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Studies have shown that targeting xanthine oxidase (XO) can be a feasible treatment for fructose-induced hyperuricemia and hyperglycemia. This study aimed to evaluate the dual regulatory effects and molecular mechanisms of diacylated anthocyanins from purple sweet potato (diacylated AF-PSPs) on hyperglycemia and hyperuricemia induced by a high-fructose/high-fat diet. The body weight, organ index, serum biochemical indexes, and liver antioxidant indexes of mice were measured, and the kidneys were observed in pathological sections. The relative expression levels of messenger RNAs (mRNAs) of fructose metabolism pathway enzymes in kidney were detected by fluorescent real-time quantitative polymerase chain (qPCR) reaction technique, and the expression of renal transporter protein and inflammatory factor pathway protein was determined by immunohistochemistry (IHC) technique. Results showed that diacylated AF-PSPs alleviated hyperuricemia in mice, and that this effect might be related to the regulation of liver XO activity, lipid accumulation, and relevant renal transporters. Diacylated AF-PSPs reduced body weight and relieved lipid metabolism disorder, liver lipid accumulation, and liver oxidative stress, thereby enhancing insulin utilization and sensitivity, lowering blood sugar, and reducing hyperglycemia in mice. Also, diacylated AF-PSPs restored mRNA levels related to renal fructose metabolism, and reduced kidney injury and inflammation. This study provided experimental evidence for the mechanisms of dual regulation of blood glucose and uric acid (UA) by diacylated AF-PSPs and their utilization as functional foods in the management of metabolic syndrome.

Objective: To investigate the effects of electrolytic drinking water on the hyperuricemia and the potential mechanism., Methods: The 6-week-old SD rats were induced as the animal model with hyperuricemia by yeast extract(10 g/kg) and adenine(100 g/kg) gavage(twice per day) combined with oxygen oxazine acid potassium(300 mg/kg, the 1~(st), 5~(th) and 10~(th )day) i. p. Then the rats were supplied electrolytic drinking water in different dosages(1 mL, 2 mL and 3 mL) by gavage for 7 days. Weight was measured at regular intervals. The 24-hour urine was sampled by metabolic cage for the measurements of uric acid, creatinine and urea nitrogen levels. The parameters for the uric acid clearance were calculated. The serum was sampled after execution for the determination of serum uric acid, creatinine. The activities of xanthine oxidase and adenine dehydrogenase were detected. The morphological measurements of stomach and kidney were completed., Results: The hyperuricemia model was successfully induced by this method. In the intervention, the pH of urine was significantly elevated along with the electrolytic drinking water intake(P<0. 01). The excretion of uric acid in the rats with hyperuricemia was significantly increased while administrated with electrolytic drinking water. The effects of improving uric acid excretion were enhanced along with the intake of electrolytic drinking water. The levels of serum uric acid(group Model, Model+Treatment 1, Model+Treatment 2 and Model+Treatment 3: 693. 7 μmol/L, 668. 1 μmol/L, 642. 5 μmol/L, 633. 1 μmol/L), urine uric acid(5740. 0 μmol/L, 5894. 1 μmol/L, 5562. 3 μmol/L, 5083. 2 μmol/L) and urea nitrogen(11. 40 mmol/L, 10. 47 mmol/L, 9. 54 mmol/L, 8. 93 mmol/L) were significantly decreased in the model rats with high dose intervention(P<0. 05). Clearance of uric acid was obviously increased(9. 27%, 10. 40%, 10. 44%, 11. 13%, P<0. 05). However, no pathological change was observed among the three groups with intervention., Conclusion: The electrolytic drinking water intake is benefit for the excretion of uric acid of hyperuricemia rat. Enhancing alkalization of urine is considered as the important mechanism of the beneficial effects.

Objective: To explore an effective method for inducing a rat model with hyperuricemia in a short period and assess the effects of the model. Methods: Sprague-Dawley rats were adopted as donors and randomly divided into control group (CT group, n=6) and 5 model groups (M1-M5 groups, n=8 in each group). M1 group (gavage with 10 g/kg yeast extracts and 100 mg/kg adenine, twice per day, 300 mg/kg oxonic acid potassium by intraperitoneal injection, in the 7 th day of model inducing), M2 group (gavage with 10 g/kg yeast extracts and 100 mg/kg adenine, twice per day, 300 mg/kg oxonic acid potassium by intraperitoneal injection, in the 1 st , 3 rd and 7 th day of model inducing),M3 group (gavage with 10 g/kg yeast extracts and 100 mg/kg adenine, twice per day, 300 mg/kg oxonic acid potassium by intraperitoneal injection, once per day during the model inducing), M4 group (gavage with 20 g/kg yeast extracts and 100 mg/kg adenine, twice per day, 300 mg/kg oxonic acid potassium by intraperitoneal injection, once per day during the model inducing), M5 group (gavage with 30 g/kg yeast extracts and 100 mg/kg adenine, twice per day, 300 mg/kg oxonic acid potassium by intraperitoneal injection, once per day during the model inducing), and group CT (gavaged with equal volume sterilized water and intraperitoneal injected with normal saline according to the weight and at the same frequency as the model groups). The model inducing lasted for 7 days. After the inducing was finished, blood and 24-hour urine were sampled for uric acid and creatinine determination. Then rats were maintained for 2 weeks and blood and 24-hour urine samples were collected, the concentration of uric acid and creatinine were detected. The kidney and stomach were weighed,morphological changes in kidney were observed. Results: After model inducing, the body weight of rats in all model groups was lower than that of the control group (P＜0.01). Deaths occurred in all the rats with model treatments except M2. M4 and M5 groups were failed to be analyzed because of the high mortality, model 1 and 3 groups had 4 and 2 deaths, respectively. The uric acid levels in blood and urine of the model groups were significantly elevated (P＜ 0.01) at the end of model inducing. The model 2 group's blood uric acid was highest among the model groups (P＜0.05). It sustained a higher concentration than CT group in the three model groups after 2 weeks feeding (P＜0.05). The kidneys in model groups obviously swelling and were heavier than CT group (P＜0.01). The inflammation and structural damages were observed in kidneys of all model groups. Conclusion: The yeast extract (10 g/kg), adenine (100 mg/kg) gavage combined with intraperitoneal injections(the 1 st , 3 rd , 7 th day during inducing) of potassium oxonate can be an rapid and effective method for inducing the rat model with hyperuricemia, which can be suggested to the related research.

Objective: To investigate the effect of ethanol extracts from Dioscoreae Nipponicae Rhizoma on hyperuricemic mice., Methods: The hyperuricemia was induced by gavage of hypoxanthine and subcutaneous injection of potassium oxonate (model A) or subcutaneous injection of uric acid (model B) in ICR male mice. The mice in ethanol extracts groups were administrated with Dioscoreae Nipponicae Rhizoma ethanol extracts 5.4 g/kg by gavage, the positive control groups were given with 10 mg/ml allopurinol or 5 mg/ml benzbromarone by gavage, respectively. The plasma uric acid levels were measured by using HPLC., Results: The plasma uric acid levels of model group, control group and ethanol extract group in model A mice were (40.03±27.24), (4.08±1.47) and (18.10±8.87) g/mL (compared with model group, P <0.05), respectively. The plasma uric acid levels of model group, control group and ethanol extract group in model B mice were (18.57±3.83), (4.29±2.36) and (15.36±2.71) g/mL (compared with model group, P <0.05), respectively., Conclusion: The ethanol extracts from Dioscoreae Nipponicae Rhizoma have certain hypouricemic effect in hyperuricemic mice induced by hypoxanthine and potassium oxonate or by uric acid.

Objective: To study the preventive and therapeutic effects of Quercetin (Que) on hyperuricemia and renal failure in rats., Methods: Seventy rats were divided into ten groups, normal control group, model control group, allopurinol group and seven Que groups (50, 40, 30, 20, 10, 5 and 2.5 mg/kg). Hyperuricemia and renal failure in rats were induced by adenine and ethambutol hydrochloride intragastrically, and then Que was given for 3 weeks. The items related to high serum uric acid and renal injury were observed., Results: Levels of serum uric acid (SUA), serum urea nitrogen ( SUN), serum creatinine (SCr), malonaldehyde (MDA) and the activity of xanthine oxidase (XOD) in liver were lowered effectively by Que, and the activity of superoxide dismutase (SOD) in serum was increased. The better results of lowering serum uric acid and protecting against renal failure were at the dosage of Que between 10 and 20 mg/kg., Conclusion: Hyperuricemia and renal failure in rats could be intervened by Que. The possible mechanism might be inhibiting the activity of liver XOD and improving the ability of clearing oxygen free radicals and reducing lipid peroxidation, which might play an important role in reducing serum uric acid level and protecting kidney.

The effects of mangiferin on uric acid excretion, kidney function and related renal transporters were investigated in hyperuricemic mice induced by potassium oxonate. Mice were divided into normal control group, and 5 hyperuricemic groups with model control, 50, 100, and 200 mg x kg(-1) mangiferin, and 5 mg x kg(-1) allopurinol. Mice were administered by gavage once daily with 250 mg x kg(-1) potassium oxonate for seven consecutive days to create the model. And 3 doses of mangiferin were orally initiated on the day 1 h after potassium oxonate was given, separately. Serum uric acid, creatinine and urea nitrogon levels, as well as urinary uric acid creatinine levels were measured. Mouse uromodulin (mUMOD) levels in serum, urine and kidney were determined by ELISA method. The mRNA and protein levels of related renal transporters were assayed by RT-PCR and Western blotting methods, respectively. Compared to model group, mangiferin significantly reduced serum uric acid, creatinine and urea nitrogon levels, increased 24 h uric acid and creatinine excretion, and fractional excretion of uric acid in hyperuricemic mice, exhibiting uric acid excretion enhancement and kidney function improvement. Mangiferin was found to down-regulate mRNA and protein levels of urate transporter 1 (mURAT1) and glucose transporter 9 (mGLUT9), as well as up-regulate organic anion transporter 1 (mOAT1) in the kidney of hyperuricemic mice. These findings suggested that mangiferin might enhance uric acid excretion and in turn reduce serum uric acid level through the decrease of uric acid reabsorption and the increase of uric acid secretion in hyperuricemic mice. Moreover, mangiferin remarkably up-regulated expression levels of renal organic cation and carnitine transporters (mOCT1, mOCT2, mOCTN1 and mOCTN2), increased urine mUMOD levels, as well as decreased serum and kidney mUMOD levels in hyperuricemic mice, which might be involved in mangiferin-mediated renal protective action.