Adriamycin Induced Genetic Toxicity as Demonstrated by the Allium Test

Abstract

The present investigation was carried out to study the cytological effects of adriamycin on root tip cells of Allium cepa. The roots of selected onion bulbs were placed in 3 different concentrations 0.1%, 1% and 10% of adriamycin solution for different durations, ranging from 3 hours to 24 hours. The treatments were so timed as to study the effects of the drug at specific stages in the mitotic cycle.
The most important effect of the drug was the drastic lowering of the mitotic index. Interphasic cell death, nuclear lesions, nuclear dissolution, nuclear polymorphism and somatic reduction of chromosomes were also observed. Important abnormalities encountered at metaphase were C-metaphase, clumping, abnormal equatorial plate and delayed metakinesis. Chromatid bridges, sticky bridges, chromosome fragments, unequal distribution of chromosomes with paired chromatids, acute fragmentation leading to chromatin globules etc. were frequent in treated cells. Failure of cytokinesis resulting in multinucleate cells was also noticed.
The present results suggest that adriamycin inhibits not only DNA synthesis but also protein synthesis, either directly or indirectly by its binding with DNA resulting in the prevention of its unwinding for transcription of spindle protein messengers. To arrest cell division, the best time of application appears to be the G₁, just before the onset of DNA synthesis.