2R,3R-trans-Dihydroquercetin Has Powerful Antioxidant Properties, Prevents DNA and Protein Damage, and Protects Mice from Injury Caused by Radiation-Induced Oxidative Stress

(1) Background: The search for new polymodal antioxidants to correct oxidative stress of various origins and its consequences remains one of the most pressing and rapidly developing areas of biomedical research. (2) Methods: Hydrogen peroxide and hydroxyl radical detection, induced luminescence assay, ELISA for 8-oxoguanine detection, animal survival, blood cell count, micronucleus test, and PCR were used. (3) Results: 2R,3R-trans-dihydroquercetin (DHQ) was shown to reduce the amount of hydrogen peroxide and hydroxyl radicals formed during water radiolysis, leading to reduced damage to biomolecules. DHQ is a radioprotector, most effective at a dose of 300 mg/kg administered 15 min before radiation exposure. The dose reduction factor is 1.22. DHQ administration reduces the severity of radiation-induced leukopenia and thrombopenia by protecting red bone marrow cells. The mechanism of DHQ’s radioprotective action is fundamentally different from that of classical stress response inducers and is based on the normalization of the target cell transcriptional profile, rather than its hyperstimulation. (4) Conclusions: DHQ’s ability to restore the expression of antioxidant defense, DNA repair, and apoptotic genes to physiological levels under radiation exposure allows it to be considered a promising pharmacological agent for the correction of radiation-induced damage to normal tissues.