Asbestos Increases Mammalian AP- Endonuclease Gene Expression, Protein Article

Asbestos Increases Mammalian AP- Endonuclease Gene Expression, Protein Levels, and Enzyme Activity in Mesothelial Cells - Article Example Most previous studies have focused on DNA repair in bacteria. Asbestos has been found to increase the production of 8-hydroxydeoxyguanosine (8OHdG), a modified DNA nucleoside. Conversion to 8OHdG has been attributed to oxidative stress. Inheritance of damaged DNA can result in permanent mutation, leading to disease, and cell proliferation. 8OHdG can be removed by DNA base excision repair enzyme systems in mammals and through the action of AP endonuclease (APE), which acts similarly to E. coli exonuclease III and endonuclease IV. AP endonuclease excises the modified base on a segment of the DNA strand. The lacking base is then replaced through the action of other members of the DNA repair system, restoring the original, correct sequence of the DNA. This paper was also the first to show that a carcinogen that is associated with oxidant stress in normal lung cells induces AP endonuclease. The results obtained from the research can be used in designing new studies that will lead to a higher understanding of the role of AP endonuclease in DNA damage repair and its subsequent effects like cancer and diseases that are due to DNA mutations. The main objective of the study was to evaluate and understand how asbestos-induced DNA repair is carried out. The experiment was performed by exposing rat mesothelial pleural cells, which form the membrane surrounding the lungs, to non-toxic levels of crocidolite asbestos, a potent agent of mesothelioma in humans. After 24 to 72 hours exposure to asbestos, cells were removed from the medium. Cell viability was determined, and nuclear and mitochondrial extracts were prepared to determine APE protein levels, mRNA concentrations, and enzyme activity. Immunologic techniques (Western and Northern blot analyses) and imaging (confocal laser microscopy) were used to measure levels of the different analytes. Techniques were described in detail, which makes it easy for other researchers to