Screening methods

An object is to establish a new screening method for the purpose of approaching the tissue forming the lip to search for a component that achieves the firm and puffy thick lip. A method for screening an agent for improving skeletal muscle cell activating action by lip-derived fibroblast, comprising the steps of: Culturing lip-derived fibroblast cells by adding a test substance; culturing the fibroblast culture supernatant by adding to skeletal muscle cells; and measuring the amount of myosin heavy chain protein 2 (MYH2) and/or myosin heavy chain protein 7 (MYH7) in the skeletal muscle cells, Wherein the expression level in skeletal muscle cells to which the test substance has been added is greater than the expression level in skeletal muscle cells to which the lip-derived fibroblast culture supernatant to which the test substance has not been added. Figure 5