MicroRNA-17-5p Reduces Inflammation and Bone Erosions in Mice With Collagen-Induced Arthritis and Directly Targets the JAK/STAT Pathway in Rheumatoid Arthritis Fibroblast-like Synoviocytes

Suberosin attenuates rheumatoid arthritis by repolarizing macrophages and inhibiting synovitis via the JAK/STAT signaling pathway

BACKGROUND

Rheumatoid arthritis (RA) is a systemic disease that primarily manifests as chronic synovitis of the symmetric small joints. Despite the availability of various targeted drugs for RA, these treatments are limited by adverse reactions, warranting new treatment approaches. Suberosin (SBR), isolated from Plumbago zeylanica-a medicinal plant traditionally used to treat RA in Asia-possesses notable biological activities. This study aimed to investigate the effects and potential underlying pathways of SBR on RA.

METHODS

Tumor necrosis factor-alpha (TNF-α) induced inflammation in RA-derived fibroblast-like synoviocytes (RA-FLS), and the expression of proinflammatory mediators was assessed using q-RT PCR and ELISA after treatment with various SBR concentrations. Bone marrow-derived macrophages (BMDMs) were induced to differentiate into M1 and M2 macrophages, followed by treatment with various SBR concentrations and macrophage polarization assessment. Low-dose (0.5 mg/kg/d) and high-dose (2 mg/kg/d) SBR regimens were administered to a collagen-induced arthritis (CIA) mouse model for 21 days, and the anti-arthritic effects of SBR were evaluated. Network pharmacology and molecular docking analyses were used to predict the anti-arthritic targets of SBR. The effect of SBR on the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway was evaluated.

RESULTS

SBR suppressed macrophage polarization toward the M1 phenotype while enhancing their polarization toward the M2 phenotype. SBR reduced the levels of proinflammatory mediators in TNF-α-induced RA-FLS. Mechanistically, SBR inhibited the phosphorylation of the JAK1/STAT3 signaling pathway in RA-FLS and M1 macrophages and promoted the phosphorylation of the JAK1/STAT6 pathway in M2 macrophages, enhancing M2 polarization. In vivo, prophylactic treatment of low-dose SBR reduced M1 macrophage infiltration into synovial tissue, increased the proportion of M2 macrophages, and decreased the expression of inflammatory mediators in the serum and synovial tissue, alleviating synovial inflammation. SBR significantly alleviated arthritis in CIA mice through macrophage repolarization and inhibition of inflammation.

CONCLUSION

SBR significantly reduced clinical symptoms, joint pathological damage, and expression inflammatory cytokine expression in CIA mice. SBR exhibited anti-arthritic effects via the JAK1/STAT3 and JAK1/STAT6 signaling pathways, inhibiting synovial tissue inflammation and M1 macrophage polarization while promoting M2 macrophage polarization. Therefore, SBR may be an effective candidate for RA treatment.

Peficitinib suppresses diffuse-type tenosynovial giant cell tumor by targeting TYK2 and JAK/STAT signaling

Diffuse-type tenosynovial giant cell tumor (dTGCT) is a destructive but rare benign proliferative synovial neoplasm. Although surgery is currently the main treatment modality for dTGCT, the recurrence risk is up to 50%. Therefore, there is a great need for effective drugs against dTGCT with minor side effects. The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling plays a central role in rheumatoid arthritis (RA), a disease with similar characteristics as dTGCT, but its function in dTGCT remains unknown. dTGCT fibroblast-like synoviocytes (FLS) and macrophages were isolated from 10 synovial tissue samples from dTGCT patients for the screening and validation of the five clinically approved JAK inhibitors to treat RA against dTGCT. Cell viability, cell death, inflammation and the activity of the JAK family members of cultured dTGCT FLS (both 2-D and 3-D) and macrophages were investigated for the efficacy of the JAK inhibitors. Here, we found that similar to RA, JAK/STAT signaling was markedly activated in the dTGCT synovium. Of the 5 JAK inhibitors, peficitinib was shown to have the most potency in addressing some of the pathological responses of dTGCT FLS and macrophages. The potency of peficitinib was much higher than pexidartinib, which is the only FDA-approved drug for dTGCT. Mechanistically, peficitinib inhibited tyrosine kinase 2 (TYK2), a JAK family member necessary for the pathological progression of dTGCT FLS and macrophages. In summary, we not only revealed JAK/STAT (especially TYK2) signaling as the major mechanism underlying dTGCT, but also identified peficitinib as a promising drug against dTGCT.

Guggulsterone ameliorates psoriasis by inhibiting keratinocyte proliferation and inflammation through induction of miR-17 directly targeting JAK1 and STAT3

The pathogenesis of psoriasis involves hyperproliferation of epidermal keratinocytes and abnormal interactions between activated keratinocytes and infiltrating immune cells. Emerging evidence has shown that keratinocytes play essential roles in both the initiation and maintenance of psoriasis, suggesting that exposing keratinocytes to agents with antiproliferative and anti-inflammatory effects may be effective for psoriasis treatment. Guggulsterone (GS), a plant sterol derived from the gum resin of Commiphora wightii, possesses a variety of pharmacological activities. However, the effects of GS on psoriasis and the underlying mechanism have not been elucidated. In this study, we evaluated the therapeutic effect of GS on psoriasis using an imiquimod-induced psoriasis mouse model and investigated the effect of GS on human keratinocytes and the underlying mechanism. We found that GS effectively alleviated psoriasis-like skin lesions in imiquimod-induced psoriasis model mice and that GS suppressed the proliferation, migration, and production of proinflammatory cytokines, chemokines and antimicrobial peptides in keratinocytes. Transcriptome analysis by RNA-seq revealed that the differentially expressed genes (DEGs) induced by GS in keratinocytes were intricately linked to the pathogenesis of psoriasis. Furthermore, STAT3, a key player in the development and pathogenesis of psoriasis, was identified as a critical downstream mediator of GS in keratinocytes. Mechanistically, GS upregulated the expression of miR-17-5p, which directly binds to the 3'-untranslated regions (3'UTRs) of JAK1 and STAT3, leading to the downregulation of JAK1 and STAT3 expression. Collectively, these findings suggest that GS may serve as an effective natural compound for the treatment of psoriasis.

MiR-378 exaggerates angiogenesis and bone erosion in collagen-induced arthritis mice by regulating endoplasmic reticulum stress

Rheumatoid arthritis (RA) is a chronic autoimmune disorder marked by pain, inflammation, and discomfort in the synovial joints. It is critical to understand the pathological mechanisms of RA progression. MicroRNA-378 (miR-378) is highly expressed in the synovium of RA patients and positively correlated with disease severity, but its function and underlying mechanisms remain poorly understood. In this study, miR-378 transgenic (miR-378high) mice were used to construct the collagen-induced arthritis (CIA) model for exploring the role of miR-378 in RA development. miR-378high CIA mice showed accelerated RA development, as evidenced by exaggerated joint swelling and bone structural deformities. More severe endoplasmic reticulum (ER) stress and the consequent angiogenesis and osteoclastogenesis were also activated in the synovial tissue and calcaneus, respectively, in the miR-378high group, suggesting that ER plays a significant role in miR-378-mediated RA pathogenesis. Upon in vitro RA induction, fibroblast-like synoviocytes (FLSs) isolated from miR-378high mice showed a higher expression level of ER stress markers. The conditioned medium (CM) from RA-FLSs of miR-378high mice stimulated more intensive angiogenesis and osteoclastogenesis. The ER stress-related protein Crebrf was identified as a downstream target of miR-378. Crebrf knockdown diminished the promoting effect of miR-378 on ER stress, as well as its downstream angiogenesis and osteoclastogenesis activities. Tail vein injection of anti-miR-378 lentivirus in an established RA mouse model was shown to ameliorate RA progression. In conclusion, miR-378 amplified RA development by promoting ER stress and downstream angiogenesis and osteoclastogenesis, thus indicating that miR-378 may be a potential therapeutic target for RA treatment.

Unraveling the impact of miRNAs on gouty arthritis: diagnostic significance and therapeutic opportunities

Gouty arthritis is a prevalent inflammatory illness. Gout attacks begin when there is an imbalance in the body's uric acid metabolism, which leads to urate buildup and the development of the ailment. A family of conserved, short non-coding RNAs known as microRNAs (miRNAs) can regulate post-transcriptional protein synthesis by attaching to the 3' untranslated region (UTR) of messenger RNA (mRNA). An increasing amount of research is pointing to miRNAs as potential players in several inflammatory diseases, including gouty arthritis. miRNAs may influence the progression of the disease by regulating immune function and inflammatory responses. This review mainly focused on miRNAs and how they contribute to gouty arthritis. It also looked at how miRNAs could be used as diagnostic, prognostic, and potential therapeutic targets.

The role of non-coding RNAs in fibroblast-like synoviocytes in rheumatoid arthritis

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease characterized by synovial hyperplasia, and fibroblast-like synoviocytes (FLSs) constitute the majority of cells in the synovial tissue, playing a crucial role in the onset of RA. Dysregulation of FLSs function is a critical strategy in treating joint damage associated with RA. Non-coding RNAs, a class of RNA molecules that do not encode proteins, participate in the development of various diseases. This article aims to review the progress in the study of long non-coding RNAs, microRNAs, and circular RNAs in FLSs. Non-coding RNAs are involved in the pathogenesis of RA, directly or indirectly regulating FLSs' proliferation, migration, invasion, apoptosis, and inflammatory responses. Furthermore, non-coding RNAs also influence DNA methylation and osteogenic differentiation in FLSs. Therefore, non-coding RNAs hold promise as biomarkers for diagnosing RA. Targeting non-coding RNAs in FLSs locally represents a potential strategy for future therapies in RA.

JAK Inhibitors in Rheumatoid Arthritis: Immunomodulatory Properties and Clinical Efficacy

Rheumatoid arthritis (RA) is a highly prevalent autoimmune disorder. The pathogenesis of the disease is complex and involves various cellular populations, including fibroblast-like synoviocytes, macrophages, and T cells, among others. Identification of signalling pathways and molecules that actively contribute to the development of the disease is crucial to understanding the mechanisms involved in the chronic inflammatory environment present in affected joints. Recent studies have demonstrated that the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway regulates the behaviour of immune cells and contributes to the progression of RA. Several JAK inhibitors, such as tofacitinib, baricitinib, upadacitinib, and filgocitinib, have been developed, and their efficacy and safety in patients with RA have been comprehensively investigated in a number of clinical trials. Consequently, JAK inhibitors have been approved and registered as a treatment for patients with RA. In this review, we discuss the involvement of JAK/STAT signalling in the pathogenesis of RA and summarise the potential beneficial effects of JAK inhibitors in cells implicated in the pathogenesis of the disease. Moreover, we present the most important phase 3 clinical trials that evaluated the use of these agents in patients.

Cell-Based Therapy and Genome Editing as Emerging Therapeutic Approaches to Treat Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joints. Although much remains unknown about the pathogenesis of RA, there is evidence that impaired immune tolerance and the development of RA are related. And it is precisely the restoration of immune tolerance at the site of the inflammation that is the ultimate goal of the treatment of RA. Over the past few decades, significant progress has been made in the treatment of RA, with higher rates of disease remission and improved long-term outcomes. Unfortunately, despite these successes, the proportion of patients with persistent, difficult-to-treat disease remains high, and the task of improving our understanding of the basic mechanisms of disease development and developing new ways to treat RA remains relevant. This review focuses on describing new treatments for RA, including cell therapies and gene editing technologies that have shown potential in preclinical and early clinical trials. In addition, we discuss the opportunities and limitations associated with the use of these new approaches in the treatment of RA.

Unveiling Novel Drug Targets and Emerging Therapies for Rheumatoid Arthritis: A Comprehensive Review

Rheumatoid arthritis (RA) is a chronic debilitating autoimmune disease, that causes joint damage, deformities, and decreased functionality. In addition, RA can also impact organs like the skin, lungs, eyes, and blood vessels. This autoimmune condition arises when the immune system erroneously targets the joint synovial membrane, resulting in synovitis, pannus formation, and cartilage damage. RA treatment is often holistic, integrating medication, physical therapy, and lifestyle modifications. Its main objective is to achieve remission or low disease activity by utilizing a "treat-to-target" approach that optimizes drug usage and dose adjustments based on clinical response and disease activity markers. The primary RA treatment uses disease-modifying antirheumatic drugs (DMARDs) that help to interrupt the inflammatory process. When there is an inadequate response, a combination of biologicals and DMARDs is recommended. Biological therapies target inflammatory pathways and have shown promising results in managing RA symptoms. Close monitoring for adverse effects and disease progression is critical to ensure optimal treatment outcomes. A deeper understanding of the pathways and mechanisms will allow new treatment strategies that minimize adverse effects and maintain quality of life. This review discusses the potential targets that can be used for designing and implementing precision medicine in RA treatment, spotlighting the latest breakthroughs in biologics, JAK inhibitors, IL-6 receptor antagonists, TNF blockers, and disease-modifying noncoding RNAs.

Changes in Circulating MicroRNA Levels as Potential Indicators of Training Adaptation in Professional Volleyball Players

The increasing demand placed on professional athletes to enhance their fitness and performance has prompted the search for new, more sensitive biomarkers of physiological ability. One such potential biomarker includes microRNA (miRNA) small regulatory RNA sequences. The study investigated the levels of the selected circulating miRNAs before and after a 10-week training cycle in 12 professional female volleyball players, as well as their association with cortisol, creatine kinase (CK), and interleukin 6 (IL-6), using the qPCR technique. Significant decreases in the miR-22 (0.40 ± 0.1 vs. 0.28 ± 0.12, p = 0.009), miR-17 (0.35 ± 0.13 vs. 0.23 ± 0.08; p = 0.039), miR-24 (0.09 ± 0.04 vs. 0.05 ± 0.02; p = 0.001), and miR-26a (0.11 ± 0.06 vs. 0.06 ± 0.04; p = 0.003) levels were observed after training, alongside reduced levels of cortisol and IL-6. The correlation analysis revealed associations between the miRNAs' relative quantity and the CK concentrations, highlighting their potential role in the muscle repair processes. The linear regression analysis indicated that miR-24 and miR-26a had the greatest impact on the CK levels. The study provides insights into the dynamic changes in the miRNA levels during training, suggesting their potential as biomarkers for monitoring the adaptive responses to exercise. Overall, the findings contribute to a better understanding of the physiological effects of exercise and the potential use of miRNAs, especially miR-24 and miR-26a, as biomarkers in sports science and medicine.

Microarray analysis of microrna expression in peripheral blood mononuclear cells of patients with polymyositis and dermatomyositis

Background and Objectives

MicroRNAs (miRNAs) represent a new class of biomarkers in the context of connective tissue disorders. The miRNA expression profiles in peripheral blood mononuclear cells (PBMCs) of patients with polymyositis (PM) and dermatomyositis (DM) have not been fully elucidated. The objective is to investigate miRNAs expression profile in PBMCs of patients with PM/DM.

Methods

Microarray technology was used to identify differentially expressed miRNAs in PBMCs obtained from 6 untreated PM/DM patients and 3 healthy controls (HCs). TaqMan-based stem-loop real-time PCR detection was used for validation in a cohort of 34 PM/DM patients and 20 HCs.

Results

Microarray analysis revealed 38 differentially expressed miRNAs (24 up-regulated and 14 down-regulated) in PM/DM patients compared to HCs. Four miRNAs (miR-320a, miR-335-3p, miR-34a-5p and miR-454-3p) were chosen for real-time PCR validation. The expression of miR-34a-5p was significantly upregulated in PM/DM group (P < 0.05). In subgroup analysis, miR-34a-5p was significantly upregulated in interstitial lung disease (ILD) group and DM group (P < 0.001). The level of SIRT1, a validated target of miR-34a, was significantly lower in PBMCs of PM/DM patients compared with HCs.

Conclusions

MiR-34a-5p may potentially participate in the pathogenesis of PM/DM through SIRT1, and may serve as a potential new biomarker for PM/DM-ILD.

Natural compound library screening to identify berberine as a treatment for rheumatoid arthritis

OBJECTIVE

Fibroblast-like synoviocytes (FLS) play a critical role on the exacerbation and deterioration of rheumatoid arthritis (RA). Aberrant activation of FLS pyroptosis signaling is responsible for the hyperplasia of synovium and destruction of cartilage of RA. This study investigated the screened traditional Chinese medicine berberine (BBR), an active alkaloid extracted from the Coptis chinensis plant, that regulates the pyroptosis of FLS and secretion of inflammatory factors in rheumatoid arthritis.

METHODS

First, BBR was screened using a high-throughput drug screening strategy, and its inhibitory effect on RA-FLS was verified by in vivo and in vitro experiments. Second, BBR was intraperitoneally administrated into the collagen-induced arthritis rat model, and the clinical scores, arthritis index, and joint HE staining were evaluated. Third, synovial tissues of CIA mice were collected, and the expression of NLRP3, cleaved-caspase-1, GSDMD-N, Mst1, and YAP was detected by Western blot.

RESULTS

The administration of BBR dramatically alleviated the severity of collagen-induced arthritis rat model with a decreased clinical score and inflammation reduction. In addition, BBR intervention significantly attenuates several pro-inflammatory cytokines (interleukin-1β, interleukin-6, interleukin-17, and interleukin-18). Moreover, BBR can reduce the pyroptosis response (caspase-1, NLR family pyrin domain containing 3, and gasdermin D) of the RA-FLS in vitro, activating the Hippo signaling pathway (Mammalian sterile 20-like kinase 1, yes-associated protein, and transcriptional enhanced associate domains) so as to inhibit the pro-inflammatory effect of RA-FLS.

CONCLUSION

These results support the role of BBR in RA and may have therapeutic implications by directly repressing the activation, migration of RA-FLS, which contributing to the attenuation of the progress of CIA. Therefore, targeting PU.1 might be a potential therapeutic approach for RA. Besides, BBR inhibited RA-FLS pyroptosis by downregulating of NLRP3 inflammasomes (NLRP3, caspase-1) and eased the pro-inflammatory activities via activating the Hippo signaling pathway, thereby improving the symptom of CIA.

Nitazoxanide reduces inflammation and bone erosion in mice with collagen-induced arthritis via inhibiting the JAK2/STAT3 and NF-κB pathways in fibroblast-like synoviocytes

Our recent study showed that Nitazoxanide (NTZ), an FDA-approved anti-parasitic drug, prevents ovariectomy-induced bone loss by inhibiting osteoclast activity. However, there have been no investigations to determine whether NTZ has preventive potential in other bone resorbing diseases, especially rheumatoid arthritis (RA). In this study, the primary RA fibroblast-like synoviocytes (RA-FLS) and collagen-induced arthritis (CIA) murine model were used to evaluate the effect of NTZ. The results showed that NTZ potently inhibited proliferation, migration and invasion capacity of RA-FLS in a dose dependent manner by restraining cell entry into S phases, without induction of cell apoptosis. NTZ obviously reduced spontaneous mRNA expression of IL-1β, IL-6 and RANKL, as well as TNF-α-induced transcription of the IL-1β, IL-6, and MMP9 genes. In terms of molecular mechanism, NTZ significantly inhibited the basal or TNF-α-induced activation of JAK2/STAT3 (T705) and NF-κB pathway, but not MAPK and STAT3 (S727) phosphorylation. Moreover, NTZ ameliorated synovial inflammation and bone erosion in CIA mice through reducing the production of inflammatory mediators and osteoclast formation, respectively. Collectively, our findings indicate that NTZ exhibits anti-inflammatory and anti-erosive effects both ex vivo and in vivo, which provides promising evidence for the therapeutic application of NTZ as a novel therapeutic agent for RA.

Mechanistic evaluation of antiarthritic and anti-inflammatory effect of campesterol ester derivatives in complete Freund's adjuvant-induced arthritic rats

Background: Current therapies for RA have limitations and side effects, leading to a growing need for safer treatment options. Natural compounds from plants are gaining attention for their therapeutic benefits and fewer side effects. One such compound is the campesterol derivative, a steroid derivative occurring in plants. Studies have shown that this derivative has anti-inflammatory properties and can impact the expression of pro-inflammatory factors. The primary objective of this study was to explore and assess the potential therapeutic effects of Campesterol Ester Derivatives (CED) utilizing a rat model of arthritis induced by Complete Freund's Adjuvant (CFA). Method: The rats were divided into specific experimental groups and treated with either CED or piroxicam (as a positive control) for a duration of 28 days. We determined the effects of CED on various parameters including paw edema, thermal hyperalgesia, and mechanical allodynia at different time points. Furthermore, serum levels of inflammatory cytokines, oxidative stress markers and histological analyses were performed. Additionally, mRNA expression levels of inflammatory markers, both pro-inflammatory (such as TNF-α, NF-κB, IL-6, COX-1, COX-2, and IL-4) and anti-inflammatory were analyzed. Results: In the arthritic rat model, CED exhibited significant anti-inflammatory effects and resulted in a notable reduction in paw edema levels compared to the control group. Histopathological examination of the treated rats' paws confirmed a decrease in inflammation and tissue damage, including reduced pannus formation and bone erosion. Importantly, there were no observable signs of damage to the liver and kidneys following CED treatment, indicating its safety profile and potential for organ protection. At the molecular level, CED treatment downregulated mRNA expression levels of pro-inflammatory markers, indicating its ability to suppress inflammation. Conversely, certain anti-inflammatory markers were upregulated following CED treatment, suggesting a positive influence on the immune response. The positive effects of CED were not limited to joint inflammation; it also showed systemic benefits by positively influencing hematological and biochemical parameters. Conclusion: CED demonstrated promising therapeutic potential as an anti-inflammatory intervention for arthritis in the experimental rat model. Its ability to reduce inflammation, protect tissues, and improve organ function indicates its multifaceted benefits.

Forsythiaside A exhibits anti-migration and anti-inflammation effects in rheumatoid arthritis in vitro model

BACKGROUND

Rheumatoid arthritis (RA) is a kind of systemic autoimmune disease, and the joint inflammation and cartilage destruction are the major features. Some traditional Chinese medicine have been discovered to exhibit regulatory roles in the treatment of RA. Forsythiaside A (FA) as an active ingredient isolated from forsythia suspensa has been discovered to participate into the regulation of some diseases through improving inflammation. However, the regulatory effects of FA on the progression of RA keep indistinct.

METHODS

IL-1β treatment (10 ng/mL) in MH7A cells was built to mimic RA in vitro (cell) model. The cell viability was examined through CCK-8 assay. The cell proliferation was detected through Edu assay. The levels of TNF-α, IL-6, and IL-8 were evaluated through ELISA. The protein expressions were measured through western blot. The cell apoptosis was assessed through flow cytometry. The cell migration and invasion abilities were tested through Transwell assay.

RESULTS

In this study, it was revealed that the cell proliferation was strengthened after IL-1β treatment (p < .001), but this effect was reversed after FA treatment in a dose-increasing manner (p < .05). Furthermore, FA suppressed inflammation in IL-1β-triggered MH7A cells through attenuating the levels of TNF-α, IL-6, and IL-8 (p < .05). The cell apoptosis was lessened after IL-1β treatment (p < .001), but this effect was rescued after FA treatment (p < .05). Besides, the cell migration and invasion abilities were both increased after IL-1β treatment (p < .001), but these changes were offset after FA treatment (p < .05). Eventually, FA retarded the JAK/STAT pathway through reducing p-JAK/JAK and p-STAT/STAT levels (p < .01).

CONCLUSION

Our study manifested that FA exhibited anti-migration and anti-inflammation effects in RA in vitro model (IL-1β-triggered MH7A cells) through regulating the JAK/STAT pathway. This work hinted that FA can be an effective drug for RA treatment.

miR-212/132 attenuates OVA-induced airway inflammation by inhibiting mast cells activation through MRGPRX2 and ASAP1

Allergic asthma is a chronic inflammatory disease of airways involving complex mechanisms, including MAS-related GPR family member X2 (MRGPRX2) and its orthologue MRGPRB2 on mast cells (MCs). Although miRNAs have been previously shown to related to allergic asthma, the role of miR-212/132 in this process has not been studied. In this study, the predicted pairing of miRNAs and MRGPRX2 (MRGPRB2) mRNAs was carried out by online databases and the function was verify using in vivo and in vitro experiments. Database prediction showed that miR-212/132 interact with MRGPRX2 and MRGPRB2. miR-212/132 mimics alleviated MRGPRB2 mRNA expression as well as pathology changes in lungs and AHR of mice with airway inflammation in vivo. The expression level of MRGPRB2 in the mice lungs after inhaled OVA was also decreased by miR-212/132 mimics. Meanwhile, miR-212/132 inhibited MCs degranulation and cytokines release triggered by C48/80 in vitro. Further, ASAP1 (ARF GTPase-Activating Protein 1) was selected from the junction related pathways using RNAseq and KEGG enrichment. ASAP1 mRNA level was upregulated in airway inflammation and MCs activation and decreased by miR-212/132 mimics. miR-212/132 attenuated OVA-induced airway inflammation by inhibiting MCs activation through MRGPRX2 and ASAP1.

Vetiver aerial parts and roots ameliorate rheumatoid arthritis in complete Freund's adjuvant rat model, a phytochemical profiling and mechanistic study

ETHNOPHARMACOLOGICAL RELEVANCE

Vetiver (Chrysopogon zizanioides) is indigenous to India where it is traditionally used to relief rheumatisms, lumbagos and sprains. Vetiver anti-inflammatory activity has not been previously investigated, and its specific interactions with body inflammation cascade remain largely unknown.

AIM OF THE STUDY

The present work was performed to validate the ethnobotanical use of the plant and compare the anti-inflammatory activities of the ethanolic extracts of the most traditionally used part (aerial part) to that of the root. Furthermore, we attempt to reveal the molecular mechanism of this anti-inflammatory activity in correlation to the chemical composition of C. zizanioides aerial (CA) and root parts (CR).

MATERIALS AND METHODS

Ultraperformance liquid chromatography coupled to high resolution mass spectrometry (UHPLC/HRMS) was used for comprehensive analysis of both CA and CR. The anti-inflammatory effect of both extracts was evaluated in complete Freund's adjuvant (CFA)-induced RA model in Wistar rats.

RESULTS

Phenolic metabolites were predominant in CA and 42 were identified for the first time, while only 13 were identified in CR. Meanwhile, triterpenes and sesquiterpenes were confined to the root extract. In CFA arthritis model, CA showed better anti-inflammatory activity than CR marked by an increase in serum level of IL-10 with simultaneous decrease in pro-inflammatory markers; IL-6, ACPA and TNF-α and was evident in histopathological examination. This anti-inflammatory effect was accompanied by down-regulation of JAK2/STAT3/SOCs3, ERK1/ERK2, TRAF6/c-FOS/NFATC1, TRAF6/NF-κB/NFATC1 and RANKL pathways which were all upregulated after CFA injection. These pathways were modulated to larger extent by CA, except for ERK1/ERK2 which was downregulated more effectively by CR. This differential effect between CA and CR can be explained by the variability in their phytoconstituents profile.

CONCLUSION

In agreement with the ethnobotanical preference, CA extract was more effective than CR extract in reducing the symptoms of RA probably due to its enrichment with flavonoids, lignans, and flavolignans. Both CA and CR reduced the production of inflammatory cytokines through modulating various biological signaling pathways. These findings support the traditional use of vetiver leaves as a remedy for RA and suggest that the use of the whole plant may offer advantage by synergistically affecting more inflammatory pathways.

Potential significance of changes in serum levels of IL-17, TNF-α and DKK-1 in the progression of the rheumatoid arthritis

To detect the value of serum interleukin-17 (IL-17), tumour necrosis factor-α (TNF-α), and Dickkopf-1 (DKK-1) in rheumatoid arthritis (RA) at different disease stages. 141 RA patients were randomly obtained and diagnosed in a large tertiary first-class hospital in Jiangxi Province from November 2021 to January 2022. RA was divided into 38 low activity and remission phase (low remission patients), 72 moderate activity patients, 41 high activity patients, according to the disease activity score 28 (DAS28) of RA and 70 healthy controls. IL-17 and TNF-α in serum detected by flow cytometry; DKK-1by ELISA; rheumatoid factor (RF) and C-reactive protein (CRP) by rate scattering turbidimetry; erythrocyte sedimentation rate (ESR) by Widmanstat method; anti-cyclic citrullinated polypeptide antibody (Anti-CCP) by chemiluminescence. The changes among the groups were statistically analysed and evaluated their diagnostic value. ①Anti-CCP, CRP, and ESR levels in the moderate-to-high activity group were higher than controls, while IL-17, TNF-α, and DKK-1levels higher than low remission group, moderate activity group and controls (p < 0.05). ②IL-17, TNF-α and DKK-1 were positively correlated with RA disease activity, with the correlations of IL-17, TNF-α and DKK-1 all over 0.5 (p < 0.05). ③The ROC curve showed that among all indices the AUC of DKK-1 was the largest, 0. 922, and has the highest sensitivity and negative predictive value for RA, 0.965 and 0.953, respectively. The specificity and positive predictive value of TNF-α is highest, 0.918 and 0.921, respectively, combined them had the highest predictive value in moderate-to-high activity RA, with AUC of 0.968, and had the highest sensitivity of 0.965. The IL-17, TNF-α and DKK-1 levels were elevated in RA and positively correlated with disease activity, involved in the Wnt signalling pathway of inflammatory and joint destructive effects, combining them to monitor the RA disease process and biologically treat the cytokines in the pathogenesis of RA were valuable.

Gut microbiota in pre-clinical rheumatoid arthritis: From pathogenesis to preventing progression

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by progressive polyarthritis that leads to cartilage and bone damage. Pre-clinical RA is a prolonged state before clinical arthritis and RA develop, in which autoantibodies (antibodies against citrullinated proteins, rheumatoid factors) can be present due to the breakdown of immunologic self-tolerance. As early treatment initiation before the onset of polyarthritis may achieve sustained remission, optimize clinical outcomes, and even prevent RA progression, the pre-clinical RA stage is showing the prospect to be the window of opportunity for RA treatment. Growing evidence has shown the role of the gut microbiota in inducing systemic inflammation and polyarthritis via multiple mechanisms, which may involve molecular mimicry, impaired intestinal barrier function, gut microbiota-derived metabolites mediated immune regulation, modulation of the gut microbiota's effect on immune cells, intestinal epithelial cells autophagy, and the interaction between the microbiome and human leukocyte antigen alleles as well as microRNAs. Since gut microbiota alterations in pre-clinical RA have been reported, potential therapies for modifying the gut microbiota in pre-clinical RA, including natural products, antibiotic therapy, fecal microbiota transplantation, probiotics, microRNAs therapy, vitamin D supplementation, autophagy inducer-based treatment, prebiotics, and diet, holds great promise for the successful treatment and even prevention of RA via altering ongoing inflammation. In this review, we summarized current studies that include pathogenesis of gut microbiota in RA progression and promising therapeutic strategies to provide novel ideas for the management of pre-clinical RA and possibly preventing arthritis progression.

PR-957 retards rheumatoid arthritis progression and inflammation by inhibiting LMP7-mediated CD4+ T cell imbalance

OBJECTIVE

Low molecular mass polypeptide 7 (LMP7) is an immunoproteasome subunit that regulates T cell amplification, differentiation, and inflammation and is involved in rheumatoid arthritis (RA) progression. This study intended to apply PR-957 (an anti-LMP7 agent) for RA treatment in vitro and in vivo and evaluate its interaction with LMP7-mediated CD4+ T cell imbalance.

METHODS

Peripheral blood mononuclear cells (PBMCs) were obtained from 30 RA patients and 30 healthy controls. RA fibroblast-like synoviocytes (RA-FLSs) and CD4+ T cells were isolated from RA patients and then cocultured with PR-957 and/or LMP7 overexpression adenovirus (Ad-LMP7). Collagen-induced arthritis (CIA) mice were constructed and then treated with PR-957 and/or Ad-LMP7.

RESULTS

LMP7 was higher in RA patients (versus healthy controls) and positively correlated with T helper (Th)1 cells, the Th1/Th2 ratio, Th17 cells, and the Th17/Treg ratio but not with Th2 or T regulatory (Treg) cells. PR-957 reduced Th1 and Th17 cells but increased Th2 and Treg cells in RA-CD4+ T cells, and this effect was partially reversed by Ad-LMP7 transfection. Interestingly, when cocultured with RA-CD4+ T cells, PR-957 increased RA-FLS apoptosis and decreased its invasive ability, viability, and inflammation, as suggested by IL-6, CCL2, MMP1, and MMP3; however, these phenomena were weakened in RA-FLSs without RA-CD4+ T cell coculture. In addition, Ad-LMP7 transfection attenuated the above effects of PR-957. In CIA mice, PR-957 decreased the arthritis score, synovial hyperproliferation and articular injury, inflammation in the synovium and serum, and the imbalance of Th1/Th2 and Th17/Treg in the spleen, and these effects were attenuated by Ad-LMP7.

CONCLUSION

PR-957 ameliorates RA progression and inflammation by repressing LMP7-mediated CD4+ T cell imbalance.

Bone marrow-derived exosomes promote inflammation and osteoclast differentiation in high-turnover renal osteodystrophy

Introduction: Renal osteodystrophy (ROD) is a type of bone metabolic disorder in patients with chronic kidney disease (CKD). Inflammation is associated with bone loss in ROD. However, its precise mechanism has not yet been elucidated. The present study was conducted to investigate whether exosomes (Exos) in bone marrow (BM) are involved in the pathogenesis of high-turnover ROD.Methods: Bone mass, osteoclast number, and pro-inflammatory cytokines levels of BM supernatant were detected in adenine-induced ROD rats. The effect of Exos derived from BM (BM-Exos) of ROD (ROD-Exos) on inflammatory genes and osteoclast differentiation of BM-derived macrophages (BMMs) were further examined. Then, exosomal miRNA sequencing was performed and an miRNA-mRNA-pathway network was constructed.Results: we found increased osteoclasts and decreased bone mass in ROD rats, as well as inflammatory activation in the BM niche. Furthermore, BMMs from ROD rats displayed overproduction of proinflammatory cytokines and increased osteoclast differentiation, accompanied by nuclear factor κB (NF-κB) signaling activation. Mechanistically, we found that ROD-Exos activates NF-κB signaling to promote the release of proinflammatory cytokines and increase osteoclast differentiation of BMMs. Meanwhile, a total of 24 differentially expressed miRNAs were identified between BM-Exos from ROD and normal control (NC). The miRNA-mRNA-pathway network suggests that rno-miR-9a-5p, rno-miR-133a-3p, rno-miR-30c-5p, rno-miR-206-3p, and rno-miR-17-5p might play pivotal roles in inflammation and osteoclast differentiation. Additionally, we validated that the expression of miR-9a-5p is upregulated in ROD-Exos.Conclusion: The BM niche of ROD alters the miRNA cargo of BM-Exos to promote inflammation and osteoclast differentiation of BMMs, at least partially contributing to the pathogenesis of high-turnover ROD.

The mechanism of LZ-8-mediated immune response in the mouse model of Parkinson's disease

Parkinson's disease (PD) is associated with microscopic changes in the brain, particularly substantia nigra (SN). Ganoderma lucidum immunoregulatory protein (rLZ-8) is might confer protective effects against PD. We developed a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced murine model of PD and determined the effects of rLZ-8 on molecular and cellular components of SN and whole brain tissue. The levels of SOD, GSH-Px, p-JAK2 and p-STAT3 in the brain tissue and SN were downregulated, while IL-6, IL-1β, and TNF-α and MDA were upregulated. These effects were significantly reversed upon treatment rLZ-8. In summary, oxidative stress and inflammatory response in PD can be alleviated using rLZ-8.

Schisandrin treatment suppresses the proliferation, migration, invasion, and inflammatory responses of fibroblast-like synoviocytes from rheumatoid arthritis patients and attenuates synovial inflammation and joint destruction in CIA mice

BACKGROUND

Rheumatoid arthritis (RA) is a systemic autoimmune disease causing joint dysfunction. As disease-modifying anti-rheumatic drugs (DMARDs) have poor efficacy in 20% to 25% of RA patients, additional novel RA medications are urgently needed. Schisandrin (SCH) has multiple therapeutic effects. However, whether SCH is effective against RA remains unknown.

PURPOSE

To investigate how SCH affects the abnormal behaviours of RA fibroblast-like synoviocytes (FLSs) and further elucidate the underlying mechanism of SCH in RA FLSs and collagen-induced arthritis (CIA) mice.

METHODS

Cell Counting Kit-8 (CCK8) assays were used to characterize cell viability. EdU assays were performed to assess cell proliferation. Annexin V-APC/PI assays were used to determine apoptosis. Transwell chamber assays were used to measure cell migration and invasion in vitro. RT-qPCR was used to assess proinflammatory cytokine and MMP mRNA expression. Western blotting was used to detect protein expression. RNA sequencing was performed to explore the potential downstream targets of SCH. CIA model mice were used to assess the treatment efficacy of SCH in vivo.

RESULTS

Treatments with SCH (50, 100, and 200 μΜ) inhibited RA FLSs proliferation, migration, invasion, and TNF-α-induced IL-6, IL-8, and CCL2 expression in a dose-dependent manner but did not affect RA FLSs viability or apoptosis. RNA sequencing and Reactome enrichment analysis indicated that SREBF1 might be the downstream target in SCH treatment. Furthermore, knockdown of SREBF1 exerted effects similar to those of SCH in inhibiting RA FLSs proliferation, migration, invasion, and TNF-α-induced expression of IL-6, IL-8, and CCL2. Both SCH treatment and SREBF1 knockdown decreased activation of the PI3K/AKT and NF-κB signalling pathways. Moreover, SCH ameliorated joint inflammation and cartilage and bone destruction in CIA model mice.

CONCLUSION

SCH controls the pathogenic behaviours of RA FLSs by targeting SREBF1-mediated activation of the PI3K/AKT and NF-κB signalling pathways. Our data suggest that SCH inhibits FLS-mediated synovial inflammation and joint damage and that SCH might have therapeutic potential for RA.

Multiplex Analysis of Cerebrospinal Fluid and Serum Exosomes MicroRNAs of Untreated Relapsing Remitting Multiple Sclerosis (RRMS) and Proposing Noninvasive Diagnostic Biomarkers

Exosomal microRNAs (miRNAs) are emerging diagnostic biomarkers for neurodegenerative diseases. In this study, we aimed to detect relapsing-remitting multiple sclerosis (RRMS)-specific miRNAs in cerebrospinal fluid (CSF) and serum exosomes with diagnostic potential. One ml of CSF and serum sample were collected from each of the 30 untreated RRMS patients and healthy controls (HCs). A panel of 18 miRNAs affecting inflammatory responses was applied, and qRT-PCR was conducted to detect differentially expressed exosomal miRNAs in CSF and serum of RRMS patients. We identified that 17 out of 18 miRNAs displayed different patterns in RRMS patients compared to HCs. Let-7 g-5p, miR-18a-5p, miR-145-5p, and miR-374a-5p with dual pro-inflammatory and anti-inflammatory actions and miR-150-5p and miR-342-3p with anti-inflammatory action were significantly upregulated in both CSF and serum-derived exosomes of RRMS patients compared to corresponding HCs. Additionally, anti-inflammatory miR-132-5p and pro-inflammatory miR-320a-5p were significantly downregulated in both CSF and serum-derived exosomes of RRMS patients compared to HCs. Ten of 18 miRNAs were differentially expressed in CSF and serum exosomes of the patients. Furthermore, miR-15a-5p, miR-19b-3p, and miR-432-5p were upregulated, and miR-17-5p was downregulated only in CSF exosomes. Interestingly, U6 housekeeping gene was differentially expressed in CSF and serum exosomes, in both RRMS and HCs. As the first report describing CSF exosomal miRNAs expression profile compared to that of serum exosomes in untreated RRMS patients, we showed that CSF and serum exosomes are not identical in terms of biological compounds and display different patterns in miRNAs and U6 expression.

Role of miRNAs in Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease characterized by autoimmunity, synovial inflammation and joint destruction. Pannus formation in the synovial cavity can cause irreversible damage to the joint and cartilage and eventually permanent disability. Current conventional treatments for RA have limitations regarding efficacy, safety and cost. microRNA (miRNA) is a type of non-coding RNA (ncRNA) that regulates gene expression at the post-transcriptional level. The dysregulation of miRNA has been observed in RA patients and implicated in the pathogenesis of RA. miRNAs have emerged as potential biomarkers or therapeutic agents. In this review, we explore the role of miRNAs in various aspects of RA pathophysiology, including immune cell imbalance, the proliferation and invasion of fibroblast-like synovial (FLS) cell, the dysregulation of inflammatory signaling and disturbance in angiogenesis. We delve into the regulatory effects of miRNAs on Treg/Th17 and M1/M2 polarization, the activation of the NF-κB/NLRP3 signaling pathway, neovascular formation, energy metabolism induced by FLS-cell-induced energy metabolism, apoptosis, osteogenesis and mobility. These findings shed light on the potential applications of miRNAs as diagnostic or therapeutic biomarkers for RA management. Furthermore, there are some strategies to regulate miRNA expression levels by utilizing miRNA mimics or exosomes and to hinder miRNA activity via competitive endogenous RNA (ceRNA) network-based antagonists. We conclude that miRNAs offer a promising avenue for RA therapy with unlimited potential.

Effects of miR-33 Deficiency on Metabolic and Cardiovascular Diseases: Implications for Therapeutic Intervention

MicroRNAs (miRNAs) are small noncoding RNAs that post-transcriptionally inhibit gene expression. These small molecules are involved in several biological conditions such as inflammation, cell growth and proliferation, and regulation of energy metabolism. In the context of metabolic and cardiovascular diseases, miR-33 is of particular interest as it has been implicated in the regulation of lipid and glucose metabolism. This miRNA is located in introns harboured in the genes encoding sterol regulatory element-binding protein (SREBP)-1 and SREBP-2, which are key transcription factors involved in lipid biosynthesis and cholesterol efflux. This review outlines the role of miR-33 in a range of metabolic and cardiovascular pathologies, such as dyslipidaemia, nonalcoholic fatty liver disease (NAFLD), obesity, diabetes, atherosclerosis, and abdominal aortic aneurysm (AAA), and it provides discussion about the effectiveness of miR-33 deficiency as a possible therapeutic strategy to prevent the development of these diseases.

Can pyroptosis be a new target in rheumatoid arthritis treatment?

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease of undefined etiology, with persistent synovial inflammation and destruction of articular cartilage and bone. Current clinical drugs for RA mainly include non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, disease modifying anti-rheumatic drugs (DMARDs) and so on, which can relieve patients' joint symptoms. If we want to have a complete cure for RA, there are still some limitations of these drugs. Therefore, we need to explore new mechanisms of RA to prevent and treat RA radically. Pyroptosis is a newly discovered programmed cell death (PCD) in recent years, which is characterized by the appearance of holes in cell membranes, cell swelling and rupture, and the release of intracellular pro-inflammatory factors into the extracellular space, resulting in a strong inflammatory response. The nature of pyroptosis is pro-inflammatory, and whether it is participating in the development of RA has attracted a wide interest among scholars. This review describes the discovery and mechanism of pyroptosis, the main therapeutic strategies for RA, and the role of pyroptosis in the mechanism of RA development. From the perspective of pyroptosis, the study of new mechanisms of RA may provide a potential target for the treatment of RA and the development of new drugs in the clinics.

Synovial monocytes contribute to chronic inflammation in childhood-onset arthritis via IL-6/STAT signalling and cell-cell interactions

Introduction

Monocytes are key effector cells in inflammatory processes. We and others have previously shown that synovial monocytes in childhood-onset arthritis are activated. However, very little is known about how they contribute to disease and attain their pathological features. Therefore, we set out to investigate the functional alterations of synovial monocytes in childhood-onset arthritis, how they acquire this phenotype, and whether these mechanisms could be used to tailorize treatment.

Methods

The function of synovial monocytes was analysed by assays believed to reflect key pathological events, such as T-cell activation-, efferocytosis- and cytokine production assays using flow cytometry in untreated oligoarticular juvenile idiopathic arthritis (oJIA) patients (n=33). The effect of synovial fluid on healthy monocytes was investigated through mass spectrometry and functional assays. To characterize pathways induced by synovial fluid, we utilized broad-spectrum phosphorylation assays and flow cytometry, as well as inhibitors to block specific pathways. Additional effects on monocytes were studied through co-cultures with fibroblast-like synoviocytes or migration in transwell systems.

Results

Synovial monocytes display functional alterations with inflammatory and regulatory features, e.g., increased ability to induce T-cell activation, resistance to cytokine production following activation with LPS and increased efferocytosis. In vitro, synovial fluid from patients induced the regulatory features in healthy monocytes, such as resistance to cytokine production and increased efferocytosis. IL-6/JAK/STAT signalling was identified as the main pathway induced by synovial fluid, which also was responsible for a majority of the induced features. The magnitude of synovial IL-6 driven activation in monocytes was reflected in circulating cytokine levels, reflecting two groups of low vs. high local and systemic inflammation. Remaining features, such as an increased ability to induce T-cell activation and markers of antigen presentation, could be induced by cell-cell interactions, specifically via co-culture with fibroblast-like synoviocytes.

Conclusions

Synovial monocytes in childhood-onset arthritis are functionally affected and contribute to chronic inflammation, e.g., via promoting adaptive immune responses. These data support a role of monocytes in the pathogenesis of oJIA and highlight a group of patients more likely to benefit from targeting the IL-6/JAK/STAT axis to restore synovial homeostasis.

Dihydromyricetin Inhibits M1 Macrophage Polarization in Atherosclerosis by Modulating miR-9-Mediated SIRT1/NF-κB Signaling Pathway

Dihydromyricetin (DMY), a natural flavonoid compound extracted from the stems and leaves of Ampelopsis grossedentata, has been found as a potential therapeutic chemical for treating atherosclerosis. This study explores the underlying mechanism of DMY repressing M1 macrophage polarization in atherosclerosis. We showed that DMY treatment markedly decreased M1 macrophage markers (e.g., Tnf-α and IL-1β) and p65-positive macrophage numbers in the vessel wall of Apoe-deficient (Apoe^-/-) mice. Overexpression of miR-9 or knockdown of SIRT1 in macrophages reversed the effect of DMY on M1 macrophage polarization. The data we presented in the study indicate that the miR-9-mediated SIRT1/NF-κB pathway plays a pivotal role in M1 macrophage polarization and is one of the molecular mechanisms underlying the anti-atherosclerosis effects of DMY. We provide new solid evidence that DMY may be explored as a potential therapeutic adjuvant for treating atherosclerosis.

Lyn attenuates sepsis-associated acute kidney injury by inhibition of phospho-STAT3 and apoptosis

Sepsis-associated acute kidney injury (SA-AKI) is a life-threatening condition associated with high mortality and morbidity. However, the underlying pathogenesis of SA-AKI is still unclear. Lyn belongs to Src family kinases (SFKs), which exert numerous biological functions including modulation in receptor-mediated intracellular signaling and intercellular communication. Previous studies demonstrated that Lyn gene deletion obviously aggravates LPS-induced lung inflammation, but the role and possible mechanism of Lyn in SA-AKI have not been reported yet. Here, we found that Lyn protected against renal tubular injury in cecal ligation and puncture (CLP) induced AKI mouse model by inhibition of signal transducer and activator of transcription 3 (STAT3) phosphorylation and cell apoptosis. Moreover, Lyn agonist MLR-1023 pretreatment improved renal function, inhibited STAT3 phosphorylation and decreased cell apoptosis. Thus, Lyn appears to play a crucial role in orchestrating STAT3-mediated inflammation and cell apoptosis in SA-AKI. Hence, Lyn kinase may be a promising therapeutic target for SA-AKI.

miRNAs insights into rheumatoid arthritis: Favorable and detrimental aspects of key performers

Rheumatoid arthritis (RA) is a severe autoimmune inflammation that mostly affects the joints. It's a multifactorial disease. Its clinical picture depends on genetic and epigenetic factors such as miRNAs. The miRNAs are small noncoding molecules that are able to negatively or positively modulate their target gene expression. In RA, miRNAs are linked to its pathogenesis. They disrupt immunity balance by controlling granulocytes, triggering the release of several proinflammatory cytokines such as interleukin-6 and tumor necrosis factor-α, finally leading to synovium hyperplasia and inflammation. Besides, they also may trigger activation of some pathways as nuclear factor kappa-β disrupts the balance between osteoclast and osteoblast activity, leading to increased bone destruction. Moreover, miRNAs are also applied with efficiency in RA diagnosis and prognosis. Besides the significant association between miRNAs and RA response to treatment, they are also applied as a choice for treatment based on their effects on the immune system and inflammatory cytokines. Hence, the review aims to present an updated overview of miRNAs, their biogenesis, implications in RA pathogenesis, and finally, the role of miRNAs in RA treatment.

Melanocortin therapies to resolve fibroblast-mediated diseases

Stromal cells have emerged as central drivers in multiple and diverse diseases, and consequently, as potential new cellular targets for the development of novel therapeutic strategies. In this review we revise the main roles of fibroblasts, not only as structural cells but also as players and regulators of immune responses. Important aspects like fibroblast heterogeneity, functional specialization and cellular plasticity are also discussed as well as the implications that these aspects may have in disease and in the design of novel therapeutics. An extensive revision of the actions of fibroblasts on different conditions uncovers the existence of numerous diseases in which this cell type plays a pathogenic role, either due to an exacerbation of their 'structural' side, or a dysregulation of their 'immune side'. In both cases, opportunities for the development of innovative therapeutic approaches exist. In this regard, here we revise the existing evidence pointing at the melanocortin pathway as a potential new strategy for the treatment and management of diseases mediated by aberrantly activated fibroblasts, including scleroderma or rheumatoid arthritis. This evidence derives from studies involving models of in vitro primary fibroblasts, in vivo models of disease as well as ongoing human clinical trials. Melanocortin drugs, which are pro-resolving mediators, have shown ability to reduce collagen deposition, activation of myofibroblasts, reduction of pro-inflammatory mediators and reduced scar formation. Here we also discuss existing challenges, both in approaching fibroblasts as therapeutic targets, and in the development of novel melanocortin drug candidates, that may help advance the field and deliver new medicines for the management of diseases with high medical needs.

Comprehensive overview of microRNA function in rheumatoid arthritis

MicroRNAs (miRNAs), a class of endogenous single-stranded short noncoding RNAs, have emerged as vital epigenetic regulators of both pathological and physiological processes in animals. They direct fundamental cellular pathways and processes by fine-tuning the expression of multiple genes at the posttranscriptional level. Growing evidence suggests that miRNAs are implicated in the onset and development of rheumatoid arthritis (RA). RA is a chronic inflammatory disease that mainly affects synovial joints. This common autoimmune disorder is characterized by a complex and multifaceted pathogenesis, and its morbidity, disability and mortality rates remain consistently high. More in-depth insights into the underlying mechanisms of RA are required to address unmet clinical needs and optimize treatment. Herein, we comprehensively review the deregulated miRNAs and impaired cellular functions in RA to shed light on several aspects of RA pathogenesis, with a focus on excessive inflammation, synovial hyperplasia and progressive joint damage. This review also provides promising targets for innovative therapies of RA. In addition, we discuss the regulatory roles and clinical potential of extracellular miRNAs in RA, highlighting their prospective applications as diagnostic and predictive biomarkers.

Epigenetic Regulations in Autoimmunity and Cancer: from Basic Science to Translational Medicine

Epigenetics, as a discipline that aims to explain the differential expression of phenotypes arising from the same gene sequence and the heritability of epigenetic expression, has received much attention in medicine. Epigenetic mechanisms are constantly being discovered, including DNA methylation, histone modifications, noncoding RNAs and m6A. The immune system mainly achieves an immune response through the differentiation and functional expression of immune cells, in which epigenetic modification will have an important impact. Because of immune infiltration in the tumor microenvironment, immunotherapy has become a research hotspot in tumor therapy. Epigenetics plays an important role in autoimmune diseases and cancers through immunology. An increasing number of drugs targeting epigenetic mechanisms, such as DNA methyltransferase inhibitors, histone deacetylase inhibitors, and drug combinations, are being evaluated in clinical trials for the treatment of various cancers (including leukemia and osteosarcoma) and autoimmune diseases (systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis). This review summarizes the progress of epigenetic regulation for cancers and autoimmune diseases to date, shedding light on potential therapeutic strategies.

Fibroblast heterogeneity: Keystone of tissue homeostasis and pathology in inflammation and ageing

Fibroblasts, derived from the embryonic mesenchyme, are a diverse array of cells with roles in development, homeostasis, repair, and disease across tissues. In doing so, fibroblasts maintain micro-environmental homeostasis and create tissue niches by producing a complex extracellular matrix (ECM) including various structural proteins. Although long considered phenotypically homogenous and functionally identical, the emergence of novel technologies such as single cell transcriptomics has allowed the identification of different phenotypic and cellular states to be attributed to fibroblasts, highlighting their role in tissue regulation and inflammation. Therefore, fibroblasts are now recognised as central actors in many diseases, increasing the need to discover new therapies targeting those cells. Herein, we review the phenotypic heterogeneity and functionality of these cells and their roles in health and disease.

An update on epigenetic regulation in autoimmune diseases

Autoimmune diseases (AIDs) generally manifest as chronic immune disorders characterized by significant heterogeneity and complex symptoms. The discordant incidence of AIDs between monozygotic twins guided people to attach importance to environmental factors. Epigenetics is one of the major ways to be influenced, some of them can even occur years before clinical diagnosis. With the advent of high-throughput omics times, the mysterious veil of epigenetic modification in AIDs has been gradually unraveled, and some progress has been made in utilizing it as indicators of diagnosis and disease activity. For example, the hypomethylated IFI44L promoter in diagnosing systematic lupus erythematosus (SLE). More recently, newly identified noncoding RNAs (ncRNAs), including long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), are also believed to be involved in the etiology of AIDs while the initial factor behind those epigenetic alterations can be diverse from metabolism to microbiota. Update and comprehensive insights into epigenetics in AIDs can help us understand the pathogenesis and further orchestrate it to benefit patients in the future. Therefore, we reviewed the latest epigenetic findings in SLE, rheumatoid arthritis (RA), Type 1 diabetes (T1D), systemic sclerosis (SSc) primarily from cellular levels.

Serinc2 deficiency causes susceptibility to sepsis-associated acute lung injury

Background

Severe sepsis and its subsequent complications cause high morbidity and mortality rates worldwide. The lung is one of the most vulnerable organs sensitive to the sepsis-associated inflammatory storm and usually develops into acute respiratory distress syndrome (ARDS)/acute lung injury (ALI). The pathogenesis of sepsis-associated ALI is accompanied by coordinated transmembrane signal transduction and subsequent programmed cell death; however, the underlying mechanism remains largely unclear.

Results

Here we find that the expression of serine incorporator 2 (Serinc2), a protein involved in phosphatidylserine synthesis and membrane incorporation, is upregulated in cecal ligation and puncture (CLP)-induced ALI. Furthermore, the Serinc2-knockout (KO) mouse line is generated by the CRISPR-cas9 approach. Compared with wild-type mice, the Serinc2-KO mice exhibit exacerbated ALI-related pathologies after CLP. The expressions of pro-inflammatory factors, including IL1β, IL6, TNFα, and MCP1, are significantly enhanced by Serinc2 deficiency, concurrent with over-activation of STAT3, p38 and ERK pathways. Conversely, Serinc2 overexpression in RAW264.7 cells significantly suppresses the inflammatory responses induced by lipopolysaccharide (LPS). Serinc2 KO aggravates CLP-induced apoptosis as evidenced by increases in TUNEL-positive staining, Bax expression, and cleaved caspase-3 and decreases in BCL-2 expression and Akt phosphorylation, whereas these changes are suppressed by Serinc2 overexpression in LPS-treated RAW264.7 cells. Moreover, the administration of AKTin, an inhibitor of Akt, abolishes the protective effects of Serinc2 overexpression against inflammation and apoptosis.

Conclusions

Our findings demonstrate a protective role of Serinc2 in the lung through activating the Akt pathway, and provide novel insight into the pathogenesis of sepsis-induced ALI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12950-022-00306-x.

Triptolide improves chondrocyte proliferation and secretion via down-regulation of miR-221 in synovial cell exosomes

BACKGROUND

Rheumatoid arthritis (RA), the most common type of inflammatory arthritis, can cause bone damage and disability. Triptolide, a prominent treatment for RA, has satisfactory anti-inflammatory effects. However, the mechanism of action of triptolide in RA remains unknown.

PURPOSE

This study aimed to explore the molecular mechanisms underlying triptolide-mediated improvements in RA and identify the miRNA pathway responsible for these effects.

METHODS

We identified various dysregulated miRNAs associated with RA by mining previously described microarray data and verified and screened these candidates using RT-qPCR. Hematoxylin-eosin staining was then applied to identify pathological changes in the affected joints, and cell counting kit-8 analysis and flow cytometry were employed to examine cell proliferation and apoptosis, respectively. Extracted exosomes were verified using transmission electron microscopy.

RESULTS

Our results revealed that the legs of rats with collagen-induced arthritis presented with obvious swelling and bone damage, a high degree of inflammatory cell infiltration into the synovium, and structural changes to the cartilage. Data mining identified 39 dysregulated miRNAs in these tissues, and RT-qPCR further refined these observations to highlight miR-221 as a potential RA biomarker. Subsequent evaluations revealed that fibroblast-like synovial (FLS) cells secrete Exs carrying dysregulated miR-221 in vitro. These Exs mediate miR-221 levels, inflammation, and TLR4/MyD88 signaling via their fusion with chondrocytes, leading to changes in chondrocyte growth and metabolic factor levels. Additionally, the addition of triptolide impaired miR-221 expression, cell proliferation, inflammatory factors, and the protein levels of TLR4/MyD88 in RA-FLS and promoted the apoptosis of FLS. The therapeutic effect of triptolide on miR-221 Exs was reversed by miR-221 inhibitor in both normal and RA FLS.

CONCLUSION

Our research shows that effective treatment with triptolide is mediated by its regulation of growth and secretory functions of chondrocytes via the inhibition of miR-221 secretion by FLS, providing a new target and natural medicinal candidate for future RA treatments.

Role of microRNA in Endocrine Disruptor-Induced Immunomodulation of Metabolic Health

The prevalence of poor metabolic health is growing exponentially worldwide. This condition is associated with complex comorbidities that lead to a compromised quality of life. One of the contributing factors recently gaining attention is exposure to environmental chemicals, such as endocrine-disrupting chemicals (EDCs). Considerable evidence suggests that EDCs can alter the endocrine system through immunomodulation. More concerning, EDC exposure during the fetal development stage has prominent adverse effects later in life, which may pass on to subsequent generations. Although the mechanism of action for this phenomenon is mostly unexplored, recent reports implicate that non-coding RNAs, such as microRNAs (miRs), may play a vital role in this scenario. MiRs are significant contributors in post-transcriptional regulation of gene expression. Studies demonstrating the immunomodulation of EDCs via miRs in metabolic health or towards the Developmental Origins of Health and Disease (DOHaD) Hypothesis are still deficient. The aim of the current review was to focus on studies that demonstrate the impact of EDCs primarily on innate immunity and the potential role of miRs in metabolic health.

Attenuation of Palmitic Acid-Induced Intestinal Epithelial Barrier Dysfunction by 6-Shogaol in Caco-2 Cells: The Role of MiR-216a-5p/TLR4/NF-κB Axis

Palmitic acid (PA) can lead to intestinal epithelial barrier dysfunction. In this study, the protective effects and working mechanisms of 6-shogaol against PA-induced intestinal barrier dysfunction were investigated in human intestinal epithelial Caco-2 cells. Transepithelial electrical resistance (TEER), paracellular flux, qRT-PCR, immunofluorescence, and Western blot experiments showed that the 24-h treatment with 400 μM PA damaged intestinal barrier integrity, as evidenced by a reduction of 48% in the TEER value, a 4.1-fold increase in the flux of fluorescein isothiocyanate-dextran 4000 (FD-4), and decreases in the mRNA and protein expression of tight junction (TJ)-associated proteins (claudin-1, occludin, and ZO-1), compared with the control. The PA treatment significantly (p < 0.05) increased the levels of pro-inflammatory cytokines (interleukin (IL)-6, IL-1β, and tumor necrosis factor-alpha (TNF-α)) in Caco-2 cells due to the upregulation of toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), phosphorylated nuclear factor kappa-B (NF-κB) proteins, and downregulation of miR-216a-5p (which directly targeted TLR4). Co-treatment with PA and 6-shogaol (2.5 μM) significantly (p < 0.05) attenuated PA-induced changes through regulation of TJs via the miR-216a-5p/TLR4/NF-κB signaling pathway. This study provides insights into the functions and working mechanisms of 6-shogaol as a promising food-derived agent against PA-induced intestinal epithelial barrier dysfunction.

Dehydrocorydaline Accelerates Cell Proliferation and Extracellular Matrix Synthesis of TNFα-Treated Human Chondrocytes by Targeting Cox2 through JAK1-STAT3 Signaling Pathway

Osteoarthritis (OA) causes severe degeneration of the meniscus and cartilage layer in the knee and endangers joint integrity and function. In this study, we utilized tumor necrosis factor α (TNFα) to establish in vitro OA models and analyzed the effects of dehydrocorydaline (DHC) on cell proliferation and extracellular matrix (ECM) synthesis in human chondrocytes with TNFα treatment. We found that TNFα treatment significantly reduced cell proliferation and mRNA and protein expression levels of aggrecan and type II collagen, but caused an increase in mRNA and protein expression levels of type I collagen, matrix metalloproteinase 1/13 (MMP1/13), and prostaglandin-endoperoxide synthase 2 (PTGS2, also known as Cox2) in human chondrocytes. DHC significantly promoted the cell activity of normal human chondrocytes without showing cytotoxity. Moreover, 10 and 20 μM DHC clearly restored cell proliferation, inhibited mRNA and protein expression levels of type I collagen, MMP 1/13, and Cox2, and further increased those of aggrecan and type II collagen in the TNFα-treated human chondrocytes. RNA transcriptome sequencing indicated that DHC could improve TNFα-induced metabolic abnormalities and inflammation reactions and inhibit the expression of TNFα-induced inflammatory factors. Furthermore, we found that the JAK1-STAT3 signaling pathway was confirmed to be involved in the regulatory effects of DHC on cell proliferation and ECM metabolism of the TNFα-treated human chondrocytes. Lastly, to explore the effects of DHC in vivo, we established an anterior cruciate ligament transection (ACLT)-stimulated rat OA model and found that DHC administration significantly attenuated OA development, inhibited the enzymatic hydrolysis of ECM, and reduced phosphorylated JAK1 and STAT3 protein expression in vivo after ACLT for 6 weeks. These results suggest that DHC can effectively relieve OA progression, and it has a potential to be utilized for the clinical prevention and therapy of OA as a natural small molecular drug.

STAT3 pathway in cancers: Past, present, and future

Signal transducer and activator of transcription 3 (STAT3), a member of the STAT family, discovered in the cytoplasm of almost all types of mammalian cells, plays a significant role in biological functions. The duration of STAT3 activation in normal tissues is a transient event and is strictly regulated. However, in cancer tissues, STAT3 is activated in an aberrant manner and is induced by certain cytokines. The continuous activation of STAT3 regulates the expression of downstream proteins associated with the formation, progression, and metastasis of cancers. Thus, elucidating the mechanisms of STAT3 regulation and designing inhibitors targeting the STAT3 pathway are considered promising strategies for cancer treatment. This review aims to introduce the history, research advances, and prospects concerning the STAT3 pathway in cancer. We review the mechanisms of STAT3 pathway regulation and the consequent cancer hallmarks associated with tumor biology that are induced by the STAT3 pathway. Moreover, we summarize the emerging development of inhibitors that target the STAT3 pathway and novel drug delivery systems for delivering these inhibitors. The barriers against targeting the STAT3 pathway, the focus of future research on promising targets in the STAT3 pathway, and our perspective on the overall utility of STAT3 pathway inhibitors in cancer treatment are also discussed.

RND3 Transcriptionally Regulated by FOXM1 Inhibits the Migration and Inflammation of Synovial Fibroblasts in Rheumatoid Arthritis Through the Rho/ROCK Pathway

Rheumatoid arthritis (RA) is a systemic immune disease. Rho family GTPase 3 (RND3) has been reported to play an important role in inflammatory diseases. In this study, the expression of RND3 in RA was analyzed by gene chips. After RND3 was overexpressed, cell counting kit-8 assay was to detect the viability of fibroblast-like synovial cells (RA-FLSs). Transwell assays were to appraise the migratory and invasive capacities of RA-FLSs. Enzyme-linked immunosorbent assay (ELISA) and Western blot analysis were to estimate inflammatory response. In addition, MMP3 and MMP9 levels were also tested by ELISA analysis. After forkhead box M1 (FOXM1) was overexpressed, RND3 expression was detected by Western blot. The transcriptional relationship between FOXM1 and RND3 was predicted by HumanTFDB and JASPAR databases. Luciferase reporter and chromatin immunoprecipitation assays verified the binding ability of FOXM1 and RND3. The role of FOXM1/RND3 axis in RA was detected again by functional experiments. Western blot detected the expression of Rho/ROCK pathway-related proteins. RND3 expression was downregulated in RA. Overexpression of RND3 reduced the proliferation, migration, invasion, and inflammation of RA-FLSs. RND3 was inhibited by FOXM1 transcription, and upregulated FOXM1 reduced the inhibitory effect of RND3 overexpression on cell growth and inflammation, which might be associated with the Rho/ROCK pathway. RND3 transcriptionally regulated by FOXM1 inhibited the migration and inflammation of RA-FLSs in RA through the Rho/ROCK pathway.

MicroRNA-122-3p plays as the target of long non-coding RNA LINC00665 in repressing the progress of arthritis

MicroRNAs (miRNAs) play important roles in many diseases, including rheumatoid arthritis (RA). However, the mechanisms underlying the effects of miR-122-3p-3p on RA are not distinct and require further investigation. Patients with RA and healthy controls were recruited to analyze the miR-122-3p levels. The MH7A cells were stimulated with interleukin (IL)-1β to mimic the local inflammation of RA. Cell Counting Kit-8 (CCK-8) and flow cytometry were performed to measure the viability and apoptosis of MH7A cells. Diana tools and TargetScan were used to predict the target relationships. Luciferase reporter assay was used to validate the target relationship. miR-122-3p is downregulated in RA patients and IL-1β-stimulated MH7A cells. miR-122-3p suppresses MH7A cell viability and promotes MH7A cell apoptosis. miR-122-3p targets LINC00665. LINC00665 eliminates the inhibitory effect of miR-122-3p on IL-1β-stimulated MH7A cells. Eukaryotic translation initiation factor 2 alpha kinase 1 (EIF2AK1) targets miR-122-3p. In addition, EIF2AK1 is highly expressed in patients with RA. In addition, EIF2AK1 activates the mTOR signaling pathway. miR-122-3p represses RA progression by reducing cell viability and increasing synoviocyte apoptosis.

RA Fibroblast-Like Synoviocytes Derived Extracellular Vesicles Promote Angiogenesis by miRNA-1972 Targeting p53/mTOR Signaling in Vascular Endotheliocyte

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammatory in joints. Invasive pannus is a characteristic pathological feature of RA. RA fibroblast-like synoviocytes (FLSs) are showed tumor-like biological characters that facilitate pannus generation. Importantly, it has been documented that extracellular vesicle (EVs) derived microRNAs have a vital role of angiogenesis in various immune inflammatory diseases. However, whether RA FLSs derived EVs can facilitate angiogenesis and the underlying mechanism is undefined. Herein, we aim to investigate the key role of RA FLSs derived EVs on angiogenesis in endothelial cells (ECs). We indicate that RA FLSs derived EVs promote ECs angiogenesis by enhancing migration and tube formation of ECs in vitro. Also, we confirm that RA FLSs derived EVs can significantly facilitate ECs angiogenesis with a matrigel angiogenesis mice model. In terms of the mechanisms, both RNAs and proteins in EVs play roles in promoting ECs angiogenesis, but the RNA parts are more fundamental in this process. By combining microRNA sequencing and qPCR results, miR-1972 is identified to facilitate ECs angiogenesis. The blockage of miR-1972 significantly abrogated the angiogenesis stimulative ability of RA FLSs derived EVs in ECs, while the overexpression of miR-1972 reversed the effect in ECs. Specifically, the p53 level is decreased, and the phosphorylated mTOR is upregulated in miR-1972 overexpressed ECs, indicating that miR-1972 expedites angiogenesis through p53/mTOR pathway. Collectively, RA FLSs derived EVs can promote ECs angiogenesis via miR-1972 targeted p53/mTOR signaling, targeting on RA FLSs derived EVs or miR-1972 provides a promising strategy for the treatment of patients with RA.

Epigenetic Regulation in the Pathogenesis of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease. The etiology of RA remains undetermined and the pathogenesis is complex. There remains a paucity of ideal therapeutic drugs and treatment strategies. The epigenetic modifications affect and regulate the function and characteristics of genes through mechanisms, including DNA methylation, histone modification, chromosome remodeling, and RNAi, thereby exerting a significant impact on the living state of the body. Recently, the phenomenon of epigenetic modification in RA has garnered growing research interest. The application of epigenetically modified methods is the frontier field in the research of RA pathogenesis. This review highlights the research on the pathogenesis of RA based on epigenetic modification in the recent five years, thereby suggesting new methods and strategies for the diagnosis and treatment of RA.