Project description:Transcriptomic and metabonomic methods were used to investigate mice’s responses to drinking source water (DSW) exposure. After mice were fed with DSW for 90 days, hepatic transcriptome was characterized by microarray and serum metabonome were determined by 1H nuclear magnetic resonance (NMR) spectroscopy. A total of 243 differentially expressed genes (DEGs) were identified, among which 141 genes were up-regulated and 102 genes were down-regulated. Metabonomics revealed significant changes in concentrations of creatine, pyruvate, glutamine, lysine, choline, acetate, lipids, taurine and trimethylamine oxide. Four biological pathways were identified by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis where both gene expression and metabolite concentrations were altered in response to DSW exposure. These results highlight the significance of combined use of transcriptomic and metabonomic approaches in evaluating potential health risk induced by DSW contaminated with various hazardous materials.
2012-01-01 | GSE30940 | GEO
Project description:Comammox amoA sequencing of 17 environmental samples
| PRJNA509063 | ENA
Project description:Study of enrichment of comammox amoA gene
Project description:Concentration- and time-dependent genomic changes in the mouse urinary bladder following exposure to arsenate in drinking water for up to twelve weeks. Inorganic arsenic (Asi) is a known human bladder carcinogen. The objective of this study was to examine the concentration dependence of the genomic response to Asi in the urinary bladders of mice. C57BL/6J mice were exposed for 1 or 12 weeks to arsenate in drinking water at concentrations of 0.5, 2, 10, and 50 mg As/L. Urinary bladders were analyzed using gene expression microarrays. A consistent reversal was observed in the direction of gene expression change: from predominantly decreased expression at 1 week to predominantly increased expression at 12 weeks. These results are consistent with evidence from in vitro studies of an acute adaptive response that is suppressed on longer exposure due to down-regulation of Fos. Pathways with the highest enrichment in gene expression changes were associated with epithelial-to-mesenchymal transition, inflammation, and proliferation. Benchmark dose (BMD) analysis determined that the lowest median BMD values for pathways were above 5 mg As/L, despite the fact that pathway enrichment was observed at the 0.5 mg As/L exposure concentration. This disparity may result from the non-monotonic nature of the concentration-responses for the expression changes of a number of genes, as evidenced by the much fewer gene expression changes at 2 mg As/L compared to lower or higher concentrations. Pathway categories with concentration-related gene expression changes included cellular morphogenesis, inflammation, apoptosis/survival, cell cycle control, and DNA damage response. The results of this study provide evidence of a concentration-dependent transition in the mode of action for the subchronic effects of Asi in mouse bladder cells in the vicinity of 2 mg Asi/L.
Project description:Ground water Arsenic (As) toxicity is a global problem and millions of people are exposed to elevated levels (more than WHO advised maximum limit of 10µg/L) through drinking water. The exposure is associated with various cancerous and non-cancerous diseases. It may alter DNA methylation profiles of inviduals and suppress the activity of various genes giving rise to different diseases. Pakistan, a developing country in South Asian region, also has reported elevated ground water As levels in various investigations since 2005. However, a very limited biomonitoring studies have been conducted in this context while no study reports molecular changes associated with drinking water As exposure in Pakistan. Within this context, the present study aimed to investigate genome-wide DNA methylation profiles of the exposed subjects in two districts of Punjab Province Pakistan, i.e Lahore and Kasur. The population was stratified into three exposure groups comprising Low, Medium and High exposure based on their urinary arsenic levels. Genome-wide DNA methylation profiles were obtained using MeDIP in combination with NimbleGen 2.1M Deluxe Promotor arrays.