The Preferred Apoptotis Pathways in Humans Differ in Case of Prolonged Contact with Low Dose Alpha and Gamma Ionizing Radiation

Purpose: To establish the preferred signal pathways by which apoptosis is initiated in human’s cells, when the most intense initial signal is low dose dense ionizing α-radiation or rarely ionizing γ-radiation, there was performed the measurement and subsequent analytical evaluation of the expression levels for 7 key marker genes: jnk, bad, tp53, casp-8, casp-9 as apoptosis inductors, and bcl-2, akt as apoptosis inhibitors. Material and methods: Two cohorts of personnel from one of the atomic energy use organizations (AEUO), exposed to a prolonged combined low dose (α+γ)-irradiation, were examined. The cohorts differed in α-radiation contribution to the accumulated radiation exposure: γ-radiation prevailed in one cohort, while α-radiation – in another. Using the device MagPix and a multiplex immuno-cytochemical biomarkers’ analysis methodology, the preferred signal pathways of apoptosis induction, as well as their intensity, were revealed for each cohort. Results: Comparison of all involved genes’ expression showed essential differences in the main “cast of players” that initiate apoptosis in α- and γ-irradiated cohorts. The survey resulted in the complied map of the preferred apoptosis pathways in each cohort. Molecular mechanisms were identified that predispose to greater oncotension in the a-irradiated cohort compared to the γ-irradiated cohort. Conclusion: The survey results are important for developing the set of factors that should be taken into account in personalized stuff selection for work in radiation hazardous environments. This area is developed by the Radiation and Radiation-Monitoring Register of Occupational Nuclear Personnel (RFNC-VNIIEF, Sarov) within the framework of creating the automated system for assessing and predicting the human body’s individual response to different ionizing radiation types. The automated system will be used for the benefit of the nuclear and other strategic science and industry branches, as well as for the benefit of radiation medicine.