Preparing (P1) an aged skin equivalent, comprises: providing dermal matrices; providing a suspension of cells in a medium containing fibroblast, where the concentration of fibroblast is 50000-1500000 fibroblasts/ml of medium; equilibrating the matrices with cell-free fibroblast media; applying the suspension to the equilibrated matrices; culturing the fibroblasts onto the matrix; and treating cultured dermal matrices with mitomycin-C. Independent claims are also included for: (1) preparing of full-thickness skin equivalent, comprising: providing the aged dermis equivalent; seeding keratinocytes and/or melanocytes in the dermis; and culturing the keratinocytes and/or melanocytes on the dermis equivalent until complete formation of the full-thickness skin equivalent; (2) the aged skin equivalent obtained by the method; and (3) assessing efficacy of skin cosmetics, comprising: (a) providing the aged skin equivalent; (b) measuring the skin equivalent for at least one parameter including presence, quantity, expression and/or activity of procollagens, collagens, elastin, fibronectin, hyaluronic acid, glucosaminoglucanes, matrix metalloproteinases, and markers of differentiation of the epidermis (e.g. involucrin, filaggrin, transglutaminase or loricrin); (c) treating aged skin equivalent with a tropical applied skin cosmetic; (d) measuring the treated skin equivalent for at least one parameter including presence, quantity, expression and/or activity of procollagens, collagens, elastin, fibronectin, hyaluronic acid, glucosaminoglucanes, matrix metalloproteinases, and markers of differentiation of the epidermis (e.g. involucrin, filaggrin, transglutaminase or loricrin); (e) comparing the values of step (b) with the values of step (d); and evaluating the effectiveness of the skin cosmetics based on the influence of the presence, quantity, expression and/or activity of procollagens, collagens, elastin, fibronectin, hyaluronic acid, glucosaminoglucanes, matrix metalloproteinases, and markers of differentiation of the epidermis (e.g. involucrin, filaggrin, transglutaminase or loricrin).
