RESUMO
This work investigated the safety of extracts obtained from plants growing in Colombia, which have previously shown UV-filter/antigenotoxic properties. The compounds in plant extracts obtained by the supercritical fluid (CO2) extraction method were identified using gas chromatography coupled to mass spectrometry (GC/MS) analysis. Cytotoxicity measured as cytotoxic concentration 50% (CC50) and genotoxicity of the plant extracts and some compounds were studied in human fibroblasts using the trypan blue exclusion assay and the Comet assay, respectively. The extracts from Pipper eriopodon and Salvia aratocensis species and the compound trans-ß-caryophyllene were clearly cytotoxic to human fibroblasts. Conversely, Achyrocline satureioides, Chromolaena pellia, and Lippia origanoides extracts were relatively less cytotoxic with CC50 values of 173, 184, and 89 µg/mL, respectively. The C. pellia and L. origanoides extracts produced some degree of DNA breaks at cytotoxic concentrations. The cytotoxicity of the studied compounds was as follows, with lower CC50 values representing the most cytotoxic compounds: resveratrol (91 µM) > pinocembrin (144 µM) > quercetin (222 µM) > titanium dioxide (704 µM). Quercetin was unique among the compounds assayed in being genotoxic to human fibroblasts. Our work indicates that phytochemicals can be cytotoxic and genotoxic, demonstrating the need to establish safe concentrations of these extracts for their potential use in cosmetics.
Assuntos
Sobrevivência Celular , Fibroblastos , Extratos Vegetais , Protetores Solares , Humanos , Protetores Solares/toxicidade , Protetores Solares/química , Extratos Vegetais/toxicidade , Extratos Vegetais/química , Fibroblastos/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Salvia/química , Dano ao DNA/efeitos dos fármacos , Células Cultivadas , Lippia/química , Cromatografia Gasosa-Espectrometria de MassasRESUMO
Multidrug resistance (MDR) is the main challenge in cancer treatment. In this sense, we designed transferrin (Tf)-conjugated PLGA nanoparticles (NPs) containing an organoselenium compound as an alternative to enhance the efficacy of cancer therapy and sensitize MDR tumor cells. Cytotoxicity studies were performed on different sensitive tumor cell lines and on an MDR tumor cell line, and the Tf-conjugated NPs presented significantly higher antiproliferative activity than the nontargeted counterparts in all tested cell lines. Due to the promising antitumor activity of the Tf-decorated NPs, further studies were performed using the MDR cells (NCI/ADR-RES cell line) comparatively to one sensitive cell line (HeLa). The cytotoxicity of NPs was evaluated in 3D tumor spheroids and, similarly to the results achieved in the 2D assays, the Tf-conjugated NPs were more effective at reducing the spheroid's growth. The targeted Tf-NPs were also able to inhibit tumor cell migration, presented a higher cell internalization and induced a greater number of apoptotic events in both cell lines. Therefore, these findings evidenced the advantages of Tf-decorated NPs over the nontargeted counterparts, with the Tf-conjugated NPs containing an organoselenium compound representing a promising drug delivery system to overcome MDR and enhance the efficacy of cancer therapy.
RESUMO
In this study, we developed PLGA nanoparticles (NPs) as an effective carrier for 5'-Se-(phenyl)-3-(amino)-thymidine (ACAT-Se), an organoselenium compound, nucleoside analogue that showed promising antitumor activity in vitro. The PLGA NPs were prepared by the nanoprecipitation method and modified with a pH-responsive lysine-based surfactant (77KL). The ACAT-Se-PLGA-77KL-NPs presented nanometric size (around 120 nm), polydispersity index values < 0.20 and negative zeta potential values. The nanoencapsulation of ACAT-Se increased its antioxidant (DPPH and ABTS assays) and antitumor activity in MCF-7 tumor cells. Hemolysis study indicated that ACAT-Se-PLGA-77KL-NPs are hemocompatible and that 77KL provided a pH-sensitive membranolytic behavior to the NPs. The NPs did not induce cytotoxic effects on the nontumor cell line 3T3, suggesting its selectivity for the tumor cells. Moreover, the in vitro antiproliferative activity of NPs was evaluated in association with the antitumor drug doxorubicin. This combination result in synergistic effect in sensitive (MCF-7) and resistant (NCI/ADR-RES) tumor cells, being especially able to successfully sensitize the MDR cells. The obtained results suggested that the proposed ACAT-Se-loaded NPs are a promising delivery system for cancer therapy, especially associated with doxorubicin.
RESUMO
In this study, the hepatotoxicity, phototoxicity and photosensitizing potential of free dronedarone (DRO) and its inclusion complexes with ß-cyclodextrin (ß-CD) and 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD), prepared by different methods, were investigated by using in vitro cell-based approaches. The results of the 3T3 NRU phototoxicity assay showed that free DRO and the CD-based inclusion complexes did not present any substantial phototoxic potential. The photosensitizing potential was assessed by using THP-1 cells and IL-8 as a biomarker, and the experimental data confirmed that both the free drug and the inclusion complexes are likely to cause skin photosensitization, as they were able to induce IL-8 release after irradiation. Nevertheless, the inclusion complexes obtained by kneading followed by spray-drying induced a lower IL-8 release and also presented a smaller stimulation index in comparison with free DRO, suggesting a reduction in the photosensitizing potential. Finally, the free drug and inclusion complexes were also tested for hepatotoxicity using HepG2 cells. Even though lower IC50 values were found for the inclusion complexes prepared by kneading followed by spray-drying, there was no significant difference, indicating that the complexation of dronedarone did not induce hepatotoxicity. Overall, the obtained data confirmed that the inclusion complexes prepared by kneading followed by spray-drying, especially those based on HP-ß-CD, appeared to be the most promising formulations and, therefore, could be encouragingly explored in the development of novel pharmaceutical dosage forms containing DRO, presumably with reduced side effects and improved safety profile.
Assuntos
Ciclodextrinas/farmacologia , Ciclodextrinas/toxicidade , Dronedarona/farmacologia , Dronedarona/toxicidade , Hepatócitos/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/toxicidade , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ciclodextrinas/química , Relação Dose-Resposta a Droga , Dronedarona/química , Células Hep G2 , Humanos , Interleucina-8/análise , Interleucina-8/metabolismo , Camundongos , Estrutura Molecular , Células NIH 3T3 , Fármacos Fotossensibilizantes/química , Relação Estrutura-Atividade , Células THP-1RESUMO
Dronedarone is a new antiarrhythmic drug for the treatment of atrial fibrillation. This study investigated the complexation of dronedarone hydrochloride with ßcyclodextrin (ß-CD) and 2hydroxypropilßCD (HP-ß-CD) using three different techniques. The complexes in the solid state were characterized by DSC, TGA, PXRD, FT-IR, SEM and 1H NMR, demonstrating the formation of the inclusion complexes and exhibiting different properties from the pure drug. Its aqueous solubility increased about 4.0-fold upon complexation with ß-CD and HP-ß-CD. The dissolution rate of the drug was notably improved in all tested physiological pH values from 1.2 to 6.8 in the presence of both cyclodextrins. Furthermore, an in vitro cytotoxic assay revealed that the inclusion complexes could reduce the cytotoxic effects of the drug on 3T3 cells. The overall results suggest that the inclusion complexes with ß-CD and HP-ß-CD may be potentially useful in the preparation of novel pharmaceutical formulations containing dronedarone hydrochloride.
Assuntos
Antiarrítmicos/química , Dronedarona/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina/química , Células 3T3 , Animais , Antiarrítmicos/síntese química , Antiarrítmicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Dronedarona/síntese química , Dronedarona/farmacologia , Composição de Medicamentos , Liofilização , Camundongos , Microscopia Eletrônica de Varredura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios XRESUMO
A promising approach to achieve a more efficient antitumor therapy is the conjugation of the active molecule to a nanostructured delivery system. Therefore, the main objective of this research was to prepare nanoparticles (NPs), with the polymer poly (ε-caprolactone) (PCL), as a carrier for the antitumor drug methotrexate (MTX). A pH-responsive behavior was obtained through conjugation of the amino acid-based amphiphile, 77KL, to the NP matrix. The NPs showed mean hydrodynamic diameter and drug entrapment efficiency of 178.5 nm and 20.52%, respectively. Owing to its pH-sensitivity, the PCL-NPs showed membrane-lytic behavior upon reducing the pH value of surrounding media to 5.4, which is characteristic of the endosomal compartments. The in vitro antitumor assays demonstrated that MTX-loaded PCL-NPs have higher antiproliferative activity than free drug in MCF-7 cells and, to a lesser extent, in HepG2 cells. This same behavior was also achieved at mildly acidic conditions, characteristic of the tumor microenvironment. Altogether, the results evidenced the pH-responsive properties of the designed NPs, as well as the higher in vitro cytotoxicity compared to free MTX, representing thus a promising alternative for the antitumor therapy.
Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/farmacologia , Metotrexato/administração & dosagem , Metotrexato/farmacologia , Poliésteres/química , Portadores de Fármacos , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Nanopartículas , Tensoativos , Microambiente Tumoral/efeitos dos fármacosRESUMO
Maceration and Soxhlet methods were used to obtain methanol extracts from a Mexican grape (Ruby Cabernet) pomace and the biological activity and phenolic profiles were compared. The antioxidant capacity was used to evaluate the mechanism of action, using a physiological model (erythrocytes) of damage induced by AAPH-generated free radicals. The extract obtained by maceration presented a total phenolic content twice the one obtained using the Soxhlet method. It also contained the most potent antioxidants, reducing anisotropy in the presence of AAPH to the levels of untreated cells, restoring membrane fluidity, preventing the morphological changes, as demonstrated by scanning electron microscopy (SEM), and providing protection against protein oxidation at the higher concentration. Our work showed that both extracts presented significant antioxidant activity through positive interactions with the lipid bilayer.
Assuntos
Antioxidantes/química , Eritrócitos/efeitos dos fármacos , Fenóis/química , Vitis/química , Radicais Livres , México , Oxirredução , Extratos Vegetais/químicaRESUMO
There has been an increase in the use of botanicals as skin photoprotective agents. Pomegranate (Punica granatum L.) is well known for its high concentration of polyphenolic compounds and for its antioxidant and anti-inflammatory properties. The aim of this study was to analyze the photoprotection provided by P. granatum seed oil nanoemulsion entrapping the polyphenol-rich ethyl acetate fraction against UVB-induced DNA damage in the keratinocyte HaCaT cell line. For this purpose, HaCaT cells were pretreated for 1h with nanoemulsions in a serum-free medium and then irradiated with UVB (90-200 mJ/cm(2)) rays. Fluorescence microscopy analysis provided information about the cellular internalization of the nanodroplets. We also determined the in vitro SPF of the nanoemulsions and evaluated their phototoxicity using the 3T3 Neutral Red Uptake Phototoxicity Test. The nanoemulsions were able to protect the cells' DNA against UVB-induced damage in a concentration dependent manner. Nanodroplets were internalized by the cells but a higher proportion was detected along the cell membrane. The SPF obtained (~25) depended on the concentration of the ethyl acetate fraction and pomegranate seed oil in the nanoemulsion. The photoprotective formulations were classified as non-phototoxic. In conclusion, nanoemulsions entrapping the polyphenol-rich ethyl acetate fraction show potential for use as a sunscreen product.
Assuntos
Acetatos/química , Dano ao DNA/efeitos dos fármacos , Emulsões/farmacologia , Lythraceae/metabolismo , Polifenóis/química , Raios Ultravioleta , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Ensaio Cometa , Dano ao DNA/efeitos da radiação , Emulsões/química , Humanos , Imunoensaio , Interleucina-8/análise , Queratinócitos/citologia , Queratinócitos/metabolismo , Lythraceae/química , Microscopia de Fluorescência , Nanotecnologia , Extratos Vegetais/química , Óleos de Plantas/química , Sementes/química , Sementes/metabolismo , Fator de Proteção SolarRESUMO
The main purpose of the present study is to evaluate the ability of nanoemulsion entrapping pomegranate peel polyphenol-rich ethyl acetate fraction (EAF) prepared from pomegranate seed oil and medium chain triglyceride to protect human erythrocyte membrane from oxidative damage and to assess preliminary in vitro photosafety. In order to evaluate the phototoxic effect of nanoemulsions, human red blood cells (RBCs) are used as a biological model and the rate of haemolysis and photohaemolysis (5 J cm(-2) UVA) is assessed in vitro. The level of protection against oxidative damage caused by the peroxyl radical generator AAPH in human RBCs as well as its effects on bilayer membrane characteristics such as fluidity, protein profile and RBCs morphology are determined. EAF-loaded nanoemulsions do not promote haemolysis or photohaemolysis. Anisotropy measurements show that nanoemulsions significantly retrain the increase in membrane fluidity caused by AAPH. SDS-PAGE analysis reveals that AAPH induced degradation of membrane proteins, but that nanoemulsions reduce the extension of degradation. Scanning electron microscopy examinations corroborate the interaction between AAPH, nanoemulsions and the RBC membrane bilayer. Our work demonstrates that Punica granatum nanoemulsions are photosafe and protect RBCs against oxidative damage and possible disturbance of the lipid bilayer of biomembranes. Moreover it suggests that these nanoemulsions could be promising new topical products to reduce the effects of sunlight on skin.
Assuntos
Dermatite Fototóxica/prevenção & controle , Eritrócitos/efeitos dos fármacos , Lythraceae , Extratos Vegetais/farmacologia , Óleos de Plantas/farmacologia , Polifenóis/farmacologia , Acetatos/química , Antioxidantes/farmacologia , Emulsões/química , Hemólise/efeitos dos fármacos , Humanos , Fluidez de Membrana/efeitos dos fármacos , Microscopia Eletroquímica de Varredura , Nanopartículas/química , SementesRESUMO
PURPOSE: The aim of this study was to evaluate the cytotoxic, phototoxic, genotoxic and photogenotoxic potential of gemifloxacin mesylate (GFM), its main synthetic impurity (SI) and one isolated and structurally elucidated degradation product (DP). METHODS: The neutral red uptake (NRU) and reduction of 2,5-diphenyl-3,-(4,5-dimethyl-2-thiazolyl)tetrazolium bromide (MTT) assays were performed as in vitro endpoints to evaluate cytotoxicity and phototoxicity in a 3T3 cell line, and predict toxicity and/or phototoxicity after systemic administration of the drug. The in vitro alkaline single-cell electrophoresis (comet) assay was used to evaluate the genotoxic and photogenotoxic potential of the substances using the same cell line. RESULTS: The results showed that the SI and the DP are more cytotoxic and phototoxic than the drug GFM using the 3T3 cell line. In the comet assay, the drug GFM was found to be more genotoxic and photogenotoxic than its related substances. CONCLUSIONS: Our findings highlight the relevance of the biological safety studies to increase the knowledge regarding the toxic potential of the related substances, which can be associated with the drug side effects and toxicity.
Assuntos
Fluoroquinolonas/química , Naftiridinas/química , Células 3T3 , Animais , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , DNA/efeitos dos fármacos , DNA/metabolismo , DNA/efeitos da radiação , Fluoroquinolonas/toxicidade , Formazans/química , Gemifloxacina , Camundongos , Naftiridinas/toxicidade , Vermelho Neutro/química , Oxirredução , Sais de Tetrazólio/química , Raios UltravioletaRESUMO
Parastrephia lepidophylla, family Asteraceae, has ancient use in traditional medicine in the region of Tarapacá, Chile. Bioguided fractionation of extracts of this plant was undertaken in the search for compounds with analgesic and antioxidant activity. Two benzofuran derivatives were isolated as the major components of this plant, identified as tremetone 1 and methoxytremetone 6. Remarkably, neither of these showed antioxidant activity, but tremetone 1 exhibited a morphine-like analgesic property. Reduction of this analgesic effect by naloxone suggests a direct effect on opiate receptors as a possible signaling pathway. However, both the low diffusion across lipid membranes (PAMPA assay) and the lipophilicity (Log P) shown by tremetone 1 make elusive the mechanism explaining its induced analgesia.
Assuntos
Analgésicos/farmacologia , Asteraceae/química , Benzofuranos/farmacologia , Extratos Vegetais/farmacologia , Animais , Benzofuranos/isolamento & purificação , Chile , Humanos , Masculino , Medicina Tradicional , Ratos , Ratos Sprague-DawleyRESUMO
The aim of this work was to evaluate possible cytotoxic effects of topical creams and lotions produced with Buriti oil and commercial surfactants on human keratinocytes HaCat and 3T3 embryonic mouse fibroblast cultures. We also aimed to assess the cytotoxicity of the surfactants used to produce the emulsions. The neutral red release (NRR) assay was performed as an in vitro method to evaluate the cytotoxicity of the emulsions in HaCat and 3T3 cell lines and predict potential skin irritation. The Buriti oil emulsions presented low cytotoxicity to the cells at high concentrations and the addition of Vitamin E increased cell viability. Among the surfactant tested, Unitol CE 200F proved to be the most cytotoxic, presenting an IC(50) significantly lower than the others. Emulsions formulated with Buriti oil and commercial surfactants could be non irritant to the skin due to their low cytotoxicity, especially when enhanced with vitamin E. When emulsified with Buriti oil, water and Brij 72, Unitol CE 200F showed less cytotoxic effects than when tested alone.