Immune effects of surgical menopause and estrogen replacement therapy in peri-menopausal women

Abstract

The complex relationship between sex hormones and immune function suggests that sex hormone deficiency and estrogen replacement therapy (ERT) in post-menopausal women may have pleiotropic effects on immune function. For this reason, we aimed to investigate short-term effects of surgical menopause and ERT on immunity profile in peri-menopausal women. Seventeen healthy peri-menopausal women who were to undergo total abdominal hysterectomy and bilateral salpingo-oopherectomy (TAH + BSO) for uterine myoma were enrolled into this study. Three blood samples were collected from each patient: 1-day prior to surgery, 30 days after the operation (before ERT) and 30 days after transdermal ERT. The percentages of peripheral blood lymphocyte subpopulations, serum interleukin-4 (IL-4) and interferon-gamma (IFN-γ) concentrations were determined by flow-cytometry and ELISA, respectively. Following TAH + BSO, the percentage of CD8 + cells was increased ( P<0.001) while the percentage of CD19 + cells, serum IL-4, and IFN-γ concentration and the ratio of CD4 + to CD8 + cells were decreased ( P<0.001, P<0.001, P<0.002, and P<0.05, respectively ). After ERT, this trend reversed and a decrease in the CD8 + cells ( P<0.001), increase in the CD19 + cells percentages ( P<0.02) and increase in serum IFN-γ concentration ( P<0.002) were observed. Although an increasing trend in the CD4 + to CD8 + ratio occurred by ERT, this was not significant. However, the decrease in the serum IL-4 concentration after TAH + BSO was not reversed by ERT. Hormone deficiency in post-menopausal women may cause an impaired immune response, and ERT can restore this phenomenon. Estrogen seems to have an important role in the regulation of immune function.