Possible Interaction: Arginine and Creatine

“ Creatine synthesis consumes some 20–30% of arginine ’s amidino groups, whether provided in the diet or synthesized within the body.”

“AI is also expressed in various extrahepatic tissues and may play a role in regulating arginine levels and in providing ornithine for biosynthetic reactions that generate various critical intermediary metabolites such as glutamate, glutamine, GABA, agmatine, polyamines, creatine , proline, and nitric oxide.”

“However, until now the effects of Arg and/or Gly supplementation on Cr brain levels and behaviour have been controversial.”

“ Creatine synthesis makes major demands on the metabolism of glycine, arginine , and methionine.”

“Because high cerebral guanidinoacetate might be toxic, lowering the arginine supplementation with additional creatine supplementation might be important.”

“GAA or creatine supplementation reduced arginine conversion to creatine by 46% and 43%, respectively (P < 0.01), but did not spare amino acids for whole-body protein synthesis, suggesting that limited amino acids were diverted to protein at the expense of creatine synthesis.”

“ Arginine supplementation significantly increased the urine levels of 4-aminohippurate, acetate, creatine , creatinine, ethanolamine, formate, hippurate, homogentisate, indoxyl sulfate, and phenylacetyglycine.”

“Discussion and conclusion: Overall, these results demonstrated that a single administration of creatine improves working memory efficiency, and, when co-administrated with l-arginine , improves reference memory retention, a phenomenon that is possibly associated with increased creatine/phosphocreatine levels and l-arginine-derived NO synthesis.”

“ Creatine supplementation significantly decreased the renal activity of l-arginine :glycine amidinotransferase and plasma guanidinoacetate and prevented the decrease in hepatic SAM concentration in rats fed the HF diet.”