MicroRNAs in Colon Tissue of Pediatric Ulcerative Pancolitis Patients Allow Detection and Prognostic Stratification

Revitalizing gut barrier integrity: role of miR-192-5p in enhancing autophagy via Rictor in enteritis

Intestinal inflammation and compromised barrier function are critical factors in the pathogenesis of gastrointestinal disorders. This study aimed to investigate the role of miR-192-5p in modulating intestinal epithelial barrier (IEB) integrity and its association with autophagy. A DSS-induced colitis model was used to assess the effects of miR-192-5p on intestinal inflammation. In vitro experiments involved cell culture and transient transfection techniques. Various assays, including dual-luciferase reporter gene assays, quantitative real-time PCR, Western blotting, and measurements of transepithelial electrical resistance, were performed to evaluate changes in miR-192-5p expression, Rictor levels, and autophagy flux. Immunofluorescence staining, H&E staining, TEER measurements, and FITC-dextran analysis were also used. Our findings revealed a reduced expression of miR-192-5p in inflamed intestinal tissues, correlating with impaired IEB function. Overexpression of miR-192-5p alleviated TNF-induced IEB dysfunction by targeting Rictor, resulting in enhanced autophagy flux in enterocytes (ECs). Moreover, the therapeutic potential of miR-192-5p was substantiated in colitis mice, wherein increased miR-192-5p expression ameliorated intestinal inflammatory injury by enhancing autophagy flux in ECs through the modulation of Rictor. Our study highlights the therapeutic potential of miR-192-5p in enteritis by demonstrating its role in regulating autophagy and preserving IEB function. Targeting the miR-192-5p/Rictor axis is a promising approach for mitigating gut inflammatory injury and improving barrier integrity in patients with enteritis.NEW & NOTEWORTHY We uncover the pivotal role of miR-192-5p in fortifying intestinal barriers amidst inflammation. Reduced miR-192-5p levels correlated with compromised gut integrity during inflammation. Notably, boosting miR-192-5p reversed gut damage by enhancing autophagy via suppressing Rictor, offering a potential therapeutic strategy for fortifying the intestinal barrier and alleviating inflammation in patients with enteritis.

MiRNA-192-5p-targeted activated leukocyte cell adhesion molecule improved inflammatory injury of neonatal necrotizing enterocolitis

BACKGROUND

Neonatal necrotizing enterocolitis (NEC) is a common gastrointestinal emergency in neonates. MiRNA-192-5p was found associated with ulcerative colitis (UC) progression, also with aberrant expression in intestinal cancer tissue. However, the effects of miRNA-192-5p on NEC have not been reported.

METHODS

Based on the bioinformatics analysis of the GEO dataset, miR-192-5p was identified as the differentially expressed miRNA in NEC, and activated leukocyte cell adhesion molecule (ALCAM) was predicted as its target. After that, in vitro, rat intestinal epithelial cell-6 (IEC-6) were stimulated with LPS to construct a cell model of NEC. IEC-6 cells were transfected with miRNA-192-5p mimics, miRNA-192-5p inhibitors, or miRNA-192-5p inhibitors + sh-ALCAM, and relevant negative control. In vivo, SD rats were treated with artificial feeding, hypoxic reoxygenation, cold stimulation, and LPS gavage to induce NEC, followed by injection of agomiR-NC or agomiRNA-192-5p. Then effects of miRNA-192-5p on NEC model IEC-6 cell viability, apoptosis, ALCAM expression, Interleukin (IL)-1β and IL-6 levels, intestinal injury, intestinal permeability were detected.

RESULTS

MiRNA-192-5p expression was downregulated in NEC IEC-6 cells, whose overexpression increased IEC-6 cell viability. MiRNA-192-5p inhibitors increased IL-1β, IL-6 levels and promoted IEC-6 cell apoptosis. MiRNA-192-5p targeting of ALCAM decreased ALCAM expression, IL-1β, and IL-6 levels. AgomiRNA-192-5p decreased ALCAM, IL-1β, and IL-6 levels in intestinal tissue and pathological damage and increased miRNA-192-5p levels.

CONCLUSION

MiR-192-5p protects against intestinal injury by inhibiting ALCAM-mediated inflammation and intestinal epithelial cells, which would provide a new idea for NEC treatment.

Let7i A key player and a promising biomarker in diseases

MicroRNAs (miRNAs) are endogenous non-coding single-stranded small RNAs that regulate gene expression by recognizing homologous sequences and interfering with transcriptional, translational or epigenetic processes. MiRNAs are involved in a variety of disease processes, and regulate the physiological and pathological status of diseases by modulating target cell activity, migration, invasion, apoptosis, autophagy and other processes. Among them, let-7i is highly expressed in various systems, which participates in the process of tumors, cardiovascular and cerebrovascular diseases, fibrotic diseases, inflammatory diseases, neurodegenerative diseases and other diseases, and plays a positive or negative regulatory role in these diseases through different signal pathways and key molecules. Moreover, it can be used as an early diagnosis and prognostic marker for a variety of diseases and become a potential therapeutic target. As a biomarker, let-7i is frequently tested in combination with other miRNAs to diagnose multiple diseases and evaluate the clinical treatment or prognosis.

miR-146a-5p regulates autophagy and NLRP3 inflammasome activation in epithelial barrier damage in the in vitro cell model of ulcerative colitis through the RNF8/Notch1/mTORC1 pathway

Ulcerative colitis (UC) is a chronic inflammatory disease affecting the colon that can be influenced by microRNAs (miRNAs). This study aims to investigate the impact of miR-146a-5p on lipopolysaccharide (LPS)-induced Caco-2/HT-29 cell autophagy and NLRP3 inflammasome activation and the underlying mechanism, with the aim of identifying potential therapeutic targets. We used LPS to establish Caco-2/HT-29 cell models and measured cell viability by CCK-8. The levels of miR-146a-5p, RNF8, markers of NLRP3 inflammasome activation and autophagy, proteins involved in the Notch1/mTORC1 pathway, and inflammatory factors were assessed by RT-qPCR, Western blot, and ELISA. Intestinal epithelial barrier function was evaluated by measuring transepithelial electrical resistance. Autophagic flux was measured using tandem fluorescent-labeled LC3. miR-146a-5p was highly-expressed in LPS-induced Caco-2/HT-29 cells, and autophagy flux was blocked at the autolysosomal stage after LPS induction. Inhibition of miR-146a-5p suppressed NLRP3 inflammasome activation, reduced intestinal epithelial barrier damage, and facilitated autophagy inhibition in LPS-induced Caco-2/HT-29 cells. The autophagy inhibitor NH4Cl partially nullified the inhibitory effects of miR-146a-5p inhibition on NLRP3 inflammation activation. miR-146a-5p targeted RNF8, and silencing RNF8 partly abrogated the action of miR-146a-5p inhibition on promoting autophagy and inhibiting NLRP3 inflammasome activation. miR-146a-5p inhibition suppressed the Notch1/mTORC1 pathway activation by upregulating RNF8. Inhibition of the Notch1/mTORC1 pathway partially nullified the function of silencing RNF8 on inhibiting autophagy and bolstering NLRP3 inflammasome activation. In conclusion, miR-146a-5p inhibition may be a potential therapeutic approach for UC, as it facilitates autophagy of LPS-stimulated Caco-2/HT-29 cells, inhibits NLRP3 inflammasome activation, and reduces intestinal epithelial barrier damage by upregulating RNF8 and suppressing the Notch1/mTORC1 pathway.

Identification of Differentially Expressed Genes and miRNAs for Ulcerative Colitis Using Bioinformatics Analysis

Introduction: Ulcerative colitis (UC) is a chronic inflammatory disease of the intestine whose cause and underlying mechanisms are not fully understood. The aim of this study was to use bioinformatics analysis to identify differentially expressed genes (DEGs) with diagnostic and therapeutic potential in UC.

Materials and methods: Three UC datasets (GSE179285, GSE75214, GSE48958) were downloaded from the Gene Expression Omnibus (GEO) database. DEGs between normal and UC tissues were identified using the GEO2R online tool. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the DEGs were performed using Metascape. Protein-protein interaction network (PPI) analysis and visualization using STRING and Cytoscape. Finally, the miRNA gene regulatory network was constructed by Cytoscape to predict potential microRNAs (miRNAs) associated with DEGs.

Results: A total of 446 DEGs were identified, consisting of 309 upregulated genes and 137 downregulated genes. The enriched functions and pathways of the DEGs include extracellular matrix, regulation of cell adhesion, inflammatory response, response to cytokine, monocarboxylic acid metabolic process, response to toxic substance. The analysis of KEGG pathway indicates that the DEGs were significantly enriched in Complement and coagulation cascades, Amoebiasis, TNF signaling pathway, bile secretion, and Mineral absorption. Combining the results of the PPI network and CytoHubba, 9 hub genes including CXCL8, ICAM1, CXCR4, CD44, IL1B, MMP9, SPP1, TIMP1, and HIF1A were selected. Based on the DEG-miRNAs network construction, 7 miRNAs including miR-335-5p, mir-204-5p, miR-93-5p, miR106a-5p, miR-21-5p, miR-146a-5p, and miR-155-5p were identified as potential critical miRNAs.

Conclusion: In summary, we identified DEGs that may be involved in the progression or occurrence of UC. A total of 446 DEGs,9 hub genes and 7 miRNAs were identified, which may be considered as biomarkers of UC. Further studies, however, are needed to elucidate the biological functions of these genes in UC.

Long non-coding RNA SNHG5 regulates ulcerative colitis via microRNA-375 / Janus kinase-2 axis

Ulcerative colitis (UC) is an intestinal inflammatory disorder. Long non-coding RNAs (lncRNAs) are collectively involved in UC. This study is designed to explore the roles of lncRNA (small nucleolar RNA host gene 5) SNHG5 in UC. Gene or microRNA (miRNA) expression was detected using RT-qPCR and western blot, respectively. Cellular functions were analyzed by cell counting kit 8 (CCK8), 5-ethynyl-2'-deoxyuridine (EdU) assay, flow cytometry, and the terminal deoxyribonucleotidyl transferase (TDT)-mediated dUTP-digoxigenin nick end labeling (TUNEL) assays. Lactate dehydrogenase (LDH) content was determined by a cell cytotoxicity assay. The interactions between miR-375 and SNHG5 or Janus kinase-2 (JAK2) were verified by a luciferase reporter assay. SNHG5 was up-regulated in intestinal mucosa tissues of UC patients as well as tumor necrosis factor alpha-treated (TNF-α-treated) young adult mouse colon (YAMC) cells. Down-regulated SNHG5 promoted cell proliferation and inhibited apoptosis of YAMC cells. miR-375 was verified to be a target of SNHG5 and was suppressed by TNF-α treatment in YAMC cells. Over-expression of miR-375 restored YAMC cellular functions. Additionally, miR-375 targeted JAK2, which was up-regulated by TNF-α treated YAMC cells. Up-regulation of JAK2 induced the dysfunction of YAMC cells. Knockdown of SNHG5 promoted the proliferation and suppressed the apoptosis of YAMC cells via regulating miR-375/JAK2 axis. Therefore, knockdown of SNHG5 may be a promising therapy for UC.

miRNA-Based Potential Biomarkers and New Molecular Insights in Ulcerative Colitis

Ulcerative colitis (UC) is a chronic non-specific inflammatory bowel disease, which usually manifests as abdominal pain, diarrhea and hematochezia. The disease often recurs and is difficult to cure. At present, the pathogenesis is not clear, but it is believed that the disease is caused by a complex interaction among immunity, heredity, environment and intestinal microflora disorders. MicroRNA (miRNA) is endogenous single-stranded non-coding RNA of 17–25 nucleotides (nts). They target the 3'Untranslated Region of a target gene and inhibit or degrade the target gene according to the extent of complementary bases. As important gene expression regulators, miRNAs are involved in regulating the expression of most human genes, and play an important role in the pathogenesis of many autoimmune diseases including UC. Studies in recent years have illustrated that abnormal expression of miRNA occurs very early in disease pathogenesis. Moreover, this abnormal expression is highly related to disease activity of UC and colitis-associated cancer, and involves virtually all key UC-related mechanisms, such as immunity and intestinal microbiota dysregulation. Recently, it was discovered that miRNA is highly stable outside the cell in the form of microvesicles, exosomes or apoptotic vesicles, which raises the possibility that miRNA may serve as a novel diagnostic marker for UC. In this review, we summarize the biosynthetic pathway and the function of miRNA, and summarize the usefulness of miRNA for diagnosis, monitoring and prognosis of UC. Then, we described four types of miRNAs involved in regulating the mechanisms of UC occurrence and development: 1) miRNAs are involved in regulating immune cells; 2) affect the intestinal epithelial cells barrier; 3) regulate the homeostasis between gut microbiota and the host; and 4) participate in the formation of tumor in UC. Altogether, we aim to emphasize the close relationship between miRNA and UC as well as to propose that the field has value for developing potential biomarkers as well as therapeutic targets for UC.

lncRNA PVT1 in the Pathogenesis and Clinical Management of Renal Cell Carcinoma

LncRNA PVT1 (plasmacytoma variant translocation 1) has become a staple of the lncRNA profile in patients with renal cell carcinoma (RCC). Common dysregulation in renal tumors outlines the essential role of PVT1 in the development of RCC. There is already a plethora of publications trying to uncover the cellular mechanisms of PVT1-mediated regulation and its potential exploitation in management of RCC. In this review, we summarize the literature focused on PVT1 in RCC and aim to synthesize the current knowledge on its role in the cells of the kidney. Further, we provide an overview of the lncRNA profiling studies that have identified a more or less significant association of PVT1 with the clinical behavior of RCC. Based on our search, we analyzed the 17 scientific papers discussed in this review that provide robust support for the indispensable role of PVT1 in RCC development and future personalized therapy.