Hypothalamus controls the speed of ageing

Dongsheng Cai and colleagues previously showed that the hypothalamus has a critical role in systemic ageing. Here they observe a substantial loss of hypothalamic stem cells in middle-aged mice. They show in several mouse models that ablation of these cells results in ageing-like physiological changes and a shortened lifespan. Conversely, ageing could be slowed and lifespan extended by transplantation of healthy hypothalamic stem cells into middle aged mice. Hypothalamic stem cells secrete exosomal miRNAs, contributing to a pool of circulating miRNAs in the cerebrospinal fluid that declines with age. These secreted exosomes contribute, at least in part, to a deceleration of ageing. The authors conclude that the speed of ageing is partially controlled by hypothalamic stem cells and their exosomal miRNAs in the cerebrospinal fluid.