| The health risk of spaceflight-induced neuronal damage and potential adverse neurovascular effects has long been a concern. A recent report shows that more than 50% of the astronauts returning from space were diagnosed with visual problems that can cause blurry vision. Our previous studies from mice that had been subjected to spaceflights (space shuttle mission Space Transportation System (STS)-118 and STS-135) showed that environmental conditions during space travel lead to oxidative stress and induce adverse microvessel remodeling in the retina. To date, the mechanisms behind these effects are not fully understood.
The objective of this proposed project is to characterize the effect of Bion-M2 mission on retinal vascular remodeling and visual function. Furthermore, the molecular and cellular mechanisms involving oxidative stress-induced vascular response and impaired blood-retina-barrier (BRB) and blood-brain barrier (BBB) integrity will be investigated.
Mature male and female mice will be exposed to spaceflight environment on board Bion-M2 mission for 30 days and compared to that of ground-based control groups. Animals will be sacrificed 3-15 days after return to Earth. Non-invasive intraocular pressure (IOP) and electroretinography (ERG) will be used to measure intraocular pressure and retinal function before sacrifice. Eyes and brains will be removed for fixed or frozen for ex vivo diffusion tensor imaging (DTI) imaging, genomic profiling, and immunohistological analysis.
Together, our unique, integrative, quantitative approaches with advanced imaging techniques and comprehensive genomic analysis will provide insight into the cellular mechanism of spaceflight-induced effects on the interaction of parenchymal activity with neurovascular response and provide criteria for risks of functional detriments. Understanding how spaceflight impacts neurovascular remodeling and BRB/BBB function will help focus the approach for more effective countermeasures during human spaceflight and planetary exploration.