Skiecevičienė, Jurgita

Hipofizės adenomos (HA) yra viena dažniausių pirminių smegenų navikų formų, kurioms būdingas heterogeniškas biologinis elgesys – nuo kliniškai indolentinių iki invazyvių ir linkusių kartotis navikų. Nepaisant pažangos diagnostikoje ir gydyme, išlieka poreikis identifikuoti patikimus molekulinius prognozinius žymenis, leidžiančius tiksliau prognozuoti ligos eigą ir individualizuoti pacientų priežiūrą. Šio darbo tikslas – įvertinti telomerų biologijos, JAK–STAT bei somatostatino signalinių kelių genetinių variantų, jų koduojamų baltymų ir santykinio leukocitų telomerų ilgio sąsajas su hipofizės adenomos pasireiškimu bei naviko biologiniu elgesiu (aktyvumu, invazyvumu, atkryčiu ir dydžiu). Tyrime kompleksiškai analizuoti telomerų homeostazėje dalyvaujantys genai (TERT, TERC, TEP1, TERF1, TERF2, TNKS2, CTC1, ZNF676), imuninės signalizacijos komponentai (STAT4) bei somatostatino receptorių sistema (SSTR2, SSTR5, AIP). Taip pat vertintas santykinis leukocitų telomerų ilgis ir Ki-67 proliferacijos indeksas. Nustatyta, kad TERC rs35073794 genetinis variantas yra reikšmingai susijęs su hipofizės adenomos pasireiškimu ir jos dydžiu. HA pacientų grupėje nustatytas didesnis santykinis leukocitų telomerų ilgis, o atskiri telomerų reguliacijoje dalyvaujančių genų variantai (pvz., TERF1, TNKS2, CTC1) siejasi su santykiniu leukocitų telomerų ilgiu bei ligos pasireiškimo galimybe. Imuninės signalizacijos analizė parodė, kad STAT4 genetiniai variantai ir padidėjusi šio baltymo koncentracija yra susiję su didesne HA pasireiškimo galimybe. Ki-67 proliferacijos indeksas daugumai tiriamųjų buvo mažas, o statistiškai reikšmingų sąsajų su naviko biologinėmis savybėmis ar tirtais genetiniais variantais nenustatyta. Atliktas tyrimas yra pirmasis Lietuvoje, kuriame kompleksiškai įvertintos telomerų biologijos, imuninės signalizacijos ir somatostatino receptorių sistemos genetinės bei molekulinės sąsajos su hipofizės adenoma. Gauti rezultatai papildo esamas žinias apie HA patogenezę ir sudaro prielaidas tolesniems tyrimams, orientuotiems į prognozinių žymenų paiešką bei individualizuotos pacientų priežiūros tobulinimą.

Background/Objectives: This study explores the roles of kynurenine and 5-hydroxytryptophan (5-HTP) in modulating gut microbiota and their potential implications for exudative age-related macular degeneration (AMD). By examining the interplay between these metabolites and the microbiome, we aim to uncover novel pathways that may influence the pathogenesis of AMD. Understanding these associations could lead to innovative therapeutic approaches for managing this leading cause of vision loss in the elderly. To investigate the roles of kynurenine and 5-HTP, alongside the composition of the nasopharyngeal microbiota, in patients with exudative AMD. Methods: Blood metabolite profiling was performed using LC–MS–based metabolomics. Metabolites were extracted with cold methanol/water containing internal standards, filtered through a 10 kDa cutoff filter, separated on a ZIC-HILIC HPLC column, and detected using an Orbitrap mass spectrometer. Metabolites were identified using MZmine 2 software. Results: Patients with exudative AMD exhibited a profound systemic shift in tryptophan metabolism, characterized by significantly lower plasma levels of 5-HTP and higher levels of kynurenine compared to control subjects (p < 0.001 for both). Logistic regression analysis confirmed that both metabolites were independent predictors of AMD status; higher kynurenine levels were associated with increased disease probability, while higher 5-HTP levels demonstrated a protective effect. The kynurenine/5-HTP ratio emerged as a robust biomarker, achieving an area under the curve (AUC) of 0.85 with an optimal threshold of 3.43 (74.1% sensitivity, 84.4% specificity). When integrated with age and gender, the diagnostic performance of the model reached an excellent AUC of 0.92. After adjusting for demographic factors, the kynurenine/5-HTP ratio remained a potent independent risk factor, with each unit increase associated with a 6.30-fold increase in the odds of exudative AMD. Conclusions: Exudative AMD is characterized by a shift in tryptophan metabolism toward the kynurenine pathway, with decreased 5-HTP, increased kynurenine, and an elevated kynurenine/5-HTP ratio. This ratio showed a strong independent association with AMD and excellent diagnostic performance, highlighting its potential as a biomarker and its role in disease pathogenesis.

The human gut microbiome comprises bacteria, viruses, and fungi, yet the fungal component (mycobiome) remains poorly characterized. Here, we investigated gut fungal composition and fungal–bacterial interactions in healthy monozygotic and dizygotic twins. Fungal communities showed substantially higher inter-individual variability than bacterial communities. Zygosity, age, and shared environment had no major influence on fungal abundance, similarity, or dominant genera. Candida was the most abundant genus (mean 5.2% in 161 individuals), followed by Geotrichum (3.7% in 132), whereas Saccharomyces was detected less frequently (0.8% in 92). Most bacterial genera were negatively correlated with Candida and Geotrichum, with stronger negative associations observed at higher bacterial abundances (up to rho = −0.6 for Alistipes). Network analysis revealed complex negative correlations among Bacteroides, Prevotella, and Candida. Overall, our findings reveal a highly variable gut mycobiome independent of host zygosity, pointing to a competitive bacterial-fungal interplay as a key regulator of fungal homeostasis in humans.

Introduction Inflamatory bowel disease (IBD) is a chronic inflammatory autoimmune disease affecting the lower gastrointestinal tract, pathologically defined by epithelial barrier disruption, dysregulated immune responses, and characteristics of an autoinflammatory syndrome. Caffeine is a widely consumed methylxanthine found in drinks and some medications. However, its effects and those of its metabolites on intestinal inflammation and epithelial barrier function are not fully understood. Recent advances in the treatment of IBD have led to a paradigm shift in the goals of treatment from symptom-free daily life to mucosal healing. Aim This study examined the impact of caffeine and its main metabolites – paraxanthine, theobromine, and theophylline – on inflammatory signaling and epithelial integrity in gut epithelial models, with relevance to gastrointestinal health and Inflammatory Bowel Disease. Methods Initial evaluation of the caffeine and its main metabolites – theobromine, theophylline, and paraxanthine – was conducted using the Caco-2 intestinal epithelial cell line. This step allowed the identification of the compounds and their concentrations that could have the most significant biological and the least toxic effects on cells. The chosen metabolites were additionally assessed in 3D intestinal epithelial organoids from a patient with ulcerative colitis (n = 1) and a non-IBD donor (n = 1), following a 24-hour induction of inflammation using a combined TNF-α and IFN-γ treatment. To evaluate effects on inflammatory responses and epithelial barrier function, targeted gene expression was analyzed by RT-PCR. In addition, the antioxidant capacity of caffeine metabolites was examined by measuring reactive oxygen species (ROS) using flow cytometry and the DHE assay, while post-inflammatory barrier integrity was assessed using the FITC-dextran permeability assay. Results Although caffeine and paraxanthine altered the expression of certain inflammatory markers, their primary impact was on maintaining epithelial barrier stability. Paraxanthine markedly enhanced the expression of several tight junction components (OCLN, TJP1, CLDN1; p 0.05). Paraxanthine demonstrated a tendency to decrease (17%, p > 0.05) the proportion of organoids permeable to low-molecular-weight dextran, whereas caffeine, the metabolic precursor of this metabolite, increased the permeability of the inflammation-affected barrier by 36% (p < 0.05). Conclusions Caffeine and its primary metabolite, paraxanthine, may support gut epithelial barrier integrity by reestablishing the expression of tight junction–related genes.

Late diagnosis and the lack of effective early detection techniques contribute to the poor prognosis of pancreatic ductal adenocarcinoma (PDAC). To address this challenge, we develop ¹H NMR-based metabolomics-AI platforms employing customized multilayer support vector machine (SVM), AutoGluon, and Tabular Foundation Model (TabPFN) frameworks. These platforms integrate serum metabolomic profiles-including small-molecule metabolites and lipoproteins-with clinical/biochemical parameters (age, CA19-9) and Activin A, derived from 902 participants (424 high-risk controls and 478 PDAC cases). Our TabPFN-based algorithm, PanMETAI, outperform state-of-the-art models. In the Taiwanese training and validation cohort, the model achieved an impressive AUC of 0.99 (95% CI: 0.98-0.99). Its robustness is further confirmed in a Lithuanian external validation cohort (n = 322), which yields an AUC of 0.93 (0.90-0.95). Notably, it identifies key signature patterns that improve early-stage (I/II) PDAC diagnosis and perform well with small sample sizes (n = 50). TabPFN-PanMETAI offers a rapid, accurate, and non-invasive tool for early PDAC detection, with strong potential for clinical application.

Mitochondrial structural and functional changes accompany psoriasis, yet the mitochondrial response to psoriatic inflammation in keratinocytes and fibroblasts remains unexplored. In this study, we investigated the effect of psoriasis-like inflammation (PLI) induced by a cytokine cocktail (interleukin (IL)-17A, IL-22 and tumour necrosis factor (TNF)-α) on mitochondrial network morphology and function in cultured keratinocytes (HaCaT) and fibroblasts (BJ-5ta). In both cell types, PLI triggered the expression of psoriasis-related Elafin and high amounts of cytokines (IL-1, IL-6), interferons (IFN-α, IFN-β, IFN-γ), and chemokines (C-C motif chemokine 5 (CCL5) and IL-8), accompanied by increased mitochondrial membrane potential, reactive oxygen species (ROS) production, respiration suppression, network fragmentation, swelling and cristae disassembly. Stimulated emission depletion (STED) nanoscopy revealed the disappearance of mitochondrial cristae in response to PLI, with the process starting more quickly and being more pronounced in keratinocytes than in fibroblasts. These findings highlight cell-specific mitochondrial responses to psoriatic inflammation, guiding future investigations towards new pharmacological targets for managing psoriasis.

Background: The intestinal microbiota-tryptophan metabolism axis is an important regulator in inflammatory bowel disease (IBD)1 . Gut bacteria convert tryptophan into bioactive metabolites, which act on intestinal cells through the aryl hydrocarbon receptor (AHR)2 . These microbially derived metabolites are known to support mucosal homeostasis2 , yet their direct impact on epithelial barrier responses in Crohn’s disease (CD) compared with non-IBD under inflammatory and non-inflammatory conditions, remains underexplored. Methods: Intestinal epithelial organoids were generated from caecal biopsies of CD patient and non-IBD donor and differentiated for four days. Inflammation was induced with IFN-γ and TNF-α (10ng/mL each, 24h). Tryptophan, tryptamine, nicotinamide, indole-3-acetic acid, and indole-3-propionic acid were applied individually 1h before cytokine exposure and maintained throughout; non-inflamed organoids were exposed for 25h. Working concentration of each metabolite was determined by Caco-2 screening. Total RNA was analyzed by RT-qPCR. Expression of three functional gene groups was evaluated: inflammatory (CXCL9,TNF, IL1B), AHR/xenobiotic metabolism (AHR, UGT1A1, CYP1A1), and barrier-related (TJP1, CLDN1,OCLN, MUC2, LGR5, KI67). Data were processed in RStudio, statistical significance level was set to padj. ≤ 0.05. Results: In non-inflamed CD organoids, tryptophan metabolites induced AHR pathway genes such as CYP1A1 and UGT1A1, showing increases of approximately 5-8 log2 FC, but did not increase barrier-related transcripts. Inflammatory stimulation strongly upregulated CXCL9, IL1B, and TNF, with increases of approximately 5-11 log2 FC, while reducing barrier markers expression by about 1-2 log2 FC. Metabolite co-treatment during inflammation maintained AHR activation and partially restored OCLN expression by about 0.6-0.8 log2 FC. In non-IBD organoids, metabolites upregulated both AHR-related genes such as CYP1A1, with increases of approximately 5-7 log2 FC, and barrier genes including CLDN1, OCLN, MUC2, and LGR5, which rose by about 1-2 log2 FC. Inflammation caused weaker immune activation than in CD and moderately reduced barrier genes, while metabolite treatment partly restored OCLN expression by about 0.5-0.7 log2 FC, with limited effects on other barrier markers. Although trends were consistent, not all log2 FC values were statistically significant. Conclusion: In conclusion, microbially derived tryptophan metabolites activate epithelial AHR signaling in both CD and non-IBD organoids, but barrier regulation differs. Therefore, our results indicate diagnosis-specific epithelial sensitivity to microbial products.

Background: The incidence and prevalence of inflammatory bowel disease (IBD) are rising worldwide. The 2010 European inception cohort study demonstrated a gradient (2:1) between Western and Eastern European countries. At that time, the incidence of IBD in the Kaunas region of Lithuania was 8.5 per 100,000 population (6.1 for UC and 2.4 for CD). Recent data from Central and Eastern Europe remain limited, although clinical practice suggests a possible increase in IBD burden. This study aimed to describe contemporary epidemiological trends of ulcerative colitis (UC) and Crohn’s disease (CD) in Lithuania using national administrative datasets. Methods: A retrospective, population-based study was conducted using anonymized data from the Lithuanian State Data Reuse Platform for 2020–2024. All residents with at least one recorded UC or CD diagnosis were included. Incident cases were identified by the first disease entry following a three-year lookback period. Annual crude incidence and prevalence rates per 100,000 population were calculated. Trends in hospitalizations and pharmacological treatment were analyzed descriptively. Results: In total, 5601 UC and 1500CD cases were identified. The mean annual UC incidence was 20.2 per 100,000 (17.5, 19.9, 22.8, 21.9, and 20.2 for 2020–2024, respectively), and the mean annual prevalence was 131.2 per 100,000. For CD, the mean annual incidence was 6.4 (5.3, 5.9, 7.4, 6.5, 7.0 for 2020–2024, respectively), and the mean annual prevalence was 31.8 per 100,000. The mean age at diagnosis was 42 years (SD 18.6) for UC and 38 years (SD 19.9) for CD. Mean annual hospitalization rates were 10.6% for UC and 17.8% for CD, remaining stable throughout 2020–2024. The use of advanced therapies among UC patients increased from 4% in 2020 to 11% in 2024, and among CD patients from 19% to 26% over the same period. Conclusion: Our data show significantly higher IBD incidence and prevalence rates in Lithuania compared to those reported in 2007–2010. The use of advanced therapies continued to rise, whereas hospitalization rates remained stable.

Background Collagenous colitis (CC) is a form of microscopic colitis (MC) and is characterized by chronic watery diarrhoea and urgency sometimes leading to incontinence resulting in significantly decreased quality of life1. MC is thought to develop due to a pathological immune response to intestinal luminal antigens in genetically predisposed individuals2. Intestinal microbiota is thought to play a key role in the pathogenesis of MC3. However, neither the pathogenesis of MC nor the role of microbiota in its development are fully understood. The aim of our study was to create a mouse model of CC using faecal microbiota transplantation (FMT) in order to gain further insight into the role of gut microbiota in MC pathogenesis.

Methods In the model we used C57BL/6 mice (8 weeks old) across seven treatment groups (n = 10/group). This included 2 control groups (one receiving no FMT and one receiving FMT from healthy controls) and 5 groups receiving FMT prepared from different CC donors. The FMT was performed via enema after broad spectrum antibiotic treatment and bowel cleansing. Afterwards the mice received FMT daily via the oral route. The mice were followed up for 24 weeks. Blood analysis and 16S rRNA sequencing of fecal samples were performed at multiple time points. At the end of the experiment, histological analysis of the animals’ digestive tract was performed.

Results
Significant decreases in alpha diversity (Shannon) and alterations in bacterial composition were observed across all groups after antibiotic treatment. Beta diversity analysis at different timepoints revealed that mouse microbiome composition steadily drifted towards baseline across all groups (figure 1), with donor microbiota accounting for a small fraction (<1-2 %) by week 24 across all FMT groups. Throughout the experiment, microbiota changes exhibited significant heterogeneity within groups, with individual differences, rather than FMT, being the primary factor. Immune cell analysis in the blood showed a dynamic pattern: white blood cell and lymphocyte counts declined initially, peaked at 8 weeks, and stabilized by 24 weeks. Granulocyte levels fluctuated markedly, reaching their highest point at 16 weeks, whereas monocyte counts remain stable throughout. Histological analysis revealed no morphological changes of the mice digestive tract across all groups.

Conclusion FMT from CC donors failed to induce inflammatory changes in mice.

Diet and psychological stress are recognized contributors to inflammatory bowel disease (IBD), yet their interaction-particularly stress-induced eating-remains underexplored. This study examined how perceived stress relates to comfort food consumption (CFC) and patient-reported outcomes among individuals with IBD. A cross-sectional online survey was conducted with 2,254 Italian patients recruited via a national patient organization. Participants completed the Perceived Stress Scale, Salzburg Stress Eating Scale, IBD Symptom Inventory, Bristol Stool Chart, and ad hoc items on CFC. Analyses included partial correlations controlling demographic and clinical covariates, group comparisons by stress level and IBD subtype, and latent class analysis (LCA) to identify psychosocial profiles. Participants reported moderate stress and increased CFC under stress. Those with higher perceived stress described greater symptom burden, softer stool consistency, more frequent CFC, and stronger emotional reliance on these foods. The LCA identified two subgroups-one low-stress/low-symptom and another high-stress/high-symptom/high-comfort-food-highlighting a stress-reactive behavioral phenotype. Stress-eating scores and food preferences did not differ by disease subtype, although patients with Crohn's disease reported higher symptom severity and softer stools. Findings underscore perceived stress as a key psychological correlate of eating behaviors and symptom perception in IBD, supporting the integration of patient-reported experiences into multidisciplinary, engagement-oriented care.