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1.
Clin Immunol ; 242: 109083, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35908638

RESUMEN

(Leukaemia derived) dendritic cells (DC, DCleu) are potent stimulators of anti-leukaemic activity in acute myeloid leukaemia (AML) and can be generated with immunomodulatory kits containing granulocyte-macrophage-colony-stimulating-factor (GM-CSF), prostaglandin-E1 (PGE1), prostaglandin-E2 (PGE2) and/or picibanil (OK-321). Potential adverse effects initiated through kits, especially the proliferation of blasts, must be ruled out to ensure treatment safety. We quantified proliferating blasts with the proliferation markers CD71 and Ki-67 and the novel proliferation marker IPO-38 before and after kit treatment ex vivo. IPO-38 hereby appeared to be the most sensitive marker; a combination with CD71 may add value when assessing proliferation kinetics. Kit treatment did not or only slightly (<5%) induce blast proliferation in most cases. An induction of blast proliferation was only found in single cases and could be compensated by DCleu-induced anti-leukaemic activity in most times. Overall, we appraise kit treatment to be safe in vivo.


Asunto(s)
Leucemia Mieloide Aguda , Biomarcadores , Proliferación Celular , Células Dendríticas , Humanos , Prostaglandinas/farmacología , Prostaglandinas E/farmacología
2.
Cancer Immunol Immunother ; 71(12): 2901-2911, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35471603

RESUMEN

BACKGROUND: Dendritic cell (DC) therapy counts to the promising strategies how to weaken and eradicate cancer disease. We aimed to develop a good manufacturing practice (GMP) protocol for monocyte-derived DC (Mo-DC) maturation using circulating tumor cells lysates with subsequent experimental T-cell priming in vitro. METHODS: DC differentiation was induced from a population of immunomagnetically enriched CD14 + monocytes out of the leukapheresis samples (n = 6). The separation was provided automatically, in a closed bag system, using CliniMACS Prodigy® separation protocols (Miltenyi Biotec). For differentiation and maturation of CD14 + cells, DendriMACs® growing medium with supplements (GM-CSF, IL-4, IL-6, IL-1B, TNFa, PGE) was used. Immature Mo-DCs were loaded with autologous circulating tumor cell (CTCs) lysates. Autologous CTCs were sorted out by size-based filtration (MetaCell®) of the leukapheresis CD14-negative fraction. A mixture of mature Mo-DCs and autologous non-target blood cells (NTBCs) was co-cultured and the activation effect of mature Mo-DCs on T-cell activation was monitored by means of multimarker gene expression profiling. RESULTS: New protocols for mMo-DC production using automatization and CTC lysates were introduced including a feasible in vitro assay for mMo-DC efficacy evaluation. Gene expression analysis revealed elevation for following genes in NTBC (T cells) subset primed by mMo-DCs: CD8A, CD4, MKI67, MIF, TNFA, CD86, and CD80 (p ≤ 0.01). CONCLUSION: Summarizing the presented data, we might conclude mMo-DCs were generated using CliniMACS Prodigy® machine and CTC lysates in a homogenous manner showing a potential to generate NTBC activation in co-cultures. Identification of the activation signals in T-cell population by simple multimarker-qPCRs could fasten the process of effective mMo-DC production.


Asunto(s)
Células Dendríticas , Monocitos , Células Neoplásicas Circulantes , Humanos , Células Dendríticas/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Interleucina-4/farmacología , Interleucina-6/farmacología , Monocitos/metabolismo , Células Neoplásicas Circulantes/metabolismo , Prostaglandinas E/farmacología
3.
Toxicol Appl Pharmacol ; 441: 115970, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-35259347

RESUMEN

Exposure to compounds present in petroleum and wastewaters from oil and gas extraction sites in the Alberta Oil Sands Region can impair reproductive health. It has been established that acid extractable organics found in oil sands process-affected water (OSPW) such as naphthenic acids (NA-fraction components; NAFC) can adversely affect reproductive outcomes. We have shown that NAFC exposure results in a significant upregulation of GDF15 in placental trophoblasts, a cellular stress marker known to be involved in human embryonic development and necessary for the maintenance of pregnancy. However, little is known regarding the mechanism(s) underlying NAFC-induced increases in GDF15 production during early placentation. The goal of this study was to examine the effects of NAFC exposure on the regulation of critical transcription factors of GDF15 in extravillous trophoblast cells. Of these transcription factors, inflammatory mediators including prostaglandins have been reported to inhibit proliferation and migration of trophoblast cells in vitro. Hence, the secondary goal of this study was to determine whether inflammation mediated through prostaglandin production is critical to GDF15 secretion. HTR-8/SVneo cells were exposed to an NAFC for 6 and 24 h to assess the expression of key transcriptional regulators, GDF15 secretion, and prostaglandin (PGE2) output. Treatment with NAFC (125 mg/L only) significantly increased GDF15 expression and secretion in association with upregulation of the transcription factors KLF4, EGR1, ATF3 and TP53. Similarly, PTGS2 (i.e. COX2) expression and PGE2 output were significantly increased at the same concentration. However, co-treatment with a COX2 selective antagonist (SC236) only partially blocked the NAFC-induced increase in PGE2 output and did not block GDF15 expression or secretion. These findings suggest that while NAFC may affect GDF15 production, it is not exclusively a result of prostaglandin-mediated inflammation. This study provides new insights into the mechanisms by which NAFC may adversely affect placental trophoblast cell function in mammals.


Asunto(s)
Yacimiento de Petróleo y Gas , Contaminantes Químicos del Agua , Animales , Ácidos Carboxílicos , Ciclooxigenasa 2 , Femenino , Factor 15 de Diferenciación de Crecimiento/genética , Humanos , Inflamación , Mamíferos , Placenta , Embarazo , Prostaglandinas , Prostaglandinas E/farmacología , Factores de Transcripción , Trofoblastos , Agua
4.
Respir Res ; 23(1): 136, 2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35643499

RESUMEN

BACKGROUND: Pulmonary hypertension is a common and serious complication of chronic obstructive pulmonary disease (COPD). Studies suggest that cigarette smoke can initiate pulmonary vascular remodelling by stimulating cell proliferation; however, the underlying cause, particularly the role of vasoactive prostanoids, is unclear. We hypothesize that cigarette smoke extract (CSE) can induce imbalanced vasoactive prostanoid release by differentially modulating the expression of respective synthase genes in human pulmonary artery smooth muscle cells (PASMCs) and endothelial cells (PAECs), thereby contributing to cell proliferation. METHODS: Aqueous CSE was prepared from 3R4F research-grade cigarettes. Human PASMCs and PAECs were treated with or without CSE. Quantitative real-time RT-PCR and Western blotting were used to analyse the mRNA and protein expression of vasoactive prostanoid syhthases. Prostanoid concentration in the medium was measured using ELISA kits. Cell proliferation was assessed using the cell proliferation reagent WST-1. RESULTS: We demonstrated that CSE induced the expression of cyclooxygenase-2 (COX-2), the rate-limiting enzyme in prostanoid synthesis, in both cell types. In PASMCs, CSE reduced the downstream prostaglandin (PG) I synthase (PGIS) mRNA and protein expression and PGI2 production, whereas in PAECs, CSE downregulated PGIS mRNA expression, but PGIS protein was undetectable and CSE had no effect on PGI2 production. CSE increased thromboxane (TX) A synthase (TXAS) mRNA expression and TXA2 production, despite undetectable TXAS protein in both cell types. CSE also reduced microsomal PGE synthase-1 (mPGES-1) protein expression and PGE2 production in PASMCs, but increased PGE2 production despite unchanged mPGES-1 protein expression in PAECs. Furthermore, CSE stimulated proliferation of both cell types, which was significantly inhibited by the selective COX-2 inhibitor celecoxib, the PGI2 analogue beraprost and the TXA2 receptor antagonist daltroban. CONCLUSIONS: These findings provide the first evidence that cigarette smoke can induce imbalanced prostanoid mediator release characterized by the reduced PGI2/TXA2 ratio and contribute to pulmonary vascular remodelling and suggest that TXA2 may represent a novel therapeutic target for pulmonary hypertension in COPD.


Asunto(s)
Fumar Cigarrillos , Hipertensión Pulmonar , Enfermedad Pulmonar Obstructiva Crónica , Proliferación Celular , Células Endoteliales , Humanos , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/metabolismo , Prostaglandinas/metabolismo , Prostaglandinas E/metabolismo , Prostaglandinas E/farmacología , Arteria Pulmonar/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , ARN Mensajero/metabolismo , Nicotiana , Remodelación Vascular
5.
Bioorg Med Chem Lett ; 74: 128920, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35931244

RESUMEN

mPGES-1 is found to be up-regulated in the dopaminergic neurons of the substantia nigra pars compacta (SNpc) of postmortem brain tissue from Parkinson's disease (PD) patients and neurotoxin 6-hydroxydopamine (6-OHDA)-induced PD mice. Since the genetic deletion of mPGES-1 abolished 6-OHDA-induced PGE2 production and 6-OHDA-induced dopaminergic neurodegeneration in vitro and in vivo models, mPGES-1 enzyme has the potential to be an important target for PD therapy. In the present work, we investigated whether a small organic molecule as mPGES-1 inhibitor could exhibit the neuroprotective effects against 6-OHDA-induced neurotoxicity in in vitro and in vivo models. For this research goal, a new series of arylsulfonyl hydrazide derivatives was prepared and investigated whether these compounds may protect neurons against 6-OHDA-induced neurotoxicity in both in vitro and in vivo studies. Among them, compound 7s (MPO-0144) as a mPGES-1 inhibitor (PGE2 IC50 = 41.77 nM; mPGES-1 IC50 = 1.16 nM) exhibited a potent neuroprotection (ED50 = 3.0 nM) against 6-OHDA-induced in PC12 cells without its own neurotoxicity (IC50 = >10 µM). In a 6-OHDA-induced mouse model of PD, administration of compound 7s (1 mg/kg/day, for 7 days, i.p.) ameliorated motor impairments and dopaminergic neuronal damage. These significant biological effects of compound 7s provided the first pharmacological evidence that mPGES-1 inhibitor could be a promising therapeutic agent for PD patients.


Asunto(s)
Fármacos Neuroprotectores , Enfermedad de Parkinson , Animales , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas , Ratones , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Oxidopamina/farmacología , Enfermedad de Parkinson/tratamiento farmacológico , Prostaglandinas E/farmacología , Prostaglandinas E/uso terapéutico , Ratas
6.
Cell Mol Biol Lett ; 27(1): 82, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36180831

RESUMEN

Influenza-related acute lung injury (ALI) is a life-threatening condition that results mostly from uncontrolled replication of influenza virus (IV) and severe proinflammatory responses. The methoxy flavonoid compound 5-methoxyflavone (5-MF) is believed to have superior biological activity in the treatment of cancer. However, the effects and underlying mechanism of 5-MF on IV-mediated ALI are still unclear. Here, we showed that 5-MF significantly improved the survival of mice with lethal IV infection and ameliorated IV-mediated lung edema, lung histological changes, and inflammatory cell lung recruitment. We found that 5-MF has antiviral activity against influenza A virus (IAV), which was probably associated with increased expression of radical S-adenosyl methionine domain containing 2 (RSAD2) and suppression of endosomal acidification. Moreover, IV-infected A549 cells with 5-MF treatment markedly reduced proinflammatory mediator expression (IL-6, CXCL8, TNF-α, CXCL10, CCL2, CCL3, CCL4, GM-CSF, COX-2, and PGE2) and prevented P-IKBα, P-P65, and P-P38 activation. Interestingly, we demonstrated that 5-MF treatment could trigger activation of AMP-activated protein kinase (AMPK)α in IV-infected A549 cells, as evidenced by activation of the AMPKα downstream molecule P53. Importantly, the addition of AMPKα blocker compound C dramatically abolished 5-MF-mediated increased levels of RSAD2, the inhibitory effects on H1N1 virus-elicited endosomal acidification, and the suppression expression of proinflammatory mediators (IL-6, TNF-α, CXCL10, COX-2 and PGE2), as well as the inactivation of P-IKBα, P-P65, and P-P38 MAPK signaling pathways. Furthermore, inhibition of AMPKα abrogated the protective effects of 5-MF on H1N1 virus-mediated lung injury and excessive inflammation in vivo. Taken together, these results indicate that 5-MF alleviated IV-mediated ALI and suppressed excessive inflammatory responses through activation of AMPKα signaling.


Asunto(s)
Lesión Pulmonar Aguda , Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Proteínas Quinasas Activadas por AMP/metabolismo , Lesión Pulmonar Aguda/metabolismo , Animales , Antivirales/farmacología , Ciclooxigenasa 2 , Flavonas , Flavonoides/farmacología , Flavonoides/uso terapéutico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Inflamación/tratamiento farmacológico , Subtipo H1N1 del Virus de la Influenza A/metabolismo , Virus de la Influenza A/metabolismo , Interleucina-6/metabolismo , Metionina/farmacología , Metionina/uso terapéutico , Ratones , FN-kappa B/metabolismo , Prostaglandinas E/farmacología , Prostaglandinas E/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo , Proteína p53 Supresora de Tumor , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
7.
Endocr Regul ; 56(1): 22-30, 2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35180822

RESUMEN

Objective. Carbamazepine (CBZ), a widely used antiepileptic drug, is one major cause of the idiosyncratic liver injury along with immune reactions. Conversely, prostaglandin E2 (PGE2) demonstrates a hepatoprotective effect by regulating immune reactions and promoting liver repair in various types of liver injury. However, the amount of hepatic PGE2 during CBZ-induced liver injury remains elusive. In this study, we aimed to evaluate the hepatic PGE2 levels during CBZ-induced liver injury using a mouse model. Methods. Mice were orally administered with CBZ at a dose of 400 mg/kg for 4 days, and 800 mg/kg on the 5th day. Results. Plasma alanine transaminase (ALT) level increased in some of mice 24 h after the last CBZ administration. Although median value of hepatic PGE2 amount in the CBZ-treated mice showed same extent as vehicle-treated control mice, it exhibited significant elevated level in mice with severe liver injury presented by a plasma ALT level >1000 IU/L. According to these results, mice had a plasma ALT level >1000 IU/L were defined as responders and the others as non-responders in this study. Even though, the hepatic PGE2 levels increased in responders, the hepatic expression and enzyme activity related to PGE2 production were not upregulated when compared with vehicle-treated control mice. However, the hepatic 15-hydroxyprostaglandin dehydrogenase (15-PGDH) expression and activity decreased significantly in responders when compared with control mice. Conclusions. These results indicate that elevated hepatic PGE2 levels can be attributed to the downregulation of 15-PGDH expression under CBZ-induced liver injury.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Enfermedad Hepática Inducida por Sustancias y Drogas , Carbamazepina/metabolismo , Carbamazepina/farmacología , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/metabolismo , Humanos , Hígado , Prostaglandinas E/metabolismo , Prostaglandinas E/farmacología
8.
Ren Fail ; 43(1): 168-179, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33459127

RESUMEN

The two primary mechanisms by which iodinated contrast media (CM) causes contrast-induced acute kidney injury (CIAKI) are the hemodynamic effect causing intrarenal vasoconstriction and the tubular toxic effect causing acute tubular necrosis. Inhibition of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), which degrades prostaglandin E2 (PGE2), promotes tissue repair and regeneration in many organs. PGE2 causes intrarenal arterial vasodilation. In this study, we investigated whether a 15-PGDH inhibitor can act as a candidate for blocking these two major mechanisms of CIAKI. We established a CIAKI mouse model by injecting a 10 gram of iodine per body weight (gI/kg) dose of iodixanol into each mouse tail vein. A 15-PGDH inhibitor (SW033291), PGE1, or PGE2 were administered to compare the renal functional parameters, histologic injury, vasoconstriction, and renal blood flow changes. In addition, human renal proximal tubular epithelial cells were cultured in a CM-treated medium. SW033291, PGE1, or PGE2 were added to compare any changes in cell viability and apoptosis rate. CIAKI mice that received SW033291 had lower serum levels of creatinine, neutrophil gelatinase-associated lipocalin, and kidney injury molecule 1 (p < 0.001); lower histologic injury score and TUNEL positive rates (p < 0.001); and higher medullary arteriolar area (p < 0.05) and renal blood flow (p < 0.001) than CM + vehicle group. In cell culture experiments, Adding SW033291 increased the viability rate (p < 0.05) and decreased the apoptosis rate of the tubular epithelial cells (p < 0.001). This 15-PGDH inhibitor blocks the two primary mechanisms of CIAKI, intrarenal vasoconstriction and tubular cell toxicity, and thus has the potential to be a novel prophylaxis for CIAKI. Abbreviations: 15-PGDH: 15-hydroxyprostaglandin dehydrogenase; AMP: adenosine monophosphate; CIAKI: contrast-induced acute kidney injury; CM: contrast media; EP: prostaglandin E2 receptor; hRPTECs: human-derived renal proximal tubule epithelial cells; KIM-1: kidney injury molecule-1; MTT: 3-(4,5-Dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide; NGAL: neutrophil gelatinase-associated lipocalin; PBS: phosphate-buffered saline; PGE1: prostaglandin E1; PGE2: prostaglandin E2; RBF: renal blood flow; TUNEL: terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling; α-SMA: α-Smooth muscle actin.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/prevención & control , Medios de Contraste/efectos adversos , Hidroxiprostaglandina Deshidrogenasas/antagonistas & inhibidores , Piridinas/farmacología , Tiofenos/farmacología , Animales , Creatinina/sangre , Femenino , Humanos , Riñón/fisiopatología , Lipocalina 2/sangre , Ratones , Ratones Endogámicos C57BL , Prostaglandinas E/farmacología , Ácidos Triyodobenzoicos/efectos adversos
9.
IUBMB Life ; 72(11): 2282-2289, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32893983

RESUMEN

While searching for a counterpart to cyclic AMP, a new compound was found to inhibit adenylate cyclase. It was identified as prostaglandyl-(15-4')-myo-inositol (1':2'-cyclic)-phosphate (cyclic PIP). The substrates for its biosynthesis are prostaglandin E (PGE) and the novel inositol phosphate, guanosine diphospho-4-myo-inositol 1:2-cyclic phosphate (n-IP). The basic regulatory properties of cyclic PIP are to inhibit dose-dependently protein kinase A (PKA) and to seven-fold activate protein ser/thr phosphatase holoenzyme. These regulations occur as rapidly as the activation of PKA by cyclic AMP. Such regulatory properties are essential for the meticulous regulation of the equilibrium between the phospho- and de-phospho-form of interconvertible enzymes. The synthesis of cyclic PIP is stimulated by insulin and noradrenaline (α-receptor action). The insulin-stimulated cyclic PIP synthase is active in a tyrosine-phosphorylated state. A comparable characterization of the adrenaline-stimulated cyclic PIP synthase is still incomplete. In streptozotocin-diabetic rats, the hormonal stimulation of cyclic PIP synthesis decreases with time. Cyclic PIP synthesis is activated by biguanides as metformin two to four-fold and by antihypertensive drugs two-fold. Inhibition of cyclic PIP synthesis leads to a metabolic state as observed in early-stage type-2 diabetes. In summary, all living cells synthesize cyclic PIP, which switches on anabolism, whereas cyclic AMP triggers catabolism.


Asunto(s)
AMP Cíclico/antagonistas & inhibidores , Diabetes Mellitus/patología , Fosfatos de Inositol/farmacología , Prostaglandinas E/farmacología , Animales , Diabetes Mellitus/metabolismo , Humanos
10.
Mol Hum Reprod ; 23(5): 271-281, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28333263

RESUMEN

STUDY QUESTION: Do intraluteal prostaglandins (PG) contribute to luteal regulation in women? SUMMARY ANSWER: Prostaglandin E (PGE), which is produced in human granulosa-lutein cells stimulated with luteotropic hCG, exerts similar luteotropic effects to hCG, and the expression of PG synthetic and metabolic enzymes in the human CL is driven toward less PGE but more prostaglandin F (PGF) during luteolysis. WHAT IS KNOWN ALREADY: Uterine PGF is a major luteolysin in many non-primate species but not in women. Increases in the PGF synthase, aldo-ketoreductase family one member C3 (AKR1C3), have been observed in the CL of marmoset monkeys during luteolysis. PGE prevents spontaneous or induced luteolysis in domestic animals. STUDY DESIGN, SIZE, DURATION: Human CL tissues staged as the early-luteal (n = 6), mid-luteal (n = 6), late-luteal (n = 5) and menstrual (n = 3) phases were obtained at the time of hysterectomy for benign gynecological conditions. Luteinized granulosa cells (LGCs) were purified from follicular fluids obtained from patients undergoing assisted conception. PARTICIPANTS/MATERIALS, SETTING, METHODS: Upon collection, one half of the CL was snap-frozen and the other was fixed with formalin and processed for immunohistochemical analysis of a PGE synthase (PTGES). Quantitative RT-PCR was employed to examine changes in the mRNA abundance of PG synthetic and metabolic enzymes, steroidogenic enzymes, and luteolytic molecules in the staged human CL and in human LGCs in vitro treated with hCG, PGE and PGF. A PGE withdrawal experiment was also conducted in order to reveal the effects of the loss of PGE in LGCs. Progesterone concentrations in the culture medium were measured. MAIN RESULTS AND THE ROLE OF CHANCE: The key enzyme for PGE synthesis, PTGES mRNA was abundant in the functional CL during the mid-luteal phase (P < 0.01), while mRNA abundance for genes involved in PGF synthesis (AKR1B1 and AKR1C1-3) increased in the CL during the late-luteal phase and menstruation (P < 0.05-0.001). PTGES mRNA expression positively correlated with that of 3ß-hydroxysteroid dehydrogenase (HSD3B1; r = 0.7836, P < 0.001), while AKR1C3 expression inversely correlated with that of HSD3B1 (r = -0.7514, P = 0.0012) and PTGES (r = -0.6923, P = 0.0042). PGE exerted similar effects to hCG-promoting genes, such as steroidogenic acute regulatory protein (STAR) and HSD3B1, to produce progesterone and luteotropic PGE, suppress PGF synthetic enzymes and down-regulate luteolytic molecules such as ßA- and ßB-inhibin subunits (INHBA and INHBB) and bone morphogenetic proteins (BMP2, BMP4 and BMP6). PGE withdrawal resulted in reductions in the enzymes that produce progesterone (STAR; P < 0.001) and PGE (PTGES; P < 0.001), and the capacity to produce PGE decreased, while the capacity to produce PGF increased during the culture. The addition of PGF did not recapitulate the luteolytic effects of PGE withdrawal. LARGE SCALE DATA: None. LIMITATIONS, REASONS FOR CAUTION: Changes in mRNA expression of PG synthetic and metabolic enzymes may not represent actual increases in PGF during luteolysis in the CL. The effects of PGF on luteal cells currently remain unclear and the mechanisms responsible for decreases in the synthesis of PGE in vitro and at luteolysis have not been elucidated in detail. WIDER IMPLICATIONS OF THE FINDINGS: The results obtained strongly support a luteotropic function of PGE in regulation of the human CL. They suggest that the main PG produced in human luteal tissue changes from PGE to PGF during the maturation and regression of the CL, and the loss of PGE is more important than the effects of PGF during luteolysis in women. This may be accompanied by reduced effects of LH/hCG in luteal cells, particularly decreased activation of cAMP/protein kinase A; however, the underlying mechanisms remain unknown. STUDY FUNDING AND COMPETING INTEREST(S): This study was supported by the Cunningham Trust to WCD, a Postdoctoral Fellowship for Research Abroad from the Japan Society for the Promotion of Science and the Suntory Foundation for Life Sciences to J.N.-K.; W.C.D. is supported by an MRC Centre Grant G1002033 and a Scottish Senior Clinical Fellowship. The authors have nothing to disclose.


Asunto(s)
Cuerpo Lúteo/metabolismo , Células de la Granulosa/metabolismo , Luteinización/fisiología , Luteólisis/genética , Prostaglandinas E/genética , 20-Hidroxiesteroide Deshidrogenasas/genética , 20-Hidroxiesteroide Deshidrogenasas/metabolismo , Aldehído Reductasa/genética , Aldehído Reductasa/metabolismo , Animales , Gonadotropina Coriónica/farmacología , Cuerpo Lúteo/citología , Cuerpo Lúteo/efectos de los fármacos , Femenino , Regulación de la Expresión Génica , Células de la Granulosa/citología , Células de la Granulosa/efectos de los fármacos , Humanos , Subunidades beta de Inhibinas/genética , Subunidades beta de Inhibinas/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Fase Luteínica/fisiología , Menstruación/fisiología , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Factor de Crecimiento Placentario/farmacología , Cultivo Primario de Células , Progesterona/biosíntesis , Progesterona/metabolismo , Progesterona Reductasa/genética , Progesterona Reductasa/metabolismo , Prostaglandina-E Sintasas/genética , Prostaglandina-E Sintasas/metabolismo , Prostaglandinas E/deficiencia , Prostaglandinas E/farmacología , Transducción de Señal , Esteroide Isomerasas/genética , Esteroide Isomerasas/metabolismo
11.
J Biol Chem ; 287(21): 17214-17223, 2012 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-22474323

RESUMEN

The enzyme cyclooxygenase-2 (COX-2) is rapidly and transiently up-regulated by a large variety of signals and implicated in pathologies such as inflammation and tumorigenesis. Although many signals cause COX-2 up-regulation, much less is known about mechanisms that actively down-regulate its expression. Here we show that the G protein-coupled receptor prostaglandin E(1) (EP(1)) reduces the expression of COX-2 in a concentration-dependent manner through a mechanism that does not require receptor activation. The reduction in COX-2 protein is not due to decreased protein synthesis and occurs because of enhancement of substrate-independent COX-2 proteolysis. Although EP(1) does not interfere with the entry of COX-2 into the endoplasmic reticulum-associated degradation cascade, it facilitates COX-2 ubiquitination through complex formation. Blockade of proteasomal activity results in degradation of the receptor and concomitant recovery in the expression of COX-2, suggesting that EP(1) may scaffold an unknown E3 ligase that ubiquitinates COX-2. These findings propose a new role for the EP(1) receptor in resolving inflammation through down-regulation of COX-2.


Asunto(s)
Ciclooxigenasa 2/biosíntesis , Regulación hacia Abajo , Regulación Enzimológica de la Expresión Génica , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Subtipo EP1 de Receptores de Prostaglandina E/metabolismo , Línea Celular Tumoral , Ciclooxigenasa 2/genética , Relación Dosis-Respuesta a Droga , Retículo Endoplásmico/genética , Retículo Endoplásmico/metabolismo , Células HEK293 , Humanos , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Prostaglandinas E/metabolismo , Prostaglandinas E/farmacología , Complejo de la Endopetidasa Proteasomal/genética , Subtipo EP1 de Receptores de Prostaglandina E/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación/genética
12.
Invest New Drugs ; 30(5): 1865-77, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21931968

RESUMEN

Chronic inflammation is associated with 25% of all cancers. In the inflammation-cancer axis, prostaglandin E(2) (PGE(2)) is one of the major players. PGE(2) synthases (PGES) are the enzymes downstream of the cyclooxygenases (COXs) in the PGE(2) biosynthesis pathway. Microsomal prostaglandin E(2) synthase 1 (mPGES-1) is inducible by pro-inflammatory stimuli and constitutively expressed in a variety of cancers. The potential role for this enzyme in tumorigenesis has been reported and mPGES-1 represents a novel therapeutic target for cancers. In order to identify novel small molecule inhibitors of mPGES-1, we screened the ChemBridge library and identified 13 compounds as potential hits. These compounds were tested for their ability to bind directly to the enzyme using surface plasmon resonance spectroscopy and to decrease cytokine-stimulated PGE(2) production in various cancer cell lines. We demonstrate that the compound PGE0001 (ChemBridge ID number 5654455) binds to human mPGES-1 recombinant protein with good affinity (K(D) = 21.3 ± 7.8 µM). PGE0001 reduces IL-1ß-induced PGE(2) release in human HCA-7 colon and A549 lung cancer cell lines with EC(50) in the sub-micromolar range. Although PGE0001 may have alternative targets based on the results from in vitro assays, it shows promising effects in vivo. PGE0001 exhibits significant anti-tumor activity in SW837 rectum and A549 lung cancer xenografts in SCID mice. Single injection i.p. of PGE0001 at 100 mg/kg decreases serum PGE(2) levels in mice within 5 h. In summary, our data suggest that the identified compound PGE0001 exerts anti-tumor activity via the inhibition of the PGE(2) synthesis pathway.


Asunto(s)
Antiinflamatorios/farmacología , Antineoplásicos/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/metabolismo , Dinoprostona/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Células HCT116 , Células HT29 , Humanos , Inflamación/metabolismo , Oxidorreductasas Intramoleculares/metabolismo , Neoplasias Pulmonares/metabolismo , Ratones , Ratones SCID , Microsomas/metabolismo , Prostaglandina-E Sintasas , Prostaglandina-Endoperóxido Sintasas/metabolismo , Prostaglandinas E/farmacología , Resonancia por Plasmón de Superficie
13.
J Refract Surg ; 38(9): 587-594, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36098390

RESUMEN

PURPOSE: To assess whether aqueous cytokine profiles and pupil size are altered when high capsulotomy energy is used in eyes undergoing femtosecond laser-assisted cataract surgery (FLACS), and if preoperative use of a topical non-steroidal anti-inflammatory drug (NSAID) has an effect on this. METHODS: This prospective study recruited 83 eyes (63 patients) that were allocated to four treatment groups: conventional phacoemulsification (n = 20 eyes); FLACS with 90% capsulotomy energy without NSAID pretreatment (n = 20 eyes); FLACS with 90% capsulotomy energy with NSAID pre-treatment (n = 21 eyes); and FLACS with 150% capsulotomy energy with NSAID pretreatment (n = 22 eyes). Aqueous humor was collected before and after phacoemulsification to assess cytokine profiles. Pupil size was measured before and after laser capsulotomy. RESULTS: FLACS increased aqueous concentrations of pros-taglandin E2 (PGE2), interferon γ (IFN-γ), and interleukin 6 (IL-6) compared to conventional phacoemulsification. However, when increasing capsulotomy energy from 90% to 150% (with topical NSAID pretreatment), there was no significant increase in aqueous concentrations of PGE2 (37.7 ± 21.7 vs 33.6 ± 27.6 pg/mL, P = .99), IFN-γ (3.6 ± 1.1 vs 3.6 ± 0.8 pg/mL, P = .99), or IL-6 (7.1 ± 2.9 vs 6.3 ± 2.4 pg/mL, P = .99). For 90% and 150% capsulotomy energy, there was significant miosis following laser capsulotomy. Increased PGE2 concentration was significantly correlated with a reduction in pupil area (r = -0.58, P < .001) and pupil diameter (r = -0.57, P < .001). However, when a topical NSAID was given preoperatively, there was no difference in the degree of miosis between the 90% and 150% capsulotomy energy groups. CONCLUSIONS: Pretreatment with a topical NSAID prevented a rise in PGE2, IFN-γ, and IL-6 levels and excessive miosis when a higher capsulotomy energy was used. When a topical NSAID is used preoperatively, it is safe to use higher capsulotomy energy settings (with a low pulse energy femtosecond laser system) to achieve a satisfactory capsulotomy. [J Refract Surg. 2022;38(9):587-594.].


Asunto(s)
Catarata , Terapia por Láser , Antiinflamatorios no Esteroideos/uso terapéutico , Catarata/etiología , Humanos , Interleucina-6/farmacología , Terapia por Láser/efectos adversos , Rayos Láser , Miosis , Estudios Prospectivos , Prostaglandinas E/farmacología , Pupila
14.
Arthritis Res Ther ; 24(1): 212, 2022 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-36064735

RESUMEN

BACKGROUND: Tophi are lesions commonly present at sites of bone erosion in gout-affected joints. The tophus comprises a core of monosodium urate (MSU) crystals surrounded by soft tissue that contains macrophages and other immune cells. Previous studies found that MSU crystals directly reduce osteoblast viability and function. The aim of the current study was to determine the indirect, macrophage-mediated effects of MSU crystals on osteoblasts. METHODS: Conditioned medium from the RAW264.7 mouse macrophage cell line cultured with MSU crystals was added to the MC3T3-E1 mouse osteoblastic cell line. Conditioned medium from the THP-1 human monocytic cell line cultured with MSU crystals was added to primary human osteoblasts (HOBs). Matrix mineralization was assessed by von Kossa staining. Gene expression was determined by real-time PCR, and concentrations of secreted factors were determined by enzyme-linked immunosorbent assay. RESULTS: In MC3T3-E1 cells cultured for 13 days in an osteogenic medium, the expression of the osteoblast marker genes Col1a1, Runx2, Sp7, Bglap, Ibsp, and Dmp1 was inhibited by a conditioned medium from MSU crystal-stimulated RAW264.7 macrophages. Mineral staining of MC3T3-E1 cultures on day 21 confirmed the inhibition of osteoblast differentiation. In HOB cultures, the effect of 20 h incubation with a conditioned medium from MSU crystal-stimulated THP-1 monocytes on osteoblast gene expression was less consistent. Expression of the genes encoding cyclooxygenase-2 and IL-6 and secretion of the proinflammatory mediators PGE2 and IL-6 were induced in MC3T3-E1 and HOBs incubated with conditioned medium from MSU crystal-stimulated macrophages/monocytes. However, inhibition of cyclooxygenase-2 activity and PGE2 secretion from HOBs indicated that this pathway does not play a major role in mediating the indirect effects of MSU crystals in HOBs. CONCLUSIONS: Factors secreted from macrophages stimulated by MSU crystals attenuate osteoblast differentiation and induce the expression and secretion of proinflammatory mediators from osteoblasts. We suggest that bone erosion in joints affected by gout results from a combination of direct and indirect effects of MSU crystals.


Asunto(s)
Artritis Gotosa , Gota , Animales , Artritis Gotosa/patología , Medios de Cultivo Condicionados/farmacología , Ciclooxigenasa 2 , Gota/genética , Humanos , Interleucina-6/metabolismo , Macrófagos , Ratones , Osteoblastos/metabolismo , Prostaglandinas E/farmacología , Ácido Úrico/farmacología
15.
Acta Biomater ; 148: 230-243, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35724919

RESUMEN

The delivery of salicylic acid or its derivatives to tumor tissue in the form of nanomedicine is critical for the studies on their potential synergistic mechanism in tumor therapy and chemoprevention considering the dangerous bleeding in the high-dose oral administration. To deepen the understanding of their role in adjusting immunosuppressive tumor microenvironment (ITM), herein, we firstly developed a hypoxia-sensitive Fe-5,5'-azosalicylic acid nanoscale coordination polymer nanomedicines (FeNCPs) via a "old drugs new tricks" strategy for synergistic chemodynamic therapy (CDT) and remodulation of ITM to elevate antitumor immunotherapy effect. PEGylated FeNCPs could be reductively cleaved to release 5-aminosalicylic acid (5-ASA) and ferric ions by azo-reductase under hypoxic conditions, which could induce tumor cell death by Fenton reaction-catalysis enhanced CDT and 5-ASA-converted carboxylquinone to promote the production of •OH. Meanwhile, cyclooxygenase-2 (COX-2) and its enzymatic product prostaglandin E2 (PGE2), as immune negative regulatory molecules, can promote tumor progression and immune tolerance. The released 5-ASA as a COX inhibitor could suppress the expression of PGE2, and Fe3+ was employed to reeducate M2-like tumor-associated macrophages (TAMs) to M1-like phenotype, which could initiate antitumor immune response to reach better antitumor immunotherapy. This work broadens the application of salicylic acid derivatives in antitumor immunotherapy, and provides a new strategy for their "old drugs new tricks". STATEMENT OF SIGNIFICANCE: Cyclooxygenase-2 (COX-2) and its enzymatic product prostaglandin E2 (PGE2), as immune negative regulatory molecules, facilitate the differentiation of immune cells into immunosuppressive cells to build the immunosuppressive tumor microenvironment, which can promote tumor progression and immune tolerance. Thus, down-regulation of COX-2/PGE2 expression may be a key approach to tumor treatments. Meanwhile, as a class of inhibitors of COX-2/PGE2, the potential mechanism of aspirin or 5-aminosalicylic acid has been a mystery in tumor therapy and chemoprevention. To expand the application of aspirin family nanomedicine in biomedicine, herein, we firstly developed a hypoxia-sensitive Fe-5,5'-azosalicylic acid nanoscale coordination polymer nanomedicines via a "old drugs new tricks" strategy for synergistic chemodynamic therapy and remodulation of immunosuppressive tumor microenvironment to elevate antitumor immunotherapy effect.


Asunto(s)
Neoplasias , Microambiente Tumoral , Aspirina/farmacología , Línea Celular Tumoral , Ciclooxigenasa 2 , Humanos , Hipoxia , Factores Inmunológicos/farmacología , Inmunoterapia , Mesalamina/farmacología , Mesalamina/uso terapéutico , Nanomedicina , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Polímeros/farmacología , Prostaglandinas E/farmacología , Prostaglandinas E/uso terapéutico , Ácido Salicílico/farmacología , Ácido Salicílico/uso terapéutico
16.
J Oleo Sci ; 71(10): 1481-1492, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36089399

RESUMEN

Renal tissue plays a crucial function in maintaining homeostasis, making it vulnerable to xenobiotic toxicity. Pueraria montana has more beneficial potential against the various diseases and has long history used as a traditional Chinese medicine. But its effect against the renal cancer not scrutinize. The goal of this study is to see if Pueraria montana can protect rats from developing kidney tumors caused by diethylnitrosamine (DEN) and ferric nitrite (Fe-NTA). Wistar rats was selected for the current study and DEN (use as an inducer) and Fe-NTA (promoter) for induction the renal cancer. For 22 weeks, the rats were given orally Pueraria montana (12.5, 25, and 50 mg/kg) treatment. At regular intervals, the body weight and food intake were calculated. The rats were macroscopically evaluated for identification of cancer in the renal tissue. The renal tumor makers, renal parameters, antioxidant enzymes, phase I and II enzymes, inflammatory cytokines and mediators were estimated at end of the experimental study. Pueraria montana treated rats displayed the suppression of renal tumors, incidence of the tumors along with suppression of tumor percentage. Pueraria montana treated rats significantly (p < 0.001) increased body weight and suppressed the renal weight and food intake. It also reduced the level of renal tumor marker ornithine decarboxylase (ODC) and [3H] thymidine incorporation along with suppression of renal parameter such as uric acid, blood urea nitrogen (BUN), urea and creatinine. Pueraria montana treatment significantly (p < 0.001) altered the level of phase enzymes and antioxidant. Pueraria montana treatment significantly (p < 0.001) repressed the level of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and improved the level of interleukin-10 (IL-10). Pueraria montana treatment suppressed the level of prostaglandin (PGE2), cyclooxygenase-2 (COX-2), nuclear kappa B factor (NF-κB) and transforming growth factor beta 1 (TGF-ß1). Pueraria montana suppressed the inflammatory necrosis, size the bowman capsules in the renal histopathology. Pueraria montana exhibited the chemoprotective effect via dual mechanism such as suppression of inflammatory reaction and oxidative stress.


Asunto(s)
Neoplasias Renales , Pueraria , Animales , Antioxidantes/farmacología , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/farmacología , Peso Corporal , Creatinina/farmacología , Ciclooxigenasa 2/metabolismo , Dietilnitrosamina/farmacología , Compuestos Férricos , Inflamación/tratamiento farmacológico , Interleucina-10 , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Neoplasias Renales/inducido químicamente , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/metabolismo , FN-kappa B/metabolismo , Ácido Nitrilotriacético/análogos & derivados , Nitritos/farmacología , Ornitina Descarboxilasa/metabolismo , Ornitina Descarboxilasa/farmacología , Estrés Oxidativo , Prostaglandinas , Prostaglandinas E/metabolismo , Prostaglandinas E/farmacología , Pueraria/metabolismo , Ratas , Ratas Wistar , Timidina/metabolismo , Timidina/farmacología , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Urea , Ácido Úrico/farmacología , Xenobióticos/farmacología
17.
Platelets ; 22(7): 504-15, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21591981

RESUMEN

Several antiplatelet drugs that are used or in development as antithrombotic agents, such as antagonists of P2Y12 and EP3 receptors, act as antagonists at G(i)-coupled receptors, thus preventing a reduction in intracellular cyclic adenosine monophosphate (cAMP) in platelets. Other antiplatelet agents, including vascular prostaglandins, inhibit platelet function by raising intracellular cAMP. Agents that act as antagonists at G(i)-coupled receptors might be expected to promote the inhibitory effects of agents that raise cAMP. Here, we investigate the ability of the P2Y12 antagonists cangrelor, ticagrelor and prasugrel active metabolite (PAM), and the EP3 antagonist DG-041 to promote the inhibitory effects of modulators of platelet aggregation that act via cAMP. Platelet aggregation was measured by platelet counting in whole blood in response to the TXA2 mimetic U46619, thrombin receptor activating peptide and the combination of these. Vasodilator-stimulated phosphoprotein phosphorylation (VASP-P) was measured using a cytometric bead assay. Cangrelor always increased the potency of inhibitory agents that act by raising cAMP (PGI2, iloprost, PGD2, adenosine and forskolin). Ticagrelor and PAM acted similarly to cangrelor. DG-041 increased the potency of PGE1 and PGE2 as inhibitors of aggregation, and cangrelor and DG-041 together had more effect than either agent alone. Cangrelor and DG-041 were able to increase the ability of agents to raise cAMP in platelets as measured by increases in VASP-P. Thus, P2Y12 antagonists and the EP3 antagonist DG-041 are able to promote inhibition of platelet aggregation brought about by natural and other agents that raise intracellular cAMP. This action is likely to contribute to the overall clinical effects of such antagonists after administration to man.


Asunto(s)
Plaquetas/efectos de los fármacos , AMP Cíclico/metabolismo , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Antagonistas del Receptor Purinérgico P2Y/farmacología , Subtipo EP3 de Receptores de Prostaglandina E/antagonistas & inhibidores , Receptores Purinérgicos P2Y12/metabolismo , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/farmacología , Aspirina/farmacología , Plaquetas/metabolismo , Moléculas de Adhesión Celular/metabolismo , Humanos , Proteínas de Microfilamentos/metabolismo , Fosfoproteínas/metabolismo , Prostaglandinas E/farmacología
18.
Biochim Biophys Acta ; 1791(4): 307-13, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19233311

RESUMEN

Oxidative stress has been strongly implicated in pathological processes. Isoketals are highly reactive gamma-ketoaldehydes of the isoprostanes pathway of free radical-induced peroxidation of arachidonic acid that are analogous to cyclooxygenase-derived levuglandins. Because aldehydes, that are much less reactive than isoketals, have been shown to trigger platelet activation, we investigated the effect of one isoketal (E(2)-IsoK) on platelet aggregation. Isoketal potentiated aggregation and the formation of thromboxane B(2) in platelets challenged with collagen at a concentration as low as 1 nM. Moreover, the potentiating effect of 1 nM isoketal on collagen-induced platelet aggregation was prevented by pyridoxamine, an effective scavenger of gamma-ketoaldehydes. Furthermore, we provide evidence for the involvement of p38 mitogen-activated protein kinase in isoketal-mediated platelet priming, suggesting that isoketals may act upstream the activation of collagen-induced cytosolic phospholipase A(2). Additionally, the incubation of platelets with 1 nM isoketal led to the phosphorylation of cytosolic phospholipase A(2). The cytosolic phopholipase A(2) inhibitors AACOCF3 and MAFP both fully prevented the increase in isoketal-mediated platelet aggregation challenged with collagen. These results indicate that isoketals could play an important role in platelet hyperfunction observed in pathological states such as atherosclerosis and thrombosis through the activation of the endogenous arachidonic acid cascade.


Asunto(s)
Plaquetas/efectos de los fármacos , Isoprostanos/farmacología , Quinasas Quinasa Quinasa PAM/metabolismo , Activación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Proteínas Proto-Oncogénicas/metabolismo , Tromboxano B2/metabolismo , Plaquetas/metabolismo , Western Blotting , Colágeno/farmacología , Citosol/enzimología , Humanos , Fosfolipasas A2/metabolismo , Fosforilación , Prostaglandinas E/farmacología , Piridoxamina/farmacología , Complejo Vitamínico B/farmacología
19.
J Exp Med ; 164(4): 1259-73, 1986 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-3489807

RESUMEN

Immunization and intraperitoneal challenge of DBA/2 mice with L5178Y lymphoma cells results in the suppression and maintenance of the L5178Y cells in a tumor-dormant state in the peritoneal cavity for many months. Cell-mediated immune responses involving lymphocytes and macrophages are involved in maintenance of the tumor-dormant state. Macrophages that have increased immunosuppressive activity and that produce increased amounts of PGE2 appear in the peritoneal cavity of tumor-dormant mice before the breakdown of the tumor-dormant state and formation of ascitic tumors. We report here that the tumor-dormant state can be terminated with formation of ascitic tumors by treatment of tumor-dormant mice with PGE2. Treatment with indomethacin results in inhibition of tumor cell growth and elimination of all recoverable tumor cells. Cultures of peritoneal cells (PC) from mice harboring L5178Y cells in a tumor-dormant state were used to analyze the PGE2 and indomethacin effects. Tumor cells did not grow out in the high-cell density PC cultures prepared from many tumor-dormant mice, but addition of PGE2 to these cultures resulted in tumor cell growth. The tumor cell growth that did occur in the PC cultures from some tumor-dormant mice was associated with PGE2 production by the associated host cells, and the addition of indomethacin to these cultures inhibited both PGE2 synthesis and tumor cell growth. Removal of plastic-adherent cells from the PC cultures eliminated the restraint on tumor cell growth. These experiments suggest that L5178Y tumor cells are maintained in a tumor-dormant state by host peritoneal cells, which are under PGE2 regulation.


Asunto(s)
Indometacina/farmacología , Linfoma/inmunología , Prostaglandinas E/farmacología , Animales , Células Cultivadas , Dinoprostona , Femenino , Linfoma/patología , Macrófagos/inmunología , Ratones , Ratones Endogámicos DBA , Cavidad Peritoneal/citología , Prostaglandinas E/biosíntesis , Linfocitos T/inmunología
20.
J Exp Med ; 150(5): 1260-4, 1979 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-227981

RESUMEN

Receptors for prostaglandin E2 or histamine were measured on subpopulations of human lymphocytes, using the cyclic AMP increase after exposure to prostaglandin or histamine as an indicator for the presence of receptors. The cyclic AMP response to prostaglandin E2 was similar in unfractionated lymphocytes and the T-enriched and T-depleted fractions. Within the T-enriched population, T cells bearing a receptor for the Fc portion of IgG (T gamma-cells) had a 27.4-fold rise in cyclic AMP after exposure to prostaglandin E2, whereas the remaining T cells (non-T gamma cells) had a fourfold increase. It would appear that prostaglandin receptors are concentrated on a small subfraction of T gamma cells, comprising approximately 15% of the T-cell population. The cyclic AMP response to histamine was less than twofold in all lymphocyte fractions.


Asunto(s)
AMP Cíclico/metabolismo , Fragmentos Fc de Inmunoglobulinas , Inmunoglobulina G , Prostaglandinas E/farmacología , Linfocitos T/inmunología , Sitios de Unión , Células Cultivadas , AMP Cíclico/inmunología , Histamina/farmacología , Humanos , Activación de Linfocitos , Linfocitos T/clasificación , Linfocitos T/metabolismo
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