This
web page was produced as an assignment for an undergraduate course at
Davidson College.
Julia Preziosi
"Lactobacillus
plantarum strain maintains growth
of infant mice during chronic undernutrition"
A
Review
Summary:
This paper (Schwarzer et al.
2016) explores the effects of gut microbiota on nutrition-dependent
growth of infant mice. Specifically, the team investigates what impacts
the presence and absence of L.
plantarum strains have in promoting the growth of juvenile
mice. They deduce that the bacterium interacts with growth-related
hormones in the somatropic axis to allow weight and length growth in
germ-free mice comparable to that of wild type mice in both normal
breeding diets and nutrient depleted diets. They connect these
physiological growth responses to changes in Growth Hormone (GH) and
Insulin-Like Growth Factor-1 (IGF-1), and make the claim that the
microbiota directly promotes growth by facilitating production and
activity of these biological products.
Review:
While this paper
investigates an interesting phenomenon of the microbiota's role in
growth, it takes what starts as a discovery science paper and develops
it into a validation science paper, by the use of the researchers'
previously known bacterial strain, L.
plantarum, which they had seen to function similarly in
Drosphila. By doing so, the investigators limit their findings
to validation, instead of looking for any other bacteria that might also
impact this response. They didn't look into what bacterial populations
were present in the mouse gut naturally, or investigate if other
bacteria also caused similar GH and IGF-1 responses. I feel as though
the investigators were not doing their responsibility as scientists to
take an honest look at a system and explore seemingly unpredicted data,
and instead chose to focus only on the data that would validate the idea
that they had before beginning investigation. They also conclude that
microbial interventions could buffer the adverse effects of
undernutrition; however, the microbial interventions would just be
towards a typical microbiome (WT mice) instead of no microbiome (GF), as
the addition of an exclusively L. plantarum microbiome didn't improve
from the WT condition experiencing undernutrition. The real best way to
combat undernutrition is with increased nutrition.
Reference:
Schwarzer M et al. 2016. Lactobacillus plantarum strain maintains growth of infant mice during chronic undernutrition. Science, vol 351 issue 6275 854-857
Email Questions or Comments: jupreziosi@davidson.edu
© Copyright 2016 Department of Biology, Davidson College, Davidson, NC 28035