Canthaxanthin and excess vitamin A alter alpha-tocopherol, carotenoid and iron status in adult rats

J Nutr. 1991 Oct;121(10):1649-55. doi: 10.1093/jn/121.10.1649.

Abstract

beta-Carotene and excess vitamin A have been shown to reduce plasma alpha-tocopherol when fed to young rats. The present study assessed the effects of beta-carotene, excess vitamin A and canthaxanthin (4,4'-diketo-beta-carotene) on carotenoid, alpha-tocopherol and iron status in adult retired breeder rats. Male 8- to 10-mo-old rats (10/group) were fed varying levels of vitamin A as retinyl palmitate, beta-carotene and canthaxanthin ad libitum for 8 wk. The AIN-76A diet was modified to contain 16% (wt/wt) fat and 50% carbohydrate (control) plus beta-carotene or canthaxanthin at 0, 0.048 (BC1 or CX1) and 0.2% (BC2 or CX2) of the diet. These compounds were fed with and without excess retinyl palmitate (RP, 220 mg/kg). Higher relative liver weights were observed in CX- and RP-fed groups. Plasma retinyl esters were detected in all RP-fed groups. Plasma retinyl palmitate was 1.6- and 1.5-fold higher in RP-BC and RP-CX groups, respectively, than in the RP groups. Plasma and liver beta-carotene and canthaxanthin were 11-54% and 26-74% lower, respectively, with excess retinyl palmitate feeding. Feeding canthaxanthin and retinyl palmitate but not beta-carotene, resulted in lower levels of plasma alpha-tocopherol. Liver non-heme iron levels were also lower in CX-fed rats irrespective of retinyl palmitate feeding. These results extend to adult rats previous findings that excess retinyl palmitate alters vitamin E and carotenoid status prior to the manifestation of clinical signs of hypervitaminosis A. Additionally, canthaxanthin feeding lowers alpha-tocopherol and iron status in adult rats.

MeSH terms

  • Administration, Oral
  • Animals
  • Body Weight / drug effects
  • Canthaxanthin / administration & dosage
  • Canthaxanthin / pharmacology*
  • Carotenoids / metabolism*
  • Cholesterol / blood
  • Iron / metabolism*
  • Liver / drug effects
  • Liver / metabolism
  • Male
  • Rats
  • Rats, Inbred Strains
  • Triglycerides / blood
  • Vitamin A / administration & dosage
  • Vitamin A / blood
  • Vitamin A / pharmacology*
  • Vitamin E / metabolism*

Substances

  • Triglycerides
  • Vitamin A
  • Vitamin E
  • Carotenoids
  • Canthaxanthin
  • Cholesterol
  • Iron