Therapeutic potential of umbilical cord-derived mesenchymal stem cells in ameliorating ovarian aging: Insights from single-cell analysis

Figure 1 Umbilical cord-derived mesenchymal stem cell transplantation restores estrous cycle regularity in aged mice. A: Representative cytological images of the four estrous cycle stages. Diestrus is characterized predominantly by the presence of leukocytes. Proestrus shows mainly nucleated epithelial cells, with a small number of cornified epithelial cells and few leukocytes. Estrus is dominated by large numbers of anucleated cornified epithelial cells. Metestrus exhibits small, densely stained leukocytes mixed with a small proportion of cornified cells. Scale bar = 33.647 μm; B: Proportional distribution of each estrous cycle stage among the different groups. Note the significant prolongation of diestrus in the aged control group and its reversal in the umbilical cord-derived mesenchymal stem cell (UCMSC) transplantation group; C: Estrous cycles recorded over the 21-day observation period. UCMSC transplantation increased the total number of normal cycles in aged mice. ^bP < 0.01, ^dP < 0.0001. Y-CON: Young control; A-CON: Aged control; A-MSC: Umbilical cord-derived mesenchymal stem cell transplantation.