Research Paper Volume 11, Issue 1 pp 240—248

Metformin prolongs lifespan through remodeling the energy distribution strategy in silkworm, Bombyx mori

Jiangbo Song1,2, , Guihua Jiang1,2, , Jianfei Zhang1,2, , Jieshu Guo1,2, , Zheng Li1,2, , Kaige Hao1,2, , Lian Liu1,2, , Zilin Cheng1,2, , Xiaoling Tong1,2, , Fangyin Dai1,2, ,

  • 1 State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
  • 2 Key Laboratory for Sericulture Biology and Genetic Breeding, Ministry of Agriculture, College of Biotechnology, Southwest University, Chongqing 400716, China
* Equal contribution

Received: October 29, 2018       Accepted: December 26, 2018       Published: January 13, 2019
How to Cite

Copyright: © 2019 Song 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.


Metformin is a hypoglycemic agent used clinically in the treatment of type 2 diabetics. In addition, metformin is being investigated as a potential geroprotector. Here, we investigated the effects of metformin silkworm lifespan and the underlying molecular pathways involved. We found that metformin prolonged the lifespan of the male silkworm without reducing body weight, which suggests metformin can increase lifespan through remodeling of the animal’s energy distribution strategy. Consistent with that idea, metformin reduced silk production and thus the energy devoted to that process. Metformin also increased fasting tolerance and levels of the antioxidant glutathione, and also activated an adenosine monophosphate-activated protein kinase-p53-forkhead box class O signaling pathway in silkworm. These results suggest that activity in this pathway may contribute to metformin-induced lifespan extension in silkworm by increasing stress resistance and antioxidative capacity while reducing energy output for silk product. The results also show that the silkworm is a potential useful animal model for evaluating the effects of small molecules with potential clinical utility.


TAME: Targeting Aging with Metformin; NIH: National Institutes of Health; FDA: Food and Drug Administration; AAAR: American Association for Aging Research; AMPK: adenosine monophosphate-activated protein kinase; FoxO: Forkhead Box class O; GSH: glutathione; L4D1: day 1 of the 4th instar larva; L5D1: day 1 of the 5th instar larva; P1: day 1 of pupa stage; M1: day 1 of adult stage.