The invention relates to a use of a stem cell conditioned medium for manufacturing a composition to induce ZO-1 gene expression for skin firming. First, mesenchymal stem cells are cultured in a cell culture dish containing complete growth media, wherein the complete growth media including α-MEM, fetal bovine serum, and human-basic fibroblast growth factor therein. After mesenchymal stem cells are sub-cultured in the complete growth media for three times, a conditioned medium can be acquired from the basal medium. Accordingly, cosmetics containing the appropriate amount of conditioned medium can proceed with renewal and dense arrangement for skin cells so as to achieve efficacy of skin firming.本發明係有關於一種幹細胞條件培養基用於製備促進皮膚細胞ZO-1基因表現達到皮膚緊實之組成物的用途;其係先將間葉幹細胞生長於含有完全培養基(complete growth medium)的細胞培養皿中,其中完全培養基包含有α-MEM、胎牛血清(Fetal bovine serum)以及人類鹼性成纖維細胞生長因子(human-basic fibroblast growth factor),係於間葉幹細胞繼代培養三代後收集而得條件培養基;藉此,含有適量條件培養基的化妝品可讓細胞分子正確進行重建以及緊密排列,而達到皮膚緊緻的效果。
