Research On α-hederin Active Liver Tumor Targeting Drug Delivery System Mediated By Dual Mechanism

Based on the specific recognition ability of galactosylated chitosan (GC) toasialoglycoprotein receptor (ASGPR), identified as a target antigen on hepatoma cells,and of CD147mAb to CD147, over-erpressed on the surface of malignant cells,receptor-mediated active targeting and antibody-mediated active targeting werecombined to achieve nano drug delivery system of α-Hederin nanoparticles associatedwith GC and CD147targeted to hepatocellular carcinoma.Formulation and technology of α-Hed-GC-NPs prepared by emulsion solventdiffusion method were investigted and optimized, and key factors were identified to bedosage of GC (50mg), dosage of lecithin (80mg), and organic phase volume (4mL).α-Hed-GC-NPs optimized were presented a spherical morphology and a unimodal andrelatively narrow particle size distribution, the mean particle diameter was88.70±1.22nm, and its polydispersity index was0.105±0.011, and the average entrapmentefficiency was78.53%±4.39%. Characterization of α-Hed-GC-NPs indicated thatα-Hed were well dispersed in GC carriers, and in vitro release profile showed that drugrelease from nanoparticles was sustained and slightly dependent on pH.α-Hed-GC-CD147-NPs were prepared and compared by coupling method,dissolution method, injection method, adsorption method and modification method,respectively. Particle size determination showed that the mean particle diameters ofα-Hed-GC-CD147-NPs were significantly increased compared with α-Hed-GC-NPs,and the mean particle diameters of nanoparticles prepared by modification method was139.53±4.17nm. Characterization of α-Hed-GC-CD147-NPs by Fourier transforminfrared (FT-IR) spectrophotometer revealed the formation of Intra-and inter molecularhydrogen bonds, indicating the well dispersion of drug in nanoparticles. The conjugatedamount of CD147mAb to α-Hed-GC-CD147-NPs prepared by modification method was1.25μg/mgNP, and the conservation rate of binding activity of mAb was52.29%,prior to nanoparticles prepared by other methods.Cytoxity of α-Hed-GC-CD147-NPs was investigated and compared with other3nanoparticles, α-Hed and its drug-containing nanoparticles can significantly inhibitedthe growth of HepG2and SMMC-7721cells, the inhibitory ability of α-Hed-GC-CD147-NPs was highest, IC50to SMMC-7721and HepG2was23.51±1.22μg/mL and23.30±0.22μg/mL, respectively. Nanoparticles could induce apoptosis of HepG2celland apoptosis rate depended on the dose of α-Hed. The apoptosis rats induced byα-Hed-GC-CD147-NPs at a dose of50,100, and200μg were7.10%,11.87%and25.78%, respectively, higher than that of other nanoparticles. Cellular uptake rates at2hand24h of HepG2cells for α-Hed-GC-CD147-NPs were86.73±11.29%and94.61±4.42%, respectively. With the extension of time, most of nanoparticles wereintaked into slurry, and had access to the cell nucleus, α-Hed-GC-CD147-NPs had astronger affinity to HepG2cell and better ability targeting to liver tumor cells.Acute toxicity in mice by tail vein injection of α-Hed and4nanoparticles wastested and the LD50were above12mg/kg, more than α-Hed. Inhibition rates of tumorweight in HepG2-bearing nude mice of4nanoparticles for3dose groups (0.5,1.0,2.0mg/kg) were all above70%, more than α-Hed (1.0mg/kg). Inhibition rates ofα-Hed-GC-CD147-NPs at doses of0.5,1.0,2.0mg/kg were84.96%,88.25%and92.46,individualy, showed the better liver tumor targeting ability, which was also confirmedby infrared fluorescence imaging.UPLC-MS method for determination of α-Hed in plasma of rats and tissuehomogenate samples of nude mice, and pharmacokinetics in rats and distribution inHepG2-bearing nude mice of α-Hed-GC-CD147-NPs were investigted. α-Hed in ratsshowed a two-compartment model, for α-Hed-GC-NPs, α-Hed-CS-CD147-NPs andα-Hed-GC-CD147-NPs, t1/2(α) were0.12,0.10,0.05h, respectively, t1/2(β) were0.97,2.30,1.93h, respectively. Compared with α-Hed, drug distribution and elimination ofnanoparticles was slowed. Using the AUC of α-Hed as the reference, bioavailability of3nanoparticles above were significantly increased20%,200%and180%respectively.For nanoparticles mediated by antibody or receptor, drug amounts in the liver and tumor tissue is much higher than other organizations, which showed a favorable targetingability to liver or tumor. α-Hed-GC-CD147-NPs, mediated by dual mechanismcombined the receptor-mediated and antibody-mediated active targeting mechanism,drug distribution in liver and tumor of HepG2-bearing nude mice was the highest, andbetter than nanoparticles mediated by single receptor or antibody.