Cyanidin-3-O-Glucoside Mitigates Amyloid-Beta (1–42)-Induced Apoptosis in SH-SY5Y Cells by Regulating Ca2+ Homeostasis and Inhibiting Mitochondrial Dysfunction

Background: Blueberry anthocyanin such as Cyanidin-3-O-glucoside may help prevent Alzheimer’s disease. We aimed to investigate the preventive and therapeutic effects of Cyanidin-3-O-glucoside against Aβ1–42-induced apoptosis of SH-SY5Y cells as well as the underlying mechanisms. Methods: Cell viability and intracellular and mitochondrial reactive oxygen species were detected by MTT, a reactive oxygen species detection kit, and a MitoSOX red mitochondrial superoxide indicator. The mitochondrial membrane potential, intracellular calcium ion content, and adenotriphophate (ATP) were identified via a mitochondrial membrane potential detection kit, calcium ion detection kit, and ATP detection kit, and apoptosis was detected via flow cytometry. Transcription of apoptosis-related genes was detected using real-time fluorescence quantitative polymerase chain reaction, and expression of apoptosis-related proteins was identified using Western blot. Results: We found that Cyanidin-3-O-glucoside could downregulate the expression of cytochrome c, caspase 9, caspase 3, and other genes and proteins, which consequently reduced the rate of apoptosis. Additionally, it could upregulate Bcl-2 gene and protein expression, downregulate Bax gene and protein expression, regulate mitochondrial membrane permeability and calcium-release channels, reduce calcium influx into mitochondria, maintain intracellular calcium ion levels, reduce intracellular levels of reactive oxygen species and increase ATP levels, maintain the mitochondrial membrane potential at a normal level, maintain normal mitochondrial functioning, and prevent apoptosis. Discussion: Taken together, Cyanidin-3-O-glucoside showed dose-dependent preventive and therapeutic effects against Aβ1–42-induced apoptosis of SH-SY5Y cells. Conclusions: Cyanidin 3-O-glucoside showed a better preventive effect than therapeutic effect against Aβ1–42-induced apoptosis in SH-SY5Y cells.