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1.
Nat Immunol ; 22(2): 154-165, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33398185

RESUMEN

Inflammatory caspase sensing of cytosolic lipopolysaccharide (LPS) triggers pyroptosis and the concurrent release of damage-associated molecular patterns (DAMPs). Collectively, DAMPs are key determinants that shape the aftermath of inflammatory cell death. However, the identity and function of the individual DAMPs released are poorly defined. Our proteomics study revealed that cytosolic LPS sensing triggered the release of galectin-1, a ß-galactoside-binding lectin. Galectin-1 release is a common feature of inflammatory cell death, including necroptosis. In vivo studies using galectin-1-deficient mice, recombinant galectin-1 and galectin-1-neutralizing antibody showed that galectin-1 promotes inflammation and plays a detrimental role in LPS-induced lethality. Mechanistically, galectin-1 inhibition of CD45 (Ptprc) underlies its unfavorable role in endotoxin shock. Finally, we found increased galectin-1 in sera from human patients with sepsis. Overall, we uncovered galectin-1 as a bona fide DAMP released as a consequence of cytosolic LPS sensing, identifying a new outcome of inflammatory cell death.


Asunto(s)
Alarminas/metabolismo , Endotoxemia/inmunología , Galectina 1/metabolismo , Mediadores de Inflamación/metabolismo , Inflamación/inmunología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Macrófagos/metabolismo , Proteínas de Unión a Fosfato/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Alarminas/deficiencia , Alarminas/genética , Animales , Estudios de Casos y Controles , Modelos Animales de Enfermedad , Endotoxemia/inducido químicamente , Endotoxemia/metabolismo , Endotoxemia/patología , Femenino , Galectina 1/sangre , Galectina 1/deficiencia , Galectina 1/genética , Células HeLa , Humanos , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Péptidos y Proteínas de Señalización Intracelular/genética , Antígenos Comunes de Leucocito/metabolismo , Lipopolisacáridos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Necroptosis , Proteínas de Unión a Fosfato/deficiencia , Proteínas de Unión a Fosfato/genética , Células RAW 264.7 , Sepsis/sangre , Sepsis/diagnóstico , Transducción de Señal , Regulación hacia Arriba
2.
Cell ; 162(6): 1338-52, 2015 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-26359987

RESUMEN

Seasonal changes in disease activity have been observed in multiple sclerosis, an autoimmune disorder that affects the CNS. These epidemiological observations suggest that environmental factors influence the disease course. Here, we report that melatonin levels, whose production is modulated by seasonal variations in night length, negatively correlate with multiple sclerosis activity in humans. Treatment with melatonin ameliorates disease in an experimental model of multiple sclerosis and directly interferes with the differentiation of human and mouse T cells. Melatonin induces the expression of the repressor transcription factor Nfil3, blocking the differentiation of pathogenic Th17 cells and boosts the generation of protective Tr1 cells via Erk1/2 and the transactivation of the IL-10 promoter by ROR-α. These results suggest that melatonin is another example of how environmental-driven cues can impact T cell differentiation and have implications for autoimmune disorders such as multiple sclerosis.


Asunto(s)
Melatonina/metabolismo , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Diferenciación Celular , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Femenino , Humanos , Luz , Sistema de Señalización de MAP Quinasas , Masculino , Ratones , Ratones Endogámicos C57BL , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Recurrencia , Estaciones del Año , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células Th17/citología , Células Th17/inmunología , Células Th17/metabolismo
3.
Cell ; 156(4): 744-58, 2014 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-24529377

RESUMEN

The clinical benefit conferred by vascular endothelial growth factors (VEGF)-targeted therapies is variable, and tumors from treated patients eventually reinitiate growth. Here, we identify a glycosylation-dependent pathway that compensates for the absence of cognate ligand and preserves angiogenesis in response to VEGF blockade. Remodeling of the endothelial cell (EC) surface glycome selectively regulated binding of galectin-1 (Gal1), which upon recognition of complex N-glycans on VEGFR2, activated VEGF-like signaling. Vessels within anti-VEGF-sensitive tumors exhibited high levels of α2-6-linked sialic acid, which prevented Gal1 binding. In contrast, anti-VEGF refractory tumors secreted increased Gal1 and their associated vasculature displayed glycosylation patterns that facilitated Gal1-EC interactions. Interruption of ß1-6GlcNAc branching in ECs or silencing of tumor-derived Gal1 converted refractory into anti-VEGF-sensitive tumors, whereas elimination of α2-6-linked sialic acid conferred resistance to anti-VEGF. Disruption of the Gal1-N-glycan axis promoted vascular remodeling, immune cell influx and tumor growth inhibition. Thus, targeting glycosylation-dependent lectin-receptor interactions may increase the efficacy of anti-VEGF treatment.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Neoplasias/irrigación sanguínea , Neoplasias/tratamiento farmacológico , Neovascularización Patológica , Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Células Endoteliales/metabolismo , Galectina 1/genética , Galectina 1/metabolismo , Glicosilación , Humanos , Hipoxia , Ratones , Receptores Mitogénicos/metabolismo
4.
FASEB J ; 37(4): e22865, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36934391

RESUMEN

Hypothyroidism exerts deleterious effects on immunity, but the precise role of the hypothalamic-pituitary-thyroid (HPT) axis in immunoregulatory and tolerogenic programs is barely understood. Here, we investigated the mechanisms underlying hypothyroid-related immunosuppression by examining the regulatory role of components of the HPT axis. We first analyzed lymphocyte activity in mice overexpressing the TRH gene (Tg-Trh). T cells from Tg-Trh showed increased proliferation than wild-type (WT) euthyroid mice in response to polyclonal activation. The release of Th1 pro-inflammatory cytokines was also increased in Tg-Trh and TSH levels correlated with T-cell proliferation. To gain further mechanistic insights into hypothyroidism-related immunosuppression, we evaluated T-cell subpopulations in lymphoid tissues of hypothyroid and control mice. No differences were observed in CD3/CD19 or CD4/CD8 ratios between these strains. However, the frequency of regulatory T cells (Tregs) was significantly increased in hypothyroid mice, and not in Tg-Trh mice. Accordingly, in vitro Tregs differentiation was more pronounced in naïve T cells isolated from hypothyroid mice. Since Tregs overexpress galectin-1 (Gal-1) and mice lacking this lectin (Lgals1-/- ) show reduced Treg function, we investigated the involvement of this immunoregulatory lectin in the control of Tregs in settings of hypothyroidism. Increased T lymphocyte reactivity and reduced frequency of Tregs were found in hypothyroid Lgals1-/- mice when compared to hypothyroid WT animals. This effect was rescued by the addition of recombinant Gal-1. Finally, increased expression of Gal-1 was found in Tregs purified from hypothyroid WT mice compared with their euthyroid counterpart. Thus, a substantial increase in the frequency and activity of Gal-1-expressing Tregs underlies immunosuppression associated with hypothyroid conditions, with critical implications in immunopathology, metabolic disorders, and cancer.


Asunto(s)
Hipotiroidismo , Tirotropina , Ratones , Animales , Tirotropina/metabolismo , Hormona Liberadora de Tirotropina/farmacología , Linfocitos T Reguladores/metabolismo , Galectina 1/genética , Hipotiroidismo/metabolismo , Terapia de Inmunosupresión
5.
Mar Drugs ; 22(3)2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38535446

RESUMEN

The presence of bioactive compounds in European eel (Anguilla anguilla) skin was studied. Proximate and lipid class compositions and analysis of the fatty acid (FA) profile (individual FAs; FA groups, i.e., saturated, monounsaturated, and polyunsaturated; FA ratios, i.e., polyunsaturated/saturated, ω3/ω6) were determined and compared to the composition of the eel muscle. As a result, higher (p < 0.05) levels of proteins (271.6 g·kg-1), lipids (38.0 g·kg-1), ash (27.7 g·kg-1), and ω6 FAs were observed in the skin tissue. Contrary, the muscle tissue showed higher (p < 0.05) moisture, ω3 FA, and ω3/ω6 ratio values. Regarding lipid classes, a higher (p < 0.05) proportion of phospholipids (111.1 g·kg-1 lipids), free sterols (104.7 g·kg-1 lipids), α-tocopherol (274.0 mg·kg-1 lipids), and free FAs (43.6 g·kg-1 lipids) was observed in the skin tissue. No differences (p > 0.05) between both tissues could be detected for triacylglycerol and FA group (saturated, monounsaturated, and polyunsaturated) values and for the polyunsaturated/saturated FA ratio. It is concluded that European eel skin, a by-product resulting from commercial processing, can be considered a valuable source for the food and pharmaceutical industries by providing value-added constituents such as proteins, lipids, ω3 FAs, phospholipids, and α-tocopherol.


Asunto(s)
Anguilla , Animales , alfa-Tocoferol , Alimentos Marinos , Piel , Ácidos Grasos , Fosfolípidos
6.
Proc Natl Acad Sci U S A ; 117(7): 3693-3703, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-32019882

RESUMEN

Glioblastoma is the most aggressive brain malignancy, for which immunotherapy has failed to prolong survival. Glioblastoma-associated immune infiltrates are dominated by tumor-associated macrophages and microglia (TAMs), which are key mediators of immune suppression and resistance to immunotherapy. We and others demonstrated aberrant expression of glycans in different cancer types. These tumor-associated glycans trigger inhibitory signaling in TAMs through glycan-binding receptors. We investigated the glioblastoma glycocalyx as a tumor-intrinsic immune suppressor. We detected increased expression of both tumor-associated truncated O-linked glycans and their receptor, macrophage galactose-type lectin (MGL), on CD163+ TAMs in glioblastoma patient-derived tumor tissues. In an immunocompetent orthotopic glioma mouse model overexpressing truncated O-linked glycans (MGL ligands), high-dimensional mass cytometry revealed a wide heterogeneity of infiltrating myeloid cells with increased infiltration of PD-L1+ TAMs as well as distant alterations in the bone marrow (BM). Our results demonstrate that glioblastomas exploit cell surface O-linked glycans for local and distant immune modulation.


Asunto(s)
Asialoglicoproteínas/inmunología , Glioblastoma/inmunología , Lectinas Tipo C/inmunología , Proteínas de la Membrana/inmunología , Animales , Antígenos CD/genética , Antígenos CD/inmunología , Antígenos de Diferenciación Mielomonocítica/genética , Antígenos de Diferenciación Mielomonocítica/inmunología , Asialoglicoproteínas/química , Asialoglicoproteínas/genética , Glioblastoma/genética , Humanos , Lectinas Tipo C/química , Lectinas Tipo C/genética , Macrófagos/inmunología , Masculino , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Microglía/inmunología , Polisacáridos/química , Polisacáridos/inmunología , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/inmunología
7.
Development ; 146(5)2019 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-30770393

RESUMEN

During neocortical development, neurons are produced by a diverse pool of neural progenitors. A subset of progenitors express the Cux2 gene and are fate restricted to produce certain neuronal subtypes; however, the upstream pathways that specify these progenitor fates remain unknown. To uncover the transcriptional networks that regulate Cux2 expression in the forebrain, we characterized a conserved Cux2 enhancer that recapitulates Cux2 expression specifically in the cortical hem. Using a bioinformatic approach, we identified putative transcription factor (TF)-binding sites for cortical hem-patterning TFs. We found that the homeobox TF Lmx1a can activate the Cux2 enhancer in vitro Furthermore, we showed that Lmx1a-binding sites were required for enhancer activity in the cortical hem in vivo Mis-expression of Lmx1a in hippocampal progenitors caused an increase in Cux2 enhancer activity outside the cortical hem. Finally, we compared several human enhancers with cortical hem-restricted activity and found that recurrent Lmx1a-binding sites are a top shared feature. Uncovering the network of TFs involved in regulating Cux2 expression will increase our understanding of the mechanisms pivotal in establishing Cux2 lineage fates in the developing forebrain.


Asunto(s)
Elementos de Facilitación Genéticos , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/fisiología , Intrones , Proteínas con Homeodominio LIM/fisiología , Factores de Transcripción/fisiología , Animales , Sitios de Unión , Linaje de la Célula , Biología Computacional , Femenino , Proteínas de Homeodominio/genética , Proteínas con Homeodominio LIM/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Prosencéfalo/embriología , Telencéfalo/embriología , Factores de Transcripción/genética
8.
Mar Drugs ; 20(11)2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36354989

RESUMEN

This study addressed the fatty acid (FA) composition of canned Atlantic mackerel (Scomber scombrus). In it, the effect of prior frozen storage (6 months at −18 °C), different packing media (water, brine, and sunflower, refined and extra virgin olive oils), and canning procedure was investigated. As a result, the canning procedure led to a decrease (p < 0.05) in saturated FA (STFA) levels, an increase (p < 0.05) in polyunsaturated FA (PUFA) and total ω3 FA values, and higher PUFA/STFA and ω3/ω6 ratio values. Concerning the packing medium effect, the great presence of C18:2ω6 in sunflower oil led to high PUFA and PUFA/STFA values and low ω3/ω6 ratios when compared to other packing media. However, the high presence of C18:1ω9 in both olive oils tested did not lead to remarkable increases (p > 0.05) of this FA presence. Additionally, the presence of total ω3 FAs, C20:5ω3 and C22:6ω3 did not provide differences in canned fish muscle as a result of using different packing media. In all canned samples, ω3/ω6 values were included in the 8.2−10.8 range. Prior frozen storage did not have a substantial effect (p > 0.05) on the FA group (STFA, monounsaturated FA, PUFA, total ω3 FA) and FA ratio (PUFA/STFA and ω3/ω6) values.


Asunto(s)
Ácidos Grasos Omega-3 , Perciformes , Animales , Ácidos Grasos , Ácidos Grasos Insaturados
9.
Molecules ; 27(3)2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35164004

RESUMEN

The preservative properties of waste liquor obtained from octopus (Octopus vulgaris) cooking were investigated. Three different concentrations (high, medium, and low) of octopus cooking liquor (OCL) were included, respectively, in the aqueous packaging medium employed for mackerel (Scomber colias) canning. As a result, the canning process led to an increase (p < 0.05) of lipid content, lipid oxidation (development of fluorescent compounds and thiobarbituric acid reactive substances, TBARS), lipid hydrolysis (formation of free fatty acids, FFA) and ω3/ω6 ratio in fish muscle. In all canned samples, primary (peroxides) and secondary (TBARS) levels of lipid oxidation were low. Remarkably, the presence in the packaging medium of the high and medium OCL concentrations led to lower (p < 0.05) lipid oxidation development (fluorescent compound and TBARS detection, respectively). Furthermore, an increasing OCL presence led to an average decrease of peroxide and FFA content and to an average increase of the polyene index (PI). All OCL-packaged muscle showed lower average values of saturated fatty acids and ω3/ω6 ratio and higher average values of PI and monounsaturated fatty acid presence. This study provides a first approach to novel and beneficial use of the present marine waste to inhibit lipid damage of commercial canned fish.


Asunto(s)
Embalaje de Alimentos/métodos , Conservación de Alimentos/métodos , Alimentos en Conserva , Octopodiformes/química , Perciformes , Animales , Culinaria , Grasas de la Dieta/metabolismo , Ácidos Grasos no Esterificados/metabolismo , Ácidos Grasos Omega-3/metabolismo , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Oxidación-Reducción , Perciformes/metabolismo , Alimentos Marinos , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
10.
Angiogenesis ; 24(1): 1-5, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33006019

RESUMEN

Galectins, a family of highly conserved ß-galactoside-binding proteins, control tumor progression by modulating different hallmarks of cancer. Galectin-1 (Gal-1), a proto-type member of this family, plays essential roles in tumor angiogenesis and immunosuppression by cross-linking glycosylated receptors on the surface of endothelial and immune cells. Targeted disruption of Gal-1 suppresses tumor growth by counteracting aberrant angiogenesis and reinforcing antitumor immunity in several experimental settings. Given the multiple therapeutic benefits associated with Gal-1 blockade, several Gal-1 inhibitors, including glycan-based competitors, antagonistic peptides, aptamers and neutralizing monoclonal antibodies, have been designed and evaluated in pre-clinical tumor models. Here we report the biochemical and functional characterization of a newly developed neutralizing anti-human Gal-1 monoclonal antibody (Gal-1-mAb3), which specifically recognizes a unique epitope in Gal-1 protein and exerts both angioregulatory and immunomodulatory activities. Blockade of Gal-1 function using Gal-1-mAb3, might be relevant not only in cancer but also in other pathologic conditions characterized by aberrant angiogenesis and uncontrolled immunosuppression.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Anticuerpos Neutralizantes/farmacología , Galectina 1/inmunología , Factores Inmunológicos/farmacología , Neovascularización Fisiológica , Animales , Fenómenos Biofísicos , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Ratones Endogámicos BALB C , Neovascularización Fisiológica/efectos de los fármacos
11.
Mar Drugs ; 19(11)2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34822487

RESUMEN

Green extraction was applied to Argentinean shortfin squid (Illex argentinus) viscera, consisting of a wet pressing method including a drying step, mechanic pressing, centrifugation of the resulting slurry, and oil collection. To maximise the oil yield and ω3 fatty acid content and to minimise the oil damage degree, a response surface methodology (RSM) design was developed focused on the drying temperature (45-85 °C) and time (30-90 min). In general, an increase of the drying time and temperature provided an increase in the lipid yield recovery from the viscera. The strongest drying conditions showed a higher recovery than 50% when compared with the traditional chemical method. The docosahexaenoic and eicosapentaenoic acid contents in the extracted oil revealed scarce dependence on drying conditions, showing valuable ranges (149.2-166.5 and 88.7-102.4 g·kg-1 oil, respectively). Furthermore, the values of free fatty acids, peroxides, conjugated dienes, and ω3/ω6 ratio did not show extensive differences by comparing oils obtained from the different drying conditions. Contrary, a polyene index (PI) decrease was detected with increasing drying time and temperature. The RSM analysis indicated that optimised drying time (41.3 min) and temperature (85 °C) conditions would lead to 74.73 g·kg-1 (oil yield), 1.87 (PI), and 6.72 (peroxide value) scores, with a 0.67 desirability value.


Asunto(s)
Decapodiformes , Ácidos Grasos Omega-3/química , Animales , Organismos Acuáticos , Tecnología Química Verde , Vísceras/química
12.
Molecules ; 26(12)2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34205746

RESUMEN

This work addressed the preservative behaviour of different icing media containing extracts from the alga Bifurcaria bifurcata. A comparative study of the antimicrobial and antioxidant effects of aqueous and ethanolic extracts of this macroalga was carried out. Whole hake (Merluccius merluccius) pieces were stored in ice containing either kind of extract and analysed for quality changes throughout a 13-day storage period. A progressive loss of microbial and biochemical quality was detected in all batches as chilling time increased. A significant inhibitory effect (p < 0.05) on microbial activity could be observed as a result of including the aqueous (lowering of psychrotrophic and lipolytic counts and pH value) and ethanolic (lowering of psychrotrophic and lipolytic counts) extracts. Additionally, both kinds of extract led to a substantial inhibition (p < 0.05) in the lipid hydrolysis rate (formation of free fatty acids), greater in the case of the batch containing ethanolic extract. Concerning lipid oxidation, a similar inhibitory effect (p < 0.05) on the formation of secondary compounds (thiobarbituric acid substances) was noticed in fish specimens corresponding to both alga extracts; however, more (p < 0.05) peroxide formation was detected in fish corresponding to the ethanolic extract batch. A preservative effect can be concluded for both kinds of extract; this effect agrees with previous studies reporting the presence of hydrophilic and lipophilic bioactive compounds in B. bifurcata.


Asunto(s)
Productos Biológicos/farmacología , Conservantes de Alimentos/farmacología , Phaeophyceae/efectos de los fármacos , Algas Marinas/química , Animales , Antioxidantes/farmacología , Productos Biológicos/química , Etanol/química , Peces , Conservación de Alimentos/métodos , Gadiformes , Oxidación-Reducción/efectos de los fármacos , Alimentos Marinos , Agua/química
13.
Molecules ; 26(11)2021 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-34067234

RESUMEN

There is consistent evidence that long-chain polyunsaturated fatty acids (LCPUFA) belonging to the n-3 series, i.e., eicosapentaenoic (20:5n-3, EPA) and docosahexaenoic (22:6n-3, DHA) acids, decrease the risk of heart, circulatory and inflammatory diseases. Furthermore, the bioavailability of such fatty acids has been shown to depend on their location in triacylglycerol (TG) molecules at the sn-2 position. Consequently, great attention has been accorded to the synthesis of structured acylglycerols (sAG), which include EPA or DHA at the sn-2 position. The aim of this work was to synthesize sAG starting from deodorized refined commercial salmon oil. For this, immobilized lipase B from Candida antarctica (nonspecific) was used as a catalyst for the intra-interesterification process under CO2 supercritical conditions (CO2SC). According to the CO2SC reaction time, three different fractions including sAG compounds were obtained. The location of EPA and DHA at the sn-2 position in the resulting glycerol backbone was identified by mass spectrometry (MALDI-TOF) analysis. In all fractions obtained, a marked decrease in the starting TG content was observed, while an increase in the DHA content at the sn-2 position was detected. The fraction obtained after the longest reaction time period (2 h) led to the highest yield of sn-2 position DHA in the resulting sAG molecule.


Asunto(s)
Ácidos Docosahexaenoicos/química , Ácido Eicosapentaenoico/química , Aceites de Pescado/química , Glicéridos/síntesis química , Triglicéridos/química , Animales , Basidiomycota , Catálisis , Técnicas de Química Analítica , Chile , Cromatografía en Capa Delgada , Esterificación , Ésteres/química , Ácidos Grasos/química , Humanos , Hidrólisis , Lipasa/química , Lípidos/química , Espectrometría de Masas , Probabilidad , Reproducibilidad de los Resultados , Alimentos Marinos/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
14.
Saudi Pharm J ; 29(9): 1061-1069, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34588851

RESUMEN

The medicinal uses of Calotropis procera are diverse, yet some of them are based on effects that still lack scientific support. Control of diabetes is one of them. Recently, latex proteins from C. procera latex (LP) have been shown to promote in vivo glycemic control by the inhibition of hepatic glucose production via AMP-activated protein kinase (AMPK). Glycemic control has been attributed to an isolated fraction of LP (CpPII), which is composed of cysteine peptidases (95%) and osmotin (5%) isoforms. Those proteins are extensively characterized in terms of chemistry, biochemistry and structural aspects. Furthermore, we evaluated some aspects of the mitochondrial function and cellular mechanisms involved in CpPII activity. The effect of CpPII on glycemic control was evaluated in fasting mice by glycemic curve and glucose and pyruvate tolerance tests. HepG2 cells was treated with CpPII, and cell viability, oxygen consumption, PPAR activity, production of lactate and reactive oxygen species, mitochondrial density and protein and gene expression were analyzed. CpPII reduced fasting glycemia, improved glucose tolerance and inhibited hepatic glucose production in control animals. Additionally, CpPII increased the consumption of ATP-linked oxygen and mitochondrial uncoupling, reduced lactate concentration, increased protein expression of mitochondrial complexes I, III and V, and activity of peroxisome-proliferator-responsive elements (PPRE), reduced the presence of reactive oxygen species (ROS) and increased mitochondrial density in HepG2 cells by activation of AMPK/PPAR. Our findings strongly support the medicinal use of the plant and suggest that CpPII is a potential therapy for prevention and/or treatment of type-2 diabetes. A common epitope sequence shared among the proteases and osmotin is possibly the responsible for the beneficial effects of CpPII.

15.
Am J Physiol Cell Physiol ; 319(3): C541-C551, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32697599

RESUMEN

Lin28a/miRNA let-7b-5p pathway has emerged as a key regulators of energy homeostasis in the skeletal muscle. However, the mechanism through which this pathway is regulated in the skeletal muscle has remained unclear. We have found that 8 wk of aerobic training (Tr) markedly decreased let-7b-5p expression in murine skeletal muscle, whereas high-fat diet (Hfd) increased its expression. Conversely, Lin28a expression, a well-known inhibitor of let-7b-5p, was induced by Tr and decreased by Hfd. Similarly, in human muscle biopsies, Tr increased LIN28 expression and decreased let-7b-5p expression. Bioinformatics analysis of LIN28a DNA sequence revealed that its enrichment in peroxisome proliferator-activated receptor delta (PPARδ) binding sites, which is a well-known metabolic regulator of exercise. Treatment of primary mouse skeletal muscle cells or C2C12 cells with PPARδ activators GW501516 and AICAR increased Lin28a expression. Lin28a and let-7b-5p expression was also regulated by PPARδ coregulators. While PPARγ coactivator-1α (PGC1α) increased Lin28a expression, corepressor NCoR1 decreased its expression. Furthermore, PGC1α markedly reduced the let-7b-5p expression. PGC1α-mediated induction of Lin28a expression was blocked by the PPARδ inhibitor GSK0660. In agreement, Lin28a expression was downregulated in PPARδ knocked-down cells leading to increased let-7b-5p expression. Finally, we show that modulation of the Lin28a-let-7b-5p pathway in muscle cells leads to changes in mitochondrial metabolism in PGC1α dependent fashion. In summary, we demonstrate that Lin28a-let-7b-5p is a direct target of PPARδ in the skeletal muscle, where it impacts mitochondrial respiration.


Asunto(s)
Mitocondrias/metabolismo , Músculo Esquelético/metabolismo , PPAR delta/metabolismo , Proteínas de Unión al ARN/genética , Animales , Línea Celular , Regulación hacia Abajo , Ratones , Fibras Musculares Esqueléticas/metabolismo , PPAR delta/genética
16.
J Biol Chem ; 294(46): 17249-17261, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31562243

RESUMEN

The anaphase-promoting complex/cyclosome (APC/C) is a large, multisubunit ubiquitin ligase involved in regulation of cell division. APC/C substrate specificity arises from binding of short degron motifs in its substrates to transient activator subunits, Cdc20 and Cdh1. The destruction box (D-box) is the most common APC/C degron and plays a crucial role in substrate degradation by linking the activator to the Doc1/Apc10 subunit of core APC/C to stabilize the active holoenzyme and promote processive ubiquitylation. Degrons are also employed as pseudosubstrate motifs by APC/C inhibitors, and pseudosubstrates must bind their cognate activators tightly to outcompete substrate binding while blocking their own ubiquitylation. Here we examined how APC/C activity is suppressed by the small pseudosubstrate inhibitor Acm1 from budding yeast (Saccharomyces cerevisiae). Mutation of a conserved D-box converted Acm1 into an efficient ABBA (cyclin A, BubR1, Bub1, Acm1) motif-dependent APC/CCdh1 substrate in vivo, suggesting that this D-box somehow inhibits APC/C. We then identified a short conserved sequence at the C terminus of the Acm1 D-box that was necessary and sufficient for APC/C inhibition. In several APC/C substrates, the corresponding D-box region proved to be important for their degradation despite poor sequence conservation, redefining the D-box as a 12-amino acid motif. Biochemical analysis suggested that the Acm1 D-box extension inhibits reaction processivity by perturbing the normal interaction with Doc1/Apc10. Our results reveal a simple, elegant mode of pseudosubstrate inhibition that combines high-affinity activator binding with specific disruption of Doc1/Apc10 function in processive ubiquitylation.


Asunto(s)
Subunidad Apc10 del Ciclosoma-Complejo Promotor de la Anafase/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Secuencias de Aminoácidos , Ciclo Celular , Proteínas de Ciclo Celular/química , Mapas de Interacción de Proteínas , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/citología , Proteínas de Saccharomyces cerevisiae/química , Especificidad por Sustrato , Ubiquitinación
17.
Eur Biophys J ; 49(6): 473-484, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32813035

RESUMEN

The aim of the present work was the biophysical characterization of the Amynthas gracilis hemoglobin (HbAg). The oxy-HbAg optical absorption data, with Soret and Q bands centered at 415, 540 and 575 nm, were stable and unchanged at pH 7.0. An increase in pH promotes decrease in the intensity in the optical absorption bands, suggesting an oligomeric dissociation and partial oxidation. Identical stability at pH 7.0 was observed in DLS results that presented a hydrodynamic diameter of 28 nm, characteristic of the whole oligomer. DLS shows that HbAg undergoes oligomeric dissociation and an aggregation/denaturation process that corroborates spectroscopic data. Our results showed that the monomer d presents four isoforms with molecular mass (MM) ranging from 16,244 to 16,855 Da; the trimer subunit presents two isoforms, (abc)1 and (abc)2, with MM of 51,415 ± 20 Da and 51,610 ± 14 Da, respectively, and a less intense species, at 67,793 Da, assigned to the tetramer abcd. Monomeric chains a, obtained from reduction of the disulfide-bonded trimer abc, present four isoforms with MM 17,015 Da, 17,061 Da, 17,138 Da and 17,259 Da. DLS and LSI revealed an isoeletric point (pI) of oxy-HbAg of 6.0 ± 0.3 and 5.5, respectively. Data analysis by IEF-SDS-PAGE revealed that the pI of oxy-HbAg is 6.11, correlating with DLS and LSI data. These studies indicate that oxy-HbAg is very stable, at pH 7.0, and has differing properties from orthologous giant hemoglobins.


Asunto(s)
Espacio Extracelular/metabolismo , Hemoglobinas/química , Hemoglobinas/metabolismo , Oligoquetos/citología , Animales , Concentración de Iones de Hidrógeno , Peso Molecular
18.
BMC Vet Res ; 16(1): 65, 2020 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-32085758

RESUMEN

BACKGROUND: The presence of Anisakis larvae in fish represents a major public health concern. Effective risk management procedures should be applied to prevent heavily infected products from reaching the market. The aim of the study is to provide preliminary data on parasite exposure and risk classification in frozen fish products by applying a risk categorization scheme (site, abundance, density and epidemiology - SADE) and Fish Parasite Rating (FPR) method. Fish and cephalopods samples (N = 771) from 5 different FAO Atlantic areas were examined and categorized after an accurate visual inspection and a chloro-peptic digestion. RESULTS: In 25 out of 33 fish species parasite larvae were found. 10897 anisakids larvae were collected and identified to genus level. Molva dypterygia, Conger conger, Zeus faber and Aphanopus carbo were shown to be the most highly infected species. SADE and FPR scores were 1 and poor, respectively, for the referred species, because of the disseminated Anisakis infection and commercial rejection. CONCLUSION: SADE/FPR method showed high specificity and accuracy. The information provided in this work could be used in early warning systems for the detection of parasites in fishery products and might help fishing industries in establishing management strategies for infected stocks in terms of cost saving decisions.


Asunto(s)
Anisakiasis/epidemiología , Enfermedades de los Peces/parasitología , Productos Pesqueros/parasitología , Animales , Anisakis/clasificación , Anisakis/genética , Anisakis/aislamiento & purificación , Océano Atlántico , Cefalópodos/parasitología , Peces , Parasitología de Alimentos/estadística & datos numéricos , Larva , Reacción en Cadena de la Polimerasa/métodos
19.
Am J Emerg Med ; 38(3): 554-561, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31171439

RESUMEN

BACKGROUND: Besides clinical signs and imaging, in recent years, biomarkers have proven to be a viable diagnostic resource for acute appendicitis (AA). OBJECTIVE: The objective of this study was to develop a clinical score including clinical signs and a combination of biomarkers to identify children with abdominal pain at low risk of AA. DESIGN/METHODS: We prospectively included children 2 to 14 years of age with abdominal pain suggestive of AA who presented to the emergency department between July 2016 and September 2017. A new score, the Pediatric Appendicitis Laboratory Score (PALabS) including clinical signs, leucocyte (WBC) and neutrophil (ANC) counts and plasma C-reactive protein (CRP) and calprotectin (CP) levels was developed and validated through secondary analyses of two distinct cohorts The validation sample included visits to a single pediatric emergency department from 2012 to 2013 and 2016 to 2017. RESULTS: The derivation sample included 278 children, 35.9% of whom had AA and the validation sample included 255 children, 49% of whom had AA. Using logistic regression, we created a 6-part score that consisted of nausea (3 points), history of focal right lower quadrant pain (4 points), ANC of ≥7500/µL (7 points), WBC of ≥10,000/µL (4 points), CRP ≥ 10.0 mg/L (2 points) and CP ≥ 0.50 ≥ ng/mL (3 points). This score exhibited a high discriminatory power (area under the curve: 0.88; 95% confidence interval: 0.84 to 0.92) and outperformed the PAS and Kharbanda scores (area under the curve: 0.76; 95% confidence interval: 0.71 to 0.82 and 0.82; 95% confidence interval: 0.77 to 0.87, respectively). A PALabS ≤6 had a sensitivity of 99.2% (95% confidence interval [CI]: 95.6-99.9), negative predictive value of 97.6% (95% CI: 87.7-99.6), and negative likelihood ratio of 0.03 (95% CI: 0.00-0.18) in the validation set. CONCLUSION: In our validation cohort of patients with acute abdominal pain, the new score can accurately predict which children are at low risk of appendicitis and could be safely managed with close observation.


Asunto(s)
Dolor Abdominal/etiología , Apendicitis/diagnóstico , Medición de Riesgo/métodos , Apendicitis/sangre , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Niño , Femenino , Humanos , Recuento de Leucocitos , Complejo de Antígeno L1 de Leucocito/sangre , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos
20.
Molecules ; 25(14)2020 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32674424

RESUMEN

The use of packaging films containing natural preservative compounds attracts great attention for the quality improvement of seafood. Microalga spirulina (Spirulina platensis) represents a potential source of high added-value and preservative biocompounds. The goal of this study was to enhance the quality of refrigerated Atlantic mackerel (Scomber scombrus) by including a protein concentrate (PC) of spirulina in a gelatine-based film. Quality changes in fish muscle were monitored by microbial and chemical analyses throughout an 11-day refrigerated storage (4 °C). As a result of the presence of spirulina PC in the film, an antimicrobial effect (p < 0.05) was concluded as determined by comparative evolution of aerobes and psychrotrophs, while no effect (p > 0.05) was concluded for Enterobacteriaceae, proteolytics and lipolytics counts. Furthermore, a lower (p < 0.05) formation of trimethylamine and free fatty acids was detected. Lipid oxidation, measured by fluorescent compounds formation, also exhibited lower average values in fish corresponding to the batch containing spirulina concentrate. The preservative effects observed can be explained on the basis of the presence of antimicrobial and antioxidant compounds in the microalga concentrate. It is proposed that the current packaging system may constitute a novel and promising strategy to enhance the quality of commercial refrigerated fatty fish.


Asunto(s)
Proteínas Bacterianas/química , Materiales Biocompatibles/química , Embalaje de Alimentos , Alimentos Marinos , Spirulina/química , Animales , Fenómenos Químicos , Peces , Microbiología de Alimentos , Concentración de Iones de Hidrógeno
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