The polymeric form ofjosamycin was developed by loading of the antibiotic into spherical submicron particles made of poly(DL- lactide-co-glycolide) (PLGA 50/50) by double emulsion method. The average diameter and zeta-potential of particles synthesized were less than 150 nm and -35 mV respectively. Polymeric form showed antimicrobial activity against gram-positive, gram-negative, and atypical bacteria. The highest antibacterial activity compared to substance (more than 8-fold) was detected against Enterococcus faecalis. The results of in vivo studies of specific activity of drugs on the model of staphylococcal sepsis in mice showed an increase in the efficacy of the studied polymeric form by 1.5-fold compared with the josamycin substance.
Co-encapsulation of abiraterone acetate (AbrA) and docetaxel (Dtx) in polymeric nanoparticles as novel prototypes for prostate cancer treatment combining hormonal and chemotherapy was designed. Nanoparticles (NPs) composed of poly(dl-lactide-co-glycolide) (PLGA) were prepared by single-emulsion solvent evaporation technique and characterized in terms of morphology with atomic force microscopy and transmission electron microscopy. HPLC method for simultaneous determination of AbrA and Dtx encapsulation efficacy was developed. Also differential scanning calorimetry and Fourier-transform infrared spectroscopy were provided. To study the effectiveness of cellular internalization and distribution of NPs with AbrA and Dtx co-encapsulation (NP-AbrA/Dtx), a fluorescence microscopy was utilized. NPs prepared had size 256.3 ±9.4 nm and zeta potential -18.4 ±1.4 mV. Encapsulation efficacy for AbrA was 68.7% and for Dtx was 74.3%. NPs were able to control the AbrA and Dtx release within 24 h. The mathematical model of drug release was performed. The results obtained from confocal microscopy showed the effective accumulation of the NP-AbrA/Dtx in the cytoplasm of cells. Synthesized NPs possessed satisfactory parameters and a biphasic release profile, proceeding by the Fick diffusion mechanism, which provide prolonged release of the drugs and maintenance of their concentration. It was shown that NPs loaded with AbrA and Dtx exhibited a high cytotoxic activity on the LNCaP cell line, similar to the combination of free drugs of AbrA and Dtx, but in contrast to the combination of substances, had a synergistic mechanism of action. Our findings support the potential use of developed NPs in further in vivo studies. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1150-1158, 2019.
Despite the presence of a variety of modern anticancer drugs at the market, doxorubicin (Dox) is still widely used in antineoplastic therapy, although its administration causes severe side effects. To enhance specific activity of such molecules, various approaches have been exploited: targeted moieties like monoclonal antibodies, onco-specific proteins and peptides are utilized as specific vector molecules; environment sensitive linkers are exploited to facilitate transported drug release at the target point etc. Acid-labile linkers are frequently used in synthesis due to the ability to be cleaved inside specific cellular compartments with acidic environment, avoiding possible recycling mechanisms. Two types of conjugates containing different acid-labile linkers have been synthesized. In vitro efficiency of doxorubicin conjugates with recombinant receptor-binding domain of human alpha-fetoprotein (3dAFPpG) synthesized with use of cis-aconitic anhydride (CAA) and linker based on succinimidyl 3-(2-pyridyldithio)propionate (SPDP) and 3-(2-pyridyldithio)propionic acid hydrazide (PDPH) was compared. The 3dAFPpG-SPDP-PDPH-Dox revealed a comparable with unmodified doxorubicin cytotoxic effect against the Dox sensitive MCF7 cell line and greater cytotoxicity against the anthracycline resistant MCF7Adr cells. Meanwhile the 3dAFPpG-CAA-Dox cytotoxic effect was significantly lower, although doxorubicin's pH-dependent release profiles and intracellular accumulation rates were similar. These differences in cytotoxic activity were arguably explained by the dissimilarities in intracellular doxorubicin localization, which may originate from thiol reductase activity in lysosomes and late endosomes.
Silybin (Slb) and ursodeoxycholic acid (UDCA) are hepatoprotectors used in the pathogenetic therapy of liver and biliary tract. However, low bioavailability of these drugs restricts their application. In order to solve this problem, Slb and UDCA were incorporated into polymer carriers based on polylactic acid and poly(lactic-co-glycolic acid) by nanoprecipitation. The polymeric forms obtained according to the developed and optimized method are nanoparticles with a size from 100 to 200 μm. In vitro experiments showed a 1.5–2-fold higher hepatoprotective activity of Slb- and UDCA-containing polymeric nanoparticles compared to free substances.
Method for the synthesis of polymeric nanoparticles (NP) with encapsulated daunorubicin (DNR) was developed on the basis of double emulsion solvent evaporation technique using biodegradable poly(lactide-co-glycolide) (PLGA), which is aimed at customization of pharmacokinetic properties of the preparation, enhanced accumulation of DNR in tumor cells and prolongation of its action. The obtained polymer nanoparticles (DNR-PLGA) had average size ranging around 138±36 nm, with zeta-potential of –25.3 mV and the polydispersity index (PDI) of 0.072. The release kinetics of DNR from polymer nanoparticles at pH 7.4 and 5.0 has been studied. In vitro studies showed similar specific activity of DNR- PLGA in K562 and MCF-7 cancer cell lines together with an increase in activity in K562 Adr and MCF-7 Adr cell lines, which are anthracycline resistant, by 1.6 and 3.4 times. The study demonstrated the efficacy of the developed PLGA-based DNR delivery system in the improvement of antitumor effect of DNR, overcoming multidrug resistance in cancer cells, and also in the decrease in nonspecific toxicity of the preparation.
In order to study the possibility of using a metal complex of the porphyrin series, FeIIICl-tetraphenylporphyrin (FeClTPP), and its polymeric form as antitumor agents for binary catalytic therapy, the technology of preparation of polymer particles containing FeClTPP was developed for the first time. The experimental data obtained allow one to conclude that the developed form using a copolymer of lactic and glycolic acids (ratio of monomer units 50: 50), ultrasonic homogenization, D-mannitol (as a cryoprotectant), the active agent to polymer ratio 1: 10, and the organic to aqueous phase ratio 1: 10 and 1: 20, respectively, has the optimal physicochemical parameters. It was found that the free substance of FeClTPP and polymer particles with FeClTPP are active against MCF-7 (human breast adenocarcinoma), HeLa (human cervical carcinoma), and MG-63 (human osteosarcoma) cell lines. The polymer particles containing FeClTFP exhibit the highest cytotoxic effect against MCF-7 lines as compared to the free substance. The results of the study indicate that both the substance of tetraphenylporphyrin and its resulting polymeric form are promising for the treatment of tumor diseases in binary catalytic therapy.
A new pharmaceutical form of the antitumor drug docetaxel (Dtx) has been developed based on a biodegradable copolymer of lactic and glycolic acids (PLGA 50/50). This form was constituted of polymeric particles (250 to 300 nm in size) and was highly active against mouse mammary adenocarcinoma (Ca755) and human breast adenocarcinoma (MCF-7 Wt ) cell lines. The results of the in vivo studies carried out on the C 57 Bl/6 female mice line showed an increase in the life span of the animals treated with the polymeric particles. Furthermore, the polymeric drug at a dose of 10 mg/kg and the drug substance at a dose of 20 mg/kg manifested a similar effect. At the same time, the acute toxicity of the Dtx polymeric form was 2.3 times lower than that of the drug substance.
Изменение популяции стволовых клеток рака молочной железы линии MCF-7 при одиночном и комбинированном действии ионизирующего излучения и конъюгатов дендритных полимеров с доксорубициномМатчук О
Second-generation (G2) polyamidoamine (PAMAM) dendrimers are branched polymers containing 16 surface primary amine groups. Due to their structural properties, these polymers can be used as universal carriers in various drug delivery systems. Amine-terminated PAMAM dendrimers are characterized by a high positive surface charge, leading to effective but nonspecific interactions with negatively charged cell plasmatic membranes. To reduce the nonspecific internalization of PAMAM dendrimers, their primary amine groups are often modified by acetic or succinic anhydrides, polyethylene glycol derivatives and other compounds. In this work, the role of primary amine groups, which are localized on the surface of doxorubicin-conjugated (Dox) dendrimers, was studied with regard to their intracellular distribution and internalization rates using SKOV3 human ovarian adenocarcinoma cells. It was demonstrated that all Dox-labeled G2-derivatives containing different numbers of acetamide groups synthesized in this work show high rates of cellular uptake at 37°С. As expected, the conjugate carrying the maximum number of primary amine groups demonstrated the highest rates of binding and endocytosis. At the same time, the G2-Dox conjugate containing the maximum number of acetamide groups showed colocalization with LAMP2, a marker of lysosomes and late endosomes, as well as the highest level of cytotoxic activity against SKOV3 cells. We conclude that second-generation PAMAM dendrimers are characterized by varied pathways of internalization and intracellular distribution due to the number of primary amine groups on their surface and, as a consequence, a different surface charge.
The dendritic polymers (dendrimers) are perspective nanocontainers for targeted transport of anticancer drugs to tumor cells. We used polyamidoamine dendrimers of the second generation (G2) covalently conjugated with doxorubicin (Dox) and vector protein - recombinant third domain (3D) of alpha-fetoprotein. The objects of the study were MCF-7/MDR1 breast cancer cells, which demonstrated resistance to traditional anticancer agents due to high expression of P-glycoprotein. Effects of free Dox, G2 dendrimers loaded with Dox (G2-Dox), or conjugates of dendrimers with the vector protein and Dox (3D-G2-Dox) were assessed by the criteria of surviving cell number and clonogenic activity 24 hours and 11 days after treatment with the agents at Dox concentration of 2.5 mu M, correspondingly. Flow cytometry was used to evaluate accumulation of Dox immediately after the treatment with the agents and removal of Dox during 24 hours of incubation in agent-free medium following by the treatment. Intracellular localization of Dox was studied using laser scanning microscopy. 3D-G2-Dox demonstrated the highest accumulation and the weakest removal from the cells in comparison with all other agents. The use of free Dox, G2-Dox, or 3D-G2-Dox resulted in a significant decrease in number of surviving cells by approximately 25-30% compared to the control (p <= 0.01). However, the most pronounced decrease in the clonogenic ability of cells was observed in the 3D-G2-Dox group (to 19% compared to the control, p < 0.01). Taking into account the previously obtained data on the extremely low 3D-G2-Dox accumulation in normal cells, it can be concluded that further development of 3D-G2-Dox as a possible anticancer drug is a promising way to overcome multiple drug resistance with minimal impact on normal cells.
The results of many years of scientific research in the field of physico-chemical biology and its most important direction - lipidology, conducted by the leading scientific school under the leadership of Academician RAS Vitaly I. Shvets, are reported. On the creation of synthetic, biotechnological methods for obtaining lipids, with the possibility of their practical use by designing on this basis effective diagnostic and medicinal products and application in practical medicine. The further development and use of methods of bionanotechnology for the development of modern medicines for directed action on the basis of increasing the effectiveness of classical drugs by their incorporation into nanocontainers is described. It is reported on the development of technologies for obtaining nanoscale forms of drugs, the study of their pharmacological properties and use in medical practice. Information is provided on the preparation of liposomal antitumor, hepatoprotective, anti-tuberculosis, cardiac preparations based on the proposed echnologies, the study of properties and the use for therapeutic purposes. The technologies for obtaining and conducting biological studies of nanoforms based on copolymers of lactic and glycolic acids of antineoplastic, anti-inflammatory, antibacterial and a number of other drugs have been developed: It has been shown that the use of nanosized drugs can lead to a significant increase in the pharmacological effect due to various factors. It was noted that during the construction of the drug for the treatment of Parkinson's disease, the contents of liposomes loaded with dopamine pass through the blood-brain barrier almost 100 times better than individual dopamine molecules. Finding a substance in nanoparticles reduces its toxicity primarily due to the effect of "passive targeting". The prolonged action of medicinal substances enclosed in nanoparticles is discussed, due to their gradual release. It is noted that the targeted delivery of nanoparticles makes it possible to increase the effectiveness of the drugs by an order of magnitude. It is reported on the drug-delivery technology in the field of oncology and the use of the method of selective delivery of cytostatics to tumor tissues using the receptor-mediated endocytosis. Biological and pharmacological studies based on nanopoporous silicon on the creation of liposomal drugs for the treatment of cancer, cardiological pathologies, tuberculosis are carried out. Data on the work of the scientific and educational center for training specialists in the field of biotechnology and pharmacy are given.
A wide range of methods are known to increase the prokaryotic intracellular recombinant proteins solubility, for instance, growth at low temperature, supplementation of culture media with "chemical chaperones" (proline, glycine-betaine, and trehalose), co-expression with chaperones or highly soluble fusion partners. As an alternative, we have introduced the polyglutamate tag, which, as it has been shown, increased the protein solubility and facilitated folding. In this study we evaluated the minimal quantity of high density negatively charged EEEEVE amino acid repeats (pGlu) necessary to switch the recombinant receptor-binding domain of human alpha-fetoprotein (rbdAFP) expression almost entirely from the inclusion bodies to the soluble cytoplasmic fraction in E. coli. For this purpose, genetic constructs based on pET vectors coding rbdAFP and containing from 1 to 4 additional EEEEVE repeats at the C-terminus have been prepared. It was found that 3 pGlu repeats is the minimal number, that leads to a complete shift of the expression to the soluble cytoplasmic fraction in E. coli SHuffle Express T7 while 4 repeats were required for that in E. coli BL21(DE3). The rbdAFP contained 4 pGlu repeats was purified making use of ion-exchange chromatography and characterized by circular dichroism and ability to bind and accumulate in AFP receptor positive cancer cells in order to check for the structural and specific activity alterations related to the additional polyanionic sequence introduction.
Polymer particles containing carboplatin (CPt) were developed by the inclusion of this antitumor agent in a copolymer of lactic and glycolic acids (PLGA-COOH 50/50). The polymer particles were found to have a spherical form with an average diameter not exceeding 200 nm, the ζ-potential is equal to–32.2±1 mV. The CPt-loaded polymer particles possess a cytotoxic activity against human small cell and non-small cell lung carcinoma (lines H69 and A549), as well as against mouse mammary adenocarcinoma (line Ca755). The results of the in vivo studies carried out on female mice of line C57Bl/6 with inoculated mouse melanoma of line B16 showed increasing of lifespan of the animals and inhibition of tumor growth for groups treated with the polymer particles, as compared to the animals treated with the drug substance CPt.
Biocompatibility of film and fibrous scaffolds from polylactide-based polymers and the relationship between their architecture and the functional characteristics of mesenchymal stem cells were studied. Cell culturing on polylactide-based film and fibrous matrixes did not deteriorate cell morphology and their proliferation and differentiation capacities. The rate of cell proliferation and penetration in microporous 3D matrices with the same porosity parameters and pore size depended on their spatial organization. The above materials can be used as scaffolds for mesenchymal stem cells for creation of tissue engineering implants. The scaffold size and structure should be determined by the defects in the organs in which the regeneration processes have to be stimulated.
The results of many years of scientific research in the field of physico-chemical biology and its most important direction - lipidology, conducted by the leading scientific school under the leadership of Academician RAS Vitaly I. Shvets, are reported. On the creation of synthetic, biotechnological methods for obtaining lipids, with the possibility of their practical use by designing on this basis effective diagnostic and medicinal products and application in practical medicine. The further development and use of methods of bionanotechnology for the development of modern medicines for directed action on the basis of increasing the effectiveness of classical drugs by their incorporation into nanocontainers is described. It is reported on the development of technologies for obtaining nanoscale forms of drugs, the study of their pharmacological properties and use in medical practice. Information is provided on the preparation of liposomal antitumor, hepatoprotective, anti-tuberculosis, cardiac preparations based on the proposed echnologies, the study of properties and the use for therapeutic purposes. The technologies for obtaining and conducting biological studies of nanoforms based on copolymers of lactic and glycolic acids of antineoplastic, anti-inflammatory, antibacterial and a number of other drugs have been developed: It has been shown that the use of nanosized drugs can lead to a significant increase in the pharmacological effect due to various factors. It was noted that during the construction of the drug for the treatment of Parkinson's disease, the contents of liposomes loaded with dopamine pass through the blood-brain barrier almost 100 times better than individual dopamine molecules. Finding a substance in nanoparticles reduces its toxicity primarily due to the effect of "passive targeting". The prolonged action of medicinal substances enclosed in nanoparticles is discussed, due to their gradual release. It is noted that the targeted delivery of nanoparticles makes it possible to increase the effectiveness of the drugs by an order of magnitude. It is reported on the drug-delivery technology in the field of oncology and the use of the method of selective delivery of cytostatics to tumor tissues using the receptor-mediated endocytosis. Biological and pharmacological studies based on nanopoporous silicon on the creation of liposomal drugs for the treatment of cancer, cardiological pathologies, tuberculosis are carried out. Data on the work of the scientific and educational center for training specialists in the field of biotechnology and pharmacy are given.
Temozolomide (TMZ) is a cytostatic drug used in treatment of patients with malignant gliomas and melanomas. The development of innovative formulations for delivery of TMZ into target cells in order to reduce its systemic toxicity and gain prolonged effect is a topical problem of modern biotechnology and pharmacology. The article presents experimental data on development of the TMZ polymer-based formulation. The TMZ formulation presents nanoparticles with average size of 300 nm exhibiting high in vitro cytotoxic activity against melanoma and glioma cells (cell lines C6, U377MG, B16, and Mel-10). Melanoma (B16 cell line) bearing mice (C57Bl/61) treated by TMZ polymer nanoparticles revealed inhibition of tumor growth and increase of the animal lifespan. Also, loading of TMZ into the polymer particles was shown to decrease acute toxicity of the drug compared to the intact drug.
A recombinant alpha-fetoprotein (rAFP) was obtained in the yeast P. pastoris system, and its functional activity was confirmed. A method for producing polymer particles loaded with dactinomycin was developed, and a conjugate of these nanoparticles with rAFP was synthesized. The efficiency of the obtained conjugate on the HeLa, SKOV3, and MG-63 tumor cells and the absence of toxicity on the normal cells was shown. Experiments in vivo demonstrated a significant increase in the antitumor efficacy of the conjugate at a lower general toxicity as compared to the commercially available dactinomycin.