Probiotic Microbes Sustain Youthful Serum Testosterone Levels and Testicular Size in Aging Mice
a. Representative histology of Swiss mouse testes at the age of 12 months. The aged control mouse testes demonstrated atrophic seminiferous tubules. By contrast, L. reuteri-fed mice had uniformly normal ST epithelium with rare atrophic tubules. Hematoxylin and eosin. Bars = 100 µm. The y-axis in the bar graph stands for the mean±SEM of the atrophic/total ST ratio counted in each experimental group;**p<0.001. b. Ki-67-specific immunohistochemistry in the testes of 12-months-old mice. A side-by-side comparison of representative images from control and L. reuteri-fed mouse testes reveals that the probiotic organism counteracts the age-associated decrease of epithelial proliferation observed in control mice. DAB chromogen, Hematoxylin counterstain. Bars = 100 µm.