Cultured muscle cells with high metabolic activity and method for production of the cultured muscle cells

摘要

The object of the present invention is to provide a method of preparing excellent cultured muscle cells having high metabolic capacity and insulin responsiveness, and further provide a method for the measurement of sensitive metabolic capacity using the cells. Moreover, its purpose is to provide a culture system/culture apparatus that can smoothly translocate such highly advanced cultured muscle cells intact to activity evaluation systems of a number of drugs. Moreover, the object of the present invention is to provide cultured muscle cells that are very suitable for measurement of the membrane-translocation activity of GLUT4 in an extraneous stimulus-dependent manner such as insulin, etc., and to provide a method for the measurement of the membrane-translocation activity of GLUT4 using the cells. The present invention is a method of preparing myotube cells, comprising a step (1) of culturing myoblast cells, a step (2) of differentiation-inducing the myotube cells into the myoblast cells in a culture medium with a high content of amino acids, and a step (3) of applying an electric pulse to the differentiation-induced myotube cells, and a method for the measurement of insulin-dependent sugar uptake using the myotube cells prepared by said method, and relates to the method for the measurement, comprising applying insulin stimulation by culturing the cells in a culture medium containing insulin, culturing the cells in the culture medium further supplemented with sugar, and measuring the sugar uptake. Furthermore, the present invention relates to a differentiation-type culture myotube cell constitutively expressing a recombinant GLUT4 having a labeled substance at its extra-cellular site, which is prepared by co-culturing wild-type myoblast cells and recombinant myoblast cells constitutively expressing said recombinant GLUT4, and a method for the measurement of membrane-translocation activity of the recombinant GLUT4 using the cells, and particularly a method for the measurement of insulin-dependent sugar uptake activity.