Role of Neuroendocrine Stress Response in Inflammatory and Behavioral Illness.

项目I：汗斑生物标记物：临床研究。在2009财年，我们发现神经和免疫生物标记物可以在汗液中检测到，并与临床缓解期患有严重抑郁障碍(MDD)的女性的血浆水平密切相关(5)。尤其是促炎细胞因子升高，交感神经肽Y(NPY)和感觉/疼痛相关神经肽P物质(SP)和降钙素基因相关肽(CGRP)升高，而副交感神经肽血管活性肠肽(VIP)显著降低。这一模式与MDD从副交感音调向交感音调的转变以及潜在的促炎状态一致，这可能是MDD对已知与MDD共同表达的疾病的易感性增加的原因，包括心血管疾病、骨质疏松症和糖尿病。此外，生物标记物水平与抑郁和焦虑症状密切相关，表明这些生物标记物的功能意义。为了确定特定生物标记物特征反映特定疾病或健康状况的程度，在2009财年，我们与其他NIH研究所和校外机构合作，在五个正在进行的IRB批准的临床方案中应用汗片生物标记物，包括：(I)埃默里大学TRD-Infliximab研究。(Ii)巴西--强迫症研究(NIH IRB 3737号议定书)；(3)Emory/CDC CFS研究(Emory University IRB 000551-2005年，NIMH OHSR豁免#4026)；(Iv)NCCAM--太极/癌症幸存者研究(NCI#06-AT-0016)；(V)GSA--工作环境研究(NIA IRB 2003-142)。 项目II总结：糖皮质激素抵抗、炎症和行为的动物模型：在我们评估孕酮对免疫细胞(DC)功能和成熟的影响以及女性性激素在宿主防御中的作用的研究中，我们发现非妊娠相关浓度的孕酮通过孕酮受体(PR)介导的机制抑制成熟DC产生促炎细胞因子、细胞表面标志表达(共刺激分子和趋化因子受体)和刺激T细胞增殖，但对未成熟DC抗原摄取几乎没有影响(2-4)。这些效应可与糖皮质激素对DC功能的影响相媲美，表明孕酮在调节女性的先天免疫和获得性免疫中起重要作用。在2009财年，我们发现孕酮对DC功能的影响在啮齿动物的动情周期中是不同的，并且依赖于PR的表达，在体外和体内的整个周期中，PR的表达是不同的，并且对不同组织的DC也有不同的影响。这表明，在整个发情周期中，女性的免疫反应在生理上是不同的，这对在发情周期和妊娠期间对感染和炎症的临床易感性具有重要的意义。荷尔蒙状态的这种生理波动也可能影响对情绪起作用的细胞反应。由于已知细胞因子可以影响情绪，并可能在某些形式的抑郁症以及疾病行为中的情绪变化中发挥作用，孕酮等因素可以改变细胞产生的细胞因子，从而导致女性在整个生命周期中对情绪障碍的不同易感性。在我们的细菌毒素研究中，我们发现了通过MAPK(丝裂原活化蛋白激酶)失活的细菌毒素，诱导包括GR和PR(8)在内的核激素受体(NHR)的部分抑制。这些毒素包括炭疽芽孢杆菌致死毒素(LeTx)、索氏梭状芽孢杆菌致死毒素(TcsL)和艰难梭菌毒素A(TcdA)和毒素B(TcdB)。我们在2009财年的研究表明，细菌毒素NHR的抑制既依赖于受体，也依赖于启动子，并与其他转录因子的抑制有关(6)。初步证据表明，毒素的作用是通过对GR的翻译后修饰来实现的。这些毒素可以为研究诱导糖皮质激素抵抗对多种生理系统的影响提供工具。

PROJECT I. Sweat Patch Biomarkers: Clinical Studies. In FY 2009, we showed that neural and immune biomarkers are detectable in sweat and strongly correlate with plasma levels in a group of women with major depressive disorder (MDD) in clinical remission (5). Specifically, pro-inflammatory cytokines were elevated, as was the sympathetic neuropeptide neuropeptide Y (NPY) and the sensory/pain-related neuropeptides, substance P (SP) and CGRP (calcitonin gene-related peptide), while the parasympathetic neuropeptide vasoactive intestinal polypeptide (VIP) was significantly decreased. This pattern is consistent with a shift in MDD from parasympathetic to sympathetic tone, and an underlying pro-inflammatory state that could account for enhanced susceptibility to conditions known to be co-morbidly expressed with MDD, including cardiovascular disease, osteoporosis and diabetes. Moreover, biomarker levels strongly correlated with symptoms of depression and anxiety, indicating functional significance of these biomarker profiles. In order to determine the extent to which particular biomarker profiles reflect specific diseases or a state of health, in FY09 we are applying sweat patch biomarkers in five ongoing IRB approved clinical protocols in collaboration with other NIH institutes and extramural insitutions, including: (i) Emory University TRD-Infliximab Study. (Emory University IRB 00011734, NIMH OHSR Exemption #4025); (ii) Brazil - OCD Study (NIH protocol IRB 3737); (iii) Emory/CDC CFS Study (Emory University IRB 000551-2005, NIMH OHSR Exemption #4026); (iv) NCCAM - Tai Chi/Cancer Survivor Study (NCI protocol #06-AT-0016); (v) GSA - Work Environment Study (NIA IRB 2003-142). Project II Summary: Animal Models of Glucocorticoid Resistance, Inflammation and Behavior: In our studies evaluating the effects of progesterone on immune cell (dendritic cell, DC) function and maturation and the role of female sex hormones in host defense, we found that progesterone in non-pregnancy-associated concentrations and through a progesterone receptor (PR)-mediated mechanism suppresses mature DC production of pro-inflammatory cytokines, cell surface marker expression (co-stimulatory molecules and chemokine receptors) and stimulation of T cell proliferation, but has little effect on immature DC antigen uptake (2-4). These effects, which are comparable to those of glucocorticoids on DC function, indicate that progesterone plays an important role in regulation of innate and adaptive immunity in females. In FY09 we found that progesterone effects on DC function vary throughout the rodent estrus cycle and are dependent on PR expression, which varies throughout the cycle in vitro and in vivo, and also differentially affects DCs from different tissues. This indicates that females immune responses vary physiologically throughout the estrus cycle, and has important implications for clinical susceptibility to infection and inflammation during the cycle and during pregnancy. Such physiological fluctuations in hormone status could also impact cellular responses that play a role in mood. Since cytokines are known to affect mood, and may play a role in some forms of depression as well as in mood alterations in sickness behavior, factors such as progesterone, which alter cytokine production by cells could contribute to differential mood disorder susceptibilities in females throughout the life cycle. In our bacterial toxin studies we identified bacterial toxins that through inactivation of the MAPK (mitogen-activated protein kinase), pathways, induce partial repression of nuclear hormone receptors (NHRs), including GR and PR (8). These toxins include Bacillus anthracis lethal toxin (LeTx), Clostridium sordellii lethal toxin (TcsL) and the C. difficile toxins, toxin A (TcdA) and B (TcdB). Our studies in FY09 indicate that bacterial toxin NHR repression is both receptor and promoter-dependent and is associated with the repression of other transcription factors (6). Preliminary evidence suggests that the toxins' effects are mediated through post-translational modifications to GR. These toxins could provide a tool to study the effects of induced glucocorticoid resistance on a variety of physiological systems.