Figure 6

Bisphenol A (BPA) effect on stemness activity of spermatogonial stem cells after long-term BPA exposure and recovery from 100 µM BPA treatment. (A) Diagram of continuous BPA exposure method and subsequent transplantation into recipient mice. (B) Germ cell numbers following BPA exposure in culture for 3 consecutive weeks (n = 5). Significant differences (P < 0.05) analyzed by one-way ANOVA are indicated by different letters (a, b, and c). Long-term BPA-exposed germ cells transplanted into recipient mice. Ratios of the number of donor cell derived colonies (C) per 10⁵ transplanted germ cells and (D) total number of cultured germ cells are showed as bar graph. Total numbers of mice/testes analyzed were 8/14, 6/11 and 7/10 for control, 1, and 10 µM BPA concentrations, respectively. Different letters (a and b) indicate significant differences (P < 0.05) between treatments. (E) Diagram of the method of recovered germ cells from 1 week 100 µM BPA exposure and subsequent transplantation into recipient mice. (F) Germ cell numbers of control and recovered cells from 100 µM BPA exposure are cultured for 3 consecutive weeks without BPA (n = 5). Analysis of donor derived colonies of recovered germ cells (G) per 10⁵ transplanted germ cells and (H) total number of cultured germ cells. Total numbers of mice/testes analyzed were 9/16 and 6/12 for control and 100 µM BPA recovered, respectively. Values with superscript characters (*) indicate significant differences analyzed by t-test (*compared with control, P < 0.05; ***compared with control, P < 0.001).