Brain mast cells and Chronic Fatigue Syndrome

描述(申请人提供)：慢性疲劳综合征(CFS)是一种复杂的疾病，患病率高达1%。CFS涉及神经、激素和免疫系统，症状包括疲劳、睡眠障碍、不适、肌肉疼痛、偏头痛、胃肠道不适和认知问题。CFS患者可能存在线粒体“功能障碍”。许多CFS患者表现出异常的下丘脑-垂体-肾上腺(HPA)轴活动，而应激会加重症状。病毒感染或其他炎性刺激产生的中枢和外周细胞因子可能与此有关，但没有明显的模式。CFS通常与其他疾病并存，包括纤维肌痛、间质性膀胱炎(1C)、肠易激综合征(IBS)、偏头痛和创伤后应激障碍。CFS的神经免疫相互作用尚不清楚，造成了诊断和治疗的真空。肥大细胞及其介体参与了所有与CFS并存的疾病。大脑正中隆起内有丰富的肥大细胞，它们与促肾上腺皮质激素释放激素(CRH)阳性神经元并列，CRH在应激状态下分泌，我们发现CRH通过CRHR-1激活肥大细胞，导致血管内皮生长因子(VEGF)释放，血管通透性增加和血脑屏障(BBB)破坏。我们最近发现，线粒体解偶联蛋白2(UCP2)的表达与肥大细胞的激活之间存在负相关关系，UCP2也调节着活性氧物种(ROS)和胞浆钙的产生。对于CFS，目前还没有有效的治疗方法。三环类抗抑郁药已被报道是有益的，我们的初步结果表明，只有三环类阿米替林和某些天然类黄酮才能抑制肥大细胞的分泌，降低细胞内钙离子水平。我们的假设是，外部刺激与应激分泌的CRH一起激活间脑中枢和肥大细胞，导致促炎和疲劳产生分子的释放，这些分子可以被选定的黄酮类化合物抑制。我们将研究：(1)CRH、病毒多聚(L：C)、脂多糖、神经降压素(NT)、P物质(SP)和胸腺基质淋巴生成素(TSMP)或束缚应激对C57BL/6雌性小鼠的影响：(A)通过强迫水浸试验引起疲劳；(B)通过检测脑内荧光标记物AngioSense的水平，以及(C)脑内组氨酸脱羧酶(HDC)、CRN、β-内啡肽、IL-6、IL-8、IL-17、生长抑素、肿瘤坏死因子、皮质醇、小鼠肥大细胞蛋白(MMCP)、肿瘤坏死因子(Corurotin)、皮质醇(Corurotin)的水平，以及(C)脑内组氨酸脱羧酶(HDC)、CRN、β-内啡肽、IL-6、IL-8、IL-17、生长抑素、皮质醇、小鼠肥大细胞蛋白(MMCP)、肿瘤坏死因子(Corurotin)、皮质醇(Corurotin)的水平，以及(C)脑组织组氨酸脱羧酶(HDC)、CRN、β-内啡肽、IL-6、IL-8、IL-17、生长抑素、皮质醇、小鼠肥大细胞蛋白(MMCP)、肿瘤坏死因子(Corurotin)、皮质醇(Corurotin)的水平，以及(C)脑组织组氨酸脱羧酶(HDC)、CRUCP2和血管内皮生长因子；(2)对肥大细胞的需求、对NT、SP、CRHR的参与以及UCP2在目标1中通过C57BL来源的WW肥大细胞缺陷小鼠、NT-/-小鼠、SP-/-小鼠、CRHR-1、CRHR-2-/-和UCP2-/-小鼠的作用进行了研究；(3)含有木犀草素/栎素/橄榄仁油的黄酮类制剂对耐力和脑生物标志物的抑制作用。这项拟议的研究是假设驱动的，基于强有力的初步证据，具有创新性，新发现适用于人类的可能性很高。 公共卫生意义：慢性疲劳综合征(CFS)是一种神经免疫内分泌紊乱，目前尚无确切的发病机制或治疗方法。最近的证据表明，CFS可能与一种独特的免疫细胞-肥大细胞的激活有关，肥大细胞可以破坏肠道-血-脑屏障，导致脑部炎症和导致疲劳的分子的释放。这项拟议的研究有望促进我们对大脑肥大细胞激活如何促进炎症和CFS的理解，以及开发新的有效治疗方法。

DESCRIPTION (provided by applicant): Chronic Fatigue Syndrome (CFS) is a complex disease with a prevalence as high as 1%. CFS involves the nervous, hormonal and immune systems with symptoms that include fatigue, sleep disturbances, malaise, muscle aches, migraines, gastrointestinal complaints and cognitive problems. There may be some mitochondrial "dysfunction" in CFS patients. Many CFS patients demonstrate abnormal hypothalamic-pituitary- adrenal (HPA) axis activity, while stress worsens symptoms. Central and peripheral cytokines produced in response to viral infections or other inflammatory stimuli may be implicated, but there is no distinct pattern. CFS is often comorbid with other disorders that include fibromyalgia, interstitial cystitis (1C), irritable bowel syndrome (IBS), migraines and post-traumatic stress disorder. Neuroimmune interactions in CFS are still unknown creating a vacuum in diagnosis and treatment. Mast cells and their mediators have been implicated in all diseases that are comorbid with CFS. Brain mast cells are abundant in the median eminence where they are juxtaposed to corticotropin-releasing hormone (CRH)-positive neurons and CRH is secreted under stress and we showed that CRH activates mast cells through CRHR-1 leading to release of vascular endothelial growth factor (VEGF), increased vascular permeability and blood-brain-barrier (BBB) disruption. We recently showed an inverse relationship between expression of the mitochondrial uncoupling protein 2 (UCP2), which also regulates production of reactive oxygen species (ROS) and cytosolic calcium, and mast cell activation. There are no effective therapies for CFS. Tricyclic antidepressants have been reported to be beneficial, and our preliminary results indicate that only the tricyclic amitriptyline, and certain natural flavonoids can inhibit mast cell secretion and reduce intracellular calcium ion levels. Our hypothesis is that external triggers, along with CRH secreted by stress, activate diencephalic centers and mast cells, leading to release of proinflammatory and fatigue producing molecules, and these can be inhibited by select flavonoids. We will investigate: (1) the effect of CRH, viral poly(l:C), lipopolysaccharide (LPS), neurotensin (NT), substance P (SP) and thymus stromal lymphopoietin (TSMP) or restraint stress using female C57BL/6 mice on: (a) Fatigue using the forced water immersion test, (b) BBB disruption by measuring brain levels of the fluorescent marker AngioSense, as well as (c) Brain expression of histidine decarboxylase (HDC), CRN, beta-endorphin, IL-6, IL- 8, IL-17, somatostatin, TNF, mouse mast cell protease (MMCP), urocortin 2, UCP2 and VEGF; (2) The requirement for mast cells, for NT, SP, the CRHR involved, and the role of UCP2 in the endpoints studied in Aim 1 by using C57BL-derived WW mast cell deficient mice, NT -/- mice, SP -/- mice, CRHR-1; CRHR-2 -/- and UCP2 -/- mice, (3) Inhibitory effect of a flavonoid formulation containing luteolin/quercetin/olive kernel oil on endurance and brain biomarkers. The proposed research is hypothesis-driven, is based on strong preliminary evidence, is innovative with high likelihood for novel findings with applicability to humans. PUBLIC HEALTH RELEVANCE: Chronic Fatigue Syndrome (CFS) is neuroimmunoendocrine disorder with no definite pathogenesis or curative therapy presently available. Recent evidence suggests that CFS may be related to activation of a unique immune cell, the mast cell, which could disrupt gut-blood-brain barrier and lead to brain inflammation and release of fatigue causing molecules. The proposed research is expected to advance our understanding of how activation of brain mast cells can contribute to inflammation and CFS, as well as to the development of novel and effective treatments.