Dysregulated MicroRNA Involvement in Multiple Sclerosis by Induction of T Helper 17 Cell Differentiation

The relationship of peripheral blood lncRNA-PVT1 and miR-146a levels with Th17/Treg cytokines in patients with Hashimoto's thyroiditis and their clinical significance

Hashimoto's thyroiditis (HT) is a prevalent autoimmune disease. We investigated the relationship of peripheral blood long noncoding RNA-plasmacytoma variant translocation 1 (lncRNA-PVT1) and microRNA (miR)-146a levels with Th17/Treg-related cytokines in HT patients and their clinical significance. Correlations of PVT1 and miR-146a with Th17/Treg-related cytokines were analyzed, and its clinical value in diagnosing HT was assessed. Results showed reduced lncRNA-PVT1 and interleukin (IL)-10 levels and increased miR-146a and IL-17 levels in HT patients. lncRNA-PVT1 negatively interrelated with miR-146a, IL-17, IL-23 and IL-6, and positively interrelated with IL-10; miR-146a positively correlated with IL-17, IL-23 and IL-6, but negatively correlated with IL-10 in HT patients. The area under the curve (AUC) of lncRNA-PVT1 and miR-146a levels for diagnosing HT were 0.822 and 0.844, respectively (sensitivity 88.73% and 86.62%, specificity 67.02% and 69.15%, cut-off values 0.76 and 2.73), with their combined detections yielding a higher AUC. Patients with poorly expressed lncRNA-PVT1 and highly expressed miR-146a had elevated HT incidence. lncRNA-PVT1 and miR-146a levels were also found to be an independent influencing factor for HT occurrence. Our findings suggest that HT patients have low peripheral blood lncRNA-PVT1 expression and high miR-146a expression. lncRNA-PVT1 and miR-146a level changes were correlated with Th17/Treg cytokine imbalance and could be a potential diagnostic tool and independent influencing factor for HT.

Low-intensity pulsed ultrasound protects from inflammatory dilated cardiomyopathy through inciting extracellular vesicles

AIMS

CD4+ T cells are activated during inflammatory dilated cardiomyopathy (iDCM) development to induce immunogenic responses that damage the myocardium. Low-intensity pulsed ultrasound (LIPUS), a novel physiotherapy for cardiovascular diseases, has recently been shown to modulate inflammatory responses. However, its efficacy in iDCM remains unknown. Here, we investigated whether LIPUS could improve the severity of iDCM by orchestrating immune responses and explored its therapeutic mechanisms.

METHODS AND RESULTS

In iDCM mice, LIPUS treatment reduced cardiac remodelling and dysfunction. Additionally, CD4+ T-cell inflammatory responses were suppressed. LIPUS increased Treg cells while decreasing Th17 cells. LIPUS mechanically stimulates endothelial cells, resulting in increased secretion of extracellular vesicles (EVs), which are taken up by CD4+ T cells and alter their differentiation and metabolic patterns. Moreover, EVs selectively loaded with microRNA (miR)-99a are responsible for the therapeutic effects of LIPUS. The hnRNPA2B1 translocation from the nucleus to the cytoplasm and binding to caveolin-1 and miR-99a confirmed the upstream mechanism of miR-99a transport. This complex is loaded into EVs and taken up by CD4+ T cells, which further suppress mTOR and TRIB2 expression to modulate cellular differentiation.

CONCLUSION

Our findings revealed that LIPUS uses an EVs-dependent molecular mechanism to protect against iDCM progression. Therefore, LIPUS is a promising new treatment option for iDCM.

Immunoregulatory Effects of the Active Form of Vitamin D (Calcitriol), Individually and in Combination with Curcumin, on Peripheral Blood Mononuclear Cells (PBMCs) of Multiple Sclerosis (MS) Patients

OBJECTIVES

Multiple sclerosis (MS) is a chronic autoimmune inflammatory disease affecting the central nervous system. Immune cell subsets, notably T helper (Th) 17 and Th1, exert important roles in MS pathogenesis. Whereas, Treg cells modulate the disease process. Calcitriol, the active form of vitamin D, and curcumin, a bioactive compound derived from turmeric, play immunomodulatory effects relevant to autoimmune disorders, including MS. The objective of this study is to investigate the effects of calcitriol and Curcumin on Peripheral blood mononuclear cells (PBMCs) of individuals with MS.

METHODS

PBMCs from twenty MS patients were isolated, cultured, and exposed to 0.004 μg/mL of calcitriol and 10 μg/mL of curcumin. The cells underwent treatment with singular or combined doses of these components to assess potential cumulative or synergistic immunomodulatory effects. Following treatment, the expression levels of genes and the cellular population of Treg, Th1 and Th17 were evaluated using Real-time PCR and flow cytometry.

RESULTS

Treatment with curcumin and calcitriol led to a significant reduction in the expression levels of inflammatory cytokines and transcription factors related to Th1 and Th17 cells, including IFN-γ, T-bet, IL-17, and RORC. Furthermore, the frequency of these cells decreased following treatment. Additionally, curcumin and calcitriol treatment resulted in a significant upregulation of the FOXP3 gene expression and an increase in the frequency of Treg cells.

CONCLUSION

This study demonstrates that curcumin and calcitriol can effectively modulate the inflammatory processes intrinsic to MS by mitigating the expression of inflammatory cytokines by Th1 and Th17 cells while concurrently enhancing the regulatory role of Treg cells. Moreover, the combined treatment of curcumin and calcitriol did not yield superior outcomes compared to single-dosing strategies.

MicroRNAs in infectious diseases: potential diagnostic biomarkers and therapeutic targets

MicroRNAs (miRNAs) are conserved, short, non-coding RNAs that play a crucial role in the post-transcriptional regulation of gene expression. They have been implicated in the pathogenesis of cancer and neurological, cardiovascular, and autoimmune diseases. Several recent studies have suggested that miRNAs are key players in regulating the differentiation, maturation, and activation of immune cells, thereby influencing the host immune response to infection. The resultant upregulation or downregulation of miRNAs from infection influences the protein expression of genes responsible for the immune response and can determine the risk of disease progression. Recently, miRNAs have been explored as diagnostic biomarkers and therapeutic targets in various infectious diseases. This review summarizes our current understanding of the role of miRNAs during viral, fungal, bacterial, and parasitic infections from a clinical perspective, including critical functional mechanisms and implications for their potential use as biomarkers and therapeutic targets.

The role of microRNAs involved in the disorder of blood-brain barrier in the pathogenesis of multiple sclerosis

miRNAs are involved in various vital processes, including cell growth, development, apoptosis, cellular differentiation, and pathological cellular activities. Circulating miRNAs can be detected in various body fluids including serum, plasma, saliva, and urine. It is worth mentioning that miRNAs remain stable in the circulation in biological fluids and are released from membrane-bound vesicles called exosomes, which protect them from RNase activity. It has been shown that miRNAs regulate blood-brain barrier integrity by targeting both tight junction and adherens junction molecules and can also influence the expression of inflammatory cytokines. Some recent studies have examined the impact of certain commonly used drugs in Multiple Sclerosis on miRNA levels. In this review, we will focus on the recent findings on the role of miRNAs in multiple sclerosis, including their role in the cause of MS and molecular mechanisms of the disease, utilizing miRNAs as diagnostic and clinical biomarkers, using miRNAs as a therapeutic modality or target for Multiple Sclerosis and drug responses in patients, elucidating their importance as prognosticators of disease progression, and highlighting their potential as a future treatment for MS.

Bone marrow mesenchymal stem cells to ameliorate experimental autoimmune encephalomyelitis via modifying expression patterns of miRNAs

INTRODUCTION

Clinical and experimental studies highlighted the significant therapeutic role of Mesenchymal stem cells (MSCs) in neurodegenerative diseases. MSCs possess potent immunomodulatory properties by releasing exosomes, which generate a suitable microenvironment. microRNAs (miRNAs), as one of several effective bioactive molecules of exosomes, influence cellular communication and activities in recipient cells. Recent studies revealed that miRNAs could control the progression of multiple sclerosis (MS) via differentiation and function of T helper cells (Th).

METHODS

Here, we investigated the therapeutic effects of syngeneic-derived BM-MSC in experimental autoimmune encephalomyelitis (EAE) mouse model of MS by evaluating expression profile of miRNAs, pro- and anti-inflammatory in serum and brain tissues. Three-time scheme groups (6th day, 6th & 12th days, and 12th day, of post-EAE induction) were applied to determine the therapeutic effects of intraperitoneally received 1*106 of BM-MSCs.

RESULTS

The expression levels of mature isoforms of miR-193, miR-146a, miR-155, miR-21, and miR-326 showed that BM-MSCs treatment attenuated the EAE clinical score and reduced clinical inflammation as well as demyelination. The improved neurological functional outcome associated with enhanced expression of miR-193 and miR-146a, but decreased expression levels of miR-155, miR-21, and miR-326 were followed by suppressing effects on Th1/Th17 immune responses (reduced levels of IFN-γand IL-17 cytokine expression) and induction of Treg cells, immunoregulatory responses (increase of IL-10, TGF-β, and IL-4) in treatment groups.

CONCLUSION

Our findings suggest that BM-MSCs administration might change expression patterns of miRNAs and downstream interactions followed by immune system modulation. However, there is a need to carry out future human clinical trials and complementary experiments.

The role of miRNAs in multiple sclerosis pathogenesis, diagnosis, and therapeutic resistance

In recent years, microRNAs (miRNAs) have gained increased attention from researchers around the globe. Although it is twenty nucleotides long, it can modulate several gene targets simultaneously. Their mal expression is a signature of various pathologies, and they provide the foundation to elucidate the molecular mechanisms of each pathology. Among the debilitating central nervous system (CNS) disorders with a growing prevalence globally is the multiple sclerosis (MS). Moreover, the diagnosis of MS is challenging due to the lack of disease-specific biomarkers, and the diagnosis mainly depends on ruling out other disabilities. MS could adversely affect patients' lives through its progression, and only symptomatic treatments are available as therapeutic options, but an exact cure is yet unavailable. Consequently, this review hopes to further the study of the biological features of miRNAs in MS and explore their potential as a therapeutic target.

Vitamins A and D Enhance the Expression of Ror-γ-Targeting miRNAs in a Mouse Model of Multiple Sclerosis

Autoreactive T cells, particularly those characterized by a Th17 phenotype, exert significant influence on the pathogenesis of multiple sclerosis (MS). The present study aimed to elucidate the impact of individual and combined administration of vitamin A and D on neuroinflammation, and microRNAs (miRNAs) involved in T helper (Th)17 development, utilizing a murine model of experimental autoimmune encephalomyelitis (EAE). EAE was induced in C57BL/6 mice, and 3 days prior to immunization, intraperitoneal injections of vitamins A and D or their combination were administered. Th17 cell percentages were determined in splenocytes utilizing intracellular staining and flow cytometry. Furthermore, the expression of Ror γ-t, miR-98-5p and Let-7a-5p, was measured in both splenocytes and spinal cord tissues using RT-PCR. Treatment with vitamin A and D resulted in a reduction in both disease severity in EAE mice. Treated mice showed a decreased frequency of Th17 cells and lower expression levels of IL17 and Ror γ-t in splenocytes and spinal cord. The spinal cord tissues and splenocytes of mice treated with vitamins A, D, and combined A+D showed a significant upregulation of miR-98-5p and Let-7a-5p compared to the EAE group. Statistical analysis indicated a strong negative correlation between miR-98-5p and Let-7a-5p levels in splenocytes and Ror-t expression. Our findings indicate that the administration of vitamins A and D exerts a suppressive effect on neuroinflammation in EAE that is associated with a reduction in the differentiation of T cells into the Th17 phenotype and is mediated by the upregulation of miR-98-5p and Let-7a-5p, which target the Ror γ-t.

Association between the Cytosine Hydroxymethylation and the Expression of microRNA in Multiple Sclerosis in Polish Population

Multiple sclerosis is a chronic demyelinating disorder with an unclear etiology. A key role is thought to be played by Th17 cells and microRNAs associated with Th17, such as miR-155, miR-326 and miR-223. The present study compared the methylation and hydroxymethylation levels of CpG sites within promoters of these microRNA between MS patients and controls using PBMCs and analyzed their relationship with microRNA expression. Significant intergroup differences were found between the levels of 5-hmC within the CpG-1 miR-155 promoter and CpG within the miR-326 promoter; in addition, miR-155-5p and miR-223-3p expression was elevated in MS patients. Correlation analysis showed a positive relationship between the level of 5-hmC of CpG-2 in the miR-223 promoter and miR-223-3p level. As it is possible to pharmacologically modulate the level of epigenetic modifications, our findings cast light on the etiology of MS and support the development of more effective therapies.

RNA-binding proteins as a common ground for neurodegeneration and inflammation in amyotrophic lateral sclerosis and multiple sclerosis

The neurodegenerative and inflammatory illnesses of amyotrophic lateral sclerosis and multiple sclerosis were once thought to be completely distinct entities that did not share any remarkable features, but new research is beginning to reveal more information about their similarities and differences. Here, we review some of the pathophysiological features of both diseases and their experimental models: RNA-binding proteins, energy balance, protein transportation, and protein degradation at the molecular level. We make a thorough analysis on TDP-43 and hnRNP A1 dysfunction, as a possible common ground in both pathologies, establishing a potential link between neurodegeneration and pathological immunity. Furthermore, we highlight the putative variations that diverge from a common ground in an atemporal course that proposes three phases for all relevant molecular events.

Expression of Long Noncoding RNA, HOTAIR, and MicroRNA-205 and Their Relation to Transforming Growth Factor β1 in Patients with Alopecia Areata

Introduction

Alopecia areata (AA) is a common autoimmune condition that affects anagen hair follicles. The most commonly recognized theory is that it is a T-cell-mediated autoimmune disorder in a genetically susceptible individual. MicroRNAs (miRNAs) and long noncoding RNAs (lncRNAs) were thought to play a function in the pathogenesis. The expression of lncRNA HOTAIR and miRNA-205 and their relation to transforming growth factor β1 (TGF-β1) in AA were not studied.

Aim

The aim of the studywas to evaluate the role of miRNA-205, lncRNA, HOTAIR, and TGF-β1 levels in AA pathogenesis, clinical course, and severity of AA.

Methods

Two groups of subjects were included in this case-control study: 50 patients with AA and 50 healthy matched controls. miRNA-205 and lncRNA HOTAIR expression levels were assayed using quantitative RT-PCR, while serum levels of TGF-β1 were assayed using ELISA techniques.

Results

The serum expression of lncRNA HOTAIR was significantly downregulated in AA patients with a p value < 0.001, while the serum expression of both miRNA-205 and TGF-β1 were significantly upregulated in patients.

Discussion/Conclusion

This study highlights the potential role of high serum expression of miRNA-205 and TGF-β1 and the low serum expression of lncRNA HOTAIR in AA pathogenesis. This could be used as a therapeutic target to treat AA.

Investigation of Relationship Between Small Noncoding RNA (sncRNA) Expression Levels and Serum Iron, Copper, and Zinc Levels in Clinical Diagnosed Multiple Sclerosis Patients

In our study, we aimed to investigate the relationship between microRNA (miRNA) expression levels and serum iron (Fe), copper (Cu), and zinc (Zn) levels in Multiple sclerosis (MS) patients. Total RNA was isolated from peripheral venous blood containing ethylenediaminetetraacetic acid (EDTA) of MS patients and controls. Total RNA was labeled with Cy3-CTP fluorescent dye. Hybridization of samples was performed on microarray slides and arrays were scanned. Data argument and bioinformatics analysis were performed. Atomic absorption spectrophotometer method was used to measure serum Fe, Cu, and Zn levels. In our study, in bioinformatics analysis, although differently expressed miRNAs were not detected between 16 MS patients and 16 controls, hsa-miR-744-5p upregulation was detected between 4 MS patients and 4 controls. This may be stem from the patient group consisting of MS patients who have never had an attack for 1 year. Serum iron levels were detected significantly higher in the 16 MS patients compared to the 16 controls. This may be stem from the increase in iron accumulation based on inflammation in MS disease. According to the findings in our study, hsa-miR-744-5p upregulation has been determined as an early diagnostic biomarker for the development together of insulin resistance, diabetes mellitus associated with insulin signaling, and Alzheimer's diseases. Therefore, hsa-miR-744-5p is recommended as an important biomarker for the development together of diabetes mellitus, Alzheimer's disease, and MS disease. In addition, increased serum Fe levels may be suggested as an important biomarker for neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, and MS disease.

Relationship between the Occurrence of Genetic Variants of Single Nucleotide Polymorphism in microRNA Processing Genes and the Risk of Developing Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune demyelinating disorder of the central nervous system (CNS), which leads to disturbances in the conduction of nerve impulses, cognitive impairment, sensory and motor disturbances, as well as depressive symptoms. MS remains an incurable disease with a difficult diagnosis and unclear etiology. The aim of the analysis was to identify SNPs that may potentially be associated with an increased risk of developing MS. Blood samples were obtained from patients with MS (194 subjects) and age-matched healthy controls (188 subjects). The polymorphic variant frequencies of rs197412 T>C in GEMIN3, rs7813 G>A in GEMIN4, rs1106042 G>A in HIWI, rs10719 A>C in DROSHA, rs3742330 A>G in DICER1, rs11077 T>G in XPO5, rs14035 C>T in RAN, rs636832 G>A in AGO1 were determined in DNA using real-time PCR TaqMan® SNP Genotyping Assay. Our findings indicate that the GG AGO1 rs636832 and AA GEMIN4 rs7813 genotypes were associated with an increased risk of MS. Although our findings provide a clearer understanding of the pathogenesis of MS, further investigations are needed to better understand their potential for the evaluation of other miRNA processing genes believed to be associated with MS etiology.

Anti-Caspr-conjugated gold nanoparticles emergence as a novel approach in the treatment of EAE animal model

Multiple sclerosis (MS) is a chronic autoimmune disorder of central nervous system which is increasing worldwide. Although immunosuppressive agents are used for the treatment of MS disease, nevertheless the lack of non-toxic and efficient therapeutic method is perceptible. Hence, this study aims to evaluate the effect of Contactin-associated protein (Caspr) antibody-, poly ethylene glycol (PEG)- and exosome combined gold nanoparticles (GNPs) in comparison to Glatiramer acetate as a selective treatment of MS disease in the experimental autoimmune encephalomyelitis (EAE) mouse model. EAE was induced in female C57BL/6 mice and 25-day treatment with anti-Caspr-, PEG- and exosome combined GNPs was evaluated. Histopathological examination of spinal cord, regulatory T cells as well as inflammatory pathway including IFN-ɣ and IL-17 and mir-326 were investigated. The results showed the severity of MS symptoms was significantly decreased in all treated groups. Histological examination of the spinal cord indicated the reduced demyelination and immune cell infiltration. Besides, regulatory T cells were significantly increased following all treatments. Remarkably, the cytokine levels of IFN-ɣ and IL-17 as well as mir-326 is altered in treated groups. Taken together, the obtained findings demonstrate that the administration of anti-Caspr-, PEG- and exosome combined GNPs can be considered a potential treatment in MS disease.

Curcumin as an effective suppressor of miRNA expression in patients with knee osteoarthritis

Objective

Osteoarthritis is the most common disease in the group of joint diseases, and its incidence is directly related to aging. Given the anti-inflammatory effects of curcumin as an active ingredient of turmeric, we aimed to investigate the effects of this compound in a new curcumin nanomicelle formula named SinaCurcumin® on the expression of microRNAs (miRNAs) involved in immune responses of patients with osteoarthritis.

Materials and Methods

We divided 30 patients with osteoarthritis into two groups namely, nano curcumin-receiving (15 patients) and placebo-receiving (15 patients) and we studied them for 3 months. The Iranian Registry of Clinical Trials (IRCT) approved our study with the IRCT registry No. IRCT20151028024760N4. We evaluated the rates of the expression of microRNAs 146, 155, 16, and 138 employing SYBR Green Real-Time PCR method.

Results

The expression of miRNAs 155, 138, and 16 revealed a significant reduction in the curcumin-receiving group (p=0.002, p=0.024 and p=0.0001 respectively).

Conclusion

Our research data indicated that the consumption of curcumin in patients with osteoarthritis could affect the immune system partially via altering the expression of microRNAs and cytokines.

Upregulated miR-146a expression in peripheral blood relates to Th17 and Treg imbalance in elder rheumatoid arthritis patients

BACKGROUND

The expression level of microRNA-146a (miR-146a) increased in peripheral blood and synovialis tissue of rheumatoid arthritis (RA) patient, it may play an important role in the pathological process of RA. We investigated its possibility as a diagnostic marker and the correlation with Th17 and Treg cells in elder RA patients.

METHODS

Blood samples were collected from 38 active RA patients, 38 inactive RA patients, and 40 healthy controls. RNA expression levels of miR-146a were detected from the peripheral blood samples. The proportion of Th17 and Treg cells were analyzed, as well as their cell-specific transcription factor retinoic acid-related orphan receptor variant 2 (RORc) and forkhead box protein 3 (FOXP3). Furthermore, secretion of pre-inflammatory and anti-inflammatory factors were detected. Correlations between miR-146a and these factors were also analyzed.

RESULTS

Compared with healthy control, expression levels of miR-146a in inactive and active groups were significant higher, with the highest level in active group. The expression of miR-146a and the RA severity, T helper 17 (Th17) cell ratio, RORc expression, IL-17 level showed a significant positive correlation, while it showed a significantly negative correlation with Treg cell ration, FOXP3 expression, and TGF-β1 secretion.

CONCLUSIONS

These results suggested that miR-146a may be used as a disease progression marker in the peripheral blood of elder RA patients.

miR-150-5p and let-7b-5p in Blood Myeloid Extracellular Vesicles Track Cognitive Symptoms in Patients with Multiple Sclerosis

Cognitive deficits strongly affect the quality of life of patients with multiple sclerosis (MS). However, no cognitive MS biomarkers are currently available. Extracellular vesicles (EVs) contain markers of parental cells and are able to pass from the brain into blood, representing a source of disease biomarkers. The aim of this study was to investigate whether small non-coding microRNAs (miRNAs) targeting synaptic genes and packaged in plasma EVs may reflect cognitive deficits in MS patients. Total EVs were precipitated by Exoquick from the plasma of twenty-six cognitively preserved (CP) and twenty-three cognitively impaired (CI) MS patients belonging to two independent cohorts. Myeloid EVs were extracted by affinity capture from total EVs using Isolectin B4 (IB4). Fourteen miRNAs targeting synaptic genes were selected and measured by RT-PCR in both total and myeloid EVs. Myeloid EVs from CI patients expressed higher levels of miR-150-5p and lower levels of let-7b-5p compared to CP patients. Stratification for progressive MS (PMS) and relapsing-remitting MS (RRMS) and correlation with clinical parameters suggested that these alterations might be attributable to cognitive deficits rather than disease progression. This study identifies miR-150-5p and let-7b-5p packaged in blood myeloid EVs as possible biomarkers for cognitive deficits in MS.

Bioinformatic Analysis Reveals Hub Immune-Related Genes of Diabetic Foot Ulcers

Diabetic foot ulcer (DFU) is a complex and devastating complication of diabetes mellitus that are usually stagnant in the inflammatory phase. However, oral wound healing, which is characterized by a rapid and scarless healing process, is regarded an ideal model of wound healing. Thus, we performed a comprehensive bioinformatics analysis of the previously published data regarding oral ulcers and DFUs and found that compared to oral wound healing, the activated pathways of DFUs were enriched in cellular metabolism-related pathways but lacked the activation of inflammatory and immune-related pathways. We also found that CXCL11, DDX60, IFI44, and IFI44L were remarkable nodes since they had the most connections with other members of the module. Meanwhile, CXCL10, IRF7, and DDX58 together formed a closed-loop relationship and occupied central positions in the entire network. The real-time polymerase chain reaction and western blot was applied to validate the gene expression of the hub immune-related genes in the DFU tissues, it was found that CXCL11, IFI44, IFI44L, CXCL10 and IRF7 have a significant difference compared with normal wound tissues. Our research reveals some novel potential immune-related biomarkers and provides new insights into the molecular basis of this debilitating disease.

Evaluation of the expressed miR-129 and miR-549a in patients with multiple sclerosis

Background:

The expression of microRNAs (miRNAs) as circulating biomarkers has been underlined in multiple sclerosis (MS) in the last decade. Due to the presence of a possible relationship between expressed miRNAs and heterogeneous appearances of the pathological processes in MS, the present study attempts to evaluate the expression of miR-129 and miR-549a in patients with MS in comparison with healthy control (HC) group.

Materials and Methods:

Peripheral blood mononuclear cells were separated from fifty patients with MS (subtypes including relapsing–remitting MS and secondary progressive MS) in the Kashani Hospital, Isfahan, Iran, and fifty people as HC group. After RNA extraction and complementary DNA synthesis, the expression of miR-129 and miR-549a was evaluated in patients with MS in comparison with the HC group using a quantitative real-time polymerase chain reaction assay. The data were analyzed using the Kolmogorov–Smirnov and Mann–Whitney tests. Spearman's correlation coefficient was used to examine the relationship between miR-129 and miR-549a with age.

Results:

The results showed that the expression of miR-129 and miR-549a was not significant in patients with MS in comparison with the HC group. Furthermore, the relationship between such miRNAs and age and gender was not significant.

Conclusion:

We suggest the expression of miR-129 and miR-549a as circulating miRNAs in peripheral blood mononuclear cells could not be considered a biomarker for diagnosis and Para clinical.

Maggot treatment promotes healing of diabetic foot ulcer wounds possibly by upregulating Treg levels

PURPOSE

Through the study of regulatory T cells (Tregs), we found a possible way to promote the healing of diabetic foot ulcers (DFUs) with maggot treatment and investigated the associated mechanism.

METHODS

Immunohistochemistry was used to examinetissues from DFU patients treated with or without maggot debridement therapy (MDT). The expression of the signature Treg molecule Foxp3, interleukin-10 (IL-10), transforming growth factor-beta (TGF-β), and interferon regulatory factor 4 (IRF-4) in patients with DFU treated with or without MDT was tested by real-time PCR (RT-PCR). CD4⁺ T cells from mouse spleen cells were cocultured in vitro with maggot excretions/secretions (ES), and Foxp3, IL-10, TGF-β, and IRF-4 levels were measured by RT-PCR.

RESULTS

Foxp3 expression was obviously increased in DFU patients treated using MDT but less pronounced in those treated without MDT (P < 0.05). Foxp3, IL-10, TGF-β, and IRF-4 gene expression levels were higher in DFU patients treated with MDT than in those treated without MDT. Moreover, in vitro coculture of mouse spleen cells with ESs produced results consistent with the in vivo results (P < 0.001).

CONCLUSION

MDT/ESs can obviously upregulate the Treg level and may affect DFU healing in different ways, suggesting a new direction for the future treatment of DFU.

The Effect of Interferon-Beta Therapy on T-Helper 17/miR-326 and T-Helper 1/miR-29b-3p Axis in Relapsing-Remitting Multiple Sclerosis Patients

BACKGROUND

We aimed to evaluate the therapeutic effects of interferon-beta (IFN-β) on hsa-miR29b-3p and hsa-miR326 in isolated T-helper (Th)1 and Th17 cells expressed by relapsing-remitting multiple sclerosis (RRMS) patients before and after 1 year of treatment with IFN-β.

METHODS

The study was done on 19 RRMS patients pre- and posttreatment with IFN-β to evaluate the frequency of Th1 and Th17 cells by flow cytometry. The expression level of hsa-miR-29b-3p and hsa-miR-326 in isolated Th1 and Th17 cells was assessed by quantitative polymerase chain reaction. Enzyme-linked immunosorbent assay was also used to measure the plasma levels of I interferon -gamma and interleukin (IL)-17A.

RESULTS

Th17 cells and plasma levels of IL-17A decreased in RRMS patients after IFN-β therapy but hsa-miR-29b-3p and hsa-miR-326 expression had no significant change in treated RRMS patients versus baseline. MxA gene expression was significantly induced upon IFN-β therapy in patients with RRMS.

CONCLUSION

IFN-β therapy is more effective on Th17 than Th1, but it does not reform altered expression of hsa-miR-326 and hsa-miR-29b-3p in Th17 and Th1, respectively.

MicroRNA-7188-5p and miR-7235 regulates Multiple sclerosis in an experimental mouse model

The short non-coding microRNAs (miRNAs) have emerged as reliable modulators of various pathological conditions including autoimmune diseases in mammals. The current study, aims to identify new potential differential expressed miRNAs and their downstream mRNA targets of the autoimmune disease, Multiple sclerosis (MS). The study identifies a new set of miRNA(s) that are probably implicated in MS using computational tools. The study further carried-out different in vivo and in vitro experiments to check these identified miRNAs could be role in as therapeutic and prognostic applications. Preliminary insilico screening revealed that miR-659-3p, miR-659-5p, miR-684, miR-3607-3p, miR-3607-5p, miR-3682-3p, miR-3682-5p miR-4647, miR-7188-3p, miR-7188-5p and miR-7235 are specifically elevated in the secondary lymphoid cells of EAE mice. In addition, expression of the downstream target mRNA of these miRNAs such as FXBO33, SGMS-1, ZDHHC-9, GABRA-3, NRXN-2 were reciprocal to miRNA expression in lymphoid cells. These confirmed by applying the mimic and silencing miRNA models, suggesting new inflammatory target genes of these promising miRNA markers. The in vivo adoptive transfer model revealed that the suppression of miRNA-7188-5p and miR-7235 changed the pattern of astrocytes and CNS pathophysiology. The current study opens a new miRNA and their mRNA targets in MS disease. The absence of miRNA-7188-5p and miR-7235 enhanced the disease alleviation, confirms the regulatory effect of these targets. These optimized results highlights new set of miRNA's with therapeutic potential in experimental MS. Further studies are required to confirm these miRNA as therapeutic biomarker.

Overexpression of miR-1298 attenuates myocardial ischemia-reperfusion injury by targeting PP2A

Previous studies reported that microRNA-1298 was abnormally expressed in the myocardium of rat hearts after hypoxia/normoxia injury. This study aims to investigate the function and specific mechanism of miR-1298 in myocardial ischemia/reperfusion (IR) injury. Neonatal rat cardiomyocytes (NRCMs) were isolated from neonatal rat hearts and subjected to oxygen/glucose deprivation/reperfusion (OGD/R) to induce I/R injury. The rat model with I/R injury was induced by ligating the proximal left anterior descending artery (LAD). MiR-1298 expression was detected by qRT-PCR. The levels of PP2A, Bcl-2, Bax, and AMPK signaling members (p-AMPK, p-GSK3β) was detected by Western blot. Cell apoptosis was evaluated by TUNEL staining assay and flow cytometry. The infarct size of rat hearts was assessed by TTC staining assay. Premature and mature MiR-1298 were significantly downregulated while PP2A was significantly upregulated during I/R injury both in vitro and in vivo. The prediction of Starbase suggested that PP2A was a potential target of miR-1298. MiR-1298 overexpression significantly reduced cardiomyocyte apoptosis in vitro, and its protective effect was obviously attenuated by PP2A overexpression. Luciferase reporter assay showed that miR-1298 targeted PP2A directly. In addition, miR-1298 overexpression significantly reduced infarct size and cardiomyocyte apoptosis in the hearts of rats received with I/R injury in vivo. Moreover, miR-1298 overexpression significantly elevated the levels of Bcl-2 and AMPK signaling members (p-AMPK, p-GSK3β) while decreased Bax level, and these effects were partially reversed by PP2A overexpression. MiR-1298 participated in myocardial I/R injury by targeting the PP2A/AMPK/GSK3β signaling pathway, suggesting that miR-1298 might be a potential therapeutic target for myocardial I/R injury.

MicroRNAs, Multiple Sclerosis, and Depression

Multiple sclerosis (MS) is a chronic disease of the central nervous system that affects the brain and spinal cord. There are several disease courses in MS including relapsing–remitting MS (RRMS), primary progressive MS (PPMS), and secondary progressive MS (SPMS). Up to 50% of MS patients experience depressive disorders. Major depression (MD) is a serious comorbidity of MS. Many dysfunctions including neuroinflammation, peripheral inflammation, gut dysbiosis, chronic oxidative and nitrosative stress, and neuroendocrine and mitochondrial abnormalities may contribute to the comorbidity between MS and MD. In addition to these actions, medical treatment and microRNA (miRNA) regulation may also be involved in the mechanisms of the comorbidity between MS and MD. In the study, I review many common miRNA biomarkers for both diseases. These common miRNA biomarkers may help further explore the association between MS and MD.

Identifying miRNAs in multiple sclerosis gray matter lesions that correlate with atrophy measures

OBJECTIVE

Multiple sclerosis (MS) is an inflammatory, demyelinating and neurodegenerative disease of the central nervous system (CNS). Though MS was initially considered to be a white matter demyelinating disease, myelin loss in cortical gray matter has been reported in all disease stages. We previously identified microRNAs (miRNAs) in white matter lesions (WMLs) that are detected in serum from MS patients. However, miRNA expression profiles in gray matter lesions (GMLs) from progressive MS brains are understudied.

METHODS

We used a combination of global miRNAs and gene expression profiling of GMLs and independent validation using real-time quantitative polymerase chain reaction (RT-qPCR), immuno-in situ hybridization, and immunohistochemistry.

RESULTS

Compared to matched myelinated gray matter (GM) regions, we identified 82 miRNAs in GMLs, of which 10 were significantly upregulated and 17 were significantly downregulated. Among these 82 miRNAs, 13 were also detected in serum and importantly were associated with brain atrophy in MS patients. The predicted target mRNAs of these miRNAs belonged to pathways associated with axonal guidance, TGF-β signaling, and FOXO signaling. Further, using state-of-the-art human protein-protein interactome network analysis, we mapped the four key GM atrophy-associated miRNAs (hsa-miR-149*, hsa-miR-20a, hsa-miR-29c, and hsa-miR-25) to their target mRNAs that were also changed in GMLs.

INTERPRETATION

Our study identifies miRNAs altered in GMLs in progressive MS brains that correlate with atrophy measures. As these miRNAs were also detected in sera of MS patients, these could act as markers of GML demyelination in MS.

The Role of Extracellular Vesicles in Demyelination of the Central Nervous System

It is being increasingly demonstrated that extracellular vesicles (EVs) are deeply involved in the physiology of the central nervous system (CNS). Processes such as synaptic activity, neuron-glia communication, myelination and immune response are modulated by EVs. Likewise, these vesicles may participate in many pathological processes, both as triggers of disease or, on the contrary, as mechanisms of repair. EVs play relevant roles in neurodegenerative disorders such as Alzheimer’s or Parkinson’s diseases, in viral infections of the CNS and in demyelinating pathologies such as multiple sclerosis (MS). This review describes the involvement of these membrane vesicles in major demyelinating diseases, including MS, neuromyelitis optica, progressive multifocal leukoencephalopathy and demyelination associated to herpesviruses.

Apamin administration impact on miR-219 and miR-155-3p expression in cuprizone induced multiple sclerosis model

Multiple sclerosis (MS) is a chronic debilitating disease that attacks the central nervous system. This study aims to investigate miR-219 and miR-155-3p expression levels involved in the myelination process following the administration of apamin peptide in the model of multiple sclerosis disease. Forty-four 8 week C57BL/6 male mice (22 ± 5 g) randomly divided into six groups. Apamin (100 µg/kg/BW) was administered intraperitoneally as a co-treatment during phase I (demyelination) or post-treatment phase II (remyelination) twice a week in cuprizone induced MS model. At the end of study myelin content and microRNA expression levels were measured with LFB staining and quantitative Real-Time PCR method, respectively. It was observed that the intended microRNAs were dysregulated during the different phases of disease induction. After 6 weeks of cuprizone exposure, miR-219 downregulated in phase I in comparison with the negative control. On the other hand, the apamin co-treatment significantly inhibit the miR-155-3p upregulation during the phase I as compared with the cuprizone group (p < 0.0001). Apamin has more impact on the miR155-3p reduction in phase I than miR-219 elevation in phase II. It could be considered as a therapeutic option for decreasing plaque formation during the exacerbation phase of the MS disease. Apamin has more impact on the miR155-3p reduction in phase I than miR-219 elevation in phase II. It could be considered as a therapeutic option for decreasing plaque formation during the exacerbation phase of the MS disease.

Upregulation of miR-9 and miR-193b over human Th17 cell differentiation

BACKGROUND

Th17 cells are a newly discovered subset of CD4⁺ T cells known as key participants in various immune responses and inflammatory conditions including autoimmune diseases. Mi(cro)RNAs are a family of non-coding RNAs that regulate numerous critical immune functions. Immuno-miRNAs modulate cell biological processes in T cells, such as differentiation and function of Th17 cells. The aim of the present study is to investigate the expression of miR-9-5p, miR-193b-3p, and autoimmunity-related genes during human Th17 cells differentiation.

METHODS

Human naïve CD4⁺ T cells were purified from peripheral blood mononuclear cells (PBMCs) by magnetic cell sorting system (MACS) and their purity was checked by flow-cytometric analysis. Naïve CD4⁺ T cells were cultured under Th17-polarizing condition for 6 days. IL- 17 secretion was determined by means of enzyme-linked immunosorbent assay (ELISA). Next, the expression levels of miRNAs and putative targets genes were assessed by qRT-PCR at different time points of differentiation.

RESULTS

Our result showed dramatic downregulation of TCF7, MAP3K1, ENTPD1, and NT5E genes during human Th17 differentiation. Polarization also had a significant inducible effect on the expression of miR-9 and miR-193b over differentiation of human Th17 cells. According to our results, miR-9-5p and miR-193b-3p may contribute to Th17 differentiation probably by inhibiting the expression of negative regulators of Th17 differentiation.

CONCLUSION

This study confirmed deregulation of TCF7, MAP3K1, ENTPD1, and NT5E genes in Th17 differentiation process and introduced miR-9 and miR-193b as Th17 cell-associated miRNAs, making them good candidates for further investigations.

miRNA profile is altered in a modified EAE mouse model of multiple sclerosis featuring cortical lesions

Cortical lesions represent a hallmark of multiple sclerosis and are proposed as a predictor of disease severity. microRNAs are suggested to be important players in the disease pathogenesis and the experimental autoimmune encephalomyelitis animal model. We implemented a mouse model recapitulating more closely the human pathology as it is characterized by both an autoimmune heterogeneity and the presence of cortical lesions, two parameters missing in experimental autoimmune encephalomyelitis. In our model, mice clustered in two groups displaying high or low clinical scores. Upon cortical cytokine injection, lesions appeared with a specific topography while cortical miRNA profiles were altered. These two features differed according to disease severity. We evidenced changes in miRNA regulators and targets suggesting that miRNA alteration had functional repercussions that could explain the differences in cortical lesions. This model represents a crucial tool for the study of both miRNA involvement and cortical lesion formation in disease pathogenesis.

Organic Field-Effect Transistor Platform for Label-Free, Single-Molecule Detection of Genomic Biomarkers

The increasing interest in technologies capable of tracking a biomarker down to the physical limit points toward new opportunities in early diagnostics of progressive diseases. Indeed, single-molecule detection technologies are foreseen to enable clinicians to associate the tiniest increase in a biomarker with the progression of a disease, particularly at its early stage. Bioelectronic organic transistors represent an extremely powerful tool to achieve label-free and single-molecule detection of clinically relevant biomarkers. These electronic devices are millimetric in size and in the future could be mass-produced at low cost. The core of the single molecule with a large transistor (SiMoT) platform, based on an electrolyte-gated field-effect transistor, is a gold gate electrode biofunctionalized with a self-assembled monolayer, a densely packed layer of recognition elements. So far, only the SiMoT detection of proteins, using the corresponding antibodies as recognition elements, has been reported. In this study, the SiMoT sensing response toward genomic biomarkers is proposed. Herein, the gate is functionalized with a genomic biomarker for multiple sclerosis (miR-182). This is relevant, not only because a limit of detection of a single molecule is achieved but also because it proves that the SiMoT label-free, single-molecule detection principle is the only one of its kind that can detect, by means of the same platform, both protein and genomic markers.

Regulatory function of microRNAs in microglia

Microglia are CNS-resident cells involved in immune surveillance and maintenance of intercellular homeostasis, while also contributing to neurologic pathologies. MicroRNAs (miRNAs) are a class of small (~22 nucleotides) single-stranded noncoding RNAs that participate in gene regulation at the post-transcriptional level. miRNAs typically bind to the untranslated region (3' UTR) of RNAs. It has been shown that miRNAs are important players in controlling inflammation and that their abnormal expression is linked to cancer and ageing, and to the onset and progression of neurodegenerative disease. Furthermore, miRNAs participate in intercellular trafficking. Thus, miRNAs are released from cells in a free form, bound to proteins or packaged within extracellular vesicles (EVs), exerting paracrine and long distance signaling. In this review, recent findings on the role of miRNAs as drivers of microglia phenotypic changes and their cotribution in neurological disease are addressed. MAIN POINTS: miRNAs have a key role in microglia function/dysfunction, polarization, and restoration. Microglia are both a source and recipient of extracellular vesicles (EVs) containing miRNAs. Extracellular miRNAs may be found as soluble (free and EV cargo) and protein complexes.

Clinical significance of miRNAs in autoimmunity

MicroRNAs (miRNAs) are evolutionally conserved, single-stranded RNAs that regulate gene expression at the posttranscriptional level by disrupting translation. MiRNAs are key players in variety of biological processes that regulate the differentiation, development and activation of immune cells in both innate and adaptive immunity. The disruption and dysfunction of miRNAs can perturb the immune response, stimulate the release of inflammatory cytokines and initiate the production of autoantibodies, and contribute to the pathogenesis of autoimmune diseases, including systemic lupus erythmatosus (SLE), rheumatoid arthritis (RA), primary biliary cholangitis (PBC), and multiple sclerosis (MS). Accumulating studies demonstrate that miRNAs, which can be collected by noninvasive methods, have the potential to be developed as diagnostic and therapeutic biomarkers, the discovery and validation of which is essential for the improvement of disease diagnosis and clinical monitoring. Recently, with the development of detection tools, such as microarrays and NGS (Next Generation Sequencing), large amounts of miRNAs have been identified and suggest a critical role in the pathogenesis of autoimmune diseases. Several miRNAs associated diagnostic biomarkers have been developed and applied clinically, though the pharmaceutical industry is still facing challenges in commercialization and drug delivery. The development of miRNAs is less advanced for autoimmune diseases compared with cancer. However, drugs that target miRNAs have been introduced as candidates and adopted in clinical trials. This review comprehensively summarizes the differentially expressed miRNAs in several types of autoimmune diseases and discusses the role and the significance of miRNAs in clinical management. The study of miRNAs in autoimmunity promises to provide novel and broad diagnostic and therapeutic strategies for a clinical market that is still in its infancy.

Relationship between miR-155 and miR-146a polymorphisms and susceptibility to multiple sclerosis in an Egyptian cohort

Multiple sclerosis (MS) is an autoimmune disorder of the central nervous system. It was previously demonstrated that miR-155 and miR-146a served a vital role in the pathophysiology of MS, and single nucleotide polymorphisms in miR-155 and miR-146a were found to be associated with the susceptibility to different autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis and type I diabetes. The aim of the present study was to analyze the association between susceptibility to MS and two genetic polymorphisms (miR-155 rs767649 A>T and miR-146a rs57095329 A>G) in a cohort of Egyptian patients. The presence of the two polymorphisms were analyzed in 114 patients with MS and 152 healthy controls using quantitative PCR. The present study demonstrated for the first time that: The TT genotype and T allele in miR-155 (rs767649 A>T) polymorphism were associated with an increased risk of MS; the miR-146a (rs57095329 A>G) mutated G allele conferred protection against the development of MS in all genetic models; miR-155 rs767649 A>T was a risk associated polymorphism of MS in females, but not in males; and miR-155 rs767649 AT/TT and miR-146a rs57095329 GG genotypes showed significantly higher distributions among patients with higher Expanded Disability Status Scale scores and secondary progressive MS subgroups. Therefore, miR-155 rs767649 polymorphism may confer susceptibility to MS, whereas miR-146a rs57095329 may be protective against MS in an Egyptian cohort.

The Protective Effect of Bosentan against Atherosclerosis in Apolipoprotein E-Deficient Mice Is Mediated by miRNA-21

Vascular calcification is an independent risk factor for plaque instability and is associated with endothelial cell function. Here, we investigated the role of endothelial cell function in the calcification of atherosclerotic plaques. We hypothesized that atherosclerosis would be associated with endothelial dysfunction and that bosentan (Tracleer®), a dual endothelin-receptor antagonist, would preserve endothelial cell function in an apolipoprotein E-deficient (ApoE^-/-) mouse model of atherosclerosis. Accordingly, 4-6-week-old ApoE^-/- mice were fed a high-fat diet and treated with bosentan, and the effects of this treatment on body weight and blood lipid concentrations was evaluated. Endothelial damage in the aortic arch was assessed immunohistochemically to detect the proapoptotic proteins PDCD4, caspase-3, and Bax and the antiapoptotic protein Bcl-2. Notably, bosentan treatment was associated with decreased concentrations of these proteins and of blood lipids in ApoE^-/- mice. Consistent with these findings, we observed increased concentrations of miRNA-21 and PDCD4 mRNA expression in the aortic arch endothelium after bosentan treatment. We conclude that bosentan can prevent endothelial cell death and protect against atherosclerosis in ApoE-deficient mice by upregulating miRNA-21.

Comparison of The Expression of miR-326 between Interferon beta Responders and Non-Responders in Relapsing-Remitting Multiple Sclerosis

Objective

Multiple sclerosis (MS) is an inflammatory disease resulting in demyelination of the central nervous system (CNS). T helper 17 (Th17) subset protects the human body against pathogens and induces neuroinflammation, which leads to neurodegeneration. MicroRNAs (miRNAs) are a specific class of small (~22 nt) non-coding RNAs that act as post-transcriptional regulators. The expression of the miR-326 is highly associated with the pathogenesis of MS disease in patients through the promotion of Th17 development. Recently, studies showed that disease-modifying therapies (DMTs) could balance the dysregulation of miRNAs in the immune cells of patients with relapsing-remitting MS (RRMS). Interferon-beta (IFN-β) has emerged as one of the most common drugs for the treatment of RR-MS patients. The purpose of this study was to evaluate the expression of the miR-326 in RRMS patients who were responders and non- responders to IFN-β treatment.

Materials and Methods

In this cross-sectional study, a total of 70 patients (35 responders and 35 non-responders) were enrolled. We analyzed the expression of the miR-326 in peripheral blood mononuclear cells (PBMCs) of RRMS patients at least one year after the initiation of IFN-β therapy. Real-time polymerase chain reaction (RT-PCR) was applied to measure the expression of the miR-326.

Results

The results showed no substantial change in the expression of the miR-326 between responders and non- responders concerning the treatment with IFN-β. Although the expression of the miR-326 was slightly reduced in IFN-β-responders compared with IFN-β-non-responders; however, the reduction of the miR-326 was not statistically significant.

Conclusion

Overall, since IFN-β doesn’t normalize abnormal expression of miR-326, this might suggest that IFN-β affects Th17 development through epigenetic mechanisms other than miR-326 regulation.

MicroRNA-138 attenuates myocardial ischemia reperfusion injury through inhibiting mitochondria-mediated apoptosis by targeting HIF1-α

Myocardial ischemia-reperfusion (I/R) injury is considered to have a detrimental role in coronary heart disease, which is considered to be the leading cause of death worldwide. However, the molecular mechanism involved in the progression of myocardial I/R injury is still unclear. The current study aimed to investigate the expression and function of microRNA (miR)-138 in the process of myocardial I/R injury. First, miR-138 expression levels were analyzed both in myocardium with I/R injury and control myocardium using reverse transcription-quantitative polymerase chain reaction analysis. Then, the relationship between the levels of miR-138 and hypoxia-inducible factor (HIF)1-α was also investigated using a luciferase reporter assay. Assessment of myocardial infarct size, measurements of serum myocardial enzymes and electron microscopy analysis were all utilized to analyse the effect of miR-138 on myocardial I/R injury. The authors of current study also used western blotting to examine the expression levels of the mitochondrial fission-related proteins dynamin-1-like protein and mitochondrial fission 1 protein. It was found that miR-138 is downregulated and HIF1-α is upregulated after myocardial ischemia reperfusion injury. Overexpression of miR-138 reduced myocardial I/R injury-induced infarct sizes and myocardial enzyme levels, and it also inhibited the expression of proteins related to mitochondrial morphology and myocardial I/R-induced mitochondrial apoptosis by targeting HIF1-α. Taken together, these findings provide a novel insight into the molecular mechanism of miR-138 and HIF1-α in the progression of myocardial I/R injury. miR-138 has the potential to become a promising therapeutic target for treating myocardial I/R injury.

Metabolism and Autoimmune Responses: The microRNA Connection

Distinct metabolic pathways are known to regulate growth, differentiation, survival, and activation of immune cells by providing energy and specific biosynthetic precursors. Compelling experimental evidence demonstrates that effector T cell functions are coupled with profound changes in cellular metabolism. Importantly, the effector T cell-dependent “anti-self” response characterizing the autoimmune diseases is accompanied by significant metabolic alterations. MicroRNAs (miRNAs), evolutionary conserved small non-coding RNA molecules that affect gene expression by binding to target messenger RNAs, are now known to regulate multiple functions of effector T cells, including the strength of their activation, thus contributing to immune homeostasis. In this review, we will examine the most recent studies that describe miRNA direct involvement in the metabolic reprogramming that marks effector T cell functions. In particular, we will focus on the work showing a connection between miRNA regulatory function and the molecular network dysregulation that leads to metabolic pathway derangement in autoimmunity. Finally, we will also speculate on the possibility that the interplay between miRNAs and metabolism in T cells may help identify novel miRNA-based therapeutic strategies to treat effector T cell immunometabolic alterations in pathological conditions such as autoimmunity and chronic inflammation.

The Missing Link: How Exosomes and miRNAs can Help in Bridging Psychiatry and Molecular Biology in the Context of Depression, Bipolar Disorder and Schizophrenia

MicroRNAs (miRNAs) only recently have been recognized as promising molecules for both fundamental and clinical neuroscience. We provide a literature review of miRNA biomarker studies in three most prominent psychiatric disorders (depression, bipolar disorder and schizophrenia) with the particular focus on depression due to its social and healthcare importance. Our search resulted in 191 unique miRNAs across 35 human studies measuring miRNA levels in blood, serum or plasma. 30 miRNAs replicated in more than one study. Most miRNAs targeted neuroplasticity and neurodevelopment pathways. Various limitations do not allow us to make firm conclusions on clinical potential of studied miRNAs. Based on our results we discuss the rationale for future research investigations of exosomal mechanisms to overcome methodological caveats both in studying etiology and pathogenesis, and providing an objective back-up for clinical decisions.

Dietary Modulation of Intestinal Microbiota: Future Opportunities in Experimental Autoimmune Encephalomyelitis and Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune disease that affects the functioning of the central nervous system (CNS). Recent studies on MS and its animal model, experimental autoimmune encephalomyelitis (EAE), have shown that the composition and abundance of microbes in the intestinal microbiota are an environmental risk factor for the development of MS and EAE. Changes in certain microbial populations in the gastrointestinal tract can cause MS in humans, but MS inflammation can be reduced or even prevented by introducing other commensal microbes that produce beneficial metabolites. Other risk factors for MS include the presence of an altered gut physiology and the interaction between the intestinal microbiota and the immune system. Metabolites including short-chain fatty acids (SCFAs), such as butyrate, are the primary signaling molecules produced by the intestinal microbiota that interact with the host immune system, suggesting an association between MS pathophysiology and gut microbiota. In addition, several host microRNAs present in the gut have been found to interact with the intestinal microbial community, these interactions may indirectly affect the neurological system. Increasing evidence has shown that regulation of the intestinal microbiota is an important approach for reducing MS inflammation. Thus, here we review the use of diet to alter the gut microbiota and its application in the treatment and prevention of MS.

Complex regulation of ecto-5'-nucleotidase/CD73 and A2AR-mediated adenosine signaling at neurovascular unit: A link between acute and chronic neuroinflammation

The review summarizes available data regarding the complex regulation of CD73 at the neurovascular unit (NVU) during neuroinflammation. Based on available data we propose the biphasic pattern of CD73 regulation at NVU, with an early attenuation and a postponed up-regulation of CD73 activity. Transient attenuation of CD73 activity on leukocyte/vascular endothelium and leukocyte/astrocyte surface, required for the initiation of a neuroinflammatory response, may be effectuated either by catalytic inhibition of CD73 and/or by shedding of the CD73 molecule from the cell surface, while postponed induction of CD73 is effectuated by transcriptional up-regulation of Nt5e and posttranslational modifications. Neuroinflammatory conditions are also associated with significant enhancement and gain-of-function of A_2AR-mediated adenosine signaling. However, in contrast to the temporary prevalence of A_2AR over A₁R signaling during an acute inflammatory response, prolonged induction of A_2AR and resulting perpetual CD73/A_2AR coupling may be a contributing factors in the transition between acute and chronic neuroinflammation. Thus, pharmacological targeting of the CD73/A_2AR axis may attenuate inflammatory response and ameliorate neurological deficits in chronic neuroinflammatory conditions.

Epstein-Barr Virus and miRNAs: Partners in Crime in the Pathogenesis of Multiple Sclerosis?

MicroRNAs (miRNAs) are small non-coding RNAs that modulate gene expression post transcriptionally. In healthy individuals, miRNAs contribute to maintaining gene expression homeostasis. However, the level of miRNAs expressed is markedly altered in different diseases, including multiple sclerosis (MS). The impact of such changes is being investigated, and thought to shape the immune system into the inflammatory autoimmune phenotype. Much is yet to be learned about the contribution of miRNAs in the molecular pathology of MS. Epstein-Barr virus (EBV) infection is a major risk factor for the development of MS. EBV encodes more than 40 miRNAs, most of which have been studied in the context of EBV associated cancers. These viral miRNAs regulate genes involved in cell apoptosis, antigen presentation and recognition, as well as B cell transformation. If EBV infection contributes to the pathology of MS, it is plausible that EBV miRNAs may be involved. Unfortunately, there are limited studies addressing how EBV miRNAs are involved in the pathogenesis of MS. This review summarizes what has been reported regarding cellular and viral miRNA profiles in MS and proposes possible interactions between the two in the development of MS.

Aberrant expression of microRNA in CD4+ cells contributes to Th17/Treg imbalance in primary immune thrombocytopenia

INTRODUCTION

Imbalance of T helper 17 (Th17) cells and regulatory T (Treg) cells occurs in primary immune thrombocytopenia (ITP), but the mechanism remains unclear. We investigated whether expression of microRNAs (miRNAs) related to helper T or Treg cells regulate the Th17/Treg ratio in CD4⁺ T cells.

MATERIALS AND METHODS

Peripheral blood was obtained from 52 active ITP patients and 56 healthy controls. We detected miRNA expression using RT-PCR with stem-loop primers and U6 as control.Th17 and Treg percentages were analyzed by flow cytometry. CD4⁺ cells were transfected with miRNA (miR-99a, miR-182-5p, miR-183-5p) mimics or inhibitors to investigate their function.

RESULTS

miR-99a expression in CD4⁺ cells in ITP patients was lower than in controls, while expression of miR-182-5p and miR-183-5p were higher in ITP patients. Moreover, Treg percentage correlated positively with miR-99a expression in ITP patients. We found no significant correlation between Th17 percentage and miR-182-5p or miR-183-5p expression. miR-183-5p expression correlated negatively with platelet count, while we found no significant difference between platelet count and miR-99a or miR-182-5p. miR-183-5p expression in CD4⁺ T cells from severe patients was significantly higher than in those from non-severe patients. Furthermore, down-regulating miR-183-5p expression repressed Th17 differentiation, while up-regulating miR-99a increased Tregs detected in CD4⁺ cells from ITP patients. In addition, up-regulated miR-99a repressed mTOR and p-mTOR expression.

CONCLUSIONS

miR-99a, miR-182-5p, and miR-183-5p expression levels in CD4⁺ cells were abnormal in ITP patients. Aberrant expression of miRNAs may contribute to the Th17/Treg imbalance in ITP patients and may represent a novel therapeutic target.

MicroRNA-140 attenuates myocardial ischemia-reperfusion injury through suppressing mitochondria-mediated apoptosis by targeting YES1

Myocardial ischemia-reperfusion (I/R) injury is thought to have its detrimental role in coronary heart disease (CHD), which is considered as the foremost cause of death all over the world. However, molecular mechanism in the progression of myocardial I/R injury is still unclear. The goal of this study was to investigate the expression and function of microRNA-140 (miR-140) in the process of myocardial I/R injury. The miR-140 expression level was analyzed in the myocardium with I/R injury and control myocardium using quantitative real-time polymerase chain reaction. Then the relation between the level of miR-140 and YES proto-oncogene 1 (YES1) was also investigated via luciferase reporter assay. Assessment of myocardial infarct size measurement of serum myocardial enzymes and electron microscopy analysis were used for analyzing the effect of miR-140 on myocardial I/R injury. We also used Western blot analysis to examine the expression levels of the mitochondrial fission-related proteins, Drp1 and Fis1. miR-140 is downregulated, and YES1 is upregulated after myocardial I/R injury. Overexpression of miR-140 could reduce the increase related to myocardial I/R injury in infarct size and myocardial enzymes, and it also could inhibit the expression of proteins related to mitochondrial morphology and myocardial I/R-induced mitochondrial apoptosis by targeting YES1. Taken together, these findings may provide a novel insight into the molecular mechanism of miR-140 and YES1 in the progression of myocardial I/R injury. MiR-140 might become a promising therapeutic target for treating myocardial I/R injury.