Exogenous glutamine impairs neutrophils migration into infections sites elicited by lipopolysaccharide by a multistep mechanism

• Published in: Amino acids 2019-03, Vol.51 (3), p.451-462
• Main Authors: Santos, Andressa Cristina Antunes, Hebeba, Cristina Bichels, Hastreiter, Araceli Aparecida, de Oliveira, Dalila Cunha, Naoto Makiyama, Edson, Farsky, Sandra Helena Poliselli, Borelli, Primavera, Fock, Ricardo Ambrosio
• Format: Article
• Language: English
• Subjects: Amino acids; Analytical Chemistry; Animal models; Animals; Biochemical Engineering; Biochemistry; Biomedical and Life Sciences; Blood circulation; Cell Adhesion Molecules - genetics; Cell Adhesion Molecules - metabolism; Cell Movement - drug effects; E coli; Endothelium; Endotoxemia; Endotoxemia - chemically induced; Endotoxemia - drug therapy; Endotoxemia - metabolism; Endotoxemia - pathology; Gene Expression Regulation; Glutamine; Glutamine - administration & dosage; Glutamine - pharmacology; Immune response; Immune system; Inflammation; Injection; Intravenous administration; Leukocyte migration; Leukocytes; Leukocytes (neutrophilic); Life Sciences; Lipopolysaccharides; Lipopolysaccharides - toxicity; Lungs; Male; Mice; Mice, Inbred BALB C; Neurobiology; Neutrophils; Neutrophils - drug effects; Neutrophils - metabolism; Original Article; Peritoneum; Peritoneum - drug effects; Peritoneum - metabolism; Pneumonia - chemically induced; Pneumonia - drug therapy; Pneumonia - metabolism; Pneumonia - pathology; Proteomics; Rodents
• ISSN: 0939-4451; 1438-2199
• DOI: 10.1007/s00726-018-2679-3

Glutamine (GLN) is the most abundant free amino acid in the body, and is considered as a conditionally essential amino acid under stress conditions, acting as an important modulator of the immune response. We here investigated the role of exogenous GLN treatment on leukocyte migration after the onset of endotoxemia and the intracellular mechanisms of GLN actions on neutrophils. Two in vivo models of endotoxemia caused by lipopolysaccharide of Escherichia coli (LPS) injection were carried out in male outbred Balb/C mice 2–3 months old, as follow: (1) LPS (50 μg/kg) was intravenously injected 1 h prior to intravenous injection of GLN (0.75 mg/kg) and samples were collected 2 h later to investigate the role of GLN on the acute lung inflammation; (2) LPS (1 mg/kg) was intraperitoneally injected 1 h prior to intravenous injection of GLN (0.75 mg/kg) and samples were collected 18 h later to measure the effects of GLN on local and later phases of inflammation in the peritoneum. Results showed that GLN administration reduced the number of neutrophils in the inflamed lungs, partially recovery of the reduced number of leukocytes in the blood; reduced adhesion molecules on lung endothelium and on circulating neutrophils. Moreover, GLN treatment diminished the number of neutrophils, levels of chemotactic cytokine CXCL2 in the inflamed peritoneum, and neutrophils collected from the peritoneum of GLN-treated mice presented lower levels of Rho, Rac, and JNK. Together, our data show novel mechanisms involved in the actions of GLN on neutrophils migration.