Šauklytė, Laura

Introduction: Over recent decades, the study of the bacterial microbiome has gained increasing attention due to its vital role in human health. The development of the gut microbiome is especially critical during infancy, as it supports nutrient absorption, metabolic regulation, and immune system maturation. Several perinatal factors, including delivery mode, gestational age, and health status, have been shown to influence micro -biome establishment. Preterm and low-birth-weight infants, in particular, face heightened vulnerability to disruptions in microbiome development, which may contribute to adverse health outcomes. Aims & Methods: This study aimed to analyze the longitudinal development of the gut microbiome in preterm, low-birth-weight neonates over the first two months of life and to identify microbial patterns and alterations associated with delivery mode, gestational age, and clinical conditions. The study cohort included 115 low-birth-weight preterm infants and 99full-term, normal-weight controls. Stool samples from preterm infants were collected at multiple time points between day 1 and day 61 of life and grouped into six age categories for analysis. In total, 819 stool samples were examined. DNA was extracted and amplified targeting the V3–V4 region of the 16S rRNA gene, followed by sequencing on the Illumina MiSeq platform. Microbiome data were analyzed using bioinformatic and statistical tools to assess taxonomic composition, alpha diversity, and beta diversity. Results: Significant differences in microbiome profiles were associated with gestational age, mode of delivery, postnatal age, maternal medication, and the presence of necrotizing enterocolitis (NEC). Bacterial com-munities began to stabilize between days 26 and 35. A total of 56 bacterial genera — including Bifidobacterium, Clostridium, Escherichia-Shigella, Gemella, Klebsiella, Lactobacillus, and Streptococcus — showed a positive correlation with infants’ age in days, while 31 genera — including Bacillus, Cutibacterium, Flavobacterium, Macrococcus, Pseudomonas, and Staphylococcus — were negatively correlated. Eighteen bacterial genera were associated with the mode of delivery at various time points. Genera such as Fusobacterium, Bacteroides, Entero-coccus, Streptococcus, Gemella, and Corynebacterium were more commonly associated with vaginal birth, while Staphylococcus, Rahnella, Yokenella, Millisia, Negativicoccus, Finegoldia, Haemophilus, Acinetobacter, Conservatibacter, Serratia, Stenotrophomonas, and Peptoniphilus were associated with Caesarean section delivery. Moderate differences in early-life microbiome composition were also ob -served between low-birth-weight preterm and full-term infants. Conclusion: Gut microbiome development in preterm, low-birth-weight newborns is strongly influenced by clinical and perinatal factors, particularly during the first month of life. Mode of delivery, gestational maturity, and disease presence such as NEC contribute to microbial variability and delayed community stabilization. These findings highlight the importance of early-life monitoring and tailored interventions to support healthy microbiome development in vulnerable neonates.

Over the past decades, bacterial microbiome studies have become increasingly important. The development of the gut microbiome has been shown to play an essential role in human health, and to be especially decisive in infants [1]. It influences nutrient absorption, metabolism regulation, and immune system development. Various factors have been proposed to modulate the development of the microbiome and therefore shape the growth and health of newborns [2]. Premature babies are often lowweight and even more sensitive to health issues. This study aims to analyse the development of the microbiome in preterm neonates over the first two months of life and look for patterns and alterations associated with several factors, like delivery mode, gestation time and necrotizing enterocolitis (NEC). A total of 78 preterm newborns were included in the study, with stool samples being taken at several timepoints from each baby. In total 515 samples were collected. The timepoints varied between ages of one and 61 days and were grouped in six age groups during the analysis. Genomic DNA was extracted from stool samples, and the bacterial V3–V4 hypervariable region of the 16S rRNA gene was amplified and sequenced on the Illumina MiSeq platform. The data were processed using bioinformatical tools and analysed bioinformatically and statistically to access microbiome composition, abundancies, alpha- and beta-diversities. The analysis revealed significant differences in the bacterial profiles across different timepoints, gestational ages, delivery modes, and in relation to the development of NEC. Alpha diversity indices increased over time; however, fewer or no significant differences were observed between the later timepoints. Consistent patterns emerged from both PCoA and PERMANOVA analyses. Notably, NEC was associated with distinct bacterial. Additionally, the abundance of several bacterial taxa correlated with gestational age. The bacterial profile of premature, low-birth-weight newborns varies according to factors such as age, delivery mode, gestational age, and the presence of disease. Comparing these microbiome dynamics in low-birth-weight infants with those in full-term newborns could provide valuable insights into the development of neonatal diseases such as necrotizing enterocolitis.

Aim: To evaluate the expression changes of miR-146a-5p and miR-31-5p molecules in the blood of patients with inflammatory polyneuropathy. Methods and Subjects: The expression of miR-146a-5p and miR-31-5p molecules was determined in the blood of patients with chronic inflammatory demyelinating polyneuropathy (CIDP, n = 13) and multifocal motor neuropathy (MMN, n = 10) and compared to a control group (n = 40). Blood samples for miRNA expression analysis were collected in specialized “Tempus™ Blood RNA Tubes.” RNA was purified from whole blood using the “mirVana™ miRNA Isolation Kit.” Complementary DNA (cDNA) synthesis was performed using the “TaqMan® Advanced miRNA cDNA Synthesis Kit.” The expression of microRNA molecules was determined by real-time PCR (RT-PCR), and the data were analyzed using the “ThermoFisher Cloud” platform. Statistical analysis was performed using the “IBM SPSS 29.0” software. Results: The ∆CT values of miR-146a-5p and miR-31-5p were compared between the inflammatory polyneuropathy (IPN) and control groups. It was found that the expression of miR-146a-5p significantly differed between the IPN and control groups (p = 0.014). The control group showed higher expression of miR-146a-5p (mean -∆Ct = -9.088) compared to the IPN group (mean -∆Ct = -9.588). Additionally, the ∆CT values of miR-146a-5p and miR-31-5p were compared among the two diseases: CIDP, MMN, and the control group. Analysis of the obtained data confirmed that the ∆CT values of miR-146a-5p significantly differed between the groups (p = 0.047). Conclusion: The expression of miR-146a-5p and miR-31-5p molecules was statistically significantly lower compared to the control group.

Introduction Microscopic colitis (MC) is a chronic inflammatory bowel disease (IBD) characterized by intestinal epithelial barrier disruption due to an excessive immune response to environmental antigens. The dynamics of inflammation in colonic epithelial organoid models remain largely unexplored, particularly the timing of cytokine-induced responses and their resolution [1]. Aim To investigate the dynamics of the inflammatory response in colonic epithelial organoids. Methods Colonic epithelial organoids were derived from control individual biopsies and stimulated with TNF-α and IFN-γ at a single time point. Samples were collected at 2, 4, 8, 12, 24, 36, and 48 hours post-treatment to assess temporal molecular changes. Expression of TNF-α, CXCL9, TJP1, and OCLN was analyzed using qRT-PCR. Results The analysis of pro-inflammatory gene expression (TNF-α and CXCL9) indicates that the inflammatory response in colonic organoids remains elevated and stable for at least 12 hours post-cytokine stimulation. Both genes are significantly upregulated at 2h (TNF-α: FC = 23.1, p = 1.5 × 10⁻³; CXCL9: FC = 4991.2, p = 5.5 × 10⁻⁴), peaking at 4h–8h (TNF-α: FC = 30.5, p = 3.1 × 10⁻⁵; CXCL9: FC = 31288.6, p = 8.3 × 10⁻⁷), and remaining high at 12h (TNF-α: FC = 21.6, p = 5.3 × 10⁻⁴; CXCL9: FC = 21567.4, p = 2.7 × 10⁻⁵). By 24h, inflammation starts to subside (TNF-α: FC = 10.5, p = 7.0 × 10⁻⁵; CXCL9: FC = 14499.0, p = 5.8 × 10⁻⁴), though a sustained response is observed. At 48h, inflammatory marker expression returns to baseline (TNF-α: FC = 9.2, p = 1.4 × 10⁻²; CXCL9: FC = 3111.2, p = 5.8 × 10⁻⁴), similar to 2h levels. Concurrently, the downregulation of OCLN after 4h (FC = 0.8, p = 3.1 x 10-2), 12h (FC = 0.7, p = 2.0 x 10-2) and 48h (FC = 0.7, p = 4.8 x 10-3) of stimulation with inflammatory cytokines had tendency reflect epithelial barrier disruption. Conclusions This study demonstrates that the inflammatory response in colonic epithelial organoids remains elevated and stable for at least 12 hours following cytokine stimulation, with TNF-α and CXCL9 peaking at 4h–8h and gradually declining by 24h–48h. The observed downregulation of OCLN at multiple time points suggests epithelial barrier disruption as a consequence of prolonged inflammation.

Polyneuropathy (PN) is a common nerve disorder that affects the peripheral nerves. PN are characterized by symmetrical and diffuse damage to the peripheral nervous system, potentially affecting motor, sensory, or autonomic nerve fibers. The disease may manifest with muscle weakness, atrophy, paresthesia, pain, decreased and autonomic symptoms. MiRNAs are small, non-coding RNA molecules, about 20-24 nucleotides long, that play a crucial role in the regulation of gene expression. MiR-146a and miR-31 are linked to immune inflammatory diseases and it plays an important role in controlling T and B lymphocytes and dendritic cells. These miRNAs may affect inflammatory mediators that promote or inhibit the immune response. The aim of this study was to perform a heatmap analysis to compare the expression of miR-31-5p and miR-146a-5p between patients with Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) and Multifocal Motor Neuropathy (MMN) and controls. RNA was isolated from blood using mirVana™ miRNA Isolation Kit (ThermoFisher (TF), USA). The cDNR synthesis was performed using the TaqMan® Advanced miRNA cDNA Synthesis Kit (TF, USA). MiRNAs expression was detected by using qRT-PCR method. Results were analyzed using the heat-map method. The significance of the results was assessed using the SPSS Statistics 29.0.2.0. A total of 23 patients with CIDP/MMN and 56 controls were analyzed for miRNA expression in blood. The intensity and gradient of the colors in the heat map indicated the miRNA expression levels and revealed potential differences between CIDP/MMN patients and controls. Heatmap analysis can provide an overview of the miRNA expression profile between the CIDP and MMN subjects and the control group and help identify potential miRNA diagnostic markers.

Background: Multiple sclerosis (MS) is a chronic autoimmune inflammatory disease that affects the central nervous system, primarily characterized by demyelination, which disrupts neuronal function. Remyelination, the process of forming a new myelin sheath around axons, is crucial for MS patients as it helps restore neurological function. MicroRNA (miRNA) molecules, known for their role in regulating gene expression, are believed to play an important role in remyelination. The small, non-coding miR-219 and miR-338 are known to promote oligodendrocyte differentiation by inhibiting negative regulators. These miRNAs have also been shown to work in concert during myelination and myelin sheath repair. The aim of this study was to perform a heat-map analysis to compare the expression of miR-219a-5p and miR-338-5p between MS patients and controls. Methods: Blood samples were collected into special Tempus blood tubes. RNA was isolated from blood using mirVana™ miRNA Isolation Kit (ThermoFisher Scientific (TFS), USA) and the cDNR synthesis was performed using the TaqMan® Advanced miRNA cDNA Synthesis Kit (TFS, USA). MiRNA expression was detected by using qRT-PCR method and the results were analyzed with ThermoFisher Cloud platform. Data visualization was performed using heat-map method. The significance of the results was assessed using SPSS Statistics 29.0.2.0. Results: In this study, miRNA expression in blood samples was analyzed for 20 MS patients and 43 controls. The heat-map analysis revealed that miR-338-5p expression was lower in the patient group. Conclusion: Heat-map analysis offers a comprehensive view of the miRNA expression profiles in MS patients compared to the control group, facilitating the identification of miRNAs as potential diagnostic markers.

Demielinizuojančios ligos – tai grupė patologijų, kurioms būdingas mielino dangalo ir nervinių ląstelių pažeidimas. Mielino dangalas pagerina nervų laidumą ir išsaugo energiją reikalingą veikimo potencialui plisti [1]. Šiai ligų kategorijai yra priskiriama išsėtinė sklerozė ir ūminė uždegiminė demielinizuojanti polineuropatija dar vadinama Guillain – Barre sindromu (GBS) [2, 3]. Pastaraisiais metais mokslininkai skiria daug pastangų ieškant biožymenų, kurie padėtų tiksliau diagnozuoti ligas bei stebėti jų eigą. Remiantis ankstesnių publikacijų autorių rekomendacijomis ištirti didesnį tiriamųjų skaičių dėl duomenų atsikartojamumo, pasirinkome dvi miRNR (miR-146a ir miR-219a), kurios turėjo reikšmingų sąsajų su tirtomis patologijomis. MiRNR yra trumpos, nekoduojančios, vienos grandinės molekulės, daugiausia susijusios su genų raiškos reguliavimu per transkripcijos ir transliacijos slopinimą [4]. MiRNR-146a taikyta ieškant sąsajų su Guillain-Barré sindromu. GBS yra retas autoimuninis sutrikimas [2] potencialiai pavojinga gyvybei periferinės nervų sistemos liga, sukelianti greitai progresuojantį raumenų silpnumą, sausgyslių refleksų praradimą ir kartais kvėpavimo nepakankamumą bei autonominę disfunkciją [5]. Pastebėta, kad dažnai GBS atsiranda praėjus kelioms dienoms ar savaitėms po to, kai pacientui pasireiškia kvėpavimo takų ar virškinimo trakto mikrobinės infekcijos simptomai [2]. Nors patogenezė nėra visiškai aiški, imuninio uždegiminio atsako dalyvavimas yra patvirtintas. Kadangi miRNR-146a reguliuoja uždegimą ir imuninį atsaką bei tarnauja kaip įvairių ligų biožymuo, manoma, kad miR-146a ekspresija gali pakisti GBS pacientams lyginant su sveikais žmonėmis [6]. Naujausi tyrimai atskleidė, kad miR-219a dalyvauja išsėtinės sklerozės patogenezėje [7]. IS yra lėtinė autoimuninė liga, kuriai būdinga uždegiminė demielinizacija ir neurodegeneracija centrinėje nervų sistemoje [3], fiziologinėmis sąlygomis po demielinizacijos įvyksta remielinizacija, dėl kurios demielinizuotą sritį reikia atkurti oligodendrocitų pirmtakų ląstelėmis. Nors IS pažeidimuose yra daug oligodendrocitų pirmtakų ląstelėmių, remielinizacija nepavyksta, galbūt dėl to, kad jos nesugeba diferencijuotis į subrendusias mieliną formuojančias ląsteles. Sumažėjęs miR-219a reguliavimas sergant IS gali prisidėti prie oligodendrocitų pirmtakų ląstelių diferenciacijos sutrikimo, taip trukdydamos remielinizaciją sergant IS [7]. [...].