Dis Markers. 2013;35(4):249-59. doi: 10.1155/2013/531736.
The hypothalamus is important in hunger and metabolism. Although a lot is known about the basic role of the human hypothalamus, less is known about how the in vivo volume is affected in obesity, particularly among adolescents. Based on pediatric body mass index percentiles, 95 participants were assigned to lean or obese groups. All subjects had medical evaluations, including fasting blood tests, to assess insulin sensitivity and circulating CRP and neurotrophins (NGF and BDNF) and an MRI of the brain. Hypothalamic volumes were measured by a segmentation method combining manual and automated steps. Overall, obese participants had descriptively smaller hypothalamic volumes, although this difference did not reach statistical significance; however, among obese participants, females had significantly smaller hypothalamic volumes than their male counterparts. There was a significant interaction between insulin resistance and sex on hypothalamus volume; obese females with significant insulin resistance have smaller hypothalamic volumes than obese males. Obese adolescents had higher circulating CRP and neurotrophin levels. Furthermore, among obese females, BDNF concentrations were inversely associated with hypothalamus volumes (r = −0.48). Given this negative association between BDNF and hypothalamus volumes among obese insulin-resistant females, elevated neurotrophin levels may suggest an attempt at protective compensation.
下丘脑在饥饿和新陈代谢中起着重要作用。尽管人们对人类下丘脑的基本作用了解很多，但对于肥胖症患者（尤其是青少年）体内体积如何受到影响的了解较少。根据儿科体重指数百分位数，将 95 名参与者分配到瘦组或胖组。所有受试者都接受了医学评估，包括空腹血液检查，以评估胰岛素敏感性和循环 CRP 以及神经营养因子（NGF 和 BDNF），并对大脑进行了 MRI 检查。通过结合手动和自动步骤的分割方法测量下丘脑体积。总体而言，肥胖参与者的下丘脑体积描述性较小，尽管这种差异没有达到统计学意义；然而，在肥胖参与者中，女性的下丘脑体积明显小于男性。胰岛素抵抗和性别对下丘脑体积有显著的交互作用；存在显著胰岛素抵抗的肥胖女性的下丘脑体积小于肥胖男性。肥胖青少年的循环 CRP 和神经营养因子水平较高。此外，在肥胖女性中，BDNF 浓度与下丘脑体积呈负相关（r = -0.48）。鉴于肥胖胰岛素抵抗女性的 BDNF 和下丘脑体积之间存在这种负相关，神经营养因子水平升高可能表明存在保护性代偿的尝试。
