Claude Saliou

Role of vitamins in skin care.

Therapeutic (vitamins A and D, and their analogs) and antioxidant (vitamins C, E, and coenzyme Q) vitamins play an increasing role in skin care. Their benefits range from skin conditions such as acne and psoriasis to the protection against environmental insults.

Galvanic zinc–copper microparticles inhibit melanogenesis via multiple pigmentary pathways

The endogenous electrical field of human skin plays an important role in many skin functions. However, the biological effects and mechanism of action of externally applied electrical stimulation on skin remain unclear. Recent study showed that galvanic zinc–copper microparticles produce electrical stimulation and reduce inflammatory and immune responses in intact skin, suggesting the important role of electrical stimulation in non-wounded skin. The objective of this study is to investigate the biological effect of galvanic zinc–copper microparticles on skin pigmentation. Our findings showed that galvanic zinc–copper microparticles inhibited melanogenesis in a human melanoma cell line (MNT-1), human keratinocytes and melanoma cells co-cultures, and in pigmented epidermal equivalents. Treatment of galvanic zinc–copper microparticles inhibited melanogenesis by reducing the promoter transactivation of tyrosinase and tyrosinase-related protein-1 in human melanoma cells. In a co-culture Transwell system of keratinocytes and melanoma cells, galvanic zinc–copper microparticles reduced melanin production via downregulation of endothelin-1 secretion from keratinocytes and reduced tyrosinase gene expression in melanoma cells. In addition, exposure of pigmented epidermal equivalents to galvanic zinc–copper microparticles resulted in reduced melanin deposition. In conclusion, our data demonstrated for the first time that galvanic zinc–copper microparticles reduced melanogenesis in melanoma cells and melanin deposition in pigmented epidermal equivalents by affecting multiple pigmentary pathways.

Nutrient-Rich Botanicals in Skin Health: Focus on Avena sativa

Botanicals are generally defined as ingredients sourced from a natural feedstock such as a plant, fungus, microorganism or algae. Over time, certain botanicals have been selected for their nutritive or medicinal values. Interestingly some botanicals used as food source exhibit health benefits. Examples of nutrient-rich botanicals include oatmeal, vegetable oils, curcuma, pepper…etc. Until recently however, the mechanism of action of these botanicals was largely unknown. They were also mostly used as crude preparations. In addition, clinical evidence often lacked or was insufficient to support their rational usage. With the advances in preparation and extraction processes, standardized materials are now available. Moreover, research has been conducted in elucidating the chemical composition of such botanicals and determining the contribution of each phytochemical class to its mechanism of action.