Oligomeric α-Synuclein induces skin degeneration in reconstructed human epidermis.

Aged and photoaged skin exhibit fine wrinkles that are signs of epidermal inflammation and degeneration. It has been shown that healthy elderly skin expresses amyloidogenic proteins, including α-Synuclein, which are known to oligomerize and trigger inflammation and neurodegeneration. However, little is known about their putative role in skin physiology and sensitivity.

Real-Time Fluorescence Microscopy on Living Sheds New Light on the Antibacterial Effects of the King Penguin β-Defensin AvBD103b.

(1) Antimicrobial peptides (AMPs) are a promising alternative to conventional antibiotics. Among AMPs, the disulfide-rich β-defensin AvBD103b, whose antibacterial activities are not inhibited by salts contrary to most other β-defensins, is particularly appealing. Information about the mechanisms of action is mandatory for the development and approval of new drugs.

Characterization of a New Reconstructed Full Thickness Skin Model, T-Skin™, and its Application for Investigations of Anti-Aging Compounds.

Background: We have characterized a new reconstructed full-thickness skin model, T-Skin™, compared to normal human skin (NHS) and evaluated its use in testing anti-aging compounds.

Methods: The structure and layer-specific markers were compared with NHS using histological and immunohistological staining. In anti-aging experiments, T-Skin was exposed to retinol (10 µM) or vitamin C (200 µM) for 5 days, followed by immunohistological staining evaluation.

Effect of Fluorination on Skin Sensitization Potential and Fragrant Properties of Cinnamyl Compounds.

A series of three α- and three β-fluorinated representatives of the family of cinnamate-derived odorants (cinnamaldehyde (1), cinnamyl alcohol (2), and ethyl cinnamate (3)) as used as fragrance ingredients is described. Olfactive evaluation shows that the fluorinated compounds exhibit a similar odor profile to their parent compounds, but the olfactive detection thresholds are clearly higher. In vitro evaluation of the skin sensitizing properties with three different assays indicates that α-fluorination of Michael acceptor systems 1 and 3 slightly improves the skin sensitization profile.

Native Chemical Ligation Strategy to Overcome Side Reactions during Fmoc-Based Synthesis of C-Terminal Cysteine-Containing Peptides.

The Fmoc-based solid phase synthesis of C-terminal cysteine-containing peptides is problematic, due to side reactions provoked by the pronounced acidity of the Cα proton of cysteine esters. We herein describe a general strategy consisting of the postsynthetic introduction of the C-terminal Cys through a key chemoselective native chemical ligation reaction with N-Hnb-Cys peptide crypto-thioesters. This method was successfully applied to the demanding peptide sequences of two natural products of biological interest, giving remarkably high overall yields compared to that of a state of the art strategy.