Patients with CKD show a decreased level of PrPC, and CKD patient–derived MSCs show decreased mitochondrial functionality. (A, B) Patients with CKD (n = 25) and healthy control groups (Healthy control; n = 10): estimated glomerular filtration rate (eGFR), and PrPC in each group in their serum (100 μL samples). Values represent the mean ± SEM. **p < 0.01 vs. Healthy control. (Student's t-test was used). (C) A graph on eGFR-axis against the concentration on the PrPC-axis. (D) We measured PrPC concentrations of Healthy-hMSCs (n = 4) and CKD-hMSCs (n = 4) by ELISA. Values represent the mean ± SEM. *p < 0.05, and **p < 0.01 vs. untreated Healthy-hMSCs. (Student's t-test was used). (E) Immunoprecipitates with an anti-PINK1 antibody were analyzed for Healthy-hMSCs (n = 2) and CKD-hMSCs (n = 4) by western blotting using an antibody that recognized PrPC. (F) The level of PrPC, whose binding with PINK1 was normalized to that of VDAC1. Values represent the mean ± SEM. *p < 0.05, and **p < 0.01 vs. untreated Healthy-hMSCs. (Student's t-test was used). (G, H) Complex Ⅰ and complex Ⅳ activities were analyzed in Healthy-hMSCs and CKD-hMSCs by ELISAs. Values represent the mean ± SEM. *p < 0.05, and **p < 0.01 vs. untreated Healthy-hMSCs. (Student's t-test was used). (I) The positive signals of MitoSOX were quantified by FACS analysis with staining of Healthy-hMSCs and CKD-hMSCs. Values represent the mean ± SEM. *p < 0.05, and **p < 0.01 vs. untreated Healthy-hMSCs. (Student's t-test was used). (J) Representative TEM images (n = 3 per group) of Healthy-hMSCs and CKD-hMSCs. Scale bars are shown enlarged on the left. Scale bars: 500 nm. (K) Quantitative analyses of morphometric data from TEM images. Values represent the mean ± SEM. *p < 0.05, and **p < 0.01 vs. untreated Healthy-hMSCs. (Student's t-test was used). (L) Percentages of abnormal mitochondria that were swollen with evidence of severely disrupted cristae throughout a mitochondrion) obtained from a TEM image. Values represent the mean ± SEM. *p < 0.05, and **p < 0.01 vs. untreated Healthy-hMSCs. (Student's t-test was used).