Center for Advanced Vision Science, University of Virginia School of Medicine, Charlottesville, VA, USA.
Department of Ophthalmology, University of Virginia School of Medicine, Charlottesville, VA, USA.
Signal Transduct Target Ther. 2021 Apr 14;6(1):149. doi: 10.1038/s41392-021-00537-z.
Nonfibrillar amyloid-β oligomers (AβOs) are a major component of drusen, the sub-retinal pigmented epithelium (RPE) extracellular deposits characteristic of age-related macular degeneration (AMD), a common cause of global blindness. We report that AβOs induce RPE degeneration, a clinical hallmark of geographic atrophy (GA), a vision-threatening late stage of AMD that is currently untreatable. We demonstrate that AβOs induce activation of the NLRP3 inflammasome in the mouse RPE in vivo and that RPE expression of the purinergic ATP receptor P2RX7, an upstream mediator of NLRP3 inflammasome activation, is required for AβO-induced RPE degeneration. Two classes of small molecule inflammasome inhibitors-nucleoside reverse transcriptase inhibitors (NRTIs) and their antiretrovirally inert modified analog Kamuvudines-both inhibit AβOs-induced RPE degeneration. These findings crystallize the importance of P2RX7 and NLRP3 in a disease-relevant model of AMD and identify inflammasome inhibitors as potential treatments for GA.
非纤维状淀粉样蛋白-β 寡聚体(AβOs)是老年黄斑变性(AMD)的特征性视网膜色素上皮下(RPE)细胞外沉积物——玻璃膜疣的主要成分,AMD 是一种常见的致盲眼病。我们的研究报告称,AβOs 可诱导 RPE 变性,这是地理萎缩(GA)的一个临床特征,GA 是 AMD 的晚期威胁视力阶段,目前尚无有效治疗方法。我们证明 AβOs 可在体内诱导小鼠 RPE 中 NLRP3 炎性小体的激活,而嘌呤能 ATP 受体 P2RX7(NLRP3 炎性小体激活的上游介质)在 RPE 中的表达对于 AβO 诱导的 RPE 变性是必需的。两类小分子炎性小体抑制剂——核苷逆转录酶抑制剂(NRTIs)及其无抗逆转录病毒活性的改良类似物 Kamuvudines——均可抑制 AβOs 诱导的 RPE 变性。这些发现明确了 P2RX7 和 NLRP3 在 AMD 相关疾病模型中的重要性,并确定了炎性小体抑制剂可能是治疗 GA 的潜在方法。