Texas Southern University
Pavani Gonnabathula is a Ph.D. Candidate and Teaching assistant at Texas Southern University from Dept. Of Environmental and Interdisciplinary Sciences, Houston, Texas. She originated from Southern part of India, received her Master’s in Industrial Pharmacy from Kakatiya University, India and Bachelors in Pharmacy from Andhra University, India. She served as a Lecturer in Pharmacy for two years from 2010 to 2012 at Govt. Polytechnic for Women, Srikakulam, India. Based on her academic and research profile she decided to join interdisciplinary Ph.D. program which she felt as an extension of her research career. Her research interests include toxicokinetic studies of emerging contaminants, finding of cellular & molecular dysregulations caused by these contaminants, gene regulation etc.
Effects of Emerging Contaminants at Trace Level on Nitric Oxide (NO) Levels and Superoxide Dismutase (SOD) Activity in Mice: Role of Sex and PPARα
Toxicological effects of traditional water contaminants such as lead and arsenic are well known. Recently, trace amounts of emerging contaminants such as pharmaceuticals, personal care products, pesticides, herbicides and endocrine disrupting compounds are detected in our drinking water. These trace chemical pollutants pose environmental and human health concerns. So, we have investigated the effects of trace concentrations of multiple pesticides (MP) on the regulation of NO signaling molecule levels and SOD activity in the tissues from wild type and PPARα knockout mice. Wild type/ PPARα knockout mice (male and female) were exposed to trace concentrations of multiple pesticides comprising atrazine, dieldrin, endrin, endosulfan and anthracene (1-100ng/L) in drinking water for six weeks. Blood and organs were collected, homogenized and NO levels and SOD activity were determined by Griess/SOD assays. In the blood samples, treatment with low MP reduced NO (20%) in the female with no change in the male. NO level was 90% higher in wild type compared to PPARα knockout female. NO levels increased in tissues from wild type: spleen (80%), heart (75%), liver (80%), kidney (85%) and brain (85%), while in knockout NO levels was reduced in spleen (45%) but increased in the kidney (55%) with no change in the brain, liver, and heart. In the male, NO levels were reduced in the heart (66%) and liver (40%) with no change in the kidney, spleen, brain, and testicles. Blood SOD activity is 90% greater in male than female; MP attenuated SOD activity by 20% with no change in the female. Female tissue SOD activity was significantly reduced in the heart (30%), liver (25%) and spleen (25%) of treated mice with no effect in the brain and the kidney. In the PPARα knockout mice, SOD activity was significantly increased in the heart (50%) and liver (25%) but not in the kidney, spleen, and brain. Thus, low concentrations of multiple pesticides caused selective dysregulation of NO/SOD systems in different organs of the body. The effects observed was sex dependent and may be influenced by genetic status as in PPARα knockout. These results present a scenario that implicates nano-concentrations of series of organic contaminants that can cause cellular and molecular dysregulations of bio molecules 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 and is of interest.