Pro-fibrotic effect of the susceptible gene PCSK5 in vascular fibrosis of Takayasu arteritis via TGF-ß and SMAD3 signaling pathway activation.

BACKGROUND: Vascular fibrosis directly causes vascular thickening in Takayasu arteritis (TAK), in which sustained transforming growth factor beta (TGF-ß) activation is critical. Understanding TGF-ß activation regulation and blocking it might yield a therapeutic effect in TAK. Proprotein convertase subtilisin/kexin type 5 (PCSK5) rs6560480 (T/C) is associated with TAK development. In this study, we assessed the association between the PCSK5 rs6560480 genotype and PCSK5 expression in TAK and explored its molecular role in TGF-ß activation and vascular fibrosis development. METHODS: In TAK patients, PCSK5 and TGF-ß expression in plasma and aortic tissue was examined by ELISA and immunohistochemical staining, and PCSK5 rs6560480 was genotyped. The correlation between PCSK5 and extracellular matrix (ECM) expression was examined by Western blotting (WB) and immunohistochemistry staining. Detection by co-immunoprecipitation was performed to detect the interaction between PCSK5 and TGF-ß in adventitial fibroblasts (AAFs). Downstream signaling pathways were detected by WB and validated with appropriate inhibitors. Potential immunosuppressive agents to inhibit the effects of PCSK5 were explored in cell culture and TAK patients. RESULTS: Patients with PCSK5 rs6560480 TT patients had significantly higher PCSK5 levels and more thickened vascular lesions than patients with PCSK5 rs6560480 CT. PCSK5 expression was significantly increased in alpha smooth muscle actin (α-SMA)-positive myofibroblasts in TAK vascular lesions. Overexpressing PCSK5 facilitated TGF-ß and downstream SMAD2/3 activation and ECM expression in AAFs and aorta in in-vitro culture. The mechanistic study supported that PCSK5 activated precursor TGF-ß (pro-TGF-ß) to the mature form by binding the pro-TGF-ß cleavage site. Leflunomide inhibited PCSK5 and pro-TGF-ß binding, decreasing TGF-ß activation and ECM expression, which was also partially validated in leflunomide-treated patients. CONCLUSION: The findings revealed a novel pro-fibrotic mechanism of PCSK5 in TAK vascular fibrosis via TGF-ß and downstream SMAD2/3 pathway activation. Leflunomide might be anti-fibrotic by disrupting PCSK5 and pro-TGF-ß binding, presenting a new TAK treatment approach.

Resolution of Plaque Keratopathy in a Patient with Atopic Keratoconjunctivitis After Treatment with Leflunomide.

PURPOSE: To report a case of resolution of corneal findings in a patient with atopic keratoconjunctivitis after treatment with leflunomide. METHODS: Case report. RESULTS: A 57-year-old male presented with ocular signs and symptoms consistent with severe atopic keratoconjunctivitis. His case was distinguished by impressive sub-epithelial Salzmann-like nodules in the shape of petaloid plaques in both eyes. These keratinized plaques persisted despite topical steroids, tacrolimus ointment, and routine subconjunctival triamcinolone injections. The patient was started on leflunomide 10 mg daily for seropositive rheumatoid arthritis with rapid subsequent improvement in his symptoms, vision, and keratopathy. The patient has remained stable on oral leflunomide. CONCLUSION: To the authors' knowledge, this is the first case report to describe rapid resolution of "plaque keratopathy" and improvement of AKC with leflunomide treatment. Further work remains to be done to elucidate the role of disease-modifying drugs in atopic keratoconjunctivitis.

Leflunomide-Associated Wound Complication After Cochlear Implantation: A Case Report.

INTRODUCTION: Cochlear implantation has become an increasingly common strategy for aural rehabilitation in patients with severe to profound hearing loss who no longer benefit from conventional amplification. In conjunction, immunosuppressive therapies (e.g. disease-modifying anti rheumatic drugs (DMARDs) have become the keystone of management in numerous autoimmune conditions. Given the increasing prevalence of both, a greater proportion of patients will undergo cochlear implantation while on immune-modulating medications. While these medications are usually well tolerated, immunosuppression may put patients a higher risk for device infections. At present, this is not extensively studied within the cochlear implant literature. METHODS: We conducted a retrospective chart review and review of the literature.Results:We present the case of an 81-year-old male who experienced wound dehiscence and infection secondary to leflunomide use for treatment of rheumatoid arthritis. Resolution of these issues was noted with a therapeutic drug holiday, and the patient has subsequently undergone re-implantation without issue.Conclusions:The case highlights a potential CI-associated wound complication in the setting of DMARD therapy. Given the increasing prevalence of both CIs and immunosuppressive therapy, future study on the potential for interaction is warranted to identify the best management strategy in the perioperative setting.

Study on the Mechanism of the Combination of Methotrexate and Leflunomide in the Treatment of Rheumatoid Arthritis Based on Network Pharmacology, Molecular Docking, and in vitro Experimental Verification.

BACKGROUND: To date, disease-modifying antirheumatic drugs (DMARDs) are widely used as the primary first-line treatment option for patients with rheumatoid arthritis (RA), and the curative effect of methotrexate (MTX) and leflunomide (LEF; MTX + LEF) is greater than that of single-agent MTX therapy, but the synergistic mechanism of MTX + LEF is unclear. METHODS: First, we explored the mechanism of action of MTX + LEF in RA through network pharmacology and molecular docking. Venn diagram analysis revealed 97 overlapping gene targets of MTX + LEF-RA and STRING, along with Cytoscape plug-in MOCDE and cytoHubba; and GO enrichment analysis revealed that the functions of 97 synergistic targets were related to 123 molecular functions (MF), 63 cell components (CC), and 1,068 biological processes (BP). The Cytoscape plug-in ClueGO demonstrated that these targets were enriched in KEGG pathways of 52 terms, whereas 9 pivotal genes were mainly involved in the signaling pathways of estrogen, Ras, Rap1, PI3K-Akt, relaxin, TNF, AMPK, FoxO, prolactin, IL-17, and adherens junction. Finally, CETSA and DARTS validated the direct binding of MTX or LEF to the selected target proteins EGFR, PPARG, MMP9, and SRC in RAW264.7 cells. RESULTS: We identified 292 MTX targets and 247 LEF targets from 7 databases. Furthermore, 2,814 potential targets of RA were identified by merging 1,925 targets from 7 databases and 999 differentially expressed genes (DEGs) between normal controls and patients with RA extracted from 5 GEO databases. Nine pivotal genes, ESR1, ALB, CASP3, EGFR, HSP90AA1, SRC, MMP9, PPARG, and IGF1, were identified. Molecular docking verified that both MTX and LEF strongly bind to most of the 9 pivotal proteins except ESR1 and IGF1. CONCLUSION: These results contribute to our understanding of the enhancement mechanism of MTX combined with LEF and provide a targeted basis for the clinical treatment of RA.

Microscopic Colitis Secondary to Leflunomide: A Case Report.

Microscopic colitis (MC) is characterized by chronic watery diarrhea that requires histological examination for diagnosis. Here, we present a case of a 63-year-old female with rheumatoid arthritis who developed persistent diarrhea following leflunomide initiation. Despite a normal colonoscopy, random colonic biopsies confirmed MC. Discontinuation of leflunomide led to symptom resolution, implicating it as the causative agent. Leflunomide-induced MC is exceedingly rare, with limited documented cases. Understanding its variability in presentation and timely recognition is crucial. This case underscores the importance of thorough medication history assessment and consideration of drug-induced colitis in patients presenting with unexplained diarrhea, facilitating prompt management and resolution.

Leflunomide Treatment Does Not Protect Neural Cells following Oxygen-Glucose Deprivation (OGD) In Vitro.

Neonatal hypoxia-ischemia (HI) affects 2-3 per 1000 live births in developed countries and up to 26 per 1000 live births in developing countries. It is estimated that of the 750,000 infants experiencing a hypoxic-ischemic event during birth per year, more than 400,000 will be severely affected. As treatment options are limited, rapidly identifying new therapeutic avenues is critical, and repurposing drugs already in clinical use offers a fast-track route to clinic. One emerging avenue for therapeutic intervention in neonatal HI is to target mitochondrial dysfunction, which occurs early in the development of brain injury. Mitochondrial dynamics are particularly affected, with mitochondrial fragmentation occurring at the expense of the pro-fusion protein Optic Atrophy (OPA)1. OPA1, together with mitofusins (MFN)1/2, are required for membrane fusion, and therefore, protecting their function may also safeguard mitochondrial dynamics. Leflunomide, an FDA-approved immunosuppressant, was recently identified as an activator of MFN2 with partial effects on OPA1 expression. We, therefore, treated C17.2 cells with Leflunomide before or after oxygen-glucose deprivation, an in vitro mimic of HI, to determine its efficacy as a neuroprotection and inhibitor of mitochondrial dysfunction. Leflunomide increased baseline OPA1 but not MFN2 expression in C17.2 cells. However, Leflunomide was unable to promote cell survival following OGD. Equally, there was no obvious effect on mitochondrial morphology or bioenergetics. These data align with studies suggesting that the tissue and mitochondrial protein profile of the target cell/tissue are critical for taking advantage of the therapeutic actions of Leflunomide.

Leflunomide with prednisone or nonsteroidal anti-inflammatory drug therapy is safe and tolerated for long-term treatment of immune-mediated polyarthritis in 27 dogs.

OBJECTIVE: To retrospectively evaluate safety and tolerance of leflunomide for long-term treatment of canine idiopathic immune-mediated polyarthritis (IMPA). ANIMALS: 27 dogs with clinical signs and synovial fluid cytology supportive of IMPA with ≥ 6 months' follow-up after starting leflunomide. METHODS: Medical records were reviewed to identify dogs prescribed leflunomide for treatment of IMPA from February 2012 to May 2022. Initial leflunomide doses of 2 to 4 mg/kg once daily were prescribed and were titrated to the lowest effective dose with concurrent anti-inflammatory therapy. Complete blood count, serum chemistry, and clinical signs were monitored throughout the course of treatment. RESULTS: Adverse effects potentially attributable to leflunomide noted in 9 of 27 dogs (33%) included vomiting, diarrhea, lethargy, decreased or absent appetite, polyuria and polydipsia, and secondary antibiotic responsive infection and were self-limiting or resolved with outpatient therapy. Alkaline phosphatase (ALP) and alanine aminotransferase (ALT) elevation were documented in all dogs prescribed leflunomide plus prednisone, with persistent liver enzyme elevation in 6 of 9 dogs (67%) and normalization after antibiotic therapy in 3 of 9 dogs (33%). The majority of dogs prescribed leflunomide plus NSAID (11/17 [65%] dogs) did not experience liver enzyme elevation; 2 of 17 (12%) dogs developed transient antibiotic-responsive liver enzyme elevations, and 4 of 17 (23%) dogs had persistent liver enzyme elevation. CLINICAL RELEVANCE: Leflunomide was well tolerated for long-term management of IMPA. A significant difference in liver enzyme elevation was identified between dogs prescribed prednisone versus NSAID in combination with leflunomide. Leflunomide with NSAID therapy resulted in less hepatotoxicity compared with leflunomide with prednisone.

OpenSAFELY: The impact of COVID-19 on azathioprine, leflunomide and methotrexate monitoring, and factors associated with change in monitoring rate.

AIMS: The COVID-19 pandemic created unprecedented pressure on healthcare services. This study investigates whether disease-modifying antirheumatic drug (DMARD) safety monitoring was affected during the COVID-19 pandemic. METHODS: A population-based cohort study was conducted using the OpenSAFELY platform to access electronic health record data from 24.2 million patients registered at general practices using TPP's SystmOne software. Patients were included for further analysis if prescribed azathioprine, leflunomide or methotrexate between November 2019 and July 2022. Outcomes were assessed as monthly trends and variation between various sociodemographic and clinical groups for adherence with standard safety monitoring recommendations. RESULTS: An acute increase in the rate of missed monitoring occurred across the study population (+12.4 percentage points) when lockdown measures were implemented in March 2020. This increase was more pronounced for some patient groups (70-79 year-olds: +13.7 percentage points; females: +12.8 percentage points), regions (North West: +17.0 percentage points), medications (leflunomide: +20.7 percentage points) and monitoring tests (blood pressure: +24.5 percentage points). Missed monitoring rates decreased substantially for all groups by July 2022. Consistent differences were observed in overall missed monitoring rates between several groups throughout the study. CONCLUSION: DMARD monitoring rates temporarily deteriorated during the COVID-19 pandemic. Deterioration coincided with the onset of lockdown measures, with monitoring rates recovering rapidly as lockdown measures were eased. Differences observed in monitoring rates between medications, tests, regions and patient groups highlight opportunities to tackle potential inequalities in the provision or uptake of monitoring services. Further research should evaluate the causes of the differences identified between groups.

Autoantigenic Peptide and Immunomodulator Codelivery System for Rheumatoid Arthritis Treatment by Reestablishing Immune Tolerance.

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by abnormal activation of CD4+ T cells and an imbalance of T helper 17 (Th17) and regulatory T (Treg) cells. Tolerogenic therapy via administration of self-antigens is a promising strategy for RA treatment, but delivery of autoantigens alone may exacerbate disease conditions. Current studies indicated that codelivery of autoantigens with immunomodulators can lead to a more tolerogenic immune response. Here, we constructed an autoantigen type II collagen peptide (CII250-270)- and immunomodulator leflunomide (LEF)-coloaded phosphatidylserine liposome vaccine (CII250-270-LEF-PSL) for RA treatment via induction of tolerant dendritic cells (tolDC) for further activation of Treg cells. The in vivo results showed that CII250-270-LEF-PSL can effectively induce tolDC, regulate the balance of Th1/Th2 and Th17/Treg, and reduce the secretion of pro-inflammatory cytokines (IFN-γ, IL-1ß, and IL-17A) and IgG antibodies to inhibit synovial inflammation and bone erosion. Furthermore, our study also suggested that LEF regulated Th1 cell differentiation by inhibiting the activation of the JAK1/STAT1 signaling pathway, further alleviating RA. Overall, this work proved that the combination of autoantigenic peptides and immunomodulators was a promising modality for RA treatment by reestablishing antigen-specific immune tolerance, which also inspired additional insights into the development of combination therapies for the tolerability of RA.

Effectiveness of methotrexate and leflunomide as corticoid-sparing drugs in patients with polymyalgia rheumatica.

Objectives: The need for glucocorticoid-sparing drugs (GCSD) remains an important issue and is an unmet need in the treatment of polymyalgia rheumatica (PMR). We therefore aimed to assess the effectiveness and safety of methotrexate (MTX) and of leflunomide (LEF) in daily clinical practice in PMR patients from Argentina. Methods: A multicentre and observational study (medical records review) of PMR patients seen between 2007 and 2023, who had at least three months of follow-up after starting a GCSD, either MTX or LEF, was performed. Results are expressed as medians and interquartile ranges [25th-75th (IQR)] for continuous variables and percentages for categorical ones. The two treatment groups were compared using χ2 test for categorical variables, Mann-Whitney U test for continuous variables and the log-rank test for time-to-event data. Crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using logistic regression. In all cases, a p-value <0.05 was considered statistically significant. Results: One-hundred and eighty-six patients (79% female) with a median age of 72 years (IQR, 65-77 years) were included. One-hundred and forty-three patients (77%) were prescribed MTX (15, IQR 10-15) and 43 (23%) LEF (20 mg, fixed dose). Flare-ups (relapses and recurrences) occurred in 13 patients (7%) and were comparable between both groups. Persistent GCSD intake was observed in 145 patients (78%). Glucocorticoid (GC) withdrawal was achieved in 67 of these 145 patients (46%) and this occurred more frequently in the LEF group (P = 0.001). Furthermore, time until prednisone discontinuation was shorter in the LEF-treated patients (4.7 months, IQR 3-20 on LEF versus 31.8 months, IQR 10-82 on MTX, P = 0.000). Remission was found more frequently in the LEF group (P = 0.003). In the multivariate analysis, the probability of remission was higher with LEF therapy (P = 0.010) and this finding persisted in the subgroup analysis who were followed up < 40 months (OR 3.12, 95% CI = 1.30-7.47, P = 0.011). Conclusions: This study demonstrated the clinical effectiveness of LEF and even its superiority in achieving remission when compared with MTX as GCSD in PMR patients. Further research is needed to support these findings.

Vulnerability of Store-Operated Calcium Entry to Inhibitors and Microenvironment in Cells of Different Breast Cancer Subtypes.

The incidence and development of cancer are highly dependent on pathological disturbances in calcium homeostasis of the cell. One of the major pathways for calcium entry is store-operated calcium entry (SOCE), which functions in virtually all cell types. Changes in the expression level of the main proteins organizing SOCE are observed during the development of various cancer types, particularly breast cancer (BC). This leads to unique SOCE with characteristics individual for each type of BC and requires particular therapeutic approaches. In this study, we tested the sensitivity of SOCE in various BC cells to selective ORAI channel inhibitors and the less selective compounds Leflunomide and Teriflunomide, approved by the FDA for clinical use. We also analyzed the vulnerability of SOCE to the influence of factors typical of the tumor microenvironment: hypoxia and acidification. We have observed that the SOCE inhibitors Leflunomide and Teriflunomide suppress SOCE in the triple-negative BC cell line MDA-MB-231, but not in the luminal A BC cell line MCF-7. MDA-MB-231 cells also demonstrate higher pH dependence of SOCE compared to MCF-7 cells. In addition, the oxygen scavenger sodium dithionide also affects SOCE, stimulating it in MDA-MB-231 cells but inhibiting in MCF-7 cells. Overall, our data highlight the importance of considering the different sensitivities of various BC cell types to inhibitors and to microenvironmental factors such as hypoxia and acidification when developing targeted drugs.

Use of leflunomide among girls and women of childbearing age and occurrence of leflunomide-exposed pregnancies in Germany.

Leflunomide is contraindicated during pregnancy and treatment cessation is recommended two years before pregnancy. We aimed to describe leflunomide use in women of childbearing age in Germany, the occurrence of pregnancies in women using leflunomide and malformations among children possibly exposed in utero. Using the GePaRD database (claims data, ∼20% of the German population), we determined annual age-standardized prevalences of leflunomide use between 2004 and 2019 among females aged 13-49 years. Further, we estimated the number of exposed pregnancies by assessing whether the exposure window assigned to the last dispensation before pregnancy (days covered by the dispensation plus two years) overlapped the onset of pregnancy or whether there was a dispensation in the first eight weeks of pregnancy. For exposed live births, a mother-baby linkage was performed and the presence of congenital malformation was assessed. The age-standardized prevalence of leflunomide use ranged between 0.34 and 0.46 per 1000 females during the study period. About one third of the users were ≤40 years. We identified 205 leflunomide-exposed pregnancies ending during the study period. 71% of these pregnancies ended in a live birth (26% preterm) and 10% in an induced abortion. In 86% of the live births (n=125) the mother-baby linkage was successful. Among these 125 children, 13 children (10%) had congenital malformations. In conclusion, we observed a considerable number of pregnancies in women using leflunomide in the two years before or during early pregnancy. This highlights the importance of monitoring the implementation of existing risk minimization measures for leflunomide in Germany.

Synergistic impact of Gui Zhi Shao Yao Zhi Mu Decoction and leflunomide on gut microbiota in rheumatoid arthritis: insights from 16S rDNA sequencing.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disease with complex pathogenesis, including alterations in the gut microbiota. Gui Zhi Shao Yao Zhi Mu Decoction (GSZD), a traditional Chinese herbal formula, has shown efficacy in RA treatment, but its impact on intestinal microflora remains unclear. This study aimed to investigate the effects of GSZD combined with leflunomide on the gut microbiota of RA patients. METHODS: The study enrolled 48 RA patients who were randomly assigned to either a control group receiving leflunomide or a treatment group receiving GSZD combined with leflunomide for 12 weeks. Gut microbiota composition was analyzed pre- and post-intervention using 16S rDNA sequencing. Changes in microbial diversity, abundance, and metabolic functions were assessed. RESULTS: Post-treatment, both groups exhibited significant alterations in gut microbiota composition. GSZD combined with leflunomide led to an increased Bacteroidetes/Firmicutes ratio and a reduction in Actinobacteria compared to leflunomide alone. This was associated with beneficial shifts in microbial genera and metabolic pathways, suggesting improved gut health and systemic immune modulation. CONCLUSION: GSZD combined with leflunomide significantly modulates the gut microbiota in RA patients. This study provides insights into the mechanisms underlying the therapeutic effects of GSZD and highlights the potential of integrating traditional Chinese medicine with conventional treatments in managing RA.

Efficacy and safety of low-dose corticosteroids combined with leflunomide for progressive IgA nephropathy: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: The effectiveness of immunosuppressive and corticosteroid treatments for Immunoglobulin A (IgA) nephropathy (IgAN) remains thoroughly evaluated. We undertook a meta-analysis to investigate the efficacy and safety of low-dose corticosteroids plus leflunomide for progressive IgA nephropathy. METHODS: Eligible studies were obtained from PubMed, Embase, and Cochrane Library databases. We also searched the references of the included studies. Our protocol followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) checklist. Eligibility criteria were defined using a PICOS framework. RESULTS: Our study included three articles presenting 342 patient cases. Findings revealed that low-dose corticosteroids combined with the leflunomide group were effective in relieving urine protein excretion (UPE) [mean difference (MD) = -0.35, 95% confidence interval (CI): -0.41 to -0.30, P < 0.00001] compared with the full-dose corticosteroids group. Regarding serum creatinine (SCr), estimated glomerular filtration rate (eGFR), complete remission rate, and overall response rate, there was no difference between the groups (p > 0.05). Regarding safety, low-dose corticosteroids combined with leflunomide significantly reduced the risk of serious adverse events [odds ratio (OR): 0.11, 95% CI: 0.01 to 0.91, P = 0.04]. Besides, no significant differences were observed between the two groups in the incidence of respiratory infection, abnormal liver function, diarrhea, herpes zoster, alopecia, pruritus, insomnia, pneumonia, diabetes, and urinary tract infection (P > 0.05). CONCLUSIONS: Low-dose corticosteroids combined with leflunomide are a safe and effective treatment for progressive IgA nephropathy. TRIAL REGISTRATION: The PROSPERO registration number is CRD42022361883.

Leflunomide-induced cardiac injury in adult male mice and bioinformatic approach identifying Nrf2/NF-κb signaling interplay.

Leflunomide (LFND) is an immunosuppressive and immunomodulatory disease-modifying antirheumatic drug (DMARD) that was approved for treating rheumatoid arthritis. LFND-induced cardiotoxicity was not fully investigated since its approval. We investigated the cardiac injury in male mice and identified the role of nuclear factor erythroid 2-related factor 2/nuclear factor-κ B (Nrf2/NF-κB) signaling. Male albino mice were assigned into five groups as control, vehicle, and LFND (2.5, 5, and 10 mg/kg). We investigated cardiac enzymes, histopathology, and the mRNA expression of Nrf2, NF-κB, BAX, and tumor necrosis factor-α (TNF-α). The bioinformatic study identified the interaction between LFND and Nrf2/NF-κB signaling; this was confirmed by amelioration in mRNA expression (0.5- to 0.34-fold decrease in Nrf2 and 2.6- to 4.61-fold increases in NF-κB genes) and increased (1.76- and 2.625-fold) serum creatine kinase (CK) and 1.38- and 2.33-fold increases in creatine kinase-MB (CK-MB). Histopathological results confirmed the dose-dependent effects of LFND on cardiac muscle structure in the form of cytoplasmic, nuclear, and vascular changes in addition to increased collagen deposits and apoptosis which were increased compared to controls especially with LFND 10 mg/kg. The current study elicits the dose-dependent cardiac injury induced by LFND administration and highlights, for the first time, dysregulation in Nrf2/NF-κB signaling.

Seasonal and Treatment-Related Variation in 25-Hydroxy Vitamin D Concentration in Patients with Rheumatoid Arthritis.

Background/Objectives: 25-hydroxy vitamin D (25-OH-D) is a fat-soluble compound that plays many essential functions, including bone formation, neuromuscular functions, and prevention of osteoporosis and inflammation. Recent data indicate that its metabolites are associated with rheumatoid arthritis (RA) progression and neuropathic pain in RA patients. We aimed to assess the effect of RA pharmacotherapy and seasonal variation on serum levels of 25-OH-D in RA patients who received treatment with methotrexate (MTX) or leflunomide (LEF) for at least one year. Methods: This study is a retrospective analysis of data collected from 101 patients with RA who received treatment for at least one year. All of them have supplemented 25-OH-D (2000 IU daily) for at least one year. Results: We observed a significant seasonal variation in 25-OH-D concentration (p = 0.004). Moreover, there were significant differences (p = 0.03) between LEF (50.63 ± 17.73 ng/mL) and MTX (34.73 ± 14.04 ng/mL) treatment groups, but only for the summer population. A correlation was observed between 25-OH-D and RA duration-once again, in the summer population (the whole group-r = -0.64; treatment subgroups-r = -0.82 for LEF and -0.61 for MTX). Deficiency of 25-OH-D (below 20 ng/mL) was confirmed in 28.7% of patients, while 18.8% had suboptimal 25-OH-D levels (20-30 ng/mL). Conclusions: Our results showed that both RA pharmacotherapy and seasonal variation affect the serum levels of 25-OH-D in patients with active RA.

The efficacy and safety of hydroxychloroquine versus leflunomide in patients with IgA nephropathy: a single-center experience.

PURPOSE: To date, our understanding of IgA nephropathy (IgAN) pathophysiology has remained incomplete; therefore, treatment remains largely empiric, and the efficacy and safety of immunosuppressants remain controversial. We aimed to assess the efficacy and safety of hydroxychloroquine and leflunomide therapy in a retrospective cohort of patients with IgAN. METHODS: We screened the IgAN registration database in our department, and a total of 159 kidney patients with biopsy-confirmed IgAN were enrolled, with 57 patients receiving hydroxychloroquine plus a renin-angiotensin system inhibitor (hydroxychloroquine group), 52 patients receiving leflunomide plus a renin-angiotensin system inhibitor (leflunomide group), and 50 patients receiving only a renin-angiotensin system inhibitor (renin-angiotensin system inhibitor-only group). Changes in proteinuria, hematuria, and the estimated glomerular filtration rate (eGFR), as well as adverse events, were analyzed during the follow-up period. RESULTS: At the end of 6-month follow-up, proteinuria significantly decreased by 70.36 (57.54, 79.33)%, 57.29 (46.79, 67.29)% and 41.20 (25.76, 48.94)% in the hydroxychloroquine, leflunomide and renin-angiotensin system inhibitor-only groups, respectively, compared to baseline (all P values < 0.001). Hematuria significantly decreased by 71.07 (56.48, 82.47)% in the leflunomide group (P < 0.001). The eGFR improved by 3.72 ± 2.97%, 3.16 ± 2.00% and 1.91 ± 2.41%, respectively, in the hydroxychloroquine, leflunomide and renin-angiotensin system inhibitor-only groups, but without statistical significance. No serious adverse events occurred during the follow-up period. CONCLUSION: Both hydroxychloroquine combined with a renin-angiotensin system inhibitor and leflunomide combined with a renin-angiotensin system inhibitor were more effective than a renin-angiotensin system inhibitor alone in improving proteinuria in IgAN patients. Hydroxychloroquine was more effective in reducing proteinuria, and leflunomide showed superiority in reducing hematuria. Our results need to be verified in large-scale randomized controlled trials.

Folate decorated chitosan-chondroitin sulfate nanoparticles loaded hydrogel for targeting macrophages against rheumatoid arthritis.

Inflammatory cell infiltration, particularly macrophages, plays a major contribution to the pathogenesis of Rheumatoid Arthritis (RA). Exploiting the overexpression of folate receptors (FR-ß) on these recruited macrophages has gained significant attraction for ligand-targeted delivery. Leflunomide (LEF), being an immunomodulatory agent is considered the cornerstone of the therapy, however, its oral efficacy is impeded by low solubility and escalating adverse effects profile. Therefore, in the present work, we developed Folate-conjugated chitosan-chondroitin sulfate nanoparticles encapsulating LEF for selective targeting at inflammatory sites in RA. For this purpose, the folate group was first conjugated with the chitosan polymer. After which, Folate Leflunomide Nanoparticles (FA-LEF-NPs) were synthesized through the ionotropic gelation method by employing FA-CHI and CHS. The polymers CHI and CHS were also presented with innate anti-inflammatory and anti-rheumatic attributes that were helpful in provision of synergistic effects to the formulation. These nanoparticles were further fabricated into a hydrogel, employing almond oil (A.O) as a permeation enhancer. The in vivo studies justified the preferential accumulation of FA-conjugated nanoparticles at inflamed joints more than any other organ in comparison to the free LEF and LEF-NPs formulation. The FA-LEF-NPs loaded hydrogel also ascertained a minimal adverse effect profile with an improvement of inflammatory cytokines expression.

Leflunomide-induced collagenous colitis: a case report and literature review.

We describe a patient with rheumatoid arthritis and Hashimoto's thyroiditis who developed chronic diarrhea and subsequently diagnosed with collagenous colitis (CC) 5 years after leflunomide initiation. Cessation of leflunomide resulted in complete resolution of diarrhea within 2 months. Although rare, leflunomide-induced colitis should be considered in patients with otherwise unexplained chronic diarrhea. Diagnosis is challenging as symptom onset can occur many years after leflunomide initiation, but diarrheal symptoms typically resolve within weeks to months of stopping the instigating drug.