痛风代谢病肠道微生态及区域免疫特性研究

As a common disease, gout can lead to a series of complications such as diabetes, cardiovascular disease, uremia and so on, which have seriously affecting on people's health. Usually, clinical drugs for gout are working on uric acid metabolism of kidney, however, metabolism of uric acid in intestine has not been reported (about 1 / 3 of metabolism of uric acid is through the intestinal metabolism in vivo). Our previous study found that the intestinal flora have had significant changes in the gout group compared with the control group, which indicated that the intestinal flora had involved in the process of gout.This project intends to further studies of intestinal micro ecology and regional immune characteristic of gout metabolic disease: 1) Constructing models of diet-induced mice and uricase gene knock-out mice , detecting of blood biochemical indicators, planting isolated fecal flora in sterile mice and then analyzing gut microflora with 16S rDNA ; 2) Choosing typical patients with gout and detecting blood biochemical of clinical indicators ;Separating intestinal flora for analyzing gut micro ecological; 3) Detecting the structure and permeability in intestinal mucosa; analyzing immune cells and inflammatory factor variation using Q-PCR and other methods ;Our goal is to elucidate intestinal mechanism of gout pathogenesis through analyzing the relationship between intestinal microbiota and regional immunity basing on metabolomics analysis and microbiota study for lay the foundation of diet and intestinal treatment for gout patients.

痛风作为一种常见病，可引起糖尿病、心脑血管疾病、尿毒症等并发症，严重影响着人们健康。但目前治疗痛风的临床药物均是针对尿酸的肾脏代谢，而尿酸的肠道代谢尚未见报道（人体约1/3的尿酸是通过肠道代谢的）。课题组前期工作发现，与对照组相比，痛风组肠道菌群发生了显著变化，表明肠道菌群参与了痛风的发生过程。本项目拟进一步进行痛风代谢病肠道微生态及区域免疫特性研究：1）构建饮食诱导模型鼠和尿酸酶基因敲除鼠，检测血液生化等指标，分离粪便菌群并定植于无菌鼠中；然后利用16S rDNA测序进行肠道微生态分析；2）选取典型痛风患者，检测检测血生化等临床指标，分离粪便菌群进行肠道微生态分析；3）检测肠黏膜结构、肠渗透性等变化；利用荧光定量PCR等方法分析免疫细胞、炎症因子变化特征，结合肠道菌群研究，分析肠道菌群与肠道区域性免疫间的关系，明确痛风的肠道发病机制，为痛风的饮食调理和肠道治疗奠定基础。

痛风作为一种常见病，可引起糖尿病、心脑血管疾病、尿毒症等并发症，严重影响着人们健康。但目前治疗痛风的临床药物均是针对尿酸的肾脏代谢，而尿酸的肠道代谢尚未见报道（人体约1/3的尿酸是通过肠道代谢的）。本项目从已建立的的痛风病临床样本库中选择典型样本并且构建模型鼠，分析疾病相关肠道微生态和区域性免疫变化。研究显示，高血尿酸增加了系统性炎症反应，导致肠渗透性增加，血循环LPS增加，进而导致菌群及代谢产物移位。同时，系统循环中促炎症因子TNF-α显著增加，系统循环的LPS、菌群及炎症因子导致多种组织的炎症反应。而且我们研究显示，高血尿酸可能通过调控CYP450家族，影响肠道免疫反应。进一步，通过构建模型鼠和菌群移植实验，观察移植后受体大鼠变化情况，研究显示肠道菌群与疾病的发生密切相关，而且，高尿酸血症导致肠菌群紊乱和肠屏障损伤，Bacteroides, Alloprevotella及一些与肠炎症相关的菌群例如Alistipes 和 Parabacteroides显著增加，而一些产生丁酸盐的菌、有益菌及厌氧菌例如Clostridium 、Lactobacillus 、Candidatus 和Coriobacteriaceae明显减少。另外，高尿酸血症还导致了脂代谢紊乱。与正常小鼠相比，模型鼠中血清总胆固醇、低密度脂蛋白胆固醇和高密度脂蛋白胆固醇均显著增加，与脂肪酸代谢和胆固醇合成相关的基因发生了显著的变化，而且高血尿酸损伤了肝脏功能，进而破坏了肠肝循环，导致脂代谢紊乱。 这些研究均为痛风的饮食调理和肠道治疗奠定了基础。