Emerging contaminants at trace levels of pesticides perturbs biomolecules in different organs in mice: Role of peroxisome proliferator-activated receptor-alpha

Abstract

Information is lacking on the consequences of chronic exposure to emerging contaminants at environmentally relevant (trace concentrations) on biomolecules. Environmental exposure to these chemical mixtures happens at trace concentrations and at multiple molecular interactions. The consequences of trace concentrations of multiple pesticides (MPs) on the regulation of selected biomolecules nitric oxide (NO), thiols, superoxide dismutase (SOD), and glutathione S-transferase (GST) in the tissues from wild type (WT) and genetically deficient- peroxisome proliferator-activated receptor-alpha (PPARα) knockout (Null) mice were investigated. Mice were exposed to trace concentrations of MPs: Atrazine, dieldrin, endrin, endosulfan, and anthracene (1–100 ng/L) in drinking water for 6 weeks. Organs were collected and homogenized; NO, protein and non-protein thiol levels, as well as SOD and GST activities were determined. Differential and organ selective effects of the treatments were observed in the WT and PPARα knockout. Increased NO levels were observed in the organs from WT with limited increase in the kidney (Null). SOD activity was decreased in the organs from the WT and was increased in the PPARα knockout when compared to the control. Thiol level was significantly increased in the heart and spleen in the WT and in the heart of the PPARα knockout mice when compared to the control. Non-protein thiol concentration was reduced in the heart and kidney (WT) and reduced in the liver of the PPARα knockout when compared to the control. GST activity was significantly decreased in the liver and spleen (WT) and was significantly elevated in all organs in the PPARα knockout mice when compared to the WT. The low concentrations of MPs may have caused selective dysregulation of biomolecules in different organs of the body. These effects observed may be influenced by genetic status such as in PPARα deficiency. These results present a scenario that implicates nanoconcentrations of series of organic contaminants that can cause cellular and molecular dysregulations of biomolecules precipitating toxicity and pathology that can be a threat to human health. Further, investigation into the molecular mechanism(s) and signaling pathway(s) implicated in these dysregulations is warranted.