Research Article

Expression profiles of DNA repair-related genes in rat target organs under subchronic cadmium exposure

Published: January 26, 2015
Genet. Mol. Res. 14 (1) : 515-524 DOI: 10.4238/2015.January.26.5

Abstract

We aimed to evaluate the toxicity of long-term exposure to different cadmium (Cd) doses in rats and expression profiles of DNA repair-related genes. The model rats were exposed to different concentrations of CdCl2 for 3 months, and 5 DNA repair-related genes - hMSH2, MLH1, XRCC1, hOGG1, ERCC1 - were cloned in different tissues, including the liver, kidney, heart, and lung. Accumulated amounts of Cd were detected in the tissues. Gene and protein detections were conducted via fluorescence quantitative real-time polymerase chain reaction and Western blotting, respectively. Methylated sequences of the 5 DNA repair-related gene promoters were used to investigate whether the low expression levels of the genes were related to methylation of the promoter. In the Cd-exposed group, 3 DNA repair genes (i.e., XRCC1, hOGG1, and ERCC1) significantly decreased in the rat liver, kidney, heart, and lung according to the β-actin internal standard (P hOGG1 gene expression decreased by 75% in the kidney, and XRCC1 gene expression decreased by 5% in the liver and heart when compared to the control group (P ERCC1, XRCC1, and hOGG1) played an important role in the rat response to Cd exposure but not DNA methylated protection.

We aimed to evaluate the toxicity of long-term exposure to different cadmium (Cd) doses in rats and expression profiles of DNA repair-related genes. The model rats were exposed to different concentrations of CdCl2 for 3 months, and 5 DNA repair-related genes - hMSH2, MLH1, XRCC1, hOGG1, ERCC1 - were cloned in different tissues, including the liver, kidney, heart, and lung. Accumulated amounts of Cd were detected in the tissues. Gene and protein detections were conducted via fluorescence quantitative real-time polymerase chain reaction and Western blotting, respectively. Methylated sequences of the 5 DNA repair-related gene promoters were used to investigate whether the low expression levels of the genes were related to methylation of the promoter. In the Cd-exposed group, 3 DNA repair genes (i.e., XRCC1, hOGG1, and ERCC1) significantly decreased in the rat liver, kidney, heart, and lung according to the β-actin internal standard (P hOGG1 gene expression decreased by 75% in the kidney, and XRCC1 gene expression decreased by 5% in the liver and heart when compared to the control group (P ERCC1, XRCC1, and hOGG1) played an important role in the rat response to Cd exposure but not DNA methylated protection.