The Endocrine Role of Estrogens on Human Male Skeleton

Figure 3

Schematic representation of the role of estrogen and androgen bone size according to gender. The effects of sex steroids on cortical and trabecular bone are represented. Bone size is reached in late puberty and early adulthood as depicted at the left of the panel where the effect of each sex steroid and their sum are shown according to gender. In men, the combined action of both T and E₂ led to greater bone size and cortical thickness than in women. The prevailing effect of E₂ is consistent with higher endosteal bone formation in women. Bone loss during aging occurs in a different fashion between man and women and is subordinate to the baseline conditions. Women lose more bone on the endosteal surface and in the trabecular portion of bone, while men lose mainly bone mass in the cortical bone (right side of the panel). E₂: estradiol, T: testosterone; modified in part from figures published in [75, 77].