Spermidine alleviates oxidative stress in silk glands of Bombyx mori

Silk gland is a specialized organ for the synthesis of silk. Spermidine is a natural polyamine present in all living cells. It gained attention recently due to its role in longevity and growth promotion. Our earlier study reported enhancement in silk production after spermidine treatment during the 5th instar larval stage of Bombyx mori hybrid strain CSR2 x CSR4. Oxidative stress increases during the degeneration of silk glands in spinning stage. Spermidine plays an important role in relieving oxidative stress. Results showed that exogenous administration of natural poly amine, spermidine, significantly increased the metabolic activity and reduced the oxidative stress of the silk gland in the pre-pupal stage. Expression analysis also confirmed increase in metabolic activity of silk glands after spermidine treatment by showing enhancement in MYC gene expression. Finally, our results demonstrate that supplementation of spermidine enhanced cell viability and decreased oxidative stress of the silk glands. This work also opens up the idea of feeding antioxidants to silkworms which would be beneficial to the sericulture farmers. (C) 2016 Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society. Published by Elsevier B.V. All rights reserved.