Assessment of oxidative stress in chronic pancreatitis patients

Circulating Biomarkers Involved in the Development of and Progression to Chronic Pancreatitis-A Literature Review

Chronic pancreatitis (CP) is the end-stage of continuous inflammation and fibrosis in the pancreas evolving from acute- to recurrent acute-, early, and, finally, end-stage CP. Currently, prevention is the only way to reduce disease burden. In this setting, early detection is of great importance. Due to the anatomy and risks associated with direct sampling from pancreatic tissue, most of our information on the human pancreas arises from circulating biomarkers thought to be involved in pancreatic pathophysiology or injury. The present review provides the status of circulating biomarkers involved in the development of and progression to CP.

Efficacy and Predictors of Pain Response to Combined Antioxidants in Children with Chronic Pancreatitis

BACKGROUND

Pain is a major problem in 90% of patients with chronic pancreatitis (CP). Studies evaluating response to antioxidants (AO) are conflicting and no pediatric studies are available.

AIMS

To evaluate markers of oxidative stress (OS), and efficacy and predictors of response to AO in improving pain in children with CP.

METHODS

Antioxidants were given to CP children for 6 months. Subjects were assessed at baseline and post-therapy for pain and markers of OS [serum thiobarbituric acid reactive substances (TBARS), superoxide dismutase (S-SOD)] and antioxidant levels [vitamin C, selenium, total antioxidant capacity-ferric reducing ability of plasma (FRAP)]. Matched healthy controls were assessed for OS and antioxidant levels. Good response was defined as ≥ 50% reduction in number of painful days/month.

RESULTS

48 CP children (25 boys, age 13 years) and 14 controls were enrolled. 38/48 cases completed 6 months of therapy. CP cases had higher OS [TBARS (7.8 vs 5.2 nmol/mL; p < 0.001)] and lower antioxidant levels [FRAP (231 vs. 381.3 µmol/L; p = 0.003), vitamin C (0.646 vs. 0.780 mg/dL; p < 0.001)] than controls. Significant reduction in TBARS and S-SOD and increase in FRAP, vitamin C, and selenium occurred after 6 months. 10.5% cases had minor side effects. 26(68%) cases had a good response, with 9(24%) becoming pain-free. Subjects with severe ductal changes had lower median BMI (- 0.73 vs 0.10; p = 0.04) and responded less often than those with mild changes (17/29 vs 9/9; p = 0.036).

CONCLUSION

CP children have higher OS than healthy controls. Antioxidant therapy is safe. Pain response is seen in 68% cases, less often in patients with severe ductal changes.

New insights into the etiology, risk factors, and pathogenesis of pancreatitis in dogs: Potential impacts on clinical practice

While most cases of pancreatitis in dogs are thought to be idiopathic, potential risk factors are identified. In this article we provide a state‐of‐the‐art overview of suspected risk factors for pancreatitis in dogs, allowing for improved awareness and detection of potential dog‐specific risk factors, which might guide the development of disease prevention strategies. Additionally, we review important advances in our understanding of the pathophysiology of pancreatitis and potential areas for therapeutic manipulation based thereof. The outcome of pathophysiologic mechanisms and the development of clinical disease is dependent on the balance between stressors and protective mechanisms, which can be evaluated using the critical threshold theory.

Differential expressions of miR-223, miR-424, miR-145, miR-200c, miR-139 in experimental rat chronic pancreatitis model and their relationship between oxidative stress, endoplasmic reticulum stress, and apoptosis

OBJECTIVES

This study aimed to research the roles of miR-139, miR-221, miR-200c, miR-145, miR-223, miR-424, and miR-377 in endoplasmic reticulum stress (ERS), oxidative stress (OS), fibrosis, and apoptosis processes in chronic pancreatitis (CP) rat model.

MATERIALS AND METHODS

Fourteen rats were randomized into 2 groups (Group 1, sham group (n=7) and Group 2, CP group (n=7)). TGF-beta and malondialdehyde concentrations were measured in rat blood samples. qRT-PCR was used to investigate the expression levels of 7 miRNAs in the pancreas tissues. The correlations of mRNA undergoing significant changes with inflammation (TNF-α, IL-6), ERS (Ire1-α, Perk), apoptosis (Caspase 3, Bcl-2), OS (Cat, Gpx1), and fibrosis (α-Sma) were investigated .

RESULTS

The biochemical results and histopathological scores in Group 1 were statistically significantly high compared with Group 2 (P<0.5). Expression levels of seven miRNAs (miR-200c, miR-145, miR-223, miR-424) were significantly higher, while miR-139 was significantly lower in CP. In our study, we found that miR-200c, miR-145, and miR-139 may contribute to CP progression and cellular processes based on the correlation between ERS, OS, apoptosis, and inflammation with miRNA expression levels.

CONCLUSION

miR-200c, miR-145, miR-139, miR-223, and miR-424 play roles in the CP model. They may be used as candidate biomarkers for the CP process.

Antioxidants for Pancreatic Functions in Chronic Pancreatitis: A Double-blind Randomized Placebo-controlled Pilot Study

BACKGROUND

Antioxidants (AO) supplementation in chronic pancreatitis (CP) has been evaluated for pain. But it is not clear whether AO in CP have an effect on pancreatic functions and other clinical outcomes. We evaluated effect of AO on endocrine function in CP.

MATERIALS AND METHODS

Double-blind placebo (PL)-controlled randomized pilot study on 107 patients with CP assigned to receive daily combined AO or PL for 6 months. Primary outcome was: improvement in endocrine function (Homeostasis Model Assessment-Insulin Resistance). Secondary outcome measures were: improvement in C-peptide, Qualitative Insulin Sensitivity Check Index, exocrine pancreatic function (fecal elastase), surrogate markers of fibrosis (platelet-derived growth factor BB, transforming growth factor-β1, α-smooth muscle actin), quality of life (QOL), pain, nutritional status, markers of oxidative stress (OS), AO status, and inflammation.

RESULTS

There was an increase in levels of serum selenium (107.2±26.9 to 109.7±26.9 vs. 104.1±28.6 to 124.0±33.6 μg/L, P=0.022) and serum vitamin E [0.58 (range, 0.27-3.22) to 0.66 (range, 0.34-1.98) vs. 0.63 (range, 0.28-1.73) to 1.09 (range, 0.25-2.91) mg/dL, P=0.001] in the AO than the PL group. However, no significant differences were observed between groups in any of the primary or secondary outcome measures.

CONCLUSIONS

Supplementation with AO to patients with CP causes a sustained increase in blood levels of AO; however, it has no addition benefit over PL on endocrine and exocrine functions, markers of fibrosis, OS and inflammation, nutritional status, pain and QOL. Further larger studies with adequate sample size are required.

Current trends in pharmacological approaches for treatment and management of acute pancreatitis – a review

Objectives

Acute pancreatitis (AP) is an inimical disorder associated with overall mortality rates between 10-15%. It is a disorder of the exocrine pancreas which is characterized by local and systemic inflammatory responses primarily driven by oxidative stress and death of pancreatic acinar cells. The severity of AP ranges from mild pancreatic edema with complete recuperative possibilities to serious systemic inflammatory response resulting in peripancreatic/pancreatic necrosis, multiple organ failure, and death.

Key findings

We have retrieved the potential alternative approaches that are developed lately for efficacious treatment of AP from the currently available literature and recently reported experimental studies. This review summarizes the need for alternative approaches and combinatorial treatment strategies to deal with AP based on literature search using specific key words in PubMed and ScienceDirect databases.

Summary

Since AP results from perturbations of multiple signaling pathways, the so called “monotargeted smart drugs” of the past decade is highly unlikely to be effective. Also, the conventional treatment approaches were mainly involved in providing palliative care instead of curing the disease. Hence, many researchers are beginning to focus on developing alternate therapies to treat AP effectively. This review also summarizes the recent trends in the combinatorial approaches available for AP treatment.

Asparaginase-Associated Pancreatitis in Acute Lymphoblastic Leukemia: Results From the NOPHO ALL2008 Treatment of Patients 1-45 Years of Age

PURPOSE

Asparaginase-associated pancreatitis (AAP) is common in patients with acute lymphoblastic leukemia (ALL), but risk differences across age groups both in relation to first-time AAP and after asparaginase re-exposure have not been explored.

PATIENTS AND METHODS

We prospectively registered AAP (n = 168) during treatment of 2,448 consecutive ALL patients aged 1.0-45.9 years diagnosed from July 2008 to October 2018 and treated according to the Nordic Society of Pediatric Hematology and Oncology (NOPHO) ALL2008 protocol.

RESULTS

Compared with patients aged 1.0-9.9 years, adjusted AAP hazard ratios (HRa) were associated with higher age with almost identical HRa (1.6; 95% CI, 1.1 to 2.3; P = .02) for adolescents (10.0-17.9 years) and adults (18.0-45.9 years). The day 280 cumulative incidences of AAP were 7.0% for children (1.0-9.9 years: 95% CI, 5.4 to 8.6), 10.1% for adolescents (10.0 to 17.9 years: 95% CI, 7.0 to 13.3), and 11.0% for adults (18.0-45.9 years: 95% CI, 7.1 to 14.9; P = .03). Adolescents had increased odds of both acute (odds ratio [OR], 5.2; 95% CI, 2.1 to 13.2; P = .0005) and persisting complications (OR, 6.7; 95% CI, 2.4 to 18.4; P = .0002) compared with children (1.0-9.9 years), whereas adults had increased odds of only persisting complications (OR, 4.1; 95% CI, 1.4 to 11.8; P = .01). Fifteen of 34 asparaginase-rechallenged patients developed a second AAP. Asparaginase was truncated in 17/21 patients with AAP who subsequently developed leukemic relapse, but neither AAP nor the asparaginase truncation was associated with increased risk of relapse.

CONCLUSION

Older children and adults had similar AAP risk, whereas morbidity was most pronounced among adolescents. Asparaginase re-exposure should be considered only for patients with an anticipated high risk of leukemic relapse, because multiple studies strongly indicate that reduction of asparaginase treatment intensity increases the risk of relapse.

Common variants in glyoxalase I do not increase chronic pancreatitis risk

Introduction

Chronic pancreatitis (CP) may be caused by oxidative stress. An important source of reactive oxygen species (ROS) is the methylglyoxal-derived formation of advanced glycation endproducts (AGE). Methylglyoxal is detoxified by Glyoxalase I (GLO1). A reduction in GLO1 activity results in increased ROS. Single nucleotide polymorphisms (SNPs) of GLO1 have been linked to various inflammatory diseases. Here, we analyzed whether common GLO1 variants are associated with alcoholic (ACP) and non-alcoholic CP (NACP).

Methods

Using melting curve analysis, we genotyped a screening cohort of 223 ACP, 218 NACP patients, and 328 controls for 11 tagging SNPs defined by the SNPinfo LD TAG SNP Selection tool and the functionally relevant variant rs4746. For selected variants the cohorts were extended to up to 1,441 patient samples.

Results

In the ACP cohort, comparison of genotypes for rs1937780 between patients and controls displayed an ambiguous result in the screening cohort (p = 0.08). However, in the extended cohort of 1,441 patients no statistically significant association was found for the comparison of genotypes (p = 0.11), nor in logistic regression analysis (p = 0.214, OR 1.072, 95% CI 0.961–1.196). In the NACP screening cohort SNPs rs937662, rs1699012, and rs4746 displayed an ambiguous result when patients were compared to controls in the recessive or dominant model (p = 0.08, 0.08, and 0.07, respectively). Again, these associations were not confirmed in the extended cohorts (rs937662, dominant model: p = 0.07, logistic regression: p = 0.07, OR 1.207, 95% CI 0.985–1.480) or in the replication cohorts for rs4746 (Germany, p = 0.42, OR 1.080, 95% CI 0.673–1.124; France, p = 0.19, OR 0.90, 95% CI 0.76–1.06; China, p = 0.24, OR 1.18, 95% CI 0.90–1.54) and rs1699012 (Germany, Munich; p = 0.279, OR 0.903, 95% CI 0.750–1.087).

Conclusions

Common GLO1 variants do not increase chronic pancreatitis risk.

Nutrition and Inflammatory Biomarkers in Chronic Pancreatitis Patients

BACKGROUND

Chronic pancreatitis (CP) patients frequently experience malabsorption and maldigestion, leading to micronutrient and macronutrient deficiencies. Comorbid diabetes and lifestyle habits, such as alcohol consumption, may impact nutrition status.

METHODS

We compared micronutrient antioxidant, bone metabolism, serum protein, and inflammatory marker levels in 301 CP patients and 266 controls with no known pancreatic disease. We analyzed serum prealbumin and retinol binding protein; vitamins A, D, E, and B12; osteocalcin; tumor necrosis factor-α; and C-reactive protein (CRP). We also evaluated biomarkers among subsets of patients, examining factors including time since diagnosis, body mass index, alcohol as primary etiology, diabetes mellitus, vitamin supplementation, and pancreatic enzyme replacement.

RESULTS

After correcting for multiple comparisons, CP patients had significantly lower levels than controls of the following: vitamin A (40.9 vs 45.4 μg/dL) and vitamin E (α-tocopherol [8.7 vs 10.3 mg/L] and γ-tocopherol [1.8 vs 2.2 mg/L]), as well as osteocalcin (7.9 vs 10 ng/mL) and serum prealbumin (23 vs 27 mg/dL). Both patients and controls who took vitamin supplements had higher serum levels of vitamins than those not taking supplements. Compared with controls, in controlled analyses, CP patients had significantly lower levels of vitamins A, D, and E (both α-tocopherol and γ-tocopherol). CP patients also had significantly lower levels of osteocalcin, serum prealbumin, and retinol binding protein, and higher CRP.

CONCLUSIONS

CP patients demonstrated lower levels of selected nutrition and bone metabolism biomarkers than controls. Diabetes and alcohol did not impact biomarkers. Vitamin supplements and pancreatic enzyme replacement therapy improved nutrition biomarkers in CP patients.

Genetic Variants in the Manganese Superoxide Dismutase 2 Gene and in the Catalase Gene are not Associated With Alcoholic Chronic Pancreatitis

Aims

Oxidative stress may contribute to the development of chronic pancreatitis (CP). The enzymes manganese superoxide dismutase 2 (MnSOD, SOD2) and catalase (CAT) counteract free radical activity within the mitochondria and the cytosol. Moreover, CAT activity contributes to the transformation of ethanol to acetaldehyde, a toxic intermediate product of ethanol metabolism, which has been associated with pancreatic damage. Common functional polymorphisms have been described in the MnSOD gene [rs4880, NM_000636.3:c.47 T > C, alanine (ALA) to valine (Val)] and in the CAT promoter region [rs1001179, NG_013339.1:g.4760 C > T]. We investigated whether these polymorphisms are associated with alcoholic CP.

Methods

We genotyped 470 patients with alcoholic CP for these MnSOD and CAT polymorphisms. We also analysed these variants in 357 healthy control subjects, and in an additional control group of 113 individuals with non-alcoholic CP. We used the age at onset of CP as marker of disease severity and investigated whether different genotypes are associated with different ages at onset. In patients with alcoholic CP, we investigated whether an interaction exists between smoking behaviour and genotypes by comparing genotype distributions in smokers and non-smokers.

Results

We did not observe significant differences of genotype frequencies between patient groups and controls. In patient groups, we did not find significant differences in the ages at onset between different genotypes. We did not observe an interaction between these polymorphisms. We did not find an association of these variants with smoking behaviour.

Conclusions

The investigated MnSOD and CAT polymorphisms do not predispose to the development of alcoholic CP.

Short summary

Patients with alcoholic pancreatitis and controls were genotyped for polymorphisms in oxidative stress genes. There were no significant differences of genotype frequencies between patients and controls, and no association with the age at onset of disease was observed. The polymorphisms are not associated with the development of alcoholic pancreatitis.

Inflammation-Related Pancreatic Carcinogenesis: Mechanisms and Clinical Potentials in Advances

Chronic inflammation has long been considered critical in pancreatic carcinogenesis, and recently studies showed that some anti-inflammatory agents such as aspirin could potentially be used to attenuate pancreatic carcinogenesis. Several inflammation-related critical transcription factors and pathways such as NF-κB (nuclear factor κ-light-chain enhancer of activated B cells) and reactive oxygen species have been confirmed to be involved in carcinogenesis. However, its underlying mechanisms are far from clear, which largely limits further development of potential anticarcinogenesis drugs. As a result, it is of great importance for us to better understand and gain a better perspective in inflammation-related pancreatic carcinogenesis. In this review, we systematically analyzed recent advances concerning inflammation-related pancreatic carcinogenesis and brought out the possible underlying mechanisms. Potential preventive and therapeutic strategies based on anti-inflammatory agents have also been further discussed.

Ca2+ signalling underlying pancreatitis

In spite of significant scientific progress in recent years, acute pancreatitis (AP) is still a dangerous and in up to 5% of cases deadly disease with no specific cure. It is self-resolved in the majority of cases, but could result in chronic pancreatitis (CP) and increased risk of pancreatic cancer (PC). One of the early events in AP is premature activation of digestive pro-enzymes, including trypsinogen, inside pancreatic acinar cells (PACs) due to an excessive rise in the cytosolic Ca²⁺ concentration, which is the result of Ca²⁺ release from internal stores followed by Ca²⁺ entry through the store operated Ca²⁺ channels in the plasma membrane. The leading causes of AP are high alcohol intake and biliary disease with gallstones obstruction leading to bile reflux into the pancreatic duct. Recently attention in this area of research turned to another cause of AP - Asparaginase based drugs - which have been used quite successfully in treatments of childhood acute lymphoblastic leukaemia (ALL). Unfortunately, Asparaginase is implicated in triggering AP in 5-10% of cases as a side effect of the anti-cancer therapy. The main features of Asparaginase-elicited AP (AAP) were found to be remarkably similar to AP induced by alcohol metabolites and bile acids. Several potential therapeutic avenues in counteracting AAP have been suggested and could also be useful for dealing with AP induced by other causes. Another interesting development in this field includes recent research related to pancreatic stellate cells (PSCs) that are much less studied in their natural environment but nevertheless critically involved in AP, CP and PC. This review will attempt to evaluate developments, approaches and potential therapies for AP and discuss links to other relevant diseases.

Analytical validation of an automated assay for ferric-reducing ability of plasma in dog serum

We performed analytical validation of an automated ferric-reducing ability of plasma (FRAP) assay in the serum of dogs. Intra- and interassay precision, accuracy, detection limit, and effects of hemolysis and lipemia were evaluated. Intra- and interassay coefficients of variation were <1% and <13%, respectively. The assay showed a high correlation with a FRAP assay described previously, and results were linear when serial sample dilutions were tested. The detection limit was lower than the values observed in sera from healthy dogs; decreased serum FRAP was found in dogs with leishmaniosis. Lipemia and hemolysis caused a significant increase in the results of the assay.

Gastrointestinal complications associated with anorexia nervosa: A systematic review

OBJECTIVE

A systematic review identifying gastrointestinal (GI) complications attributable to anorexia nervosa (AN) was completed.

METHOD

Studies of any design exploring the pathogenesis of complications and treatment strategies were included. The review was completed in accordance with PRISMA standards.

RESULTS

A total of 123 articles were retained, including one randomized control trial. The majority of included studies were case reports and case series. Controlled studies demonstrated that patients with AN were more likely to have delays in gastric motility, gastric emptying and intestinal transit than comparator groups although results were not uniform across all studies. Published reports suggest that complications can occur at any segment of the GI tract. These issues may derive as a consequence of severe malnourishment, from eating disorder related symptoms such as self-induced purging or from the refeeding process itself. Multiple studies noted that patients with AN report high rates of GI symptoms although in the few cases where medical testing was undertaken, correlations between self-reported symptoms and measurable pathology were not demonstrated.

DISCUSSION

GI complications may occur throughout the entire GI tract in patients with AN. It is recommended that clinicians use careful judgment when pursuing targeted investigation or introducing symptom specific treatments in response to GI complaints. Evidence suggests that most GI complications resolve with refeeding and cessation of ED symptoms.

Novel lipophilic probe for detecting near-membrane reactive oxygen species responses and its application for studies of pancreatic acinar cells: effects of pyocyanin and L-ornithine

AIMS

The aim of this study was to develop a fluorescent reactive oxygen species (ROS) probe, which is preferentially localized in cellular membranes and displays a strong change in fluorescence upon oxidation. We also aimed to test the performance of this probe for detecting pathophysiologically relevant ROS responses in isolated cells.

RESULTS

We introduced a novel lipophilic ROS probe dihydrorhodamine B octadecyl ester (H2RB-C18). We then applied the new probe to characterize the ROS changes triggered by inducers of acute pancreatitis in pancreatic acinar cells. We resolved ROS changes produced by L-ornithine, L-arginine, cholecystokinin-8, acetylcholine, taurolithocholic acid 3-sulfate, palmitoleic acid ethyl ester, and the bacterial toxin pyocyanin. Particularly prominent ROS responses were induced by pyocyanin and L-ornithine. These ROS responses were accompanied by changes in cytosolic Ca(2+)concentration ([Ca(2+)]i), mitochondrial membrane potential (ΔΨ), and NAD(P)H concentration.

INNOVATION

The study describes a novel sensitive lipophilic ROS probe. The probe is particularly suitable for detecting ROS in near-membrane regions and therefore for reporting the ROS environment of plasma membrane channels and pumps.

CONCLUSIONS

In our experimental conditions, the novel probe was more sensitive than 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein (CM-H2DCF) and dihydrorhodamine123 (H2R123) and allowed us to resolve ROS responses to secretagogues, pyocyanin, and L-ornithine. Changes in the fluorescence of the new probe were particularly prominent in the peripheral plasma membrane-associated regions. Our findings suggest that the new probe will be a useful tool in studies of the contribution of ROS to the pathophysiology of exocrine pancreas and other organs/tissues.

Role of methionine containing antioxidant combination in the management of pain in chronic pancreatitis: a systematic review and meta-analysis

BACKGROUND

Pain in CP results from inflammation and neuroimmune alterations that are associated with oxidative stress, among other mechanisms. This is marked by depletion of antioxidant defenses including methionine, which is a donor of methyl moieties that maintains the acinar transsulfuration pathway. We performed a systematic review and meta-analysis of trials evaluating methionine-containing antioxidants in CP.

PATIENT AND METHODS

Literature search was conducted in Medline/Pubmed, EMBASE, and Cochrane databases. Systematic review and meta-analysis was performed per PRISMA guidelines. Main study outcome was pain relief. GRADE system was used for quality assessment. Heterogeneity was assessed by the Q and I(2) measures; publication bias by Egger's test. Random-effect model (DerSimonian and Laird) was used if there was heterogeneity.

RESULTS

Eight studies (n = 411) were identified that used methionine-containing antioxidants. The study duration ranged from 10 wks to 12 months. All studies used methionine, organic selenium, ascorbate, beta-carotene and alpha-tocoferol. Four studies (including two RCTs) that reported change in pain scores were metaanalyzed. Though overall effect [standardized difference in means (95% CI)] on pain score reduction was -0.95 (-1.738 to -0.160) (z = -2.36; p = 0.018), the significance was lost when the two RCTs were meta-analyzed. RCTs that reported the number of pain free patients had a statistically significant overall effect of -3.204 (p = 0.001). Though more patients on methionine containing antioxidants had adverse events, majority of them were mild.

CONCLUSION

Methionine containing antioxidants appear to result in pain reduction in a significant proportion of CP patients. Further randomized controlled trials with homogeneous outcome measures are needed.

Impact of oxidative stress on the cytoskeleton of pancreatic epithelial cells

In the present study the effect of reactive oxygen species on the morphological changes of pancreatic epithelial cells in a three-dimensional culture system was investigated. In addition, the expression of signaling molecules during this process was determined. Matrigel™ was used to construct a three-dimensional culture model of pancreatic epithelial and cancer cells. The cultured cells were stimulated with 1 or 200 μmol/l H₂O₂ (a typical reactive oxygen species), and the morphological changes were then evaluated after 15 min, 1 h and 4 h. The cytoskeleton of the cells was observed using laser scanning confocal microscopy with immunofluorescence staining. In addition, the nuclear content of nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) was detected using ELISA. The results demonstrated that treatment with 200 μmol/l H₂O₂ induced cell contraction after 15 min, and cell morphology recovered after 1 h; however, cell size was reduced after 4 h. Consequently, intracellular actin and microtubules were rapidly lost following H₂O₂ treatment, and the cytoskeleton became indistinct and eventually disintegrated after 4 h. Similar observations were noted for the normal pancreatic epithelial and cancer cells. By contrast, treatment with 1 μmol/l H₂O₂ did not affect the morphology and cytoskeleton of pancreatic epithelial cells. In addition, 200 μmol/l H₂O₂ treatment increased the activity of NF-κB gradually, while 1 μmol/l H₂O₂ treatment was found to have little impact on the activity of NF-κB. Therefore, it was demonstrated that oxidative stress can induce the early onset of reversible cell contraction and cytoskeleton depolarization in pancreatic epithelial cells, and can increase NF-κB expression.

An overview of the diagnosis and management of nutrition in chronic pancreatitis

Chronic pancreatitis is characterized by long-standing inflammation of the pancreas, which results in fibrosis and the gradual loss of pancreatic function. The loss of islets and acinar cells results in diabetes and exocrine insufficiency, respectively. Exocrine insufficiency can result in maldigestion of fat, protein, and carbohydrate as well as vitamins and minerals. Patients may present with variable severity of disease, from mild to severe. The diagnosis of chronic pancreatitis can be challenging, especially in patients with early or mild disease who have few to no morphologic abnormalities on standard abdominal imaging studies. A number of imaging modalities and tests have evolved to aid in the diagnosis of chronic pancreatitis based on changes in structure or function. Clinicians typically focus on treating pain in chronic pancreatitis as opposed to exocrine insufficiency, despite the fact that maldigestion and malabsorption can result in nutrition deficiencies. The aims of this review are to describe the various modalities used to diagnose chronic pancreatitis, to illustrate the nutrition deficiencies associated with exocrine insufficiency, and to provide an overview of nutrition assessment and treatment in these patients.

Age-dependent effects of UCP2 deficiency on experimental acute pancreatitis in mice

Reactive oxygen species (ROS) have been implicated in the pathogenesis of acute pancreatitis (AP) for many years but experimental evidence is still limited. Uncoupling protein 2 (UCP2)-deficient mice are an accepted model of age-related oxidative stress. Here, we have analysed how UCP2 deficiency affects the severity of experimental AP in young and older mice (3 and 12 months old, respectively) triggered by up to 7 injections of the secretagogue cerulein (50 μg/kg body weight) at hourly intervals. Disease severity was assessed at time points from 3 hours to 7 days based on pancreatic histopathology, serum levels of alpha-amylase, intrapancreatic trypsin activation and levels of myeloperoxidase (MPO) in lung and pancreatic tissue. Furthermore, in vitro studies with pancreatic acini were performed. At an age of 3 months, UCP2^-/- mice and wild-type (WT) C57BL/6 mice were virtually indistinguishable with respect to disease severity. In contrast, 12 months old UCP2^-/- mice developed a more severe pancreatic damage than WT mice at late time points after the induction of AP (24 h and 7 days, respectively), suggesting retarded regeneration. Furthermore, a higher peak level of alpha-amylase activity and gradually increased MPO levels in pancreatic and lung tissue were observed in UCP2^-/- mice. Interestingly, intrapancreatic trypsin activities (in vivo studies) and intraacinar trypsin and elastase activation in response to cerulein treatment (in vitro studies) were not enhanced but even diminished in the knockout strain. Finally, UCP2^-/- mice displayed a diminished ratio of reduced and oxidized glutathione in serum but no increased ROS levels in pancreatic acini. Together, our data indicate an aggravating effect of UCP2 deficiency on the severity of experimental AP in older but not in young mice. We suggest that increased severity of AP in 12 months old UCP2^-/- is caused by an imbalanced inflammatory response but is unrelated to acinar cell functions.

Contribution of environment and genetics to pancreatic cancer susceptibility

Several risk factors have been identified as potential contributors to pancreatic cancer development, including environmental and lifestyle factors, such as smoking, drinking and diet, and medical conditions such as diabetes and pancreatitis, all of which generate oxidative stress and DNA damage. Oxidative stress status can be modified by environmental factors and also by an individual's unique genetic makeup. Here we examined the contribution of environment and genetics to an individual's level of oxidative stress, DNA damage and susceptibility to pancreatic cancer in a pilot study using three groups of subjects: a newly diagnosed pancreatic cancer group, a healthy genetically-unrelated control group living with the case subject, and a healthy genetically-related control group which does not reside with the subject. Oxidative stress and DNA damage was evaluated by measuring total antioxidant capacity, direct and oxidative DNA damage by Comet assay, and malondialdehyde levels. Direct DNA damage was significantly elevated in pancreatic cancer patients (age and sex adjusted mean ± standard error: 1.00 ± 0.05) versus both healthy unrelated and related controls (0.70 ± 0.06, p<0.001 and 0.82 ± 0.07, p = 0.046, respectively). Analysis of 22 selected SNPs in oxidative stress and DNA damage genes revealed that CYP2A6 L160H was associated with pancreatic cancer. In addition, DNA damage was found to be associated with TNFA -308G>A and ERCC4 R415Q polymorphisms. These results suggest that measurement of DNA damage, as well as select SNPs, may provide an important screening tool to identify individuals at risk for development of pancreatic cancer.

Decreased serum paraoxonase activity in patients with chronic pancreatitis

BACKGROUND

Recent evidences suggest that oxidative stress is involved in the mechanism of chronic pancreatitis (CP). Paraoxonase 1 (PON1) plays an important role as an endogenous free-radical scavenging molecule. The aim of our study is to investigate whether serum PON1 activity is associated with the presence of CP.

METHODS

A total of 186 patients with alcoholic CP and 132 healthy subjects were enrolled in this study. Serum PON1 activity was measured using paraoxon as a substrate.

RESULTS

Serum PON1 activity was significantly decreased in CP patients compared with healthy subjects. Multivariable logistic regression analysis revealed that serum PON1 activity was a determinant of the presence of CP (OR = 0.992, 95% CI = 0.987-0.998; P = 0.006).

CONCLUSIONS

Decreased serum PON1 activity may be considered as a predicting marker of the presence of CP.

Antioxidant status and oxidative stress markers in pancreatic cancer and chronic pancreatitis

OBJECTIVES

Oxidative stress has been implicated in the pathogenesis of chronic pancreatitis (CP) and pancreatic cancer (PC). The study aim was to assess the oxidative stress markers and antioxidant defense system in patients with CP and those with PC.

METHODS

Activities of superoxide dismutase 1 (SOD1), catalase (CAT), glutathione peroxidase 1 (GPX1), glutathione reductase (GR), arylesterase (PON1-A) and lactonase (PON1-L) activities of paraoxonase 1 (PON1) and concentrations of reduced glutathione, conjugated dienes in low-density lipoprotein (CD/LDL) and oxidized LDL (ox-LDL/LDL) were assessed in 50 PC and 50 CP patients and 50 age and sex-matched controls.

RESULTS

Comparison of PC and CP groups to controls found the following changes: glutathione peroxidase 1 (GPX1) (-20.2%, -25.5%; P < 0.001), glutathione reductase (GR) (-9.5%, -11.9%; P < 0.05), SOD1 (+22.9%; P < 0.01), CAT (-10.6%; P < 0.05), PON1-A (-34.3%, -16.0%; P < 0.001), PON1-L (-44.2%; -17.0%; P < 0.01), conjugated dienes in LDL (CD/LDL) (+20%, +33.3%; P < 0.05) and ox-LDL/LDL (+42.2%, +14.4%; P < 0.05). The patients with PC had changed activities and levels of SOD1 (+24.2%), CAT (-10.4); P < 0.01), PON1-A (-21.7%), PON1-L (-32.9%), and ox-LDL/LDL (+24.3%); (all P < 0.01) compared with the patients with CP.

CONCLUSIONS

Reduced antioxidant defense system capacity and increased markers of oxidative stress were found in PC and CP. PON1-L and CAT activities, along with ox-LDL/LDL levels, were the independent factors differentiating the patients with PC from the patients with CP.

Effect of antioxidant supplementation on surrogate markers of fibrosis in chronic pancreatitis: a randomized, placebo-controlled trial

OBJECTIVES

This study aimed to determine the effect of antioxidant (AO) supplementation on surrogate markers of fibrosis in patients with chronic pancreatitis (CP).

METHODS

In a randomized, placebo (PL)-controlled trial, patients with CP were randomized to groups that were given PL or AO for 3 months. Outcome measures were change in serum levels of transforming growth factor β1 and platelet-derived growth factor AA (PDGF-AA) (primary outcome) as well as blood markers of oxidative stress (thiobarbituric acid-reactive substances) and AO status (ferric-reducing ability of plasma) (secondary outcome). Pain relief and analgesic requirement was also recorded.

RESULTS

Patients (n = 61; mean [SD] age, 35.2 [10.0]; male patients, 43) were assigned to AO (n = 31) and PL (n = 30) groups. The median (range) percent reduction from baseline to 3 months in levels of PDGF-AA (17.1% [-25.3% to 88.7%] vs 2.8% [-243.1% to 30.2%]; P = 0.001), transforming growth factor β1 (P = 0.573), and thiobarbituric acid-reactive substances (P = 0.207) as well as percent increment from baseline to 3 months in ferric-reducing ability of plasma (P = 0.003) were higher in the AO group compared with the PL group. Proportion of patients who had both reduced PDGF-AA and reduced pain was greater in AO as compared with PL group (17/31 vs 9/30, P = 0.05)

CONCLUSIONS

Reduction in markers of fibrosis (PDGF-AA) translated into clinical outcome (reduction in pain and analgesic requirements) in those supplemented with AOs in CP (trial registration, CTRI/2011/05/001747).

Intake patterns of food nutrients and other substances associated with chronic pancreatitis

BACKGROUND/OBJECTIVES

While alcohol is considered the most common aetiological factor for chronic pancreatitis, the intake of various nutrient and other substances is thought to act as cofactors in the pathogenesis of the disease due to modulation of oxidative stress. This study examined incident cases of acute pancreatitis to determine the dietary and other intakes that characterize those harbouring underlying chronic pancreatitis.

METHODS

Cases of acute pancreatitis presenting to a single institution were prospectively recruited (n = 153). The presence of chronic pancreatitis was defined by a composite of clinical, biochemical and radiological criteria. Information was obtained on the intake of dietary macro- and micronutrients, coffee, tobacco and alcohol in the period just prior to the acute exacerbation. Univariate and multivariate analyses of association were undertaken. Principal components analysis (PCA) was employed to elicit patterns of intake.

RESULTS

After adjustment for key demographic variables, no individual nutrient or other substance showed a significant association with chronic pancreatitis. However, following PCA there emerged a significant positive association with a so-called "stimulant" intake pattern and a negative association with a so-called "nutritive" pattern.

CONCLUSIONS

Preceding an acute exacerbation, patients with underlying chronic pancreatitis are more likely to substitute food-based intake for combinations of other substances, such as tobacco and coffee. This finding may have application in the clinical setting as part of a chronic disease management protocol.

The effect of smoking on expression of IL-6 and antioxidants in pancreatic fluids and tissues in patients with chronic pancreatitis

OBJECTIVES

The present study was conducted to ascertain whether cigarette smoke induces oxidative stress in the human pancreas concurrently with inflammation.

MATERIALS AND METHODS

The influence of tobacco smoking on the serum level of interleukin-6 (IL-6), on the activities of glutathione peroxidase (GPx) and copper-zinc superoxide dismutase (Cu/Zn SOD) as well as on the metallothionein (MT) level in the pancreatic pseudocyst fluid and its immunohistochemical localization in tissues of non-smoking (n = 9) and smoking (n = 12) patients with diagnosed chronic pancreatitis (CP) was measured. The concentration of interleukin-6 and metallothionein was determined by means of ELISA and the radioisotopic method, respectively. The enzyme activities in the fluid were assayed by the colorimetric method. Samples of tissues of normal pancreas (n = 4) and CP (non-smoking n = 7; smoking n = 12) were verified histopathologically and then IL-6, MT and enzymes were localized by immunohistochemical staining using the monoclonal anti-human antibody.

RESULTS

The concentrations of metallothionein and interleukin-6 were significantly higher in smoking patients with CP (as compared with the non-smoking population (p < 0.01; p < 0.001). Interestingly, the ratio of MT/IL-6 in smoking patients with CP was reduced in comparison to non-smoking patients (respectively: 1.1; 5.6). In smoking patients, a significant elevation of the Cu/Zn SOD and GPx activities was revealed as compared with the non-smokers (p < 0.04; p < 0.0007). These studies clearly demonstrate a moderate and strong expression of IL-6 and enzymes in acinar, islet and duct cells of smoking patients.

CONCLUSIONS

These observations favor the role of the oxidative stress in the induction of pancreatitis associated with chronic cigarette smoke inhalation.

Lipidomic profiling of serum and pancreatic fluid in chronic pancreatitis

OBJECTIVES

Oxidative stress is intimately involved in the pathogenesis of chronic pancreatitis (CP), and its quantification may represent a useful biomarker. The aim was to determine whether oxidized fatty acid (OxFA) levels in serum and/or pancreatic fluid are elevated in CP.

METHODS

Patients evaluated for abdominal pain were classified into 3 groups (controls, mild CP, and severe CP). Serum and secretin-stimulated pancreatic fluid samples were stored under conditions to minimize artificial oxidation. Ten arachidonic and linoleic acid oxidation products were simultaneously measured using liquid chromatography-electrospray ionization-tandem mass spectrometry.

RESULTS

Most OxFAs were significantly elevated in the serum of patients with mild and severe CP compared to controls and correlated with structural features on endoscopic ultrasound. For example, the mean (SD) ratio of serum 13-HODE to its precursor linoleic acid was 0.03 (0.004) in controls, 0.06 (0.02) in mild CP, and 0.10 (0.04) in severe CP (analysis of variance, P = 0.004) and had a strong correlation with endoscopic ultrasound features (Spearman r = 0.84, P < 0.001). In the pancreatic fluid, statistically significant increases of OxFA products were observed in mild CP compared to controls.

CONCLUSIONS

Oxidized fatty acid products are increased in the serum and pancreatic fluid of patients with CP, suggesting a potential role as biomarkers.

ABBREVIATIONS

AA - arachidonic acidANOVA - analysis of varianceAP - acute pancreatitisCP - chronic pancreatitisePFT - endoscopic pancreatic function testEUS - endoscopic ultrasoundHPLC - high-pressure liquid chromatographyHETE - hydroxy-eicosatetranoic acidHODE - hydroxy-octadecadienoic acidLA - linoleic acidLC-ESI-MS/MS - liquid chromatography-electrospray ionization-tandem mass spectrometryM - molarOxFA - oxidized fatty acidsPFT - pancreatic function test.

Antioxidants and chronic pancreatitis: theory of oxidative stress and trials of antioxidant therapy

Chronic pancreatitis (CP) is an inflammatory disease characterized by the progressive destruction of pancreatic tissue and resulting in pancreatic exocrine and endocrine insufficiency. Increased oxidative stress has been implicated as a potential mechanism in its etiology and pathology. A number of studies have demonstrated that CP patients have a compromised antioxidant status, which may be a contributing factor to the enhanced oxidative state associated with the disease. Nutrition is an essential consideration in the treatment of CP, especially since diet is a source of several antioxidants and cofactors required for the production of cellular antioxidant enzymes. Many CP patients have an inadequate intake of macro and micronutrients because of abdominal pain and discomfort, which often increase postprandially and discourage eating. Exocrine insufficiency leads to further complications by preventing adequate digestion and absorption of ingested food, thus causing even greater deficiencies and impairment of antioxidant status. The aims of this article are to review the oxidative stress model of CP and to examine the evidence for nutrition, and, particularly, antioxidants, in the treatment of CP.

Modern treatment of patients with chronic pancreatitis

CP remains a challenging disease. Endoscopic and surgical management, along with antioxidants, have helped in reducing chronic pain. Management of exocrine and endocrine insufficiency forms the cornerstone for improving nutrition in these patients. Newer therapeutic targets that will transcend the management of CP beyond just pain control and enzyme supplementation are required in the future.

Reactive oxygen species induced by bile acid induce apoptosis and protect against necrosis in pancreatic acinar cells

BACKGROUND & AIMS

Oxidative stress is implicated in the pathogenesis of pancreatitis, but clinical trials of antioxidants have produced conflicting results. We examined the role of intracellular reactive oxygen species (ROS) in pancreatic acinar cell injury.

METHODS

Freshly isolated murine and human pancreatic acinar cells were studied using confocal microscopy to measure changes in intracellular and mitochondrial ROS concentrations ([ROS]I and [ROS]M), cytosolic and mitochondrial calcium concentrations ([Ca2+]C and [Ca2+]M), reduced nicotinamide adenine dinucleotide phosphate levels, and death pathways in response to taurolithocholate acid sulfate (TLC-S) or the oxidant menadione. Ca2+-activated Cl- currents were measured using whole-cell patch clamp, with or without adenosine triphosphate (ATP).

RESULTS

TLC-S induced prolonged increases in [Ca2+]C and [Ca2+]M, which led to dose-dependent increases in [ROS]I and [ROS]M, impaired production of ATP, apoptosis, and necrosis. Inhibition of the antioxidant reduced nicotinamide adenine dinucleotide phosphate quinine oxidoreductase by 2,4-dimethoxy-2-methylnaphthalene potentiated the increases in [ROS]I and apoptosis but reduced necrosis, whereas the antioxidant N-acetyl-L-cysteine reduced [ROS]I and apoptosis but increased necrosis. Inhibition of mitochondrial ROS production prevented apoptosis but did not alter necrosis; autophagy had no detectable role. Patched ATP prevented sustained increases in [Ca2+]C and necrosis.

CONCLUSIONS

Increases in [ROS]M and [ROS]I during bile acid injury of pancreatic acinar cells promote apoptosis but not necrosis. These results indicate that alternative strategies to antioxidants are required for oxidative stress in acute pancreatitis.

Insights into the development of alcoholic chronic pancreatitis at Soweto, South Africa: a controlled cross-sectional study

OBJECTIVE

We asked why so few working-class Africans of Soweto have chronic pancreatitis (CP) when alcoholism is the norm.

METHODS

Twenty-one alcoholics with acute psychosis but normal pancreas were investigated for lifestyle, micronutrient status, electrophilic stress, and iron overload.

RESULTS

Alcoholics consumed more ethanol daily than did 14 previously studied patients with CP (P = 0.003); cigarette usage was similar; both groups had even poorer vitamin C status than 14 healthy controls, and no participant had iron overload. The CP group had higher scores for exposure to occupational xenobiotics than did alcoholics (P < 0.05), with lower plasma glutathione (P = 0.047) and urinary inorganic sulfate (P = 0.009). Further analysis identified hyperhomocysteinemia in the alcoholic set, with lower vitamin B12 (P < 0.001), higher folic acid (P = 0.003), and similar vitamin B6 levels compared with controls.

CONCLUSIONS

The transition from alcoholism to CP in Soweto is associated with occupational exposure to xenobiotics. Among detoxification systems that are strained thereby, glutathione and inorganic sulfate depend on methionine intake, which is ample in Sowetans, whereas vitamin C, which exerts a glutathione-sparing effect, is deficient. Hence, a daily tablet of vitamin C may enable community prophylaxis against the disease--but homocysteine status would need monitoring.

Assessment of oxidative status in chronic pancreatitis and its relation with zinc status

BACKGROUND

Oxidative stress-induced free radicals have been implicated in the pathology of chronic pancreatitis (CP).

AIM

We aimed to estimate oxidative stress and antioxidant status in tropical chronic pancreatitis (TCP) and alcoholic chronic pancreatitis (ACP) and correlate with zinc status.

METHODS

One hundred and seventy-five CP patients (91 TCP, 84 ACP) and 113 healthy subjects were prospectively studied. Disease characteristics and imaging features were recorded. Erythrocyte reduced glutathione, glutathione peroxidase (GPx), superoxide dismutase (SOD), plasma vitamin C, and erythrocyte thiobarbituric acid reactive substance (TBARS) were estimated by spectrophotometry. Erythrocyte zinc was estimated by flame atomic absorption spectrophotometry.

RESULTS

Enhanced lipid peroxidation with concomitant decrease in antioxidant status was observed in both TCP and ACP patients (p < 0.05). The findings were comparable in both diabetic and non-diabetic CP patients. Significantly, lower plasma vitamin C and elevated levels of erythrocyte TBARS was noted in TCP as compared to ACP patients. The erythrocyte zinc significantly correlated with SOD activity (r = 0.450, p < 0.001).

CONCLUSIONS

Our study corroborates the role of oxidative stress in CP and suggests some differences in oxidative status in TCP and ACP patients. Zinc deficiency appears to affect oxidative status in CP patients.

Chronic pancreatitis

PURPOSE OF REVIEW

We review important new clinical observations in chronic pancreatitis made in the last year.

RECENT FINDINGS

Cholecystokinin-stimulated endoscopic pancreatic function testing has low specificity for diagnosis of early chronic pancreatitis, likely because of correctable technical limitations or failure to exclude confounding diseases. Fecal elastase 1 is a poor test for diagnosing pancreatic malabsorption. A 2-week trial of corticosteroids may differentiate autoimmune pancreatitis (AIP) from pancreatic cancer in select patients. A genetic screen may help to predict relapse of AIP. Repeated, 6-month visits to counsel against alcohol use may reduce recurrent attacks of alcoholic pancreatitis. A five-component antioxidant cocktail may reduce the frequency of pain in chronic pancreatitis by 1.5 days per month.

SUMMARY

Researchers this last year have further characterized clinical aspects of chronic pancreatitis that may lead to improved detection of early chronic pancreatitis and AIP, risk stratification and application of risk-lowering strategies to prevent relapses in AIP or the development of recurrent (and possibly chronic) alcoholic pancreatitis and new evidence that antioxidants may have a modest effect on reducing the dominant symptom in chronic pancreatitis, abdominal pain.

A randomized controlled trial of antioxidant supplementation for pain relief in patients with chronic pancreatitis

BACKGROUND & AIMS

Oxidative stress has been implicated in the pathophysiology of chronic pancreatitis (CP). We evaluated the effects of antioxidant supplementation on pain relief, oxidative stress, and antioxidant status in patients with CP.

METHODS

In a placebo-controlled double blind trial, consecutive patients with CP were randomized to groups that were given placebo or antioxidants for 6 months. The primary outcome measure was pain relief, and secondary outcome measures were analgesic requirements, hospitalization, and markers of oxidative stress (thiobarbituric acid-reactive substances [TBARS]) and antioxidant status (ferric-reducing ability of plasma [FRAP]).

RESULTS

Patients (age 30.5+/-10.5 years, 86 male, 35 alcoholic, and 92 with idiopathic CP) were assigned to the placebo (n=56) or antioxidant groups (n=71). After 6 months, the reduction in the number of painful days per month was significantly higher in the antioxidant group compared with the placebo group (7.4+/-6.8 vs 3.2+/-4, respectively; P< .001; 95% CI, 2.07, 6.23). The reduction in the number of analgesic tablets per month was also higher in the antioxidant group (10.5+/-11.8 vs 4.4+/-5.8 respectively; P= .001; 95% CI, 2.65, 9.65). Furthermore, 32% and 13% of patients became pain free in the antioxidant and placebo groups, respectively (P= .009). The reduction in the level of TBARS and increase in FRAP were significantly higher in the antioxidant group compared with the placebo group (TBARS: placebo 1.2+/-2.7 vs antioxidant 3.5+/-3.4 nmol/mL; P= .001; 95% CI 0.96, 3.55; FRAP: placebo -5.6+/-154.9 vs antioxidant 97.8+/-134.9 microMFe(+2) liberated, P= .001, 95% CI 44.98, 161.7).

CONCLUSIONS

Antioxidant supplementation was effective in relieving pain and reducing levels of oxidative stress in patients with CP.

Pain in chronic pancreatitis and pancreatic cancer

Chronic, debilitating abdominal pain is arguably the most important component of chronic pancreatitis, leading to significant morbidity and disability. Attempting to treat this pain, which is too often unsuccessful, is a frustrating experience for physician and patient. Multiple studies to improve understanding of the pathophysiology that causes pain in some patients but not in others have been performed since the most recent reviews on this topic. In addition, new treatment modalities have been developed and evaluated in this population. This review discusses new advances in neuroscience and the study of visceral pain mechanisms, as well as genetic factors that may play a role. Updates of established therapies, as well as new techniques used in addressing pain from chronic pancreatitis, are reviewed. Lastly, outcome measures, which have been highly variable in this field over the years, are addressed.