Uric Levels Research Articles

Serum urate levels and neurodegenerative outcomes: a prospective cohort study and mendelian randomization analysis of the UK Biobank

BackgroundPrevious studies on the associations between serum urate levels and neurodegenerative outcomes have yielded inconclusive results, and the causality remains unclear. This study aimed to investigate whether urate levels are associated with the risks of Alzheimer’s disease and related dementias (ADRD), Parkinson’s disease (PD), and neurodegenerative deaths.MethodsThis prospective study included 382,182 participants (45.7% men) from the UK Biobank cohort. Cox proportional hazards models were used to assess the associations between urate levels and risk of neurodegenerative outcomes. In the Mendelian randomization (MR) analysis, urate-related single-nucleotide polymorphisms were identified through a genome-wide association study. Both linear and non-linear MR approaches were utilized to investigate the potential causal associations.ResultsDuring a median follow-up period of 12 years, we documented 5,400 ADRD cases, 2,553 PD cases, and 1,531 neurodegenerative deaths. Observational data revealed that a higher urate level was associated with a decreased risk of ADRD (hazard ratio [HR]: 0.93, 95% confidence interval [CI]: 0.90, 0.96), PD (HR: 0.87, 95% CI: 0.82, 0.91), and neurodegenerative death (HR: 0.88, 95% CI: 0.83, 0.94). Negative linear associations between urate levels and neurodegenerative events were observed (all P-values for overall < 0.001 and all P-values for non-linearity > 0.05). However, MR analyses yielded no evidence of either linear or non-linear associations between genetically predicted urate levels and the risk of the aforementioned neurodegenerative events.ConclusionAlthough the prospective cohort study demonstrated that elevated urate levels were associated with a reduced risk of neurodegenerative outcomes, MR analyses found no evidence of causality.

Uric Acid Inhibits Mice Pancreatic Steatosis via the Glycerophospholipid Pathway.

Background: despite evidence for mutually reinforcing effects of serum uric acid (SUA) and lipids, the effects of uric levels on pancreatic steatosis are not well-established. In this study, the relationship between low concentrations of uric acid and pancreatic steatosis was evaluated. Methods: forty C57BL/6J mice were fed a diet of high uric acid (HU), high fat (HF), high uric acid and high fat (HUHF), and normal control (NC) (10 mice in each group). Weight was measured weekly. Ultrasonography was performed to observe the pancreatic echo intensity of all mice before the end of feeding. Subsequently, peripheral blood was taken for biochemical examination. Intact pancreatic tissues were taken, part of which was used for pathological examination, part of which was used for PCR experiments and Western Blot experiments to obtain glycerophospholipid-associated mRNA data and protein levels. Results: body weight was significantly higher in the HF group than in the other three groups. Higher uric acid matched lower total cholesterol and triglyceride, matched higher low-density lipoprotein, and matched equal high-density lipoprotein. Ultrasound images and HE staining of pancreatic tissues of mice showed that higher uric acid matched lower fat content. The mRNA levels of phospholipase A2 group IB were highest in high uric acid group, while relative protein expression levels were lowest in high uric acid and control groups. Phospholipase A2 group IIA showed the opposite patterns. Conclusions: elevated serum uric acid at low concentrations can inhibit pancreatic steatosis, which is modulated via the glycerophospholipid metabolic pathway.

Herbal remedies in the management of hyperuricemia and gout: A review of in vitro, in vivo and clinical evidences.

Gout, or hyperuricemia is a multifactorial and multi-faceted metabolic disease that is quite difficult to manage and/or treat. Conventional therapies such as non-steroidal anti-inflammatory drugs (NSAIDs) such as allopurinol, corticosteroids and colchicine amongst others, have helped in its management and treatment to some extent. This study aimed to compile and analyze the different herbal remedies used in the management of hyperuricemia and gout. A literature search was conducted from key databases (PubMed, ScienceDirect, Cochrane Library, Google Scholar) using relevant keywords via the PRISMA model. Smilax riparia A.DC. from Traditional Chinese Medicine is used in many countries for its therapeutic effect on lowering serum urate levels. No single study was able to establish the efficacy of a specific traditionally used herb via in vitro, in vivo, and clinical studies. Patients were found to use a panoply of natural remedies, mainly plants to treat hyperuricemia and gout, which have been validated to some extent by in vitro, in vivo, and clinical studies. Nonetheless, further research is needed to better understand the ethnopharmacological relationship of such herbal remedies.

P085 Implementing treat-to-target urate-lowering therapy during hospitalisations for gout flares: a prospective cohort study

Abstract Background/Aims Hospitalisations for gout flares have doubled in England during the last 15 years. Despite this, no studies have evaluated strategies designed to increase the uptake of urate-lowering therapy (ULT) in people hospitalised for gout flares. Methods We conducted a prospective cohort study in people hospitalised for gout flares. We designed and evaluated an intervention package that consisted of an optimal, in-hospital management pathway based upon BSR, EULAR and ACR guidelines, which encouraged ULT initiation prior to discharge, followed by a nurse-led, post-discharge review. Outcomes including: i) ULT initiation; ii) serum urate target attainment, and iii) re-hospitalisation rates were compared between patients hospitalised for flares in the 12 months post-implementation vs. a retrospective cohort of hospitalised patients from 12 months pre-implementation. Results 119 and 108 patients, respectively, were hospitalised for gout flares in the 12 months before and after the intervention was launched. For patients with six-month follow-up data available (n = 94 and n = 97, respectively), the proportion of patients who were newly initiated on ULT increased to 92% post-implementation, from 49% pre-implementation (age and sex-adjusted odds ratio (aOR) 11.5; 95% CI 4.36-30.5; p &amp;lt; 0.001). More patients achieved a serum urate ≤360 micromol/L within six months of discharge (27% post-implementation vs. 11% pre-implementation; aOR 3.04; 95% CI 1.36-6.78; p = 0.007). The proportion of patients who were re-hospitalised for flares was 9% post-implementation vs. 15% pre-implementation (aOR 0.53, 95% CI 0.22 to 1.32; p = 0.18). Conclusion Following implementation of a strategy designed to optimise care during gout hospitalisations, more than 90% of ULT-naïve patients were initiated on ULT - nearly double the pre-implementation baseline. Despite greater initiation of ULT in the acute flare setting, recurrent hospitalisations did not increase following implementation; supporting the use of ULT in this setting. Improvements were seen in urate target attainment post-discharge; however, focused approaches to optimise ULT dose escalation to achieve target urate levels are required. Disclosure M.D. Russell: Honoraria; AbbVie, Biogen, Eli Lilly, Galapagos, Menarini. Grants/research support; Eli Lilly, Janssen, Pfizer, UCB. L. Ameyaw-Kyeremeh: None. F. Dell'Accio: None. H. Lapham: None. N. Head: None. C. Stovin: None. V. Patel: None. B. Clarke: None. D. Nagra: None. E. Alveyn: None. M.A. Adas: None. K. Bechman: Grants/research support; Versus Arthritis/Pfizer. M.A. de la Puente: None. B. Ellis: None. C. Byrne: None. R. Patel: None. A.I. Rutherford: Other; Educational support from Eli Lilly, UCB. F. Cantle: None. S. Norton: None. E. Roddy: None. J. Hudson: None. A.P. Cope: Honoraria; BMS, AbbVie, GSK/Galvini. Grants/research support; BMS. J.B. Galloway: Honoraria; Abbvie, Biovitrum, BMS, Celgene, Chugai, Gilead, Janssen, Lilly, Novartis, Pfizer, Roche, Sanofi, Sobi, UCB.

Sex-Specific Differences in Cytokine Production Capacity in Patients with Gout Compared to Controls

Gout, an inflammatory disease orchestrated by interleukin-1β activation and release, is more prevalent in men. The clinical profiles of patients with gout report differences by sex. This study aims to investigate sex-specific cytokine profiles in circulation and in stimulated peripheral blood mononuclear cells (PBMCs) of patients with gout and controls. Participants included in the gout group met the criteria of the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR). The control group included individuals with varying levels of serum urate and absence of gout. PBMCs were stimulated in vitro for 24 h with various TLR ligands. Cytokines were determined in culture supernatants and plasma. Plasma IL-1Ra and high-sensitivity C-reactive protein (hsCRP) were higher in men with gout compared to men without gout whereas no significant differences in circulating cytokines were observed in women. PBMCs of patients with gout showed higher cytokine production of IL-1β, IL-1Ra, and TNF-α following 24 h stimulation, predominantly observed in women. We identified sex-specific cytokine production in gout in response to in vitro stimulation. While men with gout had higher levels of circulating cytokines, stimulated PBMCs of women with gout show an enhanced capacity for cytokine production. These data may suggest potentially different regulatory mechanisms of inflammation in men and women with gout.

Associations between hyperuricemia and ultrasound-detected knee synovial abnormalities in middle-aged and older population: a cross-sectional study

ObjectivesKnee synovial abnormalities, potentially treatment targets for knee pain and osteoarthritis, are common in middle-aged and older population, but its etiology remains unclear. We examined the associations between hyperuricemia and knee synovial abnormalities detected by ultrasound in a general population sample.MethodsParticipants aged ≥ 50 years were from a community-based observational study. Hyperuricemia was defined as serum urate (SU) level > 416 µmol/L in men and > 357 µmol/L in women. Ultrasound of both knees was performed to determine the presence of synovial abnormalities, i.e., synovial hypertrophy, effusion, or Power Doppler signal (PDS). We examined the relation of hyperuricemia to prevalence of knee synovial abnormalities and its laterality, and the dose-response relationships between SU levels and the prevalence of knee synovial abnormalities.ResultsIn total, 3,405 participants were included in the analysis. Hyperuricemia was associated with higher prevalence of knee synovial abnormality (adjusted odds ratio [aOR] = 1.21, 95% confidence interval [CI]: 1.02 to 1.43), synovial hypertrophy (aOR = 1.33, 95% CI: 1.05 to 1.68), and effusion (aOR = 1.21, 95% CI: 1.02 to 1.44), respectively. There were dose-response relationships between SU levels and synovial abnormalities. Additionally, the hyperuricemia was more associated with prevalence of bilateral than with that of unilateral knee synovial abnormality, synovial hypertrophy, or effusion; however, no significant association was observed between hyperuricemia and PDS.ConclusionIn this population-based study we found that hyperuricemia was associated with higher prevalence of knee synovial abnormality, synovial hypertrophy and effusion, suggesting that hyperuricemia may play a role in pathogenesis of knee synovial abnormalities.

Predictors of Inadequate Serum Urate Response to Low-Dose Febuxostat in Male Patients with Gout.

This study aimed to understand predictors of inadequate response (IR) to low-dose febuxostat treatment based on clinical variables. We pooled data from 340 patients of an observational cohort and two clinical trials who received febuxostat 20 mg/day for at least 3 months. IR was defined as failure to reach the target serum urate level (sUA<6 mg/dL) at any time point during 3 months treatment. The potential predictors associated with short- or mid-term febuxostat IR after pooling the three cohorts were explored using mixed-effect logistic analysis. Machine learning models were performed to evaluate the predictors for IR using the pooled data as the discovery set and validated in an external test set. Of the 340 patients, 68.9% and 51.8% were non-responders to low-dose febuxostat during short- and mid-term follow-up, respectively. Serum urate and triglyceride (TG) levels were significantly associated with febuxostat IR, but were also selected as significant features by LASSO analysis combined with age, BMI, and C-reactive protein (CRP). These five features in combination, using the best-performing stochastic gradient descent classifier, achieved an area under the receiver operating characteristic curve of 0.873 (95% CI [0.763, 0.942]) and 0.706 (95% CI [0.636, 0.727]) in the internal and external test sets, respectively, to predict febuxostat IR. Response to low-dose febuxostat is associated with early sUA improvement in individual patients, as well as patient age, BMI, and levels of TG and CRP.

THE EFFECT OF LEMON SKIN EXTRACT ON URIC ACID LEVELS OF HYPERURICEMIA MALE WISTAR RATS

Background: Uric acid is a metabolic process produced by each individual through the breakdown of purines carried out in the liver. Increased level of uric acid in blood is called hyperuricemia, which might cause gout if it is not treated properly. Lemon (Citrus Limon.) contains flavonoids which act as antioxidants and have the potential as antihyperuricemia Aim: This paper aimed to study the effect of lemon seed extract on uric acid levels Methods: Thirty-six male wistar rats from Farmhouse Ungaran were randomly divided into 6 groups, consists of healthy control group, hyperuricemic control, Allopurinol control, and treatment groups (3 groups). Hyperuricemia was induced by the administration of block broth and potassium oxonate for 4 weeks. Lemon seed extract doses of 17,5, 35, and 70 mg/kg BW, and Allopurinol 90 mg/kg BW was given orally for 2 weeks. Statistical analysis was conducted to evaluate differences among groups before and after the intervention. Results: There was a significant difference (p&lt;0,05) in uric acid levels before and after intervention of lemon peel extract in groups K1, K2, and P3. Meanwhile, in groups K0, P1, and P2, there were no significant differences. In the pre-test uric acid levels, there was a significant difference (p&lt;0,05) between the K0 group and K1, K2, P1, P2, and P3. Conclusion: There were no significant differences in the uric level acid of the treatment and control group after intervention, but there were significant differences in the effects of graded doses between the treatment groups.

Changes in Serum Urate Levels after Bariatric Surgery in Patients with Obesity: An Observational Study

BackgroundObesity is a risk factor for hyperuricemia and gout, while weight reduction can reduce urate levels. The aim of this study was to examine the effect of bariatric surgery on longitudinal serum urate levels.MethodsWe performed a retrospective observational study of 283 patients who had undergone bariatric surgery [237 (83.7%) gastric bypass, 34 (12.0%) sleeve gastrectomy and 12 (4.2%) gastric banding] and were followed up for 2 years. The results shown represent mean (standard deviation).ResultsBariatric surgery was associated with significant reduction in serum urate from baseline level of 0.343 (0.086) mmol/L to 0.296 (0.076) mmol/L (p < 0.001) at 12 months and 0.286 (0.073) mmol/L (p < 0.001) at 24 months, including in men and women, and in patients with or without diabetes. Patients with elevated urate levels at baseline, who comprised 27.2% of the total cohort, achieved reduction in levels by 4 months.ConclusionBariatric surgery leads to significant reduction in serum urate levels at 12 and 24 months. This could reduce incidence of gout and need for prophylactic medication(s).Graphical

Dotinurad restores exacerbated kidney dysfunction in hyperuricemic patients with chronic kidney disease.

In this study, we aimed to clarify the beneficial effects of urate-lowering treatment with the novel agent dotinurad on renal function in patients with chronic kidney disease (CKD) and hyperuricemia (HUA). Thirty-five patients with CKD (mean age 65.4 ± 14.8years, 23 men) diagnosed with HUA were recruited. Changes in eGFR before and after dotinurad administration were assessed. Patients first underwent a 3-month observation period and then 3months treatment with dotinurad. During the observation period, mean eGFR (mL/min/1.73 m2) declined significantly. The baseline eGFR was 31.8 ± 16.4 and the serum urate level (sUA, mg/dL) was 8.1 ± 1.7. During the treatment period, eGFR recovered to 36.5 ± 17.5 and sUA decreased to 6.7 ± 1.0. The increase in eGFR after dotinurad administration was correlated with a decrease in sUA (R = 0.375, p = 0.0263). Dotinurad administration to patients with CKD and HUA appears to be beneficial in restoring kidney function. Dotinurad may represent a potential medication for the prevention of kidney function decline caused by HUA.

Analysis of the Relationship of Serum Ferritin, Urate, and Some Hematological Parameters with Disease Activity in Gout Patients

Background and objectives: Gout is a type of arthritis. Acute gout is a common rheumatological disease that mostly affects first metatarsopharyngeal joint. Chronic gout is the condition that characterized by repeated episodes of acute gout. The objective of this study was to further explore the relationship between iron, ferritin, and other hematological markers with serum urate and gout. Methods: This cross sectional study was conducted in the Department of Rheumatology of Rizgary Teaching Hospital, Erbil, and Northern Iraqi Kurdistan. A total of 85 cases were enrolled in this study, 76 males and 9 females. There mean age (SD) was 46.6 (±11.2) years. All participants were known to have gout and fulfilled the criteria for diagnosis of gout. Serum ferritin, C-reactive protein, Serum iron, total iron binding capacity, and serum urate level were measured in addition to renal function tests and liver function tests were measured. Results: The mean (SD) for urate was 9.04 (±1.16) mg/dL, 76 (89.4%) patients with high serum uric acid had high level of ferritin in the blood meanwhile; 9 patients have normal ferritin level. There was a significant positive correlation (76 out of 85 patients) between serum ferritin level and serum urate (p&lt;0.005 and rho=0.237). A positive correlation was found between C reactive protein and urate level, in contrast there was no correlation of iron level and urate level. Conclusion: The ferritin and C reactive protein levels were significantly high among gouty patients.

Exploring the causal associations of micronutrients on urate levels and the risk of gout: A Mendelian randomization study

Growing evidence has indicated a potential association between micronutrient levels, urate levels, and the risk of gout. However, the causal association underlying these associations still remains uncertain. Previous observational studies and randomized controlled trials investigating the association between micronutrients, urate levels, and the risk of gout have been limited in their scope and depth. The aim of this study was to utilize Mendelian randomization (MR) to investigate the causal associations between genetically predicted micronutrient levels, urate levels, and the risk of gout. In this study, we conducted a comprehensive examination of 10 specific micronutrients (vitamin B6, vitamin B12, vitamin C, vitamin D, folate, calcium, iron, copper, zinc, and selenium) as potential exposures. Two-sample MR analyses were performed to explore their causal associations with urate levels and the risk of gout. In these analyses, gout data were collected from the Global Biobank Meta-Analysis Initiative (N=1,069,839, N cases=30,549) and urate levels data from CKDGen Consortium (N=288,649) by utilizing publicly available summary statistics from independent cohorts of European ancestry. We performed inverse-variance weighted MR analyses as main analyses, along with a range of sensitivity analyses, such as MR-Egger, weighted median, simple mode, weighted mode, Steiger filtering, MR-PRESSO, and Radial MR analysis, to ensure the robustness of our findings. The results of our study indicate that there were negative associations between serum vitamin B12 and urate levels, as well as serum folate and the risk of gout. Specifically, we found a negative association between vitamin B12 levels and urate levels, with a β coefficient of-0.324 (95% CI -0.0581 to-0.0066, P=0.0137) per one standard deviation (SD) increase. Similarly, a negative association was observed between folate levels and gout risk, with an odds ratio of 0.8044 (95% CI 0.6637 to 0.9750, P=0.0265) per one SD increase. On the other hand, we identified positive associations between serum calcium levels and both urate levels and the risk of gout. Specifically, there was a positive association between serum calcium levels and urate levels (β coefficient: 0.0994, 95% CI 0.0519 to 0.1468, P=4.11E-05) per one SD increase. Furthermore, a positive association was found between serum calcium levels and the risk of gout, with an odds ratio of 1.1479 (95% CI 1.0460 to 1.2598, P=0.0036) per one SD increase. These findings were robust in extensive sensitivity analyses. By employing MR-PRESSO and Radial MR to eliminate outliers, the observed associations have been reinforced. No clear associations were found between the other micronutrients and the urate levels, as well as the risk of gout. Our findings provided evidence that there were negative associations between serum vitamin B12 and urate levels, as well as serum folate and the risk of gout, while positive associations existed between the serum calcium levels and urate levels, as well as the risk of gout.

Health literacy and gout characteristics in a primary care cohort.

To examine the cross-sectional association between health literacy and gout characteristics. In a primary care cohort of adults living with gout, the prevalence of poor health literacy was defined using the Single-Item Literacy Screener (SILS). Multiple logistic regression was used to obtain adjusted odds ratios (ORs) for the cross-sectional associations between health literacy and individual gout characteristics (frequency of flares, age at gout onset, history of oligo-/polyarticular flares, allopurinol use, allopurinol dose and serum urate level) with 95% CIs and adjustment for age, sex, deprivation and further education. Of 551 participants [mean age 54.4 years (s.d. 11.2), 498 (90.4%) male], 163 (30.1%) reported two or more flares in the previous 12 months. Fifty-one (9.4%) had poor health literacy. Poor health literacy was associated with having two or more flares in the preceding 12 months [adjusted OR 4.10 (95% CI 2.04, 8.19)] and a history of oligo-/polyarticular flares [OR 1.93 (95% CI 1.06, 3.55)]. No associations were identified between health literacy and age at gout onset [OR 0.99 (95% CI 0.96, 1.01)], allopurinol use [OR 0.88 (95% CI 0.46, 1.65)] or dose [OR 1.00 OR (95% CI 1.00, 1.00)] or serum urate [most recent serum urate OR 1.0 (95% CI 1.00, 1.00)]. Frequent flares and a history of oligo-/polyarticular flares were associated with poor health literacy. Since health literacy is an important determinant of health outcomes, it is important to consider health literacy when providing information and education to people with gout.

Superiority of Low-Dose Benzbromarone Add-On to Low-Dose Febuxostat Compared With Febuxostat Monotherapy in Gout With Combined-Type Hyperuricemia.

There is an unmet need for simpler urate-lowering therapy (ULT) regimens that achieve the serum urate target and improve the overall quality of gout care. We report a comparative effectiveness trial of febuxostat monotherapy versus benzbromarone add-on to low-dose febuxostat in gout specifically with combined renal urate underexcretion and overload. A prospective randomized trial was conducted on patients with combined-type hyperuricemia and estimated glomerular filtration rate >60 mL/min/1.73 m2 1:1 randomly assigned to febuxostat and benzbromarone combination therapy (initially febuxostat at 20 mg/day, with benzbromarone at 25 mg/day added onto 20 mg/day of febuxostat if not at target) or febuxostat monotherapy (initially 20 mg/day, escalating to 40 mg/day if not at target). The primary end point at 12 weeks was the proportion achieving a serum urate (SU) level <360 μmol/L. Other outcomes included altered liver and kidney function, new-onset urolithiasis, and gout flares. There were 250 participants randomized; 219 completed 12-week treatment. More patients in the febuxostat and benzbromarone combination group achieved the SU target compared to patients in the febuxostat monotherapy group (75.5% vs 47.7%; odds ratio 3.37 [95% confidence interval 1.90-5.98]). Safety profiles were comparable between the two groups. Simply adding on low-dose benzbromarone (25 mg/day) to low-dose (20 mg/day) febuxostat showed superior urate lowering compared to febuxostat monotherapy in gout with a combined-type hyperuricemia. For selected patients, expedited achievement of the SU target in more than 75% of patients using one titration step and low xanthine oxidase inhibitor and uricosuric doses is a potential alternative to standard ULT regimens.

Serum urate is associated with an increased risk of inflammatory bowel disease: A bidirectional Mendelian randomization study.

Previous studies have indicated bidirectional associations between urate levels and inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD). However, it remains unclear whether the observations are causal because of confounding factors. To investigate the causal associations between urate levels and IBD using bidirectional Mendelian randomization (MR). Independent genetic variants for urate levels and IBD were selected as instrumental variables from published genome-wide association studies (GWASs). Summary statistics for instrument-outcome associations were retrieved from three separate databases for IBD (the UK Biobank, the FinnGen database and a large GWAS meta-analysis) and one for urate levels (a large GWAS meta-analysis). MR analyses included the inverse-variance-weighted method, weighted-median estimator, MR-Egger and sensitivity analyses (MR-PRESSO). A meta-analysis was also conducted to merge the data from separate outcome databases using a fixed-effects model. Genetically higher serum urate levels were strongly associated with an increased risk of UC [odds ratio (OR): 1.95, 95% confidence interval (CI): 1.86-2.05] after outlier correction, and the ORs (95%CIs) for IBD and CD were 0.94 (95%CI: 0.86-1.03) and 0.91 (95%CI: 0.80-1.04), respectively. Animal studies have confirmed the positive association between urate levels and UC. Moreover, genetically predicted IBD was inversely related to urate levels (OR: 0.97, 95%CI: 0.94-0.99). However, no association was observed between genetically influenced UC or CD and urate levels. Urate levels might be risk factors for UC, whereas genetically predicted IBD was inversely associated with urate levels. These findings provide essential new insight for treating and preventing IBD.

GWAS-identified hyperuricemia-associated IGF1R variant rs6598541 has a limited role in urate mediated inflammation in human mononuclear cells

Gout is a common autoinflammatory joint diseases characterized by deposition of monosodium urate (MSU) crystals which trigger an innate immune response mediated by inflammatory cytokines. IGF1R is one of the loci associated with both urate levels and gout susceptibility in GWAS to date, and IGF-1-IGF-1R signaling is implicated in urate control. We investigate the role of IGF-1/IGF1R signaling in the context of gouty inflammation. Also, we test the gout and urate-associated IGF1R rs6598541 polymorphism for association with the inflammatory capacity of mononuclear cells. For this, freshly isolated human peripheral blood mononuclear cells (PBMCs) were exposed to recombinant IGF-1 or anti-IGF1R neutralizing antibody in the presence or absence of solubilized urate, stimulated with LPS/MSU crystals. Also, the association of rs6598541 with IGF1R and protein expression and with ex vivo cytokine production levels after stimulation with gout specific stimuli was tested. Urate exposure was not associated with IGF1R expression in vitro or in vivo. Modulation of IGF1R did not alter urate-induced inflammation. Developing urate-induced trained immunity in vitro was not influenced in cells challenged with IGF-1 recombinant protein. Moreover, the IGF1R rs6598541 SNP was not associated with cytokine production. Our results indicate that urate-induced inflammatory priming is not regulated by IGF-1/IGF1R signaling in vitro. IGF1R rs6598541 status was not asociated with IGF1R expression or cytokine production in primary human PBMCs. This study suggests that the role of IGF1R in gout is tissue-specific and may be more relevant in the control of urate levels rather than in inflammatory signaling in gout.

Are gout patients with negative dual-energy computed tomography for monosodium urate crystal deposition easy to treat?

Abstract Objectives To determine the clinical associations and predictive value of two thresholds of negative dual-energy CT (DECT) for MSU crystal deposition in gout patients initiating urate-lowering therapy (ULT) and identify which threshold is more clinically relevant. Methods Patients from the CRYSTALILLE cohort with a diagnosis of gout naïve to ULT with baseline DECT scans of the knees and feet were selected. Two thresholds of positivity for DECT detection of MSU crystal deposition were considered (&amp;lt;0.01 cm3 and &amp;lt;0.1 cm3). Baseline characteristics and the prediction of key outcomes after ULT initiation, including reaching serum urate (SU) levels &amp;lt;6.0 and 5.0 mg/dl and occurrence of flares at 6, 12 and 24 months, associated with both thresholds of negative DECTs were compared with those of patients having positive DECT scans. Results A total of 211 patients, median age 66.2 years [interquartile range (IQR) 57–75.8], with a median symptom duration of 3 years (IQR 0–7.8) were included. A total of 38/211 (18%) and 90/211 (43%) had negative DECT scans for the 0.01 and 0.1 cm3 thresholds, respectively. Factors associated with negative DECT scans were younger age, shorter symptom duration and an absence of cardiovascular disease for both volume thresholds. A total of 9/39 (23.1%), 3/26 (11.5%) and 1/18 (5.6%) patients with &amp;lt;0.1 cm3 MSU crystals had flares at 6, 12 and 24 months, respectively, compared with 18/45 (40.0%), 9/36 (25.0%) and 2/18 (11.1%) patients with ≥0.1 cm3 (P &amp;gt; 0.05). Overall, 95 patients (68.3%) reached SU levels &amp;lt;6.0 mg/dl and 68 (48.9%) reached levels &amp;lt;5.0 mg/dl, without any difference between positive and negative DECTs, with ULT dosages that tended to be lower in patients with negative DECTs. Conclusion The 0.1 cm3 threshold was better correlated with clinical presentation and evolution than the 0.01 cm3 threshold. Gout patients with negative DECTs exhibit milder disease and a lower comorbidity burden. They do not exhibit particularly easy-to-treat hyperuricaemia but they may have a lower risk of flares.

Interaction of genetic variation at ADH1B and MLXIPL with alcohol consumption for elevated serum urate level and gout among people of European ethnicity

BackgroundAlcohol consumption is a risk factor for hyperuricaemia and gout. Multiple single-nucleotide polymorphisms (SNPs) have been identified as associated with both alcohol consumption and serum urate or gout in separate genome-wide association studies (GWAS). This study aimed to identify and characterise interactions between these shared signals of genetic association and alcohol consumption for serum urate level, hyperuricaemia, and gout.MethodsThis research was conducted using the UK Biobank resource. The association of alcohol consumption with serum urate and gout was tested among 458,405 European participants. Candidate SNPs were identified by comparing serum urate, gout, and alcohol consumption GWAS for shared signals of association. Multivariable-adjusted linear and logistic regression analyses were conducted with the inclusion of interaction terms to identify SNP-alcohol consumption interactions for association with serum urate level, hyperuricaemia, and gout. The nature of these interactions was characterised using genotype-stratified association analyses.ResultsAlcohol consumption was associated with elevated serum urate and gout. For serum urate level, non-additive interactions were identified between alcohol consumption and rs1229984 at the ADH1B locus (P = 3.0 × 10−44) and rs6460047 at the MLXIPL locus (P = 1.4 × 10−4). ADH1B also demonstrated interaction with alcohol consumption for hyperuricaemia (P = 7.9 × 10−13) and gout (P = 8.2 × 10−9). Beer intake had the most significant interaction with ADH1B for association with serum urate and gout among men, while wine intake had the most significant interaction among women. In the genotype-stratified association analyses, ADH1B and MLXIPL were associated with serum urate level and ADH1B was associated with hyperuricaemia and gout among consumers of alcohol but not non-consumers.ConclusionsIn this large study of European participants, novel interactions with alcohol consumption were identified at ADH1B and MLXIPL for association with serum urate level and at ADH1B for association with hyperuricaemia and gout. The association of ADH1B with serum urate and gout may occur through the modulation of alcohol metabolism rate among consumers of alcohol.

Serum Urate and Recurrent Gout

Approximately 12 million adults in the US have a history of gout, but whether serum urate levels can help predict recurrence is unclear. To assess associations of a single serum urate measurement with subsequent risk of acute gout flares and subsequent risk of hospitalizations for gout among patients in the UK with a history of gout. This retrospective study included patients with a history of gout identified from the UK between 2006 and 2010 who were followed up through Primary Care Linked Data medical record linkage until 2017 and through the Hospital Episode Statistics database until 2020. Serum urate levels at enrollment. Rate of recurrent acute gout, ascertained by hospitalization, outpatient, and prescription/procedure records, and adjusted rate ratios using negative binomial regressions. Among 3613 patients with gout (mean age, 60 years; 3104 [86%] men), 1773 gout flares occurred over a mean follow-up of 8.3 years. Of these, 1679 acute gout flares (95%) occurred in people with baseline serum urate greater than or equal to 6 mg/dL and 1731 (98%) occurred in people with baseline serum urate greater than or equal to 5 mg/dL. Rates of acute gout flares per 1000 person-years were 10.6 for participants with baseline urate levels less than 6 mg/dL, 40.1 for levels of 6.0 to 6.9 mg/dL, 82.0 for levels of 7.0 to 7.9 mg/dL, 101.3 for levels of 8.0 to 8.9 mg/dL, 125.3 for urate levels of 9.0 to 9.9 mg/dL, and 132.8 for levels greater than or equal to 10 mg/dL. Rate ratio of flares were 1.0, 3.37, 6.93, 8.67, 10.81, and 11.42, respectively, over 10 years (1.61 [1.54-1.68] per mg/dL). Rates of hospitalization per 1000 person-years during follow-up were 0.18 for those with baseline serum urate less than 6 mg/dL, 0.97 for serum urate of 6.0 to 6.9 mg/dL, 1.8 for serum urate of 7.0 to 7.9 mg/dL, 2.2 for serum urate of 8.0 to 8.9 mg/dL, 6.7 for serum urate of 9.0 to 9.9 mg/dL, and 9.7 for serum urate greater than or equal to 10 mg/dL. Rate ratios of hospitalization for gout, adjusting for age, sex, and race were 1.0, 4.70, 8.94, 10.37, 33.92, and 45.29, respectively (1.87 [1.57-2.23] per mg/dL). In this retrospective study of patients with a history of gout, serum urate levels at baseline were associated with the risk of subsequent gout flares and rates of hospitalization for recurrent gout. These findings support using a baseline serum urate level to assess risk of recurrent gout over nearly 10 years of follow-up.

Berberine alleviates chlorpyrifos-induced nephrotoxicity in rats via modulation of Nrf2/HO-1 axis

Chlorpyrifos (CPS), an organophosphorus insecticide, is widely used for agricultural and non-agricultural purposes with hazardous health effects. Berberine (BBR) is a traditional Chinese medicine and a phytochemical with anti-inflammatory and anti-oxidative properties. The present study evaluated the effects of BBR against kidney damage induced by CPS and the underlying mechanisms. An initial study indicated that BBR 50 mg/kg was optimal under our experimental conditions. Then, 24 rats (6/group) were randomized into: control, BBR (50 mg/kg/day), CPS (10 mg/kg/day), and CPS + BBR. BBR was administration 1 h prior to CPS. Each treatment was delivered daily for a period of 28 consecutive days using a gastric gavage tube. Compared to CPS-alone treated rats, BBR effectively improved renal function by preventing the rise in serum urea, creatinine, and uric levels. The reno-protective effects of BBR were confirmed through a histological examination of kidney tissues. BBR restored oxidant-antioxidant balance in renal tissues mediated by Keap1/Nrf2/HO-1 axis modulation. In addition, BBR decreased nitric oxide (NO) and myeloperoxidase (MPO) activity. This was paralleled with the potent down-regulation of NF-κB. Furthermore, BBR exhibited anti-apoptotic activities supported by the upregulation of Bcl-2 and down-regulation of Bax and caspase-3 expression. In conclusion, our data suggest that BBR attenuates CPS-induced nephrotoxicity in rats by restoring oxidant-antioxidant balance and inhibiting inflammatory response and apoptosis in renal tissue. This is mediated, at least partly, by modulation of the Nrf2/HO-1 axis.