Restier-Verlet J, Ferlazzo ML, Granzotto A, Al-Choboq J, Bellemou C, Estavoyer M, Lecomte F, Bourguignon M, Pujo-Menjouet L, Foray N. Accelerated Aging Effects Observed In Vitro after an Exposure to Gamma-Rays Delivered at Very Low and Continuous Dose-Rate Equivalent to 1-5 Weeks in International Space Station. Cells. 2024
Space exploration and human habitation outside of the earth’s atmosphere continues to challenge scientists because of the physiologic restraints of humans. Radiation exposure on Mars or interplanetary transit may place humans at risk for genomic mutations. According to this study, space radiation arises from a “bath of high energy rays (0.1-0.5 mGy per mission day.” This type of radiation penetrates skin and may impact deeper tissue such as the heart and bones.
The closest simulation to the effects of radiation are found at the MarsSimulator facility in France and this source comes from a bag of thorium salts which elicits exposure of 120 mSv/y - similar to the exposure found on the ISS. Using this model, the scientists assessed DNA double strand breasks induced by 1-5 weeks of exposure in ISS conditions.
Results demonstrated, in-vitro, For the lens, bones, and radiosensitive skin cells tested, perinuclear localization of phosphorylated forms of ataxia telangiectasia mutated protein (pATM) was observed during the 1st to 3rd week of exposure;” which suggests that low dose rate of 120 mSv/y may accelerate the aging process in these tested tissues.
In clinical practice, we know that UV sun exposure and solar radiation penetrating through our atmosphere is harmful effects on human genes and physiology. The exponential increase in radiation doses for space travel, supra-atmospheric orbit, or interplanetary human manned space missions is an incredible challenge for non-automated travel. Limitations on many of these studies include the fact that many of the manifestations of radiation occur years later, and the animal and in-vivo studies may not adequately predict human behaviors over a lifetime.
Raffy Karamanoukian MD FACS
Los Angeles
Kare Plastic Surgery Journal Club
www.karesurgery.com