Nanostructured lipid carriers as a novel tool to deliver sclareol: physicochemical characterisation and evaluation in human cancer cell lines

Sclareol (SC) is arousing great interest due to its cytostatic and cytotoxic activities in several cancer cell lines. However, its hydrophobicity is a limiting factor for its in vivo administration. One way to solve this problem is through nanoencapsulation. Therefore, solid lipid nanoparticles (SLN-SC) and nanostructured lipid carriers (NLC-SC) loaded with SC were produced and compared regarding their physicochemical properties. NLC-SC showed better SC encapsulation than SLN-SC and was chosen to be compared with free SC in human cancer cell lines (MDA-MB-231 and HCT-116). Free SC had slightly higher cytotoxicity than NLC-SC and produced subdiploid DNA content in both cell lines. On the other hand, NLC-SC led to subdiploid content in MDA-MB-231 cells and G2/M checkpoint arrest in HCT-116 cells. These findings suggest that SC encapsulation in NLC is a way to allow the in vivo administration of SC and might alter its biological properties

Hyaluronic acid-coated nanoemulsions loaded with a hydrophobic ion pair of all-trans retinoic acid for improving the anticancer activity

All-trans retinoic acid (ATRA) has been studied for the treatment of cancer, including leukemia and breast cancer. This work aims to develop nanoemulsions (NE) loaded with a hydrophobic ion pair (HIP) of all-trans retinoic acid (ATRA) and a lipophilic amine, stearylamine (SA), and coated with hyaluronic acid (HA) to enhance anticancer activity and reducing toxicity. Blank NE was prepared by spontaneous emulsification and optimized prior to HIP incorporation. NE-ATRA was electrostatically coated with different concentrations of HA. Incorporation of ATRA-SA led to monodisperse NE with small size (129 ± 2 nm; IP 0.18 ± 0.005) and positive zeta potential (35.7 ± 1.0 mV). After coating with 0.5 mg/mL HA solution, the mean diameter slightly increased to 158 ± 5 nm and zeta potential became negative (-19.7 ± 1.2 mV). As expected, high encapsulation efficiency (near 100%) was obtained, confirmed by polarized light microscopy and infrared analysis. Formulations remained stable over 60 days and release of ATRA from NE was delayed after the hydrophilic HA-coating. HA-coated NE-ATRA was more cytotoxic than free ATRA for MDA-MB-231 and MCF-7 breast cancer cell lines, especially in the CD44 overexpressing cells. Blank coated formulations showed no cytotoxicity. These findings suggest that this easily-made HA-coated NE-ATRA formulation is a promising alternative for parenteral administration, thus improving the breast cancer therapy with this drug.

Efeito de uma formulação hidrofílica de paromomicina tópica na leishmaniose cutânea em pacientes com contra-indicações de tratamento com antimonial pentavalente / Effect of a hydrophilic formulation of topical paromomycin on cutaneous leishmaniasis among patients with contraindications for treatment with pentavalent antimonials

Descrevem-se o efeito terapêutico e os eventos adversos associados com o uso tópico de paromomicina 10 por cento em gel na leishmaniose cutânea. Quinze pacientes com leishmaniose cutânea cumpriram os critérios de inclusão descritos a seguir: contra-indicação para o uso de antimoniato de meglumina, intradermorreação de Montenegro positiva e até quatro lesões ulceradas. A fórmula foi prescrita duas vezes ao dia por 20 dias. Quatorze pacientes estiveram disponíveis para a avaliação do desfecho terapêutico e a proporção de cura foi de 21,4 por cento (3/14), 50 por cento melhoraram até a epitelização completa e a proporção de falha foi de 28,6 por cento. Nove pacientes que não apresentaram cura inicialmente foram re-tratados. Oito receberam uma nova série de paromomicina tópica e um foi tratado com antimoniato de meglumina. Dois pacientes não receberam novo tratamento e tiveram melhora lenta e contínua. Cinco de oito pacientes retratados com paromomicina tópica alcançaram a cura clínica, e três apresentaram falha, incluindo um paciente que tinha apresentado melhora com o primeiro tratamento. Os eventos adversos foram leves e locais em 53,3 por cento dos pacientes e nunca levaram à suspensão do tratamento.

The therapeutic effect of and adverse events associated with topical use of 10 percent paromomycin gel on cutaneous leishmaniasis are described. Fifteen patients with cutaneous leishmaniasis fulfilled the following inclusion criteria: contraindication for the use of meglumine antimoniate, positive Montenegro skin test and up to four ulcerated lesions. The formula was prescribed twice a day for 20 days. Fourteen patients were available for the therapeutic outcome evaluation. The cure rate was 21.4 percent (3/14); 50 percent improved as far as complete epithelialization; and the failure rate was 28.6 percent. Nine patients who did not initially present cure were retreated. Eight received a new series of topical paromomycin and one was treated with meglumine antimoniate. Two patients did not receive any new treatment and had continuous slow improvement. Five out of the eight patients retreated with topical paromomycin achieved clinical cure, and three presented failure, including one patient who had shown any improvement with the first treatment. For 53.3 percent of the patients, the adverse events were mild and local and never led to treatment suspension.

Influence of the formulation type (o/w, w/o/w emulsions and ointment) on the topical delivery of paromomycin

Ointments containing paromomycin (PA) have been used for topical treatment of cutaneous leishmaniasis. Although influence of the vehicle on skin permeation is crucial for optimization of formulations containing PA, this aspect has not been investigated experimentally. In this study, we have evaluated the influence of the formulation type [oil-in-water (o/w), water-in-oil-in-water (w/o/w) emulsions and ointment] on in vitro release and skin permeation of PA and experiments were carried out on cellulose acetate membrane and skin biopsies from hairless mice, respectively. PA release from o/w emulsion (51.7 por cento ± 0.9 of dose applied) was faster than that observed for w/o/w emulsion (3.0 por cento ± 0.5)...

Emulsöes múltiplas A/O/A contendo paromomicina para tratamento tópico da leishmaniose cutânea: obtençäo, caracterizaçäo e estabilidade / W/O/W multiple emulsion with paromomycin to the topical treatment of cutaneous leishmaniasis: achievement, characterization and stability

Os antimoniais pentavalentes são os fármacos de escolha para o tratamento da leishmaniose cutânea (LC). Entretanto, este tratamento é longo, requer doses repetidas, com graves efeitos adversos. Como um tratamento alternativo, a terapia local pode ser de valor, devido à sua segurança e simplicidade de administração. O sulfato de paromomicina (PA) tem sido testado em uma pomada na concentração de 15 por cento. Embora esse tratamento tenha mostrado resultados promissores, não tem sido eficaz em acelerar a recuperação em muitos dos casos. o objetivo deste estudo foi desenvolver uma emulsão múltipla A/O/A contendo PA para o tratamento tópico da LC...