Research Results in Pharmacology

Proteins with the HAEE tetrapeptide motif as potential targets for beta-amyloid

Fri, 26 Dec 2025 00:00:00 +0300

Introduction: Beta-amyloid (Aβ) is involved in numerous physiological and pathophysiological processes and is one of the key players in the pathogenesis of Alzheimer’s disease. Aβ interacts with the 35-HAEE-38 site of the α4 subunit of the α4β2 nicotinic acetylcholine receptor. The synthetic tetrapeptide HAEE effectively inhibits the aggregation of endogenous Aβ. HAEE specifically binds to the 11-EVHH-14 site of Aβ both in the absence and presence of zinc ions, leading to the formation of stable complexes. We hypothesized that the HAEE motif could represent a universal binding site for Aβ within the human proteome.

Materials and Methods: To test this hypothesis, a large-scale search for all amino acid sequences containing the HAEE motif in the human (Homo sapiens) proteome was performed using our in-house PepString server (http://pepstring.eimb.ru/). The conservation of the identified sites was analyzed across jawed vertebrates using BLAST. Protein localization and structural features were determined based on data from UniProt, PDB, and AlphaFold.

Results: We identified 85 proteins (including 200 isoforms) containing the HAEE motif. Of these, 26 proteins are membrane proteins, including receptors, ion channels, and transporters (e.g., CACNA1B, MRS2, SLC15A2), and 59 are intracellular proteins, mostly nuclear transcription factors (including 13 zinc finger proteins). Structural analysis revealed that the HAEE motif is often located within functionally important domains, such as cytoplasmic loops of transmembrane proteins or DNA-binding domains.

Conclusion: Given that Aβ acts as an extracellular ligand and can also penetrate various intracellular compartments, all identified proteins with the HAEE motif are considered potential physiological and pathophysiological targets for Aβ. The most promising candidates are proteins whose HAEE sites are structurally similar to that in α4β2-nAChR and/or coordinate zinc ions. These findings enhance our understanding of the molecular mechanisms of Aβ function and open new avenues for the search of therapeutic targets in AD.

Effect of hydrogel with a new acexamic acid derivative on the survival of ischemic tissue

Thu, 25 Dec 2025 00:00:00 +0300

Introduction: Prevention and correction of the consequences of local ischemia developing during various surgical interventions is a pressing issue in modern medicine.

Materials and Methods: The study was conducted on 24 Agouti viable yellow mice weighing 30-35 g. An ischemic skin flap measuring 10 x 30 mm was created on the back skin of mice with a mutation in the Agouti viable yellow gene. Immediately after the procedure, the animals were topically treated twice daily with a hydrogel containing 2-ethyl-6-methyl-3-hydroxypyridinium N-acetyl-6-aminohexanoate (2E-6M-3G-NA-6A) (5%) and reference drug, panthenol gel (10%) for 10 days. Wound healing was monitored using planimetry, microcirculation, and histomorphological and biochemical parameters.

Results: The efficacy of a hydrogel based on 2E-6M-3G-NA-6A on skin tissue reparation processes was studied in transgenic C57BL/6J mice with a dominant mutation in the Agouti yellow (Au/a) gene using an isolated pedicle skin flap model. Topical application of 5% hydrogel based on (2E-6M-3G-NA-6A) twice daily for 10 days resulted in a 1.6-fold decrease in the area of tissue necrosis compared to that in the control group without pharmacological support. On the 10^th day of the experiment, in the group of animals treated with the hydrogel based on 2E-6M-3G-NA-6A, an increase in the level of microcirculation was observed on average to 489.1 ± 29.1 perfusion units (PU) (p = 0.0001) compared to such in the group of animals without treatment – 242.3 ± 19.6 PU (p < 0.0018). Hydrogel based on 2E-6M-3G-NA-6A, when applied topically to an ischemic wound, led to an increase in the level of alkaline phosphatase on the 7^th day to values of 157.4 ± 12.7 (p < 0.0014). U/L, which is 1.8 times higher than in the control group.

Conclusion: 2E-6M-3G-NA-6A in a hydrogel dosage form is capable of stimulating wound healing in ischemic tissues to the level of non-ischemic wounds and may become a new and effective method for treating long-term non-healing wounds.

Regulation of 11β-hydroxysteroid dehydrogenase isoforms: pharmacophore search and molecular design of prospective 11β-HSD1 inhibitors

Fri, 12 Dec 2025 00:00:00 +0300

Introduction: Osteoporosis is an important medical and social public health problem in an aging or elderly society, the issue of pharmacological correction of which remains unresolved to this day.

Materials and Methods: A design of prospective 11β-HSD1 inhibitors was performed on the basis of the literature data. A virtual screening of the designed compounds was performed using pharmacophore searching (DataWarrior, Flexophore), pharmacophore alignment (PhESA), and molecular docking (Jamda). 2D protein-ligand interaction maps were generated using PoseEdit, and 3D visualizations were produced in VMD. The cytotoxicity of the compounds was assessed in HEK-293 cells across a concentration range of 8–1024 μM, with IC₅₀ values calculated in RStudio.

Results and Discussion: A comprehensive virtual screening of prospective 11β-HSD1 inhibitors was performed, incorporating pharmacophore searching, PhESA alignment, and molecular docking against the 11β-HSD1 complex (PDB: 4YYZ). Several compounds (TS-897, TS-883, TS-945, and others) demonstrated Jamda Score values comparable to or exceeding that of the native ligand, indicating strong predicted binding affinity. Additional candidates were identified based on high pharmacophore similarity (>0.95). Among the 14 proposed compounds, four (IV-81, IV-91, IV-158) exhibited no cytotoxicity in HEK-293 cells (IC₅₀ > 1024 µM). These findings support the potential of the synthesized azoloazine derivatives as novel 11β-HSD1 inhibitors for further in vitro and in vivo studies in osteoporosis therapy.

Conclusion: As a result of this work, original azoloazine derivatives have been developed for further biological testing aimed at regulating the activity of 11β-hydroxysteroid dehydrogenase isoforms (11β-HSDs) for pharmacological correction of bone remodeling and osteoreparation disorders.

First discovered effect of L-norvaline on tissue saturation and the activity of respiratory chain enzymes in ischemic and reperfusion injury of the small intestine

Sergey A. Alekhin, Elena N. Bezhina , Andrey V. Dunaev, Dmitry P. Nazarenko — Tue, 09 Dec 2025 00:00:00 +0300

Introduction: Prevention and treatment of ischemic and reperfusion injury plays an important role in correcting the pathological manifestations of acute mesenteric thrombosis. The development of effective therapy and the study of the mechanisms of pharmacological agents’ action are an important problem faced by researchers.

Materials and Methods: All studies were performed on 12 female Wistar rats weighing 250±25 g. Isolated mesenteric ischemia and reperfusion were reproduced by ligation and subsequent removal of ligatures from three segmental arteries in the ileum. The saturation and activity of respiratory enzymes were studied by hyperspectral imaging and biofluorescence.

Results and Discussion: For the first time, we investigated the effect of L-norvaline at a dose of 15 mg/kg on tissue saturation and the activity of respiratory chain enzymes in ischemic and reperfusion injury of the small intestine. The study revealed an increase in the level of tissue saturation and NADH activity against the background of L-norvaline administration during ischemia, in the absence of a significant effect on saturation during reperfusion during the restoration of NADH activity.

Conclusion: The arginase inhibitor L-norvaline has a protective effect in ischemic and reperfusion injuries of the small intestine.

Regulation of 11β-hydroxysteroid dehydrogenase isoforms – novel drug targets for osteoporosis therapy

Tue, 30 Sep 2025 00:00:00 +0300

Introduction: Osteoporosis is an significant medical and social public health problem in an aging or elderly society, the issue of pharmacological correction of which remains unresolved to this day.

Materials and Methods: The rationale for this idea stems from our previous findings on the role of 11B-HSD type 2 in bone remodeling and osteoreparation, combined with a content analysis and literature review of scientific publications from PubMed, Scopus, Cyberleninka, Google Scholar, and ResearchGate.

Results and Discussion: Current understanding of the molecular mechanisms of bone homeostasis allows for a significant shift and expansion in the paradigms for treating and preventing osteoporosis. 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is a key metabolic enzyme that catalyzes the intracellular conversion of inactive glucocorticoids into physiologically active ones. Research conducted over the past decade has shown that abnormal 11β-HSD1 activity contributes to the pathogenesis of obesity, type 2 diabetes, metabolic syndrome, and osteoporosis. The scientific challenge of regulating the activity of 11β-hydroxysteroid dehydrogenase (11β-HSD) isoforms and restoring homeostasis in the 11β-HSD1/11β-HSD2 enzymatic system is proposed to be addressed through the design and application of novel azole-based heterocyclic compounds as 11β-HSD1 inhibitors.

Conclusion: The development of azole-based heterocyclic 11β-HSD1 inhibitors is expected to yield promising drug candidates for pharmacologically correcting impaired bone remodeling and repair.

The effect of metformin on behavioral characteristics and Bdnf gene expression of old rats with sex differences

Thu, 25 Dec 2025 00:00:00 +0300

Introduction: Ageing is a key risk factor for neurodegenerative diseases, so aging heightens the urgency of developing safe geroprotectors. Metformin is a compound of significant interest owing to its ability to modulate the pathogenesis of aging and related cognitive decline. Thus, the aim of the workwas to study the effects of metformin on behavior and Bdnf gene expression in the brains of aged rats with consideration of sex differences.

Materials and Methods: The study was performed on 48 old (24 months) Wistar rats divided into groups (n=8): males and females receiving metformin (35 or 70 mg/kg/day) or saline (control) for 30 days. Anxiety (Elevated Plus maze test) and spatial memory (Water maze test) were assessed. The relative level of Bdnf gene expression was determined by real-time PCR.

Results: Metformin at a dose of 70 mg/kg exerts an anxiolytic effect in males in the Elevated Plus maze test, increasing the duration of stay in the open ”arms” of the maze by 3.5 times (p=0.0443) and reducing the time of closed ”arms” by 1.5 times (p=0.0161) compared to those in the control group. Males also showed an improvement in spatial memory after the introduction of metformin at doses of 35 and 70 mg/kg in the Water Maze test: the duration of swimming in the platform zone increased by 1.7 times (35 mg/kg, p=0.04) and 1.5 times (70 mg/kg, p=0.03), respectively, compared to such in the control group. At a dose of 35 mg/kg, metformin causes a 3-fold increase in Bdnf gene expression in males in the prefrontal cortex (p=0.047) compared to such in the control group. In females, Bdnf gene expression in the cerebellum positively correlates with spatial memory (p=0.039), which emphasizes its role in cognitive functions.

Conclusion: A 30-day metformin treatment exerted pronounced anxiolytic (70 mg/kg) and mnemotropic effects (35 and 70 mg/kg) in aged male rats, correlating with elevated prefrontal cortex Bdnf geneexpression. In females, spatial memory improvement correlated with cerebellar Bdnf gene upregulation.

Efficacy and safety profiles of monoclonal antibodies used in the therapy of Alzheimer’s disease

Mon, 24 Nov 2025 00:00:00 +0300

Introduction: Advances in molecular biology and biotechnology in recent decades have led to creation of new therapeutic strategies for Alzheimer’s disease (AD) patients. Among the emerging therapeutic approaches, monoclonal antibodies are attracting particular attention due to their ability to modulate the accumulation of amyloid plaques and tau protein in the brain, thus proposing promising pathogenetic approach. Aim: to summarize efficacy, side effects and mortality rates of monoclonal antibodies based on the results of clinical trials in comparison with conventional therapy.

Methods: All registered clinical studies related to AD treatment using monoclonal antibodies were found in ClinicalTrials.gov database. The information on adverse effects was obtained from the articles related to the third phase clinical studies, with total 21 articles included in the analysis. Data on conventional therapy were retrieved from clinical guidelines related to AD treatment.

Results: We found that the number of significant side effects and mortality varies significantly for different monoclonal antibodies. For the most part, side effects are not specific to the drugs used, and therefore it is not possible to assess the direct effect of the drug on the development of certain adverse events, as well as to adequately compare the safety of different drugs, due to different mechanisms of action and recommended doses. Magnetic resonance imaging with estimation of amyloid-related imaging abnormalities changes is the most promising method for antibodies comparison, but this approach still lacks correlation with clinical course. Also, it is recommended to separately consider the side effects associated with infusion.

Conclusion: The use of pathogenetic antibody therapy will improve the quality of AD treatment in the future. However, up to date, there are no unified protocols for estimation of drug effectiveness and its comparison. Evaluation of side effects and determination of antibody-specific side effects is necessary to improve the safety of treatment of patients with AD.

Current concepts of pathogenesis of depressive disorder: A literature review

Alexander A. Spasov, Dmitriy V. Maltsev, Maria O. Maltseva — Fri, 26 Dec 2025 00:00:00 +0300

Introduction: Despite the high prevalence of depressive disorders, the pathogenesis of depression has not been fully established. Recently, a significant number of works have been published demonstrating mechanisms of development of this pathology that differ from classic monoaminergic theory. In-depth study of such mechanisms can be used as new approaches to the design of more advanced antidepressant drugs.

Materials and Methods: A search of literary sources was conducted in Google Scholar, PubMed and Cochrane databases using keywords in English: “pathogenesis of depression”, “major depressive disorder”, “β-arrestin”, “glutamate depression”, “GABA and depression”, and “neuroinflammation”. The exclusion criteria were sources published earlier than 2015. At the first step, 127 sources were chosen, but after excluding papers containing duplicated or not up-to-date information, only 40 articles were included in the review. The obtained data were briefly summarized in the form of a review article.

Results and Discussion: Translational MRI data indicate that hippocampal volume loss in depression is likely due to a disruption in serotonin-dependent neuroplasticity, which is reversible with SSRI treatment. It is believed that the therapeutic effect of these drugs is not due to a direct effect on symptoms, but rather to a restructuring of neuronal energy metabolism due to increased serotonin levels, which initiates restorative processes in the brain. β-arrestin pathway is alternative to classic in G-proteins, and some data suggest that β-arrestin-2 expression is exactly the key component of fluoxetine’s mechanism of action. Current research reveals structural, functional, and neurochemical abnormalities in GABA- and glutamate-dependent neurons that can lead to impaired signaling in the cerebral cortex and hippocampus. According to current concepts, the molecular mechanisms of these changes are associated with stress-induced excitotoxic effects, occurring against a background of elevated levels of adrenal glucocorticoids and inflammatory cytokines. Current data confirm the key role of neuroinflammation in the development of depression. Animal models of depression consistently show elevated levels of proinflammatory cytokines (IL-1β, IL-6, TNF-α). Multiple psychosocial stressors have been shown to accelerate the development of neuroinflammation, which, in turn, contributes to the progression of major depressive disorder.

Conclusion: Despite a significant amount of research in this area, the role of additional factors in the pathogenesis of depression continues to be actively explored. Established pathogenetic models do not fully explain the disorder’s clinical heterogeneity, and current research focuses on clarifying the contribution of less studied elements, including immune dysfunction, oxidative stress, and the complex interactions between various neurotransmitter systems that go beyond the classical monoamine hypothesis.

Anti-anxiety properties of new 5H-2,3-benzodiazepine and 5H-[1,2,5]triazepine derivatives

Wed, 10 Dec 2025 00:00:00 +0300

Introduction: Previous studies have examined the anxiolytic properties of compounds containing mutually annulated systems of 5H-2,3-benzodiazepine and [1,2,4]triazole, namely 7H-[1,2,4]triazolo[3,4-a][2,3]benzodiazepine derivatives. In the present work, another group of 5H-2,3-benzodiazepine and 5H-[1,2,5]triazepine derivatives was examined for psychotropic activity.

Materials and Methods: For in silico assay the PASS online test system and ADMET analysis were used. Compounds under study were also tested in vivo in Elevated Plus Maze, Open Field and Rotarod tests.

Results and Discussion: Of note is that the presence of a 3,4-dimethoxyphenyl substituent at position 4 of the diazepine ring (RD-1, RD-7) leads to a decrease in anxiolytic activity compared to 4-methoxyphenyl derivatives (RD-6, RD-9). Among the derivatives of condensed 5H-[1,2,5]triazepines, a more pronounced anti-anxiety effect was exerted by compound RD-8 with an annelated benzimidazole bicycle compared to its analog RD-15 with a pyrrole cycle. The high anxiolytic activity of the compounds is facilitated by the presence of slightly branched (RD-6, RD-9) or unbranched (RD-8) substituents in position 4 of the diazepine or triazepine cycle. In the Rotarod test, it was noted that 4-(3,4-dimethoxyphenyl)-1-hydrazino-5H-2,3-benzodiazepine (RD-1) and 4-hydrazino-7,8,9-trimethyl-1-phenyl-5H-pyrrolo[2,1-d][1,2,5]triazepine (RD-15) have a negative effect on muscle tone in mice due to the presence of a hydrazino group in their composition. According to ADMET analysis, compounds RD-6, RD-8 and RD-9 are low toxic; however, a specific toxicity study among these derivatives is recommended.

Conclusion: The most active and safe compound for further studies among the studied derivatives with a single administration is 1,4-diphenyl-5H-[1,2,5]triazepino[5,4-a]benzimidazole (RD-8) at a dose of 1.3 mg/kg.

Semaglutide reduces hypothalamic glial cell damage in a streptozocin-induced model of Alzheimer's disease

Fri, 12 Dec 2025 00:00:00 +0300

Introduction: Reactive changes in glial cells, as well as their dysfunction, particularly cerebrospinal fluid dynamics disturbances, are associated with multiple neurodegenerative diseases and Alzheimer’s disease (AD). Intraventricular administration of streptozotocin (STZ) is considered a model of sporadic AD, though data on hypothalamic glial cell changes, ependymal glia, and tanycytes in this model remain limited. Of particular interest is the potential for glucagon-like peptide-1 (GLP-1) receptor agonists to address STZ-induced changes following intraventricular administration.

Material and Methods: Using immunomorphological methods, this study assessed changes in staining density and distribution of glial proteins (GFAP, aquaporine-4, connexin 43, vimentin) and neuronal alterations in hypothalamic structures following intraventricular STZ administration (3 mg/kg) and course treatment with intraperitoneal semaglutide (0.1 mg/kg, 16 injections).

Results: STZ caused neuronal damage in the ventromedial hypothalamic nucleus, disrupted the ependymal lining and tanycytes of the third ventricle, induced reactive astrogliosis, and altered the distribution of aquaporin-4 and connexin-43. Semaglutide administration reduced astroglial activation, normalized aquaporin and connexin distribution, decreased neuronal death, and suppressed caspase-3 activation in the ventromedial hypothalamic nucleus.

Conclusion: Intraventricular single-dose STZ administration causes long-term impairment of glial functions related to cerebrospinal fluid exchange. The course treatment GLP-1R agonist semaglutide (started 5 days after streptozocin administration, 16 injections every other day) demonstrated normalizing effects on both glial and neuronal parameters in the STZ-induced AD model.