The management of gout

Chemo-Enzymatic Generation of Highly Fluorescent Nucleoside Analogs Using Purine-Nucleoside Phosphorylase

Chemo-enzymatic syntheses of strongly fluorescent nucleoside analogs, potentially applicable in analytical biochemistry and cell biology are reviewed. The syntheses and properties of fluorescent ribofuranosides of several purine, 8-azapurine, and etheno-purine derivatives, obtained using various types of purine nucleoside phosphorylase (PNP) as catalysts, as well as α-ribose-1-phosphate (r1P) as a second substrate, are described. In several instances, the ribosylation sites are different to the canonical purine N9. Some of the obtained ribosides show fluorescence yields close to 100%. Possible applications of the new analogs include assays of PNP, nucleoside hydrolases, and other enzyme activities both in vitro and within living cells using fluorescence microscopy.

Anti-gouty arthritis and anti-inflammatory effects of curcumin nanoparticles in monosodium urate crystals induced Balb/C mice

Gout is a metabolic condition characterized by the accumulation of urate crystals in the synovial joints. These crystal depositions result in joint swelling and increased concentration of serum uric acid in blood. The commercially available drugs lower serum uric acid levels and reduce inflammation, but these standard therapies have many side effects. This study aimed to investigate anti-gout and anti-inflammatory properties of curcumin nanoparticles (CNPs). For this purpose, CNPs were prepared by dissolving curcumin into dichloromethane. Then, gout was induced by injecting monosodium urate crystals (MSU) in the ankle joint and in the intra-peritoneal cavity which caused ankle swelling and increased blood uric acid levels. CNPs in different concentrations (5, 10, and 20 ppm) and allopurinol were orally administered. The MSU crystals increased the xanthine oxidase levels both in serum and the liver. Moreover, MSU crystals increased the serum levels of interleukin 1β, interleukin-6, tumor necrosis factor-alpha, liver function tests markers, renal function tests markers, and lipid profiles. However, the administration of CNPs decreased the levels of all these variables. CNPs increased the serum high-density lipoprotein and interleukin-10 levels. Moreover, CNPs also reduced ankle swelling significantly. Hence, the levels of xanthine oxidase, uric acid and ankle swelling were reduced significantly by oral administration of CNPs. Our findings indicate that CNPs through their anti-inflammatory properties significantly alleviate gouty arthritis. Thus, the study concluded that CNPs can be developed as an efficient anti-gout agent with minimal side effects.

Prevalence and risk factors for hyperuricemia and hyperuricosuria in patients with hematologic malignancies

Introduction

Hyperuricemia is a common complication of hematologic malignancies, and hyperuricosuria in this population has shown conflicting results. This study aimed to determine the prevalence of hyperuricemia and parameters associated with serum uric acid (SUA) and urine uric acid (UUA) in patients with lymphoma and myeloproliferative neoplasms (MPN).

Methods

This cross-sectional study included adult patients with newly diagnosed lymphoma and MPN at the university-based hospital. Clinical characteristics were collected, and independent risk factors for hyperuricemia and hyperuricosuria were determined using multiple logistic regression.

Results

One hundred and sixty-five patients were included with a median age of 55 years (45.5-64) and 51.5% were males. There were 91 patients (55.2%) with lymphoma and 74 cases (44.8%) of MPN. Overall, hyperuricemia was prevalent in 43.6% with a median SUA of 6.3 mg/dl (4.6-8) and hyperuricosuria was detected in 39.4% with a median 24-h UUA of 545 mg (365.4-991). Hyperuricemia was observed in patients with lymphoma and MPN in 20.9% and 71.6%, respectively, and hyperuricosuria in 15.4% and 68.9%, respectively. In lymphoma patients, estimated glomerular filtration rate (eGFR) <90 ml/min/1.73 m2 and serum lactate dehydrogenase (LDH) ≥ 250 U/L were associated with hyperuricemia with odds ratio (OR) 3.24, 95% confidence interval (CI) 1.95-11.07, p = 0.006 and OR 2.07, 95%CI 1.62-6.97, p = 0.039), and only elevated serum LDH was related to hyperuricosuria (OR 2.37, 95%CI 1.56-14.29, p = 0.036). In MPN patients, hemoglobin levels <10 g/dl and serum LDH ≥ 640 mg/dl were independent risk factors of hyperuricosuria (OR 1.88, 95%CI 1.42-8.39, p = 0.045 and OR 6.21, 95%CI 1.49-25.74, p = 0.012).

Conclusion

Hyperuricemia in patients with hematologic malignancies was common, notably MPN, and parameters associated with hyperuricosuria were provided. In addition to the utilization of allopurinol in patients at high risk of tumor lysis syndrome, patients without hyperuricosuria may also be of significant interest.

Sanmiao wan alleviates inflammation and exhibits hypouricemic effect in an acute gouty arthritis rat model

ETHNOPHARMACOLOGICAL RELEVANCE

Sanmiao wan (SMW), a classical traditional Chinese medicine (TCM) formula, has been employed to treat gouty diseases in clinic as early as Yuan dynasty. It shows remarkably therapeutic effects in acute gouty arthritis (GA). However, the potential mechanisms of SMW are still not fully revealed.

AIM OF THE STUDY

The objective of this project is to evaluate the pharmacological effects and possible mechanisms of SMW in a rat model of acute GA.

MATERIALS AND METHODS

Monosodium urate (MSU) suspension was injected into the ankle joint of rats to establish acute GA model. The inflammation was evaluated by measuring the posterior ankle diameter. The pathological status of synovial tissue was assessed by hematoxylin eosin (HE), Masson, and picrosirius red staining. The level of IL-6 was measured using ELISA kit. The levels of blood urea nitrogen (BUN), creatinine (CR), UA (uric acid), and xanthine oxidase (XOD) in the serum were measured using standard diagnostic kits. The percentage of Th17 cells in blood samples was performed using flow cytometry. Moreover, RT-qPCR was performed to examine the mRNA level of RANK, RORγt, RANKL, and STAT3 in the synovial tissue. Furthermore, immunofluorescence was carried out to assess the expression of STAT3 in the synovial tissue.

RESULTS

SMW effectively alleviated the inflammation and improved the pathological status of the ankle joint in rats with acute GA. It significantly suppressed the release of proinflammatory cytokine (IL-6). Meanwhile, the levels of UA, BUN, and CR were markedly reduced after SMW treatment. A remarkable reduction of XOD activity was observed in the study. Importantly, SMW treatment significantly reduced the frequency of Th17 cells, decreased the mRNA levels of RANK, RORγt, RANKL, and STAT3 in the synovial tissue. Furthermore, the suppression of STAT3 was also demonstrated using immunofluorescence in SMW-treated group.

CONCLUSION

SMW showed significant anti-inflammatory and hypouricemic effects in a rat model of GA. It is an effective TCM formula for GA therapy.

Pathophysiology and Treatment of Gout Arthritis; including Gout Arthritis of Hip Joint: A Literature Review

Gout is triggered by the accumulation of uric acid in the body, leading to hyperuricemia. Genetic, metabolic, and environmental factors can influence this condition. Excessive uric acid buildup results in the formation of monosodium urate (MSU) crystals, which precipitate in specific areas of the body, including the joints, where they can cause symptoms of gout. While the acute and chronic symptoms of gout have been well-documented, diagnosis of gout affecting the hip joint poses significant challenges. The global incidence of gout, the most prevalent form of inflammatory arthritis, is on the rise. Evaluation of the clinical signs, laboratory results, and imaging results is generally required for diagnosis of gout in cases where MSU crystals have not been detected. Hyperuricemia is considered a primary cause of arthritis symptoms, and comprehensive guidelines for treatment are available. Therefore, the choice of medication is straightforward, and moderate effectiveness of treatment has been demonstrated. Gout is a chronic disease, requiring lifelong uric acid-lowering medications, thus application of a treatment strategy based on the target blood uric acid concentration is necessary. Consequently, cases of gout will likely be observed more frequently by hip surgeons in clinical scenarios in the future. The objective of this review is to provide an overview of the pathophysiology of gout and subsequently examine recent advances in diagnostic methods and therapeutic agents based on an understanding of its underlying mechanisms. In addition, literature on gout-related issues affecting the hip joint, providing a useful reference for hip surgeons is examined.

In-vitro antigout potential of Alstonia scholaris flower, characterization and prospective ligand-receptor interaction of bioactive lead compound

Gout is an arthropathic and inflammatory disease. The prevalence and incidence of such disease has risen in last decades. It is associated with life style thus it could be recognize as life style diseases. In the present study, the flower extract of Alstonia scholaris Linn R.Br., Flower was initially subjected to extraction, isolation which leads to purification of pure eight compounds. All these compounds were identified using various spectroscopic techniques. In-vitro Xanthine oxidase inhibition activity was performed to determine the antigout potential of lead compounds. Compound 8 showed significant activity among all i.e. 14.7 ± 0.43 as compare to standard allopurinol 6.77 ± 0.26. Accordingly, in-silico studies using Autodock vina 4 showed the ligand-protein interaction of luteolin with 3AX7. The docking simulations showed significant binding pocket sites of respective proteins 3AX7 with the least binding energy -10.2 kcal/mol. Consequently, molecular docking simulations for 100ns indicated robust evidence with their conformational structural interaction which serve as active sites for Lead compound. Principal Component Analysis indicated first three PCs capture 23.8%, 39%, and 49% of structural variance in protein. Therefore compound 8 could be consider for potential drug design and development in gout therapy.

Biomineralized Nanoscavenger Abrogates Proinflammatory Macrophage Polarization and Induces Neutrophil Clearance through Reverse Migration during Gouty Arthritis

The deposition of monosodium urate (MSU) crystals induces the overexpression of reactive oxygen species (ROS) and proinflammatory cytokines in residential macrophages, further promoting the infiltration of inflammatory leukocytes in the joints of gouty arthritis. Herein, a peroxidase-mimicking nanoscavenger was developed by forming manganese dioxide over albumin nanoparticles loaded with an anti-inflammatory drug, indomethacin (BIM), to block the secretion of ROS and COX2-induced proinflammatory cytokines in the MSU-induced gouty arthritis model. In the MSU-induced arthritis mouse model, the BIM nanoparticles alleviated joint swelling, which is attributed to the abrogation of ROS and inflammatory cytokine secretions from proinflammatory macrophages that induces neutrophil infiltration and fluid building up in the inflammation site. Further, the BIM nanoparticle treatment reduced the influx of macrophages and neutrophils in the injured region by blocking migration and inducing reverse migration in the zebrafish larva tail amputation model as well as in MSU-induced peritonitis and air pouch mouse models. Overall, the current strategy of employing biomineralized nanoscavengers for arthritis demonstrates clinical significance in dual blocking of peroxides and COX2 to prevent influx of inflammatory cells into the sites of inflammation.

Serum uric acid levels and the risk of diabetes mellitus in premenopausal and postmenopausal women: the Suita study

OBJECTIVE

The association between serum uric acid levels and the risk of diabetes mellitus in women stratified by menopausal status is not well-established. Therefore, we investigated this association among a cohort of Japanese urban women.

METHODS

We conducted a prospective cohort study on 3,304 women (1,252 premenopausal and 2,052 postmenopausal), aged 30 to 79 years, with no prior cardiovascular disease or diabetes mellitus, and enrolled from a general urban population. Cox proportional hazard model was used to calculate hazard ratios and 95% confidence intervals (CIs) for incident diabetes mellitus according to serum uric acid quartiles.

RESULTS

During 13.8 years of median follow-up, 219 incident diabetes mellitus cases were diagnosed. The incidence rate per 1,000 person-years was 3.42 in premenopausal women and 6.19 in postmenopausal women. After adjustment for potential risk factors, the multivariable hazard ratios (95% CIs) of the highest versus lowest serum uric acid quartiles were 1.56 (0.77-3.16) in premenopausal women, 2.00 (1.19-3.34) in postmenopausal women, and 1.81 (1.21-2.73) in all women. The interaction based on menopausal status was not significant ( P = 0.872). The corresponding population attributable fractions (95% CIs) were 13.3% (-8.9% to 31.1%), 19.1% (5.3%-30.9%), and 17.0% (5.6%-27.0%), respectively.

CONCLUSIONS

Serum uric acid levels were positively associated with the risk of diabetes mellitus in postmenopausal women, but not in premenopausal women. However, the lack of an association in premenopausal women may have been due to limited power, so further research is required to confirm this menopausal status-specific association.

Colchicine Does Not Reduce Abdominal Aortic Aneurysm Growth in a Mouse Model

Background and Aims

The nacht domain, leucine-rich repeat, and pyrin domain-containing protein 3 (NLRP3) inflammasome is upregulated in human abdominal aortic aneurysm (AAA), but its pathogenic role is unclear. The aims of this study were firstly to examine whether the inflammasome was upregulated in a mouse model of AAA and secondly to test whether the inflammasome inhibitor colchicine limited AAA growth.

Methods

AAA was induced in eight-week-old male C57BL6/J mice with topical application of elastase to the infrarenal aorta and oral 3-aminopropionitrile (E-BAPN). For aim one, inflammasome activation, abdominal aortic diameter, and rupture were compared between mice with AAA and sham controls. For aim two, 3 weeks after AAA induction, mice were randomly allocated to receive colchicine (n = 28, 0.2 mg/kg/d) or vehicle control (n = 29). The primary outcome was the rate of maximum aortic diameter increase measured by ultrasound over 13 weeks.

Results

There was upregulation of NLRP3 markers interleukin- (IL-) 1β (median, IQR; 15.67, 7.11-22.60 pg/mg protein versus 6.87, 4.54-11.60 pg/mg protein, p = .048) and caspase-1 (109, 83-155 relative luminosity units (RLU) versus 45, 38-65 RLU, p < .001) in AAA samples compared to controls. Aortic diameter increase over 80 days (mean difference, MD, 4.3 mm, 95% CI 3.3, 5.3, p < .001) was significantly greater in mice in which aneurysms were induced compared to sham controls. Colchicine did not significantly limit aortic diameter increase over 80 days (MD -0.1 mm, 95% CI -1.1, 0.86, p = .922).

Conclusions

The inflammasome was activated in this mouse model of AAA; however, daily oral administration of colchicine did not limit AAA growth.

Racial and Sex Disparities in Gout Prevalence Among US Adults

IMPORTANCE

Emerging data suggest gout and hyperuricemia may now be more frequent among Black adults in the US than White adults, especially Black women. However, national-level, sex-specific general population data on racial differences in gout prevalence and potential socioclinical risk factors are lacking.

OBJECTIVE

To identify sex-specific factors driving disparities between Black and White adults in contemporary gout prevalence in the US general population.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional analysis used nationally representative, decadal survey data from successive cycles of the National Health and Nutrition Examination Survey from 2007 to 2016. Data were analyzed from November 1, 2019, through May 31, 2021. Participants included US adults self-reporting Black or White race.

EXPOSURES

Self-reported race, excess body mass index, chronic kidney disease (CKD; defined as estimated glomerular filtration rate <60 mL/min/1.73 m2, according to latest equations without race coefficient), poverty, poor-quality diet, low educational level, alcohol consumption, and diuretic use.

MAIN OUTCOMES AND MEASURES

Race- and sex-specific prevalence of physician- or clinician-diagnosed gout and hyperuricemia and their differences before and after adjusting for potential socioclinical risk factors.

RESULTS

A total of 18 693 participants were included in the analysis, consisting of 3304 Black women (mean [SD] age, 44.8 [0.4] years), 6195 White women (mean [SD] age, 49.8 [0.3] years), 3085 Black men (mean [SD] age, 43.6 [0.5] years]), and 6109 White men (mean [SD] age, 48.2 [0.3] years). Age-standardized prevalence of gout was 3.5% (95% CI, 2.7%-4.3%) in Black women and 2.0% (95% CI, 1.5%-2.5%) in White women (age-adjusted odds ratio [OR], 1.81 [95% CI, 1.29-2.53]); prevalence was 7.0% (95% CI, 6.2%-7.9%) in Black men and 5.4% (95% CI, 4.7%-6.2%) in White men (age-adjusted OR, 1.26 [95% CI, 1.02-1.55]). These associations attenuated after adjusting for poverty, diet, body mass index, and CKD among women and for diet and CKD among men but became null after adjusting for all risk factors (ORs, 1.05 [95% CI, 0.67-1.65] among women and 1.05 [95% CI, 0.80-1.35] among men). Hyperuricemia end point findings were similar.

CONCLUSIONS AND RELEVANCE

In this nationally representative race- and sex-specific cross-sectional study of US adults, gout was more prevalent in adults self-reporting Black race during a recent 10-year period compared with their White counterparts. These racial differences may be explained by sex-specific differences in diet and social determinants of health and clinical factors. Culturally informed efforts focusing on these factors could reduce current gout-related disparities.

Treatment Guidelines in Gout

The range of drug treatment options to treat acute and chronic gout has changed dramatically over the last 20 years. Yet, there is general consensus that drug therapy selection, dosing and dose titration, of both traditional and novel agents is far from optimally delivered in clinical practice. Updated guidelines disseminated in the last 5 years, from the American College of Physicians, the European League Against Rheumatism, and the American College of Rheumatology, provide clear guidance to the medical community on how and when to optimally integrate these therapeutic options into practice to improve the medical management of gout.

Therapeutic potential of colchicine in cardiovascular medicine: a pharmacological review

Colchicine is an ancient herbal drug derived from Colchicum autumnale. It was first used to treat familial Mediterranean fever and gout. Based on its unique efficacy as an anti-inflammatory agent, colchicine has been used in the therapy of cardiovascular diseases including coronary artery disease, atherosclerosis, recurrent pericarditis, vascular restenosis, heart failure, and myocardial infarction. More recently, colchicine has also shown therapeutic efficacy in alleviating cardiovascular complications of COVID-19. COLCOT and LoDoCo2 are two milestone clinical trials that confirm the curative effect of long-term administration of colchicine in reducing the incidence of cardiovascular events in patients with coronary artery disease. There is growing interest in studying the anti-inflammatory mechanisms of colchicine. The anti-inflammatory action of colchicine is mediated mainly through inhibiting the assembly of microtubules. At the cellular level, colchicine inhibits the following: (1) endothelial cell dysfunction and inflammation; (2) smooth muscle cell proliferation and migration; (3) macrophage chemotaxis, migration, and adhesion; (4) platelet activation. At the molecular level, colchicine reduces proinflammatory cytokine release and inhibits NF-κB signaling and NLRP3 inflammasome activation. In this review, we summarize the current clinical trials with proven curative effect of colchicine in treating cardiovascular diseases. We also systematically discuss the mechanisms of colchicine action in cardiovascular therapeutics. Altogether, colchicine, a bioactive constituent from an ancient medicinal herb, exerts unique anti-inflammatory effects and prominent cardiovascular actions, and will charter a new page in cardiovascular medicine.

Formulation and Characterization of Febuxostat Loaded Nanostructured Lipid Carriers (NLCs) - Gel for Topical Treatment of Gout

BACKGROUND

The aim of the present study was to formulate and characterize Nano- Structured Lipid Carriers (NLCs) of Febuxostat (FB) incorporated in the gel for the treatment of Gout. FB is a Xanthine Oxidase (XO) inhibitor drug used for chronic Gout and hyperuricemia. FB is a BCS class II drug, therefore, water solubility is very poor, and due to its poor solubility and wettability, it leads to poor dissolution. The hot high-pressure homogenization technique was used in this study to improve the physicochemical property of FB.

METHODS

The carbopol 934 was used to prepare NLCs gel of FB. The NLCs of FB was prepared in different drug: polymer ratios w/w (2:1), (1:1), (1:2), (1:3) and (1:4) with solid lipid (Stearic Acid) and liquid lipid (Oleic acid). The preformulation study of FB included FTIR study melting point, standard calibration curves, and drug-polymer interaction study.

RESULTS

The NLCs (1:3) showed high entrapment and drug content. The NLCs gel formulation was 87% released within 6 hours in a controlled manner.

CONCLUSION

NLCs gel modifies the drug release, increases the bioavailability, and reduces side effects of FB. The prepared gel is the efficient formulation for the better treatment of chronic gout and hyperuricemia. The research findings have shown the undesirable side effects associated with the oral route that can be reduced by the use of NLCs formulation through the transdermal route in an effective manner.

Impact of adiposity on risk of female gout among those genetically predisposed: sex-specific prospective cohort study findings over >32 years

OBJECTIVES

To evaluate the joint (combined) association of excess adiposity and genetic predisposition with the risk of incident female gout, and compare to their male counterparts; and determine the proportion attributable to body mass index (BMI) only, genetic risk score (GRS) only, and to their interaction.

METHODS

We prospectively investigated potential gene-BMI interactions in 18 244 women from the Nurses' Health Study and compared with 10 888 men from the Health Professionals Follow-Up Study. GRS for hyperuricaemia was derived from 114 common urate-associated single nucleotide polymorphisms.

RESULTS

Multivariable relative risk (RR) for female gout was 1.49 (95% CI 1.42 to 1.56) per 5 kg/m² increment of BMI and 1.43 (1.35 to 1.52) per SD increment in the GRS. For their joint association of BMI and GRS, RR was 2.18 (2.03 to 2.36), more than the sum of each individual factor, indicating significant interaction on an additive scale (p for interaction <0.001). The attributable proportions of joint effect for female gout were 42% (37% to 46%) to adiposity, 37% (32% to 42%) to genetic predisposition and 22% (16% to 28%) to their interaction. Additive interaction among men was smaller although still significant (p interaction 0.002, p for heterogeneity 0.04 between women and men), and attributable proportion of joint effect was 14% (6% to 22%).

CONCLUSIONS

While excess adiposity and genetic predisposition both are strongly associated with a higher risk of gout, the excess risk of both combined was higher than the sum of each, particularly among women.

Association between the use of allopurinol and risk of increased thyroid-stimulating hormone level

Allopurinol is the first-line agent for patients with gout, including those with moderate-to-severe chronic kidney disease. However, increased thyroid-stimulating hormone (TSH) levels are observed in patients with long-term allopurinol treatment. This large-scale, nested case-control, retrospective observational study analysed the association between allopurinol use and increased TSH levels. A common data model based on an electronic medical record database of 19,200,973 patients from seven hospitals between January 1997 and September 2020 was used. Individuals aged > 19 years in South Korea with at least one record of a blood TSH test were included. Data of 59,307 cases with TSH levels > 4.5 mIU/L and 236,508 controls matched for sex, age (± 5), and cohort registration date (± 30 days) were analysed. An association between the risk of increased TSH and allopurinol use in participants from five hospitals was observed. A meta-analysis (I² = 0) showed that the OR was 1.51 (95% confidence interval: 1.32-1.72) in both the fixed and random effects models. The allopurinol intake group demonstrated that increased TSH did not significantly affect free thyroxine and thyroxine levels. After the index date, some diseases were likely to occur in patients with subclinical hypothyroidism and hypothyroidism. Allopurinol administration may induce subclinical hypothyroidism.

Dietary Acid Load Is Positively Associated with the Incidence of Hyperuricemia in Middle-Aged and Older Korean Adults: Findings from the Korean Genome and Epidemiology Study

Hyperuricemia has been associated with a number of chronic diseases, such as type 2 diabetes mellitus, hypertension, and cardiovascular diseases. Dietary acid load plays a key role in regulating uric acid levels. We hypothesized that potential renal acid load (PRAL) and net endogenous acid production (NEAP) score would be positively associated with the incidence of hyperuricemia. Data from the Health Examinees study, a part of the Korean Genome and Epidemiology Study were used. The PRAL and NEAP scores were calculated to evaluate the dietary acid load. Hyperuricemia was defined as follows: >7.0 mg/dL and >6.0 mg/dL of serum uric acid levels in men and women, respectively. Multivariable Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of hyperuricemia. We identified 2500 new cases of hyperuricemia during a mean follow-up of 5.0 years (223,552 person years). The participants in the highest quartiles of the PRAL and NEAP score had 21% (HR: 1.21, 95% CI: 1.07–1.35, p for trend <0.0001) and 17% (HR: 1.17, 95% CI: 1.04–1.31, p for trend <0.0001) higher risks for hyperuricemia, respectively, than those in the lowest quartiles, after adjusting for covariates. In this prospective cohort study, a higher dietary acid load was positively associated with a higher incidence of hyperuricemia in Korean adults. This suggests that an alkaline diet may be an effective strategy to reduce the future risk of elevated uric acid levels.

Serum Uric Acid Concentration in Patients with Cerebrovascular Disease (Ischemic Stroke and Vascular Dementia)

Introduction:

Significance of serum uric acid (UA) in cerebrovascular disease still remains controversial. UA is most abundant natural antioxidant in human plasma. Its antioxidant properties might protect against free radical damage, thereby reducing the risk of oxidative stress-related cognitive impairment and dementia.

Aim:

In our investigation, we determine the level of UA in 100 male patients diagnosed with the first ischemic brain stroke (blood samples were collected during the acute phase and post-acute phase), 100 male patients diagnosed with vascular dementia and 100 male healthy volunteers (control group).

Methods:

UA was determined using DIMENSION LxR automatic analyzer. Measurement of UA concentration was based on an enzymatic method (range 208-428 μmol/L).

Results:

The prevalence of hyperuricemia among ischemic stroke and vascular dementia patients was 30% and 8%, respectively. Serum UA concentration was higher 7 and 14 days after the stroke compared to the acute phase (24-48 hours after hospitalization) and these concentrations were significantly higher than those measured in the control group. UA levels measured at 24-48 hours after the first symptoms of ischemic stroke were strongly correlated with those measured after 7 days of treatment (r = 0.79, p = 0.001) or after 14 days (r = 0.839, p = 0.0049). No significant differences were found between ischemic stroke and vascular dementia groups.

Conclusion:

UA concentrations were higher in ischemic stroke and vascular dementia groups than in controls. UA increase may reflect vascular atherosclerosis and tissue hypoxia. UA monitoring in patients with cerebrovascular disease is essential, because UA is more harmful than protective.

Ethosomal Gel Formulation of Alpha Phellandrene for the Transdermal Delivery in Gout

Purpose: Purpose was to improve the skin compatibility and permeability of alpha phellandrene through an ethosomal gel formulation for the treatment of gout; as the oral use of the drug is reported to cause gastrointestinal disturbances and toxicities.

Methods: Alpha phellandrene loaded ethosomal formulation (APES) was prepared by cold method for the treatment of gout. APES were loaded into carbopol gel (APEG) by dispersion method. Physico-chemical characterizations of the APES were done by dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR) etc. In vitro release, permeation, haemo-compatibility and anti-inflammatory studies were conducted.

Results: APES showed a particle size of 364.83 ± 45.84 nm. The entrapment efficiency of the optimized formulation is found as 95.06 ± 2.51%. Hemolysis data indicated that APES does not cause any significant hemolysis. In vitro drug release studies were carried out using dialysis membrane technique and the amount of drug released from APES & APEG is found to be 95% and 94.21% respectively after 5 and6 hours. Kinetic data analysis revealed that APES & APEG follows first order and zero order release kinetics, respectively. The anti-inflammatory activity studies of the formulation are done by estimating its inhibitory effects on cyclooxygenase II (COX) II, lipoxygenase-5 (LOX-5), Myeloperoxidase (MPO), Inducible nitric oxide synthase (INOS) & cellular nitrite level using RAW 264.7 cells. The significant inhibition in the activities of the enzymes implies the anti-inflammatory activity of the formulations. Skin permeation study was carried out using porcine skin and revealed that the permeation of alpha phellandrene is increased from APES & APEG when compared with alpha-phellandrene solution (APS). Skin deposition study of APS, APES & APEG revealed better drug deposition from APEG (48.799 ± 1.547µg/cm² ) after 24 hours when compared with APS & APES.

Conclusion: Overall results indicate that the ethosomal formulation of alpha phellandrene through transdermal route is an effective alternative for oral use of the drug.

Total glucosides of paeony protects THP-1 macrophages against monosodium urate-induced inflammation via MALAT1/miR-876-5p/NLRP3 signaling cascade in gouty arthritis

BACKGROUND

Monosodium urate (MSU)-mediated inflammatory response is a crucial inducing factor in gouty arthritis. Here, we explored the underlying mechanism of total glucosides of paeony (TGP) in MSU-induced inflammation of THP-1 macrophages in gouty arthritis.

METHODS

3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect cell viability. Enzyme-linked immunosorbent assay (ELISA) was utilized to measure the production of interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α). Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot assay were conducted to determine RNA and protein expression. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull down assay were used to confirm the interaction between miR-876-5p and MALAT1 or NLR family pyrin domain containing 3 (NLRP3).

RESULTS

MSU-induced damage and inflammatory response in THP-1 macrophages were alleviated by the treatment of TGP in a dose-dependent manner. Overexpression of NLRP3 or MALAT1 reversed the protective effects of TGP in MSU-induced THP-1 macrophages. The binding relation between miR-876-5p and MALAT1 or NLRP3 was identified in THP-1 macrophages. MALAT1 up-regulated the expression of NLRP3 by sponging miR-876-5p in THP-1 macrophages. TGP suppressed MSU-induced inflammation in THP-1 macrophages through regulating MALAT1/miR-876-5p/NLRP3 axis. TGP suppressed MSU-induced activation of TLR4/MyD88/NF-κB pathway through regulating MALAT1/miR-876-5p/NLRP3 axis.

CONCLUSION

In conclusion, TGP suppressed MSU-induced inflammation in THP-1 macrophages through regulating MALAT1/miR-876-5p/NLRP3 axis and TLR4/MyD88/NF-κB pathway, suggesting that TGP was a promising active ingredient for gouty arthritis treatment.

Effects of dietary macronutrients on serum urate: results from the OmniHeart trial

BACKGROUND

Dietary recommendations to prevent gout emphasize a low-purine diet. Recent evidence suggests that the Dietary Approaches to Stop Hypertension (DASH) diet reduces serum urate while also improving blood pressure and lipids.

OBJECTIVE

To compare the effects of DASH-style diets emphasizing different macronutrient proportions on serum urate reduction.

METHODS

We conducted a secondary analysis of the Optimal Macronutrient Intake Trial to Prevent Heart Disease feeding study, a 3-period, crossover design, randomized trial of adults with prehypertension or hypertension. Participants were provided with 3 DASH-style diets in random order, each for 6 wk. Each DASH-style diet emphasized different macronutrient proportions: a carbohydrate-rich (CARB) diet, a protein-rich (PROT) diet, and an unsaturated fat-rich (UNSAT) diet. In the PROT diet, approximately half of the protein came from plant sources. We compared the effects of these diets on serum urate at weeks 4 and 6 of each feeding period.

RESULTS

Of the 163 individuals included in the final analysis, the mean serum urate at baseline was 5.1 mg/dL. Only the PROT diet reduced serum urate from baseline at the end of the 6-wk feeding period (-0.16 mg/dL; 95% CI: -0.28, -0.04; P = 0.007). Neither the CARB diet (-0.03 mg/dL; 95% CI: -0.14, 0.09; P = 0.66) nor the UNSAT diet (-0.01 mg/dL; 95% CI: -0.12, 0.09; P = 0.78) reduced serum urate from baseline. The PROT diet lowered serum urate by 0.12 mg/dL (95% CI: -0.20, -0.03; P = 0.006) compared with CARB and by 0.12 mg/dL (95% CI: -0.20, -0.05; P = 0.002) compared with UNSAT.

CONCLUSIONS

A DASH-style diet emphasizing plant-based protein lowered serum urate compared with those emphasizing carbohydrates or unsaturated fat. Future trials should test the ability of a DASH-style diet emphasizing plant-based protein to lower serum urate and prevent gout flares in patients with gout. This trial was registered at clinicaltrials.gov as NCT00051350.

Creation of an adequate animal model of hyperuricemia (acute and chronic hyperuricemia); study of its reversibility and its maintenance

AIM

Hyperuricemia is defined by the European Rheumatology Society as a uric acid level greater than 6 mg/dl (60 mg/l or 360 μmol/l). Our goal was to evaluate the hypouricemic effect of nettle. For this reason, we have first of all try to create an hyperuricemic animal model which is very suitable because at the level of literature there is not an exact model, there are many models and our objective is to set an adequate model.

MATERIALS AND METHODS

An attempt has been made to test acute and chronic hyperuricemia by varying the duration and method of induction of potassium oxonate. Similarly, attempts have been made to induce chronic hyperuricemia through an animal and vegetable diet. The reversibility of hyperuricemia was tested with a maintenance protocol.

KEY FINDINGS

For the creation of the hyperuricemia model, it has been shown that acute hyperuricemia cannot be induced by short administration of potassium oxonate and persistent chronic hyperuricemia can be induced only after daily administration of oxonate of potassium by intraperitoneal injection for 15 days. Indeed, hyperuricemia was reversible after stopping the administration of potassium oxonate. The high-purine diet is also capable of inducing chronic hyperuricemia but to a less extent.

SIGNIFICANCE

After creating an adequate model of hyperuricemia while setting the dose of potassium oxonate, route of administration and duration. A maintenance protocol was followed which subsequently made it possible to deduce that the daily administration of potassium oxonate must be continued to maintain the hyperuricemia.

Renal lipid accumulation, oxidative stress and uric acid handling in a rodent model of obesity and metabolic syndrome

Hyperuricemia is more prevalent among people with obesity and metabolic syndrome, and is associated with adverse clinical outcomes. We hypothesized that increased renal reabsorption of uric acid (UA) in obesity and metabolic syndrome may be an adaptive response of the kidney when faced with fatty acid-induced oxidative stress. To test this hypothesis, we examined lipid accumulation, markers of oxidative stress, and renal UA handling in Zucker diabetic fatty (ZDF) rats, and in matched lean control animals. Rats were randomized to either normal rodent chow or a diet supplemented with antioxidants (α-tocopheryl acetate, sodium selenite, zinc sulfate, and ascorbic acid), and were followed up for either 4 or 20 weeks after randomization. Dietary antioxidant supplementation had no significant effects in lean control rats but led to partial improvement in markers of elevated oxidative stress in the kidney of ZDF rats. Renal UA handling was not affected by antioxidant supplementation. We observed robust correlations between renal lipid content and oxidative stress markers in the pooled experimental groups, particularly in older animals after 20 weeks on the study diets. Dietary antioxidant supplementation did not prevent the gradual decline in renal function observed in older ZDF rats. These findings suggest that hyperuricemia in the ZDF rat model of obesity and the metabolic syndrome is not caused by renal oxidative stress, that there may be a pathophysiological link between lipid accumulation and oxidative stress in the kidney, and that antioxidant supplementation does not prevent age-related decline in renal function in ZDF rats.

Estimation of Primary Prevention of Gout in Men Through Modification of Obesity and Other Key Lifestyle Factors

IMPORTANCE

The population impact of modifying obesity and other key risk factors for hyperuricemia has been estimated in cross-sectional studies; however, the proportion of incident gout cases (a clinical end point) that could be prevented by modifying such factors has not been evaluated.

OBJECTIVE

To estimate the proportion of incident gout cases that could be avoided through simultaneous modification of obesity and other key risk factors.

DESIGN, SETTING, AND PARTICIPANTS

The Health Professionals Follow-up Study is a US prospective cohort study of 51 529 male health professionals enrolled in 1986 and followed up through questionnaires every 2 years through 2012. Self-reported gout cases were confirmed through June 2015. Clean and complete data used for this analysis were available in June 2016, with statistical analyses performed from July 2016 to July 2019.

EXPOSURES

From data collected in the validated questionnaires, men were categorized to low-risk groups according to combinations of the following 4 factors: normal body mass index (BMI [calculated as weight in kilograms divided by height in meters squared]; <25), no alcohol intake, adherence to Dietary Approaches to Stop Hypertension (DASH)-style diet (highest quintile of DASH diet score), and no diuretic use.

MAIN OUTCOMES AND MEASURES

Population attributable risks (PARs) for incident gout meeting the preliminary American College of Rheumatology survey criteria, overall and stratified by BMI.

RESULTS

We analyzed 44 654 men (mean [SD] age, 54.0 [9.8] years) with no history of gout at baseline. During 26 years of follow-up, 1741 (3.9%) developed incident gout. Among all participants, PAR for the 4 risk factors combined (BMI, diet, alcohol use, and diuretic use) was 77% (95% CI, 56%-88%). Among men with normal weight (BMI <25.0) and overweight (BMI 25.0-29.9), we estimated that more than half of incident gout cases (69% [95% CI, 42%-83%] and 59% [95% CI, 30%-75%], respectively) may have been prevented by the combination of DASH-style diet, no alcohol intake, and no diuretic use. However, among men with obesity (BMI ≥30), PAR was substantially lower and not significant (5% [95% CI, 0%-47%]).

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that addressing excess adiposity and other key modifiable factors has the potential to prevent the majority of incident gout cases among men. Men with obesity may not benefit from other modifications unless weight loss is addressed.

Effects of Low-Fat, Mediterranean, or Low-Carbohydrate Weight Loss Diets on Serum Urate and Cardiometabolic Risk Factors: A Secondary Analysis of the Dietary Intervention Randomized Controlled Trial (DIRECT)

OBJECTIVE

Weight loss diets may reduce serum urate (SU) by lowering insulin resistance while providing cardiometabolic benefits, something urate-lowering drugs have not shown in trials. We aimed to examine the effects of weight loss diets on SU and cardiometabolic risk factors.

RESEARCH DESIGN AND METHODS

This secondary study of the Dietary Intervention Randomized Controlled Trial (DIRECT) used stored samples from 235 participants with moderate obesity randomly assigned to low-fat, restricted-calorie (n = 85); Mediterranean, restricted-calorie (n = 76); or low-carbohydrate, non-restricted-calorie (n = 74) diets. We examined SU changes at 6 and 24 months overall and among those with hyperuricemia (SU ≥416 μmol/L), a relevant subgroup at risk for gout.

RESULTS

Among all participants, average SU decreases were 48 μmol/L at 6 months and 18 μmol/L at 24 months, with no differences between diets (P > 0.05). Body weight, HDL cholesterol (HDL-C), total cholesterol:HDL-C ratio, triglycerides, and insulin concentrations also improved in all three groups (P < 0.05 at 6 months). Adjusting for covariates, changes in weight and fasting plasma insulin concentrations remained associated with SU changes (P < 0.05). SU reductions among those with hyperuricemia were 113, 119, and 143 μmol/L at 6 months for low-fat, Mediterranean, and low-carbohydrate diets (all P for within-group comparison < 0.001; P > 0.05 for between-group comparisons) and 65, 77, and 83 μmol/L, respectively, at 24 months (all P for within-group comparison < 0.01; P > 0.05 for between-group comparisons).

CONCLUSIONS

Nonpurine-focused weight loss diets may simultaneously improve SU and cardiovascular risk factors likely mediated by reducing adiposity and insulin resistance. These dietary options could provide personalized pathways to suit patient comorbidity and preferences for adherence.

2,4-Diketo esters: Crucial intermediates for drug discovery

Convenient structures such as 2,4-diketo esters have been widely used as an effective pattern in medicinal chemistry and pharmacology for drug discovery. 2,4-Diketonate is a common scaffold that can be found in many biologically active and naturally occurring compounds. Also, many 2,4-diketo ester derivatives have been prepared due to their suitable synthesis. These synthetic drugs and natural products have shown numerous interesting biological properties with clinical potential as a cure for the broad specter of diseases. This review aims to highlight the important evidence of 2,4-diketo esters as a privileged scaffold in medicinal chemistry and pharmacology. Herein, numerous aspects of 2,4-diketo esters will be summarized, including synthesis and isolation of their derivatives, development of novel synthetic methodologies, the evaluation of their biological properties as well as the mechanisms of action of the diketo ester derivates. This paperwork is expected to be a comprehensive, trustworthy, and critical review of the 2,4-diketo ester intermediate to the chemistry community.

Association between retinol intake and hyperuricaemia in adults

OBJECTIVE

Current evidences on the association between hyperuricaemia and retinol intake remain inconsistent. Furthermore, no known studies have investigated the relationship between hyperuricaemia and retinol intake from animal food and plant food separately. This study aimed to assess the relationship between different sources of retinol intake and risk of hyperuricaemia among US adults.

DESIGN

Univariate and multivariate weighted logistic regression models and restricted cubic spline models were used to assess the associations of total, animal-derived and plant-derived retinol intakes with the risk of hyperuricaemia. Dietary retinol was measured through two 24-h dietary recall interviews. Hyperuricaemia was defined as serum uric acid level ≥7·0 and ≥6·0 mg/dl in men and women, respectively.

SETTING

Data from the National Health and Nutrition Examination Survey 2009-2014 were used in this cross-sectional study.

PARTICIPANTS

Overall, 12 869 participants aged ≥20 years were included.

RESULTS

Compared with the lowest quintile, the multivariable OR of hyperuricaemia for the highest quintile intake of total, animal-derived and plant-derived retinol were 0·71 (95 % CI 0·52, 0·96), 0·76 (95 % CI 0·59, 0·96) and 0·92 (95 % CI 0·72, 1·17), respectively. The inverse association between dietary intake of total retinol and the risk of hyperuricaemia was observed in men. Dose-response analyses revealed a novel linear trend between the risk of hyperuricaemia and total, animal-derived retinol intake separately.

CONCLUSIONS

Our findings indicated that intakes of total and animal-derived retinol were negatively associated with hyperuricaemia in US adults.

Formate metabolism in health and disease

BACKGROUND

Formate is a one-carbon molecule at the crossroad between cellular and whole body metabolism, between host and microbiome metabolism, and between nutrition and toxicology. This centrality confers formate with a key role in human physiology and disease that is currently unappreciated.

SCOPE OF REVIEW

Here we review the scientific literature on formate metabolism, highlighting cellular pathways, whole body metabolism, and interactions with the diet and the gut microbiome. We will discuss the relevance of formate metabolism in the context of embryonic development, cancer, obesity, immunometabolism, and neurodegeneration.

MAJOR CONCLUSIONS

We will conclude with an outlook of some open questions bringing formate metabolism into the spotlight.

Association of variability in uric acid and future clinical outcomes of patient with coronary artery disease undergoing percutaneous coronary intervention

BACKGROUND AND AIMS

Hyperuricemia is independently associated with cardiovascular disease (CVD) and is considered to be one of the major risk factors for CVD. However, the impact of inter-visit uric acid (UA) variability on cardiovascular risk remains undetermined.

METHODS

We enrolled 3202 patients with coronary artery disease (CAD), who received successful coronary intervention, in a cohort from Taipei Veterans General Hospital from 2006 to 2015. All post-baseline visits UA measurements using standard deviation (SD) were analyzed to correlate with long-term outcome. The primary outcome was the composite of cardiac death, nonfatal MI, nonfatal stroke (MACE). The secondary event was MACE and hospitalization for heart failure.

RESULTS

During an average 65.06 ± 32.1-month follow-up, there were 66 cardiovascular deaths, 175 nonfatal myocardial infarctions, 64 nonfatal strokes, 287 hospitalizations for heart failure, and 683 revascularization procedures. There was a linear association between high UA SD and future adverse events. Compared to the lowest quartile SD, subjects in the highest quartile SD had a higher risk of MACE (HR: 2.53, 95% CI: 1.78-3.59), myocardial infarction (HR: 2.43, 95% CI: 1.53-3.86), cardiovascular death (HR: 6.45, 95% CI: 2.52-16.55), heart failure-related hospitalization (HR: 3.43, 95% CI: 2.32-5.05), and total major CV events (HR: 2.72, 95% CI: 2.09-3.56). Furthermore, compared to the average achieved on-treatment UA value, increasing UA SD had a stronger association of higher risk of developing MACE (HR: 1.51, 95% CI: 1.36-1.68), myocardial infarction (HR: 1.37, 95% CI: 1.38-1.68), ischemic stroke (HR: 1.43, 95% CI: 1.13-1.82), CV death (HR: 1.77, 95% CI: 1.50-2.11), HF (HR: 1.43, 95% CI: 1.29-1.58), and total major CV events (HR: 1.46, 95% CI: 1.34-1.58).

CONCLUSIONS

High UA variability is associated with a higher risk of developing future cardiovascular events, suggesting the importance of maintaining stable serum UA levels and avoiding large fluctuations in CAD patients after percutaneous coronary intervention (PCI).

Correlation between Gout and Coronary Heart Disease in Taiwan: A Nationwide Population-Based Cohort Study

Background

Gout is the most common inflammatory arthritis in adult males. Patients with gout are at a higher risk of coronary heart disease (CHD). This study aimed to investigate the correlation between gout and CHD.

Methods

This was a retrospective cohort study that used data from the Longitudinal Health Insurance Database of Taiwan. The study subjects were 46,140 patients with new-onset gout during 2003-2010. To avoid selection bias, we used propensity score matching. A Cox proportional hazard model was used to analyze differences in the risk of CHD between patients with and without gout after controlling for related variables.

Results

The patients with gout had a higher risk of CHD than the patients without gout [adjusted hazards ratio (HR) = 1.34, 95% confidence interval (CI): 1.23-1.45]. The risk of CHD increased with older age. Other related factors for CHD included gender (female vs. male, adjusted HR = 0.86, 95% CI: 0.79-0.93), hypertension (adjusted HR = 1.53, 95% CI: 1.42-1.65), hyperlipidemia (adjusted HR = 1.18, 95% CI: 1.07-1.29), and diabetes mellitus (adjusted HR = 1.24, 95% CI: 1.13-1.36).

Conclusions

We found correlations between gout and CHD and other influencing factors including hypertension, hyperlipidemia, and diabetes mellitus. We also found that gender and age were associated with CHD.

Population Impact Attributable to Modifiable Risk Factors for Hyperuricemia

OBJECTIVE

To examine modifiable risk factors in relation to the presence of hyperuricemia and to estimate the proportion of hyperuricemia cases in the general population that could be prevented by risk factor modification, along with estimates of the variance explained.

METHODS

Using data obtained from 14,624 adults representative of the US civilian noninstitutionalized population, we calculated adjusted prevalence ratios for hyperuricemia, population attributable risks (PARs), and the variance explained according to the following 4 factors: body mass index (BMI; ≥25 kg/m² ), alcohol intake, nonadherence to a Dietary Approaches to Stop Hypertension (DASH) diet, and diuretic use.

RESULTS

BMI, alcohol intake, adherence to a DASH-style diet, and diuretic use were all associated with serum urate levels and the presence of hyperuricemia in a dose-dependent manner. The corresponding PARs of hyperuricemia cases for overweight/obesity (prevalence 60%), nonadherence to a DASH-style diet (prevalence 82%), alcohol use (prevalence 48%), and diuretic use (prevalence 8%) were 44% (95% confidence interval [95% CI] 41%, 48%), 9% (95% CI 3%, 16%), 8% (95% CI 5%, 11%), and 12% (95% CI 11%, 14%), respectively, whereas the corresponding variances explained were 8.9%, 0.1%, 0.5%, and 5.0%. Our simulation study showed the variance nearing 0% as exposure prevalence neared 100%.

CONCLUSION

In this nationally representative study, 4 modifiable risk factors (BMI, the DASH diet, alcohol use, and diuretic use) could be used to individually account for a notable proportion of hyperuricemia cases. However, the corresponding serum urate variance explained by these risk factors was very small and paradoxically masked their high prevalences, providing real-life empirical evidence for its limitations in assessing common risk factors.

Revisiting microtubule targeting agents: α-Tubulin and the pironetin binding site as unexplored targets for cancer therapeutics

Molecules that bind to tubulin and disrupt tubulin dynamics are known as microtubule targeting agents. Treatment with a microtubule targeting agent leads to cell cycle arrest followed by apoptosis. Tubulin inhibitors have been highly effective in the clinical treatment of a variety of tumors and are being investigated for treatment of several other diseases. Currently, all FDA approved microtubule inhibitors bind to β-tubulin. Given the overall success of tubulin-binding agents in anticancer chemotherapy, α-tubulin is an attractive and unexplored target. Herein, we will discuss pironetin, the only compound known to bind α-tubulin, with particular focus on the known biological properties, the total syntheses, exploration of its structure-activity relationship, and future directions.

Diagnostic challenges of spinal gout: A case series

INTRODUCTION

Spinal gout is rarely encountered in clinical practice, is easily misdiagnosed, and often remains undiagnosed. This paper aims to provide some clues that are the salient diagnostic features of spinal gout, particularly axial pain, radiculopathy, and myelopathy, as determined on the basis of our experience with a few cases as well as a literature review.

METHODS

We retrospectively reviewed the clinical data of 5 patients that were treated for axial pain and neurological symptoms associated with spinal gout between 2014 and 2017 in our hospital. Herein, we systematically describe the clinical characteristics of 5 patients with spinal gout. The 5 patients included 4 men and 1 woman, aged between 24 and 75 years. The most common clinical presentation included spinal pain, radiculopathy, and myelopathy. Four of the 5 patients had a history of gout and elevated serum uric acid levels.

RESULTS

Four patients underwent surgery, while the remaining patient underwent conservative treatment and biopsy due to poor general condition. Pathological examination of the surgical samples in the 4 surgical cases and the biopsy sample in the remaining case confirmed the presence of spinal gout tophi. The neurological symptoms of all 5 patients were relieved after treatment.

CONCLUSION

Due to its rarity and lack of typical defining criteria, the diagnosis of spinal gout is quite difficult. We recommend that patients presenting with axial pain; radicular pain or myelopathy; and especially high uric acid levels, with or without a history of gout, should be evaluated for spinal gout. Timely pathological examination of surgical or biopsy samples would help confirm the diagnosis and enable practitioners to provide the appropriate treatment to prevent disease progression.

Pharmacological basis for use of madecassoside in gouty arthritis: anti-inflammatory, anti-hyperuricemic, and NLRP3 inhibition

Objectives: Gouty arthritis is caused by the deposition of monosodium urate (MSU) crystals in joints, which is associated with the rise of serum urate content. This study aims to investigate the therapeutic effect of Madecassoside on gouty arthritis and hyperuricemia. Methods: DBA/1 mice were intradermally injected with MSU to stimulate joint inflammation or intraperitoneally injected with MSU to trigger peritonitis. Moreover, ICR mice were exposed to potassium oxonate to stimulate hyperuricemia. Results: Madecassoside repressed MSU-triggered pad swelling, joint 99mTc uptake, and joint inflammation in DBA/1 mice with gouty arthritis. Neutrophil infiltration and IL-1β & IL-6 & MCP-1 secretion was also alleviated in lavage fluids from DBA/1 mice with peritonitis due to Madecassoside treatment. Furthermore, Madecassoside decreased MSU-induced neutrophil cytosolic factor 1, caspase-1 and NLRP3 expression in mice with peritoneal inflammation. In hyperuricemic mice, Madecassoside improved renal dysfunction. Serum uric acid, BUN, and creatinine were down-regulated by Madecassoside. Conclusion: These findings indicate that Madecassoside has potential to ameliorate inflammation in both acute gouty arthritis model and peritonitis model, probably via regulating IL-1β and NLRP3 expression. Practical point: Madecassoside also exhibited a urate-lowering effect and a renal protective effect in hyperuricemic mice.

Beneficial Effect of Dietary Fiber on Hyperuricemia in Rats and Humans: A Review

Hyperuricemia is recognized as a lifestyle-related disease and the prevalence is increasing in many parts of the world. Excessive intake of purines increases serum uric acid concentration and is thought to be one factor causative of hyperuricemia. Therefore, it is thought that prevention of hyperuricemia by dietary control may be very important. This is an article of our basic research regarding the role of dietary fiber in the suppression of hyperuricemia induced by dietary purines in rats; in addition, clinical research suggesting the possibility that dietary fiber intake has a beneficial effect on the prevention or suppression of hyperuricemia in humans is discussed. Our own studies reveal that the test dietary fiber significantly suppresses the elevation of serum uric acid concentration induced by dietary RNA (12.3-46.2%), adenosine-5'-monophosphate (9.5-23.2%), adenosine (10.7-20.4%), or adenine (16.3-38.9%) and suppresses experimental hyperuricemia in rats. The mechanism is presumed to be mediated by suppression of the digestion and/or absorption of dietary purines by dietary fiber. In clinical studies, intake of dietary fiber decreases serum uric acid concentrations. Reports of recent epidemiological studies indicate that higher levels of hyperuricemia increase the prevalence of its comorbidities (e.g., chronic kidney disease, obesity, hypertension, diabetes, and cardiovascular disease) and dietary fiber intake is associated with significantly lower risk for hyperuricemia and its comorbidities. We wish to emphasize the importance of recognizing the validity of increased dietary fiber intake as a preventive or suppressive method for hyperuricemia and its comorbidities.

Hyperuricemia, urine uric excretion, and associated complications in thalassemia patients

Thalassemia patients have a high cell turnover rate due to chronic hemolysis and ineffective erythropoiesis; therefore, hyperuricemia is anticipated. This study aimed to identify the prevalence of hyperuricemia, gout and nephrolithiasis, conditions associated with serum uric acid (SUA), and urine uric acid excretion (UUA) in thalassemia patients. This was a cross-sectional study in patients aged 15 years or older at Chiang Mai University Hospital. All patients had blood and 24-h urine collection test. We enrolled 112 thalassemia patients in which 67.0% were female, 64.3% had beta thalassemia/Hb E, 76.8% were transfusion dependent, and 59.8% were post splenectomy. The median age was 29 (16-58) years. Mean SUA was 6.7 ± 2.0 mg/dl and hyperuricemia (SUA > 6.8 mg/dl) was found in 47 cases (45.2%). Intact spleen (ORs 4.3, 95%CI 1.55-12.50, p = 0.01) and lower FEuric (ORs 2.08, 95%CI 1.35-3.33, p < 0.01) were associated with hyperuricemia significantly. Seven (6.3%) had gouty arthritis and nine (8%) had microscopic hematuria, one case being confirmed nephrolithiasis. The mean UUA excretion was 981.3 ± 335.0 mg/day and UUA hyperexcretion (> 700 mg/24 h) was found in 83.3%. UUA hyperexcretion patients had renal hyperfiltration 46%, glomerular dysfunction 84%, and tubular dysfunction 7.7%. From our study, hyperuricemia was found in approximately 40% of thalassemia patients but gouty arthritis occurred only in few patients (6%). This may be explained by urinary uric hyperexcretion which is found in over 80%. The significant risk factors for hyperuricemia were intact spleen and lower fraction excretion of uric acid.

Phytochemical composition and the cholinesterase and xanthine oxidase inhibitory properties of seed extracts from the Washingtonia filifera palm fruit

The chemical composition and biological properties of palm Washingtonia filifera (Lindl.) H. Wendl. seeds are seldom studied.

Association of dietary fiber intake with hyperuricemia in U.S. adults

Current evidence on the relationship between dietary fiber intake and risk of hyperuricemia is limited.

Do etoricoxib and indometacin have similar effects and safety for gouty arthritis? A meta-analysis of randomized controlled trials

Background

Gout, a common medical condition that causes pain, can be treated by painkillers and anti-inflammatories. Indometacin and etoricoxib are two such drugs. However, no synthesized evidence exists comparing etoricoxib with indometacin in treating patients with gout.

Methods

We searched PubMed, Embase, Ovid MEDLINE, Web of Science, ScienceDirect, and the Cochrane Library without restrictions on language or publication date for potential randomized clinical trials comparing etoricoxib with indometacin for gout. The meta-analysis was conducted using a random-effects model.

Results

Search results yielded 313 references from six electronic databases, four of which met the eligibility criteria. These four were randomized clinical trials, and they involved a total of 609 patients with gouty arthritis. No significant differences were observed in pain score change, tenderness, or swelling between etoricoxib and indometacin; the mean differences were −0.05 (95% CI, −0.21 to 0.10), −0.06 (95% CI, −0.18 to 0.05), and −0.04 (95% CI, −0.17 to 0.09). However, the pooled data revealed that significantly fewer overall adverse events occurred in the etoricoxib group (n=105, 33.5%) than in the indometacin group (n=130, 44.1%) and the risk ratio was 0.77 (95% CI, 0.62–0.94).

Conclusion

Our meta-analysis revealed that etoricoxib and indometacin have similar effects on pain relief. However, etoricoxib has a significantly lower risk of adverse events than does indometacin, especially digestive system-related adverse events.

Urate crystal deposition, prevention and various diagnosis techniques of GOUT arthritis disease: a comprehensive review

Gout is described as difficult in joint sore, uttermost ordinarily in the principal metatarsophalangeal joint, attend from formation of urate monosodium crystallization in a joint space. Analysis might be affirmed by recognizable proof of urate monosodium precious stones in synovial liquid of the influenced joint. There has been expanded enthusiasm for gout in common scholarly and clinical practice settings. The pervasiveness of both hyperuricemia and gout has ascended as most recent decade of time in created nations and in this way weight of gout as expanded. The relationship of hyperuricemia and gout with cardio results for chance of added advantages in mediation on hyperuricemia was featured in this audit. Imaging procedures have ended up being helpful for location of urate statement, even before the primary clinical indications, empowering the assessment of the degree of testimony and giving target estimation of precious stone exhaustion amid urate-bringing down treatment. In advancement, the indication defines the pre diagnostic of gout and associated commodities is advised to prevent the inflammation, that image procedures will assess the weight on statement as well reaction to urinary bringing down clinical procedure in chose patients, lastly amongst last key goal on social insurance for clinical evaluation with gout is to totally project urate gem stores. In spite of the fact that the formal determination is defined with arthrocentesis and resulting examination, CT and ultrasound discoveries on addition of evaluation and execution of infection administration. The standard therapy methodology is available for the patients and whose disease is refractory to standard therapy.

Preparation of Sustained Release Tablet with Minimized Usage of Glyceryl Behenate Using Post-Heating Method

The purpose of this study was to prepare sustained release (SR) matrix tablets using a direct compression incorporated with a post-heating process. Allopurinol was selected due to the water-soluble property and Compritol 888 ATO® (also known as glyceryl behenate) was used as an SR matrix-forming agent. The API, SR material, microcrystalline cellulose, and magnesium stearate (lubricant) were mixed and prepared into a tablet by a direct compression method. The compressed tablets were stored in a dry oven at four temperatures (60, 70, 80, and 90°C) and for three time periods (15, 30, 45 min). The DSC and PXRD data indicated that the crystallinity of the API was not altered by the post-heating method. However, SEM images demonstrated that Compritol 888 ATO® was melted by the post-heating method, and that the melted Compritol 888 ATO® could form a strong matrix. This strong matrix led to the significant sustained release behavior of hydrophilic APIs. As little as 3 mg of Compritol 888 ATO® (0.65% of total tablet weight), when heated at 80°C for 15 min, showed sustained release over 10 h. The post-heating method exerted a significant influence on lipid-based matrix tablets and allowed a reduction in the amount of material required for a water-soluble drug. This will also provide a valuable insight into lipid-based SR tablets and will allow their application to higher quality products and easier processing procedures.

The Effect of Lesinurad in Combination With Allopurinol on Serum Uric Acid Levels in Patients With Gout

The objective of the study was to evaluate the effect of lesinurad, a selective uric acid uptake inhibitor, alone and in combination with the xanthine oxidase inhibitor allopurinol, on serum uric acid and urinary urate excretion in patients with gout and hyperuricemia. A phase 1b, multicenter, open‐label, multiple‐dose study was carried out in patients with gout with serum uric acid ≥8 mg/dL following washout of urate‐lowering therapy. Patients were treated with allopurinol 300 mg/day alone in week 1; lesinurad 400 or 600 mg/day was added in week 2, followed by lesinurad 400 or 600 mg/day alone in week 3. Serum uric acid and urine uric acid were evaluated each week. Safety was assessed throughout the study. Lesinurad 400 or 600 mg/day added to allopurinol 300 mg/day reduced serum uric acid by 60% and 72%, respectively, versus allopurinol alone (37%) or lesinurad 400 mg/day (44%) or 600 mg/day (47%) alone. A 100% response rate of serum uric acid <6 mg/dL was achieved by all combinations (serum uric acid <5 mg/dL by 50%‐90%). Mean 24‐hour urate excretion compared with baseline was –35% with allopurinol, +36% and +56.5% with lesinurad 400 mg/day and 600 mg/day, respectively, and –11.6% and –7.1% with the respective combination therapies. Treatments were well tolerated. In this phase 1 trial, lesinurad added to allopurinol resulted in greater serum uric acid reduction than did allopurinol or lesinurad monotherapy.

In vitro and in silico interaction of faba bean (Vicia faba L.) seed extract with xanthine oxidase and evaluation of antioxidant activity as a therapeutic potential

Acetone extract of faba bean (Vicia faba L.) was found to be highest total phenol and flavonoid content among all extracts. Antioxidant activity for inhibition percentage (free radical scavenging activity) had 86.47% for acetone extract, and 97.36% for ascorbic acid respectively. IC₅₀ value of ascorbic acid and acetone extact were found to be 9 μg/mL ± 0.20 and 30 μg/mL ± 0.21. Faba bean seeds had catechin, epicatechin, gallic acid and ellagic acid which on molecular docking study revealed that it binds effectively with xanthine oxidase by binding energy of -7.78, -6.11, -6.39, -5.78 kcal/mol respectively compared to allopurinol drug having binding energy of -4.94 kcal/mol. Gallic acid, ellagic acid, catechin, epicatechin (polyphenols) and allopurinol bind other than catalytic residues (Glu-1261) of xanthine oxidase. In vitro and in silico analysis recommended that mode of enzyme inhibition was mixed type.

Pharmacologic targeting ERK1/2 attenuates the development and progression of hyperuricemic nephropathy in rats

The pathogenesis of hyperuricemia-induced chronic kidney disease is largely unknown. In this study, we investigated whether extracellular signal–regulated kinases1/2 (ERK1/2) would contribute to the development of hyperuricemic nephropathy (HN). In a rat model of HN induced by feeding mixture of adenine and potassium oxonate, increased ERK1/2 phosphorylation and severe glomerular sclerosis and renal interstitial fibrosis were evident, in parallel with diminished levels of renal function and increased urine microalbumin excretion. Administration of U0126, which is a selective inhibitor of the ERK1/2 pathway, improved renal function, decreased urine microalbumin and inhibited activation of renal interstitial fibroblasts as well as accumulation of extracellular proteins. U0126 also inhibited hyperuricemia-induced expression of multiple profibrogenic cytokines/chemokines and infiltration of macrophages in the kidney. Furthermore, U0126 treatment suppressed xanthine oxidase, which mediates uric acid production. It also reduced expression of the urate anion exchanger 1, which promotes reabsorption of uric acid, and preserved expression of organic anion transporters 1 and 3, which accelerate uric acid excretion in the kidney of hyperuricemic rats. Finally, U0126 inhibited phosphorylation of Smad3, a key mediator in transforming growth factor (TGF-β) signaling. In cultured renal interstitial fibroblasts, inhibition of ERK1/2 activation by siRNA suppressed uric acid-induced activation of renal interstitial fibroblasts. Collectively, pharmacologic targeting of ERK1/2 can alleviate HN by suppressing TGF-β signaling, reducing inflammation responses, and inhibiting the molecular processes associated with elevation of blood uric acid levels in the body. Thus, ERK1/2 inhibition may be a potential approach for the prevention and treatment of hyperuricemic nephropathy.

Genetic variants in two pathways influence serum urate levels and gout risk: a systematic pathway analysis

The aims of this study were to identify candidate pathways associated with serum urate and to explore the genetic effect of those pathways on the risk of gout. Pathway analysis of the loci identified in genome-wide association studies (GWASs) showed that the ion transmembrane transporter activity pathway (GO: 0015075) and the secondary active transmembrane transporter activity pathway (GO: 0015291) were both associated with serum urate concentrations, with P_FDR values of 0.004 and 0.007, respectively. In a Chinese population of 4,332 individuals, the two pathways were also found to be associated with serum urate (P_FDR = 1.88E-05 and 3.44E-04, separately). In addition, these two pathways were further associated with the pathogenesis of gout (P_FDR = 1.08E-08 and 2.66E-03, respectively) in the Chinese population and a novel gout-associated gene, SLC17A2, was identified (OR = 0.83, P_FDR = 0.017). The mRNA expression of candidate genes also showed significant differences among different groups at pathway level. The present study identified two transmembrane transporter activity pathways (GO: 0015075 and GO: 0015291) were associations with serum urate concentrations and the risk of gout. SLC17A2 was identified as a novel gene that influenced the risk of gout.