SUMMARY. Berberine is an isoquinoline alkaloid obtained from different medicinal herbs, including Berberis spp., Coptis spp., and Hydrastis spp. (Imanshahidi and Hosseinzadeh, 2008). It is widely used in medicine and the pharmaceutical industry to prevent and treat disea-ses. However, despite the prominent pharmacological properties of berberine, there are some limitations to its therapeutic application. Polymer nanoparticles may be an effective platform for overcoming these limitations. This study is the first to obtain stable aqueous comple-xes of berberine using three types of polymer carriers. Their synthesis involved the use of polymer-analogue transformations and co-polymerization of PEG-metha-crylate (PEGMA) (Riabtseva et al., 2016). This approach helped control the structural and molecular mass characteristics of new nanocomposites of berberine and their ability to form micellae and their colloid-chemical properties, affecting the biocompatibility of the obtained composites. The study involved a comparative in vitro study of the cytotoxic activity of berberine complexes on three branched polymer carriers: 1) poly(VEP-co-GMA)-graft-mPEG; 2) poly(VEP-co-GMA)-graft-pEtOX; 3) poly(PEGMA-co-DMM). The investigation of cell viability in vitro demonstrated that the used berberine nanocomposites on the polymer carriers had higher toxicity regarding the tumor cells than berberine in its free form. The degree of a decrease in cell viability under the effect of berberine nanocomplexes (PC-PEG-Berb, PC-pEtOx-Berb, PC-PEGMA-Berb) depends on the type of the polymer carrier. At the same time, native polymer carriers (PC-PEG, PC-pEtOx, PC-PEGMA) in a free form do not induce a considerable decrease in cell viability in the concentrations, re-quired for the delivery of 50 mcM berberine, which demonstrates their biocompatibility. The results ob-tained demonstrate promising perspectives of the use of berberine complexes with polymer nanocarriers in antitumor chemotherapy.
Keywords: berberine, polymer nanocarriers, antitumor activity, redox status, apoptosis induction
