title: No negative impact of reduced leptin secretion on bone metabolism in male decathletes.
abstract: This study investigated the effect of intense physical activities that generate high mechanical constraints on bone metabolism and serum leptin concentrations and the potential relationships among bone mineral density (BMD), bone biochemical markers and leptin variation. Thirteen male decathletes (mean age 22.4 +/- 2.9 years), nationally or internationally ranked (15.5 h/week of training), were compared with 13 healthy sedentary subjects (mean age 25.9 +/- 3.3 years). BMD was measured by DEXA and bone turnover was evaluated by specific markers. Leptin and calciotropic hormones levels were analysed in parallel. BMDs were higher in athletes than in controls at total body (13.9%), lumbar spine (17%), femoral neck (25%) and radius (9%), but not at the head. Athletes presented higher concentrations of osteocalcin (59.8%), cross-linked C-telopeptide of type-I collagen (41.1%) and 1,25-dihydroxyvitamin-D (37.1%). Basal leptin concentration was lower in athletes (0.94 +/- 0.54 vs. 5.07 +/- 1.1 ng ml(-1)), and this difference persisted when leptin levels were adjusted for whole body fat mass (WBFM). No difference was observed for bone-specific alkaline phosphatase or intact parathyroid hormone. Serum leptin levels were negatively correlated with various BMD values only when both the groups were pooled (n = 26). This relationship did not persist when leptin levels were adjusted for WBFM. Male athletes, who practise sports generating high mechanical constraints on the body, present a specific bone metabolism that includes high BMD, as well as high bone turnover. The blunted leptin secretion did not seem to have deleterious effect on the process of bone adaptation to high mechanical constraints.
authors.affiliation: Groupe de Recherche Interdisciplinaire Sur le Métabolisme Osseux, Montpellier, France. laurent.maimoun@laposte.net
authors.forename: Laurent
authors.initials: L
authors.lastname: Maïmoun
authors.forename: Olivier
authors.initials: O
authors.lastname: Coste
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Puech
authors.forename: Edouard
authors.initials: E
authors.lastname: Peruchon
authors.forename: Audrey
authors.initials: A
authors.lastname: Jaussent
authors.forename: Françoise
authors.initials: F
authors.lastname: Paris
authors.forename: Michel
authors.initials: M
authors.lastname: Rossi
authors.forename: Charles
authors.initials: C
authors.lastname: Sultan
authors.forename: Denis
authors.initials: D
authors.lastname: Mariano-Goulart
mesh_terms: D000328:Adult; D000469:Alkaline Phosphatase / Q000032:analysis / Q000378:metabolism; D015415:Biomarkers; D001823:Body Composition; D015519:Bone Density / Q000502:physiology; D016723:Bone Remodeling / Q000502:physiology; D001842:Bone and Bones / Q000378:metabolism*; D024042:Collagen Type I / Q000032:analysis / Q000378:metabolism; D004100:Dihydroxycholecalciferols / Q000032:analysis / Q000378:metabolism; D015444:Exercise / Q000502:physiology; D005269:Femur / Q000378:metabolism; D006801:Humans; D020738:Leptin / Q000172:deficiency*; D008159:Lumbar Vertebrae / Q000378:metabolism; D008297:Male; D015675:Osteocalcin / Q000032:analysis / Q000378:metabolism; D010281:Parathyroid Hormone / Q000097:blood / Q000378:metabolism; D013177:Sports
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D004100:Dihydroxycholecalciferols; D020738:Leptin; D010281:Parathyroid Hormone; D015675:Osteocalcin; D000469:Alkaline Phosphatase