In many cultures, a youthful look is strictly linked to strong and healthy hair. Source of the hair fibre is the hair follicle, a highly specialized skin appendage. Biological alterations because of intrinsic or extrinsic stimuli can destabilize this perfectly organized system, thus effecting hair growth or metabolism. Also, ageing could be characterized as a disturbance in this wellbalanced machinery. Albeit the predominant symptom of hair ageing, greying, is addressed in a plurality of research activities, further age-related changes, e.g. related to hair structure, remain obscure. Therefore, we characterized hair follicles of two volunteer panels (below 25 years, above 50 years) on the molecular level, especially focussing on alterations influencing gene expression of keratins and keratin-associated proteins. We showed that concordantly to other biological systems the hair follicle undergoes several modifications during the ageing process associated among others with a significant decline in these structural proteins. Providing strategies to fight against these agerelated changes is a challenge for hair science.

IFSCC Magazine, 11 (2008) (1) 21-29 Proteoglycans take an important part in tissue homeostasis. In the skin, Proteoglycans are present in the extracellular matrix of dermis, particularly with lumican which plays an important role in dermal homeostasis. In the epidermis, several small proteoglycans such as the syndecans are synthesized and play an important role in keratinocyte activation. There is much data on the alteration during skin aging of the synthesis and structure of glycosaminoglycans and some proteoglycans but little information on small proteoglycans, in particular lumican and syndecan-1.We recently observed a decrease in the synthesis of these two small proteoglycans with aging. We confirm in this work the decrease in lumican in dermis and syndecan-1 in epidermis with aging. These proteoglycans represent original important targets for cosmetology in the fight against skin aging. In different in vitro models, two synthetic acetyl tetrapeptides, AcTP1 and AcTP2, stimulate the synthesis of lumican and syndecan-1, respectively. The beneficial action of AcTP1 on skin thickness and firmness and of AcTP2 on epidermal cohesion has been confirmed in vivo. IFSCC Magazine, 11 (2008) (1) 31-34 A water-in-powder cosmetic is one in which a large amount of water is encapsulated in a powder. In this study we describe the development of this type of cosmetic. We first focused on the hydrophilic/hydrophobic balance of the nano-sized powder surface. We looked at surface state of powders in the gas adsorption test and discovered functional powders that have an optimized balance of hydrorepellency and hydrophilicity due to fractal surface and free hydroxyl groups, respectively. Using this material we created a new powder technology that can encapsulate a large quantity of water in a stable structure. We also looked at how the powders encapsulated water by observing them with wet-SEM and how the encapsulated water is stabilized by measuring the water mobility with 17O-NMR. Based on these result, we developed a new technology with water and powder. By encapsulating a large amount of water, we achieved a cosmetic with many unique characteristics: The powder cosmetic can become a liquid by application of friction on skin, it is convenient to use and provides moist, cool feel. It also functions as an excellent makeup by spreading smoothly on skin to form a uniform makeup coating.