薬理と治療

Abstract

Background　Yerba mate(Ilex paraguariensis A. St. Hill.)is native to South America. The leaves of this plant have long been consumed as a drink by locals; this drink is considered one of the three most popular beverages in the world. According to previous animal studies, yerba mate leaf extract(hereafter referred to as MATESOLTM)inhibits lipogenesis, promotes lipolysis, and reduces cholesterol levels. However, only few human studies have reported these effects. Objectives　This study was conducted to assess the efficacy of MATESOLTM in reducing abdominal fat in healthy adults with a relatively high BMI(23.0≤BMI<30.0). Methods　This randomized, double–blind, placebo–controlled parallel–group comparison study comprised 44 healthy Japanese subjects(23.0≤BMI<30.0). The subjects were randomly allocated to either the placebo or test food group(22 per group)to receive the respective intervention for 12 weeks. The primary outcome was the degree of change in abdominal visceral fat area. Moreover, abdominal subcutaneous fat area, abdominal total fat area, low–density lipoprotein(LDL)cholesterol, high–density lipoprotein(HDL)cholesterol, LDL–cholesterol to HDL–cholesterol(L/H)ratio, triglycerides, body weight, BMI, body fat percentage, waist circumference, hip circumference, waist to hip(W/H)ratio, ankle circumference, thigh circumference, triceps subcutaneous fat thickness, subscapular subcutaneous fat thickness, fasting blood glucose, HbA1c(NGSP), resting energy expenditure, and questionnaire were also assessed. Results　Forty–four subjects completed the trial, 22 in the test food group and 22 in the placebo group. No significant reduction in abdominal fat area was found in the test food group compared to the placebo group. In a subgroup analysis excluding five subjects who recorded lifestyle changes in their daily diary during the ingestion period, the degree of change in abdominal visceral fat area and abdominal total fat area at week 12 were found to be significantly lower in the test food group than in the placebo group. Furthermore, by determining the effect of the test food on lipid profiles in a subgroup of subjects with LDL cholesterol levels between 120 and 159 mg/dL, the measured value of L/H ratio at week 12 was found to be significantly lower in the test food group than in the placebo group. No medically problematic changes occurred with the ingestion of MATESOLTM. Conclusions　MATESOLTM reduced the abdominal visceral fat area in healthy subjects with a relatively higher BMI and appeared to be safe under the conditions employed in the present study.Trial Registration　UMIN–CTR: UMIN000051265 Funding　Tokiwa Phytochemical Co., Ltd.(Jpn Pharmacol Ther 2024;52:1067‒76)