Study On The Effect And Mechanism Of Mesalazine And Arginine Co-amorphous Substance On Reducing Uric Acid

Hyperuricemia is a chronic metabolic disease,its pathogenesis is related to abnormal purine metabolism or uric acid excretion disorders,mainly divided into primary and secondary,has become the fourth highest after hyperlipidemia,hyperglycemia and hypertension.In our country,the prevalence of high uricemia is increasing year by year and presents a trend of young people.The treatment of hyperuricemia is mainly divided into drug therapy and non-drug therapy.The non-drug therapy is mainly to control diet and exercise,but the effect of reducing uric acid is limited.Drug therapy can be divided into four categories according to the treatment mechanism,namely xanthine oxidase inhibitors,uricotropic drugs,recombinant uricase drugs and anti-inflammatory drugs,but all of them have a variety of adverse reactions,such as liver and kidney injury, gastrointestinal discomfort,and are expensive and not suitable for long-term use.Therefore,it is of great significance to find a new drug to reduce uric acid.Mesalazine is a commonly used drug in the treatment of ulcerative colitis,which has anti-inflammatory,antioxidant and antibacterial effects.Studies have shown that mesalazine derivative olsalazine sodium has the effect of lowering uric acid.Clinical investigations have shown that mesalazine can reduce the level of uric acid in patients with colitis,but due to low solubility and permeability of mesalazine,oral bioavailability is poor.Therefore,the purpose of this study was to improve oral bioavailability of mesalazine by crystal modification technology,and to study the uric acid lowering effect and mechanism of the dominant crystal of mesalazine.Objective:1.According to the guiding principles of Chinese Pharmacopoeia（2020edition）,to establish the quality standard and HPLC detection method of mesalazine;2.To study the blood concentration and tissue distribution of mesalazine and arginine coamorphous;3.To study the efficacy and mechanism of methalazine and arginine co-amorphous substance to reduce uric acid.Methods:1.Based on"Chinese Pharmacopoeia"2020 edition,the physical and chemical properties of mesalazine were determined,the liquid chromatography methodology was investigated,and the quality standard of mesalazine and the HPLC method were established.2.Healthy rats were given 30 mg/kg mesalazine and arginine coamorphous and mesalazine bulk drug by intragastric administration to detect the content of mesalazine in rat plasma and tissue,and to study the blood concentration and tissue distribution of mesalazine and arginine coamorphous substance in rats.3.SD rats were given 100 mg/kg potassium oxazine and 500 mg/kg hypoxanthine and 200 mg/kg adenine and 250 mg/kg ethambutol for 14 days,respectively,to prepare two different rat models of hyperuricemia.Mesalazine and arginine coamorphous 30 mg/kg,100 mg/kg,300 mg/kg and benbromarone 20 mg/kg were given intragastric administration for 7 consecutive days.The serum UA,BUN and CRE levels of rats were detected to evaluate the effect of mesalazine and arginine coamorphous on renal function of rats.The levels of ALT,AST,ALB and LDH in serum of rats were detected to evaluate the effect of mesalazine and arginine coamorphous on rat liver function.CHO,TG,HDL and LDL levels in serum of rats were detected,and the effects of mesalazine and arginine coamorphous on blood glucose and lipid of rats were evaluated.The SOD,T-AOC and MDA levels in serum of rats were detected to study the effect of mesalazine and arginine coamorphous on the oxidation level of rats.The effect of Mesala on pathological morphology of rat liver and kidney tissue was investigated by liver and kidney index and HE staining.ADA and XOD levels in serum of rats were determined,as well as the protein expression levels of ion transporters OAT1 and URAT1 in kidney and ileum of rats were determined by western blot to investigate the mechanism of uric acid reduction of mesalazine and arginine coamorphous.Serum metabolomics was studied in rats to search for differential metabolites and pathways.Results:1.The maximum concentration of mesalazine and arginine coamorphous was 7.39μg/mL at 0.5 h,and the area under the curve was 209.9μg·h·mL^-1,and the maximum concentration of mesalazine bulk was 5.35μg/mL at 0.5 h,and the area under the curve was 160.6μg·h·mL^-1.2.The levels of UA,BUN,CRE,ALT,ALB,CHO,SOD,T-AOC,ADA and XOD of rats were significantly increased by potassium oxazine combined with hypoxanthine.After 7 days of treatment,compared with the model group,The levels of UA,CRE,ALT,ALB,CHO,SOD,T-AOC,ADA and XOD were significantly decreased by mesalazine and arginine coamorphous as well as phenylbromarone.Pathological sections showed that the rat renal tubular epithelial cells were degenerated and the cytoplasm was loose after modeling.There was mild steatosis and microvesicles in the cytoplasm of hepatocytes.After the administration of mesalazine and arginine coamorphous and the positive drug benzbromarone,the renal cells vacuolated significantly,and the liver cells became round and full.OAT1 protein expression in kidney and ileum was significantly decreased in the model group,and URAT1 protein expression was significantly increased.After treatment,there was a significant increase in OAT1 protein expression and a significant decrease in URAT1protein expression.Metabolomics showed that hyperuricemia rats may be related to a variety of amino acid metabolic pathways.3.The levels of UA,CRE,BUN,CHO,HDL,LDL,ADA,T-AOC and MDA were significantly increased by adenine combined with ebutol.After treatment,compared with the model group,the levels of UA,CRE,BUN,ADA and T-AOC were significantly decreased by mesalazine and arg coamorphous,and by phenylbromarone.Conclusions:The dominant co-amorphous substance of mesalazine and arginine can significantly improve the bioavailability of mesalazine,which has a certain effect on the oxidation level of the liver,kidney and body of HUA rats,and reduces the uric acid level of HUA rats by inhibiting XOD and ADA two kinds of uric acid synthetase,and downregulating the expression of uric acid transporter URAT1 and upregulating OAT1protein.The two HUA rat models are efficient and stable,and in the future,more experimental animal models corresponding to clinical patients will be evaluated and studied in the mechanism,and at the same time try to study whether mesalazine has a positive effect on gout disease,which is of great significance for finding new indications for mesalazine.