Decreased Serum Uric Acid Levels Research Articles

Baseline gut microbiome as a predictive biomarker of response to probiotic adjuvant treatment in gout management

Gout is characterized by dysregulation of uric acid (UA) metabolism, and the gut microbiota may serve as a regulatory target. This two-month randomized, double-blind, placebo-controlled trial aimed to investigate the additional benefits of coadministering Probio-X alongside febuxostat. A total of 160 patients with gout were randomly assigned to either the probiotic group (n = 120; Probio-X [1 ×1011 CFU/day] with febuxostat) or the placebo group (n = 40; placebo material with febuxostat). Coadministration of Probio-X significantly decreased serum UA levels and the rate of acute gout attacks (P < 0.05). Based on achieving a target sUA level (360 μmol/L) after the intervention, the probiotic group was further subdivided into probiotic-responsive (ProA; n = 54) and probiotic-unresponsive (ProB; n = 66) subgroups. Post-intervention clinical indicators, metagenomic, and metabolomic changes in the ProB and placebo groups were similar, but differed from those in the ProA group, which exhibited significantly lower levels of acute gout attack, gout impact score, serum indicators (UA, XOD, hypoxanthine, and IL-1β), and fecal gene abundances of UA-producing pathways (KEGG orthologs of K13479 and K01487; gut metabolic modules for formate conversion and lactose and galactose degradation). Additionally, the ProA group showed significantly higher levels (P < 0.05) of gut SCFAs-producing bacteria and UA-related metabolites (xanthine, hypoxanthine, bile acids) after the intervention. Finally, we established a gout metagenomic classifier to predict probiotic responsiveness based on subjects’ baseline gut microbiota composition. Our results indicate that probiotic-driven therapeutic responses are highly individual, with the probiotic-responsive cohort benefitting significantly from probiotic coadministration.

Pegloticase-Induced Rapid Uric Acid Lowering and Kidney and Cardiac Health Markers in Youth-Onset Type 2 Diabetes: A Pilot Clinical Trial

Rationale & ObjectiveElevated serum uric acid (SUA) is a risk factor for incident hypertension and diabetic kidney disease in young persons with type 2 diabetes (T2D), particularly men. The acute benefit of aggressively lowering SUA on kidney and cardiovascular function in this population remains underexplored. This study was conducted to investigate the impact of a single pegloticase infusion on kidney and cardiovascular function. Study DesignAn open-label pilot trial. Setting & ParticipantsThe study involved 10 young adult males with youth-onset T2D and SUA levels ≥5 mg/dL. Intervention(s)Participants received a single infusion of pegloticase (8 mg). Evaluations were conducted using iohexol-based measured glomerular filtration rate (mGFR) and cardiac/kidney MRI before and one week after infusion. OutcomesThe primary outcomes were changes in SUA and mGFR one week after pegloticase infusion. ResultsNine participants (mean [±SD] age 22±5 years, HbA1c 8.6±3.3%, BMI 40.1±11.0 kg/m2, SUA 6.7±1.1 mg/dL) completed the pegloticase infusion and were included in the analysis. One week after the infusion, median [p25,p75] SUA concentrations dropped from 6.4 [5.6,7.6] to 0.5 [0.5,4.6] mg/dL (p=0.01). Mean mGFR increased from 113±20 to 122±19 ml/min per 1.73 m2 (p=0.004). Among responders (SUA reduction ≥3 mg/dL), an increase in mGFR correlated with an increase in renal artery blood flow (r:0.60, p=0.24) and decrease in SUA (r:-0.79, p=0.05). Mean MRI peak longitudinal cardiac strain additionally decreased from 15.4±2.2 to 13.1±2.2 % (p=0.03) in these responders. LimitationsThe pilot nature of the study and the small sample size limit the generalizability of the findings. ConclusionsIn young adult males with T2D, a single pegloticase infusion decreased SUA levels, which increased mGFR and was strongly associated with increased renal blood flow and impaired cardiac global longitudinal strain. Further research is required to assess the long-term efficacy and safety of pegloticase in patients with T2D.

Effects and mechanisms of Polygonati Rhizoma polysaccharide on potassium oxonate and hypoxanthine-induced hyperuricemia in mice

Hyperuricemia, a prevalent metabolic disturbance intricately linked to gout and chronic kidney disease (CKD), may be relieved by traditional Chinese medicine Polygonati Rhizoma. It is derived from the rhizomes of Polygonatum sibiricum, Polygonatum kingianum, and Polygonatum cyrtonema, which are rich in polysaccharides and are effective hyperuricemia alleviators. This study investigated the potential of Polygonatum sibiricum polysaccharide (PSP) in managing hyperuricemia. PSP (125, 250, and 500 mg/kg, i.g.) or allopurinol was administered to hyperuricemia mice treated with potassium oxonate and hypoxanthine for two weeks. PSP effectively decreased serum uric acid levels by inhibiting xanthine oxidase and adenosine deaminase activity and expression in the liver and modulating uric acid-related transporters (URAT1, OAT1, and OAT3) in the kidney. PSP lowered serum creatinine and blood urea nitrogen levels, alleviating hyperuricemia-induced renal tubular epithelial-mesenchymal fibrosis. In vitro, PSP promoted mitochondrial biogenesis via the PGC-1α/NRF1/TFAM pathway, suppressed reactive oxygen species production, and prevented cytochrome C and dynamin-related protein 1 dysregulation in HK-2 cells. Furthermore, PSPA (Mw 4.0 kDa) and PSPB (Mw 112.2 kDa) isolated from PSP exhibit different uric acid-lowering mechanisms. In conclusion, our findings highlight the therapeutic potential of PSP and its nephroprotective effects in hyperuricemia, thereby supporting its development as a therapeutic agent for hyperuricemia.

Lipidomics and metabolomics investigation into the effect of DAG dietary intervention on hyperuricemia in athletes

The occurrence of hyperuricemia (HUA; elevated serum uric acid) in athletes is relatively high despite that exercise can potentially reduce the risk of developing this condition. Although recent studies have shown the beneficial properties of DAG in improving overall metabolic profiles, a comprehensive understanding of the effect of DAG in modulating HUA in athletes is still lacking. In this study, we leveraged combinatorial lipidomics and metabolomics to investigate the effect of replacing TAG with DAG in the diet of athletes with HUA. A total of 1,074 lipids and metabolites from 94 classes were quantitated in serum from 33 athletes, who were categorized into responders and non-responders based on whether serum uric acid levels returned to healthy levels after the DAG diet intervention. Lipidomics and metabolomics analyses revealed lower levels of xanthine and uric acid in responders, accompanied by elevated plasmalogen phosphatidylcholines and diminished acylcarnitine levels. Our results highlighted the mechanisms behind how the DAG diet circumvented the risk and effects associated with high uric acid via lowered triglycerides at baseline influencing the absorption of DAG resulting in a decline in ROS and uric acid production, increased phospholipid levels associated with reduced p-Cresol metabolism potentially impacting on intestinal excretion of uric acid as well as improved ammonia recycling contributing to decreased serum uric acid levels in responders. These observed alterations might be suggestive that successful implementation of the DAG diet can potentially minimize the likelihood of a potentially vicious cycle occurring in high uric acid, elevated ROS, and impaired mitochondrial metabolism environment.

Associations of serum uric acid variability with neuroimaging metrics and cognitive decline: a population-based cohort study

BackgroundThe relationship between variation in serum uric acid (SUA) levels and brain health is largely unknown. This study aimed to examine the associations of long-term variability in SUA levels with neuroimaging metrics and cognitive function.MethodsThis study recruited 1111 participants aged 25–83 years from a multicenter, community-based cohort study. The SUA concentrations were measured every two years from 2006 to 2018. We measured the intraindividual SUA variability, including the direction and magnitude of change by calculating the slope value. The associations of SUA variability with neuroimaging markers (brain macrostructural volume, microstructural integrity, white matter hyperintensity, and the presence of cerebral small vessel disease) and cognitive function were examined using generalized linear models. Mediation analyses were performed to assess whether neuroimaging markers mediate the relationship between SUA variation and cognitive function.ResultsCompared with the stable group, subjects with increased or decreased SUA levels were all featured by smaller brain white matter volume (beta = − 0.25, 95% confidence interval [CI] − 0.39 to − 0.11 and beta = − 0.15, 95% CI − 0.29 to − 0.02). Participants with progressively increased SUA exhibited widespread disrupted microstructural integrity, featured by lower global fractional anisotropy (beta = − 0.24, 95% CI − 0.38 to − 0.10), higher mean diffusivity (beta = 0.16, 95% CI 0.04 to 0.28) and radial diffusivity (beta = 0.19, 95% CI 0.06 to 0.31). Elevated SUA was also associated with cognitive decline (beta = − 0.18, 95% CI − 0.32 to − 0.04). White matter atrophy and impaired brain microstructural integrity mediated the impact of SUA increase on cognitive decline.ConclusionsIt is the magnitude of SUA variation rather than the direction that plays a critical negative role in brain health, especially for participants with hyperuricemia. Smaller brain white matter volume and impaired microstructural integrity mediate the relationship between increased SUA level and cognitive function decline. Long-term stability of SUA level is recommended for maintaining brain health and preventing cognitive decline.

#2595 Evolution of hemoglobin and serum uric acid levels after SGLT2i initiation in patients with and without diabetic nephropathy

Abstract Background and Aims Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are glucose-lowering drugs that inhibit glucose reabsorption in the proximal tubule, enhancing urinary glucose excretion. SGLT2i exhibit significant cardio- and renoprotective effects due to their capacity to increase diuresis and weight loss and reduce intraglomerular and blood pressure. Moreover, recent studies have described the potential of SGLT2i to improve additional cardiovascular risk factors, such as anemia or hyperuricemia. In this study, we aimed to describe the evolution of hemoglobin (Hb) and serum uric acid (SUA) levels in CKD patients with and without diabetic nephropathy before and after the initiation of SGLT2i therapy. Method CKD patients with and without diabetic nephropathy that were followed in the outpatient clinic of a tertiary referral academic hospital during January 2020 to September 2023 and that started SGLT2i therapy during that period were randomly recruited in the study. Patient characteristics, CKD staging, and levels of Hb and SUA before and after SGLT2i initiation were compared between groups. Hb and SUA levels were averaged considering all available laboratory controls during the last 12 months before treatment initiation and any available controls after treatment start. Results Demographic and clinical characteristics of enrolled patients are summarized in Fig. 1. Subjects with diabetic nephropathy were significantly older, more commonly hypertensive, presented worse kidney function, had received SGLT2i for a lengthier time and had lower hemoglobin values. We observed no change in hemoglobin levels after the initiation of SGLT2i in our sample, independently of diabetic nephropathy status or CKD stage (Fig. 2A, C). In contrast, SUA levels decreased significantly both in patients with and without diabetic nephropathy (Fig. 2B). This effect was observed across all the spectrum of CKD in our sample (Fig. 2D). Conclusion In our sample, SGLT2i initiation was associated with a significant decrease in SUA levels, both in patients with and without diabetic nephropathy and independently of CKD stage, which may help to explain its cardio- and nephroprotective effects. No change in Hb levels was observed, possibly due to a low prevalence of anaemia in our sample.

Nonlinear relationship between oxidative balance score and hyperuricemia: analyses of NHANES 2007–2018

BackgroundLimited data regarding the correlation between oxidative balance score (OBS) and hyperuricemia highlights the necessity for thorough investigations. This study aims to examine the link between OBS, which incorporates dietary and lifestyle factors, and the occurrence of hyperuricemia.MethodsWe conducted a cross-sectional study involving 13,636 participants from the 2007–2018 National Health and Nutrition Examination Survey (NHANES). The oxidative balance score (OBS) was determined based on four lifestyle factors and sixteen dietary nutrients. We assessed the levels of serum uric acid (SUA) and the occurrence of hyperuricemia as outcomes. Weighted logistic regression and linear models were used for statistical analysis, using Restricted Cubic Splines (RCS) to examine potential nonlinear associations. Subgroup analysis and sensitivity assessments were performed to identify any variations and ensure the robustness of the findings.ResultsHigher OBS was consistently correlated with decreased SUA levels and a reduced prevalence of hyperuricemia. RCS highlighted a significant negative nonlinear association, particularly in females. Subgroup analysis revealed gender-based differences and interactive correlation, providing additional insights regarding OBS and hyperuricemia relationship.ConclusionThis study underscores a robust negative correlation between OBS and SUA levels as well as the incidence of hyperuricemia, emphasizing the importance of dietary and lifestyle factors. Incorporating RCS, subgroup analysis, and sensitivity assessments enhances the depth of our findings, providing valuable insights for further research.

Bariatric Surgery and Its Metabolic Echo Effect on Serum Uric Acid Levels.

Bariatric surgery (BS) has been a significant means of reducing weight in obese individuals. The metabolic changes after bariatric surgery are crucial as they extend its advantages beyond weight loss. As its name implies, "metabolic surgery" also addresses obesity-related metabolic concerns. Bariatric surgery has always been associated with lessened serum uric acid (SUA) levels. In this review, we examined current studies to understand how surgical therapies impact serum uric acid levels. Strongly minded on the extent and timing of changes in the level of serum uric acid after bariatric surgeries. We conducted a comprehensive search for relevant current studies in PubMed, Google Scholar, JAMA, and the Cochrane Library until February 1, 2024. We aimed to analyze the metabolic advantages of bariatric surgery, focusing on its function in treating hyperuricemia and lowering the risk of associated disorders. Our review elaborates on factors contributing to decreased serum uric acid levels after bariatric surgery, such as alterations in renal function, insulin sensitivity, and inflammatory markers.

Baseline and change in serum uric acid level over time and resolution of nonalcoholic fatty liver disease in young adults: The Kangbuk Samsung Health Study.

To determine the association between: (i) baseline serum uric acid (SUA) level and (ii) SUA changes over time, and nonalcoholic fatty liver disease (NAFLD) resolution. A retrospective cohort study, comprising 38 483 subjects aged <40 years with pre-existing NAFLD, was undertaken. The effects of SUA changes over time were studied in 25 266 subjects. Participants underwent a health examination between 2011 and 2019, and at least one follow-up liver ultrasonography scan up to December 2020. Exposures included baseline SUA level and SUA changes between baseline and subsequent visits, categorized into quintiles. The reference group was the third quintile (Q3) containing zero change. The primary endpoint was resolution of NAFLD. During a median follow-up of 4 years, low baseline SUA level and decreases in SUA levels over time were independently associated with NAFLD resolution (p for trend <0.001). Using SUA as a continuous variable, the likelihood of NAFLD resolution was increased by 10% and 13% in men and women, respectively, per 1-mg/dL decrease in SUA. In a time-dependent model with changes in SUA treated as a time-varying covariate, adjusted hazard ratios (95% confidence intervals) for NAFLD resolution comparing Q1 (highest decrease) and Q2 (slight decrease) to Q3 (reference) were 1.63 (1.49-1.78) and 1.23 (1.11-1.35) in men and 1.78 (1.49-2.12) and 1.18 (0.95-1.46) in women, respectively. Low baseline SUA levels and a decrease in SUA levels over time were both associated with NAFLD resolution in young adults.

The effects of short term citrulline malate supplementation on oxidative stress and muscle damage in trained soccer players

There is some evidence that citrulline malate (CM) limits the deleterious effect of oxidative stress in athletes, but its effect on team sports like soccer is not clear. Thus, the current research is designed to investigate the effect of short-term CM supplementation on oxidative stress and muscle damage markers in trained soccer players. In this randomized double-blind controlled trial, 28 healthy, highly-trained male soccer players were selected and randomly assigned into 2 groups to take 6 g/day CM or placebo for 7 days. Blood samples were then taken in a resting-state at baseline and 24 h after the 7-day supplement intervention; and serum malondialdehyde (MDA), total antioxidant capacity (TAC), catalase (CAT), glutathione (GSH), superoxide dismutase (SOD), lactate dehydrogenase (LDH), creatine kinase (CK), and uric acid levels were measured. Compared to the baseline, CM significantly decreased serum uric acid levels (P = 0.03) and significantly increased serum LDH concentrations (P = 0.002). However, there were no significant changes in serum levels of MDA, CAT, GSH, TAC, SOD, LDH CK, and uric acid compared to the placebo group (P > 0.05). It appears that short-term CM supplementation does not improve oxidative stress and muscle damage in soccer players. Further investigations should be conducted to fully understand the effects of CM on soccer players.

Decoding connections in the European population: serum uric acid, sex hormone-binding globulin, total testosterone, estradiol, and female infertility - advanced bidirectional and mediative Mendelian randomization.

Despite observational links between serum uric acid (SUA), sex hormone-related phenotypes, and female infertility, the causality behind these associations remains uncertain. This study utilizes Bidirectional Two-Sample and Mediation Mendelian Randomization to explore the causal relationships and mediation effects of sex hormone-binding globulin (SHBG), total testosterone (TT), and estradiol on these associations. We analyzed single-nucleotide polymorphisms (SNPs) associated with SUA and sex hormone levels using data from large-scale GWAS of European populations. Female infertility data were sourced from 6,481 cases and 75,450 controls in the FinnGen Consortium. We employed methods including Inverse Variance Weighted (IVW), Weighted Median, and MR-Egger regression to assess causality. We found that elevated SUA levels causally increase the risk of female infertility (IVW OR: 1.13, P=0.047). Elevated SUA levels significantly decrease SHBG levels (β=-0.261; P=2.177e-04), with SHBG mediating 27.93% of the effect of SUA on infertility (OR=0.854; 95%CI, 0.793-0.920; P=2.853e-05). Additionally, elevated TT levels, which were associated with decreased SUA levels (β=-0.127), showed an indirect effect on infertility mediated by SUA (β=-0.0187; 95% CI, -0.041 to -0.003; P=0.046). Our findings demonstrate causal links between high SUA and increased risk of female infertility mediated by hormonal factors such as SHBG and TT. These insights suggest new avenues for infertility treatment and highlight the need for further research into these mechanisms.

Correlation between serum uric acid and body fat distribution in patients with MAFLD

BackgroundMetabolic dysfunction associated with fatty liver disease (MAFLD) is often correlated with obesity and hyperuricemia. The present study aimed to determine the association between serum uric acid (SUA) and central fat distribution in patients with MAFLD.MethodsA total of 485 patients were classified into the following groups: (1) controls without MAFLD and hyperuricemia (HUA), (2) MAFLD with normal SUA, and (3) MAFLD with HUA. DUALSCAN HDS-2000 was used to measure visceral fat (VAT) and subcutaneous fat (SAT). Dual-energy X-ray absorptiometry (DEXA) was used to measure body fat distribution.ResultsMAFLD patients with HUA had remarkably higher BMI, fasting insulin, OGIRT AUC, ALT, AST, TG, VAT, SAT, Adipo-IR, trunk fat mass, android fat, and total body fat than MAFLD patients with normal SUA (all p < 0.05). The increase in VAT, SAT, CAP, Adipo-IR, upper limbs fat mass, trunk fat mass, and android fat, as well as the percentage of MAFLD, were significantly correlated with the increase in SUA. The percentage of MAFLD patients with HUA increased significantly with increasing VAT or SAT, as determined by the Cochran–Armitage trend test (all p < 0.05). Furthermore, VAT (OR = 1.01 CI: 1.00, 1.03; p < 0.05) and adipo-IR (OR = 1.09 CI: 1.00, 1.19; p < 0.05) were associated with circling SUA in MAFLD after adjusting for sex, age, TG, TC, HOMA-IR, and BMI.ConclusionAbdominal fat promotes the co-existence of HUA and MAFLD, while weight loss, especially, decreasing VAT, is of great importance to decrease SUA levels and manage MAFLD.

Effects of febuxostat on markers of endothelial dysfunction and renal progression in patients with chronic kidney disease

Hyperuricemia relates to chronic kidney disease (CKD) progression and impaired endothelial function. Febuxostat is potent and effective for decreasing serum uric acid levels. Information for the effect of febuxostat treatment on markers of endothelial dysfunction and renal injury among patients with CKD remains limited. A total of 84 patients with CKD stages III-IV with asymptomatic hyperuricemia were randomly assigned to either the febuxostat (40 mg/day, N = 42) or the matching control (N = 42) group for 8 weeks. Serum asymmetric dimethylarginine (ADMA), estimated glomerular filtration rate (eGFR), urine albumin, high sensitivity C-reactive protein (hs-CRP), ankle brachial index (ABI) and serum uric acid were measured at baseline and at the end of study. Febuxostat administration significantly reduced the serum uric acid concentration among patients with CKD when compared with control [− 3.40 (95% CI − 4.19 to − 2.62) vs. − 0.35 (95% CI − 0.76 to 0.06) mg/dL; P < 0.001, respectively). No significant difference in the changes in serum ADMA, hs-CRP, eGFR and albuminuria was identified between the two groups. Subgroup analysis among patients with decreased serum uric acid after febuxostat, the estimated GFR change between the febuxostat and the control group showed significant difference at 8 weeks (2.01 (95% CI 0.31 to 3.7) vs. 0.04 (95% CI − 1.52 to 1.61) mL/min/1.73 m2; P = 0.030, respectively). Adverse events specific to febuxostat were not observed. Febuxostat effectively reduced serum uric acid in the CKD population without improving endothelial dysfunction. It was able to preserve renal function in the subgroup of patients with CKD and lower serum uric acid level after treatment.Trial registration: Thai Clinical Trials, TCTR20210224005: 24/022021 http://www.thaiclinicaltrials.org/show/TCTR20210224005.

Study on the mechanism of Orthosiphon aristatus (Blume) Miq. in the treatment of hyperuricemia by microbiome combined with metabonomics

Ethnopharmacological relevanceGrowing evidence indicates that hyperuricemia is closely associated with gut microbiota dysbiosis. Orthosiphon aristatus (Blume) Miq. (O. aristatus), as a traditional Chinese medicine, has been widely used to treat hyperuricemia in China. However, the mechanism by which O. aristatus treats hyperuricemia has not been clarified. Aim of the studyIn this study, we investigated whether the molecular mechanism underlying the anti-hyperuricemia effect of O. aristatus is related to the regulation of gut microbiota by 16S rDNA gene sequencing combined with widely targeted metabolomics. Materials and methodsHyperuricemia was induced in rats by administration of 10% fructose and 20% yeast, and the uricosuric effect was assessed by measuring the uric acid (UA) levels in serum and cecal contents. Intestinal morphology was observed by hematoxylin and eosin (HE) staining. To explore the effects of O. aristatus on the gut microbiota and its metabolites, we utilized 16S rDNA gene sequencing combined with widely targeted metabolomics. Furthermore, metabolic pathway enrichment analysis was performed on the screened differential metabolites. The real time quantitative polymerase chain reaction (RT-PCR) and western blotting (WB) were used to detect the expression of relevant proteins in the key pathway. ResultsOur results indicated that O. aristatus intervention decreased serum UA levels and increased the UA levels in cecal contents in hyperuricemic rats. Additionally, O. aristatus improved intestinal morphology and altered the composition of the gut microbiota and its metabolites. Specifically, 16S rDNA revealed that O. aristatus treatment significantly reduced the abundance of unidentified-Ruminococcaceae and Lachnospiraceae-NK4A136-group. Meanwhile, widely targeted metabolomics showed that 17 metabolites, including lactose, 4-oxopentanoate and butyrate, were elevated, while 55 metabolites, such as flavin adenine dinucleotide and xanthine, were reduced. Metabolic pathway enrichment analysis found that O. aristatus was mainly involved in purine metabolism. Moreover, RT-PCR and WB suggested that O. aristatus could significantly up-regulate the expression of UA excretion transporter ATP-binding cassette subfamily G member 2 (ABCG2) in the intestine. ConclusionO. aristatus exerts UA-lowering effect by regulating the gut microbiota and ABCG2 expression, indicating that this herb holds great promise in the treatment of hyperuricemia.

Serum Uric Acid Levels Are Related to Diabetic Peripheral Neuropathy, Especially for Motor Conduction Velocity of Tibial Nerve in Type 2 Diabetes Mellitus Patients.

Oxidative stress is one of the most critical factors that contribute to the pathogenesis of neuronal damage, including diabetic peripheral neuropathy (DPN). Uric acid is a kind of natural antioxidant that plays a major role in the antioxidant capacity against oxidative stress. Here, we aim to determine the role of serum uric acid (SUA) in the DPN of patients with type 2 diabetes mellitus (T2DM). Patients and Methods. 106 patients with T2DM were recruited and divided into the DPN group and the control group. Clinical parameters, especially for motor nerve fiber conduction velocity and sensory nerve fiber conduction velocity, were collected. Differences between T2DM patients with and without DPN were compared. Correlation and regression analyses were performed to explore the association between SUA and DPN. Compare with 57 patients with DPN, 49 patients without DPN showed lower HbA1c and elevated SUA levels. Additionally, SUA levels are negatively associated with the motor conduction velocity of tibial nerve with or without adjusting for HbA1c. Besides, it is suggested that decreased SUA levels may influence the motor conduction speed of the tibial nerve by multiple linear regression analysis. Moreover, we demonstrated that decreased SUA level is a risk factor for DPN in patients with T2DM by binary logistic regression analysis. Lower SUA is a risk factor for DPN in patients with T2DM. Additionally, decreased SUA may influence the damage of peripheral neuropathy, especially for motor conduction velocity of the tibial nerve.

Pyroglutamylproline purified from fermented barley extract increases ABCG2 expression in Caco-2 cells

Fermented barley extract P (FBEP) prepared from barley shochu distillation by-product has been reported to lower serum uric acid (UA) by increasing urinary excretion of UA. ATP-binding cassette subfamily G member 2 (ABCG2) is a transporter responsible for UA efflux from the intestinal tract and kidneys. This study aimed to identify, among the compounds isolated from FBEP using high-performance liquid chromatography, the components that promote ABCG2 expression in Caco-2 cells. Pyroglutamylproline (pEP) increased the expression of ABCG2 in Caco-2 cells at the gene and protein levels. These results suggest that the pEP contained in FBEP may decrease serum UA levels by increasing the expression of urate efflux transporters in the intestinal epithelium and promoting UA excretion.

Dietary patterns, uric acid levels, and hyperuricemia: a systematic review and meta-analysis.

Background: Studies investigating the effects of dietary intake on serum uric acid (SUA) and hyperuricemia have yielded inconsistent results. Therefore, we conducted a meta-analysis to assess the associations between various dietary patterns and SUA levels as well as hyperuricemia. Methods: We searched PubMed, Web of Science, and EMBASE databases for relevant articles examining the association between dietary intake and SUA levels and/or hyperuricemia published until March 2023. Dietary intake patterns were classified into plant-based, animal-based, and mixed dietary patterns based on predominant foods. The pooled effect sizes of eligible studies and their corresponding 95% confidence intervals (CIs) were estimated using random-effects models. Publication bias was assessed using Egger's test. Results: We included 41 studies, comprising 359 317 participants, that investigated the effects of dietary patterns on SUA levels (n = 25) and hyperuricemia (n = 19). Our findings suggested that a plant-based dietary pattern was associated with decreased SUA levels in both interventional (standard mean difference: -0.24 mg dL-1, 95% CI: -0.42, -0.06; I2 = 61.4%) and observational studies (odds ratio (OR): 0.92, 95% CI: 0.89, 0.95, I2 = 91.1%); this association was stronger in men (OR: 0.45, 95% CI: 0.35, 0.58; I2 = 0). We observed that plant- and animal-based dietary patterns were associated with a reduced risk (OR: 0.75; 95% CI: 0.67, 0.83, I2 = 93.3%) and an increased risk (OR: 1.38; 95% CI: 1.20, 1.59, I2 = 88.4%) of hyperuricemia, respectively. Conclusions: Collectively, a plant-based dietary pattern is negatively associated with SUA levels and hyperuricemia. Therefore, a plant-based dietary pattern should be recommended for the management of SUA levels and the prevention of hyperuricemia.

Decreased Serum Uric Acid Level as an Indicator of Altered Oxidative Balance in Patients With Migraine.

Migraine is one of the most common neurological diseases. The pathophysiology of migraine has not yet been fully elucidated. There is increasing evidence supporting the relationship between oxidative stress and migraine. This is a retrospective, cross-sectional and observational study. The patients were divided into two groups, episodic migraine and chronic migraine. Episodic migraine patients were divided into two subgroups, migraine with aura and migraine without aura. Serum Albumin, total bilirubin, uric acid levels, and migraine clinical findings were obtained from medical records. A total of 181 participants, 88 patients and 93 controls, were included in the study. Serum albumin levels were lower in the patient group than in the control group, they did not reach statistical significance (p=0.082). There was no significant difference between the patient and control groups for total bilirubin levels (p=0.785). Serum uric acid levels in the patient group were found to be significantly lower than in the control group (p<0.001). Measured levels were similar in chronic and episodic migraine groups, and migraine with aura and migraine without aura subgroups. We thought this oxidative stress marker may be associated with the presence of migraine, but this is not significant for migraine subtypes and migraine progression.

Associations and pathways between residential greenness and hyperuricemia among adults in rural and urban China

BackgroundResidential greenness may decrease the risk for hyperuricemia in rural areas, but the urban-rural disparities in this association and underlying pathways have not been studied. ObjectivesTo investigate the associations and potential pathways between residential greenness and hyperuricemia in urban and rural areas. MethodsThe baseline survey of the China Multi-Ethnic Cohort (CMEC) was used. Hyperuricemia was defined as serum uric acid (SUA) > 417 μmol/L for men and >357 μmol/L for women. The satellite-based normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) were used to capture residential greenness. A propensity score inverse-probability weighting method was used to assess urban-rural differences in the associations between residential greenness and hyperuricemia, with possible mediation effects of physical activity (PA), body mass index (BMI), PM2.5, and NO2 examined by causal mediation analyses. ResultsA total of 72,372 participants were included. The increases in the EVI500m and NDVI500m residential greenness were associated with a decreased risk for hyperuricemia and the SUA level in both urban and rural areas. For example, each 0.1-unit increase in EVI500m was associated with a decreased hyperuricemia risk of 7% (OR = 0.93 [0.91, 0.96]) and a decreased SUA level of −1.77 μmol/L [-2.60, −0.93], respectively; such associations were stronger in urban areas for both the risk for hyperuricemia (OR = 0.84 [0.83, 0.86]) and SUA level (−7.18 μmol/L [-7.91, −6.46]). The subgroup analysis showed that the greenness-hyperuricemia/SUA association varied by age, sex, and annual household income. The percentage of the joint mediation effect of PA, BMI, PM2.5, and NO2 on the association between EVI500m and the risk for hyperuricemia was higher in urban (34.92%) than rural areas (15.40%). BMI, PM2.5, and PA showed significantly independently mediation effects for the greenness-hyperuricemia association in both rural and urban areas. ConclusionsExposure to residential greenness was associated with a decreased risk for hyperuricemia, partially through the pathways of PA, BMI, PM2.5, and NO2, which varied in urban and rural areas.

Comparative efficacy and safety of uricosuric agents in the treatment of gout or hyperuricemia: a systematic review and network meta-analysis.

The current world witnesses a greatly increased prevalence and incidence of hyperuricemia and gout with unfortunately the comparative efficacy and safety of present available uricosuric agents remaining uncertain. We herein aimed to investigate the most appropriate uricosuric agent for gout or hyperuricemia patients. PubMed, Embase, Cochrane Library databases, and ClinicalTrials.gov from inception to 2 July 2022 were searched to retrieve eligible studies assessing efficacy and safety of uricosuric drugs in hyperuricemia or gout patients. Network meta-analysis was carried out using the Stata 16.0 software. Twelve randomized controlled trials comprising 1851 patients were eventually included. Network meta-analysis showed that dotinurad 4mg once daily, verinurad, dotinurad 2mg once daily, dotinurad 1mg once daily, and benzbromarone were the top 5 effective treatments to achieve target serum uric acid. Furthermore, dotinurad 4mg once daily was more effective at achieving urate-lowering targets (RR of dotinurad 4mg once daily vs. probenecid: 1.68, 95% CI [1.13; 2.50]) and safer (RR of probenecid vs. dotinurad 4mg once daily: 1.77, 95% CI [0.69; 4.56]) than probenecid. This network meta-analysis demonstrated an important absolute benefit of dotinurad 4mg once daily to achieve target serum uric acid and low risk of adverse events for drug treatment of gout or hyperuricemia patients. Additionally, verinurad might be used as an alternative uricosuric therapeutic option to dotinurad. These findings provided further comprehensive insight into the treatment value of current uricosuric agents for gout or hyperuricemia. Key Points 1. This is the first systematic review and network meta-analysis examining the efficacy and safety of currently available uricosuric agents in gout or hyperuricemia patients. 2. Recommended doses of dotinurad 4mg once daily used for the treatment of gout or hyperuricemia patients can significantly decrease serum uric acid levels. 3. The present findings will provide further comprehensive insight into the treatment value of certain uricosuric agents for gout or hyperuricemia.