Dmitry A. Svarovsky

BACKGROUND: The search for diagnostic markers reflecting muscle function, protein catabolism, and adipose tissue metabolism in sarcopenia is an important medical problem. AIM: To assess the levels of asprosin (adipokine), meteorinlike protein (myokine), and proteinaseinhibitory activity in blood plasma, and their relationship with metabolic parameters and sarcopenia criteria in sarcopenic obesity and during the presarcopenic phase. METHODS: The study included 50 participants (38 women, 12 men) aged 45–85 years. Of these, 11 had sarcopenia (reduced strength and mass), 16 had presarcopenia (reduced strength), and 23 served as controls (no strength or mass loss). We measured asprosin, meteorinlike protein, elastase and trypsinlike proteinase activity, and alpha1proteinase inhibitor in plasma. RESULTS: In sarcopenic obesity, asprosin correlated positively with fat mass (rs = 0.73, p = 0.012) and negatively with muscle strength (rs = −0.81, p = 0.023). Asprosin was higher in sarcopenia without obesity than in sarcopenic obesity: 9.200 (8.500; 9.300) vs 7.100 (6.000; 7.900) ng/mL (p = 0.045). Meteorinlike protein exceeded the upper reference limit (179–1990 pg/mL) in 50% of controls (up to 2191–2871 pg/mL) and 25% of presarcopenic participants (up to 2275–4647 pg/mL). In sarcopenic obesity, meteorinlike protein correlated negatively with Cpeptide (rs = −0.74, p = 0.005) and HOMAIR (rs = −0.79, p = 0.011). In controls, meteorinlike protein was lower in hypertensive participants, while both meteorinlike protein and asprosin were lower in type 2 diabetes. Proteinaseinhibitor imbalance in presarcopenia included increased trypsinlike activity (1.5fold) and decreased elastaselike activity (23%). Trypsinlike activity correlated with SARCF score (rs = 0.69, p = 0.02) and reduced performance. Higher alpha1proteinase inhibitor was associated with lower strength (rs = −0.62, p = 0.03) and muscle mass (rs = −0.63, p = 0.04) in controls, and with slower gait speed (rs = −0.9, p = 0.02) in presarcopenic obese participants. CONCLUSION: Adipomyokine dysfunction and plasma proteinaseinhibitor imbalance, combined with metabolic disturbances, may play a role in the development of sarcopenic obesity.

This review demonstrates that the diagnostic and prognostic significance of glial fibrillary acidic protein (GFAP) is not limited to its use as a marker of astrocytic damage but should also be considered in the context of the diversity of GFAP isoforms, their heterogeneous tissue-specific expression and their pronounced association with extracellular vesicles (EVs). The data presented in this review indicate that GFAP-positive (GFAP+) EVs possess broad clinical relevance in both acute and chronic pathologies of the nervous system, including ischemic stroke, traumatic brain injury, glioblastoma, and potentially diabetic and drug-induced polyneuropathy. Particular attention is given to the critical analysis of methodological approaches for studying GFAP+ EVs, including discussion of their proposed biogenesis, mechanisms of intravesicular incorporation of cytoskeletal fragments, and the hypothetical sorption of GFAP within the vesicular protein corona. A principal conclusion of this work is that, despite the high translational potential of GFAP+ vesicles as a novel liquid biopsy platform, further implementation of this approach in clinical practice will require standardization of EV isolation protocols, harmonization of phenotyping methodologies in accordance with MISEV 2023 recommendations, and large-scale prospective studies aimed at validating the biological nature, origin, and clinical reproducibility of identified GFAP-associated vesicular subpopulations.

The study of plasma levels of matrix metalloproteinases (MMPs) and their inhibitor (TIMP-1) in patients with sarcopenia of varying severity, taking into account metabolic disorders and sarcopenic obesity has been conducted. In this study, sarcopenia was accompanied by sarcopenic obesity in 75% of cases. The level of the total MMP2 pool in extracellular vesicles was increased in the group of patients with isolated sarcopenia (p<0.05), whereas in patients with sarcopenic obesity, the concentration of the total MMP2 pool remained stable. Furthermore, the level of MMP2+9+TIMP- was elevated in patients with presarcopenia. As the disease progressed, the content of MMP2+9+TIMP- in exosomes decreased in the group of patients with sarcopenic obesity. In the sarcopenic obesity subgroup, patients showed a statistically significant increase in C-peptide levels (p=0.01). It was found that obesity and hyperglycemia associated with insulin resistance influence the redistribution of matrix metalloproteinases. Specifically, a decrease in the level of MMP9+2+TIMP- exosomes was revealed during the transition from presarcopenia to sarcopenia in patients with sarcopenic obesity.

Objective: The objective of this study was to choose the optimal anesthesia method for gastric cancer patients undergoing surgery with lymph node dissection. Materials and Methods: The study included 53 patients with stage T1-4aN0-3M0 gastric cancer, who underwent radical surgery with xenon and dexmedetomidine (DMM) anesthesia in combination with epidural analgesia (main group, 27 patients) or with sevorflurane anesthesia in combination with epidural analgesia (comparison group, 26 patients). All patients underwent monitoring of hemodynamic parameters, blood coagulation system, thromboelastometry, and inflammation and metabolic parameters (interleukins, hormones and glucose levels), with an assessment of complications according to the Clavien-Dindo classification and the intensity of postoperative pain. Results: Awakening and extubation times, narcotic analgesic consumption, and Numeric Rating Scale pain scores were lower in the xenon + DMM group than in the sevoflurane group (p < 0.05). The overall number of patients experiencing complications did not differ significantly between anesthesia types; however, significant differences were found in the total number of complications (p = 0.003), the number of complications according to Clavien-Dindo I (p = 0.043) and II (p = 0.019), and the incidence of postoperative nausea and vomiting (p = 0.042). Conclusions: The BIS monitoring data obtained showed a sufficient level of anesthesia depth during surgery in both groups; however, post-anesthesia depression persisted longer in patients in sevoflurane group. Mathematical models for predicting Clavien-Dindo IIIb-V complications and severe postoperative pain syndrome are characterized by high sensitivity and specificity. They include simple clinical and laboratory parameters as well as type of anesthesia as predictors. The limitations of predictive models are also discussed in the article.

Mitochondrial transfer in mammals has been proven to occur both under physiological conditions and during pathological conditions. It has been shown that neighboring cells can exchange mitochondria via nanotunnel tubes. However, there is evidence that free mitochondria, as well as whole mitochondria and individual mitochondrial fragments, can be transported between cells within extracellular vesicles (EVs). This review discusses the methodological aspects of isolation and a minimal set of methods for characterizing mitochondria-rich EVs (mitoEVs), as well as methodological approaches for studying the nucleic acid, protein, and lipid composition. It has been shown that mitoEVs, as well as extracellular mitochondria, contain a characteristic set of nucleic acids of mitochondrial origin. First and foremost, the dominant fraction of mitochondrial nucleic acids is mitochondrial DNA (mtDNA), a circular double-stranded molecule approximately 16.6 thousand base pairs in length. The mechanisms involved in EV internalization include clathrin-dependent endocytosis, caveolin-dependent endocytosis, raft-mediated endocytosis, and macropinocytosis. Mitochondrial-enriched autologous and xenogeneic EVs are thought to be internalized by similar mechanisms. The review also presents the main sources (stem cells, platelet concentrate, peripheral blood mononuclear cells) for obtaining mitochondria-rich EVs for therapeutic purposes.

Background: Sarcopenia is a complex, multifactorial condition characterized by progressive loss of muscle mass, strength, and function. Despite growing awareness, the early diagnosis and pathophysiological characterization of this condition remain challenging due to the lack of integrative biomarkers. Objective: This study aimed to conduct a comprehensive multilevel profiling of clinical parameters, immune cell phenotypes, extracellular vesicle (EV) signatures, and biochemical markers to elucidate biological gradients associated with different stages of sarcopenia. Materials and Methods: A prospective cohort study enrolled adults aged 45–85 years classified as control, presarcopenic, or sarcopenic based on European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria. Clinical evaluation included anthropometry, muscle strength, sarcopenia screening (SARC-F) questionnaire/Short Physical Performance Battery (SPPB) questionnaires, and quality-of-life assessment. Flow cytometry was used to characterize blood monocyte/macrophage subsets (cluster of differentiation 14 (CD14), CD68, CD163, CD206). EVs were isolated from plasma and profiled for surface tetraspanins and matrix metalloproteinases (MMP2, MMP9, tissue inhibitor of metalloproteinase-1 (TIMP-1)) using bead-based flow cytometry. Biochemical assays measured metabolic, inflammatory, and extracellular matrix (ECM)-related markers. Data were analyzed via Kruskal–Wallis testing, discriminant analysis, and principal component analysis (PCA). Results: Sarcopenia, a muscle-wasting condition linked to aging, is characterized by chronic inflammation, proteolytic imbalance, and metabolic disturbances. Clinical deterioration is evident through reduced appendicular lean mass (ALM), appendicular skeletal muscle index (ASMI), SPPB scores, and sarcopenia quality of life (SarQoL) domains. Principal component analysis (PCA) identified four functional marker clusters: ECM degradation (MMP-positive EVs), inflammatory and homeostasis-stabilizing macrophages, and metabolic disruption (glucose, asprosin, triglycerides). Discriminant analysis emphasized vesicular and immune markers with significant classification potential, even when univariate differences were non-significant. Metabolic destabilization and inflammatory activation are detectable in presarcopenia stages. Chronic inflammation, characterized by CD14–CD163+206+ cells releasing pro-inflammatory cytokines, accelerates muscle degradation. Proteolytic dysfunction, with an imbalance between proteases and inhibitors, further contributes to muscle loss. Metabolic disorders impair energy production and nutrient utilization, exacerbating muscle wasting. A comprehensive assessment, including anthropometric, functional, physical activity, and QoL measures, is crucial for identifying high-risk individuals and understanding sarcopenia’s mechanisms. Vesicular biomarkers, regulating tissue remodeling and inflammation, provide valuable insights. Standardized assessment methods are essential for enhancing diagnostic accuracy and intervention effectiveness. Future research should focus on developing and refining biomarkers to improve specificity and sensitivity, enabling targeted therapies and better QoL. Conclusions: Integrating clinical, immunological, and biochemical markers with EVs helps stratify sarcopenia effectively. Our data shows that EVs and macrophage profiles reflect systemic changes and metabolic stress. However, age- and gender-related variability in our cohort warrants caution in generalizing the findings. Artificial intelligence (AI) enhances patient clustering by combining these data types, enabling precise, personalized sarcopenia management, predicting disease progression, and identifying high-risk patients. AI also standardizes and optimizes analytical protocols, improving diagnostic and monitoring reliability and reproducibility.

Circulating small extracellular vesicles (sEVs) are emerging as potential biomarkers for glioblastoma progression. This study aimed to compare the levels of matrix metalloproteinases (MMP2 and MMP9), terminal complement complex (C5b-9), and VEGF-A in circulating sEVs in glioblastoma patients (GBMPs) with and without tumor recurrence. Using differential ultracentrifugation, sEVs were isolated from blood samples of GBMPs with no tumor recurrence for over one year (n = 6) and after first relapse (n = 14). The vesicles were characterized and quantified using flow cytometry. In both groups, C5b-9 was predominantly detected on tumor-specific circulating sEVs (glial fibrillary acidic protein (GFAP)-positive sEVs) with high VEGF-A expression, while C5b-9 was significantly less frequent on sEVs with low VEGF-A expression (p < 0.05). GFAP+VEGF+dimMMP2-C5b-9+ vesicles were rarely detected in GBMPs without relapse, suggesting their potential utility as biomarkers for a favorable relapse-free prognosis. In recurrent GBMPs, a positive correlation was observed between GFAP+VEGF+bright MMP2+C5b-9+ sEVs and MGMT gene promoter methylation levels (r = 0.543, p < 0.05). Additionally, a trend toward a negative correlation was found between GFAP+VEGF+bright MMP2+C5b-9- sEVs and mutant p53 expression in primary tumor tissue (r = −0.44, p = 0.114). These findings suggest that sEV profiles may serve as valuable prognostic markers for glioblastoma recurrence and treatment responses.

Background: Over the past five years, the pregnancy rate in assisted reproductive technology (ART) programs in Russia has remained relatively stable. The aim of this study was to assess the distribution of monocyte and macrophage subsets in the blood and follicular fluid of infertile women undergoing assisted reproductive technology. Methods: The study involved 45 women with a mean age of 35 ± 4.66 years. Monocytes and macrophages were identified using flow cytometry. Results: We observed a decrease in the CD68+CD163+CD206+ and the CD68+CD163–CD206+ cells in patients with a body mass index (BMI) >25 by 0.19 times and 6.56 times, respectively, compared to the group with a BMI <25 (p = 0.031). Patients with fair oocyte quality had 3.6 times more oocytes than those with poor quality (p = 0.010). The relative content of CD14+163–206+ monocytes was found to be 24.15 times higher in the follicular fluid of women with poor embryo quality compared to the group with good embryos (p = 0.010). We also noted that the number of oocytes increased in women with male factor infertility (p = 0.020) and those with unspecified infertility when compared to tubal infertility. An increase in the relative content of CD14+163+206+ in the blood was higher in women with other causes of female infertility compared to those with male factor infertility (p = 0.010). The relative content of M2-monocytes (CD14+163+206–) in the blood was 4.38 times higher in women with male factor infertility than in women with unexplained infertility (p = 0.010). Conclusions: A critical component of the inflammatory reaction in patients undergoing in vitro fertilization (IVF) involves more than just the activation of pro-inflammatory cells in response to ovarian stimulation. Our research shows that changes in the distribution of monocytes and macrophages can influence embryo implantation success and pregnancy outcomes in women. These processes are influenced by various infertility-related factors, including those mentioned above. However, these findings are preliminary and require further investigation.

Extracellular vesicles (EVs) are a heterogeneous population of membrane particles less than 1 μm in size, secreted by various cell types. Most EVs circulating in human blood are particles of platelet, leukocyte, erythrocyte and endothelial origin. The composition of circulating adipocyte EVs in various pathological conditions has been virtually unknown. Small EVs from the blood plasma of patients with colorectal cancer (CRC) and colon polyps with obesity or metabolic syndrome were isolated by ultrafiltration with double ultracentrifugation. To study the composition of adipocyte EVs, immunoprecipitation in combination with Western blotting and flow cytometry were used. Vesicle fractions (FABP4- and CD11b-immunoprecipitated EVs, as well as EVs contained in the supernatant after removal of CD11b-positive EVs) contained a complex of adipocyte markers (FABP4, PPAR-γ and perilipin 1). EVs of monocyte-macrophage origin precipitated on CD11b-coated particles in CRC patients without obesity were characterized by combined overexpression of FABP4 and perilipin 1, while such overexpression was not typical for CRC patients with metabolic syndrome or obesity. The fraction of truly adipocyte vesicles (supernatant after removal of CD11b-positive EVs) was characterized by the presence in all patients of a complex of adipocyte markers with predominant expression of FABP4 in both patients with metabolic syndrome/metabolically healthy obesity and patients without metabolic disorders. To correctly characterize circulating EVs of patients without obesity, it is first necessary to remove the fraction of CD11b-positive monocyte-macrophage EVs from EV preparations by immunoprecipitation or similar methods, and in the supernatant after removal/sorption of precipitated EVs, the composition of adipocyte vesicles can be studied using a set of markers (FABP4, PPAR-γ, perilipin 1, etc.). Moreover, in patients with metabolic disorders, taking into account the insignificant expression of FABP4 in CD11b-immunoprecipitated EVs, preliminary depletion of vesicle preparations is apparently not so necessary.