A compound found in cruciferous vegetables such as cabbage, broccoli, and cauliflower may be the key to radiation protection, scientists have found.
The compound, called 3’3-diindolymethane or DIM, is under investigation as a cancer preventative agent. Used as a potential medical countermeasure, DIM may be able to prevent or mitigate acute radiation syndrome due to whole body exposure. Previously studied as a cancer prevention agent, this is the first instance in which DIM has been considered as a radiation protector.
One of the study’s author Dr. Eliot Rosen of Georgetown Lombardi Comprehensive Cancer Center in the US describes why this new development holds great intrigue and significance: “I find it fascinating that a known cancer preventive agent (DIM) has powerful radiation protection properties and wonder if there is a relationship in the case of DIM between its radioprotection and cancer prevention mechanisms.”
The early stage laboratory study administered DIM to rodents in a multidose schedule in order to identify whether DIM could protect against the effects of exposure to radiation.
Results from the experiment demonstrated that the compound protected the animals against lethal doses of body irradiation up to 13 Gy. This was the case whether DIM dosing was initiated before or up to 24 hours after radiation exposure. The irradiated rodents injected with DIM survived longer than those left untreated.
This suggests that DIM may be useful in protecting against the effects of radiation. Rosen commented “DIM could potentially be used to protect normal (non-tumor) tissues against radiation therapy treatments for cancer.”
The compound functions uniquely from other radioprotectors and mitigators. “DIM works in part by amplifying the normal DNA damage response that occurs when cells and tissues are irradiated. DIM also acts to prevent radiation-caused apoptosis, a type of programmed cell death. The first mechanism is novel among radiation protectors, though other protectants might also act to block apoptosis.”
The experimental evidence collected thus far supports DIM as a potential radioprotector and mitigator. In terms of the direction of future research, Rosen added: “We will work toward FDA approval of DIM as a radioprotectant and mitigator. This is a complex process that will involve determining the best way to deliver DIM (e.g. oral, subcutaneous, intramuscular) and other animal testing studies.”
It is uncertain whether an outcome similar to the irradiated rodents treated with DIM is possible in humans. However if so, the potential applications for DIM may venture into orbit as a radioprotector for astronauts exposed to the harsh environment of space.
“Although speculative at this time, DIM could be used to protect against radiation received by astronauts during space travel (eg., cosmic radiation). One has to be careful because there are different types of radiation, and we don’t yet know whether DIM protects against all forms of radiation.”
With the duration of time that astronauts spend in space set to increase with future Mars and asteroid missions, DIM may provide a method of radiation protection that is sustainable and that can be grown in-situ due to its vegetable origins.
The findings are published in the journal Proceedings of the National Academy of Sciences.
Image credits: Charles Smith