Method for evaluating mesenchymal stem cell activity, method for culturing mesenchymal stem cells, method for producing therapeutic agent for liver dysfunction, and therapeutic agent for liver dysfunction

The present invention relates to a method for evaluating the extent of mesenchymal stem cell activity, and a method for culturing mesenchymal stem cells using the evaluation method in the field of culturing mesenchymal stem cells for regenerative medicine, and further, a method for producing a therapeutic agent for liver dysfunction and a therapeutic agent for liver dysfunction. This method for evaluating mesenchymal stem cell activity comprises an assay step for assaying the amount of adenylate kinase 4 (AK4) in mesenchymal stem cells and an assessment step for assessing the extent of mesenchymal stem cell activity from the assayed amount of AK4. In this method the extent of mesenchymal stem cell activity can be evaluated from the assayed amount of AK4, for instance, if the extent of mitochondrial activity of mesenchymal stem cells is high the mesenchymal stem cells can be evaluated as ideal for use as a therapeutic drug, while if mitochondrial activity of the mesenchymal stem cells is low and aging does not proceed, the mesenchymal stem cells can be evaluated as suitable for subculture.