Aging is a major risk factor for many neurodegenerative diseases. Klotho (KL) is a glycosylated transmembrane protein that is expressed in the choroid plexus and neurons of the brain. KL exerts potent anti-aging effects on multiple cell types in the body but its role in human brain cells remains largely unclear. Here we show that human cortical neurons, derived from human pluripotent stem cells in 2D cultures or in cortical organoids, develop the typical hallmarks of senescent cells when maintained in vitro for prolonged periods of time, and that moderate upregulation or repression of endogenous KL expression in cortical organoids inhibits and accelerates senescence, respectively. We further demonstrate that KL expression alters the expression of senescence-associated genes including, extracellular matrix genes, and proteoglycans, and can act in a paracrine fashion to inhibit neuronal senescence. In summary, our results establish an important role for KL in the regulation of human neuronal senescence and offer new mechanistic insight into its role in human brain aging.

衰老是许多神经退行性疾病的主要危险因素。Klotho (KL) 是一种糖基化的跨膜蛋白，在脑的脉络丛和神经元中表达。KL 对体内多种细胞类型具有强大的抗衰老作用，但其在人脑细胞中的作用仍不清楚。在这里，我们表明源自二维培养物或皮质类器官中的人类多能干细胞的人类皮质神经元在体外长时间维持时会形成衰老细胞的典型特征，并且会适度上调或抑制内源性KL表达皮质类器官分别抑制和加速衰老。我们进一步证明KL表达改变衰老相关基因的表达，包括细胞外基质基因和蛋白多糖，并且可以旁分泌方式抑制神经元衰老。总之，我们的结果确立了 KL 在调节人类神经元衰老中的重要作用，并为其在人类大脑衰老中的作用提供了新的机制见解。