Colonic mucin-2 attenuates acute necrotizing pancreatitis in rats by modulating intestinal homeostasis.

Mucin-2 (MUC2) secreted by goblet cells participates in the intestinal barrier, but its mechanism in acute necrotizing pancreatitis (ANP) remains unclear. In acute pancreatitis (AP) patients, the functions of goblet cells (MUC2, FCGBP, CLCA1, and TFF3) decreased, and MUC2 was negatively correlated with AP severity. ANP rats treated with pilocarpine (PILO) (PILO+ANP rats) to deplete MUC2 showed more serious pancreatic and colonic injuries, goblet cell dysfunction, gut dysbiosis, and bacterial translocation than those of ANP rats. GC-MS analysis of feces showed that PILO+ANP rats had lower levels of butyric acid, isobutyric acid, isovaleric acid, and hexanoic acid than those of ANP rats. The expression of MUC2 was associated with colonic injury and gut dysbiosis. All these phenomena could be relieved, and goblet cell functions were also partially reversed by MUC2 supplementation in ANP rats. TNF-α-treated colonoids had exacerbated goblet cell dysfunction. MUC2 expression was negatively correlated with the levels of pro-inflammatory cytokines (IL-1ß and IL-6) (p < .05) and positively related to the expression of tight junction proteins (Claudin 1, Occludin, and ZO1) (p < .05). Downregulating MUC2 by siRNA increased the levels of the pro-inflammatory cytokines in colonoids. MUC2 might maintain intestinal homeostasis to alleviate ANP.

Transpapillary Stenting Improves Treatment Outcomes in Patients Undergoing Endoscopic Transmural Drainage of Ductal Disruption-Associated Pancreatic Fluid Collections.

INTRODUCTION: Endoscopic transmural drainage (TMD) has been accepted as the preferred therapy for symptomatic pancreatic fluid collections (PFCs). Recurrence of PFCs presents a unique challenge in patients with disrupted pancreatic duct (PD). We aimed to evaluate whether transpapillary drainage (TPD) provides additional benefits to TMD in patients with PD disruption. METHODS: This was a multicenter retrospective study. Consecutive patients who underwent TMD, TPD, or combined drainage (CD) of PFCs were included. The primary outcome was to compare PFC recurrence among different groups. The secondary outcomes were the technical success rate, length of hospital stay, and procedure-related complications. RESULTS: A total of 153 patients, which consists of 57 patients with pancreatic pseudocysts and 96 patients with walled-off necrosis, were included. PFC recurrence was more common in patients with PD disruption than those with an intact main duct (19% vs 1.4%, P < 0.001). PD disruption was identified as a major risk factor of PFC recurrence by univariable and multivariable analyses. The recurrence rate of CD was significantly lower than TMD only or TPD only (6.5% vs 15.4% vs 22.7%, P < 0.01). The length of hospital stay of CD was significantly shorter than TMD only or TPD only (5 [3.0-9.0] vs 7.0 [5.0-12.0] vs 9 [7.0-16.0], P < 0.001). Dual-modality drainage did not increase procedure-related complications compared with TMD only (13.0% vs 12.8%, P > 0.05). Partial PD disruption was bridged in 87.3% cases while complete PD disruption was reconnected in 55.2% cases. Although statistically not significant, the clinical success rate in walled-off necrosis cases with actively bridged ducts was much higher than those with passively bridged ducts (76.9% vs 40%). DISCUSSION: Transpapillary pancreatic duct stenting seems to improve the efficacy of endoscopic TMD of pancreatic duct disruption-associated PFCs by reducing the recurrence rate and shortening the length of hospital stay.

The oncogenic miR-27a/BTG2 axis promotes obesity-associated hepatocellular carcinoma by mediating mitochondrial dysfunction.

Obesity is closely related to the initiation and development of hepatocellular carcinoma (HCC). The regulatory mechanism of obesity-associated HCC remains unclear. HepG2 cells treated with palmitic acid (PA) and diethylnitrosamine (DEN)-induced HCC mice fed a high-fat diet (HFD) were established. The expression of miR-27a and B-cell translocation gene 2 (BTG2) mRNA and protein were detected via qPCR and western blotting. Prediction software and luciferase assays were employed to verify the miR-27a/BTG2 axis. The biological effects of HepG2 cells were evaluated with ORO staining, MTT assays, Transwell assays, Mito-Timer, and Mito-SOX staining. Significantly upregulated miR-27a and downregulated BTG2 mRNA and protein were observed in HepG2 cells and liver tissues of HCC mice. Overexpressing miR-27a (mi-miR-27a) markedly promoted cellular lipid accumulation, proliferation, and invasion, accompanied by aggravated mitochondrial dysfunction (increased fading and ROS products of mitochondria) in HepG2 cells. Additionally, these effects were further reinforced in HepG2 cells treated with mi-miR-27a and PA. BTG2 was identified as a direct target and was negatively regulated by miR-27a. Similarly, BTG2 knockdown (sh-BTG2) had effects identical to those of mi-miR-27a on HepG2 cells. Additionally, PA evidently enhanced these effects of sh-BTG2 in HepG2 cells. Moreover, BTG2 overexpression effectively reversed the effects of miR-27a, including lipotropic and oncogenic effects, and simultaneously promoted mitochondrial imbalance in HepG2 cells. Thus, obesity-associated miR-27a acts as an oncogene to promote lipid accumulation, proliferation, and invasion by negatively regulating BTG2-mediated mitochondrial dysfunction in HCC.

Deoxycholic acid-stimulated macrophage-derived exosomes promote spasmolytic polypeptide-expressing metaplasia in the stomach.

RATIONALE: Spasmolytic polypeptide-expressing metaplasia (SPEM) is an important risk factor for the occurrence of gastric cancer. It may be driven by a chronic inflammatory environment in which macrophage is involved. Studies have shown that intestinal metaplasia may originate from SPEM, and bile acid-induced chronic inflammation plays an important role in the process of intestinal metaplasia. However, whether bile acids are involved in the development of SPEM and the specific mechanism are unclear. Meanwhile, macrophages are known to be involved in inflammation regulation by releasing various factors, including exosomes. In this study, we hypothesized that the exosomes released from macrophages stimulated by deoxycholic acid participated in the development of SPME. METHODS: In vivo, mice were gavaged with deoxycholic acid for 4 weeks, and gastric tissues were harvested. In vitro, deoxycholic acid-induced macrophage-derived exosomes were isolated by ultracentrifugation and cocultured with the gastric organoids of mice. Immunofluorescence staining and quantitative real-time PCR were used to analyze markers of macrophages and SPEM. RESULTS: In vivo, after 4 weeks of deoxycholic acid intragastric administration, macrophage markers (F4/80) and SPEM markers (TFF2 and GSII lectin) were increased in from treated mice compared with those from normal control mice. In vitro, macrophage-derived exosomes labeled with PKH67 were internalized by gastric organoids. Deoxycholic acid-induced macrophage-derived exosomes increased the expression of SPEM markers (TFF2 and GSII lectin) in gastric organoids compared to exosomes derived from macrophages without deoxycholic acid stimulation. CONCLUSION: Macrophage-derived exosomes may be a novel mechanism by which deoxycholic acid promotes SPEM.

linc-SCRG1 accelerates liver fibrosis by decreasing RNA-binding protein tristetraprolin.

The biologic roles of long noncoding RNAs (lncRNAs) in liver fibrosis remained unknown. Through microarray analysis, linc-SCRG1 (a lncRNA with transcript length 3118 bp) was found up-regulated 13.62-fold in human cirrhotic tissues. Quantitative PCR verified that linc-SCRG1 increased along with liver fibrosis progression in human tissues and in activated LX2 cells induced by TGF-ß1. Knockdown of linc-SCRG1 significantly reversed the effects of TGF-ß1 on LX2, including inhibiting activation, promoting apoptosis, reducing proliferation, lessening invasion, and down-regulating genes [fibrosis-related mRNA: α-smooth muscle actin ( α-SMA), type I collagen, and B-cell lymphoma-2; invasion-related mRNA: matrix metallopeptidase-2 ( MMP-2), MMP-9, and MMP-13; inflammation-related mRNA: TNF-α, IL-6, and IL-10]. linc-SCRG1 had binding sites with tristetraprolin (TTP), a kind of RNA-binding protein, and specifically combined to TTP proteins. Overexpression of linc-SCRG1 would cause TTP mRNA unstably and proteins decreasing. TTP mRNA was proved having negative relevance with linc-SCRG1 and was gradually reduced during human liver fibrosis progression. Overexpressing TTP resulted in knockdown of lincSCRG1 and degraded downstream target genes ( MMP-2 and TNF-α) in activated LX2. Overexpressing TTP had the same effects as small interfering RNA-lincSCRG1 (si- lincSCRG1), whereas knockdown of TTP had reversal effects on si- lincSCRG1 in activated LX2. In summary, linc-SCRG1 reduced TTP and restricted its degradation of target genes TNF-α and MMP-2. Therefore, linc-SCRG1 had a repressing TTP-elicited inactivation effect on hepatic stellate cell (HSC) phenotypes. Inhibition of linc-SCRG1 may be a novel therapeutic approach to inactivate HSCs and extenuate human liver fibrosis.-Wu, J.-C., Luo, S.-Z., Liu, T., Lu, L.-G., Xu, M.-Y. linc-SCRG1 accelerates liver fibrosis by decreasing RNA-binding protein tristetraprolin.

Endoscopic acanthosis nigricans appearance: A novel specific marker for diagnosis of low-grade intraepithelial neoplasia.

BACKGROUND AND AIM: At present, there is no recognized diagnostic criteria for gastric low-grade intraepithelial neoplasia (LGIN). The purpose of this study was to determine whether an "endoscopic acanthosis nigricans appearance (EANA)" could be a useful endoscopic marker for distinguishing LGIN lesions from peripheral non-neoplastic tissues. METHODS: A retrospective study was conducted on 638 cases of suspected superficial lesions with endoscopic images from white light endoscopy and magnifying endoscopy combined with narrow band imaging. According to the pathological results of accurate biopsies, those lesions were divided into three groups: a control group, an LGIN group, and an early gastric cancer (EGC) group. RESULTS: According to the presence of EANAs, the sensitivity, specificity, positive predictive value, and negative predictive value for differentiating between the LGIN and control groups were 24.8%, 97.3%, 78.3%, and 76.6%, respectively. The sensitivity (84.1%) and negative predictive value (92.4%) were significantly improved by combining EANA with types IV-VI pit pattern. The intervening part and mean gray value of glands, representing microsurface features and microvascular variation, were significantly larger or higher in EANA lesions than in the surrounding non-neoplastic mucosa. LGIN with EANA was more likely to be present in lesions of type 0-IIa. In addition, the prevalence of EANAs in EGC was 16.7%. CONCLUSION: An EANA could be used as an auxiliary indicator for a diagnosis of LGIN in suspected lesions. It could also play a potential assistive role in the diagnosis of EGC lesions.

Characterization of the duodenal bacterial microbiota in patients with pancreatic head cancer vs. healthy controls.

An increasing number of reports have demonstrated that there is an association between the presence of pathogenic microorganisms and pancreatic cancer. However, the role of the duodenal microbiota in pancreatic carcinogenesis remains unknown. In this study, duodenal mucosal microbiota was analyzed in 14 patients with pancreatic head cancer and 14 healthy controls using 16S rRNA gene pyrosequencing methods. Plasma endotoxin activity and the concentrations of the proinflammatory cytokine IL-6 and C-reactive protein (CRP) were measured in blood samples. The urea breath test was used to detect Helicobacter pylori infections. Endoscopic duodenal mucosal biopsies were evaluated by histological examinations. Statistical comparisons of inflammatory factors revealed significantly higher levels of CRP and IL-6 in the pancreatic cancer group as compared to healthy controls. Patients with pancreatic cancer also had a higher incidence of H. pylori infections and showed mucosal changes, including villous abnormalities and diffuse inflammatory cell infiltration in the lamina propria. The sequences analysis showed that based on linear discriminant analysis effect size (LEfSe) analysis at the genus level, Acinetobacter, Aquabacterium, Oceanobacillus, Rahnella, Massilia, Delftia, Deinococcus, and Sphingobium were more abundant in the duodenal mucosa of pancreatic cancer patients, whereas the duodenal microbiotas of healthy controls were enriched with Porphyromonas, Paenibacillus, Enhydrobacter, Escherichia, Shigella, and Pseudomonas. These results reveal a picture of duodenal microbiota in pancreatic head cancer patients that could be useful in future trials investigating the role of gut microbiota in pancreatic cancer.

[Reversal of liver fibrosis through AG490 inhibitor-mediated inhibition of the TGFbeta1-STAT3 pathway].

OBJECTIVE: To investigate the role of TGF-beta1 and STAT3 signaling in liver fibrosis using a rat model system and to determine the therapeutic mechanism of AG490 in relation to this signaling pathway. METHODS: Rats were randomly divided into a control group and DENA-induced liver fibrosis model group, and then subdivided into AG490 treatment groups. During fibrosis development, liver tissue samples were collected at different time points (0, 4 and 8 weeks) and evaluated according to the Scheuer scoring system. Expression of STAT3, TGFbeta1, alpha-SMA, E-cadherin, MMP2 and TIMP1 was measured by PCR (mRNA) and immunohistochemistry and western blotting (protein). RESULTS: Increasing degrees of inflammation and fibrosis were observed in liver tissues of DENA-treated rats throughout model establishment. The mRNA expression of TGFbeta1 and STAT3 was significantly increased in DENA-induced rats with advanced fibrosis (AF) compared to those with early fibrosis (EF) (P = 0.034 and P = 0.012 respectively). The protein expression of TGF-beta1, phospho-Smad2, alpha-SMA, E-cadherin, STAT3 and phospho-STAT3 was significantly increased in DENA-induced rats with AF compared to the unmodeled control group (P = 0.048, P = 0.003, P = 0.002, P = 0.028, P = 0.009 and P = 0.039). The protein expression of E-cadherin was lower in the DENA-induced rats with AF than in those with EF (P = 0.026). STAT3 and TGF-beta1 co-expression was detected in AF tissues. DENA-induced AG490-treated rats with AF showed substantially lower protein expression of STAT3, TGF-beta1, MMP2 and TIMP1 compared to DENA-induced untreated rats with AF (P = 0.006, P = 0.018, P = 0.010 and P = 0.005); in addition, the degrees of fibrosis and inflammation were also greatly reduced in the DENA-induced AG490-treated rats with AF compared to DENA-induced untreated rats with AF (P = 0.042 and P = 0.021). Conclusions STAT3 signal transduction may regulate the TGF-beta1 pathway and affect liver fibrosis, especially in the advanced phase. AG490 can inhibit TGFbeta1-STAT3 signaling, resulting in reversal of liver fibrosis.

Combining brushing cytology with simultaneous vacuum aspiration in suspicious biliopancreatic malignancies: A multicenter propensity score-matched study (with video).

BACKGROUND: Brush cytology during endoscopic retrograde cholangiopancreatography (ERCP) is a standard approach in diagnosing biliopancreatic strictures, with yet unsatisfying sensitivity. AIMS: We brought additional simultaneous vacuum aspiration to brushing process and re-evaluate the diagnostic performance. METHODS: This multi-centered retrospective study was conducted in three tertiary centers. Consecutive patients with biliopancreatic strictures were identified. The patients were divided into two arms: the conventional arm (CA) receiving general brushing approach, and the modified arm (MA) being treated with additional vacuum aspiration when performing bushing. The 1:1 propensity-score matching was implemented to tackle the selective biases. RESULTS: A total of 555 patients were identified and 200 patient pairs (193 males, 207 females, with a mean age of 68.1 ± 13.1 years.) fell into the ultimate evaluation. A final diagnosis of malignant stricture was established in 243 patients. The diagnostic yield of the MA group was substantially better than that of the CA group, whether "suspicious malignancies" were considered malignancies or not. The rates of sensitivity, specificity and accuracy were 46.2%, 100%, 68.0% in the MA group, and 15.3%, 98.7%, and 47.0% in the CA group respectively. CONCLUSIONS: Brushing accompanied by simultaneous vacuum aspiration at ERCP improves the diagnostic yield in suspicious biliopancreatic malignancies.

Endoscopic sphincterotomy associated cholangitis in patients receiving proximal biliary self-expanding metal stents.

BACKGROUND: Endoscopic biliary stent placement during the procedure of endoscopic retrograde cholangiopancreatography (ERCP) is preferred to provide biliary drainage for unresectable malignant biliary obstruction. There is considerable controversy over the use of endoscopic sphincterotomy (ES) prior to stent placement. This study aimed to determine whether ES before intraductal self-expanding metal stent (SEMS) placement affects the clinical outcome and complications in patients with proximal malignant obstructive biliary diseases. METHODS: In a prospective randomized controlled trial, 82 patients with inoperable malignant biliary strictures were randomly assigned to biliary stenting groups with or without ES. Resolution of jaundice and the incidence of complications including acute cholangitis, pancreatitis and stent occlusion within 6 months were evaluated. RESULTS: SEMSs were successfully deployed in all patients, resulting in clinical and biochemical improvement of obstructive symptoms in both groups. The incidence of cholangitis was higher in the ES group than in the non-ES group (58.5% vs 31.7%, P=0.015). The interval between stent placement and the first acute cholangitis was much shorter in the ES group than in the non-ES group (P=0.024). The use of ES increased the incidence of cholangitis (P=0.004, risk ratio, 8.196). The rate of post-ERCP pancreatitis after stent placement was greater in the non-ES group than in the ES group (31.7% vs 9.8%, P=0.014). No significant differences were found in the rate of restenosis and the mortality rate between the two groups. CONCLUSIONS: ES prior to intraductal SEMS placement was associated with an increased incidence of acute cholangitis. ES should be carefully evaluated prior to its use in patients with proximal malignant obstructive biliary diseases.

Paneth Cells Protect against Acute Pancreatitis via Modulating Gut Microbiota Dysbiosis.

Acute pancreatitis (AP) is usually accompanied by intestinal failure, but its mechanism is still unclear. In AP patients, the functions of Paneth cells (lysozyme, HD5, Reg3γ, and Wnt3a) decreased. Compared with AP mice, injuries and inflammation of the pancreas and ileum were aggravated in AP mice treated with dithizone (Dith) (Dith+AP mice). Intestinal permeability and bacterial translocation were also increased. 16S rRNA sequencing showed that the gut microbiota of Dith mice and Dith+AP mice exhibited a marked increase in the pathogenic bacterium Helicobacter and a significant decrease in the probiotic bacterium Blautia. Lysozyme gavage in Dith+AP mice effectively alleviated injuries of the pancreas and small intestine. The beneficial effect of lysozyme was associated with a significant increase in the probiotic bacterium Blautia and a virtual absence of the pathogenic bacterium Helicobacter. The severity of AP in antibiotic-treated mice (ABX mice) was significantly aggravated when receiving feces from Dith mice and was markedly alleviated when receiving feces from lysozyme-gavaged mice. In vitro, lysozyme increased the proliferation of enteroids by promoting the activation of the Wnt pathway and Lgr5 expression in intestinal stem cells. IMPORTANCE We demonstrate that AP patients and experimental AP mice exhibited a dysfunction of Paneth cells. Our in vivo research showed that the severity of AP was exacerbated by the long-term dysfunction of Paneth cells, which was associated with gut microbiota disorder. Restoring part of Paneth cell functions through lysozyme supplementation alleviated the severity of AP and gut microbiota dysbiosis. This study provides novel insight into the link of pancreas-gut interactions in the pathogenesis of AP, providing a new direction for the clinical treatment of intestinal complications during AP.

Hepatocyte-derived exosomal miR-27a activateshepatic stellate cells through the inhibitionof PINK1-mediated mitophagy in MAFLD.

The role of exosome-mediated mitophagy in the crosstalk between hepatocytes (HCs) and hepatic stellate cells (HSCs) in metabolic-associated fatty liver disease (MAFLD) remains unknown. Serum exosomal miR-27a levels were markedly increased and positively correlated with liver fibrosis in MAFLD patients and mice. Exosomal miR-27a was released from lipotoxic HCs and specifically transmitted to recipient-activated HSCs. PINK1, the key target of miR-27a, primarily mediates mitophagy. Overexpression of miR-27a or knockdown of PINK1 or lipotoxic HC-exosomal miR-27a impaired mitochondria (inhibiting mitophagy, respiration, membrane potential, and transcription while promoting reactive oxygen species production) in activated HSCs and stimulated HSC-derived fibroblasts (promoting activation and proliferation while inhibiting autophagy). High exosomal miR-27a serum levels and a lack of hepatic PINK1-mediated mitophagy were directly related to liver fibrosis in MAFLD mice. Lipotoxic HC exosome transplantation aggravated the degree of PINK1-mediated mitophagy suppression, steatohepatitis, lipidosis, and fibrosis in the livers of MAFLD mice with cirrhosis. Both in vitro and in vivo, exosomes derived from miR-27a-knockdown HCs could not facilitate the abovementioned deteriorating effects. In conclusion, lipotoxic HC-exosomal miR-27a plays a pivotal role in inhibiting mitophagy and in promoting MAFLD-related liver fibrosis by negatively regulating PINK1 expression.

Linc-SCRG1 accelerates progression of hepatocellular carcinoma as a ceRNA of miR26a to derepress SKP2.

BACKGROUND: Increasing evidence has demonstrated that long noncoding RNAs (lncRNAs) have regulatory functions in hepatocellular carcinoma (HCC). The link between lincSCRG1 and HCC remains unclear. METHODS: To explore the lincSCRG1 regulation axis, bioinformatics, RIP and luciferase reporter assay were performed. The expressions of lincSCRG1-miR26a-SKP2 were detected in HCC tissues and cell lines through qPCR and western blot. The functions of HCC cells were investigated through in vitro assays (MTT, colony formation, transwell and flow cytometry) and the inner effect of lincSCRG1-miR26a in vivo was evaluated by xenografts and liver metatstatic nude mice models. RESULTS: LincSCRG1 was found to be strongly elevated in human HCC tissues and cell lines. MiR26a and S phase kinase-related protein 2 (SKP2) were predicted as the target miRNA for lincSCRG1 and the target gene for miR26a with direct binding sites, respectively. LincSCRG1 was verified as a competing endogenous RNA (ceRNA) via negative regulation of miR26a and derepression of SKP2 in HCC cells. Both overexpression of lincSCRG1 (ov-lincSCRG1) and inhibition of miR26a (in-miR26a) obviously stimulated cellular viability, colony formation, migration and proliferation of S phase cells and also significantly increased the protein levels of cyclinD1, CDK4, MMP2/3/9, Vimentin, and N-cadherin or inhibited the protein level of E-cadherin of HCC cells, while knockdown of lincSCRG1 (sh-lincSCRG1) and upregulation of miR26a (mi-miR26a) had the opposite effects on HCC cells. Cotransfection of in-miR26a or overexpression of SKP2 (ov-SKP2) with sh-lincSCRG1 could rescue the anticancer functions of sh-lincSCRG1, including suppressing proliferation and migration of HCC cells. Additionally, sh-lincSCRG1 could effectively inhibit the growth of subcutaneous xenograft tumours and lung metastasis, while the anticancer effect of sh-lincSCRG1 could be reversed by cotransfection of in-miR26a. CONCLUSIONS: LincSCRG1 acts as a ceRNA of miR26a to restrict its ability to derepress SKP2, thereby inducing the proliferation and migration of HCC cells in vitro and in vivo. Depletion of lincSCRG1 could be used as a potential therapeutic approach in HCC.

Lipotoxic hepatocyte-derived exosomal miR-1297 promotes hepatic stellate cell activation through the PTEN signaling pathway in metabolic-associated fatty liver disease.

BACKGROUND: Exosomes play an important role in metabolic-associated fatty liver disease (MAFLD), but the mechanism by which exosomes participate in MAFLD still remain unclear. AIM: To figure out the function of lipotoxic exosomal miR-1297 in MAFLD. METHODS: MicroRNA sequencing was used to detect differentially expressed miRNAs (DE-miR) in lipotoxic exosomes derived from primary hepatocytes. Bioinformatic tools were applied to analyze the target genes and pathways regulated by the DE-miRs. Quantitative real-time PCR (qPCR) was conducted for the verification of DE-miRs. qPCR, western blot, immunofluorescence staining and ethynyl-20-deoxyuridine assay were used to evaluate the function of lipotoxic exosomal miR-1297 on hepatic stellate cells (LX2 cells). A luciferase reporter experiment was performed to confirm the relationship of miR-1297 and its target gene PTEN. RESULTS: MicroRNA sequencing revealed that there were 61 exosomal DE-miRs (P < 0.05) with a fold-change > 2 from palmitic acid treated primary hepatocytes compared with the vehicle control group. miR-1297 was the most highly upregulated according to the microRNA sequencing. Bioinformatic tools showed a variety of target genes and pathways regulated by these DE-miRs were related to liver fibrosis. miR-1297 was overexpressed in exosomes derived from lipotoxic hepatocytes by qPCR. Fibrosis promoting genes (α-SMA, PCNA) were altered in LX2 cells after miR-1297 overexpression or miR-1297-rich lipotoxic exosome incubation via qPCR and western blot analysis. Immunofluorescence staining and ethynyl-20-deoxyuridine staining demonstrated that the activation and proliferation of LX2 cells were also promoted after the above treatment. PTEN was found to be the target gene of miR-1297 and knocking down PTEN contributed to the activation and proliferation of LX2 cells via modulating the PI3K/AKT signaling pathway. CONCLUSION: miR-1297 was overexpressed in exosomes derived from lipotoxic hepatocytes. The lipotoxic hepatocyte-derived exosomal miR-1297 could promote the activation and proliferation of hepatic stellate cells through the PTEN/PI3K/AKT signaling pathway, accelerating the progression of MAFLD.

Deoxycholic acid-stimulated macrophage-derived exosomes promote intestinal metaplasia and suppress proliferation in human gastric epithelial cells.

The crosstalk between macrophages and gastric epithelial cells has emerged as a player in chronic inflammation during intestinal metaplasia. However, the role of bile acid on this modulation remains to be studied. We hypothesized that deoxycholic acid-induced macrophages secreted exosomes to mediate intercellular communication and promoted intestinal metaplasia in human gastric epithelial cells (GES-1 cells). Macrophage-derived exosomes (M-Exos) and deoxycholic acid-induced macrophage-derived exosomes (D-Exos) were isolated by ultracentrifugation. EdU staining and CCK-8 assay were utilized to evaluate the effects of exosomes on the proliferation of GES-1 cells. Intestinal metaplasia was assessed by the expression of caudal-related homeobox transcription factor 2 (CDX2) at both mRNA and protein level. MicroRNA sequencing revealed the microRNA (miRNA) expression profiles of M-Exos and D-Exos. The role of a specific miRNA and mRNA was analyzed by using miRNA mimics, miRNA inhibitors and siRNAs. D-Exos promoted the expression of CDX2 and suppressed the proliferation of GES-1 cells, compared to M-Exos. The miRNA profiles and quantitative real-time PCR examination showed D-Exos enriched a higher level of hsa-miR-30a-5p than M-Exos. Overexpressed has-miR-30a-5p increased CDX2 expression and inhibited the proliferation in GES-1 cells via targeted Forkhead Box D1 (FOXD1), a potential regulatory factor in the process of intestinal metaplasia. D-Exos may promote intestinal metaplasia and suppress proliferation of GES-1 cells via hsa-miR-30a-5p targeting FOXD1, which may be involved in the action mechanism of bile acid on gastric mucosa.

MicroRNA-194 inactivates hepatic stellate cells and alleviates liver fibrosis by inhibiting AKT2.

BACKGROUND: Activation of hepatic stellate cells (HSCs) is a pivotal event in the onset and progression of liver fibrosis. Loss of microRNA-194 (miR-194) has been reported in activated HSCs, but the actual role of miR-194 in liver fibrosis remains uncertain. AIM: To explore the role and potential mechanism of miR-194-mediated regulation of liver fibrosis in vitro and in vivo. METHODS: The expression of miR-194 was examined in human fibrotic liver tissues, activated HSCs, and a carbon tetrachloride (CCl4) mouse model by qPCR. The effects of AKT2 regulation by miR-194 on the activation and proliferation of HSCs were assessed in vitro. For in vivo experiments, we reintroduced miR-194 in mice using a miR-194 agomir to investigate the functions of miR-194 in liver fibrosis. RESULTS: MiR-194 expression was notably lacking in activated HSCs from both humans and mice. Overexpression of miR-194 (OV-miR-194) inhibited α-smooth muscle actin (α-SMA) and type I collagen (Col I) expression and suppressed cell proliferation in HSCs by causing cell cycle arrest in G0/G1 phase. AKT2 was predicted to be a target of miR-194. Notably, the effects of miR-194 knockdown in HSCs were almost blocked by AKT2 deletion, indicating that miR-194 plays a role in HSCs via regulation of AKT2. Finally, miR-194 agomir treatment dramatically ameliorated liver fibrosis in CCl4-treated mice. CONCLUSION: We revealed that miR-194 plays a protective role by inhibiting the activation and proliferation of HSCs via AKT2 suppression. Our results further propose miR-194 as a potential therapeutic target for liver fibrosis.

Zinc-α2-glycoprotein 1 attenuates non-alcoholic fatty liver disease by negatively regulating tumour necrosis factor-α.

BACKGROUND: Zinc-α2-glycoprotein 1 (AZGP1) plays important roles in metabolism-related diseases. The underlying molecular mechanisms and therapeutic effects of AZGP1 remain unknown in non-alcoholic fatty liver disease (NAFLD). AIM: To explore the effects and potential mechanism of AZGP1 on NAFLD in vivo and in vitro. METHODS: The expression of AZGP1 and its effects on hepatocytes were examined in NAFLD patients, CCl4-treated mice fed a high fat diet (HFD), and human LO2 cells. RESULTS: AZGP1 levels were significantly decreased in liver tissues of NAFLD patients and mice. AZGP1 knockdown was found to activate inflammation; enhance steatogenesis, including promoting lipogenesis [sterol regulatory element-binding protein (SREBP)-1c, liver X receptor (LXR), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and stearoyl CoA desaturase 1 (SCD)-1], increasing lipid transport and accumulation [fatty acid transport protein (FATP), carnitine palmitoyl transferase (CPT)-1A, and adiponectin], and reducing fatty acid ß-oxidation [farnesoid X receptor (FXR) and peroxisome proliferator-activated receptor (PPAR)-α]; accelerate proliferation; and reverse apoptosis in LO2 cells. AZGP1 overexpression (OV-AZGP1) had the opposite effects. Furthermore, AZGP1 alleviated NAFLD by blocking TNF-α-mediated inflammation and intracellular lipid deposition, promoting proliferation, and inhibiting apoptosis in LO2 cells. Finally, treatment with OV-AZGP1 plasmid dramatically improved liver injury and eliminated liver fat in NAFLD mice. CONCLUSION: AZGP1 attenuates NAFLD with regard to ameliorating inflammation, accelerating lipolysis, promoting proliferation, and reducing apoptosis by negatively regulating TNF-α. AZGP1 is suggested to be a novel promising therapeutic target for NAFLD.

Effects of Appendectomy on the Onset and Course of Ulcerative Colitis in Chinese Patients.

BACKGROUND: Previous epidemiological studies have suggested that appendectomy may be a protective factor against the development of ulcerative colitis (UC). However, the results of these studies were inconsistent, with rare studies in Chinese populations. AIM: This study examined the associations between appendectomy performed before UC diagnosis and the occurrence and clinical course of UC in Chinese patients. METHODS: A case control study was conducted to compare the rate of appendectomy between UC patients and controls matched for age and sex at two Chinese hospitals. Clinical course of UC was compared between UC patients who underwent appendectomies before UC diagnosis and who did not. RESULTS: 402 UC patients and 402 controls were included. The percentage of appendectomy performed before UC diagnosis in UC patients did not differ significantly from controls (2.74% vs 3.98%, P = 0.442). Subgroup analysis on the basis of localization of UC patients did not find significant difference from controls. The extent of disease involvement in UC patients who underwent appendectomy was smaller than patients who did not (P = 0.009). Appendectomy was found to be significantly related to the location of the disease independent of smoking status in multivariate analysis (P < 0.001). Appendectomy did not influence severity of disease and need for immunosuppressive treatment or colectomy. CONCLUSION: We did not find a significant negative association between appendectomy and the UC occurrence in Chinese patients. Appendectomy performed before UC diagnosis may reduce the extent of UC involvement.