Effect of Hedyotis diffusa water extract on protecting human hepatocyte cells (LO2) from H2O2-induced cytotoxicity

AbstractContext: Natural products are good sources of natural dietary antioxidants that are believed to protect the body against hepatotoxic effect induced by oxidative stress. Hedyotis diffusa Willd (Rubiaceae) (HDW) is a traditional Chinese medicinal herb that has been shown to possess a variety of antioxidant properties.Objective: The present study examines and explains the cell protective property of HDW water extract (WEHDW).Materials and methods: 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) assay was used to measure the free radical scavenging property of WEHDW (0.001–10 mg/mL). The protective effect of WEHDW (0.3–10 mg/mL 2 h pretreatment) against hydrogen peroxide (H2O2, 200 μM for 6 h) induced cytotoxicity in human hepatic cells, LO2, was evaluated using cell viability assay and nuclear staining. The molecular pathway of WEHDW's effect was investigated by using Western blot assay.Results: WEHDW had a 50% scavenging concentration (SC50) at 0.153 mg/mL in the DPPH assay. Exposure of LO2 ce...