This study aimed to evaluate the positive effect of autumn olive berries (AOB) extract on aging delay by improving the lipid metabolism of middle-aged C. elegans who became obese due to high glucose (GLU) diet. As a result of investigating the total phenol content and DPPH radical scavenging ability of freeze- or spray-dried AOB, freeze-dried AOB showed better antioxidant potential. Afterward, through HPLC analysis, it was confirmed that catechin was the main compound in the polyphenols of AOB. Therefore, we used freeze-dried AOB in subsequent in vivo experiments. AOB inhibited lipid accumulation in both the young adult and middle-aged groups in a concentration-dependent manner under both normal and 2% GLU conditions. Additionally, AOB inhibited ROS accumulation in a concentration-dependent manner under normal and 2% GLU conditions in the middle-aged worms. In particular, AOB also increased the number of body bending and egg production in middle-aged worms. To confirm the intervention of genetic factors related to lipid metabolism in the effect of AOB, body lipid accumulation was confirmed using worms deficient in the daf-16, atgl-1, aak-1, and akt-1. Regarding the effect of AOB on reducing lipid accumulation, the impact was nullified in daf-16 deficient worms under the 2% GLU condition and nullified in both daf-16 and deficient worms under fasting conditions. This means that AOB regulates lipogenesis and lipolysis by mediating daf-16 and atgl-1 in middle-aged worms. Our results suggest that AOB contributes to the aging delay effect by improving lipid metabolism in metabolic impaired middle-aged worms.
