The Immunomodulatory Effects of Royal Jelly on Defending Against Bacterial Infections in theCaenorhabditis elegansModel

Emerging evidence suggests that aging is associated with the deterioration of immunity, a term known as immunosenescence, which may lead to a higher incidence of infections in the elderly population. Our previous studies reported that supplementation of royal jelly (RJ) extended the lifespan ofCaenorhabditis elegans(C. elegans), a nematode model. The aim of this study was to investigate the potential benefits of RJ supplementation on modulation of the innate immunity inC. elegans. UsingStaphylococcus aureus(S. aureus; ATCC 25923) as the infection model, we showed that RJ supplementation from the egg hatching stage could protectC. elegansagainst the infection. Further mechanistic studies demonstrated that RJ coordinated pathways of IIS/DAF-16, p38 MAPK, and Wnt to modulate the innate immunity. In addition, when RJ was administrated to the agedC. elegans, the worms displayed prolonged survival time to a variety of bacterial infections compared with the nontreatment group. This result indicates the RJ may help delay the innate immunosenescence.