The purpose of this study was to verify the effect of berberine (BBR) on endoplasmic reticulum stress (ERS) and apoptosis of intestinal epithelial cells (IECs) in mice with ulcerative colitis (UC). BALB/c mice were randomly divided into five groups as follows: blank control, model, and low-, medium-, and high-dose BBR. A dextran sodium sulfate- (DSS-) induced model of UC was prepared, and the low-, medium-, and high-dose BBR groups were simultaneously gavaged with a BBR suspension for 7 d. Disease activity index (DAI) was assessed, and tissue damage index (TDI) was assessed from colon samples after the last administration. TUNEL assays were used to detect apoptosis of IECs. Immunohistochemistry and/or real-time PCR were applied to determine the expression of GRP78, caspase-12, and caspase-3. In all BBR treatment groups, clinical symptoms of colitis and histopathological damage were significantly reduced. The high-dose BBR group exhibited particularly pronounced decrease (p<0.01) in both DAI (0.48 ± 0.36) and TDI (1.62 ± 0.64) relative to the model group (1.50 ± 0.65 and 3.88 ± 0.04, respectively). In colon tissues of the model group, the number of apoptotic IECs was significantly increased; the expression of GRP78, caspase-12, and caspase-3 proteins was significantly increased; and the expression of the GRP78 mRNA was upregulated. In low-, medium-, and high-dose BBR groups, the number of apoptotic IECs was significantly reduced. Moreover, GRP78 and caspase-3 expression levels were significantly decreased in the medium- and high-dose BBR groups, caspase-12 expression was significantly decreased in the high-dose BBR group, and the GRP78 mRNA expression level was significantly decreased in the high-dose BBR group. BBR can effectively reduce the rate of IEC apoptosis in UC mice and alleviate the inflammatory response in the colon. The underlying mechanism seems to involve ERS modulation and inhibition of ERS-mediated activation of the caspase-12/caspase-3 apoptosis signaling pathway.

Dysfunction of intestinal epithelial cells (IECs) leads to intestinal epithelial barrier damage and critically involves in the pathogenesis and development of ulcerative colitis (UC). Accumulating studies revealed essential functions of non-coding RNAs in UC. LncRNA NEAT1 (long non-coding RNA nuclear paraspeckle assembly transcript 1) is frequently dysregulated in diverse human diseases. Currently, the precise roles of NEAT1 in the dysfunction of IECs during UC remain unclear. We report NEAT1 was significantly upregulated in IECs from UC patients. In addition, microRNA-410-3p was remarkedly suppressed in IECs from UC patients. Silencing NEAT1 effectively ameliorates the LPS-induced IECs dysfunction. Bioinformatical analysis, RNA pull-down and luciferase assays illustrated that NEAT1 sponged miR-410-3p to downregulate its expression in IECs. Interestingly, the glucose metabolism was obviously elevated in IECs from UC compared with normal colon tissues. Furthermore, NEAT1 promoted and miR-410-3p suppressed glucose metabolism of IECs. We identified lactate dehydrogenase A (LDHA), a glucose metabolism key enzyme, was a direct target of miR-410-3p in IECs. Rescue experiments verified that restoration of miR-410-3p in NEAT1-overexpressing IECs successfully overcame the NEAT1-promoted cell death under LPS treatment by targeting LDHA. In summary, these results unveiled new roles and molecular mechanisms for the NEAT1-mediated IECs dysfunction during the ulcerative colitis.

Background Colorectal cancer (CRC) is a fatal malignant tumor with poor prognosis. Cancer stem cells (CSCs) can cause metastasis, recurrence and drug resistance in CRC. This research aimed to analyze stemness‐related prognostic genes of CRC based on single‐cell RNA‐sequencing (scRNA‐seq) data. Methods DESeq2 was applied to analyze the differentially expressed genes (DEGs). The mRNA stemness index (mRNAsi) was calculated by one‐class logistic regression (OCLR). The stemness‐related cells were analyzed based on scRNA‐seq dataset GSE166555. Monocle 2 algorithm was used for stemness‐related cells pseudotime trajectory analysis. The stemness‐related prognostic genes were analyzed by clusterProfiler and survival package. The stemness of CRC cells was detected by spheroid formation assay, and the expression of stemness‐related prognostic genes was verified by qRT‐PCR and Western blot. Results 7916 DEGs between the CRC and normal tissues were obtained. The mRNAsi of the CRC tissues was shown to be significantly higher than that of the normal tissues. 7 and 8 cell types were annotated respectively in the normal and CRC tissues through analysis of the scRNA‐seq data. Cell–cell interactions (CCIs) in the tumor tissues were revealed to be significantly enhanced than that in the normal tissues. By calculating the ‘stemness score’, CSCs, epithelial cells (EPCs) and cancer‐associated fibroblasts (CAFs) were defined as stemness‐related cells. Through pseudotime trajectory analysis, 2111 genes were identified as state 2‐specific genes. Then, 41 genes were obtained by taking intersection of the up‐regulated genes with state 2‐specific genes and marker genes of CSCs, EPCs and CAFs. The univariate COX regression analysis revealed 5 stemness‐related prognostic genes (TIMP1, PGF, FSTL3, SNAI1 and FOXC1). Kaplan–Meier curve analysis indicated that the higher the expression of 5 genes, the lower the survival rate. In vitro cell experiment confirmed that the expression of TIMP1, PGF and SNAI1 was consistent with that revealed by bioinformatics analysis. Conclusions TIMP1, PGF and SNAI1 were identified as stemness‐related prognostic genes of CRC, and possibly potential therapeutic targets for CRC.

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The etiology and pathogenesis of ulcerative colitis (UC) remain unclear. Therefore, we observed the activation and transduction of the protein kinase RNA-like endoplasmic reticulum kinase (PERK)–eukaryotic initiation factor 2α (eIF2α)–C/EBP homologous protein (CHOP) signaling axis from the perspective of endoplasmic reticulum stress (ERS) and explored the pathogenesis of UC. Cell survival rate, apoptosis rate, cycle distribution, cell permeability, ultrastructural changes in the ER, and the expression and transcription of key genes and proteins were detected. A UC mouse model was induced using dextran sulfate sodium. The disease activity index, tissue damage index, intestinal epithelial cell apoptosis, serum D-lactate, and diamine oxidase contents were determined. Blocking the PERK and CHOP nodes in the PERK–eIF2α–CHOP signaling axis increased stressed cell survival rate, G2 cell proportion, and monolayer cell transmembrane electrical impedance, but decreased the apoptosis rate and fluorescein isothiocyanate dextran content, so the ER structure could be alleviated. Treatment with 5-aminosalicylic acid significantly improved intestinal and systemic symptoms, and colonic mucosal damage was relieved. p-PERK, p-eIF2α, activating transcription factor 4, and CHOP gene transcription levels were higher in stressed cells than in normal cells, and 5-aminosalicylic acid reduced the expression of these proteins. Intestinal epithelial cells experience excessive ERS during UC, and the stress signal is successively transmitted to the apoptosis marker protein CHOP along the signal axis. Targeted blockage of the PERK–eIF2α–CHOP signaling axis may be an effective treatment strategy for UC.