Photoprotective and anti-inflammatory potential of polyphenol-rich extracts from agricultural by-products of chicory leaves, red onion peel, vineyard pruning, and olive pruning in UV-B-exposed 3D human skin equivalents

Abstract

Human skin equivalents (HSEs) serve as a robust model to evaluate the photoprotective effects of bioactive compounds. Polyphenols, known for their antioxidant, anti-inflammatory, and anti-aging properties, have emerged as promising agents for skin health applications in cosmetic industry. In this study, we evaluated the preventive effects of four polyphenolic extracts obtained from agricultural residues —chicory leaves, red onion peel, vineyard pruning, and olive pruning—on collagen metabolism, inflammation, and structural damage induced by UV-B radiation in HSEs. All extracts significantly reduced the presence of UV-B-induced sunburn cells (by 40–60 %, p < 0.001), modulated ECM components and pro-inflammatory pathways. Red onion peel and vineyard pruning extracts increased COL1α1 mRNA expression by 1.8- and 1.6-fold, respectively (p < 0.05), while the vineyard pruning extract significantly reduced IL6 expression by 50 % (p < 0.01), indicating anti-inflammatory properties. This study highlights the potential of polyphenolic extracts obtained from agricultural residues for skin photoprotection and anti-inflammatory, warranting further research is necessary to elucidate the underlying mechanisms of action.