Here, two new topical hydrogel formulations (R1HG-3c and R1HG-4b), promising to treat staphylococcal skin infections, have been developed. To this end, two pyrazoles (3c and 4b) previously reported to possess antibacterial activity against multi drug resistant (MDR) staphylococci, were used as active ingredients, while a polystyrene-based cationic resin (R1) was employed as gelling agent. Particularly, we synthesized and characterized R1, which showed high hydrophilicity, high-level porosity, excellent swelling capabilities, and aptitude to form hydrogel by simple dispersion in water, thus allowing to formulate 3c and 4b as hydrogels, without using any further additive. The obtained R1HG-3c and R1HG-4b showed high equilibrium degrees of swelling (EDS) of 765% and 675%, as well as great equilibrium water contents (EWC) of 88% and 87%, respectively. Chemometric-assisted attenuated total reflectance (ATR) Fourier transform infrared (FTIR) analyses, as well as optical and scanning electronic microscopy were employed to investigate the chemical structure and morphology of both soaked and dried hydrogels. Weight loss studies helped in assessing the water release profiles of hydrogels, whose stability over 4 months was inspected by monitoring their inversion properties and by chemometric-assisted ATR-FTIR spectroscopy. By proper experiments, including amplitude and frequency sweep studies, the flow and dynamic rheological behaviour of the gels was evaluated. Finally, their content in NH₃⁺ groups deriving from R1, and known to promote the antibacterial effects, was determined by potentiometric titrations. Collectively, the favourable physicochemical characteristic of R1HG-3c and R1HG-4b, as well as the demonstrated antibacterial effects of their ingredients (3c and 4b) against MDR staphylococci, possibly further improved by the cationic R1, support the future development of our pyrazole-enriched hydrogels as new weapons to treat severe skin and wound infections sustained by MDR bacteria of Staphylococcus genus.

Antibiotic resistance is one of the most serious threats to human health, food security and development today. New resistance mechanisms are emerging and spreading everywhere, threatening our ability to treat common infectious diseases. In this work, new semi-synthetic agents were synthesized based on a derivative of the natural compound Camphor, thiosemicarbazide and 2-acetyl/2-benzoylpyridine. For this purpose, thiosemicarbazones were synthesized in two steps. At the first step the N⁴-norbornylthiosemicarbazide was dissolved in ethanol with 2-acetylpyridine/2-benzoylpyridine. Concentrated hydrochloric acid was added to the obtained solution. At the second step the obtained 2-acetylpyridine hydrochloride N⁴-norbornylthiosemicarbazone (HL¹) and 2-benzoylpyridine hydrochloride N⁴-norbornylthiosemicarbazone (HL²) were dissolved in ethanol and neutralized with an aqueous solution of Na₂CO₃. Then extraction with chloroform was done. The resulting substances were studied using FT-IR and NMR ¹H, ¹³C spectroscopy. The copper(II) coordination compounds were obtained by reaction between HL¹ or HL² and copper(II) nitrate trihydrate, copper(II) chloride dihydrate, and copper(II) dicloroacetate. The complexes [Cu(L^1,2)X] (X = NO₃^- (I, VI), Cl^- (II, V), CHCl₂COO^- (III, VI)) were studied by elemental analysis, FT-IR spectroscopy and molar conductivity. The antibacterial activity against Gram-positive microorganisms: Staphylococcus aureus and Bacillus cereus was studied for the obtained substances. The results showed that 2-benzoylpyridine N⁴-norbornylthiosemicarbazone (HL²) is inactive one, and its copper(II) coordination compounds are 8 times less active than complexes with HL¹ against Staphylococcus aureus and 32 times less active against Bacillus cereus. They in many cases surpass the activity of Furacillinum and are practically on the same level as Tetracycline, that are used in medicine.

The most effective small molecular inhibitors of TrmD with confirmed in vivo antibacterial activity contain either 3-indolyl of thieno[2,3-d]pyrimidine moiety. Recently we have reported the antimicrobial activity of the synthetically available 4-methylthieno[2,3-d]pyrimidine-6-carboxamides with benzyl substituents at the primary amide fragment as effective antimicrobials with the predicted affinity to TrmD isolated from P. aeruginosa. It was also reported that 4-oxothieno[2,3-d]pyrimidine derivatives were more effective TrmD inhibitors rather than their 4-alkoxy analogues with aromatic pyrimidine fragment. Therefore we have prepared N-(benzyl)-5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxamides as the close analogues, which turned out to be active in vitro against the strains of S. aureus and B. subtilis and only moderately active against P. aeruginosa strain. Docking studies showed that despite the good values of the scoring functions, the conformational analysis of the ligands’ poses in the active site revealed their ability for only partial inhibition of TrmD of P. aeruginosa. The study revealed better activity for N-benzyl-4,5-dimethylthieno[2,3-d]pyrimidine-6-carboxamide against P. aeruginosa in comparison to their 4-oxo analogues.

Ru(III)-based complexes are generally considered attracting antitumor drugs for their remarkable anticancer and/or antimetastatic properties combined with general low toxicity in vivo, as well-demonstrated for two iconic Ru(III) compounds, known as KP1019 and NAMI-A. Intrigued by the excellent pharmacological activity of several Ru(III)-based drugs, some years ago, we started a study on a structurally-related NAMI-A compound, named AziRu, inserting it into nucleolipidic structures. These nucleolipidic-based Ru(III) complexes were then further co-formulated with biocompatible lipids, thus forming stable liposomes featured by a significant antiproliferative activity and selectivity for cancer cells both in vitro and in vivo. With the aim of enriching the arsenal of the available Ru(III) compounds, we recently designed a set of novel Ru(III) complexes characterized by lipophilic appendages decorating the structure of AziRu. Thus, the pyridine ligand of the ruthenium ion was conjugated with selected lipids (fatty acids or a cholesterol derivative) providing different lipid-functionalized Ru(III) complexes obtained with simple and high yielding synthetic schemes. Their molecular and self-assembling properties in proper buffer solutions mimicking the extracellular environment were investigated using several biophysical techniques. In vitro biological experiments, performed on a selected panel of cancer and healthy cell lines, proved that the lipophilic compounds carrying a palmitic and a stearic acid-based tail, named PalmiPyRu and StePyRu respectively, exhibited an interesting antiproliferative activity on specific breast cancer phenotypes without showing toxicity on normal cells, used as control. These lipophilic Ru(III) complexes were thus selected for more in-depth investigations aimed at evaluating their ability to interact with potential biomacromolecular targets, such as the bovine serum albumin (BSA), as a model serum protein, and a harpin duplex and two unimolecular G-quadruplex structures, as DNA model systems. These studies, performed by spectroscopic techniques in comparison with AziRu, evidenced the unique ability of PalmiPyRu to interact with both BSA and the selected G-quadruplex structures, one from the human telomere and the other from the c-myc oncogene promoter. In addition, PalmiPyRu exhibited a 20-fold enhanced cell uptake compared to AziRu in two breast cancer cell lines of different histological origin. Overall these results indicated PalmiPyRu as the best candidate in the designed series of lipid-conjugated Ru(III) complexes with marked improved cytotoxicity and cell uptake ability than AziRu. Ongoing experiments are devoted to better understand the in vitro distribution of PalmiPyRu after its administration in cell and identify the specific cell death pathway that this candidate drug is able to activate.

The level of transduction efficiency of target retinal cells affects the choice of AAV serotype and the outcome of gene replacement therapy for inherited retinal diseases (IRDs). While AAV2 serotype was used in the first approved ocular gene therapy Luxturna, AAV2/8 and AAV2/5 capsids later demonstrated high tropism to retina cells. This study focused on tropism, efficacy and rate of viral invasion of rAAV 2.7m8, 2/5, 2/8 and 2/9 expressing GFP in ARPE-19 and HEK293 cell lines. GFP expression was assessed bi-hourly by live imaging microscopy IncuCyte S3. Within 12 hours, AAV2.7m8 demonstrated highest transduction efficiency at four viral concentrations (1×10⁴, 3×10⁴, 6×10⁴ and 8×10⁴ VG/cell) in dose-dependent manner followed by AAV2/5 in ARPE-19 and AAV2/9 in HEK293 cells. The efficiency by AAV2.7m8 at the dose of 6×10⁴ VG/cell was 20, 201 and 323 times higher in ARPE-19 cells and 324, 99 and 52 times higher in HEK293 cells than that of AAV2/5, AAV2/8 and AAV2/9, respectively. This trend remained for 4.5 days at all viral concentrations as additionally shown by flow cytometry. At the dose of 6×10⁴ VG/cell, AAV2.7m8 (63% GFP⁺ cells) was nearly 3 and 10 times as efficient as AAV2/5 (22% GFP⁺ cells) and AAV2/9 or AAV2/8 (10% and 8%), respectively, in ARPE-19 cells. Thirty-three percent of HEK293 cells transduced by AAV2.7m8 were GFP⁺, followed by AAV2/9 (10%), AAV2/8 (9%) and AAV2/5 (3%). Thus, AAV2.7m8 demonstrated itself as the most efficient delivery tool which should be utilised for such IRDs treatment as RDH12-associated retinopathy.

Steroid compounds incessantly attract attention due to their biological and clinical importance. Considering that many cancers are hormone-dependent, synthetically modified steroid molecules are suitable candidates for the treatment of these malignancies. It has been established that steroid compounds with a heterocyclic ring or heteroatoms in their structure represent potential anticancer agents, and also have other important pharmacological properties. With this in mind, we have synthesized novel 17-(pyridin-2-yl)estra-1,3,5(10),16-tetraen compounds, starting from 17β-hydoxy-17α-(pyridin-2-yl)-estra-1,3,5(10)-triene derivatives by dehydratation reactions. For all synthesized compounds we analyzed in silico ADMET properties using the online SwissADME tool and ProTox II virtual lab. Since these modified compounds are based on steroidal scaffolds, their relative binding affinities for the ligand-binding domains of estrogen receptor α and β and androgen receptor were evaluated using a fluorescent assay in yeast.

Ultra-short peptides have great promise in anticancer therapy due to their unique properties and recent progress in biotechnology that help overcome the limitations of peptides and realize their full potential. Short peptides combine the advantages of traditional small molecules and macromolecules, i.e. greater conformational rigidity, stability, bioactivity, bioavailability, tissue specificity, selectivity, permeability through cell membranes, faster biological effect, biocompatibility, biodegradability, lower toxicity, and immunogenicity, easier and cheaper for large synthesis scale. The main disadvantages of peptides include high conformational freedom, short half-life in vivo, and low bioavailability. Modulating intramolecular interactions forming pseudo-cyclic systems is an attractive approach to precisely control conformation and interaction with the appropriate receptor. These interactions increase both in vivo stability and permeability across cell membranes and into target cells. Our studies concentrate on the development of ultra-short peptides that are able to form pseudo-cyclic systems/synthons via intramolecular interactions. In addition, these systems can be stabilized by weak π-based intramolecular interactions. The interactions play a role in protecting the polar group (in this case - peptide bond). Thus, these compounds can be useful in research on molecules that can adapt the particles to the environment (molecular chameleons) - when the closed/cyclic form is preferred in an apolar environment, e.g. inside a cell membrane, and the open one - in an aqueous medium. On the poster, we will present the results of our studies on the development and characterization of these peptides in detail. We will focus on discussing the new synthons - pseudo-(bi)cyclic systems via intramolecular interactions in the rational design of a new generation of safe and effective theranostics.

Aromatase (CYP19A1) is one of the target enzymes in breast cancer fight. Several aromatase inhibitors (AIs), either steroidal or non-steroidal AI, have been discovered in recent years, nevertheless avoiding adverse effects, and overcoming resistance mechanism still remain a challenging. As a continuation of the discovery of novel anti-breast cancer drugs, a library of sulfonamide compounds able to inhibit the aromatase enzyme by the interaction with the HEME group, was designed and synthesized. The general structure of compounds is characterized by the presence of a phenyl, or a benzyl ring linked to the sulfur atom of the sulfonamide group, while the nitrogen atom is substituted with an aromatic or non-aromatic heterocycle. The one-pot synthesis is realized by the reaction between the appropriate amine and the aryl sulfonyl chloride. All compounds were tested for the enzymatic IC₅₀, cellular IC₅₀ in MCF7 breast cancer cell line, and for the evaluation of the cell viability (MTT assay). To understand the binding mode and finding out the molecular interactions responsible for the effective binding to the active site of aromatase enzyme, computational simulations were carried out using Maestro by Schrödinger. Additionally, using QikProp, the physicochemical parameters of drug candidates were calculated in order to examine their pharmacokinetic characteristics.

Pyridones constitute a significant class of heterocyclic compounds that are prevalent within natural compounds and synthetic pharmaceutical agents. In the present study, a series of seven distinctively modified 2-pyridone derivatives were investigated with the aim of elucidating their potential in mitigating neuroinflammatory responses and conferring neuroprotection. To evaluate the properties of these derivatives, lipopolysaccharide (LPS)-stimulated BV2 microglial cells were used as experimental model. The metabolic activity of the cells and the production of inflammatory mediators, including reactive oxygen species (ROS), nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) were determined. The neuroprotective effect of investigated 2-pyridone derivatives was explored using a BV2 supernatant transfer model on SH-SY5Y neuronal cells. Molecular docking studies were conducted on proteins of interest associated with the LPS-induced BV2 inflammatory pathway, with the aim of unraveling potential underlying mechanisms responsible for the observed activities. Our findings demonstrated significant anti-neuroinflammatory properties exhibited by the investigated 2-pyridone derivatives, as evidenced by their ability to suppress the production of ROS, NO, IL-6, and TNF-α by LPS-stimulated BV2 cells. Moreover, a neuroprotective effect was observed in the microglial supernatant transfer model involving SH-SY5Y neuronal cells. The molecular docking studies suggested that investigated 2-pyridone derivatives might exert their anti-neuroinflammatory actions through interactions with proteins associated with the TLR4 pathway and inducible nitric oxide synthase. In conclusion, this study indicates that investigated 2-pyridone derivatives possess the potential to alleviate neuroinflammation mediated by microglia and protect neighboring neurons from damage, qualifying them for further investigation in neurodegenerative diseases associated with neuroinflammation.

Ovarian cancer (OVC) is a current health problem for women around the world. The high mortality rate from OVC makes the development of new therapeutic drugs relevant. Ribavirin (RBV, chemical name 1,2,4-triazole-3-carboxamide) is commonly used as an antiviral agent. In recent years, research has focused on repurposing RBV as an anticancer drug. However, RBV reveals a number of side effects, so synthetic derivatives of 1,2,4-triazole-3-carboxamide (TCA) are being actively developed and tested as putative anticancer drugs. The purpose of this study is to estimate the anticancer effects of RBV, TCA and its derivatives (MGs) in vitro. Cytotoxic effect of the MGs on ovarian cancer cells (OVAR3 and OVAR4) was assessed using the MTT assay. The proliferation rate of OVC cells was assessed after 72 h of treatment RBV, ТСА and MGs cell counting with trypan blue exclusion. Distribution of cell cycle phases was evaluated using flow cytometry with PI staining. RBV and MGs induced 40% cell death in OVC cells. MGs inhibited proliferation by 50-70% in OVC cells. After 72h RBV and MGs induces S-phase stunting. Furthermore, we demonstrated an increase in the number of cells in the subG1 phase (2.5%) after treatment with MG0 and MG1, as well as in G2/M-phase (10%) after treatment with MG5. According to the results obtained, 1,2,4-triazole-3-carboxamides can inhibit proliferation and induce apoptosis in vitro. These results provide the rationale for further studies of 1,2,4-triazole-3-carboxamides like anticancer drugs.