Astaxanthin reduces oxidative stress, but not aortic damage in atherosclerotic rabbits.
We evaluated whether carotenoid astaxanthin (ASX) could prevent oxidative and atherosclerotic damage in rabbits. Rabbits received regular chow (control) or an atherogenic diet (1% cholesterol) alone or supplemented with 50, 100, and 500 mg% ASX for 60 days (n = 5-9 per group). The atherogenic diet increased the serum cholesterol levels and the ratio of the intima/media area in the aortic arch. These changes were not prevented by ASX. Atherosclerotic rabbits showed increased aortic lipid peroxidation and nonprotein thiol group (NPSH) levels along with inhibition of glutathione peroxidase (GSH-Px). All ASX doses attenuated lipid peroxidation and the increase in NPSH but not the inhibition of GSH-Px. Aortic superoxide dismutase (SOD), catalase (CAT), and thioredoxin reductase (TrxR) activities were enhanced in atherosclerotic rabbits. Although all ASX doses prevented the increase in SOD activity, only 100 and 500 mg% ASX prevented the increase in CAT activity. Furthermore, these same doses partially prevented the increase in TrxR activity, while 50 mg% ASX completely prevented the effects of the atherogenic diet on this enzyme. However, ASX did not attenuate the hypercholesterolemia or the atherosclerotic lesions caused by the atherogenic diet at any of the doses evaluated. Our results indicate that although ASX did not prevent hypercholesterolemia or atherosclerotic lesions, it could play a beneficial role by preventing lipid peroxidation and changes in antioxidant enzyme activities.
Augusti
Paula R
PR
Department of Biochemistry, Institute of Health Basic Sciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
Conterato
Greicy M M
GM
Somacal
Sabrina
S
Sobieski
Rocheli
R
Quatrin
Andréia
A
Maurer
Luana
L
Rocha
Marta P
MP
Denardin
Ione T
IT
Emanuelli
Tatiana
T
D000818:Animals; D001011:Aorta / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology*; D050197:Atherosclerosis / Q000188:drug therapy*; D002374:Catalase / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D004036:Diet, Atherogenic; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005979:Glutathione Peroxidase / Q000037:antagonists & inhibitors; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects*; D011817:Rabbits; D013438:Sulfhydryl Compounds / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D013880:Thioredoxin-Disulfide Reductase / Q000378:metabolism; D024341:Xanthophylls / Q000008:administration & dosage / Q000494:pharmacology
D013438:Sulfhydryl Compounds; D017392:Thiobarbituric Acid Reactive Substances; D024341:Xanthophylls; C005948:astaxanthine; D002784:Cholesterol; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D013880:Thioredoxin-Disulfide Reductase