Exercise Neuroprotection in a Rat Model of Binge Alcohol Consumption
Article first published online: 17 DEC 2009
Copyright © 2009 by the Research Society on Alcoholism
Alcoholism: Clinical and Experimental Research
Volume 34, Issue 3, pages 404–414, March 2010
How to Cite
Leasure, J. L. and Nixon, K. (2010), Exercise Neuroprotection in a Rat Model of Binge Alcohol Consumption. Alcoholism: Clinical and Experimental Research, 34: 404–414. doi: 10.1111/j.1530-0277.2009.01105.x
- Issue published online: 2 MAR 2010
- Article first published online: 17 DEC 2009
- Received for publication June 12, 2009; accepted September 29, 2009.
- Dentate Gyrus;
- Adult Neurogenesis;
Background: Excessive alcohol intake produces structural and functional deficits in corticolimbic pathways that are thought to underlie cognitive deficits in the alcohol use disorders (AUDs). Animal models of binge alcohol administration support the direct link of high levels of alcohol consumption and neurotoxicity in the hippocampus and surrounding cortex. In contrast, voluntary wheel running enhances hippocampal neurogenesis and generally promotes the health of neurons.
Methods: We investigated whether voluntary exercise prior to binge alcohol exposure could protect against alcohol-induced cell loss. Female Long-Evans rats exercised voluntarily for 14 days before undergoing 4 days of binge alcohol consumption. Brains were harvested immediately after the last dose of alcohol and examined for various histological markers of neurodegeneration, including both cell death (FluoroJade B) and cell birth (Ki67) markers.
Results: Rats that exercised prior to binge exposure were significantly less behaviorally intoxicated, which was not a result of enhanced hepatic metabolism. Rats that exercised prior to binge alcohol consumption had reduced loss of dentate gyrus granule cells and fewer FluoroJade B positive cells in the dentate gyrus and associated entorhinal-perirhinal cortex compared to nonexercisers. However, exercise did not protect against cell death in the piriform cortex nor protect against alcohol-induced decreases in cell proliferation, evidenced by a similar alcohol-induced reduction in Ki67 labeled cells between exercise and sedentary rats.
Conclusions: We conclude that exercise can reduce behavioral sensitivity to ethanol intoxication and protect vulnerable brain areas from alcohol-induced cell death. Exercise neuroprotection of alcohol-induced brain damage has important implications in understanding the neurobiology of the AUDs as well as in developing novel treatment strategies.