Figure 4.

Honey extracts protect HaCaT cells from UVB-induced protein oxidation. HaCaT cells were pre-incubated with 20 μg/mL of honey extracts and then were either exposed to UVB irradiation (55 mJ/cm²) or left untreated. Cells were treated for 2 h with honey extracts and then allowed to recover for 24 h. (a) Total antioxidant content and activity in HaCaT cell lysates was assessed by the ABTS oxidation assay and expressed as fold change in Trolox equivalents compared to untreated cells. (b) Protein oxidation was estimated by measuring the protein carbonyl levels with the DNPH colorimetric assay. The concentration of the protein carbonyls was determined and adjusted to the total protein concentration (expressed as fold-change compared to the untreated cells). Data shown are the mean ±SD of three independent experiments performed in triplicates. ## p ≤ 0.01, significant differences compared to untreated cells, * p ≤ 0.05, significant differences between UVB-irradiated and honey-treated/UVB-irradiated cells.