Antigenotoxic and Antimutagenic Potentials of Proline in Allium cepa Exposed to the Toxicity of Cadmium

Abstract

This study was conducted to evaluate whether the application of proline as a potential osmoprotectant at different doses could improve the genotoxic and mutagenic effects caused by plant exposure to cadmium salts. For this purpose, the Comet assay was used, which allows the rapid detection of DNA damage shortly after its occurrence, before the DNA is repaired, as well as the discrimination of the DNA damage limited to specific cells in a heterogeneous population. After treatment of Allium cepa roots with 75µM CdSO4·H2O (Cd sample), a DNA percentage of 35.24% was recorded in the tail. In the samples treated first with proline and then with cadmium (pre-treatment group), the percentage DNA in the tail was reduced by 24.8% compared with the Cd sample. Instead, in the post-treatment group (samples treated first with cadmium and then with proline), the percentage DNA in the tail was reduced by 69.04% compared with the Cd sample. All cadmium treatments induced chromosomal aberrations (CAs). Compared with the CAs values obtained after Cd treatment, the reduction was 75.6% in the pre-treatment group and 55.39% in the post-treatment group. The results of this study highlighted that exogenous application of proline alleviated the genotoxic effect of cadmium.