Profound Changes in Sex Hormone Levels during Cross-Sex Hormone Therapy of Transsexuals do not Alter Serum Cholesterol Acceptor Capacity

IntroductionMen and postmenopausal women exhibit a higher risk for atherosclerosis than premenopausal women. These differences were often attributed to sex steroids, but the role of estrogen and testosterone in atherosclerosis are more complex than anticipated. Cross-sex hormone therapy of transsexuals is an interesting model, which has been used to study hormonal effects on serum lipid profile, insulin resistance, and body composition. However, studies on macrophage cholesterol efflux, the first step in reverse cholesterol transport, are not available.AimThe aim of this study was to evaluate the effect of cross-sex hormone therapy in transsexuals on the capacity of serum to accept cholesterol from macrophages.MethodsCholesterol acceptor capacity (CAC) of serum from transsexuals before and after at least 6 months of hormone treatment was measured using macrophage tissue culture models.Main Outcome MeasuresCAC of serum using the human acute monocytic leukemia cell line (THP-1 cells).ResultsUnexpectedly, the CAC of serum from male to female (MtF) transsexuals was not increased, but decreased after hormone therapy. Serum from female to male (FtM) transsexuals showed no changes in CAC.ConclusionsDespite drastic changes in hormone status, no increase in CAC was detected in MtF patients, and no alteration in CAC was seen in FtM patients. These data further challenge the traditional view that estrogen and testosterone exert beneficial and detrimental effects, respectively, on lipoprotein metabolism and ultimately atherosclerosis. Wultsch A, Kaufmann U, Ott J, Stojakovic T, Scharnagl H, Stangl H, and Strobl WM. Profound changes in sex hormone levels during cross-sex hormone therapy of transsexuals do not alter serum cholesterol acceptor capacity. J Sex Med 2015;12:1436–1439.