Photodamage attenuating potential of Nectandra hihua against UVB-induced oxidative stress in L929 fibroblasts

Publication date: Available online 9 March 2018
Source:Journal of Photochemistry and Photobiology B: Biology
Author(s): Mariana Maciel de Oliveira, Regina Gomes Daré, Érica Oliveira Barizão, Jesuí Vergílio Visentainer, Mariza Barion Romagnolo, Celso Vataru Nakamura, Maria da Conceição Torrado Truiti
The total phenolic content (TP) and antioxidant activity of the ethanolic extract and fractions that were obtained from the leaves of Nectandra hihua were assessed using different assays. The ethanolic extract (EE) and ethyl acetate fraction (EAF) had the best antioxidant capacity, which was comparable to butylated hydroxytoluene and quercetin (ABTS⁺ 2.55 ± 0.06, 3.54 ± 0.03 mmol TE/g; DPPH IC50 10.27 ± 0.05, 9.88 ± 0.02 μg/mL; FRAP 2.17 ± 0.08, 2.38 ± 0.04 mmol TE/g; ORAC 5.16 ± 0.08, 5.35 ± 0.07 mmol TE/g; TP 568.05 ± 18.15, 397.20 ± 17.88 mg GAE/g, respectively). The cytoprotective effect, reactive oxygen species (ROS) and lipid peroxidation inhibitions on L929 fibroblasts irradiated with UVB (600 mJ/cm²) in pre- and post-treatments with EE and EAF were determined. These plant materials demonstrated high ROS scavenging activity and lipid peroxidation inhibition on L929 fibroblasts in both treatments, especially with pre-treatment (EE 38.47 ± 1.95% and EAF 40.20 ± 4.5% inhibition of ROS production, and EE 39.03 ± 3.33% and EAF 41.67 ± 7.6% of lipid peroxidation inhibition), indicating the best cytoprotection with pre-treatment (13.52 ± 1.66% and 13.34 ± 2.61% increases in cell viability). The antioxidant flavonoids quercitrin, avicularin, juglalin, afzelin and astragalin were isolated from EAF. The results obtained indicate that EE and EAF present photodamage attenuating potential against UVB-induced oxidative stress and can be useful as a starting point for developing dermatological products to prevent oxidative skin damage.