Author
Shukitt-Hale, Barbara | |
CAREY, AMANDA - FORMER ARS EMPLOYEE | |
JENKINS, DANIEL - UNIV OF MARYLAND | |
RABIN, BERNARD - UNIV OF MARYLAND | |
Joseph, James |
Submitted to: Neurobiology of Aging
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/1/2006 Publication Date: 8/1/2007 Citation: Shukitt Hale, B., Carey, A.N., Jenkins, D., Rabin, B.M., Joseph, J.A. 2007. Beneficial effects of fruit extracts on neuronal function and behavior in a rodent model of accelerated aging. Neurobiology of Aging.28:1187-1194. Interpretive Summary: Research has shown that exposing young rats to high energy particles increases measures of oxidative stress and inflammation and disrupts the functioning of a brain system and causes behaviors similar to that seen in old animals. Diets enhanced with 2% blueberry or strawberry extracts can slow or even reverse age-related deficits in behavior and brain activity in rats, due to their antioxidant and anti-inflammatory properties. This study evaluated the effectiveness of these diets on irradiation-induced deficits in behavior and brain activity by maintaining rats on these diets or a control diet, not containing blueberry or strawberry extract, for 8 weeks prior to being exposed to irradiation with high-energy iron particles. Irradiation decreased performance on a learning and memory maze and decreased the measure of dopamine, a brain chemical, release one month following radiation, these deficits were protected by the antioxidant, blueberry and strawberry containing, diets. The strawberry diet offered better protection against spatial deficits in the learning and memory test because strawberry-fed animals were better able to retain place information compared to control-fed animals. The blueberry diet seemed to improve learning a new method of completing the maze, which is a controlled by a different brain region. These data suggest that iron particle irradiation causes deficits in behavior and brain activity in rats which were improved by an antioxidant diet and that these fruits may be acting in different brain regions. Technical Abstract: Exposing young rats to particles of high energy and charge (HZE particles) enhances indices of oxidative stress and inflammation and disrupts the functioning of the dopaminergic system and behaviors mediated by this system in a manner similar to that seen in aged animals. Previous research has shown that diets supplemented with 2% blueberry or strawberry extracts have the ability to retard and even reverse age-related deficits in behavior and signal transduction in rats, perhaps due to their antioxidant and anti-inflammatory properties. This study evaluated the efficacy of these diets on irradiation-induced deficits in these parameters by maintaining rats on these diets or a control diet for 8 weeks prior to being exposed to whole-body irradiation with 1.5 Gy of 1 GeV/n high-energy 56Fe particles. Irradiation impaired performance in the Morris water maze and measures of dopamine release one month following radiation; these deficits were protected by the antioxidant diets. The strawberry diet offered better protection against spatial deficits in the maze because strawberry-fed animals were better able to retain place information (a hippocampally-mediated behavior) compared to controls. The blueberry diet, on the other hand, seemed to improve reversal learning, a behavior more dependent on intact striatal function. These data suggest that 56Fe particle irradiation causes deficits in behavior and signaling in rats which were ameliorated by an antioxidant diet and that the polyphenols in these fruits might be acting in different brain regions. |