The Bioavailability Enhancement And Mechanism Of Pamam Dendrimer On The Poorly Absorbanle Drugs

In recent years,drug administered via the respiratory tract as an important non-invasive drug delivery systems have obvious advantages,high attention by researchers.However,it is known is that,compared with traditional injection,including proteins and peptides,including hydrophobic drugs and macromolecular drugs after administration via the respiratory system is still significantly lower absorption.Their relatively low bioavailability of the drug was mainly due to the absorption process and the macromolecules can easily be degraded lower respiratory mucosal permeability.Accordingly,the subject has determined that the dendrimer polymer(PAMAM dendrimer)material for potential absorption enhancer used in vivo,in vitro model to investigate PAMAM dendrimer bis difficult to absorb the medication to the system via the respiratory tract absorption promoting effect,and further treated with irrelevant and in vitro PAMAM dendrimer solution clear mechanism of action of absorption enhancers,eventually find a qualified,safe and effective,a clear mechanism of action via the respiratory tract absorption promoters delivery system,for the first time the DNA microarray technology into dendritic polyamide-amine permeable membrane mechanism,allowing research involving animals,cells,molecules three levels in order to seek an efficient and low toxicity,widely used,the mechanism of absorption enhancers specifically as preparation for their future application in clinical materials provide a scientific basis.Specific studies are as follows:1.Establish the cell model of Calu-3.Establish PAMAM dendrimer administered in model.Established in vitro cell culture model Calu-3 cells,inverted microscope cell morphology,cell growth curve,measuring TEER values of integrity inspection of cells,cell permeability fluorescein inspection visits.Experimental results show that the morphology of the cells cultured Institute normal cell experiments TEER greater 500?,indicates that the cell had good integrity,Papp value of less than fluorescein 1 ×10-6cm·s-1,indicate good cellular permeability.Under the conditions of this experiment,the method for culturing cells fast,reliable and easy to use.2.PAMAM dendrimer in vitro toxicity evaluation.Experimental dendritic polyamide-amine administration were used to determine the concentration of tissue sections and MTT method,lung biopsy results show that with the increase of concentration after administration to organize their pathological undergone significant changes,high concentration group that some bronchial epithelial cells necrosis,some alveolar wall destruction,fusion7 alveolar foramen.Low concentration group compared with the control group,no significant differences.MTT law and to deposit in the cell water-insoluble formazan crystal violet absorbance detection index value,negative control group,cell survival rate was 100%,the positive control group,3%of TritonX-100.Experimental results show that,0.1%(w/v)of the dendritic polyamide-amine and Calu-3 cell viability was 90.97±3.98%,and the positive control group,a 3%compared to the survival of TritonX-100,the cell does not have any significant effect,so experiment using 0.1%(w/v)G3 PAM AM dendrimer concentration of the appropriate concentration for administration.3.The influence of PAMAM dendrimer to FD4 transshipment in vitro.The Calu-3 in vitro models,with Hank's solution as a transport medium the FD4 transhipment,on whether to join PAMAM dendrimer,transfer temperature and the presence of organic cation inhibitors respectively,calculate the Papp values.The results show that the join PAMAM dendrimer of FD4 Calu-3 cells after promote the rate of 3.06 times;After joining organic cation transporter protein inhibitions and lower the temperature,FD4 transfer rates is significatly suppressed.4.PAMAM dendrimer transporter in vivo effects on FD4.SD male rats with experimental animals were randomly divided into two groups,with tracheal spray delivery method given in the lungs containing 0.1%(w/v)G3-generation PAMAM dendrimer different after administration of the drug difficult to absorb FD4 solution time taken from the jugular vein of rat blood plasma proteins by methanol precipitation method,using a microplate reader OD values measured at different time points FD4,the standard curve to calculate the plasma concentration.The results showed:0.1%(w/v)G3-generation PAMAM dendrimer for FD4 have more significant role in promoting,promoting ratio of 2.0 times.5.DNA microarray studies.Using DNA microarray technology trends,research and uptake transporter gene family-related expression.Calu-3 cells to absorb model to study the impact of the relevant transporter protein PAMAM dendrimer and models of drug action,locate the relevant gene or protein absorption,the absorption factors evaluated from the effective part of the overall level.Statistical results,a significant change in 26 SLC family of organic cation transporter(OCTs)occurred,of which 22 genes were upregulated,four genes were downregulated,that organic cation transporter proteins involved in the transmembrane transport of PAMAM dendrimer.PAMAM dendrimer amino groups present on the surface,which is the unique physical and chemical properties of PAMAM dendrimer.We suspect that the amino groups may be combined with a cationic transporter cell surface,thus helping the model drug transmembrane transport,and ultimately achieve the purpose of promoting its absorption.6.The mechanism of PAMAM dendrimer.This topic applied Western blot(Western blot)and real-time quantitative PCR on dendritic polyamide-amine the mechanism for further verification.The experimental results show that after two methods of authentication,PAMAM dendrimer group and blank group,an organic cation transporter OCT1,OCT2,OCT3 expression was significantly increased,which was consistent with the microarray,described dendritic poly amide-amine to promote the increased expression of an organic cation,thereby promoting the absorption of drugs.