Myocardial expression data from wild-type and akt2-/- mice
Ontology highlight
ABSTRACT: Wild-type (WT) C57Bl/6 and akt2-/- male mice. Keywords: RNA Expression Array Left ventricles (LV) from 12-16 week-old male wild type mice and age-matched akt2-/- mice
Project description:Specific pathogen free wild-type C57Bl/6 male mice fed ketogenic diet (Bio-Serv AIN-76-A) for 4 weeks Keywords: RNA Expression Array Hearts from 12 week-old mice that were maintained on a standard polysacchardide-rich chow until the age of 8 weeks, at which time they were switched to a ketogenic diet (ad libitum) and maintained for 4 additional weeks prior to collection of tissues
Project description:Lentiviral vector (LV)-mediated gene transfer is a promising method of gene therapy. We previously reported that systemic injection of LV triggers a transient inflammatory response. Here, we carried out studies to better characterize this response, and to develop a strategy to overcome the effects of interferon (IFN) on LV-mediated gene transfer. We profiled gene expression in the liver after LV administration using deep-sequencing, and identified several innate response pathways. We examined the response to LV in MyD88-TRIF knock-out mice, which are incapable of toll-like receptor (TLR) signaling. The IFN response to LV was not reduced in the liver, indicating that a non-TLR pathway can recognize LV in this tissue. Indeed, blocking reverse-transcription with AZT reduced the IFN response only in the liver, suggesting that proviral DNA can be a trigger. To block the inflammatory response, we pre-treated mice with a short-course of dexamethasone. At 4 hours post-treatment, all of the IFN-induced genes were normalized. By blocking the inflammatory response, hepatocyte transduction was dramatically increased, which doubled the level of human factor-IX produced by a hepatocyte-specific LV. Our studies uncover new insights into LV-induced immune responses in the liver, and provide a means to increase the safety and efficiency of LV-mediated gene transfer. mRNA profiles from livers of untreated and LV-treated mice were generated by deep-sequencing in Illumina HiSeq 2000.
Project description:Caloric Restriction in Leptin Deficiency Worsens Myocardial Steatosis: Failure to Upregulate PPAR gamma and Thermogenic Glyecrolipid/Fatty Acid Cycling Growing evidence supports an anti-lipotoxic role for leptin in preventing inappropriate peripheral tissue lipid deposition. Obese, leptin deficient ob/ob mice develop left ventricular (LV) hypertrophy and myocardial steatosis with increased apoptosis and decreased longevity. Here we investigated the cardiac effects of caloric restriction in leptin deficiency. Echocardiography was performed on C57Bl/6 wild-type mice (WT) and 7-month-old ob/ob mice fed ad lib, leptin-repleted (LR-ob/ob), or calorie-restricted (CR-ob/ob) for four weeks. Ventricular tissue was examined by electron microscopy (EM), mitochondrial coupling assay, and microarray expression profiling. LR and CR-ob/ob mice showed decreased body weight, heart weight, and LV wall thickness compared to ad lib ob/ob mice. LV fractional shortening was decreased in ad lib ob/ob mice, but restored to WT levels in LR and CR groups. However, EM revealed severe cardiac steatosis in the CR-ob/ob group compared to only moderate steatosis in ad lib ob/ob . Despite marked cardiac steatosis, CR (like LR) restored mitochondrial coupling to WT levels. CR up-regulated genes associated with oxidative stress and cell death, changes suggestive of cardiac lipotoxicity. LR, but not CR was shown to induce core genes involved in glycerolipid/free fatty acid cycling, a highly thermogenic pathway that can reduce intracellular lipid stores. LR, but not CR up-regulated and restored PGC1 and PPARto wild type levels; CR paradoxically further suppressed cardiac PPAR. Thus, leptin is essential in protecting the heart from lipotoxicity, and the inability to up-regulate the thermogenic glycerolipid/free fatty acid cycling pathway may impair the response of leptin deficient animals to the lipotoxic stress of calorie restriction. 6 month aged ob/ob mice were either leptin repleted with osmotic mini-pumps, calorie restricted to match the caloric intake of the leptin repleted mice, or fed ad lib for one month. 6-8 month C57Bl/6J mice were aged to serve as controls.
Project description:Cardiac structural changes associated with dilated cardiomyopathy (DCM) include cardiomyocyte hypertrophy and myocardial fibrosis. Connective Tissue Growth Factor (CTGF) has been associated with tissue remodeling and is highly expressed in failing hearts. To test if inhibition of CTGF would alter the course of cardiac remodeling and preserve cardiac function in the protein kinase Cε (PKCε) mouse model of DCM. Transgenic mice expressing constitutively active PKCε in cardiomyocytes develop cardiac dysfunction that was evident by 3 months of age, and that progressed to heart failure, cardiac fibrosis, and increased mortality. Beginning at 3 months of age, mice were treated with an antibody to CTGF (FG-3149) or non-immune IgG control antibody for an additional 3 months. CTGF inhibition significantly improved left ventricular (LV) systolic and diastolic function in PKCε mice, and slowed the progression of LV dilatation. Using gene arrays and quantitative PCR, the expression of many genes associated with tissue remodeling were elevated in PKCε mice, but significantly decreased by CTGF inhibition, however total collagen deposition was not attenuated. The observation of significantly improved LV function by CTGF inhibition in PKCε mice suggests that CTGF inhibition may benefit patients with DCM. Total RNA was isolated from the left ventricle of 6-month-old PKCε transgenic mice or nontransgenic FVB/N controls 3 months after initiation of treatment with IgG (n=10 biological replicates each) or anti-CTGF antibody FG-3149 (n=12 each) and hybridized to Affymetrix 430A 2.0 microarrays. CEL files were processed by GCRMA and rescaled using median per-gene normalization in GeneSpring GX 7.3.1.
Project description:The right ventricle (RV) differs in several aspects from the left ventricle (LV) including its embryonic origin, physiological role and anatomical design. In contrast to LV hypertrophy, little is known about the molecular circuits, which are activated upon RV hypertrophy (RVH). We established a highly reproducible model of RVH in mice using pulmonary artery clipping (PAC), which avoids detrimental RV pressure overload and thus allows long-term survival of operated mice. Magnetic resonance imaging revealed pathognomonic changes with striking similarities to human congenital heart disease- or pulmonary arterial hypertension- patients. Comparative, microarray based transcriptome analysis of right- and left-ventricular remodeling identified distinct transcriptional responses to pressure-induced hypertrophy of either ventricle, which were mainly characterized by stronger transcriptional responses of the RV compared to the LV myocardium. Hierarchic cluster analysis revealed a RV- and LV-specific pattern of gene activity after induction of hypertrophy, however, we did not find evidence for qualitatively distinct regulatory pathways in RV compared to LV. Data mining of nearly three thousand RV-enriched genes under PAC disclosed novel potential (co)-regulators of long-term RV remodeling and hypertrophy. We reason that specific inhibitory mechanisms in RV restrict excessive myocardial hypertrophy and thereby contribute to its vulnerability to pressure overload. Alternative splicing and gene expression analysis during development of the heart and cardiomyoyte differentiation.
Project description:5-Fluorouracil (5-Fu) and leucovorin (LV) are often given in combination to treat colorectal cancer. 5-Fu/LV prevents cell proliferation by inhibiting thymidylate synthase, which catalyzes the conversion of deoxyuridine monophosphate to deoxythymidine monophosphate. While 5-Fu has been shown to cause cognitive impairment, the synergistic effect of 5-Fu with LV has not been fully explored. The present investigation was designed to assess how the combination of 5-Fu and LV affect cognition in a murine model. Six-month-old male mice were used in this study; 15 mice received saline injections and 15 mice received 5-Fu/LV injections. One month after treatment, the elevated plus maze, Y-maze, and Morris water maze behavioral tasks were performed. Brains were then extracted, cryosectioned, and stained for CD68 to assay microglial activation and with tomato lectin to assay the vasculature. All animals were able to locate the visible and hidden platform locations in the water maze. However, a significant impairment in spatial memory retention was observed in the probe trial after the first day of hidden-platform training (first probe trial) in animals that received 5-Fu/LV, but these animals showed spatial memory retention by day 5. There were no significant increases in inflammation as measured by CD68, but 5-Fu/LV treatment did modulate blood vessel morphology. Tandem mass tag proteomics analysis identified 6,049 proteins, 7 of which were differentially expressed with a P-value of < 0.05 and a fold change of >1.5. The present data demonstrate that 5-Fu/LV increases anxiety and significantly impairs spatial memory retention.
Project description:The use of polypharmacy (5 or more concurrent medications) is common in older patients, particularly those with cardiovascular diseases. However, polypharmacy is associated with adverse geriatric outcomes, including increased risks in fall and frailty. Both ageing and sex influence pharmacological response and cardiac physiology. The mechanistic intersect between age, sex, and drug-drug interaction is poorly understood. Previously, we have developed a polypharmacy murine model whereby young (4 months) and old (23 months) healthy C57BL/6JArc mice of both sexes were randomised to either polypharmacy or control. The polypharmacy regimen has a High Drug Burden Index (HDBI) and contains 3 medications with anticholinergic/sedative medications (oxybutynin, oxycodone, citalopram) along with cardiovascular medications (simvastatin and metoprolol). Medications were given at oral therapeutic doses. HDBI has clinically been demonstrated to be particularly associated with adverse geriatric outcomes. Here, we profiled the left ventricular (LV) proteome following 10 weeks of HDBI polypharmacy treatment along with age- and sex-matched controls.
Project description:OBJECTIVE: To understand the molecular pathways underlying the cardiac preconditioning effect of short-term caloric restriction (CR). BACKGROUND: Lifelong CR has been suggested to reduce the incidence of cardiovascular disease through a variety of mechanisms. However, prolonged adherence to a CR life-style is difficult. Here we show how short-term CR protects the mouse heart from ischemia. METHODS: Male 10-12 wk old C57bl/6 mice were randomly assigned to an ad libitum (AL) diet with free access to regular chow, or CR, receiving 30% less food over a period of 7 days (d), prior to myocardial infarction (MI) via permanent coronary ligation. Prior to MI (d8), the left ventricles (LV) of AL and CR mice were collected for Western blot, DNA and microRNA (miR) analyses. In separate groups, infarct size, cardiac hemodynamics and protein abundance of caspase 3 was measured at d2 post-MI. RESULTS: This short-term model of CR was associated with cardio-protection, as evidenced by decreased infarct size (18.5±2.4% vs. 26.6±1.7%, N=10/group; P=0.01). cDNA and miR profiles pre-MI (N=5/group) identified genes modulated by short-term CR to be associated with circadian clock, oxidative stress, immune function, apoptosis, metabolism, angiogenesis, cytoskeleton and extracellular matrix (ECM). Western blots pre-MI revealed CR-associated increases in phosphorylated Akt and GSK3ß, reduced levels of phosphorylated AMPK and mitochondrial related proteins PGC-1?, cytochrome C and cyclooxygenase (COX) IV, with no differences in the levels of phosphorylated eNOS or MAPK (ERK1/2; p38). CONCLUSIONS: Short-term CR for only 7d represents a preconditioning strategy that limits infarct size. It is associated with a unique gene and miR signature, including the activation of specific pro-survival kinases. These findings may have implications for therapeutic use of short-term CR. . Male 12 wk-old C57Bl/6 mice were obtained from Charles River (Montreal, PQ, Canada) and maintained for at least 2 weeks before experimentation. Animals were randomly assigned to AL, CR and Lira groups with no initial differences in body weights. AL group mice were allowed ad libitum diet. Lira group mice were injected with Liraglutide (Glucagon-like peptide-1 agonist) at a dose of 200 µg/Kg i.p., twice daily for 7 days which is a mild weight-loss inducing dose and had access to ad libitum food and water. CR group mice were put on a Caloric restriction diet (30% less than normal ad libitum caloric intake) for 7 days to induce weight loss comparable to Lira group mice. Mice for CR and AL were individually caged and their food intake was measured everyday between 10-11 am for 1 week to calculate the average daily food intake. CR mice were fed 30% less than the calculated mean daily AL food consumption. CR cages were inspected daily for any remaining food, and transferred to a new cage every day. For CR group, pre-weighed mouse chow pellets were placed in cages between 10-11 am every day. Body weights were recorded between 10-11 am before and after the 7 day study period. For pre-ischemic assessments, animals (n=5/group/assessment) were sacrificed on day-8 (pre-MI), hearts were immediately extracted, washed in sterile phosphate-buffered saline (PBS), with LV free walls dissected, snap frozen in liquid nitrogen and stored at -80o C.
Project description:The hypothesis was tested that the Pbx1-d isoform was responsible for the Sle1a.1 phenotypes in CD4+ T cells. Jurkat T cells were transfected with a lentiviral construct expressing Pbx1-d-GFP or control RFP. Pbx1-d over-expression reduced the percentage of late apoptotic cells in response to anti-CD3 and anti-CD28 stimulation as compared with control-Lin28-transfected cells. Overall, these data demonstrate that over-expression of Pbx1-d results in an activated/inflammatory phenotype and in a defective response to RA in Jurkat T cells, strongly suggesting that the increased expression of Pbx1-d is responsible for the Sle1a.1 phenotypes. Jurkat T cells (5 x 105 cells/ml) were transfected with an lentiviral (LV) vector expressing either control (RFP or Lin28) or Pbx1-d-GFP. Total RNA was extracted from GFP+ or RFP+ FACS-sorted Jurkat T cells transfected LV-GFP-Pbx1-d or LV-RFP, as well as non-transfected cells in 4 independent transfections per group.