Macrophage miR-210 induction and metabolic reprogramming in response to pathogen interaction boost life-threatening inflammation

miR-210 overexpression increases pressure overload-induced cardiac fibrosis

Aortic stenosis, a common valvular heart disease, can lead to left ventricular pressure overload, triggering pro-fibrotic responses in the heart. miR-210 is a microRNA that responds to hypoxia and ischemia and plays a role in immune regulation and in cardiac remodeling upon myocardial infarction. This study investigated the effects of miR-210 on cardiac fibrosis caused by pressure overload. Using a mouse model with inducible miR-210 over-expression, we subjected mice to transverse aortic constriction (TAC) to induce pressure overload. Mice with miR-210 over-expression developed eccentric hypertrophy, heightened expression of hypertrophic markers (Nppa and Nppb) and increased cross sectional area of cardiomyocytes, impacting the free wall of the left ventricle. These findings suggest that miR-210 worsens cardiac dysfunction. Furthermore, miR-210 over-expression led to a more robust and sustained inflammatory response in the heart, increased interstitial and perivascular fibrosis, and activation of myofibroblasts. miR-210 also promoted angiogenesis. In vitro, cardiac fibroblasts over-expressing miR-210 showed increased adhesion, wound healing and migration capacity. Our results demonstrate that miR-210 contributes to adverse cardiac remodeling in response to pressure overload, including eccentric hypertrophy, inflammation, and fibrosis.

Polyphyllin Ⅵ modulates macrophage polarization through autophagy-NLRP3 inflammasome to alleviate inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract with a rising global prevalence. If left untreated, it can result in severe complications, including colon cancer. Key factors in IBD pathogenesis include macrophages, NOD-like receptor thermal protein domain associated protein 3 (NLRP3), and autophagy. Polyphyllin Ⅵ (PPⅥ), a metanoidal saponin derived from the traditional Chinese herb Chonglou, exhibits significant anti-inflammatory and anti-cancer properties, making it a compound of considerable therapeutic interest.

PURPOSE

The present study investigated the relevant mechanism of PPⅥ on protecting IBD from the perspective of NLRP3 as well as macrophage immunomodulation and laid a theoretical foundation for the development of novel IBD therapeutic drugs.

METHODS

The IBD mice were prepared by dextran sodium sulfate, and RAW 264.7 inflammatory cells were established through LPS and ATP stimulation. The indicators of macrophage polarization, NLRP3, and autophagy were detected using Western Blot, RT-qPCR, H&E staining, immunofluorescence, and flow cytometry.

RESULTS

PPⅥ can enhance the inflammatory state of LPS-induced RAW264.7 macrophages, which can reduce weight loss, decrease DAI score, increase colon length, reduce oxidative stress, and decrease intestinal epithelial barrier damage, and thus diminish inflammatory injury in DSS-induced IBD mice. PPⅥ can modify intestinal inflammation and injury by modulating macrophage function. The administration of PPⅥ can maintain the balance between M1-type macrophages and M2-type macrophages while regulating the intestinal macrophage polarization via the NLRP3 inflammasome and autophagy through wildtype mice, cells, and Nlrp3-/- mice.

CONCLUSION

PPⅥ can regulate macrophage polarization through autophagic modulation of NLRP3 inflammasome to promote the repair of intestinal epithelial damage and maintain the integrity of the mucosal barrier, which contributes to the attenuation of inflammatory injury in DSS-induced IBD mice and provides a database for the development of novel clinical drugs.

INNOVATIONS

1. This subject discovered the protective effect of PPⅥ on IBD mice. 2. This subject proved that macrophages have an important role in the intestinal protection of PPⅥ in IBD mice, and PPⅥ can inhibit the polarization of M1-type macrophages and promote the polarization of M2-type macrophages. 3. This subject demonstrated that PPⅥ could regulate macrophage polarization through NLRP3 inflammasome and ameliorate intestinal inflammation in vitro, in vivo, and in Nlrp3-/- mice. 4. This subject confirmed that PPⅥ could regulate macrophage polarization to alleviate inflammatory injury by inhibiting NLRP3 inflammasome through modulating autophagy in vitro, in vivo, and the application of inhibitors. 5. This study explored the developmental value of PPⅥ and laid the theoretical foundation for the development of novel therapeutic drugs as well as therapeutic strategies for IBD.

MIF tautomerase inhibitor TE-11 prevents inflammatory macrophage activation and glycolytic reprogramming while reducing leukocyte migration and improving Crohn's disease-like colitis in male mice

Background & aims

Crohn's disease (CD) is a chronic inflammatory disorder primarily affecting the gastrointestinal tract. Leukocyte recruitment, M1 macrophage polarization and associated metabolic reprogramming are hallmarks of its pathomechanism. Here, we tested TE-11, a potent MIF tautomerase inhibitor (IC50 = 5.63 μmol/dm3) in experimental Crohn's disease in male mice, in leukocyte recruitment and in inflammatory M1 macrophage activation.

Methods

2,4,6-trinitrobenzenesulfonic acid-(TNBS)-induced colitis was utilized as a CD-model in male mice. We performed macroscopic scoring and cytokine measurements. We also analyzed MIF-induced leukocyte migration and evaluated apoptosis. LPS+IFN-γ-induced RAW264.7 cells were applied as a M1 macrophage model. We performed qPCR, ROS and nitrite determinations, ELISA measurements, mitochondrial oxygen consumption rate and extracellular acidification rate determinations.

Results

TE-11 improved mucosal damage, reduced inflammation score and concentration of IL-1β and IL-6 in the colon. It inhibited MIF-induced human blood eosinophil and neutrophil migration and counteracted the anti-apoptotic effect of MIF. In macrophages, MIF inhibition prevented M1 polarization by downregulating HIF-1α gene expression in LPS+IFN-γ-activated cells. Additionally, the molecule reduced mRNA transcription and protein expression of chemokine CCL-2 and cytokine IL-6 while further increasing SOD2 gene transcription and decreased ROS and nitrite production in macrophages. During inflammatory metabolic reprogramming, TE-11 prevented LPS+IFN-γ-induced metabolic shift from OXPHOS to glycolysis. Similarly to anti-inflammatory M2 cells, TE-11 improved mitochondrial energy production by increasing basal respiration, ATP production, coupling efficiency, maximal respiration and spare respiratory capacity.

Conclusion

Comprehensively, TE-11, a MIF tautomerase inhibitor ameliorates CD-like colitis, reduces MIF-induced eosinophil and neutrophil migration and prevents M1 polarization and associated metabolic reprogramming; therefore, it may prove beneficial as a potential drug candidate regarding CD therapy.

Significances of miRNAs for predicting sepsis mortality: a meta-analysis

Background

Sepsis is a life-threatening condition caused by a dysregulated immune response to infection and remains a major cause of mortality in intensive care units (ICUs). Recent studies have identified microRNAs (miRNAs), a class of small RNA molecules, as potential biomarkers for diagnosing and predicting outcomes in sepsis patients. However, the results of these studies have been inconsistent. This meta-analysis aims to comprehensively evaluate the diagnostic and prognostic value of miRNAs in predicting sepsis-related mortality.

Methods

A comprehensive literature search was performed across major databases, including PubMed, Cochrane Library, EMBASE, and CNKI, up to April 7, 2024. Data extraction and meta-analysis were conducted using Meta-disk 1.4 and STATA 15.1, employing both fixed- and random-effects models to ensure robust statistical analysis.

Results

A total of 55 studies met the inclusion criteria and were analyzed. The pooled sensitivity, specificity, and area under the summary receiver operating characteristic (SROC) curve for miRNA detection were calculated. The overall performance of total miRNA detection demonstrated a sensitivity of 0.76 (95% confidence interval [CI]: 0.74-0.77), a specificity of 0.72 (95% CI: 0.71-0.73), and an SROC value of 0.83. Subgroup analyses revealed that miR-133a-3p exhibited the highest diagnostic accuracy, with a pooled sensitivity of 0.83 (95% CI: 0.70-0.92), specificity of 0.79 (95% CI: 0.71-0.86), and an SROC value of 0.90. Additionally, other miRNAs, including miR-146a, miR-21, miR-210, miR-223-3p, miR-155, miR-25, miR-122, miR-125a, miR-125b, and miR-150, also demonstrated high SROC values (0.84 to 0.76).

Conclusion

This meta-analysis underscores the potential of several microRNAs (miRNAs) as reliable biomarkers for predicting sepsis mortality. Specifically, miR-133a-3p, miR-146a, miR-21, miR-210, miR-223-3p, miR-155, miR-25, miR-122, miR-125b, and miR-150 emerge as promising candidates for clinical applications in sepsis prognosis.

A functional single-cell metabolic survey identifies Elovl1 as a target to enhance CD8+ T cell fitness in solid tumours

Reprogramming T cell metabolism can improve intratumoural fitness. By performing a CRISPR/Cas9 metabolic survey in CD8+ T cells, we identified 83 targets and we applied single-cell RNA sequencing to disclose transcriptome changes associated with each metabolic perturbation in the context of pancreatic cancer. This revealed elongation of very long-chain fatty acids protein 1 (Elovl1) as a metabolic target to sustain effector functions and memory phenotypes in CD8+ T cells. Accordingly, Elovl1 inactivation in adoptively transferred T cells combined with anti-PD-1 showed therapeutic efficacy in resistant pancreatic and melanoma tumours. The accumulation of saturated long-chain fatty acids in Elovl1-deficient T cells destabilized INSIG1, leading to SREBP2 activation, increased plasma membrane cholesterol and stronger T cell receptor signalling. Elovl1-deficient T cells increased mitochondrial fitness and fatty acid oxidation, thus withstanding the metabolic stress imposed by the tumour microenvironment. Finally, ELOVL1 in CD8+ T cells correlated with anti-PD-1 response in patients with melanoma. Altogether, Elovl1 targeting synergizes with anti-PD-1 to promote effective T cell responses.

Current state of epigenetics in giant cell arteritis: Focus on microRNA dysregulation

Giant cell arteritis (GCA) is a primary systemic vasculitis affecting the elderly, characterized by a granulomatous vessel wall inflammation of large- and medium-sized arteries. The immunopathology of GCA is complex, involving both the innate and adaptive arms of the immune system, where a maladaptive inflammatory-driven vascular repair process ultimately results in vessel wall thickening, intramural vascular smooth muscle cell proliferation, neovascularization and vessel lumen occlusion, which can lead to serious ischemic complications such as visual loss and ischemic stroke. Over the past decade, microRNA (miRNA) dysregulation has been highlighted as an important contributing factor underlying the pathogenesis of GCA. Since current understanding of miRNA involvement in GCA remains largely based on extrapolation of previously determined miRNA functions in vitro or in loss- or gain-of-function studies, an overall insight into the role of miRNA alteration in GCA pathophysiology remains limited. In this narrative review, we summarize the current knowledge on aberrantly expressed miRNAs in GCA and thoroughly discuss the impact of their altered regulatory role in the context of GCA setting. Furthermore, we address challenges and future perspectives in utilization of miRNA-based diagnostic and prognostic biomarkers of GCA in clinical settings.

Cancer cell-intrinsic biosynthesis of itaconate promotes tumor immunogenicity

The Krebs cycle byproduct itaconate has recently emerged as an important metabolite regulating macrophage immune functions, but its role in tumor cells remains unknown. Here, we show that increased tumor-intrinsic cis-aconitate decarboxylase (ACOD1 or CAD, encoded by immune-responsive gene 1, Irg1) expression and itaconate production promote tumor immunogenicity and anti-tumor immune responses. Furthermore, we identify thimerosal, a vaccine preservative, as a specific inducer of IRG1 expression in tumor cells but not in macrophages, thereby enhancing tumor immunogenicity. Mechanistically, thimerosal induces itaconate production through a ROS-RIPK3-IRF1 signaling axis in tumor cells. Further, increased IRG1/itaconate upregulates antigen presentation-related gene expression via promoting TFEB nuclear translocation. Intratumoral injection of thimerosal induced itaconate production, activated the tumor immune microenvironment, and inhibited tumor growth in a T cell-dependent manner. Importantly, IRG1 deficiency markedly impaired tumor response to thimerosal treatment. Furthermore, itaconate induction by thimerosal potentiates the anti-tumor efficacy of adoptive T-cell therapy and anti-PD1 therapy in a mouse lymphoma model. Hence, our findings identify a new role for tumor intrinsic IRG1/itaconate in promoting tumor immunogenicity and provide a translational means to increase immunotherapy efficacy.

Acid affairs in anti-tumour immunity

Metabolic rewiring of cancer cells is one of the hallmarks of cancer. As a consequence, the metabolic landscape of the tumour microenvironment (TME) differs compared to correspondent healthy tissues. Indeed, due to the accumulation of acid metabolites, such as lactate, the pH of the TME is generally acidic with a pH drop that can be as low as 5.6. Disruptions in the acid-base balance and elevated lactate levels can drive malignant progression not only through cell-intrinsic mechanisms but also by impacting the immune response. Generally, acidity and lactate dampen the anti-tumour response of both innate and adaptive immune cells favouring tumour progression and reducing the response to immunotherapy. In this review, we summarize the current knowledge on the functional, metabolic and epigenetic effects of acidity and lactate on the cells of the immune system. In particular, we focus on the role of monocarboxylate transporters (MCTs) and other solute carrier transporters (SLCs) that, by mediating the exchange of lactate (among other metabolites) and bicarbonate, participate in pH regulation and lactate transport in the cancer context. Finally, we discuss advanced approaches to target pH or lactate in the TME to enhance the anti-tumour immune response.

MicroRNAs are enriched at COVID-19 genomic risk regions, and their blood levels correlate with the COVID-19 prognosis of cancer patients infected by SARS-CoV-2

BACKGROUND

Cancer patients are more susceptible to an aggressive course of COVID-19. Developing biomarkers identifying cancer patients at high risk of COVID-19-related death could help determine who needs early clinical intervention. The miRNAs hosted in the genomic regions associated with the risk of aggressive COVID-19 could represent potential biomarkers for clinical outcomes.

PATIENTS AND METHODS

Plasma samples were collected at The University of Texas MD Anderson Cancer Center from cancer patients (N = 128) affected by COVID-19. Serum samples were collected from vaccinated healthy individuals (n = 23) at the Municipal Clinical Emergency Teaching Hospital in Timisoara, Romania. An in silico positional cloning approach was used to identify the presence of miRNAs at COVID-19 risk-associated genomic regions: CORSAIRs (COvid-19 RiSk AssocIated genomic Regions). The miRNA levels were measured by RT-qPCR.

RESULTS

We found that miRNAs were enriched in CORSAIR. Low plasma levels of hsa-miR-150-5p and hsa-miR-93-5p were associated with higher COVID-19-related death. The levels of hsa-miR-92b-3p were associated with SARS-CoV-2 test positivity. Peripheral blood mononuclear cells (PBMC) increased secretion of hsa-miR-150-5p, hsa-miR-93-5p, and hsa-miR-92b-3p after in vitro TLR7/8- and T cell receptor (TCR)-mediated activation. Increased levels of these three miRNAs were measured in the serum samples of healthy individuals between one and nine months after the second dose of the Pfizer-BioNTech COVID-19 vaccine. SARS-CoV-2 infection of human airway epithelial cells influenced the miRNA levels inside their secreted extracellular vesicles.

CONCLUSIONS

MiRNAs are enriched at CORSAIR. Plasma miRNA levels can represent a potential blood biomarker for predicting COVID-19-related death in cancer patients.

miR-210 is essential to retinal homeostasis in fruit flies and mice

BACKGROUND

miR-210 is one of the most evolutionarily conserved microRNAs. It is known to be involved in several physiological and pathological processes, including response to hypoxia, angiogenesis, cardiovascular diseases and cancer. Recently, new roles of this microRNA are emerging in the context of eye and visual system homeostasis. Recent studies in Drosophila melanogaster unveiled that the absence of miR-210 leads to a progressive retinal degeneration characterized by the accumulation of lipid droplets and disruptions in lipid metabolism. However, the possible conservation of miR-210 knock-out effect in the mammalian retina has yet to be explored.

RESULTS

We further investigated lipid anabolism and catabolism in miR-210 knock-out (KO) flies, uncovering significant alterations in gene expression within these pathways. Additionally, we characterized the retinal morphology of flies overexpressing (OE) miR-210, which was not affected by the increased levels of the microRNA. For the first time, we also characterized the retinal morphology of miR-210 KO and OE mice. Similar to flies, miR-210 OE did not affect retinal homeostasis, whereas miR-210 KO mice exhibited photoreceptor degeneration. To explore other potential parallels between miR-210 KO models in flies and mice, we examined lipid metabolism, circadian behaviour, and retinal transcriptome in mice, but found no similarities. Specifically, RNA-seq confirmed the lack of involvement of lipid metabolism in the mice's pathological phenotype, revealing that the differentially expressed genes were predominantly associated with chloride channel activity and extracellular matrix homeostasis. Simultaneously, transcriptome analysis of miR-210 KO fly brains indicated that the observed alterations extend beyond the eye and may be linked to neuronal deficiencies in signal detection and transduction.

CONCLUSIONS

We provide the first morphological characterization of the retina of miR-210 KO and OE mice, investigating the role of this microRNA in mammalian retinal physiology and exploring potential parallels with phenotypes observed in fly models. Although the lack of similarities in lipid metabolism, circadian behaviour, and retinal transcriptome in mice suggests divergent mechanisms of retinal degeneration between the two species, transcriptome analysis of miR-210 KO fly brains indicates the potential existence of a shared upstream mechanism contributing to retinal degeneration in both flies and mammals.

Nucleotide metabolism in cancer cells fuels a UDP-driven macrophage cross-talk, promoting immunosuppression and immunotherapy resistance

Many individuals with cancer are resistant to immunotherapies. Here, we identify the gene encoding the pyrimidine salvage pathway enzyme cytidine deaminase (CDA) among the top upregulated metabolic genes in several immunotherapy-resistant tumors. We show that CDA in cancer cells contributes to the uridine diphosphate (UDP) pool. Extracellular UDP hijacks immunosuppressive tumor-associated macrophages (TAMs) through its receptor P2Y6. Pharmacologic or genetic inhibition of CDA in cancer cells (or P2Y6 in TAMs) disrupts TAM-mediated immunosuppression, promoting cytotoxic T cell entry and susceptibility to anti-programmed cell death protein 1 (anti-PD-1) treatment in resistant pancreatic ductal adenocarcinoma (PDAC) and melanoma models. Conversely, CDA overexpression in CDA-depleted PDACs or anti-PD-1-responsive colorectal tumors or systemic UDP administration (re)establishes resistance. In individuals with PDAC, high CDA levels in cancer cells correlate with increased TAMs, lower cytotoxic T cells and possibly anti-PD-1 resistance. In a pan-cancer single-cell atlas, CDAhigh cancer cells match with T cell cytotoxicity dysfunction and P2RY6high TAMs. Overall, we suggest CDA and P2Y6 as potential targets for cancer immunotherapy.

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.

The potential immunological mechanisms of sepsis

Sepsis is described as a life-threatening organ dysfunction and a heterogeneous syndrome that is a leading cause of morbidity and mortality in intensive care settings. Severe sepsis could incite an uncontrollable surge of inflammatory cytokines, and the host immune system's immunosuppression could respond to counter excessive inflammatory responses, characterized by the accumulated anti-inflammatory cytokines, impaired function of immune cells, over-proliferation of myeloid-derived suppressor cells and regulatory T cells, depletion of immune effector cells by different means of death, etc. In this review, we delve into the underlying pathological mechanisms of sepsis, emphasizing both the hyperinflammatory phase and the associated immunosuppression. We offer an in-depth exploration of the critical mechanisms underlying sepsis, spanning from individual immune cells to a holistic organ perspective, and further down to the epigenetic and metabolic reprogramming. Furthermore, we outline the strengths of artificial intelligence in analyzing extensive datasets pertaining to septic patients, showcasing how classifiers trained on various clinical data sources can identify distinct sepsis phenotypes and thus to guide personalized therapy strategies for the management of sepsis. Additionally, we provide a comprehensive summary of recent, reliable biomarkers for hyperinflammatory and immunosuppressive states, facilitating more precise and expedited diagnosis of sepsis.

Quercetin ameliorates ulcerative colitis by restoring the balance of M2/M1 and repairing the intestinal barrier via downregulating cGAS‒STING pathway

Macrophage polarization is closely associated with the pathogenesis of ulcerative colitis (UC). Quercetin, a flavonoid, has shown promise as a treatment for inflammatory diseases, but its specific mechanism of action remains unclear. This study investigates whether quercetin can regulate intestinal macrophage polarization and promote intestinal tissue repair via the cGAS-STING pathway for the treatment of UC. In vivo, mice with 3% DSS-induced UC were intraperitoneally injected with quercetin and RU.521 for 7 days, following which their general conditions and corresponding therapeutic effects were assessed. The impact of interferon-stimulated DNA (ISD) and quercetin on macrophage polarization and the cGAS-STING pathway was investigated using RAW264.7 cells and bone marrow-derived macrophages (BMDMs) in vitro. The results demonstrated that ISD induced M1 macrophage polarization and activated the cGAS-STING pathway in vitro, while quercetin reversed ISD's inflammatory effects. In vivo, quercetin suppressed the cGAS-STING pathway in the intestinal macrophages of DSS-induced UC mice, which reduced M1 macrophage polarization, increased M2 polarization, and facilitated intestinal barrier repair in UC. Taken together, these findings provide new insights into the mechanisms via which quercetin could be used to treat UC.

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

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

MicroRNA -21 expression as an auxiliary diagnostic biomarker of acute brucellosis

BACKGROUND

This study aimed to measure the expression levels of peripheral blood miRNAs in brucellosis and their involvement in the different phases of the brucellosis.

METHODS

The expression levels of miRNAs including miR-210, miR-155, miR-150, miR-146a, miR-139-3p, miR-125a-5p, miR-29 and miR-21 were quantified in 57 brucellosis patients subgrouped into acute, under treatment & relapse phase and 30 healthy controls (HCs) using real-time polymerase chain reaction (RT-PCR). The receiver operating characteristic (ROC) analysis curve analysis was performed to find a biomarker for discrimination of different phases of brucellosis.

RESULTS

The expression of miR-155, miR-146a, miR-125a-5p, miR-29, and miR-21 was found to be elevated in the acute brucellosis patients compared to HCs. miR-29 changed in under-treatment patients, while miR-139-3p and miR-125a-5p showed alterations in relapse cases. The ROC curve analysis depicted the potential involvement of miR-21 in the pathogenesis of acute brucellosis.

CONCLUSION

The expression level of miR-21 is significantly augmented in acute brucellosis and has the potential to be a contributing diagnostic factor for acute infection.

MicroRNAs Associated with a Bad Prognosis in Acute Myeloid Leukemia and Their Impact on Macrophage Polarization

MicroRNAs (miRNAs) are short, non-coding ribonucleic acids (RNAs) associated with gene expression regulation. Since the discovery of the first miRNA in 1993, thousands of miRNAs have been studied and they have been associated not only with physiological processes, but also with various diseases such as cancer and inflammatory conditions. MiRNAs have proven to be not only significant biomarkers but also an interesting therapeutic target in various diseases, including cancer. In acute myeloid leukemia (AML), miRNAs have been regarded as a welcome addition to the limited therapeutic armamentarium, and there is a vast amount of data on miRNAs and their dysregulation. Macrophages are innate immune cells, present in various tissues involved in both tissue repair and phagocytosis. Based on their polarization, macrophages can be classified into two groups: M1 macrophages with pro-inflammatory functions and M2 macrophages with an anti-inflammatory action. In cancer, M2 macrophages are associated with tumor evasion, metastasis, and a poor outcome. Several miRNAs have been associated with a poor prognosis in AML and with either the M1 or M2 macrophage phenotype. In the present paper, we review miRNAs with a reported negative prognostic significance in cancer with a focus on AML and analyze their potential impact on macrophage polarization.

Pyruvate dehydrogenase kinase regulates macrophage polarization in metabolic and inflammatory diseases

Macrophages are highly heterogeneous and plastic, and have two main polarized phenotypes that are determined by their microenvironment, namely pro- and anti-inflammatory macrophages. Activation of pro-inflammatory macrophages is closely associated with metabolic reprogramming, especially that of aerobic glycolysis. Mitochondrial pyruvate dehydrogenase kinase (PDK) negatively regulates pyruvate dehydrogenase complex activity through reversible phosphorylation and further links glycolysis to the tricarboxylic acid cycle and ATP production. PDK is commonly associated with the metabolism and polarization of macrophages in metabolic and inflammatory diseases. This review examines the relationship between PDK and macrophage metabolism and discusses the mechanisms by which PDK regulates macrophage polarization, migration, and inflammatory cytokine secretion in metabolic and inflammatory diseases. Elucidating the relationships between the metabolism and polarization of macrophages under physiological and pathological conditions, as well as the regulatory pathways involved, may provide valuable insights into the etiology and treatment of macrophage-mediated inflammatory diseases.

A Machine Learning Model Based on microRNAs for the Diagnosis of Essential Hypertension

INTRODUCTION

Hypertension is a major and modifiable risk factor for cardiovascular diseases. Essential, primary, or idiopathic hypertension accounts for 90-95% of all cases. Identifying novel biomarkers specific to essential hypertension may help in understanding pathophysiological pathways and developing personalized treatments. We tested whether the integration of circulating microRNAs (miRNAs) and clinical risk factors via machine learning modeling may provide useful information and novel tools for essential hypertension diagnosis and management.

MATERIALS AND METHODS

In total, 174 participants were enrolled in the present observational case-control study, among which, there were 89 patients with essential hypertension and 85 controls. A discovery phase was conducted using small RNA sequencing in whole blood samples obtained from age- and sex-matched hypertension patients (n = 30) and controls (n = 30). A validation phase using RT-qPCR involved the remaining 114 participants. For machine learning, 170 participants with complete data were used to generate and evaluate the classification model.

RESULTS

Small RNA sequencing identified seven miRNAs downregulated in hypertensive patients as compared with controls in the discovery group, of which six were confirmed with RT-qPCR. In the validation group, miR-210-3p/361-3p/362-5p/378a-5p/501-5p were also downregulated in hypertensive patients. A machine learning support vector machine (SVM) model including clinical risk factors (sex, BMI, alcohol use, current smoker, and hypertension family history), miR-361-3p, and miR-501-5p was able to classify hypertension patients in a test dataset with an AUC of 0.90, a balanced accuracy of 0.87, a sensitivity of 0.83, and a specificity of 0.91. While five miRNAs exhibited substantial downregulation in hypertension patients, only miR-361-3p and miR-501-5p, alongside clinical risk factors, were consistently chosen in at least eight out of ten sub-training sets within the SVM model.

CONCLUSIONS

This study highlights the potential significance of miRNA-based biomarkers in deepening our understanding of hypertension's pathophysiology and in personalizing treatment strategies. The strong performance of the SVM model highlights its potential as a valuable asset for diagnosing and managing essential hypertension. The model remains to be extensively validated in independent patient cohorts before evaluating its added value in a clinical setting.

Analysis of lactate metabolism-related genes and their association with immune infiltration in septic shock via bioinformatics method

Background: Lactate, as an essential clinical evaluation index of septic shock, is crucial in the incidence and progression of septic shock. This study aims to investigate the differential expression, regulatory relationship, clinical diagnostic efficacy, and immune infiltration of lactate metabolism-related genes (LMGs) in septic shock. Methods: Two sepsis shock datasets (GSE26440 and GSE131761) were screened from the GEO database, and the common differentially expressed genes (DEGs) of the two datasets were screened out. LMGs were selected from the GeneCards database, and lactate metabolism-related DEGs (LMDEGs) were determined by integrating DEGs and LMGs. Protein-protein interaction networks, mRNA-miRNA, mRNA-RBP, and mRNA-TF interaction networks were constructed using STRING, miRDB, ENCORI, and CHIPBase databases, respectively. Receiver operating characteristic (ROC) curves were constructed for each of the LMDEGs to evaluate the diagnostic efficacy of the expression changes in relation to septic shock. Finally, immune infiltration analysis was performed using ssGSEA and CIBERSORT. Results: This study identified 10 LMDEGs, including LDHB, STAT3, LDHA, GSR, FOXM1, PDP1, GCDH, GCKR, ABCC1, and CDKN3. Enrichment analysis revealed that DEGs were significantly enriched in pathways such as pyruvate metabolism, hypoxia pathway, and immune-inflammatory pathways. PPI networks based on LMDEGs, as well as 148 pairs of mRNA-miRNA interactions, 243 pairs of mRNA-RBP interactions, and 119 pairs of mRNA-TF interactions were established. ROC curves of eight LMDEGs (LDHA, GSR, STAT3, CDKN3, FOXM1, GCKR, PDP1, and LDHB) with consistent expression patterns in two datasets had an area under the curve (AUC) ranging from 0.662 to 0.889. The results of ssGSEA and CIBERSORT both showed significant differences in the infiltration of various immune cells, including CD8 T cells, T regulatory cells, and natural killer cells, and LMDEGs such as STAT3, LDHB, LDHA, PDP1, GSR, FOXM1, and CDKN3 were significantly associated with various immune cells. Conclusion: The LMDEGs are significantly associated with the immune-inflammatory response in septic shock and have a certain diagnostic accuracy for septic shock.

miRNA, lncRNA and circRNA: targeted molecules with therapeutic promises in Mycoplasma pneumoniae infection

Mycoplasma pneumoniae (MP) is primarily recognized as a respiratory pathogen that causes community-acquired pneumonia, which can lead to acute upper and lower airway inflammation and extrapulmonary syndrome. Refractory pneumonia caused by MP can cause severe complications and even be life-threatening, particularly in infants and the elderly. It is well-known that non-coding RNAs (ncRNAs) represented by miRNAs, lncRNAs and circRNAs have been manifested to be widely involved in the regulation of gene expression. Growing evidence indicates that these ncRNAs have distinct differentiated expression in MP infection and affect multiple biological processes, playing an indispensable role in the initiation and promotion of MP infection. However, the epigenetic mechanisms involved in the development of MP infection remain unclear. This article reviews the mechanisms by which miRNAs, lncRNAs, and circRNAs mediate MP infection, such as inflammatory responses, apoptosis and pulmonary fibrosis. Focusing on miRNAs, lncRNAs and circRNAs associated with MP infection could provide new insights into this disease's early diagnosis and therapeutic approaches.

miR-210 promotes hepatocellular carcinoma progression by modulating macrophage autophagy through PI3K/AKT/mTOR signaling

BACKGROUND

Tumor-associated macrophages (TAMs) play an important role in tumor development. Increasing research suggests that miR-210 may promote the progression of tumor virulence, but whether its pro-carcinogenic effect in primary hepatocellular carcinoma (HCC) is via an action on M2 macrophages has not been examined.

METHODS

Differentiation of THP-1 monocytes into M2-polarized macrophages was induced with phorbol myristate acetate (PMA) and IL-4, IL-13. M2 macrophages were transfected with miR-210 mimics or miR-210 inhibitors. Flow cytometry was used to identify macrophage-related markers and apoptosis levels. The autophagy level of M2 macrophages, expression of PI3K/AKT/mTOR signaling pathway-related mRNAs and protein were detected by qRT-PCR and Western blot. HepG2 and MHCC-97H HCC cell lines were cultured with M2 macrophages conditioned medium to explore the effects of M2 macrophage-derived miR-210 on the proliferation, migration, invasion and apoptosis of HCC cells.

RESULTS

qRT-PCR showed increased expression of miR-210 in M2 macrophages. Autophagy-related gene and protein expression was enhanced in M2 macrophages transfected with miR-210 mimics, while apoptosis-related proteins were decreased. MDC staining and transmission electron microscopy observed the accumulation of MDC-labeled vesicles and autophagosomes in M2 macrophages in the miR-210 mimic group. The expression of PI3K/AKT/mTOR signaling pathway in M2 macrophages was reduced in miR-210 mimic group. HCC cells co-cultured with M2 macrophages transfected with miR-210 mimics exhibited enhanced proliferation and invasive ability as compared to the control group, while apoptosis levels were reduced. Moreover, promoting or inhibiting autophagy could enhance or abolish the above observed biological effects, respectively.

CONCLUSIONS

miR-210 can promote autophagy of M2 macrophages via PI3K/AKT/mTOR signaling pathway. M2 macrophage-derived miR-210 promotes the malignant progression of HCC via autophagy, suggesting that macrophage autophagy may serve as a new therapeutic target for HCC, and targeting miR-210 may reset the effect of M2 macrophages on HCC.

Comparative microRNA profiling of Trypanosoma cruzi infected human cells

Introduction

Trypanosoma cruzi, the causative agent of Chagas disease, can infect almost any nucleated cell in the mammalian host. Although previous studies have described the transcriptomic changes that occur in host cells during parasite infection, the understanding of the role of post-transcriptional regulation in this process is limited. MicroRNAs, a class of short non-coding RNAs, are key players in regulating gene expression at the post-transcriptional level, and their involvement in the host-T. cruzi interplay is a growing area of research. However, to our knowledge, there are no comparative studies on the microRNA changes that occur in different cell types in response to T. cruzi infection.

Methods and results

Here we investigated microRNA changes in epithelial cells, cardiomyocytes and macrophages infected with T. cruzi for 24 hours, using small RNA sequencing followed by careful bioinformatics analysis. We show that, although microRNAs are highly cell type-specific, a signature of three microRNAs -miR-146a, miR-708 and miR-1246, emerges as consistently responsive to T. cruzi infection across representative human cell types. T. cruzi lacks canonical microRNA-induced silencing mechanisms and we confirm that it does not produce any small RNA that mimics known host microRNAs. We found that macrophages show a broad response to parasite infection, while microRNA changes in epithelial and cardiomyocytes are modest. Complementary data indicated that cardiomyocyte response may be greater at early time points of infection.

Conclusions

Our findings emphasize the significance of considering microRNA changes at the cellular level and complement previous studies conducted at higher organizational levels, such as heart samples. While miR-146a has been previously implicated in T. cruzi infection, similarly to its involvement in many other immunological responses, miR-1246 and miR-708 are demonstrated here for the first time. Given their expression in multiple cell types, we anticipate our work as a starting point for future investigations into their role in the post-transcriptional regulation of T. cruzi infected cells and their potential as biomarkers for Chagas disease.

Role of MicroRNAs in Regulation of Cellular Response to Hypoxia

Hypoxia causes changes in transcription of the genes that contribute to adaptation of the cells to low levels of oxygen. The main mechanism regulating cellular response to hypoxia is activation of hypoxia-inducible transcription factors (HIF), which include several isoforms and control expression of more than a thousand genes. HIF activity is regulated at various levels, including by small non-coding RNA molecules called microRNAs (miRNAs). miRNAs regulate cellular response to hypoxia by influencing activation of HIF, its degradation, and translation of HIF-dependent proteins. At the same time, HIFs also affect miRNAs biogenesis. Data on the relationship of a particular HIF isoform with miRNAs are contradictory, since studies have been performed using different cell lines, various types of experimental animals and clinical material, as well as at different oxygen concentrations and durations of hypoxic exposure. In addition, HIF expression may be affected by the initial resistance of organisms to lack of oxygen, which has not been taken into account in the studies. This review analyzes the data on the effect of hypoxia on biogenesis and functioning of miRNAs, as well as on the effect of miRNAs on mRNAs of the genes involved in adaptation to oxygen deficiency. Understanding the mechanisms of relationship between HIF, hypoxia, and miRNA is necessary to develop new approaches to personalized therapy for diseases accompanied by oxygen deficiency.

Roles of macrophages on ulcerative colitis and colitis-associated colorectal cancer

Colitis-associated colorectal cancer is the most serious complication of ulcerative colitis. Long-term chronic inflammation increases the incidence of CAC in UC patients. Compared with sporadic colorectal cancer, CAC means multiple lesions, worse pathological type and worse prognosis. Macrophage is a kind of innate immune cell, which play an important role both in inflammatory response and tumor immunity. Macrophages are polarized into two phenotypes under different conditions: M1 and M2. In UC, enhanced macrophage infiltration produces a large number of inflammatory cytokines, which promote tumorigenesis of UC. M1 polarization has an anti-tumor effect after CAC formation, whereas M2 polarization promotes tumor growth. M2 polarization plays a tumor-promoting role. Some drugs have been shown to that prevent and treat CAC effectively by targeting macrophages.

MicroRNA-210 Downregulates TET2 (Ten-Eleven Translocation Methylcytosine Dioxygenase 2) and Contributes to Neuroinflammation in Ischemic Stroke of Adult Mice

BACKGROUND

Stroke is a leading cause of morbidity and mortality worldwide. Neuroinflammation plays a key role in acute brain injury of ischemic stroke. MicroRNA-210 (miR210) is the master hypoxamir and regulates microglial activation and inflammation in a variety of diseases. In this study, we uncovered the mechanism of miR210 in orchestrating ischemic stroke-induced neuroinflammation through repression of TET2 (ten-eleven translocation methylcytosine dioxygenase 2) in the adult mouse brain.

METHODS

Ischemic stroke was induced in adult WT (wild type) or miR210 KO (miR210 deficient) mice by transient intraluminal middle cerebral artery occlusion. Injection of TET2 silencing RNA or miR210 complementary locked nucleic acid oligonucleotides, or miR210 KO mice were used to validate miR210-TET2 axis and its role in ischemic brain injury. Furthermore, the effect of TET2 overexpression on miR210-stimulated proinflammatory cytokines was examined in BV2 microglia. Post assays included magnetic resonance imaging scan for brain infarct size; neurobehavioral tests, reverse transcription-quantitative polymerase chain reaction, and Western blot for miR210; and TET2 levels, flow cytometry, and ELISA for neuroinflammation in the brain after stroke or microglia in vitro.

RESULTS

miR210 injection significantly reduced TET2 protein abundance in the brain, while miR210 complementary locked nucleic acid oligonucleotides or miR210 KO preserved TET2 regardless of ischemic brain injury. TET2 knockdown reversed the protective effects of miR210 inhibition or miR210 KO on ischemic stroke-induced brain infarct size and neurobehavioral deficits. Moreover, flow cytometry and ELISA assays showed that TET2 knockdown also significantly dampened the anti-inflammatory effect of miR210 inhibition on microglial activation and IL (interleukin)-6 release after stroke. In addition, overexpression of TET2 in BV2 microglia counteracted miR210-induced increase in cytokines.

CONCLUSIONS

miR210 inhibition reduced ischemic stroke-induced neuroinflammatory response via repression of TET2 in the adult mouse brain, suggesting that miR210 is a potential treatment target for acute brain injury after ischemic stroke.

Obstructive Sleep Apnea-induced Endothelial Dysfunction Is Mediated by miR-210

Rationale: Obstructive sleep apnea (OSA)-induced endothelial cell (EC) dysfunction contributes to OSA-related cardiovascular sequelae. The mechanistic basis of endothelial impairment by OSA is unclear. Objectives: The goals of this study were to identify the mechanism of OSA-induced EC dysfunction and explore the potential therapies for OSA-accelerated cardiovascular disease. Methods: The experimental methods include data mining, bioinformatics, EC functional analyses, OSA mouse models, and assessment of OSA human subjects. Measurements and Main Results: Using mined microRNA sequencing data, we found that microRNA 210 (miR-210) conferred the greatest induction by intermittent hypoxia in ECs. Consistently, the serum concentration of miR-210 was higher in individuals with OSA from two independent cohorts. Importantly, miR-210 concentration was positively correlated with the apnea-hypopnea index. RNA sequencing data collected from ECs transfected with miR-210 or treated with OSA serum showed a set of genes commonly altered by miR-210 and OSA serum, which are largely involved in mitochondrion-related pathways. ECs transfected with miR-210 or treated with OSA serum showed reduced [Formula: see text]o2 rate, mitochondrial membrane potential, and DNA abundance. Mechanistically, intermittent hypoxia-induced SREBP2 (sterol regulatory element-binding protein 2) bound to the promoter region of miR-210, which in turn inhibited the iron-sulfur cluster assembly enzyme and led to mitochondrial dysfunction. Moreover, the SREBP2 inhibitor betulin alleviated intermittent hypoxia-increased systolic blood pressure in the OSA mouse model. Conclusions: These results identify an axis involving SREBP2, miR-210, and mitochondrial dysfunction, representing a new mechanistic link between OSA and EC dysfunction that may have important implications for treating and preventing OSA-related cardiovascular sequelae.

Targeting the bicarbonate transporter SLC4A4 overcomes immunosuppression and immunotherapy resistance in pancreatic cancer

Solid tumors are generally characterized by an acidic tumor microenvironment (TME) that favors cancer progression, therapy resistance and immune evasion. By single-cell RNA-sequencing analysis in individuals with pancreatic ductal adenocarcinoma (PDAC), we reveal solute carrier family 4 member 4 (SLC4A4) as the most abundant bicarbonate transporter, predominantly expressed by epithelial ductal cells. Functionally, SLC4A4 inhibition in PDAC cancer cells mitigates the acidosis of the TME due to bicarbonate accumulation in the extracellular space and a decrease in lactate production by cancer cells as the result of reduced glycolysis. In PDAC-bearing mice, genetic or pharmacological SLC4A4 targeting improves T cell-mediated immune response and breaches macrophage-mediated immunosuppression, thus inhibiting tumor growth and metastases. In addition, Slc4a4 targeting in combination with immune checkpoint blockade is able to overcome immunotherapy resistance and prolong survival. Overall, our data propose SLC4A4 as a therapeutic target to unleash an antitumor immune response in PDAC.

Mitochondrial citrate accumulation drives alveolar epithelial cell necroptosis in lipopolysaccharide-induced acute lung injury

Necroptosis is the major cause of death in alveolar epithelial cells (AECs) during acute lung injury (ALI). Here, we report a previously unrecognized mechanism for necroptosis. We found an accumulation of mitochondrial citrate (citrate^mt) in lipopolysaccharide (LPS)-treated AECs because of the downregulation of Idh3α and citrate carrier (CIC, also known as Slc25a1). shRNA- or inhibitor-mediated inhibition of Idh3α and Slc25a1 induced citrate^mt accumulation and necroptosis in vitro. Mice with AEC-specific Idh3α and Slc25a1 deficiency exhibited exacerbated lung injury and AEC necroptosis. Interestingly, the overexpression of Idh3α and Slc25a1 decreased citrate^mt levels and rescued AECs from necroptosis. Mechanistically, citrate^mt accumulation induced mitochondrial fission and excessive mitophagy in AECs. Furthermore, citrate^mt directly interacted with FUN14 domain-containing protein 1 (FUNDC1) and promoted the interaction of FUNDC1 with dynamin-related protein 1 (DRP1), leading to excessive mitophagy-mediated necroptosis and thereby initiating and promoting ALI. Importantly, necroptosis induced by citrate^mt accumulation was inhibited in FUNDC1-knockout AECs. We show that citrate^mt accumulation is a novel target for protection against ALI involving necroptosis.

Small extracellular vesicles derived from hypoxic preconditioned dental pulp stem cells ameliorate inflammatory osteolysis by modulating macrophage polarization and osteoclastogenesis

Extensive macrophage inflammatory responses and osteoclast formation are predominant during inflammatory or infective osteolysis. Mesenchymal stem cell (MSC)-derived small extracellular vesicles (MSC-sEV) have been shown to exert therapeutic effects on bone defects. However, cultured MSCs are typically exposed to normoxia (21% O₂) in vitro, which differs largely from the oxygen concentration in vivo under hypoxic conditions. It is largely unknown whether sEV derived from dental pulp stem cells (DPSCs) cultured under hypoxic conditions (Hypo-sEV) exert better therapeutic effects on lipopolysaccharide (LPS)-induced inflammatory osteolysis than those cultured under normoxic conditions (Nor-sEV) by simultaneously inhibiting the macrophage inflammatory response and osteoclastogenesis. In this study, we show that hypoxia significantly induces the release of sEV from DPSCs. Moreover, Hypo-sEV exhibit significantly improved efficacy in promoting M2 macrophage polarization and suppressing osteoclast formation to alleviate LPS-induced inflammatory calvarial bone loss compared with Nor-sEV. Mechanistically, hypoxia preconditioning markedly alters the miRNA profiles of DPSC-sEV. MiR-210-3p is enriched in Hypo-sEV, and can simultaneously induce M2 macrophage generation and inhibit osteoclastogenesis by targeting NF-κB1 p105, which attenuates osteolysis. Our study suggests a promising potential for hypoxia-induced DPSC-sEV to treat inflammatory or infective osteolysis and identifies a novel role of miR-210-3p in concurrently hindering osteoclastogenesis and macrophage inflammatory response by inhibiting NF-kB1 expression.

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Hypoxia promotes the release of sEV from DPSCs.

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Hypoxia-induced DPSC-sEV (Hypo-sEV) show increased potential to inhibit inflammatory osteolysis.

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The miR-210-3p enriched in Hypo-sEV contributes to therapeutic effects of Hypo-sEV.

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MiR-210-3p concurrently induces M2 macrophage generation and inhibits osteoclastogenesis by targeting NF-κB1.

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Hypoxia-induced DPSC-sEV represent a promising therapy for inflammatory osteolysis.

Differential Spleen miRNA Expression Profile of Beagle Dogs Infected with Toxocara canis

Toxocara canis is an unnoticed zoonotic helminth that causes severe disease in animals and humans. The spleen has a wide range of immunological functions in protecting the host against infection by many pathogens, but the function of the spleen in T. canis infection is still to be clarified, especially for the role of spleen microRNAs (miRNAs). In this study, deep sequencing of spleen RNA samples of 18 Beagle puppies was conducted to uncover the miRNAs expression profiling at 24 h post-infection (hpi), 96 hpi, and 36 days post infection (dpi). A total of 20, 34, and 19 differentially expressed miRNAs (DEmiRNAs) were identified at 24 hpi, 96 hpi, and 36 dpi, respectively. These DEmiRNAs (e.g., cfa-miR-206, cfa-miR-331, and cfa-miR-339) could play critical roles in Beagle puppies against T. canis infection, such as influencing inflammatory and immune-related cells and cytokines, by regulating target genes that are tightly associated with host immune function and enriched in immune response and immune pathways based on GO annotation and KEGG enrichment analysis. The current study discovered marked alterations of spleen miRNAs after T. canis infection, with potential effects on the pathogenesis of toxocariasis.

miRNAs in the regulation of mTOR signaling and host immune responses: The case of Leishmania infections

Micro RNAs (miRNAs), as regulators of gene expression at the post-transcriptional level, can respond to/or interact with cell signaling and affect the pathogenesis of different diseases/infections. The interaction/crosstalk of miRNAs with various cellular signaling networks including mTOR (as a master regulator of signaling relevant to different cellular mechanisms) might lead to the initiation, progression or restriction of certain disease processes. There are numerous studies that have identified the crosstalk between regulatory miRNA expression and the mTOR pathway (or mTOR signaling regulated by miRNAs) in different diseases which has a dual function in pathogenesis. However, the corresponding information in parasitic infections remains scarce. miRNAs have been suggested as specific targets for therapeutic strategies in several disorders such as parasitic infections. Thus, the targeting of miRNAs (as the modulators/regulators of mTOR) by small molecules and RNA-based therapeutics and consequently managing and modulating mTOR signaling and the downstream/related cell signaling/pathways might shed some light on the design of new therapeutic strategies against parasitic diseases, including Leishmaniasis. Accordingly, the present study attempts to highlight the importance of the crosstalk between regulatory miRNAs and mTOR signaling, and to review the relevant insights into parasitic infections by focusing specifically on Leishmania.

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.

Apelin-13 Attenuates Lipopolysaccharide-Induced Inflammatory Responses and Acute Lung Injury by Regulating PFKFB3-Driven Glycolysis Induced by NOX4-Dependent ROS

Purpose

Acute lung injury (ALI) is a life-threatening condition with limited therapeutic options. Macrophage inflammation plays a key role in the development of ALI. Abnormal glycolysis of macrophages contributes to the inflammatory response. However, the role of macrophage glycolysis in ALI still requires investigation. Apelin-13 has been shown to protect against ALI, whereas the underlying mechanisms remain unclear. In this study, we explored the effect of apelin-13 on lipopolysaccharide (LPS)-induced inflammation and ALI via regulation of glycolysis by modulating redox homeostasis in macrophages.

Methods

Serums from 34 patients with sepsis and 13 healthy volunteers were analyzed. In vivo, the protective effect of apelin-13 against LPS-induced ALI was evaluated using a mouse model of LPS-induced ALI. In vitro, mouse bone marrow macrophages (BMDMs) were pretreated with the antioxidant, NADPH oxidase (NOX) 4 (NOX4) small-interfering RNA (siRNA), the 6-phosphofructo-2 -kinase/fructose- 2,6-biphosphatase 3 (PFKFB3) siRNA, or the PFKFB3 overexpression plasmid before exposure to LPS.

Results

Serum apelin-13 levels were significantly elevated in patients with sepsis and sepsis-associated acute respiratory distress syndrome (ARDS) (P<0.0001). In vivo, apelin-13 suppressed LPS-induced ALI and inflammatory cytokine production (P<0.05). Furthermore, apelin-13 reduced hydrogen peroxide (H₂O₂) content, NOX4 protein levels, and glycolysis. In vitro, LPS stimulation elevated NOX4 protein levels and reactive oxygen species (ROS) production (P<0.05). These changes resulted in the accumulation of glycolysis in BMDMs. Treatment with antioxidant or NOX4 siRNA inhibited LPS-induced glycolysis and inflammatory cytokine production (P<0.05). Moreover, in vitro experiments revealed that PFKFB3 regulates the release of pro-inflammatory cytokines by modulating glycolysis. In contrast, the action of apelin-13 opposed the effects of LPS.

Conclusion

In conclusion, apelin-13 protects against LPS-induced inflammatory responses and ALI by regulating PFKFB3-driven glycolysis induced by NOX4-dependent ROS.

The Triangle Relationship Between Long Noncoding RNA, RIG-I-like Receptor Signaling Pathway, and Glycolysis

Long noncoding RNA (LncRNA), a noncoding RNA over 200nt in length, can regulate glycolysis through metabolic pathways, glucose metabolizing enzymes, and epigenetic reprogramming. Upon viral infection, increased aerobic glycolysis providzes material and energy for viral replication. Mitochondrial antiviral signaling protein (MAVS) is the only protein-specified downstream of retinoic acid-inducible gene I (RIG-I) that bridges the gap between antiviral immunity and glycolysis. MAVS binding to RIG-I inhibits MAVS binding to Hexokinase (HK2), thereby impairing glycolysis, while excess lactate production inhibits MAVS and the downstream antiviral immune response, facilitating viral replication. LncRNAs can also regulate antiviral innate immunity by interacting with RIG-I and downstream signaling pathways and by regulating the expression of interferons and interferon-stimulated genes (ISGs). Altogether, we summarize the relationship between glycolysis, antiviral immunity, and lncRNAs and propose that lncRNAs interact with glycolysis and antiviral pathways, providing a new perspective for the future treatment against virus infection, including SARS-CoV-2.

Computational repurposing of therapeutic small molecules from cancer to pulmonary hypertension

Cancer therapies are being considered for treating rare noncancerous diseases like pulmonary hypertension (PH), but effective computational screening is lacking. Via transcriptomic differential dependency analyses leveraging parallels between cancer and PH, we mapped a landscape of cancer drug functions dependent upon rewiring of PH gene clusters. Bromodomain and extra-terminal motif (BET) protein inhibitors were predicted to rely upon several gene clusters inclusive of galectin-8 (LGALS8). Correspondingly, LGALS8 was found to mediate the BET inhibitor–dependent control of endothelial apoptosis, an essential role for PH in vivo. Separately, a piperlongumine analog’s actions were predicted to depend upon the iron-sulfur biogenesis gene ISCU. Correspondingly, the analog was found to inhibit ISCU glutathionylation, rescuing oxidative metabolism, decreasing endothelial apoptosis, and improving PH. Thus, we identified crucial drug-gene axes central to endothelial dysfunction and therapeutic priorities for PH. These results establish a wide-ranging, network dependency platform to redefine cancer drugs for use in noncancerous conditions.

IL-13 Derived Type 2 Innate Lymphocytes Ameliorates Cardiomyocyte Apoptosis Through STAT3 Signaling Pathway

The involvement of cardiomyopathy during sepsis means higher mortality and prolonged length of hospital stay. Many efforts have been made to alleviate the apoptosis of cardiomyocytes in sepsis. The huge potential of IL-13 in tissue repair has attracted increasing attention. In the present study, we used LPS-treated mice or primary cardiomyocytes as a sepsis model to explore the anti-apoptotic ability of IL-13. It was found that an increased level of exogenous IL-13 was beneficial to the recovery of heart function in sepsis, and this anti-apoptotic effect of IL-13 was probably through enhancing the phosphorylation of STAT3 Ser727. In addition, we identified that the heart protective effect of IL-13 was associated with type 2 innate lymphocytes (ILC2). All these findings may provide a potential promising treatment for sepsis-induced cardiomyopathy.

Hypoxia-induced miR-210 modulates the inflammatory response and fibrosis upon acute ischemia

Hypoxia-induced miR-210 is a crucial component of the tissue response to ischemia, stimulating angiogenesis and improving tissue regeneration. Previous analysis of miR-210 impact on the transcriptome in a mouse model of hindlimb ischemia showed that miR-210 regulated not only vascular regeneration functions, but also inflammation. To investigate this event, doxycycline-inducible miR-210 transgenic mice (Tg-210) and anti-miR-210 LNA-oligonucleotides were used. It was found that global miR-210 expression decreased inflammatory cells density and macrophages accumulation in the ischemic tissue. To dissect the underpinning cell mechanisms, Tg-210 mice were used in bone marrow (BM) transplantation experiments and chimeric mice underwent hindlimb ischemia. MiR-210 overexpression in the ischemic tissue was sufficient to increase capillary density and tissue repair, and to reduce inflammation in the presence of Wt-BM infiltrating cells. Conversely, when Tg-210-BM cells migrated in a Wt ischemic tissue, dysfunctional angiogenesis, inflammation, and impaired tissue repair, accompanied by fibrosis were observed. The fibrotic regions were positive for α-SMA, Vimentin, and Collagen V fibrotic markers and for phospho-Smad3, highlighting the activation of TGF-β1 pathway. Identification of Tg-210 cells by in situ hybridization showed that BM-derived cells contributed directly to fibrotic areas, where macrophages co-expressing fibrotic markers were observed. Cell cultures of Tg-210 BM-derived macrophages exhibited a pro-fibrotic phenotype and were enriched with myofibroblast-like cells, which expressed canonical fibrosis markers. Interestingly, inhibitors of TGF-β type-1-receptor completely abrogated this pro-fibrotic phenotype. In conclusion, a context-dependent regulation by miR-210 of the inflammatory response was identified. miR-210 expression in infiltrating macrophages is associated to improved angiogenesis and tissue repair when the ischemic recipient tissue also expresses high levels of miR-210. Conversely, when infiltrating an ischemic tissue with mismatched miR-210 levels, macrophages expressing high miR-210 levels display a pro-fibrotic phenotype, leading to impaired tissue repair, fibrosis, and dysfunctional angiogenesis.