Latest evidence on gout management: what the clinician needs to know

The patient with a painful knee

Knee pain encompasses a wide array of differential diagnoses and can often pose a diagnostic challenge, as it can have traumatic or non-traumatic causes. A good clinical history, assessment and anatomical knowledge gives a strong foundation to narrow down the diagnosis, and understanding the correct imaging modality and findings further informs correct and timely management. This article reviews various disease processes including fractures, inflammatory, infective and neoplastic causes, and discusses the assessment and various imaging modalities to aid diagnosis in both primary and secondary care.

Separable and Inseparable Silk Fibroin Microneedles for the Transdermal Delivery of Colchicine: Development, Characterization, and Comparisons

Colchicine is the first-line option for both the treatment and prophylaxis of gout flares. However, due to potentially severe side effects, the clinical use of colchicine is limited. A well-tolerated and safe delivery system for colchicine is widely desired. For this purpose, colchicine-loaded inseparable microneedles were fabricated using silk fibroin. Additionally, separable microneedles made of silk fibroin as the needle tips and PVP K30 as the base material were developed. Both types of microneedles were evaluated for their mechanical strength, swelling and dissolution characteristics, insertion abilities, degradation properties, in vitro penetration, skin irritation, and in vivo anti-gout effects. The results demonstrated that separable microneedles had greater mechanical strength and insertion ability. Moreover, the separable microneedles separated quickly and caused little skin irritation. In the pharmacodynamic test, mice with acute gouty arthritis responded significantly to treatment with separable microneedles. In conclusion, the separable silk fibroin-based microneedles provide a promising route for colchicine delivery.

Design of 3-Phenylcoumarins and 3-Thienylcoumarins as Potent Xanthine Oxidase Inhibitors: Synthesis, Biological Evaluation, and Docking Studies

Coumarin scaffold has proven to be promising in the development of bioactive agents, such as xanthine oxidase (XO) inhibitors. Novel hydroxylated 3-arylcoumarins were designed, synthesized, and evaluated for their XO inhibition and antioxidant properties. 3-(3'-Bromophenyl)-5,7-dihydroxycoumarin (compound 11) proved to be the most potent XO inhibitor, with an IC50 of 91 nM, being 162 times better than allopurinol, one of the reference controls. Kinetic analysis of compound 11 and compound 5 [3-(4'-bromothien-2'-yl)-5,7-dihydroxycoumarin], the second-best compound within the series (IC50 of 280 nM), has been performed, and both compounds showed a mixed-type inhibition. Both compounds present good antioxidant activity (ability to scavenge ABTS radical) and are able to reduce reactive oxygen species (ROS) levels in H2 O2 -treated cells. In addition, they proved to be non-cytotoxic in a Caco-2 cells viability assay. Molecular docking studies have been carried out to correlate the compounds' theoretical and experimental binding affinity to the XO binding pocket.

Autonomous capillary electrophoresis processing and analysis of dried blood spots for high-throughput determination of uric acid

A new set-up for fully autonomous and high-throughput capillary electrophoresis (CE) analyses of dried blood spot (DBS) samples is presented. The DBS samples were prepared by collecting exactly 5 μL of capillary blood from a finger-prick onto a pre-punched DBS disc in a disposable plastic CE vial and by in-vial blood drying. The vials with the DBS samples were then loaded into a commercial CE instrument for a fully unmanned sample processing and analysis. A fused-silica capillary of the CE instrument was first used for the transfer of 100 μL of elution solvent to each vial, in-vial DBS elution, and in-vial eluate homogenization. The same capillary was also used for at-line injection, separation, and selective analysis of the resulting eluates. Novel CE sequences were tailor-programmed for consecutive processing and analyses of multiple DBSs, which facilitated a fully autonomous determination of uric acid with a throughput of 240 DBS samples per day (24 h). The presented analytical protocol (using 100 μm i. d./30 cm capillary; 30 mM 2-(N-morpholino)-ethanesulfonic acid, 30 mM l-histidine, and 30 μM cetyltrimethylammonium bromide background electrolyte solution; and UV detection at 292 nm) provided excellent precision at endogenous and spiked uric acid concentrations with RSD values of peak areas below 3.2%. Calibration curves were linear over the 33.3 - 1200 μM range (R² better than 0.998), limits of detection and quantification in the original capillary blood were 10 and 33.3 μM, respectively, and were well below the uric acid clinical range (140-420 μM). The stability of uric acid in DBS samples stored at laboratory temperature for up to 2 months was also excellent demonstrating less than a 4.2% decrease in uric acid concentrations. The actual set-up might thus be highly attractive for clinical subjects and laboratories because it is minimally invasive and requires minimum intervention from laboratory staff.

Towards the Development of Dual Hypouricemic and Anti-inflammatory Candidates: Design, Synthesis, Stability Studies and Biological Evaluation of Some Mutual Ester Prodrugs of Febuxostat-NSAIDs

Treatment of gout involves two basic approaches: reducing the serum uric acid mainly by xanthine oxidase inhibitors (XOIs) and alleviating the intensity of the accompanying acute arthritic inflammation using non-steroidal anti-inflammatory drugs (NSAIDs). Febuxostat (FEB) is the first non-purine XOI approved for the treatment of hyperuricemia and gout. The present study aims at combining the hypouricemic effect of FEB and the anti-inflammatory (AI) properties of NSAIDs in a single entity by adopting the "mutual prodrug" approach. Accordingly, a series of seven ester prodrugs comprising basically FEB together with different NSAIDs namely, diclofenac (4), ibuprofen (5), ketoprofen (6), indomethacin (7), naproxen (8), ketorolac (9) and etodolac (10) was synthesized. All the investigated seven prodrugs (4-10) were equipotent or even superior to their corresponding parent drugs in the hypouricemic and AI activities, together with a gastrointestinal (GI) safety profile. Among this series, the prodrug FEB-DIC (4) showed excellent dual in vivo hypouricemic and anti-inflammatory activity (43.60 % and 15.96 %, respectively) when compared to the parent drugs FEB and diclofenac (36.82 % and 12.10 %, respectively) and its physical mixture (37.28 % and 12.41 %, respectively). Investigation of the in vitro chemical stability and hydrolysis of the prodrug (4) in aqueous and biological samples using a developed HPLC method confirmed its stability in various pHs, whereas rapid hydrolysis to the parent drugs in liver homogenate and human plasma was proven. Finally, it is concluded that the mutual prodrug approach could be successfully used in drug design and development for overcoming undesirable difficulties without losing the desired activities of the parent drugs.

Kidney Drug Transporters in Pharmacotherapy

The kidney functions not only as a metabolite elimination organ but also plays an important role in pharmacotherapy. The kidney tubule epithelia cells express membrane carriers and transporters, which play an important role in drug elimination, and can determine drug nephrotoxicity and drug-drug interactions, as well as constituting direct drug targets. The above aspects of kidney transport proteins are discussed in the review.

Novel xanthine oxidase inhibitory peptides derived from whey protein: identification, in vitro inhibition mechanism and in vivo activity validation

As the development of hyperuricemia (HUA) and gout continues to accelerate worldwide, there is increasing interest in the use of xanthine oxidase (XO) inhibitors as therapeutic agents for the management of HUA and gout. In the present study, XO inhibitory peptides were identified from whey protein isolate (WPI) hydrolysates, and the underlying inhibitory mechanism and in vivo activities was investigated. WPI hydrolysates were isolated and purified, and two peptides (ALPM and LWM) with lower binding energy were screened by molecular docking. The result showed that these two peptides interacted with residues around the active site of XO through hydrogen bond and hydrophobic interaction. The IC₅₀ values of ALPM and LWM were 7.23 ± 0.22 and 5.01 ± 0.31 mM, respectively. According to the Lineweaver-Burk curve, the inhibition types of ALPM and LWM were non-competitive inhibition. Circular dichroism (CD) spectra indicated ALPM and LWM could change the secondary structure of XO. Molecular dynamics simulations revealed that XO-peptide complexes were more stable and compact than XO. Moreover, animal studies have shown that ALPM and LWM have anti-hyperuricemia effects in vivo. This study suggested that ALPM and LWM can be considered as natural XO inhibitors for the treatment of HUA.

Portable, Disposable, Biomimetic Electrochemical Sensors for Analyte Detection in a Single Drop of Whole Blood

Current diagnostics call for rapid, sensitive, and selective screening of physiologically important biomarkers. Point-of-care (POC) devices for the rapid, reliable, and easy acquisition of bioinformation at, or near the patient, offer opportunities for better healthcare management. Electrochemical biosensors with high sensitivity and ease of miniaturization are advantageous for such applications. We report a photolithographically micropatterned PEDOT:PSS and silk protein-based fully organic 3-electrode sensor (O3ES) for ultralow volume (single drop—10 µL) detection of analytes in whole blood. The O3ES produces reliable electrochemical signals in whole blood from a mouse model with minimal biofouling interference. The O3ES is demonstrated as a portable device for the simultaneous detection of dopamine, ascorbic acid and uric acid using voltammetry techniques. The O3ES displays excellent sensitivity towards each analyte in whole blood, and in the presence of each other. The water-based, ambient processing of the sensors allows the immobilization of enzymes in the organic working electrode. Amperometric detection of uric acid via uricase with high sensitivity in whole blood is demonstrated. Finally, the performance of the O3ES under enzymatic degradation is studied by monitoring sensitivity over an operating lifetime of ~14 days. This work demonstrates the realization of low-cost, disposable POC sensors capable of detecting blood metabolites using ultralow sample volumes.

Effects of secukinumab and adalimumab on serum uric acid level in patients with plaque psoriasis

BACKGROUND

Psoriasis is a chronic systemic inflammatory disease, and hyperuricemia is a common comorbidity in patients with psoriasis. However, there are limited reports on the relationship between serum uric acid levels and biological treatment efficacy. The purposes of this study were to compare the differences in serum uric acid levels between patients with psoriasis and healthy controls and analyze the risk of hyperuricemia.

METHODS

A total of 196 patients with psoriasis and 191 age- and sex-matched healthy controls were enrolled in this retrospective cohort study. One hundred and twenty-seven patients with severe psoriasis were treated with biologics. Sixty-eight patients received adalimumab, and 59 patients received secukinumab. Serum uric acid levels were measured at baseline, week 24, and week 48 of treatment.

RESULTS

Patients with psoriasis had higher serum uric acid levels than healthy controls (6.4 ± 1.7 mg/dL vs. 5.7 ± 1.5 mg/dL, P  < 0.001). Hyperuricemia was found in 33.7% (66/196) of patients with psoriasis, which was significantly higher than that in healthy controls (13.1% [25/191], P  < 0.001). Serum uric acid levels and hyperuricemia were not related to the severity of psoriasis ( P  > 0.05). No significant changes in serum uric acid levels and hyperuricemia were observed following adalimumab treatment ( P  > 0.05). The serum uric acid level in patients treated with secukinumab was 6.7 ± 1.6 mg/dL at week 24, which was not statistically different from that at baseline (6.6 ± 1.4 mg/dL, P  = 0.885). Serum uric acid levels were significantly decreased at week 48 (6.3 ± 1.5 mg/dL vs. 6.6 ± 1.4 mg/dL, P  = 0.007) in patients treated with secukinumab. Secukinumab had no significant effect on hyperuricemia either ( P  > 0.05).

CONCLUSIONS

The serum uric acid levels and prevalence of hyperuricemia in patients with psoriasis were significantly higher than those in healthy controls. Secukinumab treatment for 48 weeks successfully decreased serum uric acid levels in patients with psoriasis, whereas adalimumab had no significant effect on serum uric acid levels.

Anti-Hyperuricemic Effect of Ethyl Acetate Sub-Fractions from Chrysanthemum morifolium Ramat. Dried Flowers on Potassium Oxonate-Induced Hyperuricemic Rats

Xanthine oxidase (XO) plays an important role in purine degradation in humans. The study aimed to determine the XO inhibitory potential of Chrysanthemum morifolium dried flower ethyl acetate sub-fractions and its anti-hyperuricemic effect in rat models. Bioassay-guided fractionation based on XO inhibitory assay was employed to obtain bioactive fractions and sub-fractions. In vitro cytotoxicity and cellular antioxidant capacity of the sub-fraction and its mode of XO inhibition were also investigated. The anti-hyperuricemic effect of the bioactive sub-fraction was investigated using rat models via oral consumption, and followed by an XO mRNA gene expression study. The compounds in the bioactive sub-fractions were identified putatively using HPLC-Q-TOF-MS/MS. Ethyl acetate (EtOAc) fraction exhibited the highest XO inhibition among the fractions. It was further fractionated into 15 sub-fractions. F10 exhibited high XO inhibitory activity, cellular pro-proliferative effect, and intracellular antioxidant activity among the sub-fractions tested. This sub-fraction was non-cytotoxic at 0.1–10 µg/mL, and very effective in lowering serum and urine uric acid level in rat models upon oral consumption. A total of 26 known compounds were identified and seven unknown compounds were detected via HPLC-Q-TOF–MS/MS analysis. The possible mechanisms contributing to the anti-hyperuricemic effect were suggested to be the non-competitive inhibition of XO enzyme, XO gene expression down-regulation, and the enhancement of uric acid excretion.

Febuxostat-based amides and some derived heterocycles targeting xanthine oxidase and COX inhibition. Synthesis, in vitro and in vivo biological evaluation, molecular modeling and in silico ADMET studies

Various febuxostat derivatives comprising carboxamide functionalities and different substituted heterocycles were synthesized and evaluated for their biological activities as xanthine oxidase (XO) and cyclooxygenase (COX) inhibitors. All the tested compounds exhibited variable in vitro XO inhibitory activities (IC₅₀ values 0.009-0.077 µM), among which the analog 17 has emerged as the most potent derivative (IC₅₀ 0.009 µM), representing nearly 3-times the potency of febuxostat (IC₅₀ 0.026 µM). The same analogs were further investigated for their in vitro COX-1 and COX-2 inhibitory activity, where fifteen analogs demonstrated recognizable COX-2 inhibitory potential (IC₅₀ values range 0.04 - 0.1 µM), when correlated with celecoxib (IC₅₀ 0.05 µM), together with appreciable selectivity indices. Compounds 5a, 14b, 17, 19c, 19e and 21b that showed significant in vitro XO and/ or COX inhibitory potentials were further investigated for their in vivo hypouricemic as well as anti-inflammatory activities. Interestingly, the in vivo results were concordant with the collected in vitro data. Docking of compounds 5a, 14b, 17, 19c, 19e and 21b with the active sites of XO and COX-2 isozymes demonstrated superior binding profile compared with the reported ligands (febuxostat and celecoxib, respectively). Their docking scores were reasonable and cohering to a great extent with their corresponding in vitro IC₅₀ values. Moreover, in silico computation of the predicted pharmacokinetic and toxicity properties (ADMET), together with the ligand efficiency (LE) of the same six compounds suggesting their liability to act as new orally active drug candidates with a predicted high safety profile.

Xanthine Oxidase and Transforming Growth Factor Beta-activated Kinase 1: Potential Targets for Gout Intervention

BACKGROUND

Gout, inflammatory arthritis caused by the deposition of monosodium urate crystals into affected joints and other tissues, has become one of the major health problems of today's world. The main risk factor for gout is hyperuricemia, which may be caused by excessive or insufficient excretion of uric acid. The incidence is usually in the age group of 30- 50 years, commonly in males. In developed countries, the incidence of gout ranges from 1 to 4%. Despite effective treatments, there has been an increase in the number of cases over the past few decades.

OBJECTIVE

In recent years, the development of targeted drugs in gout has made significant achievements. The global impact of gout continues to increase, and as a result, the focus of disease-modifying therapies remains elusive. In addition, the characterization of available instrumental compounds is urgently needed to explore the use of novel selective and key protein-ligand interactions for the effective treatment of gout. Xanthine oxidase (XO) is a key target in gout to consider the use of XO inhibitors in patients with mild to moderate condition, however, the costs are high, and no other direct progress has been made. Despite many XO inhibitors, a selective potent inhibitor for XO is limited. Likewise, in recent years, attention has been focused on different strategies for the discovery and development of new selectivity ligands against transforming growth factor beta- activated kinase 1 (TAK1), a potential therapeutic target for gout. Therefore, the insight on human XO structure and TAK1 provides a clue into protein-ligand interactions and provides the basis for molecular modeling and structure-based drug design.

CONCLUSION

In this review, we briefly introduce the clinical characteristics, the development of crystal, inhibitors, and crystal structure of XO and TAK1 protein.

Pharmacologic Management of Gout in Patients with Cardiovascular Disease and Heart Failure

Gout is the most common inflammatory arthritis and is often comorbid with cardiovascular disease (CVD). Hyperuricemia and gout are also independent risk factors for cardiovascular events, worsening heart failure (HF), and death. The recommended treatment modalities for gout have important implications for patients with CVD because of varying degrees of cardiovascular and HF benefit and risk. Therefore, it is critical to both manage hyperuricemia with urate-lowering therapy (ULT) and treat acute gout flares while minimizing the risk of adverse cardiovascular events. In this review, the evidence for the safety of pharmacologic treatment of acute and chronic gout in patients with CVD and/or HF is reviewed. In patients with CVD or HF who present with an acute gout flare, colchicine is considered safe and potentially reduces the risk of myocardial infarction. If patients cannot tolerate colchicine, short durations of low-dose glucocorticoids are efficacious and may be safe. Nonsteroidal anti-inflammatory drugs should be avoided in patients with CVD or HF. The use of canakinumab and anakinra for acute gout flares is limited by the high cost, risk of serious infection, and relatively modest clinical benefit. For long-term ULT, allopurinol, and alternatively probenecid, should be considered first-line treatments in patients with CVD or HF given their safety and potential for reducing cardiovascular outcomes. An increased risk of cardiovascular death and HF hospitalization limit the use of febuxostat and pegloticase as ULT in this population. Ultimately, the selection of agents used for acute gout management and long-term ULT should be individualized according to patient and agent cardiovascular risk factors.

Serum uric acid and left ventricular hypertrophy in hypertensive patients in Ado-Ekiti

Introduction

systemic hypertension is a foremost risk factor for cardiovascular morbidity and mortality. Its actions are manifested on organs like the brain, heart and kidneys. High serum uric acid (SUA) escalates cardiovascular vulnerability in patients with systemic hypertension.

Methods

a cross-sectional study was performed in 271 (178 females, 93 males) patients with systemic hypertension. Two hundred and seventy one healthy age and sex matched non-hypertensive persons obliged as controls. Left ventricular hypertrophy (LVH) was estimated by echocardiography. Blood samples were collected for measuring uric acid levels.

Results

mean SUA was significantly higher among the hypertensive patients (371±125μmol/L) than in the controls (269 ± 101.4μmol/L; p < 0.001), and the prevalence of hyperuricemia was 46.9% among the hypertensives and 11.1% among the controls (P < 0.001). Independent predictors of SUA were class of systemic hypertension, left ventricular mass index (LVMI), body mass index (BMI) and age. However, class of hypertension was the best independent predictor of SUA levels in the multivariate regression model (β = 0.597). Linear regression revealed SUA levels ≥ 430μmols/l as a predictor of stage 2 hypertension (F = 26.620, p = < 0.001). Among the hypertensive patients, LVH was present in 39.3% of those with hyperuricemia and in 28.0% of those with normal SUA levels (p = 0.003).

Conclusion

results indicate serum uric acid is positively correlated with hypertension and a reliable indicator of LVH in study population.

Management of ulcerated finger pad tophi

Finger pad tophi are an unusual but not very rare presentation of uncontrolled gout. Unlike tophaceous lesions of other locations, finger pad tophi are often difficult to diagnose at presentation due to resemblance to a variety of nodular lesions, coexistence with other connective tissue disorders and sometimes occurrence in asymptomatic hyperuricemia. They also pose a therapeutic dilemma due to a lack of clear treatment guidelines. Several case reports of finger pad tophi have been published before, focusing mainly on diagnosis and medical management. We discuss here a case of thumb pad tophi as primary presentation of undiagnosed asymptomatic hyperuricemia and treated surgically with excision and full-thickness skin graft along with urate-lowering therapy.

This article highlights the diagnosis and treatment of finger pad tophi. We also discuss the surgical management of tophaceous lesions of hands and digits.

Comparative Study of Real-Life Management Strategies in Gout: Data From Two Protocolized Gout Clinics

OBJECTIVE

To compare outcomes of 2 gout clinics that implemented different treatment strategies.

METHODS

Patients newly diagnosed with gout and a follow-up of 9-15 months were included. Co-primary outcomes were the proportion of patients reaching a serum uric acid (UA) ≤0.36 mmoles/liter and free of flares. Secondary outcomes were the proportion of patients requiring treatment intensification and experiencing adverse events. One clinic adopted a strict serum UA (≤0.30 mmoles/liter target) strategy, with early addition of a uricosuric to allopurinol, and the other clinic adopted a patient-centered (PC) strategy emphasizing a shared decision based on serum UA and patient satisfaction with gout control. Independent t-tests or chi-square tests were used to test differences in outcomes, and logistic regressions were used to adjust the effect of the treatment center on outcomes for confounders.

RESULTS

In total, 126 and 86 patients had a follow-up mean ± SD of 11.3 ± 1.8 versus 11.1 ± 1.9 months. In the UA strategy, 105 of 126 patients (83%) compared to 63 of 86 (74%) in the PC strategy (P = 0.10) reached the threshold of ≤0.36 mmoles/liter; and 58 of 126 (46%) versus 31 of 86 (36%) were free of flares (P = 0.15). In the UA strategy, 76 of 126 patients (60%) were on allopurinol monotherapy compared to 63 of 86 (73%) in the PC strategy (P = 0.05), yet the number of adverse events was not different (n = 25 [20%] versus n = 20 [23%]; P = 0.55). Adjusting for confounders did not substantially change these associations.

CONCLUSION

A strict UA strategy resulted in a nonsignificantly higher proportion of patients reaching a serum UA ≤0.36 mmoles/liter and being free of flares. This result was accomplished with significantly more therapy intensification. The small sample size plays a role in the significance of results.

Anti-hyperuricemic and Anti-inflammatory Effects of Marantodes pumilum as Potential Treatment for Gout

Marantodes pumilum (Primulaceae) has been used in Malaysian folk medicine to help women regain strength after delivery and for “sickness in the bones.” It was previously revealed that its extracts inhibited xanthine oxidase (XO) activity in vitro. The leaves and roots of M. pumilum var. alata (MPA), var. pumila (MPP), and var. lanceolata (MPL) were individually extracted in ethanol (80%). The anti-hyperuricemic activity was initially assessed by XO inhibition with a spectrophotometric in vitro assay. The most active extract was further investigated on hyperuricemic rat model induced by potassium oxonate to determine serum uric acid levels and liver XO effect. The in vitro anti-inflammatory activity was carried out on monosodium urate (MSU) crystal-induced pro-inflammatory cytokines (i.e., interleukin (IL)1α, IL-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α) secretion using human peripheral blood mononuclear cells and ELISA technique, and prostaglandin E₂ (PGE₂)secretion using radioimmunoassay. The active extract was then investigated on gout-induced inflammation with MSU crystals to determine pro-inflammatory cytokines and PGE₂ secretion levels in the synovial fluid of rat knee joint. Quantitative analysis using validated HPLC was performed on the extracts to determine presence of bioactive flavonoids. The findings revealed that extract of MPP leaves gave the highest inhibitory activity on XO (IC₅₀ 130.5 μg/mL) compared to other extracts tested. However, all extracts possessed significantly lower activity compared to allopurinol (IC₅₀ 0.13 μg/mL). Oral administration of MPP leaf extract (200 mg/kg) significantly reduced serum uric acid level in hyperuricemic rats in time-dependent manner to the baseline level and it was as effective as allopurinol (5 mg/kg). The extract also inhibited liver XO activity (25%) compared to allopurinol (45%). In vitro anti-inflammatory assay showed that extract of MPP roots inhibited MSU crystals-induced secretion of IL-1α, IL-1β, IL-8, TNF-α, and PGE₂ with IC₅₀ values of 36, 25, 38, 18, and 46 μg/mL, respectively. Oral administration of the MPP root extract (200 mg/kg) significantly decreased IL-1α, IL-1β, IL-6, TNF-α, and PGE₂ levels in rat’s synovial fluid as effective as indomethacin. There were no significant body weight changes of all experimental animals. MPP extracts showed presence of myricetin, quercetin and kaempferol. Myricetin was detected with values of 0.2 and 0.6 mg/g for root and leaf extracts, respectively. The anti-hyperuricemic of MPP leaf and anti-inflammatory of MPP root indicated that MPP may be promising for complementary therapy of gout.

Understanding the patient voice in gout: a quantitative study conducted in Europe

Background

Although commonly diagnosed, gout often remains a poorly managed disease. This is partially due to a lack of awareness of the long-term effect of gout among patients and healthcare professionals.

Aim

To understand unmet needs for patients and provide insight into achieving better treatment.

Design & setting

A quantitative online questionnaire collected from 1100 people with gout from 14 countries within Europe.

Method

Patients were recruited to complete an online survey via healthcare professional (HCP) referral, patient associations, or market research panels. Patients were included if they had been diagnosed with gout by a physician. Prior to commencement, patients were made aware that this study was sponsored by Grünenthal. The responses collected were collated and analyses were performed.

Results

Patients had an average of 2.9 gout flares within a 12-month period. Although 79% of patients were satisfied with treatment, inadequate gout control was also reported by 71% of patients. Furthermore, 84% experienced moderate-to-severe pain with their most recent flare. Of those who acknowledged treatment dissatisfaction, only 24% discussed other options with their GP. Most patients reported irregular follow-up and serum uric acid (sUA) monitoring. In addition, loss of belief that more can be done was a key barrier for patients.

Conclusion

Patients reported severe pain and social burden, coupled with low treatment expectation and lack of awareness of target sUA. Education around knowing and reaching sUA target is needed so that patients can receive and GPs can deliver higher quality management.

Massive Gouty Tophi Presenting as Pseudotumor of the Elbow: A Rare Presentation

Gout is a systemic metabolic disorder characterized by hyperuricemia and deposition of monosodium urate crystals in joints and other extra-articular tissues. Poorly controlled cases progress to chronic gout with tophi, which can sometimes assume massive sizes. We report one such case of a 39-year-old male with poorly controlled polyarticular tophaceous gout presenting with a massive swelling of the left elbow simulating a soft tissue tumor. Subsequent investigations confirmed it to be a massive tophus which was then surgically excised, as the mass was not responding to the medical management. At the latest follow-up after two years, the patient has full function of the elbow and gout is well controlled with medications.

Intake of selected foods and beverages and serum uric acid levels in adults: ELSA-Brasil (2008–2010)

Objective:

To investigate the association between the intake of selected food groups and beverages and serum uric acid (UA).

Design:

Cross-sectional study using the baseline data (2008–2010) from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Food intake was assessed by food frequency questionnaire with 114 items. Linear and logistic regressions investigated the associations between the daily intake of each food group (servings/d) and UA (mg/dl) and hyperuricemia (UA ≥ 6·8 mg/dl), respectively. All the analyses were adjusted for potential confounders, energy intake and all food groups.

Setting:

Teaching and research institutions from six Brazilians states.

Subjects:

The participants were 14 320 active and retired civil servants, aged 35–74 years.

Results:

Higher intake of dairy products was associated with lower serum UA levels in both sexes, with a statistical dose-response gradient. High meat intake was associated with high UA only in women, and high intake of organ meats, in men. Intake of fish and fruits, vegetables and legumes were not associated with serum UA. In men, moderate and high intake of alcoholic beverages, specifically beer and spirits, but not wine, increased UA. In women, only high intake of alcoholic beverages, specifically beer, was associated with increased serum UA. Similar associations were seen for hyperuricemia.

Conclusions:

Results suggest a potential beneficial role of dairy products consumption on UA levels. The association between alcohol intake and UA differed according to type of beverage and between sexes. Results reinforce the need to consider the whole diet in the analysis and to conduct sex stratified analysis.

Prescribing patterns and healthcare costs of gout

OBJECTIVE/METHODS

The Longitudinal Health Insurance Database (LHID) 2010 was used to identify gout cases and their number of gout flares.

RESULTS

Out of 21,376 gout patients, a total of 3561 (16.7%) had frequent gout flares (≥3 gout flares/year). Average all-cause healthcare utilization (35.9 visits vs. 30.7 visits; p < .001) and gout-related utilization (22.7 visits vs. 15.6 visits; p < .001) were higher in frequent gout flare patients than in those with infrequent gout flares. The median gout-related cost (USD $369 vs. $285; p < .001), but not all-cause costs (p = .25), were higher in frequent gout flare patients compared to the infrequent group. Over 55.8% of the flares were treated with colchicine + NSAIDs.

CONCLUSIONS

In conclusion, patients with frequent gout flares had higher healthcare utilization and gout-related healthcare costs. Colchicine + NSAIDs are commonly used therapy for gout flare.

Update on the prevention and treatment of tumor lysis syndrome

Tumor lysis syndrome is a constellation of metabolic derangements seen when tumor cells die and release their intracellular contents into the systemic circulation. Hyperkalemia, hyperphosphatemia, hypocalcemia, and hyperuricemia may lead to severe organ dysfunction and even death. Tumor lysis syndrome is classically considered a complication of successful cancer treatment, but it can also occur in untreated malignancies characterized by rapid proliferation. In this review, we cover the types of cancers and chemo- and immunotherapies associated with tumor lysis syndrome, the mechanisms by which severe metabolic derangements can develop, and the available treatments.

Effect of Giving Celecoxib on Uric Acid Level on Mice

Celecoxib is a breakthrough for pain relievers under the trade name Celebrex�, which is a Non-Steroid Anti-Inflammatory drug with its activity as an analgesic, antipyretic and anti-inflammatory. The purpose of this study was to find out the effect of celecoxib on blood uric acid levels of female white mice was induced with fresh cow liver extract. Experimental animals were divided into five groups, namely the control group (-), the control group (+) and the three dose groups, respectively 0.26, 0.52 and 1.04 mg/20 g. Observations were made on 7, 14 and 21 days with the Enzymatic Photometric method. The results showed that administration of celecoxib suspension at a dose of 0.26, 0.52 and 1.04 mg/20 g did not affect blood uric acid levels when compared with controls (P> 0.05).

Verinurad combined with febuxostat in Japanese adults with gout or asymptomatic hyperuricaemia: a phase 2a, open-label study

Objectives

Verinurad (RDEA3170) is a high-affinity inhibitor of the URAT1 transporter in clinical development for treating gout and asymptomatic hyperuricaemia. The aim of this Phase 2a, randomized, open-label study was to investigate the multiple-dose pharmacodynamics, pharmacokinetics and safety of oral verinurad combined with febuxostat vs febuxostat alone and verinurad alone.

Methods

Japanese male subjects aged 21–65 years with gout (n = 37) or asymptomatic hyperuricaemia (n = 35) and serum urate (sUA) ⩾8 mg/dl were randomized to febuxostat (10, 20, 40 mg) in combination with verinurad (2.5–10 mg), verinurad alone (2.5–15 mg), febuxostat alone (10, 20, 40 mg) or benzbromarone alone (50 mg). There were four treatment periods per cohort and each treatment period was 7 days. Study drugs were administered once-daily after breakfast. Plasma, serum and urine samples were measured at pre-set intervals on days –1, 7, 14, 21 and 28.

Results

Verinurad combined with febuxostat decreased sUA in dose-dependent manner, providing greater sUA lowering than febuxostat alone at the same dose (P < 0.001). Urinary uric acid excretion rate was increased by verinurad, reduced by febuxostat and comparable to baseline for verinurad combined with febuxostat. Verinurad from 2.5 mg to 15 mg was well tolerated, with no withdrawals due to adverse events. Laboratory assessments showed no clinically meaningful changes during combination treatment.

Conclusion

Verinurad combined with febuxostat decreased sUA dose-dependently while maintaining uric acid excretion similar to baseline. All dose combinations of verinurad and febuxostat were generally well tolerated. These data support continued investigation of oral verinurad in patients with gout.

Trial registration

ClinicalTrials.gov, https://clinicaltrials.gov, NCT02317861

Change gout: how to deal with this "silently-developing killer" in everyday clinical practice

BACKGROUND

Despite being regarded as an easily-treatable disease, gout diagnosis and management can be challenging.

REVIEW

This review discusses current issues in gout management and proposes some potential solutions. Gout diagnosis should be reached as early as possible and often requires specific tests, such as synovial fluid analysis or imaging techniques that are not available in most centers, leaving healthcare professionals to rely only on clinical presentations and their experience. In addition, gout management requires the evaluation of multiple aspects, such as monitoring of serum uric acid (sUA) level (which should be reduced to <6 mg/dL) to ensure adherence and efficacy of treatment, evaluation of patient's risk profile and comorbidities, and continuous assessments to manage clinical manifestations. An important premise in gout management is non-pharmacological intervention; however, pharmacological urate-lowering therapy is crucial for an optimal control of the disease. Available options include xanthine-oxidase inhibitors (XOI), targeting uric acid overproduction, and uricosuric agents which target the predominant cause of hyperuricemia (under-excretion). Among these, lesinurad is the novel uricosuric agent to be used in combination with XOI in patients with gout not adequately controlled with XOI alone, which can further contribute to the control of hyperuricemia in gout.

CONCLUSIONS

Multidisciplinary management is crucial for the diagnosis and treatment of gout, in order to ensure treatment continuity and improve management. This review, therefore, advises that educational activities for General Practitioners and specialists should be implemented to help raise awareness on gout diagnosis, monitoring, and treatment.

Physiology of Hyperuricemia and Urate-Lowering Treatments

Gout is the most common form of inflammatory arthritis and is a multifactorial disease typically characterized by hyperuricemia and monosodium urate crystal deposition predominantly in, but not limited to, the joints and the urinary tract. The prevalence of gout and hyperuricemia has increased in developed countries over the past two decades and research into the area has become progressively more active. We review the current field of knowledge with emphasis on active areas of hyperuricemia research including the underlying physiology, genetics and epidemiology, with a focus on studies which suggest association of hyperuricemia with common comorbidities including cardiovascular disease, renal insufficiency, metabolic syndrome and diabetes. Finally, we discuss current therapies and emerging drug discovery efforts aimed at delivering an optimized clinical treatment strategy.

Transethosomal gels as carriers for the transdermal delivery of colchicine: statistical optimization, characterization, and ex vivo evaluation

Introduction

Colchicine is used for the treatment of gout, pseudo-gout, familial Mediterranean fever, and many other illnesses. Its oral administration is associated with poor bioavailability and severe gastrointestinal side effects. The drug is also known to have a low therapeutic index. Thus to overcome these drawbacks, the transdermal delivery of colchicine was investigated using transethosomal gels as potential carriers.

Methods

Colchicine-loaded transethosomes (TEs) were prepared by the cold method and statistically optimized using three sets of 24 factorial design experiments. The optimized formulations were incorporated into Carbopol 940^® gel base. The prepared colchicine-loaded transethosomal gels were further characterized for vesicular size, dispersity, zeta potential, drug content, pH, viscosity, yield, rheological behavior, and ex vivo skin permeation through Sprague Dawley rats’ back skin.

Results

The results showed that the colchicine-loaded TEs had aspherical irregular shape, nanometric size range, and high entrapment efficiency. All the formulated gels exhibited non-Newtonian plastic flow without thixotropy. Colchicine-loaded transethosomal gels were able to significantly enhance the skin permeation parameters of the drug in comparison to the non-ethosomal gel.

Conclusion

These findings suggested that the transethosomal gels are promising carriers for the transdermal delivery of colchicine, providing an alternative route for drug administration.

Nanomedicine: is it lost in translation?

By the end of 2017 more than 200,000 scientific research articles had been published about nanomedicine. Out of this vast number only a few of the reported nanoconstructs reached clinical trials for various applications, including the diagnosis and treatment of several cancers, and the treatment of infections and other non-cancerous diseases. 30 years after the pioneering work in this field of research, the low product yield at the end of research pipeline leads to a question that is asked by many: 'had nanomedicine been lost in translation?' In this review, we will discuss the landscape of nanomedicine regarding cancer treatment and miscellaneous applications as well as some obstacles toward full utilization of this powerful therapeutic tool and suggest a few solutions to improve the current translational value of nanomedicine research.

Management of gout and hyperuricemia: Multidisciplinary consensus in Taiwan

Gout is an inflammatory disease manifested by the deposition of monosodium urate (MSU) crystals in joints, cartilage, synovial bursa, tendons or soft tissues. Gout is not a new disease, which was first documented nearly 5,000 years ago. The prevalence of gout has increased globally in recent years, imposing great disease burden worldwide. Moreover, gout or hyperuricemia is clearly associated with a variety of comorbidities, including cardiovascular diseases, chronic kidney disease, urolithiasis, metabolic syndrome, diabetes mellitus, thyroid dysfunction, and psoriasis. To prevent acute arthritis attacks and complications, earlier use of pharmacotherapeutic treatment should be considered, and patients with hyperuricemia and previous episodes of acute gouty arthritis should receive long-term urate-lowering treatment. Urate-lowering drugs should be used during the inter-critical and chronic stages to prevent recurrent gout attacks, which may elicit gradual resolution of tophi. The goal of urate-lowering therapy should aim to maintain serum uric acid (sUA) level <6.0 mg/dL. For patients with tophi, the initial goal can be set at lowering sUA to <5.0 mg/dL to promote tophi dissolution. The goal of this consensus paper was to improve gout and hyperuricemia management at a more comprehensive level. The content of this consensus paper was developed based on local epidemiology and current clinical practice, as well as consensuses from two multidisciplinary meetings and recommendations from Taiwan Guideline for the Management of Gout and Hyperuricemia.

Gout: An old disease in new perspective - A review

Gout is a picturesque presentation of uric acid disturbance. It is the most well understood and described type of arthritis. Its epidemiology is studied. New insights into the pathophysiology of hyperuricemia and gouty arthritis; acute and chronic allow for an even better understanding of the disease. The role of genetic predisposition is becoming more evident. The clinical picture of gout is divided into asymptomatic hyperuricemia, acute gouty arthritis, intercritical period, and chronic tophaceous gout. Diagnosis is based on laboratory and radiological features. The gold standard of diagnosis is identification of characteristic MSU crystals in the synovial fluid using polarized light microscopy. Imaging modalities include conventional radiography, ultrasonography, conventional CT, Dual-Energy CT, Magnetic Resonance Imaging, nuclear scintigraphy, and positron emission tomography. There is remarkable progress in the application of ultrasonography and Dual-Energy CT which is bound to influence the diagnosis, staging, follow-up, and clinical research in the field. Management of gout includes management of flares, chronic gout and prevention of flares, as well as management of comorbidities. Newer drugs in the pharmacological armamentarium are proving successful and supplement older ones. Other important points in its management include patient education, diet and life style changes, as well as cessation of hyperuricemic drugs.

Critical revision of the medical treatment of gout in Brazil

Gout is considered the most common form of inflammatory arthritis in men over 40 years. The authors present a brief review of the current treatment of gout and discuss the existing pharmacological limitations in Brazil for the treatment of this disease. Although allopurinol is still the main drug administered for decreasing serum levels of uric acid in gout patients in this country, the authors also present data that show a great opportunity for the Brazilian drug market for the treatment of hyperuricemia and gout and especially for patients using private and public (SUS) health care systems.

Design of Organic Macrocycle-Modified Iron Oxide Nanoparticles for Drug Delivery

Paul Ehrlich's vision of a "magic bullet" cure for disease inspires the modern design of nanocarriers whose purpose is to deliver drug cargo to specific sites in the body while circumventing endogenous immunological clearance mechanisms. Iron oxide nanoparticles (IONPs) have emerged as particularly promising nanocarriers because of their biodegradability, ability to be guided magnetically to sites of pathology, mediation of hyperthermic therapy, and imaging capabilities. In this review, we focus on the design and drug-delivery aspects of IONPs coated with organic macrocycles (crown ethers, cyclodextrins, calix[n]arenes, cucurbit[n]urils, or pillar[n]arenes), which, by means of reversible complexation, allow for the convenient loading and release of drug molecules. Macrocycles can be attached to IONPs indirectly or directly. Indirect attachment requires the use of small organic linking molecules or conjugation to shell materials. Direct attachment requires neither. We discuss in detail drug release from the macrocycles, highlighting mechanisms that depend on external stimuli such as changes in pH, the competitive binding of ions or small molecules, or the application of ultrasound or electromagnetic radiation.

The Role of miRNAs in Common Inflammatory Arthropathies: Osteoarthritis and Gouty Arthritis

MicroRNAs (miRNAs) are small, non-coding RNA species that are highly evolutionarily conserved, from higher invertebrates to man. Up to 1000 miRNAs have been identified in human cells thus far, where they are key regulators of the expression of numerous targets at the post-transcriptional level. They are implicated in various processes, including cell differentiation, metabolism, and inflammation. An expanding list of miRNAs is known to be involved in the pathogenesis of common, non-autoimmune inflammatory diseases. Interestingly, osteoarthritis (OA) is now being conceptualized as a metabolic disease, as there is a correlation among hyperuricemia and metabolic syndrome (MetS). Experimental evidence suggests that metabolic deregulation is a commonality between these different pathological entities, and that miRNAs are key players in the modulation of metabolic routes. In light of these findings, this review discusses the role of miRNAs in OA and gouty arthritis, as well as the possible therapeutic targetability of miRNAs in these diseases.

Gout: a comprehensive review

The prevalence of gout in the US population is steadily increasing. Genome-wide research has found several variants of DNA sequences that predispose patients to irregular uric acid metabolism. Comorbidities linked to gout include obesity and cardiovascular disease. Though the formal diagnosis is made with arthrocentesis and subsequent analysis, CT and ultrasound findings supplement the diagnosis and monitor disease management. Newer immunologic agents are available for patients whose disease is refractory to standard therapy.

Allopurinol and oxypurinol promote osteoblast differentiation and increase bone formation

Allopurinol and its active metabolite, oxypurinol are widely used in the treatment of gout and hyperuricemia. They inhibit xanthine oxidase (XO) an enzyme in the purine degradation pathway that converts xanthine to uric acid. This investigation examined the effect of allopurinol and oxypurinol on bone formation, cell number and viability, gene expression and enzyme activity in differentiating and mature, bone-forming osteoblasts. Although mRNA expression remained relatively constant, XO activity decreased over time with mature osteoblasts displaying reduced levels of uric acid (20% decrease). Treatment with allopurinol and oxypurinol (0.1-1 µM) reduced XO activity by up to 30%. At these concentrations, allopurinol and oxypurinol increased bone formation by osteoblasts ~4-fold and ~3-fold, respectively. Cell number and viability were unaffected. Both drugs increased tissue non-specific alkaline phosphatase (TNAP) activity up to 65%. Osteocalcin and TNAP mRNA expression was increased, 5-fold and 2-fold, respectively. Expression of NPP1, the enzyme responsible for generating the mineralisation inhibitor, pyrophosphate, was decreased 5-fold. Col1α1 mRNA expression and soluble collagen levels were unchanged. Osteoclast formation and resorptive activity were not affected by treatment with allopurinol or oxypurinol. Our data suggest that inhibition of XO activity promotes osteoblast differentiation, leading to increased bone formation in vitro.

The eye and the skin in nonendocrine metabolic disorders

As metabolism is controlled by the input of genes and the environment, metabolic disorders result from some disturbance in the interaction between genes and environmental factors. Many metabolic disorders consist in congenital enzyme deficiencies, also known as "inborn errors of metabolism," that may be disabling or cause severe illness and death and are predominantly inherited in an autosomal recessive fashion. The deposit in cells and tissues of storage substances from errors in metabolic processes may produce a wide variety of disorders affecting different organs and functions, with different degrees of severity, and often present around the time of birth or early childhood. Distinctive ocular and skin manifestations accompany many metabolic diseases and may provide clues for their diagnosis and evolution.

Significance of the initiation time of urate-lowering therapy in gout patients: A retrospective research

OBJECTIVE

To evaluate the efficacy and safety of the initiation time of urate-lowering treatments (ULT) in gout patients.

METHOD

We retrospectively reviewed patients who were diagnosed with gout and were treated with ULT for at least 3 years. They were divided into two groups: group 1: 123 patients initiating ULT during an acute attack of gout; group 2: 457 patients prescribed ULT after an acute attack. Both demographic and clinical characteristics associated with gout were analyzed.

RESULTS

Comparing patients in group 1 versus group 2: the former exhibited a shorter duration of gout (6.3±2.1 vs. 8.9±3.3 years). At the baseline, there was no significant difference in mean serum urate (SU; 7.8±1.4mg/dL vs. 7.9±1.9mg/dL, respectively). SU target levels (<6.0mg/dL) were achieved by 66.7 and 65.6% of the patients, respectively. The duration from initiation of ULT until the SU target was attained was lower in group 1 than in group 2. During the first 12 weeks, patients on ULT in group 1 had higher attack rates than those in group 2. The incidence of chronic kidney disease increased in percentage in group 1 was lower than in group 2.

CONCLUSIONS

Our survey revealed that in patients experiencing acute gout, initiation of ULT decreased the time required to reach the target SU and the incidence of CKD, but the attack rate was greater in the first 12 weeks.

Physician adherence to ACR gout treatment guidelines: perception versus practice

BACKGROUND

In October 2012, the American College of Rheumatology (ACR) published recommendations for chronic gout treatment goals and pharmacotherapy.

OBJECTIVES

Identify potential gaps between real-world chronic gout treatment, ACR guideline recommendations, and physicians' perceived guideline adherence by evaluating records of patients classified as having "higher" and "lower" guideline adherence as defined by the investigators.

METHODS

A comprehensive quantitative survey was administered between February 11 and February 22, 2013, to physicians treating patients with gout; the survey included a patient record chart review informed by prior qualitative interviews. Eight criteria from the ACR gout management guidelines were used to compose the survey. To assess ACR guideline adherence, information from records of patients with chronic gout treated by primary care physicians (PCPs) and rheumatologists was scored from 0 (no adherence) to 8 (total adherence), in accordance with ACR guideline recommendations. Physicians also indicated how closely they believed patient treatment followed current guidelines on a 10-point scale.

RESULTS

Of the 350 records of patients with chronic gout, all but 3 PCP patients were adherent on ≥ 1 guideline recommendation, but nearly all patients could be considered nonadherent, considering all potential recommendations. Patients with chronic gout treated by rheumatologists tended to be managed more closely to ACR guidelines than patients treated by PCPs (mean scores: rheumatologists 5.8/8 ± 1.7 vs 4.3/8 ± 1.7 for PCPs). Among patients classified as having "higher adherence" based on adherence scores, there was low adherence on first-line urate lowering therapy dose, acute prophylaxis dosing, and length of prophylaxis treatment. Among PCPs and rheumatologists, there was a disparity between how closely physicians believed patient treatment followed guidelines and actual adherence with ACR guidelines based on adherence scores. For 16.4% of patients treated by PCPs and 18.4% of patients seen by rheumatologists, physicians believed they closely followed ACR guidelines (score of 8-10/10) for each patient; but in actuality, adherence was lower.

CONCLUSION

Although adherence with ACR guidelines is higher among rheumatologists than PCPs in treating patients with gout, overall adherence could be improved by both specialties.

Cost-effectiveness analysis of HLA-B*5801 testing in preventing allopurinol-induced SJS/TEN in Thai population

BACKGROUND

Stevens-Johnson syndrome (SJS) and Toxic Epidermal Necrolysis (TEN), caused by allopurinol therapy, are strongly associated with the human leukocyte antigen (HLA), HLA-B*5801. Identification of HLA-B*5801 genotype before prescribing allopurinol offers the possibility of avoiding allopurinol-induced SJS/TEN. As there is a paucity of evidence about economic value of such testing, this study aims to determine the cost-effectiveness of HLA-B*5801 testing compared with usual care (no genetic testing) before allopurinol administration in Thailand.

METHODS AND FINDING

A decision analytical and Markov model was used to estimate life time costs and outcomes represented as quality adjusted life years (QALYs) gained. The model was populated with relevant information of the association between gene and allopurinol-induced SJS/TEN, test characteristics, costs, and epidemiologic data for Thailand from a societal perspective. Input data were obtained from the literature and a retrospective database analysis. The results were expressed as incremental cost per QALY gained. A base-case analysis was performed for patients at age 30. A series of sensitivity analyses including scenario, one-way, and probabilistic sensitivity analyses were constructed to explore the robustness of the findings. Based on a hypothetical cohort of 1,000 patients, the incremental total cost was 923,919 THB (USD 29,804) and incremental QALY was 5.89 with an ICER of 156,937.04 THB (USD 5,062) per QALY gained. The cost of gout management, incidence of SJS/TEN, case fatality rate of SJS/TEN, and cost of genetic testing are considered very influential parameters on the cost-effectiveness value of HLA-B*5801 testing.

CONCLUSIONS

The genetic testing for HLA-B*5801 before allopurinol administration is considered a highly potential cost-effective intervention in Thailand. The findings are sensitive to a number of factors. In addition to cost-effectiveness findings, consideration of other factors including ethical, legal, and social implications is needed for an informed policy decision making.

Analysis of patents on anti-gout therapies issued in China

INTRODUCTION

The incidence of gout and hyperuricemia has been increasing. The demand for new anti-gout therapies today presents exciting opportunities to organizations and individuals offering such products.

AREAS COVERED

This review analyzes the patents of anti-gout products to help pharmaceutical companies and individuals in the patenting of potential candidate drugs for gout treatment in China.

EXPERT OPINION

In this review, 786 patents were found, among which, 215 are in the protection period. The latter group of patents includes 183 patents for traditional Chinese medicines (TCM, 85%), 30 for synthetic compounds (14%) and 2 for combinations of synthetic compounds and TCM (CST). Among the TCM patents, 84% contain various dosage formulae for different Chinese medicines, 13% are herbal extracts and only 7 patents are from herbal extract derivatives. Synthetic compound patents mainly target xanthine oxidase, urate transporter 1 and uric acid oxidase. Searching for new targets and drugs acting on multiple targets should provide a new stimulus in the field of synthetic compound patents. CST has the smallest proportion of Chinese anti-gout patents, although it is still in the test stage and has not been widely accepted, but has provided a new direction for the field of anti-gout patents.

Xanthine oxido-reductase, free radicals and cardiovascular disease. A critical review

Free radical mediated pathologies occupy a special place in medical semiology and in mechanistic interpretation of diseases. Free radicals, or better reactive oxygen species (ROS) or reactive nitrogen species (RNS) play also an important role in cell signaling. This is the basis of the ambivalent (Jekyll-Hyde) situation of ROS in biology and pathology. Aging itself is attributed by a popular theory to free radicals. A number of ROS-scavenging substances and procedures were described without however reaching credibility for their therapeutic value. An interesting exception is the xanthine oxido-reductase produced ROS and their role in cardiovascular disease. Allopurinol inhibition of xanthine oxido-reductase was shown to be efficient in some cases of cardiovascular diseases. Another important aspect of xanthine oxido-reductase produced ROS is their antibacterial capacity considered to be of importance with newborns fed on milk rich in this enzyme as well as at the gastrointestinal barrier. This ambivalent role of xanthine oxido-reductase justifies this review on the basic enzymatic mechanisms involved, derived ROS production, their role in the above mentioned biological processes and especially the interest of the inhibition of this enzyme as a preventive or curative measure in some cardiovascular pathologies.