A guide to miRNAs in inflammation and innate immune responses

Serum microRNA-125b-5p expression in patients with dilated cardiomyopathy combined with heart failure and its effect on myocardial fibrosis

OBJECTIVE

This paper was performed to decipher the serum microRNA (miR)-125b-5p expression in patients with dilated cardiomyopathy (DCM) combined with heart failure (HF) and its effect on myocardial fibrosis.

METHODS

Serum miR-125b-5p expression, LVEDD, LVESD, LVEF, LVFS, and NT-proBNP levels were evaluated in clinical samples. A rat DCM model was established by continuous intraperitoneal injection of adriamycin and treated with miR-125b-5p agomir and its negative control. Cardiac function, serum TNF-α, hs-CRP, and NT-proBNP levels, pathological changes in myocardial tissues, cardiomyocyte apoptosis, and the expression levels of miR-125b-5p and fibrosis-related factors were detected in rats.

RESULTS

In comparison to the control group, the case group had higher levels of LVEDD, LVESD, and NT-pro-BNP, and lower levels of LVEF, LVFS, and miR-125b-5p expression levels. Overexpression of miR-125b-5p effectively led to the improvement of cardiomyocyte hypertrophy and collagen arrangement disorder in DCM rats, the reduction of blue-stained collagen fibers in the interstitial myocardium, the reduction of the levels of TNF-α, hs-CRP, and NT-proBNP and the expression levels of TGF-1β, Collagen I, and α-SMA, and the reduction of the number of apoptosis in cardiomyocytes.

CONCLUSION

Overexpression of miR-125b-5p is effective in ameliorating myocardial fibrosis.

The Involvement of miR-221/222 in Vascular Pathophysiology: Implications for Stenting

MicroRNAs (miRNAs) are pivotal regulatory molecules involved in numerous cellular processes, including apoptosis, differentiation, proliferation, and migration. Recent research highlights specific miRNAs, such as the miR-221/222 cluster, which modulate key signaling pathways related to vascular smooth muscle cell (VSMC) proliferation, inflammation, and endothelial function. This function of miR-221/222 is accompanied by influencing the expression of certain proteins implicated in VSMCs and endothelial cells regulatory processes. miRNAs have been increasingly recognized for their roles in cardiovascular diseases, particularly in the mechanisms underlying in-stent restenosis and stent thrombosis. Elevated levels of miR-221/222 have been reported to be associated with severe adverse events following stenting and affect VSMC behavior and inflammatory responses. This image makes them promising candidates for new therapeutic strategies to address the most complex inferences of stenting, in-stent restenosis/stent thrombosis. Therefore, a discussion over the involvement of miR-221/222 in vascular pathophysiology could lead to finding possible signaling pathways and better stent designing for improving outcomes in patients undergoing stenting. Emerging therapeutic approaches, such as anti-miR oligonucleotides, offer the potential for translating these findings into clinical practice. This review article systematically investigates the biogenesis and functions of the miR-221/222 cluster along with its contributions to angiogenesis, vascular calcification, and neointimal formation. It aims to provide readers and researchers with insights into the signaling pathways that underpin vascular pathology linked to the miR-221 and miR-222 involvement.

Role of miRNAs in neurovascular injury and repair

MicroRNAs (miRNA) are endogenously produced small, non-coded, single-stranded RNAs. Due to their involvement in various cellular processes and cross-communication with extracellular components, miRNAs are often coined the "grand managers" of the cell. miRNAs are frequently involved in upregulation as well as downregulation of specific gene expression and thus, are often found to play a vital role in the pathogenesis of multiple diseases. Central nervous system (CNS) diseases prove fatal due to the intricate nature of both their development and the methods used for treatment. A considerable amount of ongoing research aims to delineate the complex relationships between miRNAs and different diseases, including each of the neurological disorders discussed in the present review. Ongoing research suggests that specific miRNAs can play either a pathologic or restorative and/or protective role in various CNS diseases. Understanding how these miRNAs are involved in various regulatory processes of CNS such as neuroinflammation, neurovasculature, immune response, blood-brain barrier (BBB) integrity and angiogenesis is of empirical importance for developing effective therapies. Here in this review, we summarized the current state of knowledge of miRNAs and their roles in CNS diseases along with a focus on their association with neuroinflammation, innate immunity, neurovascular function and BBB.

MicroRNAs Regulate the Expression of Genes Related to the Innate Immune and Inflammatory Response in Rabbits Infected with Lagovirus europaeus GI.1 and GI.2 Genotypes

MicroRNAs (miR) are a group of small, non-coding RNAs of 17-25 nucleotides that regulate gene expression at the post-transcriptional level. Dysregulation of miRNA expression or function may contribute to abnormal gene expression and signaling pathways, leading to disease pathology. Lagovirus europaeus (L. europaeus) causes severe disease in rabbits called rabbit hemorrhagic disease (RHD). The symptoms of liver, lung, kidney, and spleen degeneration observed during RHD are similar to those of acute liver failure (ALF) and multi-organ failure (MOF) in humans. In this study, we assessed the expression of miRs and their target genes involved in the innate immune and inflammatory response. Also, we assessed their potential impact on pathways in L. europaeus infection-two genotypes (GI.1 and GI.2)-in the liver, lungs, kidneys, and spleen. The expression of miRs and target genes was determined using quantitative real-time PCR (qPCR). We assessed the expression of miR-155 (MyD88, TAB2, p65, NLRP3), miR-146a (IRAK1, TRAF6), miR-223 (TLR4, IKKα, NLRP3), and miR-125b (MyD88). We also examined biomarkers of inflammation: IL-1β, IL-6, TNF-α, and IL-18 in four tissues at the mRNA level. Our study shows that the main regulators of the innate immune and inflammatory response in L. europaeus/GI.1 and GI.2 infection, as well as RHD, are miR-155, miR-223, and miR-146a. During infection with L. europaeus/RHD, miR-155 has both pro- and anti-inflammatory effects in the liver and anti-inflammatory effects in the kidneys and spleen; miR-146a has anti-inflammatory effects in the liver, lungs and kidneys; miR-223 has anti-inflammatory effects in all tissues; however, miR-125b has anti-inflammatory effects only in the liver. In each case, such an effect may be a determinant of the pathogenesis of RHD. Our research shows that miRs may regulate three innate immune and inflammatory response pathways in L. europaeus infection. However, the result of this regulation may be influenced by the tissue microenvironment. Our research shows that infection of rabbits with L. europaeus/GI.1 and GI.2 genotypes causes an overexpression of two critical acute phase cytokines: IL-6 in all examined tissues and TNF-α (in the liver, lungs, and spleen). IL-1β was highly expressed only in the lungs after L. europaeus infection. These facts indicate a strong and rapid involvement of the local innate immune and inflammatory response in L. europaeus infection-two genotypes (GI.1 and GI.2)-and in the pathogenesis of RHD. Profile of biomarkers of inflammation in rabbits infected with L. europaeus/GI.1 and GI.2 genotypes are similar regarding the nature of changes but are different for individual tissues. Therefore, we propose three inflammation profiles for L. europaeus infection for both GI.1 and GI.2 genotypes (pulmonary, renal, liver, and spleen).

MicroRNAs Modulating Neuroinflammation in Parkinson's disease

Parkinson's disease (PD) is one of the most frequent age-associated neurodegenerative disorder. Presence of α-synuclein-containing aggregates in the substantia nigra pars compacta (SNpc) and loss of dopaminergic (DA) neurons are among the characteristic of PD. One of the hallmarks of PD pathophysiology is chronic neuroinflammation. Activation of glial cells and elevated levels of pro-inflammatory factors are confirmed as frequent features of the PD brain. Chronic secretion of pro-inflammatory cytokines by activated astrocytes and microglia exacerbates DA neuron degeneration in the SNpc. MicroRNAs (miRNAs) are among endogenous non-coding small RNA with the ability to perform post-transcriptional regulation in target genes. In that regard, the capability of miRNAs for modulating inflammatory signaling is the center of attention in many investigations. MiRNAs could enhance or limit inflammatory signaling, exacerbating or ameliorating the pathological consequences of extreme neuroinflammation. This review summarizes the importance of inflammation in the pathophysiology of PD. Besides, we discuss the role of miRNAs in promoting or protecting neural cell injury in the PD model by controlling the inflammatory pathway. Modifying the neuroinflammation by miRNAs could be considered a primary therapeutic strategy for PD.

Paeonol attenuated high glucose-induced apoptosis via up-regulating miR-223-3p in mouse cardiac microvascular endothelial cells

To investigate the role of miR-223-3p in the modulatory effect of paeonol (Pae) on high glucose (HG)-induced endothelial cell apoptosis. HG (25 mmol/L) was used to induce cellular damage and apoptosis in the mouse cardiac microvascular endothelial cells (MCMECs). Various concentration of Pae was tested and 60 μmol/L Pae was selected for the subsequent studies. MCMECs were transfected with exogenous miR-223-3p mimics or anti-miR-223-3p inhibitors. Cell viability was assessed by MTT assay and apoptosis was quantified by flow cytometry. The expression of miR-223-3p and NLRP3 mRNA was measured using real-time quantitative RT-PCR, and protein level of NLRP3 and apoptosis-related proteins was detected by immunoblotting. Pae significantly attenuated HG-induced apoptosis of MCMECs in a concentration-dependent manner. In addition, Pae (60 µmol/L) significantly reversed HG-induced down-regulation of miR-223-3p and up-regulation of NLRP3. Pae (60 µmol/L) also significantly blocked HG-induced up-regulation of Bax and Caspase-3 as well as down-regulation of Bcl-2. Moreover, exogenous miR-223-3p mimics not only significantly attenuated HG-induced apoptosis, but also significantly suppressed NRLP-3 and pro-apoptotic proteins in the MCMECs. In contrast, transfection of exogenous miR-223-3p inhibitors into the MCMECs resulted in not only significantly increased apoptosis of the cells, but also significant suppression of NLRP3 and pro-apoptotic proteins in the cells. Pae attenuated HG-induced apoptosis of MCMECs in a concentration-dependent manner. MiR-223-3p may mediate the modulatory effects of Pae on MCMEC survival or apoptosis through targeting NLRP3 and regulating apoptosis-associated proteins.

Circulating extracellular vesicles and small non-coding RNAs cargo in idiopathic inflammatory myopathies reveal differences across myositis subsets

OBJECTIVE

To investigate the epigenetic footprint of idiopathic inflammatory myopathies (IIM) through characterization of circulating extracellular vesicles (EVs) and the expression of EV-derived small non-coding RNAs (sncRNAs).

METHODS

In this cross-sectional study, EVs were isolated by size-exclusion chromatography from plasma of patients with IIM and age- and sex-matched healthy donors (HD). EV-derived sncRNAs were sequenced and quantified using Next-Generation Sequencing (NGS). Following quality control and normalization, filtered count reads were used for differential microRNA (miRNA) and piwi-interacting RNA (piRNA) expression analyses. Putative gene targets enriched for pathways implicated in IIM were analyzed. Patients' clinical and laboratory characteristics at the time of sampling were recorded.

RESULTS

Forty-seven IIM patients and 45 HD were enrolled. MiR-486-5p (p < 0.01), miR-122-5p, miR-192-5p, and miR-32-5p were significantly upregulated (p < 0.05 for all), while miR-142-3p (p < 0.001), miR-141-3p (p < 0.01), let-7a-5p (p < 0.05) and miR-3613-5p (p < 0.05) downregulated in EVs from IIM patients versus HD. MiR-486-5p was associated with raised muscle enzymes levels. Several target genes of up/downregulated miRNAs in IIM participate in inflammation, necroptosis, interferon and immune signaling. Six piRNAs were significantly dysregulated in IIM EVs versus HD (p < 0.05). Within IIM, miR-335-5p was selectively upregulated and miR-27a-5p downregulated in dermatomyositis (n = 21, p < 0.01). Finally, plasma EV levels were significantly increased in cancer-associated myositis (CAM, n = 12) versus non-CAM IIM (n = 35, p = 0.02) and HD (p < 0.01). EVs cargo in CAM was significantly enriched of let-7f-5p and depleted of miR-143-3p.

CONCLUSION

Through an unbiased screening of EV-derived sncRNAs, we characterize miRNAs and piRNAs in the EVs cargo as potential biomarkers and modifiers of diverse IIM phenotypes.

Regulation of immune responses to infection through interaction between stem cell-derived exosomes and toll-like receptors mediated by microRNA cargoes

Infectious diseases are among the factors that account for a significant proportion of disease-related deaths worldwide. The primary treatment approach to combat microbial infections is the use of antibiotics. However, the widespread use of these drugs over the past two decades has led to the emergence of resistant microbial species, making the control of microbial infections a serious challenge. One of the most important solutions in the field of combating infectious diseases is the regulation of the host's defense system. Toll-like receptors (TLRs) play a crucial role in the first primary defense against pathogens by identifying harmful endogenous molecules released from dying cells and damaged tissues as well as invading microbial agents. Therefore, they play an important role in communicating and regulating innate and adaptive immunity. Of course, excessive activation of TLRs can lead to disruption of immune homeostasis and increase the risk of inflammatory reactions. Targeting TLR signaling pathways has emerged as a new therapeutic approach for infectious diseases based on host-directed therapy (HDT). In recent years, stem cell-derived exosomes have received significant attention as factors regulating the immune system. The regulation effects of exosomes on the immune system are based on the HDT strategy, which is due to their cargoes. In general, the mechanism of action of stem cell-derived exosomes in HDT is by regulating and modulating immunity, promoting tissue regeneration, and reducing host toxicity. One of their most important cargoes is microRNAs, which have been shown to play a significant role in regulating immunity through TLRs. This review investigates the therapeutic properties of stem cell-derived exosomes in combating infections through the interaction between exosomal microRNAs and Toll-like receptors.

Monocytes and macrophages: Origin, homing, differentiation, and functionality during inflammation

Monocytes and macrophages are essential components of innate immune system and have versatile roles in homeostasis and immunity. These phenotypically distinguishable mononuclear phagocytes play distinct roles in different stages, contributing to the pathophysiology in various forms making them a potentially attractive therapeutic target in inflammatory conditions. Several pieces of evidence have supported the role of different cell surface receptors expressed on these cells and their downstream signaling molecules in initiating and perpetuating the inflammatory response. In this review, we discuss the current understanding of the monocyte and macrophage biology in inflammation, highlighting the role of chemoattractants, inflammasomes, and integrins in the function of monocytes and macrophages during events of inflammation. This review also covers the recent therapeutic interventions targeting these mononuclear phagocytes at the cellular and molecular levels.

Polygonum cillinerve polysaccharide inhibits transmissible gastroenteritis virus by regulating microRNA-181

Transmissible gastroenteritis virus (TGEV) is an important pathogen capable of altering the expression profile of cellular miRNA. In this study, the potential of Polygonum cillinerve polysaccharide (PCP) to treat TGEV-infected piglets was evaluated through in vivo experiments. High-throughput sequencing technology was employed to identify 9 up-regulated and 17 down-regulated miRNAs during PCP-mediated inhibition of TGEV infection in PK15 cells. Additionally, miR-181 was found to be associated with target genes of key proteins in the apoptosis pathway. PK15 cells were treated with various concentrations of PCP following transfection with miR-181 mimic or inhibitor. Real-time PCR assessed the impact on TGEV replication, while electron microscopy (TEM) and Hoechst fluorescence staining evaluated cellular functionality. Western blot analysis was utilized to assess the expression of key signaling factors-cytochrome C (cyt C), caspase 9, and P53-in the apoptotic signaling pathway. The results showed that compared with the control group, 250 μg/mL PCP significantly inhibited TGEV gRNA replication and gene N expression (P < 0.01). Microscopic examination revealed uniform cell morphology and fewer floating cells in PCP-treated groups (250 and 125 μg/mL). TEM analysis showed no typical virus structure in the 250 μg/mL PCP group, and apoptosis staining indicated a significant reduction in apoptotic cells at this concentration. Furthermore, PCP may inhibit TGEV-induced apoptosis via the Caspase-dependent mitochondrial pathway following miR-181 transfection. These findings provide a theoretical basis for further exploration into the mechanism of PCP's anti-TGEV properties.

The Effect of Akkermansia muciniphila and Its Outer Membrane Vesicles on MicroRNAs Expression of Inflammatory and Anti-inflammatory Pathways in Human Dendritic Cells

Probiotics play a crucial role in immunomodulation by regulating dendritic cell (DC) maturation and inducing tolerogenic DCs. Akkermansia muciniphila affects inflammatory response by elevating inhibitory cytokines. We aimed to evaluate whether Akkermansia muciniphila and its outer membrane vesicles (OMVs) affect microRNA-155, microRNA-146a, microRNA-34a, and let-7i expression of inflammatory and anti-inflammatory pathways. Peripheral blood mononuclear cells (PBMCs) were isolated from the healthy volunteers. To produce DCs, monocytes were cultivated with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). DCs were allocated into six subgroups: DC + Lipopolysaccharide (LPS), DC + dexamethasone, DC + A. muciniphila (MOI 100, 50), DC + OMVs (50 µg/ml), and DC + PBS. The surface expression of human leukocyte antigen-antigen D related (HLA-DR), CD86, CD80, CD83, CD11c, and CD14 was examined using flow cytometry, and the expression of microRNAs was assessed using qRT-PCR, and the levels of IL-12 and IL-10 were measured using ELISA. A. muciniphila (MOIs 50, 100) could significantly decrease IL-12 levels relative to the LPS group. The IL-10 levels were decreased in the DC + LPS group than the DC + dexamethasone group. Treatment with A. muciniphila (MOI 100) and OMVs could elevate the concentrations of IL-10. DC treatment with LPS led to a significant increment in the expression of microRNA-155, microRNA-34a, and microRNA-146a. The expression of these microRNAs was reversed by A. muciniphilia and its OMVs treatment. Let-7i increased in treatment groups compared to the DC + LPS group. A. muciniphilia (MOI 50) had a substantial effect on the expression of HLA-DR, CD80, and CD83 on DCs. Therefore, DCs treatment with A. muciniphila led to induce tolerogenic DCs and the production of anti-inflammatory IL-10.

MicroRNA-mediated epigenetic regulation of inflammasomes in inflammatory responses and immunopathologies

Inflammation represents the first-line defense mechanism of the host against pathogens and cellular stress. One of the most critical inflammatory responses is characterized by the activation of inflammasomes, intracellular multiprotein complexes that induce inflammatory signaling pathways in response to various pathogen-associated molecular patterns or danger-associated molecular patterns under physiological and pathological conditions. Inflammasomes are tightly regulated in normal cells, and dysregulation of these complexes is observed in various pathological conditions, especially inflammatory diseases and cancers. Epigenetic regulation has been suggested as a key mechanism in modulating inflammasome activity, and microRNAs (miRNAs) have been implicated in the post-transcriptional regulation of inflammasomes. Therefore, miRNA-mediated epigenetic regulation of inflammasomes in pathological conditions has received considerable attention, and current strategies for targeting inflammasomes have been shown to be effective in the treatment of diseases associated with inflammasome activation. This review summarizes recent studies suggesting the roles of miRNAs in the epigenetic control of inflammasomes and highlights the potential of miRNAs as a therapeutic tool for treating human diseases.

MicroRNAs: Key modulators of inflammation-associated diseases

Inflammation is a multifaceted biological and pathophysiological response to injuries, infections, toxins, and inflammatory mechanisms that plays a central role in the progression of various diseases. MicroRNAs (miRNAs) are tiny, 19-25 nucleotides long, non-coding RNAs that regulate gene expression via post-transcriptional repression. In this review, we highlight the recent findings related to the significant roles of miRNAs in regulating various inflammatory cascades and immunological processes in the context of many lifestyle-related diseases such as diabetes, cardiovascular diseases, cancer, etc. We also converse on how miRNAs can have a dual impact on inflammatory responses, suggesting that regulation of their functions for therapeutic purposes may be disease-specific.

MicroRNA-146a gene transfer ameliorates senescence and senescence-associated secretory phenotypes in tendinopathic tenocytes

OBJECTIVE

Tendinopathy is influenced by multiple factors, including chronic inflammation and aging. Senescent cells exhibit characteristics such as the secretion of matrix-degrading enzymes and pro-inflammatory cytokines, collectively known as senescence-associated secretory phenotypes (SASPs). Many of these SASP cytokines and enzymes are implicated in the pathogenesis of tendinopathy. MicroRNA-146a (miR-146a) blocks senescence by targeting interleukin-1β (IL-1β) receptor-associated kinase 4 (IRAK-4) and TNF receptor-associated factor 6 (TRAF6), thus inhibiting NF-κB activity. The aims of this study were to (1) investigate miR-146a expression in tendinopathic tendons and (2) evaluate the role of miR-146a in countering senescence and SASPs in tendinopathic tenocytes.

METHODS

MiR-146a expression was assessed in human long head biceps (LHB) and rat tendinopathic tendons by in situ hybridization. MiR-146a over-expression in rat primary tendinopathic tenocytes was achieved by lentiviral vector-mediated precursor miR-146a transfer (LVmiR-146a). Expression of various senescence-related markers was analyzed by quantitative reverse transcription polymerase chain reaction (qRT-PCR), immunoblotting and immunofluorescence. MiR-146a expression showed a negative correlation with the severity of tendinopathy in human and rat tendinopathic tendons (p<0.001).

RESULTS

Tendinopathic tenocyte transfectants overexpressing miR-146a exhibited downregulation of various senescence and SASP markers, as well as the target molecules IRAK-4 and TRAF6, and the inflammatory mediator phospho-NF-κB. Additionally, these cells showed enhanced nuclear staining of high mobility group box 1 (HMGB1) compared to LVmiR-scramble-transduced controls in response to IL-1β stimulation.

CONCLUSIONS

We demonstrate that miR-146a expression is negatively correlated with the progression of tendinopathy. Moreover, its overexpression protects tendinopathic tenocytes from SASPs and senescence through the IRAK-4/TRAF6/NF-kB pathway.

Exercise mimetics: a novel strategy to combat neuroinflammation and Alzheimer's disease

Neuroinflammation is a pathological hallmark of Alzheimer's disease (AD), characterized by the stimulation of resident immune cells of the brain and the penetration of peripheral immune cells. These inflammatory processes facilitate the deposition of amyloid-beta (Aβ) plaques and the abnormal hyperphosphorylation of tau protein. Managing neuroinflammation to restore immune homeostasis and decrease neuronal damage is a therapeutic approach for AD. One way to achieve this is through exercise, which can improve brain function and protect against neuroinflammation, oxidative stress, and synaptic dysfunction in AD models. The neuroprotective impact of exercise is regulated by various molecular factors that can be activated in the same way as exercise by the administration of their mimetics. Recent evidence has proven some exercise mimetics effective in alleviating neuroinflammation and AD, and, additionally, they are a helpful alternative option for patients who are unable to perform regular physical exercise to manage neurodegenerative disorders. This review focuses on the current state of knowledge on exercise mimetics, including their efficacy, regulatory mechanisms, progress, challenges, limitations, and future guidance for their application in AD therapy.

Alzheimer's disease-induced phagocytic microglia express a specific profile of coding and non-coding RNAs

INTRODUCTION

Alzheimer's disease (AD) is a neurodegenerative disease and the main cause of dementia in the elderly. AD pathology is characterized by accumulation of microglia around the beta-amyloid (Aβ) plaques which assumes disease-specific transcriptional signatures, as for the disease-associated microglia (DAM). However, the regulators of microglial phagocytosis are still unknown.

METHODS

We isolated Aβ-laden microglia from the brain of 5xFAD mice for RNA sequencing to characterize the transcriptional signature in phagocytic microglia and to identify the key non-coding RNAs capable of regulating microglial phagocytosis. Through spatial sequencing, we show the transcriptional changes of microglia in the AD mouse brain in relation to Aβ proximity.

RESULTS

Finally, we show that phagocytic messenger RNAs are regulated by miR-7a-5p, miR-29a-3p and miR-146a-5p microRNAs and segregate the DAM population into phagocytic and non-phagocytic states.

DISCUSSION

Our study pinpoints key regulators of microglial Aβ clearing capacity suggesting new targets for future therapeutic approaches.

Regulation of miRNA-155-5p ameliorates NETosis in pulmonary fibrosis rat model via inhibiting its target cytokines IL-1β, TNF-α and TGF-β1

Idiopathic pulmonary fibrosis (IPF) is an age-related inflammatory disease with no cure up till now.It is accompanied by neutrophils infiltration as the main responders to inflammation and fibrosis. Importantly, neutrophils release neutrophil extracellular traps (NETs) through NETosis process. The function of microRNAs during inflammation became of great biological attention. Owing to microRNAs' central role in immune system, microRNA-155-5p (miR-155-5p) is intensely involved in the inflammatory response. Capsaicin (Cap) is a bioactive compound that exhibits antioxidative and anti-inflammatory functions. Recent studies have shown its role in regulation of certain microRNAs' expressions. Accordingly, the present study aims to investigate the effect of miR-155-5p regulation in suppressing NETs production via ameliorating its target inflammatory cytokines, IL-1ß, TNF-α and TGF-ß1, in bleomycin (BLM)-induced pulmonary fibrosis rat model treated by Cap. The obtained results demonstrated that miR-155-5p downregulation was associated with significant decrease in IL-1ß, TNF-α, TGF-β1, which consequently, reduced hydroxyproline (HYP), NETs activity markers as NE and PAD-4, and alleviated CTGF levels in lung tissues of animals treated by Cap. Furthermore, NETosis ultrastructure examination by transmission electron microscope (TEM), MPO immunohistochemical staining and histopathological studies confirmed an abolishment in NETs formation and an improvement in lung tissue architecture in Cap-treated rats. This study concluded that Cap quenched the inflammatory response through interrupting IL-1β, TNF-α and TGF-β1 pathway via modulating miR-155-5p expression. In addition, Cap was able to alleviate pulmonary NETosis markers by restraining NETs activity markers. These findings provide novel insight into the application of Cap-based treatment in ameliorating pulmonary damage in IPF.

Exploring the role of IL-1β in inflammatory bowel disease pathogenesis

Interleukin 1β (IL-1β) is a significant mediator of inflammation and tissue damage in IBD. The balance between IL-1β and its endogenous inhibitor-IL-1Ra-, plays a critical role in both initiation and regulation of inflammation. However, the precise role of IL-1β as a causative factor in IBD or simply a consequence of inflammation remains unclear. This review summarizes current knowledge on the molecular and cellular characteristics of IL-1β, describes the existing evidence on the role of this cytokine as a modulator of intestinal homeostasis and an activator of inflammatory responses, and also discusses the role of microRNAs in the regulation of IL-1β-related inflammatory responses in IBD. Current evidence indicates that IL-1β is involved in several aspects during IBD as it greatly contributes to the induction of pro-inflammatory responses through the recruitment and activation of immune cells to the gut mucosa. In parallel, IL-1β is involved in the intestinal barrier disruption and modulates the differentiation and function of T helper (Th) cells by activating the Th17 cell differentiation, known to be involved in the pathogenesis of IBD. Dysbiosis in the gut can also stimulate immune cells to release IL-1β, which, in turn, promotes inflammation. Lastly, increasing evidence pinpoints the central role of miRNAs involvement in IL-1β-related signaling during IBD, particularly in the maintenance of homeostasis within the intestinal epithelium. In conclusion, given the crucial role of IL-1β in the promotion of inflammation and immune responses in IBD, the targeting of this cytokine or its receptors represents a promising therapeutic approach. Further research into the IL-1β-associated post-transcriptional modifications may elucidate the intricate role of this cytokine in immunomodulation.

Exploring the Therapeutic Significance of microRNAs and lncRNAs in Kidney Diseases

MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are two crucial classes of transcripts that belong to the major group of non-coding RNAs (ncRNAs). These RNA molecules have significant influence over diverse molecular processes due to their crucial role as regulators of gene expression. However, the dysregulated expression of these ncRNAs constitutes a fundamental factor in the etiology and progression of a wide variety of multifaceted human diseases, including kidney diseases. In this context, over the past years, compelling evidence has shown that miRNAs and lncRNAs could be prospective targets for the development of next-generation drugs against kidney diseases as they participate in a number of disease-associated processes, such as podocyte and nephron death, renal fibrosis, inflammation, transition from acute kidney injury to chronic kidney disease, renal vascular changes, sepsis, pyroptosis, and apoptosis. Hence, in this current review, we critically analyze the recent findings concerning the therapeutic inferences of miRNAs and lncRNAs in the pathophysiological context of kidney diseases. Additionally, with the aim of driving advances in the formulation of ncRNA-based drugs tailored for the management of kidney diseases, we discuss some of the key challenges and future prospects that should be addressed in forthcoming investigations.

Identification and Characterization of Immune-Associated MicroRNAs in Silver Carp (Hypophthalmichthys molitrix) Responding to Aeromonas veronii and LPS Stimulation

The ubiquitous Gram-negative bacterial pathogen Aeromonas veronii (A. veronii) can easily cause inflammatory reactions in aquatic organisms, resulting in high mortality and huge economic losses. MicroRNAs (miRNAs) participate in immune regulation and have certain conserved properties. MiRNAs are involved in the immune responses of a variety of teleost fish infected with bacteria, whereas there is no related report in silver carp (Hypophthalmichthys molitrix). Therefore, we identified the expression profiles of miRNA in silver carp stimulated by A. veronii and LPS. Among them, the quantity of differentially expressed miRNAs (DEmiRNAs) obtained in the silver carp challenge group was 73 (A. veronii) and 90 (LPS). The GO enrichment and analysis of KEGG pathways have shown that the predicted target genes are mainly associated with lipid metabolism and the immune response in silver carp. This indicates the possibility that miRNAs play a role in regulating immune-related pathways. In addition, a total of eight DEmiRNAs validated the accuracy of the sequencing result via quantitative real-time PCR (qRT-PCR). Finally, we selected the silver carp head kidney macrophage cells (HKCs) as model cells and proved that miR-30b-5p can regulate the inflammatory response in silver carp HKCs. This study lays the foundation for exploring miRNA regulation in silver carp during pathogenic bacterial infection. In addition, it provides a reference for the future development of non-coding RNA antibacterial drugs.

Integrative role of small non-coding RNAs in viral immune response: a systematic review

Various viruses cause viral infection, and these viruses have different microscopic sizes, genetic material, and morphological forms. Due to a viral infection, the host body induces defense mechanisms that activate the innate and adaptive immune system. sncRNAs are involved in various biological processes and play an essential role in antiviral response in viruses including ZIKV, HCV, DENV, SARS-CoV, and West Nile virus, and regulate the complex interactions between the viruses and host cells. This review discusses the role of miRNAs, siRNAs, piRNAs, and tiRNAs in antiviral response. Cellular miRNAs bind with virus mRNA and perform their antiviral response in multiple viruses. However, the chemical modifications of miRNA necessary to avoid nuclease attack, which is then involved with intracellular processing, have proven challenging for therapeutic replacement of miRNAs. siRNAs have significant antiviral responses by targeting any gene of interest along the correct nucleotide of targeting mRNA. Due to this ability, siRNAs have valuable characteristics in antiviral response for therapeutic purposes. Additionally, the researchers noted the involvement of piRNAs and tiRNAs in the antiviral response, yet their findings were deemed insignificant.

Extracellular vesicles of iPS cells highly capable of producing HGF and TGF-β1 can attenuate Sjögren's syndrome via innate immunity regulation

Previous studies have demonstrated that extracellular vesicles (EVs) from dental pulp stem cells (DPSCs), which release abundant hepatocyte growth factor (HGF) and transforming growth factor-β1 (TGF-β1), contribute to the pathogenesis of Sjögren's syndrome (SS). However, depending on the condition of DPSCs, this effect is often not achieved. In this study, we established induced pluripotent stem (iPS) cells highly capable of releasing HGF and TGF-β1 and iPS cells barely capable of releasing them, and administered each EV to SS model mice to see if there was a difference in therapeutic effect. EVs were collected from each iPS cell and their characteristics and shapes were examined. When they were administered to SS model mice, the EVs from iPS cells with higher concentrations of HGF and TGF-β1 showed significantly reduced inflammatory cell infiltration in salivary gland tissues, increased saliva volume, and decreased anti-SS-A and anti-SS-B antibodies. A comprehensive search of microRNA arrays for differences among those EVs revealed that EVs from iPS cells with higher concentrations of HGF and TGF-β1 contained more of the let-7 family. Thereafter, we examined the expression of toll-like receptors (TLRs), which are said to be regulated by the let-7 family, by qPCR, and found decreased TLR4 expression. Focusing on MAPK, a downstream signaling pathway, we examined cytokine concentrations in mouse macrophage culture supernatants and Western blotting of murine splenic tissues and found higher concentrations of anti-inflammatory cytokines in the EVs-treated group and decreased TLR4, NF-κB and phosphorylation (p)-p-38 MAPK expression by Western blotting. Alternatively, p-Smad2/3 was upregulated in the EVs-treated group. Our findings suggest that the let-7 family in EVs may suppress the expression of TLR4 and NF-κB, which may be involved in the suppression of MAPK-mediated pro-inflammatory cytokine production.

STAT3 Deficiency Alters the Macrophage Activation Pattern and Enhances Matrix Metalloproteinase 9 Expression during Staphylococcal Pneumonia

Staphylococcus aureus is a significant cause of morbidity and mortality in pulmonary infections. Patients with autosomal-dominant hyper-IgE syndrome due to STAT3 deficiency are particularly susceptible to acquiring staphylococcal pneumonia associated with lung tissue destruction. Because macrophages are involved in both pathogen defense and inflammation, we investigated the impact of murine myeloid STAT3 deficiency on the macrophage phenotype in vitro and on pathogen clearance and inflammation during murine staphylococcal pneumonia. Murine bone marrow-derived macrophages (BMDM) from STAT3 LysMCre+ knockout or Cre- wild-type littermate controls were challenged with S. aureus, LPS, IL-4, or vehicle control in vitro. Pro- and anti-inflammatory responses as well as polarization and activation markers were analyzed. Mice were infected intratracheally with S. aureus, bronchoalveolar lavage and lungs were harvested, and immunohistofluorescence was performed on lung sections. S. aureus infection of STAT3-deficient BMDM led to an increased proinflammatory cytokine release and to enhanced upregulation of costimulatory MHC class II and CD86. Murine myeloid STAT3 deficiency did not affect pathogen clearance in vitro or in vivo. Matrix metalloproteinase 9 was upregulated in Staphylococcus-treated STAT3-deficient BMDM and in lung tissues of STAT3 knockout mice infected with S. aureus. Moreover, the expression of miR-155 was increased. The enhanced inflammatory responses and upregulation of matrix metalloproteinase 9 and miR-155 expression in murine STAT3-deficient as compared with wild-type macrophages during S. aureus infections may contribute to tissue damage as observed in STAT3-deficient patients during staphylococcal pneumonia.

TNFα-Induced Altered miRNA Expression Links to NF-κB Signaling Pathway in Endometriosis

Endometriosis is a common gynecological inflammatory disorder characterized by immune system dysregulation, which is involved in lesion initiation and progression. Studies have demonstrated that several cytokines are associated with the evolution of endometriosis, including tumor necrosis factor-α (TNFα). TNFα is a non-glycosylated cytokine protein with potent inflammatory, cytotoxic, and angiogenic potential. In the current study, we examined the ability of TNFα to induce dysregulation of microRNAs (miRNAs) linked to NFkB signaling pathways, thus contributing to the pathogenesis of endometriosis. Using RT-qPCR, the expression of several miRNAs was quantified in primary cells derived from eutopic endometrium of endometriosis subjects (EESC) and normal endometrial stromal cells (NESC), and also TNFα-treated NESCs. The phosphorylation of the pro-inflammatory molecule NF-κB and the candidates of the survival pathways PI3K, AKT, and ERK was measured by western blot analysis. The elevated secretion of TNFα in EESCs downregulates the expression level of several miRNAs significantly in EESCs compared to NESCs. Also, treatment of NESCs with exogenous TNFα significantly reduced the expression of miRNAs in a dose-dependent manner to levels similar to EESCs. In addition, TNFα significantly increased the phosphorylation of the PI3K, AKT, ERK, and NF-κB signaling pathways. Notably, treatment with curcumin (CUR, diferuloylmethane), an anti-inflammatory polyphenol, significantly increased the expression of dysregulated miRNAs in EESC in a dose-dependent manner. Our findings demonstrate that TNFα is upregulated in EESCs, which subsequently dysregulates the expression of miRNAs, contributing to the pathophysiology of endometriotic cells. CUR effectively inhibits the expression of TNFα, subsequently altering miRNA levels and suppressing the phosphorylation of AKT, ERK, and NF-κB.

Differential gene expression of cytokines, receptors, and miRNAs in individuals living with HIV-1 and vaccinated against yellow fever

Between 2016 and 2018, Brazil faced a yellow fever (YF) outbreak, which led to an expansion of vaccination coverage. The coexistence of the YF outbreak and the HIV-1 epidemic in Brazil raised concerns regarding the immune response and vaccine effectiveness in individuals living with HIV (PLWH). The aim of this study was to investigate the immune response to YF vaccination in PLWH and HIV-uninfected individuals as controls. Transcript levels of immunomodulatory molecules, including IL-6, IL-10, IL-21, TGF-β, CD19, CD163, miR-21, miR-146, and miR-155, were measured using RTqPCR. TCD4+ cells were evaluated by cytometry, and neutralizing antibody (Nab) titers were detected by a micro plaque-reduction neutralization test. The findings of our study revealed several noteworthy observations. First, there was a notable reduction in the circulation of TCD4+ cells postvaccination. Among people living with HIV (PLWH), we observed an increase in the expression of IL-10 following vaccination, while IL-6 expression was diminished in PLWH with lower TCD4+ counts. Furthermore, we identified the downregulation of CD19 and TGF-β, along with the upregulation of IL-21 and CD163. Notably, we observed positive correlations between the levels of IL-10/IL-21, IL-10/CD163, and IL-6/CD19. Additionally, there was a positive correlation between miRNAs 146 and 155. It is important to emphasize that all participants exhibited robust neutralizing antibody responses after receiving 17DD YF vaccination. In this context, the gene expression data presented can be useful for biomarker studies of protective antibodies induced by YF vaccination. This study sheds light on immune mechanisms in individuals living with HIV and YF vaccination.

LC-MS-Based Direct Quantification of MicroRNAs in Rat Blood

MicroRNA (miRNA) has recently garnered significant research attention, owing to its potential as a diagnostic biomarker and therapeutic target. Liquid chromatography-mass spectrometry (LC-MS) offers accurate quantification, multiplexing capacity, and high compatibility with various matrices. These advantages establish it as a preferred technique for detecting miRNA in biological samples. In this study, we presented an LC-MS method for directly quantifying seven miRNAs (rno-miR-150, 146a, 21, 155, 223, 181a, and 125a) associated with immune and inflammatory responses in rat whole blood. To ensure miRNA stability in the samples and efficiently purify target analytes, we compared Trizol- and proteinase K-based extraction methods, and the Trizol extraction proved to be superior in terms of analytical sensitivity and convenience. Chromatographic separation was carried out using an oligonucleotide C18 column with a mobile phase composed of N-butyldimethylamine, 1,1,1,3,3,3-hexafluoro-2-propanol, and methanol. For MS detection, we performed high-resolution full scan analysis using an orbitrap mass analyzer with negative electrospray ionization. The established method was validated by assessing its selectivity, linearity, limit of quantification, accuracy, precision, recovery, matrix effect, carry-over, and stability. The proposed assay was then applied to simultaneously monitor target miRNAs in lipopolysaccharide-treated rats. Although potentially less sensitive than conventional methods, such as qPCR and microarray, this direct-detection-based LC-MS method can accurately and precisely quantify miRNA. Given these promising results, this method could be effectively deployed in various miRNA-related applications.

Potential impact of trained innate immunity on the pathophysiology of metabolic dysfunction-associated fatty liver disease

Metabolic dysfunction-associated fatty liver disease (MAFLD) occurs in a low-grade inflammatory milieu dependent on highly complex networks that span well-beyond the hepatic tissue injury. Dysfunctional systemic metabolism that characterizes the disease, is further induced in response to environmental cues that modify energy and metabolic cellular demands, thereby altering the availability of specific substrates that profoundly regulate, through epigenetic mechanisms, the phenotypic heterogeneity of immune cells and influence hematopoietic stem cell differentiation fate. This immuno-metabolic signaling drives the initiation of downstream effector pathways and results in the decompensation of hepatic homeostasis that precedes pro-fibrotic events. Recent evidence suggests that innate immune cells reside in different tissues in a memory effector state, a phenomenon termed trained immunity, that may be activated by subsequent exogenous (e.g., microbial, dietary) or endogenous (e.g., metabolic, apoptotic) stmuli. This process leads to long-term modifications in the epigenetic landscape that ultimately precondition the cells towards enhanced transcription of inflammatory mediators that accelerates MAFLD development and/or progression. In this mini review we aimed to present current evidence on the potential impact of trained immunity on the pathophysiology of MAFLD, shedding light on the complex immunobiology of the disease and providing novel potential therapeutic strategies to restrain the burden of the disease.

Analysis of liver miRNA in Hu sheep with different residual feed intake

Feed efficiency (FE), an important economic trait in sheep production, is indirectly assessed by residual feed intake (RFI). However, RFI in sheep is varied, and the molecular processes that regulate RFI are unclear. It is thus vital to investigate the molecular mechanism of RFI to developing a feed-efficient sheep. The miRNA-sequencing (RNA-Seq) was utilized to investigate miRNAs in liver tissue of 6 out of 137 sheep with extreme RFI phenotypic values. In these animals, as a typical metric of FE, RFI was used to distinguish differentially expressed miRNAs (DE_miRNAs) between animals with high (n = 3) and low (n = 3) phenotypic values. A total of 247 miRNAs were discovered in sheep, with four differentially expressed miRNAs (DE_miRNAs) detected. Among these DE_miRNAs, three were found to be upregulated and one was downregulated in animals with low residual feed intake (Low_RFI) compared to those with high residual feed intake (High_RFI). The target genes of DE_miRNAs were primarily associated with metabolic processes and biosynthetic process regulation. Furthermore, they were also considerably enriched in the FE related to glycolysis, protein synthesis and degradation, and amino acid biosynthesis pathways. Six genes were identified by co-expression analysis of DE_miRNAs target with DE_mRNAs. These results provide a theoretical basis for us to understand the sheep liver miRNAs in RFI molecular regulation.

MiRNA-related metastasis in oral cancer: moving and shaking

Across the world, oral cancer is a prevalent tumor. Over the years, both its mortality and incidence have grown. Oral cancer metastasis is a complex process involving cell invasion, migration, proliferation, and egress from cancer tissue either by lymphatic vessels or blood vessels. MicroRNAs (miRNAs) are essential short non-coding RNAs, which can act either as tumor suppressors or as oncogenes to control cancer development. Cancer metastasis is a multi-step process, in which miRNAs can inhibit or stimulate metastasis at all stages, including epithelial-mesenchymal transition, migration, invasion, and colonization, by targeting critical genes in these pathways. On the other hand, long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), two different types of non-coding RNAs, can regulate cancer metastasis by affecting gene expression through cross-talk with miRNAs. We reviewed the scientific literature (Google Scholar, Scopus, and PubMed) for the period 2000-2023 to find reports concerning miRNAs and lncRNA/circRNA-miRNA-mRNA networks, which control the spread of oral cancer cells by affecting invasion, migration, and metastasis. According to these reports, miRNAs are involved in the regulation of metastasis pathways either by directly or indirectly targeting genes associated with metastasis. Moreover, circRNAs and lncRNAs can induce or suppress oral cancer metastasis by acting as competing endogenous RNAs to inhibit the effect of miRNA suppression on specific mRNAs. Overall, non-coding RNAs (especially miRNAs) could help to create innovative therapeutic methods for the control of oral cancer metastases.

Association between Urinary AGEs and Circulating miRNAs in Children and Adolescents with Overweight and Obesity from the Italian I.Family Cohort: A Pilot Study

Modern dietary habits are linked to high exposure to Advanced Glycation End products (AGEs) mainly due to the dramatic increase in the consumption of highly processed foods in recent years. Body levels of these compounds vary with food intake and are almost interconnected with age and health status, formally embodying indicators of oxidative stress and inflammation in adults. However, the relationship between AGEs and health issues has not been definitively understood in children, and several pediatric investigations have produced conflicting evidence. Besides, despite extensive research, there are no universally accepted analytical techniques for measuring AGE levels in the human body, with several approaches available, each with its advantages and disadvantages. This pilot study aimed to investigate the association between urinary AGEs, measured using spectrofluorimetry-based assays, and circulating microRNAs (c-miRNAs) in a subsample (n = 22) of Italian children participating in the I.Family Study. Anthropometric measurements, biochemical markers, and miRNA profiles were assessed. The first indication of a relationship between urinary AGEs and c-miRNAs in the context of obesity was found. Specifically, four miRNAs, hsa-miR-10b-5p, hsa-miR-501-5p, hsa-miR-874-3p, and hsa-miR-2355-5p were significantly associated with levels of urinary AGEs. The association between AGEs, obesity, inflammation markers, and specific miRNAs highlights the complex interplay between these factors and their potential impact on cellular and tissue homeostasis. The discovery of altered c-miRNAs profiling has the potential to offer innovative methods for assessing early changes in the body's AGE pool and allow recognition of an increased risk of disease susceptibility, routinely undetected until metabolic complications are identified.

Role of miR-24-3p and miR-146a-5p in dendritic cells' maturation process induced by contact sensitizers

MiRNAs are non-coding RNA molecules that regulate gene expression at the post-transcriptional level. Although allergic contact dermatitis has been studied extensively, few studies addressed miRNA expression and their role in dendritic cell activation. The main aim of this work was to investigate the role of miRNAs in the underlying mechanism of dendritic cell maturation induced by contact sensitizers of different potency. Experiments were conducted using THP-1-derived immature DCs (iDCs). Contact allergens of different potency were used: p-benzoquinone, Bandrowski's base, and 2,4-dinitrochlorobenzene as extreme; nickel sulfate hexahydrate, diethyl maleate and 2-mercaptobenzothiazole as moderate; and α-hexyl cinnamaldehyde, eugenol, and imidazolidinyl urea as weak. Selective inhibitor and mimic miRNAs were then used and several cell surface markers was evaluated as targets. Also, patients patch tested with nickel were analyzed to determine miRNAs expression. Results indicate an important role of miR-24-3p and miR-146a-5p in DCs activation. miR-24-3p was up-regulated by extreme and weak contact allergens, while miR-146a-5p was up-regulated by weak and moderate contact allergens and down-regulated only by the extreme ones. Also, the involvement of PKCβ in contact allergen-induced miR-24-3p and miR-146a-5p expression was demonstrated. Furthermore, the expression of the two miRNAs maintains the same trend of expression in both in vitro and in human conditions after nickel exposure. Results obtained suggest the involvement of miR-24 and miR-146a in DCs maturation process in the proposed in vitro model, supported also by human evidences.

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.

Digital PCR (dPCR) Quantification of miR-155-5p as a Potential Candidate for a Tissue Biomarker of Inflammation in Rabbits Infected with Lagovirus europaeus/Rabbit Hemorrhagic Disease Virus (RHDV)

MicroRNAs (miRNAs, miRs) are a group of small, 17-25 nucleotide, non-coding RNA sequences that, in their mature form, regulate gene expression at the post-transcriptional level. They participate in many physiological and pathological processes in both humans and animals. One such process is viral infection, in which miR-155 participates in innate and adaptive immune responses to a broad range of inflammatory mediators. Recently, the study of microRNA has become an interesting field of research as a potential candidate for biomarkers for various processes and disease. To use miRNAs as potential biomarkers of inflammation in viral diseases of animals and humans, it is necessary to improve their detection and quantification. In a previous study, using reverse transcription real-time quantitative PCR (RT-qPCR), we showed that the expression of ocu-miR-155-5p in liver tissue was significantly higher in rabbits infected with Lagovirus europaeus/Rabbit Hemorrhagic Disease Virus (RHDV) compared to healthy rabbits. The results indicated a role for ocu-miR-155-5p in Lagovirus europaeus/RHDV infection and reflected hepatitis and the impairment/dysfunction of this organ during RHD. MiR-155-5p was, therefore, hypothesized as a potential candidate for a tissue biomarker of inflammation and examined in tissues in Lagovirus europaeus/RHDV infection by dPCR. The objective of the study is the absolute quantification of ocu-miR-155-5p in four tissues (liver, lung, kidney, and spleen) of rabbits infected with Lagovirus europaeus/RHDV by digital PCR, a robust technique for the precise and direct quantification of small amounts of nucleic acids, including miRNAs, without standard curves and external references. The average copy number/µL (copies/µL) of ocu-miRNA-155-5p in rabbits infected with Lagovirus europaeus GI.1a/Rossi in the liver tissue was 12.26 ± 0.14, that in the lung tissue was 48.90 ± 9.23, that in the kidney tissue was 16.92 ± 2.89, and that in the spleen was 25.10 ± 0.90. In contrast, in the tissues of healthy control rabbits, the average number of copies/µL of ocu-miRNA-155-5p was 5.07 ± 1.10 for the liver, 23.52 ± 2.77 for lungs, 8.10 ± 0.86 for kidneys, and 42.12 ± 3.68 for the spleen. The increased expression of ocu-miRNA-155-5p in infected rabbits was demonstrated in the liver (a fold-change of 2.4, p-value = 0.0003), lung (a fold-change of 2.1, p-value = 0.03), and kidneys (a fold-change of 2.1, p-value = 0.01), with a decrease in the spleen (a fold-change of 0.6, p-value = 0.002). In the study of Lagovirus europaeus/RHDV infection and in the context of viral infections, this is the first report that shows the potential use of dPCR for the sensitive and absolute quantification of microRNA-155-5p in tissues during viral infection. We think miR-155-5p may be a potential candidate for a tissue biomarker of inflammation with Lagovirus europaeus/RHDV infection. Our report presents a new path in discovering potential candidates for the tissue biomarkers of inflammation.

Expression Profile of miR-199a and Its Role in the Regulation of Intestinal Inflammation

Early weaning stress impairs intestinal health in piglets. miRNAs are crucial for maintaining host homeostasis, while their implication for animal health remains unclear. To identify weaning-associated miRNAs, piglets were sampled at day 0, 1, 3, 7 and 14 after weaning. The data indicated that the highest levels of miR-199a-5p in jejunal villus upper cells were observed on day 14 after weaning, while the lowest levels in crypt cells were noted on day 7 and 14. In contrast, miR-199a-3p was down-regulated in both of these two cells on day 7 after weaning compared with day 0. Both miR-199a-5p and -3p were differently expressed along the villus-crypt axis. To further clarify the function of miR-199a, mice deficient in miR-199a were exposed to dextran sulfate sodium (DSS) to induce colitis. Results revealed that silencing of miR-199a enhanced sensitivity to DSS-induced colitis. Moreover, the increased morbidity and mortality were correlated with enhanced inflammatory cell infiltration, elevated pro-inflammatory cytokine expression, impaired barrier function, and a concomitant increase in permeability-related parameters. Bioinformatic analysis further demonstrated that lipid metabolism-related pathways were significantly enriched and Ndrg1 was verified as a target of miR-199a-3p. These findings indicate that miR-199a may be important for animal health management.

Inflammatory microRNAs in cardiovascular pathology: another brick in the wall

The regulatory role of microRNAs (miRNAs) is mainly mediated by their effect on protein expression and is recognized in a multitude of pathophysiological processes. In recent decades, accumulating evidence has interest in these factors as modulatory elements of cardiovascular pathophysiology. Furthermore, additional biological processes have been identified as new components of cardiovascular disease etiology. In particular, inflammation is now considered an important cardiovascular risk factor. Thus, in the present review, we will focus on the role of a subset of miRNAs called inflamma-miRs that may regulate inflammatory status in the development of cardiovascular pathology. According to published data, the most representative candidates that play functional roles in thromboinflammation are miR-21, miR-33, miR-34a, miR-146a, miR-155, and miR-223. We will describe the functions of these miRNAs in several cardiovascular pathologies in depth, with specific emphasis on the molecular mechanisms related to atherogenesis. We will also discuss the latest findings on the role of miRNAs as regulators of neutrophil extracellular traps and their impact on cardiovascular diseases. Overall, the data suggest that the use of miRNAs as therapeutic tools or biomarkers may improve the diagnosis or prognosis of adverse cardiovascular events in inflammatory diseases. Thus, targeting or increasing the levels of adequate inflamma-miRs at different stages of disease could help mitigate or avoid the development of cardiovascular morbidities.

TNFα-induced altered miRNA expression links to NF-κB signaling pathway in endometriosis

Endometriosis is a common gynecological inflammatory disorder characterized by immune system dysregulation, which is involved in lesion initiation and progression. Studies have demonstrated that several cytokines are associated with the evolution of endometriosis, including tumor necrosis factor-α (TNFα). TNFα is a non-glycosylated cytokine protein with potent inflammatory, cytotoxic, and angiogenic potential. In the current study, we examined the ability of TNFα to induce dysregulation of microRNAs (miRNAs) linked to NFkB-signaling pathways, thus contributing to the pathogenesis of endometriosis. Using RT-QPCR, the expression of several miRNAs were quantified in primary cells derived from eutopic endometrium of endometriosis subjects (EESC) and normal endometrial stromal cells (NESC) and also TNFα treated NESCs. The phosphorylation of the pro-inflammatory molecule NF-κB and the candidates of the survival pathways PI3K, AKT and ERK was measured by westernblot analysis. The elevated secretion of TNFα in EESCs downregulates the expression level of several miRNAs significantly (p < 0.05) in EESCs compared to NESC. Also treatment of NESCs with exogenous TNFα significantly reduced the expression of miRNAs in a dose-dependent manner to levels similar to EESCs. In addition, TNFα significantly increased the phosphorylation of the PI3K, AKT, ERK, and NF-κB signaling pathways. Notably, treatment with curcumin (CUR, diferuloylmethane), an anti-inflammatory polyphenol, significantly increased the expression of dysregulated miRNAs in EESC in a dose-dependent manner. Our findings demonstrate that TNFα is upregulated in EESCs, which subsequently dysregulates the expression of miRNAs, contributing to the pathophysiology of endometriotic cells. CUR effectively inhibits the expression of TNFα, subsequently altering miRNA levels and suppresses the phosphorylation of AKT, ERK, and NF-κB.

Sex-biased expression of selected chromosome x-linked microRNAs with potent regulatory effect on the inflammatory response in children with cystic fibrosis: A preliminary pilot investigation

Previous studies have reported sex disparity in cystic fibrosis (CF) disease, with females experiencing more pulmonary exacerbations and frequent microbial infections resulting in shorter survival expectancy. This concerns both pubertal and prepubertal females, which is in support to the prominent role of gene dosage rather than the hormonal status. The underlying mechanisms are still poorly understood. The X chromosome codes for a large number of micro-RNAs (miRNAs) that play a crucial role in the post-transcriptional regulation of several genes involved in various biological processes, including inflammation. However, their level of expression in CF males and females has not been sufficiently explored. In this study, we compared in male and female CF patients the expression of selected X-linked miRNAs involved in inflammatory processes. Cytokine and chemokine profiles were also evaluated at both protein and transcript levels and cross-analyzed with the miRNA expression levels. We observed increased expression of miR-223-3p, miR-106a-5p, miR-221-3p and miR-502-5p in CF patients compared to healthy controls. Interestingly, the overexpression of miR-221-3p was found to be significantly higher in CF girls than in CF boys and this correlates positively with IL-1β. Moreover, we found a trend toward lower expression in CF girls than in CF boys of suppressor of cytokine signaling 1 (SOCS1) and the ubiquitin-editing enzyme PDLIM2, two mRNA targets of miR-221-3p that are known to inhibit the NF-κB pathway. Collectively, this clinical study highlights a sex-bias in X-linked miR-221-3p expression in blood cells and its potential contribution to sustaining a higher inflammatory response in CF girls.

Investigation of the Expression Pattern and Functional Role of miR-10b in Intestinal Inflammation

Implications of miRNAs for animal health management in livestock remain elusive. To identify suitable miRNAs as monitoring biomarkers, piglets were randomly selected for sampling on days 0, 1, 3, 7, and 14 post-weaning. The results show that miR-10b levels in the villus upper cells of the jejunum on days 3 and 7 were significantly lower than that on day 14 post-weaning and reduced by approximately 30% on day 3 and 55% on day 7 compared to day 0. In contrast, miR-10b in crypt cells decreased by approximately 82% on day 7 and 64% on day 14 compared with day 0. Next, miR-10 knockout mice and wild-type mice were subjected to dextran sulfate sodium (DSS) for 7 days. The findings demonstrate that mice lacking miR-10b were more susceptible to DSS administration, as demonstrated by worse survival, greater weight loss, more severe tissue damage, and increased intestinal permeability. Moreover, the increased disease severity was correlated with enhanced macrophage infiltration, coincident with significantly elevated pro-inflammatory mediators and immunoglobulins. Bioinformatic analysis further reveals that the enriched pathways were mainly involved in host immune responses, and Igtp was identified as a potential target of miR-10b. These findings may provide new strategies for future interventions for swine health and production.

Association between inflammation, reward processing, and ibuprofen-induced increases of miR-23b in astrocyte-enriched extracellular vesicles: A randomized, placebo-controlled, double-blind, exploratory trial in healthy individuals

Ibuprofen, a non-steroidal, anti-inflammatory drug, modulates inflammation but may also have neuroprotective effects on brain health that are poorly understood. Astrocyte-enriched extracellular vesicles (AEEVs) facilitate cell-to-cell communication and - among other functions - regulate inflammation and metabolism via microribonucleic acids (miRNAs). Dysfunctions in reward-related processing and inflammation have been proposed to be critical pathophysiological pathways in individuals with mood disorders. This investigation examined whether changes in AEEV cargo induced by an anti-inflammatory agent results in inflammatory modulation that is associated with reward-related processing. Data from a double-blind, randomized, repeated-measures study in healthy volunteers were used to examine the effects of AEEV miRNAs on brain activation during reward-related processing. In three separate visits, healthy participants (N = 20) received a single dose of either placebo, 200 mg, or 600 mg of ibuprofen, completed the monetary incentive delay task during functional magnetic resonance imaging, and provided a blood sample for cytokine and AEEV collection. AEEV miRNA content profiling showed that ibuprofen dose-dependently increased AEEV miR-23b-3p expression with greater increase following the 600 mg administration than placebo. Those individuals who received 600 mg and showed the highest miR-23b-3p expression also showed the (a) lowest serum tumor necrosis factor (TNF) and interleukin-17A (IL-17A) concentrations; and had the (b) highest striatal brain activation during reward anticipation. These results support the hypothesis that ibuprofen alters the composition of miRNAs in AEEVs. This opens the possibility that AEEV cargo could be used to modulate brain processes that are important for mental health.

miRNAs: The Road from Bench to Bedside

miRNAs are small noncoding RNAs that control gene expression at the posttranscriptional level. It has been recognised that miRNA dysregulation reflects the state and function of cells and tissues, contributing to their dysfunction. The identification of hundreds of extracellular miRNAs in biological fluids has underscored their potential in the field of biomarker research. In addition, the therapeutic potential of miRNAs is receiving increasing attention in numerous conditions. On the other hand, many operative problems including stability, delivery systems, and bioavailability, still need to be solved. In this dynamic field, biopharmaceutical companies are increasingly engaged, and ongoing clinical trials point to anti-miR and miR-mimic molecules as an innovative class of molecules for upcoming therapeutic applications. This article aims to provide a comprehensive overview of current knowledge on several pending issues and new opportunities offered by miRNAs in the treatment of diseases and as early diagnostic tools in next-generation medicine.

(-)‑Epigallocatechin‑3‑O‑gallate upregulates the expression levels of miR‑6757‑3p, a suppressor of fibrosis‑related gene expression, in extracellular vesicles derived from human umbilical vein endothelial cells

As pulmonary fibrosis (PF), a severe interstitial pulmonary disease, has such a poor prognosis, the development of prevention and treatment methods is imperative. (-)-Epigallocatechin-3-O-gallate (EGCG), one of the major catechins in green tea, exerts an antifibrotic effect, although its mechanism remains unclear. Recently, it has been reported that microRNAs (miRNAs or miRs) transported by extracellular vesicles (EVs) from vascular endothelial cells (VECs) are involved in PF. In the present study, the effects of EGCG on the expression of miRNAs in EVs derived from human umbilical vein endothelial cells (HUVECs) were assessed and miRNAs with antifibrotic activity were identified. miRNA microarray analysis revealed that EGCG modulated the expression levels of 31 miRNAs (a total of 27 miRNAs were upregulated, and 4 miRNAs were downregulated.) in EVs from HUVECs. Furthermore, TargetScan analysis indicated that miR-6757-3p in particular, which exhibited the highest degree of change, may target transforming growth factor-β (TGF-β) receptor 1 (TGFBR1). To evaluate the effects of miR-6757-3p on TGFBR1 expression, human fetal lung fibroblasts (HFL-1) were transfected with an miR-6757-3p mimic. The results demonstrated that the miR-6757-3p mimic downregulated the expression of TGFBR1 as well the expression levels of fibrosis-related genes including fibronectin and α-smooth muscle actin in TGF-β-treated HFL-1 cells. In summary, EGCG upregulated the expression levels of miR-6757-3p, which may target TGFBR1 and downregulate fibrosis-related genes, in EVs derived from VECs.

Cervical microRNA expression and spontaneous preterm birth

BACKGROUND

Preterm birth remains a major public health issue affecting 10% of all pregnancies and increases risks of neonatal morbidity and mortality. Approximately 50% to 60% of preterm births are spontaneous, resulting from preterm premature rupture of membranes or preterm labor. The pathogenesis of spontaneous preterm birth is incompletely understood, and prediction of preterm birth remains elusive. Accurate prediction of preterm birth would reduce infant morbidity and mortality through targeted patient referral to hospitals equipped to care for preterm infants. Two previous studies have analyzed cervical microRNAs in association with spontaneous preterm birth and the length of gestation, but the extent to which microRNAs serve as predictive biomarkers remains unknown.

OBJECTIVE

This study aimed to examine associations between cervical microRNA expression and spontaneous preterm birth, with the specific goal of identifying a subset of microRNAs that predict spontaneous preterm birth.

STUDY DESIGN

We performed a prospective, nested, case-control study of 25 cases with spontaneous preterm birth and 49 term controls. Controls were matched to cases in a 2:1 ratio on the basis of age, parity, and self-identified race. Cervical swabs were collected at a mean gestational age of 17.1 (4.8) weeks of gestation, and microRNAs were analyzed using a quantitative polymerase chain reaction array. Normalized microRNA expression was compared between cases and controls, and a false discovery rate of 0.2 was applied to account for multiple comparisons. Histopathologic analysis of slides of cervical swab samples was performed to quantify leukocyte burden for adjustment in conditional regression models. We explored the use of Relief-based unsupervised identification of top microRNAs and support vector machines to predict spontaneous preterm birth. We performed microRNA enrichment analysis to explore potential biologic targets and pathways in which up-regulated microRNAs might be involved.

RESULTS

Of the 754 microRNAs on the polymerase chain reaction array, 346 were detected in ≥75% of participants' cervical swabs. Average cervical microRNA expression was significantly higher in cases of spontaneous preterm birth than in controls (P=.01). There were 95 significantly up-regulated individual microRNAs (>2-fold change) in cases of subsequent spontaneous preterm birth compared with term controls (P<.05; q<0.2). Notably, miR-143, miR-30e-3p, and miR-199b were all significantly up-regulated, which is consistent with the 1 previous study of cervical microRNA and spontaneous preterm birth. A Relief-based, novel variable (feature) selection machine learning approach had low-to-moderate prediction accuracy, with an area under the receiver operating curve of 0.71. Enrichment analysis revealed that identified microRNAs may modulate inflammatory cell signaling.

CONCLUSION

In this prospective nested case-control study of cervical microRNA expression and spontaneous preterm birth, we identified a global increase in microRNA expression and up-regulation of 95 distinct microRNAs in association with subsequent spontaneous preterm birth. Larger and more diverse studies are required to determine the ability of microRNAs to accurately predict spontaneous preterm birth, and mechanistic work to facilitate development of novel therapeutic interventions to prevent spontaneous preterm birth is warranted.

Molecular profile of the NF-κB signalling pathway in human colorectal cancer

The development and progression of colorectal cancer (CRC) have been associated with inflammation processes that involve the overactivation of the NF-κB signalling pathway. The characterization of the NF-κB expression profile in CRC is an important topic since the suppression of NF-κB represents a potential therapeutic approach. In this study, we assessed the expression levels of 84 NF-κB-related genes in paired tumoral (T) and peritumoral (PT) tissues from 18 CRC patients and 18 normal colonic mucosae, and the expression levels of three miRNAs targeting the most dysregulated genes revealed by the case-control analysis. Comparing the gene expression profile of T and controls, 60 genes were dysregulated. The comparison of T and PT revealed 17 dysregulated genes in the tumoral tissues, with IL1B, CXCL8, IL1A, and CSF2 being the most upregulated. Notably, through a bioinformatics analysis, the differential gene expression of 11 out of the 17 genes was validated on a larger cohort of 308 CRC patients compared with 41 controls. Moreover, a decrease in the levels of RELA, NOD1, CASP8, BCL2L1, ELK1, and IKBKB was identified in poorly differentiated tumours compared to moderately differentiated tumours. The analysis of the three miRNAs targeting IL1B, CXCL8, IL1A, and CSF2 showed that miR-182-5p was upregulated in T compared with PT, whereas miR-10b-5p was downregulated in T compared with PT and control tissues. Our results may contribute to the design of new experimental therapeutic strategies based on endogenous molecules, such as miRNAs, to target the genetic key players of the NF- κB pathway.

Targeting epigenetic regulators for inflammation: Mechanisms and intervention therapy

Emerging evidence indicates that resolution of inflammation is a critical and dynamic endogenous process for host tissues defending against external invasive pathogens or internal tissue injury. It has long been known that autoimmune diseases and chronic inflammatory disorders are characterized by dysregulated immune responses, leading to excessive and uncontrol tissue inflammation. The dysregulation of epigenetic alterations including DNA methylation, posttranslational modifications to histone proteins, and noncoding RNA expression has been implicated in a host of inflammatory disorders and the immune system. The inflammatory response is considered as a critical trigger of epigenetic alterations that in turn intercede inflammatory actions. Thus, understanding the molecular mechanism that dictates the outcome of targeting epigenetic regulators for inflammatory disease is required for inflammation resolution. In this article, we elucidate the critical role of the nuclear factor-κB signaling pathway, JAK/STAT signaling pathway, and the NLRP3 inflammasome in chronic inflammatory diseases. And we formulate the relationship between inflammation, coronavirus disease 2019, and human cancers. Additionally, we review the mechanism of epigenetic modifications involved in inflammation and innate immune cells. All that matters is that we propose and discuss the rejuvenation potential of interventions that target epigenetic regulators and regulatory mechanisms for chronic inflammation-associated diseases to improve therapeutic outcomes.

Serum miR-34a as a potential biomarker for diagnosis of inflammatory bowel diseases in Egyptian patients

Background

IBD is a multifactorial disease. Although dysbiosis of commensal bacteria and breakdown of the intestinal barrier are considered as major pathological mechanisms in the development of IBD, other important factors such as genetic aberrations also contribute to its development.

Results

Our results revealed that serum miR-34a RQ values were significantly lower and serum MACF1 RQ values were significantly higher in IBD patients compared to healthy controls. In addition, serum miR-34a in relation to pathological activity and disease severity in the IBD group revealed a significant difference (p>0.05).

Conclusion

Serum miR-34a RQ and serum MACF1 RQ value-based biomarker panels can act as a potential biomarker for IBD diagnosis and prognosis.

Adipose and Plasma microRNAs miR-221 and 222 Associate with Obesity, Insulin Resistance, and New Onset Diabetes after Peritoneal Dialysis

BACKGROUND

The correlation between microRNA, obesity, and glycemic intolerance in patients on peritoneal dialysis (PD) is unknown. We aimed to measure the adipose and plasma miR-221 and -222 levels, and to evaluate their association with adiposity, glucose intolerance, and new onset diabetes mellitus (NODM) after the commencement of PD.

METHODS

We prospectively recruited incident adult PD patients. miR-221 and -222 were measured from adipose tissue and plasma obtained during PD catheter insertion. These patients were followed for 24 months, and the outcomes were changes in adiposity, insulin resistance, and NODM after PD.

RESULTS

One hundred and sixty-five patients were recruited. Patients with pre-existing DM had higher adipose miR-221 (1.1 ± 1.2 vs. 0.7 ± 0.9-fold, p = 0.02) and -222 (1.9 ± 2.0 vs. 1.2 ± 1.3-fold, p = 0.01). High adipose miR-221 and -222 levels were associated with a greater increase in waist circumference (miR-221: beta 1.82, 95% CI 0.57-3.07, p = 0.005; miR-222: beta 1.35, 95% CI 0.08-2.63, p = 0.038), Homeostatic Model Assessment for Insulin Resistance (HOMA) index (miR-221: beta 8.16, 95% CI 2.80-13.53, p = 0.003; miR-222: beta 6.59, 95% CI 1.13-12.05, p = 0.018), and insulin requirements (miR-221: beta 0.05, 95% CI 0.006-0.09, p = 0.02; miR-222: beta 0.06, 95% CI 0.02-0.11, p = 0.002) after PD. The plasma miR-222 level predicted the onset of NODM (OR 8.25, 95% CI 1.35-50.5, p = 0.02).

CONCLUSION

miR-221 and -222 are associated with the progression of obesity, insulin resistance, and NODM after PD.

Peripheral inflammatory markers during an acute bacterial infection in older patients with and without cognitive dysfunction: A case control study

Dementia is a known risk factor for acute bacterial infections which may also play a significant role in promoting or accelerating cognitive impairment. Pneumonia and urinary tract infections are the main cause of hospitalisation of dementia patients and infections are a major precipitant of delirium. It is well established that peripheral immune signals induce a neuroinflammatory response largely mediated by microglial cells which is amplified with advanced age, neurodegenerative disorders and genetic characteristics. Reversely, the innate immune response to acute bacterial infection is tightly regulated by the brain. It remains unclear whether dysfunctional neural circuits affected by dementia and/or delirium could alter systemic innate immune responses at the periphery. The current study aims to determine if dementia and/or delirium are associated with an altered systemic inflammatory response to an acute bacterial infection. We recruited 46 hospitalised older patients with acute bacterial infections. From these, 29 participants had cognitive dysfunction (6 with delirium, 12 with dementia and 11 with delirium superimposed on dementia) and 17 had normal cognition. We also included a control group of 11 patients with dementia but with no current infection matched for age and educational status. Baseline characteristics were tested between groups using Kruskal-Wallis test and pairwise comparisons were subsequently assessed with Bonferroni correction for multiple comparisons for continuous variables. Chi square test was used to assess differences between groups in categorical data and correlations between peripheral inflammatory parameters were assessed with Spearman's test. The 4 groups with infection and the control group with no infection had similar characteristics except for cognitive function and functionality which was higher for the group of infected cognitively healthy participants. Levels of C-reactive protein were similar between the infected groups and higher than the non-infected dementia group. Infected patients with cognitive dysfunction (delirium and/or dementia) had higher serum levels of IL-6, TNF-alpha and IL-1beta. These participants had reduced expression of miR-145 in circulating exosomes which correlated negatively with miR-155 levels (r = −0.411, p = 0.027). Expression of CR1 in circulating CD14⁺ monocytes was higher in infected participants with cognitive dysfunction and, in this group, PICALM correlated both with TNF-alpha and IL-6. In contrast to what was observed in participants with normal cognition, expression of CR1 did not correlate with DAP12 in infected participants with cognitive dysfunction. Taken together, our findings suggest that cognitive dysfunction is associated with an exaggerated proinflammatory response during acute bacterial infection with deregulation of several molecular signalling pathways in circulating exosomes and in monocytes.

Upregulation of microRNA-125b-5p alleviates acute liver failure by regulating the Keap1/Nrf2/HO-1 pathway

Background

Acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) are the two most common subtypes of liver failure. They are both life-threatening clinical problems with high short-term mortality. Although liver transplantation is an effective therapeutic, its application is limited due to the shortage of donor organs. Given that both ACLF and ALF are driven by excessive inflammation in the initial stage, molecules targeting inflammation may benefit the two conditions. MicroRNAs (miRNAs) are a group of small endogenous noncoding interfering RNA molecules. Regulation of miRNAs related to inflammation may serve as promising interventions for the treatment of liver failure.

Aims

To explore the role and mechanism of miR-125b-5p in the development of liver failure.

Methods

Six human liver tissues were categorized into HBV-non-ACLF and HBV-ACLF groups. Differentially expressed miRNAs (DE-miRNAs) were screened and identified through high-throughput sequencing analysis. Among these DE-miRNAs, miR-125b-5p was selected for further study of its role and mechanism in lipopolysaccharide (LPS)/D-galactosamine (D-GalN) -challenged Huh7 cells and mice in vitro and in vivo.

Results

A total of 75 DE-miRNAs were obtained. Of these DE-miRNAs, miR-125b-5p was the focus of further investigation based on our previous findings and preliminary results. We preliminarily observed that the levels of miR-125b-5p were lower in the HBV-ACLF group than in the HBV-non-ACLF group. Meanwhile, LPS/D-GalN-challenged mice and Huh7 cells both showed decreased miR-125b-5p levels when compared to their untreated control group, suggesting that miR-125b-5p may have a protective role against liver injury, regardless of ACLF or ALF. Subsequent results revealed that miR-125b-5p not only inhibited Huh7 cell apoptosis in vitro but also relieved mouse ALF in vivo with evidence of improved liver histology, decreased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and reduced tumor necrosis factor-α (TNF-α) and IL-1β levels. Based on the results of a biological prediction website, microRNA.org, Kelch-like ECH-associated protein 1 (Keap1) was predicted to be one of the target genes of miR-125b-5p, which was verified by a dual-luciferase reporter gene assay. Western blot results in vitro and in vivo showed that miR-125b-5p could decrease the expression of Keap1 and cleaved caspase-3 while upregulating the expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and heme oxygenase-1(HO-1).

Conclusion

Upregulation of miR-125b-5p can alleviate acute liver failure by regulating the Keap1/Nrf2/HO-1 pathway, and regulation of miR-125b-5p may serve as an alternative intervention for liver failure.

Selenium-Stimulated Exosomes Enhance Wound Healing by Modulating Inflammation and Angiogenesis

Mesenchymal stem cell (MSC)-derived exosomes have emerged as an attractive cell-free tool in tissue engineering and regenerative medicine. The current study aimed to examine the anti-inflammatory, pro-angiogenic, and wound-repair effects of both exosomes and selenium-stimulated exosomes, and check whether the latter had superior wound healing capacity over others. The cellular and molecular network of exosomes, as a paracrine signal, was extensively studied by performing miRNA arrays to explore the key mediators of exosomes in wound healing. Selenium is known to play a critical role in enhancing the proliferation, multi-potency, and anti-inflammatory effects of MSCs. Selenium-stimulated exosomes showed significant effects in inhibiting inflammation and improving pro-angiogenesis in human umbilical vein endothelial cells. Cell growth and the migration of human dermal fibroblasts and wound regeneration were more enhanced in the selenium-stimulated exosome group than in the selenium and exosome groups, thereby further promoting the wound healing in vivo. Taken together, selenium was found to augment the therapeutic effects of adipose MSC-derived exosomes in tissue regeneration. We concluded that selenium may be considered a vital agent for wound healing in stem cell-based cell-free therapies.