Ethyl Acetate Fraction of Abelmoschus manihot (L.) Medic Flowers Exerts Inhibitory Effects Against Oxidative Stress in H2O2-Induced HepG2 Cells and D-Galactose-Induced Aging Mice

Oxidative stress has been demonstrated to be associated with numerous aging-related diseases. Ethyl acetate fraction of Abelmoschus manihot (L.) Medic (EA) had been reported to possess strong radical-scavenging activity due to its rich content of flavonoids. This work aimed to determine the protective effects of EA against oxidative injuries in vivo and in vitro, as well as to explore the relevant mechanisms behind these effects. Pretreatment with EA significantly elevated cell viability of H2O2-induced HepG2 cells, reduced the reactive oxygen species level, decreased apoptotic cells, and inhibited activities of caspase 3/9. Meanwhile, EA pretreatment elevated the levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), while reduced malondialdehyde (MDA) generation and lactate dehydrogenase (LDH) release dose-dependently. In addition, EA modulated key marker genes expression of antioxidation and apoptosis-related signaling pathways at the messenger RNA (mRNA) and protein levels. In the animal studies, EA also significantly enhanced the antioxidant activity and reduced MDA generation in serum, liver, and brain of the D-galactose (D-gal)-induced mice. Furthermore, the histological analysis indicated that EA effectively alleviated liver and brain injury of mice induced by D-gal, dose-dependently. EA as a potential antioxidant agent promoted health and reduced the risk of aging-associated diseases.

Automated summary

This study demonstrated that EA has significant protective effects against oxidative injuries, reducing cell apoptosis caused by oxidative stress and protecting the body from oxidative damage by modulating relevant signal pathways and gene expression. Animal experiments also confirmed the effectiveness of EA in combating oxidative damage, suggesting its potential as an antioxidant agent for preventing aging-related diseases.