Genes, Exercise, Memory and Neurodegeneration

The primary purpose of this pilot study is to determine whether African Americans with mild Alzheimer's disease (AD) can be enrolled and retained in a 6-month aerobic exercise-training study.

This study will examine the effects of aerobic exercise-training on neurocognitive function, and on cerebral glucose homeostasis. It is yet to be determined whether African Americans with mild AD can be recruited into such a study, nor has the relationship of fitness adaptation to neurocognitive function been systematically examined in this population. In addition to the goal of assessing the intervention effects, the study will evaluate the differential relationships of APOE to aerobic fitness-induced changes in neurocognition. The long-term goal is to explore the mechanism by which fitness adaptation exerts an effect on neurocognition, notably, low levels of high-density lipoprotein cholesterol (HDL-C), elevated inflammation (C-reactive protein (CRP) and interleukins (IL-1A)), deranged glucose homeostasis, hypertension and endothelia dysfunction are precursors of arteriolosclerosis, decreased cerebral perfusion and oxygen deprivation, all of which may increase AD risk. Because many of these putative AD risk factors are susceptible to lifestyle alterations, the study will also assess their roles in aerobic fitness-related improvements in cognitive function and reduction in AD risk.

Inclusion Criteria: Age over 60 years Ability to exercise vigorously without harm Mild AD Study partner In good general health Willing to exercise for 6 months Body Mass Index (BMI) less than 37 Women participants must be postmenopausal for at least 2 years, and maintain current hormone replacement therapy status and allowed medication usage for the duration of the study Exclusion Criteria: MMSE score below 20 TG (Triglyceride) greater than 400 mg/dl LDL-C levels greater than 95% or HDL-C levels less than 10% of age and sex-adjusted norms

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