Maturitas 88 (2016) 32–36 Contents lists available at ScienceDirect Maturitas jou rn al hom ep age: www.elsevier.com/locate/maturitas Serum leptin, adiponectin and ghrelin concentrations in post-menopausal women: Is there an association with bone mineral density? V. Mpalaris a , P. Anagnostis b , A.D. Anastasilakis c , D.G. Goulis b , A. Doumas a , I. Iakovou a,∗ a Department of Nuclear Medicine, Aristotle University, Papageorgiou Hospital, 56403 Thessaloniki, Greece b Unit of Reproductive Endocrinology, 1st Department of Obstetrics and Gynecology, Medical School, Aristotle University of Thessaloniki, Greece c Department of Endocrinology, 424 General Military Hospital, Thessaloniki, Greece a r t i c l e i n f o Article history: Received 31 October 2015 Received in revised form 29 January 2016 Accepted 3 March 2016 Keywords: Adipokine Adiponectin Ghrelin Leptin Osteoporosis a b s t r a c t Objective: Adipokines and ghrelin exert well-documented effects on energy expenditure and glucose metabolism. Experimental data also support a role in bone metabolism, although data from clinical studies are conflicting. The purpose of this cross-sectional study was to investigate the association of serum concentrations of leptin, adiponectin and ghrelin with bone mineral density (BMD) in post-menopausal women. Methods: BMD in lumbar spine and femoral neck, and circulating leptin, adiponectin and ghrelin con- centrations were measured in 110 healthy post-menopausal women. Patients with secondary causes of osteoporosis were excluded. Results: Osteoporosis was diagnosed in 30 (27%) women and osteopenia in 54 (49%). Serum leptin con- centrations were positively correlated with both lumbar spine (r = 0.343, p < 0.01) and femoral neck BMD (r = 0.370, p < 0.01). Adiponectin concentrations were negatively associated with BMD at both sites (r = −0.321, p < 0.01 and r = −0.448, p < 0.01 respectively). No significant correlation between ghrelin con- centrations and BMD was found. Osteoporotic women had lower body weight, body mass index (BMI) and leptin concentrations, but higher adiponectin concentrations compared with non-osteoporotic women. In multivariate stepwise regression analysis, the association of adiponectin concentrations with BMD remained significant only for femoral neck, after adjustment for body weight or BMI. Conclusions: An inverse association between adiponectin and femoral neck BMD was found in post- menopausal women, independently of body weight. The positive association between leptin and BMD was dependent on body weight, whereas no effect of ghrelin on BMD was evident. © 2016 Elsevier Ireland Ltd. All rights reserved. 1. Introduction Obesity and osteoporosis are important public health problems with increasing prevalence in the developed world. Obesity was initially considered protective for the skeleton, as a positive cor- relation between body weight and bone mineral density (BMD) at all skeletal sites was confirmed in many studies, in both sexes [1]. Abbreviations: BMD, bone mineral density; BMI, body mass index; CV, co-efficient of variation; DXA, Dual-energy X-ray Absorptiometry; ELISA, enzyme- linked immunosorbent assay; IRMA, immunoradiometric; IQR, interquartile range; RANK, receptor activator of nuclear factor k; RIA, radioimmunoassay; SHBG, sex hormone-binding globulin; WHR, waist-to-hip ratio. ∗ Corresponding author. E-mail addresses: iiakovou@auth.gr, iiakovou@icloud.com (I. Iakovou). However the association between body weight and fracture risk is more complex [2]. Several theories have been proposed in order to explain the correlation of body weight with BMD: increased mechanical loading of the skeleton in obese individuals, increased insulin concentrations due to insulin resistance, increased estrogen aromatization in adipose tissue, reduced levels of sex hormone- binding globulin (SHBG) and common origin of osteoblasts and adipocytes [1]. Due to the discovery of adipokines, adipose tissue is not consid- ered just a fat depot but a complex endocrine organ contributing to the regulation of many metabolic processes. The first to be dis- covered and best studied adipokine is leptin, followed shortly by adiponectin. Leptin acts at the hypothalamic level, as a satiety sig- nal, controlling appetite and energy expenditure, according to the levels of energy stored as body fat. It is elevated in obese patients and insulin resistance states. Hyperleptinemia is also associated http://dx.doi.org/10.1016/j.maturitas.2016.03.004 0378-5122/© 2016 Elsevier Ireland Ltd. All rights reserved.