Research Results in Pharmacology

From PDC to integral quantitative metrics: an innovative approach to assessing adherence to combination pharmacotherapy in outpatient practice

Sergey B. Fitilev — 2026-05-29

Introduction: Current methods for assessing adherence to combination therapy based on aggregated measures (e.g., PDC, proportion of days covered) poorly capture treatment intensity and sustainability over time. We attempted to describe adherence trajectories for combination therapy using integral metrics. Aim: To develop a set of integral metrics analogous to key pharmacokinetic (PK) parameters – area under the concentration-time curve (AUC, area under the curve), maximum concentration (C_max), and time to maximum concentration (T_max) – to assess adherence to combination therapy as time-based exposure on the PDC methodology among outpatients.

Materials and Methods: As a specific example and a substrate for method development, we used results from a retrospective pharmacoepidemiologic cohort study of patients with heart failure (HF) who had experienced an acute myocardial infarction. Data were extracted from the Unified Medical Information and Analytical System of Moscow (Russia). Three patients with a follow-up duration of ≥24 months were randomly selected. We analyzed benefit-covered electronic prescription fills for key HF therapy classes and calculated adherence for each class using PDC across four half-year intervals. We constructed a stepwise trajectory of combination therapy as the function N(t), where N is the number of therapy classes for which the patient was covered at a given time point based on dispensed supply (accounting for days’ supply and overlaps), and t is follow-up time. By analogy with the “concentration-time” curve, we considered N(t) as a dynamic “therapy class coverage curve” and used it to calculate PK-analog adherence metrics: exposure to actually dispensed combination therapy, AUC_N(t)(class-months); normalized AUC_norm(0-1); C_maxN(t) (number of classes); and T_maxN(t) (months). In addition, we set a target threshold of N(t)≥3, determined the time to first attainment, T_optN(t), and calculated the time (or proportion of time) with N(t)≥k, denoted as T_N(t)≥k. We also quantified therapy “losses” between intervals based on a decrease in the modal value of N(t) and failure to reach the threshold over the follow-up period.

Results: AUC_N(t) values were 26.0, 87.37, and 36.67 class-months, and AUC_norm values were 0.27, 0.74, and 0.39 in patients with internal IDs 13, 39, and 110, respectively. The proportion of time with N(t)≥3 was 0.079, 0.96, and 0.23 (1.9, 22.9, and 5.5 months), and the modal N(t) values by half-year corresponded to patterns of 2→0, 3→3→4→4, and 3→2→1→0. The numeric profiles were consistent with the stepwise N(t) trajectories and reflected three distinct adherence patterns.

Conclusion: The proposed PK-associated approach enabled quantification of complex adherence trajectories for combination therapy in HF by representing them as an interpretable set of integral numeric metrics. These metrics characterize time-based exposure to combination therapy while accounting for adherence. The results support the conceptual validity of the method and may serve as a basis for further studies of its prognostic value.

Effect of solid herbal extract of Primula veris L. on the psychoemotional state of rats after chronic alcohol intoxication

Margarita V. Kustova — 2026-06-22

Introduction: The aim of the study was the effect of solid herbal extract of Primula veris L. and comparison drugs phenotropil and mildronate on the psycho-emotional state of rats after chronic alcohol intoxication (CAI).

Materials and Methods: CAI was modeled by replacing drinking water with a 10% solution of ethyl alcohol with sucrose (50 g/L) for 6 months. After alcoholization, rats at the age of 16 months were divided into the following groups: 1 – intact – animals without CAI received oral 0.9% sodium chloride solution for 14 days; 2 – control – rats after ethanol withdrawal, which were injected with a 0.9% sodium chloride solution in a similar regimen; 3, 4 and 5 – experimental – females after CAI received oral solid herbal extract of Primula veris L. at a dose of 30 mg/kg, phenotropil 25 mg/kg, mildronate 50 mg/kg, respectively. After the end of treatment, to assess the psycho-emotional state of the animals, the Open field test, Elevated plus maze test, Marble burying test and Porsolt forced swim test were performed.

Results and Discussion: In animals after CAI, increased anxiety is observed, which manifested itself in a greater number of stands with support, urinations and boluses in the Open field test compared to the intact group. In the Elevated plus maze test, the trend remained the same: rats in the control group entered the open compartment installation less often, hung from it less often, and spent less time in the open compartment. In addition, females after CAI exhibited compulsive behavior in the Marble burying test. In the Porsolt forced swim test, animals in the control group had a shorter period of active swimming compared to intact females and a longer period of immobilization, which indicates depressive behavior in the former. Solid herbal extract of Primula veris L., phenotropil and mildronate contributed to the improvement of the psycho-emotional state of animals after CAI.

Conclusion: Thus, solid herbal extract of Primula veris L. at a dose of 30 mg/kg, which was administered orally once a day to female rats for 14 days after the withdrawal of ethanol, has a pronounced anxiolytic and antidepressant effect, while phenotropil and mildronate (25 mg/kg and 50 mg/kg, respectively, in a similar regimen) had a greater anticompulsive effect.

In silico exploring the mechanisms of action of diterpenoids from Rabdosia serra against lung cancer through inhibition of the anti-apoptotic pathway

Hung Duc Nguyen — 2026-06-11

Introduction: Apoptosis resistance in non-small cell lung cancer is frequently sustained by pro-survival Bcl-2 family proteins such as Mcl-1, motivating the search for new Mcl-1 inhibitors from natural products, including diterpenoids from Rabdosia serra.

Materials and Methods: An integrated in silico approach was applied to evaluate R. serra diterpenoids as putative Mcl-1 (PDB: 6QFQ) inhibitors, integrating molecular docking, molecular dynamics simulation, MM/GBSA rescoring, pkCSM-based ADMET prediction, and DFT calculations at the B3LYP/6-31G(d,p) level, with Tivantinib as the reference ligand.

Results and Discussion: Docking prioritized CPD1 (-10.31 kcal/mol) over Tivantinib (-9.09 kcal/mol). Molecular dynamics simulation indicated stable complexes, with CPD1-6QFQ showing a more compact, less solvent-exposed ensemble (Rg 1.42-1.45 nm; SASA 83-89 nm²; RMSD 0.09-0.15 nm). MM/GBSA favored CPD1 (ΔTOTAL -26.17 ± 2.79 kcal/mol) versus Tivantinib (-24.25 ± 4.50 kcal/mol). ADMET predicted high intestinal absorption for CPD1 (98.243%), a higher unbound fraction, and fewer liabilities (negative hepatotoxicity; negative hERG II inhibition). DFT supported CPD1 with a smaller ΔE (3.7165 eV) and higher softness (0.5381 eV⁻¹) than Tivantinib.

Conclusion: Convergent computational evidence nominates CPD1 as a leading putative Mcl-1 inhibitor for optimization, while target engagement, efficacy, and safety require experimental validation.

Morphometric visualization, analysis, and assessment of atherosclerotic lesions in an apolipoprotein E–deficient mouse model (ApoE−/−)

Petr R. Lebedev — 2026-03-19

Introduction: The improvement of diagnostic methods in atherosclerosis is aimed at accurately determining the stage of the pathological process and eliminating subjective interpretation of data. Implementation of this approach increases the reliability of comparative assessment of the effectiveness of therapeutic and interventional strategies and reduces statistical variability within experimental studies.

Materials and Methods: The study was performed on 20 male ApoE−/− mice (40 weeks old) divided into groups receiving a standard diet or a Western diet. After anesthesia, PBS perfusion was performed; the heart with the aorta was excised and fixed in 10% formalin; the aorta was cleaned and stained with Oil Red O. The aorta was longitudinally opened, photographed (GelDoc), and quantitatively analyzed using a Python script. Data are presented as mean ± SD; statistical significance was assessed using Student’s t-test at p < 0.05.

Results and Discussion: Thus, the use of the Oil Red O staining method in combination with automated image analysis in Python enables a transition from subjective assessment to precise quantitative measurement of the area of atherosclerotic lesions. This approach increases the reliability of screening therapeutic interventions in experimental models and enhances the statistical power of the study.

Conclusion: In this study, an original approach to morphometric visualization, analysis, and quantitative assessment of atherosclerotic lesions of the vascular wall in an apolipoprotein E–deficient mouse model (ApoE−/−) is proposed and validated for the first time.

Evaluation of pharmacological correction of hypoxic-ischemic encephalopathy sequelae using peptide erythropoietin analogs in a mouse model of mild and moderate hypoxic-ischemic encephalopathy during the late remodeling phase

Vladimir M. Pokrovsky — 2026-03-19

Introduction: Hypoxic-ischemic encephalopathy (HIE) is an early-life brain injury that remains a leading cause of long-term neurodevelopmental deficits, including cerebral palsy, epilepsy, and cognitive-behavioral impairment. Because persistent neuroinflammation and progressive neurodegeneration contribute to delayed outcomes, targeting EPOR-CD131 with nonerythropoietic erythropoietin derivatives represents a promising strategy to modulate neurovascular unit function and limit secondary injury beyond the acute therapeutic window.

Materials and Methods: CD-1 mice underwent neonatal hypoxia–ischemia at postnatal day 9 (modified Rice–Vannucci) and were stratified 3 h later into mild or moderate injury using laser speckle imaging (RFLSI-ZW), then allocated to treatment groups. Starting on day 7 post-injury, EPO (5000 IU/kg) and Epobis (20 mg/kg) were administered subcutaneously once daily and Ara-290 (30 µg/kg) intraperitoneally twice daily for 7 days, after which exploratory behavior and caffeine-induced neurostimulation responses were evaluated.

Results: In this experimental study, Epobis and Ara-290 normalized mild HIE hyperlocomotion in the open field, whereas EPO mainly improved anxiety-like behavior and only Epobis increased peripheral time toward intact levels. In the caffeine challenge, all treatments reversed paradoxical suppression in mild HIE, and Epobis most effectively reduced caffeine-induced hyperreactivity and restored baseline activity in moderate HIE.

Conclusion: Epobis and Ara-290 normalized mild HIE hyperlocomotion in the open field, whereas Epobis provided the most comprehensive behavioral correction and EPO mainly improved anxiety-related measures. All treatments restored a physiological caffeine response in mild HIE, and Epobis most effectively improved behavior and reduced caffeine-induced hyperreactivity in moderate HIE, supporting further preclinical and subsequent clinical evaluation.

Modeling of cisplatin-induced acute kidney injury and its correction using polydatin

Aleksandr S. Netrebenko — 2026-05-31

Introduction: Cisplatin is a key drug used for anticancer therapy. However, its use is often accompanied by the development of acute kidney injury. The aim of this study was to develop an optimal model of cisplatin-induced kidney injury in rats and use it to study the nephroprotective properties of polydatin.

Materials and Methods. The experiment was performed in 100 male Wistar rats. To test the cisplatin-induced acute kidney injury model, seven groups (n=10) were formed. Animals were administered cisplatin intraperitoneally at doses of 1 mg/kg, 5 mg/kg, 10 mg/kg, and 20 mg/kg once or twice on days 1 and 8. Nephrotoxicity was corrected using polydatinat doses of 4 mg/kg and 12 mg/kg. Alpha-tocopherol acetate at a dose of 75 mg/kg was used as a reference drug. The test drug and the reference drug were administered intragastrically daily for 14 days. Nephroprotection was assessed based on the following parameters: creatinine, urea, potassium and sodium ions in the blood serum, glomerular filtration rate, fractional sodium extraction, and renal parenchyma microcirculation.

Results and Discussion. The optimal model of cisplatin-induced acute kidney injury was the one in which cisplatin was administered at a dose of 5 mg/kg on days 1 and 8 of the experiment. This was evidenced by an increase in creatinine level to 124.0 ± 8.6 μmol/L and urea to 20.3 ± 1.2 mmol/L, a decrease in glomerular filtration rate to 0.08 ± 0.01 mL/minand a 2-fold deterioration in microcirculation. Other models were significantly inferior in representativeness. Polydatindemonstrated dose-dependent nephroprotective properties, which was confirmed by improvement in laboratory and instrumental parameters.

Conclusions. The use of cisplatin at a dose of 5 mg/kg intraperitoneally on days 1 and 8 results in optimal modeling of cisplatin-induced acute kidney injury in rats in the experiment. The potential of intragastric use of polydatin for nephroprotection in cisplatin-induced acute kidney injury has been proven in dosages of 4 mg/kg and 12 mg/kg per day for 14 days.

Evaluation of the neuroprotective effects of synthetic erythropoietin derivatives in a mouse model of mild and moderate hypoxic-ischemic encephalopathy

Mikhail V. Korokin — 2026-03-17

Introduction: Hypoxic-ischemic encephalopathy (HIE) is a leading cause of neonatal brain injury and long-term neurodevelopmental impairment, and current therapies only partially prevent adverse outcomes. Although recombinanterythropoietin is neuroprotective via EPOR–CD131 (βcR), its use is limited by hematopoietic side effects, motivating evaluation of non-hematopoietic peptide analogs such as Ara-290 and Epobis in HIE.

Materials and Methods: Neonatal hypoxia-ischemia was induced in 9-day-old CD-1 mice (n = 204) using a modified Rice–Vannucci model, and animals were stratified into mild and moderate severity groups 3 hours later by laser speckle contrast imaging (RFLSI-ZW) before assignment to treatment. EPO (5000 IU/kg) and Epobis (20 mg/kg) were administered subcutaneously every 24 hours and Ara-290 (30 µg/kg) intraperitoneally every 12 hours for 7 days, after which motor-coordination performance, macroscopic lesion volume, and expression of IL-4, IL-1b, IL-6, and TNF-α were assessed.

Results: In both mild and moderate HIE, Epobis provided the most consistent neuroprotection, improving motor performance and neurological outcomes and being the only treatment to significantly reduce macroscopic lesion volume. EPO produced moderate functional benefits, whereas Ara-290 showed a less stable efficacy profile, with limited or absent effects in several behavioral and morphological endpoints.

Conclusion: In mild HIE, Epobis showed the strongest neuroprotection, improving motor-coordination performance, reducing neurological deficits, and producing the greatest reduction in macroscopic lesion volume, whereas EPO and Ara-290 had only moderate effects. In moderate HIE, Epobis and EPO most consistently improved motor outcomes, but only Epobis significantly reduced lesion volume and neurological symptom severity and produced the most pronounced immunomodulation.

Topical control of wound healing by nanocerium in carcinogenesis

Ekaterina V. Blinova — 2026-06-22

Introduction: Skin wound healing in cancer patients is a complex issue, influenced by both the tumor process itself and the effects of antitumor therapy. This study assessed the efficacy of various skin wound treatment regimens in mice with transplanted Lewis lung carcinoma (LLC).

Materials and Methods: 72 C57BL/6 mice were divided into six groups, including control, topical application of 1% cerium nanoparticles colloidal solution, 5% dexpanthenol spray, 100 mg/kg cyclophosphamide solution, and a combination of these.

Results and Discussion: It was found that topical application of cerium nanoparticles without chemotherapeutic treatment significantly shortened the time of wound regeneration to 16.5±1.0 days (p≤0.05) and reduces a postoperative scar (6±0.3 mm², p≤ 0.0001). Systemic chemotherapy treatment increased the healing time (22.5±1.0 days) and scar area (55.0±0.7 mm²), while reducing a tumor volume by 34% comparing to such in the control group. Combination therapy by dexpanthenol and cyclophosphamide promoted an antitumor effect and accelerated a tissue repair (16.3 ± 0.8 days). At the same time, local application of cerium nanoparticles did not alter regeneration (21.5 ± 1.0 days); however, the scar area was smaller (10.0 ± 0.7 mm²). Histological analysis revealed that the highest vascular density and maturity of granulation tissue in a wound were observed when treated cerium nanoparticles, while epithelial cell proliferation was reduced by cyclophosphamide.

Conclusion: The obtained data indicate the potential of topical application daily for 7 days of 1% nanocerium to accelerate wound regeneration in cancer patients without chemotherapy, and 5% dexpanthenol to accelerate skin regeneration in cancer patients receiving chemotherapy.

Neuroprotective effects of tryptanthrin in the rat model of transient focal cerebral ischemia

Mark B. Plotnikov — 2026-06-11

Introduction: The inflammatory response to cerebral ischemia plays a crucial role in stroke outcome. This study focuses on the neuroprotective effects of tryptanthrin, a plant alkaloid with anti-inflammatory activity, in the rat model of focal cerebral ischemia (FCI).

Materials and Methods: The neurological status of animals was assessed at 4, 24, and 48 hours after FCI (1-hour occlusion of the left middle cerebral artery) in male Wistar rats; the infarct size was assessed 48 hours after reperfusion. Rats received intraperitoneal injections of 6 and 12 mg/kg tryptanthrin or vehicle (control group) 30 min and 23 and 47 hours after FCI. The effects of 12 mg/kg tryptanthrin on the IL-1β and TNFα levels in brain tissue, blood brain barrier (BBB) permeability, and cerebral edema were assessed 24 hours after FCI.

Results: Tryptanthrin administration at a dose of 12 mg/kg significantly reduced the neurological deficit and infarct size compared with the corresponding values in control rats. Tryptanthrin administration at a dose of 6 mg/kg was ineffective. The IL-1β and TNF-α levels in cerebral infarction focus, the Evans blue content in the left (affected) hemisphere, and water content in the supra- and subventricular structures of the affected hemisphere increased 24 hours after FCI. Tryptanthrin administration (12 mg/kg) significantly attenuated the TNF-α level in the cerebral infarction site. The values of BBB permeability and water content in the experimental group did not significantly differ from the corresponding values in sham-operated rats.

Conclusion: Obtained data suggested that tryptanthrin may be considered an agent with significant neuroprotective properties, which provides rationale for further studies of this compound as a potential neuroprotector with anti-inflammatory mechanism of action.

Correction by neuroglutam and succicard of age-associated impairments in accelerated aging in rats with diabetes

Alexandr A. Pokhlebin — 2026-03-30

Introduction: The study aimed to investigate the impact of a long-term diabetic state on the development of accelerated aging and to evaluate the efficacy of therapy with metformin, neuroglutam, and succicard in correcting associated metabolic, behavioral, and molecular impairments.

Materials and Methods: A diabetes model was induced in rats by combined administration of streptozotocin (50 mg/kg) and nicotinamide (110 mg/kg). The total number of animals involved in the experiment was 50 individuals (25 males, 25 females). The animals were divided into 5 groups: intact, control (diabetic), and groups receiving a 4-week course of metformin (400 mg/kg), neuroglutam (26 mg/kg), or succicard (50 mg/kg). A comprehensive assessment was performed, including behavioral tests (open field, elevated cross maze, novel object recognition, forced swimming with a load, rotarod), metabolic status (oral glucose tolerance test, OGTT), and Klotho protein levels (ELISA).

Results: Diabetes induced anxiety-like behavior, cognitive decline, impaired motor coordination, and a significant decrease in Klotho protein levels. Therapy with metformin and succicardsignificantly increased Klotho protein levels and improved metabolic parameters. Neuroglutam exhibited pronounced nootropic and antidepressant-like effects. All drugs demonstrated differential effects on various aspects of behavioral activity.

Conclusion: The study demonstrates the potential of using metformin (400 mg/kg), neuroglutam (26 mg/kg), and succicard (50 mg/kg) to correct the manifestations of accelerated aging in diabetic rats with daily administration for 4 weeks. Metformin and succicard showed the most pronounced geroprotective potential. The results justify further investigation of combination therapy for correcting age-associated impairments.