Effects of glutamine on the nuclear factor-kappaB signaling pathway of murine peritoneal macrophages.
The aim of this study was to evaluate the effect of glutamine on the expression of proteins involved in the nuclear factor-kappaB (NF-kappaB) signaling pathway of murine peritoneal macrophages. Since glutamine is essential for the normal functioning of macrophages, it was hypothesized that in vitro glutamine supplementation would increase NF-kappaB activation. Peritoneal macrophages were pretreated with glutamine (0, 0.6, 2 and 10 mM) before incubation with lipopolysaccharide (LPS), and the effects of glutamine on the production of tumor necrosis factor-alpha and on the expression and activity of proteins involved in the NF-kappaB signaling pathway were studied by an enzyme linked immuno-sorbent assay, Western blotting, and an electrophoretic mobility shift assay. Glutamine treatment (2 and 10 mM) increased the activation of NF-kappaB in LPS-stimulated peritoneal macrophages (P < 0.05). In non-stimulated cells, glutamine treatment (2 and 10 mM) significantly reduced I kappaB-alpha protein expression (P < 0.05). Glutamine modulates NF-kappaB signaling pathway by reducing the level of I kappaB-alpha, leading to an increase in NF-kappaB within the nucleus in peritoneal macrophages.
Rogero
Marcelo Macedo
MM
Department of Nutrition, School of Public Health, São Paulo University, Avenida Doutor Arnaldo, 715, São Paulo, SP, 01246-904, Brazil. mmrogero@usp.br
Borelli
Primavera
P
Fock
Ricardo Ambrósio
RA
Borges
Maria Carolina
MC
Vinolo
Marco Aurélio Ramirez
MA
Curi
Rui
R
Nakajima
Karina
K
Crisma
Amanda Rabello
AR
Ramos
Aline Domingas
AD
Tirapegui
Julio
J
D000818:Animals; D005973:Glutamine / Q000494:pharmacology*; D051550:I-kappa B Kinase / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D017737:Macrophages, Peritoneal / Q000187:drug effects* / Q000502:physiology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D016328:NF-kappa B / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D008070:Lipopolysaccharides; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D005973:Glutamine; C496564:Chuk protein, mouse; D051550:I-kappa B Kinase