Peptides of corn oligopeptides improve Aβ1-42-injured SHSY5Y cells.

BACKGROUND: There are more and more Alzheimer's patients. The formation of plaques of Aβ1-42 in the brain is one of the main causes of Alzheimer's disease. Corn oligopeptides have natural antioxidant effects. It is aimed to develop functional corn oligopeptides to prevent Alzheimer's disease through antioxidation.

METHODS: According to previous laboratory studies, peptides of corn oligopeptides were screened by biological activity score and ADMET prediction, and molecular docking technology was used to screen the peptides that had high binding energy with Aβ1-42. The protective effects of the selected peptides were evaluated against oxidative stress in Aβ1-42-injured SHSY5Y cells, and the mechanism of the effects in the protein kinase A (PKA)/cAMP-response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF)-mediated signaling pathway was investigated, which is closely related to neurodegenerative and neurological diseases.

RESULTS: The results showed that three peptides (GL, FA and FQ) significantly increased the cell viability of Aβ1-42-induced cells and mitochondrial intensity and decreased extracellular lactate dehydrogenase content. They also improved intracellular oxidative stress caused by Aβ1-42, including reducing the overproduction of intracellular reactive oxygen species, and increasing the content of lipid oxidation, superoxide dismutase and glutathione peroxidase. In addition, western blot showed that treatment with GL, FA and FQ significantly increased the expression of PKA, CREB and BDNF, whereas cells injured with Aβ1-42 decreased the expression of these signaling proteins.

CONCLUSION: These results suggest that peptides of corn oligopeptides can effectively improve Aβ1-42-induced Alzheimer's disease, and may improve oxidative stress response to protective nerve cells by up-regulating the protein expression of the PKA/CREB/BDNF signaling pathway. © 2025 Society of Chemical Industry.