Data_Sheet_1_Ductal Mucus Obstruction and Reduced Fluid Secretion Are Early Defects in Chronic Pancreatitis.PDF

<p>Objective: Defective mucus production in the pancreas may be an important factor in the initiation and progression of chronic pancreatitis (CP), therefore we aimed to (i) investigate the qualitative and quantitative changes of mucus both in human CP and in an experimental pancreatitis model and (ii) to correlate the mucus phenotype with epithelial ion transport function.</p><p>Design: Utilizing human tissue samples and a murine model of cerulein induced CP we measured pancreatic ductal mucus content by morphometric analysis and the relative expression of different mucins in health and disease. Pancreatic fluid secretion in CP model was measured in vivo by magnetic resonance cholangiopancreatography (MRCP) and in vitro on cultured pancreatic ducts. Time-changes of ductal secretory function were correlated to those of the mucin production.</p><p>Results: We demonstrate increased mucus content in the small pancreatic ducts in CP. Secretory mucins MUC6 and MUC5B were upregulated in human, Muc6 in mouse CP. In vivo and in vitro fluid secretion was decreased in cerulein-induced CP. Analysis of time-course changes showed that impaired ductal ion transport is paralleled by increased Muc6 expression.</p><p>Conclusion: Mucus accumulation in the small ducts is a combined effect of mucus hypersecretion and epithelial fluid secretion defect, which may lead to ductal obstruction. These results suggest that imbalance of mucus homeostasis may have an important role in the early-phase development of CP, which may have novel diagnostic and therapeutic implications.</p

Image_2_Ductal Mucus Obstruction and Reduced Fluid Secretion Are Early Defects in Chronic Pancreatitis.jpeg

<p>Objective: Defective mucus production in the pancreas may be an important factor in the initiation and progression of chronic pancreatitis (CP), therefore we aimed to (i) investigate the qualitative and quantitative changes of mucus both in human CP and in an experimental pancreatitis model and (ii) to correlate the mucus phenotype with epithelial ion transport function.</p><p>Design: Utilizing human tissue samples and a murine model of cerulein induced CP we measured pancreatic ductal mucus content by morphometric analysis and the relative expression of different mucins in health and disease. Pancreatic fluid secretion in CP model was measured in vivo by magnetic resonance cholangiopancreatography (MRCP) and in vitro on cultured pancreatic ducts. Time-changes of ductal secretory function were correlated to those of the mucin production.</p><p>Results: We demonstrate increased mucus content in the small pancreatic ducts in CP. Secretory mucins MUC6 and MUC5B were upregulated in human, Muc6 in mouse CP. In vivo and in vitro fluid secretion was decreased in cerulein-induced CP. Analysis of time-course changes showed that impaired ductal ion transport is paralleled by increased Muc6 expression.</p><p>Conclusion: Mucus accumulation in the small ducts is a combined effect of mucus hypersecretion and epithelial fluid secretion defect, which may lead to ductal obstruction. These results suggest that imbalance of mucus homeostasis may have an important role in the early-phase development of CP, which may have novel diagnostic and therapeutic implications.</p

Image_1_The Importance of Aquaporin 1 in Pancreatitis and Its Relation to the CFTR Cl- Channel.JPEG

<p>Aquaporins (AQPs) facilitate the transepithelial water flow involved in epithelial fluid secretion in numerous tissues; however, their function in the pancreas is less characterized. Acute pancreatitis (AP) is a serious disorder in which specific treatment is still not possible. Accumulating evidence indicate that decreased pancreatic ductal fluid secretion plays an essential role in AP; therefore, the aim of this study was to investigate the physiological and pathophysiological role of AQPs in the pancreas. Expression and localization of AQPs were investigated by real-time PCR and immunocytochemistry, whereas osmotic transmembrane water permeability was estimated by the dye dilution technique, in Capan-1 cells. The presence of AQP1 and CFTR in the mice and human pancreas were investigated by immunohistochemistry. Pancreatic ductal HCO₃^- and fluid secretion were studied on pancreatic ducts isolated from wild-type (WT) and AQP1 knock out (KO) mice using microfluorometry and videomicroscopy, respectively. In vivo pancreatic fluid secretion was estimated by magnetic resonance imaging. AP was induced by intraperitoneal injection of cerulein and disease severity was assessed by measuring biochemical and histological parameters. In the mice, the presence of AQP1 was detected throughout the whole plasma membrane of the ductal cells and its expression highly depends on the presence of CFTR Cl^- channel. In contrast, the expression of AQP1 is mainly localized to the apical membrane of ductal cells in the human pancreas. Bile acid treatment dose- and time-dependently decreased mRNA and protein expression of AQP1 and reduced expression of this channel was also demonstrated in patients suffering from acute and chronic pancreatitis. HCO₃^- and fluid secretion significantly decreased in AQP1 KO versus WT mice and the absence of AQP1 also worsened the severity of pancreatitis. Our results suggest that AQP1 plays an essential role in pancreatic ductal fluid and HCO₃^- secretion and decreased expression of the channel alters fluid secretion which probably contribute to increased susceptibility of the pancreas to inflammation.</p

Epidemiology and aetiology.

<p><b>A</b>. Sex distribution of AP cases. <b>B.</b> Age distribution of AP cases. <b>C.</b> AP severity groups. Mod: moderate; sev: severe. <b>D.</b> Age distribution of mild, moderate and severe AP cases and mortality. <b>E.</b> Overall mortality and distribution in the severity groups. p<0.001 was between the severe and other groups according to Fisher’s exact test. <b>F.</b> Days of hospitalization. Mann-Whitney U test with Bonferroni correction was used to compare the group pairs (p<0.001 between groups). <b>G.</b> Aetiology of AP. (<b>a:</b> p<0.001; <b>b:</b> p<0.001; <b>c:</b> p = 0.022, <b>d:</b> p = 0.030; <b>e:</b> p = 0.006; <b>f:</b> p<0.001; <b>g:</b> p = 0.011; <b>h:</b> p = 0.025).</p

Conservative therapy in AP.

<p><b>A.</b> Effect of fluid resuscitation on severity and mortality in the first 24 hours. The first dotted column represents the AP severity groups and mortality for each group in the entire cohort. Green: mild AP; yellow: moderate AP; red: severe AP; *: p = 0.030 (Fisher’s exact test on severity) versus the cohort (n = 8–185). A polynomial regression curve was fitted to demonstrate the mortality trend (n = 8–185). <b>B.</b> Enteral and parenteral feeding in AP. Mortality is shown for the severe AP group. NG: nasogastric feeding; NJ: nasojejunal feeding. <b>C.</b> Antibiotic therapy and its indications in AP. Table shows the indications for antibiotic therapy in the three severity groups. <b>D.</b> Probiotic therapy in AP.</p

Laboratory parameters in AP.

<p>The only parameters shown are where statistical differences were found between the AP severity groups. Green: mild AP; yellow: moderate AP; red: severe AP; <b>ns:</b> no significant difference (p>0.05); <b>+:</b> significant difference (p<0.05). In the left-hand panel of graphs, laboratory parameters were analysed by distinct values, grouped in ranges. The first dotted column represents the AP severity groups of the entire cohort. Here, the Chi-square test was employed. In the right-hand panel of graphs, the average laboratory parameters were compared in the three AP severity groups. Here, we used the Kruskal–Wallis test and Mann–Whitney U test with a Bonferroni correction to compare the pairs of groups under examination. <b>A.</b> White blood cell count (WBC, n = 21–204). A WBC count above 23,000/μL was associated with elevated risk of severe AP (<b>a:</b> p = 0.020), and the average WBC counts also showed significant differences between the mild versus moderate and mild versus severe AP groups (p<0.001). <b>B.</b> C-reactive protein (CRP: n = 32–144). CRP above 200 mg/L was associated with severe AP (<b>b:</b> p = 0.007). In addition, average CRP levels differed significantly between the mild versus moderate and mild versus severe AP groups (p<0.001). <b>C.</b> Procalcitonin (PCT, n = 5–54). PCT levels above 10 U/L were associated with elevated risk of severe AP (<b>c:</b> p<0.001); however, average PCT levels did not differ significantly between the three AP severity groups (p = 0.143). <b>D.</b> Calcium (Ca, n = 12–40). Ca levels below 2 mmol/L were associated with a heightened risk of severe AP (<b>d:</b> p = 0.004); however, the average calcium levels did not differ significantly between the three AP severity groups (p = 0.077). <b>E.</b> Triglycerides (Tg: n = 10–48). Tg levels above 41 mmol/L were associated with greater risk of severe AP (<b>e:</b> p = 0.012); however, average Tg levels did not differ significantly between the three AP severity groups (p = 0.153). <b>F.</b> Glucose. (n = 3–175). Significant differences in severity associated with particular glucose levels were not found (<b>f:</b> p = 0.191); however, average glucose levels differed significantly between the mild versus moderate and mild versus severe AP groups (p<0.001).</p

Diagnosis, anamnestic data and symptoms at admission.

<p><b>A.</b> Anamnestic data. The percentages of severe AP and mortality in severe AP are also shown in relation to alcohol consumption, smoking, diabetes and history of earlier AP. <b>B.</b> Relationship between time of onset of abdominal pain and presentation at ER units. <b>C.</b> Time of onset of abdominal pain and presentation at ER in the three severity groups and association with mortality in the severe group. <b>D.</b> Diagnosis. Distribution of diagnostic criteria in the overall cohort (pie chart) and in the three severity groups (table) and association with mortality in severe AP (table). P: pain; E: enzyme elevation; I: imaging alteration. ^O p = 0.189 (Fisher’s exact test) * p = 0.005 (Chi-square test) *** p<0.001 (Chi-square test). <b>E.</b> Type and localisation of abdominal pain. EPI: epigastric pain; URA: upper right abdomen; ULA: upper left abdomen; MD: middle abdomen; L: lower abdomen; D: diffuse. <b>F.</b> Symptoms in the entire cohort and in the severe AP group and association with mortality in the severe AP group. ^O p = 0.189 (Fisher’s exact test) ^OO p = 0.051 (Chi-square test) * p = 0.029 (Chi-square test).</p

Type, indication and outcome of interventions in AP.

<p>Data show the mortality differences between early and late interventions in AP.</p

Frequency of organ failure and mortality in AP.

<p><b>A.</b> Frequency of individual organ failure (pancreas, lung, cardiac, kidney and brain) and mortality in severe AP. <b>B.</b> Frequency of combined organ failure and mortality in severe AP. <b>C.</b> Frequency of pancreatic complications and mortality in AP. Mortality was only calculated in severe AP. <b>a:</b> p = 0.020 (Fisher’s exact test); <b>b:</b> p = 0.002 (Chi-square test); <b>c:</b> p = 0.043 (Fisher’s exact test); <b>d:</b> p = 0.003 (Chi-square test); <b>e:</b> p = 0.030 (Fisher’s exact test).</p

Primers used for reconstruction of recombinant SARS-CoV-2.

(XLSX)</p