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1.
Immunity ; 51(2): 298-309.e6, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31399281

RESUMEN

T-helper (Th) cell differentiation drives specialized gene programs that dictate effector T cell function at sites of infection. Here, we have shown Th cell differentiation also imposes discrete motility gene programs that shape Th1 and Th2 cell navigation of the inflamed dermis. Th1 cells scanned a smaller tissue area in a G protein-coupled receptor (GPCR) and chemokine-dependent fashion, while Th2 cells scanned a larger tissue area independent of GPCR signals. Differential chemokine reliance for interstitial migration was linked to STAT6 transcription-factor-dependent programming of integrin αVß3 expression: Th2 cell differentiation led to high αVß3 expression relative to Th1 cells. Th1 and Th2 cell modes of motility could be switched simply by manipulating the amount of αVß3 on the cell surface. Deviating motility modes from those established during differentiation impaired effector function. Thus, programmed expression of αVß3 tunes effector T cell reliance on environmental cues for optimal exploration of inflamed tissues.


Asunto(s)
Inflamación/inmunología , Células TH1/inmunología , Células Th2/inmunología , Traslado Adoptivo , Animales , Diferenciación Celular , Movimiento Celular , Células Cultivadas , Técnicas de Reprogramación Celular , Quimiocinas/metabolismo , Humanos , Integrina alfaVbeta3/metabolismo , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Factor de Transcripción STAT6/metabolismo
2.
Acta Clin Croat ; 61(2): 354-358, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36818922

RESUMEN

Colorectal juvenile polyp as a pathologic entity was first described by Verse. These non-neoplastic lesions are most commonly found in children and infants, while in older children after the age of 14 and adults are a rare phenomenon. A 75-year-old female underwent colonoscopy. There was a pedunculated polyp in the transverse colon. Complete endoscopic electroresection of this polyp was performed and the polyp was sent for histopathologic analysis. Macroscopically, the polyp was described as a fragment of irregular round shape, size of about 2.5x2x1 cm, with fine-grained, reddish surface, showing dark red color on serial sections. Histologic examination of the polyp showed some irregularly distributed glands, some of which were cystically dilated. All glandular formations were coated with normal intestinal epithelium. The surface of the polyp was partially eroded and replaced by non-specific cellular granulation tissue. There were some signs of hemorrhagic infarction in the stroma of the polyp. Histopathologic examination indicated that histopathologic characteristics of this polyp corresponded to juvenile polyp. Juvenile polyps are very rarely found in adults. Therefore, we describe a case of this patient in her eighties with juvenile polyp localized in the transverse colon.


Asunto(s)
Pólipos del Colon , Hamartoma , Niño , Lactante , Femenino , Humanos , Adulto , Anciano , Pólipos del Colon/diagnóstico , Pólipos del Colon/patología , Pólipos del Colon/cirugía , Colonoscopía
3.
J Biol Chem ; 293(5): 1736-1744, 2018 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-29259133

RESUMEN

Infections by ranaviruses such as Frog virus 3 (Fv3), are significantly contributing to worldwide amphibian population declines. Notably, amphibian macrophages (Mφs) are important to both the Fv3 infection strategies and the immune defense against this pathogen. However, the mechanisms underlying amphibian Mφ Fv3 susceptibility and resistance remain unknown. Mφ differentiation is mediated by signaling through the colony-stimulating factor-1 receptor (CSF-1R) which is now known to be bound not only by CSF-1, but also by the unrelated interleukin-34 (IL-34) cytokine. Pertinently, amphibian (Xenopus laevis) Mφs differentiated by CSF-1 and IL-34 are highly susceptible and resistant to Fv3, respectively. Accordingly, in the present work, we elucidate the facets of this Mφ Fv3 susceptibility and resistance. Because cellular resistance to viral replication is marked by expression of antiviral restriction factors, it was intuitive to find that IL-34-Mφs possess significantly greater mRNA levels of select restriction factor genes than CSF-1-Mφs. Xenopodinae amphibians have highly expanded repertoires of antiviral interferon (IFN) cytokine gene families, and our results indicated that in comparison with the X. laevis CSF-1-Mφs, the IL-34-Mφs express substantially greater transcripts of representative IFN genes, belonging to distinct gene family clades, as well as their cognate receptor genes. Finally, we demonstrate that IL-34-Mφ-conditioned supernatants confer IFN-mediated anti-Fv3 protection to the virally susceptible X. laevis kidney (A6) cell line. Together, this work underlines the differentiation pathways leading to Fv3-susceptible and -resistant amphibian Mφ populations and defines the molecular mechanisms responsible for these differences.


Asunto(s)
Diferenciación Celular/inmunología , Infecciones por Virus ADN/inmunología , Inmunidad Innata , Macrófagos/inmunología , Ranavirus/inmunología , Animales , Interferones/inmunología , Interleucinas/inmunología , Macrófagos/virología , Receptor de Factor Estimulante de Colonias de Macrófagos/inmunología , Proteínas de Xenopus/inmunología , Xenopus laevis
4.
Plant Cell Physiol ; 60(12): 2692-2706, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31397873

RESUMEN

Abiotic environmental stresses have a negative impact on the yield and quality of crops. Understanding these stresses is an essential enabler for mitigating breeding strategies and it becomes more important as the frequency of extreme weather conditions increases due to climate change. This study analyses the response of barley (Hordeum vulgare L.) to a heat wave during grain filling in three distinct stages: the heat wave itself, the return to a normal temperature regime, and the process of maturation and desiccation. The properties and structure of the starch produced were followed throughout the maturational stages. Furthermore, the key enzymes involved in the carbohydrate supply to the grain were monitored. We observed differences in starch structure with well-separated effects because of heat stress and during senescence. Heat stress produced marked effects on sucrolytic enzymes in source and sink tissues. Early cessation of plant development as an indirect consequence of the heat wave was identified as the major contributor to final yield loss from the stress, highlighting the importance for functional stay-green traits for the development of heat-resistant cereals.


Asunto(s)
Amilopectina/metabolismo , Pared Celular/enzimología , Pared Celular/metabolismo , Hordeum/enzimología , Hordeum/metabolismo , beta-Fructofuranosidasa/metabolismo , Amilopectina/genética , Pared Celular/fisiología , Respuesta al Choque Térmico/fisiología , Hordeum/fisiología , beta-Fructofuranosidasa/genética
5.
Biol Chem ; 399(5): 447-452, 2018 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-29272250

RESUMEN

Gaucher disease (GD) is a lysosomal storage disorder, caused by an impaired function of ß-glucocerebrosidase, which results in accumulation of glucocerebroside in cells, and altered membrane ordering. Using electron paramagnetic resonance spin labeling, a statistically significant difference in the order parameter between the peripheral blood mononuclear cell membranes of GD patients and healthy controls was observed. Moreover, the results show that the introduction of the enzyme replacement therapy leads to the restoration of the physiological membrane fluidity. Accordingly, this simple method could serve as a preliminary test for GD diagnosis and therapy efficiency.


Asunto(s)
Membrana Celular/patología , Enfermedad de Gaucher/diagnóstico , Leucocitos Mononucleares/patología , Fluidez de la Membrana , Adulto , Espectroscopía de Resonancia por Spin del Electrón , Enfermedad de Gaucher/sangre , Enfermedad de Gaucher/terapia , Glucosilceramidasa/administración & dosificación , Humanos , Infusiones Intravenosas
6.
Artículo en Inglés | MEDLINE | ID: mdl-38924358

RESUMEN

Honey bees play a pivotal role in shaping ecosystems and sustaining human health as both pollinators and producers of health-promoting products. However, honey bee colony mortality is on the rise globally, driven by various factors, including parasites, pesticides, habitat loss, poor nutrition, and climate change. This has far-reaching consequences for the environment, economy, and human welfare. While efforts to address these issues are underway, the current progress in electron paramagnetic resonance (EPR) instrumentation affords using the immense potential of this magnetic resonance technique to study small samples such as honey bees. This paper presents the pioneering 2D in vivo EPR imaging experiment on a honey bee, revealing the ongoing redox-status of bees' intestines. This way, by monitoring the spatio-temporal changes of the redox-active spin-probes' EPR signal, it is possible to gain access to valuable information on the course of ongoing bees' pathologies and the prospect of following-up on the efficiency of applied therapies. Employing a selection of diverse spin-probes could further reveal pH levels and oxygen concentrations in bee tissues, allowing a noninvasive assessment of bee physiology. This approach offers promising strategies for safeguarding pollinators and understanding their biology, fostering their well-being and ecological harmony.

7.
Br J Nutr ; 109(11): 1940-8, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23069112

RESUMEN

Fructose-rich diets (FRD) cause cardiac insulin resistance manifested by impairment of Akt/endothelial NO synthase (eNOS) signalling. In contrast, oestradiol (E2) activates this signalling pathway in the heart. To study the ability of E2 to revert the detrimental effect of fructose on cardiac Akt/eNOS, female rats were subjected to a FRD and ovariectomy followed with or without E2 replacement. We also analysed the effects of the FRD and E2 on cardiac extracellular signal-regulated kinase (Erk 1/2) signalling related to their role in cardiac hypertrophy development. Expression of Akt, eNOS and Erk 1/2, as well as regulatory phosphorylations of these molecules were determined. The protein expression of cardiac Akt and eNOS was not affected by the diet or E2 treatment. However, the FRD was accompanied by a decrease in Akt phosphorylation at Ser(473) and Thr(308), and eNOS at Ser(1177), while the phosphorylation of eNOS at Thr(495) was increased. E2 replacement in ovariectomised fructose-fed rats caused a reversion of the diet effect on Akt and eNOS serine phosphorylation, but mostly had no effect on threonine phosphorylation of the molecules. The FRD and E2 treatment did not influence Erk 1/2 expression and phosphorylation and heart mass as well. The data show that E2 selectively suppress the negative effects of a FRD on Akt/eNOS signalling and probably point to the different effects of E2 on kinase/phosphatase pathways responsible for phosphorylation/dephosphorylation of Akt and eNOS. Furthermore, the results suggest that the heart of females in the reproductive period is partially protected against the damaging effects of increasedfructose intake.


Asunto(s)
Carbohidratos de la Dieta/efectos adversos , Estradiol/farmacología , Fructosa/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Carbohidratos de la Dieta/administración & dosificación , Estradiol/administración & dosificación , Estradiol/metabolismo , Femenino , Fructosa/administración & dosificación , Fructosa/efectos adversos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Corazón/fisiología , Resistencia a la Insulina , Óxido Nítrico Sintasa de Tipo III/genética , Ovariectomía , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos
8.
Dev Comp Immunol ; 140: 104623, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36563918

RESUMEN

Granulocyte-lineage cells are important innate immune effectors across all vertebrates. Named for conspicuous secretory granules, granulocytes have historically been studied for their antimicrobial roles. Although versions of these cells are found in all vertebrate species examined to date, disparate environmental and physiological pressures acting on distinct vertebrate classes have shaped many of the facets dictating granulocyte biology. Immune pressures further determine granulopoietic constraints, ultimately governing granulocyte functions. For amphibians that inhabit pathogen-rich aquatic environments for some or all their lives, their unique granulocyte biologies satisfy many of their antimicrobial needs. Amphibians also occupy an intermediate position in the evolution of vertebrate immune systems, using combinations of primitive (e.g., subcapsular liver) and more recently evolved (e.g., bone marrow) tissue sites for hematopoiesis and specifically, granulopoiesis. The last decade of research has revealed vertebrate granulocytes in general, and amphibian granulocytes in particular, are more complex than originally assumed. With dynamic leukocyte phenotypes, granulocyte-lineage cells are being acknowledged for their multifaceted roles beyond immunity in other physiological processes. Here we provide an overview of granulopoiesis in amphibians, highlight key differences in these processes compared to higher vertebrates, and identify open questions.


Asunto(s)
Granulocitos , Hematopoyesis , Animales , Granulocitos/fisiología , Hematopoyesis/fisiología , Anfibios , Biología
9.
Mol Cell Biochem ; 359(1-2): 301-13, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21858738

RESUMEN

Vascular endothelium is a key regulator of homeostasis. In physiological conditions it mediates vascular dilatation, prevents platelet adhesion, and inhibits thrombin generation. However, endothelial dysfunction caused by physical injury of the vascular wall, for example during balloon angioplasty, acute or chronic inflammation, such as in atherothrombosis, creates a proinflammatory environment which supports leukocyte transmigration toward inflammatory sites. At the same time, the dysfunction promotes thrombin generation, fibrin deposition, and coagulation. The serine protease thrombin plays a pivotal role in the coagulation cascade. However, thrombin is not only the key effector of coagulation cascade; it also plays a significant role in inflammatory diseases. It shows an array of effects on endothelial cells, vascular smooth muscle cells, monocytes, and platelets, all of which participate in the vascular pathophysiology such as atherothrombosis. Therefore, thrombin can be considered as an important modulatory molecule of vascular homeostasis. This review summarizes the existing evidence on the role of thrombin in vascular inflammation.


Asunto(s)
Endotelio Vascular/patología , Inflamación/etiología , Trombina/fisiología , Humanos , Enfermedades Vasculares/patología
10.
J Thromb Thrombolysis ; 33(2): 160-72, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22161772

RESUMEN

Vascular endothelium, as a key regulator of hemostasis, mediates vascular dilatation, prevents platelet adhesion, and inhibits thrombin generation. Endothelial dysfunction caused by acute or chronic inflammation, such as in atherosclerosis, creates a proinflammatory environment which supports leukocyte transmigration toward inflammatory sites, and at the same time promotes coagulation, thrombin generation, and fibrin deposition in an attempt to close the wound. Life-long persistent infection with human cytomegalovirus (HCMV) has been associated with atherosclerosis. In vivo studies have revealed that HCMV infection of the vessel wall affects various cells including monocytes/macrophages, smooth muscle cells (SMCs) and endothelial cells (ECs). HCMV-infected SMCs within vascular lesions display enhanced proliferation and impaired apoptosis, which contribute to intima-media thickening, plaque formation and restenosis. Monocytes play a central role in the process of viral dissemination, whereas ECs may represent a viral reservoir, maintaining persistent infection in HCMV-infected atherosclerotic patients following the primary infection. Persistent infection leads to dysfunction of ECs and activates proinflammatory signaling involving nuclear factor κB, specificity protein 1, and phosphatidylinositol 3-kinase, as well as expression of platelet-derived growth factor receptor. Activation of these pathways promotes enhanced proliferation and migration of monocytes and SMCs into the intima of the vascular wall as well as lipid accumulation and expansion of the atherosclerotic lesion. Moreover, HCMV infection induces enhanced expression of endothelial adhesion molecules and modifies the proteolytic balance in monocytes and macrophages. As a consequence, infected endothelium recruits naive monocytes from the blood stream, and the concomitant interaction between infected ECs and monocytes enables virus transfer to migrating monocytes. Endothelial damage promotes thrombin generation linking inflammation and coagulation. HCMV, in turn, enhances the thrombin generation. The virus carries on its surface the molecular machinery necessary to initiate thrombin generation, and in addition, may interact with the prothrombinase protein complex thereby facilitating thrombin generation. Thus, infection of endothelium may significantly increase the production of thrombin. This might not only contribute to thrombosis in patients with atherosclerosis, but might also induce thrombin-dependent proinflammatory cell activation. This review summarizes the existing evidence on the role of HCMV in vascular inflammation.


Asunto(s)
Aterosclerosis/inmunología , Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Trombosis/inmunología , Aterosclerosis/patología , Infecciones por Citomegalovirus/patología , Endotelio Vascular/inmunología , Endotelio Vascular/patología , Humanos , Trombosis/patología
11.
Appl Microbiol Biotechnol ; 89(5): 1611-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21279345

RESUMEN

Polyhydroxyalkanoates (PHAs) are natural polyesters synthesized by bacteria for carbon and energy storage that also have commercial potential as bioplastics. One promising class of carbon feedstocks for industrial PHA production is plant oils, due to the high carbon content of these compounds. The bacterium Ralstonia eutropha accumulates high levels of PHA and can effectively utilize plant oil. Growth experiments that include plant oil, however, are difficult to conduct in a quantitative and reproducible manner due to the heterogeneity of the two-phase medium. In order to overcome this obstacle, a new culture method was developed in which palm oil was emulsified in growth medium using the glycoprotein gum arabic as the emulsifying agent. Gum arabic did not influence R. eutropha growth and could not be used as a nutrient source by the bacteria. R. eutropha was grown in the emulsified oil medium and PHA production was measured over time. Additionally, an extraction method was developed to monitor oil consumption. The new method described in this study allows quantitative, reproducible R. eutropha experiments to be performed with plant oils. The method may also prove useful for studying growth of different bacteria on plant oils and other hydrophobic carbon sources.


Asunto(s)
Cupriavidus necator/crecimiento & desarrollo , Cupriavidus necator/metabolismo , Hidroxibutiratos/metabolismo , Aceites de Plantas/metabolismo , Poliésteres/metabolismo , Medios de Cultivo/química , Emulsiones/metabolismo , Goma Arábiga/química
12.
J Clin Med ; 10(3)2021 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-33540508

RESUMEN

Glucocorticoid (GC) resistance complicates the treatment of ~10-20% of children with nephrotic syndrome (NS), yet the molecular basis for resistance remains unclear. We used RNAseq analysis and in silico algorithm-based approaches on peripheral blood leukocytes from 12 children both at initial NS presentation and after ~7 weeks of GC therapy to identify a 12-gene panel able to differentiate steroid resistant NS (SRNS) from steroid-sensitive NS (SSNS). Among this panel, subsequent validation and analyses of one biologically relevant candidate, sulfatase 2 (SULF2), in up to a total of 66 children, revealed that both SULF2 leukocyte expression and plasma arylsulfatase activity Post/Pre therapy ratios were greater in SSNS vs. SRNS. However, neither plasma SULF2 endosulfatase activity (measured by VEGF binding activity) nor plasma VEGF levels, distinguished SSNS from SRNS, despite VEGF's reported role as a downstream mediator of SULF2's effects in glomeruli. Experimental studies of NS-related injury in both rat glomeruli and cultured podocytes also revealed decreased SULF2 expression, which were partially reversible by GC treatment of podocytes. These findings together suggest that SULF2 levels and activity are associated with GC resistance in NS, and that SULF2 may play a protective role in NS via the modulation of downstream mediators distinct from VEGF.

13.
J Thromb Thrombolysis ; 30(2): 164-71, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20155436

RESUMEN

Human cytomegalovirus (HCMV) establishes a life-long persistent infection. HCMV infection could be associated with chronic inflammatory diseases, such as cardiovascular disease and atherosclerosis. Here we observed that in HCMV (AD-169) pre-exposed human umbilical vein endothelial cells (HUVEC), thrombin-induced expression of IL-1alpha and M-CSF is markedly enhanced compared to the un-exposed cells. Study of the expression of thrombin receptor genes in HUVEC showed that HCMV triggered a time- and concentration-dependent expression of the thrombin receptors PAR1, PAR3 and PAR4 at the mRNA level. Induction of PAR1 and PAR3 mRNA expression is due to transcriptional activation of their promoters as shown by gene reporter assay. Furthermore, the virus induced expression of PAR1 and PAR3 but not PAR4 proteins, as analyzed by Western immunoblotting. However, flow cytometric analysis revealed that only PAR3, expressed at very low level in control HUVEC, is induced at the surface during the exposure to the virus. Our data suggest that although exposure to HCMV induces a minor increase of cell-surface receptors expression, it does make endothelial cells more responsive to additional thrombin stimulation.


Asunto(s)
Citomegalovirus/patogenicidad , Células Endoteliales/virología , Receptores de Trombina/metabolismo , Trombina/metabolismo , Venas Umbilicales/virología , Western Blotting , Células Cultivadas , Células Endoteliales/inmunología , Células Endoteliales/metabolismo , Citometría de Flujo , Humanos , Mediadores de Inflamación/metabolismo , Interleucina-1beta/metabolismo , Factor Estimulante de Colonias de Macrófagos/metabolismo , Regiones Promotoras Genéticas , ARN Mensajero/metabolismo , Receptor PAR-1/metabolismo , Receptores de Trombina/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo , Activación Transcripcional , Venas Umbilicales/citología , Venas Umbilicales/inmunología , Venas Umbilicales/metabolismo , Regulación hacia Arriba
14.
Dev Comp Immunol ; 113: 103798, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32745480

RESUMEN

The differentiation of distinct leukocyte subsets is governed by lineage-specific growth factors that elicit disparate expression of transcription factors and markers by the developing cell populations. For example, macrophages (Mφs) and granulocytes (Grns) arise from common granulocyte-macrophage progenitors in response to distinct myeloid growth factors. In turn, myelopoiesis of the Xenopus laevis anuran amphibian appears to be unique to other studied vertebrates in several respects while the functional differentiation of amphibian Mφs and Grns from their progenitor cells remains poorly understood. Notably, the expression of colony stimulating factor-1 receptor (CSF-1R) or CSF-3R on granulocyte-macrophage progenitors marks their commitment to Mφ- or Grn-lineages, respectively. CSF-1R is activated by the colony stimulating factor-1 (CSF-1) and interleukin (IL-34) cytokines, resulting in morphologically and functionally distinct Mφ cell types. Conversely, CSF-3R is ligated by CSF-3 in a process indispensable for granulopoiesis. Presently, we explore the relationships between X. laevis CSF-1-Mφs, IL-34-Mφs and CSF-3-Grns by examining their expression of key lineage-specific transcription factor and myeloid marker genes as well as their enzymology. Our findings suggest that while the CSF-1- and IL-34-Mφs share some commonalities, the IL-34-Mφs possess transcriptional patterns more akin to the CSF-3-Grns. IL-34-Mφs also possess robust expression of dendritic cell-associated transcription factors and surface marker genes, further underlining the difference between this cell type and the CSF-1-derived frog Mφ subset. Moreover, the three myeloid populations differ in their respective tartrate-resistant acid phosphatase, specific- and non-specific esterase activity. Together, this work grants new insights into the developmental relatedness of these three frog myeloid subsets.


Asunto(s)
Granulocitos/fisiología , Macrófagos/fisiología , Xenopus laevis/inmunología , Proteínas Anfibias/genética , Proteínas Anfibias/metabolismo , Animales , Biomarcadores/metabolismo , Diferenciación Celular , Linaje de la Célula , Factores Estimulantes de Colonias/metabolismo , Esterasas/metabolismo , Regulación del Desarrollo de la Expresión Génica , Interleucinas/genética , Interleucinas/metabolismo , Mielopoyesis , Receptor de Factor Estimulante de Colonias de Macrófagos/genética , Receptor de Factor Estimulante de Colonias de Macrófagos/metabolismo , Transcriptoma
15.
J Leukoc Biol ; 84(1): 215-23, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18436581

RESUMEN

CX3CL1 (fractalkine, neurotactin) is the sole CX3C chemokine. It induces monocyte locomotion in its cleaved form, but in its membrane-anchored form, it also acts as an adhesion molecule. The expression of CX3CL1 is up-regulated in endothelial cells by proinflammatory cytokines such as IL-1 or TNF-alpha. Here, we studied the effect of the serine protease thrombin on endothelial CX3CL1 induction and its putative relevance for monocyte function. In HUVEC, thrombin triggered a time- and concentration-dependent expression of CX3CL1 at the mRNA and the protein level as shown by RT-PCR, Western immunoblotting, and flow cytometric analysis. Thrombin induced CX3CL1 by activating protease-activated receptor 1 (PAR1) as demonstrated by the use of PAR1-activating peptide and the PAR1-specific antagonist SCH 79797. The thrombin-induced CX3CL1 expression was NF-kappaB-dependent, as shown by EMSA, ELISA, and by inhibition of the NF-kappaB signaling pathway by the IkappaB kinase inhibitor acety-11-keto-beta-boswellic acid or by transient overexpression of a transdominant-negative form of IkappaBalpha. Upon cocultivation of human monocytes with HUVEC, the thrombin-dependent induction of membrane-anchored CX3CL1 in HUVEC triggered monocyte adhesion and an enhanced release of the MCP-1/CCL2 by monocytes and potentiated the monocyte transendothelial migration. Accordingly, the recombinant extracellular domain of CX3CL1 induced CCL2 release by monocytes. Thus, the thrombin-induced monocyte/endothelial cell cross-talk mediated by increased CX3CL1 expression potentiates the CCL2 chemokine generation that might contribute to the recruitment of monocytes into inflamed areas.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Quimiocina CCL2/metabolismo , Quimiocina CX3CL1/metabolismo , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Monocitos/metabolismo , Trombina/farmacología , Línea Celular , Quimiocina CX3CL1/genética , Quimiotaxis/efectos de los fármacos , Técnicas de Cocultivo , Células Endoteliales/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Monocitos/efectos de los fármacos , FN-kappa B/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptor PAR-1/metabolismo , Venas Umbilicales/citología
16.
J Leukoc Biol ; 106(6): 1257-1269, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31535730

RESUMEN

Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), remains the leading global cause of death from an infectious agent. Mycobacteria thrive within their host Mϕs and presently, there is no animal model that permits combined in vitro and in vivo study of mycobacteria-host Mϕ interactions. Mycobacterium marinum (Mm), which causes TB in aquatic vertebrates, has become a promising model for TB research, owing to its close genetic relatedness to Mtb and the availability of alternative, natural host aquatic animal models. Here, we adopted the Xenopus laevis frog-Mm surrogate infection model to study host Mϕ susceptibility and resistance to mycobacteria. Mϕ differentiation is regulated though the CSF-1 receptor (CSF-1R), which is activated by CSF-1 and the unrelated IL-34 cytokines. Using combined in vitro and in vivo approaches, we demonstrated that CSF-1-Mϕs exacerbate Mm infections, are more susceptible to mycobacterial entry and are less effective at killing this pathogen. By contrast, IL-34-Mϕs confer anti-Mm resistance in vivo, are less susceptible to Mm entry and more effectively eliminate internalized mycobacteria. Moreover, we showed that the human CSF-1- and IL-34-Mϕs are likewise, respectively, susceptible and resistant to mycobacteria, and that both frog and human CSF-1-Mϕs are more prone to the spread of mycobacteria and to being infected by Mm-laden Mϕs than the respective IL-34-Mϕ subsets. This work marks the first report describing the roles of these Mϕ subsets in mycobacterial disease and may well lead to the development of more targeted anti-Mtb approaches.


Asunto(s)
Interleucinas/metabolismo , Factor Estimulante de Colonias de Macrófagos/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Infecciones por Mycobacterium no Tuberculosas/inmunología , Infecciones por Mycobacterium no Tuberculosas/metabolismo , Mycobacterium marinum/inmunología , Animales , Carga Bacteriana , Resistencia a la Enfermedad , Susceptibilidad a Enfermedades/inmunología , Perfilación de la Expresión Génica , Humanos , Macrófagos/microbiología , Infecciones por Mycobacterium no Tuberculosas/microbiología , Mycobacterium marinum/genética , Fagocitosis/genética , Fagocitosis/inmunología , Fagosomas/inmunología , Fagosomas/metabolismo , Xenopus
17.
Bioresour Technol ; 99(14): 6688-91, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18155904

RESUMEN

The antioxidant activity and contents of various polyphenol classes in the seeds of 20 soybean hybrids were evaluated. Total polyphenols, tannins and proanthocyanidins were determined after extraction of plant material with 70% aqueous acetone. In addition, flavonoid content was determined. Antioxidant activity of seed extracts was evaluated by DPPH free radical scavenging activity assay. A positive linear correlation between antioxidant activity and contents of total phenols, tannins and proanthocyanidins was established. The highest antioxidant activity was observed in the extracts of hybrids which have higher levels of all polyphenol classes examined. The most of the single-cross hybrids were poor in tannins which recommend them as good source for ensiled livestock feed. Results suggested that polyphenol content should be considered as an important feature of the soybean seed.


Asunto(s)
Antioxidantes/farmacología , Flavonoides/análisis , Glycine max/embriología , Fenoles/análisis , Extractos Vegetales/química , Semillas/química , Cromatografía en Capa Delgada , Flavonoides/farmacología , Fenoles/farmacología , Extractos Vegetales/farmacología , Polifenoles
18.
Front Immunol ; 9: 2058, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30258441

RESUMEN

The glutamic acid-leucine-arginine (ELR) motif is a hallmark feature shared by mammalian inflammatory CXC chemokines such the granulocyte chemo-attractant CXCL8 (interleukin-8, IL-8). By contrast, most teleost fish inflammatory chemokines lack this motif. Interestingly, the amphibian Xenopus laevis encodes multiple isoforms of CXCL8, one of which (CXCL8a) possesses an ELR motif, while another (CXCL8b) does not. These CXCL8 isoforms exhibit distinct expression patterns during frog development and following immune challenge of animals and primary myeloid cultures. To define potential functional differences between these X. laevis CXCL8 chemokines, we produced them in recombinant form (rCXCL8a and rCXCL8b) and performed dose-response chemotaxis assays. Our results indicate that compared to rCXCL8b, rCXCL8a is a significantly more potent chemo-attractant of in vivo-derived tadpole granulocytes and of in vitro-differentiated frog bone marrow granulocytes. The mammalian CXCL8 mediates its effects through two distinct chemokine receptors, CXCR1 and CXCR2 and our pharmacological inhibition of these receptors in frog granulocytes indicates that the X. laevis CXCL8a and CXCL8b both chemoattract tadpole and adult frog granulocytes by engaging CXCR1 and CXCR2. To delineate which frog cells are recruited by CXCL8a and CXCL8b in vivo, we injected tadpoles and adult frogs intraperitoneally with rCXCL8a or rCXCL8b and recovered the accumulated cells by lavage. Our transcriptional and cytological analyses of these tadpole and adult frog peritoneal exudates indicate that they are comprised predominantly of granulocytes. Interestingly, the granulocytes recruited into the tadpole, but not adult frog peritonea by rCXCL8b, express significantly greater levels of several pan immunosuppressive genes.


Asunto(s)
Quimiotaxis/inmunología , Evolución Molecular , Granulocitos/inmunología , Interleucina-8/inmunología , Proteínas de Xenopus/inmunología , Animales , Granulocitos/citología , Interleucina-8/genética , Proteínas de Xenopus/genética , Xenopus laevis
20.
Molecules ; 12(3): 576-81, 2007 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-17851412

RESUMEN

The contents and antioxidant ability of various classes of phenolic compounds present in the seeds of twenty soybean hybrids were evaluated. Total phenolics, tannins and proanthocyanidins were determined spectrophotometrically, after extraction of seeds with 70% aqueous acetone. In addition, the flavonoid contents were determined. The antioxidant activity of aqueous acetone extracts was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity assay. The highest contents of total phenolics were found in Serbian cultivar 1511 and Chinese cultivar LN92-7369, which also displayed the highest total antioxidant activity. Conversely, genotypes poor in phenolics also showed low levels of DPPH-radical scavenging activity. The results suggested that besides protein and oil contents, the phenolic contents should be also considered as an important characteristic feature of soybean seeds, and as a potential selection criterion for antioxidant activity in soybean.


Asunto(s)
Antioxidantes/metabolismo , Glycine max/química , Glycine max/metabolismo , Fenoles/análisis , Semillas/química , Semillas/metabolismo , Genotipo , Extractos Vegetales/química
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