Project description:Adipose tissue is a major target of GH action. GH stimulates lipolysis and reduces fat mass. The molecular mechanism underlying cellular and metabolic effects of GH in adipose tissue is not well understood. The aim of this study is to identify GH-responsive genes that regulate lipid metabolism in adipose tissue. Eight men with GH deficiency underwent measurement of plasma free fatty acid (FFA), whole body lipid oxidation and fat biopsies before and after one month of GH treatment (0.5mg/day). Gene expression profiling was performed using Agilent 44K G4112F arrays utilising a two-colour design. Differentially expressed genes were identified using an empirical Bayes, moderate t-test, with a false discovery rate of < 5%. Genes involved in GH receptor signalling, lipolysis, triglyceride biosynthesis, adipocyte differentiation and function were analysed. Target genes were validated by quantitative RT-PCR. GH increased circulating IGF-I and FFA and stimulated fat oxidation. A total of 246 genes were differentially expressed, of which 135 were up-regulated and 111 down-regulated. GH enhanced adipose tissue expression of IGF-I and SOCS3. It did not change expression of key enzymes governing lipolysis, but differentially regulated genes promoting diacylglycerol syntheses. GH repressed hydroxysteroid (11-beta) dehydrogenase 1, which activates local cortisol production, and genes encoding components of extracellular matrix that regulate inflammation. GH induced concordant change in circulating IGF-I and expression in adipose tissue. GH stimulation of lipolysis is mediated at a translational and/or post-translational level. GH suppressed genes encoding local factors regulating adipocyte differentiation, function and inflammation.
Project description:Objective Circulating plasma miRNAs have been increasingly studied in the field of pituitary neuroendocrine tumor (PitNET) research. Our aim was to discover circulating plasma miRNAs species associated with growth hormone (GH) secreting PitNETs and assess how the plasma levels of discovered miRNA candidates are impacted by SSA therapy and whether there is a difference in their levels between GH secreting PitNETs and other PitNET types. Methods miRNA candidates were discovered using the whole miRNA sequencing approach and differential expression analysis. Selected miRNAs were then analyzed using real-time polymerase chain reaction (qPCR). Results Whole miRNA sequencing discovered a total of 19 differentially expressed miRNAs (DEMs) in GH secreting PitNET patients' plasma 24 hours after surgery and 19 DEMs between GH secreting PitNET patients’ plasma and non-functioning (NF) PitNET patients’ plasma. Seven miRNAs were selected for further testing of which miR-625-5p, miR-503-5p miR-181a-2-3p and miR-130b-3p showed a significant downregulation in plasma after 1 month of SSA treatment. miR-181a-5p and mir-625-5p were also found to be significantly downregulated in plasma of GH secreting PitNET patients vs. NF PitNET patients. Conclusions Our study suggests that expression of plasma miRNAs miR-625-5p, miR-503-5p miR-181a-2-3p and miR-130b-3p in GH secreting PitNETs is affected by SSA treatment. Additionally, miR-625-5p and miR-181a-5p can distinguish GH secreting PitNETs from other PitNET types warranting further research on these miRNAs for treatment efficacy.
Project description:Using an oligonucleotide-based microarray analysis to study the expression of special genes in tbx5 morphants, we demonstrated that GH and some GH-related genes were markedly downregulated.
Project description:We generated h-hepatocyte chimeric mice with livers that were predominantly repopulated with h-hepatocytes in a h-growth hormone (GH)-deficient state. Using microarray profiles, comparison between h-hepatocytes from h-GH-treated and untreated mice identified 14 GH-up-regulated and four GH-down-regulated genes, including IGF-1, SOCS2, NNMT, IGFLS, P4AH1, SLC16A1, and SRD5A1, and FADS1 and AKR1B10, respectively.
Project description:Purpose: Identify differentially expressed genes in pig lung, compared to growth on chocolate agar plate. Methods: In order to study the gene expression at this location, we sequenced ex vivo and in vivo H. parasuis transcriptome using a metatranscriptomic approach. Gene expression was compared with conventional plate culture. Results: down-regulation of anabolic and catabolic pathways, coupled with up-regulation of membrane-related genes involved in carbon acquisition, iron binding and pathogenesis. Conclusions: This data sheds some light on the scarcely studied in vivo transcriptome of H. parasuis, revealing nutritional virulence as an adaptive strategy for host survival.
Project description:This study, using a growth hormone (GH)-deficient dwarf animal model and peripheral GH replacement, investigated the effects of circulating IGF-1 during adolescence on IGF-1 levels in the brain. Our results demonstrated that hippocampal IGF-1 protein concentrations during adolescence are highly regulated by circulating IGF-1, which were reduced by GH deficiency and restored by systematic GH replacement. In contrast, IGF-1 levels in the CSF were decreased by GH deficiency but not restored by GH replacement. Furthermore, analysis of gene expression using microarrays and RT-PCR indicated that circulating IGF-1 levels did not modify the transcription of IGF-1 or its receptor in the hippocampus but did regulate genes that are involved in microvascular structure and function, brain development, and synaptic plasticity, which potentially support brain structures involved in cognitive function during this important developmental period.
Project description:Metatranscriptomic and metaproteomic analysis of C.quadricolor symbiotic bacteria for discovery of new potential biosynthetic clusters
Project description:Sex differences in liver gene expression are dictated by sex-differences in circulating growth hormone (GH) profiles. Presently, the pituitary hormone dependence of mouse liver gene expression was investigated on a global scale to discover sex-specific early GH response genes that might contribute to sex-specific regulation of downstream GH targets and to ascertain whether intrinsic sex-differences characterize hepatic responses to plasma GH stimulation. RNA expression analysis using 41,000-feature microarrays revealed two distinct classes of sex-specific mouse liver genes: genes subject to positive regulation (class-I) and genes subject to negative regulation by pituitary hormones (class-II). Genes activated or repressed in hypophysectomized (Hypox) mouse liver within 30-90min of GH pulse treatment at a physiological dose were identified as direct targets of GH action (early response genes). Intrinsic sex-differences in the GH responsiveness of a subset of these early response genes were observed. Notably, 45 male-specific genes, including five encoding transcriptional regulators that may mediate downstream sex-specific transcriptional responses, were rapidly induced by GH (within 30min) in Hypox male but not Hypox female mouse liver. The early GH response genes were enriched in 29 male-specific targets of the transcription factor Mef2, whose activation in hepatic stellate cells is associated with liver fibrosis leading to hepatocellular carcinoma, a male-predominant disease. Thus, the rapid activation by GH pulses of certain sex-specific genes is modulated by intrinsic sex-specific factors, which may be associated with prior hormone exposure (epigenetic mechanisms) or genetic factors that are pituitary-independent, and could contribute to sex-differences in predisposition to liver cancer or other hepatic pathophysiologies.
Project description:Since aerobic glycolysis has been first observed in tumors almost a century ago by Otto Warburg, the field of cancer cell metabolism sparked the interest of scientists around the world as it might offer new avenues of treatments for malignant cells. Our current study claims the discovery of Gnetin-H (GH) as a novel glycolysis inhibitor that can decrease metabolic activity and lactic acid synthesis and displays a strong cytostatic effect in melanoma and glioblastoma cells. Compared to most of the other glycolysis inhibitors used in combination with the complex-1 mitochondrial inhibitor Phenformin, GH more potently inhibited cell growth. RNA-Seq with the T98G glioblastoma cell line treated with GH showed more than an 80-fold reduction in Thioredoxin Interacting Protein (TXNIP) expression indicating that GH has a direct effect in regulating a key gene involved in the homeostasis of cellular glucose. GH in combination with Phenformin also substantially enhanced levels of p-AMPK, a marker of metabolic catastrophe. These findings suggest that the concurrent use of the glycolytic inhibitor GH with a complex-1 mitochondrial inhibitor could be used as a powerful tool to induce metabolic catastrophe in cancer cells and reduce their growth.
Project description:We have used a simple and efficient method to identify condition-specific transcriptional regulatory sites in vivo to help elucidate the molecular basis of sex-differences in transcription, which are widespread in mammalian tissues and affect normal physiology, drug response, inflammation and disease. To systematically uncover transcriptional regulators responsible for these differences, we used DNase hypersensitivity analysis coupled with high-throughput sequencing to produce condition-specific maps of regulatory sites in male and female mouse liver, and for livers of male mice feminized by continuous infusion of growth hormone (GH). We identified 71,264 hypersensitive sites, with 1,284 showing robust sex-differences. Continuous GH infusion suppressed the vast majority of male-specific sites and induced a subset of female-specific sites in male liver. We also identified broad genomic regions (up to ~100kb) showing sex-dependent hypersensitivity and similar patterns of GH response. We found a strong association of sex-specific sites with sex-specific transcription; however, a majority of sex-specific sites were >100kb from sex-specific genes. By analyzing sequence motifs within regulatory regions, we identified two known regulators of liver sexual dimorphism, and several new candidates for further investigation. This approach can readily be applied to mapping condition-specific regulatory sites in mammalian tissues under a wide variety of physiological conditions. Global DNase Hypersensitivity in male, female, and continuous growth hormone-treated male mouse liver tissue. 10 samples: Male liver (2 replicates), Female liver (2 replicates), GH-treated male liver (2 replicates), DNase digested genomic control (from male and female liver separately) and sonicated genomic control (from male and female liver separately).