Photochemoprotective effects against UVA and UVB irradiation and photosafety assessment of Litchi chinensis leaves extract

Abstract

Actually, there has been an increase in the use of natural products as skin photoprotective agents. In this way, the aim of present study was to investigate the L. chinensis leaves extract photochemoprotection potential and photosafety using in vitro methods. The extract cytotoxicity, cytoprotection and photochemoprotection against UVA and UVB radiation were assayed in L929 cells. The DNA damage was evaluated by comet assay. DCFH-DA, SOD, CAT and GSH assays were employed to verify the oxidative stress. We also determined the spectrophotometric Solar Protection Factor (SPF) of the extract. The photosafety was evaluated in red blood cells (RBC). In addition, the HET-CAM and agarose overlay tests were employed to evaluate the irritant potential. The results obtained show that extract is not cytotoxic and present cytoprotective activity against H₂O₂ and is able to protect the cells against DNA damage induced by UVA and UVB radiation. The extract was able to reduce the ROS production. The SPF obtained was 18.9 at 1mg/mL. We demonstrate that L. chinensis extract is photosafe and protect RBCs against oxidative damage, and did not induce irritation. Data herein obtained pointed out the potential of L. chinensis extract for photochemoprotection against UVA/UVB radiation and its damaging effects on human skin.

Keywords: Irritant; Litchi chinensis; Photochemoprotection; Photohaemolysis; Phototoxicity.