Astaxanthin ameliorates the redox imbalance in lymphocytes of experimental diabetic rats.
Diabetes mellitus is a syndrome of impaired insulin secretion/sensitivity and frequently diagnosed by hyperglycemia, lipid abnormalities, and vascular complications. The diabetic 'glucolipotoxicity' also induces immunodepression in patients by redox impairment of immune cells. Astaxanthin (ASTA) is a pinkish-orange carotenoid found in many marine foods (e.g. shrimp, crabs, salmon), which has powerful antioxidant, photoprotective, antitumor, and cardioprotective properties. Aiming for an antioxidant therapy against diabetic immunodepression, we here tested the ability of prophylactic ASTA supplementation (30 days, 20 mg ASTA/kg BW) to oppose the redox impairment observed in isolated lymphocytes from alloxan-induced diabetic Wistar rats. The redox status of lymphocytes were thoroughly screened by measuring: (i) production of superoxide (O(2)(-)), nitric oxide (NO), and hydrogen peroxide (H(2)O(2)); (ii) cytosolic Ca(2+); (iii) indexes of oxidative injury; and (iv) activities of major antioxidant enzymes. Hypolipidemic and antioxidant effects of ASTA in plasma of ASTA-fed/diabetic rats were apparently reflected in the circulating lymphocytes, since lower activities of catalase, restored ratio between glutathione peroxidase and glutathione reductase activities and lower scores of lipid oxidation were concomitantly measured in those immune cells. Noteworthy, lower production of NO and O(2)(-) (precursors of peroxynitrite), and lower cytosolic Ca(2+) indicate a hypothetical antiapoptotic effect of ASTA in diabetic lymphocytes. However, questions are still open regarding the proper ASTA supplementation dose needed to balance efficient antioxidant protection and essential NO/H(2)O(2)-mediated proliferative capacities of diabetic lymphocytes.
Postgraduate Program, Human Movement Sciences, Institute of Physical Activity and Sport Sciences, Universidade Cruzeiro do Sul, ZIP 01506000, Sao Paulo, SP, Brazil; Postgraduate Program, Health Sciences, CBS, Universidade Cruzeiro do Sul, ZIP 08060070, Sao Paulo, SP, Brazil.
Rosemari
R
Otton
Douglas Popp
DP
Marin
Anaysa Paola
AP
Bolin
Rita de Cássia Macedo dos
Rde C
Santos
Tatiana Geraldo
TG
Polotow
Sandra Coccuzzo
SC
Sampaio
Marcelo Paes
MP
de Barros
D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D002118:Calcium / Q000378:metabolism; D049109:Cell Proliferation; D003920:Diabetes Mellitus / Q000178:diet therapy*; D006861:Hydrogen Peroxide / Q000378:metabolism; D008214:Lymphocytes / Q000166:cytology / Q000378:metabolism*; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism; D010084:Oxidation-Reduction; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D024341:Xanthophylls / Q000627:therapeutic use
D000975:Antioxidants; D017382:Reactive Oxygen Species; D024341:Xanthophylls; D009569:Nitric Oxide; C005948:astaxanthine; D006861:Hydrogen Peroxide; D002118:Calcium