Abstract
Squalane, a highly stable derivative of squalene, has received attention for its potential application in dermatology and cosmetics due to its biocompatibility, moisturizing properties, and antioxidant activity. This study investigates the effects of squalane on UVA-induced oxidative stress, inflammation, deregulation of collagen metabolism, and some growth signaling pathways in human dermal fibroblasts (HDFs). It has been found that squalane at concentrations of 0.005-0.015% counteracted the UVA-induced inhibition of oxidative stress, collagen biosynthesis, prolidase activity, expression of the β1-integrin receptor, insulin-like growth factor-I receptor (IGFR), transforming growth factor-β (TGF-β), phosphorylated kinases ERK1/2, and increase in the expression of p38 kinase in HDFs. Moreover, squalane at the studied concentrations counteracted UVA-induced increase in the expression of NF-κB and COX-2 in HDFs, suggesting its anti-inflammatory activity. Interestingly, squalane augmented the UVA-induced expression of nuclear factor erythroid 2-related factor 2 (Nrf2). The functional significance of squalane activities was found in a model of wound healing in HDFs. Squalane at the studied concentrations stimulated fibroblast migration, facilitating the repair process following exposure of the cells to UVA radiation. These results demonstrate the ability of squalane to counteract UVA-induced cell damage and suggest its potential to support skin regeneration, highlighting its application in anti-aging, post-sun repair, and regenerative care formulations.