Diabetes aggravates acute pancreatitis and inhibits pancreas regeneration in mice

Machine learning predicts acute respiratory failure in pancreatitis patients: A retrospective study

PURPOSE

The purpose of the research is to design an algorithm to predict the occurrence of acute respiratory failure (ARF) in patients with acute pancreatitis (AP).

METHODS

We collected data on patients with AP in the Medical Information Mart for Intensive Care IV database. The enrolled observations were randomly divided into a 70 % training cohort and a 30 % validation cohort, and the observations in the training cohort were divided into ARF and non-ARF groups. Feature engineering was conducted using random forest (RF) and least absolute shrinkage and selection operator (LASSO) methods in the training cohort. The model building included logistic regression (LR), decision tree (DT), k-nearest neighbours (KNN), naive bayes (NB) and extreme gradient boosting (XGBoost). Parameters for model evaluation include receiver operating characteristic (ROC) curve, precision-recall curve (PRC), calibration curves, positive predictive value (PPV), negative predictive value (NPV), true positive rate (TPR), true negative rate (TNR), accuracy (ACC) and F1 score.

RESULTS

Among 4527 patients, 445 patients (9.8 %) experienced ARF. Ca, ALB, GLR, WBC, AG and BUN have been included in the prediction model as features for predicting ARF. The AUC of XGBoost were 0.86 (95 %CI 0.84-0.88) and 0.87 (95 %CI 0.84-0.90) in the training and validation cohorts. In the training cohort, XGBoost demonstrates a true positive rate (TPR) of 0.662, a true negative rate (TNR) of 0.884, a positive predictive value (PPV) of 0.380, a negative predictive value (NPV) of 0.960, an accuracy (ACC) of 0.862, and an F1 score of 0.483. In the validation cohort, XGBoost shows a TPR of 0.620, a TNR of 0.895, a PPV of 0.399, an NPV of 0.955, an ACC of 0.867, and an F1 score of 0.486.

CONCLUSION

The XGBOOST model demonstrates good discriminatory ability, which enables clinicians to ascertain the probability of developing ARF in AP patients.

Encapsulation of telmisartan inside insulinoma-cell-derived extracellular vesicles outperformed biomimetic nanovesicles in modulating the pancreatic inflammatory microenvironment

Diabetes mellitus (DM) is a chronic metabolic condition, characterized by hyperglycaemia, oxidative imbalance, pancreatic β-cell death, and insulin insufficiency. Angiotensin II (Ang II) increases oxidative stress, inflammation, and apoptosis, and Ang II type 1 receptor (AT1R) blockers (ARBs) can ameliorate inflammatory response and oxidative stress. However, like other small-molecule drugs, free ARBs show poor in vivo efficacy and dose-limiting toxicities. Hence, in this study, we developed nano-formulations of telmisartan (TEL), an ARB, by encapsulating it inside a murine insulinoma cell-derived extracellular vesicle (nanoTEL) and a bio-mimetic lipid nanovesicle (lipoTEL). Both nano-formulations showed spherical morphology and sustained release of TEL. In vitro, nanoTEL restored oxidative equilibrium, attenuated reactive oxygen species levels, enhanced the uptake of glucose analogue, and increased the expression of glucose transporter protein 4 better than lipoTEL. In a streptozotocin-induced murine model of diabetes, nanoTEL lowered blood glucose levels, improved glucose tolerance, and promoted insulin synthesis and secretion significantly better than lipoTEL. Moreover, nanoTEL was found superior in ameliorating the pancreatic inflammatory microenvironment by regulating NF-κBp65, HIF-1α, and PPAR-γ expression; modulating IL-1β, IL-6, tumor necrosis factor-α, IL-10, and IL-4 levels and inducing the polarization of macrophage from M1 to M2. Further, nanoTEL administration induced angiogenesis and promoted the proliferation of pancreatic cells to restore the structural integrity of the islets of Langerhans more efficiently than lipoTEL. These findings collectively suggest that nanoTEL outperforms lipoTEL in restoring the function of pancreatic β-cells by modulating the pancreatic inflammatory microenvironment and show potential for the treatment of DM.

Clinical Outcomes of Diabetes Mellitus on Moderately Severe Acute Pancreatitis and Severe Acute Pancreatitis

Objective

To analyze the influence of diabetes mellitus on the clinical outcomes of moderately severe acute pancreatitis (MSAP) and severe acute pancreatitis (SAP).

Methods

This retrospective study included patients diagnosed with MSAP and SAP at Shanxi Bethune Hospital from January 1, 2017, to December 31, 2021. Clinical data were collected, including patient demographics, 24-hour laboratory indicators, and inflammation indices. Propensity score matching (PSM) was used to compare outcomes before and after matching. Patients were randomized into training and validation sets (7:3) to develop and validate a clinical prediction model for infected pancreatic necrosis (IPN).

Results

Among 421 patients, 79 had diabetes at admission. Before PSM, diabetic patients had higher incidences of peripancreatic fluid (71% vs 47%, p<0.001) and IPN (48% vs 10%, p<0.001), higher surgical intervention rates (24% vs 12%, p=0.008), and significant differences in abdominocentesis (22% vs 11%, p=0.014). After PSM, 174 patients were matched, and the diabetes group still showed higher incidences of peripancreatic fluid (69% vs 47%, p=0.008), IPN (48% vs 11%, p<0.001), and surgical intervention rates (27% vs 13%, p=0.037). Diabetes, modified CT severity index (MCTSI), serum calcium, and HDL-c were identified as independent risk factors for IPN. The prediction model demonstrated good predictive value.

Conclusion

In MSAP and SAP patients, diabetes mellitus can exert an influence on their clinical outcome and is an independent risk factor for IPN. The alignment diagram and web calculator constructed on the basis of diabetes mellitus, modified CT severity index (MCTSI), serum calcium and high-density lipoprotein cholesterol (HDL-c) have good predictive value and clinical guidance for the occurrence of IPN in MSAP and SAP.

Risk Assessment for Gastrointestinal Diseases via Clinical Dimension and Genome-Wide Polygenic Risk Scores of Type 2 Diabetes: A Population-Based Cohort Study

OBJECTIVE

We aimed to evaluate whether individuals with type 2 diabetes (T2D) were at higher risk of developing a wide range of gastrointestinal diseases based on a population-based cohort study.

RESEARCH DESIGN AND METHODS

This study included 374,125 participants free of gastrointestinal disorders at baseline; of them, 19,719 (5.27%) with T2D were followed-up by linking to multiple medical records to record gastrointestinal disease diagnoses. Multivariable Cox models were used to estimate the hazard ratios (HRs) and CIs. Logistic models were used to examine the associations between polygenic risk scores (PRS) and clinical gastrointestinal phenotypes.

RESULTS

During a median follow-up of 12.0 years, we observed the new onset of 15 gastrointestinal diseases. Compared with nondiabetes, participants with T2D had an increased risk of gastritis and duodenitis (HR 1.58, 95% CI 1.51-1.65), peptic ulcer (HR 1.56, 95% CI 1.43-1.71), diverticular disease (HR 1.19, 95% CI 1.14-1.24), pancreatitis (HR 1.45, 95% CI 1.24-1.71), nonalcoholic fatty liver disease (HR 2.46, 95% CI 2.25-2.69), liver cirrhosis (HR 2.92, 95% CI 2.58-3.30), biliary disease (HR 1.18, 95% CI 1.10-1.26), gastrointestinal tract cancers (HR 1.28, 95% CI 1.17-1.40), and hepatobiliary and pancreatic cancer (HR 2.32, 95% CI 2.01-2.67). Positive associations of PRS of T2D with gastritis, duodenitis, and nonalcoholic fatty liver disease were also observed.

CONCLUSIONS

In this large cohort study, we found that T2D was associated with increased risks of a wide range of gastrointestinal outcomes. We suggest the importance of early detection and prevention of gastrointestinal disorders among patients with T2D.

Acute Pancreatitis and Type 2 Diabetes Mellitus: The Chicken-Egg Paradox-A Seven-Year Experience of a Large Tertiary Center

(1) Background: Preexisting type 2 diabetes mellitus (T2DM) has been shown in some studies as a risk factor and a severity factor for acute pancreatitis (AP). In this study, we aimed to demonstrate the link between T2DM and AP using data from a large retrospective epidemiological registry in a tertiary center. (2) Methods: We conducted a retrospective, large-cohort study of 1855 cases of AP and recurrent AP drawn from the seven-year consecutive hospitalization electronic health records of the largest acute-care tertiary teaching center in Romania. (3) Results: We observed a significant association between T2DM and a more severe course of the disease, and between T2DM and admission to the intensive care unit (ICU) due to AP, in our cohort using a chi-square test. However, we did not see a meaningful difference in comparing LoS-ICU between T2DM-AP and OAP (other known cause of AP). AP patients with T2DM had a greater probability of a severe course of the disease and were more likely to be admitted to the ICU than to the OAP. (4) Conclusions: The association between T2DM and AP remains a topic very representative of the "chicken-egg paradox". We need further research on DM-related AP and their bidirectional association as our study is limited by its retrospective design.

The development of new onset post-pancreatitis diabetes mellitus during hospitalisation is not associated with adverse outcomes

BACKGROUND

Patients with acute pancreatitis (AP) are at increased risk of developing post pancreatitis diabetes mellitus (PPDM). The aim of this study was to explore the incidence, risk factors and sequelae of developing PPDM in a UK tertiary referral centre.

METHODS

A prospectively collected single centre database was analysed. Patients were grouped according to whether they had DM or not. Patients with DM were further sub-grouped into pre-existing DM or PPDM. Outcomes measured included incidence of PPDM, mortality, ITU admission, overall length of stay (LOS) and local pancreatitis specific complications.

RESULTS

401 patients with AP between 2018 and 2021 were identified. Sixty-four (16%) of patients had pre-existing DM. Thirty-eight patients (11%) developed PPDM [mild (n = 4, 8.2%), moderate (n = 19, 10.1%), severe (n = 15, 15.2%), p = 0.326]. 71% required insulin therapy for the duration of follow-up or until death. The development of PPDM was strongly associated with the presence (p < 0.001) and extent of necrosis (p < 0.0001). On multi-variate analysis, the development of PPDM was not an independent predictor for increased LOS, ITU admission or overall mortality.

CONCLUSIONS

The incidence of PPDM was 11%. There was a strong correlation with extent of necrosis and the development of PPDM. PPDM did not adversely affect morbidity or mortality.

Association between time in range 70-180 mg/dl in early stage and severity with in patients acute pancreatitis

BACKGROUND

It is not well understood whether glucose control in the early stage of acute pancreatitis(AP) is related to outcome. This study aimed to investigate the association between blood glucose time in range (TIR) of 70-180 mg/dL in the first 72 h(h) on admission and the progression of AP.

METHODS

Individuals admitted with AP to the Gastroenterology Department of the Affiliated Changzhou No.2 People's Hospital of Nanjing Medical University between January 2017 and December 2021 were included and retrospectively evaluated. The percentage of TIR between 70 and 180 mg/dL in the first 72 h was calculated. According to the progress of AP at discharge, patients were divided into mild pancreatitis(MAP), and moderately severe acute pancreatitis (MSAP), or severe acute pancreatitis (SAP) groups. We examined the association between TIR or TIR ≥ 70% and AP severity using logistic regression models stratified by a glycosylated hemoglobin (HbA1c) level of 6.5%. Receiver operating characteristic (ROC) curves were generated to assess the ability of the TIR to predict MSAP or SAP.

RESULTS

A total of 298 individuals were included, of whom 35 developed MSAP or SAP. Logistic regression analyses indicated that TIR was independently associated with the incidence of more serious AP (odds ratio [OR] = 0.962, 95% CI = 0.941-0.983, p = 0.001). This association remained significant in individuals with HbA1c levels ≤ 6.5% (OR = 0.928, 95% CI = 0.888-0.969, p = 0.001). A TIR ≥ 70% was independently associated with reduced severity only in people with well-antecedent controls (OR = 0.238; 95% CI = 0.071-0.802; p = 0.020). TIR was not powerful enough to predict the severity of AP in both patients with poor antecedent glucose control (AUC = 0.641) or with HbA1c < 6.5% (AUC = 0.668).

CONCLUSIONS

TIR was independently associated with severity in patients with AP, particularly those with good antecedent glucose control.

The role of high serum triglyceride levels on pancreatic necrosis development and related complications

BACKGROUND

The relevance of elevated serum triglyceride (TG) levels in the early stages of acute pancreatitis (AP) not induced by hypertriglyceridemia (HTG) remains unclear. Our study aims to determine the role of elevated serum TG levels at admission in developing pancreatic necrosis.

METHODS

We analyzed the clinical data collected prospectively from patients with AP. According to TG levels measured in the first 24 h after admission, we stratified patients into four groups: Normal TG (< 150 mg/dL), Borderline-high TG (150-199 mg/dL), High TG (200-499 mg/dL) and Very high TG (≥ 500 mg/dL). We analyzed the association of TG levels and other risk factors with the development of pancreatic necrosis.

RESULTS

A total of 211 patients were included. In the Normal TG group: 122, in Borderline-high TG group: 38, in High TG group: 44, and in Very high TG group: 7. Pancreatic necrosis developed in 29.5% of the patients in the Normal TG group, 26.3% in the Borderline-high TG group, 52.3% in the High TG group, and 85.7% in the Very high TG group. The trend analysis observed a significant association between higher TG levels and pancreatic necrosis (p = 0.001). A multivariable analysis using logistic regression showed that elevated TG levels ≥ 200 mg/dL (High TG and Very high TG groups) were independently associated with pancreatic necrosis (OR: 3.27, 95% CI - 6.27, p < 0.001).

CONCLUSIONS

An elevated TG level at admission ≥ 200 mg/dl is independently associated with the development of pancreatic necrosis. The incidence of pancreatic necrosis increases proportionally with the severity of HTG.

Diabetes is an independent predictor of severe acute pancreatitis

OBJECTIVES

We aimed to determine the effect of diabetes mellitus (DM) on the severity of acute pancreatitis (AP) and whether diabetes is a predictor of severe acute pancreatitis (SAP).

METHODS

A total of 181 patients diagnosed with a first attack of AP in our hospital were retrospectively evaluated. AP severity was evaluated and compared between diabetic and non-diabetic patients. Independent factors predicting SAP were identified with a binary logistic regression model.

RESULTS

Of the 164 patients [108 (65.9%) women, 56 (34.1%) men] enrolled in the study, 35 patients (21.3%) had been diagnosed with DM, while 129 (78.7%) did not have DM. SAP, necrotizing pancreatitis, and local complications were observed to be more common among diabetic patients compared to non-diabetic patients (all P<0.001), while the incidences of systemic complications and transient or persistent organ failure were similar between the groups. The incidences of DM and cancer were higher in the SAP group (P<0.001 and P=0.033, respectively). The presence of DM (OR: 3.246, 95% CI: 1.278-8.244, P=0.013), high (≥3) Ranson score (OR: 3.529, 95% CI: 1.342-9.280, P=0.011), and high maximum C-reactive protein level (OR: 1.005, 95% CI: 1.001-1.010, P=0.046) were independent risk factors predicting SAP.

CONCLUSION

DM is both a risk factor for SAP and an independent predictor of SAP. Evaluation of the presence of DM at the time of diagnosis can help predict SAP in a considerably early phase.

Inhibition of Notch activity suppresses hyperglycemia-augmented polarization of macrophages to the M1 phenotype and alleviates acute pancreatitis

Acute pancreatitis (AP) is an acute inflammatory disorder characterized by acinar cell death and inflammation. Multiple factors cause hyperglycemia after AP. Macrophage polarization is involved in tissue injury and repair, and is regulated by Notch signaling during certain inflammatory diseases. The present study explores the relationship among hyperglycemia, macrophage polarization, and Notch signaling during AP and the related mechanisms. A cerulein-induced AP model was established in FVB/N mice, and AP with hyperglycemia was initiated by injection of 50% concentration glucose. Tissue damage, Notch activity, and macrophage polarization were assessed in pancreatic tissues. The role of Notch signaling in macrophage polarization during AP was also assessed in vitro by co-culturing primary macrophages and pancreatic acinar cells, and establishing a lipopolysaccharide (LPS)-induced inflammatory model in RAW264.7 cells. Pancreatic acinar cells were damaged and proinflammatory factor levels were increased in pancreatic tissues during AP. The hyperglycemic conditions aggravated pancreatic injury, increased macrophage infiltration, promoted macrophage polarization towards an M1 phenotype, and led to excessive up-regulation of Notch activity. Inhibition of Notch signaling by DAPT or Notch1 knockdown decreased the proportion of M1 macrophages and reduced the production of proinflammatory factors, thus mitigating pancreatic injury. These findings suggest that hyperglycemia induces excessive Notch signaling after AP and further aggravates AP by promoting pancreatic macrophage polarization towards the M1 phenotype. The Notch signaling pathway is a potential target for the prevention and treatment of AP.

Reduction in O-GlcNAcylation Mitigates the Severity of Inflammatory Response in Cerulein-Induced Acute Pancreatitis in a Mouse Model

Acute pancreatitis (AP) involves premature trypsinogen activation, which mediates a cascade of pro-inflammatory signaling that causes early stages of pancreatic injury. Activation of the transcription factor κB (NF-κB) and secretion of pro-inflammatory mediators are major events in AP. O-GlcNAc transferase (OGT), a stress-sensitive enzyme, was recently implicated to regulate NF-κB activation and inflammation in AP in vitro. This study aims to determine whether a pancreas-specific transgenic reduction in OGT in a mouse model affects the severity of AP in vivo. Mice with reduced pancreatic OGT (OGT^Panc+/-) at 8 weeks of age were randomized to cerulein, which induces pancreatitis, or saline injections. AP was confirmed by elevated amylase levels and on histological analysis. The histological scoring demonstrated that OGT^Panc+/- mice had decreased severity of AP. Additionally, serum lipase, LDH, and TNF-α in OGT^Panc+/- did not significantly increase in response to cerulein treatment as compared to controls, suggesting attenuated AP induction in this model. Our study reveals the effect of reducing pancreatic OGT levels on the severity of pancreatitis, warranting further investigation on the role of OGT in the pathology of AP.

The relationship between pre-existing diabetes mellitus and the severity of acute pancreatitis: Report from a large international registry

BACKGROUND/OBJECTIVES

The relationship between pre-existing diabetes mellitus (DM) and acute pancreatitis (AP) severity has not been established. We assessed the impact of pre-existing DM on AP severity in an international, prospectively ascertained registry.

METHODS

APPRENTICE registry prospectively enrolled 1543 AP patients from 22 centers across 4 continents (8 US, 6 Europe, 5 Latin America, 3 India) between 2015 and 2018, and collected detailed clinical information. Pre-existing DM was defined a diagnosis of DM prior to AP admission. The primary outcome was AP severity defined by the Revised Atlanta Classification (RAC). Secondary outcomes were development of systemic inflammatory response syndrome (SIRS) or intensive care unit (ICU) admission.

RESULTS

Pre-existing DM was present in 270 (17.5%) AP patients, of whom 252 (93.3%) had type 2 DM. Patients with pre-existing DM were significantly (p < 0.05) older (55.8 ± 16 vs. 48.3 ± 18.7 years), more likely to be overweight (BMI 29.5 ± 7 vs. 27.2 ± 6.2), have hypertriglyceridemia as the etiology (15% vs. 2%) and prior AP (33 vs. 24%). Mild, moderate, and severe AP were noted in 66%, 23%, and 11% of patients, respectively. On multivariable analysis, pre-existing DM did not significantly impact AP severity assessed by the RAC (moderate-severe vs. mild AP, OR = 0.86, 95% CI 0.63-1.18; severe vs. mild-moderate AP, OR = 1.05, 95% CI, 0.67-1.63), development of SIRS, or the need for ICU admission. No interaction was noted between DM status and continent.

CONCLUSION

About one in 5 patients with AP have pre-existing DM. Once confounding risk factors are considered, pre-existing DM per se is not a risk factor for severe AP.

Analysis of Pain and Analgesia Protocols in Acute Cerulein-Induced Pancreatitis in Male C57BL/6 Mice

Pancreatitis is known to be painful in humans and companion animals. However, the extent of pain in experimental mouse models of acute pancreatitis is unknown. Consequently, the severity classification of acute pancreatitis in mice is controversially discussed and standardized pain management is missing. In this study, we investigated acute Cerulein-induced pancreatitis with pain-specific and well-being orientated parameters to detect its impact on mice. Male C57BL/6J male mice were injected with Cerulein; animals that received saline injections served as control group. The animals were observed for weight change and water intake. To assess pain, behaviors like stretch-and-press and reduced rearing, the Mouse Grimace Scale, and von Frey hypersensitivity were assessed. Fecal corticosterone metabolites and burrowing behavior were assessed to detect changes in the animal’s well-being. Pancreatitis severity was evaluated with amylase and lipase in the blood and pancreas histology. To investigate whether different analgesics can alleviate signs of pain, and if they influence pancreas inflammation, animals received Buprenorphine, Paracetamol in combination with Tramadol, or Metamizole in the drinking water. The calculated intake of these analgesics via drinking reached values stated to be efficient for pain alleviation. While pancreatitis did not seem to be painful, we detected acute pain from Cerulein injections that could not be alleviated by analgesics. The number of inflammatory cells in the pancreas did not differ with the analgesic administered. In conclusion: (1) Cerulein injections appear to be acutely painful but pain could not be alleviated by the tested analgesics, (2) acute pancreatitis induced by our protocol did not induce obvious signs of pain, (3) analgesic substances had no detectable influence on inflammation. Nevertheless, protocols inducing more severe or even chronic pancreatitis might evoke more pain and analgesic treatment might become imperative. Considering our results, we recommend the use of Buprenorphine via drinking water in these protocols. Further studies to search for efficient analgesics that can alleviate the acute pain induced by Cerulein injections are needed.

Prognostic Value of Glucose-to-Lymphocyte Ratio in Critically Ill Patients with Acute Pancreatitis

Background

Glucose metabolism and systemic inflammation have been associated with prognosis in acute pancreatitis (AP) patients. However, the possible value as a prognostic marker of the glucose-to-lymphocyte ratio (GLR) has not been evaluated in critically ill patients with AP.

Methods

This study included 1,133 critically ill patients with AP from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database, who were randomly divided into the training cohort (n=806) and the validation cohort (n=327) at a ratio of 7:3. X-tile software was used to determine the optimal cut-off values for GLR. Area under the curve (AUC) analysis was performed to compare the performance between GLR and other blood-based inflammatory biomarkers. Univariate and multivariate Cox regression analyses were applied to select prognostic factors associated with in-hospital mortality. A nomogram model was developed based on the identified prognostic factors and the validation cohort was used to further validate the nomogram.

Results

The optimal cut-off value for GLR was 0.9. The ROC analyses showed that the discrimination abilities of GLR were better than other blood-based inflammatory biomarkers. Multivariate Cox regression analysis demonstrated that age, platelet, albumin, bilirubin, Sequential Organ Failure Assessment (SOFA) score, and GLR are independent predictors of poor overall survival in the training cohort and were incorporated into the nomogram for in-hospital mortality as independent factors. The nomogram exhibited better discrimination with C-indexes in the training cohort and the validation cohort of 0.886 (95% CI=0.849–0.922) and 0.841 (95% CI=0.767–0.915), respectively. The calibration plot revealed an adequate fit of the nomogram for predicting the risk of in-hospital mortality in both sets.

Conclusion

As an easily available biomarker, GLR can independently predict the in-hospital mortality of critically ill patients with AP. The nomogram combining GLR with other significant features exerted favorable predictive performance for in-hospital mortality.

Chronic Pancreatitis and the Development of Pancreatic Cancer

Pancreatitis is a fibro-inflammatory disorder of the pancreas that can occur acutely or chronically as a result of the activation of digestive enzymes that damage pancreatic cells, which promotes inflammation. Chronic pancreatitis with persistent fibro-inflammation of the pancreas progresses to pancreatic cancer, which is the fourth leading cause of cancer deaths across the globe. Pancreatic cancer involves cross-talk of inflammatory, proliferative, migratory, and fibrotic mechanisms. In this review, we discuss the role of cytokines in the inflammatory cell storm in pancreatitis and pancreatic cancer and their role in the activation of SDF1α/CXCR4, SOCS3, inflammasome, and NF-κB signaling. The aberrant immune reactions contribute to pathological damage of acinar and ductal cells, and the activation of pancreatic stellate cells to a myofibroblast-like phenotype. We summarize several aspects involved in the promotion of pancreatic cancer by inflammation and include a number of regulatory molecules that inhibit that process.

Insulin protects acinar cells during pancreatitis by preserving glycolytic ATP supply to calcium pumps

Acute pancreatitis (AP) is serious inflammatory disease of the pancreas. Accumulating evidence links diabetes with severity of AP, suggesting that endogenous insulin may be protective. We investigated this putative protective effect of insulin during cellular and in vivo models of AP in diabetic mice (Ins2^Akita) and Pancreatic Acinar cell-specific Conditional Insulin Receptor Knock Out mice (PACIRKO). Caerulein and palmitoleic acid (POA)/ethanol-induced pancreatitis was more severe in both Ins2^Akita and PACIRKO vs control mice, suggesting that endogenous insulin directly protects acinar cells in vivo. In isolated pancreatic acinar cells, insulin induced Akt-mediated phosphorylation of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2 (PFKFB2) which upregulated glycolysis thereby preventing POA-induced ATP depletion, inhibition of the ATP-dependent plasma membrane Ca²⁺ ATPase (PMCA) and cytotoxic Ca²⁺ overload. These data provide the first mechanistic link between diabetes and severity of AP and suggest that phosphorylation of PFKFB2 may represent a potential therapeutic strategy for treatment of AP.

Fibroblast growth factor 21: a novel long-acting hypoglycemic drug for canine diabetes

Currently, insulin is commonly used in the clinical management of canine diabetes. However, it must be injected preprandially causing much inconvenience to the owners. Therefore, the development of long-acting hypoglycemic agents has attracted much attention in the scientific community. This study aimed to investigate the long-acting hypoglycemic effect of canine fibroblast growth factor 21 (cFGF-21) in diabetic dogs. Diabetic dogs were administered with cFGF-21, polyethylene glycol-modified cFGF-21 (PEG-cFGF-21), or insulin once a day, once every 2, 3, or 4 days subcutaneously. The results showed that cFGF-21 and PEG-cFGF-21 maintained blood glucose comparable to normal levels for 2 and 3 days respectively while insulin maintained the blood glucose for only 2 h after a single injection. After treatment with cFGF-21, oral glucose tolerance test (OGTT) was significantly improved with glycosylated hemoglobin (HbA1c) close to the normal levels. In addition, cFGF-21 significantly repaired islet β cells, increased insulin content, and protected the pancreas from streptozotocin-induced injury. Furthermore, cFGF-21 exhibited both antioxidant and anti-inflammatory properties in the pancreas. We conclude, therefore, that cFGF-21 and PEG-cFGF-21 can maintain blood glucose comparable to normal levels for 2 and 3 days respectively after a single dose. The long-acting efficacy of cFGF-21 can be attributed to improvement in oxidative stress and the reduction of inflammation in the pancreas.

MicroRNAs as systemic biomarkers to assess distress in animal models for gastrointestinal diseases

Severity assessment of animal experiments is mainly conducted by using subjective parameters. A widely applicable biomarker to assess animal distress could contribute to an objective severity assessment in different animal models. Here, the distress of three murine animal models for gastrointestinal diseases was assessed by multiple behavioral and physiological parameters. To identify possible new biomarkers for distress 750 highly conserved microRNAs were measured in the blood plasma of mice before and after the induction of pancreatitis. Deregulated miRNA candidates were identified and further quantified in additional animal models for pancreatic cancer and cholestasis. MiR-375 and miR-203 were upregulated during pancreatitis and down regulated during cholestasis, whereas miR-132 was upregulated in all models. Correlation between miR-132 and plasma corticosterone concentrations resulted in the highest correlation coefficient, when compared to the analysis of miR-375, miR-203 and miR-30b. These results indicate that miR-132 might function as a general biomarker for distress, whereas the other miRNAs were altered in a disease specific manner. In conclusion, plasma miRNA profiling may help to better characterize the level of distress in mouse models for gastrointestinal diseases.

Serine administration as a novel prophylactic approach to reduce the severity of acute pancreatitis during diabetes in mice

AIMS/HYPOTHESIS

Compared with the general population, individuals with diabetes have a higher risk of developing severe acute pancreatitis, a highly debilitating and potentially lethal inflammation of the exocrine pancreas. In this study, we investigated whether 1-deoxysphingolipids, atypical lipids that increase in the circulation following the development of diabetes, exacerbate the severity of pancreatitis in a diabetic setting.

METHODS

We analysed whether administration of an L-serine-enriched diet to mouse models of diabetes, an established method for decreasing the synthesis of 1-deoxysphingolipids in vivo, reduced the severity of acute pancreatitis. Furthermore, we elucidated the molecular mechanisms underlying the lipotoxicity exerted by 1-deoxysphingolipids towards rodent pancreatic acinar cells in vitro.

RESULTS

We demonstrated that L-serine supplementation reduced the damage of acinar tissue resulting from the induction of pancreatitis in diabetic mice (average histological damage score: 1.5 in L-serine-treated mice vs 2.7 in the control group). At the cellular level, we showed that L-serine decreased the production of reactive oxygen species, endoplasmic reticulum stress and cellular apoptosis in acinar tissue. Importantly, these parameters, together with DNA damage, were triggered in acinar cells upon treatment with 1-deoxysphingolipids in vitro, suggesting that these lipids are cytotoxic towards pancreatic acinar cells in a cell-autonomous manner. In search of the initiating events of the observed cytotoxicity, we discovered that 1-deoxysphingolipids induced early mitochondrial dysfunction in acinar cells, characterised by ultrastructural alterations, impaired oxygen consumption rate and reduced ATP synthesis.

CONCLUSIONS/INTERPRETATION

Our results suggest that 1-deoxysphingolipids directly damage the functionality of pancreatic acinar cells and highlight that an L-serine-enriched diet may be used as a promising prophylactic intervention to reduce the severity of pancreatitis in the context of diabetes.

Diabetes mellitus and the risk of pancreatitis: A systematic review and meta-analysis of cohort studies

BACKGROUND

Diabetes mellitus has been associated with increased risk of pancreatitis in several studies, however, not all studies have found an association. We conducted a systematic review and meta-analysis of prospective studies on diabetes mellitus and pancreatitis to clarify the association.

METHODS

PubMed and Embase databases were searched for studies on diabetes mellitus and pancreatitis up to 8^th of January 2020. Cohort studies that reported adjusted relative risk (RR) estimates and 95% confidence intervals (CIs) for the association between diabetes diagnosis and pancreatitis were included and summary RRs (95% CIs) were calculated using a random effects model.

RESULTS

Eight cohort studies were included in the meta-analysis, and seven of these were included in the analysis of diabetes mellitus and acute pancreatitis (14124 cases, 5.7 million participants). Comparing diabetes patients with persons without diabetes the summary RRs (95% CIs) were 1.74 (95% CI: 1.33-2.29, I² = 95%) for acute pancreatitis, 1.40 (95% CI: 0.88-2.22, I² = 0%, n = 2) for chronic pancreatitis, and 1.39 (95% CI: 1.07-1.80, I² = 54%, n = 3) for pancreatitis overall. Although there was some indication of publication bias in the analysis of acute pancreatitis this appeared to be explained by one outlying study which when excluded did not substantially alter the association. The results persisted in several subgroup and sensitivity analyses.

CONCLUSIONS

These results suggest that diabetes patients are at an increased risk of acute pancreatitis. Further studies are needed on diabetes and risk of chronic pancreatitis, pancreatitis overall and on gallstone-related and non-gallstone-related pancreatitis.

Preexisting Diabetes Elevates Risk of Local and Systemic Complications in Acute Pancreatitis: Systematic Review and Meta-analysis

The prevalence of diabetes mellitus (DM) and acute pancreatitis (AP) increases continuously, therefore, to understand the effects of preexisting diabetes on AP is crucially needed. Here, we performed a systematic review and meta-analysis in which AP patients including DM and non-DM groups were sorted. Several outcome parameters were analyzed, and the odds ratio (OR) and standardized mean difference with 95% confidence intervals (CIs) were calculated.We found 1417 articles, of which 9 articles involving 354,880 patients were analyzed. More complications were seen in diabetic patients than in non-DM patients (OR, 1.553 [95% CI, 1.266-1.904]; P < 0.001). Intensive care unit admission (OR, 1.799 [95% CI, 1.442-2.243]; P < 0.001) and renal failure (OR, 1.585 [95% CI, 1.278-1.966]; P < 0.001) were more frequent in DM patients. There was a tendency of higher mortality and local complications (OR, 1.276 [95% CI, 0.991-1.643]; P = 0.059; and OR, 1.267 [95% CI, 0.964-1.659]; P = 0.090, respectively) in preexisting DM. Length of hospitalization was longer in DM patients (standardized mean difference, 0.217 [95% CI, 0.075-0.360]; P = 0.003). Preexisting DM negatively influences the outcome of AP and increases the risk of renal failure, local complications, and mortality.

Impact of hyperglycemia on autoimmune pancreatitis and regulatory T-cells

AIM

To evaluate the influence of hyperglycemia on the progression of autoimmune pancreatitis.

METHODS

We induced hyperglycemia by repetitive intraperitoneal (ip) injection of 50 mg/kg streptozotocin in MRL/MpJ mice, which develop autoimmune pancreatitis due to a genetic predisposition. We compared the extent of inflammation (histological score, CD3+ lymphocytes, CD8+ T-cells, CD4+ T-cells, Foxp3+ T-helper cells) in the pancreas of hyperglycemic and normoglycemic mice. We also analyzed the number of leukocytes, lymphocytes, granulocytes and monocytes in the blood. In addition, we determined the percentage of CD3+ lymphocytes, CD8+ T-cells, CD4+ T-cells, Foxp3+ T-helper cells, Foxp3+ CD25+ T-helper and Foxp3- T-helper cells in the spleen by flow cytometry.

RESULTS

Treatment with streptozotocin caused a strong induction of hyperglycemia and a reduction in body weight (P < 0.001). Severe hyperglycemia did not, however, lead to an aggravation, but rather to a slight attenuation of autoimmune pancreatitis. In the pancreas, both the histological score of the pancreas as well as the number of CD3+ lymphocytes (P < 0.053) were decreased by hyperglycemia. No major changes in the percentage of CD8+ T-cells, CD4+ T-cells, Foxp3+ T-helper cells were observed between hyperglycemic and normoglycemic mice. Hyperglycemia increased the numbers of leukocytes (P < 0.001), lymphocytes (P = 0.016), granulocytes and monocytes (P = 0.001) in the blood. Hyperglycemia also moderately reduced the percentage of CD3+ lymphocytes (P = 0.057), significantly increased the percentage of Foxp3+ T-helper cells (P = 0.018) and Foxp3+ CD25+ T-helper cells (P = 0.021) and reduced the percentage of Foxp3- T-helper cells (P = 0.034) in the spleen.

CONCLUSION

Hyperglycemia does not aggravate but moderately attenuates autoimmune pancreatitis, possibly by increasing the percentage of regulatory T-cells in the spleen.

Chronic Pancreatitis in the 21st Century - Research Challenges and Opportunities: Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop

A workshop was sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases to focus on research gaps and opportunities in chronic pancreatitis (CP) and its sequelae. This conference marked the 20th year anniversary of the discovery of the cationic trypsinogen (PRSS1) gene mutation for hereditary pancreatitis. The event was held on July 27, 2016, and structured into 4 sessions: (1) pathophysiology, (2) exocrine complications, (3) endocrine complications, and (4) pain. The current state of knowledge was reviewed; many knowledge gaps and research needs were identified that require further investigation. Common themes included the need to design better tools to diagnose CP and its sequelae early and reliably, identify predisposing risk factors for disease progression, develop standardized protocols to distinguish type 3c diabetes mellitus from other types of diabetes, and design effective therapeutic strategies through novel cell culture technologies, animal models mimicking human disease, and pain management tools. Gene therapy and cystic fibrosis conductance regulator potentiators as possible treatments of CP were discussed. Importantly, the need for CP end points and intermediate targets for future drug trials was emphasized.

The influence of exendin-4 intervention on -obese diabetic mouse blood and the pancreatic tissue immune microenvironment

The aim of the study was to determine the influence of exendin-4 intervention on non-obese diabetic (NOD) mouse blood and the pancreatic tissue immune microenvironment. A total of 40 clean NOD mice were used in the study and randomly divided into 4 groups (n=10/group). The first group was blank control group D with normal saline intervention, and with different doses of exendin, i.e.,-4 2, 4 and 8 µg/kg/day. The three remaining groups were: i) Low-dose group A; ii) medium-dose group B; and iii) high-dose group C. Mice in the four groups went through intervention for 8 weeks. Their mass and blood glucose levels were tested each week. After 8 weeks, the mice were sacrificed, and mouse serum samples were reserved. The ELISA method was used to test peripheral blood (PB), IL-2, IFN-γ and IL-10 levels. Pancreatic samples were created. Immunohistochemistry was used to observe the infiltration degree of mouse pancreatitis and the local expression state of pancreatic IL-10. Mouse pancreatic tissues were suspended in pancreatic cell suspension. Flow cytometry was used to test the state of T-cell subsets CD4 and CD25. Mouse pancreatitis in control group D was mainly at grade 2and 3. Under a light microscope, it was observed that pancreatic cell morphology was in disorder, and the size and quantity of the pancreas was small. Mouse pancreatitis in the exendin-4 low-dose group A, medium-dose group B and high-dose group C was mainly at grade 0 and 1. Under a light microscope, it was observed that pancreatic cell morphology improved, the infiltration degree of lymphocyte was improved and pancreatic islet size was restored somewhat. Additionally, a few brownish granules were identified within the pancreatic sample cells in control group D. There were many brownish granules with deep color within the pancreatic sample cells in exendin-4 low-dose group A, medium-dose group B and high-dose group C. IL-10 immunohistochemistry scores in the low-dose group A, medium-dose group B and high-dose group C were 3.82±0.72, 4.34±0.86 and 4.81±0.94, respectively, and were higher than the score of 2.25±0.63 in control group D. CD4+CD25+T-cell proportions in mouse pancreatic tissues of low-dose group A, medium-dose group B and high-dose group C were 5.31, 5.53 and 5.74%, respectively, which were higher than that of the CD4+CD25+T-cell proportion (1.62% in control group D). The CD4+CD25^high T-cell proportion in CD4+T-cells in group A, B and C increased. Compared with control group D, serum IL-10 levels in the exendin-4 low-dose group A, medium-dose group B and high-dose group C increased (P<0.05), while levels of IL-2 and IFN-γ decreased (P<0.05). Additionally, the difference of serum IL-10, IL-2 and IFN-γ levels in the low-dose group A, medium-dose group B and high-dose group C was of statistical significance (P<0.05). Exendin-4 intervention can increase quantities of CD4 and CD8+T cells in NOD mouse pancreases, with PB IL-10 expression and local expression of IL-10 in pancreatic tissues. It also can inhibit the expression of serum IL-2 and IFN-γ, regulate the organism immune microenvironment and prevent diabetes. CD4+CD25^high T cells increase in NOD tumor infiltration lymphocytes mediated by exendin-4 intervention, which may be related to the fact that exendin-4 inhibits the lethal effect of CD8+T cells through contact among cells and eventually exerts immunosuppressive effect.

Diabetes increases pancreatic fibrosis during chronic inflammation

Diabetes and fibrosis can be concurrent processes in several diseases such as cystic fibrosis or chronic pancreatitis. To evaluate whether diabetes can influence fibrosis and thus aggravate the pathological process, the progression of chronic pancreatitis was assessed in diabetic and non diabetic mice. For this purpose, insulin producing beta-cells in C57Bl/6J mice were selectively impaired by administration of streptozotocin. Chronic pancreatitis was then induced by repetitive administration of cerulein in normoglycaemic and hyperglycaemic mice. Diabetes caused enhanced collagen I deposition within three weeks of the onset of chronic pancreatitis and increased the proliferation of interstitial cells. This was accompanied by an increased number of interlobular fibroblasts, which expressed S100A4 (fibroblast-specific protein-1) and stimulation of α-smooth muscle actin expression of pancreatic stellate cells. In addition, the observed aggravation of chronic pancreatitis by diabetes also led to a significantly enhanced atrophy of the pancreas, increased infiltration of inflammatory chloracetate esterase positive cells and enhanced acinar cell death. We conclude that diabetes has a detrimental influence on the progression of chronic pancreatitis by aggravating fibrosis, inflammation and pancreatic atrophy.

Diabetes increases pancreatitis induced systemic inflammation but has little effect on inflammation and cell death in the lung

Acute pancreatitis (AP) can lead to a systemic inflammatory response that often results in acute lung injury and single or multiple organ failure. In a previous study we demonstrated that diabetes aggravates the local pathophysiological process during AP. In this study we explore, if diabetes also increases pancreatitis induced systemic inflammation and causes lung injury. Acute pancreatitis was induced in untreated and streptozotocin-treated diabetic mice by injection of cerulein. Systemic inflammation was studied by IL-6 ELISA in blood plasma and white blood cell count. Lung inflammation and lung injury were quantified by chloroacetate esterase staining, evaluation of the alveolar cellularity index and cleaved caspase-3 immunohistochemistry. In normoglycaemic mice AP increased the IL-6 concentration in plasma and caused lymphocytopenia. Diabetes significantly increased the IL-6 concentration in plasma and further reduced the number of lymphocytes during AP, whereas diabetes had little effect on these parameters in the absence of pancreatitis. However, diabetes only marginally increased lung inflammation and did not lead to cell death of the lung epithelium during AP. We conclude that diabetes increases parameters of systemic inflammation during AP, but that this increase is insufficient to cause lung injury.

Insulin protects pancreatic acinar cells from palmitoleic acid-induced cellular injury

Acute pancreatitis is a serious and sometimes fatal inflammatory disease where the pancreas digests itself. The non-oxidative ethanol metabolites palmitoleic acid (POA) and POA-ethylester (POAEE) are reported to induce pancreatitis caused by impaired mitochondrial metabolism, cytosolic Ca²⁺ ([Ca²⁺]_i) overload and necrosis of pancreatic acinar cells. Metabolism and [Ca²⁺]_i are linked critically by the ATP-driven plasma membrane Ca²⁺-ATPase (PMCA) important for maintaining low resting [Ca²⁺]_i. The aim of the current study was to test the protective effects of insulin on cellular injury induced by the pancreatitis-inducing agents, ethanol, POA, and POAEE. Rat pancreatic acinar cells were isolated by collagenase digestion and [Ca²⁺]_i was measured by fura-2 imaging. An in situ [Ca²⁺]_i clearance assay was used to assess PMCA activity. Magnesium green (MgGreen) and a luciferase-based ATP kit were used to assess cellular ATP depletion. Ethanol (100 mm) and POAEE (100 μm) induced a small but irreversible Ca²⁺ overload response but had no significant effect on PMCA activity. POA (50–100 μm) induced a robust Ca²⁺ overload, ATP depletion, inhibited PMCA activity, and consequently induced necrosis. Insulin pretreatment (100 nm for 30 min) prevented the POA-induced Ca²⁺ overload, ATP depletion, inhibition of the PMCA, and necrosis. Moreover, the insulin-mediated protection of the POA-induced Ca²⁺ overload was partially prevented by the phosphoinositide-3-kinase (PI3K) inhibitor, LY294002. These data provide the first evidence that insulin directly protects pancreatic acinar cell injury induced by bona fide pancreatitis-inducing agents, such as POA. This may have important therapeutic implications for the treatment of pancreatitis.

Risk of development of acute pancreatitis with pre-existing diabetes: a meta-analysis

OBJECTIVES

It is well established that acute pancreatitis (AP) often causes diabetes mellitus. However, whether pre-existing diabetes is associated with the development of AP remains unknown. To clarify the association of pre-existing diabetes and the development of AP, we carried out a meta-analysis of observational studies.

METHODS

A computerized literature search was performed in MEDLINE (from 1 January 1966) and EMBASE (from 1 January 1974), through 31 January 2012. We also searched the reference lists of relevant articles. Summary relative risks with their corresponding 95% confidence intervals (CIs) were calculated using a random-effects model. Between-study heterogeneity was assessed using Cochran's Q statistic and the I 2.

RESULTS

A total of seven articles (10 523 incident cases of AP) were included in this meta-analysis. Analysis of seven studies indicated that, compared with nondiabetic individuals, diabetic individuals had a 92% increased risk of development of AP (95% CI 1.50-2.47). There was significant evidence of heterogeneity among these studies (P heterogeneity<0.001, I 2=93.0%). These increased risks were independent of alcohol use, gallstones, and hyperlipidemia.

CONCLUSION

Although the current evidence supports a positive link between pre-existing diabetes and an increased risk of development of AP, additional studies, with a perfect design, are required before definitive conclusions can be drawn.