Figure 4. L. reuteri increases Leydig cell proliferation and serum testosterone levels.
a. At the age of 5 months a small number of proliferating (Ki-67+) Leydig cells did exist in the testicular interstitium (arrows). Proliferating Leydig cells were significantly more in probiotic-fed mice. DAB chromogen, Hematoxylin counterstain. Bars = 25 µm. The y-axis of the bar graph stands for the mean±SEM of Ki-67+ Leydig cells. b. Serum testosterone levels are significantly higher when consuming L. reuteri, as compared to their diet-matched controls. Numbers on the y-axis corresponds to the mean±SEM of serum testosterone level in ng/ml.; *p<0.05, **p<0.001.