title: Trunk fat negatively influences skeletal and testicular functions in obese men: clinical implications for the aging male.
abstract: Osteocalcin (OSCA) seems to act as a negative regulator of energy metabolism and insulin sensitivity. Evidence from male rodents suggests that OSCA may also regulate testosterone (T) synthesis. Using a cross-sectional design, we evaluated OSCA, 25(OH) vitamin D, T, 17 β -estradiol (E2), homeostasis model assessment of insulin resistance (HOMA-IR), and body composition in 86 obese (mean BMI = 34) male subjects (18-69 yr old). Independently from BMI, an inverse relationship between trunk fat percentage and plasma T (r (2) = -0.26, P < 0.01) and between HOMA-IR and OSCA levels (r (2) = -0.22, P < 0.005) was found. OSCA levels, as well as vitamin D, decreased significantly for higher BMI with significant differences above 35 (P < 0.01). A direct correlation between T and bone mineral density at lumbar (BMDL) and neck (BMDH) (P < 0.001, r (2) = -0.20; P < 0.001, r (2) = -0.24) was found, independently from age. An inverse correlation between E2 levels, BMDL, and BMDH (P < 0.001, r (2) = -0.20; P < 0.001, r (2) = -0.19) was observed. These data provide new evidences that a relationship between trunk fat mass, insulin sensitivity, OSCA and T synthesis occurs. This new relationship with skeletal health has relevant implications for the aging male, suggesting OSCA as a novel marker of metabolic and gonadal health status.
authors.affiliation: Department of Movement, Human and Health Sciences, Unit of Endocrinology, University of Rome "Foro Italico", Largo Lauro De Bosis 15, 00195 Rome, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Migliaccio
authors.affiliation: Department of Experimental Medicine, Medical Pathophysiology, Food and Science and Endocrinology Section, "Sapienza" University of Rome, Viale Regina Elena 324, 00161 Rome, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Francomano
authors.affiliation: Department of Experimental Medicine, Medical Pathophysiology, Food and Science and Endocrinology Section, "Sapienza" University of Rome, Viale Regina Elena 324, 00161 Rome, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Bruzziches
authors.affiliation: Department of Experimental Medicine, Medical Pathophysiology, Food and Science and Endocrinology Section, "Sapienza" University of Rome, Viale Regina Elena 324, 00161 Rome, Italy.
authors.forename: Emanuela A
authors.initials: EA
authors.lastname: Greco
authors.affiliation: Department of Experimental Medicine, Medical Pathophysiology, Food and Science and Endocrinology Section, "Sapienza" University of Rome, Viale Regina Elena 324, 00161 Rome, Italy.
authors.forename: Rachele
authors.initials: R
authors.lastname: Fornari
authors.affiliation: Department of Experimental Medicine, Medical Pathophysiology, Food and Science and Endocrinology Section, "Sapienza" University of Rome, Viale Regina Elena 324, 00161 Rome, Italy.
authors.forename: Lorenzo M
authors.initials: LM
authors.lastname: Donini
authors.affiliation: Department of Experimental Medicine, Medical Pathophysiology, Food and Science and Endocrinology Section, "Sapienza" University of Rome, Viale Regina Elena 324, 00161 Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lenzi
authors.affiliation: Department of Experimental Medicine, Medical Pathophysiology, Food and Science and Endocrinology Section, "Sapienza" University of Rome, Viale Regina Elena 324, 00161 Rome, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Aversa