Institute for Diabetes, Obesity and Metabolism and the Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA, 19104, USA.
Department of Surgery, University of Michigan, 2800 Plymouth Road, Ann Arbor, MI, 48109, USA.
Mol Metab. 2017 May 15;6(7):748-759. doi: 10.1016/j.molmet.2017.05.006. eCollection 2017 Jul.
Adult obesity risk is influenced by alterations to fetal and neonatal environments. Modifying neonatal gut or neurohormone signaling pathways can have negative metabolic consequences in adulthood. Here we characterize the effect of neonatal activation of glucagon like peptide-1 (GLP-1) receptor (GLP1R) signaling on adult adiposity and metabolism.
Wild type C57BL/6 mice were injected with 1 nmol/kg Exendin-4 (Ex-4), a GLP1R agonist, for 6 consecutive days after birth. Growth, body composition, serum analysis, energy expenditure, food intake, and brain and fat pad histology and gene expression were assessed at multiple time points through 42 weeks. Similar analyses were conducted in a conditional allele crossed with a Sim1Cre deleter strain to produce Sim1Cre;Glp1r mice and control littermates.
Neonatal administration of Ex-4 reduced adult body weight and fat mass, increased energy expenditure, and conferred protection from diet-induced obesity in female mice. This was associated with induction of brown adipose genes and increased noradrenergic fiber density in parametrial white adipose tissue (WAT). We further observed durable alterations in orexigenic and anorexigenic projections to the paraventricular hypothalamic nucleus (PVH). Genetic deletion of Glp1r in the PVH by Sim1-Cre abrogated the impact of neonatal Ex-4 on adult body weight, WAT browning, and hypothalamic architecture.
These observations suggest that the acute activation of GLP1R in neonates durably alters hypothalamic architecture to limit adult weight gain and adiposity, identifying GLP1R as a therapeutic target for obesity prevention.
成人肥胖风险受胎儿和新生儿环境改变的影响。改变新生儿肠道或神经激素信号通路可能会对成年后的代谢产生负面影响。在此,我们描述了新生儿激活胰高血糖素样肽-1(GLP-1)受体(GLP1R)信号对成年肥胖和代谢的影响。
对出生后连续 6 天每天给予 1 纳摩尔/千克 Exendin-4(Ex-4)的野生型 C57BL/6 小鼠进行处理。在 42 周的时间内,通过多个时间点评估生长、身体成分、血清分析、能量消耗、食物摄入以及大脑和脂肪垫组织学和基因表达。在与 Sim1Cre 缺失株杂交的条件性等位基因中进行了类似的分析,以产生 Sim1Cre;Glp1r 小鼠和对照同窝仔。
新生期给予 Ex-4 可降低雌性小鼠的成年体重和脂肪量,增加能量消耗,并防止肥胖饮食引起的肥胖。这与褐色脂肪基因的诱导和 parametrial 白色脂肪组织(WAT)中去甲肾上腺素纤维密度的增加有关。我们还观察到对室旁下丘脑核(PVH)的食欲刺激和厌食性投射的持久改变。Sim1-Cre 对 PVH 中的 Glp1r 进行基因缺失,削弱了新生期 Ex-4 对成年体重、WAT 褐变和下丘脑结构的影响。
这些观察结果表明,新生儿期 GLP1R 的急性激活可持久改变下丘脑结构,以限制成年体重增加和肥胖,确定 GLP1R 为肥胖预防的治疗靶点。