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1.
Int J Mol Sci ; 25(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38612700

RESUMO

Drug hypersensitivity reactions (DHRs) to platinum-based compounds (PCs) are on the rise, and their personalized and safe management is essential to enable first-line treatment for these cancer patients. This study aimed to evaluate the usefulness of the basophil activation test by flow cytometry (BAT-FC) and the newly developed sIgE-microarray and BAT-microarray in diagnosing IgE-mediated hypersensitivity reactions to PCs. A total of 24 patients with DHRs to PCs (20 oxaliplatin and four carboplatin) were evaluated: thirteen patients were diagnosed as allergic with positive skin tests (STs) or drug provocation tests (DPTs), six patients were diagnosed as non-allergic with negative STs and DPTs, and five patients were classified as suspected allergic because DPTs could not be performed. In addition, four carboplatin-tolerant patients were included as controls. The BAT-FC was positive in 2 of 13 allergic patients, with a sensitivity of 15.4% and specificity of 100%. However, the sIgE- and BAT-microarray were positive in 11 of 13 DHR patients, giving a sensitivity of over 84.6% and a specificity of 90%. Except for one patient, all samples from the non-allergic and control groups were negative for sIgE- and BAT-microarray. Our experience indicated that the sIgE- and BAT-microarray could be helpful in the endophenotyping of IgE-mediated hypersensitivity reactions to PCs and may provide an advance in decision making for drug provocation testing.


Assuntos
Hipersensibilidade a Drogas , Hipersensibilidade Imediata , Poliquetos , Radiossensibilizantes , Tionas , Humanos , Animais , Teste de Degranulação de Basófilos , Compostos de Platina , Carboplatina/efeitos adversos , Hipersensibilidade a Drogas/diagnóstico , Antineoplásicos Alquilantes , Imunoglobulina E
2.
Int J Mol Sci ; 24(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37511302

RESUMO

In the first wave of COVID-19, up to 20% of patients had skin lesions with variable characteristics. There is no clear evidence of the involvement of the SARS-CoV-2 virus in all cases; some of these lesions may be secondary to drug hypersensitivity. To analyze the possible cause of the skin lesions, we performed a complete allergology study on 11 patients. One year after recovery from COVID-19, we performed a lymphocyte transformation test (LTT) and Th1/Th2 cytokine secretion assays for PBMCs. We included five nonallergic patients treated with the same drugs without lesions. Except for one patient who had an immediate reaction to azithromycin, all patients had a positive LTT result for at least one of the drugs tested (azithromycin, clavulanic acid, hydroxychloroquine, lopinavir, and ritonavir). None of the nonallergic patients had a positive LTT result. We found mixed Th1/Th2 cytokine secretion (IL-4, IL-5, IL-13, and IFN-γ) in patients with skin lesions corresponding to mixed drug hypersensitivity type IVa and IVb. In all cases, we identified a candidate drug as the culprit for skin lesions during SARS-CoV-2 infection, although only three patients had a positive drug challenge. Therefore, it would be reasonable to recommend avoiding the drug in question in all cases.


Assuntos
COVID-19 , Hipersensibilidade a Drogas , Humanos , Azitromicina/efeitos adversos , Ativação Linfocitária , SARS-CoV-2 , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/etiologia , Citocinas , Teste para COVID-19
3.
Semin Cancer Biol ; 73: 101-115, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32931953

RESUMO

Selective estrogen receptor modulators (SERMs) are a class of compounds that bind to estrogen receptors (ERs) and possess estrogen agonist or antagonist actions in different tissues. As such, they are widely used drugs. For instance, tamoxifen, the most prescribed SERM, is used to treat ERα-positive breast cancer. Aside from their therapeutic targets, SERMs have the capacity to broadly affect cellular cholesterol metabolism and handling, mainly through ER-independent mechanisms. Cholesterol metabolism reprogramming is crucial to meet the needs of cancer cells, and different key processes involved in cholesterol homeostasis have been associated with cancer progression. Therefore, the effects of SERMs on cholesterol homeostasis may be relevant to carcinogenesis, either by contributing to the anticancer efficacy of these compounds or, conversely, by promoting resistance to treatment. Understanding these aspects of SERMs actions could help to design more efficacious therapies. Herein we review the effects of SERMs on cellular cholesterol metabolism and handling and discuss their potential in anticancer pharmacology.


Assuntos
Colesterol/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Neoplasias , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Animais , Humanos , Metabolismo dos Lipídeos/fisiologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
4.
Cardiovasc Diabetol ; 20(1): 72, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33766036

RESUMO

BACKGROUND: Peripheral artery disease (PAD) is recognized as a significant predictor of mortality and adverse cardiovascular outcomes in patients with coronary heart disease (CHD). In fact, coexisting PAD and CHD is strongly associated with a greater coronary event recurrence compared with either one of them alone. High-density lipoprotein (HDL)-mediated cholesterol efflux capacity (CEC) is found to be inversely associated with an increased risk of incident CHD. However, this association is not established in patients with PAD in the context of secondary prevention. In this sense, our main aim was to evaluate the association between CEC and PAD in patients with CHD and whether the concurrent presence of PAD and T2DM influences this association. METHODS: CHD patients (n = 1002) from the CORDIOPREV study were classified according to the presence or absence of PAD (ankle-brachial index, ABI ≤ 0.9 and ABI > 0.9 and < 1.4, respectively) and T2DM status. CEC was quantified by incubation of cholesterol-loaded THP-1 cells with the participants' apoB-depleted plasma was performed. RESULTS: The presence of PAD determined low CEC in non-T2DM and newly-diagnosed T2DM patients. Coexisting PAD and newly-diagnosed T2DM provided and additive effect providing an impaired CEC compared to non-T2DM patients with PAD. In established T2DM patients, the presence of PAD did not determine differences in CEC, compared to those without PAD, which may be restored by glucose-lowering treatment. CONCLUSIONS: Our findings suggest an inverse relationship between CEC and PAD in CHD patients. These results support the importance of identifying underlying mechanisms of PAD, in the context of secondary prevention, that provide potential therapeutic targets, that is the case of CEC, and establishing strategies to prevent or reduce the high risk of cardiovascular events of these patients. Trial registration https://clinicaltrials.gov/ct2/show/NCT00924937 . Unique Identifier: NCT00924937.


Assuntos
Colesterol/sangue , Doença das Coronárias/sangue , Diabetes Mellitus Tipo 2/sangue , Macrófagos/metabolismo , Doença Arterial Periférica/sangue , Adulto , Idoso , Apolipoproteína B-100/sangue , Biomarcadores/sangue , Doença das Coronárias/diagnóstico , Doença das Coronárias/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Espanha/epidemiologia , Células THP-1 , Adulto Jovem
5.
Int J Mol Sci ; 22(8)2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33920193

RESUMO

Atypical or second-generation antipsychotics are used in the treatment of psychosis and behavioral problems in older persons with dementia. However, these pharmaceutical drugs are associated with an increased risk of stroke in such patients. In this study, we evaluated the effects of risperidone treatment on phospholipid and sphingolipid composition and lipid raft function in peripheral blood mononuclear cells (PBMCs) of older patients (mean age >88 years). The results showed that the levels of dihydroceramides, very-long-chain ceramides, and lysophosphatidylcholines decreased in PBMCs of the risperidone-treated group compared with untreated controls. These findings were confirmed by in vitro assays using human THP-1 monocytes. The reduction in the levels of very-long-chain ceramides and dihydroceramides could be due to the decrease in the expression of fatty acid elongase 3, as observed in THP-1 monocytes. Moreover, risperidone disrupted lipid raft domains in the plasma membrane of PBMCs. These results indicated that risperidone alters phospholipid and sphingolipid composition and lipid raft domains in PBMCs of older patients, potentially affecting multiple signaling pathways associated with these membrane domains.


Assuntos
Ceramidas/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Transtornos Psicóticos/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antipsicóticos/farmacologia , Membrana Celular/genética , Membrana Celular/metabolismo , Feminino , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Metabolismo dos Lipídeos/genética , Lisofosfolipídeos/genética , Masculino , Olanzapina/farmacologia , Transtornos Psicóticos/sangue , Transtornos Psicóticos/patologia , Risperidona/farmacologia , Esfingolipídeos/genética
6.
Pediatr Allergy Immunol ; 31(2): 175-185, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31655013

RESUMO

BACKGROUND: Peptide microarray technology has been proposed as a useful tool for diagnosing food allergy. However, there is considerable heterogeneity in the clinical methods and analytical procedures used to assess its diagnostic and prognostic performance. We performed a systematic review of studies that have used B-cell epitopes by peptide microarray in food allergies to identify the clinical utility of this immunologic technique. METHODS: Studies were screened in PubMed, Web of Science, and Embase according to an established keyword algorithm. Data extraction was performed, and information was collected in an Excel database. Descriptive analysis was carried out using Stata software. RESULTS: Thirty relevant studies were identified. Most articles were cross-sectional (n = 24), included epitope mapping (n = 9), and assessed diagnostic utility (n = 11). All studies recruited allergic patients, and some included additional patients (sensitized, persistent, and tolerant). The primary microarray variables studied were IgE intensity (n = 29), IgG4 intensity (n = 15), and number of peptides (n = 17). Statistical approaches differed significantly between studies, with the Wilcoxon test being the most frequently used (n = 10). CONCLUSIONS: Sensitization to particular epitopes of milk, peanut, and shrimp allergens can be used to determine clinical reactivity, persistence, severity, or response to oral immunotherapy; however, important methodological questions need to be addressed before drawing definitive conclusions. More research is needed to address the accuracy and clinical benefits of microarray-based technology. Standards are required to improve consistency and reproducibility, and to allow for better understanding of research findings.


Assuntos
Alérgenos/genética , Mapeamento de Epitopos/métodos , Epitopos de Linfócito B/genética , Hipersensibilidade Alimentar/diagnóstico , Peptídeos/genética , Alérgenos/imunologia , Animais , Epitopos de Linfócito B/imunologia , Alimentos , Humanos , Análise em Microsséries , Peptídeos/imunologia , Reprodutibilidade dos Testes
8.
Biochim Biophys Acta ; 1851(9): 1240-53, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26055626

RESUMO

The mevalonate pathway is tightly linked to cell division. Mevalonate derived non-sterol isoprenoids and cholesterol are essential for cell cycle progression and mitosis completion respectively. In the present work, we studied the effects of fluoromevalonate, a competitive inhibitor of mevalonate diphosphate decarboxylase, on cell proliferation and cell cycle progression in both HL-60 and MOLT-4 cells. This enzyme catalyzes the synthesis of isopentenyl diphosphate, the first isoprenoid in the cholesterol biosynthesis pathway, consuming ATP at the same time. Inhibition of mevalonate diphosphate decarboxylase was followed by a rapid accumulation of mevalonate diphosphate and the reduction of ATP concentrations, while the cell content of cholesterol was barely affected. Strikingly, mevalonate diphosphate decarboxylase inhibition also resulted in the depletion of dNTP pools, which has never been reported before. These effects were accompanied by inhibition of cell proliferation and cell cycle arrest at S phase, together with the appearance of γ-H2AX foci and Chk1 activation. Inhibition of Chk1 in cells treated with fluoromevalonate resulted in premature entry into mitosis and massive cell death, indicating that the inhibition of mevalonate diphosphate decarboxylase triggered a DNA damage response. Notably, the supply of exogenously deoxyribonucleosides abolished γ-H2AX formation and prevented the effects of mevalonate diphosphate decarboxylase inhibition on DNA replication and cell growth. The results indicate that dNTP pool depletion caused by mevalonate diphosphate decarboxylase inhibition hampered DNA replication with subsequent DNA damage, which may have important consequences for replication stress and genomic instability.


Assuntos
Carboxiliases/metabolismo , Desoxirribonucleosídeos/metabolismo , Linfócitos/efeitos dos fármacos , Ácido Mevalônico/farmacologia , Trifosfato de Adenosina/metabolismo , Carboxiliases/antagonistas & inibidores , Carboxiliases/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 1 do Ponto de Checagem , Dano ao DNA , Replicação do DNA/efeitos dos fármacos , Desoxirribonucleosídeos/farmacologia , Regulação da Expressão Gênica , Células HL-60 , Halogenação , Hemiterpenos/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Linfócitos/citologia , Linfócitos/metabolismo , Ácido Mevalônico/análogos & derivados , Ácido Mevalônico/metabolismo , Compostos Organofosforados/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais
10.
J Bone Miner Metab ; 34(6): 655-661, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26438320

RESUMO

Metabolic bone disease may appear as a complication of obesity surgery. Because an imbalance in the osteoprotegerin and receptor-activator of nuclear factor-κB ligand system may underlie osteoporosis, we aimed to study this system in humans in the metabolic bone disease occurring after obesity surgery. In this study we included sixty women with a mean age of 47 ± 10 years studied 7 ± 2 years after bariatric surgery. The variables studied were bone mineral density, ß-isomer of C-terminal telopeptide of type I collagen cross-links (a bone resorption marker), the bone formation markers osteocalcin and N-terminal propeptide of procollagen 1, serum osteoprotegerin and receptor-activator of nuclear factor-κB ligand. Serum osteoprotegerin inversely correlated with the bone remodeling markers osteocalcin, ß-isomer of C-terminal telopeptide of type I collagen cross-links and N-terminal propeptide of procollagen 1. The osteoprotegerin and receptor-activator of nuclear factor-κB ligand ratio also correlated inversely with serum parathormone and osteocalcin. Bone mineral density at the lumbar spine was associated with age (ß = -0.235, P = 0.046), percentage of weight loss (ß = 0.421, P = 0.001) and osteoprotegerin and receptor-activator of nuclear factor-κB ligand ratio (ß = 0.259, P = 0.029) in stepwise multivariate analysis (R 2 = 0.29, F = 7.49, P < 0.001). Bone mineral density at the hip site was associated only with percentage of weight loss (ß = 0.464, P < 0.001) in stepwise multivariate regression (R 2 = 0.21, F = 15.1, P < 0.001). These data show that the osteoprotegerin and receptor-activator of nuclear factor-κB ligand system is associated with bone markers and bone mineral density at the lumbar spine after obesity surgery.


Assuntos
Cirurgia Bariátrica/efeitos adversos , Densidade Óssea , Doenças Ósseas Metabólicas , Obesidade , Osteoprotegerina/sangue , Complicações Pós-Operatórias/sangue , Ligante RANK/sangue , Adulto , Idoso , Biomarcadores/sangue , Doenças Ósseas Metabólicas/sangue , Doenças Ósseas Metabólicas/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/cirurgia , Osteocalcina/sangue , Hormônio Paratireóideo/sangue , Ossos Pélvicos/metabolismo , Coluna Vertebral/metabolismo
11.
Arthroscopy ; 30(9): 1131-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24951133

RESUMO

PURPOSE: To define the variations in the expression of 5 growth factor genes in meniscal tissue after a lesion is created in the avascular zone of the medial meniscus of the rabbit. METHODS: A longitudinal lesion was created in the avascular zone of the anterior horn of the medial meniscus in 42 rabbits. Six animals were killed at 0, 1, 3, 7, 14, 21, and 120 days after lesion creation. Meniscal tissue from the avascular and vascular zones was harvested. A quantitative polymerase chain reaction analysis was performed to evaluate the expression levels of 5 different growth factors: vascular endothelial growth factor A (VEGF-A), insulin-like growth factor 1 (IGF-1), transforming growth factor ß1 (TGF-ß1), platelet-derived growth factor ß (PDGF-ß), and interleukin 1ß. RESULTS: The basal expression levels of all the growth factors studied were similar in the avascular and vascular zones. There was an increase in VEGF-A expression in the avascular zone on the 14th day, an increase in IGF-1 expression in the vascular zone on the 14th day, a decrease in PDGF-ß expression in both zones in the first week, an increase in interleukin 1ß expression in both zones on the first day, and a decrease in TGF-ß1 expression in the vascular zone in the first week. At 120 days, the expression levels of all 5 growth factors returned to basal levels. CONCLUSIONS: There are significant variations in the expression of the growth factors studied during the first weeks after meniscal lesion creation. The preinjury expression levels are similar in the avascular and vascular zones and are not significantly different from the basal levels 4 months after injury. CLINICAL RELEVANCE: This study identifies potential therapeutic molecular targets (VEGF-A, IGF-1, TGF-ß1, and PDGF-ß) that can be used in the treatment of meniscal tears.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Meniscos Tibiais/metabolismo , Lesões do Menisco Tibial , Animais , Fator de Crescimento Insulin-Like I/metabolismo , Traumatismos do Joelho , Fator de Crescimento Derivado de Plaquetas/metabolismo , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-sis/metabolismo , Coelhos , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização
12.
Surg Laparosc Endosc Percutan Tech ; 34(1): 1-8, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37963307

RESUMO

BACKGROUND: High CO 2 pneumoperitoneum pressure during laparoscopy adversely affects the peritoneal environment. This study hypothesized that low pneumoperitoneum pressure may be linked to less peritoneal damage and possibly to better clinical outcomes. MATERIALS AND METHODS: One hundred patients undergoing scheduled laparoscopic cholecystectomy were randomized 1:1 to low or to standard pneumoperitoneum pressure. Peritoneal biopsies were performed at baseline time and 1 hour after peritoneum insufflation in all patients. The primary outcome was peritoneal remodeling biomarkers and apoptotic index. Secondary outcomes included biomarker differences at the studied times and some clinical variables such as length of hospital stay, and quality and safety issues related to the procedure. RESULTS: Peritoneal IL6 after 1 hour of surgery was significantly higher in the standard than in the low-pressure group (4.26±1.34 vs. 3.24±1.21; P =0.001). On the contrary, levels of connective tissue growth factor and plasminogen activator inhibitor-I were higher in the low-pressure group (0.89±0.61 vs. 0.61±0.84; P =0.025, and 0.74±0.89 vs. 0.24±1.15; P =0.028, respectively). Regarding apoptotic index, similar levels were found in both groups and were 44.0±10.9 and 42.5±17.8 in low and standard pressure groups, respectively. None of the secondary outcomes showed differences between the 2 groups. CONCLUSIONS: Peritoneal inflammation after laparoscopic cholecystectomy is higher when surgery is performed under standard pressure. Adhesion formation seems to be less in this group. The majority of patients undergoing surgery under low pressure were operated under optimal workspace conditions, regardless of the surgeon's expertise.


Assuntos
Colecistectomia Laparoscópica , Insuflação , Laparoscopia , Pneumoperitônio , Humanos , Peritônio/cirurgia , Colecistectomia Laparoscópica/efeitos adversos , Colecistectomia Laparoscópica/métodos , Pneumoperitônio/etiologia , Insuflação/efeitos adversos , Insuflação/métodos , Laparoscopia/métodos , Pneumoperitônio Artificial/efeitos adversos , Pneumoperitônio Artificial/métodos
13.
Int Arch Allergy Immunol ; 161(1): 11-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23257567

RESUMO

BACKGROUND: Ovomucoid (Gal d 1) has been demonstrated to be the most important allergen in IgE-mediated egg allergy. Peptide microarray analysis is a novel method that can provide useful information on the nature of specific allergens. METHODS: A peptide microarray immunoassay was performed using a 15- and 20-amino acid (aa) library of overlapping peptides (3-offset) of the primary sequence of ovomucoid. Sera from 50 patients with IgE-mediated egg allergy and reactivity to ovomucoid, with more than 1 year of follow-up, and sera from 10 controls were tested. Peptides were considered major epitopes when the average weighted Z-score was greater than 3 and recognized by at least 20% of the patient's sera. Specific IgE epitopes were established on the basis of the IgE/IgG4 Z-score ratio. RESULTS: The IgE and IgG4 recognition pattern was similar in both sets of peptides, but the signal intensity was generally higher in the 20-aa set. Thirty-four percent of the patients did not recognize any IgE sequential peptide and 20% of the patients recognized more than 10 sequential peptides. We identified 3 major IgE B-cell epitopes in domains I and II of ovomucoid. IgE/IgG4 ratio analysis showed that peptides 1-2 (aa 4-20) and peptides 29-31 (aa 91-104) were specific IgE epitopes. CONCLUSION: By using peptide microarray immunoassay in egg-allergic patients, we established that 34% of the patients do not have any linear epitope recognized by IgE. Further studies are needed to determine the clinical relevance of this finding.


Assuntos
Hipersensibilidade a Ovo/imunologia , Epitopos/imunologia , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Ovomucina/imunologia , Adolescente , Criança , Pré-Escolar , Hipersensibilidade a Ovo/sangue , Mapeamento de Epitopos/métodos , Epitopos/química , Feminino , Humanos , Imunoglobulina E/química , Imunoglobulina G/química , Masculino , Ovomucina/química , Análise Serial de Proteínas/métodos
14.
Methods Mol Biol ; 2578: 219-236, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152291

RESUMO

Peptide microarrays are a powerful tool to identify linear epitopes of food allergens in a high-throughput manner. The main advantages of the microarray-based immunoassay are as follows: the possibility to assay thousands of targets simultaneously, the requirement of a low volume of serum, the more robust statistical analysis, and the possibility to test simultaneously several immunoglobulin subclasses. Among them, the last one has a special interest in the field of food allergy, because the development of tolerance to food allergens has been associated with a decrease in IgE and an increase in IgG4 levels against linear epitopes. However, the main limitation to the clinical use of microarray is the automated analysis of the data. Recent studies mapping the linear epitopes of food allergens with peptide microarray immunoassays have identified peptide biomarkers that can be used for early diagnosis of food allergies and to predict their severity or the self-development of tolerance. Using this approach, we have worked on epitope mapping of the two most important food allergens in the Spanish population, cow's milk, and chicken eggs. The final aim of these studies is to define subsets of peptides that could be used as biomarkers to improve the diagnosis and prognosis of food allergies. This chapter describes the protocol to produce microarrays using a library of overlapping peptides corresponding to the primary sequences of food allergens and data acquisition and analysis of IgE and IgG4 binding epitopes.


Assuntos
Hipersensibilidade Alimentar , Imunoglobulina G , Alérgenos , Animais , Biomarcadores , Bovinos , Mapeamento de Epitopos/métodos , Epitopos , Feminino , Hipersensibilidade Alimentar/diagnóstico , Imunoensaio/métodos , Imunoglobulina E/metabolismo , Peptídeos
15.
Artigo em Inglês | MEDLINE | ID: mdl-37059386

RESUMO

Dihydrosphingolipids are lipids biosynthetically related to ceramides. An increase in ceramides is associated with enhanced fat storage in the liver, and inhibition of their synthesis is reported to prevent the appearance of steatosis in animal models. However, the precise association of dihydrosphingolipids with non-alcoholic fatty liver disease (NAFLD) is yet to be established. We employed a diet induced NAFLD mouse model to study the association between this class of compounds and disease progression. Mice fed a high-fat diet were sacrificed at 22, 30 and 40 weeks to reproduce the full spectrum of histological damage found in human disease, steatosis (NAFL) and steatohepatitis (NASH) with and without significant fibrosis. Blood and liver tissue samples were obtained from patients whose NAFLD severity was assessed histologically. To demonstrate the effect of dihydroceramides over NAFLD progression we treated mice with fenretinide an inhibitor of dihydroceramide desaturase-1 (DEGS1). Lipidomic analyses were performed using liquid chromatography-tandem mass spectrometry. Triglycerides, cholesteryl esters and dihydrosphingolipids were increased in the liver of model mice in association with the degree of steatosis and fibrosis. Dihydroceramides increased with the histological severity observed in liver samples of mice (0.024 ± 0.003 nmol/mg vs 0.049 ± 0.005 nmol/mg, non-NAFLD vs NASH-fibrosis, p < 0.0001) and patients (0.105 ± 0.011 nmol/mg vs 0.165 ± 0.021 nmol/mg, p = 0.0221). Inhibition of DEGS1 induce a four-fold increase in dihydroceramides improving steatosis but increasing the inflammatory activity and fibrosis. In conclusion, the degree of histological damage in NAFLD correlate with dihydroceramide and dihydrosphingolipid accumulation. LAY SUMMARY: Accumulation of triglyceride and cholesteryl ester lipids is the hallmark of non-alcoholic fatty liver disease. Using lipidomics, we examined the role of dihydrosphingolipids in NAFLD progression. Our results demonstrate that de novo dihydrosphingolipid synthesis is an early event in NAFLD and the concentrations of these lipids are correlated with histological severity in both mouse and human disease.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Animais , Camundongos , Hepatopatia Gordurosa não Alcoólica/patologia , Fibrose , Triglicerídeos , Ceramidas
16.
Antimicrob Agents Chemother ; 56(5): 2763-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22330911

RESUMO

The recent increase of CTX-M-15-producing Escherichia coli isolates in our institution was caused by diverse clonal backgrounds, including mainly B2 sequence type 131 (ST131) clones presenting variable virulence profiles but also A(1) (ST617, ST410), B1, and D(1) (ST405) clones. Besides IncFII-pC15-1a, we detected multidrug-resistant IncA/C(2) and IncN plasmids carrying bla(CTX-M-15) and/or qnrS1. Our study highlights the diversification of highly transmissible resistant and virulent clones and the recombinogenic potential of broad-host plasmids contributing to the expansion of genetic regions coding for multidrug resistance to other bacterial lineages.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/genética , Plasmídeos/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Células Clonais , Farmacorresistência Bacteriana Múltipla/genética , Eletroforese em Gel de Campo Pulsado , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Infecções por Escherichia coli/microbiologia , Transferência Genética Horizontal , Especificidade de Hospedeiro , Humanos , Filogenia , Recombinação Genética , Espanha
17.
Oncol Lett ; 24(3): 295, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35949615

RESUMO

Previous studies have shown that intermittent exposure to a 50 Hz, 100 µT sinusoidal magnetic field (MF) promotes proliferation of human neuroblastoma cells, NB69. This effect is mediated by activation of the epidermal growth factor receptor through a free radical-dependent activation of the p38 pathway. The present study investigated the possibility that the oxidative stress-sensitive protein p53 is a potential target of the MF, and that field exposure can affect the protein expression. To that end, NB69 cells were exposed to short intervals of 30 to 120 min to the aforementioned MF parameters. Two specific anti-p53 antibodies that allow discrimination between the wild and unfolded forms of p53 were used to study the expression and cellular distribution of both isoforms of the protein. The expression of the antiapoptotic protein Bcl-2, whose regulation is mediated by p53, was also analyzed. The obtained results revealed that MF exposure induced increases in p53 gene expression and in protein expression of the wild-type form of p53. Field exposure also caused overexpression of the unfolded form of p53, together with changes in the nuclear/cytoplasmic distribution of both forms of the protein. The expression of protein Bcl-2 was also significantly increased in response to the MF. As a whole, these results indicated that the MF is capable of interacting with the function, distribution and conformation of protein p53. Such interactions could be involved in previously reported MF effects on NB69 proliferation promotion.

18.
Biochem Pharmacol ; 196: 114623, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34052188

RESUMO

The mevalonate pathway is responsible for the synthesis of isoprenoids, including sterols and other metabolites that are essential for diverse biological functions. Cholesterol, the main sterol in mammals, and non-sterol isoprenoids are in high demand by rapidly dividing cells. As evidence of its importance, many cell signaling pathways converge on the mevalonate pathway and these include those involved in proliferation, tumor-promotion, and tumor-suppression. As well as being a fundamental building block of cell membranes, cholesterol plays a key role in maintaining their lipid organization and biophysical properties, and it is crucial for the function of proteins located in the plasma membrane. Importantly, cholesterol and other mevalonate derivatives are essential for cell cycle progression, and their deficiency blocks different steps in the cycle. Furthermore, the accumulation of non-isoprenoid mevalonate derivatives can cause DNA replication stress. Identification of the mechanisms underlying the effects of cholesterol and other mevalonate derivatives on cell cycle progression may be useful in the search for new inhibitors, or the repurposing of preexisting cholesterol biosynthesis inhibitors to target cancer cell division. In this review, we discuss the dependence of cell division on an active mevalonate pathway and the role of different mevalonate derivatives in cell cycle progression.


Assuntos
Ciclo Celular/fisiologia , Colesterol/metabolismo , Ácido Mevalônico/metabolismo , Esteróis/metabolismo , Terpenos/metabolismo , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
19.
Biomedicines ; 10(6)2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35740338

RESUMO

Exosomes/microvesicles originate from multivesicular bodies that allow the secretion of endolysosome components out of the cell. In the present work, we investigated the effects of rottlerin, a polyphenol, on exosome/microvesicle secretion in a model of intracellular lipid trafficking impairment, and elucidated the mechanism of action. In a model of lipid trafficking impairment in C6 glia cells, rottlerin increased ceramide levels, while decreasing hexosylceramide content. This was accompanied by increased exosome/microvesicle secretion, thereby reducing the concentration of lipids in the endolysosomal compartment. The reduction of hexosylceramide levels by rottlerin was attributed to the increase of ß-glucosidase (glucosylceramidase) activity, and the effects of rottlerin were abrogated by ß-glucosidase inhibitors such as isofagomine D-tartrate and AMP-deoxynojirimycin. Moreover, treatment with ML-266, a potent activator of the ß-glucosidase enzyme, recapitulated the effects of rottlerin on the sphingolipid profile and exosome/microvesicle secretion. Finally, inhibition of AMPK (AMP-activated protein kinase) using compound C prevented both exosome/microvesicle secretion and the elimination of endolysosome lipids, which were promoted by rottlerin. The results showed that the decrease in intracellular lipid deposition induced by rottlerin was mediated by ß-glucosidase activation and exosome/microvesicle release via the AMPK pathway. Rottlerin consumption could represent an additional health benefit in lysosomal deposition diseases.

20.
Methods Mol Biol ; 2344: 107-117, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34115355

RESUMO

Food allergy is becoming a great problem in industrialized countries. Thus, there is the need for a robust understanding of all aspects characterizing IgE response to allergens. The epitope mapping of B-cell epitopes has the potential to become a fundamental tool for food allergy diagnosis and prognosis and to lead to a better understanding of the pathogenesis. Using this approach, we have worked on epitope mapping of the most important plant food allergens identified in the Mediterranean area. The final aim of this study is to define the immune response regarding B epitopes and its clinical relevance in LTP allergy. This chapter describes the protocol to produce microarrays using a library of overlapping peptides corresponding to the primary sequences of allergenic lipid transfer proteins.


Assuntos
Proteínas de Transporte/imunologia , Mapeamento de Epitopos , Hipersensibilidade Alimentar/imunologia , Análise Serial de Proteínas , Humanos
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