scholarly journals Changes in Serum Iron and Leukocyte mRNA Levels of Genes Involved in Iron Metabolism in Amateur Marathon Runners—Effect of the Running Pace

Genes ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 460 ◽  
Author(s):  
Agata Grzybkowska ◽  
Katarzyna Anczykowska ◽  
Wojciech Ratkowski ◽  
Piotr Aschenbrenner ◽  
Jędrzej Antosiewicz ◽  
...  
Keyword(s):  
Gene Expression ◽  
Iron Metabolism ◽  
Serum Iron ◽  
Molecular Mechanisms ◽  
Mrna Levels ◽  
Marathon Runners ◽  
Time Points ◽  
Protein Levels ◽  
Reactive Protein ◽  
Blood Morphology

Iron is essential for physical activity due to its role in energy production pathways and oxygen transportation via hemoglobin and myoglobin. Changes in iron-related biochemical parameters after physical exercise in athletes are of substantial research interest, but molecular mechanisms such as gene expression are still rarely tested in sports. In this paper, we evaluated the mRNA levels of genes related to iron metabolism (PCBP1, PCBP2, FTL, FTH, and TFRC) in leukocytes of 24 amateur runners at four time points: before, immediately after, 3 h after, and 24 h after a marathon. We measured blood morphology as well as serum concentrations of iron, ferritin, and C-reactive protein (CRP). Our results showed significant changes in gene expression (except for TFRC), serum iron, CRP, and morphology after the marathon. However, the alterations in mRNA and protein levels occurred at different time points (immediately and 3 h post-run, respectively). The levels of circulating ferritin remained stable, whereas the number of transcripts in leukocytes differed significantly. We also showed that running pace might influence mRNA expression. Our results indicated that changes in the mRNA of genes involved in iron metabolism occurred independently of serum iron and ferritin concentrations.

Influence of testosterone on regulation of ODC, antizyme, and N1-SSAT gene expression in mouse kidney

2003 ◽  
Vol 285 (3) ◽  
pp. F498-F506 ◽  
Author(s):  
Olivier Levillain ◽  
Anna Greco ◽  
Jean-Jacques Diaz ◽  
Roger Augier ◽  
Anne Didier ◽  
...  
Keyword(s):  
Gene Expression ◽  
Time Course ◽  
Molecular Mechanisms ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Polyamine Biosynthesis ◽  
Testosterone Treatment ◽  
Female Mice ◽  
Protein Levels ◽  
Time Courses

Polyamines are involved in the control of the cell cycle and cell growth. In murine kidney, testosterone enhances gene expression of ornithine decarboxylase (ODC), the first enzyme in polyamine biosynthesis. In this study, we document the time course effect of testosterone on 1) gene expression of ODC, antizyme 1 (AZ1), and spermidine/spermine- N1-acetyltransferase ( N1-SSAT); 2) ODC activity in proximal convoluted tubules (PCT) and cortical proximal straight tubules (CPST); and 3) renal polyamine levels. Female mice were treated with testosterone for a period of 1, 2, 3, and 5 consecutive days. ODC gene expression was extremely low in kidneys of untreated female mice compared with that of males. Consequently, the renal putrescine level was sevenfold lower in females than in males, whereas spermidine and spermine levels did not differ between sexes. In female kidneys, testosterone treatment sharply increased ODC mRNA and protein levels as well as ODC activity. Testosterone increased the expression of ODC in PCT and CPST over different time courses, which suggests that ODC activity is differentially regulated in distinct tubules. The expression of AZ1 and N1-SSAT mRNA was similar in male and female mouse kidneys. Testosterone treatment enhanced AZ1 and N1-SSAT mRNA levels in a time-dependent manner by unknown molecular mechanisms. Putrescine and spermidine levels increased after testosterone treatment in female kidneys. Surprisingly, although ODC protein and activity were undetectable in female kidneys, the levels of AZ1 mRNA and protein were similar to those in males. Therefore, one may propose that ODC protein could be continuously degraded by AZ1 in female kidneys.

scholarly journals Comparative neurotranscriptomics reveal widespread species differences associated with bonding

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Joel A. Tripp ◽  
Alejandro Berrio ◽  
Lisa A. McGraw ◽  
Mikhail V. Matz ◽  
Jamie K. Davis ◽  
...  
Keyword(s):  
Gene Expression ◽  
Brain Region ◽  
Molecular Mechanisms ◽  
Species Differences ◽  
Cell Structure ◽  
Bond Formation ◽  
Pair Bonding ◽  
Prairie Voles ◽  
Meadow Voles ◽  
Time Points

Abstract Background Pair bonding with a reproductive partner is rare among mammals but is an important feature of human social behavior. Decades of research on monogamous prairie voles (Microtus ochrogaster), along with comparative studies using the related non-bonding meadow vole (M. pennsylvanicus), have revealed many of the neural and molecular mechanisms necessary for pair-bond formation in that species. However, these studies have largely focused on just a few neuromodulatory systems. To test the hypothesis that neural gene expression differences underlie differential capacities to bond, we performed RNA-sequencing on tissue from three brain regions important for bonding and other social behaviors across bond-forming prairie voles and non-bonding meadow voles. We examined gene expression in the amygdala, hypothalamus, and combined ventral pallidum/nucleus accumbens in virgins and at three time points after mating to understand species differences in gene expression at baseline, in response to mating, and during bond formation. Results We first identified species and brain region as the factors most strongly associated with gene expression in our samples. Next, we found gene categories related to cell structure, translation, and metabolism that differed in expression across species in virgins, as well as categories associated with cell structure, synaptic and neuroendocrine signaling, and transcription and translation that varied among the focal regions in our study. Additionally, we identified genes that were differentially expressed across species after mating in each of our regions of interest. These include genes involved in regulating transcription, neuron structure, and synaptic plasticity. Finally, we identified modules of co-regulated genes that were strongly correlated with brain region in both species, and modules that were correlated with post-mating time points in prairie voles but not meadow voles. Conclusions These results reinforce the importance of pre-mating differences that confer the ability to form pair bonds in prairie voles but not promiscuous species such as meadow voles. Gene ontology analysis supports the hypothesis that pair-bond formation involves transcriptional regulation, and changes in neuronal structure. Together, our results expand knowledge of the genes involved in the pair bonding process and open new avenues of research in the molecular mechanisms of bond formation.

Screening of cervical cancer-related hub genes based on comprehensive bioinformatics analysis

2021 ◽  
pp. 1-13
Author(s):  
Simei Tu ◽  
Hao Zhang ◽  
Xiaocheng Yang ◽  
Wen Wen ◽  
Kangjing Song ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cervical Cancer ◽  
Molecular Mechanisms ◽  
Disease Free Survival ◽  
The Cancer Genome Atlas ◽  
Mrna Levels ◽  
Hub Genes ◽  
Normal Tissues ◽  
Significant Difference ◽  
Core Genes

BACKGROUND: Since the molecular mechanisms of cervical cancer (CC) have not been completely discovered, it is of great significance to identify the hub genes and pathways of this disease to reveal the molecular mechanisms of cervical cancer. OBJECTIVE: The study aimed to identify the biological functions and prognostic value of hub genes in cervical cancer. METHODS: The gene expression data of CC patients were downloaded from the Gene Expression Omnibus (GEO) database and The Cancer Genome Atlas (TCGA) database. The core genes were screened out by differential gene expression analysis and weighted gene co-expression network analysis (WGCNA). R software, the STRING online tool and Cytoscape software were used to screen out the hub genes. The GEPIA public database was used to further verify the expression levels of the hub genes in normal tissues and tumour tissues and determine the disease-free survival (DFS) rates of the hub genes. The protein expression of the survival-related hub genes was identified with the Human Protein Atlas (HPA) database. RESULTS: A total of 64 core genes were screened, and 10 genes, including RFC5, POLE3, RAD51, RMI1, PALB2, HDAC1, MCM4, ESR1, FOS and E2F1, were identified as hub genes. Compared with that in normal tissues, RFC5, POLE3, RAD51,RMI1, PALB2, MCM4 and E2F1 were all significantly upregulated in cervical cancer, ESR1 was significantly downregulated in cervical cancer, and high RFC5 expression in CC patients was significantly related to OS. In the DFS analysis, no significant difference was observed in the expression level of RFC5 in cervical cancer patients. Finally, RFC5 protein levels verified by the HPA database were consistently upregulated with mRNA levels in CC samples. CONCLUSIONS: RFC5 may play important roles in the occurrence and prognosis of CC. It could be further explored and validated as a potential predictor and therapeutic target for CC.

A calcineurin- and NFAT-dependent pathway regulates Myf5 gene expression in skeletal muscle reserve cells

2001 ◽  
Vol 114 (2) ◽  
pp. 303-310 ◽  
Author(s):  
B.B. Friday ◽  
G.K. Pavlath
Keyword(s):  
Gene Expression ◽  
Skeletal Muscle ◽  
Satellite Cell ◽  
Cell Activation ◽  
Molecular Mechanisms ◽  
Fiber Type ◽  
Calcium Ionophore ◽  
Cell Populations ◽  
Mrna Levels ◽  
Dependent Pathway

Myf5 is a member of the muscle regulatory factor family of transcription factors and plays an important role in the determination, development, and differentiation of skeletal muscle. However, factors that regulate the expression and activity of Myf5 itself are not well understood. Recently, a role for the calcium-dependent phosphatase calcineurin was suggested in three distinct pathways in skeletal muscle: differentiation, hypertrophy, and fiber-type determination. We propose that one downstream target of calcineurin and the calcineurin substrate NFAT in skeletal muscle is regulation of Myf5 gene expression. For these studies, we used myotube cultures that contain both multinucleated myotubes and quiescent, mononucleated cells termed ‘reserve’ cells, which share many characteristics with satellite cells. Treatment of such myotube cultures with the calcium ionophore ionomycin results in an approximately 4-fold increase in Myf5 mRNA levels, but similar effects are not observed in proliferating myoblast cultures indicating that Myf5 is regulated by different pathways in different cell populations. The increase in Myf5 mRNA levels in myotube cultures requires the activity of calcineurin and NFAT, and can be specifically enhanced by overexpressing the NFATc isoform. We used immunohistochemical analyses and fractionation of the cell populations to demonstrate that the calcium regulated expression of Myf5 occurs in the mononucleated reserve cells. We conclude that Myf5 gene expression is regulated by a calcineurin- and NFAT-dependent pathway in the reserve cell population of myotube cultures. These results may provide important insights into the molecular mechanisms responsible for satellite cell activation and/or the renewal of the satellite cell pool following activation and proliferation.

scholarly journals Adipose Tissue Expansion by Overfeeding Healthy Men Alters Iron Gene Expression

2018 ◽  
Vol 104 (3) ◽  
pp. 688-696 ◽  
Author(s):  
Berenice Segrestin ◽  
José Maria Moreno-Navarrete ◽  
Kevin Seyssel ◽  
Maud Alligier ◽  
Emmanuelle Meugnier ◽  
...  
Keyword(s):  
Gene Expression ◽  
Adipose Tissue ◽  
Serum Iron ◽  
Tissue Expansion ◽  
Lipid Storage ◽  
Mrna Levels ◽  
Intracellular Iron ◽  
Gene Encoding ◽  
Iron Storage ◽  
Healthy Men

Abstract Context Iron overload has been associated with greater adipose tissue (AT) depots. We retrospectively studied the potential interactions between iron and AT during an experimental overfeeding in participants without obesity. Methods Twenty-six participants (mean body mass index ± SD, 24.7 ± 3.1 kg/m2) underwent a 56-day overfeeding (+760 kcal/d). Serum iron biomarkers (ELISA), subcutaneous AT (SAT) gene expression, and abdominal AT distribution assessed by MRI were analyzed at the beginning and the end of the intervention. Results Before intervention: SAT mRNA expression of the iron transporter transferrin (Tf) was positively correlated with the expression of genes related to lipogenesis (lipin 1, ACSL1) and lipid storage (SCD). SAT expression of the ferritin light chain (FTL) gene, encoding ferritin (FT), an intracellular iron storage protein, was negatively correlated to SREBF1, a gene related to lipogenesis. Serum FT (mean, 92 ± 57 ng/mL) was negatively correlated with the expression of SAT genes linked to lipid storage (SCD, DGAT2) and to lipogenesis (SREBF1, ACSL1). After intervention: Overfeeding led to a 2.3 ± 1.3-kg weight gain. In parallel to increased expression of lipid storage–related genes (mitoNEET, SCD, DGAT2, SREBF1), SAT Tf, SLC40A1 (encoding ferroportin 1, a membrane iron export channel) and hephaestin mRNA levels increased, whereas SAT FTL mRNA decreased, suggesting increased AT iron requirement. Serum FT decreased to 67 ± 43 ng/mL. However, no significant associations between serum iron biomarkers and AT distribution or expansion were observed. Conclusion In healthy men, iron metabolism gene expression in SAT is associated with lipid storage and lipogenesis genes expression and is modulated during a 56-day overfeeding diet.

R432 – Gene Expression of the Remodeling Rat Vocal Fold Wound

2008 ◽  
Vol 139 (2_suppl) ◽  
pp. P189-P189
Author(s):  
Tsunehisa Ohno ◽  
Lesley C. French ◽  
Bernard Rousseau
Keyword(s):  
Gene Expression ◽  
Extracellular Matrix ◽  
Messenger Rna ◽  
Vocal Fold ◽  
Molecular Mechanisms ◽  
Type I ◽  
Post Injury ◽  
Time Points ◽  
Procollagen Type ◽  
Procollagen Type I

Problem The authors investigated the expression of key extracellular matrix genes after vocal fold wounding in a rat model to better understand the reparative mechanisms of tissue repair during the remodeling phase of vocal fold injury. Methods Bilateral vocal fold wounds were created in 30 rats. Injured vocal fold specimens were harvested 1, 3, 7, 14, 28, and 56 days after wounding. 5 unwounded rats were used to establish baseline for polymerase chain reaction (PCR). The authors used real-time PCR to quantify messenger RNA expression of procollagen type I, III, interleukin-1 beta (IL-1 beta), decorin, and hyaluronan synthase (HAS) −1, −2, and −3. Analysis of variance was used to detect main effects for gene expression. Post-hoc tests were used to make comparisons between time points. Results Procollagen type I expression was decreased from baseline on post-injury day 1, 28, and 56. Procollagen type III was decreased on post-injury day 1 and 56, and increased from baseline on post-injury day 14. IL-1 beta expression was increased from baseline on post-injury day 1, 3, and 7. Decorin expression was decreased from baseline on post-injury day 1, 3, 7, and 56. HAS-1 expression was decreased from baseline at all post-injury time points. HAS-2 expression was increased from baseline on post-injury day 3, and decreased from baseline on post-injury day 14, 28, and 56. HAS-3 expression was decreased from baseline on post-injury day 1, 28, and 56. Conclusion Findings provide temporal changes in the expression of key extracellular matrix genes during a remodeling phase of vocal fold injury in a rat wound model. Significance Vocal fold wound models provide a means for investigating tissue reparative processes and molecular mechanisms controlling synthesis and degradation of the vocal fold extracellular matrix. Support Vanderbilt University Medical Center.

scholarly journals STIM1 Deficiency Leads to Specific Down-Regulation of ITPR3 in SH-SY5Y Cells

2020 ◽  
Vol 21 (18) ◽  
pp. 6598
Author(s):  
Carlos Pascual-Caro ◽  
Yolanda Orantos-Aguilera ◽  
Irene Sanchez-Lopez ◽  
Jaime de Juan-Sanz ◽  
Jan B. Parys ◽  
...  
Keyword(s):  
Gene Expression ◽  
Molecular Mechanisms ◽  
Ectopic Expression ◽  
Neuronal Cell ◽  
Atp Synthesis ◽  
Transport Systems ◽  
Synthesis Rate ◽  
Physical Interaction ◽  
Excitable Cells ◽  
Protein Levels

STIM1 is an endoplasmic reticulum (ER) protein that modulates the activity of a number of Ca2+ transport systems. By direct physical interaction with ORAI1, a plasma membrane Ca2+ channel, STIM1 activates the ICRAC current, whereas the binding with the voltage-operated Ca2+ channel CaV1.2 inhibits the current through this latter channel. In this way, STIM1 is a key regulator of Ca2+ signaling in excitable and non-excitable cells, and altered STIM1 levels have been reported to underlie several pathologies, including immunodeficiency, neurodegenerative diseases, and cancer. In both sporadic and familial Alzheimer’s disease, a decrease of STIM1 protein levels accounts for the alteration of Ca2+ handling that compromises neuronal cell viability. Using SH-SY5Y cells edited by CRISPR/Cas9 to knockout STIM1 gene expression, this work evaluated the molecular mechanisms underlying the cell death triggered by the deficiency of STIM1, demonstrating that STIM1 is a positive regulator of ITPR3 gene expression. ITPR3 (or IP3R3) is a Ca2+ channel enriched at ER-mitochondria contact sites where it provides Ca2+ for transport into the mitochondria. Thus, STIM1 deficiency leads to a strong reduction of ITPR3 transcript and ITPR3 protein levels, a consequent decrease of the mitochondria free Ca2+ concentration ([Ca2+]mit), reduction of mitochondrial oxygen consumption rate, and decrease in ATP synthesis rate. All these values were normalized by ectopic expression of ITPR3 in STIM1-KO cells, providing strong evidence for a new mode of regulation of [Ca2+]mit mediated by the STIM1-ITPR3 axis.

Synergistic Up-Regulation of Heme Oxygenase-1 in Human Liver by Heme and siRNA to Bach1:Possible Therapeutic Implications.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1633-1633
Author(s):  
Tahereh Ghaziani ◽  
Ying Shan ◽  
Richard W. Lambrecht ◽  
Herbert L. Bonkovsky
Keyword(s):  
Gene Expression ◽  
Heme Oxygenase ◽  
Ischemia Reperfusion Injury ◽  
Tissue Injury ◽  
Ischemia Reperfusion ◽  
Negative Regulator ◽  
Heme Oxygenase 1 ◽  
Significant Finding ◽  
Mrna Levels ◽  
Protein Levels

Abstract Background: Heme oxygenase-1 (HO-1) is an antioxidant defense enzyme that converts toxic heme into antioxidants. HO-1 is strongly up-regulated by its physiologic substrate, heme, which is currently the treatment of choice for acute attacks of porphyria and which may have other therapeutic uses, as well (e.g., for cytoprotection or amelioration of ischemia/reperfusion injury by increasing supply of carbon monoxide, biliverdin, or bilirubin). Up-regulation of HO-1 expression has been associated with increased resistance to tissue injury. Bach1 is a bZip protein which forms heterodimers with small Maf proteins. HO-1 is expressed at higher levels in tissues of Bach1-deficient mice, indicating that Bach1 acts as a negative regulator of the mouse HO-1 gene. The molecular mechanism that confers repression of HO-1 by Bach1, and whether there are similar effects in human cells, has remained elusive. The aim of this study was to assess whether modulation of human hepatic Bach1 expression by siRNA technology influences HO-1 gene expression and whether such gene silencing would enhance the inducing effects of heme on HO-1. Methods: siRNAs targeted 4 different positions of human Bach1 mRNA were designed and synthesized. We transfected Bach1-siRNA (25–200 nM) into Huh-7 cells using Lipofectamine for 24–72 h, after which, cells were treated with or without heme. We quantified HO-1 and Bach1 mRNA and protein levels by quantitative RT-PCR and western blotting, respectively. Effects and specificity of Bach1-siRNA were analyzed and compared with those of non-Bach1 related siRNAs (non-specific control-duplex (NSCD) and LaminB2-siRNA). Results: Bach1-siRNAs (25–200 nM) transfected into Huh-7 cells for 24–72 h significantly reduced Bach1 mRNA and protein levels approximately 80%, compared with non siRNA treated cells. In contrast, transfection with same amounts of NSCD or LaminB2 siRNA did not reduce Bach1 mRNA or protein levels, confirming the specificity of Bach1-siRNA in Huh-7 cells. A significant finding of these studies was the 7-fold up-regulation of the HO-1 gene in Bach1-siRNA transfected cells, compared to cells without Bach1-siRNA or those transfected with NSCD or LaminB2. Bach1, NSCD, and LaminB2 siRNAs had no effect on HO-2 or 5-aminolevulinate synthase-1 mRNA levels (two genes that are not induced by heme). The effects of increasing concentrations of heme (up to 10 μM) in the presence or absence of Bach1-siRNA on the levels of HO-1 mRNA expression are shown in the Figure. For all of the heme concentrations tested, the levels of HO-1 mRNA were greater when Bach1 siRNA was present. Conclusions: Bach1 has a specific and selective effect to repress expression of human hepatic HO-1. Silencing of the Bach1 gene by siRNAs may be a useful method for up-regulating HO-1 gene expression. The combination of intravenous heme and Bach1 silencing may be useful for therapy of acute porphyrias in relapse or other conditions in which up-regulation of HO-1 may be beneficial. (Supported by grants from NIH [DK38825] and Ovation Pharmaceuticals, Inc.) Figure Figure

Upregulation of the Anti-Apoptotic Protein, Survivin, in Hematopoietic Cells in Sickle Cell Anemia and Effects of Hydroxyurea Therapy.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1532-1532
Author(s):  
Carolina Lanaro ◽  
Carla Fernanda Franco-Penteado ◽  
Mariana R. B. Mello ◽  
Kleber Yotsumoto Fertrin ◽  
Marcos André C Bezerra ◽  
...  
Keyword(s):  
Gene Expression ◽  
Protein Expression ◽  
Sickle Cell Anemia ◽  
Survivin Expression ◽  
Erythroid Differentiation ◽  
Mrna Levels ◽  
Gene Expressions ◽  
Protein Levels ◽  
Survivin Protein ◽  
Inflammatory State

Abstract Abstract 1532 Poster Board I-555 Survivin (BIRC5) is a member of the inhibitors of apoptosis family implicated in both prevention of cell death and control of mitosis. Although the actions of survivin in control of cancer cell division and apoptosis have been studied, its role in nonneoplastic diseases is not elucidated. Chronic inflammation is associated with STAT-3 upregulation, which can induce survivin production. Sickle cell anemia (SCA) has been characterized as a chronic inflammatory state and growing evidence indicates that inflammatory stress within the microvasculature may play a significant role in the vasoocclusion that is characteristic of SCA. Long-term treatment with hydroxyurea (HU) has been shown to reduce the production of inflammatory cytokines in SCA patients and leukocyte number. Since enhanced survivin expression has been reported in leukocytes under inflammatory conditions, and during hematopoietic cell survival and proliferation, the aim of this study was to investigate changes in survivin levels during erythroid differentiation, and determine expression in neutrophils (NS), mononuclear cells (MC) and red blood cell (RBC) in steady-state SCA patients (n≥10), SCA patients on HU therapy (n≥16), and healthy controls (HC, n≥5). Survivin and STAT-3 gene expression were determined by qRT-PCR analysis in primary human erythroblasts cultures for 7, 10 and 13 days and leukocytes separated from peripheral blood samples. Survivin protein expression was determined by flow cytometry with survivin-specific antibodies. Survivin gene expression was significantly increased during erythroid differentiation, but survivin mRNA levels showed similar patterns between SCA and HC (7d: 0.8±0.1 × 0.7±0.08; 10d: 1.7±0.3 × 1.6±0.2; 13d: 2.2± 0.27 × 1.8±0.19,U.A.,P>0.05,respectively). However, protein levels of survivin in mature RBC (glicophorin A +) was significantly higher in SCA patients compared to HC (41.90± 2.9 × 25.76±1.9, P=0.0006, respectively). BIRC-5 gene expression in MC was significantly higher in SCA patients compared to HC (0.9±0.1 × 0.5±0.2, P=0.04, respectively). Survivin protein levels in MC from SCA was significantly increased to compared to HC (51.7±3.2 × 39.7±1.7, MFI, P=0.01,respectively). Survivin protein levels are elevated in NS of SCA patients compared to HC (28.4±1.6 × 21.9±1.5, MFI, P=0.02,respectively). No significant alterations in the mRNA levels of the gene encoding STAT-3 were found during erythroid differentiation (7d: 1.1±0.04 × 1.1±0.08; 10d: 0.6±0.07 × 0.8±0.08; 13d: 0.6±0.07 × 0.9±0.1, P>0.05,respectively) or MC cells (1.2±0.1 × 1.1± 0.1, P>0.05,respectively) in SCA patients compared to HC. Patients on HU therapy demonstrated lower survivin MC gene expressions and protein levels compared to non-treated patients (0.6±0.3 × 0.9±0.1; 37.9±1.5 × 51.7±3.3, P=0.02; P<0.0001,respectively), but no difference was shown in STAT-3 gene expressions (1.1±0.04 × 1.2 ±0.1, respectively). Survivin protein levels were not significantly different in NS and RBC in patients on HU therapy compared to SCA (27.1±1.8 × 28.4± 1.6; 45.9± 3.2× 41.9± 2.9, MFI, P>0.05, respectively). Our data showed that survivin gene and protein expression are upregulated in MC in SCA patients, independently of STAT-3 expression. In addition, a high protein expression was observed in NS and RBC in these patients. HU therapy was associated with lower survivin expression in MC, but not NS and RBC, indicating that the beneficial effect that HU has on the inflammatory state, may participate in the reduced levels of survivin. In conclusion, the exact importance of survivin in SCA vasooclusion is not clear, but data indicates a high expression of this protein in leukocytes and RBC of SCA patients and may imply a role for this protein in leukocytosis and RBC proliferation in SCA. Disclosures No relevant conflicts of interest to declare.

Alk3, a BMP Type I Receptor Is Required for the Induction of Hepatic Hepcidin Gene Expression by Interleukin-6

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 686-686 ◽  
Author(s):  
Andrea U. Steinbicker ◽  
Claire Mayeur ◽  
Lisa K. Lohmeyer ◽  
Patricio Leyton ◽  
Sonya M. Kao ◽  
...  
Keyword(s):  
Gene Expression ◽  
General Hospital ◽  
Small Molecule ◽  
Iron Metabolism ◽  
Serum Iron ◽  
Small Molecule Inhibitors ◽  
Massachusetts General Hospital ◽  
Bmp Signaling ◽  
Type I ◽  
Hepcidin Gene

Abstract Abstract 686 Introduction: Anemia of chronic disease (ACD), the second most prevalent form of anemia, is commonly associated with chronic inflammatory, infectious, or neoplastic conditions. ACD is characterized by high hepcidin levels that decrease serum iron levels by inducing degradation of the iron exporter ferroportin. In contrast, a relative deficiency of hepcidin leads to ferroportin overexpression and iron overload. Hepcidin is transcriptionally regulated by interleukin-6 (IL-6) and bone morphogenic protein (BMP) signaling. Binding of BMP ligands to type II and type I BMP receptors induces the type II receptor to phosphorylate and activate one of four type I receptors. We sought to identify the type I BMP receptor that participates in the ability of IL-6 to induce hepatic hepcidin gene expression. Methods: The four type I BMP receptors are Alk1, Alk2, Alk3, and Alk6. Alk1 is predominantly expressed in the endothelium. Alk6 is expressed at low levels in murine liver. In contrast, Alk2 and Alk3 are abundantly expressed in hepatocytes. Global deficiency of Alk2 or Alk3 is embryonic lethal. To selectively delete Alk2 or Alk3 in hepatocytes, we studied mice homozygous for Alk2 or Alk3 sequences flanked by loxP sites (Alk2fl/fl and Alk3fl/fl, respectively) that also carried a transgene specifying Cre recombinase under the control of the albumin gene promoter (Alb-Cre). Eight- to 12-week-old male mice (Alk2fl/fl, Alk2fl/fl; Alb-Cre, Alk3fl/fl, Alk3fl/fl; Alb-Cre) on a standard, iron-replete diet were injected via the tail vein with an adenovirus specifying IL-6 (Ad.IL-6) or an adenovirus specifying green fluorescent protein (GFP; Ad.GFP), as a control (1010 particles per ml for both). Seventy-two hours later, mice were euthanized, and blood was obtained for measurement of serum iron levels and transferrin saturations. Livers were harvested, and RNA was extracted. Hepatic levels of mRNAs encoding Alk2, Alk3, hepcidin, heme oxygenase-1 (HO-1, a transcriptional target of IL-6), and Id-1 (a BMP gene target) were measured by qRT-PCR. Hepatic STAT3 phosphorylation (a marker of IL-6 receptor activation) was measured using immunoblot techniques. Results: Liver-specific deletion of Alk2 or Alk3 caused mild and severe iron overload, respectively. Injection of Ad.IL-6, but not Ad.GFP, decreased serum iron levels and transferrin saturations in Alk2fl/fl, Alk2fl/fl; Alb-Cre, and Alk3fl/fl mice. In contrast, infection of Alk3fl/fl; Alb-Cre mice with Ad.IL-6 did not alter serum iron levels and only modestly reduced transferrin saturations. Infection with Ad.IL-6 induced of hepatic hepcidin gene expression in Alk2fl/fl, Alk2fl/fl; Alb-Cre, and Alk3fl/fl mice. Hepatic hepcidin mRNA levels were markedly reduced in Ad.GFP-infected Alk3fl/fl; Alb-Cre mice, and infection with Ad.IL-6 failed to increase hepcidin mRNA levels in this genotype. Ad.IL-6 infection induced hepatic Id-1 mRNA levels in Alk2fl/fl, Alk2fl/fl; Alb-Cre, and Alk3fl/fl mice, but not in Alk3fl/fl; Alb-Cre mice. Infection with Ad.IL-6 induced hepatic STAT-3 phosphorylation and HO-1 gene expression in all 4 genotypes of mice. Conclusions: Taken together, these results demonstrate that the response to IL-6, as reflected by STAT-3 phosphorylation and induction of HO-1 gene expression, does not require Alk2 or Alk3. In contrast, BMP signaling, predominantly via Alk3, is essential for the induction of hepcidin gene expression by IL-6. These results suggest that selective inhibition of Alk3 may represent a novel therapeutic approach to the treatment of ACD. Disclosures: Peterson: Massachusetts General Hospital: Patents & Royalties, The Massachusetts General Hospital has filed patents related to the use of small molecule inhibitors of BMP signaling to modulate iron metabolism, and PBY, RTP and KDB may be eligible to receive royalties. Yu:Massachusetts General Hospital: Patents & Royalties, The Massachusetts General Hospital has filed patents related to the use of small molecule inhibitors of BMP signaling to modulate iron metabolism, and PBY, RTP and KDB may be eligible to receive royalties. Bloch:Massachusetts General Hospital: Patents & Royalties, The Massachusetts General Hospital has filed patents related to the use of small molecule inhibitors of BMP signaling to modulate iron metabolism, and PBY, RTP and KDB may be eligible to receive royalties.

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