Possible Interaction: Citrulline and Glutamine

“Although there is no strong evidence to support that glutamine is a major precursor for citrulline synthesis in humans, glutamine has the potential to increase overall gut function and in this way increase citrulline production.”

“Purpose of reviewThis article analyzes the contribution of glutamine to the synthesis of citrulline and reviews the evidence that glutamine supplementation increases citrulline production.”

“Within this context, defining the contribution of glutamine to the production of citrulline , and thus to de-novo arginine synthesis, has become a pressing issue.”

“In addition, several studies in animals and humans confirmed the important precursor relationship between glutamine, citrulline, and arginine by showing that plasma levels of citrulline and arginine increased after provision of glutamine (6, 8, 11, 12, 22, 23, 25, 26, 35) (Fig. 2).”

“ L-Glutamine (0.5 and 1 mM), but not 0.5 mM L-arginine, L-alanine, L-glutamate, or L-lysine, inhibited L-citrulline transport by EC.”

“ L-Glutamine (0.5mM) decreased L-arginine synthesis from L-citrulline , whereas 0.5 mM L-arginine, L-alanine, L-glutamate, or L-lysine had no effect.”

“The inhibition of L-citrulline transport by L-glutamine was dose dependent and competitive in nature.”

“This study shows that an intravenous supplement of glutamine increases the production of citrulline and arginine and compensates for the inhibitory effect of ischemia-reperfusion injury.”

“Because sepsis can affect gut function and integrity, alterations in glutamine metabolism may exist and lead to decreased citrulline production.”

“Positive correlations were found between glutamine uptake and the production of citrulline (r=0.814, P=0.0013) and glycine (r=0.734, P=0.0080).”

“In both groups, ingestion of glutamine but not of glutamate increased the plasma concentrations of citrulline and arginine, substrates produced in the intestine and the liver.”

“The change in plasma arginine, citrulline , and urea concentrations was significantly (P < 0.01) higher after glutamine ingestion than after water or glutamate ingestion.”

“ Glutamine contributed up to 25% ± 2% of the rate of appearance of citrulline.”

“In conclusion, oral citrulline may have more benefits than arginine and glutamine in mitigating intestinal ischemia and reperfusion-induced adverse effects.”

“ Glutamine significantly increased the urine levels of acetamide, acetate, citrulline , creatinine, and methymalonate, and decreased the urine levels of ethanol and formate (p < 0.05).”