Effects of lifestyle and associated diseases on serum CC16 suggest complex interactions among metabolism, heart and lungs.

INTRODUCTION: Clara cell 16-kDa protein (CC16) is an anti-inflammatory, immunomodulatory secreted pulmonary protein with reduced serum concentrations in obesity according to recent data. OBJECTIVE: Studies focused solely on bodyweight, which does not properly reflect obesity-associated implications of the metabolic and reno-cardio-vascular system. The purpose of this study was therefore to examine CC16 in a broad physiological context considering cardio-metabolic comorbidities of primary pulmonary diseases. METHODS: CC16 was quantified in serum samples in a subset of the FoCus (N = 497) and two weight loss intervention cohorts (N = 99) using ELISA. Correlation and general linear regression analyses were applied to assess CC16 effects of lifestyle, gut microbiota, disease occurrence and treatment strategies. Importance and intercorrelation of determinants were validated using random forest algorithms. RESULTS: CC16 A38G gene mutation, smoking and low microbial diversity significantly decreased CC16. Pre-menopausal female displayed lower CC16 compared to post-menopausal female and male participants. Biological age and uricosuric medications increased CC16 (all p < 0.01). Adjusted linear regression revealed CC16 lowering effects of high waist-to-hip ratio (est. -11.19 [-19.4; -2.97], p = 7.99 × 10-3), severe obesity (est. -2.58 [-4.33; -0.82], p = 4.14 × 10-3) and hypertension (est. -4.31 [-7.5; -1.12], p = 8.48 × 10-3). ACEi/ARB medication (p = 2.5 × 10-2) and chronic heart failure (est. 4.69 [1.37; 8.02], p = 5.91 × 10-3) presented increasing effects on CC16. Mild associations of CC16 were observed with blood pressure, HOMA-IR and NT-proBNP, but not manifest hyperlipidemia, type 2 diabetes, diet quality and dietary weight loss intervention. CONCLUSION: A role of metabolic and cardiovascular abnormalities in the regulation of CC16 and its modifiability by behavioral and pharmacological interventions is indicated. Alterations by ACEi/ARB and uricosurics could point towards regulatory axes comprising the renin-angiotensin-aldosterone system and purine metabolism. Findings altogether strengthen the importance of interactions among metabolism, heart and lungs.

High producer variant of lipoprotein lipase may protect from hepatocellular carcinoma in alcohol-associated cirrhosis.

Background & Aims: Progression of alcohol-associated liver disease (ALD) is driven by genetic predisposition. The rs13702 variant in the lipoprotein lipase (LPL) gene is linked to non-alcoholic fatty liver disease. We aimed at clarifying its role in ALD. Methods: Patients with alcohol-associated cirrhosis, with (n = 385) and without hepatocellular carcinoma (HCC) (n = 656), with HCC attributable to viral hepatitis C (n = 280), controls with alcohol abuse without liver damage (n = 366), and healthy controls (n = 277) were genotyped regarding the LPL rs13702 polymorphism. Furthermore, the UK Biobank cohort was analysed. LPL expression was investigated in human liver specimens and in liver cell lines. Results: Frequency of the LPL rs13702 CC genotype was lower in ALD with HCC in comparison to ALD without HCC both in the initial (3.9% vs. 9.3%) and the validation cohort (4.7% vs. 9.5%; p <0.05 each) and compared with patients with viral HCC (11.4%), alcohol misuse without cirrhosis (8.7%), or healthy controls (9.0%). This protective effect (odds ratio [OR] = 0.5) was confirmed in multivariate analysis including age (OR = 1.1/year), male sex (OR = 3.0), diabetes (OR = 1.8), and carriage of the PNPLA3 I148M risk variant (OR = 2.0). In the UK Biobank cohort, the LPL rs13702 C allele was replicated as a risk factor for HCC. Liver expression of LPL mRNA was dependent on LPL rs13702 genotype and significantly higher in patients with ALD cirrhosis compared with controls and alcohol-associated HCC. Although hepatocyte cell lines showed negligible LPL protein expression, hepatic stellate cells and liver sinusoidal endothelial cells expressed LPL. Conclusions: LPL is upregulated in the liver of patients with alcohol-associated cirrhosis. The LPL rs13702 high producer variant confers protection against HCC in ALD, which might help to stratify people for HCC risk. Impact and implications: Hepatocellular carcinoma is a severe complication of liver cirrhosis influenced by genetic predisposition. We found that a genetic variant in the gene encoding lipoprotein lipase reduces the risk for hepatocellular carcinoma in alcohol-associated cirrhosis. This genetic variation may directly affect the liver, because, unlike in healthy adult liver, lipoprotein lipase is produced from liver cells in alcohol-associated cirrhosis.

Dipeptidylpeptidase (DPP)-4 inhibitor therapy increases circulating levels of anti-inflammatory soluble frizzle receptor protein (sFRP)-5 which is decreased in severe COVID-19 disease.

Obesity and type 2 diabetes (T2D) show an increased risk for a severe COVID-19 disease. Treatment with DPP4 inhibitor (DPP4i) results in reduced mortality and better clinical outcome. Here, we aimed to identify potential mechanisms for the observed DPP4i effect in COVID-19. Comparing T2D subjects with and without DPP4i treatment, we identified a significant increase of the anti-inflammatory adipokine sFRP5 in relation to DPP4 inhibition. sFRP5 is a specific antagonist to Wnt5a, a glycopeptide secreted by adipose tissue macrophages acting pro-inflammatory in various diseases. We therefore examined sFRP5 levels in patients hospitalised for severe COVID-19 and found significant lower levels compared to healthy controls. Since sFRP5 might consequently be a molecular link for the beneficial effects of DPP4i in COVID-19, we further aimed to identify the exact source of sFRP5 in adipose tissue on cellular level. We therefore isolated pre-adipocytes, mature adipocytes and macrophages from adipose tissue biopsies and performed western-blotting. Results showed a sFRP5 expression specifically in mature adipocytes of subcutaneous and omental adipose tissue. In summary, our data suggest that DPP4i increase serum levels of anti-inflammatory sFRP5 which might be beneficial in COVID-19, reflecting a state of sFRP5 deficiency.

Microbiota-dependent activation of the myeloid calcineurin-NFAT pathway inhibits B7H3- and B7H4-dependent anti-tumor immunity in colorectal cancer.

Bacterial sensing by intestinal tumor cells contributes to tumor growth through cell-intrinsic activation of the calcineurin-NFAT axis, but the role of this pathway in other intestinal cells remains unclear. Here, we found that myeloid-specific deletion of calcineurin in mice activated protective CD8+ T cell responses and inhibited colorectal cancer (CRC) growth. Microbial sensing by myeloid cells promoted calcineurin- and NFAT-dependent interleukin 6 (IL-6) release, expression of the co-inhibitory molecules B7H3 and B7H4 by tumor cells, and inhibition of CD8+ T cell-dependent anti-tumor immunity. Accordingly, targeting members of this pathway activated protective CD8+ T cell responses and inhibited primary and metastatic CRC growth. B7H3 and B7H4 were expressed by the majority of human primary CRCs and metastases, which was associated with low numbers of tumor-infiltrating CD8+ T cells and poor survival. Therefore, a microbiota-, calcineurin-, and B7H3/B7H4-dependent pathway controls anti-tumor immunity, revealing additional targets for immune checkpoint inhibition in microsatellite-stable CRC.

Eso-Sponge® for anastomotic leakage after oesophageal resection or perforation: outcomes from a national, prospective multicentre registry.

BACKGROUND: Anastomotic leakage (AL) after oesophagectomy and oesophageal perforations are associated with significant morbidity and mortality. Minimally invasive endoscopy is often used as first-line treatment, particularly endoluminal vacuum therapy (EVT). The aim was to assess the performance of the first commercially available endoluminal vacuum device (Eso-Sponge®) in the management of AL and perforation of the upper gastrointestinal tract (GIT). METHODS: The Eso-Sponge® registry was designed in 2014 as a prospective, observational, national, multicentre registry. Patients were recruited with either AL or perforation within the upper GIT. Data were collected with a standardized form and transferred into a web-based platform. Twenty hospitals were enrolled at the beginning of the study (registration number NCT02662777; http://www.clinicaltrials.gov). The primary endpoint was successful closure of the oesophageal defect. RESULTS: Eleven out of 20 centres recruited patients. A total of 102 patients were included in this interim analysis; 69 patients with AL and 33 with a perforation were treated by EVT. In the AL group, a closure of 91 per cent was observed and 76 per cent was observed in the perforation group. The occurrence of mediastinitis (P = 0.002) and the location of the defect (P = 0.008) were identified as significant predictors of defect closure. CONCLUSIONS: The Eso-Sponge® registry offers the opportunity to collate data on EVT with a uniform, commercially available product to improve standardization. Our data show that EVT with the Eso-Sponge® is an option for the management of AL and perforation within the upper GIT.

A novel unconventional T cell population enriched in Crohn's disease.

OBJECTIVE: One of the current hypotheses to explain the proinflammatory immune response in IBD is a dysregulated T cell reaction to yet unknown intestinal antigens. As such, it may be possible to identify disease-associated T cell clonotypes by analysing the peripheral and intestinal T-cell receptor (TCR) repertoire of patients with IBD and controls. DESIGN: We performed bulk TCR repertoire profiling of both the TCR alpha and beta chains using high-throughput sequencing in peripheral blood samples of a total of 244 patients with IBD and healthy controls as well as from matched blood and intestinal tissue of 59 patients with IBD and disease controls. We further characterised specific T cell clonotypes via single-cell RNAseq. RESULTS: We identified a group of clonotypes, characterised by semi-invariant TCR alpha chains, to be significantly enriched in the blood of patients with Crohn's disease (CD) and particularly expanded in the CD8+ T cell population. Single-cell RNAseq data showed an innate-like phenotype of these cells, with a comparable gene expression to unconventional T cells such as mucosal associated invariant T and natural killer T (NKT) cells, but with distinct TCRs. CONCLUSIONS: We identified and characterised a subpopulation of unconventional Crohn-associated invariant T (CAIT) cells. Multiple evidence suggests these cells to be part of the NKT type II population. The potential implications of this population for CD or a subset thereof remain to be elucidated, and the immunophenotype and antigen reactivity of CAIT cells need further investigations in future studies.

Circulating sDPP-4 is Increased in Obesity and Insulin Resistance but Is Not Related to Systemic Metabolic Inflammation.

CONTEXT: Dipeptidylpeptidase (DPP)-4 is a key regulator of the incretin system. It exists in a membrane-bound form and a soluble form (sDPP-4). Initial human studies suggested sDPP-4 to be an adipokine involved in metabolic inflammation. However, recent mechanistic data in genetically modified mice has questioned these findings. OBJECTIVES: We examined circulating sDPP-4 in a cohort of n = 451 humans with different metabolic phenotypes and during 3 different weight loss interventions (n = 101) to further clarify its role in human physiology and metabolic diseases. DESIGN: sDPP-4 serum concentrations were measured by enzyme-linked immunosorbent assay and related to several phenotyping data including gut microbiome analysis. RESULTS: sDPP-4 increased with age and body weight and was positively associated with insulin resistance and hypertriglyceridemia but was reduced in manifest type 2 diabetes. In addition, we found reduced serum concentrations of sDPP-4 in subjects with arterial hypertension. In contrast to earlier reports, we did not identify an association with systemic markers of inflammation. Impaired kidney and liver functions significantly altered sDPP-4 concentrations while no relation to biomarkers for heart failure was observed. Having found increased levels of sDPP-4 in obesity, we studied surgical (gastric bypass and sleeve gastrectomy) and nonsurgical interventions, revealing a significant association of sDPP-4 with improvement of liver function tests but not with changes in body weight. CONCLUSIONS: Our data suggest that sDPP-4 is related to hepatic abnormalities in obesity rather than primarily functioning as an adipokine and that sDPP-4 is implicated both in glucose and in lipid metabolism, but not fundamentally in systemic inflammation.

Loss of hepatic Mboat7 leads to liver fibrosis.

OBJECTIVE: The rs641738C>T variant located near the membrane-bound O-acyltransferase domain containing 7 (MBOAT7) locus is associated with fibrosis in liver diseases, including non-alcoholic fatty liver disease (NAFLD), alcohol-related liver disease, hepatitis B and C. We aim to understand the mechanism by which the rs641738C>T variant contributes to pathogenesis of NAFLD. DESIGN: Mice with hepatocyte-specific deletion of MBOAT7 (Mboat7Δhep) were generated and livers were characterised by histology, flow cytometry, qPCR, RNA sequencing and lipidomics. We analysed the association of rs641738C>T genotype with liver inflammation and fibrosis in 846 NAFLD patients and obtained genotype-specific liver lipidomes from 280 human biopsies. RESULTS: Allelic imbalance analysis of heterozygous human liver samples pointed to lower expression of the MBOAT7 transcript on the rs641738C>T haplotype. Mboat7Δhep mice showed spontaneous steatosis characterised by increased hepatic cholesterol ester content after 10 weeks. After 6 weeks on a high fat, methionine-low, choline-deficient diet, mice developed increased hepatic fibrosis as measured by picrosirius staining (p<0.05), hydroxyproline content (p<0.05) and transcriptomics, while the inflammatory cell populations and inflammatory mediators were minimally affected. In a human biopsied NAFLD cohort, MBOAT7 rs641738C>T was associated with fibrosis (p=0.004) independent of the presence of histological inflammation. Liver lipidomes of Mboat7Δhep mice and human rs641738TT carriers with fibrosis showed increased total lysophosphatidylinositol levels. The altered lysophosphatidylinositol and phosphatidylinositol subspecies in MBOAT7Δhep livers and human rs641738TT carriers were similar. CONCLUSION: Mboat7 deficiency in mice and human points to an inflammation-independent pathway of liver fibrosis that may be mediated by lipid signalling and a potentially targetable treatment option in NAFLD.

Robotic Roux-en-Y Gastric Bypass Procedure Guide.

PURPOSE: This is a step-by-step procedural guide to help new and unexperienced surgeons with the implementation of a robotic program for the surgical treatment of morbid obesity. METHODS: Based on our vast robotic experience, we present our standardized technique and also, with a PubMed research, discuss the different surgical aspects. RESULTS: We present our trainings pathway towards the first robotic Roux-en-Y gastric bypass, a step-by-step procedural guide with helpful hints when it comes to troubleshooting and also discuss some surgical aspects. CONCLUSION: The robotic Roux-en-Y gastric bypass is safe and feasible, and might offer some advantages in comparison to the laparoscopic approach.

Pros and Cons of Robotic Revisional Bariatric Surgery.

INTRODUCTION: Revisional procedures in bariatric surgery are regarded as technically more demanding and riskier than primary interventions. While the use of the surgical robot has not yet proven to be advantageous in primary bariatric interventions, the question remains whether its use is justified for more complex revisional procedures. OBJECTIVE: To show that revisional bariatric surgery can be performed safely using the da Vinci® Xi surgical system. METHODS: We performed a retrospective analysis of prospectively recorded data for revisional bariatric procedures between January 2016 and November 2019. RESULTS: Of 78 revision operations, four (5.1%) were performed by open surgery, 30 (38.5%) by laparoscopic surgery, and 44 (56.4%) by robotic surgery. A comparative analysis of robotic (n = 41) versus laparoscopic (n = 18) revisional Roux-en-Y gastric bypasses (rRYGB) revealed significant differences favoring the robotic approach for operative time (130.7 vs. 167.6 min), C-reactive protein values at days 1 (27.9 vs. 49.1 mg/L) and 2 (48.2 vs. 83.6 mg/L) after surgery, and length of stay (4.9 vs. 6.2 days). Lower complication rates (Clavien-Dindo II-V) were found after rRRYGB (7.3 vs. 22.2%, not significant). CONCLUSIONS: Revisional bariatric surgery using a robotic system is safe. The operative time performing rRRYGB is significantly shorter than rLRYGB in our experience. Otherwise, results were largely comparable. Due to different indications, different index operations and a wide range of revisional procedures, further studies are necessary to confirm these results.

The Impact of Robotics in Learning Roux-en-Y Gastric Bypass: a Retrospective Analysis of 214 Laparoscopic and Robotic Procedures : Robotic Vs. Laparoscopic RYGB.

BACKGROUND: Proximal Roux-en-Y gastric bypass is commonly used to manage obesity, performed using laparoscopic or robot-assisted minimally invasive surgery. As the prevalence of robotic bariatric surgery increases, further data is required to justify its use. METHODS: This was a large, retrospective analysis of prospectively recorded data for Roux-en-Y gastric bypass (RYGB) procedures performed using laparoscopic (LRYGB) or robotic (RRYGB; da Vinci Xi system, Intuitive Surgical Sàrl) surgery between January 2016 and March 2019. The surgical techniques did not differ apart from different trocar placements. Data collected included patient characteristics before and after RYGB, operative outcomes and complications. RESULTS: In total, 114 RRYGB and 108 LRYGB primary surgeries were performed. There were no significant differences between the groups, apart from a significantly shorter duration of surgery (116.9 vs. 128.9 min, respectively), lower C-reactive protein values at days 1 (31.1 vs. 44.1 mg/l) and 2 (50.3 vs. 77.8 mg/l) after the intervention, and overall complication rate (4.4 vs. 12.0%, Clavien-Dindo classification II-V) with RRYGB compared with LRYGB. There was a lower hemoglobin value in the postoperative course after RRYGB (12.1 vs. 12.6 g/dl, day 2). CONCLUSIONS: In our experience, robotic RYGB has proven to be safe and efficient, with a shorter duration of surgery and lower rate of complications than laparoscopic RYGB. RRYGB is easier to learn and seems safer in less experienced centers. Increasing experience with the robotic system can reduce the duration of surgery over time. Further studies with higher evidence level are necessary to confirm our results.

Shotgun lipidomics-based characterization of the landscape of lipid metabolism in colorectal cancer.

Solid tumors are characterized by global metabolic alterations which contribute to their growth and progression. Altered gene expression profiles and plasma lipid composition suggested a role for metabolic reprogramming in colorectal cancer (CRC) development. However, a conclusive picture of CRC-associated lipidome alterations in the tumor tissue has not emerged. Here, we determined molar abundances of 342 species from 20 lipid classes in matched biopsies of CRC and adjacent normal mucosa. We demonstrate that in contrast to previous reports, CRC shows a largely preserved lipidome composition that resembles that of normal colonic mucosa. Important exceptions include increased levels of lyso-phosphatidylinositols in CRC and reduced abundance of ether phospholipids in advanced stages of CRC. As such, our observations challenge the concept of widespread alterations in lipid metabolism in CRC and rather suggest changes in the cellular lipid profile that are limited to selected lipids involved in signaling and the scavenging of reactive oxygen species.

Use of barbed sutures in robotic bariatric bypass surgery: a single-center case series.

BACKGROUND: Surgical robots are increasingly being used in bariatric surgery. While several studies describe the safety of using barbed sutures in laparoscopic gastric bypass surgery, no reports are available for robotic bariatric procedures. The aim of our article is to determine whether barbed sutures can be used safely in robotic Roux-en-Y bypass (RYGB) surgery. METHODS: This was a single-center, single-surgeon case series of RYGB procedures using the da Vinci® Xi Surgical System (Intuitive Surgery, Sunnyvale, CA, USA) in combination with the use of barbed sutures (Stratafix, Ethicon, Johnson & Johnson, Cincinnati, OH, USA). RESULTS: Fifty robotic proximal and distal RYGB surgeries were performed. A linear stapled, side-to-side gastrojejunostomy was carried out, whereby the enterotomy was completed with a running resorbable unidirectional barbed suture, Stratafix 2-0. In one case after robotic proximal RYGB, revision surgery was required due to omentum necrosis. Another patient was readmitted due to gastrointestinal bleeding from anastomosis. No anastomotic insufficiencies, no stenoses, or higher-grade complications according to Clavien-Dindo 4a-5 were found. CONCLUSIONS: We found that the use of self-fixing barbed sutures in robotic RYGB is safe. The self-fixing suture enables the robotic surgeon to perform a simple continuous suture without the need for recurrent retraction. Although we are the first to report this procedure, we had a low number of cases and no control group; thus, further studies with a higher level of evidence are required.

Variants in ABCG8 and TRAF3 genes confer risk for gallstone disease in admixed Latinos with Mapuche Native American ancestry.

Latin Americans and Chilean Amerindians have the highest prevalence of gallstone disease (GSD) and gallbladder cancer (GBC) in the world. A handful of loci have been associated with GSD in populations of predominantly European ancestry, however, they only explain a small portion of the genetic component of the disease. Here, we performed a genome-wide association study (GWAS) for GSD in 1,095 admixed Chilean Latinos with Mapuche Native American ancestry. Disease status was assessed by cholecystectomy or abdominal ultrasonography. Top-10 candidate variants surpassing the suggestive cutoff of P < 1 × 10-5 in the discovery cohort were genotyped in an independent replication sample composed of 1,643 individuals. Variants with positive replication were further examined in two European GSD populations and a Chilean GBC cohort. We consistently replicated the association of ABCG8 gene with GSD (rs11887534, P = 3.24 × 10-8, OR = 1.74) and identified TRAF3 (rs12882491, P = 1.11 × 10-7, OR = 1.40) as a novel candidate gene for the disease in admixed Chilean Latinos. ABCG8 and TRAF3 variants also conferred risk to GBC. Gene expression analyses indicated that TRAF3 was significantly decreased in gallbladder (P = 0.015) and duodenal mucosa (P = 0.001) of GSD individuals compared to healthy controls, where according to GTEx data in the small intestine, the presence of the risk allele contributes to the observed effect. We conclude that ABCG8 and TRAF3 genes are associated with GSD and GBC in admixed Latinos and that decreased TRAF3 levels could enhance gallbladder inflammation as is observed in GSD and GSD-associated GBC.

Genome-wide association analysis of diverticular disease points towards neuromuscular, connective tissue and epithelial pathomechanisms.

OBJECTIVE: Diverticular disease is a common complex disorder characterised by mucosal outpouchings of the colonic wall that manifests through complications such as diverticulitis, perforation and bleeding. We report the to date largest genome-wide association study (GWAS) to identify genetic risk factors for diverticular disease. DESIGN: Discovery GWAS analysis was performed on UK Biobank imputed genotypes using 31 964 cases and 419 135 controls of European descent. Associations were replicated in a European sample of 3893 cases and 2829 diverticula-free controls and evaluated for risk contribution to diverticulitis and uncomplicated diverticulosis. Transcripts at top 20 replicating loci were analysed by real-time quatitative PCR in preparations of the mucosal, submucosal and muscular layer of colon. The localisation of expressed protein at selected loci was investigated by immunohistochemistry. RESULTS: We discovered 48 risk loci, of which 12 are novel, with genome-wide significance and consistent OR in the replication sample. Nominal replication (p<0.05) was observed for 27 loci, and additional 8 in meta-analysis with a population-based cohort. The most significant novel risk variant rs9960286 is located near CTAGE1 with a p value of 2.3×10-10 and 0.002 (ORallelic=1.14 (95% CI 1.05 to 1.24)) in the replication analysis. Four loci showed stronger effects for diverticulitis, PHGR1 (OR 1.32, 95% CI 1.12 to 1.56), FAM155A-2 (OR 1.21, 95% CI 1.04 to 1.42), CALCB (OR 1.17, 95% CI 1.03 to 1.33) and S100A10 (OR 1.17, 95% CI 1.03 to 1.33). CONCLUSION: In silico analyses point to diverticulosis primarily as a disorder of intestinal neuromuscular function and of impaired connective fibre support, while an additional diverticulitis risk might be conferred by epithelial dysfunction.

Heterozygous carriage of the alpha1-antitrypsin Pi*Z variant increases the risk to develop liver cirrhosis.

OBJECTIVE: Homozygous alpha1-antitrypsin (AAT) deficiency increases the risk for developing cirrhosis, whereas the relevance of heterozygous carriage remains unclear. Hence, we evaluated the impact of the two most relevant AAT variants ('Pi*Z' and 'Pi*S'), present in up to 10% of Caucasians, on subjects with non-alcoholic fatty liver disease (NAFLD) or alcohol misuse. DESIGN: We analysed multicentric case-control cohorts consisting of 1184 people with biopsy-proven NAFLD and of 2462 people with chronic alcohol misuse, both cohorts comprising cases with cirrhosis and controls without cirrhosis. Genotyping for the Pi*Z and Pi*S variants was performed. RESULTS: The Pi*Z variant presented in 13.8% of patients with cirrhotic NAFLD but only in 2.4% of counterparts without liver fibrosis (p<0.0001). Accordingly, the Pi*Z variant increased the risk of NAFLD subjects to develop cirrhosis (adjusted OR=7.3 (95% CI 2.2 to 24.8)). Likewise, the Pi*Z variant presented in 6.2% of alcohol misusers with cirrhosis but only in 2.2% of alcohol misusers without significant liver injury (p<0.0001). Correspondingly, alcohol misusers carrying the Pi*Z variant were prone to develop cirrhosis (adjusted OR=5.8 (95% CI 2.9 to 11.7)). In contrast, the Pi*S variant was not associated with NAFLD-related cirrhosis and only borderline with alcohol-related cirrhosis (adjusted OR=1.47 (95% CI 0.99 to 2.19)). CONCLUSION: The Pi*Z variant is the hitherto strongest single nucleotide polymorphism-based risk factor for cirrhosis in NAFLD and alcohol misuse, whereas the Pi*S variant confers only a weak risk in alcohol misusers. As 2%-4% of Caucasians are Pi*Z carriers, this finding should be considered in genetic counselling of affected individuals.

Treatment of Complicated Anal Fistula by an Endofistular Polyurethane-Sponge Vacuum Therapy: A Pilot Study.

BACKGROUND: Treatment of supra- and transsphincteric anal fistulas remains a clinical challenge because current treatment results are variable and potentially endanger sphincter function. OBJECTIVE: Based on positive results of endoluminal polyurethane-sponge vacuum therapy in the upper and lower GI tract, a new system for endofistular vacuum therapy was developed for anal fistulas to utilize vacuum therapy to remove the endofistular pseudoepithelium and to induce granulation in the fistula tract. DESIGN: This study is based on a prospective case series. PATIENTS: Seven patients with complicated anal fistulas (3 associated with Crohn's disease and 4 of cryptoglandular origin) longer than 4 cm were treated. Initially, the fistula was curettaged and the first endofistular vacuum therapy sponge was positioned in the fistula tract. The inner fistula opening was closed by suture. A 125 mm Hg constant vacuum was applied to the sponge, and the endofistular vacuum therapy sponge was changed a median of 3 (3-5) times after each 48 to 72 hours of constant vacuum therapy. After final removal, the fistulas were reevaluated every other week for 3 months. MAIN OUTCOME MEASURE: The main outcome measured was the closure of the fistula. RESULTS: All patients tolerated the therapy well and no adverse events were observed. Fistula tract closure was demonstrated within 4 weeks after the termination of vacuum therapy. One patient with cryptoglandular fistula developed a recurrence within the follow-up of 3 months. LIMITATIONS: This was an observational study that had no control arm. CONCLUSION: In this pilot case series, the results are encouraging. Because endoluminal vacuum therapy would be a new and sphincter-sparing therapy, this concept warrants further investigation in controlled trials.

Epigenomic map of human liver reveals principles of zonated morphogenic and metabolic control.

A deeper epigenomic understanding of spatial organization of cells in human tissues is an important challenge. Here we report the first combined positional analysis of transcriptomes and methylomes across three micro-dissected zones (pericentral, intermediate and periportal) of human liver. We identify pronounced anti-correlated transcriptional and methylation gradients including a core of 271 genes controlling zonated metabolic and morphogen networks and observe a prominent porto-central gradient of DNA methylation at binding sites of 46 transcription factors. The gradient includes an epigenetic and transcriptional Wnt signature supporting the concept of a pericentral hepatocyte regeneration pathway under steady-state conditions. While donors with non-alcoholic fatty liver disease show consistent gene expression differences corresponding to the severity of the disease across all zones, the relative zonated gene expression and DNA methylation patterns remain unchanged. Overall our data provide a wealth of new positional insights into zonal networks controlled by epigenetic and transcriptional gradients in human liver.

Histologic improvement of NAFLD in patients with obesity after bariatric surgery based on standardized NAS (NAFLD activity score).

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder in industrialized countries. Nonalcoholic steatohepatitis is the fastest growing cause for liver failure. Bariatric surgery represents a treatment option for NAFLD with an established effect on liver histology. OBJECTIVES: We aimed to assess the impact of bariatric surgery on standardized liver histology using the NAFLD activity score. SETTING: Retrospective comparison of metabolic data before and after bariatric surgery and comparison of sleeve gastrectomy and Roux-en-Y gastric bypass. The study was performed in an academic center, the university hospital Schleswig-Holstein in Kiel, Germany. METHODS: Between 2009 and 2012, bariatric surgery was performed in 257 patients according to the national guidelines, and a liver biopsy was obtained in 150 of these patients during surgery. A follow-up biopsy was available in 53 of these patients at a median of 192 days. Liver histology was analyzed using the NAFLD activity score. In this subgroup of 53 patients an analysis of the metabolic improvement after bariatric surgery and a comparative analysis between the 2 different operative procedures was performed. RESULTS: The study cohort showed improvement of preoperative pathologic liver histology findings after operative procedures took place. Both surgery methods improved the NAFLD activity score significantly, all improvement -2.0 (confidence interval -2.5 to -1.0; P < .001); Roux-en-Y gastric bypass, improvement -1.0 (confidence interval -2.0 to -.0; P = .038); sleeve gastrectomy, improvement -2.5 (confidence interval -3.5 to -1.5; P < .001). No differences were found with regard to histologic recovery between gastric bypass and sleeve gastrectomy (P = .22). CONCLUSIONS: Bariatric surgery significantly improves NAFLD.

Comparison of Gene Expression Patterns Between Mouse Models of Nonalcoholic Fatty Liver Disease and Liver Tissues From Patients.

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder in industrialized countries. Mouse models of NAFLD have been used in studies of pathogenesis and treatment, and have certain features of the human disease. We performed a systematic transcriptome-wide analysis of liver tissues from patients at different stages of NAFLD progression (ranging from healthy obese individuals to those with steatosis), as well as rodent models of NAFLD, to identify those that most closely resemble human disease progression in terms of gene expression patterns. METHODS: We performed a systematic evaluation of genome-wide messenger RNA expression using liver tissues collected from mice fed a standard chow diet (controls) and 9 mouse models of NAFLD: mice on a high-fat diet (with or without fructose), mice on a Western-type diet, mice on a methionine- and choline-deficient diet, mice on a high-fat diet given streptozotocin, and mice with disruption of Pten in hepatocytes. We compared gene expression patterns with those of liver tissues from 25 patients with nonalcoholic steatohepatitis (NASH), 27 patients with NAFLD, 15 healthy obese individuals, and 39 healthy nonobese individuals (controls). Liver samples were obtained from patients undergoing liver biopsy for suspected NAFLD or NASH, or during liver or bariatric surgeries. Data sets were analyzed using the limma R-package. Overlap of functional profiles was analyzed by gene set enrichment analysis profiles. RESULTS: We found differences between human and mouse transcriptomes to be significantly larger than differences between disease stages or models. Of the 65 genes with significantly altered expression in patients with NASH and 177 genes with significantly altered expression in patients with NAFLD, compared with controls, only 1-18 of these genes also differed significantly in expression between mouse models of NAFLD and control mice. However, expression of genes that regulate pathways associated with the development of NAFLD were altered in some mouse models (such as pathways associated with lipid metabolism). On a pathway level, gene expression patterns in livers of mice on the high-fat diet were associated more closely with human fatty liver disease than other models. CONCLUSIONS: In comparing gene expression profiles between liver tissues from different mouse models of NAFLD and patients with different stages of NAFLD, we found very little overlap. Our data set is available for studies of pathways that contribute to the development of NASH and NAFLD and selection of the most applicable mouse models (http://www.nash-profiler.com).