Role of luteolin extracted from Clerodendrum cyrtophyllum Turcz leaves in protecting HepG2 cells from TBHP-induced oxidative stress and its cytotoxicity, genotoxicity

• Main Authors: Gang Li, Jing Zhou, Mengyu Sun, Juren Cen, Jing Xu
• Format: Article
• Language: English
• Published: Elsevier 2020-11-01
• Series: Journal of Functional Foods
• Subjects: Luteolin; Cytotoxicity; Genotoxicity; Antioxidant; Oxidative stress
• Online Access: http://www.sciencedirect.com/science/article/pii/S1756464620304205

Luteolin derived from Clerodendrum cyrtophyllum Turcz leaves exhibited antioxidant activity. The IC50 values of luteolin for ABTS·+ and DPPH· free radical scavenging was 17.3 ± 0.82 μM and 13.2 ± 0.18 μM, respectively, and the compound showed better antioxidant activities than BHT (Butylated hydroxytoluene) and VC (Vitamin C). Luteolin exhibited neither cytotoxic nor promotional activities and no genotoxic effect toward HepG2 cells. The cell viability was significantly increased in a dose-dependent manner after preincubation of the cells with 1–40 μM luteolin followed by direct exposure to TBHP (tert-Butyl hydroperoxide). At the concentration of 30 μM, luteolin can reduce intercellular reactive oxygen species accumulation by 43.7 ± 3.98%, lactate dehydrogenase release by 38.7 ± 3.07% malondialdehyde levels by 24.5 ± 1.14% and increased 73.7 ± 6.04% superoxide dismutase activity and 72.3 ± 1.75% glutathione activity. A western blot assay showed that luteolin upregulated procaspase-3 and downregulated cleaved caspase-3 to counteract TBHP-triggered oxidative stress. Our study lays a theoretical foundation for the utilization and further development of luteolin as a promising natural antioxidant.