Dose-dependent effects of astaxanthin on cortical spreading depression in chronically ethanol-treated adult rats.
BACKGROUND
The consumption of alcoholic drinks is a frequent drug-abuse situation, which is associated to a wide variety of pathological disturbances affecting several organs, including the brain. We have previously shown in the developing rat brain that ethanol intake facilitates the propagation of cortical spreading depression (CSD), an excitability-related neural phenomenon present in several animal species. This electrophysiological effect was attenuated by a shrimp (Litopenaeus vannamei) carotenoids extract. Here we investigated the effects of pure astaxanthin, the main carotenoid found in shrimp, on CSD.


METHODS
Adult Wistar rats were treated per gavage, during 18 days, with 2.5, 10 or 90 microg/kg/d astaxanthin dissolved in ethanol (3 g/kg) and CSD was recorded on the cortical surface 1 to 3 days thereafter. Four groups, treated respectively with ethanol, distilled water and soybean oil with- and without astaxanthin were also studied for comparison with the ethanol + astaxanthin groups.


RESULTS
Ethanol-treated rats displayed higher CSD-velocities (mean values, in mm/min, per hour of recording ranging from 4.08 +/- 0.09 to 4.12 +/- 0.16), compared to the distilled water-group (from 3.19 +/- 0.13 to 3.27 +/- 0.06). Addition of astaxanthin to ethanol lead to lower CSD-velocities in a dose-dependent manner, ranging from 3.68 +/- 0.09 to 3.97 +/- 0.22 for the 2.5 microg/kg/d-dose, from 3.29 +/- 0.09 to 3.32 +/- 0.07 for the 10 microg/kg/d-dose, and from 2.89 +/- 0.13 to 2.92 +/- 0.11 for the 90 microg/kg/d-dose. The velocities of the soybean oil groups (with and without astaxanthin) were not statistically different from the 10 microg/kg/d astaxanthin + ethanol and distilled water groups.


CONCLUSIONS
The results demonstrate the antagonistic effect of astaxanthin against the ethanol-induced facilitation of CSD propagation. Probably carotenoid antioxidant properties are involved in such effects.
Departamento de Bioquímica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil.
Ricardo
R
Abadie-Guedes
Suzan Diniz
SD
Santos
Thiago Barbosa
TB
Cahú
Rubem Carlos Araújo
RC
Guedes
Ranilson
R
de Souza Bezerra
D000428:Alcohol Drinking / Q000503:physiopathology; D000437:Alcoholism / Q000188:drug therapy / Q000503:physiopathology*; D000818:Animals; D002492:Central Nervous System Depressants / Q000494:pharmacology; D002540:Cerebral Cortex / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D013181:Cortical Spreading Depression / Q000187:drug effects* / Q000502:physiology; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000494:pharmacology; D008297:Male; D033561:Penaeidae; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D018079:Receptors, GABA / Q000378:metabolism; D024341:Xanthophylls / Q000494:pharmacology / Q000627:therapeutic use
D002492:Central Nervous System Depressants; D017382:Reactive Oxygen Species; D018079:Receptors, GABA; D024341:Xanthophylls; D000431:Ethanol; C005948:astaxanthine