miR-21 and miR-146a: The microRNAs of inflammaging and age-related diseases

Extracellular vesicle-derived MicroRNAs as potential therapies for spinal cord and peripheral nerve injuries

Complete nerve regeneration is limited in current therapeutic approaches for spinal cord injuries (SCIs) and peripheral nerve injuries (PNIs). Extracellular vesicles (EVs) and microRNAs (miRNAs) play a pivotal role in intercellular communication by transporting various biomolecules, including miRNAs, to the recipient cells. Thus, they are promising targets for novel neural regeneration drugs. This comprehensive study examined the roles of EV-derived miRNAs in facilitating neural rejuvenation after SCI and PNI. It also explored the mechanisms by which they augment neuroprotection and promote cell viability. It also discusses their translational potential for treating nerve injury and evaluates their potential impact on advancements in nerve resurrection and prospective research in regenerative medicine. The findings may provide effective treatments and improve outcomes, as well as contribute to addressing the direction for the next studies, for the pathologies of SCI and PNI.

miRNome profile in blood samples upstream and downstream of the coronary lesion and arterial aortic root before and after angioplasty in subjects with chronic and acute coronary syndrome: A pilot observational study protocol (Plaque study)

Currently the mechanisms that lead an atherosclerotic plaque to become unstable and those that trigger the coagulative/thrombotic processes leading to acute coronary syndrome have yet to be clarified. It has been suggested a possible role of microRNAs in the physiopathology of the atherosclerotic process related to acute and chronic ischemic cardiomyopathy. However, no data exists on the correlation between microRNAs expression in coronary (upstream and downstream of the coronary lesion) and arterial (at the aortic root level) blood from patients with acute coronary syndromes (ACS) and chronic coronary syndromes (CCS) before and after angioplasty. The study's primary objective is to assess miRnome analysis in coronary and arterial blood sampling in ACS and CCS patients before and after angioplasty. The secondary objective is to analyze interleukin-6 and soluble ST2 levels in the peripheral plasma samples before and after angioplasty. Ten patients with ACS and ten patients with CCS will be enrolled. Coronary stenosis treated with angioplasty will be located in the proximal segments of the three main vessels: the anterior interventricular artery, the circumflex artery, and the right coronary artery. The angioplasty procedure will be performed according to standard clinical practice. Before and after angioplasty, blood samples upstream and downstream of the coronary lesion will be taken, arterial sampling at the aortic root level will be performed, and peripheral venous blood will be collected. The expression of serum microRNAs will be analyzed by Next-generation sequencing. Quantitative analysis of pro- and anti-inflammatory molecules such as interleukin-6 and the soluble form of the soluble ST2 will be performed on various blood samples. This study is registered in ClinicalTrials.Gov on October 30, 2023 (ID NCT06103357).

Inflammatory Macrophage-Targeted Atherosclerosis Treatment by miRNA-Delivered, MRI-Visible, and Anti-Inflammatory Nanomedicine

Atherosclerosis, a principal cause of fatal cardiovascular diseases, is fundamentally a chronic inflammatory disease. Addressing this, the combined regulation of oxidative stress and inflammation through synergistic modalities offers an efficient therapeutic avenue. In this work, we rationally designed and engineered a highly efficient functional nanosystem, referred to as polydopamine nanoparticles doped with arginine and gadolinium ions (AGPDAR-146a), for the targeted delivery of therapeutic oligonucleotides, specifically microRNA-146a (miR-146a), to inflammatory macrophages within atherosclerotic plaques. AGPDAR-146a nanoparticles effectively load and deliver miR-146a, achieving enhanced accumulation in inflammatory macrophages through the specific interaction between miR-146a and class A scavenger receptors. Functionally, AGPDAR-146a nanoparticles excel in eliminating reactive oxygen species and exert anti-inflammatory effects, principally by modulating the nuclear factor kappa-light-chain-enhancer of activated B cells pathway and the interferon regulatory factor 5 protein, consequently helping to reduce and stabilize atherosclerotic plaques. Additionally, the intrinsic T1 magnetic resonance imaging capability of AGPDAR-146a nanoparticles enables real-time visualization of the progression of plaque inflammation. Therefore, the engineered nanosystem not only underscores the therapeutic potential of miR-146a in atherosclerosis but also illustrates a versatile microRNA delivery strategy applicable to various diseases characterized by oxidative stress and inflammation.

Geroprotective applications of oleuropein and hydroxytyrosol through the hallmarks of ageing

Geroprotectors are compounds that target the underlying mechanisms of ageing to delay the onset of age-related diseases and extend both lifespan and health span. As ageing is driven by the accumulation of cellular damage, DNA instability, epigenetic changes, mitochondrial dysfunction, and chronic inflammation, the concept of geroprotection focuses on compounds that can mitigate these processes. Oleuropein (OLE) and its derivative hydroxytyrosol (HT), both phenolic molecules derived from Olea europaea (olive tree), have gained significant attention as potential geroprotectors due to their potent antioxidant and anti-inflammatory properties. These phytochemicals, central to the Mediterranean diet, activate key molecular pathways such as nuclear factor erythroid 2-related factor 2, reducing oxidative stress and modulating inflammatory responses. Through these mechanisms, OLE and HT help counteract inflammageing, a critical factor in age-related dysfunction. This review highlights the role of OLE and HT as geroprotective agents, emphasising their ability to target the hallmarks of ageing and their potential to improve health span by slowing the progression of age-related conditions. With proven efficacy in various biological models, these compounds represent promising tools in the ongoing search for strategies to enhance the quality of life in ageing populations.

NLRP3 Inflammasome-mediated pyroptosis in acute lung injury: Roles of main lung cell types and therapeutic perspectives

The NLRP3 inflammasome plays a pivotal role in the pathogenesis of acute lung injury (ALI) by regulating pyroptosis, a highly inflammatory form of programmed cell death. NLRP3-mediated pyroptosis leads to alveolar epithelial cell injury, increased pulmonary microvascular endothelial permeability, excessive alveolar macrophage activation, and neutrophil dysfunction, collectively driving ALI progression. In addition to the classical NLRP3-dependent pathway, the non-canonical pyroptosis pathway (caspase-4/5/11) also contributes to ALI by inducing pyroptotic cell death in AECs and ECs, further amplifying NLRP3 activation through damage-associated molecular patterns (DAMP) release. Moreover, neutrophils (NE) pyroptosis exhibits dual roles in ALI, as it enhances pathogen clearance but also exacerbates excessive inflammation and tissue damage, highlighting the complexity of its regulation. Targeting the NLRP3 inflammasome and pyroptotic pathways has emerged as a promising therapeutic strategy for ALI. Various NLRP3 inhibitors (e.g., MCC950, CY-09, OLT1177) and pyroptosis inhibitors have demonstrated significant anti-inflammatory and tissue-protective effects in preclinical models. However, the clinical translation of NLRP3-targeted therapies remains challenging due to off-target effects, potential immunosuppression, lack of patient stratification strategies, and compensatory activation of alternative inflammasomes (e.g., AIM2, NLRC4). Future studies should focus on optimizing the selectivity of NLRP3 inhibitors, developing personalized therapeutic approaches, and exploring combination strategies to enhance their clinical applicability in ALI.

Eicosapentaenoic acid (EPA) reduced lipopolysaccharide-stimulated inflammatory response of RAW264.7 cells via the miR-125b-5p/CREB axis

Inflammation represents an adaptive physiological response of body immune system to infection or tissue damage, which may be regulated by food supplementation. Eicosapentaenoic acid (EPA) has multi-functions and its anti-inflammatory effect has gained great attention. This study aimed to address the exact molecular mechanism underlying its inflammatory control. The results showed that EPA decreased lipopolysaccharide-induced inflammatory response in RAW264.7 cells by modulating the production of cellular cytokines. In addition, EPA downregulated miR-125b-5p, which showed pro-inflammatory effect and its forced expression attenuated EPA's anti-inflammatory activity. Moreover, the cAMP-responsive element-binding protein (CREB) is targeted by miR-125b-5p. CREB overexpression reduced inflammation probably via modulating the PGC-1α/NF-κB pathway, which resembled the effect of EPA pre-treatment. Therefore, EPA exhibited anti-inflammatory activity by targeting the miR-125b-5p/CREB axis, which modulated the production of inflammatory mediators probably via transcription control. This study provides insights into microRNA-mediated action mechanism and facilitates the relief of inflammation-associated diseases by food ingredients.

Circulating microRNAs demonstrate limited diagnostic potential for diabetic retinopathy in the population of Kazakhstan

Background

Diabetic retinopathy (DR) is the most common complication of diabetes, leading to blindness. The asymptomatic onset and the existing difficulties in diagnosing warrant the search for biomarkers that can facilitate the early diagnosis of DR. The aim of this study was to evaluate the potential of plasma microRNAs (miRNAs), which have previously been shown to be involved in the pathogenesis of DR and differentially expressed in plasma/serum of patients, as biomarkers for DR in the Kazakhstani population.

Materials and Methods

Using quantitative RT-PCR, we compared the levels of ten candidate miRNAs in plasma among three groups: type 2 diabetes mellitus (T2DM) patients with DR (DR patients, N = 100), T2DM patients without DR (noDR patients, N = 98), and healthy controls (N = 30).

Results

Level of miR-423-3p was significantly reduced in DR patients compared to noDR patients (pFDR = 5.4 × 10-3). Levels of miR-423-3p and miR-221-3p were significantly reduced in DR patients compared to controls (pFDR = 5.4 × 10-3 and 0.024, respectively ), level of miR-23a-3p was significantly reduced in noDR patients compared to controls (pFDR = 0.047), levels of miR-221-3p and miR-23a-3p were significantly reduced in T2DM patients (combined group) compared to controls (pFDR = 0.047, and 0.049, respectively). Also, there were several significant differences between groups formed based on clinical-pathological characteristics, but none of these results remained significant after adjustment for multiple comparisons. Correlation analysis revealed weak associations between the levels of miR-423 and miR-221-3p and DR staging (pFDR = 1.3 × 10-3 and 0.026, respectively), and fair associations between the levels of miR-29b-3p and miR-328-3p and diabetes duration in noDR patients (pFDR = 8.8 × 10-3 and 0.016, respectively). According to receiver operating characteristic (ROC) analysis, only miR-23a-3p can be considered a potential biomarker with moderate informativeness for diagnosing proliferative DR (PDR); however, a larger sample size is needed to verify this finding. Furthermore, the small magnitude of observed changes in miRNA levels between groups significantly complicates classification.

Conclusions

Due to the low specificity and small magnitude of deviations from the norm, the studied miRNAs have low potential in the diagnosis of DR.

Injectable ECM-mimetic dynamic hydrogels abolish ferroptosis-induced post-discectomy herniation through delivering nucleus pulposus progenitor cell-derived exosomes

Discectomy-induced ferroptosis of nucleus pulposus cells (NPCs) contributes to postoperative lumbar disc herniation (LDH) recurrence and intervertebral disc degeneration (IDD). We discover that nucleus pulposus progenitor cells (NPPCs) could imprint ferroptosis resistance into NPCs through exosome-dependent intercellular transmission of miR-221-3p. Based on these findings, we first develop synthetically-tailored NPPC-derived exosomes with enhanced miR-221-3p expression and NPC uptake capacity, which are integrated into an injectable hydrogel based on extracellular matrix (ECM) analogues. The ECM-mimetic hydrogel (HACS) serves as a biomimetic filler for the post-operative care of herniated discs, which could be facilely injected into the discectomy-established nucleus pulposus (NP) cavity for localized treatment. HACS-mediated in-situ exosome release in the NP cavity enables marked ferroptosis inhibition in NPCs that not only prevents LDH recurrence but also reverses the IDD symptoms, leading to robust restoration of NP structure and functions. In summary, this study offers a promising approach for treating disc herniation.

Start small, think big: MicroRNAs in diabetes mellitus and relevant cardiorenal-liver metabolic health spectrum

Diabetes mellitus (DM), co-existing with metabolic disorder of cardio-renal-liver, is one of the most difficult problems in medicine that attracts global concern with high mortality. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules that negatively regulates gene expression and exerts active against a large proportion of the transcriptome, due to their high evolutionary conservation. Emerging evidence prove that miRNAs are involved in the pathogenesis of DM and associated metabolic disorders, manifested by their variable alteration in the blood, urine, tissues, or organs, principally contributing to modulate the interconnections between DM and cardio-renal-liver metabolism. Mechanistically, miRNAs regulate various biological processes, such as metabolism of insulin, lipid, glucose, inflammatory response, fibrosis, oxidative stress, apoptosis, and angiogenesis, etc. This review emphasizes the function of miRNAs and highlights the physiopathological regulation of miRNA in DM and related complications, especially the dysfunction of cardiovascular system, kidneys, and liver, with the aim of providing promising biomarkers for assisting early diagnosis of DM with cardio-renal-liver- specific metabolic disorders, as well as for the development of miRNA-targeting agents.

Probiotics Exert Gut Immunomodulatory Effects by Regulating the Expression of Host miRNAs

Probiotics exert a diverse range of immunomodulatory effects on the human gut immune system. These mechanisms encompass strengthening the intestinal mucosal barrier, inhibiting pathogen adhesion and colonization, stimulating immune modulation, and fostering the production of beneficial substances. As a result, probiotics hold significant potential in the prevention and treatment of various conditions, including inflammatory bowel disease and colorectal cancer. A pivotal mechanism by which probiotics achieve these effects is through modulating the expression of host miRNAs. miRNAs, non-coding RNA molecules, are vital regulators of fundamental biological processes like cell growth, differentiation, and apoptosis. By interacting with mRNAs, miRNAs can either promote their degradation or repress their translation, thereby regulating gene expression post-transcriptionally and modulating the immune system. This review provides a comprehensive overview of how probiotics modulate gut immune responses by altering miRNA expression levels, both upregulating and downregulating specific miRNAs. It further delves into how this modulation impacts the host's resistance to pathogens and susceptibility to diseases, offering a theoretical foundation and practical insights for the clinical utilization of probiotics in disease prevention and therapy.

Sustained release of miR-21 carried by mesenchymal stem cell-derived exosomes from GelMA microspheres inhibits ovarian granulosa cell apoptosis in premature ovarian insufficiency

Background

Premature ovarian insufficiency (POI) refers to the severe decline or failure of ovarian function in women younger than 40 years of age. It is a serious hazard to women's physical and mental health, but current treatment options are limited. Mesenchymal stem cell-derived exosomes (MSC-Exo) exhibit promising potential as a therapeutic approach for POI. However, their clinical application is hindered by their instability and low long-term retention rate in vivo.

Methods and results

In this study, miR-21 was identified as the predominant miRNA with low-expression in follicular fluid exosomes of POI patients and was shown to possess antiapoptotic activity. Next, we loaded miR-21 agomir to MSC-Exo to form Agomir21-Exo, which significantly reversed the apoptosis of granulosa cells in vitro. Moreover, we successfully developed GelMA hydrogel microspheres for encapsulating Agomir21-Exo through microfluidic technology, named GelMA-Ag21Exo, which had good injectability and significantly enhanced the stability and long-term retention of Agomir21-Exo in mice through sustained release. The release of Agomir21-Exo from GelMA-Ag21Exo notably alleviated the apoptosis of ovarian granulosa cells and improved the ovarian reserve and fertility in POI mice.

Conclusion

Our findings illustrate that activating miR-21 through Agomir21-Exo could improve the function of ovarian granulosa cells. The GelMA-Ag21Exo enhanced the exosome-based therapeutic efficacy of the Agomir21-Exo in vivo. These findings provide a novel and promising treatment strategy for POI patients.

Effects of miR-21/NLRP3 on Blue Light-Induced Retinal Neurodegeneration in Mice

PURPOSE

Age-related macular degeneration (AMD) is a chronic retinal disease that can lead to blindness. While the NLR family pyrin domain containing 3 (NLRP3) inflammasome is implicated in AMD, the specific roles of miR-21 and NLRP3 in AMD-related inflammation remain unclear. Therefore, this study aimed to investigate the roles of miR-21 and NLRP3 in blue light-induced neurodegeneration in the mouse retina.

METHODS

A mouse model of retinal light damage was established through three months of blue light exposure (BLE). The experimental groups comprised the Control (Ctrl), BLE, BLE + miR-nc, and BLE + miR-21 inhibitor groups. The microRNAs were administered via intravitreal injections once per week. After successful modeling, changes in visual function and retinal morphology were investigated by using electroretinography and hematoxylin and eosin staining, respectively. Photoreceptor apoptosis was assessed using the TdT-mediated dUTP nick-end labeling assay. Immunofluorescence was used to detect and locate microglia and NLRP3 expression in the mouse retina. The expression of miR-21, NLRP3, and downstream factors in the retinas of each group was measured using qRT-PCR and western blotting.

RESULTS

In the BLE and BLE + miR-nc groups, there was a decrease in visual function and retinal thickness, an increase in retinal ganglion cell injury and photoreceptor cell apoptosis, and elevated microglia activity in the retina, as evidenced by their migration to the outer retinal layer. In addition, the expression of miR-21, NLRP3, and downstream factors was increased in the BLE and BLE + miR-nc groups compared to that in the control group. However, intravitreal injection of the miR-21 inhibitor reduced miR-21 expression in the retina and significantly inhibited the activation of the NLRP3 inflammasome, effectively alleviating retinal photodamage caused by BLE.

CONCLUSIONS

This study indicates that miR-21 may mitigate blue-light-induced retinal neurodegeneration by reducing the activation of the NLRP3 inflammasome in the mouse retina.

The Interplay Between Obesity and Aging in Breast Cancer and Regulatory Function of MicroRNAs in This Pathway

Breast cancer (BC) is a significant contributor to cancer-related deaths in women, and it has complex connections with obesity and aging. This review explores the interaction between obesity and aging in relation to the development and progression of BC, focusing on the controlling role of microRNAs (miRNAs). Obesity, characterized by excess adipose tissue, contributes to a proinflammatory environment and metabolic dysregulation, which are important in tumor development. Aging, associated with cellular senescence and systemic changes, further exacerbates these conditions. miRNAs, small noncoding RNAs that regulate gene expression, play key roles in these processes, impacting pathways involved in cell proliferation, apoptosis, and cancer metastasis, either as tumor suppressors or oncogenes. Importantly, specific miRNAs are implicated in mediating the impact of obesity and aging on BC. Exploring the regulatory networks controlled by miRNAs provides valuable information on new targets for therapy and predictive markers, demonstrating the potential for using miRNA-based interventions to treat BC in obese and elderly individuals. This review emphasizes the importance of integrated research strategies to understand the complex connections between obesity, aging, and miRNA regulation in BC.

Combined effect of exercise and curcumin on inflammation-associated microRNAs and cytokines in old male rats: A promising approach against inflammaging

Purpose

Inflammation serves as a key contributor to various diseases, necessitating the discovery of new treatment approaches to address its causative role.

Methods

The study involved 35 male Wistar rats, including 7 young rats (3-month-old; 200-250 g) in the Young control group and 28 aged rats (18-month-old; 400-450 g) randomly distributed among the Old control, Exercise, Curcumin, and Exercise + Curcumin groups. During an 8-week period, the Exercise group underwent running on the treadmill (17 m/min), while those in the Curcumin group were supplied with daily curcumin doses (50 mg/kg) through gavage. Upon completion of the study, serum samples from each group were collected for evaluating interleukin-6 (IL-6), interleukin-1β (IL-1β), interleukin-10 (IL-10), and Tumor Necrosis Factor-α (TNF-α) levels using ELISA; malondialdehyde (MDA) by enzymatic assay; and miR-21 and miR-146a by RT-PCR.

Results

Our findings revealed that the Old control group, in contrast to the Young control group, showed a significant reduction in IL-10 serum levels, while MDA, TNF-α, IL-1β, and IL-6 serum levels were significantly elevated. Additionally, the expression of inflammatory microRNAs (miRNAs), miR-21 and miR-146a, was significantly enhanced in the Old control rats compared with the Young control group. Exercise and curcumin treatment alone resulted in an improvement in the expression of the markers and miRNAs associated with inflammation. Furthermore, when exercise and curcumin were administered simultaneously, a synergistic effect was observed compared to the exercise or curcumin alone groups.

Conclusion

Curcumin and exercise, individually and synergistically in combination, effectively reduced inflammation in aged rats, likely due to decreased oxidative stress and MDA levels mediated by miR-21 and miR-146a downregulation.

Urinary Proteome and Exosome Analysis Protocol for the Discovery of Respiratory Diseases Biomarkers

This study aims to develop a protocol for respiratory disease-associated biomarker discovery by combining urine proteome studies with urinary exosome components analysis (i.e., miRNAs). To achieve this, urine was DTT treated to decrease uromodulin, then concentrated and ultracentrifuged. Proteomic analyses of exosome-free urine were performed using LC-MS/MS. Simultaneously, miRNA expression from urine exosomes was measured using either RTqPCR (pre-amplification) or nCounter Nanostring (non-amplication) analyses. We detected 548 different proteins in exosome-free urine samples (N = 5) with high confidence (FDR < 1%), many of them being expressed in different non-renal tissues. Specifically, lung-related proteins were overrepresented (Fold enrichment = 1.31; FDR = 0.0335) compared to whole human proteome, and 10-15% were already described as protein biomarkers for several pulmonary diseases. Urine proteins identified belong to several functional categories important in respiratory pathology. We could confirm the expression of miRNAs previously connected to respiratory diseases (i.e., miR-16-5p, miR-21-5p, miR-146a-5p, and miR-215-5p) in urine exosomes by RTqPCR. Finally, we detected 333 miRNAs using Nanostring, 15 of them up-regulated in T2high asthma (N = 4) compared to T2low asthma (N = 4) and healthy subjects (N = 4). Therefore, this protocol combining the urinary proteome (exosome free) with the study of urinary exosome components (i.e., miRNAs) holds great potential for molecular biomarker discovery of non-renal and particularly respiratory pathologies.

Can miRNAs in MSCs-EVs Offer a Potential Treatment for Hypoxic-ischemic Encephalopathy?

Neonatal hypoxic-ischemic encephalopathy (HIE) is a critical condition resulting from impaired oxygen and blood flow to the brain during birth, leading to neuroinflammation, neuronal apoptosis, and long-term neurological deficits. Despite the use of therapeutic hypothermia, current treatments remain inadequate in fully preventing brain damage. Recent advances in mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) offer a novel, cell-free therapeutic approach, as these EVs can cross the blood-brain barrier (BBB) and deliver functional microRNAs (miRNAs) to modulate key pathways involved in inflammation and neuroprotection. This review examines how specific miRNAs encapsulated in MSC-EVs-including miR-21, miR-124, miR-146, and the miR-17-92 cluster-target the complex inflammatory responses that drive HIE pathology. By modulating pathways such as NF-κB, STAT3, and PI3K/Akt, these miRNAs influence neuroinflammatory processes, reduce neuronal apoptosis, and promote tissue repair. The aim is to assess the therapeutic potential of miRNA-loaded MSC-EVs in mitigating inflammation and neuronal damage, thus addressing the limitations of current therapies like therapeutic hypothermia.

Extracellular Vesicles: Advanced Tools for Disease Diagnosis, Monitoring, and Therapies

Extracellular vesicles (EVs) are a heterogeneous group of membrane-encapsulated vesicles released by cells into the extracellular space. They play a crucial role in intercellular communication by transporting bioactive molecules such as proteins, lipids, and nucleic acids. EVs can be detected in body fluids, including blood plasma, urine, saliva, amniotic fluid, breast milk, and pleural ascites. The complexity and diversity of EVs require a robust and standardized approach. By adhering to standardized protocols and guidelines, researchers can ensure the consistency, purity, and reproducibility of isolated EVs, facilitating their use in diagnostics, therapies, and research. Exosomes and microvesicles represent an exciting frontier in modern medicine, with significant potential to transform the diagnosis and treatment of various diseases with an important role in personalized medicine and precision therapy. The primary objective of this review is to provide an updated analysis of the significance of EVs by highlighting their mechanisms of action and exploring their applications in the diagnosis and treatment of various diseases. Additionally, the review addresses the existing limitations and future potential of EVs, offering practical recommendations to resolve current challenges and enhance their viability for clinical use. This comprehensive approach aims to bridge the gap between EV research and its practical application in healthcare.

Biological Aging and Venous Thromboembolism: A Review of Telomeres and Beyond

Although venous thromboembolism (VTE) is the third most common cardiovascular disease, and the risk of VTE increases sharply with advancing age, approximately 40% of VTE cases are currently classified as unprovoked, highlighting the importance of risk factor research. While chronological aging is associated with the risk of VTE, the association with biological aging remains unclear. Biological aging is highly complex, influenced by several dysregulated cellular and biochemical mechanisms. In the last decade, advancements in omics methodologies provided insights into the molecular complexity of biological aging. Techniques such as high-throughput genomics, epigenomics, transcriptomics, proteomics, and metabolomics analyses identified and quantified numerous epigenetic markers, transcripts, proteins, and metabolites. These methods have also revealed the molecular alterations organisms undergo as they age. Despite the progress, there is still a lack of consensus regarding the methods for assessing and validating these biomarkers, and their application lacks standardization. This review gives an overview of biomarkers of biological aging, including telomere length, and their potential role for VTE. Furthermore, we critically examine the advantages and disadvantages of the proposed methods and discuss possible future directions for investigating biological aging in VTE.

The function of miRNAs in the immune system's inflammatory reaction to heart failure

Heart failure is the end stage of cardiovascular disease, with high morbidity and mortality rates worldwide. Heart failure is associated with long-term and insufficient inhibition of inflammatory response. miRNA is a class of endogenous, non-coding, single-stranded small RNA molecules, that can regulate gene expression through translational inhibition or degradation of targeted mRNA, widely regulate myocardial remodeling, inflammatory response, and other pathological processes, and play an important regulatory role in the occurrence and development of cardiovascular diseases. This article reviews the role of miRNA in the inflammatory response in heart failure.

Research progress on the role of extracellular vesicles in the pathogenesis of diabetic kidney disease

Diabetic kidney disease (DKD) is a serious complication of diabetes mellitus (DM) and has become the main cause of end-stage renal disease worldwide. In recent years, with the increasing incidence of DM, the pathogenesis of DKD has received increasing attention. The pathogenesis of DKD is diverse and complex. Extracellular vesicles (EVs) contain cell-derived membrane proteins, nucleic acids (such as DNA and RNA) and other important cellular components and are involved in intercellular information and substance transmission. In recent years, an increasing number of studies have confirmed that EVs play an important role in the development of DKD. The purpose of this paper is to explain the potential diagnostic value of EVs in DKD, analyze the mechanism by which EVs participate in intercellular communication, and explore whether EVs may become drug carriers for targeted therapy to provide a reference for promoting the implementation and application of exosome therapy strategies in clinical practice.

Exosomes in Central Nervous System Diseases: A Comprehensive Review of Emerging Research and Clinical Frontiers

Exosomes, nano-sized lipid bilayer vesicles, have garnered significant attention as mediators of cell communication, particularly within the central nervous system (CNS). Their unique properties, including high stability, low immunogenicity, and the ability to traverse the blood-brain barrier (BBB), position them as promising tools for understanding and addressing CNS diseases. This comprehensive review delves into the biogenesis, properties, composition, functions, and isolation of exosomes, with a particular focus on their roles in cerebrovascular diseases, neurodegenerative disorders, and CNS tumors. Exosomes are involved in key pathophysiological processes in the CNS, including angiogenesis, inflammation, apoptosis, and cellular microenvironment modification. They demonstrate promise in mitigating ischemic injury, regulating inflammatory responses, and providing neuroprotection across various CNS conditions. Furthermore, exosomes carry distinct biomolecules, offering a novel method for the early diagnosis and monitoring of CNS diseases. Despite their potential, challenges such as complex extraction processes, the heterogeneity of exosomal contents, and targeted delivery limitations hinder their clinical application. Nevertheless, exosomes hold significant promise for advancing our understanding of CNS diseases and developing novel therapeutic strategies. This manuscript significantly contributes to the field by highlighting exosomes' potential in advancing our understanding of CNS diseases, underscoring their unique value in developing novel therapeutic strategies and mediating cellular communication.

Common molecular basis for MASH and hepatitis C revealed via systems biology approach

Background

Metabolic dysfunction-associated steatohepatitis (MASH) is characterized by liver inflammation and damage caused by a buildup of fat in the liver. Hepatitis C, caused by hepatitis C virus (HCV), is a disease that can lead to liver cirrhosis, liver cancer, and liver failure. MASH and hepatitis C are the common causes of liver cirrhosis and hepatocellular carcinoma. Several studies have shown that hepatic steatosis is also a common histological feature of liver in HCV infected patients. However, the common molecular basis for MASH and hepatitis C remains poorly understood.

Methods

Firstly, differentially expressed genes (DEGs) for MASH and hepatitis C were extracted from the GSE89632, GSE164760 and GSE14323 datasets. Subsequently, the common DEGs shared among these datasets were determined using the Venn diagram. Next, a protein-protein interaction (PPI) network was constructed based on the common DEGs and the hub genes were extracted. Then, gene ontology (GO) and pathway analysis of the common DEGs were performed. Furthermore, transcription factors (TFs) and miRNAs regulatory networks were constructed, and drug candidates were identified. After the MASH and hepatitis C cell model was treated with predicted drug, the expression levels of the signature genes were measured by qRT-PCR and ELISA.

Results

866 common DEGs were identified in MASH and hepatitis C. The GO analysis showed that the most significantly enriched biological process of the DEGs was the positive regulation of cytokine production. 10 hub genes, including STAT1, CCL2, ITGAM, PTPRC, CXCL9, IL15, SELL, VCAM1, TLR4 and CCL5, were selected from the PPI network. By constructing the TF-gene and miRNA-gene network, most prominent TFs and miRNAs were screened out. Potential drugs screening shows that Budesonide and Dinoprostone may benefit patients, and cellular experiments showed that Budesonide effectively inhibited the expression of genes related to glycolipid metabolism, fibrosis, and inflammatory factors.

Conclusion

We extracted 10 hub genes between MASH and hepatitis C, and performed a series of analyses on the genes. Molecular docking and in vitro studies have revealed that Budesonide can effectively suppress the progression of MASH and hepatitis C. This study can provide novel insights into the potential drug targets and biomarkers for MASH and hepatitis C.

Unveiling the Predictive Model for Macrovascular Complications in Type 2 Diabetes Mellitus: microRNAs Expression, Lipid Profile, and Oxidative Stress Markers

To assay new circulating markers related to macrovascular complications (MVC) in type 2 diabetes mellitus (T2DM), we carried out a descriptive cross-sectional study. We recruited 30 controls (CG), 34 patients with T2DM (DG), and 28 patients with T2DM and vascular complications (DG+C); among them, 22 presented MVC. Peripheral blood was used to determine redox status (superoxide dismutase, SOD; catalase, CAT; glutathione reductase, GRd; glutathione peroxidase, GPx; glucose-6-phosphate dehydrogenase, G6PD) and markers of oxidative damage (advanced oxidation protein products, AOPP; lipid peroxidation, LPO), nitrite levels in plasma (NOx). Inflammatory markers (IL-1β, IL-6, IL-10, IL-18, MCP-1, TNF-α) and the relative expression of c-miRNAs were analyzed. The real-time PCR results showed that the expressions of miR-155-5p, miR-21-5p, miR-146a-3p, and miR-210-3p were significantly higher in the DG group compared to the CG. The DG+C group presented statistically relevant differences with CG for four miRs: the increased expression of miR-484-5p, miR-21-5p, and miR-210-3p, and decreased expression of miR-126a-3p. Moreover, miR-126a-3p was significantly less expressed in DG+C compared to DG. The application of binary logistic regression analysis and construction of receiving operator characteristic curves (ROC) revealed two models with high predictive values for vascular complications presence: (1) HbAc1, creatinine, total cholesterol (TC), LPO, GPx, SOD, miR-126, miR-484 (Exp(B) = 0.926, chi2 = 34.093, p < 0.001; AUC = 0.913). (2) HbAc1, creatinine, TC, IL-6, LPO, miR-126, miR-484 (Exp(B) = 0.958, Chi2 = 33.863, p < 0.001; AUC = 0.938). Moreover, our data demonstrated that gender, TC, GPx, CAT, and miR-484 were associated with MVC and exhibited higher predictive values (Exp(B) = 0.528, p = 0.024, Chi2 = 28.214, AUC = 0.904) than classical variables (Exp(B) 0.462, p = 0.007, Chi2 = 18.814, AUC = 0.850). miR-126, miR-484, IL-6, SOD, CAT, and GPx participate in vascular damage development in the studied diabetic population and should be considered for future studies.

Cleistocalyx nervosum var. paniala mitigates oxidative stress and inflammation induced by PM10 soluble extract in trophoblast cells via miR-146a-5p

Air pollution poses a significant global concern, notably impacting pregnancy outcomes through mechanisms such as DNA damage, oxidative stress, inflammation, and altered miRNA expression, all of which can adversely affect trophoblast functions. Cleistocalyx nervosum var. paniala, known for its abundance of anthocyanins with diverse biological activities including anti-mutagenic, antioxidant, and anti-inflammatory properties, is the focus of this study examining its effect on Particulate Matter 10 (PM10) soluble extract-induced trophoblast cell dysfunction via miRNA expression. The study involved the extraction of C. nervosum fruit using 70% ethanol, followed by fractionation with hexane, dichloromethane, and ethyl acetate. Subsequent testing for total phenolics, flavonoids, anthocyanins, and antioxidant activity revealed the ethyl acetate fraction (CN-EtOAcF) as possessing the highest phenolic and anthocyanin content along with potent antioxidant activity, prompting its selection for further investigation. In vitro studies on HTR-8/SVneo cells demonstrated that 5-10 µg/mL PM10 soluble extract exposure inhibited cell proliferation, migration, invasion, and induced apoptosis. However, pretreatment with 20-80 µg/mL CN-EtOAcF followed by 5 µg/mL PM10 soluble extract exposure exhibited protective effects against PM10 soluble extract-induced damage, including inflammation inhibition and intracellular ROS suppression. Notably, CN-EtOAcF down-regulated PM10-induced miR-146a-5p expression, with SOX5 identified as a potential target. Overall, CN-EtOAcF demonstrated the potential to protect against PM10-induced harm in trophoblast cells, suggesting its possible application in future therapeutic approaches.

MiR-146a-5p engineered hucMSC-derived extracellular vesicles attenuate Dermatophagoides farinae-induced allergic airway epithelial cell inflammation

INTRODUCTION

Allergic asthma is prevalent in children, with Dermatophagoides farinae as a common indoor allergen. Current treatments for allergic airway inflammation are limited and carry risks. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) show promise as a cell-free therapeutic approach. However, the use of engineered MSC-EVs for D. farinae-induced allergic airway epithelial cell inflammation remains unexplored.

METHODS

We generated miR-146a-5p-engineered EVs from human umbilical cord mesenchymal stem cells (hucMSCs) and established D. farinae-induced mouse and human bronchial epithelial cell allergic models. Levels of IL-1β, IL-18, IL-4, IL-5, IL-6, IL-10, IL-33, TNF-α and IgE were detected using ELISA. The relative TRAF6 and IRAK1 mRNA expression was quantified using qPCR assay and the NLRP3, NF-κB, IRAK1 and TRAF6 protein expression was determined using Western blotting. The regulatory effect of IRAK1 and TRAF6 by miR-146a-5p was examined using a dual luciferase reporter assay, and the nuclear translocation of NF-κB p65 into 16-HBE cells was evaluated using immunofluorescence assay.

RESULTS

Treatment with hucMSC-EVs effectively reduced allergic inflammation, while miR-146a-5p engineered hucMSC-EVs showed greater efficacy. The enhanced efficacy in alleviating allergic airway inflammation was attributed to the downregulation of IRAK1 and TRAF6 expression, facilitated by miR-146a-5p. This downregulation subsequently led to a decrease in NF-κB nuclear translocation, which in turn resulted in reduced activation of the NLRP3 inflammasome and diminished production of inflammatory cytokines, including IL-6, TNF-α, IL-1β and IL-18.

CONCLUSION

Our study underscores the potential of miR-146a-5p engineered hucMSC-EVs as a cell-free therapeutic strategy for D. farinae-induced allergic airway inflammation, offering a promising avenue for boosting anti-inflammatory responses.

MiRNA-132/212 encapsulated by adipose tissue-derived exosomes worsen atherosclerosis progression

BACKGROUND

Visceral adipose tissue in individuals with obesity is an independent cardiovascular risk indicator. However, it remains unclear whether adipose tissue influences common cardiovascular diseases, such as atherosclerosis, through its secreted exosomes.

METHODS

The exosomes secreted by adipose tissue from diet-induced obesity mice were isolated to examine their impact on the progression of atherosclerosis and the associated mechanism. Endothelial apoptosis and the proliferation and migration of vascular smooth muscle cells (VSMCs) within the atherosclerotic plaque were evaluated. Statistical significance was analyzed using GraphPad Prism 9.0 with appropriate statistical tests.

RESULTS

We demonstrate that adipose tissue-derived exosomes (AT-EX) exacerbate atherosclerosis progression by promoting endothelial apoptosis, proliferation, and migration of VSMCs within the plaque in vivo. MicroRNA-132/212 (miR-132/212) was detected within AT-EX cargo. Mechanistically, miR-132/212-enriched AT-EX exacerbates palmitate acid-induced endothelial apoptosis via targeting G protein subunit alpha 12 and enhances platelet-derived growth factor type BB-induced VSMC proliferation and migration by targeting phosphatase and tensin homolog in vitro. Importantly, melatonin decreases exosomal miR-132/212 levels, thereby mitigating the pro-atherosclerotic impact of AT-EX.

CONCLUSION

These data uncover the pathological mechanism by which adipose tissue-derived exosomes regulate the progression of atherosclerosis and identify miR-132/212 as potential diagnostic and therapeutic targets for atherosclerosis.

Spatiotemporal Dysregulation of Neuron-Glia Related Genes and Pro-/Anti-Inflammatory miRNAs in the 5xFAD Mouse Model of Alzheimer's Disease

Alzheimer's disease (AD), the leading cause of dementia, is a multifactorial disease influenced by aging, genetics, and environmental factors. miRNAs are crucial regulators of gene expression and play significant roles in AD onset and progression. This exploratory study analyzed the expression levels of 28 genes and 5 miRNAs (miR-124-3p, miR-125b-5p, miR-21-5p, miR-146a-5p, and miR-155-5p) related to AD pathology and neuroimmune responses using RT-qPCR. Analyses were conducted in the prefrontal cortex (PFC) and the hippocampus (HPC) of the 5xFAD mouse AD model at 6 and 9 months old. Data highlighted upregulated genes encoding for glial fibrillary acidic protein (Gfap), triggering receptor expressed on myeloid cells (Trem2) and cystatin F (Cst7), in the 5xFAD mice at both regions and ages highlighting their roles as critical disease players and potential biomarkers. Overexpression of genes encoding for CCAAT enhancer-binding protein alpha (Cebpa) and myelin proteolipid protein (Plp) in the PFC, as well as for BCL2 apoptosis regulator (Bcl2) and purinergic receptor P2Y12 (P2yr12) in the HPC, together with upregulated microRNA(miR)-146a-5p in the PFC, prevailed in 9-month-old animals. miR-155 positively correlated with miR-146a and miR-21 in the PFC, and miR-125b positively correlated with miR-155, miR-21, while miR-146a in the HPC. Correlations between genes and miRNAs were dynamic, varying by genotype, region, and age, suggesting an intricate, disease-modulated interaction between miRNAs and target pathways. These findings contribute to our understanding of miRNAs as therapeutic targets for AD, given their multifaceted effects on neurons and glial cells.

Post-Acute Sequelae and Mitochondrial Aberration in SARS-CoV-2 Infection

This review investigates links between post-acute sequelae of SARS-CoV-2 infection (PASC), post-infection viral persistence, mitochondrial involvement and aberrant innate immune response and cellular metabolism during SARS-CoV-2 infection. Advancement of proteomic and metabolomic studies now allows deeper investigation of alterations to cellular metabolism, autophagic processes and mitochondrial dysfunction caused by SARS-CoV-2 infection, while computational biology and machine learning have advanced methodologies of predicting virus-host gene and protein interactions. Particular focus is given to the interaction between viral genes and proteins with mitochondrial function and that of the innate immune system. Finally, the authors hypothesise that viral persistence may be a function of mitochondrial involvement in the sequestration of viral genetic material. While further work is necessary to understand the mechanisms definitively, a number of studies now point to the resolution of questions regarding the pathogenesis of PASC.

miR-328-5p functions as a critical negative regulator in early endothelial inflammation and advanced atherosclerosis

Early proatherogenic inflammation constitutes a significant risk factor for atherogenesis development. Despite this, the precise molecular mechanisms driving this pathological progression largely remain elusive. Our study unveils a pivotal role for the microRNA miR-328-5p in dampening endothelial inflammation by modulating the stability of JUNB (JunB proto-oncogene). Perturbation of miR-328-5p levels results in heightened monocyte adhesion to endothelial cells and enhanced transendothelial migration, while its overexpression mitigates these inflammatory processes. Furthermore, miR-328-5p hinders macrophage polarization toward the pro-inflammatory M1 phenotype, and exerts a negative influence on atherosclerotic plaque formation in vivo. By pinpointing JUNB as a direct miR-328-5p target, our research underscores the potential of miR-328-5p as a therapeutic target for inflammatory atherosclerosis. Reintroduction of JUNB effectively counteracts the anti-atherosclerotic effects of miR-328-5p, highlighting the promise of pharmacological miR-328-5p targeting in managing inflammatory atherosclerosis. [BMB Reports 2024; 57(8): 375-380].

Neuroinflammaging: A Tight Line Between Normal Aging and Age-Related Neurodegenerative Disorders

Aging in the healthy brain is characterized by a low-grade, chronic, and sterile inflammatory process known as neuroinflammaging. This condition, mainly consisting in an up-regulation of the inflammatory response at the brain level, contributes to the pathogenesis of age-related neurodegenerative disorders. Development of this proinflammatory state involves the interaction between genetic and environmental factors, able to induce age-related epigenetic modifications. Indeed, the exposure to environmental compounds, drugs, and infections, can contribute to epigenetic modifications of DNA methylome, histone fold proteins, and nucleosome positioning, leading to epigenetic modulation of neuroinflammatory responses. Furthermore, some epigenetic modifiers, which combine and interact during the life course, can contribute to modeling of epigenome dynamics to sustain, or dampen the neuroinflammatory phenotype. The aim of this review is to summarize current knowledge about neuroinflammaging with a particular focus on epigenetic mechanisms underlying the onset and progression of neuroinflammatory cascades in the central nervous system; furthermore, we describe some diagnostic biomarkers that may contribute to increase diagnostic accuracy and help tailor therapeutic strategies in patients with neurodegenerative diseases.

Role of Decreased Expression of miR-155 and miR-146a in Peripheral Blood of Type 2 Diabetes Mellitus Patients with Diabetic Peripheral Neuropathy

Objective

To Study the Correlations of microRNA-155 (miR-155) and microRNA-146a (miR-146a) Expression in Peripheral Blood of Type 2 Diabetes Mellitus (T2DM) Patients with Diabetic Peripheral Neuropathy (DPN), and Explore the Clinical Value of miR-155 and miR-146a in the Diagnosis and Treatment Outcomes of DPN.

Methods

The study included 51 T2DM patients without DPN (T2DM group), 49 T2DM patients with DPN (DPN group), and 50 normal controls (NC group). Quantitative real-time PCR was utilized to determine the expression levels of miR-155 and miR-146a. Clinical features and risk factors for DPN were assessed. Multivariate stepwise logistic regression analysis was conducted to confirm whether the expressions of miR-155 and miR-146a could independently predict the risk of DPN. ROC curve analysis evaluated their diagnostic value.

Results

The T2DM group exhibited significantly lower expression levels of miR-155 and miR-146a compared to the NC group (P < 0.05). Moreover, the DPN group exhibited a significantly decreased expression level of miR-155 and miR-146a compared to the T2DM group (P < 0.01). Multivariate logistic regression analysis indicated that higher levels of miR-155 and miR-146a might serve as protective factors against DPN development. ROC curve analysis revealed that miR-155 (sensitivity 91.8%, specificity 37.3%, AUC 0.641,) and miR-146a (sensitivity 57.1%, specificity 84.3%, AUC 0.722) possess a strong ability to discriminate between T2DM and DPN. Their combined use further enhanced the diagnostic potential of DPN (sensitivity 83.7%, specificity 60.8%, AUC 0.775). A multi-index combination can improve DPN diagnostic efficiency.

Conclusion

The decreased expression of miR-155 and miR-146a in the peripheral blood of T2DM patients is closely related to the occurrence of DPN, highlighting their potential as valuable biomarkers for diagnosing and prognosticating DPN.

Aging aggravates aortic aneurysm and dissection via miR-1204-MYLK signaling axis in mice

The mechanism by which aging induces aortic aneurysm and dissection (AAD) remains unclear. A total of 430 participants were recruited for the screening of differentially expressed plasma microRNAs (miRNAs). We found that miR-1204 is significantly increased in both the plasma and aorta of elder patients with AAD and is positively correlated with age. Cell senescence induces the expression of miR-1204 through p53 interaction with plasmacytoma variant translocation 1, and miR-1204 induces vascular smooth muscle cell (VSMC) senescence to form a positive feedback loop. Furthermore, miR-1204 aggravates angiotensin II-induced AAD formation, and inhibition of miR-1204 attenuates β-aminopropionitrile monofumarate-induced AAD development in mice. Mechanistically, miR-1204 directly targets myosin light chain kinase (MYLK), leading to the acquisition of a senescence-associated secretory phenotype (SASP) by VSMCs and loss of their contractile phenotype. MYLK overexpression reverses miR-1204-induced VSMC senescence, SASP and contractile phenotypic changes, and the decrease of transforming growth factor-β signaling pathway. Our findings suggest that aging aggravates AAD via the miR-1204-MYLK signaling axis.

Aging alone or combined with obesity increases white adipose tissue inflammatory status in male mice

White adipose tissue (WAT) has been recognized as a fundamental and crucial organ of interest in research focusing on inflammation during obesity or aging. WAT is also proposed as a significant component of cholecalciferol and 25-hydroxyvitamin D (25(OH)D) storage, which participates in the decrease of 25(OH)D plasma levels reported during aging and obesity. In the present study, we evaluated WAT and plasma cholecalciferol and 25(OH)D content together with inflammatory status to highlight the putative relationship between vitamin D status and inflammatory process during aging alone or combined with obesity. Circulating cholecalciferol and 25(OH)D and the stored quantity of cholecalciferol and 25(OH)D in WAT were quantified in young and old mice fed a control or obesogenic diet. The inflammation was assessed by measuring plasma inflammatory cytokines, mRNA, and microRNAs inflammatory-associated in WAT. The combination of aging and obesity decreased 25(OH)D plasma levels but did not modify circulating inflammatory markers. A cumulative effect of aging and obesity was observed in WAT, with rising mRNA inflammatory cytokines, notably Ccl5 and Tnf. Interestingly, aging and obesity-associated were also characterized by increased inflammatory microRNA expression. The inflammatory parameters in WAT were negatively correlated with the plasma 25(OH)D but positively correlated with the quantity of cholecalciferol and 25(OH)D in WAT. These results support the cumulative effect of obesity and aging in aggravation of WAT inflammation and suggest that accumulation of cholecalciferol and 25(OH)D in WAT could constitute a mechanism to counteract WAT inflammation during aging and obesity.

Mechanistic and therapeutic perspectives of non-coding RNA-modulated apoptotic signaling in diabetic retinopathy

Diabetic retinopathy (DR), a significant and vision-endangering complication associated with diabetes mellitus, constitutes a substantial portion of acquired instances of preventable blindness. The progression of DR appears to prominently feature the loss of retinal cells, encompassing neural retinal cells, pericytes, and endothelial cells. Therefore, mitigating the apoptosis of retinal cells in DR could potentially enhance the therapeutic approach for managing the condition by suppressing retinal vascular leakage. Recent advancements have highlighted the crucial regulatory roles played by non-coding RNAs (ncRNAs) in diverse biological processes. Recent advancements have highlighted that non-coding RNAs (ncRNAs), including microRNAs (miRNAs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs), act as central regulators in a wide array of biogenesis and biological functions, exerting control over gene expression associated with histogenesis and cellular differentiation within ocular tissues. Abnormal expression and activity of ncRNAs has been linked to the regulation of diverse cellular functions such as apoptosis, and proliferation. This implies a potential involvement of ncRNAs in the development of DR. Notably, ncRNAs and apoptosis exhibit reciprocal regulatory interactions, jointly influencing the destiny of retinal cells. Consequently, a thorough investigation into the complex relationship between apoptosis and ncRNAs is crucial for developing effective therapeutic and preventative strategies for DR. This review provides a fundamental comprehension of the apoptotic signaling pathways associated with DR. It then delves into the mutual relationship between apoptosis and ncRNAs in the context of DR pathogenesis. This study advances our understanding of the pathophysiology of DR and paves the way for the development of novel therapeutic strategies.

miR-146a Decreases Inflammation and ROS Production in Aged Dermal Fibroblasts

Aging is associated with a decline in the functionality of various cell types, including dermal fibroblasts, which play a crucial role in maintaining skin homeostasis and wound healing. Chronic inflammation and increased reactive oxygen species (ROS) production are hallmark features of aging, contributing to impaired wound healing. MicroRNA-146a (miR-146a) has been implicated as a critical regulator of inflammation and oxidative stress in different cell types, yet its role in aged dermal fibroblasts and its potential relevance to wound healing remains poorly understood. We hypothesize that miR-146a is differentially expressed in aged dermal fibroblasts and that overexpression of miR-146a will decrease aging-induced inflammatory responses and ROS production. Primary dermal fibroblasts were isolated from the skin of 17-week-old (young) and 88-week-old (aged) mice. Overexpression of miR-146a was achieved through miR-146a mimic transfection. ROS were detected using a reliable fluorogenic marker, 2,7-dichlorofluorescin diacetate. Real-time PCR was used to quantify relative gene expression. Our investigation revealed a significant reduction in miR-146a expression in aged dermal fibroblasts compared to their younger counterparts. Moreover, aged dermal fibroblasts exhibited heightened levels of inflammatory responses and increased ROS production. Importantly, the overexpression of miR-146a through miR-146a mimic transfection led to a substantial reduction in inflammatory responses through modulation of the NF-kB pathway in aged dermal fibroblasts. Additionally, the overexpression of miR-146a led to a substantial decrease in ROS production, achieved through the downregulation of NOX4 expression in aged dermal fibroblasts. These findings underscore the pivotal role of miR-146a in mitigating both inflammatory responses and ROS production in aged dermal fibroblasts, highlighting its potential as a therapeutic target for addressing age-related skin wound healing.

Mitochondrial microRNAs: New Emerging Players in Vascular Senescence and Atherosclerotic Cardiovascular Disease

MicroRNAs (miRNAs) are small non-coding RNAs that play an important role by controlling gene expression in the cytoplasm in almost all biological pathways. Recently, scientists discovered that miRNAs are also found within mitochondria, the energy-producing organelles of cells. These mitochondrial miRNAs, known as mitomiRs, can originate from the nuclear or mitochondrial genome, and they are pivotal in controlling mitochondrial function and metabolism. New insights indicate that mitomiRs may influence key aspects of the onset and progression of cardiovascular disease, especially concerning mitochondrial function and metabolic regulation. While the importance of mitochondria in cardiovascular health and disease is well-established, our understanding of mitomiRs' specific functions in crucial biological pathways, including energy metabolism, oxidative stress, inflammation, and cell death, is still in its early stages. Through this review, we aimed to delve into the mechanisms of mitomiR generation and their impacts on mitochondrial metabolic pathways within the context of vascular cell aging and atherosclerotic cardiovascular disease. The relatively unexplored field of mitomiR biology holds promise for future research investigations, with the potential to yield novel diagnostic tools and therapeutic interventions.

Metformin improves diabetic neuropathy by reducing inflammation through up-regulating the expression of miR-146a and suppressing oxidative stress

PURPOSE

Diabetic neuropathy (DN) is a notable complication of diabetes mellitus. The potential involvement of miR-146a in DN regulation is presently under investigation. Metformin, a commonly prescribed medication for diabetes, is the primary therapeutic intervention. This study aimed to unveil the potential protective effects of metformin on diabetic neuropathy and explore the mechanisms underlying its action.

METHOD

Six-weeks male Sprague Dawley rats (n = 40) were randomly divided into 5 groups. The rat model of diabetic neuropathy (DN) was established by administering streptozotocin (STZ). To investigate the effects on the sciatic nerve and resident Schwann cells (RSCs), metformin and miR-146a mimics were administered, and our research explored the potential underlying mechanism.

RESULT

The sciatic nerve samples obtained from diabetic rats exhibited noticeable morphological damage, accompanied by decreased miR-146a expression (2.61 ± 0.11 vs 5.0 ± 0.3, p < 0.01) and increased inflammation levels (p65: 1.89 ± 0.04 vs 0.82 ± 0.05, p < 0.01; TNF-α: 0.93 ± 0.03 vs 0.33 ± 0.03, p < 0.01). Notably, the administration of metformin effectively ameliorated the structural alterations in the sciatic nerve by suppressing the inflammatory pathway (p65: 1.15 ± 0.05 vs 1.89 ± 0.04, p < 0.01; TNF-α: 0.67 ± 0.04 vs 0.93 ± 0.03, p < 0.01) and reducing oxidative stress (NO: 0.062 ± 0.004 vs 0.154 ± 0.004umol/mg, p < 0.01; SOD: 3.08 ± 0.09 vs 2.46 ± 0.09 U/mg, p < 0.01). The miR-146a mimics intervention group exhibited comparable findings.

CONCLUSION

This study's findings implied that metformin can potentially mitigate diabetic neuropathy in rats through the modulation of miR-146a expression.

miR-21-Mediated Endothelial Senescence and Dysfunction Are Involved in Cigarette Smoke-Induced Pulmonary Hypertension through Activation of PI3K/AKT/mTOR Signaling

Smoking is a pathogenic factor for pulmonary hypertension (PH). Our previous study showed that serum miR-21 levels are elevated in smokers. miR-21 is considered as engaged in the PH process; however, its mechanisms remain unclear. In this investigation, we found that in the lung tissue of smoking-induced PH patients, the levels of miR-21 and aging markers (p21 and p16) were upregulated, and the function of pulmonary vascular endothelial cells was also impaired. Exposure of mice to cigarette smoke (CS) for four months caused similar changes in lung tissues and increased pulmonary arterial pressure, which were attenuated by knockout of miR-21. Further, human umbilical vein endothelial cells (HUVECs) exposed to cigarette smoke extract (CSE) revealed upregulation of miR-21 levels, depression of PTEN, activation of PI3K/AKT/mTOR signaling, an increase in senescence indexes, and enhanced dysfunction. Inhibiting miR-21 overexpression reversed the PTEN-mTOR signaling pathway and prevented senescence and dysfunction of HUVECs. In sum, our data indicate that miR-21-mediated endothelial senescence and dysfunction are involved in CS-induced PH through the activation of PI3K/AKT/mTOR signaling, which suggests that selective miR-21 inhibition offers the potential to attenuate PH.

XIST and MUC1-C form an auto-regulatory pathway in driving cancer progression

The long non-coding RNA X-inactive specific transcript (lncRNA XIST) and MUC1 gene are dysregulated in chronic inflammation and cancer; however, there is no known interaction of their functions. The present studies demonstrate that MUC1-C regulates XIST lncRNA levels by suppressing the RBM15/B, WTAP and METTL3/14 components of the m6A methylation complex that associate with XIST A repeats. MUC1-C also suppresses the YTHDF2-CNOT1 deadenylase complex that recognizes m6A sites and contributes to XIST decay with increases in XIST stability and expression. In support of an auto-regulatory pathway, we show that XIST regulates MUC1-C expression by promoting NF-κB-mediated activation of the MUC1 gene. Of significance, MUC1-C and XIST regulate common genes associated with inflammation and stemness, including (i) miR-21 which is upregulated across pan-cancers, and (ii) TDP-43 which associates with the XIST E repeats. Our results further demonstrate that the MUC1-C/XIST pathway (i) is regulated by TDP-43, (ii) drives stemness-associated genes, and (iii) is necessary for self-renewal capacity. These findings indicate that the MUC1-C/XIST auto-regulatory axis is of importance in cancer progression.

miR-186-5p improves alveolar epithelial barrier function by targeting the wnt5a/β-catenin signaling pathway in sepsis-acute lung injury

BACKGROUND

Alveolar epithelial barrier dysfunction is one of the pathological features of sepsis-acute lung injury(ALI). However, the molecular mechanisms that regulate the function of alveolar epithelial barrier remain unclear. This study aimed to determine the regulatory role of miR-186-5p in alveolar epithelial barrier function in sepsis-ALI and its underlying molecular mechanism.

METHODS

We established sepsis-ALI models in vivo and in vitro, detected the miR-186-5p and wnt5a/β-catenin expressions, and observed the functional changes of the alveolar epithelial barrier by miR-186-5p overexpression. We used rescue experiments to clarify whether miR-186-5p works through wnt5a/β-catenin.

RESULTS

miR-186-5p expression was decreased, wnt5a expression was increased, and the wnt5a/β-catenin signaling pathway was activated in mouse lung tissues and A549 cells after inflammatory stimulation. miR-186-5p overexpression resulted in wnt5a/β-catenin signaling pathway inhibition, decreased apoptosis in A549 cells, improved alveolar epithelial barrier function, reduced lung tissue injury in ALI mice, decreased IL-6 and TNF-α levels, and increased claudin4 and ZO-1 expression. Using miRNA-related database prediction and dual-luciferase reporter gene analysis, the targeting relationship between miR-186-5p and wnt5a was determined. The protective effect produced by miR-186-5p overexpression on the alveolar barrier was reversed after the application of the wnt5a/β-catenin activator Licl.

CONCLUSION

Our experimental data suggest miR-186-5p targets the wnt5a/β-catenin pathway, thereby regulating alveolar epithelial barrier function. Furthermore, both miR-186-5p and wnt5a/β-catenin are potential therapeutic targets that could impact sepsis-ALI.

MicroRNA Regulatory Pattern in Diabetic Mouse Cortex at Different Stages Following Ischemic Stroke

After ischemic stroke, microRNAs (miRNAs) participate in various processes, including immune responses, inflammation, and angiogenesis. Diabetes is a key factor increasing the risk of ischemic stroke; however, the regulatory pattern of miRNAs at different stages of diabetic stroke remains unclear. This study comprehensively analyzed the miRNA expression profiles in diabetic mice at 1, 3, and 7 days post-reperfusion following the middle cerebral artery occlusion (MCAO). We identified differentially expressed (DE) miRNAs in diabetic stroke and found significant dysregulation of some novel miRNAs (novel_mir310, novel_mir89, and novel_mir396) post-stroke. These DEmiRNAs were involved in apoptosis and the formation of tight junctions. Finally, we identified three groups of time-dependent DE miRNAs (miR-6240, miR-135b-3p, and miR-672-5p). These have the potential to serve as biomarkers of diabetic stroke. These findings provide a new perspective for future research, emphasizing the dynamic changes in miRNA expression after diabetic stroke and offering potential candidates as biomarkers for future clinical applications.

Restoration of epigenetic impairment in the skeletal muscle and chronic inflammation resolution as a therapeutic approach in sarcopenia

Sarcopenia is an age-associated loss of skeletal muscle mass, strength, and function, accompanied by severe adverse health outcomes, such as falls and fractures, functional decline, high health costs, and mortality. Hence, its prevention and treatment have become increasingly urgent. However, despite the wide prevalence and extensive research on sarcopenia, no FDA-approved disease-modifying drugs exist. This is probably due to a poor understanding of the mechanisms underlying its pathophysiology. Recent evidence demonstrate that sarcopenia development is characterized by two key elements: (i) epigenetic dysregulation of multiple molecular pathways associated with sarcopenia pathogenesis, such as protein remodeling, insulin resistance, mitochondria impairments, and (ii) the creation of a systemic, chronic, low-grade inflammation (SCLGI). In this review, we focus on the epigenetic regulators that have been implicated in skeletal muscle deterioration, their individual roles, and possible crosstalk. We also discuss epidrugs, which are the pharmaceuticals with the potential to restore the epigenetic mechanisms deregulated in sarcopenia. In addition, we discuss the mechanisms underlying failed SCLGI resolution in sarcopenia and the potential application of pro-resolving molecules, comprising specialized pro-resolving mediators (SPMs) and their stable mimetics and receptor agonists. These compounds, as well as epidrugs, reveal beneficial effects in preclinical studies related to sarcopenia. Based on these encouraging observations, we propose the combination of epidrugs with SCLI-resolving agents as a new therapeutic approach for sarcopenia that can effectively attenuate of its manifestations.

Low circulating levels of miR-17 and miR-126-3p are associated with increased mortality risk in geriatric hospitalized patients affected by cardiovascular multimorbidity

MultiMorbidity (MM), defined as the co-occurrence of two or more chronic conditions, is associated with poorer health outcomes, such as recurrent hospital readmission and mortality. As a group of conditions, cardiovascular disease (CVD) exemplifies several challenges of MM, and the identification of prognostic minimally invasive biomarkers to stratify mortality risk in patients affected by cardiovascular MM is a huge challenge. Circulating miRNAs associated to inflammaging and endothelial dysfunction, such as miR-17, miR-21-5p, and miR-126-3p, are expected to have prognostic relevance. We analyzed a composite profile of circulating biomarkers, including miR-17, miR-21-5p, and miR-126-3p, and routine laboratory biomarkers in a sample of 246 hospitalized geriatric patients selected for cardiovascular MM from the Report-AGE INRCA database and BioGER INRCA biobank, to evaluate the association with all-cause mortality during 31 days and 12 and 24 months follow-up. Circulating levels of miR-17, miR-126-3p, and some blood parameters, including neutrophil to lymphocyte ratio (NLR) and eGFR, were significantly associated with mortality in these patients. Overall, our results suggest that in a cohort of geriatric hospitalized patients affected by cardiovascular MM, lower circulating miR-17 and miR-126-3p levels could contribute to identify patients at higher risk of short- and medium-term mortality.

The Molecular Mechanisms in Senescent Cells Induced by Natural Aging and Ionizing Radiation

This review discusses the relationship between cellular senescence and radiation exposure. Given the wide range of ionizing radiation sources encountered by people in professional and medical spheres, as well as the influence of natural background radiation, the question of the effect of radiation on biological processes, particularly on aging processes, remains highly relevant. The parallel relationship between natural and radiation-induced cellular senescence reveals the common aspects underlying these processes. Based on recent scientific data, the key points of the effects of ionizing radiation on cellular processes associated with aging, such as genome instability, mitochondrial dysfunction, altered expression of miRNAs, epigenetic profile, and manifestation of the senescence-associated secretory phenotype (SASP), are discussed. Unraveling the molecular mechanisms of cellular senescence can make a valuable contribution to the understanding of the molecular genetic basis of age-associated diseases in the context of environmental exposure.

Regulatory RNAs in immunosenescence

BACKGROUND

Immunosenescence is a multifactorial stress response to different intrinsic and extrinsic insults that cause immune deterioration and is accompanied by genomic or epigenomic perturbations. It is now widely recognized that genes and proteins contributing in the process of immunosenescence are regulated by various noncoding (nc) RNAs, including microRNAs (miRNAs), long ncRNAs, and circular RNAs.

AIMS

This review article aimed to evaluate the regulatore RNAs roles in the process of immunosenescence.

METHODS

We analyzed publications that were focusing on the different roles of regulatory RNAs on the several aspects of immunosenescence.

RESULTS

In the immunosenescence setting, ncRNAs have been found to play regulatory roles at both transcriptional and post-transcriptional levels. These factors cooperate to regulate the initiation of gene expression programs and sustaining the senescence phenotype and proinflammatory responses.

CONCLUSION

Immunosenescence is a complex process with pivotal alterations in immune function occurring with age. The extensive network that drive immunosenescence-related features are are mainly directed by a variety of regulatory RNAs such as miRNAs, lncRNAs, and circRNAs. Latest findings about regulation of senescence by ncRNAs in the innate and adaptive immune cells as well as their role in the immunosenescence pathways, provide a better understanding of regulatory RNAs function in the process of immunosenescence.

Inhibition of miR-143-3p Restores Blood-Testis Barrier Function and Ameliorates Sertoli Cell Senescence

Due to the increasing trend of delayed childbirth, the age-related decline in male reproductive function has become a widely recognized issue. Sertoli cells (SCs) play a vital role in creating the necessary microenvironment for spermatogenesis in the testis. However, the mechanism underlying Sertoli cell aging is still unclear. In this study, senescent Sertoli cells showed a substantial upregulation of miR-143-3p expression. miR-143-3p was found to limit Sertoli cell proliferation, promote cellular senescence, and cause blood-testis barrier (BTB) dysfunction by targeting ubiquitin-conjugating enzyme E2 E3 (UBE2E3). Additionally, the TGF-β receptor inhibitor SB431542 showed potential in alleviating age-related BTB dysfunction, rescuing testicular atrophy, and reversing the reduction in germ cell numbers by negatively regulating miR-143-3p. These findings clarified the regulatory pathways underlying Sertoli cell senescence and suggested a promising therapeutic approach to restore BTB function, alleviate Sertoli cell senescence, and improve reproductive outcomes for individuals facing fertility challenges.

Pterostilbene alleviates abdominal aortic aneurysm via inhibiting macrophage pyroptosis by activating the miR-146a-5p/TRAF6 axis

Pterostilbene (PTE), a natural stilbene found in blueberries and several varieties of grapes, has several pharmacological activities, including anti-inflammatory and antioxidative activities. However, its role in abdominal aortic aneurysm (AAA), which is a severe inflammatory vascular disease, remains incompletely understood. In this study, we investigated the protective effects of natural stilbene PTE on AAA formation and the underlying mechanism. Two AAA mouse models (Ang II-induced model and PPE-induced model) were used to examine the effect of PTE on AAA formation. We showed that PTE administration attenuated AAA formation in mice. Furthermore, we found that PTE significantly inhibited inflammatory responses in mouse aortas, as PTE suppressed macrophage pyroptosis and prevented macrophage infiltration in aortas, resulting in reduced expression of pro-inflammatory cytokines in aortas. We also observed similar results in LPS + ATP-treated Raw 264.7 cells (a macrophage cell line) and primary peritoneal macrophages in vitro. We showed that pretreatment with PTE restrained inflammatory responses in macrophages by inhibiting macrophage pyroptosis. Mechanistically, miR-146a-5p and TRAF6 interventions in vivo and in vitro were used to investigate the role of the miR-146a-5p/TRAF6 axis in the beneficial effect of PTE on macrophage pyroptosis and AAA. We found that PTE inhibited macrophage pyroptosis by miR-146a-5p-mediated suppression of downstream TRAF6 expression. Moreover, miR-146a-5p knockout or TRAF6 overexpression abrogated the protective effect of PTE on macrophage pyroptosis and AAA formation. These findings suggest that miR-146a-5p/TRAF6 axis activation by PTE protects against macrophage pyroptosis and AAA formation. PTE might be a promising agent for preventing inflammatory vascular diseases, including AAA.

miR-146a regulates emphysema formation and abnormal inflammation in the lungs of two mouse models

miR-146a, a microRNA (miRNA) that regulates inflammatory responses, plays an important role in many inflammatory diseases. Although an in vitro study had suggested that miR-146a is involved in abnormal inflammatory response, being a critical factor in the pathogenesis of chronic obstructive pulmonary disease (COPD), in vivo evidence of its pathogenic role in COPD remains limited. Eight-week-old male B6(FVB)-Mir146tm1.1Bal/J [miR-146a knockout (KO)] and C57BL/6J mice were intratracheally administered elastase and evaluated after 28 days or exposed to cigarette smoke (CS) and evaluated after 5 mo. miR-146a expression was significantly increased in C57BL/6J mouse lungs due to elastase administration (P = 0.027) or CS exposure (P = 0.019) compared with that in the control group. Compared with C57BL/6J mice, elastase-administered miR-146a-KO mice had lower average computed tomography (CT) values (P = 0.017) and increased lung volume-to-weight ratio (P = 0.016), mean linear intercept (P < 0.001), and destructive index (P < 0.001). Moreover, total cell (P = 0.006), macrophage (P = 0.001), neutrophil (P = 0.026), chemokine (C-X-C motif) ligand 2/macrophage inflammatory protein-2 [P = 0.045; in bronchoalveolar lavage fluid (BALF)], cyclooxygenase-2, and matrix metalloproteinase-2 levels were all increased (in the lungs). Following long-term CS exposure, miR-146a-KO mice showed a greater degree of emphysema formation in their lungs and inflammatory response in the BALF and lungs than C57BL/6J mice. Collectively, miR-146a protected against emphysema formation and the associated abnormal inflammatory response in two murine models.NEW & NOTEWORTHY This study demonstrates that miR-146a expression is upregulated in mouse lungs because of elastase- and CS-induced emphysema and that the inflammatory response by elastase or CS is enhanced in the lungs of miR-146a-KO mice than in those of control mice, resulting in the promotion of emphysema. This is the first study to evaluate the protective role of miR-146a in emphysema formation and the associated abnormal inflammatory response in different in vivo models.

MicroRNA-146b protects kidney injury during urinary tract infections by modulating macrophage polarization

IMPORTANCE

Kidney injury during acute urinary tract infections (UTIs) caused by uropathogenic Escherichia coli (UPEC) is an important public health problem. However, how kidney injury develops during UPEC infection is still unclear. Although antibiotic therapy is currently an effective treatment for UTI, it cannot avoid kidney injury. MicroRNAs have gained extensive attention as essential molecules capable of regulating the autoimmune response. Among these, microRNA-146b (miR-146b) is involved in regulating inflammatory responses. In the present study, we demonstrated that miR-146b played an essential role in the development of kidney injury during UTIs caused by UPEC. The results showed that miR-146b may suppress M1 macrophage polarization and alleviate acute kidney injury. Furthermore, the miR-146b activator, agomir, in order to upregulate miR-146b, was effective in treating kidney damage by inhibiting the activation of M1 macrophages. In conclusion, our findings elucidated the mechanisms by which miR-146b alleviated kidney injury induced by UTIs, shed new light on the relationship between microRNA and bacterial infection, and provided a novel therapeutic target for treating this common bacterial infection.