Vitamin A deficiency exacerbates inflammation in a rat model of colitis through activation of nuclear factor-kappaB and collagen formation.
Inflammatory bowel disease is characterized by oxidative stress, inflammation and tissue damage. Vitamin A is an antioxidant, a regulator of epithelial proliferation and differentiation and vital for optimal immune function. To investigate the effect of vitamin A on the course of colitis, it was induced by administration of trinitrobenzene sulfonic acid (TNBS) into the colons of rats fed for 7 wk vitamin A-deficient (VAD), sufficient (VAS) or supplemented (VASUP) diet, or VAS pair-fed (PF) to the VAD rats. Inflammation and fibrosis were examined by hematoxin and eosin, and Sirius red staining. Activation of nuclear factor-kappaB (NF-kappaB) and oxidative stress were determined by electrophoretic mobility shift and plasma malondialdehyde (MDA) and RBC Cu/Zn-superoxide dismutase activity, respectively. Vitamin A deficiency in the noncolitic rats impaired food consumption and weight gain (P < 0.05) and increased plasma MDA, (P = 0.01) activity of NF-kappaB (P < 0.05) and deposition of collagen in the colon. Our data suggest that vitamin A deficiency induces colonic inflammation. Colitis is amplified by deficiency and ameliorated by supplementation of the vitamin. These findings have implications for the management of inflammatory bowel disease.
Reifen
R
R
School of Nutritional Sciences, The Hebrew University of Jerusalem, Rehovot, Israel. reifen@agri.huji.ac.il
Nur
T
T
Ghebermeskel
K
K
Zaiger
G
G
Urizky
R
R
Pines
M
M
D000818:Animals; D003092:Colitis / Q000188:drug therapy / Q000209:etiology* / Q000473:pathology; D003094:Collagen / Q000378:metabolism*; D003106:Colon / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D004435:Eating; D024202:Electrophoretic Mobility Shift Assay; D008099:Liver / Q000737:chemistry / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D016328:NF-kappa B / Q000187:drug effects / Q000378:metabolism*; D018384:Oxidative Stress; D011897:Random Allocation; D051381:Rats; D013047:Specific Pathogen-Free Organisms; D013482:Superoxide Dismutase / Q000097:blood; D014801:Vitamin A / Q000008:administration & dosage* / Q000032:analysis / Q000627:therapeutic use; D014802:Vitamin A Deficiency / Q000150:complications* / Q000473:pathology; D015430:Weight Gain
D016328:NF-kappa B; D014801:Vitamin A; D008315:Malondialdehyde; D003094:Collagen; D013482:Superoxide Dismutase