Allopurinol hypersensitivity: Pathogenesis and prevention

Eupatilin inhibits xanthine oxidase in vitro and attenuates hyperuricemia and renal injury in vivo

Uric acid (UA) is the final metabolite of purines in the liver that can cause hyperuricemia at high levels. The kidneys are the main excretory organs for UA. The excessive accumulation of UA in the kidneys causes the development of hyperuricemia that often leads to renal injury. Eupatilin (Eup) is a flavonoid natural product that possesses various pharmacological properties such as antioxidant, anti-cancer, and anti-inflammatory. We were interested in exploring the potential role of Eup in lowering UA and nephroprotective. We initially investigated the effects of Eup on xanthin oxidase (XOD) activity in vitro, followed by investigating its ability to lower UA levels, anti-inflammatory effects, nephroprotective effects, and the underlying mechanisms using hyperuricemia rats sustained at high UA level. The results showed that Eup had an inhibitory effect on XOD activity in vitro and significantly reduced serum UA, creatinine, BUN, IL-1β and IL-6 levels in hyperuricemic rats, ameliorating inflammation, renal oxidative stress and pathological injury. Furthermore, Eup inhibited ADA and XOD enzyme activities in the liver and serum and modulated GLUT9, URAT1 and ABCG2 protein expression in the kidneys and ileum. Our findings provide a scientific basis for suggesting Eup as an option for a potential treatment for hyperuricemia.

Agents for the Treatment of Gout: Current Advances and Future Perspectives

Gout is characterized by hyperuricemia and the deposition of monosodium urate (MSU) crystals around joints. Despite the availability of several drugs on the market, its treatment remains challenging owing to the notable side effects, such as hepatorenal toxicity and cardiovascular complications, that are associated with most existing agents. This perspective aims to summarize the current research progress in the development of antigout agents, particularly focusing on xanthine oxidase (XO) and urate anion transporter 1 (URAT1) inhibitors from a medicinal chemistry viewpoint and their preliminary structure-activity relationships (SARs). This perspective provides valuable insights and theoretical guidance to medicinal chemists for the discovery of antigout agents with novel chemical structures, better efficiency, and lower toxicity.

Effects of Processing Conditions and Simulated Digestion In Vitro on the Antioxidant Activity, Inhibition of Xanthine Oxidase and Bioaccessibility of Epicatechin Gallate

The bioactivity and gastrointestinal stability of epicatechin gallate (ECG) may be affected by processing conditions. Results showed that the antioxidant ability and inhibitory activity on xanthine oxidase (XO) of ECG were higher at low pH values. Appropriate microwave and heating treatments improved the antioxidant (the scavenging rate increased from 71.75% to 92.71% and 80.88% under the microwave and heating treatments) and XO inhibitory activity (the inhibitory rate increased from 47.11% to 56.89% and 51.85% at the microwave and heating treatments) of ECG. The treated ECG led to a more compact structure of XO. Moreover, there may be synergistic antioxidant and inhibitory effects between ECG and its degradation products. The bioaccessibility of ECG after simulated digestion was untreated > microwave > heating, and the microwave-treated ECG still had good XO inhibitory activity after digestion. These findings may provide some significant information for the development of functional foods enriched in catechins.

Emodin, a Natural Anthraquinone, Increases Uric Acid Excretion in Rats with Potassium Oxonate-Induced Hyperuricemia

The treatment of hyperuricemia and gout is mostly based on lowering serum uric acid levels using drugs, such as allopurinol, or increasing urinary excretion of uric acid. However, some patients still experience adverse reactions to allopurinol and turn to Chinese medicine as an alternative. Therefore, it is crucial to design a preclinical study to obtain more convincing data on the treatment of hyperuricemia and gout with Chinese medicine. This study aimed to explore the therapeutic effect of emodin, a Chinese herbal extract, in a rat model of hyperuricemia and gout. In this study, we used 36 Sprague-Dawley rats, which were randomly divided into six groups for experimentation. Hyperuricemia was induced in rats by intraperitoneal injections of potassium oxonate. The efficacy of emodin in reducing serum uric acid levels was demonstrated by comparing the positive control group with groups treated with three different concentrations of emodin. The inflammatory profiles, including interleukin (IL)-1β, IL-6, and tumor necrosis factor-α levels, were unaffected by emodin treatment. In the experimental results, it was observed that the serum uric acid concentration in the vehicle control group was 1.80 ± 1.14, while the concentrations in the moderate and high concentration emodin groups were 1.18 ± 0.23 and 1.12 ± 0.57, resulting in no significant difference in uric acid concentration between these treatment groups and the control group, indicating that emodin has a therapeutic effect on hyperuricemia. The increase in the fractional excretion of uric acid (FEUA) demonstrated that emodin promoted urinary uric acid excretion without significantly affecting the inflammatory profile. Thus, emodin reduced the serum uric acid concentration to achieve effective treatment of hyperuricemia and gout by increasing urinary excretion. These results were supported by the measured serum uric acid and FEUA levels. Our data have potential implications for the treatment of gout and other types of hyperuricemia in clinical practice.

Fatty Acid-Rich Extract from Holothuria atra for Hyperuricemia via Expressions Modulation of GLUT9a and GLUT9b in Rat Model

An edible sea cucumber Holothuria atra has been hypothesized to have medicinal benefits against hyperuricemia owing to its bioactive compounds, including mono- and poly-unsaturated fatty acids. Herein, we aimed to investigate the fatty acids-rich extract produced from H. atra to treat hyperuricemic rats (Rattus novergicus). The extraction was carried out using n-hexane solvent and then administered to potassium oxonate-induced hyperuricemic rats, with allopurinol acting as a positive control. The extract (50, 100, 150 mg/kg body weight) and allopurinol (10 mg/kg) were administered QD through an oral route using a nasogastric tube. Serum uric acid, creatinine, aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and blood urea nitrogen of the abdominal aortic blood were investigated. Our results suggested that the extract was rich in polyunsaturated (arachidonic acid) and monounsaturated fatty acids (oleic acid), in which its administration of 150 mg/kg could significantly reduce serum uric acid (p < 0.001), AST (p = 0.001), and ALT (p = 0.0302). The anti-hyperuricemic activity could be associated with the modulation of GLUT9 by the H. atra extract. In conclusion, the n-hexane extract from H. atra is a potential serum uric acid-lowering agent targeting GLUT9, where further investigations are crucially warranted.

Lactobacillus acidophilus Fermented Dandelion Improves Hyperuricemia and Regulates Gut Microbiota

Foodborne prevention and treatment of hyperuricemia (HUA) has received widespread attention. Lactic acid bacteria (LAB) can improve intestinal function, while traditional medicine dandelion has the functions of detoxification and detumescence. Whether LAB fermented dandelion has any effects on HUA and the underlying mechanism is not clear. To address these questions, Lactobacillus acidophilus was selected or maximal xanthine oxidase activity. The effect of Lactobacillus acidophilus fermented dandelion (LAFD) on uric acid metabolism was evaluated by the HUA mouse model. Expression levels of UA, BUN, CRE, XOD, and inflammatory factors in serum were detected. Paraffin sections and staining were used to observe the kidney and small intestine, and mRNA expression of GLUT9, URAT1, OAT1, and ABCG2 related to uric acid metabolism were investigated. Furthermore, the intestinal flora was studied by contents of the cecum and high throughput 16S rRNA sequencing. The results showed that LAFD had a significant inhibitory effect on XOD in vitro (p < 0.01). LAFD could reduce the levels of UA, BUN, CRE, XOD, IL-1 β, IL-6, and TNF- α in serum (p < 0.05), thus inhibiting inflammatory reaction, and reducing UA by decreasing the mRNA expression of GLUT9, URAT1 in kidney and increasing the mRNA expression of OAT1 and ABCG2 in kidney and small intestine (p < 0.05). In addition, the 16S rRNA gene sequencing analysis demonstrated that LAFD treatment can help restore the imbalance of the intestinal microbial ecosystem and reverse the changes in Bacterodietes/Firmicutes, Muribaculaceae, Lachnospiraceae in mice with HUA. It is suggested that the mechanism of LAFD in treating HUA may be related to the regulation of the mRNA expressions of GLUT9, URAT1, OAT1, and ABCG2 in the kidney and small intestine, as well as the regulation of intestinal flora, which provides the experimental basis for the development of new plant fermented products.

Initiation Dose of Allopurinol and the Risk of Severe Cutaneous Reactions in Older Adults With CKD: A Population-Based Cohort Study

RATIONALE & OBJECTIVE

Allopurinol should be started at lower doses in patients with chronic kidney disease (CKD) to avoid adverse effects. We examined the risk of severe cutaneous reactions in older adults with CKD who were newly prescribed allopurinol at varied doses.

STUDY DESIGN

Population-based cohort study using linked health care databases.

SETTING & PARTICIPANTS

Patients in Ontario, Canada (2008-2019) aged ≥66 years, with an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m², and who were new users of allopurinol.

EXPOSURE

A new prescription for allopurinol >100 mg/d versus a dose ≤100 mg/d.

OUTCOME

The primary outcome was a hospital visit with a severe cutaneous reaction within 180 days of starting allopurinol. Secondary outcomes included all-cause hospitalization and all-cause mortality.

ANALYTICAL APPROACH

The exposure and referent groups were balanced on indicators of baseline health using inverse probability of treatment weighting on the propensity score. Weighted risk ratios (RR) were obtained using modified Poisson regression and weighted risk differences (RD) using binomial regression.

RESULTS

Of 47,315 patients (median age, 76 years; median eGFR, 45 mL/min/1.73 m²), 55% started allopurinol at >100 mg/d. Starting allopurinol at >100 versus ≤100 mg/d was associated with an increased risk of a severe cutaneous reaction: number of events (weighted), 103 of 25,802 (0.40%) versus 46 of 25,816 (0.18%), respectively (weighted RR, 2.25 [95% CI, 1.50-3.37]; weighted RD, 0.22% [95% CI, 0.12%-0.32%]. Starting allopurinol at >100 versus ≤100 mg/d was associated with an increased risk of all-cause hospitalization but not with all-cause mortality.

LIMITATIONS

This study was underpowered to detect risk differences in the association of allopurinol dose with outcomes across eGFR categories (ie, 45-59, 30-44, and <30 mL/min/1.73 m²).

CONCLUSIONS

Older patients with CKD who started allopurinol at >100 mg/d versus ≤100 mg/d were twice as likely to visit a hospital with a severe cutaneous reaction in the next 180 days.

Allopurinol-induced Stevens-Johnson syndrome and toxic epidermal necrolysis: Signal detection and preventability from Vietnam National pharmacovigilance database

WHAT IS KNOWN AND OBJECTIVE

Allopurinol, the first-line medication for hyperuricemia is well-known for its association with severe cutaneous adverse reactions, especially Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). In the current study, we analysed the Vietnamese spontaneous reporting database to identify signals and preventability of allopurinol-induced SJS/TEN in Vietnam from 2010 to 2019.

METHODS

Signal generation was assessed using the case/non-case method. Reporting odds ratios (RORs) and 95% confidence intervals (95% CI) were calculated.

RESULTS

Among 72,822 spontaneous ADR reports submitted to the Vietnam National Drug Information and Adverse Drug Reaction Monitoring Centre, 392 reports were on SJS/TEN, of which, 65 cases (16.6%) were related to allopurinol. The signals of allopurinol-induced SJS/TEN in Vietnam started in 2014 (ROR of 3.531, 95% CI: 1.830-6.810) and annually increased until 2019 (ROR of 11.923, 95% CI: 8.508-16.710). The preventability assessment showed that no allopurinol-induced SJS/TEN case was definitely unpreventable. 61.6% of the SJS/TEN cases were avoidable because they were associated with inappropriate prescribing such as unapproved indications, too high initial dose and even rechallenging in patients with a history of allopurinol allergy.

WHAT IS NEW AND CONCLUSION

The signals of allopurinol-induced SJS/TEN in Vietnam started in 2014 and annually increased until 2019. Our first report specifically focusing on the ADR preventability of allopurinol showed that correction of medical errors relating to prescription could prevent more than 60% of SJS/TEN cases in Vietnamese allopurinol users. This is a feasible and practical solution, provided that there would be a systematic change in both healthcare systems and public awareness.

Review of Urate-Lowering Therapeutics: From the Past to the Future

We reviewed all currently available ULT, as well as any medications in development using following databases: United States Food and Drug Administration (FDA), European Medicines Agency (EMA), Japanese Pharmaceutical and Medical Devices Agency (PMDA), and ClinicalTrials.gov. We identified a total of 36 drugs, including 10 approved drugs, 17 in clinical testing phases, and 9 in preclinical developmental phases. The 26 drugs currently undergoing testing and development include 5 xanthine oxidase inhibitors, 14 uricosurics, 6 recombinant uricases, and one with multiple urate-lowering mechanisms of action. Herein, we reviewed the benefit and risk of each drug summarizing currently available drugs. New trials of uricosuric agents are underway to develop the new indication. New drugs are going on to improve the potency of recombinant uricase and to develop the new route administration of such as oral formulation. This review will provide valuable information on the properties, indications, and limitations of ULTs.

A review of the Phyllanthus genus plants: Their phytochemistry, traditional uses, and potential inhibition of xanthine oxidase

Hyperuricemia is a risk factor for gout and other cardiovascular diseases. One of the therapies used is Allopurinol. Unfortunately, it has unwanted side effects. These conditions made researchers continue to seek and develop alternative treatments from natural products. One of which is from plants of the Phyllanthus genus. One of their contents was polyphenols, especially flavonoids. It is an alternative treatment for hyperuricemia because of its minimal side effects. The flavonoids in this genus were reported to have xanthine oxidase inhibitory: quercetin, kaempferol, rutin, apigenin, luteolin, myricetin, catechin, epicatechin, and epigallocatechin with IC50 values ​​from 0.44 M to &gt; 100μM. The presence of π-π interactions between planar rings A and C on flavones with phe 1009 and phe 914 and the addition of hydroxyl groups on flavonoid compounds plays a crucial role in inhibiting xanthine oxidase.

Cutaneous Adverse Drug Reactions (CADRs)—Statistical Analysis of the Causal Relationship between the Drug, Comorbidities, Cofactors, and the Cutaneous Reaction—A Single-Centered Study

Cutaneous adverse drug reactions (CADRs) are among the most common types of drug hypersensitivity reactions. The purpose of this study was to evaluate the clinical spectrum of CADRs and to determine the causal relationship between drugs, comorbidities, cofactors or concomitant symptoms, and cutaneous reactions. A retrospective hospital-based study was carried out over a period of 10 years at the Department of Dermatology, Sexually Transmitted Diseases and Clinical Immunology at the University of Warmia and Mazury in Olsztyn to record various CADRs, comorbidities, cofactors, and the suspected drug in hospitalized patients. The data were subjected to statistical analysis. CADRs were diagnosed in a total of 140 patients, 32.14% of whom were men and 67.86% of whom were women. The mean age was 66.33 years. The most commonly suspected drugs were Allopurinol 12.86%, Amoxicillin with clavulanic acid 10%, Amoxicillin 9.29%, Paracetamol 6.43%, Metronidazole 5%, and Carbamazepine 5%. Attention should be paid to the possibility of using a substitute for a suspected drug if CADRs arise, or discontinuing a drug that is unjustifiably overused. The results of the present study should also prompt research into a potential treatment that could be implemented concurrently with a drug that has a high predisposition to cause CADRs.

Patch testing in Drug reaction with eosinophilia and systemic symptoms (DRESS): a literature review

The literature on positive patch test results in drug reaction with eosinophilia and systemic symptoms (DRESS) is reviewed. 105 drugs were identified that have together caused 536 positive patch tests in 437 patients suffering from DRESS. By far most reactions (n=145) were caused by carbamazepine, followed by amoxicillin, isoniazid, phenytoin, ethambutol, fluindione, phenobarbital, rifampicin, and ceftriaxone; 43 drugs each caused a single case only. The drug classes causing the highest number of reactions are anticonvulsants (39%), beta-lactam antibiotics (20%), antituberculosis agents (11%), non-beta-lactam antibiotics (6%) and iodinated contrast media (5%). The sensitivity of patch testing (percentage of positive reactions) is high for anticonvulsants (notably carbamazepine), beta-lactam antibiotics (notably amoxicillin) and possibly iodinated contrast media. Allopurinol and sulfasalazine frequently cause DRESS, but never give positive patch tests. Patch testing in DRESS appears to be safe, although mild recurrence of DRESS symptoms, mostly skin reactions, may not be rare. Multiple drug hypersensitivity was found to occur in 16% of all patients, but it is argued that the true frequency is (far) higher. Clinical aspects of DRESS, including diagnosing the disease and identifying culprit drugs (patch tests, intradermal tests, in vitro tests, challenge tests) are also provided, emphasizing the role of patch testing. This article is protected by copyright. All rights reserved.

Allopurinol-induced severe cutaneous adverse reactions in Vietnamese: the role of HLA alleles and other risk factors

Aim: To reveal the association of three class I HLA alleles, including HLA-A*33:03, HLA-B*58:01 and HLA-C*03:02, and allopurinol-induced severe cutaneous adverse reactions (SCARs) in Vietnamese patients. Methods: A case–control study on 100 allopurinol-induced SCARs patients, 183 tolerant controls and 810 population controls was performed. The HLA-A*33:03 and HLA-C*03:02 alleles were detected with the nested allele-specific PCR method; the HLA-B*58:01 allele was detected with the sequence-specific primer PCR method. Results: There were strong associations between HLA-B*58:01 and HLA-C*03:02 and allopurinol-induced SCARs. Specific associations were found between HLA-B*58:01 and Stevens–Johnson syndrome/toxic epidermal necrolysis and between HLA-C*03:02 and drug reaction with eosinophilia and systemic symptoms, with a gene dosage effect. The multivariate regression analysis indicated two significant independent risk factors: HLA-B*58:01/HLA-C*03:02 and estimated glomerular filtration rate <60 ml/min/1.73 m2. The specificity, positive predictive value and negative predictive value of HLA-B*58:01 testing were higher than the HLA-C*03:02 or the multiplex testing, especially in patients with impaired renal function. Conclusion: The results supported pre-treatment HLA-B*58:01 testing in Vietnamese patients with declined renal function to prevent SCARs.

Inhibitory activities of grape bioactive compounds against enzymes linked with human diseases

A quest for identification of novel, safe and efficient natural compounds, as additives in the modern food and cosmetic industries, has been prompted by concerns about toxicity and side effects of synthetic products. Plant phenolic compounds are one of the most documented natural products due to their multifarious biological applications. Grape (Vitis vinifera) is an important source of phenolic compounds such as phenolic acids, tannins, quinones, coumarins and, most importantly, flavonoids/flavones. This review crisply encapsulates enzyme inhibitory activities of various grape polyphenols towards different key human-ailment-associated enzymes: xanthine oxidase (gout), tyrosinase (hyperpigmentation), α-amylase and α-glucosidase (diabetes mellitus), pancreatic lipase (obesity), cholinesterase (Alzheimer's disease), angiotensin i-converting enzymes (hypertension), α-synuclein (Parkinson's disease) and histone deacetylase (various diseases). The review also depicts the enzyme inhibitory mechanism of various grape polyphenols and briefly discusses their stature as potential therapeutic and drug development candidates. KEY POINTS: • Nineteen major bioactive polyphenols from the grape/grape products and their disease targets are presented • Sixty-two important polyphenols as enzyme inhibitors from grape/grape products are presented • A thorough description and graphical presentation of biological significance of polyphenols against various diseases.

Antihyperuricemic Effect of Green Alga Ulva lactuca Ulvan through Regulating Urate Transporters

A novel polysaccharide from Ulva lactuca (ULP) was purified using a Sepharose CL-4B column. Fourier transform infrared spectroscopy, high-performance liquid chromatography, and nuclear magnetic resonance spectroscopy were employed to analyze the structure of ULP. It consisted of rhamnose (Rha), glucuronic acid (GluA), galactose (Gal), and xylose (Xyl) at a molar ratio of 32.75:22.83:1.07:6.46 with the molecular weight of 2.24 × 10⁵ Da. The four major glycosidic residues found in ULP were →2,3)-α-l-Rhap-(1→, →4)-β-d-GlcpA-(1→, →2,6)-β-d-Galp-(1→, and →4)-β-d-Xylp-(1→. The antihyperuricemic activity of ULP was exhibited by detecting related biochemical indexes, urate transporter gene expressions, renal histopathology, and intestinal microbiota shifts. ULP obviously decreased the levels of serum uric acid (UA), blood urea nitrogen, and creatinine, while inhibited serum and hepatic xanthine oxidase activities as well as improved renal injury in hyperuricemic mice. Furthermore, the upregulation of UA excretion genes ABCG2/OAT1 and downregulation of UA resorption genes URAT1 and GLUT9 were detected. In addition, ULP exerted its antihyperuricemic effect through regulating the intestinal microbiome, characterized by elevating the helpful microbial abundance, meanwhile declining the harmful bacterial abundance and restoring the gut microbiome homeostasis. This study demonstrates the antihyperuricemic activity of ULP and its potential effect for the treatment of hyperuricemia-related diseases.

Epicatechin Gallate as Xanthine Oxidase Inhibitor: Inhibitory Kinetics, Binding Characteristics, Synergistic Inhibition, and Action Mechanism

Epicatechin gallate (ECG) is one of the main components of catechins and has multiple bioactivities. In this work, the inhibitory ability and molecular mechanism of ECG on XO were investigated systematically. ECG was determined as a mixed xanthine oxidase (XO) inhibitor with an IC50 value of 19.33 ± 0.45 μM. The promotion of reduced XO and the inhibition of the formation of uric acid by ECG led to a decrease in O2- radical. The stable ECG-XO complex was formed by hydrogen bonds and van der Waals forces, with the binding constant of the magnitude of 104 L mol-1, and ECG influenced the stability of the polypeptide skeleton and resulted in a more compact conformation of XO. Computational simulations further characterized the binding characteristics and revealed that the inhibitory mechanism of ECG on XO was likely that ECG bound to the vicinity of flavin adenine dinucleotide (FAD) and altered the conformation of XO, hindering the entry of substrate and the diffusion of catalytic products. ECG and allopurinol bound to different active sites of XO and exerted a synergistic inhibitory effect through enhancing their binding stability with XO and changing the target amino acid residues of XO. These findings may provide a theoretical basis for the further application of ECG in the fields of food nutrition and functional foods.

The Role of Oxidative Stress in Hyperuricemia and Xanthine Oxidoreductase (XOR) Inhibitors

Uric acid is the end product of purine metabolism in humans. Hyperuricemia is a metabolic disease caused by the increased formation or reduced excretion of serum uric acid (SUA). Alterations in SUA homeostasis have been linked to a number of diseases, and hyperuricemia is the major etiologic factor of gout and has been correlated with metabolic syndrome, cardiovascular disease, diabetes, hypertension, and renal disease. Oxidative stress is usually defined as an imbalance between free radicals and antioxidants in our body and is considered to be one of the main causes of cell damage and the development of disease. Studies have demonstrated that hyperuricemia is closely related to the generation of reactive oxygen species (ROS). In the human body, xanthine oxidoreductase (XOR) catalyzes the oxidative hydroxylation of hypoxanthine to xanthine to uric acid, with the accompanying production of ROS. Therefore, XOR is considered a drug target for the treatment of hyperuricemia and gout. In this review, we discuss the mechanisms of uric acid transport and the development of hyperuricemia, emphasizing the role of oxidative stress in the occurrence and development of hyperuricemia. We also summarize recent advances and new discoveries in XOR inhibitors.

Managing hyperuricemia and gout in chronic kidney disease: a clinical conundrum

PURPOSE OF REVIEW

There is controversy regarding the impact of hyperuricemia on the progression of chronic kidney disease (CKD), and gout remains sub optimally managed in this population. We discuss the prescribing of drugs for the treatment of gout in patients with CKD.

RECENT FINDINGS

There is a lack of consensus from expert guidelines, and prescribers have concerns regarding the risk of adverse reactions from medicines used to treat gout. These situations appear to contribute to suboptimal management of gout in this cohort. Recent data have challenged the role of urate lowering therapy (ULT) in the management of asymptomatic hyperuricemia in CKD.

SUMMARY

ULT should be commenced in all patients with severe, recurrent disease, tophaceous gout and evidence of joint damage. Most international guidelines recommend a treat-to-target approach for the management of gout. In CKD, ULT should be started at low dose with up titration adjusted to serum urate levels, rather than being based on the creatinine clearance. If patients fail first-line therapy, alternative agents are utilized, the specific agent depending on ease of access, burden of disease and other comorbidities. This approach should be incorporated into routine practice to ensure optimal treatment of gout in CKD. More research is required to investigate whether treatment of asymptomatic hyperuricemia has clinical benefits.

Targets and mechanisms of dietary anthocyanins to combat hyperglycemia and hyperuricemia: a comprehensive review

Hyperglycemia and hyperuricemia are both metabolic disorders related to excessive amount of metabolites in blood, which are considered as high risk factors for the development of many chronic diseases. Enzymes, cells, tissues and organs, which are relevant to metabolism and excretion of glucose and UA, are usually regarded to be the targets in treatment of hyperglycemia and hyperuricemia. Several drugs have been commonly applied to combat hyperglycemia and hyperuricemia through various targets but with unignorable side effects. Anthocyanins have become promising alternatives against hyperglycemia and hyperuricemia because of their bio-activities with little side effects. Structurally different anthocyanins from berry fruits, cherries and purple sweet potato lead to the diverse functional activity and property. This review is aimed to illustrate the specific targets that are available for anthocyanins from berry fruits, cherries and purple sweet potato in hyperglycemia and hyperuricemia management, as well as discuss the structure-activity relationship, and the underlying mechanisms associated with intracellular signaling pathway, anti-oxidative stress and anti-inflammation. In addition, the relationship of hyperglycemia and hyperuricemia, and the possibly regulative role of anthocyanins against them, along with the effects of anthocyanins in clinical trial are mentioned.