Development of an Open Face Home Cage Running Wheel for Testing Activity-Based Anorexia and Other Applications

Mice on an activity-based anorexia model with access to a running wheel have decreased probability of survival when food restricted. A, Description and time course of the following four groups: (1) Ad lib + dummy, (2) Ad lib + wheel, (3) FR + dummy, and (4) FR + wheel. B, FR mice with access to a running wheel (red) are removed from the study sooner when food restricted compared with Ad lib mice with a running wheel (black). Extended Data Figure 2-1 indicates that mice did not lose weight to the humane end point when on 6 h food restriction for up to 10 d. As such, we added a 3 h food restriction after 3 d of 6 h food restriction.

FR Mice with access to a running wheel lose more body weight. A, Time course of daily body weight measurements taken at 9:00 A.M. each day during baseline, 6 h food restriction, and then 3 h food restriction. B, Body weight measurements from Ad lib (open bars) or FR (filled bars) mice with access to a dummy wheel or running wheel on day 11, the time point before some mice were removed from the study. C, Time course of food consumption each day during baseline, after the 3 h FR period or after the 6 h FR period. D, Food intake over the 24 h period preceding the time point before some mice were removed from the study from Ad lib (open bars) and FR (filled bars) mice. E, Daily water consumption during baseline, 3 h FR, and 6 h FR. FR increased water consumed in both groups regardless of access to the running wheel. F, Water consumption over the 24 h period preceding the time point before some mice were removed from the study from Ad lib (open bars) and FR (filled bars) mice that have access to a dummy or running wheel. Bars represent the mean ± SEM. Symbols represent individual mice.

Distance traveled increases with food restriction. A, Daily distance traveled on the running wheel in Ad lib (open circles) or FR (filled circles) mice. B, Averaged distance traveled over 24 h measured on day 7 or day 11 from Ad lib (open bars) or FR (filled bars) mice. C, Daily anticipatory activity measured within the 3 h period before food delivery in Ad lib or FR mice. D, Averaged 3 h anticipatory activity measured on day 7 or day 11 from Ad lib (open bars) or FR (filled bars) mice. E, Daily distance traveled measured during the 3 h food availability period from Ad lib or FR mice. F, Averaged distance traveled during the first 3 h of the food availability period on day 7 or day 11 from Ad lib or FR mice. G, Time course of daily postprandial activity over 3 h after food access from Ad lib or FR mice. H, Averaged 3 h postprandial distance traveled on day 7 or day 11 from Ad lib or FR mice. Bars represent the mean ± SEM. Symbols represent individual mice.

Circadian pattern of wheel running. A, Over a 24 h period, hourly wheel running is enhanced in FR mice (filled circles) compared with Ad lib mice (open circles) except during the food availability period. This data were recorded on day 10. Shaded boxes represent the dark cycle. Hashed lines represent the food availability period. B, Daily wheel running in Ad lib mice on day 10 as identified by clockwise running (open bars) and counterclockwise running (filled bars). C, Daily wheel running in FR mice on day 10 as identified by clockwise running (open bars) and counterclockwise running (filled bars). Bars represent the mean ± SEM. Symbols represent individual mice.