The prevalence of gout and hyperuricaemia in Australia: An updated systematic review

Gout and its management

Gout is a common and treatable chronic disease of monosodium urate crystal deposition. It is experienced as extremely painful episodes of joint inflammation that impact all aspects of the person's life. This Clinical Perspectives article provides an update on gout diagnosis, medications and strategies to improve the quality of gout care.

Estimation of adherence to urate-lowering therapy in people living with gout using Australia's Pharmaceutical Benefits Scheme and patient-reported dosing

AIMS

The aim of this study was to estimate adherence to urate-lowering therapy (ULT), predominately allopurinol, from Australia's Pharmaceutical Benefits Scheme (PBS) claims database in association with (1) patient-reported doses and (2) World Health Organization's (WHO) defined daily doses (DDD), namely, allopurinol (400 mg/day) or febuxostat (80 mg/day).

METHODS

Proportion of days covered (PDC) was calculated in 108 Gout App (Gout APP) trial participants with at least two recorded ULT dispensings in an approximately 12-month period before provision of intervention or control apps. Adherence was defined as PDC ≥80%. We measured the correlation between the two methods of calculating PDC using a Wilcoxon signed rank test. Agreement between ULT-taking status (self-reports) and ULT-dispensed status (PBS records) was tested with Cohen's kappa (κ), and positive and negative percent agreement.

RESULTS

Allopurinol was prescribed in 93.5% of participants taking ULT. Their self-reported mean daily dose (SD) was 291 (167) mg/day. Mean PDC (SD) for allopurinol was 83% (21%) calculated using self-reported dose, and 63% (24%) using WHO's DDD. Sixty-three percent of allopurinol users were identified as adherent (PDC ≥80%) using self-reported dose. There was good agreement between self-reported ULT use and PBS dispensing claims (κ = 0.708, P < .001; positive percent agreement = 90%, negative percent agreement = 82%).

CONCLUSIONS

Participant-reported allopurinol daily doses, in addition to PBS dispensing claims, may enhance confidence in estimating PDC and adherence compared to using DDD. This approach improves adherence estimations from pharmaceutical claims datasets for medications where daily doses vary between individuals or where there is a wide therapeutic dose range.

Overview of the pharmacokinetics and pharmacodynamics of URAT1 inhibitors for the treatment of hyperuricemia and gout

INTRODUCTION

Hyperuricemia is a common metabolic disease, which is a risk factor for gouty arthritis and ureteral stones and may also lead to cardiovascular and chronic kidney disease (CDK). Therefore, hyperuricemia should be treated early. Xanthine oxidase inhibitors (XOIs) and uricosuric agents (UAs), which target uric acid, are two types of medications that are used to treat gout and hyperuricemia. XOIs stop the body from producing excessive uric acid, while UAs eliminate it rapidly via the kidneys. Urate transporter 1 (URAT1) belongs to the organic anion transporter family (OAT) and is specifically localized to the apical membrane of the epithelial cells of proximal tubules. Unlike other organic anion transporter family members, URAT1 identifies and transports organic anions that are primarily responsible for urate transport.

AREAS COVERED

This article reviews the pharmacokinetics and pharmacodynamics of the existing URAT1 inhibitors to serve as a reference for subsequent drug studies.

EXPERT OPINION

The URAT1 inhibitors that are currently used as clinical drugs mainly include dotinurad, benzbromarone, and probenecid. Results indicate that RDEA3170 may be the most promising inhibitor, in addition to SHR4640, URC-102, and MBX-102, which are in the early stages of development.

Associations between vitamin C intake and serum uric acid in US adults: Findings from National Health and Nutrition Examination Survey 2011-2016

BACKGROUNDS

Dietary factors has been found to influence serum uric acid (SUA) levels. We further explored the associations between dietary and supplemental vitamin C intake and SUA in a large population-based study.

METHODS

The cross-sectional study included 6308 participants (3146 males and 3162 females) aged ≥20 years from the National Health and Nutrition Examination Survey (NHANES) 2011-2016 in the United States. The dietary vitamin C was log-transformed for statistical analysis. Hyperuricemia was defined as SUA concentrations >420 umol/L in males or >360 umol/L in females. The associations of dietary vitamin C and supplemental vitamin C with SUA levels and hyperuricemia risk were evaluated using weighted linear regression models and weighted multivariate logistic regression models, and a subgroup analysis stratified by gender was also conducted.

RESULTS

In this large-scale database study, there was a negative association between dietary vitamin C (log transformed) and SUA levels in US adults (β = -7.27, 95% CI: -11.58, -2.97). The inverse relationship existed among males but not females (P for interaction = 0.02). There was inverse correlation between dietary vitamin C (log transformed) and hyperuricemia risk (OR = 0.68, 95% CI: 0.57, 0.81), especially in males compared to females determined through an interaction test (P = 0.04). There were no associations between supplemental vitamin C and SUA levels (β = 1.00 (95% CI: -4.44, 6.44) or hyperuricemia risk (OR = 0.98 (95% CI: 0.78, 1.24). High-dosage supplemental vitamin C (>300 mg) and hyperuricemia risk were not associated (OR = 1.04, 95% CI: 0.69, 1.56).

CONCLUSIONS

This study demonstrated that there were negative associations between dietary vitamin C and SUA levels and hyperuricemia risk among US adults. The inverse correlations between dietary vitamin C and hyperuricemia risk were more significant in males compared to females. There were no associations between supplemental vitamin C and SUA levels or hyperuricemia risk.

Evaluating the effectiveness and safety of acupuncture on serum uric acid in asymptomatic hyperuricemia population: a randomized controlled clinical trial study protocol

Background

The clinical dangers of asymptomatic hyperuricemia to human health have become increasingly prominent over the past 20 years. Previous studies have shown the potential benefits of acupuncture on uric acid levels in the body. However, definitive evidence is lacking. Our objective is to evaluate the efficacy and safety of acupuncture on serum uric acid (SUA) in individuals with asymptomatic hyperuricemia.

Methods

This is a randomized, single-blind, sham-controlled trial. A total of 180 eligible patients with asymptomatic hyperuricemia will be recruited at three hospitals in China. Patients will be randomly assigned in a 1:1 ratio to receive 16 sessions of manual acupuncture or sham acupuncture for 8 weeks. Patients will be followed up for 12 weeks. The primary outcome will be the change in SUA levels at week 8 after randomization. Secondary outcomes will include dynamic changes in SUA levels, efficacy rates, proportion of gout flare, body weight, and acute medication intake. The MGH Acupuncture Sensation Scale and adverse events related to acupuncture will be measured after each treatment. A blinding assessment will be performed on patients who receive at least one session of acupuncture. Data analyses will be performed on a full analysis set and a per-protocol set.

Ethics and dissemination

Ethics approval has been obtained from the Clinical Trial Ethics Committee of Tongji Medical College, Huazhong University of Science and Technology (approval no. 2021-S135). Written informed consent will be obtained from enrolled patients. The findings will be disseminated in a peer-reviewed journal.

Clinical trial registration

ClinicalTrials.gov identifier, NCT05406830.

The disproportionately large contribution of the Māori and Pacific Islander community to the healthcare burden of gout in Western Sydney

BACKGROUND

Gout is a common chronic inflammatory disorder due to monosodium urate deposition, which results in severe inflammatory arthritis. It is particularly common in those of Māori or Pacific Islander heritage. There is a significant number of this at-risk ethnic group in western Sydney.

AIMS

To determine the healthcare burden of gout in Western Sydney.

METHODS

We characterised patients managed in the emergency departments (EDs) of the four Western Sydney Local Health District (WSLHD) hospitals and those admitted for gout as the primary or secondary diagnosis from 1 January 2017 to 31 December 2018.

RESULTS

There were 472 patients managed in ED on 552 occasions at a direct cost to the LHD of A$367 835. Those of Māori or Pacific Islander ethnicity comprised 25.2% (n = 119/472), while half (n = 39/80) of those managed in ED for gout on two or more occasions were of Māori or Pacific Islander ethnicity. Overall, 310 patients were admitted with gout as the principal diagnosis on 413 occasions at a cost of A$1.73 million. Seventy-five (24.2%) of the 310 patients were of Māori or Pacific Islander heritage. A total of 584 WSLHD inpatients had gout as a secondary diagnosis. This was associated with 714 admissions.

CONCLUSIONS

The disproportionately large healthcare burden of gout in Western Sydney from the relatively small Māori and Pacific Islander population needs attention. Urgent culturally appropriate interventions to address gout are required to address this inequality.

Optimizing adherence to allopurinol for gout: patients' perspectives

AIMS

Poor adherence to allopurinol among people with gout contributes to suboptimal gout management. This study sought to understand the facilitators and barriers to allopurinol adherence across the three stages of medication adherence, and patient perspectives on strategies to improve adherence, including self-monitoring urate concentration.

METHODS

Semi-structured interviews were conducted with 26 people with gout, previously or currently taking allopurinol. De-identified verbatim transcripts were thematically analysed using an inductive and deductive approach.

RESULTS

Facilitators of adherence during allopurinol initiation were motivation to prevent gout flares and trust in the advice of their healthcare professionals (HCPs). Reluctance to commence long-term medication was a barrier to allopurinol initiation. Believing in the effectiveness and necessity of allopurinol and reminder systems were facilitators of implementation. Barriers to implementation included forgetfulness, gout flares and limited feedback on allopurinol's effectiveness. Patients discontinued therapy when allopurinol was perceived as ineffective or unnecessary. Discontinuation coincided with patients experiencing gout flares while adhering to allopurinol and receiving suboptimal advice about gout management. Patients identified receiving accurate advice from HCPs and regular urate monitoring for feedback on allopurinol's effectiveness as potential strategies to improve adherence. Perceived benefits of self-monitoring urate as a strategy to promote adherence included the ability to self-manage gout and make informed decisions about allopurinol therapy with their HCP.

CONCLUSION

Patient perceptions of the effectiveness and necessity of allopurinol influenced intentional adherence during medication initiation, implementation and discontinuation. Strategies that inform patients of their urate control and provide accurate medical advice have the potential to improve adherence to allopurinol.

Uric acid en route to gout

Gout and hyperuricemia (HU) have generated immense attention due to increased prevalence. Gout is a multifactorial metabolic and inflammatory disease that occurs when increased uric acid (UA) induce HU resulting in monosodium urate (MSU) crystal deposition in joints. However, gout pathogenesis does not always involve these events and HU does not always cause a gout flare. Treatment with UA-lowering therapeutics may not prevent or reduce the incidence of gout flare or gout-associated comorbidities. UA exhibits both pro- and anti-inflammation functions in gout pathogenesis. HU and gout share mechanistic and metabolic connections at a systematic level, as shown by studies on associated comorbidities. Recent studies on the interplay between UA, HU, MSU and gout as well as the development of HU and gout in association with metabolic syndromes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular, renal and cerebrovascular diseases are discussed. This review examines current and potential therapeutic regimens and illuminates the journey from disrupted UA to gout.

In vitro xanthine oxidase inhibitory and in vivo anti-hyperuricemic properties of sodium kaempferol-3'-sulfonate

Xanthine oxidase (XO), a key enzyme in purine catabolism, catalyzes the oxidation of xanthine to uric acid in the body, but overproduction of uric acid may lead to hyperuricemia. This study aims to investigate in vitro XO inhibitory and in vivo anti-hyperuricemic properties of sodium kaempferol-3'-sulfonate (KS). The kinetic analysis indicates that KS is a reversible competitive inhibitor and has significant inhibitory effects on XO activity with an IC₅₀ value of 0.338 μM. Fluorescence spectra suggested that KS could cause fluorescence quenching and conformational changes of XO due to the formation of a KS-XO complex. Molecular docking studies demonstrated that KS interacted with several amino acid residues of XO by the π-π stacking, hydrogen bonds, and hydrophobic interactions. The inhibitory mechanism of KS on XO activity might be the insertion of KS into the active site of XO to prevent the entrance of the substrate xanthine and induce conformational changes of XO. The results carried out in hyperuricemic mice showed that KS reduced serum XO activity, serum uric acid (UA), creatinine (CRE), and urea nitrogen (BUN) levels, as well as alleviating renal histopathological injury. These findings suggest that KS may be a new potent XO inhibitor against hyperuricemia-related diseases.

Determination of purines in prepackaged food using optimum acid hydrolysis followed by high performance liquid chromatography

A high performance liquid chromatography was established to determine purine content of prepackaged food. Chromatographic separation was performed on Agilent5 TC-C18 column. Ammonium formate (10 mmol/L, pH = 3.385) and methanol (99:1) were used as mobile phase. Purine concentration and peak area showed good linear relationships in the range from 1 to 40 mg/L (guanine, hypoxanthine, adenine) and xanthine exhibited a good linear relationship ranged from 0.1 to 4.0 mg/L. Recoveries of four purines ranged from 93.03% to 107.42%. Purine content in prepackaged food was following: animal derived prepackaged food: 16.13-90.18 mg/100 g; beans and bean products: 66.36-157.11 mg/100 g; fruits and fruit products: 5.64-21.79 mg/100 g; instant rice and flour products: 5.68-30.83 mg/100 g; fungi, algae, fungi and algae products: 32.57-70.59 mg/100 g. This proposed method had good precision and accuracy with a wide linear range for detection of purine. Animal derived prepackaged food was purine-rich food, purine content of plant derived prepackaged food varied greatly.

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.

The Correlation between Traditional Chinese Medicine Constitution and Hyperuricemia and Gout: A Systematic Review and Meta-Analysis

Objective

To investigate the correlation between the constitution of traditional Chinese medicine (TCM) and hyperuricemia (HUA) and gout.

Method

Databases including China National Knowledge Infrastructure (CNKI), WanFang Data, China Science and Technology Journal Database (VIP), China Biology Medicine Disc (CBMdisc), PubMed, The Cochrane Library, Web of Science, and Excerpta Medical Database (Embase) were searched to collect observational studies about TCM constitution in HUA and gout from inception to November 21, 2021. The distribution of TCM constitution types in HUA and gout patients was presented by proportion, while the correlation was presented by odds ratio (OR) and 95% CI. Meta-analysis was performed using StataCorp Stata (STATA) version 16.0 software.

Results

Twenty-one cross-sectional studies and 10 case-control studies involving 38028 samples were included, among which 27526 patients were diagnosed with HUA and 2048 patients with gout. Phlegm-dampness constitution (PDC), damp-heat constitution (DHC), and qi-deficiency constitution (QDC) are the most common types, accounting for 24% (20%-27%), 22% (16%-27%), and 15% (12%-18%), respectively, in HUA patients, while DHC, PDC, and blood stasis constitution (BSC) accounted for 28% (18%-39%), 23% (17%-29%), and 11% (8%-15%), respectively, in gout patients. PDC and DHC were the main constitution types in patients with HUA or gout in south China, east China, north China, southwest China, northwest China, and northeast China. There was no difference in the distribution of PDC and QDC in male or female patients with HUA, while males with DHC in HUA were more common than females. The proportion of PDC or DHC among HUA patients was 1.93 times and 2.14 times higher than that in the general population (OR and 95% CI: 1.93 (1.27, 2.93), 2.14 (1.47, 3.13)), while the proportions of PDC, DHC, and BSC were 3.59 times, 4.85 times, and 4.35 times higher than that of the general groups (OR and 95% CI: 3.59 (1.65, 7.80), 4.85 (1.62, 14.57), and 4.35(2.33, 8.11)).

Conclusion

PDC, DHC, and QDC are the main constitution types of patients with HUA, while PDC and QDC may be the risk factors for HUA. DHC, PDC, and BSC are the main constitution types of patients with gout, and they may be the risk factors for gout. In clinical and scientific research, more attention should be paid to the relationship between the above-mentioned TCM constitution in HUA or gout. Nevertheless, because the quality of the included observational studies is low, more prospective cohort studies related to TCM constitution and HUA or gout can be carried out to verify the causality between TCM constitution and HUA or gout.

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.

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.

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.

Simulation of Febuxostat Pharmacokinetics in Healthy Subjects and Patients with Impaired Kidney Function Using Physiologically Based Pharmacokinetic Modeling

Febuxostat is recommend by the American College of Rheumatology Gout Management Guidelines as a first-line therapy for lowering the level of urate in patients with gout. At present, this drug is being prescribed mainly based on the clinical experience of doctors. The potential effects of clinical and demographic variables on the bioavailability and therapeutic effectiveness of febuxostat are not being considered. In this study, a physiologically based pharmacokinetic (PBPK) model of febuxostat was developed, thereby providing a theoretical basis for the individualized dosing of this drug in gout patients. The plasma concentration-time profiles corresponding to healthy subjects and gout patients with normal kidney function were simulated and validated; then, the model was used to predict the pharmacokinetic (PK) data of the drug in gout patients suffering from varying degrees of impaired kidney function. The error values (the predicted value/observed value) were used to validate the simulated PK parameters predicted by the PBPK model, including the area under the plasma concentration-time curve, the maximum plasma concentration, and time to maximum plasma concentration. Considering that to all error fold changes were smaller than 2 the PBPK model was. In subjects suffering from mild kidney impairment, moderate kidney impairment, severe kidney impairment, and end-stage kidney disease (ESRD), the predicted AUC_0-24h values increased by 1.62, 1.74, 2.27, and 2.65-fold, respectively, compared to gout patients with normal kidney function. Overall, the results showed that the PBPK model constructed in this study predict the pharmacokinetic changes in gout patients suffering from varying degrees of impaired kidney function. This article is protected by copyright. All rights reserved.

Medical Students' Perspective and Knowledge of Asymptomatic Hyperuricemia and Gout Management: A Cross-Sectional Study

The prevalence and incidence of gout doubled from 1990 to 2017. Therefore, we can expect that a number of doctors have come across a patient with gout in their daily practice. Hence, we wanted to investigate how familiar our medical students, as future medical professionals, are with gout. This cross-sectional survey included Medical Studies students from the two largest universities in Croatia: the University of Split School of Medicine, and the University of Zagreb School of Medicine, and included a total of 221 fifth or sixth year medical students. Most students gave correct answers to questions about treatment approach and non-pharmacological interventions in asymptomatic hyperuricemia (>80%). Less than 3% of all students agreed they knew enough about care for patients with asymptomatic hyperuricemia, whereas almost 15% thought they were well familiar with care for gout patients. Less than 8% of students considered their school education adequate on both topics, and less than 2% were aware of the existence of EULAR guidelines. Physicians lacking in the latest knowledge on the pathophysiology of gout, the influence of lifestyle, and genetic factors limits their ability to properly manage gout. With increasing prevalence, gout should be more represented in medical students’ education.

MicroRNAs Involved in the Therapeutic Functions of Noni (Morinda citrifolia L.) Fruit Juice in the Treatment of Acute Gouty Arthritis in Mice Induced with Monosodium Urate

We investigated the functions of microRNAs in the therapeutic effects of noni (Morinda citrifolia L.) fruit juice on mouse models of acute gouty arthritis induced with monosodium urate (MSU). Compared with the model group (treated with MSU), mice in both the positive control group (treated with both MSU and colchicine) and noni fruit juice group (treated with MSU and noni fruit juice) showed a significantly decreased degree of paw swelling in 5 days, as well as the contents of two types of proinflammatory cytokines (i.e., NALP3 and TNF-α). Based on the next-generation sequencing technology, a total of 3896 microRNAs (234 known and 3662 novel) were identified in mice treated with noni fruit juice. A large amount of differentially expressed miRNAs were identified in the noni fruit juice group, suggesting the significant effects of noni fruit juice on the mice with acute gouty arthritis, while the different patterns of change in the numbers of both upregulated and downregulated miRNAs in both noni fruit juice and positive control groups indicated that the mice of acute gouty arthritis may be regulated by differential mechanisms between the treatments of noni fruit juice and colchicine. The target genes of microRNAs involved in the pathogenesis and pathology of acute gouty arthritis in mice were identified and further annotated by both Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Our results revealed the therapeutic effects of noni fruit juice on acute gouty arthritis in mice with a group of microRNAs involved in the pharmacological mechanisms of noni fruit juice, providing scientific evidence to support both the agricultural cultivation and pharmacological significance of noni plants.