Neuroprotective and antioxidant effects of Metasequoia glyptostroboides leaf extract

Abstract

Extracts from the leaves of Metasequoia glyptostroboides (M. glyptostroboides) were investigated for antioxidant and neuroprotective effects in an attempt to further the development of novel pharmaceuticals. We demonstrated the antioxidant activities of these extracts using multiple methods, including the 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazoliumbromide cell viability and malondialdehyde assays; 2', 7'-dichlorofluorescein diacetate (DCF-DA) was used to detect and measure reactive oxygen species (ROS). These extracts effectively inhibited hydrogen peroxide-induced lipid peroxidation in neuronal PC12 cells by reducing intracellular ROS accumulation. High-performance liquid chromatography analysis revealed these extracts to contain a variety of known compounds (including rutin, quercitrin, myricetin, quercetin, kaempferol, gallic acid, epigallocatechin, epigallocatechin gallate, caffeic acid, and epicatechin gallate) in varying amounts. The extracts from M. glyptostroboides leaves exhibited a similar (and in some cases, more favorable) biological activity to that of ascorbic acid. The findings of this study suggested that M. glyptostroboides leaves have the potential to protect against hydrogen peroxide-induced damage and should be considered as a prospective functional food.