Martin Blaser’s lab showed a few years ago that exposing mice to low doses of antibiotics very early in their lives changes their gut microbiota and makes the mice gain more fat and gain more body weight later in life. Jonas Schluter and I started collaborating with Blaser’s group three years ago.  In a paper published today in the ISMEJ we analyzed one of their latest experiments–one with a large scale cohousing scheme that sought to determine whether exchanging gut microbes with untreated mice would lower the tendency that antibiotic-exposed mice to had to gain more weight.

We saw that mice exposed to antibiotics in early life mice got on a weight-gain trajectory, and they stayed on that trajectory despite exchanging microbes with mice who were never exposed to antibiotics.  We ran many statistical tests as part of our analysis. The paper shows that the effect of antibiotics is reproducible and robust.

Our paper has implication for obesity in people too. We are frequently exposed to low doses of antibiotics that could cause us to gain more weight. The impact of antibiotics is robust, and reversing the propensity to gain weight may not be solved simply by borrowing excrement from someone else to do a fecal microbiota transplant, appealing as that may sound.

Read the paper: The impact of early-life sub-therapeutic antibiotic treatment (STAT) on excessive weight is robust despite transfer of intestinal microbes.
Anjelique F. Schulfer, Jonas Schluter, Yilong Zhang, Quincy Brown, Wimal Pathmasiri, Susan McRitchie, Susan Sumner, Huilin Li, Joao B. Xavier & Martin J. Blaser. ISMEJ
[Open access]