Research Paper Volume 15, Issue 20 pp 10856—10874

Figure 3. Mitochondrial function in the ovaries of a NOD/SCID mouse model for physiological human aging. (A) Relative mitochondrial/nuclear DNA (mtDNA/nDNA) ratio in the ovarian tissue of young, advanced maternal age (AMA) and old mice, based on the RT-qPCR amplification of ND1 and COX3 mitochondrial genes normalized to the nuclear 18S gene shows a reduced number of mitochondrial copies in aged groups. Note, ND1 and COX3 were selected from the stable regions of the mouse mtDNA (depicted as the purple, blue, and green segments). (B) Photomicrograph of ovarian sections shows oxidative damage (brown) visualized with the immunohistochemical staining of the peroxidative lipid product 4-hydroxynonenal (4-HNE), and corresponding quantification of the damaged tissue is higher in older mice. The black scale bars are set to 100 μm. (C) Representative immunofluorescent images of cell death (indicated by TUNEL-positive red signal), and the corresponding quantification of apoptotic cells notice more apoptosis in older mice. White scale bars are set to 100 μm. All analyses were based on four samples per group. ^*p < 0.05 AMA and Old vs. young, ^#p < 0.05 Old vs. AMA.