Effect of Cathepsin B on cognition in trained and untrained individuals

Date

2017-05

Journal Title

Journal ISSN

Volume Title

Publisher

Abstract

Exercise contributes to improvements in cognition. However, the mechanisms behind these improvements are still not clear. The purpose of this study was to determine the effect of Cathepsin B (CTSB) on cognition in trained and untrained individuals. Furthermore, this study investigated the effects of an acute bout of exercise on CTSB. Thirty-two participants were recruited from Central Texas and categorized into untrained (<150 minutes of aerobic activity/week for the past 4 months) or trained (>400 minutes of aerobic activity/week for the past 4 months) groups. Participants came to the lab for one visit lasting two hours in duration. Upon arrival, an initial venipuncture was administered followed by three executive function tests (Switcher, Flanker, and Stroop) as well as one memory test (N-back). After completion of the cognition tests, a VO₂ max test was administered to volitional fatigue. Within fifteen minutes of completion, another venipuncture was administered followed by the same four baseline cognition tests. As expected, there was a significant difference in VO₂ max between the untrained and trained groups. However, there was no significant difference in the level of CTSB at baseline between the groups. There was no correlation between the level of CTSB and percent error on the N-back memory test on either the 1-back or 2-back trials. As expected, there was a significant decrease in reaction time and a significant increase in t-scores following the acute bout of exercise in the Switcher and Stroop test, respectively. While this acute bout of exercise did elicit improvements in executive function, there was no significant difference in post exercise level of CTSB when compared to baseline. While this study did not confirm a link between CTSB and aerobic exercise, future studies should focus on different modes and intensities of exercise in relation to CTSB. Furthermore, other neurotrophic factors and cysteine proteases should be explored as the potential link between exercise and cognition.

Description

LCSH Subject Headings

Citation