LAUSR

Description Lactiplantibacillus plantarum promotes growth in undernourished mice Undernutrition is a leading cause of infant and childhood mortality (1). Undernutrition not only has an impact on growth and development but also leads to impaired gut microbiota development. The transfer of gut microbiota from undernourished children to germ-free mice drives growth stunting and reduced weight, whereas mice on the identical diet but colonized with healthy children’s microbiota grow normally (2). However, the mechanisms by which gut microbes contribute to postnatal growth are not clear. On page 826 of this issue, Schwarzer et al. (3) report that supplementation of undernourished mice with Lactiplantibacillus plantarum strain LpWJL improves systemic growth and weight gain. Notably, they find that the growth-promoting effect of LpWJL is mediated through bacterial peptidoglycan ligands that trigger the activation of nucleotide-binding oligomerization domain–containing protein 2 (NOD2)—an innate immune receptor that is usually associated with host defense and intestinal homeostasis—in intestinal epithelial cells.