Abstract: The protective effect of oligomolymeric procyanidins (LPOPC) and six monomeric procyanidins from litchi pericarp on ultraviolet B (UVB, 280–320 nm)-induced oxidative damage in HaCaT cells was evaluated in this study. UVB-damaged HaCaT cells were treated with para-aminobenzoic acid (PABA) as a positive control, LPOPC and the monomeric procyanidins, separately. Native and irradiated cells without drug treatment were used as a control group and a model group, respectively. Cell viability was detected by the CCK-8 method. The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were detected using commercial kits, and the levels of reactive oxygen species (ROS), glutathione (GSH) and malondialdehyde (MDA) were also measured. These results showed that LPOPC and the six monomeric compounds significantly increased the viability of HaCaT cells damaged by UVB, reduced the generation of intracellular ROS and MDA, increased the activities of SOD, CAT and GSH-Px and GSH levels. The protective effect of procyandin A2 against oxidative stress in HaCaT cells was the most significant among the six monomeric compounds, which was equivalent to that of PABA. Therefore, LPOPC and the monomeric compounds have a good protective effect on UVB-induced oxidative damage in HaCaT cells by enhancing intracellular antioxidant capacity and inhibiting lipid peroxidation. It is suggested that procyanidin A2 from litchi pericarp is an active component with the strongest protective effect.

Key words: procyandins from litchi pericarp; HaCaT cells; ultraviolet B radiation; oxidative stress-induced damage; protective effect