Crf 1 diet

The animal study was conducted at Tsukuba Research Institute, BoZo Research Center Inc., Japan. Seven‐week‐old male ZDF rats (ZDF/Crl‐Lepr^fa; fa/fa) were purchased from Charles River Laboratories Japan (Yokohama, Japan) and fed a CRF‐1 diet (Oriental Yeast, Tokyo, Japan). All rats were maintained on a 12‐h light‐dark cycle and given free access to food and water except during the period of caloric restriction for the pair‐feeding group. This study was approved by the Institutional Animal Care and Use Committee of Tsukuba Research Institute, BoZo Research Center Inc., and was performed according to the institutional guidelines on the management and welfare of laboratory animals.

We prepared a CRF-1 diet (Oriental Yeast Co., Ltd., Tokyo, Japan) as a control diet (CD) and four types of KDs: (1) a normal KD without addition of any amino acid (normal KD), (2) a KD with a 3.3% CaseinAA mixture (KD + CA), (3) a KD with a 3.3% AminoL40 mixture (KD + 3.3% AL), and (4) a KD with a 2.5% AminoL40 mixture (KD + 2.5% AL). The compositions of these diets are shown in Supplementary Table S1. The KR was calculated using Woodyatt’s formula (Woodyatt, 1921 (link)), which considers the ketogenic macronutrients represented by portions of protein and fat versus glucogenic macronutrients instead of calculating the simple KR using fat: (protein + carbohydrate). Woodyatt’s KR of all types of KD was maintained between 4.8:1 and 5.3:1 (Supplementary Table S1). To evaluate the effect of AminoL40 alone, a non-ketogenic diet based on AIN-93G was prepared with a 3.3% AminoL40 mixture (CD + 3.3% AL). The proportions of each amino acid in the CaseinAA and AminoL40 mixture are shown in Supplementary Table S2.