title: Arginine-supplemented diet decreases expression of inflammatory cytokines and improves survival in burned rats.
abstract: BACKGROUND
  We examined whether the expression of inflammatory cytokines in organs was influenced by the enteral diet supplemented with arginine in burned rats.
  
  
  METHODS
  Male Wistar rats weighing about 200 g underwent catheter jejunostomy and received scald burns covering 30% of the whole-body surface area. Animals were divided into two groups: a control group (no supplemental arginine, n = 12) and an arginine group (supplemental arginine: 7.7 g/L, n = 10), which continuously received total enteral nutrition for 7 days (250 kcal/kg/d, 1.72 gN/kg/d). The following were measured after the experiment: (1) messenger RNA (mRNA) expression of tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin-1beta (IL-1beta), and IL-6 in the spleen, thymus, lung, and liver by a semiquantitative reverse transcription-polymerase chain reaction method, (2) inflammatory cytokines in the plasma and supernatant of cultured splenic lymphocytes by enzyme-linked immunosorbant assay, (3) nitric oxide (NO) product, NO2-/NO3-, in the plasma and supernatant of cultured splenic lymphocytes by the Griess method, and (4) survival rate by the Kaplan-Meier method.
  
  
  RESULTS
  The mRNA expression of TNF-alpha was significantly decreased in the spleen and lung (p < .01, p < .05), IFN-gamma in the lung (p < .05), IL-1beta in the spleen (p < .05), and IL-6 in the thymus and liver (p < .05, p < .05) in the arginine group when compared with the control group. The production of TNF-alpha by splenic lymphocytes was suppressed in the arginine group in both concanavalin A (Con A)-treated and -untreated cultures (p < .01, p < .05). The production of IFN-gamma by splenic lymphocytes treated with Con A was suppressed in the arginine group (p < .05). The NO product in the supernatant without Con A was increased in the arginine group (p < .05). The mortality rate of the arginine group (0%) was lower than that in the control group (33.3%) on day 7 after the burn injury (p < .05).
  
  
  CONCLUSIONS
  The data suggest that dietary arginine supplementation decreases the mRNA expression of inflammatory cytokines in organs and improves the survival rate after thermal injury.
authors.affiliation: Department of Surgery II, Kochi Medical School, Nankoku, Japan.
authors.forename: X L
authors.initials: XL
authors.lastname: Cui
authors.forename: M
authors.initials: M
authors.lastname: Iwasa
authors.forename: Y
authors.initials: Y
authors.lastname: Iwasa
authors.forename: S
authors.initials: S
authors.lastname: Ogoshi
mesh_terms: D000818:Animals; D001120:Arginine / Q000008:administration & dosage / Q000627:therapeutic use*; D001835:Body Weight / Q000187:drug effects; D002056:Burns / Q000188:drug therapy* / Q000276:immunology; D003208:Concanavalin A / Q000494:pharmacology; D004032:Diet; D004750:Enteral Nutrition; D007371:Interferon-gamma / Q000097:blood; D007378:Interleukins / Q000097:blood*; D007582:Jejunostomy; D008099:Liver / Q000033:anatomy & histology / Q000187:drug effects / Q000276:immunology; D008168:Lung / Q000033:anatomy & histology / Q000187:drug effects / Q000276:immunology; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013154:Spleen / Q000033:anatomy & histology / Q000187:drug effects / Q000276:immunology; D013950:Thymus Gland / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D014945:Wound Healing / Q000187:drug effects
chemical_list: D007378:Interleukins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D003208:Concanavalin A; D009569:Nitric Oxide; D007371:Interferon-gamma; D001120:Arginine