Sensitive skin is a clinical syndrome characterized by the occurrence of unpleasant sensations, such as pruritus, burning or pain, in response to various factors, including skincare products, water, cold, heat, or other physical and/or chemical factors. Although these symptoms suggest inflammation and the activation of peripheral innervation, the pathophysiogeny of sensitive skin remains unknown. We systematically analysed cutaneous biopsies from 50 healthy women with non-sensitive or sensitive skin and demonstrated that the intraepidermal nerve fibre density, especially that of peptidergic C-fibres, was lower in the sensitive skin group. These fibres are involved in pain, itching and temperature perception, and their degeneration may promote allodynia and similar symptoms. These results suggest that the pathophysiology of skin sensitivity resembles that of neuropathic pruritus within the context of small fibre neuropathy, and that environmental factors may alter skin innervation.

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Purpose Age-related changes in skin structure and function can negatively impact skin quality. VYC-12L is a crosslinked hyaluronic acid filler for treating fine lines and improving hydration and elasticity. The goal of this study was to understand skin quality, histologic, and genomic changes underlying long-term clinical benefits of VYC-12L treatment. Patients and Methods In this prospective, nonrandomized, open-label study, 11 healthy men (n = 2) and women (n = 9) received intradermal VYC-12L treatment on the volar forearm. Clinical probes assessed skin quality at baseline and months 1 and 3 post-treatment. Punch biopsies were collected 1 and 3 months post-treatment to evaluate histologic and genomic changes. Safety was evaluated throughout. Results Participants had a mean age of 41 years and Fitzpatrick skin phototypes II (54.5%) and III (45.5%). At months 1 and 3, VYC-12L-treated skin had higher hydration in the stratum corneum than untreated skin. Cutometer measurements indicated treated skin that was firmer and more resistant to deformation. Histology showed increased epidermal AQP3 and Ki67 expression 1 and 3 months post-treatment and a qualitative increase in papillary dermal collagen I at month 3. Genomic analyses demonstrated treatment-related upregulation of genes involved in adipocyte differentiation, lipid metabolism, keratinocyte renewal, and dermal extracellular matrix (ECM) maintenance. Injection site reactions were mild-to-moderate in severity and resolved by month 1. Five participants reported 19 adverse events; most (68.4%) were related to the biopsy and none to VYC-12L. Conclusion VYC-12L produced changes in hydration, firmness, and ECM density and composition consistent with improved skin properties, demonstrating that VYC-12L can act as a substrate for tissue repair.

Oligomeric proanthocyanidins extracted from the bark of the French maritime pine Pinus pinaster (FMPBE) have been studied for a long time and demonstrated various phytopharmaceutical applications. The objectives of this study were to assess the cutaneous lightening and anti-ageing effects of FMPBE after 56 days of consumption, in healthy Asian women. The cosmetic efficacy of the product was assessed through various biometrological evaluations. This randomized, double-blind, placebocontrolled and cross-over study evidenced the safety and efficacy of the 100 mg FMPBE supplementation from 28 days of intake: in comparison to placebo, the skin on pigmentary spots became significantly lighter and less red, skin on the face was more firm and its surface was less wrinkled. After 56 days of consumption, the skin was additionally significantly more elastic and the yellow constituent of the skin decreased on the normal skin.Taken together, these results proved that FMPBE supplementation can be considered as an innovative approach to skin whitening and anti-ageing treatments. It represents an interesting alternative to topical products and supports the skin from the inside out.