Research Paper Volume 11, Issue 13 pp 4611—4640
The role of commensal microbes in the lifespan of Drosophila melanogaster
- 1 Department of Biological Sciences, Inha University, Incheon 22212, South Korea
- 2 School of Biological Sciences, Seoul National University, Seoul 08826, South Korea
Received: January 29, 2019 Accepted: June 28, 2019 Published: July 12, 2019https://doi.org/10.18632/aging.102073
How to Cite
Copyright: Lee et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Commensal microbes have mutualistic relationships with their host and mainly live in the host intestine. There are many studies on the relationships between commensal microbes and host physiology. However, there are inconsistent results on the effects of commensal microbes on host lifespan. To clarify this controversy, we generated axenic flies by using two controlled methods – bleaching and antibiotic treatment – and investigated the relationship between the commensal microbes and host lifespan in Drosophila melanogaster. The removal of microbes by using bleaching and antibiotic treatments without detrimental effects increased fly lifespan. Furthermore, a strain of flies colonized with a high load of microbiota showed a greater effect on lifespan extension when the microbes were eliminated, suggesting that commensal bacteria abundance may be a critical determinant of host lifespan. Consistent with those observations, microbial flora of aged fly gut significantly decreased axenic fly lifespan via an increase in bacterial load rather than through a change of bacterial composition. Our elaborately controlled experiments showed that the elimination of commensal microbes without detrimental side effects increased fly lifespan, and that bacterial load was a significant determinant of lifespan. Furthermore, our results indicate the presence of a deterministic connection between commensal microbes and host lifespan.