The diet of pregnant mice influences their offspring’s metabolism. This can affect the likelihood for their progeny to develop diabetes or become overweight as adults. A Japanese group of researchers published these results on February 28, 2020, in the journal Science.
The scientists fed one group of mice a diet that was high in fiber, one group a diet that was low in fiber, and gave antibiotics to the third group, to kill their gut microbes. They found that the offspring of the low fiber diet- and germ-free mice had more metabolic problems and a higher chance to become obese (on a high fat diet) than the offspring of the mice that were fed a fiber rich diet.
When animals and humans consume fiber, gut microbes ferment these to short chain fatty acids (SCFAs), which have a number of beneficial functions. SCFAs can be ingested and enter the blood, where they reduce appetite and affect cardio-metabolic health and reduce the amount of fat that is stored in fat cells. This is beneficial for both, mouse, and human health.
Short chain fatty acids reach embryos via placenta
The researchers of the Japanese study showed that SCFAs are transferred from the mother’s blood to the offspring, where they influence metabolic development. Fetuses of low fiber diet or germ-free mice had problems developing hormone producing cells in the gut, as well as pancreas cells. These cells are needed for insulin secretion; otherwise blood-glucose levels are not regulated correctly. If both cell types are not fully developed in the fetus, the adult mouse will have metabolic problems.
These negative effects could be prevented, when low fiber fed, or germ-free mice received SCFA supplements. Their offspring had a similarly low likelihood to become overweight as the offspring of mice that had been on a high fiber diet during pregnancy. This shows how crucial the SCFAs are.
Mice, like other animals, are good models to study human development and disease (also explained here). Therefore, the study hints toward the importance of a high fiber diet for pregnant women.
Kimura, I., Miyamoto, J., Ohue-Kitano, R., Watanabe, K., Yamada, T., Onuki, M., … & Inaba, A. (2020). Maternal gut microbiota in pregnancy influences offspring metabolic phenotype in mice. Science, 367(6481).