Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, USA.
Professor Emeritus, Department of Psychology, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, USA.
J Neurol. 2017 Sep;264(9):2027-2030. doi: 10.1007/s00415-017-8588-7. Epub 2017 Aug 14.
The gut with its variety of microbiota may serve as an etiological origin of diseases. Gut microbes may also play a role in the pathogenesis of diseases beyond their simple nutritional maintenance and support. For example, gut protein aggregation, possibly aided by microbes as well as nasal influences, might be linked to disease that may move to the brain through the vagus nerve. To this end, Braak has offered a "dual-hit" hypothesis that proposes a novel etiology for Parkinson's disease (PD). The hypothesis places the initial origin of the disease in the nose and the gastrointestinal tract (GI) after infection by an unknown pathogen that could aggregate in the gut and then eventually spread to the brain via the autonomic plexuses. Gut health functioning, therefore, may affect brain status and behavior. A protein known as alpha-synuclein accumulates in brains of people with Parkinson's disease that is also present in the GI before the onset of motor symptoms. Therefore, the stomach, previously thought to be a stable mechanism throughout life, might explain some etiological origins of disease. Finally, the vagus nerve of the autonomic system that extends from the brain to the abdomen and exercises both sympathetic and parasympathetic roles might be associated with PD diagnosis along with Lewy body influences.
肠道及其多样化的微生物群可能是疾病的病因起源。肠道微生物也可能在疾病的发病机制中发挥作用，而不仅仅是简单的营养维持和支持。例如，肠道蛋白聚集，可能是由微生物和鼻腔影响共同作用的结果，可能与通过迷走神经转移到大脑的疾病有关。为此，Braak 提出了一个“双重打击”假说，为帕金森病 (PD) 提出了一种新的病因。该假说将疾病的最初起源定位于感染未知病原体后的鼻腔和胃肠道 (GI)，该病原体可能在肠道中聚集，然后通过自主神经丛最终传播到大脑。因此，肠道健康功能可能会影响大脑状态和行为。一种称为α-突触核蛋白的蛋白质在帕金森病患者的大脑中积累，在运动症状出现之前也存在于胃肠道中。因此，以前被认为是一生中稳定机制的胃可能可以解释一些疾病的病因起源。最后，自主神经系统的迷走神经从大脑延伸到腹部，行使交感和副交感作用，可能与 PD 诊断以及路易体影响有关。
