Cardiovascular Safety of Febuxostat or Allopurinol in Patients with Gout

Febuxostat provides renoprotection in patients with hyperuricemia or gout: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

It is unknown whether febuxostat can delay the progression of kidney dysfunction and reduce kidney endpoint events. The aim was to evaluate the renoprotective effect of febuxostat in patients with hyperuricemia or gout by performing a meta-analysis of randomized controlled trials (RCTs).

METHODS

MEDLINE, Web of science, EMBASE, ClinicalTrials.gov, and the Cochrane Central Register for Randomized Controlled Trials were searched. The main outcomes included kidney events (serum creatinine doubling or progression to end-stage kidney disease or dialysis). The secondary outcomes were the rate of change in the estimated glomerular filtration rate (eGFR) and changes in the urine protein or urine albumin to creatinine ratio from baseline to the end of follow-up. We used random-effects models to calculate the pooled risk estimates and 95% CIs.

RESULTS

A total of 16 RCTs were included in the meta-analysis. In comparison with the control group, the patients who received febuxostat showed a reduced risk of kidney events (RR = 0.56, 95% CI 0.37-0.84, p = 0.006) and a slower decline in eGFR (WMD = 0.90 mL/min/1.73 m2, 95% CI 0.31-1.48, p = 0.003). The pooled results also revealed that febuxostat use reduced the urine albumin to creatinine ratio (SMD = -0.21, 95% CI -0.41 to -0.01, p = 0.042).

CONCLUSION

Febuxostat use is associated with a reduced risk of kidney events and a slow decline in eGFR. In addition, the urine albumin to creatinine ratio decreased in febuxostat users. Accordingly, it is an effective drug for delaying the progression of kidney function deterioration in patients with gout.Systematic review registration: PROSPERO CRD42021272591.

Investigating the effects of rare ginsenosides on hyperuricemia and associated sperm damage via nontargeted metabolomics and gut microbiota

ETHNOPHARMACOLOGICAL RELEVANCE

In ancient times, ginseng was used for hyperuricemia treatment as described in the classic traditional Chinese medical text Shang Han Lun. Recent studies have shown that common ginsenosides and rare ginsenosides (RGS) are the main active compounds in ginseng. RGS have higher activity and are less studied in the treatment of hyperuricemia.

AIM OF THE STUDY

To determine whether RGS prevents and ameliorates potassium oxonate(PO)-induced hyperuricemia and concomitant spermatozoa damage in mice and the possible underlying mechanisms.

MATERIALS AND METHODS

Potassium oxonate (PO, 300 mg/kg) induced hyperuricemia in mice via the oral administration of RGS (50, 100, or 200 mg/kg) or allopurinol (ALL, 5 mg/kg) for 35 days. Uric acid (UA) and xanthine oxidase (XO) levels were measured to assess the degree of histopathological damage in the liver, kidney, and testis, and renal creatinine (CRE), urea nitrogen (BUN), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), and inflammatory factor (IL-1β) levels were measured to calculate the sperm density. Mechanisms were also explored based on blood and urine metabolomics and the gut microbiota.

RESULTS

In this study, we demonstrated that RGS containing Rg3, Rk1, Rg6, and Rg5 could reduce serum UA levels, inhibit serum and hepatic XO activity, reduce renal CRE and BUN levels, further restore renal SOD and GSH activities, reduce the accumulation of MDA in the kidneys, and attenuate the production of renal IL-1β. RGS was able to restore sperm density. Metabolomic analysis revealed that RGS improved sphingolipid metabolism, pyrimidine metabolism, and other metabolic pathways. 16S rDNA sequencing revealed that RGS could increase gut microbial diversity, restore the Firmicutes/Bacteroidetes (F/B) ratio, and adjust the intestinal microbial balance. Spearman's correlation analysis revealed a correlation between differentially metabolites and the gut microbiota. Lactobacillus and Akkermansia are the core genera.

CONCLUSION

RGS can be a candidate for the prevention and amelioration of hyperuricemia and concomitant sperm damage. Its mechanism of action is closely related to sphingolipid metabolism, pyrimidine metabolism, and the modulation of gut microbiota, such as Lactobacillus and Akkermansia.

Interaction-based screening, Monte Carlo Bayesian inference-based de novo design and in vitro verification of adenine-binding peptide

One of the main reasons for hyperuricemia is high purine intake. The primary strategy for treating hyperuricemia is blocking the purine metabolism enzyme. However, by binding the purine bases directly, we suggested a unique therapeutic strategy that might interfere with purine metabolism. There have been numerous reports of extensive interactions between proteins and purine bases. Adenine, constituting numerous protein co-factors, can interact with the adenine-binding motif. Using Bayesian Inference and Markov chain Monte Carlo sampling, we created a novel adenine-binding peptide Ile-Tyr-Val-Thr based on the structure of the adenine-binding motifs. Ile-Tyr-Val-Thr generates a semi-pocket that can clip the adenine within, as demonstrated by docking. Then, using thermodynamic techniques, the interaction between Ile-Tyr-Val-Thr and adenine was confirmed. The KD value is 1.50e-5 (ΔH = -20.2 kJ/mol and ΔG = -27.6 kJ/mol), indicating the high affinity. In brief, the adenine-binding peptide Ile-Tyr-Val-Thr may help lower uric acid level by blocking the absorption of food-derived adenine.

Co-delivery of indomethacin and uricase as a new strategy for inflammatory diseases associated with high uric acid

Uric acid is the final metabolite in humans. High level of uric acid chronically induces urate deposition, aggravates kidney damage, and concomitantly causes an increase in inflammatory factors. Alleviating acute inflammation and decreasing uric acid levels are the key points in the treatment of inflammatory diseases associated with high uric acid. However, a drug delivery system that combines anti-inflammatory and uric acid reduction functions at the same time remains a challenge to be settled. Here, we designed a nanocrystal-based co-delivery platform, IND Nplex, characterized by loading of indomethacin (IND) and uricase. Compared with free IND or uricase, IND Nplex possessed a better anti-inflammatory effect by restraining the release of inflammation-related factors in vitro. In addition, pharmacokinetic and biodistribution studies revealed that IND Nplex significantly prolonged the retention time in vivo and was more concentrated in the kidney. In acute gouty arthritis model rats, IND Nplex markedly relieved ankle joint swelling and mitigated synovial inflammation. In acute kidney injury model rats, IND Nplex indicated better biocompatibility and significant amelioration of renal fibrosis. Moreover, IND Nplex showed the effect of anti-inflammatory and improved renal function via determination of inflammatory factors and biochemical markers in the serum and kidney. In conclusion, these results indicate that IND Nplex exerts anti-inflammatory activity and uric acid-lowering effect and could become a promising candidate for the treatment of uric acid-related diseases.

A potential therapeutic agent for the treatment of hyperuricemia and gout: 3,4-Dihydroxy-5-nitrobenzaldehyde phenylthiosemicarbazide

Uric acid, the metabolic product of purines, relies on xanthine oxidase (XOD) for production. XOD is a target for the development of drugs for hyperuricemia (HUA) and gout. Currently, treatment options remain limited for gout patients. 3, 4-Dihydroxy-5-nitrobenzaldehyde (DHNB) is a derivative of the natural product protocatechualdehyde with good biological activity. In this work, we identify a DHNB thiosemicarbazide class of compounds that targets XOD. 3,4-Dihydroxy-5-nitrobenzaldehyde phenylthiosemicarbazone can effectively inhibit XOD activity (IC50 value: 0.0437 μM) and exhibits a mixed inhibitory effect. In a mouse model of acute hyperuricemia, a moderate dose (10 mg/kg.w) of 3,4-dihydroxy-5-nitrobenzaldehyde phenylthiosemicarbazide effectively controlled the serum uric acid content and significantly inhibited serum XOD activity. In addition, 3,4-Dihydroxy-5-nitrobenzaldehyde phenylthiosemicarbazide showed favorable safety profiles, and mice treated with the target compound did not show any symptoms of general toxicity following a single dose of 500 mg/kg. In the allopurinol group, 50 % of the mice died. These results provide a structural framework and mechanism of XOD inhibition that may facilitate the design of hyperuricemia and gout treatments.

Effects of allopurinol and febuxostat on uric acid transport and transporter expression in human umbilical vein endothelial cells

Uric acid induces radical oxygen species formation, endothelial inflammation, and endothelial dysfunction which contributes to the progression of atherosclerosis. Febuxostat inhibits BCRP- and allopurinol stimulates MRP4-mediated uric acid efflux in human embryonic kidney cells. We hypothesized that endothelial cells express uric acid transporters that regulate intracellular uric acid concentration and that modulation of these transporters by febuxostat and allopurinol contributes to their different impact on cardiovascular mortality. The aim of this study was to explore a potential difference between the effect of febuxostat and allopurinol on uric acid uptake by human umbilical vein endothelial cells. Febuxostat increased intracellular uric acid concentrations compared with control. In contrast, allopurinol did not affect intracellular uric acid concentration. In line with this observation, febuxostat increased mRNA expression of GLUT9 and reduced MRP4 expression, while allopurinol did not affect mRNA expression of these uric acid transporters. These findings provide a possible pathophysiological pathway which could explain the higher cardiovascular mortality for febuxostat compared to allopurinol but should be explored further.

Xanthoceras sorbifolium leaves alleviate hyperuricemic nephropathy by inhibiting the PI3K/AKT signaling pathway to regulate uric acid transport

ETHNOPHARMACOLOGICAL RELEVANCE

In China, Xanthoceras sorbifolium Bunge was first documented as "Wen Guan Hua" in the "Jiu Huang Ben Cao" in 1406 A.D. According to the "National Compilation of Chinese Herbal Medicine," X. sorbifolium leaves are sweet and flat in nature and can dispel wind and dampness, suggesting that their extract can be used to treat rheumatoid arthritis. X. sorbifolium Bunge has also been used to treat arteriosclerosis, hyperlipidemia, hypertension, chronic hepatitis, and rheumatism, complications associated with hyperuricemic nephropathy (HN), a condition characterized by kidney damage resulting from high levels of uric acid (UA) in the blood.

AIM OF THE STUDY

The purpose of this study was to investigate the effects and underlying mechanisms of a 70% ethanol extract from X. sorbifolium leaves (EX) in alleviating HN.

MATERIALS AND METHODS

A mouse model of hyperuricemia was established to initially evaluate the hypouricemic effects and determine the effective dose of EX. Phytochemical analyses were conducted using ultra high-performance liquid chromatography and liquid chromatography-mass spectroscopy. The potential key pathways of EX in the alleviation of HN were inferred using network pharmacology and bioinformatics. An HN rat model was then established, and experiments including biomarker detection, western blotting, reverse transcription quantitative polymerase chain reaction, immunohistochemical and Masson's trichrome staining, and transmission electron microscopy were conducted to evaluate the effect of EX on UA transporter expression in vitro.

RESULTS

Network pharmacology and bioinformatics analyses revealed that the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway was the key pathway for the alleviation of HN progression by EX. EX treatment reduced serum biomarkers in HN rats, downregulated the expression of p-PI3K, p-AKT, glucose transporter 9 (GLUT9), urate transporter 1 (URAT1), Collagen I, matrix metalloproteinase (MMP)-2, and MMP-9, and upregulated the expression of ATP binding cassette subfamily G member 2 (ABCG2) to improve renal interstitial fibrosis in HN rats. A high content of both quercitrin and cynaroside were identified in EX; their administration inhibited the increased expression of GLUT9 and URAT1 in damaged HK-2 cells.

CONCLUSION

Our study provides evidence that EX alleviates HN. The potential mechanism underlying this effect may be the regulation of UA transporters, such as GLUT9 and URAT1, by limiting the activation of the PI3K/AKT signaling pathway to improve renal injury.

Impacts of Febuxostat on Cerebral and Cardiovascular Events in Elderly Patients with Hyperuricemia: Post Hoc Analysis of a Randomized Controlled Trial

A recent meta-analysis found no benefit of uric acid-lowering therapy including febuxostat on death, cardiovascular events, or renal impairment. However, there may be populations that benefit from febuxostat in reducing mortality and cerebral and cardiovascular events. The aim of the present study was to examine the clinical benefit of febuxostat in elderly patients stratified by age using Febuxostat for Cerebral and CaRdiorenovascular Events PrEvEntion StuDy (FREED) data. FREED was a randomized study involving patients aged 65 years or older with hyperuricemia and risk factors for cerebral, cardiovascular, or renal diseases. A total of 1,070 patients were included in this post hoc analysis, divided into 2 age groups: 65-74 years and ≥ 75 years. Patients were randomized into febuxostat and non-febuxostat groups, with uric acid levels monitored for 36 months. The primary composite end point included cerebral, cardiovascular, and renal events. In patients aged between 65 and 74 years, febuxostat significantly reduced the risk of future cerebral and cardiorenovascular events. However, no effects of febuxostat were found in the older population aged ≥ 75 years. Heterogeneity in potential interactions between the age and febuxostat treatment was particularly observed in non-fatal cerebral and cardiovascular events and all-cause death. Patients aged ≥ 75 years exhibited more pre-existing factors associated with cerebral and cardiorenovascular events than those aged 65-74 years. The effectiveness of febuxostat varies by age group, with potential benefits for patients aged 65-74 years. The effects of febuxostat are complex and it is important to consider patient characteristics in its clinical use.

Analyzing chemical composition of Sargentodoxae caulis water extract and their hypouricemia effect in hyperuricemic mice

Hyperuricemia (HUA) is a metabolic disease characterized by the increase of serum uric acid (UA) level. Sargentodoxae Caulis (SC) is a commonly used herbal medicine for the treatment of gouty arthritis, traumatic swelling, and rheumatic arthritis in clinic. In this study, a total of fifteen compounds were identified in SC water extract using UHPLC-Q-TOF-MS/MS, including three phenolic acids, seven phenolic glycosides, four organic acids, and one lignan. Then, to study the hypouricemia effect of SC, a HUA mouse model was induced using a combination of PO, HX, and 20% yeast feed. After 14 days of treatment with the SC water extract, the levels of serum UA, creatinine (CRE), blood urea nitrogen (BUN) were reduced significantly, and the organ indexes were restored, the xanthine oxidase (XOD) activity were inhibited as well. Meanwhile, SC water extract could ameliorate the pathological status of kidneys and intestine of HUA mice. Additionally, quantitative real-time PCR (qRT-PCR) and western blotting results showed that SC water extract could increase the expression of ATP binding cassette subfamily G member 2 (ABCG2), organic cation transporter 1 (OCT1), organic anion transporter 1 (OAT1) and organic anion transporter 3 (OAT3), whereas decrease the expression of glucose transporter 9 (GLUT9). This study provided a data support for the clinical application of SC in the treatment of HUA.

Comparative Risk of Gout Flares When Initiating or Escalating Various Urate-Lowering Therapy: A Systematic Review With Network Meta-Analysis

OBJECTIVE

We systematically examined comparative gout flare risk after initiation or escalation of different urate-lowering therapies (ULTs), comparative flare risk with and without concomitant flare prophylaxis, adverse event rates associated with flare prophylaxis, and optimal duration of flare prophylaxis.

METHODS

We searched the Medline, Embase, Web of Science, and Cochrane databases and clinical trial registries from inception to November 2021 for trials investigating adults with gout initiating or escalating ULT. We performed random effects network meta-analyses and calculated risk ratios (RRs) between treatments. Bias was assessed using the revised Cochrane risk-of-bias tool.

RESULTS

We identified 3,775 records, of which 29 publications (27 trials) were included. When compared to placebo plus prophylaxis, the RR of flares ranged from 1.08 (95% confidence interval [CI] 0.87-1.33) for febuxostat 40 mg plus prophylaxis to RR 2.65 [95% CI 1.58-4.45] for febuxostat 80 mg plus lesinurad 400 mg plus prophylaxis. Compared to ULT alone, the RR of flares was lower for ULT plus rilonacept 160 mg (RR 0.35 [95% CI 0.25-0.50]), ULT plus rilonacept 80 mg (RR 0.43 [95% CI 0.31-0.60]) and ULT plus colchicine (RR 0.50 [95% CI 0.35-0.72]). There was limited evidence for other flare prophylaxis and on prophylaxis harms and optimal duration. Primarily because of missing outcome data and bias in the selection of reported results, 71.4% and 63.4% of studies were assessed as high risk of bias for flares and adverse events, respectively.

CONCLUSION

The RR of flares when introducing ULT varies depending on ULT drug and dosing strategies. There were limited data on ULT escalation. Flare prophylaxis with colchicine and rilonacept reduces flare incidence. More research is required on the harms and optimal duration of prophylaxis.

Empagliflozin and Risk of Incident Gout: Analysis from the EMPagliflozin Comparative Effectiveness and SafEty (EMPRISE) Cohort Study

BACKGROUND

Hyperuricemia is frequently observed in patients with type 2 diabetes (T2D) and is associated with increased risk of gout and cardiovascular disease (CVD). Empagliflozin lowers serum urate levels by enhancing its urinary excretion.

OBJECTIVE

To compare initiators of empagliflozin vs dipeptidyl peptidase-4 inhibitor (DPP4i) and initiators of empagliflozin vs glucagon-like peptide-1 receptor agonist (GLP-1RA) with respect to the risk of incident gout events.

DESIGN AND PARTICIPANTS

Using three claims-based datasets from 08/2014 to 09/2019, we generated two cohorts (cohort 1: empagliflozin vs DPP4i; cohort 2: empagliflozin vs GLP-1RA) of adult patients with T2D and without prior history of gout or gout-specific medication dispensing separately in each dataset. To assess the risk of incident gout, we estimated hazard ratios (HR) and rate differences (RD) per 1000 person-years (PY) with their 95% confidence intervals (CI) before and after 1:1 propensity score (PS) matching adjusting for 141 baseline covariates.

KEY RESULTS

We identified 102,262 pairs of 1:1 propensity score-matched adults in cohort 1 and 131,216 pairs in cohort 2. Over a mean follow-up period of 8 months on treatment, the risk of gout was lower in patients initiating empagliflozin compared to DPP4i (HR = 0.69: 95% CI (0.60-0.79); RD =  - 2.27: 95% CI (- 3.08, 1.46)) or GLP-1RA (HR = 0.83: 95% CI (0.73-0.94); RD =  - 0.99: 95% CI (- 1.66, - 0.32)). Results were consistent across subgroups (sex, age, body mass index, chronic kidney disease, heart failure, cardiovascular disease, and concurrent diuretic use) and sensitivity analyses.

CONCLUSIONS

Among adults with T2D, the initiation of empagliflozin vs a DPP4i or GLP-1RA was associated with lower risk of incident gout, complementing results from a post hoc analysis of the EMPA-REG OUTCOME trial and previously published observational research focusing on the sodium-glucose co-transporter-2 inhibitor class in more narrowly defined study populations.

Design, synthesis, and biological evaluation of 3-phenyl substituted pyridine derivatives as potential dual inhibitors of XOR and URAT1

Xanthine oxidoreductase (XOR) and uric acid transporter 1 (URAT1) are two most widely studied targets involved in production and reabsorption of uric acid, respectively. Marketed drugs almost target XOR or URAT1, but sometimes, single agents might not achieve aim of lowering uric acid to ideal value in clinic. Thus, therapeutic strategies of combining XOR inhibitors with uricosuric drugs were proposed and implemented. Based on our initial work of virtual screening, A and B were potential hits for dual-targeted inhibitors on XOR/URAT1. By docking A/B with XOR/URAT1 respectively, compounds I1-7 were designed to get different degree of inhibition effect on XOR and URAT1, and I7 showed the best inhibitory effect on XOR (IC50 = 0.037 ± 0.001 μM) and URAT1 (IC50 = 546.70 ± 32.60 μM). Further docking research on I7 with XOR/URAT1 led to the design of compounds II with the significantly improved inhibitory activity on XOR and URAT1, such as II11 and II15. Especially, for II15, the IC50 of XOR is 0.006 ± 0.000 μM, superior to that of febuxostat (IC50 = 0.008 ± 0.000 μM), IC50 of URAT1 is 12.90 ± 2.30 μM, superior to that of benzbromarone (IC50 = 27.04 ± 2.55 μM). In acute hyperuricemia mouse model, II15 showed significant uric acid lowering effect. The results suggest that II15 had good inhibitory effect on XOR/URAT1, with the possibility for further investigation in in-vivo models of hyperuricemia.

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.

Combination Treatment with Verinurad and Allopurinol in CKD: A Randomized Placebo and Active Controlled Trial

Key Points

The SAPPHIRE trial was designed to assess albuminuria-lowering effects of the urate transporter 1 inhibitor verinurad combined with allopurinol in patients with CKD. Verinurad 3, 7.5, and 12 mg in combination with allopurinol 300 mg did not reduce albuminuria during 34 weeks treatment compared with allopurinol alone or placebo. Verinurad/allopurinol combination dose-dependently reduced serum urate concentrations compared with placebo.

Background

Hyperuricemia is associated with elevated risks of cardiovascular and chronic kidney disease (CKD). Since inhibition of urate transporter 1 has been suggested to be potentially nephroprotective, we performed a phase 2b study to assess albuminuria-lowering effects of the urate transporter 1 inhibitor verinurad combined with the xanthine oxidase inhibitor allopurinol in patients with CKD and hyperuricemia.

Methods

In this randomized placebo and active controlled trial, we enrolled participants with serum urate concentrations ≥6.0 mg/dl, eGFR ≥25 ml/min per 1.73 m2, and a urinary albumin-creatinine ratio (UACR) 30–5000 mg/g to one of five treatment arms: placebo, placebo+allopurinol 300 mg/day, verinurad 3 mg+allopurinol 300 mg/day, verinurad 7.5 mg+allopurinol 300 mg/day, or verinurad 12 mg+allopurinol 300 mg/day in a 1:1:1:1:1 ratio. The primary end point was the change in UACR from baseline to 34 weeks. Secondary end points were changes from baseline in UACR at week 60 and changes in serum urate and eGFR at weeks 34 and 60.

Results

Between August 2019 and November 2021, 861 adults with CKD (mean age 65 years, 33.0% female, mean eGFR 48 ml/min per 1.73 m2, median UACR 217 mg/g) were enrolled. At 34 weeks, the geometric mean percentage change in UACR from baseline did not differ among treatment groups (16.7%, 95% confidence interval [CI], −0.6 to 37.1 in the 3 mg group, 15.0% [95% CI, −1.85 to 34.6] in the 7.5 mg group, 14.0% [95% CI, −3.4 to 34.4] in the 12 mg group versus 9.9% [95% CI, −6.6 to 29.4] in the allopurinol group, and 37.3% [95% CI, 16.6 to 61.8] in the placebo group). UACR and eGFR change from baseline did not differ among treatment groups after 60 weeks. Verinurad/allopurinol combination dose-dependently reduced serum urate concentrations compared with placebo. The proportion of patients with adverse events and serious adverse events was balanced among treatment groups.

Conclusions

Verinurad in combination with allopurinol did not decrease UACR or eGFR decline, but further reduced serum urate compared with allopurinol alone or placebo.

Clinical Trial registry name and registration number:

SAPPHIRE Trial registration number, NCT03990363 .

Lacticaseibacillus paracasei JS-3 Isolated from "Jiangshui" Ameliorates Hyperuricemia by Regulating Gut Microbiota and iTS Metabolism

Background: A diet high in purines can impair the function of the gut microbiota and disrupt purine metabolism, which is closely associated with the onset of hyperuricemia. Dietary regulation and intestinal health maintenance are key approaches for controlling uric acid (UA) levels. Investigating the impacts of fermented foods offers potential dietary interventions for managing hyperuricemia. Methods: In this study, we isolated a strain with potent UA-degrading capabilities from "Jiangshui", a fermented food product from Gansu, China. We performed strain identification and assessed its probiotic potential. Hyperuricemic quails, induced by a high-purine diet, were used to assess the UA degradation capability of strain JS-3 by measuring UA levels in serum and feces. Additionally, the UA degradation pathways were elucidated through analyses of the gut microbiome and fecal metabolomics. Results: JS-3, identified as Lacticaseibacillus paracasei, was capable of eliminating 16.11% of uric acid (UA) within 72 h, rapidly proliferating and producing acid within 12 h, and surviving in the gastrointestinal tract. Using hyperuricemic quail models, we assessed JS-3's UA degradation capacity. Two weeks after the administration of JS-3 (2 × 108 cfu/d per quail), serum uric acid (SUA) levels significantly decreased to normal levels, and renal damage in quails was markedly improved. Concurrently, feces from the JS-3 group demonstrated a significant degradation of UA, achieving up to 49% within 24 h. 16S rRNA sequencing revealed JS-3's role in gut microbiota restoration by augmenting the probiotic community (Bifidobacterium, Bacteroides unclassified_f-Lachnospiraceae, and norank_fynorank_o-Clostridia_UCG-014) and diminishing the pathogenic bacteria (Macrococus and Lactococcus). Corresponding with the rise in short-chain fatty acid (SCFA)-producing bacteria, JS-3 significantly increased SCFA levels (p < 0.05, 0.01). Additionally, JS-3 ameliorated metabolic disturbances in hyperuricemic quails, influencing 26 abnormal metabolites predominantly linked to purine, tryptophan, and bile acid metabolism, thereby enhancing UA degradation and renal protection. Conclusions: For the first time, we isolated and identified an active probiotic strain, JS-3, from the "Jiangshui" in Gansu, used for the treatment of hyperuricemia. It modulates host-microbiome interactions, impacts the metabolome, enhances intestinal UA degradation, reduces levels of SUA and fecal UA, alleviates renal damage, and effectively treats hyperuricemia without causing gastrointestinal damage. In summary, JS-3 can serve as a probiotic with potential therapeutic value for the treatment of hyperuricemia.

Timing of Initiation of Xanthine Oxidase Inhibitors Based on Serum Uric Acid Level Does Not Predict Renoprognosis in Patients with Preserved Kidney Function

Background: Despite recent evidence of remaining possibility that early initiation of xanthine oxidase inhibitors (XOIs) is beneficial in renoprognosis for patients with stage 2 or less chronic kidney disease (CKD), no evidence is available regarding the difference in renoprognosis based on serum uric acid (sUA) levels at the initiation of XOIs among patients with preserved kidney function. Methods: New XOI initiators were divided into quartiles based on baseline sUA. Primary outcome was the composite incidence of a significant estimated glomerular filtration rate (eGFR) decline (≥40% decline in eGFR from baseline or development of eGFR <30 mL/1.73 m2/min) or all-cause death within 5 years. Results: After excluding inapplicable patients, 1170 XOI initiators were analyzed (mean ± standard deviation age: 68 ± 14.3 years; sUA: 10.6 ± 1.15 mg/dL). On overall median [interquartile range (IQR)] follow-up of 824 (342, 1576) days, incidence rate of the primary outcome was 287 per 1000 person-years for 5 years. Although the nonadjusted model showed a dose-response association between baseline sUA level and the outcome, the adjusted model showed no significant association. Adjusted hazard ratios (95% confidence interval) of the second, third, and fourth quartiles of baseline sUA with the composite outcome within 5 years compared to the first quartile were 1.00 (0.78, 1.29), 1.00 (0.80, 1.30), and 1.02 (0.80, 1.32), respectively. Conclusions: Early initiation of XOIs did not predict a significant benefit on renoprognosis even among the population with preserved kidney function. The validity of initiating XOIs with the aim of improving renoprognosis based on sUA is questionable.

Discovery of 2,8-dihydroxyadenine in HUA patients with uroliths and biomarkers for its associated nephropathy

Currently, it is acknowledged that gout is caused by uric acid (UA). However, some studies have revealed no correlation between gout and UA levels, and growing evidence suggests that 2,8-dihydroxyadenine (2,8-DHA), whose structural formula is similar to UA but is less soluble, may induce gout. Hence, we hypothesized that uroliths from hyperuricemia (HUA) patients, which is closely associated with gout, may contain 2,8-DHA. In this study, 2,8-DHA in uroliths and serum of HUA patients were determined using HPLC. Moreover, bioinformatics was used to investigate the pathogenic mechanisms of 2,8-DHA nephropathy. Subsequently, a mouse model of 2,8-DHA nephropathy established by the gavage administration of adenine, as well as a model of injured HK-2 cells induced by 2,8-DHA were used to explore the pathogenesis of 2,8-DHA nephropathy. Interestingly, 2,8-DHA could readily deposit in the cortex of the renal tubules, and was found in the majority of these HUA patients. Additionally, the differentially expressed genes between 2,8-DHA nephropathy mice and control mice were found to be involved in inflammatory reactions. Importantly, CCL2 and IL-1β genes had the maximum degree, closeness, and betweenness centrality scores. The expressions of CCL2 and IL-1β genes were significantly increased in the serum of 24 HUA patients with uroliths, indicating that they may be significant factors for 2,8-DHA nephropathy. Further analysis illustrated that oxidative damage and inflammation were the crucial processes of 2,8-DHA renal injury, and CCL2 and IL-1β genes were verified to be essential biomarkers for 2,8-DHA nephropathy. These findings revealed further insights into 2,8-DHA nephropathy, and provided new ideas for its diagnosis and treatment.

The Effects of Pharmacological Urate-Lowering Therapy on Cardiovascular Disease in Older Adults with Gout

Cardiovascular disease is an important cause of mortality in older patients. In addition to the traditional risk factors for cardiovascular disease, hyperuricemia has been increasingly associated with an elevated risk of cardiovascular disease. Uric acid itself has several unfavorable effects on the cardiovascular system, and hyperuricemia can lead to the development of gout. Gout is the most prevalent inflammatory rheumatic disease. Older patients with gout have an increased risk of cardiovascular morbidity and mortality due to an increased prevalence of traditional risk factors, as well as the inflammatory burden of gout activity. As the prevalence of traditional risk factors and the prevalence of both hyperuricemia and gout are increasing in older adults, cardiovascular risk management in these patients is very important. This risk management consists of, on the one hand, treatment of individual traditional risk factors and, on the other hand, of urate lowering, thereby decreasing inflammatory burden of gout. However, there is insufficient evidence to conclude that urate-lowering therapy reduces the risk of cardiovascular events. Moreover, from a cardiovascular point of view, there is no preference for one urate lowering drug over another in patients with gout, nor is there enough evidence to support a preference in patients with gout with increased cardiovascular risk. Personalized treatment in older patients with gout should be aimed at optimizing serum uric acid levels, as well as targeting traditional cardiovascular risk factors. Further prospective randomized trials are needed to support the hypothesis that urate lowering reduces cardiovascular risk in older patients with gout.

The clinical benefits of sodium-glucose cotransporter type 2 inhibitors in people with gout

Gout is the most common form of inflammatory arthritis worldwide and is characterized by painful recurrent flares of inflammatory arthritis that are associated with a transiently increased risk of adverse cardiovascular events. Furthermore, gout is associated with multiple cardiometabolic-renal comorbidities such as type 2 diabetes, chronic kidney disease and cardiovascular disease. These comorbidities, potentially combined with gout flare-related inflammation, contribute to persistent premature mortality in gout, independently of serum urate concentrations and traditional cardiovascular risk factors. Although better implementation of standard gout care could improve gout outcomes, deliberate efforts to address the cardiovascular risk in patients with gout are likely to be required to reduce mortality. Sodium-glucose cotransporter type 2 (SGLT2) inhibitors are approved for multiple indications owing to their ability to lower the risk of all-cause and cardiovascular death, hospitalizations for heart failure and chronic kidney disease progression, making them an attractive treatment option for gout. These medications have also been shown to lower serum urate concentrations, the causal culprit in gout risk, and are associated with a reduced risk of incident and recurrent gout, potentially owing to their purported anti-inflammatory effects. Thus, SGLT2 inhibition could simultaneously address both the symptoms of gout and its comorbidities.

Uric acid in health and disease: From physiological functions to pathogenic mechanisms

Owing to renal reabsorption and the loss of uricase activity, uric acid (UA) is strictly maintained at a higher physiological level in humans than in other mammals, which provides a survival advantage during evolution but increases susceptibility to certain diseases such as gout. Although monosodium urate (MSU) crystal precipitation has been detected in different tissues of patients as a trigger for disease, the pathological role of soluble UA remains controversial due to the lack of causality in the clinical setting. Abnormal elevation or reduction of UA levels has been linked to some of pathological status, also known as U-shaped association, implying that the physiological levels of UA regulated by multiple enzymes and transporters are crucial for the maintenance of health. In addition, the protective potential of UA has also been proposed in aging and some diseases. Therefore, the role of UA as a double-edged sword in humans is determined by its physiological or non-physiological levels. In this review, we summarize biosynthesis, membrane transport, and physiological functions of UA. Then, we discuss the pathological involvement of hyperuricemia and hypouricemia as well as the underlying mechanisms by which UA at abnormal levels regulates the onset and progression of diseases. Finally, pharmacological strategies for urate-lowering therapy (ULT) are introduced, and current challenges in UA study and future perspectives are also described.

Inhibition of xanthine oxidase by allopurinol suppresses HMGB1 secretion and ameliorates experimental asthma

BACKGROUND

Extracellular high mobility group box 1 (HMGB1) is a key mediator in driving allergic airway inflammation and contributes to asthma. Yet, mechanism of HMGB1 secretion in asthma is poorly defined. Pulmonary metabolic dysfunction is recently recognized as a driver of respiratory pathology. However, the altered metabolic signatures and the roles of metabolic to allergic airway inflammation remain unclear.

METHODS

Male C57BL/6 J mice were sensitized and challenged with toluene diisocyanate (TDI) to generate a chemically induced asthma model. Pulmonary untargeted metabolomics was employed. According to results, mice were orally administered allopurinol, a xanthine oxidase (XO) inhibitor. Human bronchial epithelial cells (16HBE) were stimulated by TDI-human serum albumin (HSA).

RESULTS

We identified the purine metabolism was the most enriched pathway in TDI-exposed lungs, corresponding to the increase of xanthine and uric acid, products of purine degradation mediated by XO. Inhibition of XO by allopurinol ameliorates TDI-induced oxidative stress and DNA damage, mixed granulocytic airway inflammation and Th1, Th2 and Th17 immunology as well as HMGB1 acetylation and secretion. Mechanistically, HMGB1 acetylation was caused by decreased activation of the NAD+-sirtuin 1 (SIRT1) axis triggered by hyperactivation of the DNA damage sensor poly (ADP-ribose)-polymerase 1 (PARP-1). This was rescued by allopurinol, PARP-1 inhibitor or supplementation with NAD+ precursor in a SIRT1-dependent manner. Meanwhile, allopurinol attenuated Nrf2 defect due to SIRT1 inactivation to help ROS scavenge.

CONCLUSIONS

We demonstrated a novel regulation of HMGB1 acetylation and secretion by purine metabolism that is critical for asthma onset. Allopurinol may have therapeutic potential in patients with asthma.

Impact of Hyperuricemia and Urate-Lowering Agents on Cardiovascular Diseases

The association between hyperuricemia and cardiovascular diseases has been studied for many years. Research has shown a link between high uric acid levels and increased risk of including coronary artery disease hypertension and other cardiovascular conditions. Urate-lowering therapy, particularly with xanthine oxidase inhibitors like allopurinol, has shown promising results in reducing blood pressure in individuals with hyperuricemia and hypertension. Clinical trials and studies have demonstrated significant reductions in both systolic and diastolic blood pressure with urate-lowering treatment. Urate-lowering treatment has shown a favorable effect on reducing systolic blood pressure and major adverse cardiovascular events in patients with previous cardiovascular disease. In terms of cardiovascular safety, clinical trials have indicated that xanthine oxidase inhibitors such as febuxostat are non-inferior to allopurinol and do not increase the risk of death or serious adverse events. Overall, these findings highlight the importance of managing hyperuricemia and utilizing urate-lowering therapy to mitigate the adverse cardiovascular effects associated with elevated uric acid levels.

Targeting Neutrophil Extracellular Traps in Gouty Arthritis: Insights into Pathogenesis and Therapeutic Potential

Gouty arthritis (GA) is an immune-mediated disorder characterized by severe inflammation due to the deposition of monosodium urate (MSU) crystals in the joints. The pathophysiological mechanisms of GA are not yet fully understood, and therefore, the identification of effective therapeutic targets is of paramount importance. Neutrophil extracellular traps (NETs), an intricate structure of DNA scaffold, encompassing myeloperoxidase, histones, and elastases - have gained significant attention as a prospective therapeutic target for gouty arthritis, due to their innate antimicrobial and immunomodulatory properties. Hence, exploring the therapeutic potential of NETs in gouty arthritis remains an enticing avenue for further investigation. During the process of gouty arthritis, the formation of NETs triggers the release of inflammatory cytokines, thereby contributing to the inflammatory response, while MSU crystals and cytokines are sequestered and degraded by the aggregation of NETs. Here, we provide a concise summary of the inflammatory processes underlying the initiation and resolution of gouty arthritis mediated by NETs. Furthermore, this review presents an overview of the current pharmacological approaches for treating gouty arthritis and summarizes the potential of natural and synthetic product-based inhibitors that target NET formation as novel therapeutic options, alongside elucidating the intrinsic challenges of these inhibitors in NETs research. Lastly, the limitations of HL-60 cell as a suitable substitute of neutrophils in NETs research are summarized and discussed. Series of recommendations are provided, strategically oriented towards guiding future investigations to effectively address these concerns. These findings will contribute to an enhanced comprehension of the interplay between NETs and GA, facilitating the proposition of innovative therapeutic strategies and novel approaches for the management of GA.

Cardiovascular Safety of Febuxostat in Patients With Gout or Hyperuricemia: A Systematic Review of Randomized Controlled Trials

INTRODUCTION

To this date, a causal relationship between febuxostat and cardiovascular disease remains controversial as comparison between trials can be challenging and may lead to misleading conclusions, especially when facing heterogeneous cardiovascular outcomes. We aimed to compare the cardiovascular outcomes in the most pertinent trials of febuxostat compared with controls.

METHODS

We searched electronic databases using a PICOS-style approach search strategy of randomized controlled trials (RCTs) on cardiovascular outcomes of febuxostat in patients with gout or hyperuricemia. We conducted a quality and risk of bias assessment of the included clinical trials. The definition of major adverse cardiovascular event as well as all reported cardiovascular outcomes were retrieved from every involved trial.

RESULTS

Of the 1173 records identified from all sources, 20 RCTs were included in the analysis. The mean duration of follow-up was 69.7 ± 81.5 weeks, and febuxostat dose ranged from 10 to 240 mg with 80 mg being the most commonly used dosage. Overall, the quality of evidence deriving from all RCTs showed concerns in most studies (65%). Major adverse cardiovascular event was defined in 7 of the 20 RCTs (35%), and cardiovascular outcome reporting was very heterogeneous. Overall, the data of cardiovascular safety of febuxostat were reassuring.

CONCLUSIONS

Our systematic review showed high level of concerns in quality assessment domains as well heterogeneous cardiovascular outcomes across included studies. Cardiovascular outcomes in the majority of White males with gout treated with febuxostat were reassuring when compared with allopurinol. Further studies are needed to draw conclusions in patients with severe cardiovascular disease.

Urate-Lowering Drugs and Muscle Injury: A Systematic Review and Network Meta-Analysis

Several urate-lowering drugs have been linked to muscle injury. This study investigated the association of oral urate-lowering drugs with the risk of muscle injury by performing a network meta-analysis of randomized and non-randomized controlled trials. A systematic search of MEDLINE, via PubMed, the ClinicalTrials.gov website, and the Cochrane Central Register of Controlled Trials was conducted to identify relevant studies with a primary outcome of "all muscle injuries." A random-effects model was used to perform a frequentist network meta-analysis to estimate whether there was significant heterogeneity among the studies. In total, 32 studies including 28,327 participants with 2694 (9.5%) "all muscle injuries" were assessed, and the overall risk of bias was judged to be low to moderate. No statistically significant differences were found between placebo and 6 urate-lowering therapies: allopurinol (risk ratio, RR, 1.05; 95% confidence interval, 95%CI, 0.63-1.73), febuxostat (RR 1.10, 95%CI 0.71-1.70), lesinurad (RR 7.00, 95%CI 0.31-160.36), lesinurad concomitant with allopurinol (RR 0.85, 95%CI 0.34-2.11), lesinurad concomitant with febuxostat (RR 1.97, 95%CI 0.55-7.03), and topiroxostat (RR 0.99, 95%CI 0.37-2.65). The findings suggest that there is little need to consider the risk of muscle injury when using urate-lowering drugs in the clinical setting.

Allopurinol and cardiovascular outcomes in patients with ischaemic heart disease: the ALL-HEART RCT and economic evaluation

Background

Allopurinol is a xanthine oxidase inhibitor that lowers serum uric acid and is used to prevent acute gout flares in patients with gout. Observational and small interventional studies have suggested beneficial cardiovascular effects of allopurinol.

Objective

To determine whether allopurinol improves major cardiovascular outcomes in patients with ischaemic heart disease.

Design

Prospective, randomised, open-label, blinded endpoint multicentre clinical trial.

Setting

Four hundred and twenty-four UK primary care practices.

Participants

Aged 60 years and over with ischaemic heart disease but no gout.

Interventions

Participants were randomised (1 : 1) using a central web-based randomisation system to receive allopurinol up to 600 mg daily that was added to usual care or to continue usual care.

Main outcome measures

The primary outcome was the composite of non-fatal myocardial infarction, non-fatal stroke or cardiovascular death. Secondary outcomes were non-fatal myocardial infarction, non-fatal stroke, cardiovascular death, all-cause mortality, hospitalisation for heart failure, hospitalisation for acute coronary syndrome, coronary revascularisation, hospitalisation for acute coronary syndrome or coronary revascularisation, all cardiovascular hospitalisations, quality of life and cost-effectiveness. The hazard ratio (allopurinol vs. usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis.

Results

From 7 February 2014 to 2 October 2017, 5937 participants were enrolled and randomised to the allopurinol arm (n = 2979) or the usual care arm (n = 2958). A total of 5721 randomised participants (2853 allopurinol; 2868 usual care) were included in the modified intention-to-treat analysis population (mean age 72.0 years; 75.5% male). There was no difference between the allopurinol and usual care arms in the primary endpoint, 314 (11.0%) participants in the allopurinol arm (2.47 events per 100 patient-years) and 325 (11.3%) in the usual care arm (2.37 events per 100 patient-years), hazard ratio 1.04 (95% confidence interval 0.89 to 1.21); p = 0.65. Two hundred and eighty-eight (10.1%) participants in the allopurinol arm and 303 (10.6%) participants in the usual care arm died, hazard ratio 1.02 (95% confidence interval 0.87 to 1.20); p = 0.77. The pre-specified health economic analysis plan was to perform a 'within trial' cost-utility analysis if there was no statistically significant difference in the primary endpoint, so NHS costs and quality-adjusted life-years were estimated over a 5-year period. The difference in costs between treatment arms was +£115 higher for allopurinol (95% confidence interval £17 to £210) with no difference in quality-adjusted life-years (95% confidence interval -0.061 to +0.060). We conclude that there is no evidence that allopurinol used in line with the study protocol is cost-effective.

Limitations

The results may not be generalisable to younger populations, other ethnic groups or patients with more acute ischaemic heart disease. One thousand six hundred and thirty-seven participants (57.4%) in the allopurinol arm withdrew from randomised treatment, but an on-treatment analysis gave similar results to the main analysis.

Conclusions

The ALL-HEART study showed that treatment with allopurinol 600 mg daily did not improve cardiovascular outcomes compared to usual care in patients with ischaemic heart disease. We conclude that allopurinol should not be recommended for the secondary prevention of cardiovascular events in patients with ischaemic heart disease but no gout.

Future work

The effects of allopurinol on cardiovascular outcomes in patients with ischaemic heart disease and co-existing hyperuricaemia or clinical gout could be explored in future studies.

Trial registration

This trial is registered as EU Clinical Trials Register (EudraCT 2013-003559-39) and ISRCTN (ISRCTN 32017426).

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 11/36/41) and is published in full in Health Technology Assessment; Vol. 28, No. 18. See the NIHR Funding and Awards website for further award information.

Cardiovascular safety of febuxostat versus allopurinol among the Asian patients with or without gout: A systematic review and meta-analysis

The cardiovascular (CV) safety of febuxostat compared to allopurinol for the treatment of hyperuricemia among Asian patients is uncertain. In this study, we conducted a systematic review and meta-analysis to compare the CV safety profiles of febuxostat with allopurinol in Asian patients with hyperuricemia. A total of 13 studies were included. On the basis of the pooled results of cohort studies, febuxostat users were at a significantly higher risk for acute coronary syndrome (ACS; hazard ratio [HR]: 1.06, 95% confidence interval [CI]: 1.03-1.09, p < 0.01), atrial fibrillation (HR: 1.19, 95% CI: 1.05-1.35, p < 0.01) than allopurinol users, whereas no significant difference between febuxostat and allopurinol existed for urgent coronary revascularization (HR: 1.07, 95% CI: 0.98-1.16, p = 0.13), and stroke (HR: 0.96, 95% CI: 0.91-1.01, p = 0.13). Nevertheless, that difference in results of acute decompensated heart failure (ADHF; HR: 0.73, 95% CI: 0.35-1.53, p = 0.40) and all-cause death (HR = 0.86, 95% CI: 0.49-1.51, p = 0.60) was not significant based on randomized controlled trials. In the Chinese subgroup, febuxostat could increase the risk of ADHF (HR: 1.22, 95% CI: 1.01-1.48, p < 0.05), CV death (HR: 1.25, 95% CI: 1.03-1.50, p < 0.05), and all-cause mortality (HR: 1.07, 95% CI: 1.01-1.14, p < 0.05) compared to allopurinol. In conclusion, the use of febuxostat, compared with allopurinol among Asian patients, was associated with a significantly increased risk of adverse CV events.

Network pharmacology, molecular docking, combined with experimental verification to explore the role and mechanism of shizhifang decoction in the treatment of hyperuricemia

Ethnopharmacological relevance

Shizhifang Decoction, a traditional Chinese medicine prescription formulated by Professor Zheng Pingdong of Shuguang Hospital, has been widely utilized in clinical settings for the treatment of hyperuricemia due to its proven safety and efficacy.

Objective

In this study, we used network pharmacology, molecular docking technology, and experimental validation to elucidate the therapeutic effects and underlying mechanisms of Shizhifang Decoction in managing hyperuricemia.

Methods

Quality control and component identification of the freeze-dried powder of Shizhifang Decoction were conducted using ultra-high performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry. Active ingredients and their corresponding targets were obtained from Traditional Chinese Medicine Systems Pharmacology, Traditional Chinese Medicine Information Database, The Encyclopedia of Traditional Chinese Medicine, and other databases. Disease-related targets for hyperuricemia were collected from GeneCards and DisGeNET databases. The Venny platform is used to screen common targets for drug active ingredients and diseases. Subsequently, we constructed an active component-target-disease interaction network using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, create a component disease common target network using Cytoscape 3.9.1 software, from which core targets were selected. Import common targets into the Database for Annotation, Visualization and Integrated Discovery (DAVID) for Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analysis. Molecular docking was then conducted to validate the binding capacity of key active ingredients and their associated targets in Shizhifang Decoction. The theoretical predictions were further confirmed through in vitro and in vivo experiments.

Result

A total of 35 active ingredients and 597 action targets were identified, resulting in 890 disease-related targets for hyperuricemia. After comprehensive analysis, 99 common targets were determined. Protein-protein interaction network analysis revealed crucial relationships between these targets and hyperuricemia. Among them, 12 core targets (CASP3, IL1B, IL6, TNF, TP53, GAPDH, PTGS2, MYC, INS, VEGFA, ESR1, PPARG) were identified. Gene Ontology enrichment analysis demonstrated significant associations with the regulation of inflammatory response, cell apoptosis, and the positive regulation of extracellular regulated protein kinases 1 and extracellular regulated protein kinases 2 cascades. Kyoto Encyclopedia of Genes and Genomes pathway analysis highlighted inflammation and apoptosis-related pathways as critical mediators of Shizhifang Decoction's effects on hyperuricemia. Molecular docking studies further supported the interactions between apoptosis-related proteins and active ingredients in the extracellular regulated protein kinases 1/2 signaling pathway. In vitro experiments confirmed the downregulation of apoptosis-related proteins (caspase-3, Bax, Bcl-2) and the inhibition of the extracellular regulated protein kinases 1/2 signaling pathway by Shizhifang Decoction. These findings were also validated in animal models, demonstrating the potential of Shizhifang Decoction to mitigate renal injury induced by hyperuricemia through extracellular regulated protein kinases 1/2-mediated inhibition of renal tubular epithelial cell apoptosis.

Conclusion

Our study provides valuable insights into the main mechanism by which Shizhifang Decoction ameliorates hyperuricemia. By targeting the ERK1/2 signaling pathway and modulating cell apoptosis, Shizhifang Decoction exhibits promising therapeutic potential for the treatment of hyperuricemia. These findings support the continued exploration and development of Shizhifang Decoction as a potential herbal remedy for hyperuricemia management.

Association between hyperuricemia and long-term mortality in patients with hypertension: results from the NHANES 2001-2018

Objective

The prevalence of hyperuricemia and hypertension is steadily increasing, and these conditions often share common risk factors. This study aimed to investigate the association among hyperuricemia, hypertension, and all-cause mortality in a nationally representative U.S. population.

Methods

Data for 38,644 participants were obtained from the National Health and Nutrition Examination Survey (NHANES) 2001-2018. Hyperuricemia was defined as a serum urate concentration >420 μmol/L in men and >360 μmol/L in women. Information regarding death outcomes was obtained through the National Death Index (NDI). Multivariate logistic regression, Cox proportional hazards models, and restricted cubic spline (RCS) analyses were used to evaluate the association between hyperuricemia and hypertension in all included participants, as well as long-term mortality in patients with hypertension.

Results

Among all participants, 6,956 (18.0%) had hyperuricemia, while 31,688 (82.0%) had nonhyperuricemia. According to the adjusted models, hyperuricemia was more strongly associated with hypertension (OR 2.04) than was non-hyperuricemia. During the median follow-up period of 78 months, both hyperuricemia (HR 1.48, 1.95) and hypertension (HR 1.42, 1.69) independently associated with the increased risk of all-cause mortality and cardiovascular mortality, respectively, with the highest risk observed in those with both conditions (HR 1.87, 2.82). RCS analyses revealed nonlinear J-shaped (for hypertension) and U-shaped (for both all-cause and cardiovascular mortality) relationships with serum urate levels.

Conclusions

Hyperuricemia is associated with an elevated risk of developing hypertension compared to non-hyperuricemia. Among patients with hypertension, those with hyperuricemia are more likely to experience all-cause and cardiovascular mortality during long-term follow-up.

[Gout, beyond the joint: How should we treat it?]

Gout is a disease caused by the chronic deposition of monosodium urate crystals. Its clinical presentation as an acute, self-limiting arthritis and the belief that it is a banal, self-inflicted disease have led to its poor management. Despite advances in the knowledge of the disease and the simplicity of its management, no more than 30% of patients are well treated. In Spain, the prevalence of gout is 2.5% and its incidence is increasing. In the following article we will review the pathogenesis of gout and hyperuricaemia, highlighting the greater weight of genetics and renal function over diet. We will look at the consequences of crystal deposition. Gout, in addition to its joint presentation and renal involvement, has been shown to be an independent cardiovascular risk factor. Hypouricemic therapy is the most important treatment, as it is the one that dissolves the crystals and cures the disease. This requires the sustained achievement of uricemia levels below 6mg/dl. We will also review preventive and flares treatment, as well as the role of patient education in terms of both lifestyle and dietary habits and adherence to pharmacological treatment.

Plasma and Urinary Metabolomic Analysis of Gout and Asymptomatic Hyperuricemia and Profiling of Potential Biomarkers: A Pilot Study

Gout results from monosodium urate deposition caused by hyperuricemia, but most individuals with hyperuricemia remain asymptomatic. The pathogenesis of gout remains uncertain. To identify potential biomarkers distinguishing gout from asymptomatic hyperuricemia, we conducted a genetic analysis of urate transporters and metabolomic analysis as a proof-of-concept study, including 33 patients with gout and 9 individuals with asymptomatic hyperuricemia. The variant allele frequencies of rs72552713, rs2231142, and rs3733591, which are related to serum urate levels (SUA) and gout, did not differ between the gout and asymptomatic hyperuricemia groups. In metabolomic analysis, the levels of citrate cycle intermediates, especially 2-ketoglutarate, were higher in patients with gout than in those with asymptomatic hyperuricemia (fold difference = 1.415, p = 0.039). The impact on the TCA cycle was further emphasized in high-risk gout (SUA ≥ 9.0 mg/dL). Of note, urinary nicotinate was the most prominent biomarker differentiating high-risk gout from asymptomatic hyperuricemia (fold difference = 6.515, p = 0.020). Although urate transporters play critical roles in SUA elevation and promote hyperuricemia, this study suggests that the progression from asymptomatic hyperuricemia to gout might be closely related to other genetic and/or environmental factors affecting carbohydrate metabolism and urinary urate excretion.

Effects of uric acid on ischemic diseases, stratified by lipid levels: a drug-target, nonlinear Mendelian randomization study

Although uric acid-lowering agents such as xanthine oxidase inhibitors have potential cardioprotective effects, studies on their use in preventing cardiovascular diseases are lacking. We investigated the genetically proxied effects of reducing uric acid on ischemic cardiovascular diseases in a lipid-level-stratified population. We performed drug-target Mendelian randomization (MR) analyses using UK Biobank data to select genetic instruments within a uric acid-lowering gene, xanthine dehydrogenase (XDH), and construct genetic scores. For nonlinear MR analyses, individuals were stratified by lipid level. Outcomes included acute myocardial infarction (AMI), ischemic heart disease, cerebral infarction, transient cerebral ischemic attack, overall ischemic disease, and gout. We included 474,983 non-gout individuals with XDH-associated single-nucleotide polymorphisms. The XDH-variant-induced uric acid reduction was associated with reduced risk of gout (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.78-0.93; P < 0.001), cerebral infarction (OR, 0.86; 95% CI, 0.75-0.98; P = 0.023), AMI (OR, 0.79; 95% CI, 0.66-0.94; P = 0.010) in individuals with triglycerides ≥ 188.00 mg/dL, and cerebral infarction in individuals with low-density lipoprotein cholesterol (LDL-C) ≤ 112.30 mg/dL (OR, 0.76; 95% CI, 0.61-0.96; P = 0.020) or LDL-C of 136.90-157.40 mg/dL (OR, 0.67; 95% CI, 0.49-0.92; P = 0.012). XDH-variant-induced uric acid reduction lowers the risk of gout, AMI for individuals with high triglycerides, and cerebral infarction except for individuals with high LDL-C, highlighting the potential heterogeneity in the protective effects of xanthine oxidase inhibitors for treating AMI and cerebral infarction depending on the lipid profiles.

Hyperuricemia and Gout Reduction by SGLT2 Inhibitors in Diabetes and Heart Failure: JACC Review Topic of the Week

Gout is characterized by increased production of purines (through the pentose phosphate pathway), which is coupled with reduced renal or intestinal excretion of urate. Concurrent upregulation of nutrient surplus signaling (mammalian target of rapamycin and hypoxia-inducible factor-1a) and downregulation of nutrient deprivation signaling (sirtuin-1 and adenosine monophosphate-activated protein kinase) redirects glucose toward anabolic pathways (rather than adenosine triphosphate production), thus promoting heightened oxidative stress and cardiomyocyte and proximal tubular dysfunction, leading to cardiomyopathy and kidney disease. Hyperuricemia is a marker (rather than a driver) of these cellular stresses. By inducing a state of starvation mimicry in a state of nutrient surplus, sodium-glucose cotransporter-2 inhibitors decrease flux through the pentose phosphate pathway (thereby attenuating purine and urate synthesis) while promoting renal urate excretion. These convergent actions exert a meaningful effect to lower serum uric acid by ≈0.6 to 1.5 mg/dL and to reduce the risk of gout by 30% to 50% in large-scale clinical trials.

Xanthine oxidase inhibitors treatment or discontinuation effects on mortality: evidence of xanthine oxidase inhibitors withdrawal syndrome

Objectives: This study investigates the impact of xanthine oxidase inhibitors (XOI) on mortality in patients with cardiovascular diseases. XOI withdrawal has been reported to increased mortality risk due to rapid adenosine triphosphate (ATP) deficiency. This study aims to determine whether XOI treatment reduces mortality and whether XOI withdrawal increases mortality. Methods: This is a real-world database study using the Japanese Registry of All Cardiac and Vascular Diseases (J-ROAD). We analyzed 1,648,891 hospitalized patients aged 20-90 with acute coronary syndrome or heart failure. In the first study, mortality rates were compared between patients without urate-lowering agents (n = 1,292,486) and those with XOI agents (n = 315,388, excluding 41,017 on other urate-lowering agents). In the second study, mortality rates were compared between the XOI continuous medication group (n = 226,261) and the XOI withdrawal group (n = 89,127). Results: After multiple adjustments, XOI treatment group showed significantly lower mortality compared with that without any urate-lowering agent (odds ratio (OR), 0.576, 95% confidence interval (CI), 0.567-0.587, p < .001). In the sub-analysis, the group with allopurinol (OR, 0.578; 95% CI, 0.557-0.600), febuxostat (OR, 0.610; 95% CI, 0.599-0.622), and topiroxostat (HR, 0.545; 95% CI, 0.473-0.628) showed lower OR of mortality compared with that without any urate-lowering agent. XOI withdrawal group led to significantly higher death rates compared to XOI continuous group (19.8% vs. 0.03%; p < .001). Conclusion: XOI treatment for patients with cardiovascular diseases is associated with reduced mortality. Conversely, XOI withdrawal is linked to elevated mortality risk. This emphasizes the importance of both prescribing and discontinuing XOI carefully to optimize patient outcomes.

Traditional Chinese medicine in the treatment of patients with hyperuricemia: A randomized placebo-controlled double-blinded clinical trial

BACKGROUND

Studies have demonstrated the association of hyperuricemia with hypertension, metabolic syndrome, cardiovascular disease, and chronic renal disease. Although Western medicine presents promising effects for treating hyperuricemia and gout, identifying a safe and effective alternative to traditional Chinese medicine (TCM) for treating hyperuricemia is essential.

OBJECTIVE

To evaluate the efficacy and safety of TCM formulas, "Wu-Ling San" and "Yin Chen Wu-Ling San," in patients with hyperuricemia.

METHODS

A randomized, double-blinded, placebo-controlled clinical trial in adults with hyperuricemia was conducted. Sixty patients with serum urate level higher than 8 mg/dL were enrolled in the study. Patients were then randomized into three arms: "Wu-Ling San," "Yin Chen Wu-Ling San," and placebo for 4 weeks. Efficacy and safety were evaluated at weeks 2, 4, and 8. Primary and secondary endpoints were set to evaluate the serum urate concentration and related indicators at weeks 2, 4, and 8.

RESULTS

No significant differences were observed among the three arms in terms of the serum urate level (<6 mg/dL) at week 4. The serum urate level was lower in the "Yin Chen Wi-Ling" arm at week 8 (8.1 mg/dL vs. 9.1 mg/dL, p = .034). The serum urate levels were significantly different in both the "Wu-Ling San" and "Yin Chen Wu-Ling San" arms from those at the baseline (p < .05).

CONCLUSIONS

Two TCM formulas were found to be relatively safe for the short-term treatment of the patients with hyperuricemia. No statistically significant difference was observed in reaching the target-serum urate level <6 mg/dL.

Two cases report of febuxostat-induced acute liver injury: acute heart failure as a probable risk factor?

Drug induced liver injury, as a sub-type of hepatotoxicity, is rare but practical problem, producing challenges for clinicians. Within the recent two months, two patients with heart failure develop febuxostat-induced acute liver injury during hospital stay. To the best of our knowledge, very few cases of febuxostat-induced hepatotoxicity have been reported up to now. In this paper, two unusual cases of febuxostat-induced acute liver injury are herein described. The medical history, drug treatment, clinical symptoms, liver function tests, diagnosis and prognosis are fully given in this paper. It should be noticed that, two liver injury happen in patients of heart failure with reduced ejection fraction. Whether heart failure is a risk factor of febuxostat related liver injury, deserves further research. This paper reminds the clinicians that more attention should be paid to the acute liver injury caused by febuxostat, and liver function tests are suggested especially for patients of heart failure.

Integrated Functions of Cardiac Energetics, Mechanics, and Purine Nucleotide Metabolism

Purine nucleotides play central roles in energy metabolism in the heart. Most fundamentally, the free energy of hydrolysis of the adenine nucleotide adenosine triphosphate (ATP) provides the thermodynamic driving force for numerous cellular processes including the actin-myosin crossbridge cycle. Perturbations to ATP supply and/or demand in the myocardium lead to changes in the homeostatic balance between purine nucleotide synthesis, degradation, and salvage, potentially affecting myocardial energetics and, consequently, myocardial mechanics. Indeed, both acute myocardial ischemia and decompensatory remodeling of the myocardium in heart failure are associated with depletion of myocardial adenine nucleotides and with impaired myocardial mechanical function. Yet there remain gaps in the understanding of mechanistic links between adenine nucleotide degradation and contractile dysfunction in heart disease. The scope of this article is to: (i) review current knowledge of the pathways of purine nucleotide depletion and salvage in acute ischemia and in chronic heart disease; (ii) review hypothesized mechanisms linking myocardial mechanics and energetics with myocardial adenine nucleotide regulation; and (iii) highlight potential targets for treating myocardial metabolic and mechanical dysfunction associated with these pathways. It is hypothesized that an imbalance in the degradation, salvage, and synthesis of adenine nucleotides leads to a net loss of adenine nucleotides in both acute ischemia and under chronic high-demand conditions associated with the development of heart failure. This reduction in adenine nucleotide levels results in reduced myocardial ATP and increased myocardial inorganic phosphate. Both of these changes have the potential to directly impact tension development and mechanical work at the cellular level. © 2024 American Physiological Society. Compr Physiol 14:5345-5369, 2024.

Effectiveness and safety of different doses of febuxostat compared with allopurinol in the treatment of hyperuricemia: a meta-analysis of randomized controlled trials

BACKGROUND

The prevalence of hyperuricemia has increased steadily with the continuous improvement of living standards. Some studies have reported the clinical effectiveness and safety of different doses of febuxostat in comparison with allopurinol in hyperuricemia treatment, but the sample sizes of the studies have been small, and the results have been inconsistent. We designed this meta-analysis to evaluate the effectiveness and safety of different doses of febuxostat compared with allopurinol in the treatment of hyperuricemia.

METHODS

The Cochrane Library, Embase, PubMed, Web of Science and ClinicalTrials.gov databases were searched to identify randomized controlled trials (RCTs) comparing the use of febuxostat and allopurinol for the treatment of hyperuricemia. The effectiveness and safety of different doses of febuxostat and allopurinol in treating hyperuricemia were assessed using meta-analysis.

RESULTS

A total of 11 randomized controlled trials were included in the meta-analysis. The results of the meta-analysis showed that the percentage of patients achieving serum uric acid levels of 6.0 mg/dL or less was higher among patients taking febuxostat (80 mg/d) than among patients taking allopurinol (200-300 mg/d) [RR = 1.79, 95% CI (1.55, 2.08), P < 0.00001]. However, there was no statistically significant difference in the percentage of patients achieving serum uric acid levels of 6.0 mg/dL or less between febuxostat (40 mg/d) and allopurinol (200-300 mg/d) [RR = 1.10, 95% CI (0.93, 1.31), P = 0.25]. There was also no statistically significant difference in the incidence of gout between the febuxostat (40 mg/d) and allopurinol (200-300 mg/d) [RR = 0.97, 95% CI (0.64, 1.49), P = 0.91] or between the febuxostat (80 mg/d) and allopurinol (200-300 mg/d) [RR = 1.13, 95% CI (0.81, 1.58), P = 0.48].No significant difference in the incidence of major adverse reactions as observed between the febuxostat (40 mg/d) and allopurinol (200-300 mg/d) [RR = 1.16; 95% CI (0.43, 3.16), P = 0.77] or between the febuxostat (80 mg/d) and allopurinol (200-300 mg/d) [RR = 1.06; 95% CI (0.79, 1.42), P = 0.70]. The incidence of adverse cardiovascular events did not differ significantly between the febuxostat (40 mg/d) and allopurinol (200-300 mg/d) [RR = 1.30; 95% CI (0.57, 2.95), P = 0.53] or between the febuxostat (80 mg/d) and allopurinol (200-300 mg/d) [RR = 1.79; 95% CI (0.74, 4.32), P = 0.20].

CONCLUSIONS

Febuxostat (80 mg/d) was associated with a higher percentage of patients achieving serum uric acid levels of 6.0 mg/dL or less than allopurinol (200-300 mg/d), however, febuxostat (80 mg/d) did not exhibit better efficacy in reducing the incidence of gout. More attention should be devoted to the adverse reactions caused by an increase in febuxostat doses.

Discovery of coumaric acid derivatives hinted by coastal marine source to seek for uric acid lowering agents

In this work, a series of novel compounds Spartinin C1-C24 were screened, synthesised and evaluated for inhibiting xanthine oxidase thus lowering serum uric acid level. The backbones were derived from the components of coastal marine source Spartina alterniflora and marketed drugs. The top hits Spartinin C10 & C22 suggested high inhibition percentages (78.54 and 93.74) at 10 μM dosage, which were higher than the positive control Allopurinol. They were low cytotoxic onto human normal hepatocyte cells. Treatment with Spartinin C10 could lower the serum uric acid level to 440.0 μM in the hyperuricemic model mice (723.0 μM), comparable with Allopurinol (325.8 μM). Spartinin C10 was more appreciated than Allopurinol on other serum indexes. The preliminary pharmacokinetics evaluation indicated that the rapid absorption, metabolism and elimination of Spartinin C10 should be further improved. The discovery of pharmaceutical molecules from coastal marine source here might inspire the inter-disciplinary investigations on public health.

Design, synthesis, and evaluation of the in vitro activity of novel dual inhibitors of XOR and URAT1 containing a benzoic acid group

Xanthine oxidoreductase (XOR) and uric acid transporter 1 (URAT1) are involved in the production and reabsorption of uric acid, respectively. However, the currently available individual XOR- or URAT1-targeted drugs have limited efficacy. Thus, strategies for combining XOR inhibitors with uricosuric drugs have been developed. Previous virtual screening identified Compounds 1-5 as hits for the potential dual inhibition of XOR/URAT1. Nevertheless, in vitro experiments yielded unsatisfactory results. The first round of optimization work on those hits was performed, and two series of compounds were designed and synthesized. Compounds of the A series exerted moderate inhibitory effects on URAT1, but extremely weak inhibitory effects on XOR. Compounds of the B series exerted strong inhibitory effects on both XOR and URAT1. B5 exhibited the greatest inhibitory activity, with similar inhibitory effects on XOR and URAT1. The half maximal inhibitory concentration (IC50 ) of XOR was 0.012 ± 0.001 μM, equivalent to that of febuxostat (IC50  = 0.010 ± 0.001 μM). The IC50 of URAT1 was 30.24 ± 3.46 μM, equivalent to that of benzbromarone (IC50  = 24.89 ± 7.53 μM). Through this optimization, the in vitro activity of most compounds of the A and B series against XOR and URAT1 was significantly improved versus that of the hits. Compound B5 should be further investigated.

Serum uric acid: a futile bystander in endothelial function?

PURPOSE

This study aims to investigate the relationship between serum uric acid levels and endothelial function, oxidative stress, and hemodynamic parameters, and to determine if uric acid levels provide additional insights beyond traditional factors like ageing and hypertension in volunteers with low cardiovascular risk factors. Serum uric acid is known for its antioxidant properties, but it may also contribute to cardiovascular risk.

MATERIALS AND METHODS

The study enrolled 40 male participants, divided into three groups based on age and blood pressure status. Group 1 comprised younger participants, group 2 included older individuals without hypertension, and group 3 consisted of older patients with hypertension. The study assessed endothelial function using laser Doppler imaging and measured acetylcholine- and sodium nitroprusside-induced hyperaemia. The heat microcirculatory response was also examined in the presence of L-NAME, an inhibitor of NOS synthase. The study evaluated oxidative stress and arterial stiffness by measuring allantoin, angiotensin II, Homocitrulline/Lysine, and Chloro-Tyrosine/Tyrosine ratios, as well as by performing non-invasive measurements of aortic augmentation indexes and carotid-femoral pulse wave velocity.

RESULTS

The study found that uric acid levels did not differ significantly among the three groups. Augmentation indexes increased with ageing, but hypertension did not have an additional effect. Blood pressure and carotid-femoral pulse wave velocity differed among the groups, with the lowest values among younger participants and the highest values among older individuals with hypertension. Allantoin and angiotensin II levels did not differ among the groups. However, Homocitrulline/Lysine and Chloro-Tyrosine/Tyrosine ratios were significantly lower in young subjects. Correlation and multivariable analysis showed that uric acid had no effect on any of the studied parameters. Despite a strong association between ageing and systolic blood pressure with impaired endothelial function, oxidative stress, and arterial stiffness, only ageing retained a significant effect in the multivariable analysis.

CONCLUSION

In healthy or hypertensive adults with normal renal function, serum uric acid appears to be a futile bystander in endothelial function, oxidative stress, and arterial stiffness, in contrast to ageing, which reduces NO bioavailability. This study suggests that traditional factors such as ageing and hypertension should be the focus of clinical assessment and management of cardiovascular risk, rather than uric acid levels.

Target Screen of Anti-Hyperuricemia Compounds from Cortex Fraxini In Vivo Based on ABCG2 and Bioaffinity Ultrafiltration Mass Spectrometry

The ATP-binding cassette (ABC) transporter ABCG2 is a significant urate transporter with a high capacity, and it plays a crucial role in the development of hyperuricemia and gout. Therefore, it has the potential to be targeted for therapeutic interventions. Cortex Fraxini, a traditional Chinese medicine (TCM), has been found to possess anti-hyperuricemia properties. However, the specific constituents of Cortex Fraxini responsible for this effect are still unknown, particularly the compound that is responsible for reducing uric acid levels in vivo. In this study, we propose a target screening protocol utilizing bio-affinity ultrafiltration mass spectrometry (BA-UF-MS) to expediently ascertain ABCG2 ligands from the plasma of rats administered with Cortex Fraxini. Our screening protocol successfully identified fraxin as a potential ligand that interacts with ABCG2 when it functions as the target protein. Subsequent investigations substantiated fraxin as an activated ligand of ABCG2. These findings imply that fraxin exhibits promise as a drug candidate for the treatment of hyperuricemia. Furthermore, the utilization of BA-UF-MS demonstrates its efficacy as a valuable methodology for identifying hit compounds that exhibit binding affinity towards ABCG2 within TCMs.

Association between Asymptomatic Hyperuricemia with Adiposity Indices: A Cross-Sectional Study in a Spanish Population

INTRODUCTION

New anthropometric indices have been developed as an alternative to body mass index (BMI) and waist circumference (WC) to assess body mass and visceral fat. Asymptomatic hyperuricemia is considered an independent cardiovascular risk factor. Currently, little is known about the relationship between asymptomatic hyperuricemia and several new anthropometric indices. This study aimed to assess the association between the presence of asymptomatic hyperuricemia and anthropometric indices, both novel and traditional.

METHODS

This study analyzed 1094 Spanish subjects who consecutively visited the cardiovascular risk consultation of the University Hospital San Pedro de Alcántara of Cáceres, Spain, between June 2021 and September 2022. Anthropometric measures, including traditional and novel indices, were determined. The asymptomatic hyperuricemia group was defined according to serum uric acid levels.

RESULTS

All the anthropometric indices studied, including new and traditional, were significantly greater among patients with asymptomatic hyperuricemia, except for WWI. In multiple linear regression analysis, serum uric acid levels were significantly correlated with BMI, WHR, WHtR, AVI, BAI, BRI, CUN-BAE, and WWI but not ABSI or CI. In the univariate analysis, all indices were associated with asymptomatic hyperuricemia (p < 0.05); however, only WHtR (adjusted OR: 2.93; 95% CI: 1.03-8.37; p = 0.044), AVI (adjusted OR: 1.46; 95% CI: 1.04-2.04; p = 0.026), and BRI (adjusted OR: 1.66; 95% CI: 1.19-2.32; p = 0.003) were significantly associated in multivariate analysis. Finally, WHtR, AVI, and BRI provided the largest AUCs.

CONCLUSIONS

Our findings showed that WHtR, AVI, and BRI were independently positively associated with asymptomatic hyperuricemia and could be good predictors.

Past, present and future of xanthine oxidase inhibitors: design strategies, structural and pharmacological insights, patents and clinical trials

Xanthine oxidase, a molybdo-flavoenzyme, and an isoform of xanthine dehydrogenase both exist as xanthine oxidoreductase and are responsible for purine catabolism. Xanthine oxidase is more involved in pathological conditions when extensively modulated. Elevation of xanthine oxidase is not only the prime cause of gout but is also responsible for various hyperuricemia associated pathological conditions like diabetes, chronic wounds, cardiovascular disorders, Alzheimer's disease, etc. Currently available xanthine oxidase inhibitors in clinical practice (allopurinol, febuxostat and topiroxostat) suffer from fatal side effects that pose a serious problem to the healthcare system, raising global emergency to develop novel, potent and safer xanthine oxidase inhibitors. This review will provide key and systematic information about: a. design strategies (inspired from both marketed drugs in clinical practice and natural products), structural insights and pharmacological output (xanthine oxidase inhibition and associated activities) of various pre-clinical candidates reported by various research groups across the globe in the past two decades; b. patented xanthine oxidase inhibitors published in the last three decades and c. clinical trials and their outcomes on approved drug candidates. Information generated in this review has suggested fragment-based drug design (FBDD) and molecular hybridization techniques to be most suitable for development of desired xanthine oxidase inhibitors as one provides high selectivity toward the enzyme and the other imparts multifunctional properties to the structure and both may possess capabilities to surpass the limitations of currently available clinical drugs. All in combination will exclusively update researchers working on xanthine oxidase inhibitors and allied areas and potentially help in designing rational, novel, potent and safer xanthine oxidase inhibitors that can effectively tackle xanthine oxidase related disease conditions and disorders.

Celebrating Versatility: Febuxostat's Multifaceted Therapeutic Application

Febuxostat, initially developed as a xanthine oxidase inhibitor to address hyperuricemia in gout patients, has evolved into a versatile therapeutic agent with multifaceted applications. This review provides a comprehensive overview of febuxostat's mechanism of action, its effectiveness in gout management, its cardiovascular safety profile, renal and hepatic effects, musculoskeletal applications, safety considerations, and emerging research prospects. Febuxostat's primary mechanism involves selective inhibition of xanthine oxidase, resulting in reduced uric acid production. Its pharmacokinetics require personalized dosing strategies based on individual characteristics. In gout management, febuxostat offers a compelling alternative, effectively lowering uric acid levels, relieving symptoms, and supporting long-term control, especially for patients intolerant to allopurinol. Recent studies have demonstrated its cardiovascular safety, and it exhibits minimal hepatotoxicity, making it suitable for those with liver comorbidities. Febuxostat's potential nephroprotective effects and kidney stone prevention properties are noteworthy, particularly for gout patients with renal concerns. Beyond gout, its anti-inflammatory properties hint at applications in musculoskeletal conditions and a broader spectrum of clinical contexts, including metabolic syndrome. Emerging research explores febuxostat's roles in cardiovascular health, neurological disorders, rheumatoid arthritis, and cancer therapy, driven by its anti-inflammatory and antioxidative properties. Future directions include personalized medicine, combination therapies, mechanistic insights, and ongoing long-term safety monitoring, collectively illuminating the promising landscape of febuxostat's multifaceted therapeutic potential.

Expert consensus guidelines for the prophylaxis and management of tumor lysis syndrome in the United States: Results of a modified Delphi panel

INTRODUCTION

Tumor lysis syndrome (TLS), which occurs spontaneously or in response to anticancer treatment, results in the release of intracellular potassium, phosphorus, and nucleic acids into the bloodstream, which results in secondary clinical complications that may be fatal. Prior TLS guidelines do not take into consideration potent novel oncologic agents or contemporary treatment paradigms with increased risk of TLS. Thus, a modified Delphi panel of experts was convened to provide an update for TLS management guidelines based upon a combination of supporting literature and practice consensus.

METHODS

A three-round modified Delphi process was implemented. For round 1, nine expert panelists completed a web-based questionnaire developed using published literature. In round 2, panelists were asked to reconsider their answers to questions that did not reach consensus (defined as ≥ 66% agreement among voting panelists). Round 3 was an unblinded, moderated virtual meeting to discuss any remaining questions that did not reach consensus.

RESULTS

Detailed recommendations are given for prophylaxis, monitoring, and management of TLS risks and complications, with hydration being a key element of TLS prophylaxis and management. Guidelines for the management of acute effects of TLS and prevention of long-term renal effects include management of hyperkalemia, hypocalcemia, hyperphosphatemia, and hyperuricemia.

DISCUSSION

Although the control of uric acid levels is quite effective with currently available agents, panelists emphasize the importance of monitoring and treating other dangerous electrolyte abnormalities such as hyperkalemia and hyperphosphatemia. Guidelines from this modified Delphi panel should aid clinicians in preventing and managing TLS.

Emerging Urate-Lowering Drugs and Pharmacologic Treatment Strategies for Gout: A Narrative Review

Hyperuricemia with consequent monosodium urate crystal deposition leads to gout, characterized by painful, incapacitating inflammatory arthritis flares that are also associated with increased cardiovascular event and related mortality risk. This narrative review focuses on emerging pharmacologic urate-lowering treatment (ULT) and management strategies in gout. Undertreated, gout can progress to palpable tophi and joint damage. In oral ULT clinical trials, target serum urate of < 6.0 mg/dL can be achieved in ~ 80-90% of subjects, with flare burden reduction by 1-2 years. However, real-world ULT results are far less successful, due to both singular patient nonadherence and prescriber undertreatment, particularly in primary care, where most patients are managed. Multiple dose titrations commonly needed to optimize first-line allopurinol ULT monotherapy, and substantial potential toxicities and other limitations of approved, marketed oral monotherapy ULT drugs, promote hyperuricemia undertreatment. Common gout comorbidities with associated increased mortality (e.g., moderate-severe chronic kidney disease [CKD], type 2 diabetes, hypertension, atherosclerosis, heart failure) heighten ULT treatment complexity and emphasize unmet needs for better and more rapid clinically significant outcomes, including attenuated gout flare burden. The gout drug armamentarium will be expanded by integrating sodium-glucose cotransporter-2 (SGLT2) inhibitors with uricosuric and anti-inflammatory properties as well as clinically indicated antidiabetic, nephroprotective, and/or cardioprotective effects. The broad ULT developmental pipeline is loaded with multiple uricosurics that selectively target uric acid transporter 1 (URAT1). Evolving ULT approaches include administering selected gut anaerobic purine degrading bacteria (PDB), modulating intestinal urate transport, and employing liver-targeted xanthine oxidoreductase mRNA knockdown. Last, emerging measures to decrease the immunogenicity of systemically administered recombinant uricases should simplify treatment regimens and further improve outcomes in managing the most severe gout phenotypes.

Serum uric acid to creatinine ratio as a risk factor for mortality among patients on continuous ambulatory peritoneal dialysis: a multi-center retrospective study

BACKGROUND

Serum uric acid to serum creatinine ratio (SUA/Scr) has emerged as a new biomarker, which is significantly associated with several metabolic diseases. However, no study has investigated the association between SUA/Scr and mortality among patients on continuous ambulatory peritoneal dialysis (CAPD).

METHODS

In this multicenter retrospective cohort study, we enrolled CAPD patients in eight tertiary hospitals in China from 1 January 2005 to 31 May 2021. Cox proportional hazard models were used to determine the relationship between SUA/Scr and mortality.

RESULTS

A total of 2480 patients were included; the mean age was 48.9 ± 13.9 years and 56.2% were males. During 12648.0 person-years of follow-up, 527 (21.3%) patients died, of which 267 (50.7%) deaths were caused by cardiovascular disease. After multivariable adjustment for covariates, per unit increase in SUA/Scr was associated with a 62.9% (HR, 1.629 (95% confidence interval (CI) 1.420-1.867)) and 73.0% (HR, 1.730 (95% CI 1.467-2.041)) higher risk of all-cause and cardiovascular mortality. Results were similar when categorized individuals by SUA/Scr quartiles. Compared with the lowest quartile of SUA/Scr, the highest and the second highest quartile of SUA/Scr had a 2.361-fold (95% CI 1.810-3.080) and 1.325-fold (95% CI 1.003-1.749) higher risk of all-cause mortality, as well as a 3.701-fold (95% CI 2.496-5.489) and 2.074-fold (95% CI 1.387-3.100) higher risk of cardiovascular mortality. Multivariable-adjusted spline regression models showed nonlinear association of SUA/Scr with mortality in CAPD patients.

CONCLUSIONS

Higher levels of SUA/Scr were associated with higher risk of all-cause and cardiovascular mortality in CAPD patients.