Macrophages are a promising target for drug delivery to influence macrophage-associated processes in the body, namely due to the presence of resistant microorganisms in macrophages. In this work, a series of mannosylated carriers based on mannan, polyethylenimine (PEI) and cyclodextrin (CD) was synthesized. The molecular architecture was studied using FTIR and ¹H NMR spectroscopy. The particle size, from small 10–50 nm to large 500 nm, depending on the type of carrier, is potentially applicable for the creation of various medicinal forms: intravenous, oral and inhalation. Non-specific capture by cells with a simultaneous increase in selectivity to CD206+ macrophages was achieved. ConA was used as a model mannose receptor, binding galactosylated (CD206 non-specific) carriers with constants of the order of 10⁴ M⁻¹ and mannosylated conjugates of 10⁶–10⁷ M⁻¹. The results of such primary “ConA-screening” of ligands are in a good agreement in terms of the comparative effectiveness of the interaction of ligands with the CD206+ macrophages: non-specific (up to 10%) absorption of highly charged and small particles; weakly specific uptake of galactosylated polymers (up to 50%); and high affine capture (more than 70–80%) of the ligands with grafted trimannoside was demonstrated using the cytometry method. Double and multi-complexes of antibacterials (moxifloxacin with its adjuvants from the class of terpenoids) were proposed as enhanced forms against resistant pathogens. In vivo pharmacokinetic experiments have shown that polymeric carriers significantly improve the efficiency of the antibiotic: the half-life of moxifloxacin is increased by 2–3 times in conjugate-loaded forms, bio-distribution to the lungs in the first hours after administration of the drug is noticeably greater, and, after 4 h of observation, free moxifloxacin was practically removed from the lungs of rats. Although, in polymer systems, its content is significant—1.2 µg/g. Moreover, the importance of the covalent crosslinking carrier with mannose label was demonstrated. Thus, this paper describes experimental, scientifically based methods of targeted drug delivery to macrophages to create enhanced medicinal forms.

Bacterial infections and especially resistant strains of pathogens localized in macrophages and granulomas are intractable diseases that pose a threat to millions of people. In this paper, the theoretical and experimental foundations for solving this problem are proposed due to two key aspects. The first is the use of a three-component polymer system for delivering fluoroquinolones to macrophages due to high-affinity interaction with mannose receptors (CD206). Cytometry assay determined that 95.5% macrophage-like cells were FITC-positive after adding high-affine to CD206 trimannoside conjugate HPCD-PEI1.8-triMan, and 61.7% were FITC-positive after adding medium-affine ligand with linear mannose label HPCD-PEI1.8-Man. The second aspect is the use of adjuvants, which are synergists for antibiotics. Using FTIR and NMR spectroscopy, it was shown that molecular containers, namely mannosylated polyethyleneimines (PEIs) and cyclodextrins (CDs), load moxifloxacin (MF) with dissociation constants of the order of 10⁻⁴–10⁻⁶ M; moreover, due to prolonged release and adsorption on the cell membrane, they enhance the effect of MF. Using CLSM, it was shown that eugenol (EG) increases the penetration of doxorubicin (Dox) into cells by an order of magnitude due to the creation of defects in the bacterial wall and the inhibition of efflux proteins. Fluorescence spectroscopy showed that 0.5% EG penetrates into bacteria and inhibits efflux proteins, which makes it possible to increase the maximum concentration of the antibiotic by 60% and maintain it for several hours until the pathogens are completely neutralized. Regulation of efflux is a possible way to overcome multiple drug resistance of both pathogens and cancer cells.

Evaluation of the influence of primary and secondary aging on the manifestation of molecular and cellular hallmarks of aging is a challenging and currently unresolved issue. Our study represents the first demonstration of the distinct role of primary aging and chronic inflammation/physical inactivity – the most important drivers of secondary aging, in the regulation of transcriptomic and proteomic profiles in human skeletal muscle. To achieve this purpose, young healthy people ( n = 15), young ( n = 8) and older ( n = 37) patients with knee/hip osteoarthritis, a model to study the effect of long‐term inactivity and chronic inflammation on the vastus lateralis muscle, were included in the study. It was revealed that widespread and substantial age‐related changes in gene expression in older patients relative to young healthy people (~4000 genes regulating mitochondrial function, proteostasis, cell membrane, secretory and immune response) were related to the long‐term physical inactivity and chronic inflammation rather than primary aging. Primary aging contributed mainly to the regulation of genes (~200) encoding nuclear proteins (regulators of DNA repair, RNA processing, and transcription), mitochondrial proteins (genes encoding respiratory enzymes, mitochondrial complex assembly factors, regulators of cristae formation and mitochondrial reactive oxygen species production), as well as regulators of proteostasis. It was found that proteins associated with aging were regulated mainly at the post‐transcriptional level. The set of putative primary aging genes and their potential transcriptional regulators can be used as a resource for further targeted studies investigating the role of individual genes and related transcription factors in the emergence of a senescent cell phenotype.

Visualization of the interaction of drugs with biological cells creates new approaches to improving the bioavailability, selectivity, and effectiveness of drugs. The use of CLSM and FTIR spectroscopy to study the interactions of antibacterial drugs with latent bacterial cells localized in macrophages create prospects to solve the problems of multidrug resistance (MDR) and severe cases. Here, the mechanism of rifampicin penetration into E. coli bacterial cells was studied by tracking the changes in the characteristic peaks of cell wall components and intracellular proteins. However, the effectiveness of the drug is determined not only by penetration, but also by efflux of the drugs molecules from the bacterial cells. Here, the efflux effect was studied and visualized using FTIR spectroscopy, as well as CLSM imaging. We have shown that because of efflux inhibition, eugenol acting as an adjuvant for rifampicin showed a significant (more than three times) increase in the antibiotic penetration and the maintenance of its intracellular concentration in E. coli (up to 72 h in a concentration of more than 2 μg/mL). In addition, optical methods have been applied to study the systems containing bacteria localized inside of macrophages (model of the latent form), where the availability of bacteria for antibiotics is reduced. Polyethylenimine grafted with cyclodextrin carrying trimannoside vector molecules was developed as a drug delivery system for macrophages. Such ligands were absorbed by CD206+ macrophages by 60–70% versus 10–15% for ligands with a non-specific galactose label. Owing to presence of ligands with trimannoside vectors, the increase in antibiotic concentration inside macrophages, and thus, its accumulation into dormant bacteria, is observed. In the future, the developed FTIR+CLSM techniques would be applicable for the diagnosis of bacterial infections and the adjustment of therapy strategies.

The aim of the study was to investigate the relationship between established clinical systemic biomarkers of ageing and the development of age-associated diseases and senescent cell biomarkers at tissue and cellular levels. Thirty-eight patients (mean age 70 ± 4.9 years) who were assessed for traditional risk factors for cardiovascular diseases were included. From all patients we obtained biomaterials (peripheral blood, skin, subcutaneous fatty tissue) and isolated different cell types (peripheral blood mononuclear cells (PBMC), fibroblasts (FB) and mesenchymal stem/stromal cells (MSC)). Isolated cells were analyzed using several senescent cells biomarkers such as telomere length and telomerase activity, proliferation rate, cell cycle inhibitor expression (p16 and p21), b-galactosidase activity, gH2AX expression. CD34+ cell content in peripheral blood was determined by flow cytometry. Systemic senescent cell-associated factors (insulin-like growth factor 1 (IGF-1), fibroblast growth factor 21 (FGF-21), osteoprogerin, ferritin, soluble vascular cell adhesion molecule (VCAM-1), intercellular adhesion molecule 1 (ICAM-1)) in peripheral blood as well as senescence-associated secretory phenotype (SASP) components in MSC and FB secretome were evaluated by ELISA. Skin and adipose tissue biopsy samples were analyzed histologically to assess senescent cell markers. A strong significant association of tissue p16 expression with age (r = 0.600, p < 0.001), pulse wave velocity (PWV) (r = 0.394, p = 0.015), vascular cell adhesion molecule (VCAM-1) content (r = 0.312, p = 0.006) in the systemic blood stream and p16 mRNA level in the blood mononuclear cells (MNCs) (r = 0.380, p = 0.046) were confirmed by correlation analysis. Statistically significant correlations were found with indicators of FBs and MSCs proliferation in culture and acquisition of SASP by the cells. Thus, p16 expression in tissues correlated significantly with interleukin-6 (IL-6) (r = 0.485, p < 0.05) and monocyte chemoattractant protein type 1 (MCP-1) (r = 0.372, p < 0.05) secretion by isolated cells. The results of regression analysis confirmed that, regardless of age, the expression of p16 was associated with the proliferation of isolated cells and IL-6 within SASP. Based on these findings, two models have been proposed to predict the level of p16 expression in tissues from the levels of other markers of senescent cell accumulation determined by non-invasive methods and available in clinical practice.

Multipotent mesenchymal stromal cells (MSCs) integrate hormone and neuromediator signaling to coordinate tissue homeostasis, tissue renewal and regeneration. To facilitate the investigation of MSC biology, stable immortalized cell lines are created (e.g., commercially available ASC52telo). However, the ASC52telo cell line has an impaired adipogenic ability and a depressed response to hormones, including 5-HT, GABA, glutamate, noradrenaline, PTH and insulin compared to primary cells. This markedly reduces the potential of the ASC52telo cell line in studying the mechanisms of hormonal control of MSC’s physiology. Here, we have established a novel immortalized culture of adipose tissue-derived MSCs via forced telomerase expression after lentiviral transduction. These immortalized cell cultures demonstrate high proliferative potential (up to 40 passages), delayed senescence, as well as preserved primary culture-like functional activity (sensitivity to hormones, ability to hormonal sensitization and differentiation) and immunophenotype up to 17–26 passages. Meanwhile, primary adipose tissue-derived MSCs usually irreversibly lose their properties by 8–10 passages. Observed characteristics of reported immortalized human MSC cultures make them a feasible model for studying molecular mechanisms, which regulate the functional activities of these cells, especially when primary cultures or commercially available cell lines are not appropriate.