Contemporary Prevalence of Gout and Hyperuricemia in the United States and Decadal Trends: The National Health and Nutrition Examination Survey, 2007-2016

Association of Serum Uric Acid With All-Cause and Cardiovascular Mortality in Diabetes

OBJECTIVE

To investigate whether serum uric acid (SUA) level is associated with all-cause and cardiovascular disease (CVD) mortality among individuals with diabetes.

RESEARCH DESIGN AND METHODS

In this prospective cohort study, we included patients with diabetes from the U.S. National Health and Nutritional Examination Survey (NHANES) 1999-2018. Mortality and underlying causes of death were ascertained by linkage to national death records through 31 December 2019. Weighted Cox proportional hazards regression models were used to evaluate hazard ratios (HRs) and 95% CIs for all-cause and CVD mortality. We also performed a meta-analysis of available cohort studies to combine the association between SUA level and mortality in diabetes.

RESULTS

Among the 7,101 patients with diabetes from NHANES 1999-2018, the weighted mean of SUA level was 5.7 mg/dL. During 57,926 person-years of follow-up, 1,900 deaths (n = 674 deaths from CVD) occurred. In the fully adjusted model, when compared with patients with diabetes in the lowest SUA quintile, those in the highest SUA quintile had the HRs (95% CIs) of 1.28 (1.03, 1.58) for all-cause mortality and 1.41 (1.03, 1.94) for CVD mortality. We included 13 cohort studies in the meta-analysis and found that the pooled HRs (95% CIs) were 1.08 (1.05, 1.11) for all-cause mortality and 1.05 (1.03, 1.06) for CVD mortality per 1 mg/dL increment of SUA level in patients with diabetes.

CONCLUSIONS

This study indicated that higher SUA levels were associated with increased risks of all-cause and CVD mortality in diabetes. Interventional studies are needed to elucidate the health effect of treatments to lower SUA levels.

Increased Metallothionein-1 Associated with Gout Activity and Tophi

BACKGROUND AND AIMS

Gout is a chronic self-limiting inflammatory arthritis. An increase in metallothionein-1 (MT-1) has been reported in rheumatoid arthritis and osteoarthritis, and it attenuates inflammation and the pathology of diseases. This study aims to detect MT-1 levels in patients with gout and to explore its correlation with disease activity, clinical indexes, and inflammatory cytokines.

METHODS

The expression of MT-1 messenger RNAs (mRNAs) and protein levels in patients with gout were measured using real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Correlations between MT-1 and clinical indexes or inflammatory mediators were analyzed using Spearman's correlation test.

RESULTS

Compared with healthy controls (HCs, n = 43), patients with active gout (n = 27) showed higher levels of MT-1 mRNA in peripheral blood mononuclear cells and protein in serum, particularly those with tophi. No significant difference in serum MT-1 levels was observed among patients with inactive gout, HCs, and patients with hyperuricemia without gout. Furthermore, no significant difference was observed between patients with gout with kidney damage and HCs. In addition, serum interleukin (IL)-1β, IL-6, and IL-8 levels were significantly increased in patients with active gout, particularly in those with tophi. The serum MT-1 level was positively correlated with C-reactive protein, as well as with IL-1β, IL-6, and IL-18.

CONCLUSION

The higher levels of MT-1 were found in patients with gout, which were correlated with disease activity and gout related pro-inflammatory cytokines. Indicating MT-1 may serve as a new marker for predicting disease activity.Abbreviations: IL-1β: Interleukin 1β; MT-1: Metallothionein-1; CRP: C-Reactive Protein; ROS: Reactive Oxygen Species; IL-10: Interleukin 10; TGF-β: Transforming Growth Factor Beta.

Genetic Risk, Adherence to a Healthy Lifestyle, and Hyperuricemia: The TCLSIH Cohort Study

BACKGROUND

Genetic factors have been associated with hyperuricemia in large studies, but the extent to which this can be offset by a healthy lifestyle is unknown. This study aimed to examine whether healthy lifestyle could reduce hyperuricemia risk among individuals with different genetic profiles.

METHODS

We defined a lifestyle score using body mass index, smoking, alcohol consumption, physical activities, and diets in 2796 unrelated individuals from the Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) cohort study. Polygenic risk scores (PRS) were constructed based on uric acid loci. Associations of combined lifestyle factors and genetic risk and incident hyperuricemia were estimated using Cox proportional hazard regression.

RESULTS

Of 2796 individuals, 747 participants (26.7%) developed hyperuricemia. Genetic risk and lifestyle were predictors of incident events, and they showed an interaction for the outcome. Compared with high PRS, low PRS reduced risk of incident hyperuricemia by 40%, and compared with unhealthy lifestyle, healthy lifestyle reduced risk of incident hyperuricemia by 41%. Compared with unhealthy lifestyle and high genetic risk, adherence to healthy lifestyle was associated with a 68% (95% confidence interval, 44%-81%) lower risk of hyperuricemia among those at a low genetic risk.

CONCLUSIONS

In this prospective cohort study, we observed an interaction between genetics and lifestyle and the risk of hyperuricemia. The public health implication is that a healthy lifestyle is important for hyperuricemia prevention, especially for individuals with high genetic risk scores.

Global status and trends in gout research from 2012 to 2021: a bibliometric and visual analysis

BACKGROUND

Gout is the most common inflammatory arthritis with an increasing prevalence and incidence across the globe. We aimed to provide a comprehensive and systematic knowledge map of gout research to determine its current status and trends over the past decade.

METHODS

Publications on gout research were obtained from the Web of Science Core Collection (WOSCC) database. Bibliometric R, VOSviewer, and Citespace were employed to analyze the eligible literature.

RESULTS

A total of 5535 publications concerning gout research between 2012 and 2021 were included. Most publications and citations both numerically came from China. The strongest international cooperation belonged to the USA. The University of Auckland was the most productive institution with a leading place in research collaboration. The prime funding agency was the National Natural Science Foundation of China. Most papers were published in Clinical Rheumatology. Annals of the Rheumatic Diseases achieved the highest number of citations, H-index and IF, which showed the most excellent comprehensive strength. The individual author with the most paper authorship was Dalbeth Nicola with 241 publications and 46 H-index. Keywords and co-citation analysis discovered that pathological mechanism remains the future hotspot in gout research. It may involve gout connection with gut microbiota, NLRP3 inflammasome, xanthine oxidase, and urate-transporter ABCG2. In addition, besides metabolic diseases, the relationship between gout and heart failure may need more attention.

CONCLUSION

This study clarified the current status and research frontier in gout over the past decade, which would provide valuable research references for later researchers. Key Points •We disclosed the current status and frontier directions of gout over the past 10 years worldwide. •We identified future hotspots of gout research, including gout connection with gut microbiota, NLRP3 inflammasome, xanthine oxidase, and urate-transporter ABCG2. •We discovered that the relationship between gout and heart status would be the research frontier.

Gout: from Hippocrates till the modern time

Gout (podagra) is one of the most ancient articular diseases. Its accurate mechanisms and causes were delineated only during the last century. Major historical investigatory steps are described in relation to causality and pathogenesis of the disease from Hippocrates ages till the modern time. The newest genetic and epidemiologic aspects of the disease are presented in this article.

Association between Serum Uric Acid and Liver Enzymes in Adults Aged 20 Years and Older in the United States: NHANES 2005-2012

Although the relationship between serum uric acid (SUA) and nonalcoholic fatty liver disease has been widely reported, the relationship between SUA and liver enzymes has rarely been reported. The purpose of this study was to evaluate the association of SUA levels with alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in populations aged 20 years and older in the United States. We analyzed 7165 individuals aged 20 years and older from the National Health and Nutrition Examination Survey (NHANES) in the United States. Weighted multiple linear regression models were used to analyze the relationship between SUA and ALT and AST. A generalized additive model and a smooth curve fitting were used to observe the linear relationship. SUA was positively correlated with ALT and AST. In addition, the overall increasing trend of ALT and SUA was observed across the SUA quartile groups. In the stratified analysis by sex and race, the SUA levels in male, female, Mexican American, and Non-Hispanic White individuals, and those of another race, were positively correlated with ALT and AST. However, the SUA levels in Non-Hispanic Black individuals had a nonlinear relationship with ALT and AST. In individuals aged 20 years and older in the United States (excluding Non-Hispanic Black individuals), SUA levels were positively associated with ALT and AST. Therefore, with a rise in SUA levels, liver function should be monitored or intervened with in people aged 20 years and older in the United States.

The Effects of Curcumin on Inflammasome: Latest Update

Curcumin, a traditional Chinese medicine extracted from natural plant rhizomes, has become a candidate drug for the treatment of different diseases due to its anti-inflammatory, anticancer, antioxidant, and antibacterial activities. Curcumin is generally beneficial to improve human health with anti-inflammatory and antioxidative properties as well as antitumor and immunoregulatory properties. Inflammasomes are NLR family, pyrin domain-containing 3 (NLRP3) proteins that are activated in response to a variety of stress signals and that promote the proteolytic conversion of pro-interleukin-1β and pro-interleukin-18 into active forms, which are central mediators of the inflammatory response; inflammasomes can also induce pyroptosis, a type of cell death. The NLRP3 protein is involved in a variety of inflammatory pathologies, including neurological and autoimmune disorders, lung diseases, atherosclerosis, myocardial infarction, and many others. Different functional foods may have preventive and therapeutic effects in a wide range of pathologies in which inflammasome proteins are activated. In this review, we have focused on curcumin and evidenced its therapeutic potential in inflammatory diseases such as neurodegenerative diseases, respiratory diseases, and arthritis by acting on the inflammasome.

Anti-Hyperuricemic, Nephroprotective, and Gut Microbiota Regulative Effects of Separated Hydrolysate of α-Lactalbumin on Potassium Oxonate- and Hypoxanthine-Induced Hyperuricemic Mice

SCOPE

This study aims to investigate the anti-hyperuricemic and nephroprotective effects and the potential mechanisms of the separated gastrointestinal hydrolysates of α-lactalbumin on hyperuricemic mice.

METHODS AND RESULTS

The gastrointestinal hydrolysate of α-lactalbumin, the hydrolysate fraction with molecular weight (MW) < 3 kDa (LH-3k), and the fragments with smallest MW among LH-3K harvested through dextran gel chromatography (F5) are used. Hyperuricemia mice are induced via daily oral gavage of potassium oxonate and hypoxanthine. F5 displays the highest in vitro xanthine oxidase (XO) inhibition among all the fractions separated from LH-3k. Oral administration of F5 significantly reduces the levels of serum uric acid (UA), creatinine, and urea nitrogen. F5 treatment could ameliorate kidney injury through alleviating oxidative stress and inflammation. F5 alleviates hyperuricemia in mice by inhibiting hepatic XO activity and regulating the expression of renal urate transporters. Gut microbiota analysis illustrates that F5 administration increases the abundance of some SCFAs producers, and inhibits the growth of hyperuricemia and inflammation associated genera. LH-3k exhibits similar effects but does not show significance as those of the F5 fraction.

CONCLUSION

The anti-hyperuricemia and nephroprotective functions of F5 are mediated by inhibiting hepatic XO activity, ameliorating oxidative stress and inflammation, regulating renal urate transporters, and modulating the gut microbiota in hyperuricemic mice.

Wuling San Based on Network Pharmacology and in vivo Evidence Against Hyperuricemia via Improving Oxidative Stress and Inhibiting Inflammation

Background

Hyperuricemia (HUA) is a major public health issue with a high prevalence worldwide. Wuling San (WLS) is an effective treatment for HUA. However, the active compounds and the related mechanism are unclear. In this study, we aimed to explore the active compounds and the underlying pharmacological mechanisms of WLS against HUA.

Methods

First, a network pharmacology approach was used to detect active compounds of WLS, and potential targets and signaling pathways involved in the treatment of HUA were predicted. Then, a molecular docking strategy was used to predict the affinity between active compounds and key targets. Finally, to verify the prediction, the HUA rat model was established.

Results

49 active compounds with 108 common targets were obtained. Besides, cerevisterol, luteolin, ergosterol peroxide, beta-sitosterol, and sitosterol were identified as key active compounds. In PPI analysis, TNF, IL6, CASP3, PPARG, STAT3, and other 12 core targets were obtained. GO enrichment analysis indicated that WLS was likely to interfere with oxidative stress in the treatment of HUA, and KEGG enrichment analysis indicated multiple inflammation-related signaling pathways possibly involved in the treatment of HUA by WLS, including TNF, and NOD-like receptor, HIF-1, PI3K-Akt, and IL-17 signaling pathways. The results of molecular docking indicated that the active compounds had good binding properties to their key targets. In the validation experiments, WLS significantly reduced the levels of serum uric acid (SUA) and serum malondialdehyde (MDA). Moreover, WLS not only significantly increased the levels of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD), but also inhibited the expression of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6).

Conclusion

In the present study, we demonstrate that WLS has multicomponent, multitarget, and multi-pathway properties in the treatment of HUA. Its potential capability to reduce SUA could be ascribed to oxidative stress improvement and inflammation inhibition.

Interaction of Harmful Alcohol Use and Tea Consumption on Hyperuricemia Among Han Residents Aged 30-79 in Chongqing, China

Objective

The prevalence of hyperuricemia appears to be high worldwide. We aimed to explore the interaction between harmful alcohol use and tea consumption on hyperuricemia.

Methods

This study recruited 22,449 Han residents based on the data from the China Multi-Ethnic Cohort (CMEC) study, Chongqing province, to have a face-to-face electronic questionnaire, physical examination, and clinical laboratory tests. The difference in hyperuricemia between the different populations was compared by the Chi-square test. The interaction between harmful alcohol use and tea consumption was analyzed by the multivariate logistic regression model.

Results

Amongst 22,449 participants, the mean age was 51.5±11.8 years, and 46.83% of them were males. The proportion of harmful alcohol use, tea consumption, and harmful alcohol use and tea consumption were 14.01%, 21.01%, and 6.54%, respectively. Multivariate logistic regression showed that the odds ratio (OR) of harmful alcohol use and tea consumption (OR=2.21, 95% CI: 1.58-3.10) was greater than that of harmful alcohol use (OR=1.63, 95% CI:1.17-2.27) and tea consumption (OR=1.34, 95% CI:1.10-1.63). Among males, the results were similar (harmful alcohol use and tea consumption: OR=2.02, 95% CI: 1.43-2.84; harmful alcohol use: OR=1.61, 95% CI: 1.14-2.27; tea consumption: OR=1.28, 95% CI: 1.05-1.57). However, among females, the odds ratio of harmful alcohol use and tea consumption (OR=15.50, 95% CI: 1.36-176.50) was more than 10 times than that of only harmful alcohol use (OR=1.55, 95% CI: 0.42-5.69) or tea consumption (OR=1.22, 95% CI: 0.52-2.82).

Conclusion

The interaction of harmful alcohol use and tea consumption was a positive risk for hyperuricemia in Han residents aged 30-79 years in China.

Tophaceous gout in a young man with Gitelman syndrome: a case report with an overview

Gitelman syndrome represents the clinical manifestations of inactivation of the Slc12a3 genes encoding the thiazide-sensitive sodium chloride cotransporter and the Trpm6-Mg genes encoding the magnesium transporters in the distal convoluted tubule. In fact, the biochemical findings resemble those with thiazide diuretics such as hypokalemia, hypomagnesaemia, hypocalciuria, metabolic alkalosis, and low normal blood pressure. He is usually associated with calcium pyrophosphate deposition. Serum uricemia level is rarely affected in Gitelman syndrome. We aimed to report a rare association of chronic gout with Gitelman syndrome, hence the interest of our case. We describe a 29-year-old male patient with a history of Gitelman syndrome associated with articular gout including pelvic localization. We provided pictorial evidence of extensive and diffuse monosodium urate deposition in articular and periarticular structures to confirm the gout origin. A literature review illustrates 4 reported cases of Gitelman syndrome associated with gout. The gender distribution was equal with a mean age of 40 years.

Exposure to ambient particulate matter and hyperuricemia: An eight-year prospective cohort study on male traffic officers in China

BACKGROUND AND OBJECTIVES

Studies on the effects of airborne particulates of diameter ≤ 1 µm (PM₁), airborne particulates of diameter ≤ 2.5 µm (PM_2.5) and airborne particulates of diameter ranges from 1 to 2.5 µm (PM_1-2.5) on incidence of hyperuricemia are limited. We aimed to investigate the associations between PM₁, PM_2.5, and PM_1-2.5 and hyperuricemia among male traffic officers.

METHODS

We conducted a prospective cohort study of 1460 traffic officers without hyperuricemia in Guangzhou, China from 2009 to 2016. Exposures of PM₁ and PM_2.5 were estimated with a spatiotemporal model. PM_1-2.5 concentrations were calculated by subtracting PM₁ from PM_2.5 concentrations. Cox's proportional hazards regressions models were used to examine the association between PM₁, PM_2.5, and PM_1-2.5 and hyperuricemia, adjusted for potential confounders. Associations between PM₁, PM_2.5, and PM_1-2.5 and serum uric acid (SUA) levels were evaluated with multiple linear regression models.

RESULTS

Hazard ratios (HRs) and 95% confidence intervals (CIs) of hyperuricemia associated with 10 μg/m³ increment in PM₁, PM_2.5, and PM_1-2.5 were 1.67 (95% CI:1.30-2.36), 1.49 (95% CI: 1.27-1.75), and 2.18 (95% CI: 1.58-3.02), respectively. The SUA concentrations increased by 12.23 μmol/L (95% CI: 5.91-18.56), 6.93 μmol/L (95% CI: 3.02-10.84), and 8.72 μmol/L (95% CI: 0.76-16.68) per 10 μg/m³ increase in PM₁, PM_2.5, and PM_1-2.5, respectively. Stratified analyses indicated the positive associations of PM_2.5 and PM_1-2.5 with SUA levels were stronger in non-smokers, and PM₁, PM_2.5, and PM_1-2.5 with SUA levels were stronger in non-drinkers.

CONCLUSION

Long-term PM₁, PM_2.5, and PM_1-2.5 exposures may increase the risk of hyperuricemia and elevate SUA levels among male traffic officers, especially in non-smokers and non-drinkers.

Gout and Excess Risk of Severe SARS-CoV-2 Infection Among Vaccinated Individuals: A General Population Study

OBJECTIVE

Gout patients often have multiple comorbidities, making them susceptible to SARS-CoV-2 infection and poor outcomes. This study was undertaken to examine the association between gout and the risk of SARS-CoV-2 infection and severe outcomes, especially in patients who have received a SARS-CoV-2 vaccine.

METHODS

We conducted 2 cohort studies using The Health Improvement Network in the UK. Individuals with gout and those without gout from the general population were followed up from December 8, 2020 to October 31, 2021. We estimated the rate difference (RD) and hazard ratio (HR) of SARS-CoV-2 infection and severe outcomes (i.e., hospitalization and death within 30 days after SARS-CoV-2 infection) for individuals with gout versus those without gout using a Cox proportional hazards model according to SARS-CoV-2 vaccination status. We adjusted for potential confounders by using overlap weighting of exposure scores.

RESULTS

Among the vaccinated cohort, 1,955 cases of breakthrough COVID-19 infection occurred in 54,576 individuals with gout (4.68 cases per 1,000 person-months), and 52,468 cases occurred in 1,336,377 individuals without gout (3.76 cases per 1,000 person-months). The partially adjusted RD of breakthrough infection was 0.91 cases per 1,000 person-months (95% confidence interval [95% CI] 0.62-1.20 cases per 1,000 person-months), and the partially adjusted HR was 1.24 (95% CI 1.19-1.30). Gout was also associated with an increased risk of hospitalization (adjusted HR 1.30 [95% CI 1.10-1.53]) and death (adjusted HR 1.36 [95% CI 0.87-2.13]). Women with gout had an increased risk of hospitalization (adjusted HR 1.55 [95% CI 1.15-2.10]) and death (adjusted HR 2.46 [95% CI 1.12-5.41]). Similar associations with gout were observed in the unvaccinated cohort.

CONCLUSION

These general population data suggest that individuals with gout, especially women, have higher risks of SARS-CoV-2 infection and severe outcomes, even when vaccinated.

Triglyceride-Glucose Index is Significantly Associated with the Risk of Hyperuricemia in Patients with Nonalcoholic Fatty Liver Disease

Purpose

The triglyceride-glucose (TyG) index is a new index of insulin resistance (IR), and its association with hyperuricemia (HUA) is unclear. The aim of this study was to investigate whether TyG is an independent risk factor for hyperuricemia (HUA) in patients with nonalcoholic fatty liver disease (NAFLD).

Patients and Methods

We retrospectively analyzed 461 patients with ultrasound-confirmed NAFLD and calculated the TyG index. Multivariate logistic regression was used to analyze the relationship between the TyG index and HUA in NAFLD patients. The correlation between the TyG index and HUA was further confirmed by a restricted cubic spline. Furthermore, the stability of the association between TyG index and HUA was examined using subgroup analysis. Receiver operating characteristic (ROC) curves were constructed to evaluate the predictive value of the TyG index on HUA. Multivariate linear regression was used to analyze the linear relationship between the TyG index and serum uric acid.

Results

A total of 166 HUA patients and 295 non-HUA patients were included in the study. The results of multivariate logistic regression analysis showed that after controlling the confounding risk factors, TyG was still an independent risk factor for HUA (OR = 2.00, 95% CI: 1.38 -2.91, p < 0.001). Restricted cubic splines showed that HUA risk increased linearly with TyG across the entire TyG range. The ROC curve showed that TyG index was better than triglyceride in predicting HUA in NAFLD patients, with AUC values of 0.62 and 0.59, respectively. Multiple linear regression analysis showed that TyG index was significantly positively correlated with blood uric acid (B = 1.37, 95% CI: 0.67-2.08, p < 0.001).

Conclusion

TyG index is an independent risk factor for HUA in patients with NAFLD. The increase of the TyG index level is closely related to the occurrence and development of HUA in patients with NAFLD.

Trends in risk factor control in patients with gout: data from the National Health and Nutrition Examination Survey, 2007-2018

OBJECTIVES

To explore trends in risk factor control (hypertension, diabetes mellitus, hyperlipidaemia) in patients with gout and medication use among those whose risk factor control targets were not achieved.

METHODS

We used the data from National Health and Nutrition Examination Survey (NHANES) between 2007-2008 and 2017-2018 for analyses. The study samples were weighted so that they could be representative of the non-institutionalized US population. We conducted a cross-sectional analysis to assess trends in risk factor control and medication use, and employed logistic regression analyses to explore patient characteristics associated with risk factor control.

RESULTS

The prevalence of participants in whom blood pressure control target was achieved decreased from 64.6% in 2007-2008 to 55.3% in 2017-2018 (P-value for trend = 0.03). The percentage of participants whose glycaemic, lipid or all three risk factor control targets were achieved remained stable temporally (P > 0.05). Some patient characteristics were significantly related to risk factor control, including age 45-64, age ≥65, Asian Americans, non-Hispanic Blacks, higher family income, and being overweight and obese. A trend towards increased use of glucose-lowering medication was found (from 71.0% in 2007-2008 to 94.7% in 2017-2018, P < 0.01), while the prevalence of taking blood pressure-lowering and lipid-lowering medications remained stable (P > 0.05).

CONCLUSION

Based on NHANES data, a significant trend towards decreased blood pressure control was observed in patients with gout, while glycaemic and lipid control levelled off. These findings emphasize that more endeavours are needed to improve management of cardiovascular risk factors in patients with gout.

Single-cell RNA sequencing of immune cells in patients with acute gout

Cell subpopulations in the blood and joint fluid of patients with gout are poorly understood. Single-cell RNA sequencing and bioinformatic tools were used to identify cell subsets and their gene signatures in blood and synovial fluid (SF) cells, determine their relationships, characterize the diversity, and evaluate interactions among specific cell types. We identified 34 subpopulations (5 types of B cells, 16 types of T and natural killer cells, 9 types of monocytes, and 4 other cell types) in the blood of five healthy subjects and seven patients with acute gouty, and the SF of three patients with acute gout. We found that naïve CD4 T cells and classical monocytes cell populations were enriched in patients with gout, whereas plasmacytoid dendritic cells and intermediate monocytes were more abundant in healthy subjects. SF was enriched in Th1/Th17 cells, effector memory CD8 T cells, mucosal-associated invariant T cells, and macrophages. Subclusters of these cell subpopulations showed different compositions between healthy subjects and those with acute gout, according to blood and SF samples. At the cellular level, the inflammation score of a subpopulation or subcluster was highest in SF, following by the blood of acute gout patients and healthy person, whereas energy score showed the opposite trend. We also detected specific cell-cell interactions for interleukin-1, tumor necrosis factor-α, and transforming growth factor-β1 expression in the cells of patients with acute gout. Our study reveals cellular and molecular insights on inflammatory responses to hyperuricemia or uric crystal and may provide therapeutic guidance to improve treatments for gout.

High-density lipoprotein cholesterol modifies the association between blood lead and uric acid: results from NHANES 2005-2016

BACKGROUND

The association between blood lead (PbB) and uric acid (SUA) remains unclear in US adults without a high level of lead exposure. Additionally, the effects of high-density lipoprotein cholesterol (HDL-C) modifying this association are still unclear. Therefore, this study aims to assess the effect of modification of high-density lipoprotein cholesterol on the association between PbB and SUA.

METHOD

This research analyzed National Health and Nutrition Examination Survey (NHANES) data from 2005 to 2016. Through several screenings, 18,578 participants over the age of 20 were eligible for the analysis. Multivariable linear regression was used to evaluate the association between PbB and SUA. By having stratified participants based on the HDL-C intake category (low HDL-C intake < 50 mg/dl; high HDL-C intake ≥ 50 mg/dl), effect modification by HDL-C was assessed through a likelihood ratio test between PbB and SUA.

RESULT

Multivariable linear regression indicated that PbB positively affects SUA (β = 0.19, 95% CI 0.16-0.22). The relationship between PbB and SUA was different in the low and high HDL-C intake group (β 0.12 95% Cl 0.08-0.16 vs. β 0.26 95% Cl 0.22 ~ - 0.30). Furthermore, high-density lipoprotein cholesterol significantly modified the relationship between PbB and SUA in all models which indicates that the interaction of lead exposure and HDL-C is more dangerous than the sum of the individual effects.

CONCLUSIONS

Our study shows that high-density lipoprotein cholesterol and blood lead have an interactive effect on increasing uric acid, which may have great importance for clinical medication.

Folic Acid Protects against Hyperuricemia in C57BL/6J Mice via Ameliorating Gut-Kidney Axis Dysfunction

Emerging lines of research evidence point to a vital role of gut-kidney axis in the development of hyperuricemia (HUA), which has been identified as an increasing burden worldwide due to the high prevalence. The involved crosstalk which links the metabolic and immune-related pathways is mainly responsible for maintaining the axial homeostasis of uric acid (UA) metabolism. Nowadays, the urate-lowering drugs only aim to treat acute gouty arthritis as a result of their controversial clinical application in HUA. In this study, we established the HUA model of C57BL/6J mice to evaluate the effectiveness of folic acid on UA metabolism and further explored the underlying mechanisms. Folic acid attenuated the kidney tissue injury and excretion dysfunction, as well as the typical fibrosis in HUA mice. Molecular docking results also revealed the structure-activity relationship of the folic acid metabolic unit and the UA transporters GLUT9 and URAT1, implying the potential interaction. Also, folic acid alleviated HUA-induced Th17/Treg imbalance and intestinal tissue damage and inhibited the active state of the TLR4/NF-κB signaling pathway, which is closely associated with the circulating LPS level caused by the impaired intestinal permeability. Furthermore, the changes of intestinal microecology induced by HUA were restored by folic acid, including the alteration in the structure and species composition of the gut microbiome community, and metabolite short-chain fatty acids. Collectively, this study revealed that folic acid intervention exerted improving effects on HUA by ameliorating gut-kidney axis dysfunction.

Computer-assisted in vitro reconstitution of purine degradation pathway to lower the purine content in food

BACKGROUND

With the increasing prevalence of gout and its etiological hyperuricemia, dietary control of gout based on low-purine food according to patients' eating habits is becoming a better choice compared to the existing drug treatment such as allopurinol with notorious side effects. Reconstructing the purine metabolic pathway in vitro to degrade purine substances in food into natural functional allantoin appears to be an innovative method for preparing nutritious and healthy food of low purine content. The present study reports a computer-assisted in vitro reconstruction of four purinolytic enzymes metabolizing adenosine into allantoin to reduce purine content in food for personalized dietary control of hyperuricemia and gout.

RESULTS

Under the optimum reaction conditions of 40 °C and pH 7, 0.1 U of enzymes and 0.5 mmol L^-1 adenosine determined by an orthogonal test design, 16 different enzyme complexes were experimentally tested. The tested enzyme composition and allantoin production values were used as input and output to build a three-layer back propagation artificial neural network (BP-ANN) model, which was further optimized by a genetic algorithm (GA). The optimum enzyme complex predicted by the GA-BP-ANN model produced 248.08±7.832 μmol L^-1 allantoin, which was 19.9% higher than equimolar mixture of enzymes, and also more efficiently lowered purine contents in beer, as well as beef and yeast extracts.

CONCLUSION

This is the first in vitro reconstitution of complete purine metabolic pathway by combining ANN and GA technologies, with successful application with respect to lowering the purine content in food, indicating a promising application of computer-assisted in vitro reconstitution of purinolytic pathway in low-purine food to prevent hyperuricemia and gout. © 2022 Society of Chemical Industry.

Asymptomatic Hyperuricemia Is Associated with Achilles Tendon Rupture through Disrupting the Normal Functions of Tendon Stem/Progenitor Cells

Hyperuricemia is a metabolic disorder that is essential to the development of inflammatory gout, with increasing prevalence over recent years. Emerging clinical findings has evidenced remarkable tendon damage in individuals with longstanding asymptomatic hyperuricemia, yet the impact of hyperuricemia on tendon homeostasis and associated repercussions is largely unknown. Here, we investigated whether asymptomatic hyperuricemia was associated with spontaneous ruptures in the Achilles tendon and the pathological effect of hyperuricemia on the tendon stem/progenitor cells (TSPCs). Significantly higher serum uric acid (SUA) levels were found in 648 closed Achilles tendon rupture (ATR) patients comparing to those in 12559 healthy volunteers. In vitro study demonstrated that uric acid (UA) dose dependently reduced rat Achilles TSPC viability, decreased the expressions of tendon collagens, and deformed their structural organization while significantly increased the transcript levels of matrix degradative enzymes and proinflammatory factors. Consistently, marked disruptions in Achilles tendon tissue structural and functional integrity were found in a rat model of hyperuricemia, together with enhanced immune cell infiltration. Transcriptome analysis revealed a significant elevation in genes involved in metabolic stress and tissue degeneration in TSPCs challenged by hyperuricemia. Specifically, reduced activity of the AKT-mTOR pathway with enhanced autophagic signaling was confirmed. Our findings indicate that asymptomatic hyperuricemia may be a predisposition of ATR by impeding the normal functions of TSPCs. This information may provide theoretical and experimental basis for exploring the early prevention and care of ATR.

High Prevalence of Hyperuricemia and Associated Factors among Zhuang Adults: A Cross-Sectional Study Based on the Ethnic Minority Population Cohort in the Southwestern China

The highest prevalence of hyperuricemia was found in Zhuang minority adults in two national surveys in China, with only 1% Zhuang study subjects. However, the prevalence of hyperuricemia and the associated factors in Zhuang adults have not been well-addressed. A cross-sectional study was conducted to explore the prevalence of hyperuricemia and the common comorbidities, and the associated factors in Zhuang adults based on the Guangxi Ethnic Minority Population Cohort. Among 11,175 Zhuang adults aged 35-74 years, the age- and sex-standardized prevalence rate was 18.1% for hyperuricemia and 1.1% for gout. The standardized prevalence rate and awareness rate were 31.6% and 32.3%, respectively, for hypertension, and were 5.1% and 48.2%, respectively, for diabetes. High education level, history of coronary heart disease (CHD), hypertension, being a current drinker, high body mass index (BMI), central obesity, hyper-triglyceride (hyper-TG), hyper-total cholesterol (hyper-TC), hypo-high density lipoprotein cholesterol (hypo-HDL-C), and abnormal aspartate aminotransferase (AST) were risk factors, while smoking and diabetes were protective factors of hyperuricemia in males. Older age, being single/divorced, having a high education level, hypertension, drinking tea, high BMI, central obesity, hyper-TG, hyper-TC, hypo-HDL-C, and abnormal alanine aminotransferase (ALT) were risk factors in females. The high prevalence of hyperuricemia but low prevalence of gout and common comorbidities in Zhuang adults may be due to a lag effect of lifestyle changes. Health education and health management should be strengthened to prevent the progression of comorbidities, considering the lag effect and low awareness rate.

New insight into the management of renal excretion and hyperuricemia: Potential therapeutic strategies with natural bioactive compounds

Hyperuricemia is the result of increased production and/or underexcretion of uric acid. Hyperuricemia has been epidemiologically associated with multiple comorbidities, including metabolic syndrome, gout with long-term systemic inflammation, chronic kidney disease, urolithiasis, cardiovascular disease, hypertension, rheumatoid arthritis, dyslipidemia, diabetes/insulin resistance and increased oxidative stress. Dysregulation of xanthine oxidoreductase (XOD), the enzyme that catalyzes uric acid biosynthesis primarily in the liver, and urate transporters that reabsorb urate in the renal proximal tubules (URAT1, GLUT9, OAT4 and OAT10) and secrete urate (ABCG2, OAT1, OAT3, NPT1, and NPT4) in the renal tubules and intestine, is a major cause of hyperuricemia, along with variations in the genes encoding these proteins. The first-line therapeutic drugs used to lower serum uric acid levels include XOD inhibitors that limit uric acid biosynthesis and uricosurics that decrease urate reabsorption in the renal proximal tubules and increase urate excretion into the urine and intestine via urate transporters. However, long-term use of high doses of these drugs induces acute kidney disease, chronic kidney disease and liver toxicity. Therefore, there is an urgent need for new nephroprotective drugs with improved safety profiles and tolerance. The current systematic review summarizes the characteristics of major urate transporters, the mechanisms underlying the pathogenesis of hyperuricemia, and the regulation of uric acid biosynthesis and transport. Most importantly, this review highlights the potential mechanisms of action of some naturally occurring bioactive compounds with antihyperuricemic and nephroprotective potential isolated from various medicinal plants.

Prevalence and influence of hypouricemia on cardiovascular diseases in patients with rheumatoid arthritis

BACKGROUND

Serum uric acid (SUA) acts as an antioxidant and abnormally low SUA may raise the risk of developing atherosclerotic disorders. There is a U-shaped association between SUA with cardiovascular diseases (CVDs) in general population. However, the prevalence of hypouricemia and its influence on CVDs in rheumatoid arthritis (RA) remains unclear.

METHODS

This cross-sectional study collected clinical data from a Chinese RA cohort. Hypouricemia was defined as SUA ≤ 3.0 mg/dL, and hyperuricemia was defined as SUA ≥ 7.0 mg/dL. CVDs were defined as a history of angina pectoris, myocardial infarction, heart failure, stroke and peripheral arterial disease. Restricted cubic spline regression and logistic regression analysis were conducted to evaluate the associations between SUA levels and CVDs.

RESULTS

Among 1130 RA patients recruited, the mean age was 53.2 years and 79.0% were female. The prevalence of hypouricemia and hyperuricemia were 10.6% and 12.0%, respectively. RA patients with hyperuricemia had a higher rate of CVDs than normouricemic patients (27.9% vs. 7.1%, P < 0.05). Surprisingly, RA patients with hypouricemia also had a higher rate of CVDs (20.7% vs. 7.1%, P < 0.05) even without higher traditional cardiovascular risk factors. A U-shaped association between SUA levels and total CVDs was found (P_non-linear < 0.001). Multivariate logistic regression analysis revealed that compared with normouricemia, both hypouricemia [adjusted OR (AOR) = 4.707, 95% CI 2.570-8.620] and hyperuricemia (AOR = 3.707, 95% CI 2.174-6.321) were associated with higher risk of CVDs.

CONCLUSIONS

Hypouricemia may be a potential risk factor of CVDs in RA patients.

Higher dietary acid load is associated with hyperuricemia in Chinese adults: a case-control study

BACKGROUND

This study aims to explore the association between dietary acid load and hyperuricemia in Chinese adults.

METHODS

A case-control study was conducted. Adult participants with hyperuricemia were recruited as the cases and those without hyperuricemia were as the controls. Food consumption was evaluated by food frequency questionnaire (FFQ). Dietary acid load was assessed by potential renal acid load (PRAL) and net endogenous acid production (NEAP). Dietary acid load was divided into four levels: the first quartile (Q1), the second quartile (Q2), the third quartile (Q3) and the fourth quartile (Q4). Logistic regression model was applied for exploring the association between dietary acid load (PRAL and NEAP) and hyperuricemia. Odds ratio (OR) and its correspondence confidence interval (CI) were computed.

RESULTS

A total of 290 participants were eligible in this study, in which there were 143 individuals in case group and 147 in control group. A higher level of PRAL was found to be associated with odds of hyperuricemia. ORs of hyperuricemia for Q2, Q3 and Q4 of PRAL were 2.74 (95%CI: 1.94 ~ 3.88, p-value: 0.004), 2.90 (95%CI: 2.05 ~ 4.10, p-value: 0.002) and 3.14 (95%CI: 2.22 ~ 4.45, p-value: 0.001), respectively. There was a positive association between elevated NEAP and hyperuricemia. OR of hyperuricemia for Q2 was not material significance (OR:1.54, 95%CI: 0.93 ~ 2.53, p-value: 0.210), however, ORs of hyperuricemia for Q3 (OR: 2.40, 95%CI: 1.70 ~ 3.38, p-value: 0.011) and Q4 (OR: 3.27, 95%CI: 2.31 ~ 4.62, p-value: 0.001) were statistically significant.

CONCLUSION

Higher level of dietary acid load was found to be associated with hyperuricemia in Chinese adults, indicative of advocation of a well-balanced diet in this population.

Protein phosphatase 2A regulates xanthine oxidase-derived ROS production in macrophages and influx of inflammatory monocytes in a murine gout model

Background: Gout is a common arthritis, due to deposition of monosodium urate (MSU) crystals which results in IL-1β secretion by tissue-resident macrophages. Xanthine oxidase (XO) catalyzes uric acid (UA) production and in the process, reactive oxygen species (ROS) are generated which contributes to NLRP3 inflammasome activation. Protein phosphatase 2A (PP2A) may be involved in regulating inflammatory pathways in macrophages. The objective of this study was to investigate whether PP2A regulates gout inflammation, mediated by XO activity modulation. We studied UA and ROS generations in MSU stimulated murine bone marrow derived macrophages (BMDMs) in response to fingolimod phosphate, a PP2A activator, and compared its anti-inflammatory efficacy to that of an XO inhibitor, febuxostat. Methods: BMDMs were stimulated with MSU, GM-CSF/IL-1β or nigericin ± fingolimod (2.5 μM) or febuxostat (200 μM) and UA levels, ROS, XO, and PP2A activities, Xdh (XO) expression and secreted IL-1β levels were determined. PP2A activity and IL-1β in MSU stimulated BMDMs ± N-acetylcysteine (NAC) (10 μM) ± okadaic acid (a PP2A inhibitor) were also determined. M1 polarization of BMDMs in response to MSU ± fingolimod treatment was assessed by a combination of iNOS expression and multiplex cytokine assay. The in vivo efficacy of fingolimod was assessed in a murine peritoneal model of acute gout where peritoneal lavages were studied for pro-inflammatory classical monocytes (CMs), anti-inflammatory nonclassical monocytes (NCMs) and neutrophils by flow cytometry and IL-1β by ELISA. Results: Fingolimod reduced intracellular and secreted UA levels (p < 0.05), Xdh expression (p < 0.001), XO activity (p < 0.001), ROS generation (p < 0.0001) and IL-1β secretion (p < 0.0001), whereas febuxostat enhanced PP2A activity (p < 0.05). NAC treatment enhanced PP2A activity and reduced XO activity and PP2A restoration mediated NAC's efficacy as co-treatment with okadaic acid increased IL-1β secretion (p < 0.05). Nigericin activated caspase-1 and reduced PP2A activity (p < 0.001) and fingolimod reduced caspase-1 activity in BMDMs (p < 0.001). Fingolimod reduced iNOS expression (p < 0.0001) and secretion of IL-6 and TNF-α (p < 0.05). Fingolimod reduced CMs (p < 0.0001), neutrophil (p < 0.001) and IL-1β (p < 0.05) lavage levels while increasing NCMs (p < 0.001). Conclusion: Macrophage PP2A is inactivated in acute gout by ROS and a PP2A activator exhibited a broad anti-inflammatory effect in acute gout in vitro and in vivo.

Adherence to DASH Dietary Pattern and Its Association with Incident Hyperuricemia Risk: A Prospective Study in Chinese Community Residents

Hyperuricemia represents a great burden on global public health, and it is important to provide effective guidance at the level of dietary patterns. We evaluated the association between the Dietary Approaches to Stop Hypertension (DASH) diet and the risk of hyperuricemia in a large-scale, community-based cohort in East China. In total, 45,853 participants that did not have either hyperuricemia nor gout were included and assigned a DASH dietary score based on their baseline dietary intake. They were then divided into five quintiles (Q1−Q5) according to their score, followed by cross-linkages with local health information systems and in-person surveys. Cox proportional hazards models were adopted to calculate hazard ratio (HR) and 95% confidence intervals (CIs). During a median follow-up of 4.54 years, 2079 newly diagnosed hyperuricemia cases were documented. Compared to the DASH Q1 group, the risk of incident hyperuricemia for the Q5 group was significantly reduced by 16% (HR: 0.84; 95% CIs: 0.72−0.97) in the adjusted model. The associations of DASH diet with hyperuricemia appeared stronger (P for interaction <0.001) among participants with 3−4 cardiometabolic diseases at baseline, compared with their counterparts. Our results suggest that the DASH diet could be taken into account in the recognition of risk population and the prevention of hyperuricemia.

Palpable tophi and more comorbidities associated with adherence to urate-lowering medical therapy in a Chinese gout cohort

OBJECTIVE

Urate-lowering therapy (ULT) nonadherence is common and problematic in gout. Since, sociocultural factors affect adherence, we analyzed a Chinese cohort.

METHODS

We studied 903 Chinese gout patients aged 46.4±14.7 years (mean±SD), uniquely extending to assay of 2-year medication possession ratio (MPR) ≥80% defined as high adherence. Multivariable logistic regression analyses evaluated factors linked with adherence and ULT target attainment.

RESULTS

Characterization of ULT outcomes in this cohort revealed that after 2 years ULT, MPR ≥80% patients had better target serum urate (SU) achievement (from 23.3% to 71.0%, P <0.001), lower flare frequency and palpable tophi compared to MPR <80%. However, only 44.7% of cohort subjects had MPR ≥80%. Male sex (OR 3.68), gout onset age >60 years (OR 3.51), disease duration >5 years (OR 1.70), more comorbidities (OR 1.74), baseline palpable tophi (OR 1.53), SU <6mg/dL (360μmol/L) (OR 1.92) and more frequent follow-up visits (OR 1.98) were significantly associated with high adherence. Nevertheless, significant independent risk factors for failed SU target achievement included male sex (OR 0.36) and more comorbidities (OR 0.85).

CONCLUSION

Despite adherence to ULT linked to better outcomes for flares and tophi, the more adherent Chinese male patients and those with more comorbidities had decreased target SU attainment. Differences in adherence of Chinese gout patients compared to several primarily Western studies emphasize the importance of not stereotyping gout patients for projected nonadherence. Results underline the dual importance of identifying gout patients more likely to be ULT-adherent and leveraging adherence to drive treatment to SU target.

Effect of Food on the Pharmacokinetics and Pharmacodynamics of a Single Oral Dose of SHR4640, a Selective Urate Transporter 1 Inhibitor, in Healthy Chinese Male Volunteers

SHR4640, also named as ruzinurad, is a selective human urate transporter 1 (URAT1) inhibitor developed for the treatment of hyperuricemia and gout. This study evaluated the high-fat, high-calorie food effect on the pharmacokinetics and pharmacodynamics of SHR4640 in healthy Chinese male volunteers. In this open-label, randomized, 2-period crossover phase 1 trial, 14 healthy male subjects were randomized to receive a single 10-mg dose of SHR4640 under both fasted and fed conditions. The washout period was 7 days. Blood samples were collected for pharmacokinetic and pharmacodynamic analysis. Pharmacokinetic parameters were analyzed by a noncompartmental method. The safety of the drug was also evaluated in the trial. A total of 14 healthy male volunteers were enrolled in the study, and finally 13 healthy volunteers completed the study. A single 10-mg dose of SHR4640 was safe and well tolerated in healthy Chinese male volunteers. After single-dose administration of SHR4640, the 90%CIs of the geometric mean ratios of the area under the plasma concentration-time curve from time 0 to the last quantifiable concentration and the area under the plasma concentration-time curve from time 0 to infinity were within the equivalence criteria of 0.80-1.25. The 90%CIs of maximum plasma concentration was slightly outside the lower limit of bioequivalent criteria, with about 13.40% decrease in the fed versus fasted condition. The time to maximum concentration was slightly delayed under the fasted condition. A single 10-mg dose of SHR4640 was safe and well tolerated in this trial. The main pharmacokinetic parameters and serum uric acid lowering of SHR4640 were not affected by food effect; thus, SHR4640 can be recommended to be administered with or without food.

The role of lipid profile in the relationship between particulate matters and hyperuricemia: A prospective population study

CONTEXT

Recent studies in specific population subgroups (e.g., pregnant women) have suggested PM exposure increases the risk of hyperuricemia. However, no studies have examined this in the general population. Furthermore, the underlying mechanism through which PM impacts hyperuricemia risk is poorly understood.

OBJECTIVE

To assess the association between long-term exposure to PM and risk of hyperuricemia and whether this association is mediated by lipid profile.

METHODS

We included 5939 participants in Southwest China from the China Multi-Ethnic Cohort (baseline 2018-2019, follow-up 2020-2021). Long-term PM pollutants (PM₁, PM_2.5, PM₁₀) exposure for each individual was represented by the three-year average PM levels before the baseline survey. Hyperuricemia at follow-up was defined as the serum uric acid above 7.0 mg/dL in men and 6.0 mg/dL in women. Serum lipids were measured at baseline including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG). The association of PM with hyperuricemia was accessed through logistic regression. The potential mediation effects of serum lipids were evaluated through causal mediation analyses.

RESULTS

A total of 837 participants were newly diagnosed with hyperuricemia. The odds ratios of hyperuricemia associated with an interquartile range (IQR) increase in PM₁, PM_2.5, and PM₁₀ (IQR: 21.10, 25.78, 30.43 μg m^-3) were 1.72 (95% CI: 1.23, 2.39), 2.68 (95% CI: 1.59, 4.49), and 1.81 (95% CI: 1.20, 2.72), respectively. The association between PM_2.5, PM₁, and PM₁₀ on hyperuricemia was mediated by HDL-C (10%) and LDL-C (3%).

CONCLUSION

Higher particulate matter exposure was associated with higher hyperuricemia incidence. The decline in HDL-C and rise in LDL-C partially mediated this association. These findings were conducive to scientific research about the underlying mechanism of PM on hyperuricemia.

Inflammasomes and their roles in arthritic disease pathogenesis

The inflammasome is a molecular platform that is created in the cytosolic compartment to mediate the host immunological response to cellular injury and infection. Caspase-1 may be activated by the inflammasome, which leads to the generation of the inflammatory cytokines interleukin-1β (IL-1β) and IL-18 and the beginning of pyroptosis, which is a type of proinflammatory cell death. Scientists have identified a number of different inflammasomes in the last 2 decades. The NLRP3 inflammasome has been studied the most, and its activity may be triggered by a broad range of different inducers. However, activation of the NLRP3 inflammasome in a manner that is not properly controlled is also a factor in the etiology of many human illnesses. Accumulating evidence indicates that the NLRP3 inflammasome plays a significant role in the innate and adaptive immune systems and the development of various arthritic illnesses, such as rheumatoid arthritis, ankylosing spondylitis, and gout. The present review provides a concise summary of the biological properties of the NLRP3 inflammasome and presents the fundamental processes behind its activation and control. We discuss the role of the inflammasome in the pathogenesis of arthritic diseases, such as rheumatoid arthritis, ankylosing spondylitis, and gout, and the potential of newly developed therapies that specifically target the inflammasome or its products for the treatment of inflammatory diseases, with a particular emphasis on treatment and clinical application.

Dynamin-Related Protein 1 Is Involved in Mitochondrial Damage, Defective Mitophagy, and NLRP3 Inflammasome Activation Induced by MSU Crystals

Excessive generation of reactive oxygen species (ROS) has great impacts on MSU crystal-induced inflammation. Drp1-dependent mitochondrial fission is closely associated with mitochondrial ROS levels. However, whether Drp1 signaling contributes to MSU crystal-induced inflammation remains unclear. Mice bone marrow-derived macrophages (BMDMs) were primed with LPS and then stimulated with MSU suspensions for 12 h. The protein levels associated with mitochondrial dynamics, oxidative stress, and mitophagy were detected by Western blot. BMDMs were loaded with MitoTracker Green probe to detect mitochondrial morphology. To measure mitochondrial reactive oxygen species (ROS) and total ROS levels, cells were loaded, respectively, with MitoSOX and DHE probes. The effects of Mito-TEMPO, an antioxidant that targets the mitochondria or DRP1 inhibitor (Mdivi-1) on MSU crystal-induced peritonitis and arthritis mouse models, were evaluated. Our study revealed that MSU crystal stimulation resulted in elevation of mitochondrial fragmentation of BMDMs. Treatment with Mito-TEMPO or Drp1 knockdown significantly ameliorated the mitochondrial damage induced by MSU crystals. BMDMs exposure to MSU crystals increased the expression of auto/mitophagy marker proteins and promoted the fusion of mitophagosomes with lysosomes, leading to accumulation of mitolysosomes. Drp1 knockdown alleviated defective mitophagy and activation of the NLRP3 inflammasome in MSU crystal-treated BMDMs. This study indicates that there is crosstalk between mitochondrial ROS and Drp1 signaling in MSU crystal-induced inflammation. Drp1 signaling is involved in MSU crystal-induced mitochondrial damage, impaired mitophagy and NLRP3 inflammasome activation.

Trend dynamics of gout prevalence among the Chinese population, 1990-2019: A joinpoint and age-period-cohort analysis

Background

The burden of gout is increasing worldwide, which places a heavy burden on society and healthcare systems. This study investigates the independent effects of age, period, and cohort on the gout prevalence from 1990 to 2019 in China, compares these effects by gender and then predicts the future burden of gout over the next decade.

Methods

The data were obtained from the Global Burden of Disease (GBD) study in 2019. Joinpoint regression model was employed to calculate the annual percentage change (APC) in gout prevalence, and the age-period-cohort analysis was utilized to estimate the independent effects of age, period, and cohort. ARIMA model was extended to predict the gout epidemic in 2020-2029.

Results

In 2019, there were 16.2 million cases of gout in China, with an age-standardized prevalence rate (ASPR) of 12.3‰ and 3.9‰ in men and women, respectively. During 1990-2019, the ASPR of gout was increasing significantly, with an average APC of 0.9%. The periods of 2014-2017 and 2001-2005 were "joinpoint" for men and women (APC: 6.3 and 5.6%). The age-period-cohort analyses revealed that the relative risk (RR) of developing gout increased with age, peaking at 70-74 years in men (RR_age(70-74) = 162.9) and 75-79 years in women (RR_age(75-79)=142.3). The period effect trended upward, with a more rapid increase in women (RR_period(2019) = 2.31) than men (RR_period(2019) = 2.23). The cohort effect generally peaked in the earlier cohort born in 1905-1909 for both sexes. Gout prevalence showed a strong positive correlation with the consumption of meat and aquatic products (r_meat = 0.966, r_{aquaticproducts} = 0.953). Within 2029, the ASPR of gout was projected to be 11.7‰ and 4.0‰ in men and women, respectively.

Conclusion

The prevalence of gout is increasing at an alarming rate in China; thus, it is necessary to provide targeted health education, regular screening, and accessible urate-lowering therapy healthcare to prevent and protect against gout in China, particularly in older women.

Uric Acid Levels Are Associated with Bone Mineral Density in Mexican Populations: A Longitudinal Study

Background: Inconsistent epidemiological evidence between uric acid (UA) and bone mineral density (BMD) has been observed. Therefore, we evaluated the association between UA and BMD in Mexican adults. Methods: This analysis was conducted on 1423 participants from the Health Workers Cohort Study. We explored cross-sectional associations using linear regression and longitudinal associations using fixed-effects linear regression by sex and age groups (<45 and ≥45 years). Results: In females <45 years old, the cross-sectional analysis showed that UA levels were positively associated with total hip BMD. However, in the longitudinal analysis, we observed a negative association with the femoral neck and lumbar spine BMD. In contrast, in males <45 years old, we found an increase in total hip and femoral neck BMD in the groups with high levels of UA in the longitudinal association. On the other hand, in females ≥45 years old, we observed a longitudinal association between UA and loss of BMD at different sites. We did not observe an association between UA levels and BMD in males ≥45 years old. Conclusions: Our results suggest higher serum UA levels are associated with low BMD at different skeletal sites in Mexican females. Further studies are needed to delineate the underlying mechanisms behind this observation.

Linear and non-linear Mendelian randomization analyses of sex-specific associations between sleep duration and hyperuricemia

Background

Observational studies have suggested a potential non-linear association between sleep duration and hyperuricemia. However, the causal nature and sex-specific differences are poorly understood. We aimed to determine the shape of sex-specific causal associations between sleep duration and hyperuricemia in the UK Biobank.

Methods

Logistic regression was used to investigate the observational association between self-reported sleep duration and hyperuricemia among 387,980 white British participants (mean age: 56.9 years and 46.0% males). Linear and non-linear Mendelian Randomization (MR) analyses were performed to assess the causal association between continuous sleep duration and hyperuricemia. The causal effects of genetically predicted short (<7 h) and long (>8 h) sleep durations on hyperuricemia were further estimated, respectively.

Results

Traditional observational analysis suggested U- and J-shaped associations between sleep duration and hyperuricemia in females and males, respectively. Linear MR did not support the causal effect of sleep duration on hyperuricemia. Non-linear MR demonstrated an approximately U-shaped causal association between continuous sleep duration and hyperuricemia in overall participants and females, but not in males. Genetically predicted short sleep duration was significantly associated with hyperuricemia in females (OR [95% CI]: 1.21 [1.08–1.36]; P = 0.001), but not in males (1.08 [0.98–1.18]; P = 0.137). By contrast, genetically predicted long sleep duration was not significantly associated with the risk of hyperuricemia in either females or males.

Conclusion

Genetically predicted short sleep duration is a potential causal risk factor for hyperuricemia for females but has little effect on males. Long sleep duration does not appear to be causally associated with hyperuricemia.

The Prevalence of Hyperuricemia and Its Correlates among Adults in China: Results from CNHS 2015-2017

This study aimed to investigate the prevalence of hyperuricemia (HUA) and associated risk factors in Chinese adults aged 18 to 59 years. All the data were collected from the China Nutrition and Health Surveillance during the period 2015–2017, which adopted a stratified, multistage, random sampling method on a national scale. A total of 52,627 participants aged 18 years or older were included in this study. The definition of hyperuricemia was 420 μmol/L for male and 360 μmol/L for female. The Rao–Scott chi-square test was used to compare the differences in prevalence between or among the subgroups. A weighted two-level multivariate survey-logistic regression was used to detect the correlations between HUA and demographic, physical, lifestyle and metabolic factors. The total prevalence of HUA was 15.1%, and that was higher in male, current smokers, higher BMI and less physical activities subgroups, and also in noninfectious chronic diseases (NCDs) subgroups. The subgroups of non-vegetarian diet, insufficient vegetable intakes and excessive red meat and alcohol intakes had significantly higher HUA prevalence. After introducing all the variables in the survey-logistic regression, gender, age, BMI, physically active, hypertension, diabetes mellitus, bean and nut intake, vegetable intake, red meat intake, alcohol consumption and vegetarian were associated with HUA. Among the significant variables, age and physical active served as a protective factor, and BMI showed to be a risk factor for HUA. Hypertension and dyslipidemia could increase the risk for HUA, while diabetes mellitus was shown a negative association with it. For dietary factors, vegetarian diet, sufficient beans and nuts and vegetables intake could lower the risk of HUA, but more alcohol could increase the risk of HUA. Dietary factor played a key role in HUA. It suggested that the intervention of dietary factor should receive more attention to ameliorate the high prevalence of HUA in China.

The Role of the "Anti-Inflammatory" Couple for the Management of Hyperuricemia With Deposition

INTRODUCTION

Gout is the most prevalent inflammatory crystal arthropathy worldwide and is a chronic disease requiring strict, lifelong adherence to drug therapy and healthy lifestyles. Gout has a heavy burden on the patient's sexual health, owing to the associated inflammatory status, long-term complications, and chronic pain; however, the effects of gout also extend to the partner's sexual health.

AIMS

We aimed to investigate how the presence of a partner could influence the complex interaction between risk factors for sexual dysfunctions in gout in order to define novel strategies to improve sexual health and disease management.

METHODS

Clinical and experimental data on the role of the couple in chronic diseases, as well as on the association between gout and sexual health, were searched through Pubmed.

MAIN OUTCOME MEASURES

Evidence from studies describing how the presence of a couple and leveraging sexual health can improve management and clinical outcomes for chronic diseases.

RESULTS

Treatment adherence can improve the sexual health of gout patients and their partners; likewise, by leveraging sexual health, it would be possible to promote better health-seeking behaviors, ultimately improving gout management.

CLINICAL IMPLICATIONS

Promoting awareness of the sexual health relevance of gout can potentially be a pivotal strategy to improve disease management and prevent the progression of sexual dysfunctions from subclinical to overt forms.

STRENGTHS AND LIMITATIONS

Identifying a bidirectional association between sexual health and disease management paves the way for improved disease control and can potentially prevent the development of sexual dysfunctions in couples affected by gout. However, the relevance of the couple has not been adequately addressed in gout management, and most evidence comes from other chronic diseases.

CONCLUSION

Improving gout management results in better sexual health, and vice-versa promoting better sexual health can improve disease control for gout. The presence of a partner improves the behavioral well-being of gout patients, with beneficial effects on both sexual health and gout management. Sansone A, Reisman Y, Meto S, et al. The Role of the "Anti-Inflammatory" Couple for the Management of Hyperuricemia With Deposition. Sex Med 2022;10:100562.

Novel Insights into the Effects of Genetic Variants on Serum Urate Response to an Acute Fructose Challenge: A Pilot Study

Studies have shown that genetic variations can influence metabolic response to nutrient intake, and that diets rich in fructose contribute to hyperuricemia. In this pilot study, our aim was to determine the variability of serum urate in response to an acute fructose challenge and to investigate if genetic variants would affect this response in young to middle-aged adults who self-reported as Black or White. Fifty-seven participants consumed a fructose-rich beverage after an overnight fast. Blood was drawn at five time points (baseline, 30, 60, 120, and 180 min after consumption). Thirty urate-related single nucleotide polymorphisms (SNPs) were analyzed for their associations with baseline serum urate and its percent changes, using a two-step modeling approach followed by meta-analysis. At baseline, serum urate (mg/dL, mean ± SD) was higher in Whites (5.60 ± 1.01 vs. 5.37 ± 0.96), men (6.17 ± 1.14 vs. 5.24 ± 0.79), and those with obesity (5.69 ± 1.08 vs. 5.42 ± 1.06 vs. 5.34 ± 0.80). Three SNPs were significantly associated with baseline serum urate or its percent changes, and six SNPs were nominally associated with percent changes in serum urate. In summary, our results showed that genetic variants could play a role in short-term urate metabolism.

Association of Visceral Fat Area and Hyperuricemia in Non-Obese US Adults: A Cross-Sectional Study

This study aimed to investigate the relationship between visceral fat area (VFA) and hyperuricemia (HUA) among non-obese adults. We extracted data from 6224 US adults aged 20−59 years from the National Health and Nutrition Examination Survey (NHANES) from 2011−2018. The VFA was divided into four quartiles (Q1−Q4). We used multivariable logistic regression models to control for known confounders. A generalized additive model (GAM) and restricted cubic spines were used to examine the association between VFA and HUA stratified by sex, and a two-piecewise linear regression model was used to calculate the threshold effect among males. The results revealed that the prevalence of HUA was 11.8% (men 15.8%, women 7.2%). In the fully adjusted model, there was a positive association between VFA and HUA [as a quartile variable, Q4 vs. Q1, odds ratio (OR): 3.77 and 95% confidence interval (CI): (2.47~5.75), p < 0.001, p for trend < 0.001; as a continuous variable, per 10 cm2 increment, OR (95%CI):1.10(1.07,1.14), p < 0.001]. Besides, this positive association remained significantly stratified by sex. Interestingly, we observed a nonlinear dose-response relationship between VFA and HUA in males (inflection point: 107.46 cm2). In conclusion, our study confirmed a significant positive relationship between VFA and HUA among non-obese adults and remained statistically significant when stratified by sex.

Research progress of risk factors and early diagnostic biomarkers of gout-induced renal injury

Gout renal injury has an insidious onset, no obvious symptoms, and laboratory abnormalities in the early stages of the disease. The injury is not easily detected, and in many cases, the patients have entered the renal failure stage at the time of diagnosis. Therefore, the detection of gout renal injury–related risk factors and early diagnostic biomarkers of gout renal injury is essential for the prevention and early diagnosis of the disease. This article reviews the research progress in risk factors and early diagnostic biomarkers of gout renal injury.

Individualized Homeopathic Medicines in Treatment of Hyperuricemia: Evaluation by Double-Blind, Randomized, Placebo-Controlled Trial

INTRODUCTION

 Hyperuricemia (HU) is a major health issue in India and across the globe. It increases the disease burden and hampers quality of life. This study was aimed at exploring the effects of individualized homeopathic medicines (IHMs) against placebo in the treatment of HU.

METHODS

 This double-blind, randomized, placebo-controlled trial was conducted on 60 patients suffering from HU in the outpatient department of D. N. De Homoeopathic Medical College and Hospital, Kolkata. Each patient received either IHMs or identical-looking placebos, along with advice on dietary modifications irrespective of codes. Serum uric acid (SUA) level was the primary outcome measure; the HU quality of life questionnaire (HUQLQ) and the Measure Yourself Medical Outcome Profile version 2 (MYMOP-2) were the secondary outcomes; all measured at baseline, and every month, up to 3 months. Group differences were examined by two-way (split-half) repeated-measures analysis of variance after adjusting for baseline differences. Significance level was set at p ≤0.05, two-tailed.

RESULTS

 The intention-to-treat sample (n = 58) was analyzed. Between-group differences in SUA levels (F _{1, 56} = 13.833, p <0.001), HUQLQ scores (F _{1, 56} = 32.982, p <0.001) and MYMOP-2 profile scores (F _{1, 56} = 23.873, p <0.001) were statistically significant, favoring IHMs against placebos, with medium to large effect sizes. Calcarea carbonica and Pulsatilla nigricans were the most frequently prescribed medicines. No serious adverse events were reported from either of the groups.

CONCLUSION

 IHMs showed significantly better results than placebos in reducing SUA levels and improving quality of life in patients suffering from HU.

TRIAL REGISTRATION

 CTRI/2019/10/021503; UTN: U1111-1241-1431.

An integrated study of Shenling Baizhu San against hyperuricemia: Efficacy evaluation, core target identification and active component discovery

ETHNOPHARMACOLOGICAL RELEVANCE

Shenling Baizhu San (SLBZ) is a famous Traditional Chinese Medicine (TCM) formula that strengthens the spleen for replenishing qi, removing dampness, and inducing diuresis to relieve diarrhea. Combining the TCM interpretation that dampness is a vital pathogenesis factor in hyperuricemia occurrence and development, SLBZ has excellent potential against hyperuricemia from the perspective of TCM theories.

AIM OF THE STUDY

This study aimed to investigate the efficacy of SLBZ against hyperuricemia and its possible mechanism with emphasis on the active components and the core targets.

MATERIALS AND METHODS

In the present study, we employed meta-analysis and a hyperuricemia quail model to evaluate the uric acid-lowering effect of SLBZ. Bodyweight, serum uric acid, and excreta uric acid levels in quails were assessed. Subsequently, we analyzed the potential active components and core targets of SLBZ against hyperuricemia by network pharmacology and calculated their interaction using molecular docking. Furthermore, the hyperuricemia rats treated with interfering agents of core targets were established to determine the central role of selected targets in hyperuricemia progression. Besides, we isolated and characterized the primary renal tubular epithelial cells of quails to verify the active components and core targets of SLBZ against hyperuricemia. Western blotting was used to observe the expression of core targets treated with active components under the stimulation of interfering agents.

RESULTS

Data from meta-analysis and animal experiments showed that SLBZ could work effectively against hyperuricemia. Hyperuricemia quails treated with SLBZ displayed significantly reduced serum uric acid levels accompanied by increased excretion of uric acid. According to network pharmacology and molecular docking results, 34 potential active components and the core target peroxisome proliferator-activated receptor gamma (PPARγ) for SLBZ against hyperuricemia were identified. The decreased serum uric acid levels in hyperuricemia rats treated with rosiglitazone, an agonist of PPARγ, confirms the essential role of PPARγ in the pathological process of hyperuricemia. Moreover, we first successfully isolated and characterized the primary renal tubular epithelial cells of quails and observed enhanced phosphorylation of PPARγ at Ser273 in cells handled with high-level uric acid. Whereas, the enhanced expression of p-PPARγ Ser273 could be down-regulated by luteolin and naringenin, two active components of SLBZ against hyperuricemia.

CONCLUSION

In summary, SLBZ is a promising anti-hyperuricemia agent, and luteolin and naringenin are the active components for SLBZ against hyperuricemia by down-regulating phosphorylation of PPARγ at Ser273.

Probiotics, bioactive compounds and dietary patterns for the effective management of hyperuricemia: a review

Hyperuricemia is closely linked with an increased risk of developing hypertension, diabetes, renal failure and other metabolic syndromes. Probiotics, bioactive compounds and dietary patterns are safe cost-efficient ways to control hyperuricemia, whereas comprehensive reviews of their anti-hyperuricemic mechanisms are limited. This review summarizes the roles of probiotics, bioactive compounds and dietary patterns in treating hyperuricemia and critically reviews the possible mechanisms by which these interventions exert their activities. The dietary patterns are closely related to the occurrence of hyperuricemia through the indirect action of gut microbiota or the direct effects of host purine metabolism. The Mediterranean and Dietary Approaches to Stop Hypertension diets help reduce serum uric acid concentrations and thus prevent hyperuricemia. Meanwhile, probiotics alleviate hyperuricemia by ways of absorbing purine, restoring gut microbiota dysbiosis and inhibiting xanthine oxidase (XO) activity. Bioactive compounds such as polyphenols, peptides and alkaloids exert various anti-hyperuricemic effects, by regulating urate transporters, blocking the active sites of XO and inhibiting the toll-like receptor 4/nuclear factor kappa B signaling pathway and NOD-, LRR- and pyrin domain-containing protein 3 signaling pathway. This review will assist people with hyperuricemia to adopt a healthy diet and contribute to the application of natural products with anti-hyperuricemic activity.

Uric Acid as a Risk Factor for Cardiovascular Diseases

Recently, hyperuricemia and its association with cardiovascular disease have been receiving more and more attention. The article talks about the role of uric acid in the body, the reasons for its increase and the impact of elevated uric acid levels on the cardiovascular system. The mechanisms of influence of hyperuricemia on the development and progression of cardiovascular diseases are presented. Medicinal and non-drug ways to reduce the level of uric acid in the blood are considered. From non-drug methods, attention is focused on the hypopurine diet, adequate drinking regimen and normalization of body weight. Separately, the effect on the level of uric acid of various drugs used in clinical practice is considered. In the light of current clinical guidelines, the issue of the need to prescribe drug therapy for asymptomatic hyperuricemia is discussed.

Higher neutrophil to lymphocyte ratio is associated with renal dysfunction and cardiac adverse remodeling in elderly with metabolic syndrome

Background

Previous studies have shown that metabolic syndrome (MetS) is associated with increased systemic inflammation and cardiac mortality in elderly subjects. However, information on the association of inflammation markers with cardiac adverse remodeling is limited in the elderly with MetS. Therefore, we investigated whether the inflammatory marker neutrophil/lymphocyte ratio (NLR) is associated with the cardiac adverse remodeling in Chinese elderly with MetS.

Methods

A total of 1,087 hospitalized Chinese elderly (aged ≥ 65 years) with MetS were collected retrospectively. The cross-sectional data of echocardiography and clinical parameters were compared among quartile NLR groups.

Results

In the elderly with MetS, higher quartile NLR (≥3.83) was found to be associated with male gender, older age, lower estimated glomerular filtration rate (eGFR), and cardiac left ventricular (LV) dilatation (all p <0.05).

Conclusion

Higher NLR is associated with male gender, older age, renal dysfunction, and cardiac adverse remodeling in Chinese elderly with MetS.

TET2-mutant clonal hematopoiesis and risk of gout

Gout is a common inflammatory arthritis caused by precipitation of monosodium urate (MSU) crystals in individuals with hyperuricemia. Acute flares are accompanied by secretion of proinflammatory cytokines, including interleukin-1β (IL-1β). Clonal hematopoiesis of indeterminate potential (CHIP) is an age-related condition predisposing to hematologic cancers and cardiovascular disease. CHIP is associated with elevated IL-1β, thus we investigated CHIP as a risk factor for gout. To test the clinical association between CHIP and gout, we analyzed whole exome sequencing data from 177 824 individuals in the MGB Biobank (MGBB) and UK Biobank (UKB). In both cohorts, the frequency of gout was higher among individuals with CHIP than without CHIP (MGBB, CHIP with variant allele fraction [VAF] ≥2%: odds ratio [OR], 1.69; 95% CI, 1.09-2.61; P = .0189; UKB, CHIP with VAF ≥10%: OR, 1.25; 95% CI, 1.05-1.50; P = .0133). Moreover, individuals with CHIP and a VAF ≥10% had an increased risk of incident gout (UKB: hazard ratio [HR], 1.28; 95% CI, 1.06-1.55; P = .0107). In murine models of gout pathogenesis, animals with Tet2 knockout hematopoietic cells had exaggerated IL-1β secretion and paw edema upon administration of MSU crystals. Tet2 knockout macrophages elaborated higher levels of IL-1β in response to MSU crystals in vitro, which was ameliorated through genetic and pharmacologic Nlrp3 inflammasome inhibition. These studies show that TET2-mutant CHIP is associated with an increased risk of gout in humans and that MSU crystals lead to elevated IL-1β levels in Tet2 knockout murine models. We identify CHIP as an amplifier of NLRP3-dependent inflammatory responses to MSU crystals in patients with gout.