Sortilin in Biliary Epithelial Cells Promotes Ductular Reaction and Fibrosis during Cholestatic Injury.

Cholestatic injuries are accompanied by ductular reaction, initiated by proliferation and activation of biliary epithelial cells (BECs), leading to fibrosis. Sortilin (encoded by Sort1) facilitates IL-6 secretion and leukemia inhibitory factor (LIF) signaling. This study investigated the interplay between sortilin and IL-6 and LIF in cholestatic injury-induced ductular reaction, morphogenesis of new ducts, and fibrosis. Cholestatic injury was induced by bile duct ligation (BDL) in wild-type and Sort1-/- mice, with or without augmentation of IL-6 or LIF. Mice with BEC sortilin deficiency (hGFAPcre.Sort1fl/fl) and control mice were subjected to BDL and 3,5-diethoxycarbonyl-1,4-dihydrocollidine diet (DDC) induced cholestatic injury. Sort1-/- mice displayed reduced BEC proliferation and expression of BEC-reactive markers. Administration of LIF or IL-6 restored BEC proliferation in Sort1-/- mice, without affecting BEC-reactive or inflammatory markers. Sort1-/- mice also displayed impaired morphogenesis, which was corrected by LIF treatment. Similarly, hGFAPcre.Sort1fl/fl mice exhibited reduced BEC proliferation, but similar reactive and inflammatory marker expression. Serum IL-6 and LIF were comparable, yet liver pSTAT3 was reduced, indicating that sortilin is essential for co-activation of LIF receptor/gp130 signaling in BECs, but not for IL-6 secretion. hGFAPcre.Sortfl/fl mice displayed impaired morphogenesis and diminished fibrosis after BDL and DDC. In conclusion, sortilin-mediated engagement of LIF signaling in BECs promoted ductular reaction and morphogenesis during cholestatic injury. This study indicates that BEC sortilin is pivotal for the development of fibrosis.

CD55-deficiency in Jews of Bukharan descent is caused by the Cromer blood type Dr(a-) variant.

The complement system regulator CD55 was initially found to carry the Cromer blood group system antigens, and its complete loss of function was subsequently revealed to cause a severe monogenic gastrointestinal syndrome characterized by protein-losing enteropathy and susceptibility to venous thrombosis. Here we present homozygosity to the CD55 c.596C>T; p.Ser199Leu variant, which was previously described as the Cromer Dr(a-) genotype, in two Bukharan Jewish CD55-deficiency patients with variable disease severity. We confirm that this missense variant causes aberrant splicing and deletion of 44 bp in exon 5, leading to premature termination and low expression of the CD55 protein. Furthermore, Patient 1 exhibited a mildly abnormal B cell immunophenotyping profile. By population screening we established that this variant is highly prevalent in the Bukharan Jewish population, with a carrier frequency of 1:17, suggesting that many similar patients are un- or mis-diagnosed. The phenotypic variability, ranging from abdominal pain when eating a high-fat diet to the full CD55-deficiency phenotype, is likely related to modifiers affecting the proportion of the variant that is able to escape aberrant splicing. Establishing the diagnosis of CD55-deficiency in a timely manner, even in patients with milder symptoms, may have a critical effect on their management and quality-of-life since treatment with the complement inhibitor eculizumab is highly effective in ameliorating disease manifestations. Awareness of founder mutations within certain populations can further guide genetic testing and prevent a diagnostic odyssey, by placing this CD55 variant high on the differential diagnosis.

Repetitive amiodarone administration causes liver damage via adipose tissue ER stress-dependent lipolysis, leading to hepatotoxic free fatty acid accumulation.

Drug-induced liver injury is an emerging form of acute and chronic liver disease that may manifest as fatty liver. Amiodarone (AMD), a widely used antiarrhythmic drug, can cause hepatic injury and steatosis by a variety of mechanisms, not all completely understood. We hypothesized that repetitive AMD administration may induce hepatic lipotoxicity not only via effects on the liver but also via effects on adipose tissue. Indeed, repetitive AMD administration induced endoplasmic reticulum (ER) stress in both liver and adipose tissue. In adipose tissue, AMD reduced lipogenesis and increased lipolysis. Moreover, AMD treatment induced ER stress and ER stress-dependent lipolysis in 3T3L1 adipocytes in vitro. In the liver, AMD caused increased expression of genes encoding proteins involved in fatty acid (FA) uptake and transfer (Cd36, Fabp1, and Fabp4), and resulted in increased hepatic accumulation of free FAs, but not of triacylglycerols. In line with this, there was increased expression of hepatic de novo FA synthesis genes. However, AMD significantly reduced the expression of the desaturase Scd1 and elongase Elovl6, detected at mRNA and protein levels. Accordingly, the FA profile of hepatic total lipids revealed increased accumulation of palmitate, an SCD1 and ELOVL6 substrate, and reduced levels of palmitoleate and cis-vaccenate, products of the enzymes. In addition, AMD-treated mice displayed increased hepatic apoptosis. The studies show that repetitive AMD induces ER stress and aggravates lipolysis in adipose tissue while inducing a lipotoxic hepatic lipid environment, suggesting that AMD-induced liver damage is due to compound insult to liver and adipose tissue.NEW & NOTEWORTHY AMD chronic administration induces hepatic lipid accumulation by several mechanisms, including induction of hepatic ER stress, impairment of ß-oxidation, and inhibition of triacylglycerol secretion. Our study shows that repetitive AMD treatment induces not only hepatic ER stress but also adipose tissue ER stress and lipolysis and hepatic accumulation of free fatty acids and enrichment of palmitate in the total lipids. Understanding the toxicity mechanisms of AMD would help devise ways to limit liver damage.

Endoscopic trans-oral outlet reduction after bariatric surgery is safe and effective for dumping syndrome.

BACKGROUND: Dumping syndrome (DS) is a common complication of bariatric surgery. Treatments include dietary and behavioral changes, as well as pharmacotherapy and revision surgery. All can be costly or hard to adhere to. In recent years, evidence accumulates in favor of endoscopic trans-oral outlet reduction (TORe) as an effective treatment for DS, targeting the pathophysiology of rapid gastric clearance. The objective of this study is to assess the safety and efficacy of TORe for DS in a single referral center. METHODS: Patients after bariatric surgery suffering DS were followed, and data were retrospectively analyzed. Diagnosis and post-procedural assessment of DS were made clinically using Sigstad score. During the procedure, the anastomotic rim was cauterized. Afterwards, 2 non-interrupted "8-figure" sutures were placed, resulting in imbrication of additional gastric tissue on top of the anastomosis and narrowing to <1 cm at the end of the procedure. Patients were instructed to keep a liquid diet for 14 days and follow-up continued for 6 months. RESULTS: Between 8/2018 and 9/2019 TORe was carried out in 13 patients (M:F = 3:10) with mean age of 45.1 (range 25-56) and BMI of 33.5 (range 28.1-40.3). Average time since recent surgery was 5.5 years (range 1-9). Mean pre-procedure anastomosis diameter was 25.2 mm (range 15-30) and was reduced to a mean of 5.6 mm (range 5-10). Three patients (23%) were admitted overnight due to inability to drink which resolved spontaneously. No major complications were reported. At 6 months, the Sigstad score was significantly reduced (19.4 ± 3.6 vs 5.2 ± 5.5, P < 0.001), and 11/13 (85%) of patients had a complete resolution of their dumping symptoms. In addition, BMI decreased by a mean of 2.3 kg/m2 (-1 to 7.5, p = 0.002). CONCLUSION: TORe is a safe and effective treatment for patients suffering dumping syndrome and should be considered early in the treatment of DS.

Efficacy and safety of biosimilar CT-P13 compared with originator infliximab in patients with active Crohn's disease: an international, randomised, double-blind, phase 3 non-inferiority study.

BACKGROUND: The infliximab biosimilar CT-P13 was approved for use in Crohn's disease after clinical comparison with originator infliximab in ankylosing spondylitis and rheumatoid arthritis; however, concerns about such indication extrapolation have been expressed. This study investigated whether CT-P13 is non-inferior to infliximab in patients with Crohn's disease who were naive to biological therapy. METHODS: In this randomised, multicentre, double-blind, phase 3 non-inferiority study, we enrolled patients with active Crohn's disease who had not responded to, or were intolerant to, non-biological treatments. Patients were randomly assigned (1:1:1:1) to receive CT-P13 then CT-P13, CT-P13 then infliximab, infliximab then infliximab, or infliximab then CT-P13, with switching occurring at week 30. Patients received 5 mg/kg CT-P13 or infliximab at weeks 0, 2, 6, and then every 8 weeks up to week 54. The primary endpoint was the proportion of patients with a decrease of 70 points or more in Crohn's Disease Activity Index (CDAI) from baseline to week 6. A non-inferiority margin of -20% was set (CT-P13 was non-inferior to infliximab if the lower limit of the two-sided 95% CI for the treatment difference was greater than -20). This trial is registered with ClinicalTrials.gov, number NCT02096861, and is completed. FINDINGS: Between Aug 20, 2014, and Feb 15, 2017, 308 patients were assessed for eligibility, and 220 patients were enrolled: 111 were randomly assigned to initiate CT-P13 (56 to the CT-P13-CT-P13 group and 55 to the CT-P13-infliximab group) and 109 to initiate infliximab (54 to the infliximab-infliximab group and 55 to the infliximab-CT-P13 group). CDAI-70 response rates at week 6 were similar for CT-P13 (77 [69·4%, 95% CI 59·9 to 77·8] of 111) and infliximab (81 [74·3%, 95% CI 65·1 to 82·2] of 109; difference -4·9% [95% CI -16·9 to 7·3]), thereby establishing non-inferiority. Over the total study period, 147 (67%) patients experienced at least one treatment-emergent adverse event (36 [64%] in the CT-P13-CT-P13 group, 34 [62%] in the CT-P13-infliximab group, 37 [69%] in the infliximab-infliximab group, and 40 [73%] in the infliximab-CT-P13 group). INTERPRETATION: This study showed non-inferiority of CT-P13 to infliximab in patients with active Crohn's disease. Biosimilar CT-P13 could be a new option for the treatment of active Crohn's disease. FUNDING: Celltrion, Pfizer.

Endoscopic treatment of early leaks and strictures after laparoscopic one anastomosis gastric bypass.

BACKGROUND: Laparoscopic one anastomosis gastric bypass has become a prominent bariatric procedure. Yet, early and late complications, primarily leaks and strictures, are not uncommon. This study summarizes our experience with endoscopic treatment of laparoscopic one anastomosis gastric bypass complications. METHODS: This is a retrospective study of consecutive patients referred to our hospital from 2015 to 2017 with post laparoscopic one anastomosis gastric bypass complications. Therapy was tailored to each case, including fully covered self-expandable metal stents, fibrin glue, septotomy, internal drainage with pigtail stents, through-the-scope and pneumatic dilation. Success was defined as resuming oral nutrition without enteral or parenteral support or further surgical intervention. RESULTS: Nine patients presented with acute or early leaks: 5 (56%) had staple-line leaks, 3 (33%) had anastomotic leaks and 1 (11%) had both. All were treated with stents. Adjunctive endoscopic drainage was applied in 4 patients (44%). Overall 5 patients (56%) with acute/ early leaks recovered completely, including all 3 patients with anastomotic leak and the patient with both leaks but only 1/5 with staple line leak (20%). Complication rate in the leak group reached 22%. Eight patients presented with strictures, 7 at the anastomosis and one due to remnant stomach misalignment. All anastomotic strictures were dilated successfully. However, the patient with the pouch stricture required conversion to Roux-en-Y gastric bypass after 3 failed attempts of dilation. CONCLUSION: Endoscopic treatments of laparoscopic one anastomosis gastric bypass complications are relatively effective and safe. Anastomosis-related complications are more amenable to endoscopic treatment compared to staple line leaks.

Glucose-Dependent Insulinotropic Polypeptide Receptor Deficiency Leads to Impaired Bone Marrow Hematopoiesis.

The bone marrow (BM) contains controlled specialized microenvironments, or niches, that regulate the quiescence, proliferation, and differentiation of hematopoietic stem and progenitor cells (HSPC). The glucose-dependent insulinotropic polypeptide (GIP) is a gut-derived incretin hormone that mediates postprandial insulin secretion and has anabolic effects on adipose tissue. Previous studies demonstrated altered bone microarchitecture in mice deficient for GIP receptor (Gipr-/- ), as well as the expression of high-affinity GIP receptor by distinct cells constructing the BM HSPC niche. Nevertheless, the involvement of GIP in the process of BM hematopoiesis remains elusive. In this article, we show significantly reduced representation and proliferation of HSPC and myeloid progenitors in the BM of Gipr-/- mice. This was further manifested by reduced levels of BM and circulating differentiated immune cells in young and old adult mice. Moreover, GIP signaling was required for the establishment of supportive BM HSPC niches during HSPC repopulation in radioablated BM chimera mice. Finally, molecular profiling of various factors involved in retention, survival, and expansion of HSPC revealed significantly lower expression of the Notch-receptor ligands Jagged 1 and Jagged 2 in osteoblast-enriched bone extracts from Gipr-/- mice, which are important for HSPC expansion. In addition, there was increased expression of CXCL12, a factor important for HSPC retention and quiescence, in whole-BM extracts from Gipr-/- mice. Collectively, our data suggest that the metabolic hormone GIP plays an important role in BM hematopoiesis.

Sortilin Deficiency Reduces Ductular Reaction, Hepatocyte Apoptosis, and Liver Fibrosis in Cholestatic-Induced Liver Injury.

Sortilin, a member of the vacuolar protein sorting 10 domain receptor family, traffics newly synthesized proteins from the trans-Golgi network to secretory pathways, endosomes, and cell surface. Sortilin-trafficked molecules, including IL-6 and acid sphingomyelinase (aSMase), mediate cholangiocyte proliferation and liver inflammation, hepatic stellate cell activation, hepatocyte apoptosis, and fibrosis. Based on these sortilin-regulated functions, we investigated its role in biliary damage leading to hepatocellular injury and fibrosis. Sortilin-/- mice displayed impaired inflammation and ductular reaction 3 days after bile duct ligation (BDL), as demonstrated by reduced cholangiocyte proliferation and activation and reduced serum IL-6. Interestingly, liver fibrosis was reduced in Sortilin-/- mice after both BDL and carbon tetrachloride treatment, in line with attenuated in vitro activation of Sortilin-/- hepatic stellate cells. Sortilin-/- hepatic aSMase activity was reduced in the BDL and carbon tetrachloride models and accompanied by reduced in vivo hepatocyte apoptosis. In addition, wild type (WT), but not Sortilin-/- hepatocytes, had increased aSMase-dependent susceptibility to bile acid-induced apoptosis in vitro. Mechanistically, short-term IL-6 neutralization in bile duct-ligated WT mice decreased hepatic inflammation and reactive cholangiocyte-derived cytokines and chemokines, without affecting fibrosis, whereas pharmacological inhibition of aSMase activity was not sufficient to attenuate hepatic fibrosis. Only combined IL-6 and aSMase inhibition significantly reduced fibrosis in bile duct-ligated WT mice. We conclude that sortilin regulates cholestatic liver damage and fibrosis via effects on both aSMase activity and serum IL-6.

Adoptive Transfer of mRNA-Transfected T Cells Redirected against Diabetogenic CD8 T Cells Can Prevent Diabetes.

Chimeric major histocompatibility complex (MHC) molecules supplemented with T cell receptor (TCR) signaling motifs function as activation receptors and can redirect gene-modified T cells against pathogenic CD8 T cells. We have shown that ß2 microglobulin (ß2m) operates as a universal signaling component of MHC-I molecules when fused with the CD3-ζ chain. Linking the H-2Kd-binding insulin B chain peptide insulin B chain, amino acids 15-23 (InsB15-23) to the N terminus of ß2m/CD3-ζ, redirected polyclonal CD8 T cells against pathogenic CD8 T cells in a peptide-specific manner in the non-obese diabetic (NOD) mouse. Here, we describe mRNA electroporation for delivering peptide/ß2m/CD3-ζ genes to a reporter T cell line and purified primary mouse CD8 T cells. The peptide/ß2m/CD3-ζ products paired with endogenous MHC-I chains and transmitted strong activation signals upon MHC-I cross-linking. The reporter T cell line transfected with InsB15-23/ß2m/CD3-ζ mRNA was activated by an InsB15-23-H-2Kd-specific CD8 T cell hybrid only when the transfected T cells expressed H-2Kd. Primary NOD CD8 T cells expressing either InsB15-23/ß2m/CD3-ζ or islet-specific glucose-6-phosphatase catalytic subunit-related protein, amino acids 206-214 (IGRP206-214)/ß2m/CD3-ζ killed their respective autoreactive CD8 T cell targets in vitro. Furthermore, transfer of primary CD8 T cells transfected with InsB15-23/ß2m/CD3-ζ mRNA significantly reduced insulitis and protected NOD mice from diabetes. Our results demonstrate that mRNA encoding chimeric MHC-I receptors can redirect effector CD8 against diabetogenic CD8 T cells, offering a new approach for the treatment of type 1 diabetes.

Use of endoscopic septotomy for the treatment of late staple-line leaks after laparoscopic sleeve gastrectomy.

Background Staple-line leak following laparoscopic sleeve gastrectomy is a dire adverse event. While the treatment of acute and early leaks is well established, there is still dispute regarding late and chronic leaks. We describe an endoscopic approach combining septotomy and sleeve stricture dilation for treating late/chronic leaks. Methods Ten consecutive patients with late/chronic proximal leaks were treated at our center. The septum separating the sleeve lumen from the perigastric cavity was progressively dissected over several sessions and the downstream stricture was pneumatically dilated. The technical and clinical success rates were evaluated. Results: All ten patients were treated successfully. Eight patients had sleeve strictures that were dilated in conjunction with septotomy. A mean of five sessions over the course of 43 days was needed to complete treatment. In two patients with a small perigastric cavity and no stricture, septotomy was achieved with through-the-scope balloon dilation of the fistula. No adverse events were encountered. Conclusions Septotomy accompanied by stricture dilation seems highly effective and safe in late and chronic leaks following sleeve gastrectomy.

Comparative Study of Two Cohorts of Newly Diagnosed Crohn's Disease Demonstrates Change in Therapeutic Strategies.

BACKGROUND: There has been a paradigm shift in the treatment of Crohn's disease (CD) involving the rapid introduction of biologics and/or immunomodulators after diagnosis. We wished to assess whether this was applied to patients with newly diagnosed CD in a tertiary inflammatory bowel disease referral centre in Israel. METHODS: Newly diagnosed CD patients were stratified into 2 groups: the early group was diagnosed between 2005 and 2007 and the late group was diagnosed between 2010 and 2012. Baseline demographics, medical and surgical treatments, disease course and complications during those 2 periods were analyzed. RESULTS: Each group included 60 patients. Significantly higher rates of immunomodulators and biologics were administered to patients in the late group compared to the early group (81.7 and 36.7% compared to 56.7 and 18.3%, p = 0.004 and p = 0.021, respectively). On the other hand, steroid therapy was less prevalent in the late (36.7%) group compared to that of the early group (56.7%), p = 0.059. Medical and surgical CD outcomes, including exacerbations/hospitalizations and surgeries, were comparable for both groups. CONCLUSIONS: There was a change in treatment strategy between 2005-2007 and 2010-2012, as reflected in higher proportions of biologics/immunomodulators for patients with newly diagnosed CD. This was associated with a steroid-sparing effect.

Long-acting glucose-dependent insulinotropic polypeptide ameliorates obesity-induced adipose tissue inflammation.

Obesity induces low-grade chronic inflammation, manifested by proinflammatory polarization of adipose tissue innate and adaptive resident and recruited immune cells that contribute to insulin resistance (IR). The glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone that mediates postprandial insulin secretion and has anabolic effects on the adipose tissue. Importantly, recent evidence suggested that GIP is a potential suppressor of inflammation in several metabolic models. In this study, we aimed to investigate the immunoregulatory role of GIP in a murine model of diet-induced obesity (DIO) using the long-acting GIP analog [d-Ala(2)]GIP. Administration of [d-Ala(2)]GIP resulted in adipocytes of increased size, increased levels of adipose tissue lipid droplet proteins, indicating better lipid storage capacity, and reduced adipose tissue inflammation. Flow cytometry analysis revealed reduced numbers of inflammatory Ly6C(hi) monocytes and F4/80(hi)CD11c(+) macrophages, associated with IR. In addition, [d-Ala(2)]GIP reduced adipose tissue infiltration of IFN-γ-producing CD8(+) and CD4(+) T cells. Furthermore, [d-Ala(2)]GIP treatment induced a favorable adipose tissue adipokine profile, manifested by a prominent reduction in key inflammatory cytokines (TNF-α, IL-1ß, IFN-γ) and chemokines (CCL2, CCL8, and CCL5) and an increase in adiponectin. Notably, [d-Ala(2)]GIP also reduced the numbers of circulating neutrophils and proinflammatory Ly6C(hi) monocytes in mice fed regular chow or a high-fat diet. Finally, the beneficial immune-associated effects were accompanied by amelioration of IR and improved insulin signaling in liver and adipose tissue. Collectively, our results describe key beneficial immunoregulatory properties for GIP in DIO and reveal that its augmentation ameliorates adipose tissue inflammation and improves IR.

Sortilin deficiency improves the metabolic phenotype and reduces hepatic steatosis of mice subjected to diet-induced obesity.

BACKGROUND & AIMS: Sortilin traffics newly synthesized molecules from the trans-Golgi apparatus along secretory pathways to endosomes, lysosomes or to the cell surface. Sortilin trafficking of acid sphingomyelinase (aSMase) may regulate ceramide levels, a major modulator of insulin signalling. We therefore tested whether sortilin deficiency reduces hepatic and adipose tissue aSMase activity, improving insulin sensitivity in diet-induced obesity (DIO). METHODS: DIO in C57BL/6 (WT) and sortilin(-/-) mice was induced by high-fat diet feeding for 10 weeks. RESULTS: Sortilin(-/-) mice gained less body weight and less visceral fat, despite similar food intake compared to WT type mice and had enhanced glucose uptake in insulin tolerance tests, which was further corroborated by enhanced hepatic pAkt expression. Sortilin deficiency led to attenuated hepatic steatosis, reduced expression of genes involved in lipogenesis, ceramide synthesis and inflammatory cytokine production and reduced activity of ceramide synthase 5/6 (CerS5/6). Sortilin(-/-) mice had reduced hepatic aSMase activity under both steady-state and DIO. Likewise, sortilin(-/-) hepatocytes displayed hypersensitivity to insulin, due to enhanced insulin receptor downstream signalling. In adipose tissue, sortilin(-/-) mice exhibited lower expression of inflammatory cytokines and lower expression and activity of CerS5/6. As in liver, adipose tissue displayed increased insulin signalling, accompanied by attenuated aSMase activity. CONCLUSIONS: Sortilin deficiency induces a beneficial metabolic phenotype in liver and adipose tissue upon DIO, mediated in part by reduced aSMase activity.

Selective immunotargeting of diabetogenic CD4 T cells by genetically redirected T cells.

The key role played by islet-reactive CD8 and CD4 T cells in type 1 diabetes calls for new immunotherapies that target pathogenic T cells in a selective manner. We previously demonstrated that genetically linking the signalling portion of CD3-ζ onto the C-terminus of ß2 -microglobulin and an autoantigenic peptide to its N-terminus converts MHC-I complexes into functional T-cell receptor-specific receptors. CD8 T cells expressing such receptors specifically killed diabetogenic CD8 T cells, blocked T-cell-induced diabetes in immunodeficient NOD.SCID mice and suppressed disease in wild-type NOD mice. Here we describe the immunotargeting of CD4 T cells by chimeric MHC-II receptors. To this end we chose the diabetogenic NOD CD4 T-cell clone BDC2.5, which recognizes the I-A(g7) -bound 1040-31 mimotope. We assembled several constructs encoding I-A(g7) α- and ß-chains, the latter carrying mim or hen egg lysozyme peptide as control, each supplemented with CD3-ζ intracellular portion, either with or without its transmembrane domain. Following mRNA co-transfection of reporter B3Z T cells and mouse CD8 and CD4 T cells, these constructs triggered robust activation upon I-A(g7) cross-linking. A BDC2.5 T-cell hybridoma activated B3Z transfectants expressing the mimotope, but not the control peptide, in both configurations. Potent two-way activation was also evident with transgenic BDC2.5 CD4 T cells, but peptide-specific activation required the CD3-ζ transmembrane domain. Chimeric MHC-II/CD3-ζ complexes therefore allow the selective immunotargeting of islet-reactive CD4 T cells, which take part in the pathogenesis of type 1 diabetes.

Revision of restrictive bariatric procedures in elderly patients: results at a 5-year follow-up.

Revisional Bariatric Surgery (RBS) is increasing in popularity. Elderly patients (> 65 years old) are sometimes referred for RBS evaluation. The aim of this study is to evaluate outcomes of elderly patients undergoing RBS. A retrospective analysis of a cohort from a single-tertiary bariatric center. All elderly patients undergoing RBS after restrictive procedures between 2012 and 2022 were included. Thirty Nine patients undergoing RBS were included in the comparative analysis - 23 patients (57.5%) after adjustable gastric banding (s/p LAGB) and 16 patients (40%) after Sleeve Gastrectomy (s/p SG). The mean age and body mass index (BMI) of patients were comparable (67.2 ± 2.8 years and 38.3 ± 7.4, respectively). There was no difference in associated medical problems except reflux which was higher in s/p SG (68% vs. 13%; p < 0.001). The mean time interval between surgeries was 8.7 ± 5.1 years. The surgeries included One anastomosis gastric bypass (n = 22), SG (n = 8) and Roux-en-y gastric bypass (n = 9). Early major complication rates were comparable (4.3% and 12.5%; p = 0.36), and readmission rate was higher in patients s/p SG (p = 0.03). Ninety percent of patients were available to a follow-up of 59.8 months. The mean BMI and total weight loss was 29.2 and 20.3%, respectively with no difference between groups. The rate of patients with associated medical problems at last follow-up was significantly reduced. Five patients (12.5%) underwent revisional surgery due to complications during follow-up. In conclusion, RBS in the elderly is associated with a reasonable complication rate and is effective in terms of weight loss and improvement of associated medical problems in a 5-year follow-up.

Dipeptidyl peptidase 4-deficient rats have improved bile secretory function in high fat diet-induced steatosis.

BACKGROUND/AIMS: Rodent obesity models have been shown to display impaired bile secretory functions. We have shown that glucagon-like peptide 1 (GLP-1) attenuates hepatic lipogenesis, and in the present study we investigated whether GLP-1 also improves high fat diet-associated cholestatic injury. METHODS: Wild type (WT) and dipeptidyl peptidase 4-deficient rats (DPP4-) with chronic elevated serum levels of active GLP-1 were fed regular chow and a Western diet for 2 months. Primary hepatocytes were used to assess GLP-1 effects on mRNA expression and transcription of genes encoding bile acid synthesis enzymes and transporters. RESULTS: DPP4- exhibited attenuated liver injury as expressed by lower serum AST and ALT after 2 months of a Western diet. In addition, DPP4- had better insulin sensitivity, lower serum triglycerides, cholesterol and bile acids. Hepatic expression of cyp7A1, the rate limiting enzyme in conversion of cholesterol into bile acids, was strongly attenuated in DPP4- fed with a Western diet. Moreover, hepatic expression of bile transporter, ABCB11, was increased, facilitating a higher rate of bile secretion. Mechanistically, we showed that GLP-1 directly reduced basal and LXR-induced cyp7A1 mRNA expression and suppressed cyp7A1 transcription in transient transfection assays in primary hepatocytes. However, GLP-1 and its analog exendin 4 also induced mRNA expression of bile acid transporter ABCC3 in primary rat hepatocyte cultures. CONCLUSIONS: Our data suggest that GLP-1 analogs may serve as a novel therapeutic drug to alleviate obesity-induced liver injury by reducing bile acid synthesis and improving liver bile secretory function.

Endoscopic Transoral Outlet Reduction for the Treatment of Biliary Reflux Symptoms in Patients After One-Anastomosis Gastric Bypass-a Case Series.

PURPOSE: OAGB is the third most common bariatric surgery. Biliary reflux (BR) is an inherent complication of this unique anatomy, although there is still controversy regarding its significance and long-term risks including carcinogenesis. To date, there is no effective treatment for BR with conversion to RYGB reserved for refractory patients. TORe is an effective treatment for weight-regain and dumping syndrome after RYGB. We hypothesized that narrowing the anastomosis would decrease the amount of bile refluxate entering the stomach and esophagus in patients with BR symptoms after OAGB and alleviate symptoms. The purpose of this study is to evaluate the efficacy of TORe for the treatment of BR symptoms after OAGB. MATERIALS AND METHODS: BR was diagnosed clinically in patients after OAGB using the gastroesophageal reflux disease health-related quality of life (GERD-HRQL) instrument after treatment with high-dose proton pump inhibitor (PPI) excluded possible acid reflux. TORe was carried out using a suture pattern that narrowed and elongated the anastomosis. All patients were prospectively followed. RESULTS: Twelve patients, post-OAGB, underwent TORe for BR. Symptoms resolved in 9 (75%) patients. GERD-HRQL score at 6 months declined from an average of 33.7 (SD 1.9) before the procedure to 16.1 (SD 10, p < 0.001). In one case, a small perforation was identified during the procedure and was immediately sutured with no further sequela. DISCUSSION: TORe appears a safe and effective treatment for BR symptoms after OAGB, at least in the short term. Accurate tools for BR diagnosis, a larger cohort, and longer follow-up periods are needed to better show the effectiveness and durability of this treatment option.

Novel engineered B lymphocytes targeting islet-specific T cells inhibit the development of type 1 diabetes in non-obese diabetic Scid mice.

Introduction: In this study, we report a novel therapeutic approach using B lymphocytes to attract islet-specific T cells in the non-obese diabetic (NOD) mouse model and prevent the development of autoimmune diabetes. Rather than using the antibody receptor of B cells, this approach utilizes their properties as antigen-presenting cells to T cells. Methods: Purified splenic B cells were treated with lipopolysaccharide, which increases regulatory B (Breg) cell function, then electroporated with mRNA encoding either chimeric MHC-I or MHC-II molecules covalently linked to antigenic peptides. Immunoregulatory functions of these engineered B cells (e-B cells) were tested by in vitro assays and in vivo co-transfer experiments with beta-cell-antigen-specific CD8+ or CD4+ T cells in NOD.Scid mice, respectively. Results: The e-B cells expressing chimeric MHC-I-peptide inhibited antigen-specific CD8+ T-cell cytotoxicity in vitro. The e-B cells expressing chimeric MHC-II-peptide induced antigen-specific CD4+ T cells to express the regulatory markers, PD-1, ICOS, CTLA-4, Lag3, and Nrp1. Furthermore, e-B cells encoding the chimeric MHC-I and MHC-II peptide constructs protected NOD.Scid mice from autoimmune diabetes induced by transfer of antigen-specific CD8+ and CD4+ T cells. Discussion: MHC-peptide chimeric e-B cells interacted with pathogenic T cells, and protected the host from autoimmune diabetes, in a mouse model. Thus, we have successfully expressed MHC-peptide constructs in B cells that selectively targeted antigen-specific cells, raising the possibility that this strategy could be used to endow different protective cell types to specifically regulate/remove pathogenic cells.

The metabolic regulator PGC-1α links hepatitis C virus infection to hepatic insulin resistance.

BACKGROUND & AIMS: Chronic hepatitis C virus (HCV) infection is strongly associated with insulin resistance and diabetes mellitus. Peroxisome proliferator-activated receptor-gamma co-activator 1α (PGC-1α) is a transcriptional co-activator involved in the initiation of gluconeogenesis in the liver. Increased hepatic expression of PGC-1α has been implicated in insulin resistance. We investigated whether modulation of PGC-1α levels following HCV infection underlies HCV-associated hepatic insulin resistance. METHODS: HCV genomes were expressed in hepatoma cells followed by analysis of PGC-1α and gluconeogenesis levels. RESULTS: PGC-1α was robustly induced in HCV infected cells. PGC-1α induction was accompanied by an elevated expression of the gluconeogenic gene glucose-6 phosphatase (G6Pase) and increased glucose production. The induction of gluconeogenesis is HCV dependent, since interferon treatment abolishes PGC-1α and G6Pase elevation and decreases glucose output. Moreover, PGC-1α knockdown resulted in a significant reduction of G6Pase levels in HCV full length replicon cells, emphasizing the central role of PGC-1α in the exaggerated gluconeogenic response observed in HCV patients. Treatment of HCV replicon cells with the antioxidant N-acetylcysteine resulted in reduction of PGC-1α levels, suggesting that HCV-induced oxidative stress promoted PGC-1α upregulation. Finally, both PGC-1α and G6Pase RNA levels were significantly elevated in liver samples of HCV infected patients, highlighting the clinical relevance of these results. CONCLUSIONS: PGC-1α is robustly induced following HCV infection, resulting in an upregulated gluconeogenic response, thereby linking HCV infection to hepatic insulin resistance. Our results suggest that PGC-1α is a potential molecular target for the treatment of HCV-associated insulin resistance.