Gastroduodenal artery aneurysm - an extremely rare but insidious cause of abdominal pain: a case report.

An arterial aneurysm is a localized weakening of the artery wall that results in pathological dilatation. All intra-abdominal artery aneurysms are labeled as visceral artery aneurysms (VAA), apart from the aorto-iliac artery aneurysms. VAA´s are rare, gastroduodenal artery aneurysms (GDAA), constituting 1.5% of visceral artery aneurysms. A woman in her early 80s´ presented with chronic epigastric pain, weight loss, and nausea. Conservative management was unsuccessful. Imaging revealed a GDAA, prompting endovascular coil embolization. Subsequent evaluation confirmed Polyarteritis Nodosa (PAN), treated with rituximab. The report underscores the diagnostic challenges, emphasizing the need for a multidisciplinary approach using imaging and angiography. GDAA's potential life-threatening rupture necessitates prompt intervention, as illustrated in this case. The rare association with PAN, although infrequent, underscores the importance of considering underlying etiologies in multiple visceral aneurysms. Early diagnosis and intervention are pivotal for this uncommon yet potentially lethal condition.

Sleeve gastrectomy with duodenoileal bipartition using linear magnets: feasibility and safety at 1-year follow-up.

BACKGROUND: Single-anastomosis metabolic/bariatric surgery procedures may lessen the incidence of anastomotic complications. This study aimed to evaluate the feasibility and safety of performing side-to-side duodenoileal (DI) bipartition using magnetic compression anastomosis (MCA). In addition, preliminary efficacy, quality of life (QoL), and distribution of food through the DI bipartition were evaluated. METHODS: Patients with a body mass index (BMI) of ≥35.0 to 50.0 kg/m2 underwent side-to-side DI bipartition with the magnet anastomosis system (MS) with sleeve gastrectomy (SG). By endoscopic positioning, a distal magnet (250 cm proximal to the ileocecal valve) and a proximal magnet (first part of the duodenum) were aligned with laparoscopic assistance to inaugurate MCA. An isotopic study assessed transit through the bipartition. RESULTS: Between March 14, 2022 to June 1, 2022, 10 patients (BMI of 44.2 ± 1.3 kg/m2) underwent side-to-side MS DI. In 9 of 10 patients, an SG was performed concurrently. The median operative time was 161.0 minutes (IQR, 108.0-236.0), and the median hospital stay was 3 days (IQR, 2-40). Paired magnets were expelled at a median of 43 days (IQR, 21-87). There was no device-related serious advanced event within 1 year. All anastomoses were patent with satisfactory diameters after magnet expulsion and at 1 year. Respective BMI, BMI reduction, and total weight loss were 28.9 ± 1.8 kg/m2, 15.2 ± 1.8 kg/m2, and 34.2% ± 4.1%, respectively. Of note, 70.0% of patients reported that they were very satisfied. The isotopic study found a median of 19.0% of the meal transited through the ileal loop. CONCLUSION: Side-to-side MCA DI bipartition with SG in adults with class II to III obesity was feasible, safe, and efficient with good QoL at 1-year follow-up. Moreover, 19% of ingested food passed directly into the ileum.

Dietary Hemin Remodels Gut Microbiota and Mediates Tissue Inflammation and Injury in the Small Intestine.

SCOPE: Epidemiological studies have linked excessive red and processed meat intake to gut disorders. Under laboratory conditions, high heme content is considered the primary health risk factor for red meat. However, heme in meat is present in myoglobin, which is an indigestible protein, suggesting the different functions between myoglobin and heme. This study aims to explore how dietary myoglobin and heme affect gut health and microbiota differently. METHODS AND RESULTS: Histological and biochemical assessments as well as 16S rRNA sequencing are performed. Moderate myoglobin intake (equivalent to the recommended intake of 150 g meat per day for human) has beneficial effects on the duodenal barrier. However, a too high myoglobin diet (equivalent to intake of 3000 g meat per day for human) triggers duodenum injury and alters the microbial community. The hemin diet destroys intestinal tissue and ileal microbiota more significantly. The in vitro experiments further confirm that free heme exhibits high toxicity to beneficial gut bacteria while myoglobin promotes the growth and metabolism of Limosilactobacillus reuteri. CONCLUSION: Moderate intake of myoglobin or hemin is beneficial to intestinal health and microbiota, but too high amounts lead to tissue inflammation and injury in the small intestine by reshaping ileal microbiota.

Transcriptomic responses of rabbits to infections by precocious line and wild-type Eimeria media: revealing molecular signatures and pathway differences in liver and duodenum during the peak and terminal phases of oocyst production.

Eimeria media is a principal pathogen responsible for rabbit coccidiosis, targeting the rabbit's intestinal epithelial cells. This parasitism damages the intestinal mucosal barrier, initiating a systemic immune and inflammatory response that jeopardizes the sustainable growth of rabbit farming. To understand the implications of infection on the host's immune and metabolic responses, we employed RNA-Seq to analyze RNA from the liver and duodenum tissues of post-infected rabbits infected with both the precocious line and wild-type strain of E.media. Comprehensive transcriptomic analysis revealed that the two parasites exhibit divergent transcriptomic imprints on host tissues. While the precocious line predominantly modulates immune-centric pathways with significant differential gene enrichment, wild-type strain favors pathways that affect metabolism. In addition, our study pinpointed a set of genes that undergo significant modifications in response to these effects. These revelations grant a fresh avenue to probe deeper into the symbiotic intricacies of the E.media and its rabbit host.

Endoscopic submucosal dissection for the treatment of a large inflammatory fibroid polyp in the gastric antrum prolapsing into the duodenum: A case report.

RATIONALE: Inflammatory fibroid polyp (IFP), also known as Vanek tumor, is a rare, benign gastrointestinal lesion characterized by its inflammatory and fibroid histological features. IFP is often discovered incidentally during endoscopic examinations. It is exceedingly rare for an IFP to prolapse into the duodenum and results in incomplete obstruction of the pylorus. PATIENT CONCERNS: A 64-year-old male patient was admitted to the hospital with recurrent episodes of melena over a 6-month period, along with complaints of dizziness and fatigue in the past 10 days. DIAGNOSES: Gastroscopy showed a giant polypoid mass on the posterior wall of the gastric antrum, prolapsing into the duodenum. Abdominal computer tomography (CT) confirmed the tumor protruding into the duodenum. Pathologic examination of the resected specimen confirmed the IFP diagnosis. INTERVENTIONS: The giant tumor was completely and successfully excised using endoscopic submucosal dissection (ESD). After the surgery, the patient underwent acid suppression and fluid replenishment therapy. OUTCOMES: The patient responded well to ESD and was discharged in stable condition. As of the submission of the case report, there has been no recurrence of the tumor after a 5-month follow-up, and the patient is still under follow-up. LESSONS: While IFPs have traditionally been managed surgically, ESD demonstrates promising treatment outcomes, avoiding the need for surgical distal gastrectomy, and emerges as a safe and effective treatment option.

Postoperative delayed massive bleeding in gastric cancer: a case report.

BACKGROUND: Postoperative delayed bleeding of gastric cancer is a complication of radical gastrectomy with low incidence rate and high mortality. CASE PRESENTATION: This case report presents the case of a 63-year-old female patient of Mongolian ethnicity who was diagnosed with gastric malignancy during a routine medical examination and underwent Billroth's I gastric resection in our department. However, on the 24th day after the surgery, she was readmitted due to sudden onset of hematemesis. Gastroscopy, abdominal CT, and digital subtraction angiography revealed postoperative anastomotic fistula, rupture of the duodenal artery, and bleeding from the abdominal aorta. The patient underwent three surgical interventions and two arterial embolizations. The patient's condition stabilized, and she was discharged successfully. CONCLUSION: Currently, there are no specific guidelines for the diagnosis and treatment of pseudoaneurysms in the abdominal cavity resulting from gastric cancer surgery. Early digital subtraction angiography examination should be performed to assist in formulating treatment plans. Early diagnosis and treatment contribute to an improved overall success rate of rescue interventions.

A first-in-human clinical study of laparoscopic autologous myoblast sheet transplantation to prevent delayed perforation after duodenal endoscopic mucosal dissection.

BACKGROUND: The detection rate of superficial non-ampullary duodenal epithelial tumors (SNADETs) has recently been increasing. Large tumors may contain malignant lesions and early therapeutic intervention is recommended. Endoscopic mucosal dissection (ESD) is considered a feasible treatment modality, however, the anatomical and physiological characteristics of the duodenum create a risk of postoperative perforation after ESD. METHODS: To explore whether myoblast sheet transplantation could prevent delayed perforation after ESD, a first-in-human (FIH) clinical trial of laparoscopic autologous myoblast sheet transplantation after duodenal ESD was launched. Autologous myoblast sheets fabricated from muscle tissue obtained seven weeks before ESD were transplanted laparoscopically onto the serous side of the ESD. The primary endpoints were the onset of peritonitis due to delayed perforation within three days after surgery and all adverse events during the follow-up period. RESULTS: Three patients with SNADETs ≥ 20 mm in size underwent transplantation of a myoblast sheet onto the serous side of the duodenum after ESD. In case 1, The patient's postoperative course was uneventful. Endoscopy and abdominal computed tomography revealed no signs of delayed perforation. Despite incomplete mucosal closure in case 2, and multiple micro perforations during ESD in case 3, cell sheet transplantation could prevent the postoperative massive perforation after ESD, and endoscopy on day 49 after transplantation revealed no stenosis. CONCLUSIONS: This clinical trial showed the safety, efficacy, and procedural operability of this novel regenerative medicine approach involving transplanting an autologous myoblast sheet laparoscopically onto the serosa after ESD in cases with a high risk of delayed perforation. This result indicates the potential application of cell sheet medicine in treating various abdominal organs and conditions with minimal invasiveness in the future. TRIAL REGISTRATION: jRCT, jRCT2073210094. Registered November 8 2021, https://jrct.niph.go.jp/latest-detail/jRCT2073210094 .

Alterations of the duodenal mucosal microbiome in patients with metabolic dysfunction-associated steatotic liver disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease (NAFLD), is associated with altered gut microbiota; however, there has been a focus on fecal samples, which are not representative of the entire digestive tract. Mucosal biopsies of the descending duodenum were collected. Five regions of the 16S rRNA gene were amplified and sequenced. Other assessments conducted on the study subjects included body mass index, transient elastography, liver enzymes, and lipid profile. Fifty-one subjects (36 with MASLD and 15 controls) were evaluated. There was no significant difference between the two groups regarding alpha- or beta-diversity of the duodenal mucosal microbiota. Linear discriminant analysis effect size (LEfSe) analysis showed that the genera Serratia and Aggregatibacter were more abundant in the duodenal mucosa of patients with MASLD, whereas the duodenal mucosal microbiota of the healthy controls was enriched with the genus Petrobacter. PICRUSt2 analysis revealed that genes associated with amino acid degradation and carboxylate degradation were significantly enriched in the duodenal mucosal microbiota of patients with MASLD. Our findings reveal the duodenal mucosal microbiota in patients with MASLD, which could contribute to future studies investigating the causal relationship between duodenal microbiota and MASLD.

Four cases of non-Helicobacter pylori Helicobacter-infected gastritis with duodenal spiral bacilli.

BACKGROUND: Non-Helicobacter pylori Helicobacter (NHPH) is rarely detected in duodenal mucosa due to its preference for slightly acidic environments. Here, we report four cases of NHPH-infected gastritis with duodenal spiral bacilli, potentially NHPH, indicating the possibility of duodenal mucosal infection. CASE PRESENTATION: In every case, gastric mucosa showed endoscopic findings characteristic of NHPH-infected gastritis, and a mucosal biopsy was taken from the duodenal bulb; spiral bacilli were identified under microscopy using Giemsa staining. Case 1, a 46-year-old man, had diffuse spotty redness, mucosal edema, and multiple tiny erosions in the duodenal bulb, along with larger erosions in the second portion of the duodenum upon endoscopic examination. Histopathologically, moderate infiltration of mononuclear cells and neutrophils in the lamina propria and gastric epithelial metaplasia were observed. Case 2, a 54-year-old man, showed an elevated lesion, 1 cm in diameter, with multiple red spots and a few tiny erosions in the duodenal bulb. Histopathologically, mild inflammatory cell infiltration and gastric epithelial metaplasia were observed. In Case 3, a 52-year-old man, endoscopy revealed a flat elevated lesion, 7 mm in diameter, with multiple red spots and a few tiny erosions in the anterior wall of the duodenal bulb. Histopathologically, we observed moderate inflammatory cell infiltration in the gastric antrum and gastric epithelial metaplasia in the duodenal bulb. Case 4, a 40-year-old man, showed mild spotty redness in the duodenal bulb. Histopathologically, mild mononucleocyte infiltration and gastric epithelial metaplasia were observed. A single spiral bacillus was observed in Case 4 by microscopy. In all but Case 2, Helicobacter suis was identified in the gastric juice by polymerase chain reaction analysis. CONCLUSIONS: Spiral bacilli resembling NHPH may infect the duodenal mucosa, particularly the bulb, causing inflammation. Gastric contents entering the duodenum may reduce the intraduodenal pH, promoting NHPH survival and proliferation.

One-Anastomosis Gastric Bypass (OABG) vs. Single Anastomosis Duodeno-Ileal Bypass (SADI) as revisional procedure following Sleeve Gastrectomy: results of a multicenter study.

PURPOSE: Sleeve Gastrectomy (SG) is the most performed bariatric surgery, but a considerable number of patients may require revisional procedures for suboptimal clinical response/recurrence of weight (SCR/RoW). Conversion options include One-Anastomosis Gastric Bypass (OAGB) and Single Anastomosis Duodeno-Ileal Bypass (SADI). The study aims to compare SADI vs. OAGB as revisional procedures in terms of early and mid-term complications, operative time, postoperative hospital stay and clinical outcomes. METHODS: All patients who underwent OAGB or SADI as revisional procedures following SG for SCR/RoW at three high-volume bariatric centers between January 2014 and April 2021 were included. Propensity score matching (PSM) analysis was performed. Demographic, operative, and postoperative outcomes of the two groups were compared. RESULTS: One hundred and sixty-eight patients were identified. After PSM, the two groups included 42 OAGB and 42 SADI patients. Early (≤ 30 days) postoperative complications rate did not differ significantly between OAGB and SADI groups (3 bleedings vs. 0, p = 0.241). Mid-term (within 2 years) complications rate was significantly higher in the OAGB group (21.4% vs. 2.4%, p = 0.007), mainly anastomotic complications and reflux disease (12% of OAGBs). Seven OAGB patients required conversion to another procedure (Roux-en-Y Gastric Bypass-RYGB) vs. none among the SADI patients (p = 0.006). CONCLUSIONS: SADI and OAGB are both effective as revisional procedures for SCR/RoW after SG. OAGB is associated with a significantly higher rate of mid-term complications and a not negligible rate of conversion (RYGB). Larger studies are necessary to draw definitive conclusions.

Surgical management of duodenal crohn's disease.

BACKGROUND: Operative options for duodenal Crohn's disease include bypass, stricturoplasty, or resection. What factors are associated with operation selection and whether differences exist in outcomes is unknown. METHODS: Patients with duodenal Crohn's disease requiring operative intervention across a multi-state health system were identified. Patient and operative characteristics, short-term surgical outcomes, and the need for future endoscopic or surgical management of duodenal Crohn's disease were analyzed. RESULTS: 40 patients underwent bypass (n = 26), stricturoplasty (n = 8), or resection (n = 6). Median age of diagnosis of Crohn's disease was 23.5 years, and over half of the patients had undergone prior surgery for CD. Operation type varied by the most proximal extent of duodenal involvement. Patients with proximal duodenal CD underwent bypass operations more commonly than those with mid- or distal duodenal disease (p = 0.03). Patients who underwent duodenal stricturoplasty more often required concomitant operations for other sites of small bowel or colonic CD (63%) compared to those who underwent bypass (39%) or resection (33%). No patients required subsequent surgery for duodenal CD at a median follow-up of 2.8 years, but two patients required endoscopic dilation (n = 1 after stricturoplasty, n = 1 after resection). CONCLUSION: Patients who require surgery for duodenal Crohn's disease appear to have an aggressive Crohn's disease phenotype, represented by a younger age of diagnosis and a high rate of prior resection for Crohn's disease. Choice of operation varied by proximal extent of duodenal Crohn's disease.

Genome-wide analysis identifies MYH11 compound heterozygous variants leading to visceral myopathy corresponding to late-onset form of megacystis-microcolon-intestinal hypoperistalsis syndrome.

Megacystis-microcolon-hypoperistalsis-syndrome (MMIHS) is a rare and early-onset congenital disease characterized by massive abdominal distension due to a large non-obstructive bladder, a microcolon and decreased or absent intestinal peristalsis. While in most cases inheritance is autosomal dominant and associated with heterozygous variant in ACTG2 gene, an autosomal recessive transmission has also been described including pathogenic bialellic loss-of-function variants in MYH11. We report here a novel family with visceral myopathy related to MYH11 gene, confirmed by whole genome sequencing (WGS). WGS was performed in two siblings with unusual presentation of MMIHS and their two healthy parents. The 38 years-old brother had severe bladder dysfunction and intestinal obstruction, whereas the 30 years-old sister suffered from end-stage kidney disease with neurogenic bladder and recurrent sigmoid volvulus. WGS was completed by retrospective digestive pathological analyses. Compound heterozygous variants of MYH11 gene were identified, associating a deletion of 1.2 Mb encompassing MYH11 inherited from the father and an in-frame variant c.2578_2580del, p.Glu860del inherited from the mother. Pathology analyses of the colon and the rectum revealed structural changes which significance of which is discussed. Cardiac and vascular assessment of the mother was normal. This is the second report of a visceral myopathy corresponding to late-onset form of MMIHS related to compound heterozygosity in MYH11; with complete gene deletion and a hypomorphic allele in trans. The hypomorphic allele harbored by the mother raised the question of the risk of aortic disease in adults. This case shows the interest of WGS in deciphering complex phenotypes, allowing adapted diagnosis and genetic counselling.

Continuing Medical Education Questions: April 2024.

Article Title: The Spigelman Staging System and the Risk of Duodenal and Papillary Cancer in Familial Adenomatous Polyposis. A Systematic Review and Meta-Analysis.

Are there new biomarkers of the gastroduodenal microbiota useful in the diagnosis of coeliac disease in children? A pilot study.

The changing of microbiome could precede the development of coeliac disease (CeD). We compared the bacterial profile of microbiota of tissues collected simultaneously from the stomach and duodenum in newly diagnosed patients with CeD. Biopsies were collected from 60 children and adolescents aged 2-18 years: (1) 40 patients with CeD; (2) 20 children as control group. The evaluation of the bacterial microbiota was carried out by sequencing the V3-V4 regions of the 16S rRNA subunit, using next-generation sequencing (NGS). The composition of bacterial microbiota was correlated with clinical and blood parameters. The beta diversity analysis revealed a significant dissimilarity in the gastric samples between the CeD and control group (Bray-Curtis index, P = 0.008, and weighted UniFrac distance, P = 0.024). At L2 (phylum level), Campylobacterota was only present in the stomach of the CeD group. A comparison of the abundance of bacteria between the stomach and duodenum showed significant differences in 10 OTUs (operational taxonomic units) in the control and 9 OTUs in the CeD group at L6 (genus) and in 8 OTUs and in 6 OTUs, respectively, at L7 (species). A significant correlation was observed between the genus Novosphingobium in stomach of CeD group and possession of the DQ2.5 and DQ 8 allele, and in the duodenum - between the DQ 8 allele and the species Blautia wexlerae. Significant differences in selected, little-known genera of bacteria suggest their potential role as new biomarkers in the development of CeD. To fully understand the mechanism of CeD development in genetically predisposed individuals, it is necessary to take into account not only the abundance of a given genus or species of bacteria, but also the anatomical location of its occurrence.

Intraepithelial Lymphogram in the Diagnosis of Celiac Disease in Adult Patients: A Validation Cohort.

BACKGROUND: Celiac disease is a gluten-related pathology, highly prevalent and heterogeneous in its clinical presentation, which leads to delays in diagnosis and misdiagnosis. The analysis of duodenal intraepithelial lymphocytes (IELs) by flow cytometry (lymphogram) is emerging as a discriminative tool in the diagnosis of various forms of celiac disease (CD). AIMS: The aim of this study was to validate IEL lymphogram performance in the largest adult series to our knowledge, in support of its use as a diagnostic tool and as a biomarker of the dynamic celiac process. METHODS: This was a retrospective study including 768 adult patients (217 with active CD, 195 on a gluten-free diet, 15 potential CD patients, and 411 non-celiac controls). The IEL subset cut-off values were established to calculate the diagnostic accuracy of the lymphogram. RESULTS: A complete celiac lymphogram profile (≥14% increase in T cell receptor [TCR]γδ IELs and simultaneous ≤4% decrease in surface-negative CD3 [sCD3-] IELs) was strongly associated with active and potential forms in over 80% of the confirmed patients with CD, whereas the remaining patients with CD had partial lymphogram profiles (≥14% increase in TCRγδ or ≤4% decrease in sCD3- IELs), with lower diagnostic certainty. None of these patients had a non-celiac lymphogram. Quantifying the TCRγδ versus sCD3- imbalance as a ratio (≥5) is a discriminative index to discard or suspect CD at diagnosis. CONCLUSIONS: We have validated the IEL lymphogram's diagnostic efficiency (79% sensitivity, 98% specificity), with an LR+ accuracy of 36.2. As expected, the increase in TCRγδ IELs is a reliable marker for celiac enteropathy, while changes in sCD3- IEL levels throughout the dynamic CD process are useful biomarkers of mucosal lesions.

Modified Q-type purse-string suture duodenal stump embedding method for laparoscopic gastrectomy for gastric cancer.

OBJECTIVE: This study introduced the modified Q-type purse-string suture duodenal stump embedding method, a convenient way to strengthen the duodenum, and compared it to the conventional one to assess its efficacy and safety. METHODS: This retrospective analysis examined 612 patients who received laparoscopic gastrectomy for gastric Cancer at a single center. The patients were divided into Not Reinforced Group (n = 205) and Reinforced Group (n = 407) according to the surgical approach to the duodenal stump. The reinforced group was further divided into a modified Q-type purse-string suture embedding method group (QM, n = 232) and a conventional suture duodenal stump embedding method group (CM, n = 175) according to the methods of duodenal stump enhancement. Clinicopathological characteristics, operative variables, and short-term complications were documented and analyzed. RESULTS: The incidence of duodenal stump leakage(DSL) in the Not Reinforced Group was higher compared to the Reinforced Group, although the difference was not statistically significant [2.4% (5/205) vs 0.7% (3/407), p = 0.339]. Additionally, the Not Reinforced Group exhibited a higher rate of Reoperation due to DSL compared to the Reinforced Group [2 (1.0%) vs. 0, p = 0.046], with one patient in the Not Reinforced Group experiencing mortality due to DSL [1 (0.5%) vs 0, p = 0.158]. Subgroup analysis within the Reinforced Group revealed that the modified Q-type purse-string suture embedding group (QM) subgroup demonstrated statistically significant advantages over the conventional suture embedding group (CM) subgroup. QM exhibited shorter purse-string closure times (4.11 ± 1.840 vs. 6.05 ± 1.577, p = 0.001), higher purse-string closure success rates (93.1% vs. 77.7%, p = 0.001), and greater satisfaction with purse-string closure [224 (96.6%) vs 157 (89.7%), p = 0.005]. No occurrences of duodenal stump leakage were observed in the QM subgroup, while the CM subgroup experienced two cases [2 (1.1%)], though the difference was not statistically significant. Both groups did not exhibit statistically significant differences in secondary surgery or mortality related to duodenal stump leakage. CONCLUSION: Duodenal Stump Leakage (DSL) is a severe but low-incidence complication. There is no statistically significant relationship between the reinforcement of the duodenal stump and the incidence of DSL. However, laparoscopic reinforcement of the duodenal stump can reduce the severity of fistulas and the probability of Reoperation. The laparoscopic Q-type purse-string suture duodenal stump embedding method is a simple and effective technique that can, to some extent, shorten the operation time and enhance satisfaction with purse-string closure. There is a trend towards reducing the incidence of DSL, thereby improving patient prognosis to a certain extent.

Combined techniques for revealing the mechanism beneath the inhibition effects of pectin on gluten digestibility using static in vitro gastro-duodenal protocols.

In the current study, how pectin retards the digestibility of wheat gluten was investigated using a static in vitro gastric-duodenal model. The degree of protein hydrolysis was estimated using the o-phthaldialdehyde method, while the in vitro digestograms were mathematically fitted using a single first-order kinetics model. Peptides' profile, free amino acids compositions, gluten-pectin interactions and their effects on enzymatic activities of proteolytic enzymes as well as on the gluten secondary structures under digestive conditions were studied using combined techniques. Results showed that pectin could retard gluten digestibility through 1). preferential absorption to insoluble gluten aggregates by electrostatic interactions; 2). increasing the helix and reducing the ß-sheet content of the solubilized gluten protein fractions in terms of their secondary molecular structures; 3). reducing pepsin activity by forming negatively charged pectin-gluten mixtures which then interacted with the positively charged pepsin molecules. The deeper insight into gluten-pectin interactions and their influences on gluten digestibility under gastrointestinal conditions provides important clues for developing effective forms of dietary fiber to improve the nutritional benefits of plant protein in individuals.