FNDC5 and columnar cell hyperplasia of the breast: BCAS injure induced significant reduction of Fndc5 gene expression as well as irisin concentration in forebrain (Fndc5 mRNA: P = 0.001, irisin: P = 0.049; Fig. 1F), hippocampus (Fndc5 mRNA: P = 0.001, irisin: P = 0.009; Fig. 1G) and cerebellum (Fndc5 mRNA: P = 0.220, irisin: P = 0.361; Fig. 1H) of ageing mice, suggesting the activity of Fndc5/irisin is totally inhibited in brain with CCH.