The role of advanced glycation end products in modulating healthspan using C. elegans

总结 衰老和高血糖导致一系列反应性α-二羰基化合物（α-DCs， 例如乙二醛/GO、甲基乙二醛/MGO、3-脱氧葡萄糖醛酮/3DG）和α-DC衍生的代谢产物，称为晚期代谢产物 糖基化终产物（AGEs）。AGEs的形成是由于α-DCs与蛋白质、脂质和DNA反应， 细胞应激与特定的年龄相关过程、糖尿病并发症和神经变性有关。 因此，防止α-DC和AGE的积累对于减缓衰老和限制衰老具有至关重要的意义。 各种与年龄有关的疾病。理解生物化学背后的一个主要瓶颈是 这些并发症的进展，以及因此快速的药物开发，是缺乏遗传上易处理的 可以概括α-DC和AGE在短时间内蓄积的作用的模型。为此我们 建立了一个基于受损的谷胱甘肽酶基因的秀丽隐杆线虫模型来研究α-DC， 与年龄有关的疾病。这些动物表现出几种让人联想到糖尿病并发症的表型，例如 MGO和AGEs的积累，以及感觉过敏（或对触摸过敏），在两周内， 成年最有趣的是，它们表现出与年龄相关的神经元损伤增加和寿命缩短。 使用这个模型，我们已经确定了TRPA-1的关键作用，TRPA-1是一种瞬时受体电位（TRP）通道， 感测MGO并激活Nrf 2（核因子红细胞样-2，或NFE 2L 2）以抵消 年龄使用该模型进行的初步药物筛选产生了2种有希望的化合物， C. elegans通过TRPA-1/SKN-1激活。我们建议使用C。优雅作为一个 无脊椎动物模型来研究AGE在两周内积累的影响，这可能需要数年的时间来发展 在人类中，允许快速发现与衰老和年龄相关的遗传和药理学靶点 AGEs发挥重要作用的疾病。 在这项建议中，我们将：1）表征TRPA-1/ SKN-1在遗传和细胞凋亡中的作用， 2）表征介导α-DC解毒的SKN-1下游的糖苷酶 和3）使用以下方法检查TRPA-1/SKN-1途径在哺乳动物中解毒MGO中的保守性： 人类神经细胞这些目标将有助于破译α-DC解毒网络， 本发明提供了可以减轻糖尿病并发症并延长糖尿病患者的健康寿命的治疗靶点和新型化合物， 糖尿病人

Summary Aging and hyperglycemia results in an accumulation of a series of reactive α-dicarbonyl compounds (α-DCs, e.g. glyoxal/GO, methylglyoxal/MGO, 3-deoxyglucosone/3DG) and α-DC-derived metabolites, called advanced glycation end products (AGEs). AGEs form due to the reaction of α-DCs with proteins, lipids, and DNA causing cellular stress linked with specific age-related processes, diabetic complications and neurodegeneration. Therefore, preventing α-DC and AGE buildup is of quintessential importance for slowing aging and limiting the progression of various age-related diseases. A major bottleneck in understanding the biochemistry behind the progression of these complications, and hence rapid drug development, is the lack of genetically tractable models that can recapitulate the effects of α-DC and AGE accumulation in a short time frame. To that end, we have established a Caenorhabditis elegans model based on an impaired glyoxalase gene to study α-DC and AGE-related pathologies. These animals exhibit several phenotypes reminiscent of diabetic complications, such as accumulation of MGO and AGEs, and hyperesthesia (or hyper sensitivity to touch), within two weeks of adulthood. Most interestingly they demonstrate increased age-related neuronal damage and shortened lifespan. Using this model we have identified a critical role for TRPA-1, a transient receptor potential (TRP) channel in sensing MGO and activating Nrf2 (Nuclear factor erythroid-2 like 2, or NFE2L2) to counteract the effects of AGEs. A preliminary drug screen using this model has resulted in 2 promising compounds that can ameliorate AGE-related pathologies in C. elegans through TRPA-1/SKN-1 activation. We propose to use C. elegans as an invertebrate model to study the effects of AGE accumulation within two weeks which can take years to develop in humans, to allow rapid discovery of genetic and pharmacological targets relevant to aging and age-related diseases where AGEs play an important role. In this proposal we will: 1) Characterize the role of TRPA-1/ SKN-1 both genetically and pharmacologically in detoxifying MGO; 2) Characterize the glyoxalases downstream of SKN-1 that mediate detoxification of α-DCs like MGO and 3) examine the conservation of the TRPA-1/SKN-1 pathway in detoxifying MGO in mammals using human neuronal cells. Together these aims will help to decipher the α-DC detoxification network and identify therapeutic targets and novel compounds that can mitigate diabetic complications and extend healthspan of diabetics.