Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago, Chile.
Geroscience Center for Brain Health and Metabolism (GERO), Santiago, Chile.
Aging Cell. 2023 May;22(5):e13814. doi: 10.1111/acel.13814. Epub 2023 Mar 27.
Age is the main risk factor for the development of neurodegenerative diseases. In the aged brain, axonal degeneration is an early pathological event, preceding neuronal dysfunction, and cognitive disabilities in humans, primates, rodents, and invertebrates. Necroptosis mediates degeneration of injured axons, but whether necroptosis triggers neurodegeneration and cognitive impairment along aging is unknown. Here, we show that the loss of the necroptotic effector Mlkl was sufficient to delay age-associated axonal degeneration and neuroinflammation, protecting against decreased synaptic transmission and memory decline in aged mice. Moreover, short-term pharmacologic inhibition of necroptosis targeting RIPK3 in aged mice, reverted structural and functional hippocampal impairment, both at the electrophysiological and behavioral level. Finally, a quantitative proteomic analysis revealed that necroptosis inhibition leads to an overall improvement of the aged hippocampal proteome, including a subclass of molecular biofunctions associated with brain rejuvenation, such as long-term potentiation and synaptic plasticity. Our results demonstrate that necroptosis contributes to age-dependent brain degeneration, disturbing hippocampal neuronal connectivity, and cognitive function. Therefore, necroptosis inhibition constitutes a potential geroprotective strategy to treat age-related disabilities associated with memory impairment and cognitive decline.
年龄是神经退行性疾病发展的主要危险因素。在衰老的大脑中,轴突变性是人类、灵长类动物、啮齿动物和无脊椎动物中神经元功能障碍和认知障碍之前的早期病理事件。坏死性凋亡介导损伤轴突的变性,但坏死性凋亡是否会随着年龄的增长引发神经退行性变和认知障碍尚不清楚。在这里,我们表明,坏死性凋亡效应分子 Mlkl 的缺失足以延迟与年龄相关的轴突变性和神经炎症,防止老年小鼠的突触传递减少和记忆下降。此外,在老年小鼠中,短期靶向 RIPK3 的坏死性凋亡药理学抑制可恢复海马体的结构和功能损伤,无论是在电生理还是行为水平上。最后,定量蛋白质组学分析表明,坏死性凋亡抑制会导致衰老海马体蛋白质组的整体改善,包括与大脑年轻化相关的一类分子生物功能,如长时程增强和突触可塑性。我们的研究结果表明,坏死性凋亡会导致与年龄相关的大脑退化,扰乱海马体神经元的连接和认知功能。因此,坏死性凋亡抑制可能成为一种潜在的治疗与记忆障碍和认知能力下降相关的与年龄相关的功能障碍的保护策略。