Addressing Spaceflight Biology through the Lens of a Histologist-Embryologist

Embryogenesis and fetal development are highly delicate and error-prone processes in their core physiology, let alone if stress-associated factors and conditions are involved. Space radiation and altered gravity are factors that could radically affect fertility and pregnancy and compromise a physiological organogenesis. Unfortunately, there is a dearth of information examining the effects of cosmic exposures on reproductive and proliferating outcomes with regard to mammalian embryonic development. However, explicit attention has been given to investigations exploring discrete structures and neural networks such as the vestibular system, an entity that is viewed as the sixth sense and organically controls gravity beginning with the prenatal period. The role of the gut microbiome, a newly acknowledged field of research in the space community, is also being challenged to be added in forthcoming experimental protocols. This review discusses the data that have surfaced from simulations or actual space expeditions and addresses developmental adaptations at the histological level induced by an extraterrestrial milieu.

Automated summary

Embryogenesis and fetal development are vulnerable to stress-associated factors such as space radiation and altered gravity, which can compromise normal physiological organogenesis. However, the effects of cosmic exposures on mammalian embryonic development are poorly understood. This review explores the impact of extraterrestrial conditions on histological level developmental adaptations observed in space simulations or actual expeditions, including the role of the vestibular system and the potential influence of the gut microbiome.