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- Sumpter, N. A., et al.
(author)
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Association of Gout Polygenic Risk Score With Age at Disease Onset and Tophaceous Disease in European and Polynesian Men With Gout
- 2023
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In: Arthritis & Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 75:5, s. 816-825
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Journal article (peer-reviewed)abstract
- Objective. To determine whether a gout polygenic risk score (PRS) is associated with age at gout onset and tophaceous disease in European, East Polynesian, and West Polynesian men and women with gout. Methods. A 19-variant gout PRS was produced in 7 European gout cohorts (N = 4,016), 2 East Polynesian gout cohorts (N = 682), and 1 West Polynesian gout cohort (N = 490). Sex-stratified regression models were used to estimate the relationship between the PRS and age at gout onset and tophaceous disease. Results. The PRS was associated with earlier age at gout onset in men (beta = -3.61 in years per unit PRS [95% confidence interval (95% CI) -4.32, -2.90] in European men; beta = -6.35 [95% CI -8.91, -3.80] in East Polynesian men; beta = -3.51 [95% CI -5.46, -1.57] in West Polynesian men) but not in women (beta = 0.07 [95% CI -2.32, 2.45] in European women; beta = 0.20 [95% CI -7.21, 7.62] in East Polynesian women; beta -3.33 [95% CI -9.28, 2.62] in West Polynesian women). The PRS showed a positive association with tophaceous disease in men (odds ratio [OR] for the association 1.15 [95% CI 1.00, 1.31] in European men; OR 2.60 [95% CI 1.66, 4.06] in East Polynesian men; OR 1.53 [95% CI 1.07, 2.19] in West Polynesian men) but not in women (OR for the association 0.68 [95% CI 0.42, 1.10] in European women; OR 1.45 [95% CI 0.39, 5.36] in East Polynesian women). The PRS association with age at gout onset was robust to the removal of ABCG2 variants from the PRS in European and East Polynesian men (beta = -2.42 [95% CI -3.37, -1.46] and beta = -6.80 [95% CI -10.06, -3.55], respectively) but not in West Polynesian men (beta = -1.79 [95% CI -4.74, 1.16]). Conclusion. Genetic risk variants for gout also harbor risk for earlier age at gout onset and tophaceous disease in European and Polynesian men. Our findings suggest that earlier gout onset involves the accumulation of gout risk alleles in men but perhaps not in women, and that this genetic risk is shared across multiple ancestral groups.
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| 2. |
- Elsaid, K., et al.
(author)
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Amplification of Inflammation by Lubricin Deficiency Implicated in Incident, Erosive Gout Independent of Hyperuricemia
- 2023
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In: Arthritis & Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 75:5, s. 794-805
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Journal article (peer-reviewed)abstract
- Objective In gout, hyperuricemia promotes urate crystal deposition, which stimulates the NLRP3 inflammasome and interleukin-1 beta (IL-1 beta)-mediated arthritis. Incident gout without background hyperuricemia is rarely reported. To identify hyperuricemia-independent mechanisms driving gout incidence and progression, we characterized erosive urate crystalline inflammatory arthritis in a young female patient with normouricemia diagnosed as having sufficient and weighted classification criteria for gout according to the American College of Rheumatology (ACR)/EULAR gout classification criteria (the proband).Methods We conducted whole-genome sequencing, quantitative proteomics, whole-blood RNA-sequencing analysis using serum samples from the proband. We used a mouse model of IL-1 beta-induced knee synovitis to characterize proband candidate genes, biomarkers, and pathogenic mechanisms of gout.Results Lubricin level was attenuated in human proband serum and associated with elevated acute-phase reactants and inflammatory whole-blood transcripts and transcriptional pathways. The proband had predicted damaging gene variants of NLRP3 and of inter-alpha trypsin inhibitor heavy chain 3, an inhibitor of lubricin-degrading cathepsin G. Changes in the proband's serum protein interactome network supported enhanced lubricin degradation, with cathepsin G activity increased relative to its inhibitors, SERPINB6 and thrombospondin 1. Activation of Toll-like receptor 2 (TLR-2) suppressed levels of lubricin mRNA and lubricin release in cultured human synovial fibroblasts (P < 0.01). Lubricin blunted urate crystal precipitation and IL-1 beta induction of xanthine oxidase and urate in cultured macrophages (P < 0.001). In lubricin-deficient mice, injection of IL-1 beta in knees increased xanthine oxidase-positive synovial resident M1 macrophages (P < 0.05).Conclusion Our findings linked normouricemic erosive gout to attenuated lubricin, with impaired control of cathepsin G activity, compounded by deleterious NLRP3 variants. Lubricin suppressed monosodium urate crystallization and blunted IL-1 beta-induced increases in xanthine oxidase and urate in macrophages. The collective activities of articular lubricin that could limit incident and erosive gouty arthritis independently of hyperuricemia are subject to disruption by inflammation, activated cathepsin G, and synovial fibroblast TLR-2 signaling.
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