RESUMO
This study aimed to develop microemulsions (MEs) containing α-bisabolol for the topical treatment of cutaneous leishmaniasis (CL). Initially, pseudoternary phase diagrams were developed using α-bisabolol as the oil phase, Eumulgin® CO 40 as the surfactant, Polymol® HE as the co-surfactant, and distilled water as the aqueous phase. Two transparent liquid systems (TLS) containing 5% of α-bisabolol were selected and characterized (F5E25 and F5EP25). Next, skin permeation and retention assays were performed using Franz cells. The interaction of the formulation with the stratum corneum (SC) was evaluated using the FTIR technique. The cytotoxicity was evaluated in murine peritoneal macrophages. Finally, the antileishmanial activity of microemulsions was determined in promastigotes and amastigotes of L. amazonensis (strain MHOM/BR/77/LTB 0016). As a result, the selected formulations showed isotropy, nanometric size (below 25 nm), Newtonian behavior and pH ranging from 6.5 to 6.9. The MEs achieved a 2.5-fold increase in the flux and skin-permeated amount of α-bisabolol. ATR-FTIR results showed that microemulsions promoted fluidization and extraction of lipids and proteins of the stratum corneum, increasing the diffusion coefficient and partition coefficient of the drug in the skin. Additionally, F5E25 and F5EP25 showed higher activity against promastigotes (IC50 13.27 and 18.29, respectively) compared to unencapsulated α-bisabolol (IC50 53.8). Furthermore, F5E25 and F5EP25 also showed antileishmanial activity against intracellular amastigotes of L. amazonensis, with IC50 50 times lower than free α-bisabolol and high selectivity index (up to 15). Therefore, the systems obtained are favorable to topical administration, with significant antileishmanial activity against L. amazonensis promastigotes and amastigotes, being a promising system for future in vivo trials.
RESUMO
Leishmaniases, a group of neglected tropical diseases caused by an intracellular parasite of the genus Leishmania, have significant impacts on global health. Current treatment options are limited due to drug resistance, toxicity, and high cost. This study aimed to develop nanostructured lipid carriers (NLCs) for delivering Citrus sinensis essential oil (CSEO) and its main constituent, R-limonene, against leishmaniasis. The influence of surface-modified NLCs using chitosan was also examined. The NLCs were prepared using a warm microemulsion method, and surface modification with chitosan was achieved through electrostatic interaction. These nanocarriers were characterized by differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy, and dynamic light scattering (DLS). In vitro cytotoxicity was assessed in L929 and RAW 264.7 cells, and leishmanicidal activity was evaluated against promastigote and amastigote forms. The NLCs were spherical, with particle sizes ranging from 97.9 nm to 111.3 nm. Chitosan-coated NLCs had a positive surface charge, with zeta potential values ranging from 45.8 mV to 59.0 mV. Exposure of L929 cells to NLCs resulted in over 70 % cell viability. Conversely, surface modification significantly reduced the viability of promastigotes (93 %) compared to free compounds. Moreover, chitosan-coated NLCs presented a better IC50 against the amastigote forms than uncoated NLCs. Taken together, these findings demonstrate the feasibility of using NLCs to overcome the limitations of current leishmaniasis treatments, warranting further research.
Assuntos
Sobrevivência Celular , Quitosana , Citrus sinensis , Portadores de Fármacos , Limoneno , Lipídeos , Nanopartículas , Óleos Voláteis , Óleos Voláteis/administração & dosagem , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Animais , Camundongos , Limoneno/química , Limoneno/administração & dosagem , Limoneno/farmacologia , Portadores de Fármacos/química , Células RAW 264.7 , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Quitosana/administração & dosagem , Lipídeos/química , Lipídeos/administração & dosagem , Nanopartículas/química , Nanopartículas/administração & dosagem , Citrus sinensis/química , Antiprotozoários/administração & dosagem , Antiprotozoários/farmacologia , Antiprotozoários/química , Leishmaniose/tratamento farmacológico , Tamanho da Partícula , Linhagem Celular , Leishmania/efeitos dos fármacos , Terpenos/química , Terpenos/farmacologia , Terpenos/administração & dosagem , Nanoestruturas/química , Nanoestruturas/administração & dosagemRESUMO
Leishmaniasis are a group of neglected infectious diseases caused by protozoa of the genus Leishmania with distinct presentations. The available leishmaniasis treatment options are either expensive and/or; cause adverse effects and some are ineffective for resistant Leishmania strains. Therefore, molecules derived from natural products as the monoterpene carvacrol, have attracted interest as promising anti-leishmania agents. However, the therapeutic use of carvacrol is limited due to its low aqueous solubility, rapid oxidation and volatilization. Thus, the development of nanostructured lipid carriers (NLCs) was proposed in the present study as a promising nanotechnology strategy to overcome these limitations and enable the use of carvacrol in leishmaniasis therapy. Carvacrol NLCs were obtained using a warm microemulsion method, and evaluated regarding the influence of lipid matrix and components concentration on the NLCs formation. NLCs were characterized by DSC and XRD as well. In addition, to the in vitro carvacrol release from NLCs, the in vitro cytotoxicity and leishmanicidal activity assays, and the in vivo pharmacokinetics evaluation of free and encapsulated carvacrol were performed. NLCs containing carvacrol were obtained successfully using a warm microemulsion dilution method. The NLCs formulation with the lowest particle size (98.42 ± 0.80 nm), narrowest size distribution (suitable for intravenous administration), and the highest encapsulation efficiency was produced by using beeswax as solid lipid (HLB=9) and 5% of lipids and surfactant. The in vitro release of carvacrol from NLCs was fitted to the Korsmeyer and Peppas, and Weibull models, demonstrating that the release mechanism is probably the Fickian diffusion type. Moreover, carvacrol encapsulation in NLCs provided a lower cytotoxicity in comparison to free carvacrol (p<0.05), increasing its in vitro leishmanicidal efficacy in the amastigote form. Finally, the in vivo pharmacokinetics of carvacrol after IV bolus administration suggests that this phenolic monoterpene undergoes enterohepatic circulation and therefore presented a long half-life (t1/2) and low clearance (Cl). In addition, C0, mean residence time (MRT) and Vdss of encapsulated carvacrol were higher than free carvacrol (p < 0.05), favoring a higher distribution of carvacrol in the target tissues. Thus, it is possible to conclude that the developed NLCs are a promising delivery system for leishmaniasis treatment.
Assuntos
Antiprotozoários/administração & dosagem , Cimenos/administração & dosagem , Portadores de Fármacos/administração & dosagem , Leishmania/efeitos dos fármacos , Nanoestruturas/administração & dosagem , Animais , Antiprotozoários/sangue , Antiprotozoários/química , Antiprotozoários/farmacocinética , Sobrevivência Celular/efeitos dos fármacos , Cimenos/sangue , Cimenos/farmacocinética , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Humanos , Leishmaniose/tratamento farmacológico , Lipídeos/administração & dosagem , Lipídeos/química , Lipídeos/farmacocinética , Macrófagos Peritoneais/efeitos dos fármacos , Masculino , Camundongos Endogâmicos BALB C , Nanoestruturas/química , Ratos Wistar , Células THP-1RESUMO
The objective of this study was to develop and characterize lipid nanoparticles (LNs) containing chloroaluminum phthalocyanine (ClAlPc) to reduce the aggregation of the drug and improve its skin penetration and its antitumor effect. LNs were prepared and characterized by using stearic acid (SA) as solid lipid and oleic acid (OA) as liquid lipid in different proportions. in vitro and in vivo skin penetration was evaluated using modified Franz diffusion cells and fluorescence microscopy, respectively. in vitro biocompatibility and Photodynamic Therapy (PDT) were performed using L929-fibroblasts cell line and A549 cancer cell line and melanoma BF16-F10, respectively. OA promoted the increase in the encapsulation efficiency and drug loading, reaching values of 95.8% and 4%, respectively. The formulation with 40% OA (NLC 40) showed a significantly higher (p < 0.01) amount of drug retained in the skin compared to other formulations. All formulations developed were considered biocompatible. PDT evidenced the antitumor efficacy of NLC 40 with reduced cell viability for approximately 10% of cancer cells, demonstrating that the presence of OA in the NLC seems to potentialize this antitumor effect. PDT in BF16-F10 melanoma using NLC 40 resulted in a reduction in mean cell viability of approximately 99%. According to the results obtained, the systems developed may be promising for the incorporation of ClAlPc in the treatment of skin cancer by photodynamic therapy.
Assuntos
Indóis/farmacologia , Nanopartículas/química , Compostos Organometálicos/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Absorção Cutânea/efeitos dos fármacos , Células A549 , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fibroblastos , Humanos , Indóis/administração & dosagem , Camundongos , Ácido Oleico/química , Compostos Organometálicos/administração & dosagem , Tamanho da Partícula , Fármacos Fotossensibilizantes/administração & dosagem , Ácidos Esteáricos/química , SuínosRESUMO
Chitosan treated alginate microparticles were prepared with the purpose of incorporating all-trans retinoic acid (ATRA) using an inexpensive, simple and fast method, enhancing dermal localization and sustaining the release of ATRA into the skin. Microparticles characterization, drug-polymer interaction, release profile and in vitro skin retention were investigated. Microparticles presented spherical shape and drug loading capacity of 47%. The drug content of these microparticles was affected by ATRA concentration and by the solvent used and it was more weakly affected by chitosan concentration. The release of ATRA was also affected by chitosan concentration. Microparticles prepared with 0.4% chitosan (w/w) resulted in drug release with a more sustained profile. The results of in vitro retention studies showed that chitosan treated alginate microparticles decreased the drug retention in the stratum corneum (SC), where occur the skin irritation, but maintained the ATRA concentration in the deeper skin layers, where occur the pathologies treated with ATRA. Then, the microparticles developed in this work can be a good candidate to improve the topical therapy with retinoid.
Assuntos
Alginatos/química , Quitosana/química , Ceratolíticos/administração & dosagem , Pele/metabolismo , Tretinoína/administração & dosagem , Administração Tópica , Animais , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Ceratolíticos/farmacocinética , Microesferas , Suínos , Tretinoína/farmacocinéticaRESUMO
This study aimed at developing a topical formulation of lapachol, a compound isolated from various Bignoniaceae species and at evaluating its topical anti-inflammatory activity. The influence of the pharmaceutical form and different types of emulsifiers was evaluated by in-vitro release studies. The formulations showing the highest release rate were selected and assessed trough skin permeation and retention experiments. It was observed that the gel formulation provided significantly higher permeation and retained amount (3.9-fold) of lapachol as compared to the gel-cream formulation. Antinociceptive and antiedematogenic activities of the most promising formulation were also evaluated. Lapachol gel reduced the increase in hind-paw volume induced by carrageenan injection and reduced nociception produced by acetic acid (0.8% in water, i.p.) when used topically. These results suggest that topical delivery of lapachol from gel formulations may be an effective medication for both dermal and subdermal injuries.