Royal Jelly-Derived Extracellular Vesicles: Key Bioactive Components Mediating Anti-Hepatocellular Carcinoma Activity

To investigate the role of royal jelly derived extracellular vesicles (RJEVs) as key active components contributing to the anti-hepatocellular carcinoma (HCC) effects of royal jelly and to elucidate the underlying mechanisms.

This study used H22 tumor-bearing mice as an in vivo model. RJEVs were isolated and identified and their effects were evaluated after oral administration. Analyses included the assessment of liver-targeting properties, immune and antioxidant responses, gut microbiota composition (specifically Muribaculaceae abundance), and short-chain fatty acid metabolism. This study also examined the influence of RJEVs on translation-related signaling networks and the Phosphatidylinositol 3-kinase (PI3K) / Protein Kinase B (AKT) signaling pathway to determine their role in promoting tumor cell apoptosis.

Orally administered RJEVs exhibited liver-accumulating properties in H22 tumor-bearing mice and demonstrated moderate antitumor efficacy. They enhanced immune and antioxidant responses, increased the abundance of Muribaculaceae, modulated gut microbiota composition, and improved short-chain fatty acid metabolism. Mechanistically, RJEVs synergistically regulate translation-related signaling networks and remodel the immune microenvironment, ultimately promoting tumor cell apoptosis via the PI3K/AKT signaling pathway.

These findings provide novel insights into the functional role of royal jelly by identifying RJEVs as important bioactive constituents that contribute to the anti-HCC effects by modulating the immune microenvironment, gut microbiota, and PI3K/AKT signaling. This offers both theoretical and methodological advances in research on the bioactive components of bee products.