Reduced effects of age on dopamine D2 receptor levels in physically active adults

Abstract

Physical activity has been shown to ameliorate dopaminergic degeneration in non-human animal models. However, the effects of regular physical activity on normal age-related changes in dopamine function in humans are unknown. Here we present cross-sectional data from forty-four healthy human subjects between 23 and 80 years old, showing that typical age-related dopamine D2 receptor loss, assessed with PET [18F]fallypride, was significantly reduced in physically active adults compared to less active adults.

Differential regional decline in dopamine receptor availability across adulthood: Linear and nonlinear effects of age

“…The estimates reported here are somewhat lower than those seen in a recent meta‐analysis (Karrer et al, ), and could be due to our use of partial volume correction, an extremely healthy sample, or both. For instance, prior work from our lab on a subset of data from Study 1 noted that age‐related changes in the uncorrected data more closely resemble those seen in the meta‐analysis (Smith et al, ), while another study showed that compared to more sedentary adults, age‐related change in striatal D2 BP ND is less steep in physically active adults (Dang et al, ). Further, physical activity interventions have been shown to increase striatal D2 BP ND (Robertson et al, ).…”

“…Specifically, age effects on D2‐like BP ND in a subset of Study 1 participants were reported or noted in three previous publications (Dang et al, ; Dang et al, ; Smith et al, ). However, these were limited to non‐PVC striatal ROIs (Dang et al, , ) or very large cortical ROIs (i.e., frontal cortex, parietal cortex) that averaged across all gyri within a lobe (Smith et al, ). Here we focus on regional age differences in partial‐volume corrected D2‐like receptor BP ND across the adult life span using the full sample from Study 1 (not previously reported) and a new study (Study 2).…”

“…Both data sets (Study 1 and Study 2) were collected as part of large‐scale multimodal neuroimaging projects focused on decision making. Subsets of the Study 1 behavioral (Seaman et al, ), fMRI (Seaman et al, ) and PET (Dang et al, ; Dang et al, ; Smith et al, ) data were previously included in other publications. Specifically, age effects on D2‐like BP ND in a subset of Study 1 participants were reported or noted in three previous publications (Dang et al, ; Dang et al, ; Smith et al, ).…”

“…Subsets of the Study 1 behavioral (Seaman et al, ), fMRI (Seaman et al, ) and PET (Dang et al, ; Dang et al, ; Smith et al, ) data were previously included in other publications. Specifically, age effects on D2‐like BP ND in a subset of Study 1 participants were reported or noted in three previous publications (Dang et al, ; Dang et al, ; Smith et al, ). However, these were limited to non‐PVC striatal ROIs (Dang et al, , ) or very large cortical ROIs (i.e., frontal cortex, parietal cortex) that averaged across all gyri within a lobe (Smith et al, ).…”

Behavioral and neuronal interactions between exercise and alcohol: Sex and genetic differences

“…Human imaging studies have measured dopamine receptor binding to confirm that the euphoric feeling experienced during alcohol consumption is a result of endogenous dopamine release in the NAc . Additionally, physically active adults exhibited reduced age‐related striatal dopamine D2 receptor loss . In summary, these studies provide support that both moderate alcohol consumption and moderate exercise activate the mesolimbic dopaminergic reward system.…”