Olfactomedin 4 deletion exacerbates nonalcoholic fatty liver disease through P62-dependent mitophagy in mice

BACKGROUND & AIMS

Olfactomedin 4 (OLFM4) is a glycoprotein that is related to obesity and insulin resistance. This study aims to investigate the role and mechanisms of OLFM4 in nonalcoholic fatty liver disease (NAFLD).

APPROACH & RESULTS

OLFM4 expression levels were significantly increased in liver samples from NAFLD patients and in cellular and mouse models of NAFLD. Cell lines deficient in or overexpressing OLFM4 and Olfm4-/- mice were established to study its role in NAFLD. OLFM4 deficiency significantly aggravated diet-induced hepatic steatosis and inflammation, while re-expression of OLFM4 ameliorated diet-induced hepatic steatosis and inflammation in mice. Mechanistically, OLFM4 deficiency disrupted mitochondrial structure and decreased mitophagy in hepatocytes, thereby aggravating hepatic lipogenesis, inflammation, and insulin resistance. Moreover, OLFM4 directly interacted with P62, and OLFM4 deficiency decreased mitophagy in both cellular and mouse models of NAFLD through a P62-dependent mechanism. We also show that blocking the P62-ZZ-domain using XRK3F2 prevented diet-induced NAFLD in Olfm4-/- mice.

CONCLUSION

OLFM4 is significantly upregulated in NAFLD, and OLFM4 deletion exacerbates NAFLD through P62-dependent mitophagy.

A simpler definition of MAFLD precisely predicts incident metabolic diseases: a 7-year cohort study

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a novel definition proposed in 2020 with a relatively complex set of criteria. Thus, simplified criteria that are more applicable are required. This study aimed to develop a simplified set of criteria for identifying MAFLD and predicting MAFLD-related metabolic diseases.

METHODS

We developed a simplified set of metabolic syndrome-based criteria for MAFLD, and compared the performance of the simplified criteria with that of the original criteria in predicting MAFLD-related metabolic diseases in a 7-year follow-up.

RESULTS

In the 7-year cohort, a total of 13,786 participants, including 3372 (24.5%) with fatty liver, were enrolled at baseline. Of the 3372 participants with fatty liver, 3199 (94.7%) met the MAFLD-original criteria, 2733 (81.0%) met the simplified criteria, and 164 (4.9%) were metabolic healthy and met neither of the criteria. During 13,612 person-years of follow-up, 431 (16.0%) fatty liver individuals newly developed T2DM, with an incidence rate of 31.7 per 1000 person-years. Participants who met the simplified criteria had a higher risk of incident T2DM than those who met the original criteria. Similar results were observed for incident hypertension, and incident carotid atherosclerotic plaque.

CONCLUSION

The MAFLD-simplified criteria are an optimized risk stratification tool for predicting metabolic diseases in fatty liver individuals.

USP25 regulates KEAP1-NRF2 anti-oxidation axis and its inactivation protects acetaminophen-induced liver injury in male mice

Nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor responsible for mounting an anti-oxidation gene expression program to counter oxidative stress. Under unstressed conditions, Kelch-like ECH-associated protein 1 (KEAP1), an adaptor protein for CUL3 E3 ubiquitin ligase, mediates NRF2 ubiquitination and degradation. We show here that the deubiquitinase USP25 directly binds to KEAP1 and prevents KEAP1's own ubiquitination and degradation. In the absence of Usp25 or if the DUB is inhibited, KEAP1 is downregulated and NRF2 is stabilized, allowing the cells to respond to oxidative stress more readily. In acetaminophen (APAP) overdose-induced oxidative liver damage in male mice, the inactivation of Usp25, either genetically or pharmacologically, greatly attenuates liver injury and reduces the mortality rates resulted from lethal doses of APAP.

Celastrol pretreatment attenuates concanavalin A-induced hepatitis in mice by suppressing interleukin-6/STAT3-interleukin-17 signaling

BACKGROUND AND AIM

Celastrol is extracted from Tripterygium wilfordii Hook F. It has been reported to have protective effects against various liver diseases and immune regulation of autoimmune diseases. However, little is known about whether celastrol protects against immune-mediated hepatitis. This study aimed to investigate the effect of celastrol on liver injury induced by concanavalin A (ConA) and the potential mechanisms.

METHODS

Intravenous administration of ConA was applied to induce acute liver injury in mice with or without pretreatment of celastrol. The effects of celastrol on ConA-induced liver injury were further demonstrated by biochemical and histopathological assessments, immunoblotting, and flow cytometry analysis.

RESULTS

Both biochemical and histopathological observations showed that pretreatment of celastrol significantly ameliorated liver injury induced by ConA. Moreover, the hepatocyte apoptosis and inflammatory responses induced by ConA were also improved in celastrol-pretreated mice. Further studies revealed that these improvements were characterized as the celastrol-mediated suppression of total interleukin (IL)-17 from liver mononuclear cells in ConA-treated mice. Flow cytometry analysis suggested that celastrol specifically decreased IL-17 production by CD4⁺ T cells but not by CD8⁺ T cells. Fundamentally, pretreatment with celastrol inhibited both the IL-6 produced by F4/80⁺ macrophages and the IL-6 receptor on Th17 cells in the liver, which further led to the downregulated activation of STAT3, thus accounting for blocked Th17 signaling.

CONCLUSIONS

Celastrol may exhibit immune regulatory effects by regulating IL-6/STAT3-IL-17 signaling in ConA-induced hepatitis, which suggested new potentials for celastrol to be applied in treating immune-mediated liver diseases.

A new protective gel to facilitate ulcer healing in artificial ulcers following oesophageal endoscopic submucosal dissection: a multicentre, randomized trial

There are significant risks of adverse events following oesophageal endoscopic submucosal dissection (ESD), such as stricture, delayed bleeding and perforation. Therefore, it is necessary to protect artificial ulcers and promote the healing process. The current study was performed to investigate the protective role of a novel gel against oesophageal ESD-associated wounds. This was a multicentre, randomized, single-blind, controlled trial that recruited participants who underwent oesophageal ESD in four hospitals in China. Participants were randomly assigned to the control or experimental group in a 1:1 ratio and the gel was used after ESD in the latter. Masking of the study group allocations was only attempted for participants. The participants were instructed to report any adverse events on post-ESD days 1, 14, and 30. Moreover, repeat endoscopy was performed at the 2-week follow-up to confirm wound healing. Among the 92 recruited patients, 81 completed the study. In the experimental group, the healing rates were significantly higher than those in the control group (83.89 ± 9.51% vs. 73.28 ± 17.81%, P = 0.0013). Participants reported no severe adverse events during the follow-up period. In conclusion, this novel gel could safely, effectively, and conveniently accelerate wound healing following oesophageal ESD. Therefore, we recommend applying this gel in daily clinical practice.

Risk Factors Related to Polyp Miss Rate of Short-Term Repeated Colonoscopy

BACKGROUND

Colonoscopy is regarded as the gold standard for colorectal cancer screening and surveillance. However, previous studies have reported large numbers of polyps were missed during routine colonoscopy.

AIMS

To evaluate polyp miss rate in short-term repeated colonoscopy and explore the related risk factors.

METHODS

A total of 3695 patients and 12,412 polyps were included in our studies. We calculated the miss rate for polyps of different sizes, pathologies, morphologies and locations, and patients of different characteristics. Univariate and multivariate logistic regression analyses were performed to evaluate risk factors related to miss rate.

RESULTS

The polyp miss rate was 26.3% and the adenoma miss rate was 22.4% in our study. The advanced adenoma miss rate was 11.0% and the proportion of missed advanced adenomas in missed adenomas sized > 5 mm was up to 22.8%. Polyps sized < 5 mm had a significantly higher miss rate. The miss rate of pedunculated polyps was lower than that of flat or sessile polyps. Polyps in the right colon were prone to be missed than that in the left colon. For older men, current smokers, individuals with multiple polyps detected in the first colonoscopy, the risk of missing polyps was significantly higher.

CONCLUSION

Nearly a quarter of polyps were missed during routine colonoscopy. Diminutive, flat, sessile, and right-side colon polyps were at higher risk of missing. The risk of missing polyps was higher in older men, current smokers, and individuals with multiple polyps detected in the first colonoscopy than their counterparts.

The associations between modifiable risk factors and nonalcoholic fatty liver disease: A comprehensive Mendelian randomization study

BACKGROUND AND AIMS

Early identification of modifiable risk factors is essential for the prevention of nonalcoholic fatty liver disease (NAFLD). We aimed to systematically explore the relationships between genetically predicted modifiable risk factors and NAFLD.

APPROACH AND RESULTS

We applied univariable and multivariable Mendelian randomization analyses to explore the relationships between 35 modifiable risk factors and NAFLD. We also evaluated the combined results in three independent large genome-wide association studies. Genetically predicted alcohol frequency, elevated serum levels of liver enzymes, triglycerides, C-reactive protein, and obesity traits, including body mass index, waist circumference, and body fat mass, were associated with increased risks of NAFLD (all with p  < 0.05). Poor physical condition had a suggestive increased risk for NAFLD (odds ratio [OR] = 2.63, p  = 0.042). Genetically instrumented type 2 diabetes (T2DM), hypothyroidism, and hypertension all increased the risk for NAFLD, and the ORs (95% confidence interval) were 1.508 (1.20-1.90), 13.08 (1.53-111.65), and 3.11 (1.33-7.31) for a 1-U increase in log-transformed odds, respectively. The positive associations of T2DM and hypertension with NAFLD remained significant in multivariable analyses. The combined results from the discovery and two replication datasets further confirmed that alcohol frequency, elevated serum liver enzymes, poor physical condition, obesity traits, T2DM, and hypertension significantly increase the risk of NAFLD, whereas higher education and high-density lipoprotein cholesterol (HDL-cholesterol) could lower NAFLD risk.

CONCLUSIONS

Genetically predicted alcohol frequency, elevated serum liver enzymes, poor physical condition, obesity traits, T2DM, and hypertension were associated with an increased risk of NAFLD, whereas higher education and HDL-cholesterol were associated with a decreased risk of NAFLD.

LECT2 modulates dendritic cell function after Helicobacter pylori infection via the CD209a receptor

BACKGROUND

Helicobacter pylori, a gram-negative bacterium persisting on the gastric mucosa, is involved in the pathogenesis of a variety of gastric diseases. Leukocyte cell-derived chemotaxin 2 (LECT2) treatment increased the phagocytic capacity of lymphocytes and improved immune function in bacterial infection. Whether the immune cells infected with H. pylori are affected by LECT2 is unclear.

METHODS

Bone marrow-derived dendritic cells (BMDCs) from wild-type C57BL/6 mice, CD209a knockout mice, or LECT2 knockout mice were exposed to H. pylori at a multiplicity of infection of 10 for 24 h. The maturity of DCs and the cytokines secreted by DCs were analyzed by flow cytometry, western blot, and real-time PCR. The signaling pathway underlying CD209a activation after LECT2 treatment were also detected.

RESULTS

LECT2 treatment promoted H. pylori-induced BMDC maturation and produced a high level of anti-inflammatory cytokine (IL-10) but a low level of pro-inflammatory cytokine (IL-23p40). Moreover, LECT2-pretreated DCs shifted the development of pro-inflammatory Th1/Th17 cells to Treg cells. CD209a mediated LECT2-induced maturation and secretion of DC in H. pylori-primed BMDCs. LECT2 was further confirmed to induce the secretion of certain cytokines via CD209a-JNK/P38 MAPK pathway.

CONCLUSION

This study reveals that LECT2 modulated the functions of H. pylori-primed DCs in a CD209a-dependent manner, which might hinder the clearance of H. pylori and contribute to its colonization.

The potential bidirectional association between Helicobacter pylori infection and gallstone disease in adults: A two-cohort study

BACKGROUND

Previous studies have suggested that Helicobacter pylori (H. pylori) may act as a precipitating factor in gallstone formation, and the potential association between H. pylori infection and gallstone disease (GD) is still unclear and controversial. This study aimed to clarify the potential bidirectional relationship between H. pylori infection and GD.

METHODS

This retrospective cohort study was performed in a population that underwent health checkups at the hospital between 2013 and 2018. H. pylori infection status was evaluated by urea breath test (UBT), and GD was diagnosed via ultrasound. Cox regression and propensity score matching (PSM) were used.

RESULTS

Among 1011 participants without H. pylori infection at baseline, 134 participants were infected with H. pylori. Among 1192 participants without gallstones or cholecystectomy at baseline, 60 participants developed gallstones or cholecystectomy. The hazard ratio (HR) (95% CI) for incident H. pylori infection comparing the GD versus the no GD group was 1.84 (1.19, 2.85). The age- and sex-adjusted HR (95% CI) for incident GD comparing H. pylori-positive subjects to H. pylori-negative subjects was 1.74 (1.01, 2.98). Consistent results were also found with PSM and multivariate analysis.

CONCLUSIONS

This cohort study demonstrated a potential bidirectional association between H. pylori infection and GD, which provides a basis for indicating the risk of GD and implementing the clinical strategies for GD. For the prevention and treatment of GD, H. pylori infection should be carefully considered and evaluated.

Biglycan promotes hepatic fibrosis through activating heat shock protein 47

BACKGROUND

Biglycan (BGN) is a small leucine-rich proteoglycan that participates in the production of excess extracellular matrix (ECM) and is related to fibrosis in many organs. However, the role of BGN in liver fibrosis remains poorly understood. This study aimed to investigate the role and mechanism of BGN in liver fibrosis.

METHODS

Human liver samples, Bgn^-/0 (BGN KO) mice and a human LX-2 hepatic stellate cells (HSCs) model were applied for the study of experimental fibrosis. GEO data and single-cell RNA-seq data of human liver tissue were analysed as a bioinformatic approach. Coimmunoprecipitation, immunofluorescence staining, western blotting and qRT-PCR were conducted to identify the regulatory effects of BGN on heat shock protein 47 (HSP47) expression and liver fibrosis.

RESULTS

We observed that hepatic BGN expression was significantly increased in patients with fibrosis and in a mouse model of liver fibrosis. Genetic deletion of BGN disrupted TGF-β1 pathway signalling and alleviated liver fibrosis in mice administered carbon tetrachloride (CCl₄ ). siRNA-mediated knockdown of BGN significantly reduced TGF-β1-induced ECM deposition and fibroblastic activation in LX-2 cells. Mechanistically, BGN directly interacted with and positively regulated the collagen synthesis chaperon protein HSP47. Rescue experiments showed that BGN promoted hepatic fibrosis by regulating ECM deposition and HSC activation by positively regulating HSP47.

CONCLUSION

Our data indicate that BGN promotes hepatic fibrosis by regulating ECM deposition and HSC activation through an HSP47-dependent mechanism. BGN may be a new biomarker of hepatic fibrosis and a novel target for disease prevention and treatment.

Causal relationship of sugar-sweetened and sweet beverages with colorectal cancer: a Mendelian randomization study

BACKGROUND AND AIM

Prospective cohort studies have suggested that sugar-sweetened beverages (SSBs) intake is significantly associated with the risk of colorectal cancer (CRC). However, it remains unclear whether this observed association was susceptible to potential confounding factors due to the long-term development process of CRC, and the risk of CRC associated with sweet beverages has rarely been reported. We aimed to investigate the association between SSBs/sweet beverages and CRC risk.

METHODS

We performed two-sample Mendelian randomization (MR) analysis using independent genetic variants for SSBs and sweet beverages from a published genome-wide association study (GWAS). Summary statistics for instrument-outcome associations from two databases for malignant neoplasms of the colon and the rectum (FinnGen and UK Biobank). The inverse weighted method (IVW) meta-analysis was the main method used to estimate the relationship, and sensitivity analyses were performed with Cochran's Q test, leave-one-out analysis, MR-Egger regression, Steiger filtering, and the MR PRESSO test.

RESULTS

Genetically predicted SSBs intake was associated with a higher colonic malignant neoplasms risk (odds ratio (OR): 1.013; 95% confidence interval (CI) 1.001, 1.026; P = 0.036) in a combined sample size of 579,986 individuals (4029 cases). Such a significant causal effect of SSBs on rectal malignant neoplasms or sweet beverages on CRC was not observed.

CONCLUSION

Our findings corroborated a causal association between SSBs and colonic malignant neoplasms risk but did not support such a relationship in the analysis of the rectal malignant neoplasms nor the sweet beverage intake, which might be interpreted with caution and further confirmed.

Prospective study of a new endoscopic duodenal-jejunal bypass sleeve in obese patients with nonalcoholic fatty liver disease (with video)

OBJECTIVES

To evaluate the safety and efficacy of a new endoscopic duodenal-jejunal bypass sleeve (DJBS) in obese patients with nonalcoholic fatty liver disease (NAFLD), while in situ for 3 months, and at 6 months postexplantation.

METHODS

Patients with obesity and NAFLD were enrolled in this single-center, prospective study, wherein the TONGEE DJBS (Tangji Medical, Hangzhou, China) was implanted for 3 months. Primary outcomes were weight loss and changes in hepatic steatosis. Secondary outcomes included changes in liver enzymes, glycemic control, and lipid profile and device safety.

RESULTS

Twenty-six patients (age 35.2 ± 7.2 years; 61.5% women) underwent DJBS implantation. At 3 months, bodyweight change from baseline was -8.0 ± 3.6 kg (P < 0.001), corresponding to 8.9 ± 4.0% of total bodyweight. Hepatic steatosis significantly improved based on controlled attenuation parameter, hepatic steatosis index, and fatty liver index (P < 0.001). Liver enzymes, insulin resistance, and metabolic parameters were also improved. At 6 months postexplantation, weight loss and improvements in hepatic steatosis and liver enzyme levels remained statistically significant. Only one patient had a serious adverse event, namely, upper gastrointestinal hemorrhage.

CONCLUSIONS

Three-month TONGEE DJBS implantation resulted in significant weight loss and improvement in hepatic steatosis, liver enzymes, insulin resistance, and metabolic parameters in obese patients with NAFLD. Randomized controlled trials are required to further elucidate these initial findings.

Application of a WeChat-based mini-app as a patient reminder in Helicobacter pylori eradication: a prospective multi-center randomized controlled study

BACKGROUND

To improve the eradication rate of H. pylori, researchers have investigated the role of WeChat-based mini-app as an electronic reminding system in H. pylori treatment.

METHODS

Subjects from three medical centers were divided into two groups. Patients in the daily mini-app-based notification system group received daily notifications via the WeChat mini-app. Patients in the control group received one-time verbal education on the first clinical visit. Both groups received a 14-day quadruple therapy to eradicate H. pylori infection. Eradication rate, compliance, adverse events and satisfaction were evaluated.

RESULTS

Both intention-to-treat (ITT) and per-protocol (PP) analyses were conducted. The eradication rate in the daily mini-app-based notification system group was slightly higher compared with the control group (ITT analysis: 76.70% vs. 70.73%, p = 0.312; PP analysis: 85.87% vs. 82.86%, p = 0.562). The compliance was significantly higher in the daily mini-app-based notification system group (ITT analysis: 85.52% vs. 70.48%, p = 0.028; PP analysis: 92.39% vs. 81.90%, p = 0.030). The adverse event rates were similar between the two groups (PP analysis: 36.96% vs. 40.95%, p = 0.566). No significant difference in eradication rate was seen in each subgroup analysis by age, place of residence, grade of education, or endoscopic findings.

CONCLUSION

The study showed that daily mini-app-based notification improved patient compliance but not H. pylori eradication rate. Trial registration The research was registered in the Chinese Clinical Trial Registry (ChiCTR2000031011, 21/03/2020).

Iron Status and NAFLD among European Populations: A Bidirectional Two-Sample Mendelian Randomization Study

Background and aim: Previous observational studies have suggested a paradoxical relationship between iron status and the risk of non-alcoholic fatty liver disease (NAFLD). Observed associations in these epidemiological studies fail to show sequential temporality and suffer from problems of confounding. Therefore, we performed a bidirectional two-sample Mendelian randomization (MR) to evaluate the relationship between serum iron status and NAFLD. Methods: The inverse weighted method (IVW) meta-analysis with the fixed-effect model was the main method to estimate the relationship between iron status, including serum ferritin, iron, transferrin saturation (TSAT) and total iron-binding capacity (TIBC), and NAFLD. Weighted median, penalized weighted median, and MR Robust Adjusted Profile Score (MR RAPS) methods were used as additional analyses. Sensitivity analyses were performed with Cochran's Q test, MR-Egger regression, Steiger filtering, and the MR PRESSO test. Results: Iron status, including serum ferritin, iron, and TSAT, was associated with an increased risk of NAFLD (odds ratio (OR) (95% confidence interval (CI)): 1.25 (1.06, 1.48); 1.24 (1.05, 1.46), 1.16 (1.02, 1.31), respectively). In contrast, minimal effects of NAFLD on serum ferritin, iron, TSAT, and TIBC were observed (OR (95% CI): 1.01 (1.00, 1.02), 1.01 (1.00, 1.02), 1.03 (1.01, 1.05), 1.03 (1.01, 1.05), respectively). Conclusions: Our findings corroborated the causal associations between serum ferritin, iron, TSAT, and NAFLD, which might suggest the potential benefits of iron-related therapy. In addition, NAFLD might, in turn, slightly affect iron homeostasis indicated as serum ferritin, iron, TSAT, and TIBC, but this needs to be further confirmed.

Endoscopic mucosal resection-precutting vs conventional endoscopic mucosal resection for sessile colorectal polyps sized 10-20 mm

BACKGROUND

The optimal method to remove sessile colorectal lesions sized 10-20 mm remains uncertain. Piecemeal and incomplete resection are major limitations in current practice, such as endoscopic mucosal resection (EMR) and cold or hot snare polypectomy. Recently, EMR with circumferential precutting (EMR-P) has emerged as an effective technique, but the quality of current evidence in comparative studies of conventional EMR (CEMR) and EMR-P is limited.

AIM

To investigate whether EMR-P is superior to CEMR in removing sessile colorectal polyps.

METHODS

This multicenter randomized controlled trial involved seven medical institutions in China. Patients with colorectal polyps sized 10-20 mm were enrolled and randomly assigned to undergo EMR-P or CEMR. EMR-P was performed following submucosal injection, and a circumferential mucosa incision (precutting) was conducted using a snare tip. Primary outcomes included a comparison of the rates of en bloc and R0 resection, defined as one-piece resection and one-piece resection with histologically assessed clear margins, respectively.

RESULTS

A total of 110 patients in the EMR-P group and 110 patients in the CEMR group were finally evaluated. In the per-protocol analysis, the proportion of en bloc resections was 94.3% [95% confidence interval (CI): 88.2%-97.4%] in the EMR-P group and 86% (95%CI: 78.2%-91.3%) in the CEMR group (P = 0.041), while subgroup analysis showed that for lesions > 15 mm, EMR-P also resulted in a higher en bloc resection rate (92.0% vs 58.8% P = 0.029). The proportion of R0 resections was 81.1% (95%CI: 72.6%-87.4%) in the EMR-P group and 76.6% (95%CI: 68.8%-84.4%) in the CEMR group (P = 0.521). The EMR-P group showed a longer median procedure time (6.4 vs 3.0 min; P < 0.001). No significant difference was found in the proportion of patients with adverse events (EMR-P: 9.1%; CEMR: 6.4%; P = 0.449).

CONCLUSION

In this study, EMR-P served as an alternative to CEMR for removing nonpedunculated colorectal polyps sized 10-20 mm, particularly polyps > 15 mm in diameter, with higher R0 and en bloc resection rates and without increasing adverse events. However, EMR-P required a relatively longer procedure time than CEMR. Considering its potential benefits for en bloc and R0 resection, EMR-P may be a promising technique in colorectal polyp resection.

The Role of Short Chain Fatty Acids in Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder that is characterized by abdominal pain and disordered bowel habits. The etiology of IBS is multifactorial, including abnormal gut-brain interactions, visceral hypersensitivity, altered colon motility, and psychological factors. Recent studies have shown that the intestinal microbiota and its metabolites short chain fatty acids (SCFAs) may be involved in the pathogenesis of IBS. SCFAs play an important role in the pathophysiology of IBS. We discuss the underlying mechanisms of action of SCFAs in intestinal inflammation and immunity, intestinal barrier integrity, motility, and the microbiota-gut-brain axis. Limited to previous studies, further studies are required to investigate the mechanisms of action of SCFAs in IBS and provide more precise therapeutic strategies for IBS.

Minimal water exchange by the air-water valve versus left colon water exchange in unsedated colonoscopy: a randomized controlled trial

BACKGROUND

Water exchange colonoscopy is the least painful method for unsedated colonoscopies. Simplified left colon water exchange (LWE) reduces the cecal intubation time but it is difficult to avoid the use of an additional pump. Minimal water exchange (MWE) is an improved novel method that eliminates the need for pumps, but it is not clear whether MWE has the same efficiency as LWE.

METHODS

This was a prospective, randomized, controlled, noninferiority trial conducted in a tertiary hospital. Enrolled patients were randomized 1:1 to the LWE group or MWE group. The primary outcome was recalled insertion pain measured by a 4-point verbal rating scale. Secondary outcomes included adenoma detection rate (ADR), cecal intubation time, volume of water used, and patient willingness to repeat unsedated colonoscopy.

RESULTS

226 patients were included (LWE n = 113, MWE n = 113). The MWE method showed noninferior moderate/severe pain rates compared with the LWE method (10.6 % vs. 9.7 %), with a difference of 0.9 percentage points (99 % confidence interval [CI] -9.5 to 11.3; threshold, 15 %). ADR, cecal intubation time, and willingness to repeat unsedated colonoscopy were not significantly different between the two groups, but the mean volume of water used was significantly less with MWE than with LWE (163.7 mL vs. 407.2 mL; 99 %CI -298.28 to -188.69).

CONCLUSION

Compared with LWE, MWE demonstrated a noninferior outcome for insertion pain, and comparable cecal intubation time and ADR, but reduced the volume of water used and eliminated the need for a water pump.

MPST deficiency promotes intestinal epithelial cell apoptosis and aggravates inflammatory bowel disease via AKT

Background & aims

Excessive inflammatory responses and oxidative stress are considered the main characteristics of inflammatory bowel disease (IBD). Endogenous hydrogen sulfide (H₂S) has been reported to show anti-inflammatory activity in IBD. The main aim of this study was to explore the role of 3-mercaptopyruvate sulfurtransferase (MPST), a key enzyme that regulates endogenous H₂S biosynthesis, in IBD.

Methods

Colonic MPST expression was evaluated in mice and patients with IBD. Various approaches were used to explore the concrete mechanism underlying MPST regulation of the progression of colitis through in vivo and in vitro models.

Results

MPST expression was markedly decreased in colonic samples from patients with ulcerative colitis (UC) or Crohn's disease (CD) and from mice treated with DSS. MPST deficiency significantly aggravated the symptoms of murine colitis, exacerbated inflammatory responses and apoptosis, and inhibited epithelium stem cell-derived organoid formation in an H₂S-independent manner. Consistently, when HT29 cells were treated with TNF-α, inhibition of MPST significantly increased the expression of proinflammatory cytokines, the amount of ROS and the prevalence of apoptosis, whereas overexpression of MPST markedly improved these effects. RNA-seq analysis showed that MPST might play a role in regulating apoptosis through AKT signaling. Mechanistically, MPST directly interacted with AKT and reduced the phosphorylation of AKT. Additionally, MPST expression was positively correlated with AKT expression in human IBD samples. In addition, overexpression of AKT rescued IEC apoptosis caused by MPST deficiency, while inhibition of AKT significantly aggravated it.

Conclusions

MPST protects the intestines from inflammation most likely by regulating the AKT/apoptosis axis in IECs. Our results may provide a novel therapeutic strategy for the treatment of colitis.

Gut bacteria alleviate smoking-related NASH by degrading gut nicotine

Tobacco smoking is positively correlated with non-alcoholic fatty liver disease (NAFLD)^1-5, but the underlying mechanism for this association is unclear. Here we report that nicotine accumulates in the intestine during tobacco smoking and activates intestinal AMPKα. We identify the gut bacterium Bacteroides xylanisolvens as an effective nicotine degrader. Colonization of B. xylanisolvens reduces intestinal nicotine concentrations in nicotine-exposed mice, and it improves nicotine-exacerbated NAFLD progression. Mechanistically, AMPKα promotes the phosphorylation of sphingomyelin phosphodiesterase 3 (SMPD3), stabilizing the latter and therefore increasing intestinal ceramide formation, which contributes to NAFLD progression to non-alcoholic steatohepatitis (NASH). Our results establish a role for intestinal nicotine accumulation in NAFLD progression and reveal an endogenous bacterium in the human intestine with the ability to metabolize nicotine. These findings suggest a possible route to reduce tobacco smoking-exacerbated NAFLD progression.

Mass cytometry-based peripheral blood analysis as a novel tool for early detection of solid tumours: a multicentre study

OBJECTIVE

Early detection of a tumour remains an unmet medical need, and approaches with high sensitivity and specificity are urgently required. Mass cytometry time-of-flight (CyTOF) is a powerful technique to profile immune cells and could be applied to tumour detection. We attempted to establish diagnostic models for hepatocellular carcinoma (HCC) and pancreatic ductal adenocarcinoma (PDAC).

DESIGN

We performed CyTOF analysis for 2348 participants from 15 centres, including 1131 participants with hepatic diseases, 584 participants with pancreatic diseases and 633 healthy volunteers. Diagnostic models were constructed through random forest algorithm and validated in subgroups.

RESULTS

We determined the disturbance of systemic immunity caused by HCC and PDAC, and calculated a peripheral blood immune score (PBIScore) based on the constructed model. The PBIScore exhibited good performance in detecting HCC and PDAC, with both sensitivity and specificity being around 80% in the validation cohorts. We further established an integrated PBIScore (iPBIScore) by combining PBIScore and alpha-fetoprotein or carbohydrate antigen 19-9. The iPBIScore for HCC had an area under the curve (AUC) of 0.99, 0.97 and 0.96 in training, internal validation and external validation cohorts, respectively. Similarly, the iPBIScore for PDAC showed an AUC of 0.99, 0.98 and 0.97 in the training, internal validation and external validation cohorts, respectively. In early-stage and tumour-marker-negative patients, our iPBIScore-based models also showed an AUC of 0.95-0.96 and 0.81-0.92, respectively.

CONCLUSION

Our study proved that the alterations of peripheral immune cell subsets could assist tumour detection, and provide a ready-to-use detection model for HCC and PDAC.

Profiles of Acetylation Regulation Genes Contribute to Malignant Progression and Have a Clinical Prognostic Impact on Liver Cancer

Background

Several studies have demonstrated that acetylation was involved in the process of liver cancer. This study aimed to establish an effective predictive prognostic model using acetylation regulation genes in liver cancer.

Methods

Two datasets were downloaded from the Cancer Genome Atlas (TCGA) database and International Cancer Genome Consortium (ICGC) database. Differentially expressed acetylation regulation genes were identified in the TCGA-LIHC dataset, and then, Gene Ontology (GO) functional annotation analysis was used to investigate the molecular mechanism. After grouping the patients into clusters based on consensus clustering, we explored the correlation between clusters and clinical characteristics. A risk model was constructed by the least absolute shrinkage and selection operator (LASSO) regression analysis to calculate the risk score. Patients were divided into high-risk and low-risk groups according to the risk score using the acetylation regulation genes. Data downloaded from LIRI-JP were used for external validation. Univariate and multivariate Cox regressions were performed to identify independent risk factors. A prognostic nomogram was constructed according to the TCGA-LIHC dataset. The effect of HDAC11 expression on the proliferation and migration of liver cancer was detected by the CCK-8 method and cell scratch test, respectively.

Results

Eleven of 29 acetylation regulation genes were identified as upregulated differentially expressed genes. Go enrichment analysis showed that they were involved in "protein and histone deacylation and deacetylation." Patients were categorized into two clusters according to the expression of 29 acetylation regulation genes. Compared with cluster 2, cluster 1 correlated with shorter overall survival (OS) and higher expression. Stage, T stage, grade, gender, age, and follow-up state were significantly different between two clusters. Pathways involved in DNA repair were significantly enriched in cluster 1. The risk score was calculated by HDAC1, HDAC2, HDAC4, HDAC11, HAT1, and SIRT6. Patients in the high-risk group had a worse prognosis in both datasets. Risk score was not only an independent prognostic marker but could also predict the clinicopathological features of liver cancer. A nomogram containing risk score, T stage, and M stage was built to predict overall survival. After transfection with HDAC11 overexpression plasmid, the proliferation ability of HepG2 cells increased, while the migration ability had no change.

Conclusions

Our findings suggested that acetylation regulation genes contribute to malignant progression and have a clinical prognostic impact on liver cancer.

The regulation effect of GLUT9/SLC2A9 on intrahepatic uric acid level and metabolic associated fatty liver disease

BACKGROUND

Metabolic associated fatty liver disease (MAFLD) is the most common chronic liver disease worldwide. The important role of urid acid (UA) in MAFLD has been widely investigated. Our previous studies unveiled the elevation of serum UA levels independently predicts an increased risk of incident MAFLD. However, the role of intrahepatic UA in MAFLD has not been investigated yet. Glucose transporter 9 (GLUT9) is a key transporter that mediates the uptake of UA in hepatocytes.

METHODS

In this study, we first explored the clinical association between GLUT9 polymorphism and MAFLD. Blood samples of 247 male Chinese (127 were MAFLD patients) were collected and tested for the blood UA levels and genotype of the single nucleotide polymorphism (SNP) of GLUT9 (rs1014290). Next, Glut9 hepatic-specific knockout mice (Glut9^Hep-ko) were generated to investigate the role of hepatic GLUT9 in MAFLD in male mice.

RESULTS

We found that the GA/AA genotypes (rs1014290) were associated with elevated serum UA levels in MAFLD patients. Meanwhile, we found that Glut9^Hep-ko mice displayed lower intrahepatic UA levels, down-regulated lipogenesis genes expressions, and attenuated MAFLD symptoms after 12 weeks of high-fat diet feeding, compared with Glut9^Fl/Fl littermates. However, Glut9^Hep-ko mice and wild-type littermates showed no significant difference on hepatic fatty acid oxidation or inflammation.

CONCLUSIONS

Our results suggested that GLUT9 polymorphism was significantly associated with MAFLD, and hepatic-specific knockout of Glut9 significantly decreased intrahepatic contents and ameliorated diet-induced MAFLD in mice.

The DEAD-box helicase DDX3x ameliorates non-alcoholic fatty liver disease via mTORC1 signalling pathway

BACKGROUND & AIMS

The DEAD (Asp-Glu-Ala-Asp)-box helicase family member DDX3x has been proven to involve in hepatic lipid disruption during HCV infection. However, the role of DDX3x in non-alcoholic fatty liver disease (NAFLD), in which lipid homeostasis is severely disrupted, remains unclear. Here, we aimed to illustrate the potential role of DDX3x in NAFLD.

METHODS

DDX3x protein levels were evaluated in NAFLD patients and NAFLD models via immunohistochemistry or western blotting. In vivo ubiquitin assay was performed to identify the ubiquitination levels of DDX3x in the progression of steatosis. DDX3x protein levels in mice livers were manipulated by adeno-associated virus-containing DDX3x short hairpin RNA or DDX3x overexpression plasmid. Hepatic or serum triglyceride and total cholesterol were evaluated and hepatic steatosis was confirmed by haematoxylin and eosin staining and oil red o staining. Western blotting was performed to identify the underlying mechanisms of DDX3x involving in the progression of NAFLD.

RESULTS

DDX3x protein levels were significantly decreased in NAFLD patients and NAFLD models. DDX3x protein might be degraded via ubiquitin-proteasome system in the progression of steatosis. Knockdown of hepatic DDX3x exacerbated HFD-induced hepatic steatosis in mice, while overexpression of hepatic DDX3x alleviated HFD-induced hepatic steatosis in mice. Further explorative experiments revealed that knockdown of DDX3x could lead to the overactivation of mTORC1 signalling pathway which exacerbates NAFLD.

CONCLUSIONS

DDX3x involved in the progression of NAFLD via affecting the mTORC1 signalling pathway. DDX3x might be a potential target for NAFLD treatment.

Gestational Diabetes Sensitizes Mice to Future Metabolic Syndrome That Can Be Relieved by Activating CAR

Diabetes and related metabolic syndrome are common metabolic disorders. Gestational diabetes mellitus (GDM) is rather prevalent in the clinic. Although most GDM resolves after therapeutic intervention and/or after delivery, the long-term health effect of GDM remains to be better understood. The constitutive androstane receptor (CAR), initially characterized as a xenobiotic receptor, was more recently proposed to be a therapeutic target for obesity and type 2 diabetes mellitus (T2DM). In this study, high-fat diet (HFD) feeding was used to induce GDM. Upon delivery, GDM mice were returned to chow diet until the metabolic parameters were normalized. Parous non-GDM control females or metabolically normalized GDM females were then subjected to HFD feeding to induce nongestational obesity and T2DM. Our results showed that GDM sensitized mice to metabolic abnormalities induced by a second hit of HFD. Treatment with the CAR agonist 1,4-bis [2-(3,5 dichloropyridyloxy)] benzene efficiently attenuated GDM-sensitized and HFD-induced obesity and T2DM, including decreased body weight, improved insulin sensitivity, inhibition of hyperglycemia and hepatic steatosis, increased oxygen consumption, and decreased adipocyte hypertrophy. In conclusion, our results have established GDM as a key risk factor for the future development of metabolic disease. We also propose that CAR is a therapeutic target for the management of metabolic disease sensitized by GDM.