MicroRNAs-mediated regulation pathways in rheumatic diseases.

Rheumatoid arthritis (RA) and ankylosing spondylitis (AS) are two common rheumatic disorders marked by persistent inflammatory joint disease. Patients with RA have osteodestructive symptoms, but those with AS have osteoproliferative manifestations. Ligaments, joints, tendons, bones, and muscles are all affected by rheumatic disorders. In recent years, many epigenetic factors contributing to the pathogenesis of rheumatoid disorders have been studied. MicroRNAs (miRNAs) are small, non-coding RNA molecules implicated as potential therapeutic targets or biomarkers in rheumatic diseases. MiRNAs play a critical role in the modulation of bone homeostasis and joint remodeling by controlling fibroblast-like synoviocytes (FLSs), chondrocytes, and osteocytes. Several miRNAs have been shown to be dysregulated in rheumatic diseases, including miR-10a, 16, 17, 18a, 19, 20a, 21, 27a, 29a, 34a, 103a, 125b, 132, 137, 143, 145, 146a, 155, 192, 203, 221, 222, 301a, 346, and 548a.The major molecular pathways governed by miRNAs in these cells are Wnt, bone-morphogenic protein (BMP), nuclear factor (NF)-κB, receptor activator of NF-κB (RANK)-RANK ligand (RANKL), and macrophage colony-stimulating factor (M-CSF) receptor pathway. This review aimed to provide an overview of the most important signaling pathways controlled by miRNAs in rheumatic diseases.

Immune-related adverse events (irAEs) in ankylosing spondylitis (AS) patients treated with interleukin (IL)-17 inhibitors: a systematic review and meta-analysis.

BACKGROUND: Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease characterized by immune system dysregulation and inflammation in the joints. Interleukin (IL)-17 inhibitors are new biological drugs used to treat AS. In this study, we aimed to assess the risk of immune system-related AEs due to targeting IL-17 or IL-17R. METHODS: The CENTRAL, PubMed, Scopus, Google Scholar, Clinical Trials Registry, and ICTRP were searched for randomized clinical trials (RCTs) and non-RCTs until February 2021. The risk of irAEs in patients treated with IL-17 inhibitors compared to the placebo or a drug-free control was evaluated. In studies that reported AEs of the IL-17 inhibitors at several different time points, we compared the number of cases/100 patient-year in which irAEs were reported. Subgroup analyses were also performed based on the dose and type of drugs. RESULTS: Thirteen studies of 1848 AS patients treated by IL-17 inhibitors (secukinumab, ixekizumab, bimekizumab, and netakimab) and 764 participants who received a placebo were included. The risk of some AEs related to immune function in patients under IL-17 inhibitors treatment was significantly higher than that of the placebo group, including infection and infestation (risk difference RD = 0.09, P = 0.02), nasopharyngitis (RD = 0.04, P < 0.001), opportunistic infections (RD = 0.01, P = 0.04), and neutropenia (RD = 0.04, P = 0.03). Besides, the results of the Cochran Q test showed that there were significant differences between the occurrence of some AEs over time, including infection and infestations (p < 0.001, RCTs), upper respiratory tract infections (p < 0.001, non-RCTs), urinary tract infections (p < 0.001, non-RCTs), and diarrhea (p < 0.01, RCTs). CONCLUSIONS: The most common immune system-related AEs in patients treated with IL-17 inhibitors are mucosal and opportunistic infections.

Regulatory T cells for amyotrophic lateral sclerosis/motor neuron disease: A clinical and preclinical systematic review.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by neuronal degeneration and inflammation in the nerves. The role of the immune system has been concentrated by researchers in the etiopathogenesis of the disease. Given the inhibitory roles of regulatory T cells (Tregs), it is expected that increasing or activating their populations in patients with ALS can have significant therapeutic effects. Here we searched databases, including CENTRAL, MEDLINE, CINAHL Plus, clinicaltrials.gov, and ICTRP for randomized clinical trials (RCTs) and non-RCTs until March 2019. For preclinical studies, we searched PubMed, Scopus, and Google Scholar up to June 2019. We also included preclinical studies, due to the lack of clinical information available, which used Tregs (or directly targeting them) for treating mice models of ALS. We identified 29 records (CENTRAL 7, MEDLINE 4, CINAHL Plus 8, and clinicaltrials.gov 10) and removed 10 duplicated publications. After screening, we identified one RCT which had been published as an abstract, three non-RCTs, and four ongoing studies. We also identified 551 records (PubMed 446, Google Scholar 68, and Scopus 37) for preclinical studies and performed a meta-analysis. Finally, we found three papers that matched our inclusion criteria for preclinical studies. Results indicated the effectiveness of the application of Tregs in the treatment of ALS. Our meta-analysis on preclinical studies revealed that Tregs significantly prolonged survival in mice models of ALS. Overall, our analysis testified that exertion of Tregs in the treatment of ALS is a promising approach, that notwithstanding, requires further evaluations.

Effective delivery of anti-PD-L1 siRNA with human heavy chain ferritin (HFn) in acute myeloid leukemia cell lines.

Because of the high biocompatibility, self-assembly capability, and CD71-mediated endocytosis, using human heavy chain ferritin (HFn) as a nanocarrier would greatly increase therapeutic effectiveness and reduce possible adverse events. Anti-PD-L1 siRNA can downregulate the level of PD-L1 on tumor cells, resulting in the activation of effector T cells against leukemia. Therefore, this study aimed to produce the tumor-targeting siPD-L1/HFn nanocarrier. Briefly, the HFn coding sequence was cloned into a pET-28a, and the constructed expression plasmid was subsequently transformed into E. coli BL21. After induction of Isopropyl ß-D-1-thiogalactopyranoside (IPTG), HFn was purified with Ni-affinity chromatography and dialyzed against PBS. The protein characteristics were analyzed using SDS-PAGE, Western Blot, and Dynamic light scattering (DLS). The final concentration was assessed using the Bicinchoninic acid (BCA) assay. The encapsulation was performed using the standard pH system. The treatment effects of siPD-L1/HFn were carried out on HL-60 and K-562 cancer cell lines. The RT-PCR was used to determine the mRNA expression of PD-L1. The biocompatibility and excretion of siPD-L1/HFn have also been evaluated. The expression and purity of HFn were well verified through SDS-PAGE, WB, and DLS. RT-PCR analyses also showed significant siRNA-mediated PD-L1 silencing in both HL-60 and K-562 cells. Our study suggested a promising approach for siRNA delivery. This efficient delivery system can pave the way for the co-delivery of siRNAs and multiple chemotherapies to address the emerging needs of cancer combination therapy.

Comparison of the efficacy of combined budesonide and fexofenadine versus combined fluticasone propionate and fexofenadine on the expression of class-4 semaphorins and their receptors in the peripheral blood cells of patients with allergic rhinitis.

Background: Allergic rhinitis (AR) is a common immunoglobulin (Ig) E-mediated disease. This study aimed to evaluate the gene expression levels of class 4 semaphorins and their receptors in AR patients before and after treatment with budesonide and fexofenadine (B/F) compared to fluticasone propionate and fexofenadine (FP/F). Methods: In this study, 29 AR patients (age 34.4 ± 1.2 years, 18 men and 11 women) were treated with B/F, and 24 AR patients (age 32.8 ± 1.9 years, 15 men and 9 women) were treated with FP/F for one month. Before and after treatment, peripheral blood samples were taken from patients. The expression levels of SEMA4A, SEMA4C, SEMA4D, Plexin-B2, and Plexin-D1 genes were measured using the qPCR method. In addition, the serum levels of IgE were measured using an enzyme-linked immunosorbent assay (ELISA). Results: The expression levels of SEMA4A (P = 0.011), 4C (P = 0.017), Plexin-B2 (P = 0.0005), and Plexin-D1 (P = 0.008) remarkably increased in AR patients treated with B/F. Our results show a significant reduction in the gene expression levels of SEMA4A (P = 0.002), 4C (P = 0.014), 4D (P = 0.003), Plexin-B2 (P = 0.033), and Plexin-D1 (P = 0.035) after treatment with FP/F. The serum levels of IgE increased in FP/F treated group (P = 0.017) and conversely decreased in the treated group with B/F (P = 0.019). Moreover, the percentages of eosinophils were reduced in both FP/F and B/F groups (P = 0.015 and P = 0.0001, respectively). Conclusion: In conclusion, concomitant use of fexofenadine and fluticasone propionate reduced SEMA4A, 4C, 4D, Plexin-B2, and Plexin-D1, while the SEMA4A, 4C, Plexin-B2, and Plexin-D1 gene expression levels were increased in the patient group treated with B/F.

Dimethyl Fumarate Inhibits Fibroblast Like Synoviocytes-mediated Inflammation and Joint Destruction in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) as a chronic inflammatory disorder affects around 1% of the world population. Fibroblast-like synoviocyte (FLS), one of the main cells in RA pathogenesis is characterized by hyperproliferation and resistance to apoptosis resulting to synovial hyperplasia. Dimethyl fumarate (DMF) has been licensed for the treatment of multiple sclerosis (MS) and psoriasis; however, its role in RA is unknown. DMF has immunomodulatory properties and may be considered as therapeutic approach in RA treatment. In this study, we aimed to investigate the effect of DMF on controlling FLS-mediated synovial inflammation and joint destruction in RA. FLSs were isolated from synovial tissues of 8 patients with RA and treated with DMF. Apoptosis rate was analyzed by Annexin V-FITC. Cell proliferation was measured by carboxyfluorescein succinimidyl ester (CFSE) dye. The matrix metalloproteinase 3 (MMP3) and NF-кB pathway protein (p65) mRNA expression were evaluated by RT-PCR. Also, the IL-6 production and lactate release were measured in FLS supernatant. DMF treatment decreased the cell proliferation and increased apoptosis in a dose dependent manner. DMF-treated FLS showed a reduction in IL-6 and lactate release. Moreover, it was revealed that DMF inhibited the expression of p65 and MMP3. Our data demonstrate that DMF treatment suppresses the aggressive and inflammatory features of RA FLSs. Our Results suggest that DMF might be expected to be evaluated as a therapy for RA.

Dysregulation of Long Noncoding RNA NEAT1/miR-199a-5/BiP Axis in Patients with Diabetic Neuropathy.

OBJECTIVE: Diabetic neuropathy (DN) is a type of nerve damage and the most common complication of diabetes. Regarding the association between endoplasmic reticulum (ER) stress with the pathogenesis of neuropathy, this study aims to examine binding immunoglobulin protein (BiP) gene expression and long noncoding RNA nuclear enriched abundant transcript 1 (NEAT1), miR-199a-5 as its regulator in the peripheral blood of DN patients compared to diabetic patients without neuropathy. METHODS: Peripheral blood samples were obtained from DN (n = 20) patients and diabetic patients without neuropathy (non-DN) (n = 20). After RNA extraction from peripheral blood mononuclear cells, reverse transcription-quantitative polymerase chain reaction was performed to evaluate RNA expression. RESULTS: The results showed that the expression level of NEAT1 and BiP genes in the DN group increased significantly compared to the non-DN group. Also, the expression level of miR-199a-5p in the DN group was significantly downregulated. CONCLUSION: As a result, the axis of NEAT1, miR-199a-5p, and BiP may have a role in the DN pathogenesis.

Upregulation of Unfolded Protein Response and ER Stress-Related IL-23 Production in M1 Macrophages from Ankylosing Spondylitis Patients.

The inflammatory interleukin (IL)-23/IL-17 axis plays an important role in the pathogenesis of ankylosing spondylitis (AS), but with an unknown regulatory mechanism. This study aimed to investigate the role of endoplasmic reticulum (ER) stress and autophagy pathway in the expression of IL-23 in peripheral blood-derived macrophages in AS patients. Peripheral blood samples were obtained from 15 AS and 15 healthy control subjects. MACS was used to isolate monocytes from PBMCs. Then, M-CSF was used to differentiate monocytes to M2 macrophages. IFN-γ and/or LPS were used to activate macrophages and M2 polarization towards M1 macrophages. Thapsigargin was used to induce ER stress and 3-MA to inhibit autophagy. The purity of extracted monocytes and macrophage markers was evaluated by flow cytometry. mRNA expression of HLA-B and-B27, ER stress-related genes, autophagy-related genes, and IL-23p19 was performed using RT-qPCR. Soluble levels of IL-23p19 were measured using ELISA. Significant increase in mRNA expression of HLA-B, HLA-B27, BiP, XBP1, CHOP, and PERK mRNAs was observed in macrophages of AS patients before and after stimulation with IFN-γ and LPS. No significant change in autophagy gene expression was detected. mRNA and soluble levels of IL-23p19 demonstrated a significant increase in macrophages of AS patients compared to healthy subjects. ER stress induction led to a significant increase in IL-23p19 in macrophages. Inhibition of autophagy did not affect IL-23 expression. ER stress, unlike autophagy, is associated with increased IL-23 levels in macrophages of AS patients.Key Messages ER stress in macrophages from AS patients plays a role in the increased production of IL-23. The autophagy pathway is not involved in the modulation of IL-23 production by AS macrophages.

The MALAT1-H19/miR-19b-3p axis can be a fingerprint for diabetic neuropathy.

BACKGROUND: Diabetic neuropathy (DN) is one of the most common microvascular complications of diabetes that is attributed to impaired immune regulation. In this study, we first examined the expression of long non-coding (lncRNAs) MALAT1 and H19, and their downstream microRNAs (miRNAs) miR-19b-3p, miR-125a-5p, and then assayed the mRNA expression of downstream targets of these miRNAs, including SEMA4C, SEMA4D, PLXNB2, ATG14, and ATG16L1. METHODS: Peripheral blood samples were obtained from 20 DN patients, 20 diabetic patients without neuropathy (non-DN), and 10 healthy controls (HC). The expression levels of lncRNAs, miRNAs, and target genes were evaluated in whole blood using Real-time PCR. RESULTS: Upregulation of MALAT1, H19, SEMA4C, PLXNB2, and ATG16L1 and downregulation of miR-19b-3p was seen in the DN group compared to the non-DN and HC groups. Non-DN patients had significantly lower expression levels of miR-125a-5p, SEMA4D, ATG14, and ATG16L1 compared to the HC. MALAT1 and H19 had a positive correlation with each other and had a negative correlation with the expression of miR-19b-3p. Expression levels of SEMA4C, SEMA4D, PLXNB2, and ATG16L1 were positively correlated with each other as well as lncRNAs expression. Receiver operating characteristic (ROC) analysis showed Area under the curve (AUC) = 0.9226 for MALAT1, AUC= 0.9248 for H19, and AUC= 0.7683 for miR-19b-3p. CONCLUSION: The MALAT1-H19/miR-19b-3p axis might be involved in the development of DN and these molecules could be useful biomarkers for DN. Dysregulated expression of SEMA4C, PLXNB2, and ATG16L1, targeted by miR-19b-3p and miR-125a-5p, showed that they probably play a role in the DN development.

The axis of long non-coding RNA MALAT1/miR-1-3p/CXCR4 is dysregulated in patients with diabetic neuropathy.

Background: Diabetic neuropathy (DN) is a prevalent complication of diabetes mellitus characterized by pain and inflammation. Long non-coding RNAs (lncRNAs) have been associated with DN. This study aimed to investigate transcript levels of Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), microRNA (miR)-1-3p, and C-X-C motif chemokine receptor 4 (CXCR4) in the DN patients and type 2 diabetes mellitus (T2DM) cases without neuropathy. Methods: Here, 20 cases with DN and 20 T2DM subjects without neuropathy (as the control group) were included. Total RNA was extracted from peripheral blood mononuclear cells (PBMCs) of all participants. The expression levels of targets were evaluated by Real-time-PCR. Results: Results showed that MALAT1 (Fold change = 2.47, P = 0.03) and CXCR4 (Fold change = 1.65, P = 0.023) were significantly upregulated, while miR-1-3p was downregulated (Fold change = 0.9, P = 0.028) in whole blood samples from DN patients compared to the control group. A significant correlation was found between transcript levels of MALAT1 and CXCR4 (rho = 0.84; P < 0.0001). Conclusions: This study suggests a possible involvement of the MALAT1/miR-1-3p/CXCR4 axis in the pathogenesis of DN.

The role of immune semaphorins in the pathogenesis of multiple sclerosis: Potential therapeutic targets.

The immune and nervous systems possess a highly intricate network of synaptic connections, shared messenger molecules, and exquisite communication ways, allowing intercellular signal transduction. The semaphorins (Semas) were initially identified as axonal guidance molecules in the development of the nervous system but later were found to be implicated also in regulating the immune system, known in this case as the "immune Semas" or "immunoregulatory Semas". Increasingly, these molecules are involved in multiple aspects of both physiological and pathological immune responses and were recently indicated to take part in various immunological disorders, encompassing allergy, cancer, and autoimmunity. Semas transduce signals by connecting to their cognate receptors, namely, plexins and neuropilins. Some of them, like Sema-3F, have been found to function as the inducer of the remyelination process whereas some others, like Sema-3A and Sema-4D, act to inhibit this process, either directly or indirectly. Besides, Sema-4A is crucial to the differentiation of T helper type 1 (Th1) and Th17 cells that are potentially involved in the pathogenesis of multiple sclerosis (MS), an autoimmune disease of the central nervous system. This review aims to reveal the role of immune Semas in the pathogenesis of MS and its animal model, experimental autoimmune encephalomyelitis, focusing on the therapeutic usages of these molecules to treat this neurodegenerative disease.

Advanced glycation end products (AGEs) and its receptor, RAGE, modulate age-dependent COVID-19 morbidity and mortality. A review and hypothesis.

Coronavirus Disease 2019 (COVID-19), caused by the novel virus SARS-CoV-2, is often more severe in older adults. Besides age, other underlying conditions such as obesity, diabetes, high blood pressure, and malignancies, which are also associated with aging, have been considered risk factors for COVID-19 mortality. A rapidly expanding body of evidence has brought up various scenarios for these observations and hyperinflammatory reactions associated with COVID-19 pathogenesis. Advanced glycation end products (AGEs) generated upon glycation of proteins, DNA, or lipids play a crucial role in the pathogenesis of age-related diseases and all of the above-mentioned COVID-19 risk factors. Interestingly, the receptor for AGEs (RAGE) is mainly expressed by type 2 epithelial cells in the alveolar sac, which has a critical role in SARS-CoV-2-associated hyper inflammation and lung injury. Here we discuss our hypothesis that AGEs, through their interaction with RAGE amongst other molecules, modulates COVID-19 pathogenesis and related comorbidities, especially in the elderly.

Determination of the transcriptional level of long non-coding RNA NEAT-1, downstream target microRNAs, and genes targeted by microRNAs in diabetic neuropathy patients.

BACKGROUND: Diabetic neuropathy (DN) is one of the microvascular complications of diabetes that leads to peripheral sensorimotor and autonomic nervous system damages. In this study, we first examined the expression of lncRNA NEAT-1 and its downstream microRNAs, miR-183-5p, miR-433-3p, and then examined mRNA expression of ITGA4, ITGB1, SESN1, and SESN3 as the downstream targets of miR-183-5p, miR-433-3p. METHODS: The blood sample was obtained from a total of 40 patients with type 2 diabetes (20 DN patients and 20 non-DN diabetic cases) and ten healthy individuals. After RNA extraction from peripheral blood samples and cDNA synthesis, expression measurements were performed by the RT-qPCR technique. RESULTS: Our results showed that the expression level of lncRNA NEAT-1 was significantly higher, and the expression level of miR-183-5p was significantly lower in DN patients compared to the healthy control group. Besides, the expression level of miR-433-3p was significantly lower, and the mRNA expression of ITGA4, SESN1, and SESN3 was significantly higher in DN patients compared to the diabetes group. The ROC curve analysis showed that the miR-183-5p with high levels of accuracy could discriminate DN patients from healthy control (AUC = 0.836) and NEAT-1, SESN1, SESN3, ITGA4 have a high ability to distinguish DN from non-DN patients (AUC = 0.701, 0.772, 0.815 and 0.780, respectively). CONCLUSION: It seems that the NEAT-1 probably targets miR-183-5p and miR-433-3p, as a result of which the expression of ITGA4, SESN1, and SESN3 is affected. Dysregulated expression of NEAT-1 and related miRNAs and genes might be involved in the pathogenesis of DN.

Immune semaphorins: Crucial regulatory signals and novel therapeutic targets in asthma and allergic diseases.

Asthma and allergic diseases are a group of chronic inflammatory disorders that arise as a result of excessive responses of the immune system against intrinsically harmless environmental substances. It is well known that substantial joint characteristics exist between the immune and nervous systems. The semaphorins (Semas) were initially characterized as axon-guidance molecules that play a crucial role during the development of the nervous system. However, increasing evidence indicates that a subset of Semas, termed "immune Semas", acting through their cognate receptors, namely, plexins (Plxns), and neuropilins (Nrps), also contributes to both physiological and pathological responses of the immune system. Notably, immune Semas exert critical roles in regulating a broad spectrum of biological processes, including immune cell-cell interactions, activation, differentiation, cell migration and mobility, angiogenesis, tumor progression, as well as inflammatory responses. Accumulating evidence indicates that the modification in the signaling of immune Semas could lead to various immune-mediated inflammatory diseases, ranging from cancer to autoimmunity and allergies. This review summarizes the recent evidence regarding the role of immune Semas in the pathogenesis of asthma and allergic diseases and discusses their therapeutic potential for treating these diseases.

Semaphorin 4A, 4C, and 4D: Function comparison in the autoimmunity, allergy, and cancer.

Semaphorins are a group of proteins that are divided into eight subclasses and identified by a conserved Sema domain on their carboxyl terminus. Sema4A, 4C, and 4D are the members of the fourth class of semaphorin family, which are known as membrane semaphorins; however, these molecules can be altered to soluble semaphorins by proteolytic cleavage. Semaphorins have various roles in the immune, nervous, and metabolic systems. In the immune system, these molecules contribute to the formation of cellular, humoral, and innate immune responses, such as inflammation, leukocyte migration, immunological synapse formation, and germinal center events. Given the diverse roles of semaphorins in the immune system, in this review, we have tried to give a comprehensive look at the role of these molecules in autoimmunity, allergy, and cancer. Sema4D and 4A seem to play a critical role in the pathogenesis of some autoimmune diseases, such as multiple sclerosis. In contrast, it has been shown that Sema4A and 4C have beneficial effects on allergies, and their absence can exacerbate the severity of the disease. In the case of cancer, an increase in all three of these molecules has been reported. Sema4D and 4C can contribute to tumor progression in human patients or experimental models, while the role of Sema4A has not yet been fully understood. In conclusion, semaphorins seem to be a favorable therapeutic target for autoimmune diseases and allergies. However, in cancer, studies have not yet been able to identify the exact role of semaphorins, and further studies are needed.

The role of myeloid-derived suppressor cells in the pathogenesis of rheumatoid arthritis; anti- or pro-inflammatory cells?

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of the immature myeloid cells that are derived from the myeloid progenitors with immunosuppressive functions. MDSCs are accumulated in the inflammatory sites during some autoimmune disorders, such as rheumatoid arthritis (RA) and can be an important factor in the pathogenesis of these diseases. Some research has shown the anti-inflammatory role of MDSCs during the RA progression and supports the hypothesis that MDSCs can be a potential treatment option for autoimmunity with their immunosuppressive activity. In contrast, some papers have reported the opposite effects of MDSCs, and support the hypothesis that MDSCs have a pro-inflammatory role in autoimmune disease. MDSCs functions in RA have not been fully understood, and some controversies, as well as many unanswered questions, remain. Although the two well-known subgroups of MDSCs, M-MDSC, and PMN-MDSC, seem to have different suppressive functions and regulate the immune system responses in a different manner; some studies have shown these cells are converted to each other and even to other cells under different pathological conditions. This review summarises some of the latest papers with respect to the MDSCs functions and discusses the relationship between MDSCs and inflammation in the context of rheumatoid arthritis.