ABSTRACT
Self-assembling carrier-free nanodrugs are attractive agents because they accumulate at tumor by an enhanced permeability and retention (EPR) effect without introduction of inactive substances, and some nanodrugs can alter the immune environment. We synthesized a peptidyl arginine deiminase 4 (PAD4) molecular inhibitor, ZD-E-1M. It could self-assembled into nanodrug ZD-E-1. Using confocal laser scanning microscopy, we observed its cellular colocalization, PAD4 activity and neutrophil extracellular traps (NETs) formation. The populations of immune cells and expression of immune-related proteins were determined by single-cell mass cytometry. ZD-E-1 formed nanoflowers in an acidic environment, whereas it formed nanospheres at pH 7.4. Accumulation of ZD-E-1 at tumor was pH-responsive because of its pH-dependent differences in the size and shape. It could enter the nucleus and bind to PAD4 to prolong the intracellular retention time. In mice, ZD-E-1 inhibited tumor growth and metastasis by inhibiting PAD4 activity and NETs formation. Besides, ZD-E-1 could regulate the ratio of immune cells in LLC tumor-bearing mice. Immunosuppressive proteins like LAG3 were suppressed, while IFN-γ and TNF-α as stimulators of tumor immune response were upregulated. Overall, ZD-E-1 is a self-assembling carrier-free nanodrug that responds to pH, inhibits PAD4 activity, blocks neutrophil extracellular traps formation, and improves the tumor immune microenvironment.
ABSTRACT
Objective: To optimize preparation of mitochondrial targeting hyperoside liposomes (DLD/Hyp-Lip), and study its stability in fetal bovine serum, in vitro release behavior and mitochondrial targeting. Methods: DLD/Hyp-lip was prepared by film dispersion method. Single factor experiment was carried out with entrapment efficiency and drug loading as indexes to investigate the effects of the ratio of phospholipids to hyperoside (Hyp) and DSPE-PEG (distearoyl phosphoethanolamine-polyethylene glycol) to DLD on DLD/Hyp-Lip. The formulation of DLD/Hyp-Lip was further optimized by central composite design response surface methodology. The appearance, size and potential of liposomes were observed by transmission electron microscope and particle size analyzer. The stability and drug release rate of liposomes in fetal bovine serum were evaluated by serum stability test and in vitro drug release test. The drug delivery system was evaluated by mitochondrial targeting. Results: The optimal formula of DLD/ Hyp-Lip was as follows: the ratio of total phospholipids to hyperoside was 12.50:1, the ratio of total phospholipids to cholesterol was 6.00:1, and the dosage ratio of DSPE-PEG to DLD was 3:5, the encapsulation efficiency was (95.57 ± 0.56) %, the drug loading was (8.55 ± 0.57) %. The prepared liposomes had good appearance, the particle size of the lip was (124.9 ± 3.4) nm, and the potential was (-6.2 ± 1.9) mV. It was stable in fetal bovine serum and accumulated in vitro release medium for 24 h. Mitochondrial targeting experiments showed that DLD/Hyp-Lip could promote the accumulation of drugs in the mitochondria. Conclusion: This method is simple and convenient, and can accurately and effectively optimize the preparation process of DLD/Hyp-Lip. The prepared DLD/Hyp-Lip has high encapsulation efficiency, small particle size, uniform distribution and good sustained-release effect, which lays the foundation for further in vivo research of DLD/Hyp-Lip. DLD/Hyp-Lip with hyperoside has good mitochondrial targeting of liver cancer cells and is a potentially efficient mitochondrial targeted drug delivery system for liver cancer cells.
ABSTRACT
Objective: To enhance the blood-brain barrier (BBB) penetration and glioma targeting ability of arsenic trioxide (As2O3), the lipid-coated mesoporous silica nanoparticles (MSN) modified with Angiopep-2 and polyacrylic acid (ANG-PAA-LP-MSN) is prepared by thin-film hydration method. This complex is specifically recognized and bound between ANG and low-density lipoprotein receptor-related protein-1 (LRP-1) which is highly expressed on BBB and glioma cells. Methods: The drug delivery system characterization were analysed by transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). Dialysis bag method was used to analyse the drug release characteristics at different pH conditions (pH 6.0 and 7.4, respectively). Cytotoxicity of nanocarriers and the antitumor activity in vitro of this drug delivery system were measured on human brain micro-capillary endothelial cells (HBMEC) and glioma cells (C6) by MTT assay. Moreover, in vitro cells model of BBB was established to study the effect of vehicle on the transmembrane transport of As2O3. Results: The drug delivery system (ANG-PAA-LP-MSN@As2O3) was constructed successfully, it showed a rounded "core-shell" structure with good dispersibility and stability. The drug loading efficency was 6.32%. After PAA modification, this drug delivery system showed higher pH responsiveness to release medium, and the burst release of As2O3 was significantly reduced compared with that of unmodified group. Lipid coating could significantly improve the biosafety and penetration ability of BBB. The antitumor activity study showed that ANG-PAA-LP-MSN@As2O3 exhibited an ideal glioma inhibition effect in vitro. Conclusion: This smart targeting drug delivery system enhance the BBB penetration ability of As2O3, and the special pH responsiveness demonstrated antitumor ability through increasing its accumulation in the tumor site.
ABSTRACT
Objective To prepare docetaxel (DTX) loaded active breast cancer-targeted pH-responsive nanoparticles and to determine its chemo-physical properties, drug loading and releasing characteristics, and targeting ability and cytotoxity against MCF-7 cells. Methods The nanoparticles were synthesized by nanoprecipitation method and surface modification based on polydopamine (PDA). The morphology, size and zeta potential, and surface modification of the nanoparticles were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS) and X-ray photoelectron spectroscopy (XPS). respectively. Drug loading content, encapsulation efficiency, and in vitro drug release profiles were measured by dialysis and high performance liquid chromatography (HFLC). The in vitro cellular uptake was analyzed by confocal laser scanning microscope (CLSM) and flow cytometry (FCM), and the the effect of drug-loaded nanoparticles on the viability of MCF-7 cells was determined by MTT assays. Results The DTX loaded nanoparticles, CA-PIGA@PDA-PEG-FA/NPs, exhibited a core-shell structure, with hydrodynamic size of (166. 4 ± 3. 9) nm, zeta potential of (- 11. 7±3. 8) mV, drug loading efficiency of (9. 67 ±0. 45)%, and encapsulation efficiency of (88. 32±3. 10)%. Furthermore, the drug release rate of the nanoparticles in pH 5. 0 release medium was faster than that in pH 7. 4. XPS spectra showed that PDA and folic acid were modified on the surface of the nanoparticles. The active targeting nanoparticles ingested by MCP-7 cells were more than the nanoparticles not linked to active targeting ligands, and the cytotoxicity of active-targeted nanoparticles was significantly superior than that of Taxotere® (clinical preparation of DTX). Conclusion The active breast cancer targeted pH responsive nanoparticles (DTX-loaded CA-PLGA@ PDA-PEG-FA/NPs) exhibits promising targeting ability and efficient antitumor activity in vitro against MCF-7 cells.