title: The effect of sexual hormone abnormalities on proximal femur bone mineral density in hemodialysis patients and the possible role of RANKL.
abstract: Sexual hormone concentrations are commonly affected in chronic renal failure. The contribution of sex steroids to bone turnover regulation implies that sex steroid's dysfunction may be implicated in the emergence of renal osteodystrophy. This study was conducted to evaluate sex steroids and gonadotrophins in hemodialysis (HD) patients and to investigate their role in bone homeostasis in concert with other hormones and cytokines. Bone mineral density (BMD) at the proximal femur and intact parathyroid hormone (iPTH), osteoprotegerin, soluble receptor activator of NF-kappaB ligand (sRANKL), prolactin, total testosterone, estradiol, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were measured in serum samples in 42 patients, 21 men and 21 women, on maintenance HD therapy. Possible associations between clinical characteristics, biochemical parameters, and BMD values were investigated. In male HD patients, the testosterone concentration declined significantly with aging, whereas the estradiol level increased with longer duration of HD. Concurrently, testosterone correlated negatively with sRANKL concentrations (r=-0.520, p=0.016). Luteinizing hormone levels in male patients demonstrated statistically significant negative correlations with BMD values of the proximal femur. In the entire cohort of patients, FSH and LH were negatively associated with absolute values of proximal femur BMD. Gonadotrophin and sexual hormone concentrations in HD patients are associated with bone mineral status and consequently their derangements appear to contribute to the development of bone composition abnormalities in different types of renal osteodystrophy. Furthermore, testosterone's association with sRANKL levels in male HD patients suggests that RANKL may mediate the effect of testosterone on bone metabolism in these patients.
authors.affiliation: Laboratory for Experimental Surgery and Surgical Research, Athens University, Athens, Greece. konsdoum@yahoo.gr
authors.forename: Konstantinos K
authors.initials: KK
authors.lastname: Doumouchtsis
authors.forename: Alkis I
authors.initials: AI
authors.lastname: Kostakis
authors.forename: Stergios K
authors.initials: SK
authors.lastname: Doumouchtsis
authors.forename: Eirini I
authors.initials: EI
authors.lastname: Grapsa
authors.forename: Ioanna A
authors.initials: IA
authors.lastname: Passalidou
authors.forename: Marios P
authors.initials: MP
authors.lastname: Tziamalis
authors.forename: Maria V
authors.initials: MV
authors.lastname: Poulakou
authors.forename: Ioannis S
authors.initials: IS
authors.lastname: Vlachos
authors.forename: Despoina N
authors.initials: DN
authors.lastname: Perrea
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D005260:Female; D005269:Femur; D005640:Follicle Stimulating Hormone / Q000097:blood; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000209:etiology / Q000628:therapy; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D008875:Middle Aged; D053245:RANK Ligand / Q000097:blood*; D012016:Reference Values; D006435:Renal Dialysis; D013739:Testosterone / Q000097:blood
chemical_list: D012739:Gonadal Steroid Hormones; D053245:RANK Ligand; C505688:TNFSF11 protein, human; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone