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1.
Front Cardiovasc Med ; 11: 1342832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450375

RESUMO

Introduction: Studies in cholesterol-fed rabbits showed that anti-proliferative chemotherapeutic agents such as paclitaxel associated with solid lipid nanoparticles (LDE) have marked anti-atherosclerotic effects. In addition, association with LDE nearly abolishes paclitaxel toxicity. We investigated whether treatment with LDE-paclitaxel changes plaque progression by coronary CT angiography and is safe in patients with chronic coronary artery disease. Methods: We conducted a prospective, randomized, double-blind, placebo-controlled pilot study in patients with multi-vessel chronic coronary artery disease. Patients were randomized to receive IV infusions of LDE-paclitaxel (paclitaxel dose: 175 mg/m2 body surface) or LDE alone (placebo group), administered every 3 weeks for 18 weeks. All participants received guideline-directed medical therapy. Clinical and laboratory safety evaluations were made at baseline and every 3 weeks until the end of the study. Analysis of inflammatory biomarkers and coronary CTA was also performed at baseline and 4 weeks after treatment. Results: Forty patients aged 65.6 ± 8 years, 20 in LDE-paclitaxel and 20 in placebo group were enrolled. Among those, 58% had diabetes, 50% had myocardial infarction, and 91% were in use of statin and aspirin. Baseline demographics, risk factors, and laboratory results were not different between groups. In all patients, no clinical or laboratory toxicities were observed. From the baseline to the end of follow-up, there was a non-significant trend toward a decrease in IL-6 levels and hsCRP in the LDE-paclitaxel group (-16% and -28%, respectively), not observed in placebo. Regarding plaque progression analysis, variation in plaque parameter values was wide, and no difference between groups was observed. Conclusion: In patients with multivessel chronic coronary artery disease and optimized medical therapy, LDE-paclitaxel was safe and showed clues of potential benefits in reducing inflammatory biomarkers. Clinical Trial Registration: https://clinicaltrials.gov/study/NCT04148833, identifier (NCT04148833).

2.
Drug Deliv Transl Res ; 10(2): 403-412, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31701487

RESUMO

Leishmaniasis occurs in the five continents and represents a serious public health challenge, but is still a neglected disease, and the current pharmacological weaponry is far from satisfactory. Triglyceride-rich nanoparticles mimicking chylomicrons (TGNP) behave metabolically like native chylomicrons when injected into the bloodstream. Previously we have shown that TGNP as vehicle to amphothericin B (AB) for treatment of fungi infection showed reduced renal toxicity and lower animal death rates compared to conventional AB. The aim of the current study was to test the tolerability and effectiveness of the TGNP-AB preparation in a murine model of Leishmania amazonensis infection. The in vitro assays determined the cytotoxicity of TGNP-AB, AB, and TGNP in macrophages and promastigote forms and the leishmanicidal activity in infected macrophages. The in vivo toxicity tests were performed in healthy mice with increasing doses of TGPN-AB and AB. Then, animals were treated with 2.5 mg/kg/day of AB, 17.5 mg/kg/day of TGNP-AB, or TGNP three times a week for 4 weeks. TGNP-AB formulation was less cytotoxic for macrophages than AB. TGNP-AB was more effective than AB against the promastigotes forms of the parasite and more effective in reducing the number of infected macrophages and the number of amastigotes forms per cell. TGNP-AB-treated animals showed lower hepatotoxicity. In addition, TGNP-AB group showed a marked reduction in lesion size on the paws and parasitic load. The TGNP-AB preparation attained excellent leishmanicidal activity with remarkable lower drug toxicity at very high doses that, due to the toxicity-buffering properties of the nanocarrier, become fully tolerable.


Assuntos
Anfotericina B/administração & dosagem , Antiprotozoários/administração & dosagem , Quilomícrons/química , Leishmaniose Cutânea/tratamento farmacológico , Triglicerídeos/química , Anfotericina B/química , Anfotericina B/farmacologia , Animais , Antiprotozoários/química , Antiprotozoários/farmacologia , Linhagem Celular , Modelos Animais de Doenças , Composição de Medicamentos , Feminino , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Mimetismo Molecular , Nanopartículas , Carga Parasitária
3.
Int J Nanomedicine ; 12: 3827-3837, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28572727

RESUMO

Lipid-based nanoparticle systems have been used as vehicles for chemotherapeutic agents in experimental cancer treatments. Those systems have generally been credited with attenuating the severe toxicity of chemotherapeutic agents. This study aimed to investigate the effects of associating paclitaxel (PTX) with a lipid-based nanoparticle system on a nonhuman primate, Cebus apella, documenting the toxicity as measured by serum biochemistry, which is a detailed analysis of blood and tissue. Eighteen C. apella were studied: three animals were treated with cholesterol-rich nanoemulsion (LDE) only, without PTX, administered intravenously every 3 weeks, during six treatment cycles; six animals were treated with PTX associated with LDE at the same administration scheme, three with lower (175 mg/m2) and three with higher (250 mg/m2) PTX doses; and six animals were treated with commercial PTX, three with the lower and three with the higher doses. In the LDE-PTX group, no clinical toxicity appeared, and the weight-food consumption curve was similar to that of the controls. Two animals treated with commercial PTX presented weight loss, nausea and vomiting, diarrhea, skin flaking, 70% loss of body hair, and decreased physical activity. The use of LDE as a carrier at both lower and higher doses reduced the toxicity of the drug in this species, which is closely related to human subjects. This was observed not only by clinical, biochemical, and hematological profiles but also by the histopathological analysis. The results of this study support the assumption that lipid-based nanoparticle systems used as drug carriers can serve as valuable tools to decrease the toxicity and increase the safety of chemotherapeutic agents.


Assuntos
Antineoplásicos/efeitos adversos , Lipídeos/química , Nanopartículas/efeitos adversos , Paclitaxel/efeitos adversos , Paclitaxel/farmacologia , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Cebus , Colesterol/química , Relação Dose-Resposta a Droga , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/efeitos adversos , Portadores de Fármacos/farmacologia , Emulsões/administração & dosagem , Emulsões/química , Masculino , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Paclitaxel/administração & dosagem , Distribuição Tecidual , Testes de Toxicidade Crônica/métodos
4.
São Paulo; s.n; 2007. 86 p. ilus, tab.
Tese em Português | LILACS | ID: lil-480963

RESUMO

No presente estudo, foram avaliados os efeitos dos esteróides anabólicos androgênicos (EAA) no metabolismo de quilomícrons, lipoproteínas aterogênicas. Uma emulsão lipídica artificial com comportamento metabólico similar aos quilomícrons naturais, marcada com oleato de colesterol e triglicérides radioativos foi injetada endovenosamente em indivíduos praticantes de exercício de força localizada que faziam uso de EAA, em indivíduos que também praticavam exercício de força localizada (EFL), porém não faziam uso de EAA e em indivíduos controles normolipidêmicos e sedentários (CT). A análise compartimental dos dados obtidos das curvas de remoção plasmática da emulsão, foi utilizada para o cálculo das taxas fracionais de remoção (TFR). A TFR do oleato de colesterol do grupo EAA comparando-se as dos grupos EFL e CT, apresentou-se diminuída, enquanto que as TFR dos triglicérides foram similares entre os três grupos...


This study evaluated the effects of Anabolic Androgenic Steroid (AAS) on the metabolism of aterogenic lipoprotein chylomicrons. An artificial lipid emulsion mimicking the behavior of natural chylomicrons, marked with cholesterol oleate and radioactive triglicirides, was endoveneously injected into: individuals who regulalrly weight lifted and regularly made use of AAS, individuals who also regularly weight lifted but did not use AAS and normolipidemic sedentary control individuals. The compartmental analyses of the obtained data from the emulsion decay curves was used to calculate the fractional clearance rate (FCR). The cholesterol oleate FCR for the AAS group was less to the FCR for the weight lifting group that did not use ASS and the control group. However, the trigliceride FCR for the three groups was...


Assuntos
Humanos , Masculino , Adolescente , Adulto , HDL-Colesterol , Quilomícrons/metabolismo , Esteroides , Emulsões Gordurosas Intravenosas
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