Project description:Heat illness, which remains an occupational and environmental hazard, can be caused by excessive strain or heat load in combination with other factors. In the 10-year period from 1999 to 2009, an average of 658 annual heat-related deaths occurred in the United States. While heat stress at the cellular level has been studied, a paucity of risk assessment and injury biomarkers as well as therapeutic interventions remains. To identify novel biomarkers and to further understand the molecular mechanisms of heat stress, we identified differentially expressed microRNAs (miRNAs) in the heart, liver, and kidney from a conscious rat model at three time points. We distinguished the effect in animals with histopathological evidence of heart injury from those without evidence of organ injury. In animals without evidence of injury, we identified a total of 45 unique modulated miRNAs, whereas in the three animals with evidence of injury, we identified 171 unique differentially expressed miRNAs. The majority of the perturbed miRNAs were both time and tissue specific. Using the data from a microarray companion study, we identified the mRNAs that are the predicted targets of the differentially expressed miRNAs and performed pathway enrichment analysis. The enrichment analysis suggested that the perturbed miRNAs are involved in biological pathways related to energy metabolism, the unfolded protein response, and organ injury. These miRNAs may serve as organ-specific heat stress biomarkers of exposure or effect, as well as identify potential targets of heat illness prevention. Heart, liver, lung and kidney tissue was collected from rats at Tc,max and at 24 and 48 h for both heat exposed rats (n=4 to 6) or time matched, unheated controls (n= 4 to 6)
Project description:Heat illness, which remains an occupational and environmental hazard, can be caused by excessive strain or heat load in combination with other factors. In the 10-year period from 1999 to 2009, an average of 658 annual heat-related deaths occurred in the United States. While heat stress at the cellular level has been studied, a paucity of risk assessment and injury biomarkers as well as therapeutic interventions remains. To identify novel biomarkers and to further understand the molecular mechanisms of heat stress, we identified differentially expressed microRNAs (miRNAs) in the heart, liver, and kidney from a conscious rat model at three time points. We distinguished the effect in animals with histopathological evidence of heart injury from those without evidence of organ injury. In animals without evidence of injury, we identified a total of 45 unique modulated miRNAs, whereas in the three animals with evidence of injury, we identified 171 unique differentially expressed miRNAs. The majority of the perturbed miRNAs were both time and tissue specific. Using the data from a microarray companion study, we identified the mRNAs that are the predicted targets of the differentially expressed miRNAs and performed pathway enrichment analysis. The enrichment analysis suggested that the perturbed miRNAs are involved in biological pathways related to energy metabolism, the unfolded protein response, and organ injury. These miRNAs may serve as organ-specific heat stress biomarkers of exposure or effect, as well as identify potential targets of heat illness prevention.
Project description:In order to establish a rat embryonic stem cell transcriptome, mRNA from rESC cell line DAc8, the first male germline competent rat ESC line to be described and the first to be used to generate a knockout rat model was characterized using RNA sequencing (RNA-seq) analysis.
Project description:Analysis of LBNF1 rat testes from controls, containing both somatic and all germ cell types and from irradiated rats in which all cells germ cells except type A spermatgogonia are eliminated. Results provide insight into distinguishing germ and somatic cell genes and identification of somatic cell genes that are upregulated after irradiation.