Related Experiment Video
Updated: May 5, 2026
Assessing Burrowing, Nest Construction, and Hoarding in Mice
Published on: January 5, 2012
Obsessive-compulsive-like behaviors in house mice are attenuated by a probiotic (Lactobacillus rhamnosus GG)
Pranish A Kantak1, Dylan N Bobrow, John G Nyby
1Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, USA.
Abstract:
Two experiments examined probiotic pretreatment (Lactobacillus rhamnosus GG) on obsessive-compulsive disorder (OCD)-like behavior induction by RU 24969 in BALB/cJ house mice. In the first experiment, two groups were defined by their daily pretreatment by oral gavage of either (a) L. rhamnosus (1×10⁹ CFU/day) or (b) the saline vehicle. Both a 2- and 4-week probiotic pretreatment attenuated OCD-like behavior induction (increased perseverative open-field locomotion, stereotypic turning, and marble burying) relative to saline pretreatment. Experiment 2 re-examined the 2-week probiotic pretreatment while also comparing it to a 4-week fluoxetine pretreatment. Again, groups were defined by daily pretreatment of either (a) L. rhamnosus for 2 weeks, (b) the saline vehicle for 2 weeks, or (c) fluoxetine (10 mg/kg) for 4 weeks. Pretreatment by either L. rhamnosus or fluoxetine blocked the induction of OCD-like behavior compared with saline pretreatment. Thus the 2-week probiotic pretreatment was again effective. Although side effects of fluoxetine or L. rhamnosus on androgen-dependent behaviors could not be demonstrated, L. rhamnosus treatment appeared comparable to fluoxetine treatment in attenuating mouse OCD-like behaviors.
Insights
Probiotic pretreatment with Lactobacillus rhamnosus GG significantly reduced obsessive-compulsive disorder (OCD)-like behaviors in mice. This probiotic intervention showed comparable efficacy to fluoxetine in attenuating these behaviors.
Area of Science:
- Neuroscience
- Microbiology
- Pharmacology
Background:
- Obsessive-compulsive disorder (OCD) is a debilitating mental health condition.
- The gut-brain axis is increasingly recognized for its role in neurological disorders.
- Investigating novel therapeutic avenues for OCD is crucial.
Purpose of the Study:
- To evaluate the efficacy of Lactobacillus rhamnosus GG (L. rhamnosus) as a probiotic pretreatment in an animal model of OCD.
- To compare the effects of L. rhamnosus with fluoxetine, a standard OCD treatment.
Main Methods:
- Two experiments were conducted using BALB/cJ mice.
- Mice received daily oral gavage of L. rhamnosus or saline vehicle for 2 or 4 weeks.
- OCD-like behaviors, including perseverative locomotion, stereotypic turning, and marble burying, were induced by RU 24969.
- Experiment 2 included a fluoxetine pretreatment group.
Main Results:
- Both 2- and 4-week L. rhamnosus pretreatment attenuated RU 24969-induced OCD-like behaviors compared to saline.
- L. rhamnosus pretreatment was effective in blocking OCD-like behavior induction.
- L. rhamnosus demonstrated comparable efficacy to fluoxetine in reducing mouse OCD-like behaviors.
Conclusions:
- Lactobacillus rhamnosus GG pretreatment effectively attenuates OCD-like behaviors in a mouse model.
- Probiotic intervention with L. rhamnosus shows promise as a potential therapeutic strategy for OCD.
- L. rhamnosus may offer a comparable alternative to traditional pharmacotherapy for OCD.
