DNA methylation in Syrian hamster female fetal cells (gestation day 13.5) exposed in vitro to 5-aza-2’deoxycytidine (5aCdR)
Ontology highlight
ABSTRACT: Purpose: To validate the reduced representation bisulfite sequencing (RRBS) methodology by comparing DNA methylation pattern in Syrian hamster fetal (SHF) primary cells to a SHF cell line (MT2) exposed to the DNA methyl transferase inhibitor,5aCdR. The MT2 cell line was originally derived from the expansion of a benzo[a]pyrene-induced morphologically transformed clone (Pickles et al 2016. Mutat.Res.Genet.Toxicol.Environ Mutagen. 802:50-58).
Project description:Transcriptional profiling of male Syrian hamster testes, comparing control animals with those that have had a pinealectomy. Keywords: transcriptional profiling Two-condition experiment, Control vs pinealectomised animals
Project description:Transcriptional profiling of male Syrian hamster testes, comparing control animals with those that have had a pinealectomy. Keywords: transcriptional profiling
Project description:1. The experiment was performed to assess if the newly discovered Syrian hamster specific anti-PD-L1 antibody could induce a biologically relevant change in transcriptome profile in the tumours. This would confirm that the antibody has functional properties. In the larger picture, the Syrian Hamster model is favored over the mouse model for the development of vaccines and testing of oncolytic viruses/immunotherapies. This is because the model is semi permissive to virus replication compared to the mouse model. We can therefore more reliably assess the efficacy of oncolytic virotherapies, mainly oncolysis and promoter specific transgene expression. Moreover, we wanted to test potential improvements to treatment outcomes when combining oncolytic virotherapy and immune checkpoint blockade. However, there are not many commercially available research tools specific to the Syrian Hamster. This is why we developed an in vivo compatible immune checkpoint inhibitor so that we could assess the combination therapy in the Syrian hamster model. Lastly, we also wanted to validate if we could assess the efficacy of the immunotherapies using biopsies from hamsters to remove unnecessary use of animals. 2. To do this, we engrafted one PDAC tumours on the right flank of Syrian hamsters using 5 x10E+6 HapT1 cells grown in culture. When tumours reached 4-5mm in diameter, the hamsters were injected intraperitoneally with either 300ug of IgG2a control or anti-PD-L1 (clone;11B12-1). Hamsters were treated 8 times and a tumour biopsy was taken one day before the last treatment. The biopsy was immediately stored in RNA-later until extraction with RNA mini kit (Qiagen).
Project description:Using microarray analyses and subsequent verification by RT-PCR, we studied the changes in gene expression in the inferior colliculus after an ictal event in one models of audiogenic epilepsy, genetic audiogenic seizure hamster (GASH:Sal). GASH:Sal, a hamster strain developed at the University of Salamanca, exhibits genetic audiogenic epilepsy similar to human Grand Mal epilepsy. GASH:Sal shows an autosomal recessive inheritance for susceptibility to audiogenic seizures, which manifest more severely in young animals; the seizure severity progressively declines with age. Genetic animal models of epilepsy are an important tool for further understanding the basic cellular mechanisms underlying epileptogenesis and for developing novel antiepileptic drugs. We conducted a comparative study of gene expression in the inferior colliculus, a nucleus that triggers audiogenic seizures, using two animal models, the Wistar audiogenic rat (WAR) and the genetic audiogenic seizure hamster (GASH:Sal). For this purpose, both models were subjected to auditory stimulation, and 60 minutes after stimulation, the inferior colliculi were collected. As a control, intact Wistar rats and Syrian hamsters were subjected to identical stimulation and tissue preparation protocols to those performed on the experimental animals. A total of 24 animals were used in this study according to the following distribution: 12 control Syrian hamsters (Mesocricetus auratus) and 12 GASH:Sal at 16 weeks of age and a body weight of approximately 60 g. Six animals Syrian and GASH:Sal hamsters, respectively, were exposed to auditory stimulation, and 60 min after the seizures, we harvested the IC for all gene expression analyses (stimulated Syrian hamsters and stimulated GASH:Sal hamsters). As controls, other six animals Syrian and GASH:Sal hamsters, respectively, were not exposed to the same stimulation (Syrian hamsters and GASH:Sal hamsters).
Project description:Purpose: To use reduced representaion bisulfite sequencing to measure differential genome methylation among: 1. cells treated with benzo[a]pyrene (B[a]P) versus vehicle alone (DMSO) using the Syrian Hamster Cell Transformation Assay method; 2. cells originating from normal (Nc) versus morphologically transformed (MTc) colonies; 3. cells in senescence (SEN) versus those that have bypassed senescence (SENbp).
Project description:Hibernation consist of alternating torpor/arousal phases, during which animals cope with repetitive hypothermia and ischemia-reperfusion. Due to limited transcriptomic and methylomic information for facultative hibernators, we here conducted RNA and whole genome bisulfite sequencing in liver of hibernating Syrian hamster (Mesocricetus auratus). Gene Ontology analysis was performed on 844 differentially expressed genes (DEGs) and confirmed the shift in metabolic fuel utilization, inhibition of RNA transcription and cell cycle regulation as found in seasonal hibernators. We show a so far unreported suppression of MAPK and PP1 pathways. Notably, hibernating hamsters showed upregulation of MAPK inhibitors (DUSPs and SPRYs) and reduced levels of MAPK induced transcription factors. Promoter methylation was found to modulate the expression of genes targeted by these transcription factors. In conclusion, we document gene regulation between hibernation phases, which may aid the identification of pathways and targets to prevent organ damage in transplantation or ischemia-reperfusion.
Project description:Hibernation consist of alternating torpor/arousal phases, during which animals cope with repetitive hypothermia and ischemia-reperfusion. Due to limited transcriptomic and methylomic information for facultative hibernators, we here conducted RNA and whole genome bisulfite sequencing in liver of hibernating Syrian hamster (Mesocricetus auratus). Gene Ontology analysis was performed on 844 differentially expressed genes (DEGs) and confirmed the Liver, shift in metabolic fuel utilization, inhibition of RNA transcription and cell cycle regulation as found in seasonal hibernators. We Liver, show a so far unreported suppression of MAPK and PP1 pathways. Notably, hibernating hamsters Liver, showed upregulation of MAPK inhibitors (DUSPs and SPRYs) and reduced levels of MAPK induced transcription factors. Promoter methylation was found to modulate the expression of genes targeted by these transcription factors. In conclusion, we document gene regulation between hibernation phases, which may aid the identification of pathways and targets to prevent organ damage in transplantation or ischemia-reperfusion.
Project description:This SuperSeries is composed of the SubSeries listed below. Purpose: Historically, the Syrian Hamster Embryo - cell transformation assay (SHE-CTA) has provided a method to predict the carcinogenicity of test chemicals. Note that the cells harvested for the SHE-CTA are from fetuses at gestation day 13.5 and not from embryos as historically recorded. This method has been criticized for insufficient mechanistic understanding and subjective assessment of colonies morphological transformation. A more objective method is needed that additionally provides mode of action information. A possible mode of action of carcinogens includes disruption of DNA methylation in gene regulatory regions and consequent changes in gene expression. Such genetic loci could provide biomarkers to assist in predicting the carcinogenicity of both genotoxic and non-genotoxic chemicals acting through DNA methylation disruption.
Project description:Pre-existing comorbidities such as obesity or metabolic diseases can adversely affect the clinical outcome of COVID-19. Chronic metabolic disorders are globally on the rise and often a consequence of an unhealthy diet, referred to as a Western Diet. For the first time in the Syrian hamster model, we demonstrate the detrimental impact of a continuous high-fat high-sugar diet on COVID-19 outcome. We observed increased weight loss and lung pathology, such as exudate, vasculitis, hemorrhage, fibrin, and edema, delayed viral clearance and functional lung recovery, and prolonged viral shedding. This was accompanied by and increased trend of systemic IL-10 and IL-6, as well as a dysregulated serum lipid response dominated by polyunsaturated fatty acid-containing phosphatidylethanolamine, recapitulating cytokine and lipid responses associated with severe human COVID-19. Our data support the hamster model for testing restrictive or targeted diets and immunomodulatory therapies to mediate the adverse effects of metabolic disease on COVID-19.