Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Arq. bras. cardiol ; Arq. bras. cardiol;120(11): e20230078, 2023. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1520143

RESUMO

Resumo Fundamento Embora os ácidos graxos poli-insaturados ômega-3 e ômega-6 (AGPIs n-3 e n-6) tenham efeitos bem conhecidos sobre os fatores de risco de doenças cardiovasculares (DCV), ainda existe um conhecimento limitado sobre como eles afetam os indicadores de qualidade da LDL. Objetivo Avaliar as associações dos AGPIs n-3 e n-6 de hemácias com o tamanho da partícula da LDL, LDL-c pequena e densa (sdLDL-c) e com LDL eletronegativa [LDL(-)] em adultos com fatores de risco para DCV. Métodos Estudo transversal com 335 homens e mulheres de 30 a 74 anos com, pelo menos, um fator de risco cardiovascular. Foram realizadas análises de parâmetros bioquímicos, como glicose, insulina, HbA1c, proteína C reativa (PCR), perfil lipídico, subfrações de lipoproteínas, partícula eletronegativa de LDL [LDL(-)] e seu autoanticorpo, e os AGPIs n-3 e n- 6 de hemácias. Os testes t independente/teste de Mann-Whitney, ANOVA unidirecional/teste de Kruskal-Wallis e regressões lineares múltiplas foram aplicados. Todos os testes foram bilaterais e um valor de p inferior a 0,05 foi considerado estatisticamente significativo. Resultados A relação n-6/n-3 de hemácias foi associada ao aumento dos níveis de LDL(-) (β = 4,064; IC de 95% = 1,381 - 6,748) e sdLDL-c (β = 1,905; IC de 95% = 0,863 - 2,947), e redução do tamanho das partículas de LDL (β = -1,032; IC de 95% = -1,585 − -0,478). Individualmente, os AGPIs n-6 e n-3 apresentaram associações opostas com esses parâmetros, realçando os efeitos protetores do n-3 e evidenciando os possíveis efeitos adversos do n-6 na qualidade das partículas de LDL. Conclusão O AGPI n-6, presente nas hemácias, foi associado ao aumento do risco cardiometabólico e à aterogenicidade das partículas de LDL, enquanto o AGPI n-3 foi associado a melhores parâmetros cardiometabólicos e à qualidade das partículas de LDL.


Abstract Background While Omega-3 and omega-6 polyunsaturated fatty acids (n-3 and n-6 PUFAs) have established effects on cardiovascular disease (CVD) risk factors, little is known about their impacts on LDL quality markers. Objective To assess the associations of n-3 and n-6 PUFA within red blood cells (RBC) with LDL particle size, small dense LDL-c (sdLDL-c), and electronegative LDL [LDL(-)] in adults with CVD risk factors. Methods Cross-sectional study involving 335 men and women aged 30 to 74 with at least one cardiovascular risk factor. Analyses were conducted on biochemical parameters, such as glucose, insulin, HbA1c, C-reactive protein (CRP), lipid profile, lipoprotein subfractions, electronegative LDL particle [LDL(-)] and its autoantibody, and RBC n-3 and n-6 PUFAs. Independent t-test/Mann-Whitney test, one-way ANOVA/Kruskal-Wallis test, and multiple linear regressions were applied. All tests were two-sided, and a p-value of less than 0.05 was considered statistically significant. Results The RBC n-6/n-3 ratio was associated with increased LDL(-) (β = 4.064; 95% CI = 1.381 - 6.748) and sdLDL-c (β = 1.905; 95% CI = 0.863 - 2.947) levels, and reduced LDL particle size (β = -1.032; 95% CI = -1.585 − -0.478). Separately, n-6 and n-3 PUFAs had opposing associations with those parameters, reinforcing the protective effects of n-3 and showing the potential negative effects of n-6 on LDL particle quality. Conclusion RBC n-6 PUFA was associated with increased cardiometabolic risk and atherogenicity of LDL particles, while n-3 PUFA was associated with better cardiometabolic parameters and LDL particle quality.

2.
Biol Blood Marrow Transplant ; 26(11): 2027-2033, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32682949

RESUMO

Allogeneic hematopoietic cell transplantation (HCT) is the treatment of choice for acute myelogenous leukemia (AML) not responding to induction therapy. It is a therapeutic choice for the blast phase of chronic myelogenous leukemia (CML-BP) in patients failing to respond to tyrosine kinase inhibitors (TKIs). Lipid core nanoparticles (LDEs) concentrate severalfold more in blast cells than in corresponding normal cells. Incorporation of anticancer drugs to LDE formulations increases the pharmacologic action and decreases the toxicity. We tested a drug-targeting system, LDE-etoposide plus total body irradiation (TBI; 1200 cGy dose), in 13 patients with AML not responding to the induction therapy and in 2 patients with CML-BP refractory to second-generation TKIs. The mean patient age was 46.7 years (range, 22 to 66 years). The LDE-etoposide dose was escalated at 20, 30, 40, 50, and 60 mg/kg. No patients developed grade 4 or 5 toxicity; however, mucositis grade 3 occurred in 6 patients, 3 patients experienced diarrhea, and 1 patient had an elevated total bilirubin level. No deaths were related to conditioning. All patients were successfully engrafted. The median times to neutrophil and platelet engraftment were 20 ± 5 days and 16 ± 4 days, respectively. Five patients (33.4%) had acute graft-versus-host-disease (GVHD), including 4 grade I, and 1 with grade II, and 8 patients (57.1%) had moderate-to-severe chronic GVHD. This pilot study shows the potential of LDE-etoposide plus TBI as an HCT conditioning regimen in AML patients not responding to the induction and refractory therapies for CML-BP patient. These findings pave the way for subsequent larger clinical trials.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Nanopartículas , Adulto , Idoso , Medula Óssea , Etoposídeo/uso terapêutico , Humanos , Quimioterapia de Indução , Leucemia Mieloide Aguda/terapia , Lipídeos , Pessoa de Meia-Idade , Projetos Piloto , Condicionamento Pré-Transplante , Transplante Homólogo , Irradiação Corporal Total , Adulto Jovem
3.
Clinics ; Clinics;74: e989, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1011914

RESUMO

OBJECTIVE: Rapidly dividing cells in multiple types of cancer and inflammatory diseases undergo high low density lipoprotein (LDL) uptake for membrane synthesis, and coupling an LDL-like nanoemulsion, containing lipid nanoparticles (LDE) to a chemotherapeutic agent efficiently targets these cells without significant systemic effects. This was a prospective exploratory study that evaluated the uptake of a radioactively labeled LDE emulsion by receptors of endometriotic foci and the capacity of the LDE for cellular internalization. METHODS: The lipid profile of each patient was determined before surgery, and labeled LDE were injected into fourteen patients with intestinal or nonintestinal endometriosis. The radioactivity of each tissue sample (intestinal endometriosis, nonintestinal endometriosis, healthy peritoneum, or topical endometrium) was measured. RESULTS: The group with intestinal endometriosis presented higher levels of plasma LDL but lower LDE uptake by foci than the nonintestinal group, suggesting less cell division and more fibrosis. The uptake of LDE was highest in the topical endometrium, followed by the healthy peritoneum, and lowest in the endometriotic lesion. Since the endometriotic foci showed significant LDE uptake, there was likely increased consumption of LDL by these cells, similar to cells in cancers and inflammatory diseases. Plasma cholesterol levels had no influence on LDE uptake, which showed that the direct delivery of the nanoemulsion to target tissues was independent of serum lipoproteins. There were no significant differences in the parameters (p>0.01) because of the small sample size, but the findings were similar to those of previous studies. CONCLUSION: Nanotechnology is a promising therapeutic option for surgery and hormonal blockage for deep endometriosis, with a lower complication rate and no systemic side effects.


Assuntos
Humanos , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Receptores de LDL/uso terapêutico , Nanotecnologia/métodos , Endometriose/terapia , Nanopartículas/uso terapêutico , Estudos Prospectivos , Emulsões , Endometriose/fisiopatologia , Intestinos , Lipídeos , Lipoproteínas LDL
4.
Lipids ; 52(12): 991-998, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29094255

RESUMO

Lipid core nanoparticles (LDE) resembling LDL behave similarly to native LDL when injected in animals or subjects. In contact with plasma, LDE acquires apolipoproteins (apo) E, A-I and C and bind to LDL receptors. LDE can be used to explore LDL metabolism or as a vehicle of drugs directed against tumoral or atherosclerotic sites. The aim was to investigate in knockout (KO) and transgenic mice the plasma clearance and tissue uptake of LDE labeled with 3H-cholesteryl ether. LDE clearance was lower in LDLR KO and apoE KO mice than in wild type (WT) mice (p < 0.05). However, infusion of human apoE3 into the apoE KO mice increased LDE clearance. LDE clearance was higher in apoA-I KO than in WT. In apoA-I transgenic mice, LDE clearance was lower than in apoA-I KO and than in apoA-I KO infusion with human HDL. Infusion of human HDL into the apoA-I KO mice resulted in higher LDE clearance than in the apoA-I transgenic mice (p < 0.05). In apoA-I KO and apoA-I KO infused human HDL, the liver uptake was greater than in WT animals and apoA-I transgenic animals (p < 0.05). LDE clearance was lower in apoE/A-I KO than in WT. Infusion of human HDL increased LDE clearance in those double KO mice. No difference among the groups in LDE uptake by the tissues occurred. In conclusion, results support LDLR and apoE as the key players for LDE clearance, apoA-I also influences those processes.


Assuntos
Apolipoproteínas E/genética , Lipídeos/sangue , Receptores de LDL/genética , Animais , Linhagem Celular , Humanos , Lipoproteínas HDL/administração & dosagem , Camundongos , Camundongos Knockout , Camundongos Transgênicos
5.
Med Oncol ; 34(9): 151, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28756613

RESUMO

Ovarian cancer is often diagnosed at advanced stages, when poorly responsive to standard treatment. First-line treatment consists in schemes including cytoreductive surgery followed by adjuvant chemotherapy schemes with platinum and taxane derivatives. Second-line regimens are based on gemcitabine and liposomal doxorubicin. Third line is often not worthwhile because of the high toxicity with poor response to treatment. Previously, we showed that paclitaxel (PTX) carried in non-protein lipid core nanoparticles (LDE) resembling the chemical structure of LDL has remarkably reduced toxicity. Here, the hypothesis was tested whether PTX-LDE could safely benefit patients in third-line treatment setting. Fourteen women unresponsive to second-line chemotherapy for ovarian cancer, aged 61 ± 10 years, clinical stage IV and TqNqM1, were included. PTX-LDE was administered at 175 mg/m2, 3/3 week dose. Patients were submitted to clinical examinations before each chemotherapy cycle. Serum biochemistry and imaging examinations to monitor disease progression were performed. In total, 74 cycles of chemotherapy were done and, in all cycles, clinical or laboratorial toxicities were not observed. Median progression-free survival (PFS) was 3.0 months (95% CI 2.0-3.9). In four patients, PFS was >6 months and in 2 > 1 year. The unpreceded, striking absence of toxicity and consistently long PFS, compared to previous results, indicate that at least 4 among 14 patients had tumor arrest by the treatment and clear benefit of PTX-LDE at third-line setting. The absence of observable toxicity allows dose escalating to improve response to treatment, as perspective to be tested in the ensuing studies.


Assuntos
Carcinoma/tratamento farmacológico , Lipídeos/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Epitelial do Ovário , Quimioterapia Adjuvante/métodos , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Progressão da Doença , Intervalo Livre de Doença , Doxorrubicina/análogos & derivados , Doxorrubicina/uso terapêutico , Feminino , Humanos , Polietilenoglicóis/uso terapêutico , Gencitabina
6.
Expert Opin Drug Deliv ; 14(10): 1217-1226, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28042707

RESUMO

INTRODUCTION: The toxicity of chemotherapeutic agents, resulting from their low pharmacological index, introduces considerable discomfort and risk to cancer patients. Among several strategies to reduce the toxicity of chemotherapeutic agents, targeted drug delivery is the most promising one. Areas covered: Liposomes, micelles, albumin-based, polymeric, dendritic and lipid core nanoparticles have been used as carriers to concentrate anticancer drugs in neoplastic tissues, and clinical studies of those preparations are reviewed. In most clinical studies, drug delivery systems reduced drug toxicity. Lipid core nanoparticles (LDE) that bind to cell lipoprotein receptors have the ability to concentrate in neoplastic tissues and were the first artificial non-liposomal system shown in in vivo studies to possess targeting properties. The toxicity reduction achieved by LDE as vehicle of carmustine, etoposide and paclitaxel was singularly strong. Expert opinion: The reduced toxicity offered by drug delivery systems has expanded treatment population that may benefit from chemotherapy including feeble, overtreated and elderly patients that would otherwise be offered palliative therapy. Drug delivery systems may either prolong the duration of treatments or allow increases in drug dose.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Animais , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Humanos , Lipídeos/administração & dosagem , Lipídeos/uso terapêutico , Lipídeos/toxicidade , Lipossomos , Nanopartículas/administração & dosagem , Nanopartículas/uso terapêutico , Nanopartículas/toxicidade
7.
J Cell Biochem ; 118(7): 1810-1818, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28012205

RESUMO

Distinct modes of cell migration contribute to diverse types of cell movements. The mesenchymal mode is characterized by a multistep cycle of membrane protrusion, the formation of focal adhesion, and the stabilization at the leading edge associated with the degradation of extracellular matrix (ECM) components and with regulated extracellular proteolysis. Both α2 -Macroglobulin (α2 M) and its receptor, low density lipoprotein receptor-related protein 1 (LRP1), play important roles in inflammatory processes, by controlling the extracellular activity of several proteases. The binding of the active form of α2 M (α2 M*) to LRP1 can also activate different signaling pathways in macrophages, thus inducing extracellular matrix metalloproteinase-9 (MMP-9) activation and cellular proliferation. In the present study, we investigated whether the α2 M*/LRP1 interaction induces cellular migration of the macrophage-derived cell line, Raw264.7. By using the wound-scratch migration assay and confocal microscopy, we demonstrate that α2 M* induces LRP1-mediated mesenchymal cellular migration. This migration exhibits the production of enlarged cellular protrusions, MT1-MMP distribution to these leading edge protrusions, actin polymerization, focal adhesion formation, and increased intracellular LRP1/ß1-integrin colocalization. Moreover, the presence of calphostin-C blocked the α2 M*-stimulated cellular protrusions, suggesting that the PKC activation is involved in the cellular motility of Raw264.7 cells. These findings could constitute a therapeutic target for inflammatory processes with deleterious consequences for human health, such as rheumatoid arthritis, atherosclerosis and cancer. J. Cell. Biochem. 118: 1810-1818, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , alfa-Macroglobulinas/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Matriz Extracelular/metabolismo , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Microscopia Confocal , Naftalenos/farmacologia , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
8.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;50(10): e6225, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888940

RESUMO

Coronary allograft vasculopathy is an inflammatory-proliferative process that compromises the long-term success of heart transplantation and has no effective treatment. A lipid nanoemulsion (LDE) can carry chemotherapeutic agents in the circulation and concentrates them in the heart graft. The aim of the study was to investigate the effects of methotrexate (MTX) associated to LDE. Rabbits fed a 0.5% cholesterol diet and submitted to heterotopic heart transplantation were treated with cyclosporine A (10 mg·kg-1·day-1 orally) and allocated to treatment with intravenous LDE-MTX (4 mg/kg, weekly, n=10) or with weekly intravenous saline solution (control group, n=10), beginning on the day of surgery. Animals were euthanized 6 weeks later. Compared to controls, grafts of LDE-MTX treated rabbits showed 20% reduction of coronary stenosis, with a four-fold increase in vessel lumen and 80% reduction of macrophage staining in grafts. Necrosis was attenuated by LDE-MTX. Native hearts of both LDE-MTX and Control groups were apparently normal. Gene expression of lipoprotein receptors was significantly greater in grafts compared to native hearts. In LDE-MTX group, gene expression of the pro-inflammatory factors tumor necrosis factor-α, monocyte chemoattractant protein-1, interleukin-18, vascular cell adhesion molecule-1, and matrix metalloproteinase-12 was strongly diminished whereas expression of anti-inflammatory interleukin-10 increased. LDE-MTX promoted improvement of the cardiac allograft vasculopathy and diminished inflammation in heart grafts.


Assuntos
Animais , Coelhos , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/efeitos adversos , Imunossupressores/administração & dosagem , Lipídeos/administração & dosagem , Metotrexato/administração & dosagem , Nanopartículas/administração & dosagem , Aloenxertos , Imunossupressores/farmacologia , Metotrexato/farmacologia , Nanopartículas/química
9.
Clinics ; Clinics;71(8): 435-439, Aug. 2016. tab
Artigo em Inglês | LILACS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: lil-794635

RESUMO

OBJECTIVE: The toxicity of anti-cancer chemotherapeutic agents can be reduced by associating these compounds, such as the anti-proliferative agent paclitaxel, with a cholesterol-rich nanoemulsion (LDE) that mimics the lipid composition of low-density lipoprotein (LDL). When injected into circulation, the LDE concentrates the carried drugs in neoplastic tissues and atherosclerotic lesions. In rabbits, atherosclerotic lesion size was reduced by 65% following LDE-paclitaxel treatment. The current study aimed to test the effectiveness of LDE-paclitaxel on inpatients with aortic atherosclerosis. METHODS: This study tested a 175 mg/m2 body surface area dose of LDE-paclitaxel (intravenous administration, 3/3 weeks for 6 cycles) in patients with aortic atherosclerosis who were aged between 69 and 86 yrs. A control group of 9 untreated patients with aortic atherosclerosis (72-83 yrs) was also observed. RESULTS: The LDE-paclitaxel treatment elicited no important clinical or laboratory toxicities. Images were acquired via multiple detector computer tomography angiography (64-slice scanner) before treatment and at 1-2 months after treatment. The images showed that the mean plaque volume in the aortic artery wall was reduced in 4 of the 8 patients, while in 3 patients it remained unchanged and in one patient it increased. In the control group, images were acquired twice with an interval of 6-8 months. None of the patients in this group exhibited a reduction in plaque volume; in contrast, the plaque volume increased in three patients and remained stable in four patients. During the study period, one death unrelated to the treatment occurred in the LDE-paclitaxel group and one death occurred in the control group. CONCLUSION: Treatment with LDE-paclitaxel was tolerated by patients with cardiovascular disease and showed the potential to reduce atherosclerotic lesion size.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Doenças da Aorta/tratamento farmacológico , Colesterol/uso terapêutico , Paclitaxel/uso terapêutico , Aterosclerose/tratamento farmacológico , Moduladores de Tubulina/uso terapêutico , Nanopartículas/uso terapêutico , Aorta Torácica/efeitos dos fármacos , Doenças da Aorta/diagnóstico por imagem , Fatores de Tempo , Triglicerídeos/sangue , Angiografia , Colesterol/sangue , Reprodutibilidade dos Testes , Resultado do Tratamento , Sistemas de Liberação de Medicamentos , Aterosclerose/diagnóstico por imagem , Emulsões Gordurosas Intravenosas/uso terapêutico , Tomografia Computadorizada Multidetectores
10.
Int J Nanomedicine ; 6: 2297-304, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22072867

RESUMO

OBJECTIVES: Cholesterol-rich nanoemulsions (LDE) bind to low-density lipoprotein (LDL) receptors and after injection into the bloodstream concentrate in aortas of atherosclerotic rabbits. Association of paclitaxel with LDE markedly reduces the lesions. In previous studies, treatment of refractory cancer patients with etoposide associated with LDE had been shown devoid of toxicity. In this study, the ability of etoposide to reduce lesions and inflammatory factors in atherosclerotic rabbits was investigated. METHODS: Eighteen New Zealand rabbits were fed a 1% cholesterol diet for 60 days. Starting from day 30, nine animals were treated with four weekly intravenous injections of etoposide oleate (6 mg/kg) associated with LDE, and nine control animals were treated with saline solution injections. RESULTS: LDE-etoposide reduced the lesion areas of cholesterol-fed animals by 85% and intima width by 50% and impaired macrophage and smooth muscle cell invasion of the intima. Treatment also markedly reduced the protein expression of lipoprotein receptors (LDL receptor, LDL-related protein-1, cluster of differentiation 36, and scavenger receptor class B member 1), inflammatory cytokines (interleukin-1ß and tumor necrosis factor-α), matrix metallopeptidase-9, and cell proliferation markers (topoisomerase IIα and tubulin). CONCLUSION: The ability of LDE-etoposide to strongly reduce the lesion area and the inflammatory process warrants the great therapeutic potential of this novel preparation to target the inflammatory-proliferative basic mechanisms of the disease.


Assuntos
Aterosclerose/tratamento farmacológico , Colesterol/administração & dosagem , Etoposídeo/farmacologia , Nanoestruturas/administração & dosagem , Animais , Aterosclerose/sangue , Aterosclerose/metabolismo , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Ingestão de Alimentos/efeitos dos fármacos , Emulsões/administração & dosagem , Emulsões/farmacologia , Emulsões/toxicidade , Eritrócitos/efeitos dos fármacos , Etoposídeo/toxicidade , Histocitoquímica , Leucócitos/efeitos dos fármacos , Lipoproteínas/sangue , Masculino , Nanoestruturas/toxicidade , Coelhos , Receptores de LDL/sangue , Testes de Toxicidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA