2009 Annual Report
1a.Objectives (from AD-416)
LAB: Nutrition & Neurocognition
1. Determine the role of nutritional factors, especially B-vitamins and choline, in preventing age-related cognitive impairment using human intervention and population studies.
2. Characterize mechanisms by which nutritionally induced hyperhomocysteinemia affects neuronal function and cognitive performance using transgenic and other animal models of human cognitive decline.
1. Use cell models to develop mechanistic interpretations of the positive benefits of berry polyphenols and fatty acids by examining their direct effects on deficits in stress and protective signaling.
2. Establish the effects of dietary berry fruit extracts and/or fatty acids on behavioral and neuronal deficits in aging to assess the mechanisms involved and the most effective polyphenols/fatty acids in animal and human models.
1b.Approach (from AD-416)
LAB: Nutrition & Neurocognition
With the population aging, the imperativeness to understand and prevent age-related cognitive decline and disability grows more important. We approach this problem with nutritional studies in human populations and in studies of animal models. Observational and cohort studies in humans examine the association of modifiable nutritional factors especially B vitamins, vitamin D, and polyunsaturated fatty acids with the trajectory of cognitive decline and measurable brain volumes with age. Intervention studies with B vitamins to lower homocysteine levels in blood and protect against neurological and vascular degeneration examine our ability to delay cognitive decline, dementia, and disability.
Genotyping focusing on methylation pathways provide insight into how genetic variability may modify or modulate the neurological response to nutrition and dietary factors. Animal models of aging and dementia are employed to examine the mechanism of nutritional modification of neural and cerebrovascular degeneration with effects on behavior. Rodents are made deficient in B vitamins or polyunsaturated fatty acids or choline and effects on brain function (behavior), brain biochemistry, and brain histology provide insights into pathways by which nutritional perturbations influence aging brain chemistry and function.
The focus of the current project is to elucidate the mechanisms involved in the beneficial effects of berry fruit and polyunsaturated fatty acids (PUFAs) from fish or nut oils on reducing neurodegeneration mediated by oxidative stress (OS) and inflammation (INF). Mixed neuron/ glial cultures obtained from rats of different ages will be employed to delineate the neuroprotective effects of berry fruit or PUFA against OS/INF and subsequent stress mediated by glial cells. Additionally, muscarinic receptor-transfected COS-7 cells will be used to assess OS/INF localization and the effects of membrane lipids on the cellular responses to OS/INF. Extensive motor and cognitive assessments will also be made of senescent animals fed diets containing berry fruit or PUFAs. Finally, we will translate the behavioral findings obtained in our animal studies to the human condition by examining the effects of berry fruit or walnut supplementation on human gait and motor ability. This project will contribute to fundamental new knowledge of the putative role of berry fruit and PUFAs on reducing OS/INF and behavioral deficits in aging. These studies will span basic cellular signaling, animal behavior and cognition, and human motor abilities, allowing for a comprehensive examination of the beneficial effects of berry fruit and nutritional PUFAs on the aging brain.
This new Project Plan was recently certified through ARS Office of Scientific Quality Review (OSQR) and will report progress in 2010-2014. For further details on current work see the 2009 report for project 1950-51000-063-00D.
This new Project Plan was recently certified through ARS Office of Scientific Quality Review (OSQR) and will report accomplishments in 2010-2014. For further details on current accomplishments see the 2009 report for project 1950-51000-063-00D.