摘要：SummaryExtended space travel is a goal of government space agencies and private companies. However, spaceflight poses risks to human health, and the effects on the nervous system have to be better characterized. Here, we exploited the unique experimental advantages of the nematodeCaenorhabditis elegansto explore how spaceflight affects adult neuronsin vivo. We found that animals that lived 5 days of adulthood on the International Space Station exhibited hyperbranching in PVD and touch receptor neurons. We also found that, in the presence of a neuronal proteotoxic stress, spaceflight promotes a remarkable accumulation of neuronal-derived waste in the surrounding tissues, suggesting an impaired transcellular degradation of debris released from neurons. Our data reveal that spaceflight can significantly affect adult neuronal morphology and clearance of neuronal trash, highlighting the need to carefully assess the risks of long-duration spaceflight on the nervous system and to develop adequate countermeasures for safe space exploration.Graphical AbstractDisplay OmittedHighlights•Spaceflight induces morphological remodeling of adult neurons inC. elegans•Hyperbranching is a common response of adult neurons to spaceflight•Neuronal debris accumulates in the hypodermis of proteo-stressed space-flown animalsNeuroscience; developmental neuroscience; space sciences
