Gut Dysbiosis and Cerebral Small Vessel Disease

肠道菌群失调和脑小血管疾病

• 批准号: 10200157
• 负责人: ROBERT M BRYAN
• 金额: $ 40.03万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10200157
• 关键词: Affect; Animal Diseases; Animal Model; Antibiotics; Antigens; Attention; Attenuated; Bacteria; Bacterial DNA; Bacterial RNA; Bacterial Translocation; Blood; Blood - brain barrier anatomy; Brain; Brain Pathology; Cardiovascular Diseases; Cecum; Cerebral small vessel disease; Cerebrovascular Disorders; Cerebrum; Characteristics; DNA; Data; Development; Disease; Distal; Encephalitis; Endotoxins; Engineering; Equilibrium; Feces; Fluorescent in Situ Hybridization; Fostering; Gastrointestinal tract structure; Gram-Negative Bacteria; Hypertension; Impaired cognition; Inbred WKY Rats; Inflammation; Label; Lacunar Infarctions; Lipopolysaccharides; Location; Measures; Microaneurysm; Microbe; Modeling; Movement; Names; National Institute of Neurological Disorders and Stroke; Parents; Pathologic; Pathology; Peptidoglycan; Phenotype; Probiotics; Process; Rattus; Reporter; Reverse Transcriptase Polymerase Chain Reaction; Source; Stroke; Symptoms; Taxonomy; Testing; Therapeutic Intervention; arteriole; brain health; dysbiosis; gastrointestinal epithelium; gray matter; gut bacteria; gut dysbiosis; gut microbiome; gut microbiota; microbiome; novel; nursing mothers; prevent; pup; rRNA Genes; targeted treatment; white matter

Cerebral small vessel disease (CSVD), a recognized priority established by the NINDS, is a major cause of cognitive impairment. In this proposal, we present the novel idea that antigens derived from the gut microbiota constitute a fundamental source for the inflammation underlying CSVD. We propose that gut dysbiosis allows bacteria and bacterial components to translocate the gut epithelial barrier and ultimately gain access to the brain where they initiate and maintain inflammation necessary for the development of CSVD. The hypothesis is supported with strong preliminary data: (1) gut dysbiosis occurs in spontaneously hypertensive stroke-prone rats (SHRSP), a relevant model for CSVD, compared to its parent strain, WKY rats; (2) altering the gut microbiome in WKY rats to resemble that of SHRSP is accompanied by pathological changes occurring in SHRSP. Altering the gut microbiome in SHRSP rats to resemble that of WKY rats attenuates these pathological changes; (3) brains of SHRSP contain 52% more bacterial DNA than WKY rats; (4) gram-negative bacteria represent a substantially greater proportion of the overall bacterial DNA in brains of SHRSP compared to WKY rats; and (5) lipopolysaccharides (LPS), bacterial endotoxin derived from gram negative bacteria, are substantially increased in brains of SHRSP compared to WKY rats. In Specific Aim 1 we will determine if CSVD can be produced or prevented through manipulation of the gut microbiota. If gut dysbiosis is an underlying cause of CSVD then we should be able to induce CSVD in control WKY rats, the parent strain for the SHRSP, by inducing dysbiosis. Alternatively, we should be able to abolish or delay the onset of CSVD in SHRSP rats by preventing dysbiosis. In Specific Aim 2 we will identify gut and brain bacteria and bacterial components involved with the initiation of CSVD. (a) We will analyze the bacterial DNA composition of the gut and brain by sequencing the bacterial 16s rRNA gene from feces, cecal content, and brain. Using targeted qPCR, we will further identify bacteria to the species level. (b) We will determine if intact bacteria are resident in the brain using RT-PCR and fluorescence in situ hybridization of SHRSP and WKY rats. In Specific Aim 3 we propose to track the movement of bacteria and bacterial components, a process termed translocation, from the gut to the brain. First, we will determine if fluorescently labeled LPS and peptidoglycan track to the brain when gavaged into the gut of SHRSP and WKY rats. Second, we will employ bacteria that we have engineered with reporters to track bacteria from gut to brain and determine if gram- negative bacteria are capable of translocating from gut to brain more efficiently in hosts developing CSVD. If our hypothesis is valid, then the gastrointestinal tract (GI) can affect the health of the brain. Establishing the gut microbiome as a source for inflammation related to CSVD could dramatically refocus our attention on the GI tract as a potential cause for brain pathologies, as well as provide a target for therapeutic intervention.

大脑小血管疾病（CSVD）是Ninds确立的公认优先级，是造成的主要原因 认知障碍。在此提案中，我们提出了一种新颖的想法，即抗原源自肠道菌群 构成CSVD炎症的基本来源。我们提出肠道营养不良 允许细菌和细菌成分易位肠道上皮屏障并最终获得 进入他们发起并维持开发必要的炎症的大脑 CSVD。该假设得到了强有力的初步数据支持：（1）肠道营养不良发生自发发生 与母体菌株WKY大鼠相比，高血压折叠式中风大鼠（SHRSP）是CSVD的相关模型。 （2）改变WKY大鼠中的肠道微生物组以类似于SHRSP SHRSP中发生的变化。改变SHRSP大鼠中的肠道微生物组，以类似于WKY大鼠 减弱这些病理变化； （3）SHRSP的大脑含有比WKY大鼠多52％的细菌DNA； （4）革兰氏阴性细菌在大脑中的总体细菌DNA比例更大。 SHRSP与WKY大鼠相比； （5）脂多糖（LPS），衍生自克的细菌内毒素 与WKY大鼠相比，SHRSP的大脑的阴性细菌大大增加。在特定的目标1中我们 将通过操纵肠道菌群来确定是否可以生产或阻止CSVD。如果肠道 营养不良是CSVD的根本原因，那么我们应该能够在控制WKY大鼠中诱导CSVD， SHRSP的父菌株，通过诱导营养不良。另外，我们应该能够废除或延迟 SHRSP大鼠CSVD的发作通过预防营养不良。在特定目标2中，我们将识别肠道和脑细菌 和与CSVD启动有关的细菌成分。 （a）我们将分析细菌DNA 通过从粪便，盲肠含量和 脑。使用靶向QPCR，我们将进一步识别细菌至物种水平。 （b）我们将确定是否完整 细菌使用RT-PCR驻留在大脑中，SHRSP和WKY的荧光原位杂交 老鼠。在特定目标3中，我们建议跟踪细菌和细菌成分的运动，这是一个过程 被称为易位，从肠道到大脑。首先，我们将确定荧光标记的LP和 肽聚糖轨道伸入SHRSP和WKY大鼠的肠道时，向大脑轨道。第二，我们将雇用 我们已经与记者一起设计的细菌以跟踪从肠道到大脑的细菌，并确定是否gram- 阴性细菌能够在开发CSVD的宿主中更有效地从肠道转移到大脑。如果 我们的假设是有效的，然后胃肠道（GI）会影响大脑的健康。建立肠道 微生物组作为与CSVD相关的炎症来源可能会极大地重新关注GI 道作为脑病理的潜在原因，并为治疗干预提供了目标。