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Effect of antibiotic treatment on intestinal microbial and enzymatic development in postnatally overfed obese rats
Štefan Mozeš1, Zuzana Šefcíková, Dobroslava Bujnáková
1Department of Developmental Physiology, Institute of Animal Physiology, Slovak Academy of Sciences, Šoltésovej 4-6, 040 01 Košice, Slovak Republic. mozes@saske.sk
Insights
Early life overfeeding in rats led to increased gut bacteria Lactobacillus/Enterococcus (LAB) and decreased Bacteroides/Prevotella (BAC), contributing to later obesity risk. These changes persisted despite antibiotic treatment.
Area of Science:
- Microbiology
- Developmental Biology
- Nutritional Science
Background:
- Early life nutrition significantly impacts long-term health outcomes.
- Gut microbiota plays a crucial role in host metabolism and development.
- Overfeeding during sensitive developmental periods can have lasting consequences.
Purpose of the Study:
- To investigate the effects of early overfeeding and amoxicillin on gut microbiota and obesity in Sprague-Dawley rats.
- To assess the impact of litter size-induced overfeeding on intestinal microbial and functional adaptability.
- To determine the long-term consequences of early life nutritional status on obesity development.
Main Methods:
- Rats were assigned to small litters (SLs, 4 pups) or normal litters (NLs, 10 pups) to induce differential nutrition.
- Gut microbial populations (Bacteroides/Prevotella (BAC) and Lactobacillus/Enterococcus (LAB)) were quantified using fluorescence in situ hybridization.
- Intestinal enzyme activities (alkaline phosphatase, α-glucosidase, aminopeptidase) were analyzed histochemically.
Main Results:
- Small litter (overfed) rats exhibited greater weight and fat gain, with higher LAB and lower BAC counts compared to normal litter rats.
- Elevated alkaline phosphatase activity was observed in overfed rats and persisted over time.
- Amoxicillin treatment reduced LAB and BAC quantities but did not alter the obesity-related changes induced by overfeeding.
Conclusions:
- Early life overfeeding profoundly influences gut microbial composition and function during development.
- These microbiota-induced changes are linked to an increased risk of developing obesity later in life.
- The study highlights the critical window of early nutrition for establishing gut health and preventing metabolic disorders.
Objective:
To investigate the effect of the microbiota-induced changes and early overfeeding after amoxicillin administration (a) in suckling pups via their dams up to 15 days of lactation and (b) in weaned pups on intestinal microbial/functional adaptability and obesity development in male Sprague-Dawley rats.
Design And Methods:
Postnatal nutrition was elicited by adjusting the number of pups in the nest to 4 (small litters [SLs]) and 10 (normal litters [NLs]), while from days 21 to 40, both groups were fed with a standard diet. The numbers of Bacteroides/Prevotella (BAC) and Lactobacillus/Enterococcus (LAB) in the jejunum and colon were determined by fluorescence in situ hybridization technique, and jejunal alkaline phosphatase (AP), α-glucosidase and aminopeptidase activity was assayed histochemically.
Results:
On day 40, the SL in comparison with NL animals displayed excess weight/fat gain accompanied by higher LAB and lower numbers of BAC, and with permanently higher AP activity. Moreover, these acquired changes continued in SL vs. NL rats and were not influenced by antibiotic treatment, which induced significant decrease in the quantity of LAB and BAC.
Conclusions:
These findings highlight the role of early life overfeeding upon the gut microbial/functional ontogeny and allow to distinguish their potential involvement in later risk of obesity.
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