Protective Effects of Deer Antler Peptides on D-Galactose-Induced Brain Injury

<b>Background/Objectives:</b> The aim of this study was to investigate the role and potential mechanism of deer antler peptides (DAP) in D-galactose (D-gal)-induced brain injury. <b>Methods:</b> In the in vivo study, C57BL/6J mice were intraperitoneally injected with 400 mg/kg D-gal and gavaged with DAP (50 and 200 mg/kg) for 5 weeks. In vitro studies, D-gal (30 μg/mL) induced senescent BV2 cells were used for further research. <b>Results:</b> DAP increased the expression of BDNF and VEGF in the brain tissue of aging mice, reduced the levels of oxidative stress and inflammatory factors in serum, and decreased the pathological damage of brain tissue. In vitro, DAP promoted the proliferation of D-gal-induced senescent BV2 cells, reduced ROS level, and inhibited the release of IL-1β, IL-6 and TNF-α. In addition, DAP significantly reduced the protein expressions of TLR4 and MyD88, and inhibited the phosphorylation of NF-κB. <b>Conclusions:</b> DAP can inhibit the TLR4/MyD88/NF-κB signaling pathway, reduce oxidative stress and inflammation, and promote neovascularization. This indicates the therapeutic potential of DAP as a natural bioactive substance in preventing aging-related brain injury.