L-Shaped Associations Between Composite Dietary Antioxidant Index and Hearing Loss: A Cross-Sectional Study From the National Health and Nutrition Examination Survey.

BACKGROUND: Oxidative stress has been implicated in the pathogenesis of hearing loss (HL). Dietary intake is a modifiable factor that could influence the oxidant and antioxidant capacity. We hypothesized that a higher composite dietary antioxidant index (CDAI) is associated with a reduced odds for HL. METHODS: Adult participants from the 2001-2012 & 2015-2018 National Health and Nutrition Examination Study were included in this cross-sectional study. The CDAI was calculated from vitamins A, C, E, selenium, zinc, and caretenoid through 24-h dietary recall. Outcomes were HL, speech frequency HL (SFHL), and high frequency HL (HFHL). The associations between CDAI and HL, SFHL, and HFHL were evaluated by weighted multivariable logistic regression. RESULTS: CDAI was associated with lower odds of HL (OR = 0.98, 95%CI 0.95-1.00, p = .043) and SFHL (OR = 0.97, 95%CI 0.95-1.00, p = .041), but not HFHL (OR = 0.98, 95%CI 0.96-1.00, p = .118) after adjustment for confounders. The multivariable-adjusted model showed a significant trend toward decreased risk of HL, SFHL, and HFHL with increasing CDAI quartile (all p for trend < 0.05). Restricted cubic spline analysis suggested that the associations between CDAI and HL, SFHL, and HFHL were L-shaped, with inflection points of CDAI at -0.61, 2.33, and 4.32, respectively. Subgroup analysis showed that participants with exposure to loud noise benefited from a higher CDAI for SFHL (p for interaction = 0.039). CONCLUSION: Higher CDAI is associated with reduced odds of HL and SFHL in the U.S. adult population and serves as a promising intervention target to be further explored in prospective longitudinal studies in the future.

Associations between the composite dietary antioxidant index and abdominal aortic calcification among United States adults: A cross-sectional study.

BACKGROUND: Oxidative stress has previously been shown to play a pivotal role in the pathogenesis of vascular calcification. In the present study, we aimed to investigate the association between the composite dietary antioxidant index (CDAI) and abdominal aortic calcification (AAC). METHODS: We conducted a cross-sectional study of United States adults using data from the 2013-2014 National Health and Nutrition Examination Survey. The CDAI was calculated from vitamins A, C, E, selenium, zinc, and caretenoid through two rounds of 24-h dietary recall interviews. AAC was assessed by a lateral dual-energy x-ray absorptiometry scan of the thoraco-lumbar spine. The association between CDAI and AAC was evaluated with weighted multivariable logistic regression. RESULTS: Overall, an unweighted 1081 participants were analyzed, including 110 with AAC and 971 without AAC. In the multivariable fully adjusted logistic regression model, CDAI was significantly associated with AAC (odds ratio = 0.89, 95% CI 0.81-0.98; P = 0.02). Compared with the lowest quartile, the highest quartile of CDAI was related to a 0.33-fold risk of AAC (95% CI 0.12-0.90; P = 0.03). Subgroup analysis showed that the significant association between CDAI and AAC was only observed in participants without hypertension (P for interaction = 0.002). CONCLUSION: A higher CDAI was associated with a lower prevalence of AAC among adults without hypertension in the US. Further large-scale prospective studies are required to analyze the protective role of the CDAI in AAC progression.

Estimated glucose disposal rate and risk of cardiovascular disease and mortality in U.S. adults with prediabetes: a nationwide cross-sectional and prospective cohort study.

AIMS: Estimated glucose disposal rate (eGDR), a noninvasive and convenient measure of insulin resistance, has been demonstrated to be associated with mortality in both type 1 and type 2 diabetes. We aimed to explore whether eGDR is associated with cardiovascular disease (CVD) risk and mortality in prediabetic adults. METHODS: A nationwide population-based cohort of prediabetic individuals from the National Health and Nutrition Examination Survey 1999-2018 with available data on eGDR was included and categorized into eGDR ≥ 8 (reference), 6-7.99, 4-5.99, and < 4 mg/kg/min groups. Cox proportional hazards model was used to estimate the associations of eGDR with mortality. RESULTS: A total of 4725 prediabetic adults, 60.12% men, mean age 48 years were included. The odds ratio and 95% confidence interval (CI) for CVD risk were 1.74 (1.08-2.78), 2.90 (1.79-4.67), and 4.58 (2.15-9.76) for the eGDR 6-7.99, 4-5.99, and < 4 mg/kg/min groups, respectively, compared with the reference group. There were 410 deaths (116 CVD-related) during a median follow-up of 107 months in 4,332 participants without baseline CVD. The hazard ratios and 95%CI for the eGDR 6-7.99, 4-5.99, and < 4 mg/kg/min groups were 1.70 (1.23-2.35), 2.01 (1.45-2.77), and 1.84 (1.11-3.04), respectively, for all-cause mortality (P for trend < 0.0001), and 3.84 (2.04-7.21), 4.01 (2.01-8.00), and 2.88 (1.03-8.06), respectively, for CVD mortality (P for trend = 0.01). Smoking status significantly modified the associations between eGDR and all-cause or CVD mortality. CONCLUSIONS: Increased insulin resistance, as indicated by a lower eGDR, is associated with increased risks of all-cause and CVD mortality in U.S. prediabetic adults.

SERPINA3, FGA, AGP1, ITIH3 and SAA1 as novel biomarkers for eosinophilic granulomatosis with polyangiitis diagnosis and activity assessment.

OBJECTIVE: To identify novel biomarkers for diagnosis and prediction of active eosinophilic granulomatosis with polyangiitis (EGPA) through data-independent acquisition (DIA) analysis. METHODS: Plasma from 11 EGPA patients and 10 healthy controls (HCs) were analyzed through DIA to identify potential biomarkers. The results were validated in 32 EGPA patients, 24 disease controls (DCs), and 20 HCs using enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve was used to assess the diagnostic value of candidate biomarkers. RESULTS: Thirty-five differentially expressed proteins (DEPs) (24 upregulated and 11 downregulated) were screened between EGPA and HC groups. Five proteins, including serine proteinase inhibitor A3 (SERPINA3), alpha-fibrinogen (FGA), alpha-1 acid glycoprotein 1(AGP1), inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3), and serum amyloid A1 (SAA1), were significantly upregulated in EGPA compared with HCs. Apart from SAA1, all proteins were also higher in EGPA patients compared with DCs. Furthermore, a panel of SERPINA3 and SAA1 exhibited potential diagnostic value for EGPA with an area under the curve (AUC) of 0.953, while a panel of SERPINA3, FGA, AGP1, and ITIH3 showed good discriminative power to differentiate EGPA from DCs with AUC of 0.926. Moreover, SERPINA3, FGA, and AGP levels were significantly higher in active EGPA and correlated well with disease activity. A combination of SERPINA3 and AGP1 exhibited an excellent AUC of 0.918 for disease activity assessment. CONCLUSION: SERPINA3, FGA, AGP1, ITIH3 and SAA1 were identified as potential biomarkers for EGPA diagnosis and disease activity assessment. Among them, as a single biomarker, SERPINA3 has the best diagnostic performance.

Bibliometric analysis and visualisation of research hotspots and frontiers in Takayasu's arteritis.

OBJECTIVES: Takayasu's arteritis (TAK) is an uncommon granulomatous large-vessel vasculitis associated with significant morbidity and mortality. This study endeavours to comprehend the research status and future frontiers through a bibliometric analysis. METHODS: Relevant original articles published in English were acquired from the Science Citation Index Expanded of the Web of Science Core Collection. Analysis of countries/regions, institutions, authors, co-cited references, and keywords were done using Citespace and VOSviewer software. RESULTS: The final analysis included 2215 documents contributed by 9091 scholars from 2053 institutions in 83 countries, with the United States being the largest contributor globally. Institutional and author collaboration analysis showed that collaborations are scattered and lack stable and intensive collaborative relationships. The journal 'Clinical and Experimental Rheumatology' was the most prolific journal. Anti-endothelial cell antibodies, interleukin-6, adalimumab, colour Doppler ultrasonography, and stents and prosthesis were the main research areas in TAK.Double-blind multicentre clinical trials, disease activity evaluation and cytokines were identified to be recent keyword bursts. CONCLUSIONS: Although the area of TAK research is growing rapidly, intensive institutional and author collaboration has to be fostered in the future to fuel TAK research and information dissemination. Future research on TAK may revolve around cytokines, disease activity evaluation and clinical trials.

A microRNA sponge, LINC02193, promotes neutrophil activation by upregulating ICAM1 and is correlated with ANCA-associated vasculitis.

OBJECTIVE: To investigate the pathogenic role and underlying mechanisms of lncRNAs in antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). METHODS：: RNA-sequencing (RNA-seq) was applied to screen the expression profile of lncRNAs in peripheral leukocytes from 5 AAV patients and 5 healthy controls (HC). Candidate lncRNAs were preliminarily verified in peripheral leukocytes from 46 AAV patients and 35 HC by qRT-PCR. Then, the identified LINC02193 was further validated in peripheral neutrophils from 67 AAV patients, 45 HC and 64 disease controls. Correlation between LINC02193 levels and disease activity was analyzed. Then, a loss-of-function study was conducted to investigate the role of LINC02193 in neutrophils activation. Furthermore, bioinformatics analysis, dual luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to explore the mechanism of LINC02193 regulating neutrophils activation. RESULTS: A total of 467 upregulated and 412 downregulated lncRNAs were identified in AAV patients. From top 5 upregulated lncRNAs, an elevation of LINC02193 was validated in a larger sample of AAV patients, and positively correlated with disease activity. Knockdown of LINC02193 inhibited ROS and NO production, NETs release and adhesion to endothelial cells of differentiated human promyelocytic leukaemia HL­60 cells (dHL-60), whereas overexpression of ICAM1 counteracted these effects. Mechanistic analysis demonstrated that LINC02193 acted as a miR-485-5p sponge to relieve the repressive effect of miR-485-5p on ICAM1, thus promoting ICAM1 expression. CONCLUSION: LINC02193, a novel lncRNA identified in AAV could function as competing endogenous RNAs (ceRNA) for miR-485-5p to promote ICAM1 expression and neutrophils activation, suggesting its potential as a therapeutic target of AAV.

The role of plateletcrit in Takayasu arteritis: A potential biomarker for disease activity and 6-month treatment response.

OBJECTIVES: To determine the role of plateletcrit as a potential biomarker for disease activity and treatment response in Takayasu arteritis (TAK). METHODS: Totally, 215 newly diagnosed TAK patients were consecutively enrolled. Demographic data, clinical manifestations, laboratory and imaging examinations, and treatment strategy were recorded at baseline and at each visit during the 6-month treatment period. Normal plateletcrit (0.1%-0.4%) and hyper-plateletcrit (>0.4%) observed at baseline were used as group criteria. RESULTS: At baseline, the overall plateletcrit was 0.32 (0.24-0.38)%, with a normal and high level observed in 172 (80.00%) and 43 (20.00%) patients, respectively. Baseline plateletcrit was significantly higher in patients with active disease and associated with inflammatory biomarkers, including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and interleukin (IL)-6 (all p < .01). At 6 months, complete remission was achieved in 171 (79.53%) patients, and a significant decrease in plateletcrit was observed in these cases (p < .01). Patients with a normal baseline plateletcrit were more likely to achieve complete remission compared to those with a high baseline plateletcrit (HR = 4.65, 95% CI: 2.38-19.08, p < .01). In addition, ESR (p = .01) and IL-6 (p = .02) levels were still higher in patients with a high baseline plateletcrit at 6 months. Progression of vascular lesions was indicated in 18 (8.37%) patients at 6 months, and these patients also had significantly higher baseline plateletcrit (p = .03). CONCLUSION: Plateletcrit levels were positively related to disease activity and inflammatory index in TAK. Importantly, patients with high baseline plateletcrit levels may show a worse treatment response at 6 months.

Exploration of molecular signatures associated with different clinical features of Takayasu arteritis based on a prospective cohort study.

Takayasu arteritis (TAK) is complicated disorder without reliable biomarkers. Here, we aimed to explore TAK-associated factor panels and their changes after biologic treatment. Five factor panels were identified: 1. systemic inflammation: C3, ESR, CRP, PLT, IL-6, C4, and IgG; 2. vascular inflammation: YKL40, IL-16, PTX3, and CCL2; 3. immune regulation panel: IL-10, IFN-γ, CCL5, and MMP1; 4. angiogenesis and fibrosis: FGF, PDGFAB, and VEGF; and 5. vascular remodeling: CD19+ B cell ratio, MMP3, and leptin. Panel 1 parameters were closely related to disease activity, while Panel 5 parameters, particularly CD19+ B cell ratio and leptin, were significantly higher in ischemic patients. After treatment, tocilizumab had a stronger inhibitory effect on Panel 1 parameters, PTX3, and YKL-40, while adalimumab led to an increase in IL-16, CCL2, and leptin levels. Altogether, these data expanded our knowledge regarding molecular background in TAK development and shed light on precise treatment in future studies.

Comparison of the efficacy and safety of leflunomide versus placebo combined with basic prednisone therapy in patients with active disease phase of Takayasu arteritis: study protocol for a randomized, double-blinded controlled trial (Takayasu arteritis clinical trial in China: TACTIC).

Background: Takayasu arteritis (TAK) is an immune-induced granulomatous vasculitis that occurs primarily in young Asian women. Our previous cohort studies have indicated that leflunomide (LEF), which can lead to rapid induction and might be a promising alternative treatment for TAK. Objectives: To compare the efficacy and safety of LEF versus placebo combined with prednisone for active TAK in a Chinese population. Design: This will be a multicenter, randomized, double-blinded controlled trial aiming to recruit 116 TAK patients with active disease. This study will last 52 weeks. Methods and analysis: Participants will be assigned randomly to the LEF intervention arm or placebo control arm at a 1:1 ratio. Initially, LEF combined with prednisone will be given to the intervention arm and a placebo tablet combined with prednisone will be given to the placebo arm. At the end of week 24, subjects who achieved clinical remission or partial clinical remission will proceed to maintenance therapy with LEF to the end of week 52; those who did not achieve clinical remission or partial clinical remission in the LEF intervention arm will drop out from the study, and those in the placebo control arm will switch to LEF treatment to week 52. The primary endpoint will be the clinical remission rate of LEF versus placebo at the end of week 24. The secondary endpoints will be the time to clinical remission, mean dose of prednisone, disease recurrence, time to recurrence, adverse events, as well as clinical remission in subjects who switched from the placebo control arm to LEF therapy after week 24. Intention to treat will be the primary analysis. Discussion: This is the first randomized double-blinded placebo-controlled trial to clarify the efficacy and safety of LEF in treating active TAK. The results will provide more evidence for TAK management. Registration: ClinicalTrials.gov identifier: NCT02981979.

A novel molecular mechanism of vascular fibrosis in Takayasu arteritis: macrophage-derived GPNMB promoting adventitial fibroblast extracellular matrix production in the aorta.

Takayasu arteritis (TAK) is a chronic large vessel disease characterized by aortic fibrotic thickening, which was mainly mediated by activation of aorta adventitial fibroblasts (AAFs). Our previous genetic study demonstrated that TAK-associated locus IL6 rs2069837 regulated glycoprotein non-metastatic melanoma protein B (GPNMB) expression. Thus, this study aimed to investigate the pathogenic role of GPNMB in TAK. Through pathological staining, we find that GPNMB was mainly expressed in vascular adventitia and positively correlated with adventitial extracellular matrix (ECM) expression in TAK vascular lesion. Specifically, GPNMB was increased in adventitial CD68+ macrophages, which were closely located with CD90+ adventitial fibroblasts. In in-vitro cell culture, THP-1-derived macrophages with GPNMB overexpression promoted ECM expression in AAFs. This effect was also confirmed in aortic tissue or AAFs culture with GPNMB overexpression or active GPNMB protein stimulation. Mechanistically, Co-IP assay and siRNA or inhibitor intervention demonstrated that integrin αVß1 receptor mediated GPNMB effect on AAFs, which also activated downstream Akt and Erk pathway in AAFs. Furthermore, we showed that leflunomide treatment inhibited GPNMB-mediated fibrosis in AAFs, as well as GPNMB expression in macrophages, which were also partially validated in leflunomide-treated patients. Taken together, these data indicated that macrophage-derived GPNMB promotes AAFs ECM expression via the integrin αVß1 receptor and Akt/Erk signaling pathway and leflunomide might play an anti-fibrotic role in TAK by interfering with the macrophage-derived GPNMB/AAFs axis. This study provides evidence that targeting GPNMB is a potential therapeutic strategy for treating vascular fibrosis in TAK.

Augmented PFKFB3-mediated glycolysis by interferon-γ promotes inflammatory M1 polarization through the JAK2/STAT1 pathway in local vascular inflammation in Takayasu arteritis.

BACKGROUND: Takayasu arteritis (TAK) is characterized by pro-inflammatory M1 macrophage infiltration and increased interferon (IFN)-γ expression in vascular lesions. IFN-γ is a key cytokine involved in M1 polarization. Macrophage polarization is accompanied by metabolic changes. However, the metabolic regulation mechanism of IFN-γ in M1 macrophage polarization in TAK remains unclear. METHODS: Immunohistochemistry and immunofluorescence were employed to observe the expression of IFN-γ, PFKFB3 (6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3, the rate-limiting enzyme in glycolysis), and macrophage surface markers in the vascular tissue. Monocyte-derived macrophages from patients with TAK were cultured to examine the role of PFKFB3 in IFN-γ-induced M1 macrophage polarization. Seahorse analysis was used to detect the alterations in glucose metabolism during this process. Quantitative reverse transcription PCR, flow cytometry, and western blot were used to confirm the phenotypes of macrophages and related signaling pathways. RESULTS: In the vascular adventitia of patients with TAK, an increase in PFKFB3 accompanied by IFN-γ expression was observed in M1 macrophages. In vitro, IFN-γ successfully induced macrophage differentiation into the M1 phenotype, which was manifested as an increase in CD80 and HLA-DR markers and the pro-inflammatory cytokines IL-6 and TNF-α. During this process, PFKFB3 expression and glycolysis levels were significantly increased. However, glycolysis and M1 polarization induced by IFN-γ were suppressed by a PFKFB3 inhibitor. In addition, JAK2/STAT1 phosphorylation was also enhanced in macrophages stimulated by IFN-γ. The effects of IFN-γ on macrophages, including the expression of PFKFB3, glycolysis, and M1 polarization, were also inhibited by the JAK inhibitor tofacitinib or STAT1 inhibitor fludarabine. CONCLUSION: PFKFB3-mediated glycolysis promotes IFN-γ-induced M1 polarization through the JAK2/STAT1 signaling pathway, indicating that PFKFB3 plays an important role in M1 polarization mediated by IFN-γ; thus, PFKFB3 is a potential intervention target in TAK.

Genetic association and single-cell transcriptome analyses reveal distinct features connecting autoimmunity with cancers.

Autoimmune diseases (ADs) are at a significantly higher risk of cancers with unclear mechanism. By searching GWAS catalog database and Medline, susceptible genes for five common ADs, including systemic lupus erythematosus (SLE), rheumatoid arthritis, Sjögren syndrome, systemic sclerosis, and idiopathic inflammatory myopathies, were collected and then were overlapped with cancer driver genes. Single-cell transcriptome analysis was performed in the comparation between SLE and related cancer. We identified 45 carcinogenic autoimmune disease risk (CAD) genes, which were mainly enriched in T cell signaling pathway and B cell signaling pathway. Integrated single-cell analysis revealed immune cell signaling was significantly downregulated in renal cancer compared with SLE, while stemness signature was significantly enriched in both renal cancer or lymphoma and SLE in specific subpopulations. Drugs targeting CAD genes were shared between ADs and cancer. Our study highlights the common and specific features between ADs and related cancers, and sheds light on a new discovery of treatments.

A comprehensive profile of chemokines in the peripheral blood and vascular tissue of patients with Takayasu arteritis.

BACKGROUND: Takayasu arteritis (TAK) is a chronic granulomatous large vessel vasculitis with multiple immune cells involved. Chemokines play critical roles in recruitment and activation of immune cells. This study aimed to investigate chemokine profile in the peripheral blood and vascular tissue of patients with TAK. METHODS: A total of 58 patients with TAK and 53 healthy controls were enrolled. Chemokine array assay was performed in five patients with TAK and three controls. Chemokines with higher levels were preliminarily validated in 20 patients and controls. The validated chemokines were further confirmed in another group of samples with 25 patients and 25 controls. Their expression and distribution were also examined in vascular tissue from 8 patients and 5 controls. Correlations between these chemokines and peripheral immune cells, cytokines, and disease activity parameters were analyzed. Their serum changes were also investigated in these 45 patients after glucocorticoids and immunosuppressive treatment. RESULTS: Patients and controls were age and sex-matched. Twelve higher chemokines and 4 lower chemokines were found based on the chemokine array. After validation, increase of 5 chemokines were confirmed in patients with TAK, including CCL22, RANTES, CXCL16, CXCL11, and IL-16. Their expressions were also increased in vascular tissue of patients with TAK. In addition, levels of RANTES and IL-16 were positively correlated with peripheral CD3+CD4+ T cell numbers. Close localization of CCL22, CXCL11, or IL-16 with inflammatory cells was also observed in TAK vascular tissue. No correlations were found between these chemokines and cytokines (IL-6, IL-17, IFN-γ) or inflammatory parameters (ESR, CRP). No differences were observed regarding with these chemokines between active and inactive patients. After treatment, increase of CCL22 and decrease of RANTES and CXCL16 were found, while no changes were showed in levels of CXCL11 and IL-16. CONCLUSIONS: CCL22, RANTES, CXCL16, CXCL11, and IL-16 were identified as the major chemokines involved in the recruitment of immune cells in the vascular tissue of patients with TAK. Additionally, the persistently high levels of CCL22, CXCL11, and IL-16 observed after treatment indicate their role in vascular chronic inflammation or fibrosis and demonstrate the need for developing more efficacious treatment options.

FABP3 overexpression promotes vascular fibrosis in Takayasu's arteritis by enhancing fatty acid oxidation in aorta adventitial fibroblasts.

OBJECTIVE: To identify the role of fatty acid binding protein 3 (FABP3) in vascular fibrosis in Takayasu's arteritis (TAK) and to explore the underlying molecular mechanism. METHODS: The expression of FABP3 and extracellular matrix proteins (ECMs) were detected in aorta tissues from TAK patients (n = 12) and healthy controls (n = 8) by immunohistochemistry. The concentration of serum proteins was determined by ELISA. CCK8 and Ki67 staining were used to measure aorta adventitial fibroblast (AAF) proliferation. Widely targeted lipidomic profiling was used to screen for associated metabolic pathways. Changes in ECMs and fatty acid oxidation (FAO)-related enzymes were determined by RT-qPCR and Western blot. The interactions between FABP3 and these enzymes were explored with a co-immunoprecipitation (Co-IP) assay. RESULTS: The expression of FABP3 was increased in the thickened adventitia of TAK patients and was positively correlated with the serum expression of ECMs. FABP3 knockdown inhibited AAF proliferation and ECM production, whereas FABP3 overexpression enhanced these processes. Further analysis revealed that FABP3 upregulation promoted carnitine palmitoyltransferase 1A and carnitine/acylcarnitine carrier protein (CACT) expression, two key enzymes in FAO, as well as adenosine triphosphate (ATP) levels. FABP3 and CACT were co-localized in the adventitia and bound to each other in AAFs. Etomoxir reversed the enhanced FAO, ATP production, AAF proliferation and ECM production mediated by FABP3 upregulation. Treatment with 60 g/day curcumin granules for 3 months reduced the level of serum FABP3. Curcumin also inhibited vascular fibrosis by reducing FABP3-enhanced FAO in AAFs. CONCLUSION: Elevated FABP3 expression accelerated vascular fibrosis in TAK, which was likely mediated by promoting FAO in AAFs.

Transcatheter Aortic Valve Replacement for Aortic Regurgitation Caused by Takayasu Arteritis.

Aortic regurgitation (AR) in patients with Takayasu arteritis is considered a relatively common clinical condition. Aortic valve replacement as a surgical treatment, however, is known to have a high risk of postoperative prosthetic valve detachment or anastomotic pseudoaneurysm. This pilot study reports on an initial experience with transcatheter aortic valve replacement (TAVR) for AR caused by Takayasu arteritis. The outcome suggests that TAVR may be a potentially feasible alternative treatment option for AR in Takayasu arteritis, especially in relatively older and vulnerable patients.

Potential Role of Macrophage Phenotypes and CCL2 in the Pathogenesis of Takayasu Arteritis.

Objectives: To investigate vascular macrophage phenotype as well as vascular and peripheral chemokine (C-C motif) ligand 2 (CCL2) expression during different stages of disease progression in patients with Takayasu Arteritis (TA). Methods: In this study, 74 patients with TA and 50 controls were recruited. TA disease activity was evaluated with Kerr scores. Macrophage phenotype and CCL2 expression were examined by immunohistochemistry in vascular specimens from 8 untreated and 7 treated TA patients, along with 4 healthy controls. Serum CCL2 were quantified by enzyme-linked immune-absorbent assay from TA patients at baseline (n=59), at 6-months (n=38), and from 46 healthy volunteers. Vascular macrophage phenotype, vascular CCL2 expression and serum CCL2 levels during different stages, as well as the relationship between serum CCL2 and disease activity or other inflammatory parameters (erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and interleukin 6 (IL-6)) were investigated. Results: In untreated patients, vascular M1 macrophages and CCL2 showed increased expression, mainly in the adventitia. In contrast, in treated patients, vascular adventitial M1 and CCL2 expression were decreased, while vascular medial M2 macrophages and CCL2 levels were increased. Distribution of macrophages and CCL2 was consistent within the TA vascular lesions regardless of the disease stage. Furthermore, peripheral CCL2 was elevated in patients with TA (TA: 160.30 ± 120.05 vs. Control: 65.58 ± 54.56 pg/ml, P < 0.001). CCL2 levels were found to correlate with ESR, CRP, and IL-6 (all R values between 0.55 and 0.6, all P < 0.001). Receiver operating curve analysis demonstrated that CCL2 (at the cut-off value of 100.36 pg/ml) was able to predict disease activity (area under the curve = 0.74, P = 0.03). Decrease in CCL2 level was observed in patients with clinical remission (CR), but not in patients without CR, after 6 months of treatment (CR patients: baseline 220.18 ± 222.69 vs. post-treatment 88.71 ± 55.89 pg/ml, P = 0.04; non-CR patients: baseline 142.45 ± 104.76 vs. post-treatment 279.49 ± 229.46 pg/ml, P = 0.02). Conclusions: Macrophages contribute to vascular pathological changes in TA by undergoing phenotype transformation. CCL2 is an important factor for recruiting macrophages and a potential biomarker for disease activity.

Potential risk of hyperuricemia: leading cardiomyocyte hypertrophy by inducing autophagy.

BACKGROUND: Clinical studies have shown that hyperuricemia is associated with many cardiovascular diseases; however, the mechanisms involved remain unclear. In this study, we investigated the effect of uric acid on cardiomyocytes and the underlying mechanism. METHODS AND RESULTS: H9c2 cardiomyocytes were treated with various concentrations of uric acid. 3-Methyladenine (3-MA) or Compound C was added before treatment with uric acid. The expression of myocardial hypertrophy-related genes was measured using polymerase chain reaction (PCR). The cell surface area was calculated using ImageJ Software. Western blotting was used to measure the protein levels. Uric acid increased the gene expression of Nppa, Nppb, and Myh5, which are involved in myocardial hypertrophy, and the relative cell surface area of cardiomyocytes in a dose-dependent manner. Consistently, the ratio of LC3II/I, which is a biomarker of autophagy, increased dose-dependently, whereas the protein level of p62, a protein that is degraded by autophagy, decreased. 3-MA, an autophagy inhibitor, rescued uric acid-induced myocardial hypertrophy. Treatment with uric acid increased the level of phosphorylated adenosine monophosphate kinase (AMPK), as well as its downstream effector unc-51-like kinase (ULK1). Pharmacological inhibition of AMPK by Compound C attenuated the uric acid-induced activation of autophagy and myocardial hypertrophy. CONCLUSIONS: Uric acid induces myocardial hypertrophy by activating autophagy via the AMPK-ULK1 signaling pathway. Decreasing the serum uric acid level may therefore be clinically beneficial in alleviating cardiac hypertrophy.

The value of interleukin-6 in predicting disease relapse for Takayasu arteritis during 2-year follow-up.

OBJECTIVE: To evaluate the value of interleukin-6 (IL-6) in predicting long-term disease prognosis for Takayasu arteritis (TA). METHODS: Sixty-seven TA patients, who had IL-6 levels detected at the first visit and had a regular follow-up of at least 2 years, were enrolled. Data recorded up to March 31, 2019, including clinical presentations, laboratory indices, treatments, and radiological images were collected and used for analysis. The value of IL-6 in predicting disease relapse and imaging progression was analyzed. RESULTS: IL-6 levels were positively related with disease activity index, including Kerr scores, C-reactive protein (CRP) levels. Patients were divided into three groups according to baseline serum IL-6 levels: low group (< 5.4 pg/mL, n = 29), medium group (5.4-11.5 pg/mL, n = 20), and high group (> 11.5 ng/mL, n = 18). Patients in the medium and high group had higher disease activity than those in the low group (p < 0.01). Baseline IL-6 levels were correlated with luminal stenosis (p < 0.05), although no significant correlations with long-term imaging progression were observed. Patients with more than 2 episodes of disease relapses were most commonly seen in the medium group (p < 0.05). Multivariate Cox proportional hazard regression analysis indicated that medium and high IL-6 levels were positive predictors for disease relapse (HR 4.3, 95%CI 1.3-18.7 p = 0.07 for medium group; HR 2.1, 95% CI 0.7-48.9, p = 0.19 for high group) with disease status and treatment adjusted. CONCLUSIONS: IL-6 may be a valuable predictor of TA disease relapse during long-term follow-up. Treatments targeted at IL-6 pathways might reduce disease relapse and have better prognostic effects for TA. Key Points • Positive relationships between IL-6 levels and disease activity index, including Kerr scores, C-reactive protein (CRP) levels, etc. were indicated. • Medium and high baseline IL-6 levels were valuable for predicting disease relapse during the 2-year follow-up. • Baseline IL-6 levels were positively correlated with luminal stenosis on imaging.

CYR61/TGF-ß axis promotes adventitial fibrosis of Takayasu's arteritis in the IL-17 mediated inflammatory microenvironment.

OBJECTIVES: Takayasu's arteritis (TAK) is characterised by inflammation and fibrosis in the aortas, but its pathogenesis remains unclear. The aim of the study is to demonstrate the role of cysteine-rich protein 61 (CYR61), a novel proinflammatory factor, in the inflammation and fibrosis of TAK vessels. METHODS: CYR61 expression in the aortic vessel was compared between TA tissues and healthy samples by immunohistochemistry staining. The effect of CYR61 on the proliferation, migration and activation of adventitial fibroblasts (AFs) in the IL-17-mediated inflammatory microenvironment was studied in vitro. RESULTS: Here we found higher expression of CYR61 in the aortic adventitia in TAK patients than in healthy donors by immunohistochemistry staining. In vitro, recombinant human CYR61 (rhCYR61) significantly upregulated the proliferation of primary human aortic adventitial fibroblasts (AFs) and their expression of extracellular matrix (ECM) proteins such as collagen I, collagen III and fibronectin at the mRNA and protein levels, but rhCYR61 partly inhibited the migration of AFs. The integrin αvß1 was identified as a membrane receptor of CYR61 in AFs, and its downstream Erk1/2 pathway was found activated by detecting its phosphorylation level. Pretreatment with PD98059, an inhibitor of Erk1/2, down-regulated the mRNA and protein expression of ECM proteins in the rhCYR61-stimulated AFs. Furthermore, rhCYR61 up-regulated the expression of TGF-ß, and TGF-ß siRNA transfection obviously attenuated the profibrotic effect ofrhCYR61. Finally, to clarify the cooperation between CYR61 and classical proinflammatory factors, IL-17 was chosen as a co-stimulator in the culture of AFs. rhIL-17 promoted the mRNA and protein expression of CYR61 in AFs, and the collaboration of rhIL-17 and rhCYR61 dramatically boosted the synthesis of ECM and TGF-ß. CONCLUSIONS: Our findings suggest that CYR61 played a profibrotic role through the TGF-ß pathway and it enhanced IL-17-mediated inflammation and fibrosis in the mechanism of vascular impairment in TAK.

The potential role of leflunomide in inhibiting vascular fibrosis by down-regulating type-II macrophages in Takayasu's arteritis.

OBJECTIVES: Inflammatory fibrosis of aortic lesions promoted by type II macrophages (M2) is one of the most serious incidents in Takayasu's arteritis (TAK), and the currently available therapies can not effectively block the inflammatory fibrosis. Here we explored whether leflunomide (LEF) could improve the fibrosis by down-regulating M2 in TAK. METHODS: Peripheral blood mono-nuclear cells (PBMCs) from 16 TAK patients were treated by leflunomide, and the ratio of M1/M2 macrophages and apoptosis of M2 were detected by flow cytometry. Supernatant levels of cytokines and chemokines secreted by M2 were measured by ELISAs. mRNA expression of profibrotic factors in M2 were analysed by real time PCR. Western blotting was used to analyse the activation of signal transducer activator of transcription (STAT)-6. RESULTS: LEF could inhibit M2 polarisation by curtailing STAT6 phosphorylation. LEF could also promote apoptosis of M2 and reduce the release of M2-derived CCL22 as well as the expression of profibrotic cytokines including CCL22 and TGF-ß in M2. CONCLUSIONS: LEF could potentially reduce vascular fibrosis by down-regulating the number and function of M2, which, eventually, could alleviate inflammatory fibrosis of aortic lesions in TAK patients.