Childhood Obesity and Sexual Maturation

描述(由申请人提供)：本次修订的资助申请是R01HD38356美国儿童性成熟项目的竞争性延续，该项目是一项关于性成熟与体重、身高和BMI的横断面研究。竞争更新计划建议分析在FELS纵向研究中收集的287名男孩和269名女孩从出生到20岁的长期系列数据。女孩的乳房发育(性腺)通常先于阴毛(性腺)的出现，而男孩的生殖器发育(性腺)通常先于肾上腺的出现。在每种性别中，都有另一种途径，即女孩的肾上腺早于性腺原型，男孩的性腺原型先于性腺原型。具体目的是纵向检查(I)出生体重和身体成分对两种青春期途径的影响，以及(Ii)男孩和女孩的成熟率对同期和随后的身体脂肪、脂肪分布、瘦体重、血压、骨量、血脂和胰岛素抵抗的影响。鉴于这些参数与心血管疾病、2型糖尿病和晚年骨质疏松症的关系，这些参数非常重要。这一应用基于这样的观点，即身体组成与青春期和青春期的事件有关，通过促性腺激素轴、促生长激素轴、肾上腺雄激素、瘦素和胰岛素之间的紧密相互作用。在FELS数据集中对这些因素进行纵向建模将产生对青春期过程的机械性见解，还将有助于预测那些在以后的生活中代谢综合征组成部分风险最高的儿童。在FELS纵向研究中，我们收集了成熟度和身体成分指标的长期系列数据，以及瘦素、胰岛素、IGF-1、DHEAS和性腺类固醇以及心血管疾病、2型糖尿病和骨质疏松症的风险因素。这些数据为研究男孩和女孩的身体成分和性成熟之间的关系提供了一个独特的机会。FELS参与者在出生时就加入了这项研究，并没有根据与任何特定身体成分或临床状况相关的因素进行选择。建议的研究揭示的关系和得出的推论应反映出生体重和身体成分对性成熟的自然历史、脂肪和脂肪分布的发展、瘦体重、骨矿含量和日后疾病的相关风险因素的影响。

DESCRIPTION (provided by applicant): This revised grant application is a competing continuation of the project R01HD38356 Sexual Maturity in US Children which is a cross-sectional study of sexual maturation and body weight, height, and BMI. The competing renewal proposes to analyze long-term serial data collected from birth to 20 years of age in 287 boys and 269 girls in the Fels Longitudinal Study. In girls breast development (thelarche) usually precedes the appearance of pubic hair (adrenarche), and in boys genital development (gonadarche) usually precedes adrenarche. In each sex there is an alternate pathway in which adrenarche precedes thelarche in girls or gonadarche in boys. The specific aims are to examine, longitudinally, (i) the impact of birth weight and body composition on the two pubertal pathways and (ii) the effects of rate of maturation in boys and girls on contemporaneous and subsequent body fat, fat distribution, lean body mass, blood pressure, bone mass, lipid profiles, and insulin resistance. These parameters are important in view of their relationship to cardiovascular disease, type 2 diabetes, and osteoporosis later in life. This application rests on the idea that body composition is related to the events of puberty and adolescent growth by closely intertwined interactions between the gonadotropic axis, the somatotropic axis, adrenal androgens, leptin, and insulin. Longitudinal modeling of these factors in the Fels data set will yield mechanistic insights into the pubertal process and will also aid in predicting those children who are most at risk for components of the metabolic syndrome later in life. In the Fels Longitudinal Study we have collected long-term serial data for indicators of maturation and body composition, and leptin, insulin, IGF-1, DHEAS, and gonadal steroids as well as risk factors for cardiovascular disease, type 2 diabetes, and osteoporosis. These data provide a unique opportunity to study the relationships between body composition and sexual maturation in boys and girls. The Fels participants are enrolled into the study at birth and are not selected in regard to factors associated with any particular body composition or clinical condition. The relationships revealed and the inferences drawn from the proposed study should reflect the impact of birth weight and body composition on the natural history of sexual maturation and the development of fat and fat distribution, lean body mass, bone mineral content and related risk factors for disease later in life.