Transplantation of gut microbiota from aged hosts was shown to have beneficial effects in young recipient mice lacking indigenous microbiota by an international team of scientists from Singapore, China, Australia and United Kindom led by Professor Parag Kundu, who recently joined The Center for Microbes, Development and Health at the Institut Pasteur of Shanghai (China) and Professor Sven Pettersson (NTU, Singapore). This study was reported on the November 13th, issue of Science Translational Medicine.
Our gut microbiota evolves continuously as we age while integrating environmental and host intrinsic signals. Such changes in the gut microbiota have been observed in humans as well as in experimental animals. However, the impact of these ageing associated changes in gut microbial communities on host physiology is not clearly understood. In an unique attempt to understand the influence of microbiota on host ageing, these researchers transplanted gut microbiota from old donor mice into young germ free recipient mice. Unexpectedly, they found microbiota from aged donors promotes intestinal growth, neurogenesis in the brain and prolongevity signalling in the young recipients. Microbiome analysis in the young recipients revealed enrichment in the population of microbes producing butyrate, a type of short chain fatty acid. Finally, the group confirmed the role of butyrate by treating sodium butyrate to young mice, which recapitulated the phenotypic changes observed in the young recipients transplanted with old donor microbiota. The results obtained in this study disclose the unique abilities that our gut microbiota possesses to support its eukaryotic counterpart during ageing.
The study marks a significant conceptual advancement in our understanding of the role of gut microbiota in host ageing process. These surprising findings hold future for the development of diet or microbiota-based intervention regimens to stimulate our gut microbiota and support metabolic homeostasis during ageing.
Legend: Microbiota transplants (MT) from young or old mice were performed into germ-free young recipient mice (left panel). Representative images of doublecortin stained neurons in the dentate gyrus of young recipient mice receiving microbiota transplant from young or old donors (right panels). Doublecortin staining is shown in red and DAPI counterstain is blue. The white arrows indicate doublecortin positive neurons and the red boxes indicate area that had been magnified. Scale bars, 100 μm. Kundu et al Science Translational Medicine 2019