FGFR1 and Marchiafava-Bignami disease: After the treatment of FPS or CTR for 3 weeks, the expression of Klotho, not FGFR1, in renal tubulointerstitium and in the kidneys of the CKD–MBD model rats was ameliorated, respectively, compared to that of the CKD–MBD group rats (Figures 5C,D).