Intermittent Binge-Intake Model in Mice

This research investigates the influence of food availability patterns on binge-eating behaviors and anxiety-like behaviors in binge-eating disorders, or BED. Utilizing a novel M&M's mouse model, we compare the effects of continuous versus intermittent access to palatable foods. The objective is to develop accessible models for basic binge-eating disorder research.

Our protocol provides a quick, easy, and accessible M&M-based model. It is validated through open-field test results, effectively replicating anxiety-like behaviors. Additionally, it offers efficient and cost-effective approach to studying the binge-eating model, paving the way for further investigation into the underlying neural mechanisms in disorders like BED.

We aim to further investigate the complex relationship between food availability, eating behaviors, and neural mechanisms, uncovering insights that could lead to more effective treatments for binge-eating disorders and obesity, and ultimately, improve therapeutic strategies and health outcomes for those affected by these conditions. After seven days of habituation period, randomly assign the rodents into three groups. Provide all subjects with access to HPF for two hours to minimize neophobia toward the HPF.

Provide the specified feeding conditions shown here for each group for 26 days. Place the standard chow on the cage racks and the HPF in small plastic containers. Randomly position these containers at the corners of the cages.

Measure the body weight, chow food consumption, palatable food consumption, and water intake of the mouse. Binge-eating behavior was successfully established by day eight and maintained through day 26 in the intermittent group, which showed significantly higher caloric intake compared to the chow group and continuous group. On test days, the intermittent group consumed more calories than the chow and continuous groups, primarily from palatable food rather than standard chow, with no significant differences between the chow and continuous groups.

Standard chow consumption did not differ among the groups. But on day 26, the intermittent group consumed significantly more HPF than the continuous group. For arena-based measurements, use a square chamber made of black non-porous plastic.

Clean the chamber before and between uses with 70%volume per volume ethanol to eliminate odor cues. Place a camera above the apparatus to record an optimal exploration view during sessions. Adjust the alignment to ensure comprehensive coverage of the entire arena.

Activate the video tracking software using the autostart feature, which detects the investigator and begins recording when the investigator is no longer in the camera's focus. Then, gently hold a single mouse by its tail and place it in the center of the open-field maze. Allow the mouse to move freely along the maze for five minutes while the tracking software records its movement.

At the end of the trial period, remove the animal from the arena and return it to its home cage. Next, visually count the feces deposited in the maze and record the count for later analysis. Remove all fecal pellets and clean any urine stains.

Spray the mazes floor and walls with 70%ethanol, then wipe them with a clean paper towel, and allow the ethanol to dry completely. After testing all animals, return to the vivarium, clean the arena, and organize all used materials. Chow group mice spent more time in the central area of the open-field test compared to both the intermittent and continuous groups, with no significant differences between the intermittent and continuous groups.

The mice and the chow group traveled more in the central region than the intermittent and continuous groups. But no differences were observed in the distance traveled in the peripheral region among all groups. During the open-field test, the chow group mice showed significantly more entries into the central zone than the intermittent and continuous groups.