Warne James P
Diabetes Center, University of California San Francisco, 513 Parnassus Avenue, Box 0534, San Francisco, CA 94143-0534, USA.
Mol Cell Endocrinol. 2009 Mar 5;300(1-2):137-46. doi: 10.1016/j.mce.2008.09.036. Epub 2008 Oct 15.
Activity of the hypothalamo-pituitary-adrenal (HPA) axis is regulated by a negative feedback loop that dampens central drive of the axis via the actions of the secreted glucocorticoids. Conversely, under conditions of chronic stress, glucocorticoids delivered centrally increase hypothalamic paraventricular nucleus (PVN) corticotrophin-releasing factor (CRF) expression and the response to restraint. However, HPA axis activity and PVN CRF mRNA expression under chronic stress conditions are often reduced, implying other indirect peripheral or extra-hypothalamic glucocorticoid actions. Glucocorticoids chronically increase palatable food intake, which increases abdominal fat depots and circulating insulin levels, both of which negatively correlate with PVN CRF mRNA expression and may in turn dampen the response to stress. Such an effect is dependent on food choices, rather than total calories ingested. Considering stress is omnipresent in the workplace, palatable food ingestion may represent a means to combat the feeling of stress which is ultimately maladaptive when unresolved.
下丘脑 - 垂体 - 肾上腺(HPA)轴的活动受负反馈回路调节,该回路通过分泌的糖皮质激素的作用减弱轴的中枢驱动。相反,在慢性应激条件下,中枢给予的糖皮质激素会增加下丘脑室旁核(PVN)促肾上腺皮质激素释放因子(CRF)的表达以及对应激的反应。然而,慢性应激条件下HPA轴活动和PVN CRF mRNA表达通常会降低,这意味着存在其他间接的外周或下丘脑外糖皮质激素作用。长期使用糖皮质激素会增加美味食物的摄入量,这会增加腹部脂肪堆积和循环胰岛素水平,二者均与PVN CRF mRNA表达呈负相关,进而可能会减弱对应激的反应。这种影响取决于食物选择,而非摄入的总热量。考虑到工作场所中压力无处不在,摄入美味食物可能是一种应对压力感的方式,但如果压力得不到解决,这种方式最终会适得其反。