Sci. Pharm., Volume 92, Issue 2 (June 2024) – 7 articles

Hyaluronic acid (HA), as one of the main components of the extracellular matrix (ECM), plays an important role in the process of wound-healing and tissue-repair processes due to its unique properties and different physiological functions. HA has an ability to maintain a moist environment that promotes healing, the stimulation of growth factors and cellular constituents, and the migration of various cells essential for healing. This paper offers a review of HA use in the process of wound healing, with emphasis on hard-to-heal wounds, and examines its various applications in ophthalmology and otorhinolaryngology. It proves HA to be a versatile agent which finds its use in various fields of medicine for its antioxidant, anti-inflammatory, antibacterial properties and accelerated wound healing. Full article

The development of analytical procedures, in line with the recent regulatory requirements ICH Q2 (R2) and ICH Q14, is progressing, and it must be able to manage the entire life cycle of the methodology. This is also applicable to and especially challenging for combinations of drug substances and dosage form. A reliable and efficient, stability-indicating, MS-compatible, reverse-phase ultra-performance liquid chromatographic (UPLC^®) method was developed for the determination of carvedilol and felodipine in a combination oral dosage form. The development of the method, performed using analytical quality by design (AQbD) principles, was in line with the future regulatory requirements. Furthermore, the fixed-dose combination dosage forms are a clear solution to the polypharmacy phenomenon in the elderly population. The main factors evaluated were the mobile phase buffer, organic modifier, column, flow, and column temperature. The optimum conditions were achieved with a Waters Acquity HSS T3 (100 × 2.1 mm i.d., 1.8 µm) column at 38 °C, using ammonium acetate buffer (5 mM, pH 4.5) (Solution A) and MeOH (Solution B) as mobile phases in gradient elution (t = 0 min, 10% B; t = 1.5 min, 10% B; t = 12.0 min, 90% B; t = 13.0 min, 10% B; t = 15.5 min, 10% B) at a flow rate of 0.2 mL/min and UV Detection of 240 and 362 nm for carvedilol (CAV) and felodipine (FLP), respectively. The linearity was demonstrated over concentration ranges of 30–650 µg/mL (R² = 0.9984) (CAV) and 32–260 µg/mL (R² = 0.9996) (FLP). Forced degradation studies were performed by subjecting the samples to hydrolytic (acid and base), oxidative, and thermal stress conditions. Standard solution stability was also performed. The proposed validated method was successfully used for the quantitative analysis of bulk, stability, and fixed-dose combination dosage form samples of the desired drug product. Using the AQbD principles, it is possible to generate methodologies with improved knowledge, leading to high-quality data, lower operation costs, and minimum regulatory risk. Furthermore, this work paves the way for providing a platform of robust analytical methods for the simultaneous quantification of innovative on-demand new dose combinations. Full article

Antimicrobial resistance threatens the effective prevention and treatment of an increasingly broad spectrum of infections caused by pathogenic microorganisms. This pressing challenge has intensified the search for alternative antibiotics with new pharmacological properties. Due to the chemical synergy between the biological activity of antimicrobial peptides (AMPs) and the different modes of action, catalytic properties, and redox chemistry of metal complexes, metallopeptides have emerged in recent years as an alternative to conventional antibiotics. In the present investigation, peptide ligands conjugated with 5-carboxy-1,10-phenanthroline (Phen) were prepared by solid-phase peptide synthesis (SPPS), and the corresponding copper(II) metallopeptides, Cu-PhenKG and Cu-PhenRG (where K = lysine, R = arginine, and G = glycine), were synthesized and characterized. The antimicrobial activities of these compounds toward Gram-positive and Gram-negative bacteria, evaluated by the broth microdilution technique, indicate that the metal center in the metallopeptides increases the antimicrobial activity of the complexes against the conjugated peptide ligands. Minimum inhibitory concentration (MIC) values of 0.5 μg/mL for S. aureus with the Cu-PhenKG complex and 0.63 μg/mL for S. typhimurium with the Cu-PhenRG complex were obtained. The MIC values found for the conjugated peptides in all microorganisms tested were greater than 1.5 μg/mL. The interactions of the conjugated peptides and their metallopeptides with plasmid DNA were evaluated by agarose gel electrophoresis. Alterations on the replication machinery were also studied by polymerase chain reaction (PCR). The results indicate that the complexes interact efficiently with pBR322 DNA from E. coli, delaying the band shift. Furthermore, the resulting DNA–metallopeptide complex is not a useful template DNA because it inhibits PCR, since no PCR product was detected. Finally, molecular dynamics and molecular docking simulations were performed to better understand the interactions of the obtained compounds with DNA. The Cu-PhenRG complex shows a significantly higher number of polar interactions with DNA, suggesting a higher binding affinity with the biopolymer. Full article

Synthetically produced silicon dioxide used as a food additive exhibits nanoparticle size and shape during the early stages of manufacturing. Even when processed into food products, these nanoparticles are detected. Although processing food ingredients into nanoparticles can improve absorption rates or enhance texture, there are concerns about the specific biological effects of nanoparticles. In this study, three types of silica particles, including nanosized particles, were repetitively administered to the stomach using a gastric tube or exposed to a single injection into the submucosal layer of the stomach. Macroscopic and microscopic examinations did not reveal acute toxicity. However, when silica particles were administered to the stomach during the healing and regeneration process of gastric ulcers (induced by injecting the alkylating agent of N-Methyl-N′-Nitro-N-Nitrosoguanidine into the submucosal layer), silica particles with a diameter of 70 nm (SiNPs-70) delayed regeneration more strongly than microsized silica particles with diameters of 300 nm or 1000 nm (SiMPs-300, -1000). Furthermore, fibrosis for tissue regeneration spread throughout the entire mucosa of the stomach, resulting in hypertrophic gastritis-like symptoms. The frequency of this symptom was over 50% with SiNPs-70, 20% with SiMPs-300, and 0% with SiMPs-1000. Although the silica particles used in this study differ from actual samples found in food, the impact of particle size, particularly the effects unique to nanosize, was identified as toxicity in the stomach healing process. Full article

Coccoloba uvifera is a Mayan medicinal plant, and these leaves are used as antidiarrheal and diuretic agents. In the present work, we develop in-vitro, ex-vivo, in-vivo, and in-silico strategies to evaluate several aqueous extracts of C. uvifera leaves. In vitro tests showed that decoction extract (CuDe) presented the best yield and chlorophyll, phenol, and flavonoid content; however, CuDe showed low antioxidant activity (DPPH model). All aqueous extracts exert spasmolytic and vasorelaxant activity in a concentration-dependent manner (ex vivo), and in vivo tests showed that CuDe exerts the best antiperistaltic and diuretic effects. The in-silico analysis suggests that C. uvifera triterpenes act as a ligand of GPCR, and β-sitosterol could act as an antagonist of muscarinic acetylcholine receptor subtype 3 (m3AChR). In the context of aqueous extracts of C. uvifera, β-sitosterol and their heterosides were identified by FTIR and ¹H-NMR spectroscopy. The concerted binding of β-sitosterol and other triterpenes within the m3AChR binding site may be relevant for the induction of relaxant effects at the gastrointestinal smooth muscle level. In this context, C. uvifera is a high-value plant species that requires analytical and pharmacological studies to confirm traditional medicinal use. Full article

Considering the complex pathogenesis of Alzheimer’s disease (AD), the multitarget ligand strategy is expected to provide superior effects for the treatment of the neurological disease compared to the classic single target approach. Thus, a series of 13 novel (5e-q) pyrrole-based Schiff bases were synthesized by conventional and microwave-assisted condensations, and the compounds were evaluated for MAO-A, MAO-B and AChE inhibitory activities. The chemical structures of the newly formed molecules were elucidated by a combination of spectral methods. The obtained results confirmed the theoretical data. The majority of the title Schiff bases demonstrated good potential towards AChE at 10 μM concentrations, with the most promising compound 5m (58%) exerting a comparative effect to that of the applied standard—Donepezil. 5j and 5o selectively inhibited MAO-B by 26% and 21% (at 1 μM concentration), respectively. The compound condensed with 5-nitro-2-furaldehyde (5j) achieved the best dual MAO-B and AChE inhibitory capacities. In addition to the in vitro analysis, docking simulations targeting the active sites of AChE (PDB ID: 4EY6) and MAO-B (PDB: 2V5Z) were employed to explore the possible interactions of the most prominent dual inhibitor (5j) with the enzymes. Furthermore, in silico ADME and PAMPA-blood–brain barrier (BBB) studies were conducted. Full article

Semaglutide, a glucagon-like peptide-1 (GLP-1) receptor agonist, has gained considerable attention as a therapeutic agent for type 2 diabetes mellitus and obesity. Despite its clinical success, the precise mechanisms underlying its pharmacological effects remain incompletely understood. In this study, we employed ligand-based drug design strategies to investigate potential off-target interactions of semaglutide. Through a comprehensive in silico screening of semaglutide’s structural properties against a diverse panel of proteins, we have identified calmodulin (CaM) as a putative novel target of semaglutide. Molecular docking simulations revealed a strong interaction between semaglutide and CaM, characterized by favourable binding energies and a stable binding pose. Further molecular dynamics simulations confirmed the stability of the semaglutide–CaM complex, emphasizing the potential for a physiologically relevant interaction. In conclusion, our ligand-based drug design approach has uncovered calmodulin as a potential novel target of semaglutide. This discovery sheds light on the complex pharmacological profile of semaglutide and offers a promising direction for further research into the development of innovative therapeutic strategies for metabolic disorders. The CaM, and especially so the CaMKII, system is central in the experience of both drug- and natural-related reward. It is here hypothesized that, due to semaglutide binding, the reward pathway-based calmodulin system may be activated, and/or differently regulated. This may result in the positive semaglutide action on appetitive behaviour. Further studies are required to confirm these findings. Full article