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ObjectiveLinked metabolic and cardiovascular comorbidities are prevalent in hyperuricemia and gout. For mechanistic insight into impact on inflammatory processes and cardiometabolic risk factors of xanthine oxidase inhibitor urate-lowering therapy (ULT) titration to target, we performed a prospective study of gout serum metabolomes from a ULT trial.MethodsSera of gout patients meeting the 2015 ACR/EULAR gout classification criteria (n = 20) and with hyperuricemia were studied at time zero and weeks 12 and 24 of febuxostat or allopurinol dose titration ULT. Ultrahigh performance liquid chromatography-tandem mass spectroscopy acquired the serum spectra. Data were assessed using the Metabolon and Metaboloanalyst software. Lipolysis validation assays were done in febuxostat and/or colchicine-treated 3T3-L1 differentiated adipocytes.ResultsSerum urate decreased from time zero (8.21 ±1.139 SD) at weeks 12 (5.965 ± 1.734 SD) and 24 (5.655 ±1.763 SD). Top metabolites generated by changes in nucleotide and certain amino acid metabolism and polyamine pathways were enriched at 12 and 24 weeks ULT, respectively. Decreases in multiple fatty acid metabolites were observed at 24 weeks, linked with obesity. In cultured adipocytes, febuxostat significantly decreased while colchicine increased the lipolytic response to β-adrenergic-agonism or TNF.ConclusionMetabolomic profiles linked xanthine oxidase inhibitor-based ULT titration to target with reduced serum free fatty acids. In vitro validation studies revealed that febuxostat, but not colchicine, reduced lipolysis in cultured adipocytes. Since soluble urate, xanthine oxidase inhibitor treatment, and free fatty acids modulate inflammation, our findings suggest that by suppressing lipolysis, ULT could regulate inflammation in gout and comorbid metabolic and cardiovascular disease.

Objective: To assess whether circulating levels of adiponectin, leptin, and fibroblast growth factor 21 (FGF‐21) are associated with incident cardiovascular disease (CVD) in rheumatoid arthritis (RA). Methods: Adipokines were measured using banked enrollment serum from patients with RA and dichotomized above/below the median value. Incident CVD events (coronary artery disease [CAD], stroke, heart failure [HF] hospitalization, venous thromboembolism, CVD‐related deaths) were identified using administrative data and the National Death Index. Covariates were derived from medical record, biorepository, and registry databases. Multivariable Cox models were generated to quantify associations between adipokine concentrations and CVD incidence. Five‐year incidence rates were predicted. Results: Among 2,598 participants, 639 (25%) had at least 1 CVD event over 19,585 patient‐years of follow‐up. High adiponectin levels were independently associated with HF hospitalization (hazard ratio [HR] 1.39 [95% confidence interval (95% CI) 1.07–1.79], P = 0.01) and CVD‐related death (HR 1.49 [95% CI 1.16–1.92], P = 0.002) but not with other CVD events. High leptin was independently associated with CVD‐related death (HR 1.44 [95% CI 1.05–1.97], P = 0.02). High FGF‐21 levels were independently associated with lower rates of CAD (HR 0.75 [95% CI 0.58–0.97], P = 0.03). In subgroup analyses, associations between high adiponectin and leptin levels with CVD‐related death were driven by strong associations in nonobese patients. Conclusion: Adipokines are associated with HF hospitalization and CVD‐related death in patients with RA, with stronger associations in nonobese participants. These findings suggest that adipokines effectively predict clinically important outcomes in RA perhaps through an association with body composition and metabolic health. Further study is needed to determine whether adipokine measures might augment existing tools to identify RA patients at increased risk of CVD. [ABSTRACT FROM AUTHOR]

Objectives This study assessed whether circulating levels of adiponectin and leptin are associated with higher mortality in patients with RA. Methods Participants were adults from the Veterans Affairs RA Registry. Adipokines and inflammatory cytokines were measured as part of a multi-analyte panel on banked serum at enrolment. Dates and causes of death were derived from the Corporate Data Warehouse and the National Death Index. Covariates were derived from medical record, biorepository and registry databases. Multivariable Cox proportional hazard models evaluated associations between biomarkers and all-cause and cause-specific mortality. Results A total of 2583 participants were included. Higher adiponectin levels were associated with older age, male sex, white race, lower BMI, autoantibody seropositivity, radiographic damage, longer disease duration, prednisone use and osteoporosis. Higher adiponectin concentrations were also associated with higher levels of inflammatory cytokines but not higher disease activity at enrolment. Leptin was primarily associated with greater BMI and comorbidity. The highest quartile of adiponectin (vs lowest quartile) was associated with higher all-cause mortality [hazard ratio (HR): 1.46 (95% CI: 1.11, 1.93), P  = 0.009] and higher cardiovascular mortality [HR: 1.85 (95% CI: 1.24, 2.75), P  = 0.003], after accounting for covariates. Higher leptin levels were also associated with greater all-cause and cancer mortality. Conclusions Elevations in adipokines are associated with age, BMI, comorbidity and severe disease features in RA and independently predict early death. Associations between adiponectin and inflammatory cytokines support the hypothesis that chronic subclinical inflammation promotes metabolic changes that drive elevations in adipokines and yield adverse health outcomes. [ABSTRACT FROM AUTHOR]

Purpose: Rheumatoid arthritis (RA) is associated with a higher risk of diabetes mellitus (DM). Our aim was to determine associations between inflammatory disease activity (including evaluation of specific cytokines and chemokines) and incident DM.Methods: Participants were adults with physician-confirmed RA from Veteran's Affairs Rheumatoid Arthritis Registry. Disease activity and clinical assessments occur longitudinally as part of clinical care. Thirty cytokines and chemokines were measured in banked serum obtained at the time of enrolment. Cytokine/chemokine values were log-adjusted and standardised (per SD). Incident DM was defined based on validated algorithms using diagnostic codes and medications. Multivariable Cox proportional hazard models evaluated associations between clinical factors and incident DM. Independent associations between cytokines/chemokines and incident DM were assessed adjusting for age, sex, race, smoking, body mass index (BMI) and medication use at baseline.Results: Among 1866 patients with RA without prevalent DM at enrolment, there were 130 incident cases over 9223 person-years of follow-up. High Disease Activity Score (DAS28)-C reactive protein (CRP), obese BMI, older age and male sex were associated with greater risk for incident DM while current smoking and methotrexate use were protective. Patients using methotrexate were at lower risk. Several cytokines/chemokines evaluated were independently associated (per 1 SD) with DM incidence including interleukin(IL)-1, IL-6 and select macrophage-derived cytokines/chemokines (HR range 1.11-1.26). These associations were independent of the DAS28-CRP.Conclusions: Higher disease activity and elevated levels of cytokines/chemokines are associated with a higher risk of incident DM in patients with RA. Future study may help to determine if targeted treatments in at-risk individuals could prevent the development of DM. [ABSTRACT FROM AUTHOR]

The onset of alcoholic liver disease (ALD) is initiated by different cell types in the liver and a number of different factors including: products derived from ethanol-induced inflammation, ethanol metabolites, and the indirect reactions from those metabolites. Ethanol oxidation results in the production of metabolites that have been shown to bind and form protein adducts, and to increase inflammatory, fibrotic and cirrhotic responses. Lipopolysaccharide (LPS) has many deleterious effects and plays a significant role in a number of disease processes by increasing inflammatory cytokine release. In ALD, LPS is thought to be derived from a breakdown in the intestinal wall enabling LPS from resident gut bacterial cell walls to leak into the blood stream. The ability of adducts and LPS to independently stimulate the various cells of the liver provides for a two-hit mechanism by which various biological responses are induced and result in liver injury. Therefore, the purpose of this article is to evaluate the effects of a two-hit combination of ethanol metabolites and LPS on the cells of the liver to increase inflammation and fibrosis, and play a role in the development and/or progression of ALD.

Scavenger receptors on sinusoidal liver endothelial cells (SECs) eliminate potentially harmful modified proteins circulating through the liver. It was shown recently that aldehyde-modified proteins bind to scavenger receptors and are associated with the development/progression of alcoholic liver diseases. For these studies, rat livers were perfused in situ with 125I-formaldehyde-bovine serum albumin (f-Alb) or 125I-malondialdehyde-acetaldehyde-bovine serum albumin (MAA-Alb) in the presence of known scavenger receptor ligands as inhibitors. Reverse transcription-polymerase chain reaction (RT-PCR) analysis and scavenger receptor Type A (SRA) knock-out mice were used to assess the role of these receptors in mediating immune responses. The degradation of 125I-f-Alb or 125I-MAA-Alb in whole livers and isolated SECs can be inhibited by known scavenger receptor ligands, including f-Alb, maleylated bovine albumin, and fucoidan. 125I-f-Alb could not be completely inhibited by MAA-Alb. In contrast, 125I-MAA-Alb was only partially inhibited with advanced glycosylated endproduct albumin. RT-PCR data show the presence of a number of scavenger receptors on SECs that may be responsible for the binding of MAA-modified proteins. SRA seems to be one of these receptors involved in the effects mediated by MAA-modified proteins. In a study using SRA knockout mice, it was shown that a decreased antibody response to MAA-Alb resulted. By RT-PCR, CD36, LOX-1, and SR-AI are the scavenger receptors most likely involved in the degradation of MAA-Alb.