Department of Psychology, University of Illinois-Urbana Champaign, Champaign, Illinois.
Food Science and Human Nutrition, University of Illinois-Urbana Champaign, Champaign, Illinois.
Am J Physiol Regul Integr Comp Physiol. 2020 Mar 1;318(3):R515-R528. doi: 10.1152/ajpregu.00288.2019. Epub 2020 Jan 15.
The simultaneous introduction of wheel running (WR) and diet choice (high-carbohydrate chow vs. high-fat diet) results in sex-specific diet choice patterns in rats. WR induces a high-fat (HF) diet avoidance, and such avoidance persists in the majority of males, but not females, throughout a 2-wk period. Exercise is a physiological stressor that activates the hypothalamic-pituitary-adrenal (HPA) axis and stimulates glucocorticoid (GC) release, which can alter dietary preferences. Here, we examined the role of the HPA axis and GC signaling in mediating exercise-induced changes in diet preference and the associated neurobiological adaptations that may underlie sex differences in diet choice patterns. revealed that adrenalectomy did not significantly alter the initiation and persistence of running-induced HF diet avoidance in male rats. showed that acute WR resulted in greater neural activation than chronic WR in the medial prefrontal (mPFC) and insular cortices (IC) in male rats. revealed sex differences in the molecular adaptation to exercise and diet preference. First, exercise increased gene expression of in the mPFC, IC, and hippocampus of WR females but had limited influence in males. Second, male and female WR rats that reversed or maintained HF diet avoidance showed distinct sex- and HF diet preference-dependent expression profiles of genes involved in cortical GC signaling (e.g., , , and ). Taken together, our results suggest sex differences in region-specific neural adaptations may underlie sex differences in diet preference and the health benefits from exercise.
同时引入轮式跑步（WR）和饮食选择（高碳水化合物饲料与高脂肪饮食）会导致大鼠出现性别特异性的饮食选择模式。WR 会导致大鼠回避高脂肪（HF）饮食，而这种回避在大多数雄性大鼠中持续存在，但在大多数雌性大鼠中则不会，持续时间为 2 周。运动是一种生理应激源，会激活下丘脑-垂体-肾上腺（HPA）轴并刺激糖皮质激素（GC）释放，从而改变饮食偏好。在这里，我们研究了 HPA 轴和 GC 信号在介导运动引起的饮食偏好变化以及可能导致饮食选择模式性别差异的相关神经生物学适应中的作用。结果表明，肾上腺切除术并没有显著改变雄性大鼠开始和持续回避 HF 饮食的跑步诱导作用。结果表明，急性 WR 导致雄性大鼠的内侧前额叶皮质（mPFC）和岛叶皮质（IC）的神经激活比慢性 WR 更大。结果还揭示了运动和饮食偏好的分子适应中的性别差异。首先，运动增加了雌性 WR 大鼠 mPFC、IC 和海马体中基因的表达，但对雄性大鼠的影响有限。其次，逆转或维持 HF 饮食回避的雄性和雌性 WR 大鼠表现出涉及皮质 GC 信号的基因表达的明显性别和 HF 饮食偏好依赖性特征（例如， 、 、和 ）。总之，我们的结果表明，特定区域的神经适应中的性别差异可能是饮食偏好和运动带来的健康益处的性别差异的基础。
