1
|
Li H, Yuan H, Yang ZP, Song Y, Wang JJ, Wen Q, Zheng YX, Zhang XX, Yu M, Yuan ZG. Differential transcriptome study on the damage of testicular tissues caused by chronic infection of T. gondii in mice. Parasit Vectors 2024; 17:252. [PMID: 38858789 PMCID: PMC11165745 DOI: 10.1186/s13071-024-06247-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 03/15/2024] [Indexed: 06/12/2024] Open
Abstract
BACKGROUND Toxoplasma gondii is an intracellular protozoan parasite that is widely distributed in humans and warm-blooded animals. T. gondii chronic infections can cause toxoplasmic encephalopathy, adverse pregnancy, and male reproductive disorders. In male reproduction, the main function of the testis is to provide a stable place for spermatogenesis and immunological protection. The disorders affecting testis tissue encompass abnormalities in the germ cell cycle, spermatogenic retardation, or complete cessation of sperm development. However, the mechanisms of interaction between T. gondii and the reproductive system is unclear. The aims were to study the expression levels of genes related to spermatogenesis, following T. gondii infection, in mouse testicular tissue. METHODS RNA-seq sequencing was carried out on mouse testicular tissues from mice infected or uninfected with the T. gondii type II Prugniaud (PRU) strain and validated in combination with real-time quantitative PCR and immunofluorescence assays. RESULTS The results showed that there were 250 significant differentially expressed genes (DEGs) (P < 0.05, |log2fold change| ≧ 1). Bioinformatics analysis showed that 101 DEGs were annotated to the 1696 gene ontology (GO) term. While there was a higher number of DEGs in the biological process classification as a whole, the GO enrichment revealed a significant presence of DEGs in the cellular component classification. The Arhgap18 and Syne1 genes undergo regulatory changes following T. gondii infection, and both were involved in shaping the cytoskeleton of the blood-testis barrier (BTB). The number of DEGs enriched in the MAPK signaling pathway, the ERK1/2 signaling pathway, and the JNK signaling pathway were significant. The PTGDS gene is located in the Arachidonic acid metabolism pathway, which plays an important role in the formation and maintenance of BTB in the testis. The expression of PTGDS is downregulated subsequent to T. gondii infection, potentially exerting deleterious effects on the integrity of the BTB and the spermatogenic microenvironment within the testes. CONCLUSIONS Overall, our research provides in-depth insights into how chronic T. gondii infection might affect testicular tissue and potentially impact male fertility. These findings offer a new perspective on the impact of T. gondii infection on the male reproductive system.
Collapse
Affiliation(s)
- Haoxin Li
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China
| | - Hao Yuan
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China.
| | - Zi-Peng Yang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China
| | - Yining Song
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China
| | - Jun-Jie Wang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China
| | - Qingyuan Wen
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China
| | - Yu-Xiang Zheng
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China.
| | - Xiu-Xiang Zhang
- College of Plant, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China.
| | - Miao Yu
- Key Laboratory of Oral Medicine, Guangzhou Institute of Oral Disease, Stomatology Hospital of Guangzhou Medical University, Guangzhou, 510140, People's Republic of China.
| | - Zi-Guo Yuan
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, People's Republic of China.
| |
Collapse
|
2
|
Deng BQ, Li MY, Fu X, Luo Y, Qiao Q, Liu JY. Targeted Metabolomics Study of Human Plasma Revealed Activation of the Cytochrome P450 Epoxygenase/Epoxide Hydrolase Axis in Patients with IgA Nephropathy. J Proteome Res 2022; 21:2969-2978. [PMID: 36301320 DOI: 10.1021/acs.jproteome.2c00471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
IgA nephropathy (IgAN) is the most common primary glomerulonephritis and a leading cause of chronic kidney disease. The pathogenic mechanism of IgAN remains largely unknown and thus a specific therapeutic target is lacking. Here, we reported that the cytochrome P450 (CYP) epoxygenase/epoxide hydrolase (EH) axis was activated in the patients and is likely a therapeutic target for IgAN. Specifically, quantitative profiling of the plasma from IgAN patients and healthy controls revealed significant changes in plasma levels of CYP/EH-mediated lipid epoxides and diols. Subsequently, CYP2C8, CYP2C18, CYP2J2, EPHX1, and EPHX2 were found to be significantly increased in whole blood cells at mRNA levels from the IgAN patients when compared with those of healthy controls. Immunohistochemical analysis showed that all five CYPs and two EHs were upregulated in the kidney tissue from IgAN patients when compared with normative renal tissue, but the expression locations of the proteins were different with most of them. Treatment of HK-2 cells with IgA1 increased cell viability, compressed cell apoptosis, and increased the protein levels of CYP2C9, EPHX1, and EPHX2. All the results agreed that CYPs/EHs axis is likely the prophylactic and therapeutic target for IgAN, providing IgAN patients with a new intervention strategy.
Collapse
Affiliation(s)
- Bing-Qing Deng
- Division of Nephrology, Dushu Lake Hospital Affiliated to Soochow University, Soochow 215135, China
| | - Meng-Yuan Li
- Department of Nephrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Xian Fu
- Center for Novel Target and Therapeutic Invention, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
| | - Ying Luo
- Department of Clinical Laboratory, Changning Maternity and Infant Health Hospital, East China Normal University, Shanghai 200050, China
| | - Qing Qiao
- Division of Nephrology, Dushu Lake Hospital Affiliated to Soochow University, Soochow 215135, China
| | - Jun-Yan Liu
- Center for Novel Target and Therapeutic Invention, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
| |
Collapse
|
3
|
Anti-inflammatory celastrol promotes a switch from leukotriene biosynthesis to formation of specialized pro-resolving lipid mediators. Pharmacol Res 2021; 167:105556. [PMID: 33812006 DOI: 10.1016/j.phrs.2021.105556] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/02/2021] [Accepted: 03/10/2021] [Indexed: 12/13/2022]
Abstract
The pentacyclic triterpenoid quinone methide celastrol (CS) from Tripterygium wilfordii Hook. F. effectively ameliorates inflammation with potential as therapeutics for inflammatory diseases. However, the molecular mechanisms underlying the anti-inflammatory and inflammation-resolving features of CS are incompletely understood. Here we demonstrate that CS potently inhibits the activity of human 5-lipoxygenase (5-LOX), the key enzyme in pro-inflammatory leukotriene (LT) formation, in cell-free assays with IC50 = 0.19-0.49 µM. Employing metabololipidomics using ultra-performance liquid chromatography coupled to tandem mass spectrometry in activated human polymorphonuclear leukocytes or M1 macrophages we found that CS (1 µM) potently suppresses 5-LOX-derived products without impairing the formation of lipid mediators (LM) formed by 12-/15-LOXs as well as fatty acid substrate release. Intriguingly, CS induced the generation of 12-/15-LOX-derived LM including the specialized pro-resolving mediator (SPM) resolvin D5 in human M2 macrophages. Finally, intraperitoneal pre-treatment of mice with 10 mg/kg CS strongly impaired zymosan-induced LT formation and simultaneously elevated the levels of SPM and related 12-/15-LOX-derived LM in peritoneal exudates, spleen and plasma in vivo. Conclusively, CS promotes a switch from LT biosynthesis to formation of SPM which may underlie the anti-inflammatory and inflammation-resolving effects of CS, representing an interesting pharmacological strategy for intervention with inflammatory disorders.
Collapse
|
4
|
Häfner AK, Kahnt AS, Steinhilber D. Beyond leukotriene formation—The noncanonical functions of 5-lipoxygenase. Prostaglandins Other Lipid Mediat 2019; 142:24-32. [DOI: 10.1016/j.prostaglandins.2019.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 03/14/2019] [Accepted: 03/25/2019] [Indexed: 01/17/2023]
|
5
|
Giménez-Bastida JA, Shibata T, Uchida K, Schneider C. Roles of 5-lipoxygenase and cyclooxygenase-2 in the biosynthesis of hemiketals E 2 and D 2 by activated human leukocytes. FASEB J 2017; 31:1867-1878. [PMID: 28096231 DOI: 10.1096/fj.201601136r] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 01/03/2017] [Indexed: 11/11/2022]
Abstract
The 2 hemiketal (HK) eicosanoids HKD2 and HKE2 are the major products of the biosynthetic crossover of the 5-lipoxygenase (5-LOX) and cyclooxygenase-2 (COX-2) pathways. HKs result from the rearrangement of a di-endoperoxide intermediate formed in the COX-2-dependent oxygenation of 5S-hydroxyeicosatetraenoic acid (5S-HETE). We analyzed HK biosynthesis in human leukocytes stimulated ex vivo and defined the biosynthetic roles of 5-LOX and COX-2, using inhibitors and incubations with exogenous substrates. Activation of leukocytes with LPS followed by treatment with the calcium ionophore A23187 resulted in the formation of PGE2, 5-HETE, and LTB4 as the principal metabolites of COX-2 and 5-LOX, respectively. The formation of HKD2 and HKE2 was highest after 15 min LPS treatment, and at that time, levels were similar to PGE2, but less than 5-HETE and LTB4 The time course of HK formation paralleled that of 5-HETE and LTB4, implying the availability of the 5S-HETE substrate as a limiting factor in biosynthesis rather than expression levels of COX-2. Specific inhibitors of COX-2 and 5-LOX decreased formation of HKD2 and HKE2 Platelets did not form HKs from exogenous 5S-HETE, implying that COX-1 is not involved. HKs are early products during an inflammatory event and require cells that express 5-LOX and COX-2 for their biosynthesis.-Giménez-Bastida, J. A., Shibata, T., Uchida, K., Schneider, C. Roles of 5-lipoxygenase and cyclooxygenase-2 in the biosynthesis of hemiketals E2 and D2 by activated human leukocytes.
Collapse
Affiliation(s)
- Juan A Giménez-Bastida
- Department of Pharmacology, Vanderbilt University Medical School, Nashville, Tennessee, USA.,Vanderbilt Institute of Chemical Biology, Vanderbilt University Medical School, Nashville, Tennessee, USA
| | - Takahiro Shibata
- Division of Biofunctional Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan; and
| | - Koji Uchida
- Division of Biofunctional Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan; and.,Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Claus Schneider
- Department of Pharmacology, Vanderbilt University Medical School, Nashville, Tennessee, USA; .,Vanderbilt Institute of Chemical Biology, Vanderbilt University Medical School, Nashville, Tennessee, USA
| |
Collapse
|
6
|
Häfner AK, Beilstein K, Graab P, Ball AK, Saul MJ, Hofmann B, Steinhilber D. Identification and Characterization of a New Protein Isoform of Human 5-Lipoxygenase. PLoS One 2016; 11:e0166591. [PMID: 27855198 PMCID: PMC5113960 DOI: 10.1371/journal.pone.0166591] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 10/31/2016] [Indexed: 11/18/2022] Open
Abstract
Leukotrienes (LTs) are inflammatory mediators that play a pivotal role in many diseases like asthma bronchiale, atherosclerosis and in various types of cancer. The key enzyme for generation of LTs is the 5-lipoxygenase (5-LO). Here, we present a novel putative protein isoform of human 5-LO that lacks exon 4, termed 5-LOΔ4, identified in cells of lymphoid origin, namely the Burkitt lymphoma cell lines Raji and BL41 as well as primary B and T cells. Deletion of exon 4 does not shift the reading frame and therefore the mRNA is not subjected to non-mediated mRNA decay (NMD). By eliminating exon 4, the amino acids Trp144 until Ala184 are omitted in the corresponding protein. Transfection of HEK293T cells with a 5-LOΔ4 expression plasmid led to expression of the corresponding protein which suggests that the 5-LOΔ4 isoform is a stable protein in eukaryotic cells. We were also able to obtain soluble protein after expression in E. coli and purification. The isoform itself lacks canonical enzymatic activity as it misses the non-heme iron but it still retains ATP-binding affinity. Differential scanning fluorimetric analysis shows two transitions, corresponding to the two domains of 5-LO. Whilst the catalytic domain of 5-LO WT is destabilized by calcium, addition of calcium has no influence on the catalytic domain of 5-LOΔ4. Furthermore, we investigated the influence of 5-LOΔ4 on the activity of 5-LO WT and proved that it stimulates 5-LO product formation at low protein concentrations. Therefore regulation of 5-LO by its isoform 5-LOΔ4 might represent a novel mechanism of controlling the biosynthesis of lipid mediators.
Collapse
Affiliation(s)
- Ann-Kathrin Häfner
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
- * E-mail: (DS); (A-KH)
| | - Kim Beilstein
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
| | - Philipp Graab
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
| | - Ann-Katrin Ball
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
| | - Meike J. Saul
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
- Department of Biology, Technical University of Darmstadt, 64287, Darmstadt, Germany
| | - Bettina Hofmann
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
| | - Dieter Steinhilber
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
- * E-mail: (DS); (A-KH)
| |
Collapse
|
7
|
Saccenti E, van Duynhoven J, Jacobs DM, Smilde AK, Hoefsloot HCJ. Strategies for individual phenotyping of linoleic and arachidonic acid metabolism using an oral glucose tolerance test. PLoS One 2015; 10:e0119856. [PMID: 25786212 PMCID: PMC4364740 DOI: 10.1371/journal.pone.0119856] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 01/16/2015] [Indexed: 12/04/2022] Open
Abstract
The ability to restore homeostasis upon environmental challenges has been proposed as a measure for health. Metabolic profiling of plasma samples during the challenge response phase should offer a profound view on the flexibility of a phenotype to cope with daily stressors. Current data modeling approaches, however, struggle to extract biological descriptors from time-resolved metabolite profiles that are able to discriminate between different phenotypes. Thus, for the case of oxylipin responses in plasma upon an oral glucose tolerance test we developed a modeling approach that incorporates a priori biological pathway knowledge. The degradation pathways of arachidonic and linoleic acids were modeled using a regression model based on a pseudo-steady-state approximated model, resulting in a parameter A that summarizes the relative enzymatic activity in these pathways. Analysis of the phenotypic parameters As suggests that different phenotypes can be discriminated according to preferred relative activity of the arachidonic and linoleic pathway. Correlation analysis shows that there is little or no competition between the arachidonic and linoleic acid pathways, although they share the same enzymes.
Collapse
Affiliation(s)
- Edoardo Saccenti
- Laboratory of Systems and Synthetic Biology, University of Wageningen and Research Center, Wageningen, The Netherlands
- Biosystem Data Analysis Group, University of Amsterdam, Amsterdam, The Netherlands
- Netherlands Metabolomics Centre, Leiden, The Netherlands
| | - John van Duynhoven
- Unilever Research & Development, Vlaardingen, The Netherlands
- Laboratory of Biophysics, University of Wageningen and Research Center, Wageningen, The Netherlands
- Netherlands Metabolomics Centre, Leiden, The Netherlands
| | - Doris M. Jacobs
- Unilever Research & Development, Vlaardingen, The Netherlands
- Netherlands Metabolomics Centre, Leiden, The Netherlands
| | - Age K. Smilde
- Biosystem Data Analysis Group, University of Amsterdam, Amsterdam, The Netherlands
- Netherlands Metabolomics Centre, Leiden, The Netherlands
| | - Huub C. J. Hoefsloot
- Biosystem Data Analysis Group, University of Amsterdam, Amsterdam, The Netherlands
- Netherlands Metabolomics Centre, Leiden, The Netherlands
| |
Collapse
|
8
|
Adel S, Kakularam KR, Horn T, Reddanna P, Kuhn H, Heydeck D. Leukotriene signaling in the extinct human subspecies Homo denisovan and Homo neanderthalensis. Structural and functional comparison with Homo sapiens. Arch Biochem Biophys 2014; 565:17-24. [PMID: 25447821 DOI: 10.1016/j.abb.2014.10.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 10/13/2014] [Accepted: 10/21/2014] [Indexed: 01/12/2023]
Abstract
Mammalian lipoxygenases (LOXs) have been implicated in cell differentiation and in the biosynthesis of pro- and anti-inflammatory lipid mediators. The initial draft sequence of the Homo neanderthalensis genome (coverage of 1.3-fold) suggested defective leukotriene signaling in this archaic human subspecies since expression of essential proteins appeared to be corrupted. Meanwhile high quality genomic sequence data became available for two extinct human subspecies (H. neanderthalensis, Homo denisovan) and completion of the human 1000 genome project provided a comprehensive database characterizing the genetic variability of the human genome. For this study we extracted the nucleotide sequences of selected eicosanoid relevant genes (ALOX5, ALOX15, ALOX12, ALOX15B, ALOX12B, ALOXE3, COX1, COX2, LTA4H, LTC4S, ALOX5AP, CYSLTR1, CYSLTR2, BLTR1, BLTR2) from the corresponding databases. Comparison of the deduced amino acid sequences in connection with site-directed mutagenesis studies and structural modeling suggested that the major enzymes and receptors of leukotriene signaling as well as the two cyclooxygenase isoforms were fully functional in these two extinct human subspecies.
Collapse
Affiliation(s)
- Susan Adel
- Institute of Biochemistry, Charite - University Medicine Berlin, Chariteplatz 1, 10117 Berlin, Germany
| | - Kumar Reddy Kakularam
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Andhra Pradesh, India
| | - Thomas Horn
- Institute of Biochemistry, Charite - University Medicine Berlin, Chariteplatz 1, 10117 Berlin, Germany
| | - Pallu Reddanna
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046, Andhra Pradesh, India; National Institute of Animal Biotechnology, Hyderabad 500046, Andhra Pradesh, India
| | - Hartmut Kuhn
- Institute of Biochemistry, Charite - University Medicine Berlin, Chariteplatz 1, 10117 Berlin, Germany.
| | - Dagmar Heydeck
- Institute of Biochemistry, Charite - University Medicine Berlin, Chariteplatz 1, 10117 Berlin, Germany
| |
Collapse
|
9
|
Experimental prestorage filtration removes antibodies and decreases lipids in RBC supernatants mitigating TRALI in vivo. Blood 2014; 123:3488-95. [PMID: 24747436 DOI: 10.1182/blood-2013-10-532424] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transfusion-related acute lung injury (TRALI) remains a significant cause of transfusion-related mortality with red cell transfusion. We hypothesize that prestorage filtration may reduce proinflammatory activity in the red blood cell (RBC) supernatant and prevent TRALI. Filters were manufactured for both small volumes and RBC units. Plasma containing antibodies to human lymphocyte antigen (HLA)-A2 or human neutrophil antigen (HNA)-3a was filtered, and immunoglobulins and specific HNA-3a and HLA-2a neutrophil (PMN) priming activity were measured. Antibodies to OX27 were added to plasma, and filtration was evaluated in a 2-event animal model of TRALI. RBC units from 31 donors known to have antibodies against HLA antigens and from 16 antibody-negative controls were filtered. Furthermore, 4 RBC units were drawn and underwent standard leukoreduction. Immunoglobulins, HLA antibodies, PMN priming activity, and the ability to induce TRALI in an animal model were measured. Small-volume filtration of plasma removed >96% of IgG, antibodies to HLA-A2 and HNA-3a, and their respective priming activity, as well as mitigating antibody-mediated in vivo TRALI. In RBC units, experimental filtration removed antibodies to HLA antigens and inhibited the accumulation of lipid priming activity and lipid-mediated TRALI. We conclude that filtration removes proinflammatory activity and the ability to induce TRALI from RBCs and may represent a TRALI mitigation step.
Collapse
|
10
|
Sindhu RK, Arora S. Therapeutic Effect of Ficus lacor Aerial Roots of Various Fractions on Adjuvant-Induced Arthritic Rats. ISRN PHARMACOLOGY 2013; 2013:634106. [PMID: 24167737 PMCID: PMC3791571 DOI: 10.1155/2013/634106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/19/2013] [Indexed: 06/02/2023]
Abstract
The present study was carried out to evaluate antiarthritic potential and phytochemical screening of various extracts of Ficus lacor aerial roots. The antiarthritic activity was evaluated by adjuvant-induced arthritis at the dose of 50 and 100 mg/kg body weight and the standard drug used was indomethacin. The extracts administered in higher doses reduced the lesions to a greater extent showing a dose-dependent decrease in lesions comparable with standard drug indomethacin. The extracts of FLPE and FLET showed significant increase in body weight as compared to arthritic control group as well as an increase in liver weight, a decrease in liver weight, and an increase in spleen weight in arthritis control. The extracts of FLPE and FLET showed significant decrease in WBC count, increase in hemoglobin contents, and RBC count as compared to control group. FLEA and FLCF were not able to produce a significant effect. There was significant reduction in production of IL-1 and TNF- α level between model group and control group in serum. In conclusion, we demonstrate that, at 100 mg/kg body weight, doses of FLPE and PLET extracts were highly effective in preventing and suppressing the development of adjuvant-induced arthritis.
Collapse
Affiliation(s)
- Rakesh K. Sindhu
- Chitkara College of Pharmacy, Chitkara University, Chandigarh-Patiala NH-64, Rajpura, Patiala 140401, Punjab, India
| | - Sandeep Arora
- Chitkara College of Pharmacy, Chitkara University, Chandigarh-Patiala NH-64, Rajpura, Patiala 140401, Punjab, India
| |
Collapse
|
11
|
Chaitidis P, Adel S, Anton M, Heydeck D, Kuhn H, Horn T. Lipoxygenase pathways in Homo neanderthalensis: functional comparison with Homo sapiens isoforms. J Lipid Res 2013; 54:1397-409. [PMID: 23475662 DOI: 10.1194/jlr.m035626] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lipoxygenases (LOX) have been implicated in biosynthesis of pro- and anti-inflammatory mediators, and a previous report suggested compromised leukotriene signaling in H. neanderthalensis. To search for corresponding differences in leukotriene biosynthesis, we screened the Neandertal genome for LOX genes and found that, as modern humans, this archaic hominid contains six LOX genes (nALOX15, nALOX12, nALOX5, nALOX15B, nALOX12B, and nALOXE3) and one pseudogene. In the Neandertal genome, 60-75% of the amino acids of the different human LOX isoforms have been identified, and the degree of identity varies between 96 and 99%. Most functional amino acids (iron ligands, specificity determinants, calcium and ATP-binding sites, membrane-binding determinants, and phosphorylation sites) are well conserved in the Neandertal LOX isoforms, and expression of selected neandertalized human LOX mutants revealed no major functional defects. However, in nALOX12 and nALOXE3, two premature stop codons were found, leading to inactive enzyme species. These data suggest that ALOX15, ALOX5, ALOX15B, and ALOX12B should have been present as functional enzymes in H. neanderthalensis and that in contrast to lower nonhuman primates (M. mulatta) and other mammals (mice, rats), this ancient hominid expressed a 15-lipoxygenating ALOX15. Expression of ALOXE3 and ALOX12 was compromised, which might have caused problems in epidermal differentiation.
Collapse
Affiliation(s)
- Pavlos Chaitidis
- Institute of Biochemistry, University Medicine Berlin - Charité, 10117 Berlin, Germany
| | | | | | | | | | | |
Collapse
|
12
|
Kummer NT, Nowicki TS, Azzi JP, Reyes I, Iacob C, Xie S, Swati I, Darzynkiewicz Z, Gotlinger KH, Suslina N, Schantz S, Tiwari RK, Geliebter J. Arachidonate 5 lipoxygenase expression in papillary thyroid carcinoma promotes invasion via MMP-9 induction. J Cell Biochem 2012; 113:1998-2008. [PMID: 22253131 DOI: 10.1002/jcb.24069] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Arachidonate 5-lipoxygenase (ALOX5) expression and activity has been implicated in tumor pathogenesis, yet its role in papillary thyroid carcinoma (PTC) has not been characterized. ALOX5 protein and mRNA were upregulated in PTC compared to matched, normal thyroid tissue, and ALOX5 expression correlated with invasive tumor histopathology. Evidence suggests that PTC invasion is mediated through the induction of matrix metalloproteinases (MMPs) that can degrade and remodel the extracellular matrix (ECM). A correlation between MMP-9 and ALOX5 protein expression was established by immunohistochemical analysis of PTC and normal thyroid tissues using a tissue array. Transfection of ALOX5 into a PTC cell line (BCPAP) increased MMP-9 secretion and cell invasion across an ECM barrier. The ALOX5 product, 5(S)-hydroxyeicosatetraenoic acid also increased MMP-9 protein expression by BCPAP in a dose-dependent manner. Inhibitors of MMP-9 and ALOX5 reversed ALOX5-enhanced invasion. Here we describe a new role for ALOX5 as a mediator of invasion via MMP-9 induction; this ALOX5/MMP9 pathway represents a new avenue in the search for functional biomarkers and/or potential therapeutic targets for aggressive PTC.
Collapse
Affiliation(s)
- Nicolas T Kummer
- Department of Microbiology & Immunology, New York Medical College, Valhalla, New York 10595, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Stephensen CB, Armstrong P, Newman JW, Pedersen TL, Legault J, Schuster GU, Kelley D, Vikman S, Hartiala J, Nassir R, Seldin MF, Allayee H. ALOX5 gene variants affect eicosanoid production and response to fish oil supplementation. J Lipid Res 2011; 52:991-1003. [PMID: 21296957 DOI: 10.1194/jlr.p012864] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The objective of this study was to determine whether 5-lipoxygenase (ALOX5) gene variants associated with cardiovascular disease affect eicosanoid production by monocytes. The study was a randomized, double-masked, parallel intervention trial with fish oil (5.0 g of fish oil daily, containing 2.0 g of eicosapentaenoic acid [EPA] and 1.0 g of docosahexaenoic acid [DHA]) or placebo oil (5.0 g of corn/soy mixture). A total of 116 subjects (68% female, 20-59 years old) of African American ancestry enrolled, and 98 subjects completed the study. Neither ALOX5 protein nor arachidonic acid-derived LTB4, LTD4, and LTE4 varied by genotype, but 5-hydroxyeicosatetraenoate (5-HETE), 6-trans-LTB4, 5-oxo-ETE, 15-HETE, and 5,15-diHETE levels were higher in subjects homozygous for the ALOX5 promoter allele containing five Sp1 element tandem repeats ("55" genotype) than in subjects with one deletion (d) (three or four repeats) and one common ("d5" genotype) allele or with two deletion ("dd") alleles. The EPA-derived metabolites 5-HEPE and 15-HEPE and the DHA-derived metabolite 17-HDoHE had similar associations with genotype and increased with supplementation; 5-HEPE and 15-HEPE increased, and 5-oxo-ETE decreased to a greater degree in the 55 than in the other genotypes. This differential eicosanoid response is consistent with the previously observed interaction of these variants with dietary intake of omega-3 fatty acids in predicting cardiovascular disease risk.
Collapse
Affiliation(s)
- Charles B Stephensen
- Western Human Nutrition Research Center, US Department of Agriculture, Davis, CA 95616, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Carmo ÉVDS, Katz S, Barbiéri CL. Neutrophils reduce the parasite burden in Leishmania (Leishmania) amazonensis-infected macrophages. PLoS One 2010; 5:e13815. [PMID: 21082032 PMCID: PMC2972777 DOI: 10.1371/journal.pone.0013815] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Accepted: 10/13/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Studies on the role of neutrophils in Leishmania infection were mainly performed with L. (L) major, whereas less information is available for L. (L) amazonensis. Previous results from our laboratory showed a large infiltrate of neutrophils in the site of infection in a mouse strain resistant to L. (L.) amazonensis (C3H/HePas). In contrast, the susceptible strain (BALB/c) displayed a predominance of macrophages harboring a high number of amastigotes and very few neutrophils. These findings led us to investigate the interaction of inflammatory neutrophils with L. (L.) amazonensis-infected macrophages in vitro. METHODOLOGY/PRINCIPAL FINDINGS Mouse peritoneal macrophages infected with L. (L.) amazonensis were co-cultured with inflammatory neutrophils, and after four days, the infection was quantified microscopically. Data are representative of three experiments with similar results. The main findings were 1) intracellular parasites were efficiently destroyed in the co-cultures; 2) the leishmanicidal effect was similar when cells were obtained from mouse strains resistant (C3H/HePas) or susceptible (BALB/c) to L. (L.) amazonensis; 3) parasite destruction did not require contact between infected macrophages and neutrophils; 4) tumor necrosis factor alpha (TNF-α), neutrophil elastase and platelet activating factor (PAF) were involved with the leishmanicidal activity, and 5) destruction of the parasites did not depend on generation of oxygen or nitrogen radicals, indicating that parasite clearance did not involve the classical pathway of macrophage activation by TNF-α, as reported for other Leishmania species. CONCLUSIONS/SIGNIFICANCE The present results provide evidence that neutrophils in concert with macrophages play a previously unrecognized leishmanicidal effect on L. (L.) amazonensis. We believe these findings may help to understand the mechanisms involved in innate immunity in cutaneous infection by this Leishmania species.
Collapse
Affiliation(s)
| | - Simone Katz
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brasil
| | - Clara Lúcia Barbiéri
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brasil
- * E-mail:
| |
Collapse
|
15
|
Akhtar Khan N. Polyunsaturated fatty acids in the modulation of T-cell signalling. Prostaglandins Leukot Essent Fatty Acids 2010; 82:179-87. [PMID: 20189788 DOI: 10.1016/j.plefa.2010.02.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Indexed: 11/25/2022]
Abstract
n-3 polyunsaturated fatty acids (PUFA) have been shown to modulate immune responses. These agents, being considered as adjuvant immunosuppressants, have been used in the treatment of various inflammatory and autoimmune diseases. However, the molecular mechanisms of action of n-3 PUFA-induced immunosuppressive effects are not well-understood. Since exogenous n-3 PUFA, under in vitro and in vivo conditions, are efficiently incorporated into T-cell plasma membranes, a number of recent studies have demonstrated that these agents may modulate T-cell signalling. In this review, the interactions of n-3 PUFA with the second messenger cascade initiated during early and late events of T-cell activation are discussed. We particularly focus on how these fatty acids can modulate the production of diacylglycerol and the activation of protein kinase C, mitogen activated protein kinase, calcium signalling and translocation of transcriptional factors, implicated in the regulation of gene transcription in T-cells.
Collapse
Affiliation(s)
- Naim Akhtar Khan
- University of Burgundy, Department of Physiology, UPRES EA4183 Lipids and Cell Signalling, Faculty of Life Sciences, Dijon, France.
| |
Collapse
|
16
|
Finkensieper A, Kieser S, Bekhite MM, Richter M, Mueller JP, Graebner R, Figulla HR, Sauer H, Wartenberg M. The 5-lipoxygenase pathway regulates vasculogenesis in differentiating mouse embryonic stem cells. Cardiovasc Res 2009; 86:37-44. [DOI: 10.1093/cvr/cvp385] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
|
17
|
Lehmann B, Hübner C, Jacobi H, Kämpf A, Wozel G. Effects of dietary γ-linolenic acid-enriched evening primrose seed oil on the 5-lipoxygenase pathway of neutrophil leukocytes in patients with atopic dermatitis. J DERMATOL TREAT 2009. [DOI: 10.3109/09546639509086846] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
18
|
Leukotriene B4 activates T cells that inhibit B-cell proliferation in EBV-infected cord blood–derived mononuclear cell cultures. Blood 2008; 111:2693-703. [DOI: 10.1182/blood-2007-08-102319] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Epstein-Barr virus (EBV)–specific cellular memory is not transferred from mother to child. Therefore, EBV-induced B-cell proliferation in in vitro–infected cord blood mononuclear cell cultures is not inhibited. However, by addition of immunomodulators, polysaccharide K (PSK) or truncated thioredoxin (Trx80) that activate monocytes, EBV-specific T-cell response could be generated in such cultures. Presently, we demonstrate that leukotriene B4 (LTB4) is involved in the effect of the immunomodulators. LTB4 was detected in the medium, and T-cell activation was compromised by addition of leukotriene biosynthesis inhibitors. Moreover, we found that LTB4 added to infected cultures, which did not receive the immunomodulators, induced functional activation of the T cells. LTB4 activated the monocytes and acted directly on the T cells. In consequence, addition of LTB4 inhibited the EBV-induced proliferation of B lymphocytes. Specific cytotoxicity could be generated by restimulation of the T cells. The experiments showed successive stages of T-cell activation in acquisition of their immunologic effector function. This is orchestrated by complex cellular interactions, and autocrine loops mediated by soluble factors—here interferon (IFN)-γ, interleukin (IL)-15, IL-12, and LTB4. Importantly, the results indicate that endogenous LTB4 can induce T-cell activation that inhibits the EBV-induced proliferation of B lymphocytes.
Collapse
|
19
|
Altmann R, Hausmann M, Spöttl T, Gruber M, Bull AW, Menzel K, Vogl D, Herfarth H, Schölmerich J, Falk W, Rogler G. 13-Oxo-ODE is an endogenous ligand for PPARgamma in human colonic epithelial cells. Biochem Pharmacol 2007; 74:612-22. [PMID: 17604003 DOI: 10.1016/j.bcp.2007.05.027] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Revised: 05/14/2007] [Accepted: 05/31/2007] [Indexed: 11/27/2022]
Abstract
BACKGROUND The ligand activated nuclear hormone receptor peroxisome proliferator-activated receptor gamma (PPARgamma) induces transcriptional repression of pro-inflammatory factors. Activation of PPARgamma is followed by amelioration of colitis in animal models of inflammatory bowel disease (IBD). A reduced expression of PPARgamma was found in epithelial cells of patients with ulcerative colitis. The eicosanoids 13-HODE and 15-HETE are products of 12/15-lipoxygenase (LOX) and endogenous ligands for PPARgamma. Dehydrogenation of 13-HODE by 13-HODE dehydrogenase results in formation of the 13-Oxo-ODE. Highest activity of 13-HODE dehydrogenase is found in colonic epithelial cells (CECs). We therefore investigated whether 13-Oxo-ODE is a new endogenous ligand of PPARgamma in CECs. METHODS LOX activity and 13-HODE dehydrogenase in CECs were investigated after stimulation with arachidonic or linoleic acid. LOX metabolites were identified by RP-18 reversed-phase HPLC. Binding of (14)C-labelled 13-Oxo-ODE was demonstrated using a His-tagged PPARgamma. RESULTS Stimulation of HT-29 and primary CECs homogenates with and without Ca-ionophor was followed by the formation of high amounts of the linoleic acid metabolite 13-Oxo-ODE (155 and 85 ng/ml). The decrease of IL-8 secretion from IEC was more pronounced after pre-incubation with 13-Oxo-ODE compared to the PPARgamma agonist troglitazone and higher as with the known PPARgamma ligands 13-HODE and 15-HETE. Binding assays with (14)C-labelled 13-Oxo-ODE clearly demonstrated a direct interaction. CONCLUSION High amounts of 13-Oxo-ODE can be induced in CECs by stimulation of linoleic acid metabolism. 13-Oxo-ODE binds to PPARgamma and has anti-inflammatory effects. 13-HODE dehydrogenase might be a therapeutic target in IBD.
Collapse
Affiliation(s)
- Reinhold Altmann
- Department of Internal Medicine I, University of Regensburg, 93042 Regensburg, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Cook-Moreau JM, El-Makhour Hojeij Y, Barrière G, Rabinovitch-Chable HC, Faucher KS, Sturtz FG, Rigaud MA. Expression of 5-lipoxygenase (5-LOX) in T lymphocytes. Immunology 2007; 122:157-66. [PMID: 17484769 PMCID: PMC2265994 DOI: 10.1111/j.1365-2567.2007.02621.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
5-Lipoxygenase (5-LOX) is the key enzyme responsible for the synthesis of the biologically active leukotrienes. Its presence has been reported in cells of the myeloid lineage and B lymphocytes but has not been formally defined in T lymphocytes. In this study, we provide evidence for 5-LOX expression on both transcriptional and translational levels in highly purified peripheral blood T cells as well as in human T lymphoblastoid cell lines (MOLT4 and Jurkat). Messenger RNA (mRNA) of 5-LOX was amplified by conventional reverse transcription-polymerase chain reaction (RT-PCR; MOLT4 and Jurkat cells) and by in situ RT-PCR (T lymphocytes). 5-LOX protein expression was confirmed by Western blot and immunofluorescence studies. 5-LOX was present primarily in the cytoplasm with some nuclear localization and was translocated to the nuclear periphery after culture in a mitosis-supporting medium. Fluorescence-activated cell sorter analysis of different T-lymphocyte populations, including CD4, CD8, CD45RO, CD45RA, T helper type 2, and T-cell receptor-alphabeta and -gammadelta expressing cells, did not identify a differential distribution of the enzyme. Purified peripheral blood T lymphocytes were incapable of synthesizing leukotrienes in the absence of exogenous arachidonic acid. Jurkat cells produced leukotriene C(4) and a small amount of leukotriene B(4) in response to CD3-CD28 cross-linking. This synthesis was abolished by two inhibitors of leukotriene synthesis, MK-886 and AA-861. The presence of 5-LOX in T lymphocytes but the absence of endogenous lipoxygenase metabolite production compared to Jurkat cells may constitute a fundamental difference between resting peripheral lymphocytes and leukaemic cells.
Collapse
Affiliation(s)
- Jeanne M Cook-Moreau
- Laboratoire de Biochimie et Génétique Moléculaire, Faculté de Médecine, Limoges, France.
| | | | | | | | | | | | | |
Collapse
|
21
|
Berger W, De Chandt MTM, Cairns CB. Zileuton: clinical implications of 5-Lipoxygenase inhibition in severe airway disease. Int J Clin Pract 2007; 61:663-76. [PMID: 17394438 DOI: 10.1111/j.1742-1241.2007.01320.x] [Citation(s) in RCA: 139] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The 5-Lipoxygenase pathway results in the formation of leukotrienes, including leukotriene B(4) (LTB(4)), 5-oxo-6E,8Z,11Z,14Z-eicosatetranoic acid and the cysteinyl leukotrienes (LTC(4), LTD(4) and LTE(4)) and activates all four leukotriene receptors, BLT1, BLT2, cysLT(1) and cysLT(2). Zileuton is the only commercially available inhibitor of the 5-Lipoxygenase pathway. In a number of clinical trials, zileuton has been shown to improve airway function and inflammation, asthma symptom control and quality of life in asthmatics. Given the important role that leukotrienes play in airway inflammation, zileuton provides an additional therapeutic option in the management of chronic, persistent asthma, particularly those asthmatics with more severe disease. In addition, zileuton has shown promise in a number of other conditions, including upper airway inflammatory conditions, dermatological disease and chronic obstructive pulmonary disease. The development of new formulations, including a controlled release tablet formulation for b.i.d. dosing and an intravenous preparation for acute asthma exacerbations may enhance clinical utility and expand therapeutic indications.
Collapse
Affiliation(s)
- W Berger
- Department of Pediatrics, Division of Allergy and Immunology, University of California, Irvine, Mission Viejo, CA, USA
| | | | | |
Collapse
|
22
|
O'Connor BJ, Löfdahl CG, Balter M, Szczeklik A, Boulet LP, Cairns CB. Zileuton added to low-dose inhaled beclomethasone for the treatment of moderate to severe persistent asthma. Respir Med 2007; 101:1088-96. [PMID: 17360171 DOI: 10.1016/j.rmed.2007.01.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2006] [Revised: 01/24/2007] [Accepted: 01/26/2007] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To assess the therapeutic effects of oral zileuton tablets combined with low-dose beclomethasone compared to doubling the dose of beclomethasone, in improving lung function and reducing asthma symptoms. METHODS Randomized, active-control, double-blind, parallel, multi-center study of zileuton (400 or 600 mg QID)+200 microg beclomethasone dipropionate (BDP) BID versus placebo+BDP 400 microg BID in asthmatics with baseline FEV(1) percent predicted values between 40% and 80% following a single-blind ICS (BDP 200 microg BID) 2-week run-in. During the 3-month double-blind treatment period, assessments included safety, daytime and nighttime symptoms, acute asthma exacerbations, beta(2)-agonist use, AM and PM peak expiratory flow (PEF) and FEV(1). RESULTS The addition of a 5-lipoxygenase (5-LO) inhibitor added to a low-dose of BDP showed no significant difference in FEV(1) compared to doubling the dose of BDP. FEV(1) improved in all 3 treatment groups, with mean increases of 10% with zileuton 600 mg QID+BDP 200 microg BID, 12% with zileuton 400mg QID+BDP 200 microg BID, and 11% with BDP 400 microg BID by study end. Within each treatment group, there were significant improvements in asthma symptoms and AM and PM PEF compared to baseline. No significant differences were observed between groups with regards to salbutamol use, acute asthma exacerbations, the requirement for oral/parenteral corticosteroids and adverse clinical events. CONCLUSIONS The addition of a 5-LO inhibitor added to low-dose beclomethasone may be an alternative to higher-doses of ICS in patients unable to achieve sufficient asthma control on low-dose ICS therapy.
Collapse
|
23
|
Peters-Golden M, Gleason MM, Togias A. Cysteinyl leukotrienes: multi-functional mediators in allergic rhinitis. Clin Exp Allergy 2006; 36:689-703. [PMID: 16776669 PMCID: PMC1569601 DOI: 10.1111/j.1365-2222.2006.02498.x] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Cysteinyl leukotrienes (CysLTs) are a family of inflammatory lipid mediators synthesized from arachidonic acid by a variety of cells, including mast cells, eosinophils, basophils, and macrophages. This article reviews the data for the role of CysLTs as multi-functional mediators in allergic rhinitis (AR). We review the evidence that: (1) CysLTs are released from inflammatory cells that participate in AR, (2) receptors for CysLTs are located in nasal tissue, (3) CysLTs are increased in patients with AR and are released following allergen exposure, (4) administration of CysLTs reproduces the symptoms of AR, (5) CysLTs play roles in the maturation, as well as tissue recruitment, of inflammatory cells, and (6) a complex inter-regulation between CysLTs and a variety of other inflammatory mediators exists.
Collapse
|
24
|
JOSEPHSON DAVIDB, LINDSAY ROBERTC, STUIBER DAVIDA. Enzymic Hydroperoxide Initiated Effects in Fresh Fish. J Food Sci 2006. [DOI: 10.1111/j.1365-2621.1987.tb06683.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
25
|
Aires V, Hichami A, Moutairou K, Khan NA. Docosahexaenoic acid and other fatty acids induce a decrease in pHi in Jurkat T-cells. Br J Pharmacol 2004; 140:1217-26. [PMID: 14645139 PMCID: PMC1574148 DOI: 10.1038/sj.bjp.0705563] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. Docosahexaenoic acid (DHA) induced rapid (t1/2=33 s) and dose-dependent decreases in pHi in BCECF-loaded human (Jurkat) T-cells. Addition of 5-(N,N-dimethyl)-amiloride, an inhibitor of Na+/H+ exchanger, prolonged DHA-induced acidification as a function of time, indicating that the exchanger is implicated in pHi recovery. 2. Other fatty acids like oleic acid, arachidonic acid, eicosapentaenoic acid, but not palmitic acid, also induced a fall in pHi in these cells. 3. To assess the role of calcium in the DHA-induced acidification, we conducted experiments in Ca2+-free (0% Ca2+) and Ca2+-containing (100% Ca2+) buffer. We observed that there was no difference in the degree of DHA-induced transient acidification in both the experimental conditions, though pHi recovery was faster in 0% Ca2+ medium than that in 100% Ca2+ medium. 4. In the presence of BAPTA, a calcium chelator, a rapid recovery of DHA-induced acidosis was observed. Furthermore, addition of CaCl2 into 0% Ca2+ medium curtailed DHA-evoked rapid pHi recovery. In 0% Ca2+ medium, containing BAPTA, DHA did not evoke increases in [Ca2+]i, though this fatty acid still induced a rapid acidification in these cells. These observations suggest that calcium is implicated in the long-lasting DHA-induced acidosis. 5. DHA-induced rapid acidification may be due to its deprotonation in the plasma membrane (flip-flop model), as suggested by the following observations: (1) DHA with a -COOH group induced intracellular acidification, but this fatty acid with a -COOCH3 group failed to do so, and (2) DHA, but not propionic acid, -induced acidification was completely reversed by addition of fatty acid-free bovine serum albumin in these cells. 6. These results suggest that DHA induces acidosis via deprotonation and Ca2+ mobilization in human T-cells.
Collapse
Affiliation(s)
- Virginie Aires
- UPRES Lipides and Nutrition, Université de Bourgogne, Faculté des Sciences de la vie, 6, Boulevard Gabriel, Dijon 21000, France
| | - Aziz Hichami
- UPRES Lipides and Nutrition, Université de Bourgogne, Faculté des Sciences de la vie, 6, Boulevard Gabriel, Dijon 21000, France
| | - Kabirou Moutairou
- UPRES Lipides and Nutrition, Université de Bourgogne, Faculté des Sciences de la vie, 6, Boulevard Gabriel, Dijon 21000, France
| | - Naim Akhtar Khan
- UPRES Lipides and Nutrition, Université de Bourgogne, Faculté des Sciences de la vie, 6, Boulevard Gabriel, Dijon 21000, France
- Author for correspondence:
| |
Collapse
|
26
|
Kikuta Y, Yamashita Y, Kashiwagi S, Tani K, Okada K, Nakata K. Expression and induction of CYP4F subfamily in human leukocytes and HL60 cells. Biochim Biophys Acta Mol Cell Biol Lipids 2004; 1683:7-15. [PMID: 15238214 DOI: 10.1016/j.bbalip.2004.03.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2003] [Revised: 03/24/2004] [Accepted: 03/31/2004] [Indexed: 11/28/2022]
Abstract
We investigated the expression of the CYP4F subfamily in human leukocytes and HL60 cells. Enzymatic activity assay, immunocytochemical staining, and reverse transcription-polymerase chain reaction (RT-PCR) analysis of human leukocytes showed that polymorphonuclear leukocytes (PMNs) expressed CYP4F3B and CYP4F12 in addition to CYP4F3. Transcription start site of CYP4F3B mRNA in the leukocytes was identical to that of CYP4F3 mRNA. The HL60 cells, which were differentiated into PMN-like shapes by treatment with all-trans-retinoic acid (RA), also expressed CYP4F3, CYP4F3B and CYP4F12. CYP4F3 was expressed in one third of the peripheral monocytes, which omega-hydroxylated leukotriene B(4) (LTB(4)) at a rate 11 times lower than that of PMN. The cells that were differentiated into a form similar to monocytes/macrophages in shape by treatment with 12-myristate 13-acetate expressed mRNA for CYP4F3 and CYP4F3B. Promoter analysis of the CYP4F3 gene demonstrated that a region (-174/-90) of this gene was important for its promoter activity in the HL60 cells. This is the first report on the distribution of different CYP4F isoforms in leukocytes and their induction in HL60 cells.
Collapse
Affiliation(s)
- Yasushi Kikuta
- Department of Applied Biological Science, Faculty of Life Science and Biotechnology, Fukuyama University, Gakuencho-1, Fukuyama, Hiroshima 729-0292, Japan.
| | | | | | | | | | | |
Collapse
|
27
|
Denys A, Aires V, Hichami A, Khan NA. Thapsigargin-stimulated MAP kinase phosphorylation via CRAC channels and PLD activation: inhibitory action of docosahexaenoic acid. FEBS Lett 2004; 564:177-82. [PMID: 15094063 DOI: 10.1016/s0014-5793(04)00361-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2004] [Revised: 03/09/2004] [Accepted: 03/11/2004] [Indexed: 11/17/2022]
Abstract
This study was conducted on human Jurkat T-cells to investigate the role of depletion of intracellular Ca(2+) stores in the phosphorylation of two mitogen-activated protein kinases (MAPKs), i.e. extracellular signal-regulated kinase (ERK) 1 and ERK2, and their modulation by a polyunsaturated fatty acid, docosahexaenoic acid (DHA). We observed that thapsigargin (TG) stimulated MAPK activation by store-operated calcium (SOC) influx via opening of calcium release-activated calcium (CRAC) channels as tyrphostin-A9, a CRAC channel blocker, and two SOC influx inhibitors, econazole and SKF-96365, diminished the action of the former. TG-stimulated ERK1/ERK2 phosphorylation was also diminished in buffer containing EGTA, a calcium chelator, further suggesting the implication of calcium influx in MAPK activation in these cells. Moreover, TG stimulated the production of diacylglycerol (DAG) by activating phospholipase D (PLD) as propranolol (PROP) (a PLD inhibitor), but not U73122 (a phospholipase C inhibitor), inhibited TG-evoked DAG production in these cells. DAG production and protein kinase C (PKC) activation were involved upstream of MAPK activation as PROP and GF109203X, a PKC inhibitor, abolished the action of TG on ERK1/ERK2 phosphorylation. Furthermore, DHA seems to act by inhibiting PKC activation as this fatty acid diminished TG- and phorbol 12-myristate 13-acetate-induced ERK1/ERK2 phosphorylation in these cells. Together these results suggest that Ca(2+) influx via CRAC channels is implicated in PLD/PKC/MAPK activation which may be a target of physiological agents such as DHA.
Collapse
Affiliation(s)
- Anne Denys
- Département de Physiologie, UPRES Lipides et Nutrition, Université de Bourgogne, Faculté des Sciences de la Vie, 6 Boulevard Gabriel, 21000 Dijon, France
| | | | | | | |
Collapse
|
28
|
Soberman RJ, Christmas P. The organization and consequences of eicosanoid signaling. J Clin Invest 2003. [DOI: 10.1172/jci200318338] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
29
|
Hichami A, Joshi B, Simonin AM, Khan NA. Role of three isoforms of phospholipase A2 in capacitative calcium influx in human T-cells. EUROPEAN JOURNAL OF BIOCHEMISTRY 2002; 269:5557-63. [PMID: 12423354 DOI: 10.1046/j.1432-1033.2002.03261.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The present study was conducted on human Jurkat T-cell lines in order to elucidate the role of phospholipase A2 in capacitative calcium entry. We have employed thapsigargin (TG) that induces increases in [Ca2+]i by emptying the calcium pool of endoplasmic reticulum, followed by capacitative calcium entry. We designed a Ca2+ free/Ca2+ reintroduction (CFCR) protocol for the experiments, conducted in Ca2+-free medium. By employing CFCR protocol, we observed that addition of exogenous arachidonic acid (AA) stimulated TG-induced capacitative calcium influx. The liberation of endogenous AA and its autocrine action seems to be implicated during TG-induced capacitative calcium influx: TG potentiates the induction of constitutively expressed mRNA of four PLA2 isoforms (type 1B, IV, V, VI), the inhibitors of the three PLA2 isotypes (type 1B, V, VI) inhibit TG-induced release of [3H]AA into the extracellular medium, and finally, these PLA2 inhibitors do curtail TG-stimulated capacitative calcium entry in these cells. These results suggest that stimulation of three isoforms of PLA2 by thapsigargin liberates free AA that, in turn, induces capacitative calcium influx in human T-cells.
Collapse
Affiliation(s)
- Aziz Hichami
- UPRES Lipides & Nutrition, Université de Bourgogne 21000 Dijon, France; Central Jalma Research Institute for Leprosy, Agra, UP, India
| | | | | | | |
Collapse
|
30
|
Abstract
We observed that human (Jurkat) T-cells constitutively expressed the mRNA, encoding for the four isoforms of phospholipase A(2) (PLA(2)), i.e. two secretory (type IB and type V), and two cytosolic (type IV, Ca(2+)-dependent and type VI, Ca(2+)-independent). In order to assess whether these PLA(2) isoforms are active, we labeled Jurkat T-cells with [(3)H]arachidonic acid ([(3)H]AA) and determined its release into the extracellular medium in the presence of phorbol 12-myristate 13-acetate (PMA) and ionomycin. The three PLA(2) isoforms seem functional as aristolochic acid and bromoenol lactone (BEL), the respective inhibitors of type IB/type V and type VI PLA(2)s, significantly inhibited the release of free [(3)H]AA. On the other hand, arachidonyl trifluoromethyl ketone (AACOCF(3)), an inhibitor of type IV PLA(2), failed to curtail significantly the release of free [(3)H]AA into the extracellular medium. We assessed the implication of these PLA(2) isoforms in transcription of the interleukin-2 (IL-2) gene, involved in T-cell proliferation. Hence, aristolochic acid and BEL, but not AACOCF(3), significantly inhibited the PMA and ionomycin-induced induction of mRNA of IL-2. Similarly, aristolochic acid and BEL, but not AACOCF(3), significantly inhibited the PMA and ionomycin-induced secretion of IL-2 in the culture supernatants. Together these results suggest that human Jurkat T-cells possess two secretory and two cytosolic PLA(2) isoforms and only three of them (type IB, type V and type VI) are implicated in T-cell proliferation.
Collapse
Affiliation(s)
- Christian Tessier
- UPRES Lipides and Nutrition, Université de Bourgogne, Faculté des Sciences de la Vie, 6 Boulevard Gabriel, 21000 Dijon, France
| | | | | |
Collapse
|
31
|
Yang XY, Wang LH, Mihalic K, Xiao W, Chen T, Li P, Wahl LM, Farrar WL. Interleukin (IL)-4 indirectly suppresses IL-2 production by human T lymphocytes via peroxisome proliferator-activated receptor gamma activated by macrophage-derived 12/15-lipoxygenase ligands. J Biol Chem 2002; 277:3973-8. [PMID: 11726648 DOI: 10.1074/jbc.m105619200] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The respective development of either T helper type 1 (Th1) or Th2 cells is believed to be mediated by the effects of cytokines acting directly on Th precursors (Thp). We have generated evidence for an indirect monocyte-dependent immunoregulatory pathway. Recently, interleukin (IL) 4 has been shown to produce "new" potential peroxisome proliferator-activated receptor gamma (PPARgamma) ligands by inducing macrophage 12/15-lipoxygenase (12/15-LO). We have shown previously that the activated PPARgamma is a profound inhibitor of IL-2 transcription in human T lymphocytes. It is hypothetically possible that IL-4 might indirectly affect IL-2 production by Thp cells via macrophage-derived PPARgamma ligands. Using human monocytes and T lymphocytes from same donors, we have found that monocyte 12/15-LO products mediate the indirect inhibitory effect of IL-4 on anti-CD3- or phytohemagglutinin/phorbol 12-myristate 13-acetate-stimulated IL-2 production by T lymphocytes. We further analyzed which major 12/15-LO metabolites contributed to the above inhibition. 13-Hydroxyoctadecadienoic acid (13-HODE), a 12/15-LO product, markedly blocked IL-2 production by human blood T lymphocytes, but not Jurkat T cells. Moreover, the IL-4-conditioned macrophage medium contained a sufficient amount of 13-HODE and anti-13-HODE antibody indeed neutralized the inhibitory effects of the IL-4-conditional medium on T-cell IL-2 production. Using human T lymphocytes and the PPARgamma-transfected Jurkat T cells, we demonstrated the specific inhibition by 13-HODE of the transcription factors NFAT (nuclear factor of activated T cells) and nuclear factor kappaB, the IL-2 promoter reporter, and IL-2 production. However, 15-hydroxytetraenoic acid had little inhibitory effect. The potency of such inhibitory effects correlates well with the capability of the above metabolic lipids to activate PPARgamma. These data provide a mechanism whereby IL-4 may indirectly affect Thp function via PPARgamma activated by macrophage products of the 12/15-LO pathway.
Collapse
Affiliation(s)
- Xiao Yi Yang
- Intramural Research Support Program, Science Applications International Corporation, Frederick, MD 21702, USA
| | | | | | | | | | | | | | | |
Collapse
|
32
|
Eicosapentaenoic acid and docosahexaenoic acid modulate MAP kinase (ERK1/ERK2) signaling in human T cells. J Lipid Res 2001. [DOI: 10.1016/s0022-2275(20)31530-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
33
|
Krawiec ME, Wenzel SE. Leukotriene inhibitors and non-steroidal therapies in the treatment of asthma. Expert Opin Pharmacother 2001; 2:47-65. [PMID: 11336568 DOI: 10.1517/14656566.2.1.47] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Asthma is the most common chronic disease of childhood whose morbidity and mortality continues to rise [1]. Drugs used in the treatment of asthma must be targeted at reversing three principle pathophysiologic features: bronchoconstriction, mucus plugging/hypersecretion and inflammation. In the past two decades, the contribution of airway inflammation to the development and progression of asthma symptoms and airway pathology has become a critical focus. Chronic airway inflammation can lead to the progressive decline and irreversible loss of lung function and airway remodelling [2]. In recent years, therapies aimed at diminishing airway inflammation have been at the forefront of asthma management. Steroids have been extensively studied and used as primary anti-inflammatory agents in the management of the asthmatic patient with persistent symptoms of varying severity. Within the last decade, however, several additional non-steroidal classes of drugs have begun to emerge as anti-inflammatory agents for the treatment of asthma. This article will focus on these non-steroidal drugs which have been developed and investigated within the last 5 years. Particular emphasis will be placed on leukotriene receptor antagonists, but anti-IgE and anti-IL-4 therapies, as well as phosphodiesterase inhibitors will also be discussed. Of these new therapies, only two leukotriene receptor antagonists, montelukast (Singulairtrade mark, Merck) and zafirlukast (Accolatetrade mark, AstraZeneca) and the 5-lipoxygenase inhibitor, zileuton (Zyflotrade mark, Abbott Laboratories), have been recommended, approved and are currently available for use in the treatment of paediatric patients with asthma in the United States.
Collapse
Affiliation(s)
- M E Krawiec
- University of Wisconsin, Department of Pediatric Pulmonology, 600 Highland Avenue, K4/944, Madison, WI 53792-4108, USA.
| | | |
Collapse
|
34
|
Abstract
Leukotrienes have been shown to cause bronchoconstriction, increased mucus production, and airway inflammation, three critical features in asthma. Antileukotriene drugs were developed to inhibit the effects of these lipid mediators. This class of drugs represents the first new approach to asthma therapy in 25 years. The leukotriene receptor antagonists, montelukast, zafirlukast, and pranlukast, and the 5-lipoxygenase inhibitor, zileuton, are unique in their ability to target specific components of asthmatic inflammation. Although the role of these drugs continues to evolve, the antileukotrienes have demonstrated efficacy against exercise and allergen-induced bronchoconstriction and additive benefit for use in patients with symptomatic, moderate asthma on maintenance-inhaled corticosteroids. Further, they may be considered for primary use in patients with mild, persistent asthma, especially those who are steroid-phobic or who have compliance issues.
Collapse
Affiliation(s)
- M E Krawiec
- Department of Pediatrics, National Jewish Medical and Research Center, Denver, Colorado, USA.
| | | |
Collapse
|
35
|
Constable AL, Armati PJ, Hartung HP. DMSO induction of the leukotriene LTC4 by Lewis rat Schwann cells. J Neurol Sci 1999; 162:120-6. [PMID: 10202977 DOI: 10.1016/s0022-510x(98)00320-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Schwann cells are capable of producing many immunomodulatory molecules, which indicates that they may play an active role in autoimmune diseases of the peripheral nervous system. We have previously reported production of the prostanoids prostaglandin E2 and thromboxane A2, products of arachidonic acid metabolism, by Schwann cells. This study reports that Schwann cells are capable of producing leukotriene C4, also a product of arachidonic acid metabolism. Production of leukotriene C4 was in response to pre-incubation of the Schwann cells with the cytokines interferon-gamma and tumour necrosis factor-alpha followed by incubation with dimethylsulfoxide. The cytokines alone did not elicit a response nor did stimulation with calcium ionophore, phorbol ester or lipopolysaccharide.
Collapse
Affiliation(s)
- A L Constable
- School of Biological Sciences, The University of Sydney, NSW, Australia
| | | | | |
Collapse
|
36
|
Chavis C, Vachier I, Bousquet J, Godard P, Chanez P. Generation of eicosanoids from 15(S)-hydroxyeicosatetraenoic acid in blood monocytes from steroid-dependent asthmatic patients. Biochem Pharmacol 1998; 56:535-41. [PMID: 9763231 DOI: 10.1016/s0006-2952(98)00086-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aim of this study was to investigate eicosanoid metabolism by human peripheral blood monocytes (PBM) from steroid-dependent asthmatic patients as compared to control subjects and untreated asthmatic patients. Eicosanoid biosynthesis by PBM isolated from venous blood using Percoll gradient centrifugation was evaluated following stimulation of 5 x 10(6) cells with calcium ionophore A23187, with or without exogenous 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), and analyzed by reverse phase high performance liquid chromatography (RP-HPLC). Without 15(S)-HETE, PBM synthesized leukotriene B4 (LTB4) only (40 +/- 12 ng and 59 +/- 11 ng for untreated and steroid-dependent asthmatics, respectively). In the presence of 15(S)-HETE, PBM produced six-fold smaller amounts of leukotriene B4 (P < 0.0001). They also released 5(S),15(S)-dihydroxyeicosatetraenoic acid (5(S),15(S)-diHETE) in similar amounts for all the populations, whereas low amounts of lipoxins (LXs) were produced by PBM from asthmatics only (2.7 +/- 0.7 ng and 4.6 +/- 2.8 ng for untreated and steroid-dependent asthmatics, respectively). Moreover, PBM were also able to release an unknown compound containing conjugated triene chromophore. Cells from steroid-dependent asthmatic patients synthesized this unknown metabolite in higher amounts than controls and untreated asthmatics (133 +/- 18 ng vs 52 +/- 19 ng and 68 +/- 15 ng, respectively, P < 0.02). This work shows for the first time that human PBM are able to metabolize 15(S)-HETE and lead to lipoxins and to an unknown metabolite, with the amounts of the latter being enhanced by long-term corticosteroid treatment.
Collapse
Affiliation(s)
- C Chavis
- INSERM U 454-IFR 3, Hôpital Arnaud de Villeneuve, Montpellier, France.
| | | | | | | | | |
Collapse
|
37
|
Abstract
LEARNING OBJECTIVES Reading this article will reinforce the reader's knowledge of the biochemistry and pharmacology of leukotrienes (LTs), including the enzymes and cells involved in their synthesis, the receptors that mediate their biologic effects, and the evidence that cysteinyl leukotrienes (CysLT) may play an important role in asthma. The 5-lipoxygenase inhibitors, 5-lipoxygenase-activating protein antagonists, and CysLT receptor antagonists are three classes of LTs modulators now in clinical use. The effects of these agents in clinical models of asthma induced by allergens, exercise, and aspirin and in multicenter asthma trials are reviewed. DATA SOURCES Key papers published in peer-reviewed journals. STUDY SELECTION Key papers published in peer-reviewed journals. CONCLUSIONS The pharmacology of these new medications and experience in clinical trials suggest that they may play a therapeutic role in the treatment of asthma.
Collapse
Affiliation(s)
- W Busse
- Department of Medicine, University of Wisconsin-Madison, 53792-3244, USA
| |
Collapse
|
38
|
Riddick CA, Ring WL, Baker JR, Hodulik CR, Bigby TD. Dexamethasone increases expression of 5-lipoxygenase and its activating protein in human monocytes and THP-1 cells. EUROPEAN JOURNAL OF BIOCHEMISTRY 1997; 246:112-8. [PMID: 9210472 DOI: 10.1111/j.1432-1033.1997.00112.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The aim of this study was to assess the effect of dexamethasone on 5-lipoxygenase pathway expression in human peripheral blood monocytes and the acute monocytic leukemia cell line, THP-1. Cells were conditioned over a period of days with dexamethasone, at concentrations relevant in vivo, to study the effect of the glucocorticoid on calcium-ionophore-stimulated 5-lipoxygenase product and arachidonic acid release. The effect of dexamethasone on levels of immunoreactive protein and steady-state messenger RNA encoding for 5-lipoxygenase and its activating protein (5-LAP) was also assessed. Dexamethasone increased the stimulated release of 5-lipoxygenase products from both monocytes and THP-1 cells in a dose-dependent fashion. The increase in product generation was not due to changes in the availability of arachidonic acid. However, immunoreactive protein and steady-state messenger RNA encoding for 5-lipoxygenase and 5-LAP were increased by conditioning with dexamethasone. There was no apparent effect of the glucocorticoid on LTA4-hydrolase-immunoreactive protein levels or specific activity. We conclude that dexamethasone increases 5-lipoxygenase pathway expression in both monocytes and in THP-1 cells. This effect is due, at least in part, to increases in immunoreactive protein and steady-state messenger RNA encoding for 5-lipoxygenase and 5-LAP. These results suggest a role for glucocorticoids in the regulation of 5-lipoxygenase pathway expression in mononuclear phagocytes.
Collapse
Affiliation(s)
- C A Riddick
- Department of Veteran Affairs Medical Center, San Diego, CA 92161, USA
| | | | | | | | | |
Collapse
|
39
|
Nassar GM, Montero A, Fukunaga M, Badr KF. Contrasting effects of proinflammatory and T-helper lymphocyte subset-2 cytokines on the 5-lipoxygenase pathway in monocytes. Kidney Int 1997; 51:1520-8. [PMID: 9150468 DOI: 10.1038/ki.1997.209] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Human peripheral blood monocytes (HPBMs) express 5-lipoxygenase (5-LO) and 5-LO activating protein (FLAP), and hence have an ability to synthesize proinflammatory leukotrienes (LTs). Regulation of 5-LO and FLAP expression is a major determinant of cellular LT synthesis. We examined the effects of proinflammatory [interleukin (IL)-1 and interferon (IFN)-gamma] and T helper lymphocyte subset 2 (TH-2; IL-4 and IL-13) cytokines on (1) LTB4 production, and (2) 5-LO and FLAP expression in HPBMs. We show that IL-1 and IFN-gamma stimulate, whereas IL-4 and IL-13 inhibit ionophore-activated LTB4 release. The stimulatory effects of IL-1 and IFN-gamma were apparent at 16 to 36 hours of incubation. IL-1 modestly increased FLAP mRNA and significantly increased 5-LO mRNA steady state levels at 24 and 36 hours of incubation, respectively. IFN-gamma did not change the mRNA or protein expression of either 5-LO or FLAP. The inhibitory effects of IL-4 and IL-13 were associated with decreased FLAP mRNA and protein steady state levels. These results demonstrate that regulation of monocyte LTB4 biosynthesis by different cytokines proceeds via different pathways that partly involve modulation of the expression of the key proteins, 5-LO and FLAP. In addition, the contrasting effects of proinflammatory and TH-2-derived cytokines on monocyte LTB4 production demonstrate mechanisms by which cytokine subpopulations may modulate monocyte function in inflammation.
Collapse
Affiliation(s)
- G M Nassar
- Renal Divisions of Emory University, Atlanta, Georgia, USA
| | | | | | | |
Collapse
|
40
|
Liu MC, Dubé LM, Lancaster J. Acute and chronic effects of a 5-lipoxygenase inhibitor in asthma: a 6-month randomized multicenter trial. Zileuton Study Group. J Allergy Clin Immunol 1996; 98:859-71. [PMID: 8939149 DOI: 10.1016/s0091-6749(96)80002-9] [Citation(s) in RCA: 196] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Leukotrienes produced by the 5-lipoxygenase pathway of arachidonic acid metabolism may mediate bronchoconstriction and inflammatory changes important in the pathophysiology of asthma. Leukotriene inhibition may be effective in asthma management. OBJECTIVE This clinical trial was performed to assess the long-term efficacy and safety of zileuton, an inhibitor of 5-lipoxygenase. METHODS In this multicenter, double-blind, parallel-group, placebo-controlled trial, 600 mg of zileuton, 400 mg of zileuton, or placebo was given orally, each four times daily for 6 months. Patients with mild to moderate asthma (n = 373), 18 to 62 years of age, being managed with regularly inhaled beta-agonist alone, were randomized to the zileuton or placebo groups (n = 122 to 126). Outcome measures included serial spirometry, daily peak expiratory flow rates, daytime and nocturnal symptoms, frequency of beta-agonist use, and number of asthma exacerbations treated with systemic corticosteroids. RESULTS An acute bronchodilatory effect was observed 2 to 5 hours after the initial dose of medication in both 400 mg zileuton and 600 mg zileuton groups compared to the placebo group. Both zileuton groups had significantly greater improvements in FEV1 than did the placebo group by day 8. On day 36, FEV1 improved 16% and 12% from baseline for patients treated with 600 mg zileuton and 400 mg zileuton, respectively, compared with an improvement of 6% for the placebo-treated group (p < 0.01, zileuton 600 mg vs placebo). Blood eosinophil levels were significantly reduced in both zileuton-treated groups compared with the placebo group. In the group receiving 600 mg zileuton, morning peak expiratory flow rate improved by 7% to 10%; daytime and nocturnal symptoms decreased by 37% and 31%, respectively; beta-agonist use decreased by 31%; and the proportion of patients requiring steroid rescue medication during the study was reduced by 62% (p < 0.05 for all comparisons of zileuton, 600 mg, vs placebo). Improvements were sustained over 6 months. Adverse events were similar in the three groups with no apparent, dose-related side effects. CONCLUSION Zileuton produces objective and subjective improvements in patients with mild to moderate asthma and is well tolerated.
Collapse
Affiliation(s)
- M C Liu
- Department of Medicine, Johns Hopkins Asthma and Allergy Center, Baltimore, MD 21224-6801, USA
| | | | | |
Collapse
|
41
|
Martin CA, Félétou M, Lonchampt M, Dacquet C, Dhainaut A, Canet E. In vitro pharmacological effects of S 12370 (2-[4-benzhydryloxypiperidinoethyl]isoxindole; an antibronchoconstrictor agent) in normal and sensitized tissue. Fundam Clin Pharmacol 1996; 10:458-66. [PMID: 8902549 DOI: 10.1111/j.1472-8206.1996.tb00601.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effects of S 12370 (2-[4-benzhydryloxypiperidinoethyl]isoxindole), were studied in vitro. In guinea pig isolated tracheal rings, S 12370 induced a similar competitive inhibition of the contractile responses produced by acetylcholine, histamine and serotonin. However, it did not affect the contractions induced by leukotriene D4 (LTD4), substance P and U 46619, a stable analogue of thromboxane A2. S 12370 induced a concentration dependent inhibition of the cholinergic component of the contraction induced by electrical field stimulation, whereas it did not influence the sustained nonadrenergic noncholinergic (NANC) excitatory response observed in guinea pig isolated bronchi. S 12370 did not influence the relaxations induced by prostaglandin E2, isoprenaline and salbutamol, and did not modify the nonadrenergic noncholinergic inhibitory response induced by electrical field stimulation. In isolated left atria, the negative inotropic effect of acetylcholine was competitively inhibited by S 12370. In binding experiments, S 12370 exhibited similar affinity for M1, M2, M3, M4 muscarinic receptors and also recognized 5-HT2 serotonin and H1 histamine receptor subtypes. In ovalbumin-sensitized animals, the contractile response of isolated tracheal rings produced by exposure to the allergen was not influenced by S 12370. Tracheal rings from sensitized animals preexposed in vitro to the allergen developed a hyporesponsiveness to beta-adrenoceptor stimulation. S 12370 prevented the inhibitory effect caused by ovalbumin immune sensitization in the relaxation to isoprenaline. In rat polymorphonuclear neutrophil (PMN) cells, S 12370 up to 10(-5) M did not inhibit the arachidonic acid metabolism. These results suggest that in guinea pig tracheal smooth muscle, S 12370 is a competitive inhibitor of muscarinic, serotonin and histamine receptors and can modulate the beta-adrenergic dysfunction induced by immune sensitization. S 12370 may present some therapeutic interest in inflammatory airway diseases.
Collapse
MESH Headings
- 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid
- Acetylcholine/toxicity
- Animals
- Arachidonic Acid/metabolism
- Benzhydryl Compounds/metabolism
- Benzhydryl Compounds/pharmacology
- Binding, Competitive
- Electric Stimulation
- Guinea Pigs
- Heart/drug effects
- Histamine/toxicity
- Leukotriene D4/toxicity
- Lung/drug effects
- Lung/metabolism
- Male
- Muscle Contraction/drug effects
- Muscle, Smooth/drug effects
- Muscle, Smooth/metabolism
- Muscle, Smooth, Vascular/drug effects
- Ovalbumin/toxicity
- Oxindoles
- Prostaglandin Endoperoxides, Synthetic/toxicity
- Rats
- Receptors, Adrenergic, beta/drug effects
- Receptors, Adrenergic, beta/metabolism
- Serotonin/toxicity
- Substance P/toxicity
- Thromboxane A2/analogs & derivatives
- Thromboxane A2/toxicity
- Vasoconstrictor Agents/toxicity
- Vasodilator Agents/pharmacology
Collapse
Affiliation(s)
- C A Martin
- Laboratoire de Pharmacologie Expérimentale et Moléculaire, Faculte des Sciences Pharmaceutiques et Biologiques, Rennes, France
| | | | | | | | | | | |
Collapse
|
42
|
Affiliation(s)
- P C Calder
- Department of Biochemistry, University of Oxford
| |
Collapse
|
43
|
Sjölinder M, Tornhamre S, Werga P, Edenius C, Lindgren JA. Phorbol ester-induced suppression of leukotriene C4 synthase activity in human granulocytes. FEBS Lett 1995; 377:87-91. [PMID: 8543026 DOI: 10.1016/0014-5793(95)01303-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The effect of the protein kinase C activator, phorbol 12-myristate 13-acetate (PMA), on the metabolism of exogenous leukotriene (LT)A4 in human granulocytes was investigated. After incubation with LTA4 decreased levels of LTC4 but not LTB4 were observed in granulocyte suspensions pretreated with PMA. This finding could in part be ascribed to oxidative metabolism of LTC4, since PMA induced a rapid degradation of exogenously added LTC4. After blocking of LTC4 metabolism with the H2O2 scavenger catalase, a PMA-provoked suppression of the conversion of LTA4 to LTC4 was observed, indicating PKC-dependent regulation of LTC4 synthase activity. This effect, as well as PMA-induced degradation of LTC4 was prevented by specific protein kinase C inhibitors.
Collapse
Affiliation(s)
- M Sjölinder
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | | | | | | | | |
Collapse
|
44
|
Dolhain RJ, de Kuiper P, Verweij CL, Penders JM, Breedveld FC, Dijkmans BA, Miltenburg AM. Tenidap, but not nonsteroidal anti-inflammatory drugs, inhibits T-cell proliferation and cytokine induction. Scand J Immunol 1995; 42:686-93. [PMID: 8552993 DOI: 10.1111/j.1365-3083.1995.tb03712.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
T-lymphocytes are involved in the inflammatory response that occurs in affected joints of patients with rheumatoid arthritis (RA). Some second-line disease modifying anti-rheumatic drugs used in the treatment of patients with RA are known to block T-cell activation. The present study assessed whether tenidap, an investigational anti-rheumatic drug, affects in vitro T-cell responses such as proliferation and cytokine production. It was found that tenidap, in contrast to several nonsteroidal anti-inflammatory drugs, inhibits anti-CD3 or IL-2 driven proliferative responses of cloned human T-cells. Furthermore, tenidap was found to inhibit IFN-gamma production as well as the induction of mRNA encoding IFN-gamma or TNF-alpha. The results indicate that tenidap may exert at least part of its anti-inflammatory activity via inhibition of T-cell function and cytokine production.
Collapse
Affiliation(s)
- R J Dolhain
- Department of Rheumatology, University Hospital Leiden, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
45
|
Miadonna A, Milazzo N, Lorini M, Marchesi E, Tedeschi A. Antiallergic activity of loratadine: inhibition of leukotriene C4 release from human leucocytes. Clin Exp Allergy 1995; 25:364-70. [PMID: 7541309 DOI: 10.1111/j.1365-2222.1995.tb01055.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The H1 antagonist loratadine has the capacity to inhibit histamine release from human basophils. The aim of this study was to investigate whether loratadine can also inhibit leukotriene C4 (LTC4) release from human leucocytes. Basophil-enriched mononuclear cell suspensions were prepared by centrifugation of peripheral venous blood (n = 10) on discontinuous Percoll gradients. Leucocytes were stimulated with anti-IgE, N-formylmethionyl-leucyl-phenylalanine (FMLP) and Ca2+ ionophore A23187; immunoreactive (i) LTC4 release in the cell supernatant was measured by a competitive radioimmunoassay and histamine release was evaluated by an automated fluorometric technique. Loratadine, in the concentration range of 1-50 microM, exerted a dose-dependent inhibitory effect on IgE-mediated and IgE-independent histamine and iLTC4 release. The concentrations inhibiting 50% of histamine release were 30 microM (anti-IgE), 27 microM (FMLP) and 19 microM (Ca2+ ionophore A23187). The concentrations inhibiting 50% of iLTC4 release were 2.3 microM (anti-IgE). 11 microM (FMLP) and 1.7 microM (Ca2+ ionophore A23187). The inhibitory activity on iLTC4 release was optimal after preincubation for 2 h at 37 degrees C, and was no longer evident when leucocytes were stimulated 2 h after cell washing. Increased extracellular Ca2+ concentrations reduced the inhibitory activity of loratadine. These results indicate that loratadine has the capacity to inhibit the release of preformed and newly generated mediators from human basophil-enriched mononuclear cell suspensions.
Collapse
Affiliation(s)
- A Miadonna
- Department of Internal Medicine, University of Milan, Ospedale Maggiore Policlinico, Italy
| | | | | | | | | |
Collapse
|
46
|
Cifone MG, Cironi L, Santoni A, Testi R. Diacylglycerol lipase activation and 5-lipoxygenase activation and translocation following TCR/CD3 triggering in T cells. Eur J Immunol 1995; 25:1080-6. [PMID: 7737277 DOI: 10.1002/eji.1830250433] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Arachidonic acid (AA) release was observed following T cell receptor (TCR)/CD3 complex cross-linking in different tumor T cell lines as well as on purified peripheral T cells in vivo. Direct measurement of enzymatic activity in vitro of TCR/CD3-stimulated Jurkat cell extracts on labeled vesicle substrates showed that TCR/CD3 cross-linking resulted in AA release from sn-1,2-diacylglycerol (DAG) vesicles, as detected by TLC analysis, suggesting that DAG lipase was activated following TCR/CD3 stimulation and DAG generation. On the contrary, no phospholipase A2 activation was observed in response to TCR/CD3 stimulation, since no lyso-phospholipids were generated in vitro from either phosphatidylcholine or phosphatidylinositol-3,4-bisphosphate, or from phosphatidic acid vesicles. Moreover, the 1-DAG lipase inhibitor RHC80267 completely blocked TCR/CD3-dependent AA release in vitro and in vivo, without effect upon TCR/CD3-dependent inositol-1,4,5-trisphosphate (IP3) generation. Importantly, evidence for further metabolism of released AA was obtained, since synthesis and release of cysteinyl leukotrienes (CLT), but not of leukotriene B4 or cyclooxygenase products, could be detected by radioimmunoassay in different T cell lines and peripheral blood T cells following TCR/CD3 cross-linking. Moreover, HPLC analysis revealed an accumulation of leukotriene E4 in TCR/CD3 stimulated Jurkat cells. This was associated with translocation of 5-lipoxygenase from the cytosol to the cell membranes. Finally, TCR/CD3-mediated CLT production was blocked by MK886, a specific inhibitor of 5-LO translocation and activation. Our data help define a further level in the fate of second messengers generated after TCR/CD3 triggering and suggest that additional mediators can play a role in the context of T cell activation.
Collapse
Affiliation(s)
- M G Cifone
- Department of Experimental Medicine, University of L'Aquila, Italy
| | | | | | | |
Collapse
|
47
|
Affiliation(s)
- F Grimminger
- Department of Internal Medicine, Justus Liebig University Giessen, Germany
| | | |
Collapse
|
48
|
Stenke L, Reizenstein P, Lindgren JA. Leukotrienes and lipoxins--new potential performers in the regulation of human myelopoiesis. Leuk Res 1994; 18:727-32. [PMID: 7934130 DOI: 10.1016/0145-2126(94)90053-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Leukotrienes and lipoxins are bioactive lipoxygenase products formed by leukocytes alone or in collaboration with other cells. While the physiological role of lipoxins remains to be clarified, accumulating evidence shows that leukotrienes are important mediators in asthma and inflammation. Consequently, recent clinical trials with leukotriene D4 receptor antagonists and 5-lipoxygenase inhibitors have demonstrated marked reduction of airway symptoms in asthmatic patients. In addition, both leukotrienes and lipoxins have been indicated as modulators of cell proliferation. This article reviews recent findings suggesting that these compounds may also participate in the regulation of human myelopoiesis. Such a role is conceivable since leukotrienes and lipoxins can be produced by bone marrow cells and potently modulate GM-CSF-induced myeloid stem cell proliferation.
Collapse
Affiliation(s)
- L Stenke
- Department of Medical Biochemistry and Biophysics, Danderyd Hospital, Sweden
| | | | | |
Collapse
|
49
|
Steinhilber D. 5-Lipoxygenase: enzyme expression and regulation of activity. PHARMACEUTICA ACTA HELVETIAE 1994; 69:3-14. [PMID: 7938075 DOI: 10.1016/0031-6865(94)90024-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
5-Lipoxygenase catalyzes the transformation of arachidonic acid to leukotriene A4. This unstable intermediate can be converted to leukotriene B4 by LTA4-hydrolase or to leukotriene C4 by LTC4-synthase. Leukotrienes are involved in host defense reactions and play an important role in inflammatory diseases like asthma, inflammatory bowel disease and arthritis. The capability to release leukotrienes is restricted to a few cell types. Under pathophysiological conditions, leukotrienes are released from granulocytes, mast cells or macrophages. During hematopoiesis the competence of these cells for leukotriene biosynthesis is supposed to be upregulated. In mature cells, 5-lipoxygenase activity is tightly regulated and seems to be under the control of additional cellular components. One cellular component, a membrane-bound peptide termed FLAP, which is necessary for 5-LO activity in intact cells has been recently identified. Inhibitors of FLAP function prevent translocation of 5-lipoxygenase from cytosol to the membrane and inhibit 5-LO activation. Thus, the understanding of the regulatory mechanisms of cellular leukotriene biosynthesis provides new concepts for the development of antiinflammatory drugs. This review focuses on the regulation of gene expression and activity of 5-lipoxygenase.
Collapse
Affiliation(s)
- D Steinhilber
- Dept. of Pharmaceutical Chemistry, University of Tübingen, Germany
| |
Collapse
|
50
|
Sellmayer A, Goessl C, Obermeier H, Volk R, Reder E, Weber C, Weber PC. Differential induction of eicosanoid synthesis in monocytic cells treated with retinoic acid and 1,25-dihydroxy-vitamin D3. PROSTAGLANDINS 1994; 47:203-20. [PMID: 8016390 DOI: 10.1016/0090-6980(94)90061-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Synthesis and release of eicosanoids is characteristic to mature monocytes, while in undifferentiated premonocytic cells arachidonic acid (AA) metabolism is barely detectable. Since some vitamins and cytokines induce differentiation of these cells to a more monocyte-like cell type, we evaluated the effect of retinoic acid (RA), 1,25(OH)2-vitamin D3 (1,25-D3) and interferon-gamma (IFN-gamma) on AA metabolism in the human premonocytic cell lines U937 and THP-1. In U937 cells, differentiation with RA (1 microM) followed by stimulation with the calcium ionophore A23187 (10 microM) or platelet activating factor (PAF; 100 nM) significantly increased synthesis of immunoreactive 6-keto PGF1 alpha, TxB2 and PGE2 5- to 6-fold. Analysis of AA metabolism in RA-differentiated cells prelabelled with [3H]-AA revealed the formation of additional radioactive compounds which coeluted with standards for PGF2 alpha, PGD2 and 12-hydroxyheptadecatrienoic acid (HHT). The structural identity of 6-keto PGF1 alpha, TxB2, PGE2 and HHT was confirmed by gas chromatography-mass spectrometry (GC-MS). In parallel, RA induced the expression of the monocytic surface antigen CD11b, but not CD14. Differentiation with 1,25-D3 (10 nM) only marginally increased stimulated eicosanoid formation, while it more effectively induced expression of CD11b and CD14. Pretreatment with IFN-gamma (100 IU/ml) slightly increased stimulus-dependent AA metabolism, but did not induce expression of CD11b or CD14. Induction of eicosanoid synthesis by RA was further confirmed in THP-1 cells. These data indicate that RA most effectively induced cyclooxygenase activity and stimulus-dependent eicosanoid formation in U937 and THP-1 cells. Furthermore, since expression of monocytic surface antigens differed between RA and 1,25-D3, it is suggested that induction of cyclooxygenase activity may correlate to differentiation into distinct monocytic phenotypes.
Collapse
Affiliation(s)
- A Sellmayer
- Institut für Prophylaxe und Epidemiologie der Kreislaufkrankheiten, Universität München, Germany
| | | | | | | | | | | | | |
Collapse
|