J. Cosmet. Sci., 65, 389–401 (November/December 2014) 389 Trophic effect of a methanol yeast extract on 3T3 fi broblast cells DOMINIQUE GALLO, MONIQUE DILLEMANS, DAVID ALLARDIN, FABIAN PRIEM, LAURENCE VAN NEDERVELDE, Commission communautaire française (Cocof), Service des Industries Biochimiques, Institut Meurice, 1070 Brussels, Belgium (D.G., M.D., D.A., L.V.N.), Commission communautaire française (Cocof), Département des Substances Naturelles et de Biochimie, Institut Meurice, 1070 Brussels, Belgium (D.G.), Eleonor sprl, 1310 La Hulpe, Belgium (F.P.). Accepted for publication October 20, 2014. Synopsis With regard to the increase of human life expectancy, interest for topical treatments aimed to counteract skin aging is still growing. Hence, research for bioactive compounds able to stimulate skin fi broblast activity is an attractive topic. Having previously described the effects of a new methanol yeast extract on growth and metabolic activity of Saccharomyces cerevisiae, we studied its effects on 3T3 fi broblasts to evaluate its potential antiaging property. This investigation demonstrates that this extract increases proliferation as well as migra- tion of 3T3 cells and decreases their entrance in senescence and apoptosis phases. Altogether, these results open new perspectives for the formulation of innovative antiaging topical treatments. INTRODUCTION Skin is an organ the function of which is mainly to protect an organism against the external environment. In one way, skin impedes physical, chemical, and microbiologi- cal hazards and in the other, it regulates loss of water, electrolytes, and heat (1). More- over, known to contain a large number of Langerhans cells, skin is considered a real sentry with regard to body immunity (2). In addition, the extensive nerve network present in skin makes an effective sensory link between organism and its environment. Epidermis, dermis, and hypodermis are the three main layers of the skin. It should be stressed that these layers derive from different embryonic origins. While epidermis derives from ectoderm, dermis and hypodermis are both of mesodermal origin. Thus, by contrast to epidermis, which is mostly composed of epithelial cells, dermis and hy- podermis are mainly composed of mesenchymal cells (i.e., fi broblasts and adiposities, respectively). Address all correspondence to Monique Dillemans at mdillemans@hotmail.fr.

JOURNAL OF COSMETIC SCIENCE 390 Besides its biological and physiological functions, skin is a predominant factor in terms of physical appearance, like a “social interface,” it is an essential beauty criterion (3). Skin structure and appearance alterations caused, for instance, by aging or by sun exposure are often not well accepted. Hence, use of cosmetic treatments formulated to slow down skin damages is extremely widespread. Furthermore, progresses made in the fi eld of medicine increase life expectancy (4) we can easily assume that demand of this type of topical treat- ment will constantly increase (5). By contrast to most internal organs that mainly age through intrinsic mechanisms (chronological aging), aging of the skin is also subjected to extrinsic factors (environmen- tal stresses) (6). Together, these two types of alterations often result in well-known char- acteristics: skin undergoes pigmentation changes and becomes wrinkled, saggy, and dry. Actually, most physical damages have their origin in dermis thickness reduction induced by fi broblast number and activity decreases. Hence, preservation or restoration of dermal fi broblast function is a goal that many anti-aging cosmetics claim to reach. It is usually considered that free radicals are largely responsible for skin aging. Thus, most cosmetic treatments contain natural (i.e., retinol, ascorbic acid, tocopherol, etc.) or modifi ed (i.e., tetra-isopalmitoyl ascorbate, tocopherol acetate, etc.) antioxidant com- pounds (7,8). It is also generally known that extracts from yeast S. cerevisiae may also be benefi cial with regard to skin texture and appearance (8). To date, mainly two types of bioactive yeast extracts have emerged: chromium- and β-glucan-rich extracts (9–15). Meanwhile, another type of yeast extract (MYE for Methanol Yeast Extract), has been described in a different context which is that of the alcoholic fermentation. This extract differs from traditional yeast extracts by its mode of production. Our group and others have shown that it had a positive effect on S. cerevisiae (16–19). Actually, MYE has been shown to accelerate the metabolism of carbohydrates via an increase in glucose transport, glycolytic fl ux, and intracellular content of fructose-2,6-bisphosphate and via the activa- tion of the pyruvate decarboxylase. It was also shown that this extract was able to increase S. cerevisiae resistance to various stresses such as oxidative, alcoholic, osmotic, and UV- induced. In addition, MYE increases longevity of S. cerevisiae, a reference model for study- ing genetic and physiological modulations regulating longevity in higher organisms (20). Thus, all these observations led us to study the effect of this extract on higher eu- karyotic cells and particularly on fi broblasts that play a major role in dermis structure. MATERIAL AND METHODS YEAST EXTRACTION METHOD Two kilograms of pressed yeast S. cerevisiae (Algist Bruggeman, Gent, Belgium) were ex- tracted with 2 l of pure methanol at room temperature and stirred for 24 h. After cen- trifugation and fi ltration, the bioactive fraction contained in the supernatant was precipitated by addition of 4 volumes of acetone. The precipitate was then recovered in 500 ml of distilled water and the bioactive fraction was isolated by differential precipita- tion with ethanol. Briefl y, after addition of 35% v/v ethanol, precipitated fraction was discarded and after adding 50% ethanol, precipitated fraction was, this time, recovered (viscous precipitate). Consecutive additions of ethanol at 70% and 100% induced the precipitation of inactive compounds. Note that all fractions were tested with regard to