{"title":"Effects of d-alanine Intake on Amino Acid Metabolism and Kidney Function in Healthy Adults: A Multicenter, Randomized Pilot Study","authors":"Megumi Oshima , Tadashi Toyama , Tatsuhiko Toyama , Yusuke Nakade , Toshiaki Tokumaru , Keisuke Sako , Sho Kajikawa , Daiki Hayashi , Hajime Sanada , Takahiro Yuasa , Akihiko Koshino , Keisuke Horikoshi , Taichiro Minami , Shunsuke Tsuge , Akira Tamai , Shiori Nakagawa , Ryo Nishioka , Takeshi Zoshima , Kiyoaki Ito , Shinji Kitajima , Takashi Wada","doi":"10.1016/j.cdnut.2024.103787","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><p><span>d</span>-alanine administration prevented kidney damage in a murine acute kidney injury model. Further data are needed on the influence of <span>d</span>-alanine on kidney function in humans.</p></div><div><h3>Objective</h3><p>This study investigated the effects of <span>d</span>-alanine intake on amino acid metabolism and kidney function in healthy volunteers.</p></div><div><h3>Methods</h3><p>This multicenter pilot study randomly assigned individuals from the general Japanese population to receive 3 g or 6 g of <span>d</span>-alanine intake per day for 7 d in a 1:1 ratio. The primary endpoint was the mean change in plasma and urine <span>d</span>-alanine levels from baseline to 7 d after intake. The secondary endpoints were mean changes in kidney function and other clinical factors. Safety was assessed by evaluating adverse events and clinical parameters.</p></div><div><h3>Results</h3><p>We randomly assigned 24 participants to the 3-g (<em>n</em> = 12) and 6-g <span>d</span>-alanine (<em>n</em> = 12) groups. The mean baseline estimated glomerular filtration rate (eGFR) was 73 mL/min/1.73 m<sup>2</sup>. The mean plasma <span>d</span>-alanine concentration increased from baseline by 77.5 ± 34.3 and 192.1 ± 80.9 nmol/mL in the 3-g and 6-g <span>d</span>-alanine groups (both p < 0.0001), respectively, in a dose-dependent manner (between-group difference: 114.6 nmol/mL; 95% CI: 62.1–167.2; <em>P</em> = 0.0002). A similar increase was observed for the urine <span>d</span>-alanine to creatinine ratio. The mean eGFR was elevated by 5.7 ± 8.8 mL/min/1.73 m<sup>2</sup> in the 6-g <span>d</span>-alanine group (<em>P</em> = 0.045) but did not significantly change in the 3-g <span>d</span>-alanine group. Nonserious adverse events were reported in 11 participants.</p></div><div><h3>Conclusions</h3><p><span>d</span>-alanine intake increased plasma and urine <span>d</span>-alanine levels and was well tolerated in participants with normal kidney function. These results will be useful in future trials investigating the effects of <span>d</span>-alanine intake on kidney disease progression in patients with chronic kidney disease.</p><p>This trial was registered at the UMIN Clinical Trials Registry as UMIN000051466.</p></div>","PeriodicalId":10756,"journal":{"name":"Current Developments in Nutrition","volume":"8 7","pages":"Article 103787"},"PeriodicalIF":3.8000,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2475299124017219/pdfft?md5=10de7c5cd41bec56317f9b7ab2f683c7&pid=1-s2.0-S2475299124017219-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Current Developments in Nutrition","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2475299124017219","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"NUTRITION & DIETETICS","Score":null,"Total":0}
引用次数: 0
Abstract
Background
d-alanine administration prevented kidney damage in a murine acute kidney injury model. Further data are needed on the influence of d-alanine on kidney function in humans.
Objective
This study investigated the effects of d-alanine intake on amino acid metabolism and kidney function in healthy volunteers.
Methods
This multicenter pilot study randomly assigned individuals from the general Japanese population to receive 3 g or 6 g of d-alanine intake per day for 7 d in a 1:1 ratio. The primary endpoint was the mean change in plasma and urine d-alanine levels from baseline to 7 d after intake. The secondary endpoints were mean changes in kidney function and other clinical factors. Safety was assessed by evaluating adverse events and clinical parameters.
Results
We randomly assigned 24 participants to the 3-g (n = 12) and 6-g d-alanine (n = 12) groups. The mean baseline estimated glomerular filtration rate (eGFR) was 73 mL/min/1.73 m2. The mean plasma d-alanine concentration increased from baseline by 77.5 ± 34.3 and 192.1 ± 80.9 nmol/mL in the 3-g and 6-g d-alanine groups (both p < 0.0001), respectively, in a dose-dependent manner (between-group difference: 114.6 nmol/mL; 95% CI: 62.1–167.2; P = 0.0002). A similar increase was observed for the urine d-alanine to creatinine ratio. The mean eGFR was elevated by 5.7 ± 8.8 mL/min/1.73 m2 in the 6-g d-alanine group (P = 0.045) but did not significantly change in the 3-g d-alanine group. Nonserious adverse events were reported in 11 participants.
Conclusions
d-alanine intake increased plasma and urine d-alanine levels and was well tolerated in participants with normal kidney function. These results will be useful in future trials investigating the effects of d-alanine intake on kidney disease progression in patients with chronic kidney disease.
This trial was registered at the UMIN Clinical Trials Registry as UMIN000051466.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
