221. Alleviating effect of bioactive peptides in food on cognitive impairment

Abstract Background Cognitive impairment is a major global health challenge, but the existing drug treatment has limitations. Food derived bioactive peptides can maintain activity after digestion and have neuroprotective potential. The purpose of this study is to explore the alleviating effect of specific bioactive peptide mixtures prepared from soybean, milk and fish protein on cognitive function and pathological mechanism of Alzheimer's disease model mice. Methods This study used APP/PS1 transgenic mice and wild-type mice, divided into the following six groups: WT Con, WT-HP, Tg Model, Tg LP (50 mg/kg/day), Tg MP (100 mg/kg/day), and Tg HP (200 mg/kg/day). The active peptide was prepared by enzymatic hydrolysis of common food proteins and ultrafiltration. After 12 weeks of daily gavage intervention, cognitive function was evaluated by water maze test; The brain tissues were collected. ELISA, biochemical kit and qPCR were used to detect the levels of Aβ42, p-tau, oxidative stress indicators (SOD, GSH, MDA) and inflammatory factors (tnf- α, IL-1 β) in the hippocampus, and the morphology of neurons was observed. Data were statistically analyzed by ANOVA and Tukey test. Results The effects of different doses of bioactive peptides on hippocampal related indicators of APP/PS1 transgenic mice are shown in Table 1. It can be seen from table 1 that the behavioral test showed that medium and high dose peptide intervention significantly improved the learning and memory ability of model mice (p<.05 or p<.01). Biochemical tests showed that the intervention could dose dependently reduce Aβ42 deposition and tau protein phosphorylation in the hippocampus, and improve oxidative stress and inflammatory indicators. Nissl staining further confirmed that high-dose peptide effectively alleviated neuronal injury. Discussion This study confirmed that bioactive peptides from specific food sources can significantly improve the cognitive function of model mice, and the mechanism may be achieved through multiple targets: dose dependently reducing Aβ deposition and tau phosphorylation, enhancing antioxidant defense, and inhibiting neuroinflammation, so as to play a neuroprotective role. Funding No. 0202044242; No. ZG2503980051.