Glutamine in vitro supplementation partly reverses impaired macrophage function resulting from early weaning in mice.
OBJECTIVE
Glutamine is one of the most abundant amino acids found in maternal milk, and its concentration increases throughout lactation. Because glutamine is essential for macrophage functionality, it is hereby suggested that early weaning in conjunction with the absence of glutamine consumption impairs the functioning of macrophages, which could in turn be reversed with an in vitro supplementation with glutamine.


METHODS
Swiss Webster mice were early weaned at 14 d of age (EW group) or at 21 d of age (control group, n = 8 per group). The EW group was fed a glutamine-free diet from days 14 to 21 of life.


RESULTS
Mice in the EW group presented a significant decrease in plasma and muscle concentrations of glutamine and an increase in the activity of glutamine synthetase in the muscle. Peritoneal macrophages obtained from animals in the EW group presented a significant increase in the production of interleukin (IL)-10 and a significant decrease in the synthesis of IL-1beta, IL-6, tumor necrosis factor-alpha, nitric oxide, and hydrogen peroxide and in their ability to adhere, spread, phagocytize, and kill fungi. Glutamine in vitro supplementation reversed the decrease in IL-6, nitric oxide, and hydrogen peroxide synthesis and the decrease in the capacity to adhere, spread, and phagocytize in animals of the EW group.


CONCLUSIONS
These new data may imply that a lack of glutamine intake in early weaned mice hampers the functioning of peritoneal macrophages.
Rogero
Marcelo Macedo
MM
Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil. celo.tln@terra.com.br
Borelli
Primavera
P
Fock
Ricardo Ambrósio
RA
de Oliveira Pires
Ivanir Santana
IS
Tirapegui
Julio
J
D000818:Animals; D000831:Animals, Newborn; D019587:Dietary Supplements; D005974:Glutamate-Ammonia Ligase / Q000378:metabolism; D005973:Glutamine / Q000494:pharmacology*; D007378:Interleukins / Q000096:biosynthesis; D017737:Macrophages, Peritoneal / Q000187:drug effects* / Q000502:physiology*; D051379:Mice; D008892:Milk / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D011897:Random Allocation; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D014886:Weaning
D007378:Interleukins; D014409:Tumor Necrosis Factor-alpha; D005973:Glutamine; D009569:Nitric Oxide; D005974:Glutamate-Ammonia Ligase