Childhood Obesity and Sexual Maturation

描述（由申请人提供）：本修订后的资助申请是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。竞争更新建议分析费尔斯纵向研究中从出生到20岁收集的287名男孩和269名女孩的长期序列数据。在女孩中，乳房发育（乳腺发育）通常先于阴毛（肾上腺增生）出现，而在男孩中，生殖器发育（性腺增生）通常先于肾上腺增生。每一种性别都有一个交替的途径，女孩的肾上腺激素先于性腺激素，男孩的性腺激素先于性腺激素。具体目的是纵向检查：(i)出生体重和身体组成对两个青春期途径的影响；（ii）男孩和女孩的成熟速度对同期和随后的体脂、脂肪分布、瘦体重、血压、骨量、脂质谱和胰岛素抵抗的影响。鉴于这些参数与晚年心血管疾病、2型糖尿病和骨质疏松症的关系，这些参数很重要。这一应用基于这样一种观点，即身体成分通过促性腺轴、促生长轴、肾上腺雄激素、瘦素和胰岛素之间紧密交织的相互作用，与青春期和青少年生长事件相关。在费尔斯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制见解，也将有助于预测那些在以后的生活中最有可能患上代谢综合征的儿童。在Fels纵向研究中，我们收集了成熟和身体组成指标、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危险因素的长期序列数据。这些数据为研究男孩和女孩的身体组成和性成熟之间的关系提供了一个独特的机会。Fels参与者在出生时就被纳入研究，而不是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。所揭示的关系和从拟议的研究中得出的推论应反映出生体重和身体组成对性成熟的自然史和脂肪的发展以及脂肪分布、瘦体重、骨矿物质含量和晚年疾病的相关危险因素的影响。

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.