Fig. 1

Oral administration of 20 mM D-Ser or D-Ala improves renal function in female 5/6-Nx mice. Plasma Ala, Ser, Asn, and Pro levels were measured in male and female mice (a–d); D-amino acid (ab) and L-amino acid levels (cd) were shown. Survival data of female (e–h) and male mice (i) orally administered D-Ser or D-Ala are shown. Female 5/6-Nx mice treated with D-Ser (e) and D-Ala (f) survived longer than untreated female 5/6-Nx mice (p < 0.05). No significant difference was found between the survival time of 5/6-Nx female mice treated with D-Ser (g) and D-Ala (h) and that of sham female mice. Statistical analysis was performed using the Kaplan–Meier method. Ala alanine, Ser serine, Asn asparagine, Pro proline, Nx nephrectomy.