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1.
Int J Mol Sci ; 24(2)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36674779

RESUMEN

Cell death program of red blood cells (RBCs), called eryptosis, is characterized by activation of caspases and scrambling of membrane phospholipids with externalization of phosphatidylserine (PS). Excessive eryptosis confers a procoagulant phenotype and is implicated in impairment of microcirculation and increased prothrombotic risk. It has recently been reported that cigarette smokers have high levels of circulating eryptotic erythrocytes, and a possible contribution of eryptosis to the vaso-occlusive complications associated to cigarette smoke has been postulated. In this study, we demonstrate how a mixture of plant sterols (MPtS) consisting of ß-sitosterol, campesterol and stigmasterol, at serum concentration reached after ingestion of a drink enriched with plant sterols, inhibits eryptosis induced by cigarette smoke extract (CSE). Isolated RBCs were exposed for 4 h to CSE (10-20% v/v). When RBCs were co-treated with CSE in the presence of 22 µM MPtS, a significant reduction of the measured hallmarks of apoptotic death like assembly of the death-inducing signaling complex (DISC), PS outsourced, ceramide production, cleaved forms of caspase 8/caspase 3, and phosphorylated p38 MAPK, was evident. The new beneficial properties of plant sterols on CSE-induced eryptosis presented in this work open new perspectives to prevent the negative physio-pathological events caused by the eryptotic red blood cells circulating in smokers.


Asunto(s)
Fumar Cigarrillos , Eriptosis , Fitosteroles , Fumar Cigarrillos/efectos adversos , Eritrocitos/metabolismo , Fitosteroles/farmacología , Fitosteroles/metabolismo , Muerte Celular , Calcio/metabolismo , Fosfatidilserinas/metabolismo
2.
Int J Mol Sci ; 24(4)2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36834882

RESUMEN

Obesity is linked to neurodegeneration, which is mainly caused by inflammation and oxidative stress. We analyzed whether the long-term intake of honey and/or D-limonene, which are known for their antioxidant and anti-inflammatory actions, when ingested separately or in combination, can counteract the neurodegeneration occurring in high fat diet (HFD)-induced obesity. After 10 weeks of HFD, mice were divided into: HFD-, HFD + honey (HFD-H)-, HFD + D-limonene (HFD-L)-, HFD + honey + D-limonene (HFD-H + L)-fed groups, for another 10 weeks. Another group was fed a standard diet (STD). We analyzed the brain neurodegeneration, inflammation, oxidative stress, and gene expression of Alzheimer's disease (AD) markers. The HFD animals showed higher neuronal apoptosis, upregulation of pro-apoptotic genes Fas-L, Bim P27 and downregulation of anti-apoptotic factors BDNF and BCL2; increased gene expression of the pro-inflammatory IL-1ß, IL-6 and TNF-α and elevated oxidative stress markers COX-2, iNOS, ROS and nitrite. The honey and D-limonene intake counteracted these alterations; however, they did so in a stronger manner when in combination. Genes involved in amyloid plaque processing (APP and TAU), synaptic function (Ache) and AD-related hyperphosphorylation were higher in HFD brains, and significantly downregulated in HFD-H, HFD-L and HFD-H + L. These results suggest that honey and limonene ingestion counteract obesity-related neurodegeneration and that joint consumption is more efficacious than a single administration.


Asunto(s)
Lesiones Encefálicas , Miel , Abejas , Ratones , Animales , Dieta Alta en Grasa , Limoneno , Ratones Obesos , Obesidad/metabolismo , Inflamación/metabolismo , Encéfalo/metabolismo , Lesiones Encefálicas/metabolismo , Ingestión de Alimentos , Ratones Endogámicos C57BL
3.
Int J Mol Sci ; 24(9)2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37176088

RESUMEN

The well-being of skin and mucous membranes is fundamental for the homeostasis of the body and thus it is imperative to treat any lesion quickly and correctly. In this view, polyphenols might assist and enhance a successful wound healing process by reducing the inflammatory cascade and the production of free radicals. However, they suffer from disadvantageous physico-chemical properties, leading to restricted clinical use. In this work, a complex mixture of PEGylated lipid, Glyceryl monoester, 18-ß-Glycyrrhetinic Acid and Menthol was designed to entrap Resveratrol (RSV) as the active ingredient and further produce lipid nanoparticles (LNPs) by homogenization followed by high-frequency sonication. The nanosystem was properly characterized in terms of particle size (DLS, SEM), zeta potential, drug loading, antioxidant power (DPPH), release behaviour, cytocompatibility, wound healing and antibiofilm properties. The optimized lipid mixture was homogeneous, melted at 57-61 °C and encapsulated amorphous RSV (4.56 ± 0.04% w/w). The RSV-loaded LNPs were almost monodispersed (PDI: 0.267 ± 0.010), with nanometric size (162.86 ± 3.12 nm), scavenger properties and suitable DR% and LE% values (96.82 ± 1.34% and 95.17 ± 0.25%, respectively). The release studies were performed to simulate the wound conditions: 1-octanol to mimic the lipophilic domains of biological tissues (where the First Order kinetic was observed) and citrate buffer pH 5.5 according to the inflammatory wound exudate (where the Korsmeyer-Peppas kinetic was followed). The biological and microbiological evaluations highlighted fibroblast proliferation and migration effects as well as antibiofilm properties at extremely low doses (LNPs: 22 µg/mL, corresponding to RSV 5 µM). Thus, the proposed multicomponent LNPs could represent a valuable RSV delivery platform for wound healing purposes.


Asunto(s)
Liposomas , Nanopartículas , Resveratrol/farmacología , Liposomas/farmacología , Nanopartículas/química , Lípidos/química , Proliferación Celular , Fibroblastos , Biopelículas , Tamaño de la Partícula
4.
Int J Mol Sci ; 24(11)2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37298104

RESUMEN

Oncogenic BRAF mutations have been widely described in melanomas and promote tumour progression and chemoresistance. We previously provided evidence that the HDAC inhibitor ITF2357 (Givinostat) targets oncogenic BRAF in SK-MEL-28 and A375 melanoma cells. Here, we show that oncogenic BRAF localises to the nucleus of these cells, and the compound decreases BRAF levels in both the nuclear and cytosolic compartments. Although mutations in the tumour suppressor p53 gene are not equally frequent in melanomas compared to BRAF, the functional impairment of the p53 pathway may also contribute to melanoma development and aggressiveness. To understand whether oncogenic BRAF and p53 may cooperate, a possible interplay was considered in the two cell lines displaying a different p53 status, being p53 mutated into an oncogenic form in SK-MEL-28 and wild-type in A375 cells. Immunoprecipitation revealed that BRAF seems to preferentially interact with oncogenic p53. Interestingly, ITF2357 not only reduced BRAF levels but also oncogenic p53 levels in SK-MEL-28 cells. ITF2357 also targeted BRAF in A375 cells but not wild-type p53, which increased, most likely favouring apoptosis. Silencing experiments confirmed that the response to ITF2357 in BRAF-mutated cells depends on p53 status, thus providing a rationale for melanoma-targeted therapy.


Asunto(s)
Melanoma , Proteínas Proto-Oncogénicas B-raf , Humanos , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/metabolismo , Mutación , Línea Celular Tumoral
5.
Int J Mol Sci ; 24(13)2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37446206

RESUMEN

Immunosenescence and inflammaging facilitate the insurgence of chronic diseases. The Mediterranean diet is a non-invasive intervention to improve the chronic low-grade inflammatory status associated with aging. Olive oil oleuropein (OLE) and hydroxytyrosol (HT) demonstrated a controversial modulatory action on inflammation in vitro when tested at concentrations exceeding those detectable in human plasma. We studied the potential anti-inflammatory effects of OLE and HT at nutritionally relevant concentrations on peripheral blood mononuclear cells (PBMCs) as regards cell viability, frequency of leukocyte subsets, and cytokine release, performing an age-focused analysis on two groups of subjects: Adult (age 18-64 years) and Senior (age ≥ 65 years). OLE and HT were used alone or as a pre-treatment before challenging PBMCs with lipopolysaccharide (LPS). Both polyphenols had no effect on cell viability irrespective of LPS, but 5 µM HT had an LPS-like effect on monocytes, reducing the intermediate subset in Adult subjects. OLE and HT had no effect on LPS-triggered release of TNF-α, IL-6 and IL-8, but 5 µM HT reduced IL-10 secretion by PBMCs from Adult vs. Senior group. In summary, nutritionally relevant concentrations of OLE and HT elicit no anti-inflammatory effect and influence the frequency of immune cell subsets with age-related different outcomes.


Asunto(s)
Leucocitos Mononucleares , Alcohol Feniletílico , Adulto , Humanos , Adolescente , Adulto Joven , Persona de Mediana Edad , Anciano , Lipopolisacáridos/toxicidad , Polifenoles/farmacología , Alcohol Feniletílico/farmacología
6.
Int J Mol Sci ; 23(6)2022 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-35328440

RESUMEN

Human red blood cells (RBCs), senescent or damaged due to particular stress, can be removed by programmed suicidal death, a process called eryptosis. There are various molecular mechanisms underlying eryptosis. The most frequent is the increase in the cytoplasmic concentration of Ca2+ ions, later exposure of erythrocytes to oxidative stress, hyperosmotic shock, ceramide formation, stimulation of caspases, and energy depletion. Phosphatidylserine (PS) exposed by eryptotic RBCs due to interaction with endothelial CXC-Motiv-Chemokin-16/Scavenger-receptor, causes the RBCs to adhere to vascular wall with consequent damage to the microcirculation. Eryptosis can be triggered by various xenobiotics and endogenous molecules, such as high cholesterol levels. The possible diseases associated with eryptosis are various, including anemia, chronic kidney disease, liver failure, diabetes, hypertension, heart failure, thrombosis, obesity, metabolic syndrome, arthritis, and lupus. This review addresses and collates the existing ex vivo and animal studies on the inhibition of eryptosis by food-derived phytochemicals and natural compounds including phenolic compounds (PC), alkaloids, and other substances that could be a therapeutic and/or co-adjuvant option in eryptotic-driven disorders, especially if they are introduced through the diet.


Asunto(s)
Anemia , Eriptosis , Anemia/metabolismo , Animales , Calcio/metabolismo , Eritrocitos/metabolismo , Humanos , Estrés Oxidativo/fisiología , Fosfatidilserinas/metabolismo , Fitoquímicos/metabolismo , Fitoquímicos/farmacología
7.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36499060

RESUMEN

Eryptosis is a physiological mechanism for the clearance of senescent or damaged erythrocytes by phagocytes. Excessive eryptosis is stimulated under several pathologies and associated with endothelial injury and thrombosis. Cigarette smoke (CS) is an established risk factor for vascular diseases and cigarette smokers have high-levels of eryptotic erythrocytes. This study, for the first time, investigates the mechanism by which CS damages red blood cells (RBCs). CS extract (CSE) from commercial cigarettes was prepared and standardized for nicotine content. Cytofluorimetric analysis demonstrated that treatment of human RBCs with CSE caused dose-dependent, phosphatidylserine externalization and cell shrinkage, hallmarks of apoptotic death. CSE did not affect cellular levels of Ca2+, reactive oxygen species (ROS) or glutathione (GSH). Immununoprecipitation and immunoblotting revealed the assembly of the death-inducing signaling complex (DISC) and oligomerization of Fas receptor as well as cleaved caspase-8 and caspase-3 within 6 h from the treatment. At the same time-interval, CSE elicited neutral sphyngomielinase (nSMase) activity-dependent ceramide formation and phosphorylation of p38 MAPK. Through specific inhibitors' nSMase, caspase-8 or p38 MAPK activities, we demonstrated that p38 MAPK activation is required for caspase-8-mediated eryptosis and that ceramide generation is initiator caspase-dependent. Finally, ex vivo analysis detected phosphorylated p38 MAPK (p-p38) and Fas-associated signaling complex in erythrocytes from cigarette smokers. In conclusion, our study demonstrates that CSE exposure induces in erythrocytes an extrinsic apoptotic pathway involving p38 MAPK-initiated DISC formation followed by activation of caspase-8/caspase-3 via ceramide formation.


Asunto(s)
Eriptosis , Humo , Proteínas Quinasas p38 Activadas por Mitógenos , Humanos , Caspasa 3/metabolismo , Caspasa 8/metabolismo , Ceramidas/metabolismo , Eritrocitos/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Nicotiana/efectos adversos , Humo/efectos adversos
8.
Int J Mol Sci ; 24(1)2022 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-36613822

RESUMEN

Aging is associated with a low-grade, systemic inflammatory state defined as "inflammaging", ruled by the loss of proper regulation of the immune system leading to the accumulation of pro-inflammatory mediators. Such a condition is closely connected to an increased risk of developing chronic diseases. A number of studies demonstrate that olive oil phenolic compound oleuropein and its derivative hydroxytyrosol contribute to modulating tissue inflammation and oxidative stress, thus becoming attractive potential candidates to be used in the context of nutraceutical interventions, in order to ameliorate systemic inflammation in aging subjects. In this review, we aim to summarize the available data about the anti-inflammatory properties of oleuropein and hydroxytyrosol, discussing them in the light of molecular pathways involved in the synthesis and release of inflammatory mediators in inflammaging.


Asunto(s)
Mediadores de Inflamación , Alcohol Feniletílico , Humanos , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Glucósidos Iridoides , Aceite de Oliva , Alcohol Feniletílico/farmacología , Inflamación/tratamiento farmacológico , Iridoides/farmacología , Iridoides/uso terapéutico
9.
Phytother Res ; 35(3): 1432-1442, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33058354

RESUMEN

Malignant melanoma is the deadliest skin cancer, due to its propensity to metastasize. MAPKs and NF-κB pathways are constitutively activated in melanoma and promote cell proliferation, cell invasion, metastasis formation, and resistance to therapeutic regimens. Thus, they represent potential targets for melanoma prevention and treatment. Phytochemicals are gaining considerable attention for the management of melanoma because of their several cellular and molecular targets. A screening of a small library of sesquiterpenes lactones selected cynaropicrin, isolated from the aerial parts of Centaurea drabifolia subsp. detonsa, for its potential anticancer effect against melanoma cells. Treatment of human melanoma cells A375 with cynaropicrin resulted in inhibition of cell proliferation and induction of caspase-3-dependent apoptosis. Furthermore, cynaropicrin reduced several cellular malignant features such migration, invasion, and colonies formation through the inhibition of ERK1/2 and NF-κB activity. Cynaropicrin was able to reduce intracellular reactive oxygen species generation, which are involved in all the stages of carcinogenesis. Indeed, cynaropicrin increased the expression of several antioxidant genes, such as glutamate-cysteine ligase and heme oxygenase-1, by promoting the activation of the transcription factor Nrf-2. In conclusion, our results individuate cynaropicrin as a potential adjuvant chemotherapeutic agent for melanoma by targeting several protumorigenic signaling pathways.


Asunto(s)
Lactonas/uso terapéutico , Melanoma/tratamiento farmacológico , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Sesquiterpenos/uso terapéutico , Apoptosis , Proliferación Celular , Progresión de la Enfermedad , Humanos , Lactonas/farmacología , Sesquiterpenos/farmacología , Transducción de Señal
10.
Int J Mol Sci ; 22(7)2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33806203

RESUMEN

Herein, we assessed the effect of full native peptide of amyloid-beta (Aß) (1-42) and its fragments (25-35 and 35-25) on tissue transglutaminase (TG2) and its isoforms (TG2-Long and TG2-Short) expression levels on olfactory ensheathing cells (OECs). Vimentin and glial fibrillary acid protein (GFAP) were also studied. The effect of the pre-treatment with indicaxanthin from Opuntia ficus-indica fruit on TG2 expression levels and its isoforms, cell viability, total reactive oxygen species (ROS), superoxide anion (O2-), and apoptotic pathway activation was assessed. The levels of Nestin and cyclin D1 were also evaluated. Our findings highlight that OECs exposure to Aß(1-42) and its fragments induced an increase in TG2 expression levels and a different expression pattern of its isoforms. Indicaxanthin pre-treatment reduced TG2 overexpression, modulating the expression of TG2 isoforms. It reduced total ROS and O2- production, GFAP and Vimentin levels, inhibiting apoptotic pathway activation. It also induced an increase in the Nestin and cyclin D1 expression levels. Our data demonstrated that indicaxanthin pre-treatment stimulated OECs self-renewal through the reparative activity played by TG2. They also suggest that Aß might modify TG2 conformation in OECs and that indicaxanthin pre-treatment might modulate TG2 conformation, stimulating neural regeneration in Alzheimer's disease.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Betaxantinas/farmacología , Proteínas de Unión al GTP/metabolismo , Regulación Enzimológica de la Expresión Génica , Bulbo Olfatorio/metabolismo , Piridinas/farmacología , Transglutaminasas/metabolismo , Enfermedad de Alzheimer/metabolismo , Animales , Apoptosis , Diferenciación Celular , Ciclina D1/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Ratones , Regeneración Nerviosa , Nestina/metabolismo , Opuntia/química , Estrés Oxidativo , Proteína Glutamina Gamma Glutamiltransferasa 2 , Isoformas de Proteínas , Especies Reactivas de Oxígeno/metabolismo , Vimentina/metabolismo
11.
BMC Nurs ; 20(1): 124, 2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34233674

RESUMEN

BACKGROUND: The efficient management of relational competences in healthcare professionals is crucial to ensuring that a patient's treatment and care process is conducted positively. Empathy is a major component of the relational skills expected of health professionals. Knowledge of undergraduate healthcare students' empathic abilities is important for educators in designing specific and efficient educational programmes aimed at supporting or enhancing such competences. In this study, we measured first-year undergraduate nursing students' attitudes towards professional empathy in clinical encounters. The students' motivations for entering nursing education were also evaluated. This study takes a multi-method approach based on the use of qualitative and quantitative tools to examine the association between students' positive attitudes towards the value of empathy in health professionals and their prosocial and altruistic motivations in choosing to engage in nursing studies. METHODS: A multi-method study was performed with 77 first-year nursing students. The Jefferson Scale of Empathy (JSE) - Health Professions Student Version was administered. Students' motivations for choosing nursing studies were detected through an open question and thematically analysed. Using explorative factor analysis and principal component analysis, a dimensional reduction was conducted to identify subjects with prosocial and altruistic motivations. Finally, linear models were tested to examine specific associations between motivation and empathy. RESULTS: Seven distinct themes distinguishing internal and external motivational factors were identified through a thematic analysis of students' answers regarding their decision to enter a nursing degree course. Female students gained higher scores on the empathy scale than male ones. When students' age was considered, this difference was only observed for younger students, with young females' total scores being higher than young males'. High empathy scores were positively associated with altruistic motivational factors. A negative correlation was found between external motivational factors and the scores of the Compassionate Care subscale of the JSE. CONCLUSIONS: Knowing the level of nursing students' empathy and their motivational factors for entering nursing studies is important for educators to implement training paths that enhance students' relational attitudes and skills and promote the positive motivational aspects that are central to this profession.

12.
Molecules ; 25(21)2020 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-33143282

RESUMEN

Manna is produced from the spontaneous solidification of the sap of some Fraxinus species, and, owing its content in mannitol, is used in medicine as a mild laxative. Manna is also a rich source of characteristic bio-phenols with reducing, antioxidant and anti-inflammatory properties. This study assesses the activity of a hydrophilic extract of manna (HME) on cellular and molecular events in human colon-rectal cancer cells. HME showed a time- and concentration-dependent anti-proliferative activity, measured by MTT assay, in all the cell lines examined, namely Caco-2, HCT-116 and HT-29. The amounts of HME that caused 50% of cell death after a 24 h treatment were 8.51 ± 0.77, 10.73 ± 1.22 and 28.92 ± 1.99 mg manna equivalents/mL, respectively; no toxicity was observed in normally differentiated Caco-2 intestinal cells. Hydroxytyrosol, a component of HME known for its cytotoxic effects on colon cancer cells, was ineffective, at least at the concentration occurring in the extract. Through flow-cytometric techniques and Western blot analysis, we show that HME treatment causes apoptosis, assessed by phosphatidylserine exposure, as well as a loss of mitochondrial membrane potential, an intracellular formation of reactive oxygen species (ROS), increases in the levels of cleaved PARP-1, caspase 3 and Bax, and a decrease in Bcl-2 expression. Moreover, HME interferes with cell cycle progression, with a block at the G1/S transition. In conclusion, the phytocomplex extracted from manna exerts an anti-proliferative activity on human colon cancer cells through the activation of mitochondrial pathway-mediated apoptosis and cell cycle arrest. Our data may suggest that manna could have the potential to exert chemo-preventive effects for the intestine.


Asunto(s)
Antineoplásicos Fitogénicos , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Fraxinus/química , Mitocondrias/metabolismo , Extractos Vegetales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Células CACO-2 , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HT29 , Humanos , Mitocondrias/patología , Proteínas de Neoplasias/biosíntesis , Extractos Vegetales/química , Extractos Vegetales/farmacología
13.
Cell Physiol Biochem ; 53(6): 933-947, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31805226

RESUMEN

BACKGROUND/AIMS: We showed that patho-physiological concentrations of either 7-keto-cholesterol (7-KC), or cholestane-3beta, 5alpha, 6beta-triol (TRIOL) caused the eryptotic death of human red blood cells (RBC), strictly dependent on the early production of reactive oxygen species (ROS). The goal of the current study was to assess the contribution of the erythrocyte ROS-generating enzymes, NADPH oxidase (RBC-NOX), nitric oxide synthase (RBC-NOS) and xanthine oxido-reductase (XOR) to the oxysterol-dependent eryptosis and pertinent activation pathways. METHODS: Phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, reactive oxygen/nitrogen species (RONS) and nitric oxide formation from 2',7'-dichloro-dihydrofluorescein (DCF-DA) and 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate (DAF-FM DA) -dependent fluorescence, respectively; Akt1, phospho-NOS3 Ser1177, and PKCζ from Western blot analysis. The activity of individual 7-KC (7 µM) and TRIOL (2, µM) on ROS-generating enzymes and relevant activation pathways was assayed in the presence of Diphenylene iodonium chloride (DPI), N-nitro-L-arginine methyl ester (L-NAME), allopurinol, NSC23766 and LY294002, inhibitors in this order of RBC-NOX, RBC-NOS, XOR and upstream regulatory proteins Rac GTPase and phosphoinositide3 Kinase (PI3K); hemoglobin oxidation from spectrophotometric analysis. RESULTS: RBC-NOX was the target of 7-KC, through a signaling including Rac GTPase and PKCζ, whereas TRIOL caused activation of RBC-NOS according to the pathway PI3K/Akt, with the concurrent activity of a Rac-GTPase. In concomitance with the TRIOL-induced .NO production, formation of methemoglobin with global loss of heme were observed, ascribable to nitrosative stress. XOR, activated after modification of the redox environment by either RBC-NOX or RBC-NOS activity, concurred to the overall oxidative/nitrosative stress by either oxysterols. When 7-KC and TRIOL were combined, they acted independently and their effect on ROS/RONS production and PS exposure appeared the result of the effects of the oxysterols on RBC-NOX and RBC-NOS. CONCLUSION: Eryptosis of human RBCs may be caused by either 7-KC or TRIOL by oxidative/nitrosative stress through distinct signaling cascades activating RBC-NOX and RBC-NOS, respectively, with the complementary activity of XOR; when combined, the oxysterols act independently and both concur to the final eryptotic effect.


Asunto(s)
Colestanoles/farmacología , Eriptosis/efectos de los fármacos , Cetocolesteroles/farmacología , NADPH Oxidasas/metabolismo , Óxido Nítrico Sintasa/metabolismo , Eritrocitos/citología , Eritrocitos/metabolismo , Hemoglobinas/química , Humanos , Oxidación-Reducción , Fosfatidilinositol 3-Quinasas/química , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas de Unión al GTP rac/antagonistas & inhibidores , Proteínas de Unión al GTP rac/metabolismo
14.
BMC Med Educ ; 19(1): 192, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-31182080

RESUMEN

BACKGROUND: The nursing shortage is of worldwide concern, with nursing student retention acknowledged as a priority. As a fundamental step towards exploring factors that can guide the implementation of strategic approaches to retain undergraduate nursing students and prevent their attrition, the aim of this study is to examine the motivation for choosing nursing studies of first-year nursing students within the theoretical framework of self-determination theory. METHODS: We conducted a study at the Medical School of the University of Palermo. A total of 133 first-year nursing students completed a two-part questionnaire: a measure of socio-demographic aspects and an open question about their motivation for choosing nursing studies. Students' responses were analysed using thematic analysis. Dimensional analysis was performed in order to verify an organization along one dimension, in agreement with the differentiation of the autonomous and controlled types of motivation of self-determination theory. A person-centred approach was utilised to define motivational profiles able to characterize clusters of students according to both quality and quantity of motivation. RESULTS: A set of 18 categories was developed. The factor analysis has shown that nursing students' motivations can be organized along one dimension, in alignment with the differentiation of the autonomous and controlled forms of motivation of self-determination theory. Through adoption of a person-centred approach, four motivational profiles were identified: a) students with good quality motivation profile (high autonomous and low controlled); b) students with poor quality motivation profile (low autonomous and high controlled); c) students with low quantity motivation profile (low autonomous and low controlled); d) students with low quantity and poor quality motivation profile (i.e. prevalence of controlled motivation). CONCLUSIONS: Importance of this research includes the possibility to interpret nursing students' reasons within the theoretical framework of self-determination theory, a well-grounded model able to offer useful information to academic nursing schools, in order to promote effective strategies to foster and support student motivation.


Asunto(s)
Selección de Profesión , Motivación , Enfermería , Autonomía Personal , Adolescente , Adulto , Femenino , Humanos , Masculino , Teoría Psicológica , Autoinforme , Sicilia , Estudiantes de Enfermería/psicología , Encuestas y Cuestionarios , Adulto Joven
15.
J Sci Food Agric ; 99(9): 4242-4247, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30801716

RESUMEN

BACKGROUND: The stems of Opuntia ficus-indica, known as cladodes, are a rich source of soluble fibers, which makes them an important candidate for the production of functional foods. Tagliatelle of durum wheat fortified with Opuntia cladode extract (OCE) at different levels of addition (10-30%, v/w) was prepared on a laboratory scale and quality characteristics and sensory acceptability were assessed. RESULTS: The main quality parameters (optimal cooking time, swelling index, cooking loss, dry matter) and sensory analysis on a nine-point hedonic scale were comparable with those of the control pasta sample (no added OCE) when durum wheat was supplemented with OCE at up to 20% (v/w). An in vitro human simulated gastrointestinal digestion in the presence of cholesterol or its main dietary oxidized derivative, 7-ketocholesterol, showed that OCE-fortified pasta strongly reduced the bioaccessibility of both the sterols (the higher the incorporated OCE level, the higher the effect). Moreover the extent of starch digestion decreased with increasing levels of OCE. CONCLUSION: The results of the present study indicate that OCE-fortified pasta comprises a food with healthy properties, such as blood cholesterol- and glucose-lowering capabilities. © 2019 Society of Chemical Industry.


Asunto(s)
Alimentos Fortificados/análisis , Alimentos Funcionales/análisis , Opuntia/química , Extractos Vegetales/análisis , Extractos Vegetales/metabolismo , Triticum/química , Adulto , Anciano , Culinaria , Fibras de la Dieta/análisis , Fibras de la Dieta/metabolismo , Digestión , Femenino , Tracto Gastrointestinal/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Opuntia/metabolismo , Control de Calidad , Gusto , Triticum/metabolismo , Adulto Joven
16.
Br J Nutr ; 114(3): 368-75, 2015 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-26169206

RESUMEN

Toxic oxysterols in a hypercholesterolaemia-relevant proportion cause suicidal death of human erythrocytes or eryptosis. This process proceeds through early production of reactive oxygen species (ROS), release of prostaglandin (PGE2) and opening of PGE2-dependent Ca channels, membrane phosphatidylserine (PS) externalisation, and cell shrinkage. The present study was the first to reveal that a bioavailable phytochemical, indicaxanthin (Ind) from cactus pear fruit, in a concentration range (1.0-5.0 µM) consistent with its plasma level after a fruit meal, prevents PS externalisation and cell shrinkage in a dose-dependent manner when incubated with isolated healthy human erythrocytes exposed to an oxysterol mixture for 48 h. Dietary Ind inhibited ROS production, glutathione (GSH) depletion, PGE2 release and Ca2+ entry. Ind alone did not modify the erythrocyte redox environment or affect other parameters. Ex vivo spiking of normal human blood with the oxysterol mixture for 48 h induced eryptosis, resulting in the production of ROS and decreased levels of GSH, which was prevented by concurrent exposure to 5 µm-Ind. The adherence of eryptotic erythrocytes to the endothelium causes vascular tissue injury. Erythrocytes isolated from blood incubated with the oxysterol mixture plus 5 µm-Ind did not adhere to endothelial cell monolayers. Eryptotic erythrocytes may contribute to thrombotic complications in hypercholesterolaemia. Our findings suggest the positive effects of diets containing Ind on erythrocytes in hypercholesterolaemic subjects.


Asunto(s)
Betaxantinas/administración & dosificación , Dieta , Células Endoteliales/fisiología , Eritrocitos/efectos de los fármacos , Hipercolesterolemia/sangre , Opuntia/química , Piridinas/administración & dosificación , Calcio/sangre , Adhesión Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Dinoprostona/sangre , Eritrocitos/fisiología , Frutas/química , Glutatión/sangre , Células Endoteliales de la Vena Umbilical Humana , Humanos , Fosfatidilserinas/sangre , Especies Reactivas de Oxígeno/sangre , Esteroles/farmacología
17.
BMC Med Educ ; 15: 182, 2015 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-26498207

RESUMEN

BACKGROUND: This study is based on the evidence that tests can be used as an educational tool to enhance learning, not just as an evaluation tool. There is a growing body of research that shows that participating in repeated testing improves learning, a phenomenon defined as Test-Enhanced Learning. The aim of the present study was to analyse the effect of the use of a test enhanced learning program integrated into a general psychology course for undergraduate nursing students and its interaction with the students' test anxiety. METHODS: 161 undergraduate nursing students attending a General Psychology course followed an educational program based on Test-Enhanced Learning methodology. Students were divided into two groups, an experimental group (TEL group) and a control group (Re-study group). TEL students took a multiple-choice test on the lecture topics. The Re-study group just read study material. Testing and re-study occurred at intervals of about a week after each lesson. TEL students received feedback immediately after each test. About two weeks after the end of the lessons, all the students took a final cumulative test on all the topics. Statistical analysis was used to analyse students' performances. After the administration of the cumulative unit test, all the students took a graded examination. RESULTS: Students in the TEL group performed better than the controls, both in the final cumulative test and in a graded examination. TEL participants experienced better final cumulative test results than students not tested (M TEL = 23.11, M Re-study = 20.47, t(109.86) = -2.57, p < 0.05, r = 0.24). Test-Enhanced Learning program participation has a positive impact on exam performance (ßG_Step1 = 0.46, p < 0.001). Finally, the analysis performed shows a slight moderating effect of test anxiety on Test-Enhanced Learning (ßGxTA_Step3 = 0.15, p < 0.05). DISCUSSION AND CONCLUSIONS: Test-Enhanced Learning can be an effective tool for promoting and enhancing learning. In fact, taking tests after studying produced better long-term retention and then better final test performance than re-reading without testing. Both students in the TEL group and the Re-study group with a high test anxiety level perform less well than colleagues with lower test anxiety. Nevertheless, students with higher test anxiety may obtain more benefits from participating in a Test-Enhanced Learning process than people with lower test anxiety. Further studies on larger and more representative samples are necessary in order to investigate the effect of test anxiety on Test-Enhanced Learning.


Asunto(s)
Habilidades para Tomar Exámenes , Curriculum , Educación en Enfermería/métodos , Evaluación Educacional/métodos , Femenino , Humanos , Italia , Masculino , Aprendizaje Basado en Problemas , Estudiantes de Enfermería/estadística & datos numéricos , Adulto Joven
18.
Cell Physiol Biochem ; 34(4): 1075-89, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25228229

RESUMEN

BACKGROUND/AIMS: Oxysterol activity on the erythrocyte (RBC) programmed cell death (eryptosis) had not been studied yet. Effects of an oxysterol mixture in hyper-cholesterolemic-relevant proportion, and of individual compounds, were investigated on RBCs from healthy humans. METHODS: Membrane phosphatidylserine (PS) externalization, calcium entry, ROS production, amino-phospholipid translocase (APLT) activity were evaluated by cytofluorimetric assays, cell volume from forward scatter. Prostaglandin PGE2 was measured by ELISA; GSH-adducts and lipoperoxides by spectrophotometry. Involvement of protein kinase C and caspase was investigated by inhibitors staurosporin, calphostin C, and Z-DEVD-FMK, respectively. RESULTS: Oxysterols caused PS externalization and cell shrinkage, associated with PGE2release, opening of PGE2-dependent calcium channels, ROS production, GSH depletion, membrane lipid oxidation. Addition of antioxidants prevented Ca(2+) influx and eryptosis. Calcium removal prevented cell shrinkage, with small effect (-20%) on the PS exposure, whereas ROS generation was unaltered. Either in the presence or absence of calcium i) oxysterols inhibited APLT, ii) staurosporin, calphostin C, Z-DEVD-FMK blunted and iii) antioxidants fully prevented the oxysterol-induced PS externalization. Only 7-ketocholesterol and cholestan-3ß,5α,6ß-triol were individually active. Eryptosis was observed in RBCs isolated after ex vivo spiking of human whole blood with the oxysterol mixture. CONCLUSIONS: Oxysterols induce an oxidative stress-dependent eryptosis, involving calcium-independent mechanisms. Eryptotic activity of oxysterols may be relevant in vivo.


Asunto(s)
Apoptosis/fisiología , Eritrocitos/metabolismo , Eritrocitos/patología , Hipercolesterolemia/patología , Estrés Oxidativo/fisiología , Antioxidantes/metabolismo , Calcio/metabolismo , Canales de Calcio/metabolismo , Caspasas/metabolismo , Dinoprostona/metabolismo , Humanos , Hipercolesterolemia/metabolismo , Cetocolesteroles/metabolismo , Fosfatidilserinas/metabolismo , Proteína Quinasa C/metabolismo , Especies Reactivas de Oxígeno/metabolismo
19.
J Nutr ; 144(2): 185-92, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24306215

RESUMEN

Nutritional research has shifted recently from alleviating nutrient deficiencies to chronic disease prevention. We investigated the activity of indicaxanthin, a bioavailable phytochemical of the betalain class from the edible fruit of Opuntia ficus-indica (L. Miller) in a rat model of acute inflammation. Rat pleurisy was achieved by injection of 0.2 mL of λ-carrageenin in the pleural cavity, and rats were killed 4, 24, and 48 h later; exudates were collected to analyze inflammatory parameters, such as nitric oxide (NO), prostaglandin E(2) (PGE(2)), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α); cells recruited in pleura were analyzed for cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS) expression, and nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activation. Indicaxanthin (0.5, 1, or 2 µmol/kg), given orally before carrageenin, time- and dose-dependently, reduced the exudate volume (up to 70%) and the number of leukocytes recruited in the pleural cavity (up to 95%) at 24 h. Pretreatment with indicaxanthin at 2 µmol/kg inhibited the carrageenin-induced release of PGE(2) (91.4%), NO (67.7%), IL-1ß (53.6%), and TNF-α (71.1%), and caused a decrease of IL-1ß (34.5%), TNF-α (81.6%), iNOS (75.2%), and COX2 (87.7%) mRNA, as well as iNOS (71.9%) and COX-2 (65.9%) protein expression, in the recruited leukocytes. Indicaxanthin inhibited time- and dose- dependently the activation of NF-κB, a key transcription factor in the whole inflammatory cascade. A pharmacokinetic study with a single 2 µmol/kg oral administration showed a maximum 0.22 ± 0.02 µmol/L (n = 15) plasma concentration of indicaxanthin, with a half-life of 1.15 ± 0.11 h. When considering the high bioavailability of indicaxanthin in humans, our findings suggest that this dietary pigment has the potential to improve health and prevent inflammation-based disorders.


Asunto(s)
Antiinflamatorios/uso terapéutico , Betaxantinas/uso terapéutico , Mediadores de Inflamación/metabolismo , Inflamación/dietoterapia , Opuntia/química , Fitoterapia , Pleuresia/dietoterapia , Piridinas/uso terapéutico , Animales , Antiinflamatorios/farmacología , Betaxantinas/farmacología , Carragenina , Modelos Animales de Enfermedad , Frutas/química , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Leucocitos/metabolismo , Masculino , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Cavidad Pleural/efectos de los fármacos , Cavidad Pleural/metabolismo , Pleuresia/inducido químicamente , Pleuresia/tratamiento farmacológico , Pleuresia/metabolismo , Piridinas/farmacología , ARN Mensajero/metabolismo , Ratas , Ratas Wistar
20.
Biofactors ; 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520710

RESUMEN

A physiological mechanism of programmed cell death called eryptosis occurs in aged or damaged red blood cells (RBCs). Dysregulated eryptosis contributes to abnormal microcirculation and prothrombotic risk. Cigarette smoke extract (CSE) induces a p38 MAPK-initiated, Fas-mediated eryptosis, activating the death-inducing signaling complex (DISC). Indicaxanthin (Ind) from cactus pear fruits, is a bioavailable dietary phytochemical in humans and it is able to incorporate into RBCs enhancing their defense against numerous stimuli. This in vitro work shows that Ind, at concentrations that mimic plasma concentrations after a fruit meal, protects erythrocytes from CSE-induced eryptosis. CSE from commercial cigarettes was prepared in aqueous solution using an impinger air sampler and nicotine content was determined. RBCs were treated with CSE for 3 h in the absence or presence of increasing concentrations of Ind (from 1 to 5 µM). Cytofluorimetric measurements indicated that Ind reduced CSE-induced phosphatidylserine externalization and ceramide formation in a concentration-dependent manner. Confocal microscopy visualization and coimmunoprecipitation experiments revealed that Ind prevented both CSE-triggered Fas aggregation and FasL/FADD/caspase 8 recruitment in the membrane, indicating inhibition of DISC assembly. Ind inhibited the phosphorylation of p38 MAPK, caspase-8/caspase-3 cleavage, and caspase-3 activity induced by CSE. Finally, Ind reduced CSE-induced ATP depletion and restored aminophospholipid translocase activity impaired by CSE treatment. In conclusion, Ind concentrations comparable to nutritionally relevant plasma concentrations, can prevent Fas-mediated RBC death signaling induced by CSE, which suggests that dietary intake of cactus pear fruits may limit the deleterious effects of cigarette smoking.

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