Effect of hormone replacement therapy on the production of bone-resorbing cytokines by peripheral blood cells in postmenopausal women.

We studied the effects of hormone replacement therapy (HRT) with estrogen on postmenopausal changes in the production of bone-resorbing cytokines interleukin 1 beta (IL-1β) and tumor necrosis factor alpha (TNFα). Both cytokines were measured in the supernatants of lipopolysaccharide (LPS)-stimulated whole-blood cells from 72 untreated and 44 HRT-treated women by ELISA. The levels of IL-1β were significantly higher in women in their 40 s and 50 s and in postmenopausal women than in women in their teens, 20 s and 30 s, while the levels of TNFα did not show any changes related to age. Both levels in HRT-treated women were significantly lower than those in untreated women at almost every postmenopausal stage. In a prospective study, HRT induced significant declines in both levels. These results show that estrogen decreases the accelerated production of ILAP and reduces the production of TNFα in postmenopausal women at each postmenopausal stage, even in late-postmenopausal women.