expression of miR-210 in patients with T2DM may be related to the decreased number and function of EPCs in peripheral blood.

Non-Mitogenic Fibroblast Growth Factor 1 Enhanced Angiogenesis Following Ischemic Stroke by Regulating the Sphingosine-1-Phosphate 1 Pathway

Ischemic strokes account for about 80% of all strokes and are associated with a high risk of mortality. Angiogenesis of brain microvascular endothelial cells may contribute to functional restoration following ischemia. Fibroblast growth factor 1 (FGF1), a member of FGF superfamily, involved in embryonic development, angiogenesis, wound healing, and neuron survival. However, the mitogenic activity of FGF1 is known to contribute to several human pathologies, thereby questioning the safety of its clinical applications. Here, we explored the effects and mechanism of action of non-mitogenic FGF1 (nmFGF1) on angiogenesis in mice after ischemia stroke and an oxygen-glucose deprivation (OGD)-induced human brain microvascular endothelial cells (HBMECs) injury model. We found that intranasal administration nmFGF1 significantly promoted angiogenesis in mice after stroke, and significantly increased the formation of matrigel tube and promoted scratch migration in a dose-dependent manner in OGD-induced HBMECs in vitro. However, the co-administration of an FGF receptor 1 (FGFR1)-specific inhibitor PD173074 significantly reversed the effects of nmFGF1 in vitro, suggesting that nmFGF1 functions via FGFR1 activation. Moreover, nmFGF1 activated sphingosine-1-phosphate receptor 1 (S1PR1, S1P1) in mice after stroke in vivo. S1P1 protein antagonist VPC23019 and agonist FTY720 were used to confirm that nmFGF1 promotes angiogenesis in vitro partially through the S1P1 pathway. OGD induced downregulation of S1P1 expression. The S1P1 antagonist VPC23019 blocked the stimulatory effects of nmFGF1, whereas the S1P1 agonist FTY720 exerted effects comparable with those of nmFGF1. Furthermore, PD173074 reversed the effect of nmFGF1 on upregulating S1P1 signaling. In conclusion, nmFGF1 enhanced angiogenesis in mice following stroke and OGD-induced HBMECs through S1P1 pathway regulation mediated via FGFR1 activation. This new discovery suggests the potential therapeutic role of nmFGF1 for the treatment of ischemic strokes.

Impaired Vps34 complex activity-mediated autophagy inhibition contributes to endothelial progenitor cells damage in the ischemic conditions

AIMS

Endothelial progenitor cells (EPCs) are widely accepted to be applied in ischemic diseases. However, the therapeutic potency is largely impeded because of its inviability in these ischemic conditions. Autophagy is recognized to be vital in cell activity. Therefore, we explore the role and the mechanism of autophagy in ischemic EPCs.

METHODS AND RESULTS

We applied 7d-cultured bone marrow EPCs to investigate the autophagy status under the oxygen and glucose deprivation (OGD) conditions in vitro, mimicking the in-vivo harsh ischemia and anoxia microenvironment. We found increased EPC apoptosis, accompanied by an impaired autophagy activation. Intriguingly, mTOR inhibitor Rapamycin was incapable to reverse this damped autophagy and EPC damage. We further found that autophagy pathway downstream Vps34-Beclin1-Atg14 complex assembly and activity were impaired in OGD conditions, and an autophagy-inducing peptide Tat-Beclin1 largely recovered the impaired complex activity and attenuated OGD-stimulated EPC injury through restoring autophagy activation.

CONCLUSIONS

The present study discovered that autophagy activation is inhibited when EPCs located in the ischemia and anoxia conditions. Restoration of Vps34 complex activity obtains sufficient autophagy, thus promoting EPC survival, which will provide a potential target and advance our understanding of autophagy manipulation in stem cell transplantation.