RESUMO
The purpose of present investigation was to nano-encapsulate atypical antipsychotic such as Olanzapine in polymeric nanoparticles in order to explore the possibility of minimizing drug associated extrapyramidal adverse effects. The polymeric nanoparticulate systems were prepared using FDA approved polymer, polycaprolactone, by simple technique of nanoprecipitation using factorial design by DoE approach. The significant factors selected for the optimization during formulation development process were polymer content and surfactant concentration at three different levels (32 factorial design). The effect of selected significant factors were studied in depth on significant responses such as particle size and encapsulation efficiency. The optimized formulation was further surface modified with surfactant (polysorbate 80) so as to enhance the brain targeting efficiency of developed nanoparticles via endocytosis pathway. Furthermore, catalepsy was induced in rodent model and the designed formulations were investigated in comparison with pure drug solution for efficiency in decreasing extrapyramidal adverse effects. The results of in vitro characterization studies demonstrated a narrow size distributed nanoparticles (73.28⯱â¯2.14â¯nm) with high stability indicating zetapotential (-32.46⯱â¯1.15â¯mV) and high encapsulation efficiency (78.77⯱â¯2.83%). In vitro release studies resulted in an extended release of atypical antipsychotic for 60â¯h from drug-loaded optimized nanoparticulate formulations. The catalepsy studies in rodent model demonstrated a significant decrease in extra pyramidal adverse effects as compared to the pure atypical antipsychotic. Thus, the designed antipsychotic loaded polymeric nanoparticulate system may be highly promising for the tremendous improvement of antipsychotic therapy with reduced adverse effects.
Assuntos
Antipsicóticos/administração & dosagem , Benzodiazepinas/administração & dosagem , Catalepsia/induzido quimicamente , Composição de Medicamentos/métodos , Poliésteres/química , Administração Intravenosa , Animais , Antipsicóticos/efeitos adversos , Benzodiazepinas/efeitos adversos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/efeitos adversos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Humanos , Masculino , Nanopartículas/química , Olanzapina , Tamanho da Partícula , Ratos , Ratos Wistar , Tensoativos/químicaRESUMO
The present paper discusses the design, characterization and in vivo evaluation of glyceryl monostearate nanoparticles of Olanzapine, an atypical antipsychotic drug for acute schizophrenia treatment, during which hospitalization is mandatory and adverse effects are at its peak. The solid lipid nanoparticulate system was obtained by emulsification-ultra sonication technique wherein three factors such as solid lipid content, concentration of surfactant and drug: solid lipid ratio were selected at three different levels in order to study their influence on significant characteristic responses such as particle size, encapsulation efficiency and drug content. A Box Behnken design with 17 runs involving whole factors at three levels was employed for the study. The optimized formulation was further coated with Polysorbate 80 in order to enhance its brain targeting potential through endocytosis transport process via blood brain barrier. The designed formulations were pre-clinically tested successfully in Wistar rat model for in vivo antipsychotic efficacy (apomorphine induced psychosis) and adverse effects (weight gain study for 28days). The results obtained indicated that solid lipid nanoparticles had very narrow size distribution (151.29±3.36nm) with very high encapsulation efficiency (74.51±1.75%). Morphological studies by SEM have shown that solid lipid nanoparticles were spherical in shape with smooth surface. Olanzapine-loaded nanoparticles prepared from solid lipid, extended the release of drug for 48h, as found by the in vitro release studies. The formulations also exhibited high redispersibility after freeze-drying and stability study results demonstrated good stability, with no significant change for a period of 6months. In vivo evaluation and adverse effects studies of Olanzapine-loaded nanoparticulate systems in animal model have demonstrated an improved therapeutic efficacy than pure Olanzapine. The antipsychotic effect of drug loaded nanoparticulate systems was maintained for 48h as compared to 8h antipsychotic action of pure Olanzapine solution. The weight gain studies for 28days demonstrated a significant inhibition in weight gain for Olanzapine-loaded nanoparticulate systems as compared to the pure Olanzapine. The present research findings indicate that OLN-loaded nanoparticulate systems may be highly promising for effective delivery of Olanzapine with better efficacy and minimum adverse effects.