Project description:Purpose : Identification of novel microRNA biomarkers in urine and plasma from rats with kidney or liver damage micoRNA-SEQ was used to analyze changes in miRNA profiles of tissue, plasma and urine samples of rats treated with either a nephrotoxicant (cisplatin) or one of two hepatotoxicants (Acetaminophen [APAP] or Carbon Tetrachloride [CCL4]).
Project description:Preclinical biomarkers useful for identification of idiosyncratic drugs have not been identified. It is hypothesized that patterns of transcript expression for the hepatotoxicants, including classical and idiosyncratic hepatotoxicants, are similar and the patterns differ from those of non-hepatotoxicants. This experiment is part of the biomarkers study, and focus on two clasical hepatotoxicants: Acetaminophen and Carbon tetrachloride. We have employed whole genome microarray expression profiling to identify liver gene expression changes induced by hepatotoxicants. For the same animal, urinary microRNA profiling were analyzed. APAP and CCl4 both significantly increased the urinary levels of 44 and 28 miRNAs, respectively. In addition, 10 of the increased miRNAs were in common between APAP and CCl4. Computational analysis was used to predict target genes of the 10 shared hepatotoxicant-induced miRNAs. From the same animals, liver gene expression profiling was performed using whole genome microarrays. Eight putative target genes were found to be significantly altered in the liver of APAP and CCl4 treated animals. Acetaminophen induced liver gene expression changes in rats (Six to seven week-old male Sprague-Dawley rats, provided by the US Food and Drug Administration National Center for Toxicological Research (NCTR) breeding colonies, were used for the study.) were measured at 6 hours, 24 hours, 3 days and 7 days after exposure to doses of 0, 100 and 1250 mg/kg. Carbon tetrachloride induced liver gene expression changes in rats were measured at 6 hours, 24 hours and 3 days after exposure to doses of 0, 50 and 2000 mg/kg. Each group has at least 4 animals, total of 96 samples.
Project description:Living organisms are intricate systems with dynamic internal processes. Their RNA, protein, and metabolite levels fluctuate in response to variations in health and environmental conditions. Among these, RNA expression is particularly accessible for comprehensive analysis, thanks to the evolution of high throughput sequencing technologies in recent years. This progress has enabled researchers to identify unique RNA patterns associated with various diseases, as well as to develop predictive and prognostic biomarkers for therapy response. Such cross-sectional studies allow for the identification of differentially expressed genes (DEGs) between groups, but they have limitations. Specifically, they often fail to capture the temporal changes in gene expression following individual perturbations and may lead to significant false discoveries due to inherent noise in RNA sequencing sample preparation and data collection. To address these challenges, our study hypothesized that frequent, longitudinal RNA sequencing (RNAseq) analysis of blood samples could offer a more profound understanding of the temporal dynamics of gene expression in response to drug interventions, while also enhancing the accuracy of identifying genes influenced by these drugs. In this research, we conducted RNAseq on 829 blood samples collected from 84 Sprague-Dawley lab rats. Excluding the control group, each rat was administered one of four different compounds known for liver toxicity: tetracycline, isoniazid, valproate, and carbon tetrachloride. We developed specialized bioinformatics tools to pinpoint genes that exhibit temporal variation in response to these treatments.
Project description:Differential gene expression in mice liver after carbon tetrachloride and acetaminophen administration. Livers from control mice were compared with drug treated mice livers at different time points. Keywords: Time-course
Project description:Preclinical biomarkers useful for identification of idiosyncratic drugs have not been identified. It is hypothesized that patterns of transcript expression for the hepatotoxicants, including classical and idiosyncratic hepatotoxicants, are similar and the patterns differ from those of non-hepatotoxicants. This experiment is part of the biomarkers study, and focus on two clasical hepatotoxicants: Acetaminophen and Carbon tetrachloride. We have employed whole genome microarray expression profiling to identify liver gene expression changes induced by hepatotoxicants. For the same animal, urinary microRNA profiling were analyzed. APAP and CCl4 both significantly increased the urinary levels of 44 and 28 miRNAs, respectively. In addition, 10 of the increased miRNAs were in common between APAP and CCl4. Computational analysis was used to predict target genes of the 10 shared hepatotoxicant-induced miRNAs. From the same animals, liver gene expression profiling was performed using whole genome microarrays. Eight putative target genes were found to be significantly altered in the liver of APAP and CCl4 treated animals.