Investigating Antioxidant and Anti-aging Properties of Katsuwonus pelamis Peptides in Drosophila Subjected to High-Fat Diets

This study investigates the antioxidant and anti-aging properties of Katsuwonus pelamis peptides (KPPs) using a high-fat diet (HFD) Drosophila melanogaster model. In vitro analysis revealed KPPs exhibit potent radical scavenging activity (e.g., DPPH IC₅₀ = 1.80 mg/mL). In HFD-fed flies, KPPs supplementation significantly extended median lifespan by 23.4% (P < 0.01) and improved motor function (e.g., climbing index increased by 30.0%). In the model, KPPs significantly prolonged lifespan, improved motor function, lowered peroxide, malondialdehyde (MDA) levels, and triglyceride content. Concurrently, KPPs enhanced antioxidant enzyme activity, increasing T-SOD by 20.9% and GSH-Px by 80.1%. Furthermore, KPPs attenuated aging by upregulating key antioxidant genes (Sod1, Cat) and inhibiting the insulin/IGF-like signaling (IIS) pathway. KPPs also demonstrated significant intestinal protection: reducing lipid droplet accumulation and ROS levels, decreasing apoptosis in epithelial cells by 43.2%, while suppressing intestinal stem cell proliferation. These effects collectively preserved gut integrity, maintained homeostasis, and contributed to delayed aging. This study provides compelling evidence for KPPs as a novel intervention to counteract HFD-induced damage and mitigate aging processes.