Yuka Kawakami1, Arisa Yasuda2, Motoki Hayashi2, Misuzu Akiyama2, Toshihiko Asai3, Toshio Hosaka4, Hidekazu Arai2. 1. Laboratory of Clinical Nutrition and Management, Graduate Division of Nutritional and Environmental Sciences, and Graduate School of Integrated Pharmaceutical and Nutritional Sciences, The University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan. kawakami@u-shizuoka-ken.ac.jp. 2. Laboratory of Clinical Nutrition and Management, Graduate Division of Nutritional and Environmental Sciences, and Graduate School of Integrated Pharmaceutical and Nutritional Sciences, The University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan. 3. Asai Clinic, Shizuoka, Japan. 4. Laboratory of Clinical Nutrition, Graduate Division of Nutritional and Environmental Sciences, and Graduate School of Integrated Pharmaceutical and Nutritional Sciences, The University of Shizuoka, Shizuoka, Japan.
Abstract
INTRODUCTION/ OBJECTIVES: Alcohol consumption is associated with hyperuricemia and gout. Previous studies have indicated a role for green tea catechins in uric acid (UA) metabolism. This study aimed to elucidate the acute effect of green tea catechins in terms of enhancing urinary excretion of UA and xanthine/hypoxanthine (Xa/HX; UA precursors) after alcohol ingestion. METHODS: In a randomized crossover study, ten healthy Japanese subjects consumed test meals, including a Japanese distilled spirit (Shōchū) with water (SW) or Shōchū with catechin-rich green tea (SC), each containing 20 g of alcohol. The SC contained 617 mg of catechin in total. Serum and urine UA andXa/HX concentrations were measured. Blood samples were collected after 2.5 h, and urine samples were collected between 0 and 5 h after consuming the test meal. RESULTS: Urine UA and Xa/HX excretions were significantly higher in the SC group than in the SW group (UA: SW, 0.45 ± 0.08; SC, 0.52 ± 0.09; Xa/HX: SW, 0.08 ± 0.04; SC, 0.16 ± 0.05 mg/kg/h). UA clearance (CUA) and fractional UA excretion (FEUA) tended to increase more in the SC group than in the SW group (CUA: SW, 7.76 ± 2.14; SC, 8.75 ± 2.23 mL/min/1.73 m2; FEUA: SW, 6.08 ± 1.36; SC, 6.64 ± 1.42%). No significant differences in serum UA andXa/HX concentrations were observed between two groups. CONCLUSIONS: It was concluded that green tea catechins can enhance the excretion of UA and Xa/HX, even though alcohol is ingested. TRIAL REGISTRATION NUMBER: UMIN000040076. Retrospectively registered 7 April 2020. https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000045687 Key Points • Green tea catechins enhance the excretion of uric acid and xanthine/hypoxanthine, even when alcohol is ingested simultaneously. • In case of non-adherence of limiting alcohol intake, catechin-rich green tea may be an effective dietary component to continue dietary therapy.
RCT Entities:
INTRODUCTION/ OBJECTIVES:Alcohol consumption is associated with hyperuricemia and gout. Previous studies have indicated a role for green tea catechins in uric acid (UA) metabolism. This study aimed to elucidate the acute effect of green tea catechins in terms of enhancing urinary excretion of UA and xanthine/hypoxanthine (Xa/HX; UA precursors) after alcohol ingestion. METHODS: In a randomized crossover study, ten healthy Japanese subjects consumed test meals, including a Japanese distilled spirit (Shōchū) with water (SW) or Shōchū with catechin-rich green tea (SC), each containing 20 g of alcohol. The SC contained 617 mg of catechin in total. Serum and urine UA and Xa/HX concentrations were measured. Blood samples were collected after 2.5 h, and urine samples were collected between 0 and 5 h after consuming the test meal. RESULTS: Urine UA and Xa/HX excretions were significantly higher in the SC group than in the SW group (UA: SW, 0.45 ± 0.08; SC, 0.52 ± 0.09; Xa/HX: SW, 0.08 ± 0.04; SC, 0.16 ± 0.05 mg/kg/h). UA clearance (CUA) and fractional UA excretion (FEUA) tended to increase more in the SC group than in the SW group (CUA: SW, 7.76 ± 2.14; SC, 8.75 ± 2.23 mL/min/1.73 m2; FEUA: SW, 6.08 ± 1.36; SC, 6.64 ± 1.42%). No significant differences in serum UA and Xa/HX concentrations were observed between two groups. CONCLUSIONS: It was concluded that green tea catechins can enhance the excretion of UA and Xa/HX, even though alcohol is ingested. TRIAL REGISTRATION NUMBER: UMIN000040076. Retrospectively registered 7 April 2020. https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000045687 Key Points • Green tea catechins enhance the excretion of uric acid and xanthine/hypoxanthine, even when alcohol is ingested simultaneously. • In case of non-adherence of limiting alcohol intake, catechin-rich green tea may be an effective dietary component to continue dietary therapy.
Entities:
Keywords:
Alcohol ingestion; Green tea catechins; Hyperuricemia; Hypoxanthine; Xanthine