Exploration of Alzheimer's disease-related gene expression following high-intensity and moderate-intensity exercise interventions

Objectives

There are currently 29 genome regions that demonstrate associations with Alzheimer's disease (AD) risk. Regular physical exercise can promote systemic change in gene expression and may modify the risk of cognitive decline and AD. This study is a secondary analysis of a randomised controlled trial and examines the effect of a six-month exercise intervention versus control on AD-related gene expression.

Design

Single-site parallel pilot randomised controlled trial.

Methods

91 cognitively unimpaired older adults were enrolled in the Intense Physical Activity and Cognition (IPAC) study. Participants were randomised into one of three groups: high-intensity exercise, moderate-intensity exercise, or inactive control for six months. Blood samples were collected prior to, and within two weeks of intervention completion, for later expression analysis of 96 genes. To explore the relationship between changes in gene expression and the intervention groups, an interaction term (“time point × intervention group”) was subsequently used.

Results

There were no significant differences in gene expression between the three intervention groups at baseline, nor after the intervention. Within groups, five genes were upregulated, seven were downregulated and the remainder remained unchanged. None of the examined genes showed significant change from pre- to post-intervention in the exercise groups compared to the control.

Conclusions

Exercise does not change AD-related gene expression in cognitively unimpaired older adults. Several gene expression targets have been identified for further study.