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1.
Ecotoxicol Environ Saf ; 275: 116254, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38547729

RESUMEN

Heavy metal exposure leads to multiple system dysfunctions. The mechanisms are likely multifactorial and involve inflammation and oxidative stress. The aim of this study was to evaluate markers and risk factors for atherosclerosis in the LDL receptor knockout mouse model chronically exposed to inorganic mercury (Hg) in the drinking water. Results revealed that Hg exposed mice present increased plasma levels of cholesterol, without alterations in glucose. As a major source and target of oxidants, we evaluated mitochondrial function. We found that liver mitochondria from Hg treated mice show worse respiratory control, lower oxidative phosphorylation efficiency and increased H2O2 release. In addition, Hg induced mitochondrial membrane permeability transition. Erythrocytes from Hg treated mice showed a 50% reduction in their ability to take up oxygen, lower levels of reduced glutathione (GSH) and of antioxidant enzymes (SOD, catalase and GPx). The Hg treatment disturbed immune system cells counting and function. While lymphocytes were reduced, monocytes, eosinophils and neutrophils were increased. Peritoneal macrophages from Hg treated mice showed increased phagocytic activity. Hg exposed mice tissues present metal impregnation and parenchymal architecture alterations. In agreement, increased systemic markers of liver and kidney dysfunction were observed. Plasma, liver and kidney oxidative damage indicators (MDA and carbonyl) were increased while GSH and thiol groups were diminished by Hg exposure. Importantly, atherosclerotic lesion size in the aorta root of Hg exposed mice were larger than in controls. In conclusion, in vivo chronic exposure to Hg worsens the hypercholesterolemia, impairs mitochondrial bioenergetics and redox function, alters immune cells profile and function, causes several tissues oxidative damage and accelerates atherosclerosis development.


Asunto(s)
Aterosclerosis , Hipercolesterolemia , Mercurio , Animales , Ratones , Aterosclerosis/inducido químicamente , Peróxido de Hidrógeno , Enfermedades Renales , Mercurio/toxicidad , Ratones Noqueados , Estrés Oxidativo/fisiología , Receptores de LDL/genética
2.
Am J Physiol Heart Circ Physiol ; 325(3): H592-H600, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37539470

RESUMEN

Endothelial dysfunction is an early manifestation of atherosclerosis. The cholesteryl ester transfer protein (CETP) has been considered proatherogenic by reducing plasma HDL levels. However, CETP may exhibit cell- or tissue-specific effects. We have previously reported that male mice expressing the human CETP gene show impaired endothelium-mediated vascular relaxation associated with oxidative stress. Although sexual dimorphisms on the metabolic role of CETP have been proposed, possible sex differences in the vascular effects of CETP were not previously studied. Thus, here we investigated the endothelial function of female CETP transgenic mice as compared with nontransgenic controls (NTg). Aortas from CETP females presented preserved endothelium-dependent relaxation to acetylcholine and an endothelium-dependent reduction of phenylephrine-induced contraction. eNOS phosphorylation (Ser1177) and calcium-induced NO levels were enhanced, whereas reactive oxygen species (ROS) production and NOX2 and SOD2 expression were reduced in the CETP female aortas. Furthermore, CETP females exhibited increased aortic relaxation to 17ß-estradiol (E2) and upregulation of heat shock protein 90 (HSP90) and caveolin-1, proteins that stabilize estrogen receptor (ER) in the caveolae. Indeed, CETP females showed an increased E2-induced relaxation in a manner sensitive to estrogen receptor-α (ERα) and HSP90 inhibitors methylpiperidinopyrazole (MPP) and geldanamycin, respectively. MPP also impaired the relaxation response to acetylcholine in CETP but not in NTg females. Altogether, the study indicates that CETP expression ameliorates the anticontractile endothelial effect and relaxation to E2 in females. This was associated with less ROS production, and increased eNOS-NO and E2-ERα pathways. These results highlight the need for considering the sex-specific effects of CETP on cardiovascular risk.NEW & NOTEWORTHY Here we demonstrated that CETP expression has a sex-specific impact on the endothelium function. Contrary to what was described for males, CETP-expressing females present preserved endothelium-dependent relaxation to acetylcholine and improved relaxation response to 17ß-estradiol. This was associated with less ROS production, increased eNOS-derived NO, and increased expression of proteins that stabilize estrogen receptor-α (ERα), thus increasing E2-ERα signaling sensitivity. These results highlight the need for considering the sex-specific effects of CETP on cardiovascular risk.


Asunto(s)
Proteínas de Transferencia de Ésteres de Colesterol , Receptor alfa de Estrógeno , Óxido Nítrico Sintasa de Tipo III , Animales , Femenino , Ratones , Acetilcolina/farmacología , Proteínas de Transferencia de Ésteres de Colesterol/genética , Endotelio/metabolismo , Endotelio Vascular/metabolismo , Estradiol/farmacología , Receptor alfa de Estrógeno/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Vasodilatación
3.
Cell Physiol Biochem ; 57(5): 331-344, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37724045

RESUMEN

BACKGROUND/AIMS: Recombinant adeno-associated viruses (rAAV) are an important tool for lung targeted gene therapy. Substitution of tyrosine with phenylalanine residues (Y-F) in the capsid have been shown to protect the AAV vector from ubiquitin/proteasome degradation, increasing transduction efficiency. We tested the mutant Y733F-AAV8 vector for mucus diffusion, as well as the safety and efficacy of pigment epithelium-derived factor (PEDF) gene transfer to the lung. METHODS: For this purpose, Y733F-AAV8-PEDF (1010 viral genome) was administered intratracheally to C57BL/6 mice. Lung mechanics, morphometry, and inflammation were evaluated 7, 14, 21, and 28 days after injection. RESULTS: The tyrosine-mutant AAV8 vector was efficient at penetrating mucus in ex vivo assays and at transferring the gene to lung cells after in vivo instillation. Increased levels of transgene mRNA were observed 28 days after vector administration. Overexpression of PEDF did not affect in vivo lung parameters. CONCLUSION: These findings provide a basis for further development of Y733F-AAV8-based gene therapies for safe and effective delivery of PEDF, which has anti-angiogenic, anti-inflammatory and anti-fibrotic activities and might be a promising therapy for lung inflammatory disorders.


Asunto(s)
Proteínas del Ojo , Técnicas de Transferencia de Gen , Serpinas , Animales , Ratones , Proteínas del Ojo/genética , Ratones Endogámicos C57BL , Factores de Crecimiento Nervioso/genética , Serpinas/genética
4.
Environ Res ; 224: 115504, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36796604

RESUMEN

Marine heatwaves (MHWs) are extreme weather events featuring abnormally high seawater temperature, and expected to increase in frequency, duration and severity over this century. The impacts of these phenomena on physiological performance of coral reef species require understanding. This study aimed to evaluate the effects of a simulated MHW (category IV; ΔT = +2 °C, 11 days) (after exposure and 10-day recovery period) on fatty acid (FA) composition (as a biochemical indicator) and energy budget (i.e., growth, G, excretion (faecal, F and nitrogenous losses, U), respiration, R and food consumption, C) of a juvenile tropical surgeonfish species (Zebrasoma scopas). Significant and different changes were found under MHW scenario for some of the most abundant FA and respective groups (i.e., an increase in the contents of 14:0, 18:1n-9, ΣMonounsaturated (ΣMUFA) and 18:2n-6; and a decrease in the levels of 16:0, ΣSaturated (ΣSFA), 18:1n-7, 22:5n-3 and ΣPolyunsaturated (ΣPUFA)). The contents of 16:0 and ΣSFA were also significantly lower after MHW exposure compared to control (CTRL). Additionally, lower feed efficiency (FE), relative growth rate (RGR) and specific growth rate in terms of wet weight (SGRw), as well as higher energy loss for respiration were observed under MHW exposure conditions in comparison with CTRL and MHW recovery period. The energy proportion channelled for faeces dominated the mode of energy allocation, followed by growth in both treatments (after exposure). After MHW recovery, this trend was reversed, and a higher percentage was spent for growth and a lower fraction for faeces than in the MHW exposure period. Overall, FA composition, growth rates and energy loss for respiration of Z. Scopas were the physiological parameters most influenced (mainly in a negative way) by an 11-day MHW event. The observed effects in this tropical species can be exacerbated with increasing intensity and frequency of these extreme events.


Asunto(s)
Ácidos Grasos , Perciformes , Animales , Ecosistema , Peces , Agua de Mar , Temperatura
5.
Int J Mol Sci ; 24(23)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38069233

RESUMEN

Atmospheric particulate matter (PM) with diameters below 10 µm (PM10) may enter the lungs through inhalation and are linked to various negative health consequences. Emergent evidence emphasizes the significance of cell metabolism as a sensitive target of PM exposure. However, the current understanding of the relationship between PM composition, conventional toxicity measures, and the rewiring of intracellular metabolic processes remains limited. In this work, PM10 sampled at a residential area (urban background, UB) and a traffic-impacted location (roadside, RS) of a Portuguese city was comprehensively characterized in terms of polycyclic aromatic hydrocarbons and plasticizers. Epithelial lung cells (A549) were then exposed for 72 h to PM10 organic extracts and different biological outcomes were assessed. UB and RS PM10 extracts dose-dependently decreased cell viability, induced reactive oxygen species (ROS), decreased mitochondrial membrane potential, caused cell cycle arrest at the G0/G1 phase, and modulated the intracellular metabolic profile. Interestingly, the RS sample, richer in particularly toxic PAHs and plasticizers, had a greater metabolic impact than the UB extract. Changes comprised significant increases in glutathione, reflecting activation of antioxidant defences to counterbalance ROS production, together with increases in lactate, NAD+, and ATP, which suggest stimulation of glycolytic energy production, possibly to compensate for reduced mitochondrial activity. Furthermore, a number of other metabolic variations hinted at changes in membrane turnover and TCA cycle dynamics, which represent novel clues on potential PM10 biological effects.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Material Particulado/toxicidad , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Especies Reactivas de Oxígeno/farmacología , Plastificantes/farmacología , Pulmón/metabolismo , Hidrocarburos Policíclicos Aromáticos/farmacología , Monitoreo del Ambiente
6.
Molecules ; 28(12)2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37375331

RESUMEN

Melanoma incidence, a type of skin cancer, has been increasing worldwide. There is a strong need to develop new therapeutic strategies to improve melanoma treatment. Morin is a bioflavonoid with the potential for use in the treatment of cancer, including melanoma. However, therapeutic applications of morin are restrained owing to its low aqueous solubility and limited bioavailability. This work investigates morin hydrate (MH) encapsulation in mesoporous silica nanoparticles (MSNs) to enhance morin bioavailability and consequently increase the antitumor effects in melanoma cells. Spheroidal MSNs with a mean size of 56.3 ± 6.5 nm and a specific surface area of 816 m2/g were synthesized. MH was successfully loaded (MH-MSN) using the evaporation method, with a loading capacity of 28.3% and loading efficiency of 99.1%. In vitro release studies showed that morin release from MH-MSNs was enhanced at pH 5.2, indicating increased flavonoid solubility. The in vitro cytotoxicity of MH and MH-MSNs on human A375, MNT-1 and SK-MEL-28 melanoma cell lines was investigated. Exposure to MSNs did not affect the cell viability of any of the cell lines tested, suggesting that the nanoparticles are biocompatible. The effect of MH and MH-MSNs on reducing cell viability was time- and concentration-dependent in all melanoma cell lines. The A375 and SK-MEL-28 cell lines were slightly more sensitive than MNT-1 cells in both the MH and MH-MSN treatments. Our findings suggest that MH-MSNs are a promising delivery system for the treatment of melanoma.


Asunto(s)
Melanoma , Nanopartículas , Humanos , Dióxido de Silicio , Sistemas de Liberación de Medicamentos/métodos , Portadores de Fármacos , Melanoma/tratamiento farmacológico , Flavonoides/farmacología , Porosidad
7.
Biochem Biophys Res Commun ; 606: 61-67, 2022 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-35339753

RESUMEN

Macrophages play a role in host defense, tissue remodeling and inflammation. Different inflammatory stimuli drive macrophage phenotypes and responses. In this study we investigated the relationship between macrophages immune phenotype and mitochondrial bioenergetics, cell redox state and endoplasmic reticulum (ER)-mitochondria interaction. Bacterial lipopolysaccharide (LPS) and interferon-γ (IFNγ) pro-inflammatory stimuli decreased oxidative metabolism (basal, phosphorylating and maximal conditions) and increased baseline glycolysis (117%) and glycolytic capacity (43%) in THP-1 macrophages. In contrast, interleukin-4 (IL4) and interleukin-13 (IL13) anti-inflammatory stimuli increased the oxygen consumption rates in baseline conditions (21%) and associated with ATP production (19%). LPS + IFNγ stimuli reduced superoxide anion levels by accelerating its conversion into hydrogen peroxide (H2O2) while IL4+IL13 decreased H2O2 release rates. The source of these oxidants was extra-mitochondrial and associated with increased NOX2 and SOD1 gene expression. LPS + IFNγ stimuli decreased ER-mitochondria contact sites as measured by IP3R1-VDAC1 interaction (34%) and markedly upregulated genes involved in mitochondrial fusion (9-10 fold, MFN1 and 2) and fission (∼7 fold, DRP1 and FIS1). Conversely, IL4+IL13 stimuli did not altered ER-mitochondria interactions nor MFN1 and 2 expression. Together, these results unveil ER-mitochondria interaction pattern as a novel feature of macrophage immunological, metabolic and redox profiles.


Asunto(s)
Interleucina-13 , Interleucina-4 , Retículo Endoplásmico/metabolismo , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/farmacología , Interferón gamma/metabolismo , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Mitocondrias/metabolismo
8.
Eye Contact Lens ; 48(8): 322-327, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35389370

RESUMEN

OBJECTIVE: To verify corneal alterations in patients with keratoconus who wear scleral contact lenses (ScCLs), focusing on corneal endothelial assessment. METHODS: Scleral contact lenses were fitted in 22 patients with keratoconus. During a 90-day follow-up, patients were assessed in three visits: at baseline, after 30 days, and after 90 days. Patients underwent visual acuity measurement, slitlamp biomicroscopy of the anterior segment, specular microscopy of the corneal endothelium, corneal pachymetry, measurement of the clearance between the cornea and the lens, and follow-up of ectasia. RESULTS: Variables related to endothelial morphology and pachymetry values did not change significantly over time. Central clearance measurements decreased in the 90-day period. No progression of corneal ectasia was observed, neither were infectious or inflammatory processes in the same period. CONCLUSION: Daily wear of ScCLs in patients with keratoconus was not associated with adverse effects on the cornea or endothelium over a period of 90 days nor was there evidence of disease progression. Central clearance values diminished over that period, but the significance of this observation remains unclear.


Asunto(s)
Lentes de Contacto , Queratocono , Lentes de Contacto/efectos adversos , Córnea , Topografía de la Córnea , Dilatación Patológica , Humanos , Queratocono/terapia , Esclerótica
9.
Int J Mol Sci ; 23(7)2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35408947

RESUMEN

Melanoma is a drug-resistant cancer, representing a serious challenge in cancer treatment. Dacarbazine (DTIC) is the standard drug in metastatic melanoma treatment, despite the poor results. Hyperthermia has been proven to potentiate chemotherapy. Hence, this work analyzed the combined action of hyperthermia and DTIC on A375 and MNT-1 cell lines. First, temperatures between 40 °C and 45 °C were tested. The effect of DTIC on cell viability was also investigated after exposures of 24, 48, and 72 h. Then, cells were exposed to 43 °C and to the respective DTIC IC10 or IC20 of each time exposure. Overall, hyperthermia reduced cell viability, however, 45 °C caused an excessive cell death (>90%). Combinational treatment revealed that hyperthermia potentiates DTIC's effect, but it is dependent on the concentration and temperature used. Also, it has different mechanisms from the treatments alone, delaying A375 cells at the G2/M phase and MNT-1 cells at the S and G2/M phases. Intracellular reactive oxygen species (ROS) levels increased after treatment with hyperthermia, but the combined treatment showed no additional differences. Also, hyperthermia highly increased the number of A375 early apoptotic cells. These results suggest that combining hyperthermia and DTIC should be more explored to improve melanoma treatment.


Asunto(s)
Hipertermia Inducida , Melanoma , Línea Celular Tumoral , Supervivencia Celular , Dacarbazina/farmacología , Dacarbazina/uso terapéutico , Humanos , Melanoma/tratamiento farmacológico , Melanoma/metabolismo , Especies Reactivas de Oxígeno/metabolismo
10.
J Environ Sci (China) ; 115: 215-226, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34969449

RESUMEN

Particulate matter emissions (PM10) from the combustion, in a residential stove, of two commercial brands of certified (ENplus A1) pellets, a non-certified brand and laboratory made pellets of acacia were tested for their ability to induce ecotoxic, cytotoxic, and mutagenic responses in unicellular organisms and a human cell line. Ecotoxicity was evaluated through the Vibrio fischeri bioluminescence inhibition assay. Moreover, cytotoxicity was assessed at two time points (24- and 48-hr) through two complementary techniques in order to evaluate the cellular metabolic activity and membrane integrity of human lung epithelial cells A549. The Ames test using two Salmonella typhimurium strains (TA100 and TA98) was employed to assess the mutagenic potential of the polycyclic aromatic hydrocarbon fraction extracted from the PM10 samples. Results obtained with the bioluminescent bacteria indicated that only particles from the combustion of acacia pellets were toxic. All samples induced impairment on the A549 cells metabolic activity, while no significant release of lactate dehydrogenase was recorded. PM10 emissions from acacia pellets were the most cytotoxic, while samples from both certified pellets evoked significant cytotoxicity at lower doses. Cytotoxicity time-dependency was only observed for PM10 from the combustion of acacia pellets and one of the brands of certified pellets. Mutagenic activity was not detected in both S. typhimurium strains. This study emphasises the role of the raw material for pellet manufacturing on the toxicological profile of PM emissions. Alternative raw materials should be deeply investigated before their use in pelletisation and combustion in residential appliances.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Humanos , Pruebas de Mutagenicidad , Mutágenos , Material Particulado/análisis , Material Particulado/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Emisiones de Vehículos , Madera/química
11.
Neurochem Res ; 46(5): 1092-1100, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33544325

RESUMEN

Chronic opioid use changes brain chemistry in areas related to reward processes, memory, decision-making, and addiction. Both neurons and astrocytes are affected, ultimately leading to dependence. Passiflora incarnata L. (Passifloraceae) is the basis of frequently used herbals to manage anxiety and insomnia, with proven central nervous system depressant effects. Anti-addiction properties of P. incarnata have been reported. The aim of this study was to investigate the effect of a commercial extract of Passiflora incarnata (Sintocalmy®, Aché Laboratory) in the naloxone-induced jumping mice model of morphine withdrawal. In addition, glial fibrillary acidic protein (GFAP) and S100 calcium-binding protein B (S100B) levels were assessed in the frontal cortex and hippocampus, and DNA damage was verified on blood cells. In order to improve solubilization a Sintocalmy methanol extract (SME) was used. SME is mainly composed by flavonoids isovitexin and vitexin. The effects of SME 50, 100 and 200 mg/kg (i.p.) were evaluated in the naloxone-induced withdrawal syndrome in mice. SME 50 and SME 100 mg/kg decreased naloxone-induced jumping in morphine-dependent mice without reducing locomotor activity. No alterations were found in GFAP levels, however SME 50 mg/kg prevented the S100B increase in the frontal cortex and DNA damage. This study shows anti-addiction effects for a commercial standardized extract of P. incarnata and suggests the relevance of proper clinical assessment.


Asunto(s)
Ansiolíticos/uso terapéutico , Morfina/efectos adversos , Extractos Vegetales/uso terapéutico , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Animales , Daño del ADN/efectos de los fármacos , Proteína Ácida Fibrilar de la Glía/metabolismo , Locomoción/efectos de los fármacos , Masculino , Ratones , Dependencia de Morfina/tratamiento farmacológico , Naloxona/uso terapéutico , Passiflora , Subunidad beta de la Proteína de Unión al Calcio S100/metabolismo
12.
Int J Mol Sci ; 23(1)2021 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-35008457

RESUMEN

Melanoma is the deadliest form of skin cancer, and its incidence has alarmingly increased in the last few decades, creating a need for novel treatment approaches. Thus, we evaluated the combinatorial effect of doxorubicin (DOX) and hyperthermia on A375 and MNT-1 human melanoma cell lines. Cells were treated with DOX for 24, 48, and 72 h and their viabilities were assessed. The effect of DOX IC10 and IC20 (combined at 43 °C for 30, 60, and 120 min) on cell viability was further analyzed. Interference on cell cycle dynamics, reactive oxygen species (ROS) production, and apoptosis upon treatment (with 30 min at 43 °C and DOX at the IC20 for 48 h) were analyzed by flow cytometry. Combined treatment significantly decreased cell viability, but not in all tested conditions, suggesting that the effect depends on the drug concentration and heat treatment duration. Combined treatment also mediated a G2/M phase arrest in both cell lines, as well as increasing ROS levels. Additionally, it induced early apoptosis in MNT-1 cells, while in A375 cells this effect was similar to the one caused by hyperthermia alone. These findings demonstrate that hyperthermia enhances DOX effect through cell cycle arrest, oxidative stress, and apoptotic cell death.


Asunto(s)
Doxorrubicina/farmacología , Melanoma/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Hipertermia Inducida/métodos , Puntos de Control de la Fase M del Ciclo Celular/efectos de los fármacos , Melanoma/metabolismo , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Cutáneas/metabolismo
13.
J Child Lang ; 48(4): 699-716, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-32958084

RESUMEN

Reading is one of the most important milestones a child achieves throughout development. Above the letter level, the syllable has been shown to play a relevant role at early stages of visual word recognition in adult skilled readers. However, studies aiming to examine when, during reading acquisition, the syllable emerges as a functional sublexical unit are scarce, and the studies conducted so far have led to inconsistent results. In this work, beginning and intermediate European-Portuguese (EP) developing readers performed a sandwich masked lexical decision task in which CV (e.g., RU.MOR[rumour]) and CVC (e.g., CIS.NE[swan]) first-syllable EP words were preceded either by syllable congruent (e.g., rum.ba-RU.MOR, cis.ra-CIS.NE), syllable incongruent (e.g., rum.ba-RU.MOR, ci.ser-CIS.NE), unrelated (e.g., va.cra-RU.MOR, zar.vo-CIS.NE) pseudowords primes, or identity (e.g., ru.mour-RU.MOUR, cis.ne-CIS.NE) primes. Results showed reliable syllable effects only for intermediate readers and for CV and CVC words alike. Findings are discussed attending to current models of visual word recognition.


Asunto(s)
Etnicidad , Lectura , Familia , Humanos , Reconocimiento Visual de Modelos , Portugal , Tiempo de Reacción
14.
Crit Care Med ; 48(4): e290-e298, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32205619

RESUMEN

OBJECTIVES: Survivors of sepsis are frequently left with significant cognitive and behavioral impairments. These complications derive from nonresolving inflammation that persists following hospital discharge. To date, no study has investigated the effects of mesenchymal stromal cell therapy on the blood-brain barrier, astrocyte activation, neuroinflammation, and cognitive and behavioral alterations in experimental sepsis. DESIGN: Prospective, randomized, controlled experimental study. SETTING: Government-affiliated research laboratory. SUBJECTS: Male Swiss Webster mice (n = 309). INTERVENTIONS: Sepsis was induced by cecal ligation and puncture; sham-operated animals were used as control. All animals received volume resuscitation (1 mL saline/mouse subcutaneously) and antibiotics (meropenem 10 mg/kg intraperitoneally at 6, 24, and 48 hours). Six hours after surgery, mice were treated with mesenchymal stromal cells IV (1 × 10 cells in 0.05 mL of saline/mouse) or saline (0.05 mL IV). MEASUREMENTS AND MAIN RESULTS: At day 1, clinical score and plasma levels of inflammatory mediators were increased in cecal ligation and puncture mice. Mesenchymal stromal cells did not alter clinical score or survival rate, but reduced levels of systemic interleukin-1ß, interleukin-6, and monocyte chemoattractant protein-1. At day 15, survivor mice completed a battery of cognitive and behavioral tasks. Cecal ligation and puncture mice exhibited spatial and aversive memory deficits and anxiety-like behavior. These effects may be related to increased blood-brain barrier permeability, with altered tight-junction messenger RNA expression, increased brain levels of inflammatory mediators, and astrogliosis (induced at day 3). Mesenchymal stromal cells mitigated these cognitive and behavioral alterations, as well as reduced blood-brain barrier dysfunction, astrocyte activation, and interleukin-1ß, interleukin-6, tumor necrosis factor-α, and interleukin-10 levels in vivo. In cultured primary astrocytes stimulated with lipopolysaccharide, conditioned media from mesenchymal stromal cells reduced astrogliosis, interleukin-1ß, and monocyte chemoattractant protein-1, suggesting a paracrine mechanism of action. CONCLUSIONS: In mice who survived experimental sepsis, mesenchymal stromal cell therapy protected blood-brain barrier integrity, reduced astrogliosis and neuroinflammation, as well as improved cognition and behavior.


Asunto(s)
Barrera Hematoencefálica , Trastornos del Conocimiento , Gliosis , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Sepsis , Animales , Masculino , Ratones , Conducta Animal , Barrera Hematoencefálica/metabolismo , Trastornos del Conocimiento/prevención & control , Modelos Animales de Enfermedad , Gliosis/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/metabolismo , Estudios Prospectivos , Sepsis/terapia
15.
Conscious Cogn ; 80: 102919, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32200204

RESUMEN

Three experiments explored the extent to which surface features explain discrimination between grammatical and non-grammatical strings in artificial grammar learning (AGL). Experiment 1 replicated Knowlton and Squire's (1996) paradigm using either letter strings as in the original study, or an analogous set of color strings to further explore if learning was affected by type of stimuli. Learning arose only with letter strings, but the results were mostly due to the discrimination of non-grammatical strings containing highly salient illegal features. Experiments 2 and 3 tested a new grammar devised to control for those features. Experiment 2 showed reduced grammar learning effects, and again only for letter materials. Experiment 3 explored the effect of additional practice with letter stimuli, and found increased learning only in the spaced practice condition, though additional practice also produced more explicit knowledge. These findings call for further research on the boundary conditions of learning in AGL paradigms.


Asunto(s)
Percepción de Color/fisiología , Aprendizaje/fisiología , Reconocimiento Visual de Modelos/fisiología , Psicolingüística , Adolescente , Adulto , Femenino , Humanos , Práctica Psicológica , Adulto Joven
16.
Biochem J ; 476(24): 3769-3789, 2019 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-31803904

RESUMEN

The atherosclerosis prone LDL receptor knockout mice (Ldlr-/-, C57BL/6J background) carry a deletion of the NADP(H)-transhydrogenase gene (Nnt) encoding the mitochondrial enzyme that catalyzes NADPH synthesis. Here we hypothesize that both increased NADPH consumption (due to increased steroidogenesis) and decreased NADPH generation (due to Nnt deficiency) in Ldlr-/- mice contribute to establish a macrophage oxidative stress and increase atherosclerosis development. Thus, we compared peritoneal macrophages and liver mitochondria from three C57BL/6J mice lines: Ldlr and Nnt double mutant, single Nnt mutant and wild-type. We found increased oxidants production in both mitochondria and macrophages according to a gradient: double mutant > single mutant > wild-type. We also observed a parallel up-regulation of mitochondrial biogenesis (PGC1a, TFAM and respiratory complexes levels) and inflammatory (iNOS, IL6 and IL1b) markers in single and double mutant macrophages. When exposed to modified LDL, the single and double mutant cells exhibited significant increases in lipid accumulation leading to foam cell formation, the hallmark of atherosclerosis. Nnt deficiency cells showed up-regulation of CD36 and down-regulation of ABCA1 transporters what may explain lipid accumulation in macrophages. Finally, Nnt wild-type bone marrow transplantation into LDLr-/- mice resulted in reduced diet-induced atherosclerosis. Therefore, Nnt plays a critical role in the maintenance of macrophage redox, inflammatory and cholesterol homeostasis, which is relevant for delaying the atherogenesis process.


Asunto(s)
Aterosclerosis/metabolismo , Macrófagos Peritoneales/metabolismo , NADP/metabolismo , Estrés Oxidativo , Transportador 1 de Casete de Unión a ATP/genética , Transportador 1 de Casete de Unión a ATP/metabolismo , Animales , Aterosclerosis/inducido químicamente , Aterosclerosis/genética , Biomarcadores , Antígenos CD36/metabolismo , Dieta Alta en Grasa , Regulación de la Expresión Génica , Genotipo , Glutatión/metabolismo , Inflamación , Masculino , Ratones , Ratones Noqueados , Mitocondrias/metabolismo , Mutación , NADP Transhidrogenasas , Receptores de LDL/genética , Superóxidos/metabolismo
17.
Adv Exp Med Biol ; 1276: 15-25, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32705591

RESUMEN

In this chapter, we present the major advances in CETP research since the detection, isolation, and characterization of its activity in the plasma of humans and several species. Since CETP is a major modulator of HDL plasma levels, the clinical importance of CETP activity was recognized very early. We describe the participation of CETP in reverse cholesterol transport, conflicting results in animal and human genetic studies, possible new functions of CETP, and the results of the main clinical trials on CETP inhibition. Despite major setbacks in clinical trials, the hypothesis that CETP inhibitors are anti-atherogenic in humans is still being tested.


Asunto(s)
Enfermedades Cardiovasculares , Proteínas de Transferencia de Ésteres de Colesterol , Metabolismo de los Lípidos , Animales , Aterosclerosis , Transporte Biológico , Humanos
18.
Int J Health Care Qual Assur ; ahead-of-print(ahead-of-print)2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-32255278

RESUMEN

PURPOSE: We explore the relationship between the balanced scorecard (BSC) and neo-bureaucracy by investigating whether the operationalization of the BSC incorporates "neo-bureaucratic" ideas and whether the BSC implemented in a Portuguese Local Health Unit (LHU) demonstrates a neo-bureaucratic approach. DESIGN/METHODOLOGY/APPROACH: We conduct semi-structured interviews with LHU staff and analyse documents to assess whether features of bureaucratic organization were evident in the use of a BSC by the LHU. FINDINGS: We found nine bureaucratic features evident in the LHU's BSC. These were systematization, rationality, authority, jurisdiction, professional qualification, knowledge, discipline, transparency and accountability. The BSC used at the LHU demonstrated a neo-bureaucratic approach. ORIGINALITY/VALUE: Our study helps to demystify bureaucracy and overcome prevailing prejudices regarding some of its principles. Health care managers should recognize and endorse neo-bureaucratic principles in developing a BSC. They should recognize the BSC as involving a neo-bureaucratic approach. The BSC is a valuable management tool that hospital managers should find useful in fostering flexibility, collaboration, innovation and adaptation - all of which should help lead to improved healthcare outcomes.


Asunto(s)
Administración de los Servicios de Salud , Modelos Organizacionales , Objetivos Organizacionales , Garantía de la Calidad de Atención de Salud/organización & administración , Humanos , Estudios de Casos Organizacionales , Portugal , Indicadores de Calidad de la Atención de Salud/organización & administración
19.
J Cell Physiol ; 234(7): 11047-11059, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30536661

RESUMEN

New onset of diabetes is associated with the use of statins. We have recently demonstrated that pravastatin-treated hypercholesterolemic LDL receptor knockout (LDLr-/- ) mice exhibit reductions in insulin secretion and increased islet cell death and oxidative stress. Here, we hypothesized that these diabetogenic effects of pravastatin could be counteracted by treatment with the antioxidant coenzyme Q 10 (CoQ 10 ), an intermediate generated in the cholesterol synthesis pathway. LDLr -/- mice were treated with pravastatin and/or CoQ 10 for 2 months. Pravastatin treatment resulted in a 75% decrease of liver CoQ 10 content. Dietary CoQ 10 supplementation of pravastatin-treated mice reversed fasting hyperglycemia, improved glucose tolerance (20%) and insulin sensitivity (>2-fold), and fully restored islet glucose-stimulated insulin secretion impaired by pravastatin (40%). Pravastatin had no effect on insulin secretion of wild-type mice. In vitro, insulin-secreting INS1E cells cotreated with CoQ 10 were protected from cell death and oxidative stress induced by pravastatin. Simvastatin and atorvastatin were more potent in inducing dose-dependent INS1E cell death (10-15-fold), which were also attenuated by CoQ 10 cotreatment. Together, these results demonstrate that statins impair ß-cell redox balance, function and viability. However, CoQ 10 supplementation can protect the statins detrimental effects on the endocrine pancreas.


Asunto(s)
Hipercolesterolemia/tratamiento farmacológico , Células Secretoras de Insulina/efectos de los fármacos , Pravastatina/efectos adversos , Receptores de LDL/metabolismo , Ubiquinona/análogos & derivados , Animales , Línea Celular , Supervivencia Celular , Diabetes Mellitus/inducido químicamente , Suplementos Dietéticos , Femenino , Prueba de Tolerancia a la Glucosa , Peróxido de Hidrógeno , Insulina , Hígado/metabolismo , Ratones , Ratones Noqueados , Pravastatina/uso terapéutico , Receptores de LDL/genética , Ubiquinona/farmacología
20.
J Transl Med ; 17(1): 285, 2019 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-31455371

RESUMEN

BACKGROUND: HMG-CoA reductase inhibitors (statins) are cholesterol-lowering drugs widely used to treat hypercholesterolemia and prevent cardiovascular disease. Statins are generally well tolerated, but adverse reactions may occur, particularly myopathy and new onset of diabetes. The exact mechanism of statin-induced myopathy and diabetes has not been fully elucidated. We have previously shown that treatment of hypercholesterolemic (LDLr-/-) mice with pravastatin for 2 months decreased pancreatic islet insulin secretion and increased oxidative stress and cell death, but no glucose intolerance was observed. The purpose of the current work was to study long-term pravastatin effects on glucose homeostasis, insulin sensitivity, muscle protein turnover and cell viability. METHODS: LDLr-/- mice were treated with pravastatin for 3, 6 and 10 months. Glucose tolerance, insulin resistance and glucose-stimulated insulin secretion were evaluated. The rates of protein synthesis and degradation were determined in gastrocnemius muscle after 10 months of treatment. Insulin signalling, oxidative stress and cell death were analysed in vitro using C2C12 myotubes. RESULTS: After 6 and 10 months of treatment, these mice became glucose intolerant, and after 10 months, they exhibited marked insulin resistance. Reduced islet glucose-stimulated insulin secretion was observed after the 3rd month of treatment. Mice treated for 10 months showed significantly decreased body weight and increased muscle protein degradation. In addition, muscle chymotrypsin-like proteasomal activity and lysosomal cathepsin were markedly elevated. C2C12 myotubes exposed to increasing concentrations of pravastatin presented dose-dependent impairment of insulin-induced Akt phosphorylation, increased apoptotic markers (Bax protein and cleaved caspase-3) and augmented superoxide anion production. CONCLUSIONS: In addition to reduced insulin secretion, long-term pravastatin treatment induces insulin resistance and muscle wasting. These results suggest that the diabetogenic effect of statins is linked to the appearance of myotoxicity induced by oxidative stress, impaired insulin signalling, proteolysis and apoptosis.


Asunto(s)
Diabetes Mellitus Experimental/complicaciones , Hipercolesterolemia/complicaciones , Resistencia a la Insulina , Miotoxicidad/complicaciones , Pravastatina/efectos adversos , Animales , Apoptosis , Glucemia/metabolismo , Peso Corporal , Línea Celular , Diabetes Mellitus Experimental/sangre , Ayuno/sangre , Femenino , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/complicaciones , Homeostasis , Hipercolesterolemia/sangre , Insulina/sangre , Secreción de Insulina , Ratones Endogámicos C57BL , Modelos Biológicos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patología , Proteínas Musculares/metabolismo , Miotoxicidad/sangre , Estrés Oxidativo , Fosforilación , Proteolisis , Receptores de LDL/deficiencia , Receptores de LDL/metabolismo , Transducción de Señal , Superóxidos/metabolismo
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