Dataset Information

Effects of PCB 52 Exposure Via Sub-Acute Nose-Only Inhalation on Gene Expression in Livers of Adolescent Rats

ABSTRACT: Polychlorinated biphenyls (PCBs) are persistent environmental toxicants that pose a variety of health risks in humans. PCB 52 has been found in the indoor air of schools where adolescent students and staff are being actively exposed. This study examined the livers of adolescent Sprague-Dawley rats after sub-acute exposure to PCB 52 via nose-only inhalation. Rats were exposed for 4 hours daily for 28 consecutive days. RNA extracted from both male and female livers were submitted for RNA sequencing to compare the effects of PCB 52 on the expression of genes in the liver.

ORGANISM(S): Rattus norvegicus

PROVIDER: GSE255048 | GEO | 2024/02/27

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:(Abstract) Toxicogenomics has great potential for enhancing our understanding of environmental chemical toxicity, hopefully leading to better-informed human health risk assessments. This study employed toxicogenomic technology to reveal species differences in response to two prototypical aryl hydrocarbon receptor (AHR) agonists, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and the polychlorinated biphenyl (PCB) congener PCB 126. Dose responses of primary cultures of rat and human hepatocytes were determined using species-specific microarrays sharing over 4,000 gene orthologs. Forty-seven human and 79 rat genes satisfied dose response criteria for both chemicals and were subjected to further analysis including the calculation of EC50 and the relative potency (REP) of PCB 126 for each gene. Only 5 responsive orthologous genes were shared between the two species, yet the geometric mean of the REPs for all rat and human modeled responsive genes were 0.06 (95% Confidence Interval (CI); 0.03-0.1) and 0.002 (95% CI; 0.001-0.005), respectively, suggesting broad species differences in the initial events that follow AHR activation but precede toxicity. This indicates that there are species differences in both the specific genes that responded and the agonist potency and relative potency for those genes. This observed insensitivity of human cells to PCB 126 is consistent with more traditional measurements of AHR activation (i.e., CYP1A1 enzyme activity) and suggests that the species difference in PCB 126 sensitivity is likely due to certain aspects of AHR function. That a species divergence also exists in this expanded AHR-regulated gene repertoire is a novel finding and should help when extrapolating animal data to humans. Experiment Overall Design: Primary hepatocyte cultures, separated into 2 pools of 3 female Sprague Dawley rats each, were treated with vehicle (0.5% DMSO), TCDD (-14 to -6.5 log10 M) , or PCB 126 (-12 to -5 log10 M) for 48h. Total RNA was extracted and screened with RG-U34A microarrays for dose response.

Dataset Information

Effects of PCB 52 Exposure Via Sub-Acute Nose-Only Inhalation on Gene Expression in Livers of Adolescent Rats

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure