Simulated microgravity induced damage in human retinal pigmentepithelial cells

[摘要] Purpose: The goal of this study was to determine the potentialdamage to the human retina that may occur from weightlessness duringspace flight using simulated microgravity.Methods: Human retinal pigment epithelial (hRPE) cells were culturedfor 24 h in a National Aeronautics and Space Administration-designedrotating wall bioreactor vessel to mimic the microgravity environment ofspace. Single-stranded breaks in hRPE DNA induced by simulated gravitywere measured using the comet assay. In addition, the production of theinflammatory mediator prostaglandin E2 (PGE2) was measuredin these cells 48 h after recovery from simulated microgravityexposure.Results: Simulated microgravity induced single-stranded breaks inthe hRPE DNA that were not repaired within 48 h. Furthermore, PGE2 production was dramatically increased 48 h after the initialmicrogravity-induced damage, indicating the induction of an inflammatoryresponse. There was less DNA damage and no PGE2 release in hRPEcells pretreated with the antiinflammatory agent cysteine during theirexposure to microgravity.Conclusions: We have demonstrated that the microgravity environmentgenerated by a NASA-designed rotating wall bioreactor vessel induces aninflammatory response in hRPE cells. This system thus constitutes a newmodel system for the study of inflammation in the retina, a system thatdoes not involve the introduction of an exogenous chemical agent orsupplementary irradiation. This in vitro method may also be useful fortesting novel therapeutic approaches for suppression of retinalinflammation. Furthermore, we suggest a safe prophylactic treatment forprevention of acute, transitory, or enhanced age-related permanentblindness in astronauts or flight personnel engaged in long-haulflights.

[学科分类] 生物化学/生物物理