Prevention of experimental autoimmune encephalomyelitis in Lewis rats by a novel fungal source of gamma-linolenic acid.
The effects of oral administration of linoleic- and gamma-linolenic-acid-rich oils on the clinical and histopathological manifestations of experimental autoimmune encephalomyelitis (EAE) were investigated in Lewis rats 7 d post-inoculation. gamma-Linolenic-acid-rich fungal (Mucor javanicus) oil at 500 mg/kg body weight abrogated clinical and histological signs of EAE although at doses of 200 and 1000 mg/kg body weight it was only effective in delaying the onset of clinical disease. Linoleic-acid-rich safflower-seed (Carthamus tinctorius) oil at 500, 750 and 1000 mg/kg body weight decreased the severity of clinical EAE disease in a dose-dependent manner. The effects in healthy animals of orally administered gamma-linolenic-acid-rich fungal oil (500 mg/kg body weight) and linoleic-acid-rich safflower-seed oil (1000 mg/kg body weight) on splenic lymphocyte proliferative responses to the T-cell mitogen concanavalin-A (Con A), membrane fatty acid composition and lymphocyte sub-sets were also studied. Both treatments enhanced the T-cell proliferative response to Con A. There was no significant effect on the proportion of splenic CD8+ or CD4+ lymphocytes. Compositional studies on splenic phosphoglyceride fatty acids of oil-treated animals suggest the above responses were associated with increases in spleen dihomo-gamma-linolenic and arachidonic acids.
Immunology Department, United Medical School, Guy's Hosptial, London.
L S
LS
Harbige
N
N
Yeatman
S
S
Amor
M A
MA
Crawford
D000284:Administration, Oral; D000818:Animals; D002455:Cell Division; D003208:Concanavalin A / Q000494:pharmacology; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000276:immunology / Q000378:metabolism / Q000517:prevention & control*; D006168:Guinea Pigs; D050356:Lipid Metabolism; D008934:Mitogens / Q000494:pharmacology; D009089:Mucor / Q000737:chemistry*; D051381:Rats; D011917:Rats, Inbred Lew; D012450:Safflower Oil; D013154:Spleen / Q000276:immunology / Q000378:metabolism; D013601:T-Lymphocytes / Q000502:physiology; D017962:alpha-Linolenic Acid / Q000008:administration & dosage; D017965:gamma-Linolenic Acid / Q000008:administration & dosage*
D008934:Mitogens; D017962:alpha-Linolenic Acid; D003208:Concanavalin A; D017965:gamma-Linolenic Acid; D012450:Safflower Oil