Method for active ingredients' in vivo target identification of traditional Chinese medicine using magnetic nanoparticles / 中国中药杂志

Target identification is an important prerequisite for the study of medicine action mechanism. Currently,drug target identification is mostly based on various cell models in vitro. However,the growth microenvironment,nutrition metabolism,biological properties as well as functions are quite different between in vitro cell culture and physiological environment in vivo; wherefore,it is a challenging scientific issue to establish an effective method for identifying drug targets in vivo condition. In this study,we successfully prepared a kind of magnetic nanoparticles( MNPs) which can be chemically modified by the hydroxyl structure of natural bioactive compound echinacoside( ECH) via the epoxy group label on the surface of MNPs. Therefore,organ-selective and recoverable nanoscale target-recognizing particles were prepared. We then intravenously injected the ECH-binding MNPs into rats and distributed them to specific organs in vivo. After cell endocytosis,ECH-binding MNPs captured target proteins in situ for further analysis. Based on this method,we discovered several potential target proteins in the spleen lysates for ECH,and preliminarily clarified the immuno-regulation mechanism of ECH. Collectively,our strategy developed a proof-of-concept technology using nanoparticles for in vivo target identification,and also provided a feasible approach for drug target prediction and pharmacological mechanism exploration.

The feasibility of using magnetic nanoparticles modified as gene vector / Viabilidad del uso de nanopartículas magnéticas modificadas como vectores genéticos

OBJECTIVE: To evaluate the feasibility of using magnetic nanoparticles (MNPs) as gene vector and the effect of magnetic field on efficiency of transfection. METHODS: Magnetic nanoparticles were prepared by controlling some chemical reaction parameters through a partially reduction precipitation method with ferric chloride aqueous solution as precursor material. The surface of particles was modified by polyethyleneimine (PEI) agents. The appearance, the size distribution, structure and phase constitute of MNPs were characterized by Transmission electron microscope (TEM), X-ray diffraction (XRD); the potential of absorbing DNA of MNPs was analysed by electrophoresis. Transfection was determined by delivering reporter gene, PGL2-control encoding luciferase, to different cell lines using MNPs-PLL as vector. The effect of magnetic field on the efficiency of transfection was determined using Nd-Fe-B permanent magnet. RESULTS: Foreign gene could be delivered to various cell lines by MNPs-PLL and expressed with high efficiency but the transfection efficiency and time course varied in the different cell lines studied. Magnetic field could enhance the efficiency of transfection by 5-10 fold. CONCLUSION: MNPs- PLL can be used as a novel non-viral gene vector in vitro, which offers a basis for gene delivery in vivo.

OBJETIVO: Evaluar la viabilidad del uso de nanopartículas magnéticas (MNPs) como vectores genéticos y el efecto de campo magnético en la eficiencia de la transfección. MÉTODOS: Se prepararon nanopartículas magnéticas mediante el control de algunos parámetros de la reacción química a través de un método de precipitación de reducción parcial con soluciones acuosas de cloruro férrico como el material precursor. La superficie de las partículas fue modificada mediante agentes de polietileneimina (PEI). La apariencia, el tamaño, distribución, estructura y constitución de fase de las MNPs, se caracterizaron mediante el microscopio electrónico de transmisión (MET), difracción de rayos X (DRX); el potencial de adsorber ADN de las MNPs se analizó mediante electroforesis; la transfección se determinó mediante el suministro del gene reportador de la luciferasa control PGL2, a diferentes líneas celulares usando MNPs - PLL como vectores. El efecto de campo magnético sobre la eficacia de la transfección se determinó usando el imán permanente NdFeB. RESULTADOS: El gene foráneo pudo suministrarse a varias líneas celulares mediante MNPs - PLL y expresarse con alta eficiencia pero la eficiencia de la transfección y el curso de tiempo variaron en las diferentes líneas celulares estudiadas. El campo magnético pudo mejorar la eficiencia de la transfección en 5-10 veces. CONCLUSION: Las MNPs - PLL pueden usarse como un nuevo vector genético no viral in vito, lo cual ofrece una base para el suministro del gene in vivo.