The rise in aging population worldwide is increasing death from cancer, including glioblastoma. Here, we explore the impact of brain aging on glioma tumorigenesis. We find that glioblastoma in older patients and older mice displayed reduced neuronal signaling, including a decline of NTRK-like family member 6 (SLITRK6), a receptor for neurotrophic factor BDNF. This reduction was linked to the systemic decline of nicotinamide adenine dinucleotide (NAD+) with aging, as old mice exposed to young blood via parabiosis or supplemented with the NAD+ precursor NMN (nicotinamide mononucleotide) reverted phenotypically to young-brain responses to glioma, with reactivated neuronal signaling and reduced death from tumor burden. Interestingly, the phenotypic reversal by NMN was largely absent in old mice undergoing parabiosis with BDNF+/- young mice and in BDNF+/- mice undergoing tumor challenge, supporting the notion that the lower NAD+-BDNF signaling in the aging brain aggravated glioma tumorigenesis. We propose that the aging-associated decline in brain NAD+ worsens glioma outcomes at least in part by decreasing neuronal/synaptic activity and increasing neuroinflammation.

中文翻译：

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NAD + / BDNF介导的神经元激活可逆转脑衰老相关的神经胶质瘤性状

世界范围内老龄化人口的增加正在增加包括胶质母细胞瘤在内的癌症死亡人数。在这里，我们探索脑老化对神经胶质瘤肿瘤发生的影响。我们发现，成年胶质母细胞瘤在老年患者和老年小鼠中表现出减少的神经元信号传导，包括神经营养因子BDNF受体NTRK样家族成员6（SLITRK6）下降。这种减少与烟酰胺腺嘌呤二核苷酸（NAD +）随着衰老而全身性下降有关，因为通过共生体暴露于年轻血液中或补充了NAD +前体NMN（烟酰胺单核苷酸）的年老小鼠在表型上恢复为对胶质瘤的年轻大脑反应，并被重新激活神经元信号传递和减少因肿瘤负担而导致的死亡。有趣的是 NMN的表型逆转在与BDNF +/-年轻小鼠共生的老年小鼠和经历肿瘤攻击的BDNF +/-小鼠中基本不存在，这支持了在衰老的脑中较低的NAD + -BDNF信号转导加剧了神经胶质瘤肿瘤发生的观点。我们提出与大脑衰老相关的NAD +下降至少部分地通过减少神经元/突触活动和增加神经炎症而使神经胶质瘤恶化。