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1.
Int J Mol Sci ; 25(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338838

RESUMO

Dysfunctions of lipid metabolism are associated with tumor progression and treatment resistance of cutaneous melanoma. BRAF/MEK inhibitor resistance is linked to alterations of melanoma lipid pathways. We evaluated whether a specific lipid pattern characterizes plasma from melanoma patients and their response to therapy. Plasma samples from patients and controls were analyzed for FASN and DHCR24 levels and lipidomic profiles. FASN and DHCR24 expression resulted in association with disease condition and related to plasma cholesterol and triglycerides in patients at different disease stages (n = 144) as compared to controls (n = 115). Untargeted lipidomics in plasma (n = 40) from advanced disease patients and controls revealed altered levels of different lipids, including fatty acid derivatives and sphingolipids. Targeted lipidomics identified higher levels of dihydroceramides, ceramides, sphingomyelins, ganglioside GM3, sphingosine, sphingosine-1-phosphate, and dihydrosphingosine, saturated and unsaturated fatty acids. When melanoma patients were stratified based on a long/short-term clinical response to kinase inhibitors, differences in plasma levels were shown for saturated fatty acids (FA 16:0, FA18:0) and oleic acid (FA18:1). Our results associated altered levels of selected lipid species in plasma of melanoma patients with a more favorable prognosis. Although obtained in a small cohort, these results pave the way to lipidomic profiling for melanoma patient stratification.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/tratamento farmacológico , Ácidos Graxos/metabolismo , Esfingolipídeos , Triglicerídeos
2.
Proc Natl Acad Sci U S A ; 117(24): 13393-13398, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32482856

RESUMO

Climate engineering-the deliberate large-scale manipulation of the Earth's climate system-is a set of technologies for reducing climate-change impacts and risks. It is controversial and raises novel governance challenges [T. C. Schelling, Climatic Change, 33, 303-307 (1996); J. Virgoe, Climatic Change, 95, 103-119 (2008)]. We focus on the strategic implications of solar geoengineering. When countries engineer the climate, conflict can arise because different countries might prefer different temperatures. This would result in too much geoengineering: the country with the highest preference for geoengineering cools the planet beyond what is socially optimal at the expense of the others-a theoretical possibility termed "free-driving" [M. L. Weitzman, Scand. J. Econ., 117, 1049-1068 (2015)]. This study is an empirical test of this hypothesis. We carry out an economic laboratory experiment based on a public "good or bad" game. We find compelling evidence of free-driving: global geoengineering exceeds the socially efficient level and leads to welfare losses. We also evaluate the possibility of counteracting the geoengineering efforts of others. Results show that countergeoengineering generates high payoff inequality as well as heavy welfare losses, resulting from both strategic and behavioral factors. Finally, we compare strategic behavior in bilateral and multilateral settings. We find that welfare deteriorates even more under multilateralism when countergeoengineering is a possibility. These results have general implications for governing global good or bad commons.

3.
Exp Eye Res ; 207: 108601, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33910035

RESUMO

Electrical stimulation (ES) of the eye represents a therapeutic approach in various clinical applications ranging from retinal dystrophies, age-related macular degeneration, retinal artery occlusion and nonarteritic ischemic optic neuropathy. In clinical practice, ES of the eye is mainly performed with a transcorneal or transpalpebral approach. These procedures are non-invasive and well-tolerated by the patients, reporting only minimal and transient adverse events, while serious adverse effects were not observed. Despite the growing literature on animal models, only clinical parameters have been investigated in humans and few data are available about biochemical changes induced by ES of the eye. The purpose of this study is to investigate the possible mechanism that regulates the beneficial effects of ES on retinal cells function and survival in humans. 28 patients undergoing pars plana vitrectomy (PPV) for idiopathic epiretinal membrane (iERM) were randomly divided in two groups: 13 patients were treated with transpalpebral ES before surgery and 15 underwent surgery with no prior treatment. Vitreous samples were collected for biochemical analysis during PPV. ES treatment leads to a reduction in the vitreous expression of both proinflammatory cytokines, namely IL-6 and IL-8, and proinflammatory lipid mediators, such as lysophosphatidylcholine. Indeed, we observed a 70% decrease of lysophosphatidylcholine 18:0, which has been proven to exert the greatest proinflammatory activities among the lysophosphatidylcholine class. The content of triglycerides is also affected and significantly decreased following ES application. The vitreous composition of patients undergoing PPV for iERM displays significant changes following ES treatment. Proinflammatory cytokines and bioactive lipid mediators expression decreases, suggesting an overall anti-inflammatory potential of ES. The investigation of the mechanism by which this treatment alters the retinal neurons leading to good outcomes is essential for supporting ES therapeutic application in various types of retinal diseases.


Assuntos
Citocinas/metabolismo , Terapia por Estimulação Elétrica , Membrana Epirretiniana/terapia , Lisofosfatidilcolinas/metabolismo , Triglicerídeos/metabolismo , Corpo Vítreo/metabolismo , Idoso , Idoso de 80 Anos ou mais , Ensaio de Imunoadsorção Enzimática , Membrana Epirretiniana/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas por Ionização por Electrospray , Vitrectomia
4.
Acta Neurochir (Wien) ; 163(3): 689-697, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-31950268

RESUMO

BACKGROUND: Skull base chordomas (SBC) are rare malignant tumors and few factors have been found to be reliable markers for clinical decision making and survival prognostication. The aim of the present work was to identify specific prognostic factors potentially useful for the management of SBC patients. METHODS: A retrospective review of all the patients diagnosed and treated for SBC at the Fondazione IRCCS Istituto Neurologico "Carlo Besta" between January 1992 and December 2017 has been performed. Survival analysis was performed and a logistic regression model was used. Statistically significant predictors were rated based on their log odds in order to preliminarily build a personalized grading scale-the Peri-Operative Chordoma Scale (POCS). RESULTS: Fifty-nine primary chordoma patients were included. The average follow-up from the first treatment was 82.6 months (95% CI, 65.5-99.7). POCS was built over PFS and MR contrast enhancement (intense vs mild/no, value 4), preoperative motor deficit (yes vs no, value 3), and the development of any postoperative complications (yes vs no, value 2). POCS ranges between 0 and 9, with higher scores being associated with reduced likelihood of survival and progression-free state. CONCLUSIONS: Our results show that preoperative clinical symptoms (motor deficits), surgical features (extent of tumor resection and surgeon's experience), development of postoperative complications, and KPS decline represent significant prognostic factors. The degree of MR contrast enhancement significantly correlated to both OS and PFS. We also preliminarily developed the POCS as a prognostic grading scale which may help neurosurgeons in the personalized management of patients undergoing potential adjuvant therapies.


Assuntos
Cordoma/cirurgia , Complicações Pós-Operatórias/epidemiologia , Neoplasias da Base do Crânio/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Período Pré-Operatório
5.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208778

RESUMO

Parkinson's disease (PD) is a proteinopathy associated with the aggregation of α-synuclein and the formation of lipid-protein cellular inclusions, named Lewy bodies (LBs). LB formation results in impaired neurotransmitter release and uptake, which involve membrane traffic and require lipid synthesis and metabolism. Lipids, particularly ceramides, are accumulated in postmortem PD brains and altered in the plasma of PD patients. Autophagy is impaired in PD, reducing the ability of neurons to clear protein aggregates, thus worsening stress conditions and inducing neuronal death. The inhibition of ceramide synthesis by myriocin (Myr) in SH-SY5Y neuronal cells treated with preformed α-synuclein fibrils reduced intracellular aggregates, favoring their sequestration into lysosomes. This was associated with TFEB activation, increased expression of TFEB and LAMP2, and the cytosolic accumulation of LC3II, indicating that Myr promotes autophagy. Myr significantly reduces the fibril-related production of inflammatory mediators and lipid peroxidation and activates NRF2, which is downregulated in PD. Finally, Myr enhances the expression of genes that control neurotransmitter transport (SNARE complex, VMAT2, and DAT), whose progressive deficiency occurs in PD neurodegeneration. The present study suggests that counteracting the accumulation of inflammatory lipids could represent a possible therapeutic strategy for PD.


Assuntos
Ceramidas/biossíntese , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Animais , Vias Biossintéticas/efeitos dos fármacos , Linhagem Celular Tumoral , Gerenciamento Clínico , Suscetibilidade a Doenças , Ácidos Graxos Monoinsaturados/metabolismo , Humanos , Espaço Intracelular/metabolismo , Estresse Oxidativo , Doença de Parkinson/tratamento farmacológico , Esfingolipídeos/metabolismo
6.
Int J Mol Sci ; 23(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35008487

RESUMO

Peripheral nerve sheath tumors (PNSTs) include schwannomas, neurofibromas (NFs), and plexiform neurofibromas (PNFs), among others. While they are benign tumors, according to their biological behavior, some have the potential for malignant degeneration, mainly PNFs. The specific factors contributing to the more aggressive behavior of some PNSTs compared to others are not precisely known. Considering that lipid homeostasis plays a crucial role in fibrotic/inflammatory processes and in several cancers, we hypothesized that the lipid asset was also unbalanced in this group of nerve tumors. Through untargeted lipidomics, NFs presented a significant increase in ceramide, phosphatidylcholine, and Vitamin A ester. PNFs displayed a marked decrease in 34 out of 50 lipid class analyzed. An increased level of ether- and oxidized-triacylglycerols was observed; phosphatidylcholines were reduced. After sphingolipidomic analysis, we observed six sphingolipid classes. Ceramide and dihydroceramides were statistically increased in NFs. All the glycosylated species appeared reduced in NFs, but increased in PNFs. Our findings suggested that different subtypes of PNSTs presented a specific modulation in the lipidic profile. The untargeted and targeted lipidomic approaches, which were not applied until now, contribute to better clarifying bioactive lipid roles in PNS natural history to highlight disease molecular features and pathogenesis.


Assuntos
Lipídeos/fisiologia , Neoplasias de Bainha Neural/metabolismo , Neoplasias de Bainha Neural/patologia , Adulto , Idoso , Feminino , Homeostase/fisiologia , Humanos , Lipidômica/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Int J Mol Sci ; 22(24)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34948203

RESUMO

Moyamoya arteriopathy (MA) is a rare cerebrovascular disorder characterized by ischemic/hemorrhagic strokes. The pathophysiology is unknown. A deregulation of vasculogenic/angiogenic/inflammatory pathways has been hypothesized as a possible pathophysiological mechanism. Since lipids are implicated in modulating neo-vascularization/angiogenesis and inflammation, their deregulation is potentially involved in MA. Our aim is to evaluate angiogenic/vasculogenic/inflammatory proteins and lipid profile in plasma of MA patients and control subjects (healthy donors HD or subjects with atherosclerotic cerebrovascular disease ACVD). Angiogenic and inflammatory protein levels were measured by ELISA and a complete lipidomic analysis was performed on plasma by mass spectrometry. ELISA showed a significant decrease for MMP-9 released in plasma of MA. The untargeted lipidomic analysis showed a cumulative depletion of lipid asset in plasma of MA as compared to HD. Specifically, a decrease in membrane complex glycosphingolipids peripherally circulating in MA plasma with respect to HD was observed, likely suggestive of cerebral cellular recruitment. The quantitative targeted approach demonstrated an increase in free sphingoid bases, likely associated with a deregulated angiogenesis. Our findings indicate that lipid signature could play a central role in MA and that a detailed biomarker profile may contribute to untangle the complex, and still obscure, pathogenesis of MA.


Assuntos
Lipídeos/sangue , Doença de Moyamoya/sangue , Doenças Vasculares/sangue , Biomarcadores/sangue , Feminino , Humanos , Inflamação/sangue , Arteriosclerose Intracraniana/sangue , Lipidômica/métodos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/sangue
8.
Cell Physiol Biochem ; 54(1): 110-125, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31999897

RESUMO

BACKGROUND/AIMS: Cystic Fibrosis (CF) is an inherited disease associated with a variety of mutations affecting the CFTR gene. A deletion of phenylalanine 508 (F508) affects more than 70% of patients and results in unfolded proteins accumulation, originating a proteinopathy responsible for inflammation, impaired trafficking, altered metabolism, cholesterol and lipids accumulation, impaired autophagy at the cellular level. Lung inflammation has been extensively related to the accumulation of the lipotoxin ceramide. We recently proved that inhibition of ceramide synthesis by Myriocin reduces inflammation and ameliorates the defence response against pathogens infection, which is downregulated in CF. Here, we aim at demonstrating the mechanisms of Myriocin therapeutic effects in Cystic Fibrosis broncho-epithelial cells. METHODS: The effect of Myriocin treatment, on F508-CFTR bronchial epithelial cell line IB3-1 cells, was studied by evaluating the expression of key proteins and genes involved in autophagy and lipid metabolism, by western blotting and real time PCR. Moreover, the amount of glycerol-phospholipids, triglycerides, and cholesterols, sphingomyelins and ceramides were measured in treated and untreated cells by LC-MS. Finally, Sptlc1 was transiently silenced and the effect on ceramide content, autophagy and transcriptional activities was evaluated as above mentioned. RESULTS: We demonstrate that Myriocin tightly regulates metabolic function and cell resilience to stress. Myriocin moves a transcriptional program that activates TFEB, major lipid metabolism and autophagy regulator, and FOXOs, central lipid metabolism and anti-inflammatory/anti-oxidant regulators. The activity of these transcriptional factors is associated with the induction of PPARs nuclear receptors activity, whose targets are genes involved in lipid transport compartmentalization and oxidation. Transient silencing of SPTCL1 recapitulates the effects induced by Myriocin. CONCLUSION: Cystic Fibrosis bronchial epithelia accumulate lipids, exacerbating inflammation. Myriocin administration: i) activates the transcriptions of genes involved in enhancing autophagy-mediated stress clearance; ii) reduces the content of several lipid species and, at the same time, iii) enhances mitochondrial lipid oxidation. Silencing the expression of Sptlc1 reproduces Myriocin induced autophagy and transcriptional activities, demonstrating that the inhibition of sphingolipid synthesis drives a transcriptional program aimed at addressing cell metabolism towards lipid oxidation and at exploiting autophagy mediated clearance of stress. We speculate that regulating sphingolipid de novo synthesis can relieve from chronic inflammation, improving energy supply and anti-oxidant responses, indicating an innovative therapeutic strategy for CF.


Assuntos
Ácidos Graxos Monoinsaturados/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Esfingolipídeos/metabolismo , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Linhagem Celular , Colesterol/análise , Cromatografia Líquida de Alta Pressão , Fibrose Cística/metabolismo , Fibrose Cística/patologia , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Humanos , Espectrometria de Massas , PPAR gama/genética , PPAR gama/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Serina C-Palmitoiltransferase/antagonistas & inibidores , Serina C-Palmitoiltransferase/genética , Serina C-Palmitoiltransferase/metabolismo , Esfingolipídeos/análise , Esfingomielinas/análise
9.
J Transl Med ; 18(1): 481, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317546

RESUMO

BACKGROUND: In the past two decades, sphingolipids have become increasingly appreciated as bioactive molecules playing important roles in a wide array of pathophysiology mechanisms. Despite advances in the field, sphingolipids as nutrients remain little explored. Today the research is starting to move towards the study of the sphingomyelin content in human breast milk, recommended for feeding infants. METHODS: In the present study, we performed a lipidomic analysis in human breast milk in relation with maternal diet during pregnancy, in infant formulas, and in commercial whole and semi-skimmed milks for adults. Mediterranean, carnivorous and vegetarian diets were considered. RESULTS: The results showed that total sphingomyelin, ceramide and dihydroceramide species are independent on the diet. Interestingly, the milk sphingolipid composition is species-specific. In fact, infant formulas and commercial milks for adults have a lower level of total sphingomyelin and ceramide content than human breast milk with very different composition of each sphingolipid species. CONCLUSIONS: We conclude that human breast milk is a better source of sphingolipids than infant formulas for baby nutrition with potential implications for the brain development and cognitive functions.


Assuntos
Fórmulas Infantis , Leite , Adulto , Animais , Bovinos , Feminino , Humanos , Lactente , Recém-Nascido , Leite Humano , Gravidez , Esfingolipídeos
10.
Int J Mol Sci ; 21(6)2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32188137

RESUMO

UDP-glucose (UDP-Glc) is synthesized by UGP2-encoded UDP-Glc pyrophosphorylase (UGP) and is required for glycoconjugate biosynthesis and galactose metabolism because it is a uridyl donor for galactose-1-P (Gal1P) uridyltransferase. Chinese hamster lung fibroblasts harboring a hypomrphic UGP(G116D) variant display reduced UDP-Glc levels and cannot grow if galactose is the sole carbon source. Here, these cells were cultivated with glucose in either the absence or presence of galactose in order to investigate glycoconjugate biosynthesis and galactose metabolism. The UGP-deficient cells display < 5% control levels of UDP-Glc/UDP-Gal and > 100-fold reduction of [6-3H]galactose incorporation into UDP-[6-3H]galactose, as well as multiple deficits in glycoconjugate biosynthesis. Cultivation of these cells in the presence of galactose leads to partial restoration of UDP-Glc levels, galactose metabolism and glycoconjugate biosynthesis. The Vmax for recombinant human UGP(G116D) with Glc1P is 2000-fold less than that of the wild-type protein, and UGP(G116D) displayed a mildly elevated Km for Glc1P, but no activity of the mutant enzyme towards Gal1P was detectable. To conclude, although the mechanism behind UDP-Glc/Gal production in the UGP-deficient cells remains to be determined, the capacity of this cell line to change its glycosylation status as a function of extracellular galactose makes it a useful, reversible model with which to study different aspects of galactose metabolism and glycoconjugate biosynthesis.


Assuntos
Galactose/biossíntese , Glicoconjugados/biossíntese , UTP-Glucose-1-Fosfato Uridililtransferase/genética , Animais , Encefalopatias/metabolismo , Linhagem Celular , Defeitos Congênitos da Glicosilação/genética , Defeitos Congênitos da Glicosilação/metabolismo , Cricetinae , Meios de Cultura/química , Glicoesfingolipídeos , Glicosilação , Humanos , Cinética , Pulmão , UTP-Glucose-1-Fosfato Uridililtransferase/metabolismo , Uridina Difosfato Glucose/biossíntese
11.
J Neurochem ; 148(6): 698-711, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30269334

RESUMO

Until a few years ago, the majority of cell functions were envisioned as the result of protein and DNA activity. The cell membranes were considered as a mere structure of support and/or separation. In the last years, the function of cell membranes has, however, received more attention and their components of lipid nature have also been depicted as important cell mediators and the membrane organization was described as an important determinant for membrane-anchored proteins activity. In particular, because of their high diversity, glycosphingolipids offer a wide possibility of regulation. Specifically, the role of glycosphingolipids, in the fine-tuning of neuron activity, has recently received deep attention. For their pivotal role in vertebrate and mammals neural development, neural stem cells regulation is of main interest especially concerning their further functions in neurological pathology progression and treatment. Glycosphingolipids expression present a developmental regulation. In this view, glycosphingolipids can hold an important role in neural stem cells features because of their heterogeneity and their consequent capacity for eclectic interaction with other cell components.


Assuntos
Glicoesfingolipídeos/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Receptor Cross-Talk/fisiologia , Animais , Membrana Celular/metabolismo , Humanos
12.
Int J Mol Sci ; 20(18)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514293

RESUMO

BACKGROUND: Skull base chordomas are rare tumors arising from notochord. Sphingolipids analysis is a promising approach in molecular oncology, and it has never been applied in chordomas. Our aim is to investigate chordoma behavior and the role of ceramides. METHODS: Ceramides were extracted and evaluated by liquid chromatography and mass spectrometry in a cohort of patients with a skull base chordoma. Clinical data were also collected and correlated with ceramide levels. Linear regression and correlation analyses were conducted. RESULTS: Analyzing the association between ceramides level and MIB-1, total ceramides and dihydroceramides showed a strong association (r = 0.7257 and r = 0.6733, respectively) with MIB-1 staining (p = 0.0033 and p = 0.0083, respectively). Among the single ceramide species, Cer C24:1 (r = 0.8814, p ≤ 0.0001), DHCer C24:1 (r = 0.8429, p = 0.0002) and DHCer C18:0 (r = 0.9426, p ≤ 0.0001) showed a significant correlation with MIB-1. CONCLUSION: Our lipid analysis showed ceramides to be promising tumoral biomarkers in skull base chordomas. Long- and very-long-chain ceramides, such as Cer C24:1 and DHCer C24:1, may be related to a prolonged tumor survival and aggressiveness, and the understanding of their effective biological role will hopefully shed light on the mechanisms of chordoma radio-resistance, tendency to recur, and use of agents targeting ceramide metabolism.


Assuntos
Agressão , Ceramidas/metabolismo , Cordoma/metabolismo , Neoplasias da Base do Crânio/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células , Cordoma/diagnóstico por imagem , Feminino , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias da Base do Crânio/diagnóstico por imagem , Esfingolipídeos/metabolismo
13.
Biochim Biophys Acta ; 1860(6): 1089-97, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26922830

RESUMO

BACKGROUND: Fungal infections develop in pulmonary chronic inflammatory diseases such as asthma, Chronic Obstructive Pulmonary Disease (COPD) and Cystic Fibrosis (CF). The available antifungal drugs may fail to eradicate fungal pathogens, that can invade the lungs and vessels and spread by systemic circulation taking advantage of defective lung immunity. An increased rate of sphingolipid de novo synthesis, leading to ceramide accumulation, was demonstrated in CF and COPD inflamed lungs. The inhibitor of sphingolipid synthesis myriocin reduces inflammation and ameliorates the response against bacterial airway infection in CF mice. Myriocin also inhibits sphingolipid synthesis in fungi and exerts a powerful fungistatic effect. METHODS: We treated Aspergillus fumigatus infected airway epithelial cells with myriocin and we administered myriocin-loaded nanocarriers to A. fumigatus infected mice lung. RESULTS: We demonstrate here that de novo synthesized ceramide mediates the inflammatory response induced by A. fumigatus infection in airway epithelia. CF epithelial cells are chronically inflamed and defective in killing internalized conidia. Myriocin treatment reduced ceramide increase and inflammatory mediator release whereas it upregulated HO1 and NOD2, allowing the recovery of a functional killing of conidia in these cells. Myriocin-loaded nanocarriers, intratracheally administered to mice, significantly reduced both the inflammatory response induced by A. fumigatus pulmonary challenge and fungal lung invasion. CONCLUSIONS: We conclude that inhibition of sphingolipid synthesis can be envisaged as a dual anti-inflammatory and anti-fungal therapy in patients suffering from chronic lung inflammation with compromised immunity. GENERAL SIGNIFICANCE: Myriocin represents a powerful agent for inflammatory diseases and fungal infection.


Assuntos
Anti-Inflamatórios/farmacologia , Antifúngicos/farmacologia , Aspergillus fumigatus , Ceramidas/antagonistas & inibidores , Ácidos Graxos Monoinsaturados/farmacologia , Aspergilose Pulmonar/tratamento farmacológico , Animais , Antifúngicos/uso terapêutico , Linhagem Celular , Ceramidas/biossíntese , Ácidos Graxos Monoinsaturados/uso terapêutico , Humanos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Aspergilose Pulmonar/patologia
14.
Biomed Chromatogr ; 31(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28621883

RESUMO

Myriocin is a potent inhibitor of serine-palmitoyl-transferase, the first and rate-determining enzyme in the sphingolipids biosynthetic pathway. This study developed, validated and applied a LC-MS/MS method to measure myriocin in minute specimens of animal tissue. The chemical analog 14-OH-myriocin was used as the internal standard. The two molecules were extracted from the tissue homogenate by solid-phase extraction, separated by gradient reversed-phase liquid chromatography and measured by negative ion electrospray mass spectrometry in the triple quadrupole. Detection was accomplished by multiple reaction monitoring, employing the most representative transitions, 400@104 and 402@104 for myriocin and 14-OH-myriocin, respectively. The typical limit of detection and lower limit of quantitation of the optimized method were 0.9 pmol/mL (~0.016 pmol injected) and 2.3 pmol/mL, respectively, and the method was linear up to 250 pmol/mL range (r2 = 0.9996). The intra- and between-day repeatability afforded a coefficient of variation ≤7.0%. Applications included quantification of myriocin in mouse lungs after 24 h from administration of ~4 nmol by intra-tracheal delivery. Measured levels ranged from 4.11 (median; 2.3-7.4 IQR, n = 4) to 11.7 (median; 7.6-22.7 interquartile range (IQR), n = 6) pmol/lung depending on the different formulations used. Myriocin was also measured in retinas of mice treated by intravitreal injection and ranged from 0.045 (less than the limit of detection) to 0.35 pmol/retina.


Assuntos
Ácidos Graxos Monoinsaturados/análise , Ácidos Graxos Monoinsaturados/farmacocinética , Serina C-Palmitoiltransferase/antagonistas & inibidores , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia de Fase Reversa , Ácidos Graxos Monoinsaturados/química , Feminino , Limite de Detecção , Modelos Lineares , Pulmão/química , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reprodutibilidade dos Testes , Retina/química , Retina/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Distribuição Tecidual
15.
Molecules ; 22(7)2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28714922

RESUMO

In this work, we reported the application and validation of an improved high-performance liquid chromatography method coupled with a fluorimetric detector (HPLC-FL) to screen the activity of two heterocyclic derivatives reported as serine palmitoyl transferase (SPT) inhibitors. The analytical conditions were optimized in terms of the derivatization procedure, chromatographic condition, extraction procedure, and method validation according to EMEA guidelines. Once fully optimized, the method was applied to assess the SPT-inhibitory activity of the above-mentioned derivatives and of the reference inhibitor myriocin. The obtained results, expressed as a percentage of residual SPT activity, were compared to those obtained with the reference radio immune assay (RIA). The good correlation between the two types of assay demonstrated that the improved HPLC-FL method is suitable for a preliminary and rapid screening of potential SPT-inhibitors.


Assuntos
Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Fluorometria , Serina C-Palmitoiltransferase/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/normas , Relação Dose-Resposta a Droga , Fluorometria/métodos , Fluorometria/normas , Células HEK293 , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Reprodutibilidade dos Testes , Serina C-Palmitoiltransferase/química , Especificidade por Substrato
16.
Biol Chem ; 397(2): 147-55, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26501163

RESUMO

Gestation is regulated by an inflammatory process that allows implantation and parturition. The comprehension of such inflammatory switches is important for the identification of therapeutic targets in pregnancy defects. Sphingolipids are a class of structural membrane components with important signaling functions. Among sphingolipids, ceramide is a well-known mediator of stress signals and pro-inflammatory responses. In this paper, we evaluated the association between ceramide increase and the inflammatory process of labor, comparing placentas from vaginal deliveries, including both spontaneous and induced labor, versus elective cesarean. We demonstrated that: (i) the inflammatory marker IL-6 is upregulated in labored placentas; (ii) IL-6 content inversely correlates with labor duration; (iii) ceramide content and expression of serine palmitoyl transferase (SPT, rate limiting enzyme for de novo ceramide synthesis) are increased in labored placentas; (iv) the expression of SPT directly correlates with inflammation and inversely with labor duration. These observations suggest that ceramide metabolism and signaling may be implicated in controlling important inflammatory mechanisms driving gestation: we hypothesize that ceramide can be a therapeutic target in inflammatory complications of parturition.


Assuntos
Ceramidas/biossíntese , Inflamação/metabolismo , Trabalho de Parto/metabolismo , Adulto , Feminino , Humanos , Interleucina-6/metabolismo , Placenta/metabolismo , Placenta/patologia , Gravidez , Serina C-Palmitoiltransferase/biossíntese , Serina C-Palmitoiltransferase/metabolismo
17.
Biochim Biophys Acta ; 1840(1): 586-94, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24141140

RESUMO

BACKGROUND: Sphingolipids take part in immune response and can initiate and/or sustain inflammation. Various inflammatory diseases have been associated with increased ceramide content, and pharmacological reduction of ceramide diminishes inflammation damage in vivo. Inflammation and susceptibility to microbial infection are two elements in a vicious circle. Recently, sphingolipid metabolism inhibitors were used to reduce infection. Cystic fibrosis (CF) is characterized by a hyper-inflammation and an excessive innate immune response, which fails to evolve into adaptive immunity and to eradicate infection. Chronic infections result in lung damage and patient morbidity. Notably, ceramide content in mucosa airways is higher in CF mouse models and in patients than in control mice or healthy subjects. METHODS: The therapeutic potential of myriocin, an inhibitor of the sphingolipid de novo synthesis rate limiting enzyme (Serine Palmitoyl Transferase, SPT),was investigated in CF cells and mice models. RESULTS: We treated CF human respiratory epithelial cells with myriocin, This treatment resulted in reduced basal, as well as TNFα-stimulated, inflammation. In turn, TNFα induced an increase in SPT in these cells, linking de novo synthesis of ceramide to inflammation. Furthermore, myriocin-loaded nanocarrier, injected intratrachea prior to P. aeruginosa challenge, enabled a significant reduction of lung infection and reduced inflammation. CONCLUSIONS: The presented data suggest that de novo ceramide synthesis is constitutively enhanced in CF mucosa and that it can be envisaged as pharmacological target for modulating inflammation and restoring effective innate immunity against acute infection. GENERAL SIGNIFICANCE: Myriocin stands as a powerful immunomodulatory agent for inflammatory and infectious diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Antifúngicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Fibrose Cística/tratamento farmacológico , Ácidos Graxos Monoinsaturados/farmacologia , Nanopartículas/química , Esfingolipídeos/química , Animais , Anti-Inflamatórios/administração & dosagem , Antifúngicos/administração & dosagem , Western Blotting , Ceramidas/metabolismo , Cromatografia Líquida , Fibrose Cística/complicações , Fibrose Cística/imunologia , Portadores de Fármacos , Ensaio de Imunoadsorção Enzimática , Ácidos Graxos Monoinsaturados/administração & dosagem , Feminino , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos CFTR , Nanopartículas/administração & dosagem , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/etiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/etiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
Nutr Cancer ; 67(3): 494-503, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25705818

RESUMO

Natural dietary components are evolutionary-selected molecules able to control inflammation and cancerous transformation and progression. Because many studies assessed the beneficial properties of key molecules extracted from grapes, we aimed at investigating the properties of Liofenol™, a natural red wine lyophilized extract, devoid of alcohol and composed by a miscellaneous of components (polyphenols, flavonoids, anthocyanins). We proved that the colon cancer cell line HCT116 responded to Liofenol™ treatment by reducing their proliferation, in association with an increase of p53 and p21 cell cycle gate keepers. Liofenol™ increased dihydroceramides, sphingolipid mediators involved in cell cycle arrest and reduced proliferation rate. We observed a strong induction of antioxidant response, with the activation of the transcriptional factor Nrf2, involved in redox homeostasis and differentiation, without altering tumor sensitivity to chemotherapy. Liofenol™ induced an important morphology change in HCT116 cells, migration inhibition, undifferentiated stem/stem-like cells markers downregulation, and E-cadherin downregulation, interested in epithelia to mesenchymal malignant transition. We conclude that lyophilized grape extract, at dose comparable to putative dietary doses, can activate molecular pathways, involving Nrf2 signaling and the modulation of structural and signaling sphingolipid mediators that cooperate in promoting differentiation and reducing proliferation of digestive tract cancer cells.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Extratos Vegetais/farmacologia , Vitis , Antioxidantes/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/patologia , Inibidor de Quinase Dependente de Ciclina p21/análise , Células HCT116 , Humanos , Fator 2 Relacionado a NF-E2/genética , Esfingolipídeos/metabolismo , Proteína Supressora de Tumor p53/análise
19.
Mediators Inflamm ; 2015: 487508, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26770018

RESUMO

Sphingolipid bioactivities in the respiratory airways and the roles of the proteins that handle them have been extensively investigated. Gas or inhaled particles or microorganisms come into contact with mucus components, epithelial cells, blood barrier, and immune surveillance within the airways. Lung structure and functionality rely on a complex interplay of polar and hydrophobic structures forming the surfactant layer and governing external-internal exchanges, such as glycerol-phospholipids sphingolipids and proteins. Sphingolipids act as important signaling mediators involved in the control of cell survival and stress response, as well as secreted molecules endowed with inflammation-regulatory activities. Most successful respiratory infection and injuries evolve in the alveolar compartment, the critical lung functional unit involved in gas exchange. Sphingolipid altered metabolism in this compartment is closely related to inflammatory reaction and ceramide increase, in particular, favors the switch to pathological hyperinflammation. This short review explores a few mechanisms underlying sphingolipid involvement in the healthy lung (surfactant production and endothelial barrier maintenance) and in a selection of lung pathologies in which the impact of sphingolipid synthesis and metabolism is most apparent, such as acute lung injury, or chronic pathologies such as cystic fibrosis and chronic obstructive pulmonary disease.


Assuntos
Pneumonia/fisiopatologia , Esfingolipídeos/fisiologia , Animais , Fibrose Cística/fisiopatologia , Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , Humanos , Camundongos , Pneumonia/etiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia
20.
Eur J Neurosci ; 37(11): 1853-62, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23551187

RESUMO

The prevention of cone loss during retinal degeneration is a major goal of most therapeutic strategies in retinal degenerative diseases. An intriguing issue in the current research in this field is to understand why a genetic mutation that affects rods eventually leads to cone death. The main objective of the present study was to investigate to what extent rescuing rods from degeneration affects the survival of cones and prevents functional impairment of the visual performance. To this purpose, we compared rod and cone viabilities by both ex vivo and in vivo determinations in the rd10 mutant mouse, a validated model of human retinitis pigmentosa. The ex vivo experiments included morphological and biochemical tests, whereas in vivo studies compared the rod-mediated scotopic with the cone-mediated photopic electroretinogram. We also determined the overall visual performance by behaviorally testing the visual acuity (VA). The electroretinogram measurements showed that the kinetics of the photopic response in rd10 mice was slowed down with respect to the age-paired wild-type at a very early stage of the disease, when rods were still present and responsive. We then tested cone viability and function under a pharmacological scheme previously shown to prolong rod survival. The treatment consisted of eye drop administration of myriocin, an inhibitor of the biosynthesis of ceramide, a powerful proapoptotic messenger. The results of biochemical, morphological and functional assays converged to show that, in treated rd10 mice cone photoreceptors, the inner retina and overall visual performance were preserved well after rod death.


Assuntos
Células Fotorreceptoras Retinianas Cones/patologia , Retinose Pigmentar/fisiopatologia , Acuidade Visual , Animais , Apoptose , Sobrevivência Celular , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Ácidos Graxos Monoinsaturados/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Células Fotorreceptoras Retinianas Bastonetes/patologia , Retinose Pigmentar/tratamento farmacológico , Retinose Pigmentar/patologia
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