Radioprotective Properties of the Phytochemically Characterized Extracts of Crataegus monogyna, Cornus mas and Gentianella austriaca on Human Lymphocytes in vitro

Abstract
The objective of the present study is to evaluate the radioprotective properties of extracts of Crataegus monogyna Jacq. (Rosaceae) fruit, Cornus mas L. (Cornaceae) leaves and Gentianella austriaca (A. Kern. & Jos. Kern.) Holub (Gentianaceae) aerial parts on cultured human peripheral blood lymphocytes in vitro after irradiation with 2 Gy of 60Co γ-rays. Plants were collected at Mt. Maljen in Serbia, air-dried and powdered, and the total phenolic content was analyzed. In C. mas leaves, ellagic and gallic acid were found to be the dominant compounds, whereas C. monogyna fruit was rich in procyanidins and flavonoids. The main constituents of G. austriaca aerial parts were γ-pyrones and secoiridoids. Cell cultures were treated with four different doses of plant extracts (0.1 mg/mL to 0.4 mg/mL). Treatment with the lowest dose gave the best protective effect. Significant radiorecovery potentials of C. mas and C. monogyna were observed, seen as a reduced incidence of radiation-induced micronuclei (19.23 % and 13.24 %, respectively), reduced levels of lipid peroxidation products (50.04 % and 13.18 %, respectively) and two-fold enhanced apoptosis. Both extracts slowed down cell proliferation gradually, enabling more time for repair. G. austriaca possesses strong antioxidant properties, significantly reducing lipid peroxidation and the incidence of micronuclei (for 30.88 % and 35.56 %, respectively) while enhancing apoptosis with no perturbation of the cell cycle. This study may contribute to the search for novel radioprotective agents.