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Can antibiotic treatment in preweaning rats alter body composition in adulthood?
Fanny B Morel1, Annemarie Oosting, Hugues Piloquet
1INRA-UMR 1280 Physiologie des adaptations nutritionnelles, Nantes, France.
Insights
Early-life antibiotic exposure, specifically amoxicillin, did not program adult body composition or obesity risk in rats. This study found no long-term effects on growth or body weight despite temporary changes in gut microbiota and food intake.
Area of Science:
- Developmental programming
- Microbiome research
- Obesity research
Background:
- Antibiotic use in infancy is hypothesized to influence adult body composition and obesity risk.
- This hypothesis is plausible due to antibiotics' impact on the developing intestinal microbiota.
- The gut microbiota plays a role in fat development and appetite regulation.
Purpose of the Study:
- To investigate the impact of neonatal amoxicillin treatment on rat growth and body composition.
- To determine if early-life antibiotic exposure programs adult body composition.
Main Methods:
- Neonatal rats received amoxicillin or vehicle via oral gavage from postnatal day 5 to 15.
- Growth, food intake, body composition, and plasma leptin were measured until postnatal day 130.
- Faecal microbiota composition was analyzed using real-time quantitative polymerase chain reaction.
Main Results:
- Amoxicillin altered faecal microbiota composition at postnatal day 21, but this effect was not sustained.
- A transient increase in food intake was observed in amoxicillin-treated rats immediately after weaning.
- No significant differences in growth or adult body composition were found between groups.
Conclusions:
- Neonatal amoxicillin treatment in rats does not lead to programming of adult body weight or composition.
- The study found no evidence supporting a link between early-life wide-spectrum antibiotic exposure and long-term obesity risk in this model.
Background:
It is suggested that antibiotherapy in infancy might program adult body composition and thus could be a determinant of obesity risk. Although not convincingly substantiated by existing literature, this assumption is plausible since antibiotics affect intestinal microbiota, whose composition in adulthood is potentially programmable during infancy and which is able to interact with both fat development and central control of appetite.
Objectives:
In order to substantiate the link between antibiotherapy and programming of adult body composition, the present study investigated the impact of a course of amoxicillin treatment in neonatal period on subsequent growth and body composition in rats.
Methods:
Suckling rat pups were treated by oral gavage with an amoxicillin solution (150 mg·kg(-1)) or vehicle from postnatal day (PND)5 to PND15. All animals were fully weaned at PND21 then fed a standard diet until PND130. Animal growth and food intake were followed up until PND130, when body composition and plasma leptin were measured. Faecal microbiota was typified at regular intervals using real-time quantitative polymerase chain reaction.
Results:
Preweaning amoxicillin treatment affected the composition of the faecal microbiota of pups at PND21 but this impact did not sustain long beyond the antibiotic supplementation. Immediately after weaning, a transient increase in food intake (+11%) was noticed in amoxicillin-treated animals. However, no significant impact on either growth or body composition at adulthood was observed.
Conclusions:
In a neonatal animal model there is no evidence of a programming of adult body weight and composition by wide-spectrum antibiotic treatment in early life.
