VITAMIN A DEFICIENCY INDUCES PROOXIDANT ENVIRONMENT, INFLAMMATION CHANGES IN LIP- IDS METABOLISM AND HISTOARCHITECTURE IN AORTA

We evaluated whether nutritional vitamin A deficiency generates oxidative stress and inflammation in rat aorta. Rats fed the vitamin A- deficient diet were characterized by sub-clinical plasma retinol concentration and showed increased serum and aorta concentrations of TBARS Lower activities of CuZnSOD, GPx, and CAT were observed in aorta of the vitamin A-deficient group. The binding activity of NF- kB was higher in vitamin A- deficient animals. NO production evaluated as nitrite increased in aorta and serum, associated with a higher expression of iNOS, eNOS and COX-2 in aorta of vitamin A-deficient rats. When the lipid metabolism in the aorta of rats fed on a vitamin-A-deficient diet was evaluated, we observed a hypolipidemic effect (lower serum triglyceride and cholesterol levels) and a decreased serum paraoxonase 1/arylesterase activity. The triglycerides, fatty acid synthesis and mRNA expression of diacylglycerol acyltransferase 1, total cholesterol, free and esterified cholesterol, and phospholipids were increased in the aorta of vitamin-A-deficient rats. The phospholipid compositions showed an increase in phosphatidylcholine (PC), phosphatidylinositol plus phosphatidylserine and phosphati-dylethanolamine, a decrease in sphingomyelin. In the aorta, the increase in triglycerides was associated with The increased PC content was attributed to an increased synthesis, as measured by [methyl-(14)C]choline incorporation into PC and high CTP:phosphocholine cytidylyltransferase-alpha mRNA expression. The lipoprotein lipase and lectin-like oxidized low-den-sity lipoprotein receptor 1 mRNA expression levels increased in the aorta of vitamin-A-deficient animals. The incorporatio