As expected, although both irisin and clinically used drug combinations improved bone quality to the same extent (Figure 7B), clinically used drug combinations significantly increased kidney burden in CKD mice, whereas irisin did not alter renal function markers (Figure 7C), suggesting that irisin administration is a kidney friendly, potent antirenal osteodystrophy monotherapy. The gene discussed is FNDC5; the disease is chronic kidney disease.