Impact of dysbiosis on the development of age-related inflammation

项目摘要 “衰老的支柱”假说认为，慢性未解决的炎症，加上代谢 功能障碍和大分子损伤是损害细胞更新的关键机制， 导致衰老和慢性疾病的再生过程。炎症是一种保护机制 它已经进化到可以抵御病原体和组织损伤，使宿主能够在危及生命的情况下生存下来。 恢复体内平衡的挑战。那么像炎症这样的保护性反应是如何 慢性的，驱动老化和作为慢性疾病的触发器？在衰老过程中没有明显的感染， 肠道微生物群的改变（生态失调）或微生物群衍生的PAMP可能易位至肝脏， 肠系膜和网膜脂肪组织可能参与了年龄相关性炎症的机制。一致 有了这种可能性，最近的研究已经证明了微生物组的深刻变化， 这表明微生物组可能在炎症的某些方面发挥因果作用。我们最近 发现衰老与三级淋巴结构的形成有关，称为脂肪相关 内脏脂肪组织中的淋巴簇（PBMC）。与淋巴结不同， 与脂肪细胞相关的非包囊化非经典淋巴组织含有T细胞、B细胞和 巨噬细胞此外，我们发现，B细胞随着年龄的增长而扩大，并显示出独特的 转录谱使人联想到抗原经历的B细胞。根据我们最初的发现， 本申请假设是肠道微生物移位到内脏脂肪组织导致了CCLC 形成和年龄相关的炎症，导致代谢功能障碍。我们将测试 防止微生物群的移位防止了CD40C的形成和炎症。

PROJECT SUMMARY The “pillars of aging” hypothesis entails that chronic unresolved inflammation, coupled with metabolic dysfunction and macromolecular damage are among the key mechanisms that impairs cellular renewal and regenerative processes that contribute to aging and chronic diseases. Inflammation is a protective mechanism that has evolved to protect against pathogens and tissue injury that enables a host to survive life-threatening challenges by restoration of homeostasis. How then does a protective response like inflammation become chronic, drive aging and serve as a trigger of chronic disease? In absence of overt infections in aging, alterations in the gut microbiota (dysbiosis) or potential translocation of microbiota derived PAMPs to liver, mesenteric and omental adipose tissue could contribute to the mechanism of age-related inflammation. In line with this possibility, recent studies have demonstrated profound changes in the microbiome associated with aging and suggest that the microbiome may play a causal role in certain aspects of inflammaging. We recently discovered that aging is associated with formation of tertiary lymphoid structures, called Fat-associated lymphoid clusters (FALCs), in the visceral adipose tissue. The FALCs, unlike lymph nodes are disorganized non-encapsulated non-classical lymphoid tissues associated to adipocytes contain T cells, B cell and macrophages. Moreover, we found that B cells expand with age in the FALCs and display a unique transcriptional profile reminiscent of antigen-experienced B cells. Based on our original findings, the central hypothesis of this application is that translocation of gut microbes to visceral adipose tissue results in FALC formation and age-related inflammation leading to metabolic dysfunction. We will test the mechanism of how preventing the translocation of microbiota protects against FALC formation and inflammaging.