ABSTRACT
Stimuli-responsive drug delivery systems (DDSs) based on amphiphilic polymers have attracted much attention. In this study, we reported an innovative H2O2-responsive amphiphilic polymer (TBP), bearing a H2O2-sensitive phenylboronic ester, AIE fluorophore tetraphenylethene (TPE) hydrophobic, and polyethylene glycol hydrophilic (PEG) moieties. TBP could self-assemble into micelles with an encapsulation efficiency as high as 74.9% for doxorubicin (DOX) in aqueous solution. In the presence of H2O2, TBP micelles was decomposed by oxidation, hydrolysis and rearrangement, leading to almost 80% DOX release from TBP@DOX micelles. TBP and the corresponding degradation products were biocompatible, while TBP@DOX micelles only displayed obvious toxicity toward cancer cells. Drug delivery process was clearly monitored by confocal laser scanning microscopic (CLSM) and flow cytometry (FCM) analysis. Moreover, in vivo anticancer study showed that TBP@DOX micelles were accumulated in tumor region of nude mice and effectively inhibited tumor growth. The results suggested that the reported H2O2-responsive amphiphilic polymer displayed great potential in drug delivery and tumor therapy.
Subject(s)
Antibiotics, Antineoplastic/pharmacology , Doxorubicin/pharmacology , Drug Delivery Systems , Hydrogen Peroxide/chemistry , Polymers/chemistry , Surface-Active Agents/chemistry , Animals , Antibiotics, Antineoplastic/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Doxorubicin/chemistry , Drug Liberation , Drug Screening Assays, Antitumor , Female , HEK293 Cells , HeLa Cells , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Molecular Structure , Protein Aggregates , Structure-Activity RelationshipABSTRACT
A mitochondria-targetable probe Mito-DHP for nitric oxide (NO) was designed and synthesized by introducing dihydropyridine and triphenylphosphonium (TPP) moieties into boron dipyrromethene (BODIPY) dye. Mito-DHP was able to effectively detect nitric oxide through the aromatization of dihydropyridine to fluorescent pyridine product under oxygen-free conditions. The probe Mito-DHP showed high selectivity to NO over a number of reactive oxygen/nitrogen species (ROS/RNS) as well as high sensitivity (detection limit at 25nM), pH stability and bio-compatibility. Furthermore, Mito-DHP proved to target mitochondria specifically and to visualize both exogenous and endogenous NO in real time.
Subject(s)
Boron Compounds/chemistry , Dihydropyridines/chemistry , Fluorescent Dyes/chemistry , Mitochondria/chemistry , Nitric Oxide/analysis , Animals , Boron Compounds/pharmacology , Cell Survival/drug effects , Dihydropyridines/pharmacology , Fluorescent Dyes/pharmacology , Hep G2 Cells , Humans , Mice , Mitochondria/drug effects , Mitochondria/metabolism , Nitric Oxide/chemistry , Nitric Oxide/metabolism , Organophosphorus Compounds/chemistry , Organophosphorus Compounds/pharmacology , RAW 264.7 CellsABSTRACT
Royalisin found in the royal jelly of Apis mellifera is an antimicrobial peptide (AMP). It has a molecular weight of 5.5 kDa, which contains six cysteine residues. In this study, royalisin was overexpressed in Escherichia coli AD494 (DE3) as two oleosin-fusion proteins for preparation of its antibodies and functional purification. The recombinant royalisin, fused with oleosin central hydrophobic domain in both N- and C-termini, was reconstituted with triacylglycerol and phospholipids to form artificial oil bodies (AOBs). The AOBs were then purified to raise the antibodies. These antibodies could recognize both the native and recombinant royalisins, but not oleosin. Another oleosin-intein S-fusion protein was purified by AOBs system, and royalisin was subsequently released from the AOBs through self-splicing of the intein. The recombinant royalisin exhibited high antibacterial activity, which suggested that it was refolded to its functional structure. These results demonstrated that AOBs system is an efficient method to functionally express and purify small AMPs. In addition, it also provides a facile platform for the production of antibodies against small peptides.