Project description:The postnatal development of the mouse is characterized by a stress hyporesponsive period (SHRP), where basal corticosterone levels are low and responsiveness to mild stressors is reduced. Maternal separation is able to disrupt the SHRP and is widely used to model early trauma. In this study we aimed at identifying of brain systems involved in acute and possible long-term effects of maternal separation. We conducted a microarray-based gene expression analysis in the hypothalamic paraventricular nucleus after maternal separation, which revealed 52 differently regulated genes compared to undisturbed controls, among them are 37 up-regulated and 15 down-regulated genes. One of the prominently unregulated genes, angiotensinogen, was validated using a in-situ hybridization. Angiotensinogen is the precursor of angiotensin II the main effector of the brain renin-angiotensin system (RAS), which is known to be involved in stress system modulation in adult animals. Using the selective angiotensin type I receptor (AT(1)) antagonist candesartan we found strong effects on CRH and GR mRNA expression in the brain and ACTH release following maternal separation. AT(1) receptor blockade appears to enhance central effects of maternal separation in the neonate, suggesting a suppressing function of brain RAS during the SHRP. Taken together, our results illustrate the molecular adaptations that occur in the paraventricular nucleus following maternal separation and identify signaling cascades, that control stress system activity in the neonate. Keywords: phenotype Litters were randomly assigned to either a maternally non-separated or 24 hour maternally separated condition. At the time of testing, all pups from a litter were sacrificed immediately by decapitation.
Project description:The postnatal development of the mouse is characterized by a stress hyporesponsive period (SHRP), where basal corticosterone levels are low and responsiveness to mild stressors is reduced. Maternal separation is able to disrupt the SHRP and is widely used to model early trauma. In this study we aimed at identifying of brain systems involved in acute and possible long-term effects of maternal separation. We conducted a microarray-based gene expression analysis in the hypothalamic paraventricular nucleus after maternal separation, which revealed 52 differently regulated genes compared to undisturbed controls, among them are 37 up-regulated and 15 down-regulated genes. One of the prominently unregulated genes, angiotensinogen, was validated using a in-situ hybridization. Angiotensinogen is the precursor of angiotensin II the main effector of the brain renin-angiotensin system (RAS), which is known to be involved in stress system modulation in adult animals. Using the selective angiotensin type I receptor (AT(1)) antagonist candesartan we found strong effects on CRH and GR mRNA expression in the brain and ACTH release following maternal separation. AT(1) receptor blockade appears to enhance central effects of maternal separation in the neonate, suggesting a suppressing function of brain RAS during the SHRP. Taken together, our results illustrate the molecular adaptations that occur in the paraventricular nucleus following maternal separation and identify signaling cascades, that control stress system activity in the neonate. Keywords: phenotype
Project description:Renin-angiotensin system (RAS) inhibition reduces stroke and improves brain capillary integrity in stroke prone spontaneously hypertensive rats (SHRSP). We tested the hypothesis that treatment with an angiotensin II receptor subtype 1 (AT1R) antagonist has different effects, compared to an angiotensin converting enzyme (ACE) inhibitor, on gene expression in blood-brain barrier (BBB) capillaries. Six weeks old SHRSP were treated with either olmesartan (4 mg/kg, n=20), lisinopril (6 mg/kg , n=20) or remained untreated (n=20). Blood pressure was controlled by tail-cuff measurement. After 5 weeks the animals were sacrificed and cerebral capillaries were isolated. mRNA was extracted and analyzed with rat GeneChip DNA arrays. Additionally, brain histology and monocyte/macrophage infiltrates were determined. Both treatments similarly reduced neurological signs of stroke, stroke mortality, and monocyte/macrophage infiltration, compared to controls. Blood pressure was not influenced significantly by both drugs. We found 42 transcripts that were regulated by both treatments in the same manner. These genes were mostly related to inflammation. We also observed 39 differentially expressed genes between the two treatment groups that typically contribute to cell growth and differentiation. This study demonstrates that, despite similar effects on cerebral pathology and outcome, ACE inhibition and AT1R blockade have distinct molecular effects on gene expression in BBB capillaries.
Project description:The brain renin-angiotensin system (RAS) stimulates resting metabolic rate in part through a mechanism involving suppression of the circulating RAS. This effect appears to be mediated through a reduction in angiotensin AT2 receptor (AT2R) signaling within inguinal fat. To examine the molecular mechanisms underlying this effect, mice with hyperactivity of the brain RAS (“sRA” mice, expressing human renin via the synapsin promoter and human angiotensinogen via its own promoter) and littermate controls were chronically infused with vehicle or the AT2R specific agonist, CGP-42112a (CGP, 90 ng/hr, 8 wk, sc). To identify altered signaling pathways, total RNA was isolated from inguinal adipose tissue and transcript abundance was quantitated by RNA-Seq.
Project description:We inflicted TBI to chemokine-deficient mouse lines in order to establish involvement of various signalling pathways that may be addressed therapeutically. Interacting chemokine pathways in brain regulate distinct inflammatory cells. Activated microglia are separate from invading phagocytes and dendritic cells. Findings show potential targets to interfere with specific inflammatory responses after brain injury.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
Project description:LC-MS/MS Proteomics was performed to determine proteomic differences between colon adenocarcinoma (CA) tissues and patient-matched normal colon tissues, CA-derived primary cell lines and NC-derived primary cells, and between LGCA tissues and cell lines and HGCA tissues and cell lines. Biological processes which may link the renin-angiotensin system and CA were investigated, revealing enrichment of various signalling pathways that may play roles in CA onset and progression directly or via the renin-angiotensin system.
Project description:The role of the renin-angiotensin system in chronic kidney disease involves multiple peptides and receptors. Exerting antipodal pathophysiological mechanisms, renin inhibition and AT1 antagonism ameliorate renal damage. This is a comparison between the renin inhibitor aliskiren with the At1 antagonist losartan in mice with chronic kidney disease due to renal ablation.
Project description:SILAC based protein correlation profiling using size exclusion of protein complexes derived from seven Mus musculus tissues (Heart, Brain, Liver, Lung, Kidney, Skeletal Muscle, Thymus)
Project description:Renin-angiotensin system (RAS) inhibition reduces stroke and improves brain capillary integrity in stroke prone spontaneously hypertensive rats (SHRSP). We tested the hypothesis that treatment with an angiotensin II receptor subtype 1 (AT1R) antagonist has different effects, compared to an angiotensin converting enzyme (ACE) inhibitor, on gene expression in blood-brain barrier (BBB) capillaries. Six weeks old SHRSP were treated with either olmesartan (4 mg/kg, n=20), lisinopril (6 mg/kg , n=20) or remained untreated (n=20). Blood pressure was controlled by tail-cuff measurement. After 5 weeks the animals were sacrificed and cerebral capillaries were isolated. mRNA was extracted and analyzed with rat GeneChip DNA arrays. Additionally, brain histology and monocyte/macrophage infiltrates were determined. Both treatments similarly reduced neurological signs of stroke, stroke mortality, and monocyte/macrophage infiltration, compared to controls. Blood pressure was not influenced significantly by both drugs. We found 42 transcripts that were regulated by both treatments in the same manner. These genes were mostly related to inflammation. We also observed 39 differentially expressed genes between the two treatment groups that typically contribute to cell growth and differentiation. This study demonstrates that, despite similar effects on cerebral pathology and outcome, ACE inhibition and AT1R blockade have distinct molecular effects on gene expression in BBB capillaries. Keywords = angiotensin II Keywords = gene expression Keywords = microarrays Keywords = brain capillaries Keywords = SHRSP Keywords = olmesartan Keywords = lisinopril Keywords: other