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Alegre NS, Garcia CC, Billordo LA, Ameigeiras B, Poncino D, Benavides J, Colombato L, Cherñavsky AC. Limited expression of TLR9 on T cells and its functional consequences in patients with nonalcoholic fatty liver disease. Clin Mol Hepatol 2019; 26:216-226. [PMID: 31795627 PMCID: PMC7160356 DOI: 10.3350/cmh.2019.0074] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 10/22/2019] [Indexed: 02/07/2023] Open
Abstract
Background/Aims Toll-like receptors (TLRs) modulate T cell responses in diverse diseases. Co-stimulation of T cell activation via TLR9 induces production of interferon gamma (IFN-γ), priming of which is critical for differentiation of pro-inflammatory macrophages. These macrophages have a crucial role in nonalcoholic fatty liver disease (NAFLD). We aimed to evaluate the expression of TLR9 protein on T cells and the consequences of TLR9-mediated triggering of these cells in patients with NAFLD.
Methods Our study included 34 patients with simple steatosis, 34 patients with nonalcoholic steatohepatitis, eight patients with NAFLD who met general diagnostic criteria but lacked histological diagnosis, and 51 control subjects. We used a synthetic TLR9 ligand to co-stimulate T cells. We measured TLR9 expression in liver and peripheral T cells and CD69 and IFN-γ as phenotypic markers of T cell activation and differentiation by flow cytometry.
Results TLR9 expression on liver and peripheral T cells was lowest in patients with simple steatosis and was positively associated with anthropometric, biochemical, and histopathological features of NAFLD. In vitro co-stimulation of T cells from patients with simple steatosis induced a limited number of IFN-γ-producing CD8+ T cells. At baseline, these patients showed a low frequency of circulating type 1 CD8+ cells.
Conclusions The positive associations between TLR9 and anthropometric, clinical, and histological features and the crucial role of IFN-γ-in NAFLD suggest that limited TLR9 expression and production of IFN-γ play a protective role in patients with simple steatosis.
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Affiliation(s)
- Nadia Soledad Alegre
- Instituto de Inmunología, Genética y Metabolismo, Universidad de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Farmacia y Bioquímica, Hospital de Clínicas "José de San Martín", Buenos Aires, Argentina
| | - Cecilia Claudia Garcia
- Instituto de Inmunología, Genética y Metabolismo, Universidad de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Farmacia y Bioquímica, Hospital de Clínicas "José de San Martín", Buenos Aires, Argentina
| | - Luis Ariel Billordo
- Instituto de Inmunología, Genética y Metabolismo, Universidad de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Farmacia y Bioquímica, Hospital de Clínicas "José de San Martín", Buenos Aires, Argentina
| | - Beatriz Ameigeiras
- Unidad de Gastroenterología, Hospital General de Agudos "JM Ramos Mejía", Buenos Aires, Argentina
| | - Daniel Poncino
- Sección Hepatología, Servicio de Gastroenterología, Sanatorio Dr. "Julio Méndez", Buenos Aires, Argentina
| | - Javier Benavides
- Sección Hepatología, Servicio de Gastroenterología, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Luis Colombato
- Sección Hepatología, Servicio de Gastroenterología, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Alejandra Claudia Cherñavsky
- Instituto de Inmunología, Genética y Metabolismo, Universidad de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Farmacia y Bioquímica, Hospital de Clínicas "José de San Martín", Buenos Aires, Argentina
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Inzaugarat ME, De Matteo E, Baz P, Lucero D, García CC, Gonzalez Ballerga E, Daruich J, Sorda JA, Wald MR, Cherñavsky AC. New evidence for the therapeutic potential of curcumin to treat nonalcoholic fatty liver disease in humans. PLoS One 2017; 12:e0172900. [PMID: 28257515 PMCID: PMC5336246 DOI: 10.1371/journal.pone.0172900] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 02/10/2017] [Indexed: 02/06/2023] Open
Abstract
Introduction The immune system acts on different metabolic tissues that are implicated in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Leptin and linoleic acid have the ability to potentially affect immune cells, whereas curcumin is a known natural polyphenol with antioxidant and anti-inflammatory properties. Aims This study was designed to evaluate the pro-inflammatory and pro-oxidant effects of leptin and linoleic acid on immune cells from patients with NAFLD and to corroborate the modulatory effects of curcumin and its preventive properties against the progression of NAFLD using a high-fat diet (HFD)-induced NAFLD/nonalcoholic steatohepatitis mouse model. Results The ex vivo experiments showed that linoleic acid increased the production of reactive oxygen species in monocytes and liver macrophages, whereas leptin enhanced tumor necrosis factor-α (TNF-α) production in monocytes and interferon-γ production in circulating CD4+ cells. Conversely, oral administration of curcumin prevented HFD-induced liver injury, metabolic alterations, intrahepatic CD4+ cell accumulation and the linoleic acid- and leptin- induced pro-inflammatory and pro-oxidant effects on mouse liver macrophages. Conclusion Our findings provide new evidence for the therapeutic potential of curcumin to treat human NAFLD. However, the development of a preventive treatment targeting human circulating monocytes and liver macrophages as well as peripheral and hepatic CD4+ cells requires additional research.
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Affiliation(s)
- María Eugenia Inzaugarat
- Instituto de Inmunología, Genética y Metabolismo-CONICET- Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Elena De Matteo
- Hospital de Niños “Dr. R. Gutiérrez”, Servicio de Patología, Buenos Aires, Argentina
| | - Placida Baz
- Instituto de Inmunología, Genética y Metabolismo-CONICET- Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Diego Lucero
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica - Departamento de Bioquímica Clínica, Laboratorio de Lípidos y Arterioesclerosis, Buenos Aires, Argentina
| | - Cecilia Claudia García
- Instituto de Inmunología, Genética y Metabolismo-CONICET- Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Esteban Gonzalez Ballerga
- Universidad de Buenos Aires, Hospital de Clínicas "José de San Martin"- División de Gastroenterología, Buenos Aires, Argentina
| | - Jorge Daruich
- Universidad de Buenos Aires, Hospital de Clínicas "José de San Martin"- División de Gastroenterología, Buenos Aires, Argentina
| | - Juan Antonio Sorda
- Universidad de Buenos Aires, Hospital de Clínicas "José de San Martin"- División de Gastroenterología, Buenos Aires, Argentina
| | - Miriam Ruth Wald
- Instituto de Investigaciones Biomédicas (BIOMED)- Universidad católica Argentina-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Alejandra Claudia Cherñavsky
- Instituto de Inmunología, Genética y Metabolismo-CONICET- Universidad de Buenos Aires, Buenos Aires, Argentina
- * E-mail:
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Inzaugarat ME, Billordo LA, Vodánovich F, Cervini GM, Casavalle PL, Vedire C, Cherñavsky AC. Alterations in innate and adaptive immune leukocytes are involved in paediatric obesity. Pediatr Obes 2014; 9:381-90. [PMID: 23852831 DOI: 10.1111/j.2047-6310.2013.00179.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 03/26/2013] [Accepted: 04/12/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND Adipose tissue is the main source of the cytokines and adipokines that are increased in the context of obesity. The production of reactive oxygen species (ROS) and cytokines by circulating immune cells can be regulated by these pro-inflammatory factors even before infiltration into adipose tissue. OBJECTIVE To investigate the alterations that can occur in circulating monocytes and lymphocytes in paediatric obesity. METHODS In this study, 54 paediatric obese patients and 30 age-matched metabolically healthy individuals were enrolled. Intracellular cytokines were analyzed after phorbol myristate acetate (PMA) or leptin plus PMA stimulation of lymphocytes and monocytes by flow cytometry. ROS generation was measured using dichlorofluorescein-diacetate. Both a 'stimulation index' and a 'fold of increase' were calculated for statistical purposes. RESULTS Both interferon gamma (IFN-γ) production by circulating CD4+ and CD8+ lymphocytes and ROS production by monocytes following PMA stimulation were increased in obese patients. Leptin induced an increased production of IFN-γ in both subsets of T cells and tumour necrosis factor alpha in monocytes, and linoleic acid induced a higher ROS production in monocytes. CONCLUSIONS The distinct functional responses of circulating cells suggest that alterations in both innate and adaptive immune cells are involved in the maintenance of low-grade inflammation in paediatric obesity.
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Affiliation(s)
- M E Inzaugarat
- Instituto de Inmunología, Genética y Metabolismo, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
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Periolo N, Guillén L, Arruvito ML, Alegre NS, Niveloni SI, Hwang JH, Bai JC, Cherñavsky AC. IL-15 controls T cell functions through its influence on CD30 and OX40 antigens in Celiac Disease. Cytokine 2014; 67:44-51. [PMID: 24680481 DOI: 10.1016/j.cyto.2014.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 12/09/2013] [Accepted: 01/11/2014] [Indexed: 01/19/2023]
Abstract
AIM To evaluate the ability of interleukin (IL)-15 to control T cell functions through its influence on CD30 and OX40 expressing cells in Celiac Disease (CD). In peripheral blood (PB), by examining the expression of OX40 in conventional effectors cells and T cells with a phenotypic specialization of regulatory cells [CD4+CD25high forkhead box protein 3 (Foxp3)+], and the co stimulation of IFN-γ and IL-4 production within CD30 and OX40 positive subsets of T cells. At the duodenal mucosa, by assessing the expression of CD30 and OX40 in intraepithelial (IE) and lamina propria (LP) lymphocytes (IEL, LPL). PATIENTS AND METHODS PB and duodenal mucosal biopsies were obtained from 38 patients with classic CD (Cel) and 38 healthy controls (HC). Analysis of cell surface and/or intracellular antigens was performed in anti-CD3-treated PB mononuclear cells (PBMC) before and after treatment with recombinant IL-15 (rIL-15), and in IE and LP cellular suspensions prepared from duodenal biopsies pre-treated with/without rIL-15. RESULTS A subpopulation of CD3+OX40+ T blasts was induced in Cel and HC by a 3days treatment of PBMC with anti-CD3 and decreased its size thereafter, regardless of the presence of rIL-15. However, the addition of rIL-15 to T blasts distinctively induced the survival of T cells with a regulatory phenotype that expresses OX40 antigen in Cel (p<0.05). Celiac patients showed higher frequencies of IFN-γ-producing CD3+CD30+ blasts before and after treatment with rIL-15 (p<0.05, vs. HC). IL-15 increased the frequencies of CD3+CD30+ LPL (HC: p<0.05, Cel: p<0.05) but not of CD3+OX40+ LPL, and CD30 or OX40 positive IEL. CONCLUSIONS The distinctive control of OX40+ cells with a T regulatory phenotype mediated by the influence of IL-15 comes out as new function of this cytokine in the context of CD. The higher production of IFN-γ by a subpopulation of peripheral CD3+CD30+ cells contributes to the type I biased immune response.
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Affiliation(s)
- N Periolo
- Instituto de Inmunología, Genética y Metabolismo, Hospital de Clínicas "José de San Martín", Universidad de Buenos Aires, Buenos Aires, Argentina
| | - L Guillén
- Instituto de Inmunología, Genética y Metabolismo, Hospital de Clínicas "José de San Martín", Universidad de Buenos Aires, Buenos Aires, Argentina
| | - M L Arruvito
- Instituto de Inmunología, Genética y Metabolismo, Hospital de Clínicas "José de San Martín", Universidad de Buenos Aires, Buenos Aires, Argentina
| | - N S Alegre
- Instituto de Inmunología, Genética y Metabolismo, Hospital de Clínicas "José de San Martín", Universidad de Buenos Aires, Buenos Aires, Argentina
| | - S I Niveloni
- Sección Intestino Delgado, Departamento de Medicina, Hospital de Gastroenterología "Dr. Carlos Bonorino Udaondo", Buenos Aires, Argentina
| | - J H Hwang
- Sección Intestino Delgado, Departamento de Medicina, Hospital de Gastroenterología "Dr. Carlos Bonorino Udaondo", Buenos Aires, Argentina
| | - J C Bai
- Sección Intestino Delgado, Departamento de Medicina, Hospital de Gastroenterología "Dr. Carlos Bonorino Udaondo", Buenos Aires, Argentina
| | - A C Cherñavsky
- Instituto de Inmunología, Genética y Metabolismo, Hospital de Clínicas "José de San Martín", Universidad de Buenos Aires, Buenos Aires, Argentina.
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Cherñavsky AC, Páez MC, Periolo N, Correa P, Guillén L, Niveloni SI, Mauriño E, Bai JC, Anaya JM. The simultaneous presence of IL-1B and TNFA two-positions risk haplotypes enhances the susceptibility for celiac disease. Cytokine 2008; 42:48-54. [PMID: 18346907 DOI: 10.1016/j.cyto.2008.01.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2007] [Revised: 12/18/2007] [Accepted: 01/30/2008] [Indexed: 11/24/2022]
Abstract
To assess the joint contribution of interleukin 1 beta (IL-1B) and tumor necrosis factor alpha (TNFalpha) to the genetic risk of developing celiac disease (CD), we analyzed four biallelic polymorphisms of TNFA and IL-1B genes in 228 patients and 244 healthy controls. The individual contribution of TNFA -308A and IL-1B -511C alleles was weak (OR 1.47 and 1.66, respectively) and was null for TNFA -238 A/G and IL-1B +3953 C/T single nucleotide polymorphisms (SNPs). Due to the potential linkage disequilibrium between TNFA, human leukocyte antigen (HLA) -DQA1 and HLA-DQB1 genes, only individuals carrying DQ2 antigen (DQ2-positive) were considered to perform haplotype analyses. Two-position risk haplotypes were first defined by the combined presence of -511C and +3953T alleles for IL-1B (OR 9.402) or -308A and -238A alleles for TNFA (OR 15.389). The TNFA/IL-1B combined haplotype-stratified association analysis showed that the simultaneous presence of TNFA risk and IL-1B non-risk haplotypes (OR 13.32) but not TNFA non-risk and IL-1B risk haplotypes (OR 0.71) is associated with CD. Interestingly, our data suggest that the coexistence of both risk haplotypes seems to work synergistically (OR 29.59), which enhances the risk of developing CD.
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Affiliation(s)
- Alejandra Claudia Cherñavsky
- Immunogenetic Laboratory, Hospital de Clínicas José de San Martín, Universidad de Buenos Aires, Av. Cordoba 2351, 1120 Buenos Aires, Argentina.
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De Biasio MB, Periolo N, Avagnina A, García de Dávila MT, Ciocca M, Goñi J, de Matteo E, Galoppo C, Cañero-Velasco MC, Fainboim H, Muñoz AE, Fainboim L, Cherñavsky AC. Liver infiltrating mononuclear cells in children with type 1 autoimmune hepatitis. J Clin Pathol 2006; 59:417-23. [PMID: 16489183 PMCID: PMC1860380 DOI: 10.1136/jcp.2005.028613] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/07/2005] [Indexed: 12/30/2022]
Abstract
OBJECTIVE To investigate infiltrating cells in the liver of children with type 1 autoimmune hepatitis (AH-1). METHODS liver biopsies from 24 untreated AH-1 patients (14 children, 10 adults), five patients with hepatitis C virus related chronic hepatitis (HCV), and 10 control liver specimens (CL) were processed for immunohistochemical cell characterisation. RESULTS Two different cell distribution patterns were detected in the liver of patients with AH-1: (1) CD4(+) and CD20(+) cells were found in the central areas of the portal tracts (portal distribution); (2) CD8(+) cells were observed at the periphery of the portal space (periportal distribution). Some cell subsets, like CD56, CD57, Fas-L, and Bak, showed a non-defined distribution pattern. The presence of two well defined patterns of cell distribution was not observed in HCV and CL (CD4(+), CD20(+), and CD8(+) cells were uniformly distributed in the portal space). In AH-1 and CL, the NK markers CD56 and CD57 were found scattered throughout the liver parenchyma. However, in HCV biopsies, CD56(+) cells were also clearly increased in both the portal and the periportal areas. Biopsies of AH-1 and HCV patients showed a uniform distribution of Fas-L and Bak in the portal and periportal areas, with Bak staining also detected in the hepatic parenchyma. CONCLUSIONS Despite clinical and genetic differences, there was a similar distribution of liver infiltrating mononuclear cells in children and adults with AH-1. These results raise the possibility of reclassifying cryptogenic chronic hepatitis by immunohistochemical analysis of infiltrating liver cells.
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Affiliation(s)
- M B De Biasio
- División inmunogenética, Hospital de Clínicas José de San Martín, Universidad de Buenos Aires, Buenos Aires, Argentina
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Cherñavsky AC, Paladino N, Rubio AE, De Biasio MB, Periolo N, Cuarterolo M, Goñi J, Galoppo C, Cañero-Velasco MC, Muñoz AE, Fainboim H, Fainboim L. Simultaneous expression of th1 cytokines and IL-4 confers severe characteristics to type I autoimmune hepatitis in children. Hum Immunol 2004; 65:683-91. [PMID: 15301856 DOI: 10.1016/j.humimm.2004.03.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2003] [Revised: 03/25/2004] [Accepted: 03/25/2004] [Indexed: 01/30/2023]
Abstract
To investigate the immunopathogenic mechanisms of type I autoimmune hepatitis in children, we analyzed by quantitative or semiquantitative reverse transcription-polymerase chain reaction the expression of cytokines interferon (IFN)-gamma, interleukin (IL)-12p40, IL-18, IL-4, IL-10, and IL-12R beta 2. In addition, liver and peripheral blood was collected to investigate the expression of the natural killer T (NKT) cell marker V alpha 24. The presence of NKT cells in hepatic lesions were also identified by immunohistochemistry. The analysis was performed on liver biopsies from 25 children with type I autoimmune hepatitis. As disease controls, we included six children with hepatitis C virus-related chronic hepatitis and nine control livers. The expression of IFN-gamma and IL-12p40 was not detected in controls but was clearly upregulated in pathologic biopsies. In addition, these samples showed an increased expression of IL-18 (p = 0.0003), IL-4 (p = 0.0055), and IL-12R beta 2 (p = 0.007). Western blot analysis confirmed the expression of IL-12p40 and IL-18. However, for IL-18, we detected only the immature biologically inactive polypeptide. The V alpha 24 transcripts were found increased in the liver (p = 0.0007) where V alpha 24(+) cells were also localized, but decreased in peripheral blood mononuclear cells (p = 0.041). In addition to a type I immune response, NKT cells might play a substantial role in the pathogenesis of type I autoimmune hepatitis in children.
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MESH Headings
- Adolescent
- Autoantibodies/blood
- Biopsy, Needle
- Blood Chemical Analysis
- Blotting, Western
- Child
- Cytokines/genetics
- Cytokines/immunology
- Cytokines/metabolism
- Female
- Gene Expression
- Hepatitis, Autoimmune/genetics
- Hepatitis, Autoimmune/immunology
- Hepatitis, Autoimmune/pathology
- Humans
- Immunohistochemistry
- Interferon-gamma/genetics
- Interleukin-10/genetics
- Interleukin-10/metabolism
- Interleukin-12/genetics
- Interleukin-12/metabolism
- Interleukin-12 Subunit p40
- Interleukin-18/genetics
- Interleukin-18/metabolism
- Interleukin-4/genetics
- Interleukin-4/immunology
- Interleukin-4/metabolism
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Killer Cells, Natural/pathology
- Leukocytes, Mononuclear/chemistry
- Liver/immunology
- Liver/metabolism
- Liver/pathology
- Male
- Protein Subunits/genetics
- Protein Subunits/metabolism
- Receptors, Antigen, T-Cell, alpha-beta/analysis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Interleukin/genetics
- Receptors, Interleukin/metabolism
- Receptors, Interleukin-12
- T-Lymphocytes, Helper-Inducer/immunology
- T-Lymphocytes, Helper-Inducer/metabolism
- Th1 Cells/immunology
- Th1 Cells/metabolism
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Affiliation(s)
- Alejandra Claudia Cherñavsky
- División Inmunogenética, Hospital de Clínicas José de San Martín, Universidad de Buenos Aires, Av. Córdoba 2351 (1120) Buenos Aires, Argentina
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Vulcano M, Alves Rosa MF, Minnucci FS, Cherñavsky AC, Isturiz MA. N-formyl-methionyl-leucyl-phenylalanine (fMLP) inhibits tumour necrosis factor-alpha (TNF-alpha) production on lipopolysaccharide (LPS)-stimulated human neutrophils. Clin Exp Immunol 1998; 113:39-47. [PMID: 9697981 PMCID: PMC1905013 DOI: 10.1046/j.1365-2249.1998.00631.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/04/1998] [Indexed: 01/01/2023] Open
Abstract
During gram-negative infections bacterial components, such as LPS and formylated peptides, exert profound physiological effects on polymorphonuclear neutrophils (PMN) resulting in increased neutrophil effector activities, including the generation of oxidative metabolites, degranulation, phagocytosis and cytokine release. There is not enough evidence about the relationships between LPS and formylated bacterial peptides in the triggering and regulation of the immune inflammatory response. In this study, we present evidence indicating that pretreatment of human PMN with a prototype formylated peptide such as fMLP results in the inhibition of TNF-alpha secretion, a key molecule that plays a central role in the pathogenesis of septic shock. This inhibitory effect of fMLP does not appear to alter the expression of LPS receptors or the transcriptional pathway of the TNF-alpha mRNA, but instead, fMLP reduces the expression of the membrane form of TNF-alpha on the PMN surface. These findings indicate that fMLP, a typical proinflammatory agent, could play, at least in determined conditions, an anti-inflammatory role.
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Affiliation(s)
- M Vulcano
- División Immunología, Instituto de Investigaciones Hematológicas, Academia Nacional de Medicina, Buenos Aires, Argentina
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Abstract
Decreased dopaminergic and increased oestrogenic effects induce prolactin release and DNA synthesis in prolactin secreting cells of the adult male rats. Oestrogen treatment for 7 days significantly increased the levels of prolactin, c-myc and c-fos mRNAs. The effect of oestrogens was reversed by the administration of the dopaminergic agonist bromocriptine. There was an early gradual increase of c-myc mRNA levels beginning 30 min after the injection of the steroid. c-fos mRNA levels increased sharply 15 min after oestrogen administration and decreased to basal values 15 min later to remain at this level over the period of time evaluated. Administration of the dopaminergic antagonist haloperidol did not change the levels of protooncogenes mRNA. However, in rats previously treated with oestrogens for 7 days c-myc mRNA levels increased 90 min after the injection of haloperidol and decreased to basal values after 2.5 h. c-fos mRNA levels increased sharply 30 min after haloperidol administration and also decreased to basal values 1 h later. We propose that changes in protooncogenes expression may be involved in the stimulation of cell proliferation induced by prolactin secretion.
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Affiliation(s)
- A C Cherñavsky
- Fundación Centro de Investigaciones Médicas Albert Einstein, Buenos Aires, Argentina
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Abstract
Searching for differences in gene expression between different types of human pituitary adenomas, we evaluated the concentration of mRNA from hormonal genes (prolactin and growth hormone) and oncogenes (c-myc and c-fos) in 12 growth hormone-secreting 7 prolactin-secreting and 11 nonsecreting adenomas. We found a positive correlation between clinical diagnoses and hormonal gene expression in all the cases. Our reports indicate the presence of c-myc and c-fos mRNA in all the adenomas evaluated. The concentration of c-myc mRNA was higher in somatotrophic adenomas than in prolactinomas and nonsecreting adenomas whereas c-fos mRNA concentration was similar in the different types of tumours analysed. Oncogenes products, in turn, might stimulate DNA synthesis and cell proliferation and eventually lead to the formation of pituitary adenomas. This is a working hypothesis.
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Affiliation(s)
- A C Cherñavsky
- Instituto de Neurociencias, Sanatorio Güemes, Buenos Aires, Argentina
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Rosental DG, Machiavelli GA, Cherñavsky AC, Speziale NS, Burdman JA. Indomethacin inhibits the effects of oestrogen in the anterior pituitary gland of the rat. J Endocrinol 1989; 121:513-9. [PMID: 2754375 DOI: 10.1677/joe.0.1210513] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Two inhibitors of prostaglandin synthesis, indomethacin and aspirin, blocked the increase of oestrogen-binding sites in the nuclear subcellular fraction, an increase which occurs after the administration of oestradiol. Consequently the biological effects of oestrogens in the anterior pituitary gland of the rat (prolactin synthesis, concentration of progesterone-binding sites and cell proliferation) are diminished. The anterior pituitary gland synthesized prostaglandin F2 alpha (PGF2 alpha), PGE2 and PGD2 from arachidonic acid. This synthesis was blocked when indomethacin was added to the culture media. Oestrogen increased the concentration of PGE2: an increase that was partially prevented by indomethacin. Prostaglandins may have an important role on the effects of oestrogen in the anterior pituitary gland of the rat.
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Affiliation(s)
- D G Rosental
- Departamento de Endocrinología, Centro de Investigaciones Médicas Albert Einstein, Buenos Aires, Argentina
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