Protection against prenatal irradiation-induced genomic instability and its consequences in adult mice by Ocimum flavonoids, orientin and vicenin.

To study the protective effect of orientin and vicenin against early genomic effects of foetal irradiation and their late consequences in mice. Fourteen-day pregnant mice were exposed to 1 Gy 60Co gamma-radiation 30 min after an intraperitoneal injection of orientin or vicenin (50 microg kg(-1) body weight). Chromosomal aberrations were studied in foetal liver cells and their spleen colonies (three passages, colony-forming units-spleen CFU-S1, CFU-S2, CFU-S3) and 1-12 months post-partum bone marrow. Peripheral blood counts and solid tumours were recorded to 12 and 20 months, respectively. Irradiation significantly increased the percent aberrant cells and aberrations/cell in foetal liver and CFU-S1. These effects decreased in later passages of CFU-S and were not seen at 1-6 months post-partum, but increased significantly from 9 months. Total blood counts showed significant reduction from 6 months, while neutrophils increased from 3 months post-partum. Solid tumour incidence in adults increased significantly, with a decrease in age at detection. Orientin/vicenin significantly reduced the chromosomal anomalies in foetal and adult haemopoietic cells, restored blood counts to the normal range, and significantly reduced tumour incidence and delayed tumour development to control age. Orientin and vicenin protect against foetal irradiation-induced genomic damage and instability, thereby reducing the delayed chromosomal abnormalities and tumorigenesis in adult.