RESUMO
Cholesterol-rich nanoemulsion (LDE) can carry chemotherapeutic agents in the circulation and can concentrate those agents in the neoplastic and inflammatory tissues. This method improves the biodistribution of the drug and reduces toxicity. However, the structural stability of LDE particles, without or with associated drugs, has not been extensively investigated. The aim of the present study is to investigate the structural stability of LDE and LDE associated to paclitaxel, etoposide or methotrexate in aqueous solution over time by small-angle X-ray scattering (SAXS and Ultra SAXS) and dynamic light scattering (DLS). The results show that LDE and LDE associated with those chemotherapeutic agents had reproducible and stable particle diameter, physical structure, and aggregation behavior over 3-month observation period. As estimated from both DLS and Ultra-SAXS methods, performed at pre-established intervals, the average particle diameter of LDE alone was approx. 32â¯nm, of LDE-paclitaxel was 31â¯nm, of LDE-methotrexate was 35â¯nm and of LDE-etoposide was 36â¯nm. Ultra-SAXS analysis showed that LDE nanoparticles were quasi-spherical, and SAXS showed that drug molecules inside the particles showed a layered-like organization. Formulations of LDE with associated PTX, ETO or MTX were successfully tested in animal experiments and in patients with cancer or with cardiovascular disease, showing markedly low toxicity, good tolerability and possible superior pharmacological action. Our results may be useful for ensuing clinical trials of this novel Nanomedicine tool, by strengthening the knowledge of the structural aspects of those LDE formulations.
Assuntos
Colesterol , Emulsões , Metotrexato , Nanopartículas , Emulsões/química , Colesterol/química , Nanopartículas/química , Metotrexato/química , Humanos , Animais , Tamanho da Partícula , Paclitaxel/química , Paclitaxel/farmacologia , Espalhamento a Baixo Ângulo , Etoposídeo/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Difração de Raios X , Estrutura MolecularRESUMO
In previous studies, it was demonstrated that lipid core nanoparticles (LDE) resemble the low-density lipoprotein structure and carrying the antiproliferative agent paclitaxel (PTX) strongly reduced atherosclerosis lesions induced in rabbits by cholesterol feeding. Currently, the aim was to verify whether combining LDE-PTX treatment with methotrexate (MTX) associated with LDE (LDE-MTX) could accelerate the atherosclerosis regression attained with single LDE-PTX treatment, after withdrawing the cholesterol feeding. Thirty-eight rabbits were fed 1% cholesterol chow for 8 weeks. Six of these rabbits were then euthanized for analyses of the aorta (controls). In the remaining rabbits, cholesterol feeding was withdrawn, and those 32 animals were allocated to 3 groups submitted to different 8-week intravenous treatments, all once/week: LDE-PTX (n = 10; 4 mg/kg), LDE-PTX + LDE-MTX (n = 11; 4 mg/kg), and LDE-alone (n = 11). Rabbits were then euthanized and aortas were excised for morphometric, immunohistochemical, and gene expression analyses. After cholesterol feeding withdrawal, in comparison with LDE-alone group, both LDE-PTX and LDE-PTX + LDE-MTX treatments had the ability to increase the regression of plaque areas: -49% in LDE-PTX and -59% for LDE-PTX + LDE-MTX. However, only LDE-PTX + LDE-MTX treatment elicited reduction in the intima area, estimated in -57%. Macrophage presence in aortic lesions was reduced 48% by LDE-PTX and 43% by LDE-PTX + LDE-MTX treatment. Matrix metalloproteinase 9 was reduced by either LDE-PTX (74%) or LDE-PTX + LDE-MTX (78%). Tumor necrosis factor α gene expression was reduced 65% by LDE-PTX and 79% by LDE-PTX + LDE-MTX. In conclusion, treatment with LDE-PTX indeed accelerated plaque reduction after cholesterol feeding; LDE-PTX + LDE-MTX further increased this effect, without any observed toxicity. These results pave the way for the use of combined chemotherapy to achieve stronger effects on aggravated, highly inflamed atherosclerotic lesions.
Assuntos
Aorta/efeitos dos fármacos , Doenças da Aorta/prevenção & controle , Aterosclerose/tratamento farmacológico , Fármacos Cardiovasculares/administração & dosagem , Colesterol na Dieta , Lipídeos/química , Metotrexato/administração & dosagem , Nanopartículas , Paclitaxel/administração & dosagem , Placa Aterosclerótica , Animais , Aorta/metabolismo , Aorta/patologia , Doenças da Aorta/sangue , Doenças da Aorta/patologia , Aterosclerose/sangue , Aterosclerose/patologia , Fármacos Cardiovasculares/química , Citocinas/metabolismo , Modelos Animais de Doenças , Composição de Medicamentos , Quimioterapia Combinada , Mediadores da Inflamação/metabolismo , Lipossomos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Metotrexato/química , Paclitaxel/química , CoelhosRESUMO
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 , GencitabinaRESUMO
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/químicaRESUMO
PURPOSE: After injection in the bloodstream, a lipid nanoparticle (LDE) resembling low-density lipoprotein (LDL) concentrates in atherosclerotic lesions of cholesterol-fed rabbits. Here, rabbits with atherosclerosis were treated with carmustine, an antiproliferative agent used in cancer chemotherapy, associated to LDE to investigate the effects on the lesions. METHODS: Twenty-seven male New Zealand rabbits were fed a 1 % cholesterol diet for 8 weeks. After 4 weeks nine animals were treated with intravenous saline solution, nine with intravenous LDE alone, and nine with intravenous LDE-carmustine (4 mg/kg, weekly for 4 weeks). RESULTS: LDE-carmustine reduced lesion size by 90 % compared to the controls. LDE-carmustine reduced the presence of macrophages, vascular smooth muscle cells, and regulatory T cells in the arterial intima, as well as the presence of matrix metallopeptidase-9, interleukin-1ß and TNF-α and lipoprotein receptors, namely LDL-receptor, LDL-related protein-1, scavenger receptor class B member 1. When injected alone, without association to carmustine, LDE was not different from injected saline solution. CONCLUSIONS: LDE-carmustine treatment resulted in marked reduction of lesion area, of the invasion of the arterial intima by macrophages and vascular smooth muscle cells and pro-inflammatory factors. Therefore, this new formulation shows great potential for therapy of atherosclerotic cardiovascular disease.
Assuntos
Aterosclerose/tratamento farmacológico , Carmustina/administração & dosagem , Lipídeos/administração & dosagem , Nanopartículas/administração & dosagem , Animais , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/patologia , Aterosclerose/sangue , Aterosclerose/metabolismo , Aterosclerose/patologia , Carmustina/farmacologia , Carmustina/uso terapêutico , Colesterol na Dieta/administração & dosagem , Interleucina-1beta/metabolismo , Lipídeos/sangue , Lipídeos/química , Lipídeos/uso terapêutico , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Nanopartículas/química , Nanopartículas/uso terapêutico , Coelhos , Receptores de LDL/metabolismo , Receptores Depuradores Classe B/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
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 MultidetectoresRESUMO
A lipid nanoemulsion (LDE) resembling low-density lipoprotein can target malignant tumours. In in vivo and clinical studies, association of chemotherapeutic agents to LDE decreased their toxicity and increased pharmacological action. Here, safety of LDE as carmustine carrier (50 mg m(-2) , intravenous) combined with vincristine and prednisone for the treatment of dogs with lymphoma was tested and compared with commercial carmustine with vincristine and prednisone. In five dogs from LDE-carmustine and six from commercial carmustine, complete remission was achieved (P > 0.05). Partial remission occurred in two dogs from each group. In both groups, the median progression-free intervals (119 and 199 days) and overall survival times (207 and 247 days) were equal. Neutropenia was observed in both groups, but no other major toxicities occurred. Therefore, no difference was observed between the treatments. LDE-carmustine was shown to be safe and effective in a drug combination protocol, which encourages larger studies to investigate the use of this novel formulation to treat canine lymphomas.