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Polyethylene Glycol 3350 Changes Stool Consistency and the Microbiome but not Behavior of CD1 Mice
Salman S Salman1, Kent C Williams1,2, Pedro Marte-Ortiz3
1Division of Pediatric Gastroenterology, Nationwide Children's Hospital.
Insights
Polyethylene Glycol 3350 (PEG3350), a common laxative, did not induce anxiety-like behaviors in mice, despite altering stool consistency and gut microbiome. This study investigated PEG3350
Area of Science:
- Pharmacology
- Neuroscience
- Microbiome Research
Background:
- Polyethylene Glycol 3350 (PEG3350) is a widely used laxative for pediatric constipation.
- Reports suggest potential links between PEG3350 and behavioral changes like anxiety in children.
- This study aimed to investigate the potential for PEG3350 to induce anxiety-like behaviors.
Purpose of the Study:
- To determine if daily administration of PEG3350 causes anxiety-like behaviors in mice.
- To assess the impact of PEG3350 on stool consistency and gut microbiome.
- To compare PEG3350 effects with magnesium citrate and a vehicle control.
Main Methods:
- Mice received daily oral gavage of high/low dose PEG3350, magnesium citrate, or vehicle for two weeks.
- Laxative effectiveness was measured by weight and stool consistency.
- Anxiety-like behaviors were assessed using established behavioral tests (light/dark, open field, elevated plus maze).
- Gut microbiome analysis was performed on stool samples.
Main Results:
- Both PEG3350 and magnesium citrate altered stool consistency and gut microbiome diversity (alpha and beta diversity).
- No significant differences in anxiety-like behaviors were observed between PEG3350 treated groups and controls.
- Magnesium citrate also did not induce anxiety-like behaviors.
Conclusions:
- Daily PEG3350 administration in mice did not lead to anxiety-like behaviors.
- Changes in gut microbiome and stool consistency were observed but did not correlate with behavioral alterations.
- These findings suggest PEG3350 may not be a direct cause of anxiety-like behaviors in this model.
Objectives:
Polyethylene Glycol 3350 (PEG3350) is a laxative commonly used to treat constipation in children. The Food and Drug Administration has received reports of increased anxiety, aggression, and obsessive--compulsive behaviors in children administered PEG3350. Thus, we assessed whether daily administration of PEG3350 leads to anxiety-like behavior in mice.
Methods:
Outbred CD-1 IGS mice were administered either a high or a low dose of PEG3350 via daily oral gavage for 2 weeks. As a laxative comparison and control, additional mice were given a high or low dose of magnesium citrate or vehicle (water). Weight and stool consistency were assessed after each gavage to determine laxative effectiveness. Anxiety-like behaviors were assessed using light/dark, open field, and elevated plus maze (EPM) tests at baseline, after 2 weeks of daily gavage, and after a 2 week washout in experiment 1, and after 2 weeks of daily gavage in experiment 2. Stool samples were collected for microbiome analysis in experiment 2 at baseline, after 2 weeks of daily gavage, and after 2 weeks washout.
Results:
PEG3350 and magnesium citrate significantly changed stool consistency, as well as microbiome alpha and beta diversity. Anxiety-like behaviors were not, however, different in mice administered low or high doses of PEG3350 or magnesium citrate.
Conclusions:
Although changes in stool consistency and the gut microbiome occurred, administration of PEG3350 did not alter anxiety-like behaviors.
