Radiotherapeutic Potential of the Extracts of Andrographis paniculata and Swertia chirayita

Ethanolic extracts of two controversial medicinal plants Andrographis paniculata (ApE) and Swertia chirayita (ScE) were evaluated for its potential to enhance the repair of radiation-induced DNA damage. Post-irradiation administration of these extracts to mice resulted in faster cellular DNA repair, as revealed from the increased Cellular Repair Index (CRI) of blood leukocytes. Exposure of mice to 2 Gy whole-body gamma radiation resulted in the formation of strand breaks of cellular DNA of bone marrow cells and the unrepaired strand breaks eventually lead to the formation of micronuclei in the reticulocytes. Administration of ApE and ScE under post-irradiation conditions showed a decrease in the number of micronucleated reticulocytes. Administration of these extracts also aided in the regeneration of the immune system as revealed from the induction of endogenous spleen colony formation in mice exposed to whole body gamma radiation. Thus, the studies revealed that ethanolic extracts of Andrographis paniculata and Swertia chirayita abetted the revival of immune system following radiation exposure and the induction of faster and legitimate DNA repair can be the underlying mechanism.