Relationship between bone mineral density, leptin and insulin concentration in Brazilian obese adolescents

Author(s):Show less -

do Prado, Wagner Luiz ^[1] ; de Piano, Aline ^[2] ; Lazaretti-Castro, Marise ^[2] ; de Mello, Marco Tullio ^[3] ; Stella, Sergio Garcia ^[4] ; Tufik, Sergio ^[3] ; Oller do Nascimento, Claudia Maria ^[2] ; Oyama, Lila Missae ^[2] ; Lofrano, Mara Cristina ^[2] ; Tock, Lian ^[2] ; Caranti, Danielle Arisa ^[2] ; Damaso, Ana Raimunda ^[5]

Affiliation

^[1] Univ Pernambuco, Phys Educ High Sch, Recife, PE - Brazil

^[2] Univ Fed Sao Paulo, Nutr Postgrad Program, Paulista Med Sch, BR-04020060 Sao Paulo - Brazil

^[3] Univ Fed Sao Paulo, Dept Psychobiol, Paulista Med Sch, BR-04020060 Sao Paulo - Brazil

^[4] Univ Ribeirao Preto UNAERP, Sao Paulo - Brazil

^[5] Univ Fed Sao Paulo, Dept Biosci, Paulista Med Sch, BR-04020060 Sao Paulo - Brazil

• Document type: Journal article
• Source: JOURNAL OF BONE AND MINERAL METABOLISM; v. 27, n. 5, p. 613-619, SEP 2009.
• Web of Science Citations: 31

Abstract

Despite the epidemic of adolescent obesity, the effect of obesity and hormones on bone mineral accrual during growth is poorly understood. Studies using dual-energy X-ray to examine the effect of obesity on bone mass in children and adolescents have yielded conflicting results. The aim of this study was to explore the combined and independent contributions of body mass index, body composition, leptin, insulin, glucose levels and Homeostasis Model Assessment Insulin Resistance (HOMA-IR) to bone mineral density (BMD) and bone mineral content in a group of Brazilian obese adolescents. This study included 109 post-pubescent obese adolescents. A whole-body dual-energy X-ray absorptiometry scan was performed,using a HOLOGIC QDR4200, to determine whole-body BMD and body composition. Blood samples were collected in the outpatient clinic after an overnight fast, and evaluated for fasting blood glucose and immunoreactive insulin. Leptin levels were assessed with a radioimmunoassay kit. Insulin resistance was assessed by HOMA-IR and the quantitative insulin sensitivity check index. Our results showed that insulin levels and HOMA-IR correlated negatively with BMD and a linear regression analysis showed that serum leptin is inversely associated to BMD adjusted for body mass. In conclusion, our data support the hypothesis that leptin, insulin and HOMA-IR are inversely associated with BMD and play a significant direct role in bone metabolism. (AU)

• FAPESP's process: 06/00684-3 - Orexigenic, anorexigenic, pro and pre-inflamatory factors: effects of a multidisciplinary program for weight reduction in obese adolescents
• Grantee: Ana Raimunda Dâmaso
• Support Opportunities: Regular Research Grants