Novel Mitochondrial Targeting Multifunctional Surface Charge-Reversal Polymeric Nanoparticles for Cancer Treatment

Polymeric nanoparticles were widely used as delivery vehicles for targeted delivery of anticancer drugs, because of their targeting property and versatility. Mitochondria are one of the important organelles that regulate the apoptosis of cancer cells and can be considered as a pivotal target for cancer treatment. A pH-responsive charge-reversal and mitochondrial targeting nanoparticles, Vitamin B6-oligomeric hyaluronic acid-dithiodipropionic acid-berberine (B6-oHA-SS-Ber), were prepared in this study. Ber is a lipophilic cation that was conjugated with oHA through disulfide bonds to produce mitochondria-targeted conjugates (oHA-SS-Ber). B6 was conjugated to oHA to obtain B6-oHA-SS-Ber and the two types of Cur-loaded nanoparticles (Cur-NPs) were formulated by the dialysis method. Due to pKa of B6, the charge they carried in the tumor tissue acidic microenvironment can be transferred from negative charge to positive charge, further targeting mitochondria. In our study, we successfully synthesized B6-HA-SS-Ber and characterized the structure by ¹H-NMR. According to the results of transmission electron microscopy (TEM), we found that the B6-oHA-SS-Ber/Cur micelles could self-assembled in water to form spherical nanoparticles, with a hydrodynamic diameter of 172.9±13 nm. Moreover, in vitro cytotoxicity, cellular uptake, lysosome escape and mitochondrial distribution researches revealed the better effect of B6-oHA-SS-Ber/Cur micelles in comparison to oHA-SS-Ber/Cur. In vivo anticancer activities indicated that the B6-oHA-SS-Ber/Cur micelles exhibited effective inhibition of tumor growth.