Uric Acid Reduction Research Articles

Safety Profile for Evaluation of Berberine in Sprague- Dawley Rats: Effects on Renal, Liver and Myelopoietic Functions

The study was designed to investigate the effect of berberine toxicity on liver enzymes, renal function, serum uric acid and blood cell counts of Sprague-Dawley rats. For this purpose, twenty Sprague-Dawley rats were divided in two groups. Group A (n=10) was given distilled water and Group B (n=10) wassupplemented berberine hydrochloride with dose of 75 mg/kg body weight/day. 24 weeks post-treatment, blood samples were collected by cardiac puncture from both groups and tested for Hb (%), WBC, RBC and platelet counts, SGPT, alkaline phosphatse, serum uric acid, blood urea and serum creatinine. All thenumerical data were expressed as mean± SD. The values in two groups were analyzed with help of unpaired t-test. A p-value ˂ 0.05 was considered significant. After 24 weeks of treatment with berberine hydrochloride, no significant differences were observed in Hb%, platelet count, liver enzymes and RFTs between twogroups. There was a significant increase in RBC count and reduction in serum uric acid and WBC count in experimental group as compared to control group. There were no significant untoward effects of berberine on platelet count, LFTs and RFTs of Spargue-Dawley rats except neutropenia.

Uric Acid and Diabetic Nephropathy Risk.

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease (ESRD) in the western world. Current treatment methods, with better control of glycemia and blood pressure, including renin-angiotensin system blockade (RASB), appear to have slowed the DN progression rate but have not substantially decreased the annual incidence of new DN ESRD cases. Thus, new treatment targets are needed. Higher levels of serum uric acid (UA) are associated with increased risk of the clinical manifestations of DN in persons with types 1 and 2 diabetes. Also, UA is a strong predictor of DN progression. Two small, short-term, proof-of-concept clinical trials in which a minority of the patients had diabetes suggested that reduction of UA with allopurinol could decrease the rate of glomerular filtration rate (GFR) loss in persons with chronic kidney disease (CKD). However, a definitive trial to check whether UA reduction can benefit DN progression has not been conducted as yet. Preventing Early Renal Loss in Diabetes (PERL) is an ongoing trial in persons with type 1 diabetes and early to moderate GFR reduction. This 3-year randomized placebo controlled trial in 530 subjects is to check whether UA reduction with allopurinol can slow the rate of GFR decline as determined by the plasma disappearance of iohexol. Key Message: If the results of the PERL trial are positive, initiation of UA reduction treatment while GFR is relatively well preserved could delay ESRD in DN by 8-10 years, that is, considerably longer than the period that has been demonstrated for RASB. This could have important implications for the treatment of DN in particular and of CKD in general.

Obesity and serum uric acid in secondary school-age students of srinagarindra the princess mother school, Phayao, Thailand.

Obesity and hyperuricemia are the precipitating factors of multiple disease processes. Studies on the relationship between obesity and hyperuricemia in Thai adolescents are limited. The objective is to investigate the gender differences in obesity and serum uric acid as well as the relationship between obesity and serum uric acid levels in secondary school-age students. A cross-sectional study conducted among 689 secondary school-age students; 313 boys and 376 girls. Body composition and fasting serum uric acid were assessed. This study defined hyperuricemia as serum uric acid >6 mg/dL in girls and >7 mg/dL in boys. By body mass index (BMI) for age and percentage of body fat classification, the prevalences of obesity were 11.5% and 9.0%, respectively. Prevalence of obesity by BMI for age, 15.3% and percentage of body fat, 12.4% in boys were statistically significantly higher than those in girls, 8.2% and 6.1%, respectively. Boys in all age groups had statistically significantly higher serum uric acid levels than those in girls as well as serum uric acid levels at late adolescent period in both sexes were statistically significantly higher than those at early adolescent period. On multivariate analysis, the demographic factors studied showed that boys, late adolescence period, and excess body fat adolescents had higher prevalence of hyperuricemia in secondary school-age students who have their birthplace in 8 provinces of Northern Thailand. This indicated that early nutritional management and encourage obese adolescents to weight and serum uric acid reductions are important for the prevention of diet-related chronic diseases in their adult period.

Physical exercises and weight loss in obese patients help to improve uric acid.

Objectiveto assess the impact of longitudinal change of the overweight and physical activity on hyperuricemia.MethodsWe performed a retrospective cohort study. Demographic information, clinical features, laboratory findings, body weight and physical exercises pattern were documented.ResultsAltogether 4678 cases of hyperuricemia were enrolled. The median aged males were most affected. Individuals in the middle age had the highest prevalence of being overweight (2501/3382, 74.0%). Middle aged with BMI≥25 kg/m2 were more likely to lose weight (963/2807, 34.3%). BMI and waist circumference control helped to reduce serum uric acid. Overweight population was more likely to use urate-lowering or uricosuric medication (3025/3382, 89.4%). Intermediate and heavy activity were associated with bigger SUA improvement. Patients in the age of 35-60 were more likely to do physical exercises than the others.ConclusionBeing overweight is strongly associated with hyperuricemia. Successful weight control was correlated with significant uric acid reduction. Intermediate to heavy physical activity helps to reduce waist circumference and SUA. In the hyperuricemia population, obese, middle aged men were the most affected, and also the most likely to do more exercises and get their bodyweight back to normal.

Favourable Lipid Modulatory And Renal Protective Effects Of Ginger And Fish Oil In Hypercholesterolemic Male Rats

Hypercholesterolemia is one of the most important risk factors for atherosclerosis and subsequent cardiovascular diseases. In the present study, the therapeutic effects of ginger and fish oil supplementation on serum lipid profile and kidney functions in high cholesterol diet-induced hypercholesterolemia in rats have been evaluated. The animals were divided into 4 groups of 12 rats each. Group I served as the control. Rats in groups II, III and IV were fed with an atherogenic diet for 8 weeks, group III received atherogenic diet supplemented with 5% ginger, group IV received atherogenic diet supplemented with 10 % fish oil. The treatment with ginger and fish oil results in significant reduction in elevated serum total cholesterol, triglycerides(TG), low density lipoproteins (LDL) and very low density lipoproteins (VLDL) and elevation in high density lipoproteins (HDL), marked modulation of atherogenic index (AI) has been noted. Also, there was significant reduction in serum urea, uric acid and creatinine levels which was markedly elevated by atherogenic diet. We concluded that dietry supplementation with ginger and/or fish oil have favorable effects on serum lipid parameters and kidney functions in hypercholesterolemic male rats.

Effect of Allopurinol on Inflammatory Markers in Chronic Kidney Disease Patients with Asymptomatic Hyperuricaemia

This was a hospital based prospective, interventional study which included CKD stage 3- 5 patients with higher level of uric acid (male>7mg/dl, female>6mg/dl). The objective of the study was to evaluate the effect of allopurinol on inflammatory markers in patients with chronic kidney disease (stage 3-5) with asymptomatic hyperuricaemia. One hundred and twenty patients were distributed in two groups. Sixty patients were placed in treatment group and sixty in control group. Purposive sampling technique was followed. In the study mean age was 49 (±9) years in treatment group and 45 (±11) years in control groups. Male were predominant in both groups. There were no significant difference in baseline characteristics between treatment group and control group (p>0.05). Sixty patients of treatment group were administered a dose of 100 mg/d of allopurinol. Follow up assessment was done at basally, at 4 months and at 8 month after starting treatment. No significant differences were seen between baseline SBP, DBP, Hb and HbA1c with 4th month and 8th month follow up in both treatment group and control group, but mean Hb was significantly decreased in control group from the baseline after 8 month. No significant change was found in case of mean ESR at 4th and 8th month in any group. But base line mean CRP was significantly reduced in treatment group and increased in control group at 4th and 8th month of follow up. Serum uric acid was decreased in treatment group while it was significantly raised from the base line at 4th month and 8th month in control group. While comparing between two groups results showed means of serum uric acid and CRP were significantly decreased in treatment group compared to control group after 8th month. There was a positive correlation between Uric Acid with CRP level after 8 month of allopurinol treatment although this finding was not statistically significant. So, allopurinol may have a protective role in CKD by decreasing serum uric acid level and reduction of inflammatory response in patients with chronic kidney disease stage 3 - 5 with asymptomatic hyperuricaemia.J Dhaka Medical College, Vol. 26, No.1, April, 2017, Page 12-24

Effects of Sodium Glucose Cotransporter-2 Inhibitors on Serum Uric Acid in Type 2 Diabetes Mellitus.

Hyperuricemia has been linked to metabolic syndrome, cardiovascular disease, and chronic kidney disease. Hyperuricemia and type 2 diabetes mellitus were inter-related, type 2 diabetes mellitus was more at risk of having a higher serum uric acid level, and also individuals with higher serum uric acid had higher risk of developing type 2 diabetes in the future. Insulin resistance seems to play an important role in the causal relationship between metabolic syndrome, type 2 diabetes, and hyperuricemia. Oral diabetic drugs that would have additional beneficial effects on reducing serum uric acid levels are of importance. Selective SGLT2 inhibitors were extensively studied in type 2 diabetes mellitus and were found to have improvement of glycemic control, in addition to their proven metabolic effects on weight and blood pressure. Additional beneficial effect of SGLT2 inhibitors on serum uric acid level reduction is investigated. Recently, data have been accumulating showing that they have additional beneficial effects on serum uric acid reduction. As for the postulated mechanism, serum uric acid decreased in SGLT2 inhibitor users as a result of the increase in the urinary excretion rate of uric acid, due to the inhibition of uric acid reabsorption mediated by the effect of the drug on the GLUT9 isoform 2, located at the collecting duct of the renal tubule.

Lesinurad: what the nephrologist should know.

Lesinurad is an oral inhibitor of the monocarboxylic/urate transporter URAT1 encoded by the SLC22A12 gene. Market authorization was granted in February 2016 in Europe and December 2015 in the USA. As a potentially nephrotoxic uricosuric drug acting on the kidney, nephrologists should become familiar with its indications and safety profile. The approved indication is treatment of gout in combination with a xanthine oxidase (XO) inhibitor in adult patients who have not achieved target serum uric acid levels with an XO inhibitor alone. It is not indicated for asymptomatic hyperuricaemia or for patients with estimated creatinine clearance <45 mL/min. The only authorized daily dose is 200 mg and cannot be exceeded because of the nephrotoxicity risk. Nephrotoxicity is thought to be related to uricosuria. At the 200 mg/day dose, serum creatinine more than doubled in 1.8% of lesinurad patients (versus 0% in placebo) and in 11% of these it was not reversible. In addition, it is subject to a risk management plan given the potential association with cardiovascular events. In randomized clinical trials, the association of lesinurad with either allopurinol or febuxostat achieved a greater reduction in serum uric acid (∼1 mg/dL lower) than the XO inhibitors alone, and this allowed the serum uric acid target to be met in a higher proportion of patients, which was the primary endpoint. However, no clinical differences were observed in gout flares or tophi, although these were not the primary endpoints.

The Effects of Conjugated Linoleic Acid and Berberine Supplementation on Markers of Oxidative Stress in Broiler Chickens

Reactive oxidative species (ROS) are oxygen base molecules that are leaked from the electron transport chain during mitochondrial cellular respiration. They are kept in balance by endogenous and exogenous antioxidants, which may include conjugated linoleic acid (CLA) and a plant root extract called berberine. A redox shift towards oxidants causes a state called oxidative stress, which is detrimental if prolonged. A ten week study examined the effect CLA and berberine supplementation on markers of oxidative stress in broiler birds. Broilers (n=60) were divided into six groups; the diet of group four to six included allopurinol (25mg/kg body weight) which induced an oxidative stress state. Pen 1(P1) served as the control, P2 CLA oil (50% substitution), P3 berberine supplementation (20g/kg feed), P4 allopurinol alone, P5 CLA oil + allopurinol and P6 berberine + allopurinol. Body weight, plasma uric acid as a marker of oxidative stress, blood glucose, lipid peroxidation via TBARs assay of serum, and relative gene expression of five endogenous liver antioxidants were measured during the course of the study. The addition of allopurinol to the diet induced an oxidative stress state when compared to the baseline groups as observed by a significant reduction in plasma uric acid. In P5 and P6 treatment we observed on average a 10 fold increase in the relative mRNA expression of superoxide dismutase 2 and 3 as well as glutathione 3 and 7. Notably, CLA increased the expression of uncoupling protein 34 fold compared to control while the addition of allopurinol blocked these changes; in contrast there was a slight increase in the berberine+allopurinol treatment. No significant changes were measured in blood glucose and TBARS. Despite the increase in mRNA expression of the antioxidants genes, the result of the uric acids assay suggest that at the dosages administered CLA and berberine were not effective in reversing the oxidative stress induced by allopurinol.Support or Funding InformationWVU Hatch

DASH diet and change in serum uric acid over time.

The Dietary Approaches to Stop Hypertension (DASH) diet lowers serum uric acid (SUA) levels compared to the typical American (control) diet. However, the time required for the DASH diet to take effect is unknown. We analyzed data from a parallel arm, randomized-controlled trial in pre-hypertensive or hypertensive adults (N=103), comparing the effects of DASH or a control diet on SUA measured at 30, 60, and 90days. Effects were examined overall and within stratified subgroups based on baseline SUA status (SUA ≥6mg/dL vs <6mg/dL). The mean age of participants was 51.5±9.7years, 55% were women, 75% were black, 42% were obese, and 34% had hypertension. Twenty-four of the 103 (23%) participants had a baseline SUA ≥6mg/dL. Overall, compared to the control, DASH lowered SUA by 0.5mg/dL at 30 and 90days. Among participants with baseline SUA ≥6mg/dL, DASH lowered SUA by 0.8 and 1.0mg/dL at 30 and 90days, respectively. These findings demonstrate that the DASH diet reduces SUA within 30days, with a sustained effect at 90days, which is informative for healthcare providers counseling patients on time course expectations for uric acid reduction in response to dietary modification.

Synthesis and evaluation of hydroxychalcones as multifunctional non-purine xanthine oxidase inhibitors for the treatment of hyperuricemia

A series of hydroxychalcone derivatives have been designed, synthesized and evaluated for human xanthine oxidase (XO) inhibitory activity. Most of the tested compounds acted moderate XO inhibition with IC50 values in the micromolar rang. Molecular docking and kinetic studies have been performed to explain the binding modes of XO with the selected compounds. In addition, in vitro antioxidant screening results indicated that some of the hydroxychalcones possessed good anti-free radical activities. Furthermore, the preferred compounds 16 and 18 were able to significantly inhibit hepatic xanthine oxidase activity and reduced serum uric acid level of hyperuricemic mice in vivo. In summary, compounds 16 and 18 with balanced activities of antioxidant, XO inhibition and serum uric acid reduction, which are promising candidates for the treatment of hyperuricemia and gout.

Can allopurinol improve retinopathy in diabetic rats? Oxidative stress or uric acid; which one is the culprit?

Allopurinol, an inhibitor of xanthine oxidase, reduces both plasma uric acid and oxidative stress and shows useful effects on some complications of diabetes. However, it is not defined which of the above mentioned properties are involved. Moreover, to the best of our knowledge no study has been done on the effects of allopurinol on diabetic retinopathy. In the present study, the effect of allopurinol on experimental diabetic retinopathy and its possible mechanism has been investigated. Thirty two rats were divided into four groups of eight rats each; (1) normal, (2) diabetic control, (3) diabetic + allopurinol (50 mg/kg.day), (4) diabetic + benzbromarone (10 mg/kg.day). Drugs were administered daily and orally from the day after diabetes induction for eight weeks. Thereafter retinal function and structure were evaluated by electroretinography and microscopic studies. Uric acid and oxidative stress biomarkers were measured biochemically. Diabetes significantly increased plasma uric acid and oxidative stress markers and reduced body weight and amplitude of electroretinogram (ERG) b-wave and oscillatory potentials. Treatment of diabetic rats with allopurinol caused a significant increase in the amplitude of ERG b-wave (87%) and decrease in blood sugar (20%), uric acid (49%), and 8-iso-prostaglandin F2a (56%), but had no effect on the number of retinal ganglionic cells and oscillatory potentials. Benzbromarone showed no significant effects on the considered parameters except the reduction of uric acid. Allopurinol improved the b-wave amplitude of diabetic rats. It seems that this beneficial effect is due to the reduction of oxidative stress rather than its effect on plasma uric acid.

Metadichol® and Vitamin C Increase In Vivo, an Open-Label Study

Vitamin C, also known as ascorbic acid, is a water-soluble antioxidant. Today we meet our requirements of vitamin C through consumption of fruits and vegetables or by supplementation. Homo sapiens cannot produce vitamin C like many other species that can convert glucose to vitamin C. The gene for enzyme production is dormant in humans. The gene, GULO, that we all carry converts glucose to Vitamin C. in other species but not in humans and primates. The open-label study showed Metadichol® raised levels of vitamin C by 3 fold, endogenously without supplementation of Vitamin C. Possible mechanisms for the increased Vitamin C levels through antioxidant pathways are presented. Metadichol® [1] is a nano-formulation of long chain alcohols derived from sugar cane. In addition to increased Vitamin C levels reduction in Potassium and uric acid, and decreased blood pressure and improvement in quality of life issues were also observed.

The optimal single-dose regimen of rasburicase for management of tumour lysis syndrome in children and adults: a systematic review and meta-analysis.

To perform a meta-analysis exploring the optimal single-dose regimen for managing tumour lysis syndrome (TLS) in children and adults with haematological malignancies. We systematically searched PubMed, MEDLINE, Web of Science, the Cochrane Library and the ClinicalTrials.gov website for studies regarding single-dose rasburicase in paediatric and adult patients with TLS. Data were analysed using Open MetaAnalyst statistical software. Fifteen adult studies (fourteen retrospective studies and one randomized controlled trial) and four observational studies using children were extracted, with a total of 906 and 92 subjects, respectively. Single doses of 1·5, 3, 4·5, 6, 7·5 mg and weight-based single doses of 0·05 and 0·15 mg/kg were compared. The response rate for 6, 7·5 mg and 0·15 mg/kg single doses was 90% (95% CI: 0·825-0·974), 98·6% (95% CI: 0·957-1·015) and 93·6% (95% CI: 0·864-1·007), respectively, and higher than other dosing regimens tested. The single doses of 6 mg and 0·15 mg/kg rasburicase decreased uric acid levels more than the other regimens, and the mean uric acid reduction was 8·45 mg/dL (95% CI, 7·51-9·38) and 10 mg/dL (95% CI, 8·58-11·42), respectively. Our meta-analysis revealed that, for adult patients, a single 6 mg rasburicase dose is sufficient to normalize and sustain lower uric acid and creatinine levels in adults with TLS. This dose, therefore, balances cost and efficacy of treatment. The 3- and 4·5-mg single dose can be considered if the baseline uric acid level <12 mg/dL, with close monitoring of clinical and biochemical parameters, and repeat dosing if required. The 1·5 mg and 0·15 mg/kg single dose were sufficient to manage TLS in children.

Patients Attending Shared Medical Appointments for Metabolic Stone Prevention Have Decreased Stone Risk Factors.

Shared medical appointments (SMAs) have decreased patients' wait time to initial stone clinic appointment, standardized education, and increased exposure to nutrition therapy. We assessed the effectiveness of SMAs in reducing patients' urinary stone risk factors. Patients who established care in our stone clinic in an SMA between March 2012 and August 2015 were sequentially identified. After eliminating those without follow-up urine collections or whose urinary creatinine excretion between the two collections varied by >40%, 113 patients were included (M:F 63:50; 54 ± 15 years; body mass index [BMI] 30.6 ± 6.7). Results from before and after the SMA were compared with those from a similar cohort of patients who attended individual patient appointments (IPAs) for their first stone clinic visit (n = 63; M:F 37:26; 54 ± 14 years; BMI 30.1 ± 8.2). All patients received individualized medical therapy for stone prevention. After medical and nutritional therapy, SMA patients with elevated risk(s) at baseline achieved significant reductions in uric acid, calcium, and sodium; p ≤ 0.001 for all. Those with low urine magnesium, low urine volume, low urine pH, and/or low urine citrate at baseline achieved increases; p ≤ 0.0008 for all. IPA patients with elevated baseline risk factors achieved reductions in oxalate and uric acid (p ≤ 0.004 for both) but neither calcium nor sodium and an increase in citrate (p = 0.003) but not magnesium. Patients from SMAs reduced their stone recurrence risk and compared favorably with patients from IPAs. Contributing factors may include shorter time from stone event to appointment and more standardized education for patients attending SMAs.

SGLT2 Inhibitors: Benefit/Risk Balance.

Inhibitors of sodium-glucose cotransporters type 2 (SGLT2) reduce hyperglycemia by increasing urinary glucose excretion. They have been evaluated in patients with type 2 diabetes treated with diet/exercise, metformin, dual oral therapy or insulin. Three agents are available in Europe and the USA (canagliflozin, dapagliflozin, empagliflozin) and others are commercialized in Japan or in clinical development. SGLT2 inhibitors reduce glycated hemoglobin, with a minimal risk of hypoglycemia. They exert favorable effects beyond glucose control with consistent body weight, blood pressure, and serum uric acid reductions. Empagliflozin showed remarkable reductions in cardiovascular/all-cause mortality and in hospitalization for heart failure in patients with previous cardiovascular disease. Positive renal outcomeswere also shown with empagliflozin. Mostly reported adverse events are genital mycotic infections, while urinary tract infections and events linked to volume depletion are rather rare. Concern about a risk of ketoacidosis and bone fractures has been recently raised, which deserves caution and further evaluation.

Effects of xanthine oxidase inhibition with febuxostat on the development of nephropathy in experimental type 2 diabetes.

Elevated serum uric acid (UA) is a risk factor for the development of kidney disease. Inhibitors of xanthine oxidase (XOi), an enzyme involved in UA synthesis, have protective effects at early stages of experimental diabetic nephropathy (DN). However, long-term effects of XOi in models of DN remain to be determined. The development of albuminuria, renal structure and molecular markers of DN were studied in type 2 diabetic Zucker obese (ZO) rats treated for 18weeks with the XOi febuxostat and compared with vehicle-treated ZO rats, ZO rats treated with enalapril or a combination of both agents, and lean Zucker rats without metabolic defects. Febuxostat normalized serum UA and attenuated the development of albuminuria, renal structural changes, with no significant effects on BP, metabolic control or systemic markers of oxidative stress (OS). Most of these actions were comparable with those of enalapril. Combination treatment induced marked decreases in BP and was more effective in ameliorating structural changes, expression of profibrotic genes and systemic OS than either monotherapy. Febuxostat attenuated renal protein expression of TGF-ß, CTGF, collagen 4, mesenchymal markers (FSP1 and vimentin) and a tissue marker of OS nitrotyrosine. Moreover, febuxostat attenuated TGF-ß- and S100B-induced increased expression of fibrogenic molecules in renal tubular cells in vitro in UA-free media in an Akt kinase-dependent manner. Febuxostat is protective and enhances the actions of enalapril in experimental DN. Multiple mechanisms might be involved, such as a reduction of UA, renal OS and inhibition of profibrotic signalling.

Impact of Febuxostat on Renal Function in Gout Patients With Moderate‐to‐Severe Renal Impairment

Renal impairment is a risk factor for gout and a barrier to optimal gout management. We undertook this exploratory study to obtain data that have been heretofore limited regarding the safety and efficacy of febuxostat in patients with moderate-to-severe renal impairment (estimated glomerular filtration rate [GFR] 15-50 ml/minute/1.73 m(2) ). Ninety-six gout patients with moderate-to-severe renal impairment were enrolled in a 12-month multicenter, randomized, double-blind, placebo-controlled study. Patients were randomly assigned at a 1:1:1 ratio to receive 30 mg febuxostat twice daily, 40/80 mg febuxostat once daily, or placebo. The primary efficacy end point was the change in serum creatinine (Cr) level from baseline to month 12. Secondary end points included the change in estimated GFR from baseline to month 12 and the proportion of patients with a serum uric acid (UA) level of <6.0 mg/dl at month 12. At month 12, there were no significant differences in the change in serum Cr level from baseline, or in the change in estimated GFR from baseline, in either febuxostat group compared to the placebo group. The proportion of patients with a serum UA level of <6.0 mg/dl at month 12 was significantly greater in both febuxostat groups compared to the placebo group (both P < 0.001). At least 1 treatment-emergent adverse event (TEAE) occurred in 78.1% of patients receiving 30 mg febuxostat twice daily, 87.5% of patients receiving 40/80 mg febuxostat once daily, and 78.1% of patients receiving placebo. TEAEs most frequently involved the categories of renal failure and impairment and renal function analyses. Febuxostat proved to be efficacious in serum UA reduction and was well tolerated in gout patients with moderate-to-severe renal impairment. Patients randomly assigned to receive febuxostat demonstrated significantly lower serum UA levels and no significant deterioration in renal function.

Comparison of Serum Uric Acid Concentrations in Subjects With and Without Atrial Fibrillation

Background: Uric acid, a product of purine degradation, is a risk factor for cardiovascular disease. Studies have demonstrated a relationship between uric acid and increased inflammatory and oxidative stress in the general population. Recent studies also confirmed the role of inflammatory factors and oxidative stress in atrial fibrillation (AF). Objectives: The purpose of this study was to investigate the relationship between serum uric acid levels and the risk of AF. Patients and Methods: This case-control study consisted of 32 patients with AF and 32 healthy controls. Both groups were matched by age, sex, and underlying disease. The diagnosis of AF was based on an electrocardiogram and confirmed by a cardiologist. Patients with heart failure, coronary artery disease, recent infection, renal failure, thyroid disorders and malignancy or who were treated with drugs affecting serum uric acid were excluded. The uric acid levels in both groups were measured using an enzymatic method. The mean serum uric acid of the two groups was compared with a t-test and SPSS software. Results: The female to male ratio in the two groups was 1.28. The mean age of the patients in the AF group and control group was 69.12 ± 11.8 and 67.75 ± 14.8, respectively. There were no significant differences in the age and sex of the two groups. The mean serum uric acid in the AF group and control group was significantly different (5.79 ± 1.19 mg/dL and 4.81 ± 1.26 mg/dL, respectively; P = 0.002). Conclusions: The results suggest that serum uric acid can be considered a risk factor for AF. Further studies are recommended to investigate the role of uric acid reduction in the prevention and treatment of AF.

Miracle Fruit (Synsepalum dulcificum) Exhibits as a Novel Anti-Hyperuricaemia Agent.

Miracle fruit (Synsepalum dulcificum) belongs to the Sapotaceae family. It can change flavors on taste buds, transforming acidic tastes to sweet. We evaluated various miracle fruit extracts, including water, butanol, ethyl acetate (EA), and hexane fractions, to determine its antioxidant effects. These extracts isolated from miracle fruit exerted potential for reduction of uric acid and inhibited xanthine oxidase activity in vitro and in monosodiumurate (MSU)-treated RAW264.7 macrophages. Moreover, we also found that the butanol extracts of miracle fruit attenuated oxonic acid potassium salt-induced hyperuricaemia in ICR mice by lowering serum uric acid levels and activating hepatic xanthine oxidase. These effects were equal to those of allopurinol, suggesting that the butanol extract of miracle fruit could be developed as a novel anti-hyperuricaemia agent or health food.