Normal Intestinal Epithelial Cells Research Articles

MIMC-β: microdosimetric assessment method for internal exposure of β-emitters based on mesh-type cell cluster model

The method combining Monte Carlo (MC) simulation and mesh-type cell models provides a way to accurately assess the cellular dose induced byβ-emitters. Although this approach allows for a specific evaluation of various nuclides and cell type combinations, the associated time cost for obtaining results is relatively high. In this work, we propose a Microdosimetric assessment method for Internal exposure ofβ-emitters based on Mesh-type Cell cluster models (abbreviated as MIMC-β). This approach is applied to evaluate the dose in various types of cells (human bronchial epithelial cells, BEAS-2B; normal human liver cells, L-O2; and normal human small intestine epithelial cells, FHs74Int) exposed toβ-emitters. Furthermore, microdosimetric quantity based on the cell cluster model are employed to estimate the relative biological effectiveness (RBE) ofβ-emitters. The results indicate that this method can accurately and rapidly predict cellular doses caused by different types ofβ-emitters, significantly mitigating the efficiency challenges associated with directly employing MC to estimate the overall dose of the mesh-type cell cluster model. In comparison with results obtained from direct simulations of uniform administration ofβ- sources using PHITS for validation, the cellular cluster overallS-values obtained through MIMC-βshow discrepancies mostly below 5%, with the minimum deviation reaching 1.35%. Small sampling sizes within the cell nucleus led to larger average lineal energies. In comparison to C-14, the differences in cellular cluster average lineal energy for Cs-134, Cs-137, and I-131 are negligible, resulting in close numerical estimations of RBE based on lineal energy. The MIMC-βcan be extended to diverse cell types andβ-emitters. Additionally, the RBE assessment based on the cell cluster model offers valuable insights for predicting radiobiological damage resulting from internal exposure byβ-emitters. This method is expected to find applicability in various realistic scenarios, including radiation protection and radioligand therapy.

Oleanolic acid improves 5-fluorouracil-induced intestinal damage and inflammation by alleviating intestinal senescence

5-Fluorouracil (5-FU) is used as a standard first-line drug for colorectal cancer malignancy (CRC), but it brings a series of side effects such as severe diarrhea and intestinal damage. Our previous study found that a large number of senescent cells increased while 5-Fu induced intestinal damage, and anti-senescence drugs can alleviate its side effects of inflammatory damage. Oleanolic acid (OA) is a common pentacyclic triterpenoid mainly derived from food fungi and medicinal plants, and studies have shown that it mainly possesses hepatoprotective, enzyme-lowering, anti-inflammatory, and anti-tumor effects. But its role in senescence is still unclear. In the present study, we demonstrated for the first time that OA ameliorated 5-Fu-induced human umbilical vein endothelial cells (HUVECs) and human normal intestinal epithelial cells (NCM460) in a 5-Fu-induced cellular senescence model by decreasing the activity of SA-β-gal-positive cells, and the expression of senescence-associated proteins (p16), senescence-associated genes (p53 and p21), and senescence-associated secretory phenotypes (SASPs: IL-1β, IL-6, IL-8, IFN-γ and TNF-α). Meanwhile, in this study, in a BALB/c mouse model, we demonstrated that 5-FU induced intestinal inflammatory response and injury, which was also found to be closely related to the increase of senescent cells, and that OA treatment was effective in ameliorating these adverse phenomena. Furthermore, our in vivo and in vitro studies showed that OA could alleviate senescence by inhibiting mTOR. In colon cancer cell models, OA also enhanced the ability of 5-FU to kill HCT116 cells and SW480 cells. Overall, this study demonstrates for the first time the potential role of OA in counteracting the side effects of 5-FU chemotherapy, providing a new option for the treatment of colorectal cancer to progressively achieve the goal of high efficacy and low toxicity of chemotherapy.

Critical Suitability Evaluation of Caco-2 Cells for Gut-on-a-Chip.

Currently, culturing Caco-2 cells in a Gut-on-a-chip (GOC) is well-accepted for developing intestinal disease models and drug screening. However, Caco-2 cells were found to overexpress surface proteins (e.g., P-gp) compared with the normal intestinal epithelial cells in vivo. To critically evaluate the challenge and suitability of Caco-2 cells, a GOC integrated with a carcinoembryonic antigen (CEA) biosensor was developed. This three-electrode system electrochemical sensor detects CEA by antigen-antibody specific binding, and it exhibits high selectivity, excellent stability, and good reproducibility. Under dynamic culturing in the GOC, Caco-2 cells exhibited an intestinal villus-like structure and maintained tissue barrier integrity. Meanwhile, CEA was discovered to be secreted from 0 to 0.22 ng/mL during the 10-day culturing of Caco-2 cells. Especially, CEA secretion increased significantly with the differentiation of Caco-2 cells after 6 days of culturing. The sustained high-level CEA secretion may induce cells to avoid apoptotic stimuli, which faithfully reflects the efficacy of a new drug and the mechanism of intestinal disease. Different kinds of cell types (e.g., intestinal primary cells, stem cell-induced differentiation) in the GOC should be attempted for drug screening in the future.

Selection of trophoblast cell surface antigen 2-targeted aptamer for the development of cytotoxic aptamer-drug conjugate

Trophoblast cell surface antigen 2 expressed in several malignant cancers promotes tumor growth and metastasis via several signal transduction pathways. Trop2 is reputed as a prospective biomarker and therapeutic target. Trophoblast cell surface antigen 2-targeted agents, including antibodies, antibody conjugates and therapeutic combinations, could be utilized to fight cancers. To develop an effective drug targeting strategy, we resorted to a new trophoblast cell surface antigen 2-targeted anticancer treatment through aptamer conjugated with chemotherapeutic drug. This study identified trophoblast cell surface antigen 2-specific ssDNA aptamers using engineered trophoblast cell surface antigen 2 overexpression cells for cell-SELEX. The obtained ssDNA aptamer bound to trophoblast cell surface antigen 2 overexpressed cells with nanomolar affinity and was specific for several tumor cell types which express trophoblast cell surface antigen 2 abundantly. Significant cytotoxicity against HT29 cell by the conjugate of trophoblast cell surface antigen 2 aptamer and Emtansine was observed while resulting negligible therapeutic effect on human normal intestinal epithelial cell line HIEC in vitro, indicating that the conjugate shows potential as a promising therapeutic agent. Furthermore, the isolated aptamer demonstrated the ability for the targeted delivery, resulting excellent therapeutic effectiveness of aptamer-drug conjugate for xenograft tumor model of mice with human colorectal cancer.

Hsa-miR-181a-2-3p inhibits the oncogenicity of colon cancer by directly targeting STING.

Colon cancer is a common malignant tumor of the gastrointestinal system, which is characterized by high morbidity and mortality. The purpose of this study was to analyze the expression and biological role of miR-181a-2-3p in colon cancer and to investigate the molecular mechanism of its regulatory effect on colon cancer through stimulator of interferon genes (STING). Real-time reverse transcription polymerase chain reaction (qRT-PCR) assay was used to detect the expression of miR-181a-2-3p in colon cancer cell lines and normal intestinal epithelial cells. After overexpression of miR-181a-2-3p in colon cancer cell lines SW480 and HT29, cells were examined by CCK8, Transwell, and flow cytometry assays for alterations in proliferation, migration, apoptosis, and cell cycle. Target genes of miR-181a-2-3p were predicted by bioinformatics and validated by dual luciferase assays. Rescue experiments were performed to explore the role of STING in the effect of miR-181a-2-3p. The effect of miR-181a-2-3p on colon cancer proliferation in vivo was validated by nude mouse tumorigenicity assay. miR-181a-2-3p was lowly expressed in both colon cancer tissues and cell lines. Overexpression of miR-181a-2-3p led to reduced proliferation and migration, increased apoptosis, and altered cell cycle in colon cancer cell lines SW480 and HT29. STING was a target gene of miR-181a-2-3p. Increased STING expression partially counteracted the effect of overexpression of miR-181a-2-3p on colon cancer cell lines. miR-181a-2-3p also suppressed colon cancer proliferation in vivo. miR-181a-2-3p inhibits the proliferation and oncogenicity of colon cancer, and its molecular mechanism could be inhibited by STING.

Synthesis and Biological Activity of 2-Chloro-8-methoxy-5-methyl-5H-indolo [2,3-b] Quinoline for the Treatment of Colorectal Cancer by Modulating PI3K/AKT/mTOR Pathways.

Developing novel drugs from natural products has proven to be a very effective strategy. Neocryptolepine was isolated from Cryptolepis sanguinolenta, a traditional endemic African herb, which exerts a wide range of biological activities such as antimalaria, antibacterial, and antitumor. 2-Chloro-8-methoxy-5-methyl-5H-indolo [2,3-b] quinoline (compound 49) was synthesized, and its cytotoxicity was assessed on pancreatic cancer PANC-1 cells, colorectal cancer HCT116 cells, liver cancer SMMC-7721 cells, and gastric cancer AGS cells in vitro. The results of the in vitro assay showed that compound 49 exerted remarkable cytotoxicity on colorectal cancer HCT116 and Caco-2 cells. The cytotoxicity of compound 49 to colorectal cancer HCT116 cells was 17 times higher than that of neocryptolepine and to human normal intestinal epithelial HIEC cells was significantly reduced. Compound 49 exhibited significant cytotoxicity against the colorectal cancer HCT116 and Caco-2 cells, with IC50 of 0.35 and 0.54 μM, respectively. The mechanism of cytotoxicity of compound 49 to colorectal cancer HCT116 and Caco-2 cells was further investigated. The results showed that compound 49 could inhibit colony formation and cell migration. Moreover, compound 49 could arrest the cell cycle at the G2/M phase, promote the production of reactive oxygen species, reduce mitochondrial membrane potential, and induce apoptosis. The results of Western blot indicated that compound 49 showed cytotoxicity on HCT116 and Caco-2 cells by modulating the PI3K/AKT/mTOR signaling pathway. In conclusion, these results suggested that compound 49 may be a potentially promising lead compound for the treatment of colorectal cancer.

Development of a Novel Prognostic Panel for Colorectal Cancer Based on Cancer Functional Status, and Validation of STC2 as a Promising Biomarker.

Improving the clinical outcome of colorectal cancer (CRC) patients remains a major challenge. This study aimed to develop a new predictive classifier for CRC and to examine its relationship with the immune environment and therapeutic response. A comprehensive bioinformatics analysis was applied to develop a risk panel comprised of cancer function status-related genes (CFSRGs). This panel was evaluated for prognostic utility by Area Under the Curve (AUC) and Kaplan-Meier (KM) analyses. Differences between high- and low-risk groups were subsequently investigated using multi-omics data. Immunohistochemistry (IHC), quantitative real-time polymerase chain reaction (qRT-PCR), and cell phenotype assays were also employed to ascertain the clinical value of STC2 expression. Significant differences were observed in the survival rate between high- and low-risk groups defined by our 7-CFSRG panel, both in internal and external CRC patient cohorts. The AUC for prediction of survival at 1-, 3- and 5-years was satisfactory in all cohorts. Detailed analysis revealed that tumor mutation burden, drug sensitivity, and pathological stage were closely associated with the risk score. Elevated expression of STC2 in CRC tissues relative to normal paraneoplastic tissues was associated with less favorable patient outcomes. qRT-PCR experiments confirmed that STC2 expression was significantly upregulated in several CRC cell lines (HCT116, SW480, and LOVO) compared to a normal intestinal epithelial cell line (NCM460). The proliferation, migration, and invasion of CRC cells were all significantly inhibited by knockdown of STC2. Our 7-CFSRG panel is a promising classifier for assessing the prognosis of CRC patients. Moreover, the targeting of STC2 may provide a novel therapeutic approach for improving patient outcomes.

Disturbance of bile acids profile aggravates the diarrhea induced by capecitabine through inhibiting the Wnt/β-catenin pathway

IntroductionDiarrhea is the primary dose-limiting side effect of capecitabine(Cap) hindering its clinical application, but the mechanism is unclear. Clarifying this mechanism may enhance the patient compliance and improve the treatment outcome. ObjectivesTo assess if the endogenous metabolic profile could prodict the diarrhea induced by Cap and explore and validate underlying mechanisms. MethodsUntargeted and targeted bile acids(BAs) metabolomics were performed to analyzed the metabolic profile of baseline samples from colorectal cancer(CRC) patients and the association with the diarrhea induced by Cap was assessed. The toxicity of BAs and Cap and its metabolites alone or their combinations to the human normal intestinal epithelial cell(HIEC) was assessed, and the key genes that mediated the BAs-enhanced toxicity of Cap were discovered by RNA-seq and then validated. A mouse model with high exposure levels of BAs was constructed and then treated with Cap to verify the Cap-induced diarrhea enhanced by BAs. ResultsThe baseline endogenous metabolic profile showed obviously difference between diarrhea and non-diarrhea CRC patients, and the differential metabolites mainly enriched in BAs metabolism; the deoxycholic acid(DCA) and lithocholic acid(LCA) were selected to be the key BAs that enhanced the toxicity of Cap metabolite 5-FU to the HIEC cell; the DCA and LCA could inhibit the Wnt/β-catenin signaling pathway, which then suppressed the P-glycoprotein and increased the exposure level of 5-FU in the HIEC cell. The results of animal experiment verified that the excessive DCA and LCA could aggravate the Cap-induced diarrhea through inhibiting Wnt/β-catenin-P-glycoprotein pathway. ConclusionsThe disordered BAs metabolic profile showed close relationship with diarrhea induced by Cap, and excessive DCA and LCA were proved to be the key BAs, which could aggravate the Cap-induced diarrhea through inhibiting Wnt/β-catenin-P-glycoprotein pathway.

Traditional medicine Xianglian pill suppresses high-fat diet-related colorectal cancer via inactivating TLR4/MyD88 by remodeling gut microbiota composition and bile acid metabolism

Ethnopharmacological relevancePrevious studies have revealed that a high-fat diet (HFD) promotes the progression of colorectal cancer (CRC) in close association with disturbances in the intestinal flora and metabolic disorders. Xianglian pill (XLP) is a well-established traditional prescription with unique advantages in controlling intestinal flora imbalance and inflammation. However, its therapeutic effects on HFD-related CRC remain largely unknown. Aim of the studyThe primary objective of this research was to investigate the anticancer mechanism of XLP in countering HFD-related CRC. Materials and methodsThe protective effect of XLP was evaluated using azoxymethane (AOM) and dextran sulfate sodium (DSS)-induced CRC model of mice exposed to a HFD. The degree of colorectal carcinogenesis, including body weight, colon length, and histopathology, was measured in mice treated with XLP and untreated mice. The effect of XLP on gut microbiota and its metabolites was detected using 16S rDNA and liquid chromatography/mass spectrometry analysis. Furthermore, a “pseudo-sterile” mouse model was constructed using antibiotics (Abx) to verify whether the gut microbiota and metabolites play a role in the pathogenesis of CRC. ResultsXLP inhibited colorectal tumorigenesis in a dose-dependent fashion. Our findings also highlighted that XLP protected the integrity of the intestinal barrier by reducing the expression of pro-inflammatory cytokines, such as IL-6 and TNF-α, as well as the infiltration of pro-inflammatory macrophages. Mechanistically, XLP inhibited the TLR4/MyD88 pathway. Notably, the XLP treatment increased the proportion of probiotics (particularly Akkermansia) and significantly reduced fecal deoxycholic acid (DCA), a microbiota-derived metabolite of bile acids (BA) closely related to Muribaculaceae. Furthermore, after Abx treatment, XLP showed no clear antitumor effects on CRC. Simultaneously, DCA-supplemented feedings promoted colorectal tumorigenesis and provoked obvious colonic inflammation, M1 macrophage infiltration, and colonic injury. In vitro, the results of RAW-264.7 macrophages and normal intestinal epithelial cells treated with DCA corroborated our in vivo findings, demonstrating consistent patterns in inflammatory responses and intestinal barrier protein expression. ConclusionOur findings suggest that XLP inhibits colorectal cancer associated with HFD via inactivating TLR4/MyD88 by remodeling gut microbiota composition and BA metabolism.

PLK1-activating IFI16-STING-TBK1 pathway induces apoptosis of intestinal epithelial cells in patients with intestinal Behçet's syndrome.

Inflammatory signals from immunological cells may cause damage to intestinal epithelial cells (IECs), resulting in intestinal inflammation and tissue impairment. Interferon-γ-inducible protein 16 (IFI16) was reported to be involved in the pathogenesis of Behçet's syndrome (BS). This study aimed to investigate how inflammatory cytokines released by immunological cells and IFI16 participate in the pathogenesis of intestinal BS. RNA sequencing and real-time quantitative PCR (qPCR) showed that the positive regulation of tumor necrosis factor-α (TNF-α) production in peripheral blood mononuclear cells (PBMCs) of intestinal BS patients may be related to the upregulation of polo like kinase 1 (PLK1) in PBMCs (P = 0.012). The plasma TNF-α protein level in intestinal BS was significantly higher than in healthy controls (HCs; P = 0.009). PBMCs of intestinal BS patients and HCs were co-cultured with human normal IECs (NCM460) to explore the interaction between immunological cells and IECs. Using IFI16 knockdown, PBMC-NCM460 co-culture, TNF-α neutralizing monoclonal antibody (mAb), stimulator of interferon genes (STING) agonist 2'3'-cGAMP, and the PLK1 inhibitor SBE 13 HCL, we found that PLK1 promotes the secretion of TNF-α from PBMCs of intestinal BS patients, which causes overexpression of IFI16 and induces apoptosis of IECs via the STING-TBK1 pathway. The expressions of IFI16, TNF-α, cleaved caspase 3, phosphorylated STING (pSTING) and phosphorylated tank binding kinase 1 (pTBK1) in the intestinal ulcer tissue of BS patients were significantly higher than that of HCs (all P < 0.05). PLK1 in PBMCs of intestinal BS patients increased TNF-α secretion, inducing IEC apoptosis via activation of the IFI16-STING-TBK1 pathway. PLK1 and the IFI16-STING-TBK1 pathway may be new therapeutic targets for intestinal BS.

Liensinine sensitizes colorectal cancer cells to oxaliplatin by targeting HIF-1α to inhibit autophagy

BackgroundOxaliplatin is the most common chemotherapeutic agent for patients with colorectal cancer. However, its anti-cancer efficacy is restricted by drug resistance occurring through several mechanisms, including autophagy. Liensinine exerts a considerable anti-tumor effect and can regulate autophagy. Inhibition of autophagy is a strategy to reverse resistance to oxaliplatin. The aim of this study was to check if liensinine can enhance the therapeutic efficacy of oxaliplatin in colorectal cancer and if so, elucidate its mechanism. MethodsTwo colorectal cancer cell lines, HCT116 and LoVo, and one normal intestinal epithelial cell, NCM-460 were used for in vitro experiments. Cell Counting Kit-8 (CCK-8), colony formation, and flow cytometry assays were used to evaluate the cytotoxicity of liensinine and oxaliplatin. Network pharmacology analysis and Human XL Oncology Array were used to screen targets of liensinine. Transfections and autophagy regulators were used to confirm these targets. The relationship between the target and clinical effect of oxaliplatin was analyzed. Patient-derived xenograft (PDX) models were used to validate the effects of liensinine and oxaliplatin. ResultsCCK-8 and colony formation assays both showed that the combination treatment of liensinine and oxaliplatin exerted synergistic effects. Results of the network pharmacology analysis and Human XL Oncology Array suggested that liensinine can inhibit autophagy by targeting HIF-1α/eNOS. HIF-1α was identified as the key factor modulated by liensinine in autophagy and induces resistance to oxaliplatin. HIF-1α levels in tumor cells and prognosis for FOLFOX were negatively correlated in clinical data. The results from three PDX models with different HIF-1α levels showed their association with intrinsic and acquired resistance to oxaliplatin in these models, which could be reversed by liensinine. ConclusionsResearch on the relationship between HIF-1α levels and the clinical effect of oxaliplatin is lacking, and whether liensinine regulates HIF-1α is unknown. Our findings suggest that liensinine overcomes the resistance of colorectal cancer cells to oxaliplatin by suppressing HIF-1α levels to inhibit autophagy. Our findings can contribute to improving prognosis following colorectal cancer therapy.

Explore Key Genes and Mechanisms Involved in Colon Cancer Progression Based on Bioinformatics Analysis.

To explore underlying mechanisms related to the progression of colon cancer and identify hub genes associated with the prognosis of patients with colon cancer. GSE10950 and GSE62932 were downloaded from the Gene Expression Omnibus (GEO) database. GEO2R was utilized to screen out the differentially expressed genes (DEGs). Gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were conducted on DEGs. Moreover, STRING and Cytoscape software were utilized for establishing the network of protein-protein interaction (PPI) and identifying hub genes. Afterward, data from The Cancer Genome Atlas (TCGA) was utilized for identifying prognosis-related hub genes by Kaplan-Meier survival analysis. Colon cancer cell line LOVO and human normal intestinal epithelial cell line NCM-460 were exploited to demonstrate the differential expression of selected hub genes through RT-qPCR and western blot. The LOVO cells were transfected to regulate expressions of prognosis-associated genes, followed by exploring the effects of those genes on prognosis by Cell Counting Kit-8 assay and colony-forming assay for cancer cell proliferation, cell scratch test and transwell migration assay for cancer cell migration and Annexin V-PE/7-AAD double staining as well as flow cytometry for cancer cell apoptosis. In this study, 266 common DEGs were obtained from the intersection of two datasets. The GO analysis suggested the common DEGs mainly participated in the one-carbon metabolic process, cell cycle G2/M phase transition, organelle fission, cell cycle phase transition regulation, and regulation of mitotic cell cycle phase transition. The KEGG analysis demonstrated the common DEGs were related to the p53 signaling pathway, nitrogen metabolism, mineral absorption, and cell cycle. 10 hub genes including CCNB1, KIF4A, TPX2, MT1F, PRC1, PLK4, CALD1, MMP9, CLCA1, and MMP1 were identified and CCNB1, CLCA1, and PLK4 were prognosis-related. Increased expression of CCNB1, CLCA1, and PLK4 restrained proliferation as well as migration of cancer cells and induced apoptosis of cancer cells. CCNB1, KIF4A, TPX2, MT1F, PRC1, PLK4, CALD1, MMP9, CLCA1, and MMP1 were identified as hub genes and CCNB1, CLCA1, and PLK4 could inhibit the progression of colon cancer through inhibiting proliferation as well as migration of the cancer cell and promoting apoptosis of cancer cell.

P054 R. intestinalis improves inflammatory bowel disease by preventing gut uric acid absorption through inhibiting METTL3 mediated m6A modification of SLC2A9

Abstract Background Inflammatory bowel disease (IBD) is a chronic inflammatory disease with persistent, recurrent, unsatisfactory response, and a poor prognosis. The incidence of Chinese IBD has increased rapidly, and Westernized diets such as purine-rich foods play an important role in its rapid growth. The alteration of purine-urate metabolism by microbiota may contribute to the development of IBD. Methods In this study, metagenomic and metabolomic analyses were performed on fecal samples from 30 untreated IBD patients and 30 healthy controls. R. intestinalis was used to observe the effect on serum uric acid levels in mice, respectively. Body weight, colon length, disease activity score, serum uric acid levels, and electron microscopy were all assessed. The RNAseq analysis of intestinal tissue from DSS-induced colitis mice intervened with R. intestinalis and co-cultured with R. intestinalis and the normal intestinal epithelial cell line NCM460, combined with m6A antibody dot blot assay, RM2Target database, and MeRIP sequencing data analysis, provided evidence that SLC2A9 was modified by METTL3, and SRAMP database predicted the potential for SLC2A9 mRNA to be modified by m6A after R. intestinalis intervention. Results Multi-omics analysis revealed that the abundance of R. intestinalis was significantly decreased in untreated IBD patients, and metabolomics revealed a correlation between high uric acid levels and disease severity, while the multi-omics integrated analysis suggested a significant negative correlation between R. intestinalis and uric acid. The research team confirmed that R. intestinalis can lower blood uric acid levels in mice and found that R. intestinalis intervention can alleviate the intestinal mucosal inflammation exacerbated by uric acid treatment in a DSS-induced mouse colitis model. Butyric acid has been reported to regulate m6A, and dot blot assays showed that R. intestinalis can reduce the m6A modification level of intestinal epithelial cells, METTL3, and SLC2A9. RM2Target database identified the protein-RNA interaction of the m6A regulator (WER) for SLC2A9 mRNA, and MeRIP sequencing data further indicated that METTL3 can bind to SLC2A9 mRNA through m6A modification. Meanwhile, based on sequence prediction, the research team identified 13 potential m6A modification sites on SLC2A9 mRNA, of which 4 sites had extremely high credibility . The highest credibility site had a score of 0.694, with a modification site sequence of GGACU located on an adenosine nucleotide. Conclusion R. intestinalis inhibit the METTL3 mediated m6A modification of intestinal epithelial SLC2A9, reducing the expression of SLC2A9, preventing the epithelial absorption of uric acid, and relieving IBD-related colitis

Fatty Acid Oxidation Promotes Apoptotic Resistance and Proinflammatory Phenotype of CD4+ Tissue-resident Memory T cells in Crohn’s Disease

Background and aimsAs the most abundant memory T cells and major source of tumor necrosis factor α (TNF-α) in the intestinal mucosa of Crohn’s disease (CD) patients, CD4+ tissue-resident memory T (TRM) cells play a critical role in CD pathogenesis. We investigated the role of metabolic reprogramming in the regulation of proinflammatory and apoptosis-resistant phenotype for CD4+ TRM cells. MethodsCD4+ TRM cells were collected from intestinal resection tissues from control and CD patients. Transcriptomic and metabolomic analysis were performed to identify metabolic characteristics of CD4+ TRM cells. ELISA and qPCR experiments were utilized to assess cytokines level in CD4+ TRM cells, activation-induced cell apoptosis (AICD) rate was evaluated by flow cytometry. Transwell assay and wound healing assay were performed to detect the effect of CD4+ TRM cells on the migration of normal intestinal epithelial cells. ResultsTranscriptomic data combined with unbiased metabolomic analysis revealed an increased fatty acid oxidation (FAO) phenotype existed in CD4+ TRM cells from CD patients. The lipidomic data and stable isotope tracer experiments demonstrated that CD4+ TRM cells upregulated their lipid lipolysis and fatty acid uptake to fuel FAO in CD patients. Mechanistically, the activated NF-κB signaling increased transcription of genes involved in lipid lipolysis, fatty acid uptake and oxidation in CD4+ TRM cells from CD patients. Targeting FAO of CD4+ TRM cells reversed their apoptosis-resistant and proinflammatory phenotype in CD Patients. ConclusionCD4+ TRM cells process an accelerated FAO mediated by activated NF-κB signaling in CD patients, targeting FAO could reverse their apoptosis-resistant and proinflammatory phenotype. These findings shed a new light on the pathogenic mechanism investigation and novel therapy development in CD patients.

Replication of Human Sapovirus in Human-Induced Pluripotent Stem Cell-Derived Intestinal Epithelial Cells.

Sapoviruses, like noroviruses, are single-stranded positive-sense RNA viruses classified in the family Caliciviridae and are recognized as a causative pathogen of diarrhea in infants and the elderly. Like human norovirus, human sapovirus (HuSaV) has long been difficult to replicate in vitro. Recently, it has been reported that HuSaV can be replicated in vitro by using intestinal epithelial cells (IECs) derived from human tissues and cell lines derived from testicular and duodenal cancers. In this study, we report that multiple genotypes of HuSaV can sufficiently infect and replicate in human-induced pluripotent stem cell-derived IECs. We also show that this HuSaV replication system can be used to investigate the conditions for inactivation of HuSaV by heat and alcohol, and the effects of virus neutralization of antisera obtained by immunization with vaccine antigens, under conditions closer to the living environment. The results of this study confirm that HuSaV can also infect and replicate in human normal IECs regardless of their origin and are expected to contribute to future virological studies.

Inhibiting the Proliferation of Colorectal Cancer Cells by Reducing TSPO/VDAC Expression.

We aimed to explore the mechanism of the effect of remimazolam (Rem) on the proliferation of colorectal cancer (CRC) cells with CRC as a disease context. Translocation protein (TSPO) expression in CRC was determined by Western blotting and qRT-PCR in the Second Affiliated Hospital of Qiqihar Medical University from March 2019 to February 2022. TSPO-interacting proteins were predicted through string database. The proliferation was measured by CCK-8 and 5-ethynyl-2-deoxyuridine (EDU). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) and clonal colony on cells were formed to screen for the optimal concentration of Rem and to detect the viability. The expression of apoptosis-related proteins, Bcl-2 and P53, was determined by qRT-PCR and Western blotting. The effect of Rem on the expression of tumor markers, CEA and CA19-9, in CRC was examined through ELISA. TSPO expression in CRC tissues and cells was higher than that in ANT samples and normal intestinal epithelial cells. Over-expression of TSPO promoted the proliferation of HCT116 and the expression of tumor markers CEA and CA19-9 and inhibited the apoptosis of HCT116. Interference with TSPO inhibited the proliferation of HCT116 and the expression of CEA and CA19-9 and promoted the apoptosis of HCT116. 1 μg/mL Rem could inhibit the viability of HCT116, the proliferation of HCT116 and the expression of CEA and CA19-9, and improve the apoptosis of HCT116. TSPO could interact with VDAC and affect its protein expression, and Rem could inhibit the proliferation and the expression of CEA and CA19-9 through the TSPO/VDAC pathway, to promote its apoptosis. Rem affects the proliferation of CRC cells by inhibiting the TSPO/VDAC pathway.

Protective effect of total flavonoids of Engelhardia roxburghiana Wall. leaves against radiation-induced intestinal injury in mice and its mechanism.

Irradiation-induced intestinal injury (RIII) often occurs during radiotherapy in patients, which would result in abdominal pain, diarrhea, nausea, vomiting, and even death. Engelhardia roxburghiana Wall. leaves, a traditional Chinese herb, has unique anti-inflammatory, anti-tumor, antioxidant, and analgesic effects, is used to treat damp-heat diarrhea, hernia, and abdominal pain, and has the potential to protect against RIII. To explore the protective effects of the total flavonoids of Engelhardia roxburghiana Wall. leaves (TFERL) on RIII and provide some reference for the application of Engelhardia roxburghiana Wall. leaves in the field of radiation protection. The effect of TFERL on the survival rate of mice was observed after a lethal radiation dose (7.2 Gy) by ionizing radiation (IR). To better observe the protective effects of the TFERL on RIII, a mice model of RIII induced by IR (13 Gy) was established. Small intestinal crypts, villi, intestinal stem cells (ISC) and the proliferation of ISC were observed by haematoxylin and eosin (H&E) and immunohistochemistry (IHC). Quantitative real-time PCR (qRT-PCR) was used to detect the expression of genes related to intestinal integrity. Superoxide dismutase (SOD), reduced glutathione (GSH), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the serum of mice were assessed. In vitro, cell models of RIII induced by IR (2, 4, 6, 8 Gy) were established. Normal human intestinal epithelial cells HIEC-6 cells were treated with TFERL/Vehicle, and the radiation protective effect of TFERL on HIEC-6 cells was detected by clone formation assay. DNA damage was detected by comet assay and immunofluorescence assay. Reactive oxygen species (ROS), cell cycle and apoptosis rate were detected by flow cytometry. Oxidative stress, apoptosis and ferroptosis-related proteins were detected by western blot. Finally, the colony formation assay was used to detect the effect of TFERL on the radiosensitivity of colorectal cancer cells. TFERL treatment can increase the survival rate and time of the mice after a lethal radiation dose. In the mice model of RIII induced by IR, TFERL alleviated RIII by reducing intestinal crypt/villi structural damage, increasing the number and proliferation of ISC, and maintaining the integrity of the intestinal epithelium after total abdominal irradiation. Moreover, TFERL promoted the proliferation of irradiated HIEC-6 cells, and reduced radiation-induced apoptosis and DNA damage. Mechanism studies have found that TFERL promotes the expression of NRF2 and its downstream antioxidant proteins, and silencing NRF2 resulted in the loss of radioprotection by TFERL, suggesting that TFERL exerts radiation protection by activating the NRF2 pathway. Surprisingly, TFERL reduced the number of clones of colon cancer cells after irradiation, suggesting that TFERL can increase the radiosensitivity of colon cancer cells. Our data showed that TFERL inhibited oxidative stress, reduced DNA damage, reduced apoptosis and ferroptosis, and improved IR-induced RIII. This study may offer a fresh approach to using Chinese herbs for radioprotection.

LINC00460 contributes to colorectal cancer cell invasion

ABSTRACT Research background: Colorectal cancer (CRC) is one of the most prevalent malignant tumors in the world. Research on long noncoding RNAs (LncRNAs) may illuminate tumorigenesis and progression of CRC. Methods: We screened long non-coding RNA LINC00460 as a new candidate, which promoted the development of CRC in two independent datasets (GSE39582 and GSE21510) from the Gene Expression Omnibus (GEO). In 98 CRC tissues, expression levels of LINC00460 were significantly increased in cancerous tissues compared to paired adjacent normal tissues (P < 0.001). In addition, in the most common CRC cell lines. LINC00460 expression was up-regulated compared to normal human intestinal epithelial cell line NCM460. siRNA was transfected into CRC cell lines. LINC00460 knockdown reduced cell invasion ability and did not affect cell proliferation. The association between LINC00460 expression and clinical pathological features and prognosis were also analyzed. Results: This increased expression was found to significantly correlate with lymph node metastasis (P = 0.002), distant metastasis (P = 0.045) and TNM stage (P < 0.001); but not related to age, gender, location of tumor, and histological grade. The overall survival (OS) in CRC patients with overexpression of LINC00460 was inferior to that with low expression (P = 0.0167). Multivariate Cox regression analyses indicated that LINC00460 expression, as well as TNM stage was an independent prognostic risk factor for patients with CRC. Conclusion: These results showed that a higher expression level of LINC00460 might play an oncogenic role in colorectal cancer invasion and metastasis. It also proved that LINC00460 might be used as a potential diagnostic and prognostic biomarker in CRC patients.

The effect of 1,25-dihydroxyvitamin D3 on the Wnt signaling pathway in bovine intestinal epithelial cells is mediated by the DKK2 (dickkopf2) Wnt antagonist

The Wnt/β-catenin signaling pathway is aberrantly activated in most colorectal cancers. High-dose 1,25(OH)2D3 has anticancer effect by regulating Wnt signal pathway. However, it is not clear whether high-dose of 1,25(OH)2D3 have an effect on normal cells. The aim of the present study was to investigate the mechanism of high-dose 1,25(OH)2D3 on the Wnt signaling pathway in bovine intestinal epithelial cells. The potential mechanism of action was investigated after knockdown and overexpression of the Wnt pathway inhibitor, DKK2, in intestinal epithelial cells by observing the effects of 1,25(OH)2D3 on proliferation, apoptosis, pluripotency and the expression of genes related to the Wnt/β-catenin signaling pathway. In the present study, we introduced the method of isolation and culture of primary bovine intestinal epithelial cells. After cells were treated with 50 ng/mL 1,25(OH)2D3 or DMSO for 48 h, total RNA was extracted, and six differentially expressed genes, including SERPINF1, SFRP2, SFRP4, FZD2, WISP1 and DKK2 were identified by transcriptome sequencing, which were related to Wnt signaling pathway. To further explore the mechanism of 1,25(OH)2D3 on the Wnt/β-catenin signaling pathway, we constructed knockdown and overexpression plasmids of DKK2. After transfecting these plasmids into bovine intestinal epithelial cells, we measured the expression of DKK2 mRNA and protein through GFP expression, qRT-PCR and western blot analyses to verify the transfection efficiency. In addition, the CCK-8 assay was used to detect the cell proliferation rate after transfection. Subsequently, the transfected cells were treated with 1,25(OH)2D3 for 48 h, and the proliferation- (Ki67 and PCNA), apoptosis- (Bcl-2, p53, casp3 and casp8), pluripotency- (Bmi-1, Lrig1, KRT19 and TUFT1) and Wnt/ β-catenin signaling pathway- related genes (LGR5, DKK2, VDR, β- Catenin, SFRP2, WISP1 and FZD2) were detected by qRT-PCR and western blot analyses. Our results showed that the expression trend of some genes in bovine intestinal epithelial cells under high-dose 1,25(OH)2D3 was consistent with the sequencing results, including SFRP2 (P < 0.001), SFRP4 (P < 0.05), FZD2 (P < 0.01), WISP1 (P < 0.001) and DKK2 (P < 0.001). In addition, knockdown of DKK2 inhibited cell proliferation (P < 0.01), but DKK2 overexpression promoted cell proliferation (P < 0.01). Compared to the control group, 1,25(OH)2D3 promoted the expression of Wnt/β-catenin signaling pathway-related proteins in bovine intestinal epithelium, thus maintaining intestinal homeostasis in normal intestinal epithelium. In addition, knockdown and overexpression of DKK2 indicated that 1,25(OH)2D3 weakened the inhibitory effect of DKK2 on the Wnt/β-catenin signaling pathway. Together, these results suggest that high-dose 1,25(OH)2D3 has no killing effect on normal intestinal epithelial cells and regulates Wnt/β-catenin signaling pathway through DKK2.

Adhesive cryogel particles for bridging confined and irregular tissue defects

BackgroundReconstruction of damaged tissues requires both surface hemostasis and tissue bridging. Tissues with damage resulting from physical trauma or surgical treatments may have arbitrary surface topographies, making tissue bridging challenging.MethodsThis study proposes a tissue adhesive in the form of adhesive cryogel particles (ACPs) made from chitosan, acrylic acid, 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The adhesion performance was examined by the 180-degree peel test to a collection of tissues including porcine heart, intestine, liver, muscle, and stomach. Cytotoxicity of ACPs was evaluated by cell proliferation of human normal liver cells (LO2) and human intestinal epithelial cells (Caco-2). The degree of inflammation and biodegradability were examined in dorsal subcutaneous rat models. The ability of ACPs to bridge irregular tissue defects was assessed using porcine heart, liver, and kidney as the ex vivo models. Furthermore, a model of repairing liver rupture in rats and an intestinal anastomosis in rabbits were established to verify the effectiveness, biocompatibility, and applicability in clinical surgery.ResultsACPs are applicable to confined and irregular tissue defects, such as deep herringbone grooves in the parenchyma organs and annular sections in the cavernous organs. ACPs formed tough adhesion between tissues [(670.9 ± 50.1) J/m2 for the heart, (607.6 ± 30.0) J/m2 for the intestine, (473.7 ± 37.0) J/m2 for the liver, (186.1 ± 13.3) J/m2 for muscle, and (579.3 ± 32.3) J/m2 for the stomach]. ACPs showed considerable cytocompatibility in vitro study, with a high level of cell viability for 3 d [(98.8 ± 1.2) % for LO2 and (98.3 ± 1.6) % for Caco-2]. It has comparable inflammation repair in a ruptured rat liver (P = 0.58 compared with suture closure), the same with intestinal anastomosis in rabbits (P = 0.40 compared with suture anastomosis). Additionally, ACPs-based intestinal anastomosis (less than 30 s) was remarkably faster than the conventional suturing process (more than 10 min). When ACPs degrade after surgery, the tissues heal across the adhesion interface.ConclusionsACPs are promising as the adhesive for clinical operations and battlefield rescue, with the capability to bridge irregular tissue defects rapidly.