Moderate dietary restriction across generations promotes sustained health and extends lifespan by enhancing antioxidant capacity in Bombyx mori

Moderate dietary restriction (DR) is known to extend lifespan, but its long-term safety remains unclear. In this study, silkworms of P50 were divided into libitum feeding (AL) and DR groups, with the DR group receiving 65% of the AL group's intake. Using the contemporary DR cohort as the parent generation, the identical dietary restriction methodology is perpetuated across successive generations to establish a multi-generational DR model. We recorded body weight, lifespan, spawning amount, and cocoon shell rate at each generation, and analyzed tissue sections of the G6 generation. Biochemical indices of hemolymph were assessed in the G0 and G3 generations, and the expression levels of genes associated with DR metabolism were analyzed using quantitative PCR. The result showed that DR initially caused weight loss, which then stabilized, and significantly extended lifespan. Biochemical indicators showed that silkworm's antioxidant capacity improved significantly in DR group, with notable differences between the current (G0) and successive (G3) generations. Gene expression related to oxidative stress was significantly altered depending on there function in G3 compared to G0. This suggests that long-term moderate DR can extend lifespan and reduce weight and fat, mainly due to enhanced antioxidant capacity. Additionally, animals demonstrated adaptability to prolonged moderate DR, indicating its feasibility across generations in insects. Our study confirms that boosting antioxidant capacity is a healthy, life-extending strategy under dietary restriction and highlights the adaptability of animals to such diets over generations, supporting the development of safe, long-term dietary plans for humans and large animals.