Enhanced Neuroprotective Effects of Epicatechin Gallate Encapsulated by Bovine Milk-Derived Exosomes against Parkinson’s Disease through Antiapoptosis and Antimitophagy

Epicatechin gallate (ECG) is a main effective catechin widely existing in natural plants and food, with well-known health benefits. The present study first designed a new exosome-based delivery system for ECG and examined its neuroprotective effects on a rotenone (Rot)-induced Parkinson's disease (PD) model in vitro. Exosomes (Exo) were isolated from fresh bovine milk, and their average size was 85.15 ± 2.00 nm. ECG was encapsulated into Exo by a sonication method, and the loading efficiency of ECG-loaded exosomes (ECG-Exo) was 25.96 ± 0.45%. The neuroprotective effects of ECG-Exo were evaluated on Rot-induced SHSY5Y cells and compared with free ECG. Cell viability, cellular reactive oxygen species, apoptosis rate, and the expressions of caspase-3, Bax, Bcl-2, parkin, PINK1, and Atg5 were determined. Our results showed that Exo delivered ECG successfully into SHSY5Y cells and exhibited enhanced neuroprotective effects. ECG-Exo might inhibit SHSY5Y cell damage induced by Rot through antiapoptosis and antimitophagy.