[Diagnostic value of lipoprotein-associated phospholipase A2 in OPBR combined with gallbladder cholesterol deposition].

Objective: To study the diagnostic value of lipoprotein-associated phospholipase A2(LP-PL-A2) in occult pancreaticobiliary reflux(OPBR) combined with gallbladder cholesterol deposition. Methods: This was a case-control study. Forty-six patients with OPBR who underwent gallbladder surgery at Shanghai East Hospital from December 2020 to October 2021, with gallbladder cholesterol deposition as the case group and the remainder as the control group, were included for analysis of their clinical data. Results: There were 21 cases in the case group, with 10 males and 11 females, and aged (57±12) years; 25 cases in the control group, with 11 males and 14 females, and aged (56±10) years. Serum LP-PL-A2 [(551.62±128.69) U/L] was significantly higher in the case group than in the control group [(436.70±135.88) U/L] (t=-2.80,P<0.01).Univariate analysis showed that LP-PL-A2 was a risk factor for OPBR combined with gallbladder cholesterol deposition, OR(95%CI):1.007(1.002-1.012), P=0.011. The area under the receiver operating characteristic curve (ROC) curve was 0.742, P=0.005. Conclusion: LP-PL-A2 is of diagnostic value in OPBR combined with gallbladder cholesterol deposition.

Separation and Enrichment of Alkaloids from Coptidis Rhizoma and Euodiae Fructus by Macroporous Resin and Evaluation of the Effect on Bile Reflux Gastritis Rats.

The Zuojin Pill consists of Coptidis Rhizoma (CR) and Euodiae Fructus (EF). It has been a classic prescription for the treatment of gastrointestinal diseases in China since ancient times. Alkaloids are considered to be its main pharmacologically active substances. The authors of the present study investigated the feasibility of preparing high purity total alkaloids (TAs) from CR and EF extracts separately and evaluated the effect for the treatment of bile reflux gastritis (BRG). Coptis chinensis Franch. and Evodia rutaecarpa (Juss.) Benth. were used in the study. An optimized method for the enrichment and purification of TAs with macroporous resin was established. Furthermore, qualitative analysis by using ultra-high performance liquid chromatography coupled with electrospray ionization and quadrupole-time of flight mass spectrometry (UHPLC-ESI-QTOF-MS) was explored to identify the components of purified TAs. Thirty-one compounds, thirty alkaloids and one phenolic compound, were identified or tentatively assigned by comparison with reference standards or literature data. A method of ultra-high performance liquid chromatography coupled with diode array detector (UHPLC-DAD) for quantitative analysis was also developed. The contents of nine alkaloids were determined. Moreover, a rat model of BRG was used to investigate the therapeutic effect of the combination of purified TAs from CR and EF. Gastric pathologic examination suggested that the alkaloids' combination could markedly attenuate the pathological changes of gastric mucosa.

Free fatty acids and triglyceride change in the gallbladder bile of gallstone patients with pancreaticobiliary reflux.

BACKGROUND: Pancreaticobiliary reflux (PBR) causes chronic inflammation of the gallbladder mucosa and changes in the bile components, which are known to promote gallstone formation. This study aimed to investigate the bile biochemistry changes in gallstone patients with PBR and provide new clues for research on the involvement of PBR in gallstone formation. METHODS: Patients undergoing surgery for gallstones between December 2020 and May 2021 were eligible for inclusion. The bile biochemistry (including amylase, lipase, triglyceride, cholesterol, free fatty acids [FFAs], alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [ALP], and γ-glutamyl transferase [γ-GT]) of the included gallstone patients was analysed to determine correlations with PBR. RESULTS: In this study, 144 gallstone patients who underwent surgery were enrolled. Overall, 15.97 % of the patients had an increased bile amylase level, which was associated with older age and significantly higher bile levels of ALP, lipase, triglyceride, and FFAs. Positive correlations were observed between amylase and lipase, triglyceride, FFAs levels in the gallbladder bile. However, the bile levels of triglyceride, FFAs, and lipase were positively correlated with each other only in the PBR group and showed no significant correlation in the control (N) group. In addition, elevated bile FFAs levels were found to be an independent risk factor for gallbladder wall thickening. CONCLUSIONS: In conclusion, PBR-induced increase in FFAs and triglyceride in the gallbladder bile is a cause of gallstone formation, and an increase in bile ALP suggests the presence of cholestasis in PBR.

Increased levels of conjugated bile acids are associated with human bile reflux gastritis.

Bile acids (BAs) play essential roles in facilitating lipid digestion and absorption in the intestine. Gastric BAs were attributed to abnormal refluxing from duodenal compartments and correlated with the occurrence of gastric inflammation and carcinogenesis. However, the differences in gastric BAs between physiologically compromised and healthy individuals have not been fully investigated. In this study, gastric juice was collected from patients clinically diagnosed as gastritis with/without bile reflux and healthy subjects for BA profiles measurements. As a result, we found that the conjugated BAs became prominent components in bile reflux juice, whereas almost equal amounts of conjugated and unconjugated BAs existed in non-bile reflux and healthy juice. To investigate whether gastric BA changes were regulated by hepatic BA synthesis, C57BL/6J mice were intervened with GW4064/resin to decrease/increase hepatic BA synthesis. The results revealed that changes of gastric BAs were coordinated with hepatic BA changes. Additionally, gastric BAs were detected in several healthy mammals, in which there were no obvious differences between the conjugated and unconjugated BAs. Pigs were an exception. Thus, increased levels of conjugated BAs are associated with human bile reflux gastritis. Gastric conjugated BAs could become a panel of biomarkers to facilitate diagnosis of pathological bile reflux.

Bile reflux in patients with nerd is associated with more severe heartburn and lower values of mean nocturnal baseline impedance and chemical clearance.

BACKGROUND: Mean nocturnal baseline impedance (MNBI) and postreflux swallow-induced peristaltic wave (PSPW) index are novel impedance-based markers of reflux, but the effect of bile reflux on these metrics is unknown. The aim of this study was to evaluate bile reflux, MNBI, and PSPW index in patients with endoscopy-negative GERD partially responsive to PPI therapy. METHODS: All patients underwent off-PPI endoscopy, esophageal manometry, multichannel intraluminal impedance pH (MII-pH), and bile reflux monitoring. Abnormal esophageal acid exposure time (AET) was required for inclusion. Symptom intensity (using 10-cm visual analog scales), and conventional and novel MII-pH metrics were compared between patients with and without abnormal bile reflux. KEY RESULTS: We evaluated 42 NERD patients (29 males, mean age: 53.4 ± 13. years), mean AET 6.1 ± 2%, of which 21 had abnormal bile reflux (Group A, 10.2 ± 4.9%), and 21 had normal bile reflux (Group B, 0.4 ± 0.1%, P < .05 compared with Group A). Heartburn reporting on PPI was higher in Group A (7.2 ± 2.1 vs 5.8 ± 0.9; P = .002), but AET, number of reflux events (acidic and weakly acidic), did not differ between the two groups. However, both PSPW index and MNBI were lower in Group A (P < .001). A strong inverse linear correlation was found between bile reflux and both MNBI (Pearson's test; R = -0.714; P < .001) and PSPW index (R = -0.722; P < .001). CONCLUSIONS AND INFERENCES: Compared to acid reflux alone, the presence of bile in an acidic esophageal environment is associated with more severe heartburn, lesser relief from PPI therapy, higher impairment of esophageal mucosal integrity and less effective chemical clearance.

Long-term consequences of one anastomosis gastric bypass on esogastric mucosa in a preclinical rat model.

Although bariatric surgery is proven to sustain weight loss in morbidly obese patients, long-term adverse effects have yet to be fully characterized. This study compared the long-term consequences of two common forms of bariatric surgery: one-anastomosis gastric bypass (OAGB) and Roux-en-Y Gastric Bypass (RYGB) in a preclinical rat model. We evaluated the influence of biliopancreatic limb (BPL) length, malabsorption, and bile acid (BA) reflux on esogastric mucosa. After 30 weeks of follow-up, Wistar rats operated on RYGB, OAGB with a short BPL (15 cm, OAGB-15), or a long BPL (35 cm, OAGB-35), and unoperated rats exhibit no cases of esogastric cancer, metaplasia, dysplasia, or Barrett's esophagus. Compared to RYGB, OAGB-35 rats presented higher rate of esophagitis, fundic gastritis and perianastomotic foveolar hyperplasia. OAGB-35 rats also revealed the greatest weight loss and malabsorption. On the contrary, BA concentrations were the highest in the residual gastric pouch of OAGB-15 rats. Yet, no association could be established between the esogastric lesions and malabsorption, weight loss, or gastric bile acid concentrations. In conclusion, RYGB results in a better long-term outcome than OAGB, as chronic signs of biliary reflux or reactional gastritis were reported post-OAGB even after reducing the BPL length in a preclinical rat model.

The role of bile reflux and its related NF-κB activated pathway in progression of hypopharyngeal squamous cell cancer.

BACKGROUND: Prognosis for hypopharyngeal cancer is usually poor, and recurrence is common. Identifying new factors or related mechanisms that promote its progression may have clinical implications. Although, recent studies support bile reflux in hypopharyngeal carcinogenesis, it remains to be explored how bile and its related NF-κB activated pathway may further affects its progression in already established hypopharyngeal cancer. METHODS: Hypopharyngeal squamous cell carcinoma (HSCC) cell lines, FaDu and UMSCC11A, both negative for HPV, were repetitively exposed to bile acids (400 µM) at variable pH points (4.0, 5.5 and 7.0). Immunofluorescence, western blotting, luciferase assay, and qPCR were used to detect NF-κB activation, bcl-2 overexpression and gene expression. RESULTS: Bile at strongly acidic pH (4.0) potentiated the activation of NF-κB and its related mRNA phenotype in HSCC cells. IL-6, TNF-α, and BCL2 were found among the highest overexpressed genes as was previously found in HSCCs excised from patients with documented biliary reflux. An enhanced transcriptional activity of EGFR, RELA, STAT3, and WNT5Α and higher survival rates were observed in HSCC cells exposed to acidic bile compared to those exposed to bile at weakly acidic or neutral pH. CONCLUSION: Our novel findings support the observation that bile reflux has the potential for actively influencing the progression of hypopharyngeal cancer, mediated by NF-κB. In patients with hypopharyngeal cancer and known gastroesophageal reflux disease, antacid therapy may exert a role in furthering control of disease recurrence and progression.

Biliary reflux as a causal factor in hypopharyngeal carcinoma: New clinical evidence and implications.

BACKGROUND: Recent preclinical explorations strongly support the tumorigenic potential of bile on laryngopharyngeal mucosa. Herein, the authors describe, in bile-related human hypopharyngeal squamous cell carcinoma (HSCC), NF-κB-related messenger RNA (mRNA) and microRNA (miRNA) oncogenic phenotypes similar to those previously identified in acidic bile-exposed premalignant murine hypopharyngeal mucosa. METHODS: In this pilot study, the authors included human HSCC specimens paired with their adjacent normal tissue (ANT) derived from 3 representative patients with documented biliary laryngopharyngeal reflux (bile[+]) compared with 5 control patients without signs of bile reflux disease (bile[-]). Immunohistochemical, quantitative polymerase chain reaction, and miRNA analyses were used to detect the levels of activated NF-κB and expression levels of STAT3, EGFR, BCL2, WNT5A, IL-6, IL-1B, ΔNp63, cREL, TNF-α, TP53, NOTCH1, NOTCH2, NOTCH3, miR-21, miR-155, miR-192, miR-34a, miR-375, miR-451a, miR-489, miR-504, and miR-99a. RESULTS: Bile(+) HSCC demonstrated an intense NF-κB activation accompanied by significant overexpression of RELA(p65), EGFR, STAT3, BCL-2, cREL, ΔNp63, WNT5A, IL-6, and IL1B; upregulation of oncomir miR-21; and downregulation of tumor suppressor miR-375 compared with their respective ANTs. Bile(+) HSCC demonstrated significantly higher mRNA levels of all the analyzed genes, particularly RELA(p65), IL-6, EGFR, and TNF-α compared with bile(-) tumors. The miR-21/miR-375 ratio, which previously has been linked to tumor aggressiveness, was found to be >260-fold and >30-fold higher, respectively, in bile(+) HSCCs compared with their ANTs and bile(-) tumors. CONCLUSIONS: Although limitations apply to this pilot study due to the small number of patients with HSCC, the novel findings suggest that a history of bile as a component of esophageal reflux disease may represent an independent risk factor for hypopharyngeal carcinogenesis.

Bile Gastritis Following Laparoscopic Single Anastomosis Gastric Bypass: Pilot Study to Assess Significance of Bilirubin Level in Gastric Aspirate.

INTRODUCTION: Laparoscopic single anastomosis gastric bypass (SAGB) is increasingly performed for morbidly obese patients. AIM OF WORK: This pilot study aims primarily at evaluating the incidence of bile gastritis after SAGB. The occurrence of reflux oesophagitis and reflux symptoms were also assessed. PATIENTS AND METHODS: This study included 20 patients having no reflux symptoms. All patients underwent a SAGB as a primary bariatric procedure by a single surgeon. Patients included consented to have an upper GI endoscopy done at 6 months postoperatively. Gastric aspirate was sent for bilirubin level assessment. Gastric and esophageal biopsies were submitted for histopathology and campylobacter-like organism (CLO) test. RESULTS: In our study, the rate of bile gastritis was 30%. In 18 patients, the level of bilirubin in gastric aspirate seems to be related to the degree of mucosal inflammation. The remaining two patients had microscopic moderate to severe gastritis with normal aspirate bilirubin level. Two patients with bilirubin level in aspirate more than 20 mg/dl had severe oesophagitis, gastritis with erosions, and metaplasia. Relationship between bilirubin level and histopathological findings of gastric biopsy examination was statistically significant with a P value of 0.001. CONCLUSION: The incidence of bile gastritis in this cohort is higher than reported in the literature, and this may be worrying. The correlation between endoscopic findings and patients' symptoms is poor. Bilirubin level and pH in aspirate might be useful tools to confirm alkaline reflux. Its level might help to choose candidates for revision surgery after SAGB. This needs further validation with larger sample size.

The effect of laparoscopic cholecystectomy on the development of alkaline reflux gastritis and intestinal metaplasia.

BACKGROUND/AIMS: Laparoscopic cholecystectomy is the gold standard treatment for symptomatic gallstones. The goal of this study was to investigate the effect of cholecystectomy on alkaline reflux, histopathological changes in the gastric mucosa and H. pylori colonization. METHODOLOGY: Eighty five patients who had undergone laparoscopic cholecystectomy were included in this trial (20 males; 65 females; 44.97 ± 11.22 years). All the patients had an upper gastrointestinal endoscopy before and 6 months after the surgery and biopsies in the antrum and corpus were taken to investigate the mucosal changes and assay for the presence of H. pylori. RESULTS: At 6 months post-surgery, the presence of bile in the fasting gastric fluid and an increase in the endoscopic gastritis findings were detected. While none of the patients had chemical gastritis prior to surgery, 7 patients were diagnosed with this condition after surgery. Intestinal metaplasia was detected in 6 patients prior to surgery and 20 patients after surgery. H. pylori was observed in 64 patients before surgery and 52 patients after surgery. CONCLUSIONS: An increase in duodenogastric reflux, alkaline reflux gastritis and intestinal metaplasia, and a reduction in H. pylori colonization were observed to occur post-cholecystectomy.

Molecular changes in the esophageal epithelium after a subchronic exposure to cigarette smoke in the presence of bile-acid reflux.

BACKGROUND: Gastroesophageal reflux of bile acids plays an important role in the development of Barrett's esophagus (BE)-associated esophageal adenocarcinoma (EAC). Cigarette smoke has been demonstrated to exacerbate the effects of reflux and thus the initial stages of EAC carcinogenesis. To date, no in vivo studies have been conducted to look at the concomitant effects of cigarette smoke and bile acids on EAC incidence. METHODS: In this pilot study, rats that underwent esophagoduodenal anastomosis (EDA) surgery to induce reflux were exposed to whole-body cigarette smoke 3 weeks after surgery. Smoke exposure (135 mg/m³/day) was done for 4 h/day for 5 consecutive days and animals were euthanized after a 48-h recovery period. RESULTS: Exposure to EDA-smoke accelerated the development of BE when compared to EDA-air. The presence of reflux caused a significant 3.5-fold increase in nuclear factor-κB-inducing kinase (NIK) staining (1.47 ± 0.6; p = 0.01). Animals with both reflux and smoking had the highest (10-fold; 4 ± 0.9) induction of cyclooxygenase-2 (COX-2) expression (p < 0.05). Similarly, there was a 10-fold increase in 4-aminobiphenyl (4-ABP) protein adducts identified in all smoke-exposed animals (p < 0.01). CONCLUSION: Cigarette smoke aggravates reflux-induced BE and potentially accelerates the progression of BE to EAC through the loss of manganese superoxide dismutase (MnSOD), and overexpression of NF-κB- and COX-2-mediated factors.

Induction of MUC5AC mucin by conjugated bile acids in the esophagus involves the phosphatidylinositol 3-kinase/protein kinase C/activator protein-1 pathway.

BACKGROUND: Bile reflux contributes to the development of esophageal injury and neoplasia. The mucin 5AC (MUC5AC) is absent in the normal squamous epithelium of the esophagus but is strongly expressed in Barrett esophagus (BE). The objective of this study was to determine whether and how bile acids influence the expression of MUC5AC in the esophagus. METHODS: MUC5AC expression was studied by immunohistochemistry and immunoblotting in human tissues, in tissues from a rat model of BE, and in SKGT-4 cultured esophageal epithelial cells. MUC5AC transcription was studied by real-time polymerase chain reaction and transient transfection assays. RESULTS: MUC5AC was absent from normal squamous epithelium but was present in 100% of Barrett specimens and in 61.5% of human esophageal adenocarcinoma tissues that were examined. MUC5AC protein expression was induced to a greater degree by conjugated bile acids than by unconjugated bile acids, and this occurred at the transcriptional level. In the rat reflux model, MUC5AC mucin was expressed abundantly in tissues of BE stimulated by duodenoesophageal reflux. Conjugated bile acids induced AKT phosphorylation in SKGT-4 cells but had no effect on extracellular signal-regulated protein kinases 1 and 2, c-Jun N-terminal kinase, or protein-38 kinase phosphorylation. The phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 and a dominant-negative protein kinase C (AKT) construct prevented the induction of MUC5AC by conjugated bile acids. Transactivation of AP-1 by conjugated bile acids coincided with MUC5AC induction, and cotransfection with a dominant-negative activator protein-1 (AP-1) vector decreased MUC5AC transcription and its induction. CONCLUSIONS: Conjugated bile acids in the bile refluxate contribute to MUC5AC induction in the esophagus. This occurs at the level of transcription and involves activation of the PI3K/AKT/AP-1 pathway.

Pancreatobiliary reflux and the length of a common channel.

BACKGROUND/PURPOSE: Gallbladder cancer occurs frequently in patients with pancreaticobiliary maljunction due to pancreatobiliary reflux. Pancreatobiliary reflux is also detected in some patients with a relatively long common channel. This study aimed to clarify the correlation between pancreatobiliary reflux and the length of a common channel. METHODS: Two hundred and three patients, in whom both the length of a common channel and amylase level in the bile were measured, were enrolled from nine centers. RESULTS: Bile amylase level was correlated with the length of a common channel (P < 0.01). The minimum length of a common channel that could induce a markedly elevated amylase level in the bile (>1,000 mg/dl) was determined as 5 mm. We redefined high confluence of pancreatobiliary ducts (HCPBD) as cases with a common channel > or = 5 mm, in which the communication between the pancreatic and bile ducts was occluded with the sphincter contraction. Gallbladder cancer was found in 20% of 56 redefined HCPBD patients. Bile amylase level >1,000 mg/dl and biliopancreatic reflux were detected in 79 and 95% of the patients, respectively. CONCLUSIONS: Patients with a common channel > or = 5 mm (redefined HCPBD) should be monitored for the development of gallbladder cancer, as they frequently showed significant pancreatobiliary reflux.

Aberrant epithelial-mesenchymal Hedgehog signaling characterizes Barrett's metaplasia.

BACKGROUND & AIMS: The molecular mechanism underlying epithelial metaplasia in Barrett's esophagus remains unknown. Recognizing that Hedgehog signaling is required for early esophageal development, we sought to determine if the Hedgehog pathway is reactivated in Barrett's esophagus, and if genes downstream of the pathway could promote columnar differentiation of esophageal epithelium. METHODS: Immunohistochemistry, immunofluorescence, and quantitative real-time polymerase chain reaction were used to analyze clinical specimens, human esophageal cell lines, and mouse esophagi. Human esophageal squamous epithelial (HET-1A) and adenocarcinoma (OE33) cells were subjected to acid treatment and used in transfection experiments. Swiss Webster mice were used in a surgical model of bile reflux injury. An in vivo transplant culture system was created using esophageal epithelium from Sonic hedgehog transgenic mice. RESULTS: Marked up-regulation of Hedgehog ligand expression, which can be induced by acid or bile exposure, occurs frequently in Barrett's epithelium and is associated with stromal expression of the Hedgehog target genes PTCH1 and BMP4. BMP4 signaling induces expression of SOX9, an intestinal crypt transcription factor, which is highly expressed in Barrett's epithelium. We further show that expression of Deleted in Malignant Brain Tumors 1, the human homologue of the columnar cell factor Hensin, occurs in Barrett's epithelium and is induced by SOX9. Finally, transgenic expression of Sonic hedgehog in mouse esophageal epithelium induces expression of stromal Bmp4, epithelial Sox9, and columnar cytokeratins. CONCLUSIONS: Epithelial Hedgehog ligand expression may contribute to the initiation of Barrett's esophagus through induction of stromal BMP4, which triggers reprogramming of esophageal epithelium in favor of a columnar phenotype.

Bile acid reflux contributes to development of esophageal adenocarcinoma via activation of phosphatidylinositol-specific phospholipase Cgamma2 and NADPH oxidase NOX5-S.

Gastroesophageal reflux disease complicated by Barrett's esophagus (BE) is a major risk factor for esophageal adenocarcinoma (EA). However, the mechanisms of the progression from BE to EA are not fully understood. Besides acid reflux, bile acid reflux may also play an important role in the progression from BE to EA. In this study, we examined the role of phosphatidylinositol-specific phospholipase C (PI-PLC) and a novel NADPH oxidase NOX5-S in bile acid-induced increase in cell proliferation. We found that taurodeoxycholic acid (TDCA) significantly increased NOX5-S expression, hydrogen peroxide (H(2)O(2)) production, and cell proliferation in EA cells. The TDCA-induced increase in cell proliferation was significantly reduced by U73122, an inhibitor of PI-PLC. PI-PLCbeta1, PI-PLCbeta3, PI-PLCbeta4, PI-PLCgamma1, and PI-PLCgamma2, but not PI-PLCbeta2 and PI-PLCdelta1, were detectable in FLO cells by Western blot analysis. Knockdown of PI-PLCgamma2 or extracellular signal-regulated kinase (ERK) 2 mitogen-activated protein (MAP) kinase with small interfering RNAs (siRNA) significantly decreased TDCA-induced NOX5-S expression, H(2)O(2) production, and cell proliferation. In contrast, knockdown of PI-PLCbeta1, PI-PLCbeta3, PI-PLCbeta4, PI-PLCgamma1, or ERK1 MAP kinase had no significant effect. TDCA significantly increased ERK2 phosphorylation, an increase that was reduced by U73122 or PI-PLCgamma2 siRNA. We conclude that TDCA-induced increase in NOX5-S expression and cell proliferation may depend on sequential activation of PI-PLCgamma2 and ERK2 MAP kinase in EA cells. It is possible that bile acid reflux present in patients with BE may increase reactive oxygen species production and cell proliferation via activation of PI-PLCgamma2, ERK2 MAP kinase, and NADPH oxidase NOX5-S, thereby contributing to the development of EA.

Bile and acid reflux in the pathogenesis of reflux oesophagitis in children.

AIM: The aim of this study was to investigate the role of bile and acid reflux in the pathogenesis of reflux oesophagitis (RE) in children. METHODS: A total of 44 patients aged 5-17 years with gastro-oesophageal reflux symptoms were enrolled. Simultaneous 24-h oesophageal Bilitec 2000 (Medtronic Instruments, Minneapolis, MN, USA) bilirubin monitoring and pH monitoring, in biopsy of oesophageal mucosa by gastro-endoscopy, were performed in all patients. RESULTS: According to the diagnostic criteria of pathological acid reflux and pathological bile reflux, 10 of 44 cases (22.7%) had acid reflux, 10 (22.7%) had isolated bile reflux, 16 (36.4%) had mixed acid and bile reflux, and the other eight (18.2%) had no reflux. Significant difference was observed in the ratio of different patterns of reflux between the RE group (26 cases) and the non-erosive reflux disease (NERD) group (18 cases) (chi(2) = 9.096, P < 0.01). All the parameters of acid reflux in the RE group were higher significantly than that in the NERD group (P < 0.05 or P < 0.01). A total of 20 out of 26 cases (76.9%) with RE had oesophageal acid reflux as against six out of 18 cases (33.3%) in patients with NERD (P < 0.01). The difference of each parameter of bile reflux had not reached significance between the two groups. CONCLUSIONS: Mixed reflux is the predominant form of reflux in the causation of oesophageal mucosal injury in children. Isolated bile reflux also plays a role in the development of RE, although only in patients without acid reflux.

Biliary reflux and non-acid reflux are two distinct phenomena: a comparison between 24-hour multichannel intraesophageal impedance and bilirubin monitoring.

OBJECTIVE: Duodenogastroesophageal reflux (DGER) can greatly increase microscopic and macroscopic esophageal mucosal damage caused by acid. The aim of this study was simultaneously to assess the chemical composition of DGER by detecting bilirubin in the refluxate by means of Bilitec and describe its pH and physical properties by impedance monitoring, in order to prove that non-acid reflux and biliary reflux are two distinct phenomena. MATERIAL AND METHODS: Twenty patients with gastroesophageal reflux disease (GERD) with symptoms refractory to conventional proton-pump inhibitor (PPI) therapy or with atypical GERD symptoms were included in the study. All patients underwent upper gastrointestinal endoscopy and simultaneous Bilitec and intraeosophageal impedance (IIM) and pH monitoring. In the majority of patients (16/20), the tests were performed while assuming a standard PPI dose. RESULTS: Pathological bilirubin exposure, as defined by intraesophageal bilirubin absorbance above 0.14 for more than 3.9% of the time, was present in 9 cases, 6 of them with normal values of non-acid reflux, as detected by IIM. A pathological non-acid reflux, as defined by an IIM showing a percentage time with non-acid reflux greater than 1.4%, was observed in 5 patients, 2 of whom had no pathological biliary reflux, as detected by Bilitec. No correlation was found between the two indices, as expressed by an r-value of -0.12 (p>0.05). CONCLUSIONS: Our study confirms that biliary reflux and non-acid reflux as detected by Bilitec and by IIM, respectively, are two distinct phenomena that require different techniques in order to be assessed in humans.

Regulation of the human mucin MUC4 by taurodeoxycholic and taurochenodeoxycholic bile acids in oesophageal cancer cells is mediated by hepatocyte nuclear factor 1alpha.

MUC4 (mucin 4) is a membrane-bound mucin overexpressed in the early steps of oesophageal carcinogenesis and implicated in tumour progression. We previously showed that bile acids, main components of gastro-oesophageal reflux and tumour promoters, up-regulate MUC4 expression [Mariette, Perrais, Leteurtre, Jonckheere, Hemon, Pigny, Batra, Aubert, Triboulet and Van Seuningen (2004) Biochem. J. 377, 701-708]. HNF (hepatocyte nuclear factor) 1alpha and HNF4alpha transcription factors are known to mediate bile acid effects, and we previously identified cis-elements for these factors in MUC4 distal promoter. Our aim was to demonstrate that these two transcription factors were directly involved in MUC4 activation by bile acids. MUC4, HNF1alpha and HNF4alpha expressions were evaluated by immunohistochemistry in human oesophageal tissues. Our results indicate that MUC4, HNF1alpha and HNF4alpha were co-expressed in oesophageal metaplastic and adenocarcinomatous tissues. Studies at the mRNA, promoter and protein levels indicated that HNF1alpha regulates endogenous MUC4 expression by binding to two cognate cis-elements respectively located at -3332/-3327 and -3040/-3028 in the distal promoter. We also showed by siRNA (small interfering RNA) approach, co-transfection and site-directed mutagenesis that HNF1alpha mediates taurodeoxycholic and taurochenodeoxycholic bile acid activation of endogenous MUC4 expression and transcription in a dose-dependent manner. In conclusion, these results describe a new mechanism of regulation of MUC4 expression by bile acids, in which HNF1alpha is a key mediator. These results bring new insights into MUC4 up-regulation in oesophageal carcinoma associated with bile reflux.

Dynamic study of pancreaticobiliary reflux using secretin-stimulated magnetic resonance cholangiopancreatography in patients with choledochal cysts.

BACKGROUND/PURPOSE: Refluxes through pancreaticobiliary maljunctions play an important role in the pathophysiology of choledochal cysts. Dynamic studies of the pancreaticobiliary tract were performed using secretin-stimulated magnetic resonance cholangiopancreatography. METHODS: Six patients with choledochal dilation were recruited for this study. Four patients exhibited cystic and 2 exhibited fusiform dilatation of the common bile duct (CBD). Magnetic resonance cholangiopancreatography images were obtained every minute during the 15-minute period after secretin stimulation. The sequential morphological changes in the biliary trees, pancreas, and duodenum were assessed, and the total pixel values of these organs were measured for each image, then plotted as a ratio against the baseline image. RESULTS: In 2 cases involving cystic dilatation, the intensity of bile duct images continued to rise after secretin stimulation. In a case involving fusiform dilatation, a transitory elevation in CBD intensity was observed. In 3 cases involving fusiform or cystic dilatation, the intensity of CBD did not change notably. In all cases, the duodenum was filled well after secretin stimulation. CONCLUSIONS: The sustained elevation in bile duct intensity after secretin stimulation indicates reflux and bile stasis. Transitory elevation may indicate reflux without stasis. This method allows assessment of the dynamics of pancreatic and bile fluid under more physiologic condition.

Effects and mechanism of changes of local neurotransmitters in rats' pylorus and bile reflux to the stomach with stress ulcer.

Stress ulcer occurs primarily in severe conditions, with a high incidence and mortality in intensive care units. However, studies on the association between stress ulcer and bile reflux to the stomach with stress ulcer are still inconclusive. Therefore, our research aimed to determine whether or not bile reflux exists during stress ulcer and then to investigate the effects and mechanism of changes of pyloric local neurotransmitters on bile reflux in such circumstances so as to provide a new pathway for clinical intervention. Cold water immersion was used to copy the stress ulcer model of rats. Sixty-five adult Sprague-Dawley rats of either sex were randomly divided into three groups: the normal control group (n = 10), the stress group (n = 30), and the antagonist group (n = 25). The gastric ulcer index, pH, and bile acid of gastric juice were measured before and after stress. Radio Immunoassay Detection Kit and Biochemic Detection Kit were used to measure local contents of CGRP (calcitonin gene-related peptide) and nitric oxide, respectively, in rats' pylorus. The local contents of nitric oxide in rats' pylorus reached a maximum at 1 hr after stress. The bile acid and pH of gastric juice peaked at 2 hr after stress and the ulcer index peaked at 4 hr after stress. But the local contents of CGRP in rats' pylorus decreased to the minimum at 4 hr after stress. The bile acid and ulcer index in the L-NAME group were significantly lower than in the antagonist control group. However, the bile acid in the hCGRP8-37 group was less than in the antagonist control group. Compared with hCGRP8-37 group, there was a significant reduction in bile acid in the L-NAME group. There was a significant reduction in the ulcer index of the hCGRP8-37 group compared with the L-NAME group and the antagonist control group. There was a certain kind of positive correlation between nitric oxide in rats' pylorus and bile acid to the stomach, for nitric oxide could loosen the pyloric sphincter and increase the bile acid to the stomach. L-NAME might reduce the local nitric oxide contents in rats' pylorus so that bile acid to the stomach might be decreased, obviously with a looser tight pyloric sphincter. Meanwhile, the CGRP in rats' pylorus was negatively associated with the ulcer index, hence CGRP might protect gastric mucosa under stress conditions.