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1.
Medicina (Kaunas) ; 60(6)2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38929484

RESUMEN

Cafestol, a bioactive compound found in coffee, has attracted considerable attention due to its potential impact on cardiovascular health. This review aims to comprehensively explore the association between cafestol and cardiovascular diseases. We delve into the mechanisms through which cafestol influences lipid metabolism, inflammation, and endothelial function, all of which are pivotal in cardiovascular pathophysiology. Moreover, we meticulously analyze epidemiological studies and clinical trials to elucidate the relationship between cafestol and cardiovascular outcomes. Through a critical examination of existing literature, we aim to provide insights into the potential benefits and risks associated with cafestol concerning cardiovascular health.


Asunto(s)
Enfermedades Cardiovasculares , Humanos , Café , Metabolismo de los Lípidos/efectos de los fármacos
2.
Acta Derm Venereol ; 103: adv00875, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36852577

RESUMEN

Chronic pruritus is an unpleasant sensory perception that negatively affects quality of life and is common among patients with type 2 diabetes mellitus. Current antipruritic therapies are insufficiently effective. Thus, the mediation of diabetic pruritus by histamine-independent pathways is likely. The aim of this study was to identify possible mediators responsible for diabetic pruritus. A total of 87 patients with type 2 diabetes mellitus were analysed, of whom 59 had pruritus and 28 did not. The 2 groups were assessed for baseline demographics, serum biochemistry parameters, cytokines, and chemokines. This study also investigated the associations of these factors with the severity of itching. Neither haemoglobin A1c nor serum creatinine levels were correlated with severity of itching. Significantly higher levels of interleukin-4 (p = 0.004), interleukin-13 (p = 0.006), granulocyte-macrophage colony-stimulating factor (p < 0.001) and C-X-C motif chemokine ligand 10 (p = 0.028) were observed in the patients with pruritus than in those without pruritus. Moreover, the levels of these mediators were positively correlated with the severity of itching. Thus, novel antipruritic drugs can be developed to target these molecules. This is the first study to compare inflammatory mediators comprehensively in patients with diabetes mellitus with pruritus vs those without pruritus.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Calidad de Vida , Prurito/diagnóstico , Prurito/tratamiento farmacológico , Prurito/etiología , Antipruriginosos , Citocinas
3.
Glycobiology ; 32(9): 760-777, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35789267

RESUMEN

Galectin-3 (GAL3) is a ß-galactoside-binding lectin expressed in CD4 T cells infected with human immunodeficiency virus-1 (HIV-1). GAL3 promotes HIV-1 budding by associating with ALIX and Gag p6. GAL3 has been shown to localize in membrane lipid rafts in dendritic cells and positively regulate cell migration. HIV-1 spreads between T cells by forming supramolecular structures (virological synapses [VSs]), whose integrity depends on lipid rafts. Here, we addressed the potential role of GAL3 in cell-to-cell transmission of HIV-1 in CD4 T cells. GAL3 expressed in donor cells was more important for facilitating HIV-1 cell-to-cell transfer than GAL3 expressed in target cells. GAL3 was found to be co-transferred with Gag from HIV-1-positive donor to HIV-1-negative target T cells. HIV-1 infection induced translocation of GAL3 together with Gag to the cell-cell interfaces and colocalize with GM1, where GAL3 facilitated VS formation. GAL3 regulated the coordinated transfer of Gag and flotillin-1 into plasma membrane fractions. Finally, depletion of GAL3 reduced the cholesterol levels in membrane lipid rafts in CD4 T cells. These findings provide evidence that endogenous GAL3 stimulates lipid raft components and facilitates intercellular HIV-1 transfer among CD4 T cells, offering another pathway by which GAL3 regulates HIV-1 infection. These findings may inform the treatment of HIV-1 infection based on targeting GAL3 to modulate lipid rafts.


Asunto(s)
Infecciones por VIH , VIH-1 , Proteínas Sanguíneas , Linfocitos T CD4-Positivos/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Galectinas , Humanos , Lípidos de la Membrana/análisis , Lípidos de la Membrana/metabolismo , Microdominios de Membrana/química
4.
Glycobiology ; 31(9): 1230-1238, 2021 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-34132764

RESUMEN

Glycosylation is important for biological functions of proteins and greatly affected by diseases. Exploring the glycosylation profile of the protein-specific glycosylation and/or the site-specific glycosylation may help understand disease etiology, differentiate diseases and ultimately develop therapeutics. Patients with multiple sclerosis (MS) and patients with neuromyelitis optica spectrum disorder (NMOSD) are sometimes difficult to differentiate due to the similarity in their clinical symptoms. The disease-related glycosylation profiles of MS and NMOSD have not yet been well studied. Here, we analyzed site-specific glycan profiles of serum proteins of these patients by using a recently developed mass spectrometry technique. A total of 286 glycopeptides from 49 serum glycoproteins were quantified and compared between healthy controls (n = 6), remitting MS (n = 45) and remitting NMOSD (n = 23) patients. Significant differences in the levels of site-specific N-glycans on inflammation-associated components [IgM, IgG1, IgG2, complement components 8b (CO8B) and attractin], central nerve system-damage-related serum proteins [apolipoprotein D (APOD), alpha-1-antitrypsin, plasma kallikrein and ADAMTS-like protein 3] were observed among three study groups. We furthered demonstrated that site-specific N-glycans on APOD on site 98, CO8B on sites 243 and 553 are potential markers to differentiate MS from NMOSD with an area under receiver operating curve value > 0.75. All these observations indicate that remitting MS or NMOSD patients possess a unique disease-associated glyco-signature in their serum proteins. We conclude that monitoring one's serum protein glycan profile using this high-throughput analysis may provide an additional diagnostic criterion for differentiating diseases, monitoring disease status and estimating response-to-treatment effect.


Asunto(s)
Esclerosis Múltiple , Neuromielitis Óptica , Biomarcadores , Humanos , Inmunoglobulina G , Esclerosis Múltiple/diagnóstico , Neuromielitis Óptica/diagnóstico , Proyectos Piloto
5.
Glycobiology ; 29(2): 151-162, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30289459

RESUMEN

Galectin-8, a beta-galactoside-binding lectin, is upregulated in the gastric tissues of rhesus macaques infected with Helicobacter pylori. In this study, we found that H. pylori infection triggers intracellular galectin-8 aggregation in human-derived AGS gastric epithelial cells, and that these aggregates colocalize with lysosomes. Notably, this aggregation is markedly reduced following the attenuation of host O-glycan processing. This indicates that H. pylori infection induces lysosomal damage, which in turn results in the accumulation of cytosolic galectin-8 around damaged lysosomes through the recognition of exposed vacuolar host O-glycans. H. pylori-induced galectin-8 aggregates also colocalize with autophagosomes, and galectin-8 ablation reduces the activation of autophagy by H. pylori. This suggests that galectin-8 aggregates may enhance autophagy activity in infected cells. We also observed that both autophagy and NDP52, an autophagy adapter, contribute to the augmentation of galectin-8 aggregation by H. pylori. Additionally, vacuolating cytotoxin A, a secreted H. pylori cytotoxin, may contribute to the increased galectin-8 aggregation and elevated autophagy response in infected cells. Collectively, these results suggest that H. pylori promotes intracellular galectin-8 aggregation, and that galectin-8 aggregation and autophagy may reciprocally regulate each other during infection.


Asunto(s)
Células Epiteliales/metabolismo , Galectinas/metabolismo , Mucosa Gástrica/metabolismo , Helicobacter pylori/metabolismo , Lisosomas/metabolismo , Polisacáridos/metabolismo , Autofagia , Mucosa Gástrica/patología , Humanos , Agregado de Proteínas
6.
Glycobiology ; 30(1): 49-57, 2019 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-31553041

RESUMEN

Galectins are ß-galactoside-binding animal lectins primarily found in the cytosol, while their carbohydrate ligands are mainly distributed in the extracellular space. Cytosolic galectins are anticipated to accumulate on damaged endocytic vesicles through binding to glycans initially displayed on the cell surface and subsequently located in the lumen of the vesicles, and this can be followed by cellular responses. To facilitate elucidation of the mechanism underlying this process, we adopted a model system involving induction of endocytic vesicle damage with light that targets the endocytosed amphiphilic photosensitizer disulfonated aluminum phthalocyanine. We demonstrate that the levels of galectins around damaged endosomes are dependent on the composition of carbohydrates recognized by the proteins. By super resolution imaging, galectin-3 and galectin-8 aggregates were found to be distributed in distinct microcompartments. Importantly, galectin accumulation is significantly affected when cell surface glycans are altered. Furthermore, accumulated galectins can direct autophagy adaptor proteins toward damaged endocytic vesicles, which are also significantly affected following alteration of cell surface glycans. We conclude that cytosolic galectins control cellular responses reflect dynamic modifications of cell surface glycans.


Asunto(s)
Carbohidratos/química , Galectinas/metabolismo , Células A549 , Animales , Células CHO , Comunicación Celular , Células Cultivadas , Cricetulus , Endosomas/metabolismo , Galectinas/química , Humanos
7.
Am J Pathol ; 188(5): 1225-1235, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29458010

RESUMEN

Impairment of the intestinal mucosal immunity significantly increases the risk of acute and chronic diseases. IgA plays a major role in humoral mucosal immunity to provide protection against pathogens and toxins in the gut. Here, we investigated the role of endogenous galectin-9, a tandem repeat-type ß-galactoside-binding protein, in intestinal mucosal immunity. By mucosal immunization of Lgals9-/- and littermate control mice, it was found that lack of galectin-9 impaired mucosal antigen-specific IgA response in the gut. Moreover, Lgals9-/- mice were more susceptible to developing watery diarrhea and more prone to death in response to high-dose cholera toxin. The results indicate the importance of galectin-9 in modulating intestinal adaptive immunity. Furthermore, bone marrow chimera mice were established, and galectin-9 in hematopoietic cells was found to be critical for adaptive IgA response. In addition, immunized Lgals9-/- mice exhibited lower expression of Il17 and fewer T helper 17 (Th17) cells in the lamina propria, implying that the Th17-IgA axis is involved in this mechanism. Taken together, these findings suggest that galectin-9 plays a role in mucosal adaptive immunity through the Th17-IgA axis. By manipulating the expression or activity of galectin-9, intestinal mucosal immune response can be altered and may benefit the development of mucosal vaccination.


Asunto(s)
Inmunidad Adaptativa/fisiología , Galectinas/metabolismo , Inmunoglobulina A/metabolismo , Mucosa Intestinal/metabolismo , Células Th17/metabolismo , Animales , Galectinas/genética , Mucosa Intestinal/inmunología , Ratones , Ratones Noqueados , Células Th17/inmunología
8.
Am J Pathol ; 188(4): 1031-1042, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29366678

RESUMEN

Highly pathogenic avian influenza A H5N1 virus causes pneumonia and acute respiratory distress syndrome in humans. Virus-induced excessive inflammatory response contributes to severe disease and high mortality rates. Galectin-3, a ß-galactoside-binding protein widely distributed in immune and epithelial cells, regulates various immune functions and modulates microbial infections. Here, we describe galectin-3 up-regulation in mouse lung tissue after challenges with the H5N1 influenza virus. We investigated the effects of endogenous galectin-3 on H5N1 infection and found that survival of galectin-3 knockout (Gal-3KO) mice was comparable with wild-type (WT) mice after infections. Compared with infected WT mice, infected Gal-3KO mice exhibited less inflammation in the lungs and reduced IL-1ß levels in bronchoalveolar lavage fluid. In addition, the bone marrow-derived macrophages (BMMs) from Gal-3KO mice exhibited reduced oligomerization of apoptosis-associated speck-like proteins containing caspase-associated recruitment domains and secreted less IL-1ß compared with BMMs from WT mice. However, similar levels of the inflammasome component of nucleotide oligomerization domain-like receptor protein 3 (NLRP3) were observed in two genotypes of BMMs. Co-immunoprecipitation data indicated galectin-3 and NLRP3 interaction in BMMs infected with H5N1. An association was also observed between galectin-3 and NLRP3/apoptosis-associated speck-like proteins containing caspase-associated recruitment domain complex. Combined, our results suggest that endogenous galectin-3 enhances the effects of H5N1 infection by promoting host inflammatory responses and regulating IL-1ß production by macrophages via interaction with NLRP3.


Asunto(s)
Aves/virología , Galectina 3/metabolismo , Subtipo H5N1 del Virus de la Influenza A/fisiología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Neumonía/metabolismo , Neumonía/virología , Animales , Proteínas Adaptadoras de Señalización CARD/metabolismo , Perros , Células HEK293 , Humanos , Interleucina-1beta/metabolismo , Pulmón/patología , Pulmón/virología , Macrófagos/metabolismo , Células de Riñón Canino Madin Darby , Ratones Endogámicos C57BL , Ratones Noqueados , Infecciones por Orthomyxoviridae/metabolismo , Infecciones por Orthomyxoviridae/patología , Infecciones por Orthomyxoviridae/virología , Neumonía/patología , Piroptosis , Análisis de Supervivencia , Regulación hacia Arriba
9.
Glycobiology ; 28(6): 392-405, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29800364

RESUMEN

While glycans are generally displayed on the cell surface or confined within the lumen of organelles, they can become exposed to the cytosolic milieu upon disruption of organelle membrane by various stresses or pathogens. Galectins are a family of ß-galactoside-binding animal lectins synthesized and predominantly localized in the cytosol. Recent research indicates that some galectins may act as "danger signal sensors" by detecting unusual exposure of glycans to the cytosol. Galectin-8 was shown to promote antibacterial autophagy by recognizing host glycans on ruptured vacuolar membranes and interacting with the autophagy adaptor protein NDP52. Galectin-3 also accumulates at damaged phagosomes containing bacteria; however, its functional consequence remains obscure. By studying mouse macrophages infected with Listeria monocytogenes (LM), we showed that endogenous galectin-3 protects intracellular LM by suppressing the autophagic response through a host N-glycan-dependent mechanism. Knock out of the galectin-3 gene resulted in enhanced LC3 recruitment to LM and decreased bacterial replication, a phenotype recapitulated when Galectin-8-deficient macrophages were depleted of N-glycans. Moreover, we explored the concept that alterations in cell surface glycosylation by extracellular factors can be deciphered by cytosolic galectins during the process of phagocytosis/endocytosis, followed by rupture of phagosomal/endosomal membrane. Notably, treatment of cells with sialidase, which removes sialic acid from glycans, resulted in increased galectin-3 accumulation and decreased galectin-8 recruitment at damaged phagosomes, and led to a stronger anti-autophagic response. Our findings demonstrate that cytosolic galectins may sense changes in glycosylation at the cell surface and modulate cellular response through differential recognition of glycans on ruptured phagosomal membranes.


Asunto(s)
Autofagia , Galectina 3/metabolismo , Galectinas/metabolismo , Fagosomas/metabolismo , Polisacáridos/metabolismo , Animales , Línea Celular , Células Cultivadas , Citosol/metabolismo , Galectina 3/genética , Galectinas/genética , Listeria monocytogenes/patogenicidad , Macrófagos/metabolismo , Macrófagos/microbiología , Ratones , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos/metabolismo , Unión Proteica
10.
FASEB J ; 30(12): 4202-4213, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27630169

RESUMEN

Macrophage activation is an important feature of primary biliary cholangitis (PBC) pathogenesis and other cholestatic liver diseases. Galectin-3 (Gal3), a pleiotropic lectin, is produced by monocytic cells and macrophages. However, its role in PBC has not been addressed. We hypothesized that Gal3 is a key to induce NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome in macrophages and in turn to propagate proinflammatory IL-17 signaling. In liver tissues from patients with PBC and dnTGF-ßRII mice, a model of autoimmune cholangitis, the expression of Gal3, NLRP3, and the adaptor protein adaptor apoptosis-associated speck-like protein was induced, with the downstream activation of caspase-1 and IL-1ß. In wild-type hepatic macrophages, deoxycholic acid induced the association of Gal3 and NLRP3 with direct activation of the inflammasome, resulting in an increase in IL-1ß. Downstream retinoid-related orphan receptor C mRNA, IL-17A, and IL-17F were induced. In Gal3-/- macrophages, no inflammasome activation was detected. To confirm the key role of Gal3 in the pathogenesis of cholestatic liver injury, we generated dnTGF-ßRII/galectin-3-/- (dn/Gal3-/-) mice, which showed impaired inflammasome activation along with significantly improved inflammation and fibrosis. Taken together, our data point to a novel role of Gal3 as an initiator of inflammatory signaling in autoimmune cholangitis, mediating the activation of NLRP3 inflammasome and inducing IL-17 proinflammatory cascades. These studies provide a rationale to target Gal3 in autoimmune cholangitis and potentially other cholestatic diseases.-Tian, J., Yang, G., Chen, H.-Y., Hsu, D. K., Tomilov, A., Olson, K. A., Dehnad, A., Fish, S. R., Cortopassi, G., Zhao, B., Liu, F.-T., Gershwin, M. E., Török, N. J., Jiang, J. X. Galectin-3 regulates inflammasome activation in cholestatic liver injury.


Asunto(s)
Galectina 3/metabolismo , Inflamasomas/metabolismo , Hígado/metabolismo , Macrófagos/metabolismo , Transducción de Señal/fisiología , Animales , Caspasa 1/metabolismo , Células Cultivadas , Galectina 3/genética , Humanos , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Hígado/lesiones , Activación de Macrófagos/fisiología , Ratones Transgénicos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo
11.
J Immunol ; 195(8): 3912-21, 2015 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-26371257

RESUMEN

Activation of TLR7-9 has been linked to the pathogenesis of autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and psoriasis. Thus, therapeutic applications of antagonists of these TLRs for such disorders are being investigated. Bortezomib (Velcade) is a proteasome inhibitor known to suppress activation of these TLRs. To identify novel TLR7-9 inhibitors, we searched the Gene Expression Omnibus database for gene expression profiles of bortezomib-treated cells. These profiles were then used to screen the Connectivity Map database for chemical compounds with similar functions as bortezomib. A natural antibiotic, thiostrepton, was identified for study. Similar to bortezomib, thiostrepton effectively inhibits TLR7-9 activation in cell-based assays and in dendritic cells. In contrast to bortezomib, thiostrepton does not inhibit NF-κB activation induced by TNF-α, IL-1, and other TLRs, and it is less cytotoxic to dendritic cells. Thiostrepton inhibits TLR9 localization in endosomes for activation via two mechanisms, which distinguish it from currently used TLR7-9 inhibitors. One mechanism is similar to the proteasome inhibitory function of bortezomib, whereas the other is through inhibition of endosomal acidification. Accordingly, in different animal models, thiostrepton attenuated LL37- and imiquimod-induced psoriasis-like inflammation. These results indicated that thiostrepton is a novel TLR7-9 inhibitor, and compared with bortezomib, its inhibitory effect is more specific to these TLRs, suggesting the potential therapeutic applications of thiostrepton on immunologic disorders elicited by inappropriate activation of TLR7-9.


Asunto(s)
Glicoproteínas de Membrana/antagonistas & inhibidores , Psoriasis/tratamiento farmacológico , Tioestreptona/farmacología , Receptor Toll-Like 7/antagonistas & inhibidores , Receptor Toll-Like 9/antagonistas & inhibidores , Animales , Línea Celular , Humanos , Inflamación/inmunología , Inflamación/patología , Interleucina-1/inmunología , Glicoproteínas de Membrana/inmunología , Ratones , Psoriasis/inmunología , Psoriasis/patología , Receptor Toll-Like 7/inmunología , Receptor Toll-Like 9/inmunología , Factor de Necrosis Tumoral alfa/inmunología
12.
Sensors (Basel) ; 17(10)2017 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-28956859

RESUMEN

This study aims to present an effective VLSI circuit for multi-channel spike sorting. The circuit supports the spike detection, feature extraction and classification operations. The detection circuit is implemented in accordance with the nonlinear energy operator algorithm. Both the peak detection and area computation operations are adopted for the realization of the hardware architecture for feature extraction. The resulting feature vectors are classified by a circuit for competitive learning (CL) neural networks. The CL circuit supports both online training and classification. In the proposed architecture, all the channels share the same detection, feature extraction, learning and classification circuits for a low area cost hardware implementation. The clock-gating technique is also employed for reducing the power dissipation. To evaluate the performance of the architecture, an application-specific integrated circuit (ASIC) implementation is presented. Experimental results demonstrate that the proposed circuit exhibits the advantages of a low chip area, a low power dissipation and a high classification success rate for spike sorting.

13.
Blood ; 121(16): 3172-80, 2013 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-23449638

RESUMEN

Alterations of galectin-3 expression are often seen in cancers and may contribute to tumorigenesis, cancer progression, and metastasis. The studies concerning clinical implications of galectin-3 expression in patients with acute myeloid leukemia (AML) are scarce. We investigated the expression of LGALS3, the gene encoding galectin-3, in the bone marrow (BM) mononuclear cells from an original cohort comprising 280 adults with primary non-acute promyelocytic leukemia. Higher LGALS3 expression was closely associated with older age, French-American-British M4/M5 subtypes, CD14 expression on leukemic cells, and PTPN11 mutation, but negatively correlated with CEBPA mutation and FLT3-ITD. Compared with patients with lower LGALS3 expression, those with higher expression had lower complete remission rates, higher primary refractory rates, and shorter overall survival. This result was validated in an independent validation cohort. A scoring system incorporating higher LGALS3 expression and 8 other risk factors, including age, white blood cell count, cytogenetics, and gene mutations, into survival analysis proved to be very useful to stratify patients with AML into different prognostic groups (P < .001). In conclusion, BM LGALS3 expression may serve as a new biomarker to predict clinical outcome in patients with AML, and galectin-3 may serve as a potential therapeutic target in those patients with higher expression of this protein.


Asunto(s)
Médula Ósea/patología , Galectina 3/genética , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Médula Ósea/metabolismo , Estudios de Cohortes , Femenino , Expresión Génica , Humanos , Cariotipo , Leucemia Mieloide Aguda/patología , Leucemia Mieloide Aguda/terapia , Masculino , Persona de Mediana Edad , Mutación , Pronóstico , ARN/genética , Análisis de Supervivencia , Resultado del Tratamiento , Regulación hacia Arriba , Adulto Joven
14.
Appl Opt ; 54(1): A67-75, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25967024

RESUMEN

This work presents a novel hardware phase-unwrapping architecture for digital holographic microscopy. The architecture is based on an iterative region-referenced algorithm because of its simplicity and effectiveness for phase unwrapping. The architecture therefore consumes fewer hardware resources for very large-scale integration implementation. In addition, a novel data reuse scheme is adopted for reducing the memory bandwidth required by the architecture. The architecture can then have fast computation speed for the iterative operations. The architecture has been implemented by field programmable gate array. It acts as a hardware accelerator in an embedded system developed by a network-on-chip platform for performance measurement. The superiorities of the proposed architecture have been confirmed by the experiments.

15.
Glycobiology ; 24(11): 1022-35, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24996823

RESUMEN

Galectin-3 has been reported to regulate the functions of a number of immune cell types. We previously reported that galectin-3 is translocated to immunological synapses in T cells upon T-cell receptor engagement, where it associates with ALG-2-interacting protein X (Alix). Alix is known to coordinate with the endosomal sorting complex required for transport (ESCRT) to promote human immunodeficiency virus (HIV)-1 virion release. We hypothesized that galectin-3 plays a role in HIV-1 viral budding. Cotransfection of cells of the Jurkat T line with galectin-3 and HIV-1 plasmids resulted in increased HIV-1 budding, and suppression of galectin-3 expression by RNAi in Hut78 and primary CD4+ T cells led to reduced HIV-1 budding. We used immunofluorescence microscopy to observe the partial colocalization of galectin-3, Alix and Gag in HIV-1-infected cells. Results from co-immunoprecipitation experiments indicate that galectin-3 expression promotes Alix-Gag p6 association, whereas the results of Alix knockdown suggest that galectin-3 promotes HIV-1 budding through Alix. HIV-1 particles released from galectin-3-expressing cells acquire the galectin-3 protein in an Alix-dependent manner, with proteins primarily residing inside the virions. We also found that the galectin-3 N-terminal domain interacts with the proline-rich region of Alix. Collectively, these results suggest that endogenous galectin-3 facilitates HIV-1 budding by promoting the Alix-Gag p6 association.


Asunto(s)
Proteínas de Unión al Calcio/fisiología , Proteínas de Ciclo Celular/fisiología , Complejos de Clasificación Endosomal Requeridos para el Transporte/fisiología , Galectina 3/fisiología , VIH-1/fisiología , Replicación Viral/fisiología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/fisiología , Unión Proteica
16.
Am J Pathol ; 183(4): 1209-1222, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23916470

RESUMEN

Galectin-3 is a ß-galactoside-binding animal lectin with diverse functions, including regulation of T helper (Th) 1 and Th2 responses. Current data indicate that galectin-3 expressed in dendritic cells (DCs) may be contributory. Th17 cells have emerged as critical inducers of tissue inflammation in autoimmune disease and important mediators of host defense against fungal pathogens, although little is known about galectin-3 involvement in Th17 development. We investigated the role of galectin-3 in the induction of Th17 immunity in galectin-3-deficient (gal3(-/-)) and gal3(+/+) mouse bone marrow-derived DCs. We demonstrate that intracellular galectin-3 negatively regulates Th17 polarization in response to the dectin-1 agonist curdlan (a ß-glucan present on the cell wall of fungal species) and lipopolysaccharide, agents that prime DCs for Th17 differentiation. On activation of dectin-1, gal3(-/-) DCs secreted higher levels of the Th17-axis cytokine IL-23 compared with gal3(+/+) DCs and contained higher levels of activated c-Rel, an NF-κB subunit that promotes IL-23 expression. Levels of active Raf-1, a kinase that participates in downstream inhibition of c-Rel binding to the IL23A promoter, were impaired in gal3(-/-) DCs. Modulation of Th17 by galectin-3 in DCs also occurred in vivo because adoptive transfer of gal3(-/-) DCs exposed to Candida albicans conferred higher Th17 responses and protection against fungal infection. We conclude that galectin-3 suppresses Th17 responses by regulating DC cytokine production.


Asunto(s)
Citocinas/metabolismo , Células Dendríticas/metabolismo , Galectina 3/metabolismo , Células Th17/inmunología , Traslado Adoptivo , Animales , Candida albicans/inmunología , Candida albicans/fisiología , Candidiasis/inmunología , Candidiasis/microbiología , Candidiasis/patología , Polaridad Celular/efectos de los fármacos , Pollos , Células Dendríticas/efectos de los fármacos , Células Dendríticas/enzimología , Células Dendríticas/microbiología , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Galectina 3/deficiencia , Inmunidad/efectos de los fármacos , Interleucina-23/biosíntesis , Lectinas Tipo C/agonistas , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos C57BL , Modelos Biológicos , Proteínas Proto-Oncogénicas c-raf/metabolismo , Proteínas Proto-Oncogénicas c-rel/metabolismo , Transducción de Señal/efectos de los fármacos , Células Th17/efectos de los fármacos , beta-Glucanos/farmacología
17.
Immunol Rev ; 230(1): 114-27, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19594632

RESUMEN

Galectin-3 is absent in resting CD4+ and CD8+ T cells but is inducible by various stimuli. These include viral transactivating factors, T-cell receptor (TCR) ligation, and calcium ionophores. In addition, galectin-3 is constitutively expressed in human regulatory T cells and CD4+ memory T cells. Galectin-3 exerts extracellular functions because of its lectin activity and recognition of cell surface and extracellular matrix glycans. These include cell activation, adhesion, induction of apoptosis, and formation of lattices with cell surface glycoprotein receptors. Formation of lattices can result in restriction of receptor mobility and cause attenuation of receptor functions. Consistent with the presence of galectin-3 in intracellular locations, several functions have been described for this protein inside T cells. These include inhibition of apoptosis, promotion of cell growth, and regulation of TCR signal transduction. Studies of cell surface glycosylation have led to convergence of glycobiology and galectin biology and provided new clues on how galectin-3 may participate in the regulation of cell surface receptor activities. The rapid expansion of the field of galectin research has positioned galectin-3 as a key regulator in T-cell functions.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Citocinas/inmunología , Galectina 3/inmunología , Subgrupos de Linfocitos T/inmunología , Animales , Apoptosis/inmunología , Enfermedades Autoinmunes/metabolismo , Adhesión Celular/inmunología , Citocinas/metabolismo , Galectina 3/metabolismo , Glicosilación , Humanos , Activación de Linfocitos/inmunología , Transducción de Señal/inmunología , Subgrupos de Linfocitos T/metabolismo
18.
Neurobiol Stress ; 26: 100554, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37576348

RESUMEN

Posttraumatic stress disorder (PTSD) is a complex syndrome that may occur after life-threatening events. Fear memory abnormalities may play vital roles in the pathogenesis of PTSD. Previous work has found that fear memories are not rigid; the retrieval of fear memories may change over time. Furthermore, prior studies suggest that theta wave (4 Hz) activity is highly correlated with fear expression in an animal model. However, the relationship between pathological fear memory and potential brain wave features in PTSD remains largely uncharacterized. Here, we hypothesized that after traumatic stress exposure, the longitudinal dynamics of abnormal fears in PTSD animal models could be reflected by the measurement of local field potentials (LFPs). Using a well-established modified single-prolonged stress and footshock (SPS & FS) PTSD rat model, animals were restrained for 2 h and subsequently subjected to 20 min of forced swimming, then exposed to diethyl ether until they lost consciousness and placed in a conditioning chamber for fear conditioning. To characterize the temporal changes, we characterized freezing behavior brain wave features during the conditioning chamber re-exposure in the early (10 and 30 min; 2, 4, and 6 h) and late (day 1, 3, 7, and 14) phases after traumatic stress exposure. Our results indicate that SPS & FS rats showed co-morbid PTSD phenotypes including significantly higher levels of anxiety-, depression-, and anhedonia-like behaviors, and impaired fear extinction. Delta wave (0.5-4 Hz) suppression in the medial prefrontal cortex, amygdala, and ventral hippocampus occurred 10 and 30 min after traumatic stress, followed by continuous delta wave activity from 2 h to day 14, correlating with fear levels. tDCS reduced delta activity and alleviated PTSD-like phenotypes in the SPS & FS group. In this study, profiling abnormal fears with brain wave correlates may improve our understanding of time-dependent pathological fear memory retrieval in PTSD and facilitate the development of effective intervention strategies.

19.
J Vis Exp ; (193)2023 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-37010300

RESUMEN

Intracellular vesicles (IVs) are formed through endocytosis of vesicles into cytoplasm. IV formation is involved in activating various signal pathways through permeabilization of IV membranes and the formation of endosomes and lysosomes. A method named chromophore-assisted laser inactivation (CALI) is applied to study the formation of IVs and the materials in controlling IV regulation. CALI is an imaging-based photodynamic methodology to study the signaling pathway induced by membrane permeabilization. The method allows spatiotemporal manipulation of the selected organelle to be permeabilized in a cell. The CALI method has been applied to observe and monitor specific molecules through the permeabilization of endosomes and lysosomes. The membrane rupture of IVs is known to selectively recruit glycan-binding proteins, such as galectin-3. Here, the protocol describes the induction of IV rupture by AlPcS2a and the use of galectin-3 as a marker to label impaired lysosomes, which is useful in studying the downstream effects of IV membrane rupture and their downstream effects under various situations.


Asunto(s)
Endosomas , Galectina 3 , Galectina 3/metabolismo , Endosomas/metabolismo , Endocitosis/fisiología , Lisosomas/metabolismo , Transducción de Señal , Membranas Intracelulares/metabolismo
20.
Neurobiol Stress ; 27: 100569, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37771408

RESUMEN

Posttraumatic stress disorder (PTSD) is a complex disorder that involves physiological, emotional, and cognitive dysregulation that may occur after exposure to a life-threatening event. In contrast with the condition of learned fear with resilience to extinction, abnormal fear with impaired fear extinction and exaggeration are considered crucial factors for the pathological development of PTSD. The prefrontal cortex (mPFC) is considered a critical region of top-down control in fear regulation, which involves the modulation of fear expression and extinction. The pathological course of PTSD is usually chronic and persistent; a number of studies have indicated temporal progression in gene expression and phenotypes may be involved in PTSD pathology. In the current study, we use a well-established modified single-prolonged stress (SPS&FS) rat model to feature PTSD-like phenotypes and compared it with a footshock fear conditioning model (FS model); we collected the frontal tissue after extreme stress exposure or fear conditioning and extracted RNA for transcriptome-level gene sequencing. We compared the genetic profiling of the mPFC at early (<2 h after solely FS or SPS&FS exposure) and late (7 days after solely FS or SPS&FS exposure) stages in these two models. First, we identified temporal differences in the expressional patterns between these two models and found pathways such as protein synthesis factor eukaryotic initiation factor 2 (EIF2), transcription factor NF-E2-related factor 2 (NRF2)-mediated oxidative stress response, and acute phase responding signaling enriched in the early stage in both models with significant p-values. Furthermore, in the late stage, the sirtuin signaling pathway was enriched in both models; other pathways such as STAT3, cAMP, lipid metabolism, Gα signaling, and increased fear were especially enriched in the late stage of the SPS&FS model. However, pathways such as VDR/RXR, GP6, and PPAR signaling were activated significantly in the FS model's late stage. Last, the network analysis revealed the temporal dynamics of psychological disorder, the endocrine system, and also genes related to increased fear in the two models. This study could help elucidate the genetic temporal alteration and stage-specific pathways in these two models, as well as a better understanding of the transcriptome-level differences between them.

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