scholarly journals Plasma Kallikrein as a Modulator of Liver Injury/Remodeling

2021 ◽  
Vol 12 ◽  
Author(s):  
Ibrahim A Ahmed ◽  
Miran A Jaffa ◽  
Mayssam Moussa ◽  
Duaa Hatem ◽  
Ghewa A El-Achkar ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Death ◽  
Liver Injury ◽  
Cell Injury ◽  
Tissue Injury ◽  
Interleukin 1 ◽  
Temporal Variations ◽  
Plasma Kallikrein ◽  
Mrna Levels ◽  
Kinin System

The occurrence and persistence of hepatic injury which arises from cell death and inflammation result in liver disease. The processes that lead to liver injury progression and resolution are still not fully delineated. The plasma kallikrein-kinin system (PKKS) has been shown to play diverse functions in coagulation, tissue injury, and inflammation, but its role in liver injury has not been defined yet. In this study, we have characterized the role of the PKKS at various stages of liver injury in mice, as well as the direct effects of plasma kallikrein on human hepatocellular carcinoma cell line (HepG2). Histological, immunohistochemical, and gene expression analyses were utilized to assess cell injury on inflammatory and fibrotic factors. Acute liver injury triggered by carbon tetrachloride (CCl4) injection resulted in significant upregulation of the plasma kallikrein gene (Klkb1) and was highly associated with the high mobility group box 1 gene, the marker of cell death (r = 0.75, p < 0.0005, n = 7). In addition, increased protein expression of plasma kallikrein was observed as clusters around necrotic areas. Plasma kallikrein treatment significantly increased the proliferation of CCl4-induced HepG2 cells and induced a significant increase in the gene expression of the thrombin receptor (protease activated receptor-1), interleukin 1 beta, and lectin–galactose binding soluble 3 (galectin-3) (p < 0.05, n = 4). Temporal variations in the stages of liver fibrosis were associated with an increase in the mRNA levels of bradykinin receptors: beta 1 and 2 genes (p < 0.05; n = 3–10). In conclusion, these findings indicate that plasma kallikrein may play diverse roles in liver injury, inflammation, and fibrosis, and suggest that plasma kallikrein may be a target for intervention in the states of liver injury.

Neutrophil-induced liver cell injury in endotoxin shock is a CD11b/CD18-dependent mechanism

1991 ◽  
Vol 261 (6) ◽  
pp. G1051-G1056 ◽  
Author(s):  
H. Jaeschke ◽  
A. Farhood ◽  
C. W. Smith
Keyword(s):  
Liver Injury ◽  
Cell Injury ◽  
Tissue Injury ◽  
Oxidant Stress ◽  
Parenchymal Cell ◽  
Endotoxin Shock ◽  
Liver Cell Injury ◽  
Integrin Family ◽  
Dependent Mechanism

To investigate the role of neutrophils (PMNs) and PMN-dependent adhesion molecules in the pathogenesis of liver injury in a model of endotoxin shock, male ICR mice received a dose of 700 mg/kg galactosamine and 100 micrograms/kg Salmonella abortus equi endotoxin. PMNs accumulated continuously in the liver, reaching values of 446 +/- 71 PMNs/50 high-power fields at 9 h (basal value 18 +/- 7). Plasma alanine aminotransferase activities as index of parenchymal cell injury did not change up to 5 h posttreatment (basal value 35 +/- 5 U/l) but increased to 1,950 +/- 460 U/l at 9 h. The formation of glutathione disulfide (GSSG) in plasma as an index of an extracellular oxidant stress also increased only at 9 h. Pretreatment of animals with monoclonal antibodies against the CD11b and CD18 subunits of the CD11/CD18 integrin family on the surface of the PMN reduced the number of PMNs in the liver by 50% and significantly attenuated liver injury and GSSG formation. An anti-CD11a and a nonbinding control antibody were ineffective. It is concluded that PMNs are actively involved in the pathogenesis of galactosamine and endotoxin shock and that at least in part the accumulation of PMNs, the subsequent oxidant stress, and the tissue injury in this model of experimental hepatitis are CD11b/CD18 (Mac-1) dependent.

scholarly journals Nitric oxide modulation of human leukemia cell differentiation and gene expression

Blood ◽  
1992 ◽  
Vol 80 (8) ◽  
pp. 1880-1884 ◽  
Author(s):  
G Magrinat ◽  
SN Mason ◽  
PJ Shami ◽  
JB Weinberg
Keyword(s):  
Gene Expression ◽  
Nitric Oxide ◽  
Messenger Rna ◽  
Interleukin 1 ◽  
Leukemia Cell ◽  
Leukemia Cell Line ◽  
Tnf Alpha ◽  
Nonspecific Esterase ◽  
Human Leukemia ◽  
Mrna Levels

Abstract Nitric oxide (NO) functions as an intercellular messenger molecule in such varied contexts as neurotransmission, immune regulation, and the control of vascular tone. We report that NO, delivered as purified gas or released from the pharmacologic NO donors sodium nitroprusside or 6- morpholino-sydnonimine, caused monocytic differentiation of cells of the human myeloid leukemia cell line HL-60 and altered gene expression. The treated cells stopped proliferating, became spread and vacuolated, had increased expression of nonspecific esterase and the monocyte marker CD14, and displayed increased capacity to produce hydrogen peroxide. Furthermore, these treated cells had increased steady-state expression of messenger RNA (mRNA) for tumor necrosis factor-alpha (TNF- alpha) and interleukin-1 beta (IL-1 beta), but decreased expression of mRNA for the proto-oncogenes c-myc and c-myb. The increase in TNF-alpha and IL-1 beta mRNA levels was due (at least in part) to a new transcription of these specific mRNAs. NO elaborated in the bone marrow microenvironment may have a role in normal and malignant hematopoietic cell growth and differentiation.

scholarly journals Expression of Inflammation-Related Genes Is Altered in Gastric Tissue of Patients with Advanced Stages of NAFLD

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Rohini Mehta ◽  
Aybike Birerdinc ◽  
Arpan Neupane ◽  
Amirhossein Shamsaddini ◽  
Arian Afendy ◽  
...  
Keyword(s):  
Gene Expression ◽  
Hepatic Fibrosis ◽  
Interleukin 1 ◽  
Expression Patterns ◽  
Interleukin 8 ◽  
Morbidly Obese ◽  
Low Grade ◽  
Mrna Levels ◽  
Gastric Tissue ◽  
Hepatic Inflammation

Obesity is associated with chronic low-grade inflammation perpetuated by visceral adipose. Other organs, particularly stomach and intestine, may also overproduce proinflammatory molecules. We examined the gene expression patterns in gastric tissue of morbidly obese patients with nonalcoholic fatty liver disease (NAFLD) and compared the changes in gene expression in different histological forms of NAFLD. Stomach tissue samples from 20 morbidly obese NAFLD patients who were undergoing sleeve gastrectomy were profiled using qPCR for 84 genes encoding inflammatory cytokines, chemokines, their receptors, and other components of inflammatory cascades. Interleukin 8 receptor-beta (IL8RB) gene overexpression in gastric tissue was correlated with the presence of hepatic steatosis, hepatic fibrosis, and histologic diagnosis of nonalcoholic steatohepatitis (NASH). Expression levels of soluble interleukin 1 receptor antagonist (IL1RN) were correlated with the presence of NASH and hepatic fibrosis. mRNA levels of interleukin 8 (IL8), chemokine (C-C motif) ligand 4 (CCL4), and its receptor chemokine (C-C motif) receptor type 5 (CCR5) showed a significant increase in patients with advanced hepatic inflammation and were correlated with the severity of the hepatic inflammation. The results of our study suggest that changes in expression patterns for inflammatory molecule encoding genes within gastric tissue may contribute to the pathogenesis of obesity-related NAFLD.

scholarly journals Aryl Hydrocarbon Receptor Activation by TCDD Modulates Expression of Extracellular Matrix Remodeling Genes during Experimental Liver Fibrosis

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Cheri L. Lamb ◽  
Giovan N. Cholico ◽  
Daniel E. Perkins ◽  
Michael T. Fewkes ◽  
Julia Thom Oxford ◽  
...  
Keyword(s):  
Gene Expression ◽  
Extracellular Matrix ◽  
Liver Injury ◽  
Aryl Hydrocarbon Receptor ◽  
Receptor Activation ◽  
Matrix Remodeling ◽  
Mrna Levels ◽  
Gelatinase Activity ◽  
Ecm Remodeling ◽  
Aryl Hydrocarbon

The aryl hydrocarbon receptor (AhR) is a soluble, ligand-activated transcription factor that mediates the toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Increasing evidence implicates the AhR in regulating extracellular matrix (ECM) homeostasis. We recently reported that TCDD increased necroinflammation and myofibroblast activation during liver injury elicited by carbon tetrachloride (CCl4). However, TCDD did not increase collagen deposition or exacerbate fibrosis in CCl4-treated mice, which raises the possibility that TCDD may enhance ECM turnover. The goal of this study was to determine how TCDD impacts ECM remodeling gene expression in the liver. Male C57BL/6 mice were treated for 8 weeks with 0.5 mL/kg CCl4, and TCDD (20 μg/kg) was administered during the last two weeks. Results indicate that TCDD increased mRNA levels of procollagen types I, III, IV, and VI and the collagen processing molecules HSP47 and lysyl oxidase. TCDD also increased gelatinase activity and mRNA levels of matrix metalloproteinase- (MMP-) 3, MMP-8, MMP-9, and MMP-13. Furthermore, TCDD modulated expression of genes in the plasminogen activator/plasmin system, which regulates MMP activation, and it also increased TIMP1 gene expression. These findings support the notion that AhR activation by TCDD dysregulates ECM remodeling gene expression and may facilitate ECM metabolism despite increased liver injury.

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

scholarly journals Changes in gene expression induced by Micro-Immunotherapy

2021 ◽  
Vol 11 (40) ◽  
pp. 154-155
Author(s):  
Capieaux Etienne ◽  
Donat De Groote ◽  
Pierre Dorfman ◽  
Maurice Jeaner
Keyword(s):  
Gene Expression ◽  
Growth Factor ◽  
Dna Microarray ◽  
Interleukin 1 ◽  
Interleukin 2 ◽  
Diabetic Patients ◽  
Mrna Levels ◽  
Microarray Technology ◽  
Increased Risk ◽  
The Impact

Background: Metabolic syndrome (MS) is a metabolic disorder associated with obesity, type-II diabetes, and “low grade inflammation”, with the concomitant increased risk of cardiovascular events. As a chronic inflammatory process, MS results in a dysregulation of the cytokine profile. 2L®INFLAM, a Micro-immunotherapy (MI) medication formulated with highly diluted cytokines, is currently prescribed in Belgium for inflammatory diseases and potentially may be helpful for MS patients. Aims: To investigate the impact of 2L®INFLAM on selected gene expression markers (mRNA) in patients suffering from MS, in addition to biological and clinical parameters. Methodology: Four well characterized MS adult patients with stabilized body-weight were advised to take one capsule of 2L®INFLAM per day (by sublingual-oral route) for 6 months (composition in table 1). Concomitantly to biological and clinical examination, genes expression status was assessed by a DNA microarray technology (Oxygen™) comprising 200 genes involved mainly in oxidative stress and inflammation. Whole blood collection was performed before and after treatment (3-6 months) and mRNA levels measured. Gene expression was classified in 3 series (normally expressed, up or down-regulated) and genes related to diabetes predisposition were scored by using a proprietary Diascore (Probiox). Results: Before MI medication, a significant percentage of dysregulated genes (median: 16.3%) as well as a positive Diascore (median: 1.6) were noticed. Impressive correction of dysregulated genes (reaching 90% for one patient) was observed after 3 months of treatment (median: 2.3%) in addition to an improvement of Diascore in 3 MS patients out of 4 (median: 0.5). During the same period, both clinical and biological parameters remained unchanged. Conclusions: MS patients showing a high level of gene dysregulation efficiently normalized after 3 months of 2L®INFLAM (64%-90%), suggesting a biological regulatory effect of MI and a potential benefit of this medication for diabetic patients. Up and down-deregulated gene profiles were specific for each patient and not related to cytokine components of the formula. These preliminary data support the “domino effect” of MI sequential formula to restore in depth the immune homeostasis. DNA microarray technology may represent a promising tool for new provings as well as for biochemical comprehension of the “in vivo” effectiveness of highly diluted immune messengers. Table 1: 2L®INFLAM composition Compounds Dilutions Interleukin-1 (IL-1): 17 CH* Interleukin-1 Ra (IL-1 Ra): 3 CH Interleukin-2 (IL-2): 9 CH Interleukin-4 (IL-4): 7 CH Interleukin-6 (IL-6): 9 CH Interleukin-8 (IL-8): 9 CH Interleukin-10 (IL-10): 4 CH Interleukin-13 (IL-13): 9 CH Ciliary Neuro Trophic Factor (CNTF): 17 CH Leukemia Inhibitory Factor (LIF): 17 CH Oncostatine M (OSM): 9 CH Platelet Derived Growth Factor (PDGF): 5 CH Prostaglandine E2 (PgE2): 200 K** Rantes (Rantes): 17 CH Transforming Growth Factor beta(TGFβ): 5 CH Tumor Necrosis Factor α (TNFα): 17 CH SNA INFLAMa-01 18 C SNA INFLAMb-01 18 CH * CH: Centesimal Hahnemannian (1/100) ** K: Centesimal Korsakovian (1/100)

Control of the expression of inflammatory response genes

2003 ◽  
Vol 70 ◽  
pp. 95-106 ◽  
Author(s):  
Jeremy Saklatvala ◽  
Jonathan Dean ◽  
Andrew Clark
Keyword(s):  
Gene Expression ◽  
Transcription Factors ◽  
Inflammatory Response ◽  
Mapk Pathway ◽  
Interleukin 1 ◽  
Mitogen Activated Protein Kinase ◽  
Mrna Levels ◽  
Matrix Metalloproteinase 1 ◽  
Inflammatory Stimuli ◽  
Mitogen Activated Protein

The expression of genes involved in the inflammatory response is controlled both transcriptionally and post-transcriptionally. Primary inflammatory stimuli, such as microbial products and the cytokines interleukin-1 (IL-1) and tumour necrosis factor α (TNFα), act through receptors of either the Toll and IL-1 receptor (TIR) family or the TNF receptor family. These cause changes in gene expression by activating four major intracellular signalling pathways that are cascades of protein kinases: namely the three mitogen-activated protein kinase (MAPK) pathways, and the pathway leading to activation of the transcription factor nuclear factor ϰB (NFϰB). The pathways directly activate and induce the expression of a limited set of transcription factors which promote the transcription of inflammatory response genes. Many of the mRNAs are unstable, and are stabilized by the p38 MAPK pathway. Instability is mediated by clusters of the AUUUA motif in the 3″ untranslated regions of the mRNAs. Control of mRNA stability provides a means of increasing the amplitude of a response and allows rapid adjustment of mRNA levels. Not all mRNAs stabilized by p38 contain AUUUA clusters; for example, matrix metalloproteinase-1 and -3 mRNAs lack these clusters, but are stabilized. Inflammatory gene expression is inhibited by glucocorticoids. These suppress MAPK signalling by inducing a MAPK phosphatase. This may be a significant mechanism additional to that by which the glucocorticoid receptor interferes with transcription factors.

scholarly journals Downregulated KLF2 in PV and ET May Induce Prothrombotic Gene Expression

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 13-14
Author(s):  
Jihyun Song ◽  
Jahnavi Gollamudi ◽  
Soo Jin Kim ◽  
Radhika Gangaraju ◽  
Tsewang Tashi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Tissue Factor ◽  
Research Funding ◽  
Interleukin 1 ◽  
Negative Regulator ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Inherited Disorders ◽  
History Of

Polycythemia vera (PV) and essential thrombocythemia (ET) patients have a higher risk of arterial and venous thrombosis than healthy individuals; thromboses are their principal cause of morbidity and mortality. We reported increased transcription of prothrombotic and inflammatory genes in granulocytes and platelets of PV and ET. There were differences in the expression of prothrombotic genes between platelets and granulocytes, suggesting that these cells have cell-specific contributions to thrombosis in PV and ET. Some of these prothrombotic genes are regulated by hypoxia inducible factors (HIFs) (PMID: 32203583). However, the molecular mechanism of thrombosis in PV and ET remains unknown. KLF2 (Kruppel like factor 2) is a transcription factor regulating primitive erythropoiesis and inflammation. Knockdown of KLF2 in cultured endothelial cells increases prothrombotic gene expression and reduces blood clotting time and flow rates (PMID: 15718498). Targeted deletion of KLF2 in neutrophils increases thrombosis by inducing the expression and activity of tissue factor (Blood, 2018, 132:75). To study the role of KLF2 in PV and ET thrombosis, we measured KLF2 mRNA in granulocytes from 53 PV and ET patients (25 with a history of thrombosis) and in platelets from 40 patients (21 with a history of thrombosis). We also measured KLF2 mRNA in granulocytes from 38 controls and platelets from 18 controls. Althrough the role of KLF2 in thrombosis has been studied in neutrophils, we also tested KLF2 mRNA in platelets since we previously observed a different pattern of expression of prothrombotic genes between granulocytes and platelets in PV and ET. We found lower KLF2 mRNA in both granulocytes and platelets of PV and ET patients compared to the controls (Fig. 1A and B). Compared to patients without thrombosis, those with thrombosis had lower KLF2 mRNA in platelets but not granulocytes. KLF2 mRNA in these cells correlated inversely with JAK2V617F allele burden in granulocytes (Fig. 1C and D). We then measured mRNA of prothrombotic genes: F3 (tissue factor), SELP (P-selectin), IRAK1 (interleukin 1 receptor associated kinase 1), IL1RAP (interleukin 1 receptor accessory protein), VEGFA (vascular endothelial growth factor-A), THSB1 (thrombospondin 1), SERPINE1 (encoding plasminogen activator inhibitor 1 [PAI-1]). The mRNA levels of these prothrombotic genes correlated inversely with KLF2 mRNA in platelets while SELP and THSB1 transcripts correlated inversely with KLF2 mRNA in granulocytes. KLF2 and HIFs are reported to interact (PMID: 19491109, PMID: 21565532). In order to elucidate the regulatory machanism of KLF2 in thrombosis, we measured KLF2 mRNA in patients with two inherited disorders of hypoxia sensing characterized by thrombosis: 1) Chuvash erythrocytosis (CE) due to homozygous mutation of VHLR200W (13 patients) and 2) erythrocytosis due to gain-of-function mutation of HIF-2a (two patients with HIF2AM535V and two patients HIF2AE548K). KLF2 mRNA levels did not differ in granulocytes and platelets between these patients and controls. However, two CE patients and two patients with HIF2AM535V with a history of thrombosis had lower KLF2 mRNA levels compared to patients without thrombosis (ASH this meeting, 2020 Song J). In conclusion, we report here that KLF2 transcripts are down regulated in both granulocytes and platelets from PV and ET patients and they correlate inversely with the transcripts of prothrombotic genes and JAK2V617F allelic burden, suggesting that KLF2 might be a negative regulator of thrombotic gene expression in PV and ET. Here we did not detect any changes of KLF2 transcripts in congential disorders with elevated HIFs. However, two CE patients and 2 patients with HIF2AM535V with thrombosis had less KLF2 expression compared to those without thrombosis. These results suggest that, by inference from findings in congenital disorders with elevated HIFs, KLF2 in PV and ET granulocytes and platelets may be regulated in a HIF-independent manner but that thrombosis may be regulated in a HIF-dependent manner. Thus, KLF2 may be a novel therapeutic target to prevent thrombosis in PV and ET, but confirmation by further studies is needed. The upstream regulation of KLF2 in PV and ET granulocytes and platelets needs to be elucidated. *PT &JTP contributed equally Disclosures Gangaraju: Sanofi Genzyme, Consultant for Cold Agglutinin Disease: Consultancy. Gordeuk:CSL Behring: Consultancy, Research Funding; Global Blood Therapeutics: Consultancy, Research Funding; Imara: Research Funding; Ironwood: Research Funding; Novartis: Consultancy.

scholarly journals Nitric oxide modulation of human leukemia cell differentiation and gene expression

Blood ◽  
1992 ◽  
Vol 80 (8) ◽  
pp. 1880-1884 ◽  
Author(s):  
G Magrinat ◽  
SN Mason ◽  
PJ Shami ◽  
JB Weinberg
Keyword(s):  
Gene Expression ◽  
Nitric Oxide ◽  
Messenger Rna ◽  
Interleukin 1 ◽  
Leukemia Cell ◽  
Leukemia Cell Line ◽  
Tnf Alpha ◽  
Nonspecific Esterase ◽  
Human Leukemia ◽  
Mrna Levels

Nitric oxide (NO) functions as an intercellular messenger molecule in such varied contexts as neurotransmission, immune regulation, and the control of vascular tone. We report that NO, delivered as purified gas or released from the pharmacologic NO donors sodium nitroprusside or 6- morpholino-sydnonimine, caused monocytic differentiation of cells of the human myeloid leukemia cell line HL-60 and altered gene expression. The treated cells stopped proliferating, became spread and vacuolated, had increased expression of nonspecific esterase and the monocyte marker CD14, and displayed increased capacity to produce hydrogen peroxide. Furthermore, these treated cells had increased steady-state expression of messenger RNA (mRNA) for tumor necrosis factor-alpha (TNF- alpha) and interleukin-1 beta (IL-1 beta), but decreased expression of mRNA for the proto-oncogenes c-myc and c-myb. The increase in TNF-alpha and IL-1 beta mRNA levels was due (at least in part) to a new transcription of these specific mRNAs. NO elaborated in the bone marrow microenvironment may have a role in normal and malignant hematopoietic cell growth and differentiation.

Generation and functional significance of CXC chemokines for neutrophil-induced liver injury during endotoxemia

2005 ◽  
Vol 288 (5) ◽  
pp. G880-G886 ◽  
Author(s):  
Robert B. Dorman ◽  
Jaspreet S. Gujral ◽  
Mary Lynn Bajt ◽  
Anwar Farhood ◽  
Hartmut Jaeschke
Keyword(s):  
Liver Injury ◽  
Functional Significance ◽  
Cell Injury ◽  
Apoptotic Cell ◽  
Gene Knockout ◽  
Mrna Levels ◽  
Wild Type ◽  
Neutrophil Sequestration ◽  
Neutrophil Extravasation ◽  
Cxc Chemokine

Generation and functional significance of CXC chemokines for neutrophil-induced liver injury during endotoxemia. Am J Physiol Gastrointest Liver Physiol 288: G880–G886, 2005. First published December 2, 2004;.—The hypothesis that the neutrophil chemoattractant CXC chemokines KC and macrophage inflammatory protein-2 (MIP-2) are involved in neutrophil transmigration and liver injury was tested in C3Heb/FeJ mice treated with galactosamine (Gal, 700 mg/kg), endotoxin (ET, 100 μg/kg), or Gal + ET (Gal/ET). Hepatic KC and MIP-2 mRNA levels and plasma CXC chemokine concentrations were dramatically increased 1.5 h after Gal/ET or ET alone and gradually declined up to 7 h. Murine recombinant cytokines (TNF-α, IL-1α, and IL-1β), but not Gal/ET, induced CXC chemokine formation in the ET-resistant C3H/HeJ strain. To assess the functional importance of KC and MIP-2, C3Heb/FeJ mice were treated with Gal/ET and control IgG or a combination of anti-KC and anti-MIP-2 antibodies. Anti-CXC chemokine antibodies did not attenuate hepatocellular apoptosis, sinusoidal neutrophil sequestration and extravasation, or liver injury at 7 h. Furthermore, there was no difference in liver injury between BALB/cJ wild-type and CXC receptor-2 gene knockout (CXCR2−/−) mice treated with Gal/ET. The higher neutrophil count in livers of CXCR2−/−than in wild-type mice after Gal/ET was caused by the elevated number of neutrophils located in sinusoids of untreated CXCR2−/−animals. The pancaspase inhibitor Z-Val-Ala-Asp-fluoromethylketone eliminated Gal/ET-induced apoptosis and neutrophil extravasation and injury but not CXC chemokine formation. Thus Gal/ET induced massive, cytokine-dependent CXC chemokine formation in the liver. However, neutrophil extravasation and injury occurred in response to apoptotic cell injury at 6–7 h and was independent of CXC chemokine formation.

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