Effect of Acer truncatum Seed Oil on Physiological Indicators and Intestinal Flora in Aging Drosophila melanogaster

The aim of this study was to explore the effect of Acer truncatum seed oil (ATO) on physiological indicators and the intestinal flora in aging Drosophila melanogaster. Wild-type D. melanogaster was cultured on a basal medium supplemented with 10, 20 or 40 g/kg ATO, and its behavioral changes such as lifespan, crawling ability, and olfactory memory and heat tolerance capacity were evaluated. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured. The midguts were collected to examine changes in gut microbiota composition by using 16S rRNA gene sequencing. Compared with the control group, the average lifespan of D. melanogasters in each ATO intervention group was significantly increased (P < 0.0001); the most pronounced antiaging effect was observed at 20 g/kg ATO, where the average lifespan was prolonged by 31%. In addition, the crawling ability, olfactory memory and heat tolerance capacity were improved, and the activities of SOD and GSH-Px were increased in the 20 g/kg ATO intervention group. Aging changed the composition and structure of the gut microbiota in D. melanogasters. The results of linear discriminant analysis effect size (LEfSe) analysis suggested that the relative abundance of Enterobacteriaceae, Gluconobacter and Morganella morganii were increased in aging D. melanogasters, which was inhibited by ATO supplementation. To summarize, ATO has an anti-aging effect, alleviates physiological decline in D. melanogaster and prolongs its lifespan. The underlying mechanism may be related to changing the richness, evenness and structure of the gut microbiota in aging D. melanogasters, thereby regulating the gut microbiota and improving the antioxidant capacity.