Epigallocatechin gallate reduces uric acid levels by regulating xanthine oxidase activity and uric acid excretion in vitro and in vivo

Abstract

Background: This study investigates the effect of epigallocatechin gallate (EGCG) from tea leaves on hyperuricemia and explores the underlying mechanisms in vitro and in vivo.Methods: The effects of EGCG on proliferation of BRL 3A rat liver cells were evaluated by CCK8 and after stimulation by xanthine the uric acid and xanthine oxidase (XOD) levels were evaluated by a kit; In an in vivo experiment, rats were treated with oxonic acid potassium salt combined with ethylamine pyrimidine to induce high uric acid hematic disease (7 days), The serum uric acid levels and XOD levels were evaluated by a kit, The expressions of OTA1 and GLUT9 were detected by RT-qPCR and Immunohistochemical.Results: EGCG had no effect on proliferation, and significantly reduced serum uric acid levels and inhibited XOD activity (P<0.05). The rat model exhibited a significant rise in blood uric acid levels (54.59 mg/dL), and EGCG significantly reduced the high level of serum uric acid and inhibited XOD activity in the serum and liver tissues (P<0.05). RT-PCR showed that EGCG significantly increased mOAT1 expression in the kidney tissues and reduced mGLUT9 expression (P<0.05). Immunohistochemical results showed that EGCG significantly increased OAT1 expression in the kidney tissues and decreased GLUT9 expression (P<0.05).Conclusions: These results demonstrate that EGCG has obvious anti-hyperuricemia effects in vitro and in vivo via the inhibition of XOD activity and GLUT9 expression and the promotion of OAT1 expression.

Effect of Decaffeinated Green Tea Polyphenols on Body Fat and Precocious Puberty in Obese Girls: A Randomized Controlled Trial

“…Also, this study reported that DGTP could reduce the concentration of uric acid in children, and in the adjusted model, the significant effect still existed. Some in vitro and in vivo studies ( 41 , 42 ) showed that GTP might have the effect of lowering uric acid through decreasing uric acid production and increasing uric acid excretion via the inhibition of xanthine oxidase activity and glucose transporter-9 expression and the promotion of organic anion transporter-1 expression.…”

Acute effect of green tea catechins on uric acid metabolism after alcohol ingestion in Japanese men

“…Previously, green tea polyphenols dose-dependently decreased XO activity in the liver of the hyperuricemic mice. (13)(14)(15) It was also reported that the consumption of green tea inhibited the increase in plasma XO activity induced by exercise in weight-trained men. (23) In this study, U-Xa/Hx excretions were signi cantly higher in the SC group than in the SW group, indicating that the increase in U-Xa/Hx excretion in the SC group might be due to the effect of green tea catechins on XO activity, although we could not measure XO activity directly.…”

“…It has been reported that green tea polyphenols decrease serum UA concentrations by regulating XO activity and urinary excretion of UA in hyperuricemic mice. (13)(14)(15) In addition, green tea extract lowers serum UA concentrations in healthy individuals to some extent. (16) These studies together indicate a role for green tea catechins in UA metabolism.…”

Research Advances in the Mechanisms of Hyperuricemia‐Induced Renal Injury

“…significantly reduced the renal expression of URAT1 and increased that of OAT1, thereby lowering the serum UA level and improving renal injury [ 147 ]. Epigallocatechin gallate exerted hypouricemic effects by suppressing XO activity and GLUT9 expression and promoting OAT1 expression in vivo and in vitro [ 148 ]. Tu-Teng-Cao extract remarkably decreased the concentration of serum UA in potassium oxonate-induced hyperuricemia rats [ 149 ].…”