Lonicera caerulea fruits reduce UVA-induced damage in hairless mice

• Effects of Lonicera caerulea berries (LCB) on UVA-induced damage were investigated.
• Mice received a diet with 10% of LCB for 2 weeks and were exposed to 30 J/cm2 of UVA.
• LCB reduced malondialdehyde levels and increased catalase activity and GSH levels.
• LCB reduced UVA-induced NQO1 and GCLm levels and enhanced HO-1 level in skin.
• LCB enhanced interleukin-17 and reduced interleukin-12 levels in plasma.

UVA photons are less energetic than UVB photons but they are more abundant in solar radiation. Modern tools have shown that UVA light has serious adverse effects on the skin. We investigated the effect of consuming Lonicera caerulea berries on UVA-induced damage in SKH-1 mice. The mice were fed a diet containing L. caerulea berries (10%, w/w) for 14 days before a single UVA (30 J/cm2) treatment. Effects on haematological and antioxidant parameters were evaluated 4 and 24 h after irradiation. The bioavailability of L. caerulea phenolics was also assessed. Consuming the L. caerulea berry-enriched diet caused reduced malondialdehyde production and increased catalase activity and glutathione levels were found in skin and erythrocytes. UVA-induced NADPH:quinone oxidoreductase-1 and gamma-L-glutamate-L-cysteine ligase protein in skin were reduced in mice fed L. caerulea berries. Enhanced heme oxygenase-1 level in skin, interleukin-17 in plasma and reduced interleukin-12 levels in plasma were found in the mice on the experimental diet. Histological (pyknotic) changes in the nuclei of basal cells induced by UVA exposure were reduced in L. caerulea berry consuming animals. HLPC-MS analysis showed high concentrations of hippuric acid, one of the main metabolites of aromatic amino acids and phenolic compounds, in skin, liver, urine and faeces of mice consuming the berries.Taken together, consumption of L. caerulea berries affords protection from the adverse effects of a single UVA exposure mainly via modulation of antioxidant parameters.