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Okpareke OC, Henderson W, Akkoç S, Coban B. Platinum(II), palladium(II), and nickel(II) complexes of bisthiourea ligands. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2021.120707] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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El-Wakil ES, Salem AE, Al-Ghandour AMF. Evaluation of possible prophylactic and therapeutic effect of mefloquine on experimental cryptosporidiosis in immunocompromised mice. J Parasit Dis 2020; 45:380-393. [PMID: 34295037 DOI: 10.1007/s12639-020-01315-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 11/05/2020] [Indexed: 01/18/2023] Open
Abstract
Cryptosporidiosis is an imperative global health concern. Unfortunately, Nitazoxanide (NTZ) (the nowadays drug of choice) is not effective in treatment of immunocompromised patients. We aimed to assess the possible anti-cryptosporidial prophylactic and therapeutic effects of Mefloquine (MQ) on infected immunosuppressed murine models. Mice were divided into five groups; GI: received Mefloquine (400 mg/kg/day), GII: received NTZ (100 mg/kg/bid), GIII: received a combination, half dose regimen of both drugs, GIV: infected untreated and GV: non-infected untreated. Each treated group was divided into three subgroups; Ga prophylaxis (PX), thereafter infection, Gb first and Gc second treatment doses. Assessment was done by parasitological, histopathological and serological techniques. A significant oocyst clearance was detected in all prophylactically treated groups. GIa showed 77% reduction of the mean oocyst count in stool while GIb and GIIIc showed100% oocyst clearance. Histopathologically, the ileocecal sections from GIV showed loss of brush borders with marked villous atrophy. GIa induced a moderate improvement of those pathological changes. Moreover, the villi in GIb and GIIIc retained their normal appearance with minimal inflammatory cells. Serum interferon gamma levels showed highly significant increases in GI&GIII compared to GIV while a non-significant increase was observed in GIIa only. On the contrary, serum interleukin-17 levels showed a highly significant down-regulation in all treated groups in comparison to GIV. This study proved a marvelous effect of MQ-PX on cryptosporidiosis in immunosuppressed mice and thus it could be introduced as one of the most promising re-purposed prophylactic and therapeutic anti-cryptosporidial agents.
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Affiliation(s)
- Eman S El-Wakil
- Department of Parasitology, Theodor Bilharz Research Institute, Giza, Egypt
| | - Amal E Salem
- Department of Clinical Pharmacology, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Asmaa M F Al-Ghandour
- Department of Medical Parasitology, Faculty of Medicine, Zagazig University, Zagazig, Egypt
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Ye M, Joosse ME, Liu L, Sun Y, Dong Y, Cai C, Song Z, Zhang J, Brant SR, Lazarev M, Li X. Deletion of IL-6 Exacerbates Colitis and Induces Systemic Inflammation in IL-10-Deficient Mice. J Crohns Colitis 2020; 14:831-840. [PMID: 31679013 PMCID: PMC7346894 DOI: 10.1093/ecco-jcc/jjz176] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS Interleukin 6 [IL-6] or its receptor is currently a candidate for targeted biological therapy of inflammatory bowel disease [IBD]. Thus, a comprehensive understanding of the consequences of blocking IL-6 is imperative. We investigated this by evaluating the effects of IL-6 deletion on the spontaneous colitis of IL-10-deficient mice [IL-10-/-]. METHODS IL-6/IL-10 double-deficient mice [IL-6-/-/IL-10-/-] were generated and analysed for intestinal inflammation, general phenotypes and molecular/biochemical changes in the colonic mucosa compared with wild-type and IL-10-/- mice. RESULTS Unexpectedly, the IL-6-/-/IL-10-/- mice showed more pronounced gut inflammation and earlier disease onset than IL-10-/- mice, both locally [colon and small bowel] and systemically [splenomegaly, ulcerative dermatitis, leukocytosis, neutrophilia and monocytosis]. IL-6-/-/IL-10-/- mice exhibited elevations of multiple cytokines [IL-1β, IL-4, IL-12, TNFα] and chemokines [MCP-1 and MIG], but not IFN-γ [Th1], IL-17A and IL-17G [Th17], or IL-22 [Th22]. FOXP3 and TGF-β, two key factors for regulatory T [Treg] cell differentiation, were significantly down-regulated in the colonic mucosa, but not in the thymus or mesenteric lymph nodes, of IL-6-/-/IL-10-/- mice. CTLA-4 was diminished while iNOS was up-regulated in the colonic mucosa of IL-6-/-/IL-10-/- mice. CONCLUSION In IL-10-/- mice, complete IL-6 blockade significantly aggravates gut inflammation, at least in part by suppressing Treg/CTLA-4 and promoting the IL-1β/Th2 pathway. In addition, the double mutant exhibits signs of severe systemic inflammation. Our data define a new function of IL-6 and suggest that caution should be exercised when targeting IL-6 in IBD patients, particularly those with defects in IL-10 signalling.
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Affiliation(s)
- Mei Ye
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA,Department of Gastroenterology, Zhongnan Hospital, Wuhan University, Hubei Province, China
| | - Maria E Joosse
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Ling Liu
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA,Department of Gastroenterology, West China Hospital, Sichuan University, Sichuan Province, China
| | - Yu Sun
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Ying Dong
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Changchun Cai
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Zhenmei Song
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Jennifer Zhang
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Steven R Brant
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Mark Lazarev
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Xuhang Li
- Division of Gastroenterology, Department of Medicine, Johns Hopkins Medicine, Baltimore, MD, USA,Corresponding author: Xuhang Li, PhD, Department of Medicine, Division of Gastroenterology, Johns Hopkins University School of Medicine, 720 Rutland Ave., Ross 918, Baltimore, MD 21205, USA.
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Rath NC, Liyanage R, Gupta A, Packialakshmi B, Lay JO. A method to culture chicken enterocytes and their characterization. Poult Sci 2018; 97:4040-4047. [PMID: 29917122 DOI: 10.3382/ps/pey248] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Accepted: 05/25/2018] [Indexed: 12/18/2022] Open
Abstract
Enterocytes function as both absorptive and protective components of intestine that come in close contact with a variety of enteric factors, such as dietary, microbial, and parasites, that have potential to affect the organismal health. Understanding how enterocytes interact with this complex array of factors may help improve gut health particularly in the context of poultry production where it is also linked to food safety issues. The enterocyte in vitro culture can help screen different factors and their interactions with microbiome, and potentially be utilized in the development of interventions strategies for pathogens such as antibiotic alternatives. We developed a method to culture primary chicken enterocytes and conducted their characterization using cytochemical and proteomic methods, and investigated their potential to respond to different chemical stimuli. Using selected micronutrients, microbial toxins, and metabolic modulators, we assessed their effects on the viability and morphological changes in enterocytes. We found that whereas some nutritional factors (calcitriol, retinoic acid) produced different morphological changes, toxins such as aflatoxin B1 and deoxynivalenol produced enterocyte degeneration and death, and the bacterial lipopolysaccharide had very little effect compared on the basis of their mass. Both cyclic AMP and phorbol myristate acetate exhibited some cachectic effects on enterocytes with the later showing more severe changes. Thyroxin induced distinct morphological changes making the cells more cuboidal and Na-butyrate produced no significant change in morphology. The cytochemical and proteomic characterization suggest that these enterocytes largely belong to epithelial cell categories which may be amenable to analysis of biochemical paths and mechanisms of action of different factors that affect these cells. Based on these results we conclude that chicken enterocyte culture can be a useful in vitro model to study intestinal physiology.
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Affiliation(s)
- Narayan C Rath
- USDA/Agricultural Research Service, University of Arkansas, Fayetteville, AR 72701, USA
| | - Rohana Liyanage
- Statewide Mass spectrometry Facility, Department of Chemistry Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
| | - Anamika Gupta
- The Department of Poultry Science, Poultry Science Center, University of Arkansas, Fayetteville, AR 72701, USA
| | - Balamurugan Packialakshmi
- USDA/Agricultural Research Service, University of Arkansas, Fayetteville, AR 72701, USA.,The Department of Poultry Science, Poultry Science Center, University of Arkansas, Fayetteville, AR 72701, USA
| | - Jackson O Lay
- Statewide Mass spectrometry Facility, Department of Chemistry Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
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Pysz MA, Hao F, Hizli AA, Lum MA, Swetzig WM, Black AR, Black JD. Differential regulation of cyclin D1 expression by protein kinase C α and ϵ signaling in intestinal epithelial cells. J Biol Chem 2014; 289:22268-83. [PMID: 24914206 DOI: 10.1074/jbc.m114.571554] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Cellular accumulation of cyclin D1, a key regulator of cell proliferation and tumorigenesis, is subject to tight control. Our previous studies have identified PKCα as a negative regulator of cyclin D1 in the intestinal epithelium. However, treatment of non-transformed IEC-18 ileal crypt cells with PKC agonists has a biphasic effect on cyclin D1 expression. Initial PKCα-mediated down-regulation is followed by recovery and subsequent accumulation of the cyclin to levels markedly higher than those seen in untreated cells. Using protein overexpression strategies, siRNA, and pharmacological inhibitors, we now demonstrate that the recovery and hyperinduction of cyclin D1 reflect the combined effects of (a) loss of negative signals from PKCα due to agonist-induced PKCα down-regulation and (b) positive effects of PKCϵ. PKCϵ-mediated up-regulation of cyclin D1 requires sustained ERK stimulation and transcriptional activation of the proximal cyclin D1 (CCDN1) promoter, without apparent involvement of changes in protein stability or translation. PKCϵ also up-regulates cyclin D1 expression in colon cancer cells, through mechanisms that parallel those in IEC-18 cells. Although induction of cyclin D1 by PKCϵ is dependent on non-canonical NF-κB activation, the NF-κB site in the proximal promoter is not required. Instead, cyclin D1 promoter activity is regulated by a novel interaction between NF-κB and factors that associate with the cyclic AMP-response element adjacent to the NF-κB site. The differential effects of PKCα and PKCϵ on cyclin D1 accumulation are likely to contribute to the opposing tumor-suppressive and tumor-promoting activities of these PKC family members in the intestinal epithelium.
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Affiliation(s)
- Marybeth A Pysz
- the Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Fang Hao
- the Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - A Asli Hizli
- the Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Michelle A Lum
- From the Eppley Institute for Research in Cancer and Allied Diseases and the Fred and Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, Nebraska 68198 and
| | - Wendy M Swetzig
- the Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Adrian R Black
- the Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263From the Eppley Institute for Research in Cancer and Allied Diseases and the Fred and Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, Nebraska 68198 and
| | - Jennifer D Black
- the Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263From the Eppley Institute for Research in Cancer and Allied Diseases and the Fred and Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, Nebraska 68198 and
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Hammami I, Chen J, Murschel F, Bronte V, De Crescenzo G, Jolicoeur M. Immunosuppressive activity enhances central carbon metabolism and bioenergetics in myeloid-derived suppressor cells in vitro models. BMC Cell Biol 2012; 13:18. [PMID: 22762146 PMCID: PMC3433355 DOI: 10.1186/1471-2121-13-18] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 07/04/2012] [Indexed: 01/10/2023] Open
Abstract
Background The tumor microenvironment contains a vast array of pro- and anti-inflammatory cytokines that alter myelopoiesis and lead to the maturation of immunosuppressive cells known as myeloid-derived suppressor cells (MDSCs). Incubating bone marrow (BM) precursors with a combination of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-6 (IL-6) generated a tumor-infiltrating MDSC-like population that impaired anti-tumor specific T-cell functions. This in vitro experimental approach was used to simulate MDSC maturation, and the cellular metabolic response was then monitored. A complementary experimental model that inhibited L-arginine (L-Arg) metabolizing enzymes in MSC-1 cells, an immortalized cell line derived from primary MDSCs, was used to study the metabolic events related to immunosuppression. Results Exposure of BM cells to GM-CSF and IL-6 activated, within 24 h, L-Arg metabolizing enzymes which are responsible for the MDSCs immunosuppressive potential. This was accompanied by an increased uptake of L-glutamine (L-Gln) and glucose, the latter being metabolized by anaerobic glycolysis. The up-regulation of nutrient uptake lead to the accumulation of TCA cycle intermediates and lactate as well as the endogenous synthesis of L-Arg and the production of energy-rich nucleotides. Moreover, inhibition of L-Arg metabolism in MSC-1 cells down-regulated central carbon metabolism activity, including glycolysis, glutaminolysis and TCA cycle activity, and led to a deterioration of cell bioenergetic status. The simultaneous increase of cell specific concentrations of ATP and a decrease in ATP-to-ADP ratio in BM-derived MDSCs suggested cells were metabolically active during maturation. Moreover, AMP-activated protein kinase (AMPK) was activated during MDSC maturation in GM-CSF and IL-6–treated cultures, as revealed by the continuous increase of AMP-to-ATP ratios and the phosphorylation of AMPK. Likewise, AMPK activity was decreased in MSC-1 cells when L-Arg metabolizing enzymes were inhibited. Finally, inhibition of AMPK activity by the specific inhibitor Compound C (Comp-C) resulted in the inhibition of L-Arg metabolizing enzyme activity and abolished MDSCs immunosuppressive activity. Conclusions We anticipate that the inhibition of AMPK and the control of metabolic fluxes may be considered as a novel therapeutic target for the recovery of the immunosurveillance process in cancer-bearing hosts.
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Affiliation(s)
- Ines Hammami
- Department of Chemical Engineering, Ecole Polytechnique de Montréal, 2500 Chemin de Polytechnique, H3T-1J4, Montreal, QC, Canada
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Gerlo S, Kooijman R, Beck IM, Kolmus K, Spooren A, Haegeman G. Cyclic AMP: a selective modulator of NF-κB action. Cell Mol Life Sci 2011; 68:3823-41. [PMID: 21744067 PMCID: PMC11114830 DOI: 10.1007/s00018-011-0757-8] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 06/10/2011] [Accepted: 06/16/2011] [Indexed: 10/18/2022]
Abstract
It has been known for several decades that cyclic AMP (cAMP), a prototypical second messenger, transducing the action of a variety of G-protein-coupled receptor ligands, has potent immunosuppressive and anti-inflammatory actions. These actions have been attributed in part to the ability of cAMP-induced signals to interfere with the function of the proinflammatory transcription factor Nuclear Factor-kappaB (NF-κB). NF-κB plays a crucial role in switching on the gene expression of a plethora of inflammatory and immune mediators, and as such is one of the master regulators of the immune response and a key target for anti-inflammatory drug design. A number of fundamental molecular mechanisms, contributing to the overall inhibitory actions of cAMP on NF-κB function, are well established. Paradoxically, recent reports indicate that cAMP, via its main effector, the protein kinase A (PKA), also promotes NF-κB activity. Indeed, cAMP actions appear to be highly cell type- and context-dependent. Importantly, several novel players in the cAMP/NF-κB connection, which selectively direct cAMP action, have been recently identified. These findings not only open up exciting new research avenues but also reveal novel opportunities for the design of more selective, NF-κB-targeting, anti-inflammatory drugs.
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Affiliation(s)
- Sarah Gerlo
- VIB Department of Medical Protein Research, Ghent University (UGent), Albert Baertsoenkaai, Belgium.
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8
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Mühl H, Bachmann M, Pfeilschifter J. Inducible NO synthase and antibacterial host defence in times of Th17/Th22/T22 immunity. Cell Microbiol 2011; 13:340-8. [PMID: 21199257 DOI: 10.1111/j.1462-5822.2010.01559.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
During the last two decades nitric oxide (NO) produced by inducible NO synthase (iNOS or NOS2) has been characterized as immunoregulatory and antimicrobial principle displaying the potential to determine course of disease in a range of infections. Being an enzyme primarily regulated on expressional level, cytokine-driven iNOS appears to be connected in particular with activation of Th1-type immunity. However, with the recent advent of additional, partly overlapping CD4(+) T cell effector subsets, namely Th17 and Th22 cells, a further layer of complexity has been added to immunoregulatory networks determining inflammatory gene expression in the context of microbial infections. Here, we review current knowledge on activation of iNOS function by interleukin (IL)-17 and IL-22 with focus on Th17/Th22-directed antibacterial immunity.
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Affiliation(s)
- Heiko Mühl
- Pharmazentrum frankfurt/ZAFES, University Hospital Goethe-University, Frankfurt am Main, Germany.
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9
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Keklikoglu N, Koray M, Kocaelli H, Akinci S. iNOS expression in oral and gastrointestinal tract mucosa. Dig Dis Sci 2008; 53:1437-42. [PMID: 17987386 DOI: 10.1007/s10620-007-0061-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2006] [Accepted: 09/27/2007] [Indexed: 12/16/2022]
Abstract
It is known that the overproduction of nitric oxide (NO) by nitric oxide synthase (NOS) occurs during the progression of various inflammatory diseases in intestinal tract. NOS inhibitors or inducible nitric oxide synthase (iNOS) gene expression inhibitors should be considered as potential anti-inflammatory agents, as NO synthesized by iNOS is related to various pathophysiological processes including inflammation. In order to understand the relationship between iNOS and pathological reactions such as the inflammatory process and malign transformation clearly, the existence and amount of constitutive expression should be determined. It is crucial to comprehend the harmful and protective amounts of iNOS expressions in order to clarify the relationship between iNOS and pathological processes. Evidently, only after this inspection is it possible to utilize iNOS as a marker and treatment instrument during the diagnosis and treatment of malign transformation and the inflammatory process.
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Affiliation(s)
- Nurullah Keklikoglu
- Faculty of Dentistry, Department of Histology and Embryology, Istanbul University, Capa, Istanbul, Turkey.
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de Vries EFJ, Vroegh J, Dijkstra G, Moshage H, Elsinga PH, Jansen PLM, Vaalburg W. Synthesis and evaluation of a fluorine-18 labeled antisense oligonucleotide as a potential PET tracer for iNOS mRNA expression. Nucl Med Biol 2004; 31:605-12. [PMID: 15219279 DOI: 10.1016/j.nucmedbio.2004.02.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Inducible NO synthase (iNOS) is overexpressed in inflammatory bowel diseases. An antisense oligonucleotide with good hybridization properties for iNOS mRNA was selected using RT-PCR. The oligonucleotide was reliably labeled with fluorine-18 using N-(4-[(18)F]fluorobenzyl)-2-bromoacetamide. Cellular uptake and efflux of oligonucleotide complexed with FuGENE-6 were rapid, unlike naked oligonucleotide, which hardly accumulated. However, neither uptake nor efflux showed any selectivity for iNOS expressing cells. The oligonucleotide showed a high level of non-specific binding, which may have obscured its specific hybridization to iNOS mRNA.
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Affiliation(s)
- Erik F J de Vries
- PET Center, Groningen University Hospital, P.O. Box 30.001, 9700 RB Groningen, The Netherlands.
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Effects of baicalin on expression of inducible nitric oxide synthase in cultured fibroblasts stimulated by cytokines. Chin J Integr Med 2004. [DOI: 10.1007/bf02836558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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12
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Koschorreck S, Wenzel F, Fuhrmann M, Racké K. Effects of phosphodiesterase inhibitors on L-arginine pathways in rat alveolar macrophages. Eur J Pharmacol 2003; 471:229-36. [PMID: 12826243 DOI: 10.1016/s0014-2999(03)01830-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Effects of phosphodiesterase inhibitors on L-arginine-dependent pathways in rat alveolar macrophages, inducible nitric oxide (NO) synthase (iNOS) and arginase, were studied. Culture of rat alveolar macrophages in the presence of lipopolysaccharides (20 h) caused an increase of arginase activity (by 135%) and nitrite concentration (fourfold). The nonselective phosphodiesterase inhibitor IBMX (2-isobutyl-1-methylxanthine) enhanced arginase activity by 35% and nitrite accumulation by 130%. IBMX caused a clear increase in iNOS protein levels and a relatively smaller increase in iNOS mRNA. The effect of IBMX on nitrite accumulation was largely attenuated by the protein kinase A inhibitor K 5720. The phosphodiesterase 4 inhibitor rolipram enhanced nitrite accumulation more effectively than the phosphodiesterase 3 inhibitor siguadozan (about 50% and 20% of IBMX effect, respectively), whereas the phosphodiesterase 3/4 inhibitor benzafendrine was as effective as IBMX. In conclusion, in rat alveolar macrophages, phosphodiesterase 4 and, to a smaller extent, phosphodiesterase 3 play a role in the control of iNOS-mediated NO synthesis.
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Affiliation(s)
- Sahra Koschorreck
- Institute of Pharmacology and Toxicology, University of Bonn, Reuterstr. 2b, D-53113 Bonn, Federal Republic of Germany
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Cytokines, Chemokines and Growth Factors in the Pathogenesis and Treatment of Inflammatory Bowel Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003. [DOI: 10.1007/978-1-4615-0171-8_15] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Jonassen TEN, Graebe M, Promeneur D, Nielsen S, Christensen S, Olsen NV. Lipopolysaccharide-induced acute renal failure in conscious rats: effects of specific phosphodiesterase type 3 and 4 inhibition. J Pharmacol Exp Ther 2002; 303:364-74. [PMID: 12235272 DOI: 10.1124/jpet.102.036194] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In conscious, chronically instrumented rats we examined 1) renal tubular functional changes involved in lipopolysaccharide (LPS)-induced acute renal failure; 2) the effects of LPS on the expression of selected renal tubular water and sodium transporters; and 3) effects of milrinone, a phosphodiesterase type 3 (PDE3) inhibitor, and Ro-20-1724, a PDE4 inhibitor, on LPS-induced changes in renal function. Intravenous infusion of LPS (4 mg/kg b.wt. over 1 h) caused an immediate decrease in glomerular filtration rate (GFR) and proximal tubular outflow without changes in mean arterial pressure (MAP). LPS-induced fall in GFR and proximal tubular outflow were sustained on day 2. Furthermore, LPS-treated rats showed a marked increase in fractional distal water excretion, despite significantly elevated levels of plasma vasopressin (AVP). Semiquantitative immunoblotting showed that LPS increased the expression of the Na(+),K(+),2Cl(-)-cotransporter (BSC1) in the thick ascending limb, whereas the expression of the AVP-regulated water channel aquaporin-2 in the collecting duct (CD) was unchanged. Pretreatment with milrinone or Ro-20-1724 enhanced LPS-induced increases in plasma tumor necrosis factor-alpha and lactate, inhibited the LPS-induced tachycardia, and exacerbated the acute LPS-induced fall in GFR. Furthermore, Ro-20-1724-treated rats were unable to maintain MAP. We conclude 1) PDE3 or PDE4 inhibition exacerbates LPS-induced renal failure in conscious rats; and 2) LPS treated rats develop an escape from AVP in the CDs, which could be aimed to protect against water intoxication in septic conditions associated with decreased GFR and high levels of AVP.
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Affiliation(s)
- Thomas E N Jonassen
- Department of Pharmacology, The Panum Institute, University of Copenhagen, Denmark.
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Sasahara Y, Mutoh M, Takahashi M, Fukuda K, Tanaka N, Sugimura T, Wakabayashi K. Suppression of promoter-dependent transcriptional activity of inducible nitric oxide synthase by sodium butyrate in colon cancer cells. Cancer Lett 2002; 177:155-61. [PMID: 11825662 DOI: 10.1016/s0304-3835(01)00778-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Butyrate suppresses the growth of colon cancer cells, inducing differentiation and apoptosis in vitro. Increased expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) has been suggested to be closely involved in colon carcinogenesis. In this study, effects of sodium butyrate on the promoter-dependent transcriptional activity of iNOS and COX-2 genes were investigated in a colon cancer cell line, DLD-1, using a reporter gene assay system. Sodium butyrate significantly reduced promoter-dependent iNOS transcriptional activity dose-dependently at concentrations higher than 0.1 mM. COX-2 transcriptional activity was not suppressed, but slightly increased. While hyperacetylated histones appeared at concentrations of sodium butyrate suppressing iNOS gene promoter activity, promoter-dependent transcriptional activities of iNOS and COX-2 genes were both increased by the histone deacetylase inhibitor trichostatin A. These results suggested that sodium butyrate exhibits differential effects on iNOS and COX-2 genes, acting to suppress iNOS expression via mechanisms independent of histone acetylation.
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Affiliation(s)
- Yasuyoshi Sasahara
- Cancer Prevention Division, National Cancer Center Research Institute, 1-1 Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045, Japan
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Pollok RC, Farthing MJ, Bajaj-Elliott M, Sanderson IR, McDonald V. Interferon gamma induces enterocyte resistance against infection by the intracellular pathogen Cryptosporidium parvum. Gastroenterology 2001; 120:99-107. [PMID: 11208718 DOI: 10.1053/gast.2001.20907] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND & AIMS Interferon (IFN)-gamma plays an important role in the immunologic control of infection by the protozoan enteropathogen Cryptosporidium parvum. We tested the hypothesis that IFN-gamma may directly inhibit infection of enterocytes by this pathogen. METHODS HT-29, Caco-2, and H4 human enterocyte cell lines were grown in monolayers and incubated with IFN-gamma before exposure with C. parvum. IFN-gamma receptor expression in the cell lines was determined by Western blot analysis. RESULTS IFN-gamma inhibited C. parvum infection of both HT-29 and Caco-2 cells but not H4 cells. Response to IFN-gamma was related to the expression of the IFN-gamma receptor in the respective cell lines. The effect of IFN-gamma was partially reversed by inhibition of the JAK/STAT signaling pathway. IFN-gamma mediated its action by at least 2 mechanisms: (1) inhibition of parasite invasion and (2) by modification of intracellular Fe(2+) concentration. No role for tryptophan starvation or nitric oxide synthase activity was found. TNF-alpha and IL-1beta also had anti-C. parvum activity but had no synergistic effect with IFN-gamma. CONCLUSIONS IFN-gamma directly induces enterocyte resistance against C. parvum infection; this observation may have important consequences for our understanding of the mucosal immune response to invasive pathogens.
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Affiliation(s)
- R C Pollok
- Digestive Diseases Research Centre, St. Bartholomew's and The Royal London School of Medicine and Dentistry, London, England.
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Cavicchi M, Gibbs L, Whittle BJ. Inhibition of inducible nitric oxide synthase in the human intestinal epithelial cell line, DLD-1, by the inducers of heme oxygenase 1, bismuth salts, heme, and nitric oxide donors. Gut 2000; 47:771-8. [PMID: 11076874 PMCID: PMC1728135 DOI: 10.1136/gut.47.6.771] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND The inducible isoform of nitric oxide synthase (iNOS) may be involved in the mucosal injury associated with inflammatory bowel disease (IBD). In contrast with iNOS, the inducible heme oxygenase 1 (HO-1) is considered to act as a protective antioxidant system. AIMS To evaluate the effects of the known HO-1 inducers, cadmium and bismuth salts, heme, and nitric oxide (NO) donors, on iNOS activity, and expression in the human intestinal epithelial cell line DLD-1. METHODS iNOS activity was assessed by the Griess reaction and the radiochemical L-arginine conversion assay. iNOS mRNA and iNOS protein expression were determined by northern and western blotting, respectively. RESULTS Cytokine exposure led to induction of iNOS activity, iNOS mRNA, and iNOS protein expression. Preincubation of DLD-1 cells with heme (1-50 microM) inhibited cytokine induced iNOS activity in a concentration dependent manner. This inhibitory effect was abolished by the HO-1 specific inhibitor tin protoporphyrin. Preincubation with NO donors sodium nitroprusside (SNP 1-1000 microM) or S-nitroso-acetyl-penicillamine (SNAP 1-1000 microM), or with the heavy metals cadmium chloride (10-40 microM), bismuth citrate, or ranitidine bismuth citrate (10-3000 microM) inhibited iNOS activity in a concentration dependent manner. Moreover, SNP and heme abolished cytokine induced iNOS protein as well as iNOS mRNA expression, whereas cadmium chloride did not modify iNOS protein expression. CONCLUSIONS Heme, the heavy metals cadmium and bismuth, as well as NO donors, are potent inhibitors of cytokine induced iNOS activity. Heme and NO donors act at the transcriptional level inhibiting iNOS mRNA expression. Such findings suggest the potential for interplay between the iNOS and HO-1 systems, which may modulate the progress of IBD.
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Affiliation(s)
- M Cavicchi
- William Harvey Research Institute, St Bartholomew's and the Royal London School of Medicine and Dentistry, Charterhouse Square, London EC1M 6BQ, UK
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18
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Mühl H, Chang JH, Huwiler A, Bosmann M, Paulukat J, Ninic R, Nold M, Hellmuth M, Pfeilschifter J. Nitric oxide augments release of chemokines from monocytic U937 cells: modulation by anti-inflammatory pathways. Free Radic Biol Med 2000; 29:969-80. [PMID: 11084285 DOI: 10.1016/s0891-5849(00)00389-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitric oxide (NO) appears to act as an inflammatory mediator on monocytic cells. Exogenous NO augmented release of chemokines from human promonocytic U937 cells and peripheral blood mononuclear cells. Pharmacological strategies aiming at modulation of NO-induced release of interleukin-8 (IL-8) were investigated in U937 cells in detail. Release of IL-8 was down-regulated by transforming growth factor beta2 (TGF-beta2), by the protein tyrosine-kinase inhibitor genistein, and via rises in intracellular cyclic AMP, generated by prostaglandin E(2), rolipram, pentoxifylline, forskolin, or dibutyryl-cyclic AMP. In addition, incubation with the synthetic glucocorticoid dexamethasone or suppression of activity of p38 mitogen-activated protein (MAP) kinases by SB-203580 modulated release of IL-8. Activation of p38 MAP kinases was confirmed by the demonstration of an augmented appearance of phosphorylated p38 in the presence of NO. The present data suggest that exposure to exogenous NO resembles activation of U937 cells by proinflammatory stimuli. The anti-inflammatory cytokine TGF-beta2, as well as anti-inflammatory or immunosuppressive agents such as genistein, pentoxifylline, rolipram, dexamethasone, and SB-203580 modulate inflammatory, chemokine-inducing actions of NO.
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Affiliation(s)
- H Mühl
- Pharmazentrum Frankfurt, Klinikum der Johann Wolfgang Goethe-Universität Frankfurt am Main, Theodor-Stern-Kai 7, D-65090 am Main, Frankfurt, Germany.
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19
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Li W, Lin J, Adams GL, Juhn SK. Expression of inducible nitric oxide synthase (iNOS) in middle ear epithelial cells by IL-1beta and TNF-alpha. Int J Pediatr Otorhinolaryngol 2000; 55:91-8. [PMID: 11006448 DOI: 10.1016/s0165-5876(00)00372-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE The importance of nitric oxide (NO) in the development of mucoid middle ear effusion (MMEE) has been reported, but the mechanism regulating NO release is unclear. We hypothesized that middle ear epithelial cells (MEEC) are an important source of NO and that cytokines may be responsible for inducible nitric oxide synthase (iNOS) mRNA expression in middle ear epithelial cells. This study aims to identify and localize iNOS in middle ear epithelium, and to characterize the effects of cytokines IL-1beta and TNF-alpha on the expression and regulation of iNOS in rat middle ear epithelial cells. METHODS In vitro study: 40 Healthy adult Sprague-Dawley rats weighing 200-250 g were used as donors of MEEC. Cultured MEEC were exposed to IL-1beta (10 ng/ml), TNF-alpha (5 ng/ml) or PBS (negative control) stimulation for 16 h. In vivo study: A total of 45 healthy adult Sprague-Dawley rats weighing 200-250 grams were used for this study. The tympanic bullae were exposed bilaterally by a submandibular approach. Animals were equally divided into three groups and inoculated with either 250 ng of IL-1beta, 250 ng of TNF-alpha or PBS. A PBS group served as control. Expression of iNOS mRNA in MEEC from both in vivo and in vitro studies was determined by RT-PCR using specific primers. Expression of iNOS protein in MEEC was determined by immunocytochemistry and Western blot using specific anti-iNOS antibody. RESULTS Primary culture of rat MEEC was positively stained by cytokeratin antibody, but not by vimentin, indicating the epithelial origin of the cultured cells. RT-PCR revealed that cultured MEEC without treatment of IL-1 beta or TNF-alpha did not express iNOS mRNA whereas cultured MEEC treated with IL-1beta or TNF-alpha for 16 h expressed iNOS mRNA. Both immunocytochemistry and Western blot demonstrated the expression of iNOS protein in the majority of cultured MEEC treated with IL-1beta or TNF-alpha for 16 h, whereas the expression of iNOS protein was not detectable in MEEC without treatment. Expression of iNOS protein in vivo was observed in middle ear mucosa treated with IL-1beta and TNF-alpha by immunohistochemistry. CONCLUSION Expression of iNOS mRNA and iNOS protein is induced in MEEC following the treatment of cytokines IL-1beta or TNF-alpha both in vivo and in vitro. The results of the present study demonstrate that rat MEEC possess the capacity to express iNOS after IL-1beta and TNF-alpha stimulation.
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Affiliation(s)
- W Li
- Department of Otolaryngology, School of Medicine, University of Minnesota, Minneapolis, MN 55455, USA
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Lähde M, Korhonen R, Moilanen E. Regulation of nitric oxide production in cultured human T84 intestinal epithelial cells by nuclear factor-kappa B-dependent induction of inducible nitric oxide synthase after exposure to bacterial endotoxin. Aliment Pharmacol Ther 2000; 14:945-54. [PMID: 10886052 DOI: 10.1046/j.1365-2036.2000.00781.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Intestinal epithelium is consistently in contact with lipopolysaccharide (LPS) produced by intraluminal microbes. LPS induces nitric oxide production in many rodent cells, but in human cells it is very differently regulated. AIM To test the hypothesis that exposure to LPS up-regulates nitric oxide synthesis in human intestinal epithelium. METHODS AND RESULTS LPS induced nitric oxide synthesis in T84 cells in a time- and dose-dependent manner whereas detectable amounts of peroxynitrite were not produced. A novel selective inducible nitric oxide synthase (iNOS) inhibitor 1400 W potently inhibited LPS-induced nitric oxide synthesis in T84 cells while dexamethasone was relatively ineffective. Nitric oxide production was sensitive to cycloheximide, indicating that it was dependent on de novo protein synthesis. Nuclear factor-kappa B (NF-kappa B) inhibitor pyrrolidinedithiocarbamate abolished iNOS and nitric oxide production. Nitric oxide synthesis was also suppressed by genistein (tyrosine kinase inhibitor) and PD 98059 (p44/42 MAP kinase inhibitor) but enhanced by SB 203580 (p38 MAP kinase inhibitor). CONCLUSIONS Intestinal epithelial cells express iNOS and produce nitric oxide in a nuclear factor-kappa B-dependent manner when exposed to LPS. The process is regulated by tyrosine kinases, and p44/42 and p38 MAP kinases. Because nitric oxide acts as an antimicrobial agent and immune modulator, these findings are implicated in the regulation of gut mucosal immunity.
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Affiliation(s)
- M Lähde
- The Immunopharmacological Research Group, Medical School, University of Tampere, and the Department of Clinical Chemistry, Tampere University Hospital, Finland
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