Changing phenotype and disease behaviour of chronic pancreatitis in India: evidence for gene-environment interactions

Transcriptomic analysis of pancreatic tissue from humans and mice identifies potential gene signatures and unexplored pathways during progression from acute to chronic pancreatitis

BACKGROUND

A comprehensive understanding of the molecular pathogenesis of chronic pancreatitis (CP), a fibroinflammatory disorder of the pancreas, is warranted for the development of targeted therapies. The current study focused on comparing the transcriptomes of pancreatic tissues obtained from patients with CP with those of two rodent models of chemically induced CP to identify dysregulated genes/signaling pathways.

METHODS

Pancreatitis was induced in mice using cerulein and L-arginine. Pancreatic tissues were obtained from humans and mice. The RNA was isolated, and the transcriptomes were generated using the GeneChip Human Transcriptome Array 2.0 and Clariom D Mouse Array respectively. Differentially expressed genes with log2-fold changes ≥ +2 and ≤ -2 were considered for functional and signaling pathway enrichment analysis. The expression of NUCB2, which plays a role in β-cell function, was validated by ELISA in acute pancreatitis (AP) and immune cell responses in AP and CP using flow cytometry.

RESULTS

The current study identifies L-arginine-induced CP as a better model for investigating the pathogenesis of human CP, with greater similarity in dysregulated genes (22%), transcription factors (34%) and enriched pathways (58%) compared to cerulein model (2%, 11% and 9%) respectively. Nesfatin-1, encoded by NUCB2, was decreased in patients with AP (12% nondiabetic, 41% post pancreatitis diabetes). The Th1 immune cell response was greater in the patients with AP (44%), whereas Th17 immune response was greater in patients with CP (18%).

CONCLUSION

Our study highlights potential novel and unexplored pathways involved in inflammation, fibrosis, and pain in CP and paves the way for testing them as putative drug targets using a severe disease model.

The causality between use of glucocorticoids and risk of pancreatitis: a Mendelian randomization study

Background and aim

To date, the association between glucocorticoid use and the risk of pancreatitis remains controversial. The aim of this study was the investigation of this possible relationship.

Methods

We carried out a two-sample Mendelian randomization (MR) analysis using GWAS data from European ancestry, East Asian descendants and the FinnGen Biobank Consortium to evaluate this potential causal relationship. Genetic variants associated with glucocorticoid use were selected based on genome-wide significance (p < 5×10-8).

Results

Our MR analysis of European ancestry data revealed no significant causal relationship between glucocorticoid use and AP (IVW: OR=1.084, 95% CI= 0.945-1.242, P=0.249; MR-Egger: OR=1.049, 95% CI= 0.686-1.603, P=0.828; weighted median: OR=1.026, 95% CI= 0.863-1.219, P=0.775) or CP (IVW: OR=1.027, 95% CI= 0.850-1.240, P=0.785; MR-Egger: OR= 1.625, 95% CI= 0.913-2.890, P= 0.111; weighted median: OR= 1.176, 95% CI= 0.909-1.523, P= 0.218). Sensitivity analyses, including MR-Egger and MR-PRESSO, indicated no evidence of pleiotropy or heterogeneity, confirming the robustness of our findings. Multivariable MR analysis adjusted for alcohol consumption, BMI, cholelithiasis and C-reactive protein levels supported these findings. Replicated analysis was performed on datasets from the FinnGen Biobank Consortium and East Asian descendants, and similar results were obtained.

Conclusions

This MR analysis suggests that there is no causal association between glucocorticoid use and the risk of pancreatitis.

My 40-Year Encounter with ERCP: A Saga of Service, Syndromes, and Solutions

Endoscopic retrograde cholangiopancreatography (ERCP) has been a significant development in gastrointestinal endoscopy. I did my first ERCP at SKIMS on December 5, 1982, and over the last 40 years, I have performed 10,100 ERCP procedures, including 600 Sphincter of Oddi manometries (SOM), and 3200 therapeutic ERCPs. We were confronted with many clinical challenges that needed answers by applying ERCP as a primary diagnostic tool. These studies gave birth to and/or recognition of several clinical syndromes. The hepatobiliary and pancreatic ascariasis (HBPA) as a clinical disease was recognized in 1985. The nematode, Ascaris lumbricoides, was the most common cause of hepatobiliary and pancreatic diseases in Kashmir, and its impact on healthcare, clinical profile, management policies, and control measures was identified. Kashmir was recognized as an endemic zone for recurrent pyogenic cholangitis (RPC), which constituted 12.5% of all biliary diseases. RPC in this population was found essentially to be an aftermath of HBPA. A subset of patients with hepatic hydatidosis with rupture into the biliary tract was recognized at ERCP and primarily treated by endotherapy. Cholangiographic abnormalities in children with portal cavernoma evolved into the recognition of portal biliopathy. Extensive studies of the sphincter of Oddi manometry in patients with unexplained biliary and/or pancreatic pain following cholecystectomy identified the entity of the sphincter of Oddi dyskinesia (SOD). In a cross-over trial, Nifedipine, compared with a placebo, showed a significant clinical response in 20 of 28 such patients. ERCP studies done in patients with tropical calcific pancreatitis showed an anomalous union of bile and pancreatic ducts. Forty of the 220 patients with liver transplantation had biliary complications namely biliary leaks, bile duct strictures, SOD, and recurrence of underlying primary biliary cholangitis. Biliary complications caused considerable morbidity and mortality in patients with liver transplantation.

Idiopathic chronic pancreatitis: Beyond antioxidants

Chronic pancreatitis (CP) is a complex disease associated with gene-gene or gene-environment interactions. The incidence of idiopathic CP has shown an increasing trend, withits phenotypeshaving changed considerably in the last two decades. The diseaseitself can be regulated before it reaches the stage of established CP; however, the etiopathogenesis underlying idiopathic CP remains to be established, making the condition difficult to cure. Unfortunately, there also remains a lack of consensus regarding the beneficial effects of antioxidant therapiesfor CP. It is known that antioxidant therapy does not reduce inflammatory and fibrotic cytokines, making it unlikely that they could modulate the disease process. Although antioxidants are safe, very few studies to date have reported the long-term beneficial effects in patients with CP. Thus, studies are being performed to identify drugs that can improve symptoms and alter the natural history of CP. Statins, with their numerous pleiotropic effects, may play a role in the treatment of CP, butin 2006, their use was found to be associated with the undesirable side effect of promoting pancreatitis. Latter studies showed favourable effects of statins in CP, highlighting the particular benefits of lipophilic statins, such as lovastatin and simvastatin, over the hydrophilic statins, such as rosuvastatin. Ultimately, studies to repurpose N-acetylcysteine as a CP therapy areyielding very promising results.

Nuclear receptor subfamily 5 group A member 2 (NR5A2): role in health and diseases

Nuclear receptors are the regulatory molecules that mediate cellular signals as they interact with specific DNA sequences. NR5A2 is a member of NR5A subfamily having four members (Nr5a1-Nr5a4). NR5A2 shows involvement in diverse biological processes like reverse cholesterol transport, embryonic stem cell pluripotency, steroidogenesis, development and differentiation of embryo, and adult homeostasis. NR5A2 haploinsufficiency has been seen associated with chronic pancreatitis, pancreatic and gastrointestinal cancer. There is a close relationship between the progression of pancreatic cancer from chronic pancreatitis, NR5A2 serving a common link. NR5A2 activity is regulated by intracellular phospholipids, transcriptional coregulators and post-translational modifications. The specific ligand of NR5A2 is unknown hence called an orphan receptor, but specific phospholipids such as dilauroyl phosphatidylcholine and diundecanoyl phosphatidylcholine act as a ligand and they are established drug targets in various diseases. This review will focus on the NR5A2 structure, regulation of its activity, and role in biological processes and diseases. In future, need more emphasis on discovering small molecule agonists and antagonist, which act as a drug target for therapeutic applications.

International consensus guidelines on surveillance for pancreatic cancer in chronic pancreatitis. Recommendations from the working group for the international consensus guidelines for chronic pancreatitis in collaboration with the International Association of Pancreatology, the American Pancreatic Association, the Japan Pancreas Society, and European Pancreatic Club

BACKGROUND

Patients with chronic pancreatitis (CP) have an increased risk of pancreatic cancer. We present the international consensus guidelines for surveillance of pancreatic cancer in CP.

METHODS

The international group evaluated 10 statements generated from evidence on 5 questions relating to pancreatic cancer in CP. The GRADE approach was used to evaluate the level of evidence available per statement. The working group voted on each statement for strength of agreement, using a nine-point Likert scale in order to calculate Cronbach's alpha reliability coefficient.

RESULTS

In the following domains there was strong consensus: (1) the risk of pancreatic cancer in affected individuals with hereditary pancreatitis due to inherited PRSS1 mutations is high enough to justify surveillance; (2) the risk of pancreatic cancer in patients with CP associated with SPINK1 p. N34S is not high enough to justify surveillance; (3) surveillance should be undertaken in pancreatic specialist centers; (4) surveillance should only be introduced after the age of 40 years and stopped when the patient would no longer be suitable for surgical intervention. All patients with CP should be advised to lead a healthy lifestyle aimed at avoiding risk factors for progression of CP and pancreatic cancer. There was only moderate or weak agreement on the best methods of screening and surveillance in other types of environmental, familial and genetic forms of CP.

CONCLUSIONS

Patients with inherited PRSS1 mutations should undergo surveillance for pancreatic cancer, but the best methods for cancer detection need further investigation.

Clinical and Practice Variations in Pediatric Acute Recurrent or Chronic Pancreatitis: Report From the INSPPIRE Study

OBJECTIVE

The aim of the study was to determine whether clinical characteristics and management of pediatric acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP) differ across INSPPIRE (INternational Study Group of Pediatric Pancreatitis: In Search for a cuRE) sites.

STUDY DESIGN

Data were collected from INSPPIRE and analyzed per US regions and "non-US" sites. Between-group differences were compared by Pearson chi-square test. Differences in disease burden were compared by Kruskal-Wallis test.

RESULTS

Out of the 479 subjects, 121 (25%) were enrolled in West, 151 (32%) Midwest, 45 Northeast (9%), 78 (16%) South, and 84 (18%) at non-US sites. Hispanic ethnicity was more common in South (P < 0.0001); white race in Northeast (P = 0.009). CP was less common and time from diagnosis of first acute pancreatitis to CP was longer in children at non-US sites (P = 0.0002 and P = 0.011, respectively). Genetic mutations were most common among all groups; PRSS1 variants predominated in Midwest (P = 0.002). Gallstones were more frequent in South (P = 0.002). Endoscopic retrograde cholangiopancreatography (ERCP) and computed tomography (CT) imaging were more commonly utilized in United States compared with non-United States (P < 0.0001), but there were no differences in the use of MRI/MRCP. Disease burden was highest in the West and Midwest, possibly as total pancreatectomy and islet autotransplantation (TPIAT) referral sites were located in these regions. All therapies were less commonly administered in non-US sites (P < 0.0001).

CONCLUSIONS

This is the first study to describe geographical variations in the INSPPIRE cohort, which possibly reflect variations in practice and referral patterns. The underlying reason behind the lower frequency of CP and fewer treatments in non-United States sites need to be further explored.

Effects of PRSS1-PRSS2 rs10273639, CLDN2 rs7057398 and MORC4 rs12688220 polymorphisms on individual susceptibility to pancreatitis: A meta-analysis

BACKGROUND

Genetic association studies regarding relationship between PRSS1-PRSS2 rs10273639/CLDN2 rs7057398/MORC4 rs12688220 polymorphisms and pancreatitis yielded conflicting results. We performed this meta-analysis to explore associations between these polymorphisms and pancreatitis in a larger pooled population.

METHODS

A systematic search of the literature was conducted for eligible studies. We used Review Manager to conduct statistical analyses.

RESULTS

Fifteen studies were included in this meta-analysis. The results of pooled analyses showed that CLDN2 rs7057398, MORC4 rs12688220 and PRSS1-PRSS2 rs10273639 polymorphisms were all significantly associated with susceptibility to acute pancreatitis in Caucasians. Moreover, MORC4 rs12688220 and PRSS1-PRSS2 rs10273639 polymorphisms were also significantly associated with susceptibility to chronic pancreatitis in Asians.

CONCLUSIONS

Our findings suggested that rs7057398, rs12688220 and rs10273639 polymorphisms could be used to identify individuals at an elevated susceptibility to acute pancreatitis in Caucasians. Moreover, rs12688220 and rs10273639 polymorphisms could be used to identify individuals at an elevated susceptibility chronic pancreatitis in Asians.

Myths and realities about alcohol and smoking in chronic pancreatitis

PURPOSE OF REVIEW

Alcohol and smoking play an important role in pancreatitis. The present review will address the myths and evidences about alcohol and smoking with pancreatitis to help improve the approach of healthcare professionals when managing of these patients.

RECENT FINDINGS

There is a growing recognition that chronic pancreatitis is a multifactorial disease. Eliciting an accurate history of alcohol consumption and smoking from patients, and if necessary, family members, can help determine their contribution to the patient's disease. In the absence of a convincing history, physicians should be open to consideration of other etiologies. The amount and duration of alcohol consumption is the most important determinant in increasing pancreatitis risk. Alcohol sensitizes the pancreas to other insults or injury and promotes disease progression. Smoking is an independent risk factor or chronic pancreatitis and has synergistic pathogenic effects with alcohol. The natural history of chronic pancreatitis is highly variable. A patient with alcoholic pancreatitis can have symptoms, recurrences or exacerbations from disease-related complications or nonpancreatic causes. Novel strategies are needed to enable patients quit smoking.

SUMMARY

Obtaining accurate history, appropriate evaluation and management can help to achieve meaningful improvement in symptoms in patients with chronic pancreatitis. Abstinence from alcohol and smoking cessation, when applicable, should be recommended in all patients to prevent disease recurrences and progression.