Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São PauloAvenueBandeirantes, 3900, Monte Alegre, 14049-900, Ribeirão Preto, SP, Brazil.
Stress. 2011 May;14(3):290-300. doi: 10.3109/10253890.2010.545459. Epub 2011 Mar 28.
Experimental and clinical evidence shows that neutrophils play an important role in the mechanism of tissue injury in immune complex diseases through the generation of reactive oxygen species. In this study, we examined the influence of academic psychological stress in post-graduate students on the capacity of their blood neutrophils to release superoxide when stimulated by immune complexes bound to nonphagocytosable surfaces and investigated the modulatory effect of cortisol on this immune function. The tests were performed on the day before the final examination. The state-trait anxiety inventory questionnaire was used to examine whether this stressful event caused emotional distress. In our study, the psychological stress not only increased plasma cortisol concentration, but it also provoked a reduction in superoxide release by neutrophils. This decrease in superoxide release was accompanied by diminished mRNA expression for subunit p47(phox) of the phagocyte superoxide-generating nicotinamide adenine dinucleotide phosphate-oxidase. These inhibitory effects were also observed by in vitro exposure of neutrophils from control volunteers to 10(- 7) M hydrocortisone, and could be prevented by the glucocorticoid receptor antagonist RU-486. These results show that in a situation of psychological stress, the increased levels of cortisol could inhibit superoxide release by neutrophils stimulated by IgG immune complexes bound to nonphagocytosable surfaces, which could attenuate the inflammatory state.
实验和临床证据表明，中性粒细胞通过产生活性氧在免疫复合物疾病的组织损伤机制中发挥重要作用。在这项研究中，我们研究了研究生在学术心理压力下对其血液中性粒细胞在受到与非吞噬表面结合的免疫复合物刺激时释放超氧化物的能力的影响，并研究了皮质醇对这种免疫功能的调节作用。这些测试是在期末考试前一天进行的。使用状态-特质焦虑量表问卷检查这种有压力的事件是否引起了情绪困扰。在我们的研究中，心理压力不仅增加了血浆皮质醇浓度，而且还引发了中性粒细胞中超氧化物释放的减少。这种超氧化物释放的减少伴随着吞噬细胞超氧化物生成烟酰胺腺嘌呤二核苷酸磷酸氧化酶亚基 p47(phox)的 mRNA 表达减少。通过体外将来自对照志愿者的中性粒细胞暴露于 10(-7)M 氢化可的松，也可以观察到这种抑制作用，并且可以通过糖皮质激素受体拮抗剂 RU-486 来预防。这些结果表明，在心理压力的情况下，增加的皮质醇水平可以抑制与非吞噬表面结合的 IgG 免疫复合物刺激的中性粒细胞中超氧化物的释放，从而减轻炎症状态。
