Sodium chlorate induces DNA damage and DNA-protein cross-linking in rat intestine: A dose dependent study.
Sodium chlorate (NaClO3) is widely used in paper and pulp industries and as a non-selective herbicide. It is also a major by-product generated upon disinfection of drinking water by chlorine dioxide. In this study, we have investigated the genotoxicity of NaClO3on the small intestine of rats. Adult male rats were divided into 5 groups: one control and four NaClO3treated groups. The NaClO3treated groups were given a single acute oral dose of NaClO3(100, 250, 500 and 750 mg/kg body weight) and sacrificed 24 h later. Administration of NaClO3caused significant DNA damage in a dose dependent manner in the rat intestine. This was evident from the comet assay which showed DNA strand breaks and was further confirmed by agarose gel electrophoresis and release of free nucleotides. Increased DNA protein cross-linking in NaClO3administered groups showed formation of a critical lesion which hampers activities of proteins/enzymes involved in DNA repair, transcription and replication. Thus, oral administration of NaClO3induces DNA damage in the rat intestine, probably through chlorate induced production of reactive oxygen species.
Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India.
Shaikh Nisar
SN
Ali
Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India.
Fariheen Aisha
FA
Ansari
Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India.
Hussain
H
Arif
Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India. Electronic address: riazmahmood2002@yahoo.co.in.
Riaz
R
Mahmood
D000284:Administration, Oral; D000818:Animals; D001835:Body Weight; D002704:Chlorates / Q000008:administration & dosage / Q000633:toxicity*; D017606:Chlorine Compounds; D020552:Comet Assay; D003432:Cross-Linking Reagents / Q000737:chemistry; D004247:DNA / Q000737:chemistry; D004249:DNA Damage; D004260:DNA Repair; D004203:Disinfection; D004305:Dose-Response Relationship, Drug; D060766:Drinking Water; D006540:Herbicides; D007421:Intestine, Small / Q000187:drug effects; D008297:Male; D010087:Oxides; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism
D002704:Chlorates; D017606:Chlorine Compounds; D003432:Cross-Linking Reagents; D060766:Drinking Water; D006540:Herbicides; D010087:Oxides; D017382:Reactive Oxygen Species; C025109:chlorine dioxide; D004247:DNA; C032706:sodium chlorate
Comet assay; DNA damage; DNA-protein cross-links; Genotoxicity; NaClO(3)