Klotho gene-deficient mice developed symptoms similar to those which occurred during human aging, such as atherosclerosis, ectopic calcification, emphysema, decreased motility, gonadal dysplasia, skin atrophy, hypoglycemia and severe hyperphosphatemia, whereas in mice overexpressing the Klotho gene, the symptoms of aging can be delayed [13]. Here, KL is linked to pulmonary emphysema.