trypsinogen and Pancreatitis--Chronic

PRSS1 and PRSS2 constitute the only functional copies of a tandemly-arranged five-trypsinogen-gene cluster (i.e., PRSS1, PRSS3P1, PRSS3P2, TRY7 and PRSS2) on chromosome 7q35. Variants in PRSS1 and PRSS2, including missense and copy number variants (CNVs), have been reported to predispose to or protect against chronic pancreatitis (CP). We wondered whether a common trypsinogen pseudogene deletion CNV (that removes two of the three trypsinogen pseudogenes, PRSS3P2 and TRY7) might be associated with CP causation/predisposition.. We analyzed the common PRSS3P2 and TRY7 deletion CNV in a total of 1536 CP patients and 3506 controls from France, Germany, India and Japan by means of quantitative fluorescent multiplex polymerase chain reaction.. We demonstrated that the deletion CNV variant was associated with a protective effect against CP in the French, German and Japanese cohorts whilst a trend toward the same association was noted in the Indian cohort. Meta-analysis under a dominant model yielded a pooled odds ratio (OR) of 0.68 (95% confidence interval (CI) 0.52-0.89; p = 0.005) whereas an allele-based meta-analysis yielded a pooled OR of 0.84 (95% CI 0.77-0.92; p = 0.0001). This protective effect is explicable by reference to the recent finding that the still functional PRSS3P2/TRY7 pseudogene enhancers upregulate pancreatic PRSS2 expression.. The common PRSS3P2 and TRY7 deletion CNV was associated with a reduced risk for CP. This finding provides additional support for the emerging view that dysregulated PRSS2 expression represents a discrete mechanism underlying CP predisposition or protection.

Topics: Alleles; DNA Copy Number Variations; Genetic Predisposition to Disease; Genotype; Humans; Mutation; Pancreatitis, Chronic; Trypsin; Trypsinogen

Since the description of the PRSS1 gene encoding the cationic trypsinogen as being involved in dominant hereditary pancreatitis, more than 50 PRSS1 gene variants have been reported. Among those that have been classified as pathogenic, some have a high penetrance and others have a low penetrance. Assessing the clinical relevance of PRSS1 variants is often complicated in the absence of functional evidence and interpretation regarding rare variants is not very easy in clinical practice. The aim of this study was to review the PRSS1 variants and to classify them according to their degree of deleterious effect. This classification was based on the results of in vitro experiments and on population data, in comparing the allelic frequency of each variant in patients with pancreatitis and in unaffected individuals. This review should help geneticists and clinicians in charge of patient...s care and genetic counseling to interpret results of genetic studies.

Topics: Humans; Mutation; Pancreatitis, Chronic; Trypsin; Trypsinogen

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

Topics: Asian People; Claudins; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Nuclear Proteins; Pancreatitis; Pancreatitis, Chronic; Polymorphism, Genetic; Trypsin; Trypsinogen; White People

Exocrine pancreatic insufficiency in children can lead to lifelong complications related to malnutrition and poor growth. The clinical presentation can be subtle in the early stages of insufficiency as the large functional capacity of the pancreas is gradually lost. The pediatrician plays a crucial role in the early identification of these children to ensure a timely referral so that a diagnosis can be made and therapy initiated. Early nutritional therapy allows for prevention and correction of deficiencies, which leads to improved outcomes and survival. When insufficiency is suspected, the workup should start with an indirect test of exocrine pancreatic function, such as fecal elastase, to establish the diagnosis. Once a diagnosis is established, further testing to delineate the etiology should be pursued, with cystic fibrosis being high on the differential list and assessed for with a sweat test. Assessment of anthropometry at every visit is key, as is monitoring of laboratory parameters and physical examination findings that are suggestive of malabsorption and malnutrition. The mainstay of management is administration of exogenous pancreatic enzymes to facilitate digestion and absorption. [Pediatr Ann. 2019;48(11):e441-e447.].

Topics: Acyl-CoA Dehydrogenase, Long-Chain; Anus, Imperforate; Child; Child Nutrition Disorders; Chymotrypsin; Congenital Bone Marrow Failure Syndromes; Cystic Fibrosis; Dietary Fats; Ectodermal Dysplasia; Enzyme Replacement Therapy; Exocrine Pancreatic Insufficiency; Feces; Growth Disorders; Hearing Loss, Sensorineural; Humans; Hypothyroidism; Intellectual Disability; Lipid Metabolism, Inborn Errors; Mitochondrial Diseases; Muscular Diseases; Nose; Nutrition Assessment; Pancreas; Pancreatic Diseases; Pancreatic Elastase; Pancreatic Function Tests; Pancreatitis, Chronic; Shwachman-Diamond Syndrome; Steatorrhea; Trypsinogen

This review focuses on seven aspects of physiology and pathophysiology of the exocrine pancreas that have been intensively discussed and studied within the past few years: (1) the role of neurohormonal mechanisms like melatonin, leptin, or ghrelin in the stimulation of pancreatic enzyme secretion; (2) the initiation processes of acute pancreatitis, like fusion of zymogen granules with lysosomes leading to intracellular activation of trypsinogen by the lysosomal enzyme cathepsin B, or autoactivation of trypsinogen; (3) the role of genes in the pathogenesis of acute pancreatitis; (4) the role of alcohol and constituents of alcoholic beverages in the pathogenesis of acute pancreatitis; (5) the role of pancreatic hypertension, neuropathy, and central mechanisms for the pathogenesis of pain in chronic pancreatitis; (6) the relation between exocrine pancreatic function and diabetes mellitus; and (7) pathophysiology, diagnosis and treatment of pancreatic steatorrhea.

Topics: Cathepsin B; Diabetes Mellitus; DNA Mutational Analysis; Ghrelin; Leptin; Melatonin; Pancreas; Pancreatic Juice; Pancreatitis, Acute Necrotizing; Pancreatitis, Alcoholic; Pancreatitis, Chronic; Trypsinogen

In this article, we review important advances in our understanding of the mechanisms of pancreatitis.. The relative contributions of intrapancreatic trypsinogen activation and nuclear factor kappa B (NFκB) activation, the two major early independent cellular events in pancreatitis, have been investigated using novel genetic models. Trypsinogen activation has traditionally held the spotlight for many decades as the central pathogenic event of pancreatitis. However, recent experimental evidence points to the role of trypsin activation in early acinar cell damage but not in the inflammatory response of acute pancreatitis, which was shown to be induced by NFκB activation. Further, chronic pancreatitis developed independently of trypsinogen activation in the caerulein model. Sustained NFκB activation, but not persistent intra-acinar expression of active trypsin, was shown to result in chronic pancreatitis. Calcineurin-NFAT (nuclear factor of activated T-cells) signaling was shown to mediate downstream effects of pathologic rise in intracellular calcium. Interleukin-6 was identified as a key cytokine mediating pancreatitis-associated lung injury.. Recent advances challenge the long-believed trypsin-centered understanding of pancreatitis. It is becoming increasingly clear that activation of intense inflammatory signaling mechanisms in acinar cells is crucial to the pathogenesis of pancreatitis, which may explain the strong systemic inflammatory response in pancreatitis.

Topics: Acute Disease; Genetic Predisposition to Disease; Humans; Mutation; NF-kappa B; Pancreatitis; Pancreatitis, Chronic; Signal Transduction; Systemic Inflammatory Response Syndrome; Trypsin; Trypsinogen

Chronic pancreatitis (CP) is a disease characterized by irreversible destruction and fibrosis of the parenchyma, leading to pancreatic exocrine insufficiency. In developed countries, the etiology for 60% to 70% of CP amongst male patients is alcohol and 25% are classified as idiopathic chronic pancreatitis (ICP). The genetic predisposition to CP could be an inappropriate activation of trypsinogen in the pancreas. Two common haplotypes, c.101A>G (p.N34S) and c.-215G>A, and four intronic alterations of the serine protease inhibitor Kazal type 1 (SPINK1) gene have been found to increase the risk for CP in the Asia Pacific region. Hence, SPINK1 is thought to be a candidate gene for pancreatitis. A loss-of-function alteration in chymotrypsinogen C (CTRC) gene has been shown to be associated with tropical calcific pancreatitis (TCP). Cathepsin B (CTSB) is also found to be associated with TCP. However mutations in cationic and anionic trypsinogen gene do not play an important role in causing CP in Asia Pacific region.

Topics: Asia; Carrier Proteins; Cathepsin B; Chymotrypsin; Genetic Association Studies; Humans; Oceania; Pancreatitis, Chronic; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsin Inhibitors; Trypsinogen

This review focuses on studies from the past year that highlight molecular and cellular mechanisms of pancreatic injury arising from acute and chronic pancreatitis.. Factors that induce or ameliorate injury as well as cellular pathways involved have been examined. Causative or sensitizing factors include refluxed bile acids, hypercalcemia, ethanol, hypertriglyceridemia, and acidosis. In addition, the diabetes drug exendin-4 has been associated with pancreatitis, whereas other drugs may reduce pancreatic injury. The intracellular events that influence disease severity are better understood. Cathepsin-L promotes injury through an antiapoptotic effect, rather than by trypsinogen activation. In addition, specific trypsinogen mutations lead to trypsinogen misfolding, endoplasmic reticulum stress, and injury. Endogenous trypsin inhibitors and upregulation of proteins including Bcl-2, fibroblast growth factor 21, and activated protein C can reduce injury. Immune cells, however, have been shown to increase injury via an antiapoptotic effect.. The current findings are critical to understanding how causative factors initiate downstream cellular events resulting in pancreatic injury. Such knowledge will aid in the development of targeted treatments for pancreatitis. This review will first discuss factors influencing pancreatic injury, and then conclude with studies detailing the cellular mechanisms involved.

Topics: Animals; Apoptosis; Endoplasmic Reticulum; Humans; Pancreas; Pancreatitis, Acute Necrotizing; Pancreatitis, Chronic; Trypsin; Trypsinogen

Chronic pancreatitis is known to be a heterogeneous disease with varied etiologies. Tropical calcific pancreatitis (TCP) is a severe form of chronic pancreatitis unique to developing countries. With growing evidence of genetic factors contributing to the pathogenesis of TCP, this review is aimed at compiling the available information in this field. We also propose a two hit model to explain the sequence of events in the pathogenesis of TCP.

Topics: Calcinosis; Carrier Proteins; Genetic Predisposition to Disease; Humans; Mutation; Pancreatitis, Chronic; Tropical Climate; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Topics: Abdominal Pain; Adult; Age of Onset; Calculi; Child; Developing Countries; Diabetes Mellitus; Humans; Malnutrition; Manihot; Mutation; Oxidative Stress; Pancreatic Diseases; Pancreatic Neoplasms; Pancreatitis, Chronic; Steatorrhea; Tropical Climate; Trypsin; Trypsinogen

Tropical calcific pancreatitis (TCP) is a subtype of chronic pancreatitis which is unique to tropical regions. Patients present at young age with recurrent abdominal pain, nutritional deficiencies, and insulin-requiring diabetes. For a long time, the aetiology of this disorder was poorly understood. Several environmental factors, such as malnutrition or the consumption of toxic food components such as cyanogenic glycosides, were proposed as pathogenic factors. In the last decade, a major impact on the understanding of the aetiology of TCP has come from genetic studies on hereditary and idiopathic chronic pancreatitis. Genetic alterations in at least five genetic loci are clearly associated with chronic pancreatitis in the Western world. These include alterations in genes coding for trypsinogens, the most abundant digestive enzymes (PRSS1 and PRSS2), the trypsin inhibitor (SPINK1) and the trypsin-degrading enzyme, chymotrypsinogen C (CTRC). In addition, alterations in the cystic fibrosis (CFTR) gene are associated with idiopathic pancreatitis. TCP clinically resembles non-alcoholic chronic pancreatitis of Western countries, suggesting that similar genetic defects might also be of importance in this disease entity. Indeed, alterations in at least two genes, SPINK1 and CTRC, are strongly associated with TCP. The current review focuses on the recent developments in the understanding of the genetic basis of inherited pancreatitis, with special emphasis on TCP.

Topics: Calcinosis; Humans; Models, Biological; Pancreatitis, Chronic; Signal Transduction; Tropical Climate; Trypsinogen

Chronic pancreatitis is a persistent inflammatory disorder of the pancreas, characterized by destruction of the pancreatic parenchyma, maldigestion, chronic pain and diabetes mellitus. Genetic factors determining susceptibility to chronic pancreatitis can be classified in two groups: 1. rare gene mutations affecting the cationic trypsinogen gene that directly cause the disease, and 2. genetic variants that increase the risk for chronic pancreatitis but require additional risk factors to precipitate the disease. These gene variants are considered genetic risk factors, which emerged during the past decade and now represent a clinically important etiological category. Susceptibility to chronic pancreatitis is inherited in a complex manner, which can involve alterations in several genes conferring various degrees of risk. The biochemical mechanism behind the genetic risk includes increased ectopic activation of the digestive enzyme trypsin in the pancreas and failure of protective mechanisms responsible for trypsin inactivation.

Topics: Carrier Proteins; Chymotrypsin; Cystic Fibrosis Transmembrane Conductance Regulator; Genetic Predisposition to Disease; Genetic Variation; Humans; Mutation; Pancreatitis, Chronic; Risk Factors; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

In 1996, shortly after a locus for hereditary pancreatitis had been mapped to chromosome 7q35, an apparent gain-of-function missense mutation, p.R122H, in the cationic trypsinogen gene (PRSS1) was identified. Thereafter, the search for chronic pancreatitis-associated genetic factors has been largely focused on one form of genetic variation, namely, single nucleotide substitutions (SNSs). Only very recently has another type of genetic variation - copy number variations (CNVs) - been found to cause the disease. First, we identified duplication and triplication of an approximately 605 kb segment on chromosome 7q35 in French white patients with hereditary or idiopathic chronic pancreatitis. These alterations increased the copy number of PRSS1 as well as PRSS2, which encodes anionic trypsinogen. Second, we characterized a hybrid trypsinogen gene, in which exons 1 and 2 were derived from PRSS2 and exons 3 to 5 from PRSS1. Interestingly, this hybrid gene had two independent gain-of-function effects: increased trypsinogen gene copy number and it contained the p.N29I pancreatitis-causing missense mutation. Lastly, we identified two loss-of-function copy number mutations (deletions) in the SPINK1 gene, which encodes pancreatic secretory trypsin inhibitor (PSTI). Particularly, in one family with chronic pancreatitis, deletion of the complete SPINK1 gene was co-inherited with a CFTR missense mutation (p.L997F), revealing another layer of complexity between CNV and SNS interactions in the determination of a given disease phenotype. These findings represent a further demonstration of how studies of CNVs have altered the landscape of genetic research in the past few years and offer a fresh glimpse into the exciting realm of human CNVs.

Topics: Gene Dosage; Gene Duplication; Genome; Humans; Mutation; Pancreatitis, Chronic; Trypsinogen

Hereditary chronic pancreatitis (HCP) is a very rare form of early-onset chronic pancreatitis. Apart from young age at diagnosis and a slower progression, the clinical course, morphological features and laboratory findings of HCP do not differ from those of patients with alcoholic chronic pancreatitis. Diagnostic criteria and treatment of HCP also resemble those of chronic pancreatitis of other causes. The clinical presentation is highly variable and includes chronic abdominal pain, impairment of endocrine and exocrine pancreatic function, nausea and vomiting, maldigestion, diabetes, pseudocysts, bile-duct and duodenal obstruction, and rarely pancreatic cancer. Fortunately, the disease is mild in most patients. Mutations in the PRSS1 gene, encoding cationic trypsinogen, play a causative role in chronic pancreatitis. It has been shown that the PRSS1 mutations increase autocatalytic conversion of trypsinogen to active trypsin, and thus probably cause premature, intrapancreatic trypsinogen activation, disturbing the intrapancreatic balance of proteases and their inhibitors. Other genes--such as the anionic trypsinogen (PRSS2), the serine protease inhibitor Kazal type 1 (SPINK1), and the cystic fibrosis transmembrane conductance regulator (CFTR)--have also been found to be associated with chronic pancreatitis (idiopathic and hereditary). Genetic testing should only be performed in carefully selected patients by direct DNA sequencing, and antenatal diagnosis should not be encouraged. Treatment focuses on enzyme and nutritional supplementation, pain management, pancreatic diabetes, and local organ complications such as pseudocysts and bile-duct or duodenal obstruction. The disease course and prognosis of patients with HCP is unpredictable. The risk of pancreatic cancer is elevated. Therefore, HCP patients should strongly avoid environmental risk factors for pancreatic cancer.

Topics: Animals; Carrier Proteins; Cystic Fibrosis Transmembrane Conductance Regulator; Diagnosis, Differential; Genetic Counseling; Genetic Predisposition to Disease; Humans; Models, Animal; Mutation; Pancreatic Neoplasms; Pancreatitis, Chronic; Prenatal Diagnosis; Prognosis; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

There was remarkable progress in the understanding of the role genetic risk factors in chronic pancreatitis. These factors seem to be much more important than thought in the past. The rare autosomal-dominant mutations N29I and R122H of PRSS1 (cationic trypsinogen) as well as the variant N34S of SPINK1 (pancreatic secretory trypsin inhibitor) are associated to a disease onset in childhood or youth. Compared to chronic alcoholic pancreatitis the progression is slow so that for a long time only signs of acute-recurrent pancreatitis are found. Only at later time points (more than 10-15 years) there is evidence for chronic pancreatitis in the majority of patients. Acute recurrent pancreatitis may therefore be regarded as a transition state until definite signs of chronic pancreatitis are detectable.

Topics: Carrier Proteins; Cystic Fibrosis Transmembrane Conductance Regulator; Genetic Predisposition to Disease; Humans; Mutation; Pancreatitis; Pancreatitis, Chronic; Recurrence; Risk Factors; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Chronic pancreatitis is an inflammatory disease of the pancreas leading to progressive fibrosis that presents with severe abdominal pain and may result in exocrine and/or endocrine insufficiency at later stages. Although alcohol is the strongest contributing factor for disease development, some patients feature none of the known classical risk factors and were consequently classified as having idiopathic or, in the presence of a positive family history, hereditary disease. Today, several mutations have been identified that predispose carriers to development of chronic pancreatitis. The genetic studies of the past decade have clearly contributed to a better understanding of the disease's pathogenesis. Currently known mutations associated with chronic pancreatitis and the implications for clinicians are discussed in this review.

Topics: Chymotrypsin; Cystic Fibrosis Transmembrane Conductance Regulator; Female; Gene Expression Regulation; Genetic Predisposition to Disease; Genetic Testing; Humans; Incidence; Male; Mutation; Pancreatitis, Chronic; Practice Guidelines as Topic; Prognosis; Risk Assessment; Trypsinogen

Hereditary chronic pancreatitis (HCP) is a very rare form of early onset chronic pancreatitis. With the exception of the young age at diagnosis and a slower progression, the clinical course, morphological features and laboratory findings of HCP do not differ from those of patients with alcoholic chronic pancreatitis. As well, diagnostic criteria and treatment of HCP resemble that of chronic pancreatitis of other causes. The clinical presentation is highly variable and includes chronic abdominal pain, impairment of endocrine and exocrine pancreatic function, nausea and vomiting, maldigestion, diabetes, pseudocysts, bile duct and duodenal obstruction, and rarely pancreatic cancer. Fortunately, most patients have a mild disease. Mutations in the PRSS1 gene, encoding cationic trypsinogen, play a causative role in chronic pancreatitis. It has been shown that the PRSS1 mutations increase autocatalytic conversion of trypsinogen to active trypsin, and thus probably cause premature, intrapancreatic trypsinogen activation disturbing the intrapancreatic balance of proteases and their inhibitors. Other genes, such as the anionic trypsinogen (PRSS2), the serine protease inhibitor, Kazal type 1 (SPINK1) and the cystic fibrosis transmembrane conductance regulator (CFTR) have been found to be associated with chronic pancreatitis (idiopathic and hereditary) as well. Genetic testing should only be performed in carefully selected patients by direct DNA sequencing and antenatal diagnosis should not be encouraged. Treatment focuses on enzyme and nutritional supplementation, pain management, pancreatic diabetes, and local organ complications, such as pseudocysts, bile duct or duodenal obstruction. The disease course and prognosis of patients with HCP is unpredictable. Pancreatic cancer risk is elevated. Therefore, HCP patients should strongly avoid environmental risk factors for pancreatic cancer.

Topics: Adult; Animals; Carrier Proteins; Child; Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator; Databases, Genetic; Diagnosis, Differential; Disease Models, Animal; Genetic Counseling; Genetic Predisposition to Disease; Genetic Testing; Humans; Mice; Mutation; Pancreatic Neoplasms; Pancreaticojejunostomy; Pancreatitis, Chronic; Prognosis; Rats; Risk Factors; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Diagnosis of chronic pancreatitis in its early stage is an extremely difficult task. If the genetic predispositions are identified, it may help make possible the earlier diagnosis of chronic pancreatitis or the detection of patients at risk. There are two major hypotheses about the pathogenesis of chronic pancreatitis known as the "necrosis-fibrosis" and "pancreatic stone protein" hypotheses. Recent molecular and genetic evidence suggests that both pathways contribute to the pathogenesis of chronic pancreatitis. Chronic pancreatitis may be caused by either increased proteolytic activity [the cationic trypsinogen (PRSS1) gene] or decreased protease inhibition (the pancreatic secretory trypsin inhibitor (PSTI) gene]. The impaired pancreatic duct function [cystic fibrosis transmembrane conductance regulator (CFTR) gene] may also be involved in the pathogenesis of the disease. Except for PRSS1 mutations, the known genetic risk for chronic pancreatitis is not high. The high individual variability and low incidence of chronic pancreatitis suggest that yet unidentified genetic and environmental factors are important. Further genetic analysis is necessary for understanding the pathogenesis of chronic pancreatitis, which may be helpful for the earlier diagnosis of the juvenile- or young-onset disease.

Topics: Carrier Proteins; Cystic Fibrosis Transmembrane Conductance Regulator; DNA Mutational Analysis; Early Diagnosis; Humans; Pancreatitis, Chronic; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Acute pancreatitis is an increasingly common and sometimes severe disease for which there is little specific therapy. Chronic pancreatitis is a common and grossly debilitating sequel that is largely irreversible, whatever treatment is adopted. In the face of these burdens, the absence of specific treatments is a spur to research. The acinar cell is the primary target of injury from alcohol metabolites, bile, hyperlipidaemia, hyperstimulation and other causes. These induce abnormal, prolonged, global, cytosolic calcium signals, the prevention of which also prevents premature digestive enzyme activation, cytokine expression, vacuole formation and acinar cell necrosis. Such agents increase calcium entry through the plasma membrane and/or increase calcium release from intracellular stores, shown to result from effects on calcium channels and calcium pumps, or their energy supply. A multitude of signalling mechanisms are activated, diverted or disrupted, including secretory mechanisms, lysosomal regulators, inflammatory mediators, cell survival and cell death pathways, together with or separately from calcium. While recent discoveries have increased insight and suggest prophylaxis or treatment targets, more work is required to define the mechanisms and interactions of cell signalling pathways in the pathogenesis of pancreatitis.

Topics: Adenosine Triphosphate; Animals; Calcium; Calcium Signaling; Cathepsin B; Enzyme Activation; Humans; Pancreatitis, Chronic; Trypsinogen

Topics: Carrier Proteins; Cystic Fibrosis Transmembrane Conductance Regulator; Humans; Pancreatic Neoplasms; Pancreatitis, Alcoholic; Pancreatitis, Chronic; Point Mutation; Risk Factors; Smoking; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Ten years ago, the groundwork for the discovery of the genetic basis of chronic pancreatitis was laid by linkage analyses of large kindreds with autosomal dominant hereditary chronic pancreatitis. Subsequent candidate gene sequencing of the 7q35 chromosome region revealed a strong association of the c.365G > A (p.R122 H) mutation of the PRSS1 gene encoding cationic trypsinogen with hereditary pancreatitis. In the following years, further mutations of this gene were discovered in patients with hereditary or idiopathic chronic pancreatitis. In vitro the mutations increase autocatalytic conversion of trypsinogen to active trypsin and thus probably cause premature, intrapancreatic trypsinogen activation in vivo. The clinical presentation is highly variable, but most affected mutation carriers have relatively mild disease. In this review, we summarize the current knowledge on trypsinogen mutations and their role in pancreatic diseases.

Topics: Databases, Nucleic Acid; DNA Mutational Analysis; Gene Conversion; Heterozygote; Humans; Mutation, Missense; Oligopeptides; Pancreatitis, Chronic; Penetrance; Trypsin; Trypsinogen

Topics: Carrier Proteins; Cystic Fibrosis Transmembrane Conductance Regulator; Cytochrome P-450 CYP2E1; Genetic Linkage; Genetic Markers; HLA-DR Antigens; HLA-DRB1 Chains; Humans; Keratin-8; Keratins; Mutation; Pancreatitis, Chronic; Polymorphism, Genetic; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Topics: Genetic Predisposition to Disease; Humans; Mutation; Pancreatitis, Chronic; Trypsin; Trypsinogen

Topics: Acute Disease; Animals; Chronic Disease; Mice; Pancreatitis, Chronic; Trypsin; Trypsinogen

Topics: Genetic Predisposition to Disease; Haplotypes; Humans; Mutation; Pancreatitis, Chronic; Receptors, Antigen, T-Cell; Trypsin; Trypsinogen

The study group included 105 patients with CP, with the age of the disease onset under 40 years old (the average age of onset was 26.9 years). The control group consisted of 76 persons without clinical signs of pancreatitis. The diagnosis of chronic pancreatitis in patients was made on the basis of clinical manifestations and the results of laboratory and instrumental investigations. Genetic examination of patients was conducted using the next-generation sequencing (NGS) technology and included targeted sequencing of all exons and exon-intron boundaries of the. Genetic risk factors of the CP development were found in 61% of patients. Pathogenic and likely-pathogenic variants associated with the risk of CP development were identified in the following genes:. Sequencing of the coding regions of the

Topics: Adult; Alleles; Cystic Fibrosis Transmembrane Conductance Regulator; Exons; Humans; Pancreatitis, Chronic; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

PRSS1 was the first reported chronic pancreatitis (CP) gene. The existence of both gain-of-function (GoF) and gain-of-proteotoxicity (GoP) pathological PRSS1 variants, together with the fact that PRSS1 variants have been identified in CP subtypes spanning the range from monogenic to multifactorial, has made the classification of PRSS1 variants very challenging.. All currently reported PRSS1 variants (derived primarily from two databases) were manually reviewed with respect to their clinical genetics, functional analysis and population allele frequency. They were classified by variant type and pathological mechanism within the framework of our recently proposed ACMG/AMP guidelines-based seven-category system.. The total number of distinct germline PRSS1 variants included for analysis was 100, comprising 3 copy number variants (CNVs), 12 5' and 3' variants, 19 intronic variants, 5 nonsense variants, 1 frameshift deletion variant, 6 synonymous variants, 1 in-frame duplication, 3 gene conversions and 50 missense variants. Based upon a combination of clinical genetic and functional analysis, population data and in silico analysis, we classified 26 variants (all 3 CNVs, the in-frame duplication, all 3 gene conversions and 19 missense) as "pathogenic", 3 variants (missense) as "likely pathogenic", 5 variants (four missense and one promoter) as "predisposing", 13 variants (all missense) as "unknown significance", 2 variants (missense) as "likely benign", and all remaining 51 variants as "benign".. We describe an expert classification of the 100 PRSS1 variants reported to date. The results have immediate implications for reclassifying many ClinVar-registered PRSS1 variants as well as providing optimal guidelines/standards for reporting PRSS1 variants.

Topics: Alleles; China; East Asian People; France; Gene Frequency; Genetic Predisposition to Disease; Humans; Mutation; Pancreatitis, Chronic; Trypsin; Trypsinogen

Topics: Genetic Predisposition to Disease; Humans; Mutation; Pancreatitis, Chronic; Trypsin; Trypsinogen

Topics: Animals; Humans; Mice; Mice, Transgenic; Mutation; Pancreatitis, Chronic; Trypsin; Trypsinogen

The identification of the genetic basis of hereditary pancreatitis in 1996 confirmed the critical role of trypsinogen in this disease and opened a new avenue of research on pancreatitis-associated genetic risk factors and their mechanism of action. Through the following 25 years, the ensuing discoveries fundamentally changed our understanding of pancreatitis pathogenesis, clarified the role of trypsinogen autoactivation in disease onset and progression, and set the stage for future therapeutic interventions. This Frank Brooks Memorial Lecture was delivered on November 4, 2021, at the 52nd Annual Meeting of the American Pancreatic Association, held in Miami Beach, Florida.

Topics: Humans; Pancreas; Pancreatitis, Chronic; Trypsinogen

The pathogenesis of chronic pancreatitis is still unclear. Trypsinogen activation is an active factor in acute pancreatitis that has not been studied in the occurrence of chronic pancreatitis.. Immunofluorescence was used to detect the location and expression of trypsinogen in chronic pancreatitis and normal tissues. Microarray and single-cell RNA-seq (scRNA-seq) were used to screen core genes and pathways in pancreatic stellate cells (PSCs). Western blotting and immunofluorescence were used to verify trypsinogen expression in PSCs after silencing Rabep1. Immunofluorescence and flow cytometry were used to validate trypsinogen activation and PSC activation after intervening in the endocytosis pathway.. Endocytosed trypsinogen was found in PSCs in CP clinical samples. Bioinformatic analysis showed that Rabep1 is a core gene that regulates trypsinogen endocytosis through the endocytosis pathway, verified by Western blot and immunofluorescence. Immunofluorescence and flow cytometry analyses confirmed the activation of trypsinogen and PSCs through the endocytosis pathway in PSCs.. This study discovered a new mechanism by which trypsinogen affects the activation of PSCs and the occurrence and development of CP. Through communication between pancreatic acinar cells and PSCs, trypsinogen can be endocytosed by PSCs and activated by the Rabep1 gene.

Topics: Acute Disease; Cells, Cultured; Endocytosis; Humans; Pancreatic Stellate Cells; Pancreatitis, Chronic; Trypsinogen

/Objectives: Sequence variants in several genes have been identified as being associated with an increased inherited risk to develop chronic pancreatitis (CP). In a genetic survey of a CP patient we identified in the PRSS1gene a new c.380C > G sequence variation, giving rise to a non-synonymous p.S127C mutation. Functional studies were performed to analyze the associated pathophysiology of the variant.. Following generation of an expression vector for the new PRSS1 variant we compared its expression, secretion and catalytic activity with already known PRSS1 risk variants in HEK 293T cells. The intracellular protein accumulation and induction of endoplasmic reticulum (ER)-stress was analyzed.. Prediction tool analysis indicated a probably deleterious effect of the p.S127C variant on protein function which was confirmed by detection of a secretion defect in HEK293T cells leading to intracellular protein accumulation. While protein misfolding was associated with reduced trypsin activity, the increased expression of BIP and presence of spliced XBP1 indicated that the p.S127C variant induces ER stress and activates the UPR signaling pathway.. The disease mechanism of the PRSS1 p.S127C variant involves defective protein secretion and the induction of ER-stress due to accumulation of presumably misfolded trypsinogen within the ER. The new variant should be considered disease-causing with an incomplete penetrance. Our results confirm that in addition to dysregulated trypsin-activity or reduced fluid secretion, ER-stress induction is an important trigger for acinar cell damage and the development of recurrent or chronic pancreatic inflammation.

Topics: HEK293 Cells; Humans; Mutation; Pancreatitis, Chronic; Trypsin; Trypsinogen

Topics: High-Throughput Nucleotide Sequencing; Humans; Mutation; Pancreatitis, Chronic; Trypsin; Trypsinogen

Topics: Alcoholism; Claudins; Haplotypes; Humans; Nuclear Proteins; Pancreatitis, Chronic; Polymorphism, Genetic; Trypsin; Trypsinogen

Mutations in the human serine protease 1 gene (PRSS1), which encodes cationic trypsinogen, can accelerate its autoactivation and cause hereditary or sporadic chronic pancreatitis. Disruption of the locus that encodes cationic trypsinogen in mice (T7) causes loss of expression of the protein, but only partially decreases the severity of secretagogue-induced acute pancreatitis and has no effect on chronic pancreatitis. We investigated whether trypsinogen becomes pathogenic only when its activation is promoted by mutation.. We generated mice with knock-in of the p.K24R mutation (called T7K24R mice), which is analogous to human PRSS1 mutation p.K23R. We gave T7K24R and C57BL/6N (control) mice repeated injections of cerulein to induce pancreatitis. Plasma amylase activity, pancreatic edema, and myeloperoxidase content in pancreas and lungs were quantified. We expressed mutant and full-length forms of PRSS1 in Escherichia coli and compared their autoactivation.. The p.K24R mutation increased autoactivation of T7 5-fold. T7K24R mice developed no spontaneous pancreatitis. T7K24R mice given cerulein injections had increased pancreatic activation of trypsinogen and more edema, infiltration of lung and pancreas by inflammatory cells, and plasma amylase activity compared with control mice given cerulein injections. Injection of cerulein for 2 days induced progressive pancreatitis in T7K24R mice, but not in control mice, with typical features of chronic pancreatitis.. Introduction of a mutation into mice that is analogous to the p.K23R mutation in PRSS1 increases pancreatic activation of trypsinogen during secretagogue-induced pancreatitis. Higher pancreatic activity of trypsin increases the severity of pancreatitis, even though loss of trypsin activity does not prevent pancreatitis in mice.

Topics: Animals; Mice; Mice, Inbred C57BL; Mutation; Pancreas; Pancreatitis; Pancreatitis, Chronic; Secretagogues; Severity of Illness Index; Trypsin; Trypsinogen

Topics: Alcoholism; Animals; Haplotypes; Humans; Mice; Pancreatitis, Chronic; Trypsin; Trypsinogen

Chronic pancreatitis (CP) is a complex inflammatory disorder of the pancreas affecting acinar cells, duct cells, islet cells and inflammatory cells including fibrosis-producing stellate cells. Serum trypsinogen is a biomarkers of acinar cell function.. To define the degree of correlation between low trypsinogen levels as a marker of acinar cell function and variable features of CP.. Serum samples from previously ascertained and well phenotyped case and control subjects from the North American Pancreatitis Study II (NAPS2) were used to measure serum trypsinogen levels in a commercial laboratory. Control samples were used to define normal ranges and compared with levels in CP patients with defined features.. A final cohort of 279 CP patients and 262 controls from the NAPS2 studies were evaluated. In controls trypsinogen had a mean of 34.96 ng/ml and SD = 11.99. Cut-off values for low trypsinogen ranged from <20 to 10 ng/ml and very low trypsinogen at <10 ng/ml. Compared to controls, CP was associated with very low trypsinogen levels (p < 0.0001). Within CP, very low trypsinogen levels correlated with parenchymal loss (pancreatic surgery [p < 0.05]; atrophy with calcifications, [p < 0.001]), EPI (p < 0.01, trend p < 0.001) and diabetes (trend p < 0.01) but not CT-based criteria for fibrosis (pancreatic duct dilation, irregularity, strictures).. Very low serum trypsinogen levels correlate with measures of acinar cell loss including surgical resection, atrophic-calcific CP, diabetes and functional symptoms EPI but not duct morphology criteria. Serum trypsinogen levels correlate with decreased acinar cell function and therefore have biomarker utility clinical management.

Topics: Acinar Cells; Adult; Aged; Atrophy; Biomarkers; Calcinosis; Cohort Studies; Diabetes Complications; Exocrine Pancreatic Insufficiency; Female; Fibrosis; Humans; Male; Middle Aged; Pancreas; Pancreatic Ducts; Pancreatitis, Chronic; Severity of Illness Index; Surveys and Questionnaires; Tomography, X-Ray Computed; Trypsinogen

Topics: Humans; Mutation; Pancreatitis, Chronic; Trypsinogen

Topics: Child; Humans; Mutation; Pancreatitis, Chronic; Pediatrics; Trypsin; Trypsinogen

Topics: Humans; Pancreatitis, Chronic; Trypsin; Trypsinogen

Intra-acinar trypsinogen activation occurs in the earliest stages of pancreatitis and is believed to play important roles in pancreatitis pathogenesis. However, the exact role of intra-acinar trypsin activity in pancreatitis remains elusive. Here, we aimed to examine the specific effects of intra-acinar trypsin activity on the development of pancreatitis using a transgenic mouse model. This transgenic mouse model allowed for the conditional expression of a mutant trypsinogen that can be activated specifically inside pancreatic acinar cells. We found that expression of this active mutated trypsin had no significant effect on triggering spontaneous pancreatitis. Instead, several protective compensatory mechanisms, including SPINK1 and heat shock proteins, were upregulated. Notably, these transgenic mice developed much more severe acute pancreatitis, compared with control mice, when challenged with caerulein. Elevated tissue edema, serum amylase, inflammatory cell infiltration and acinar cell apoptosis were dramatically associated with increased trypsin activity. Furthermore, chronic pathological changes were observed in the pancreas of all transgenic mice, including inflammatory cell infiltration, parenchymal atrophy and cell loss, fibrosis, and fatty replacement. These changes were not observed in control mice treated with caerulein. The alterations in pancreata from transgenic mice mimicked the histological changes common to human chronic pancreatitis. Taken together, we provided in vivo evidence that increased intra-acinar activation of trypsinogen plays an important role in the initiation and progression of both acute and chronic pancreatitis.

Topics: Acinar Cells; Animals; Disease Models, Animal; Mice; Pancreas, Exocrine; Pancreatitis; Pancreatitis, Chronic; Severity of Illness Index; Trypsin; Trypsinogen

Pancreatic ductal adenocarcinoma (PDAC) is a very aggressive tumor with a five-year survival of less than 6%. Chronic pancreatitis (CP), an inflammatory process in of the pancreas, is a strong risk factor for PDAC. Several genetic polymorphisms have been discovered as susceptibility loci for both CP and PDAC. Since CP and PDAC share a consistent number of epidemiologic risk factors, the aim of this study was to investigate whether specific CP risk loci also contribute to PDAC susceptibility. We selected five common SNPs (rs11988997, rs379742, rs10273639, rs2995271 and rs12688220) that were identified as susceptibility markers for CP and analyzed them in 2,914 PDAC cases, 356 CP cases and 5,596 controls retrospectively collected in the context of the international PANDoRA consortium. We found a weak association between the minor allele of the PRSS1-PRSS2-rs10273639 and an increased risk of developing PDAC (OR

Topics: Adenocarcinoma; Adult; Aged; Biomarkers, Tumor; Carcinoma, Pancreatic Ductal; Case-Control Studies; Female; Follow-Up Studies; Humans; Male; Middle Aged; Nuclear Proteins; Pancreatic Neoplasms; Pancreatitis, Chronic; Polymorphism, Single Nucleotide; Prognosis; Retrospective Studies; Risk Factors; Trypsin; Trypsinogen

Inflammatory diseases of the pancreas have no specific therapy. Discovery of the genetic basis of chronic pancreatitis identified the digestive enzyme trypsin as a therapeutic target. Preclinical testing of trypsin inhibition has been hampered by the lack of animal models. Here we report the T7D23A knock-in mouse, which carries a heterozygous p.D23A mutation in mouse cationic trypsinogen (isoform T7). This trypsinogen mutant autoactivates to trypsin 50-fold faster than wild type. T7D23A mice develop spontaneous acute pancreatitis with edema, necrosis and serum amylase elevation at an early age followed by progressive atrophic chronic pancreatitis with acinar cell loss, fibrosis, dilated ducts and adipose replacement. Markedly elevated trypsin activity is apparent at first signs of pancreatitis and persists into later stages of the disease. This remarkable model provides in vivo proof of concept that trypsinogen autoactivation can drive onset and progression of chronic pancreatitis and therapy should be directed against intra-pancreatic trypsin.

Topics: Animals; Enzyme Activation; Female; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Mutation; Pancreas; Pancreatitis; Pancreatitis, Chronic; Trypsin; Trypsinogen

Topics: Chronic Disease; Humans; Mutation; Pancreatitis; Pancreatitis, Chronic; Trypsin; Trypsinogen

Topics: Chronic Disease; Humans; Mutation; Pancreatitis; Pancreatitis, Chronic; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Association of PRSS1-PRSS2 (rs10273639) and CLDN2-MORC4 (rs12688220 and rs7057398) variants with alcohol-related chronic pancreatitis (CP) is established but with nonalcoholic CP is unclear. We addressed this inconsistency using tropical calcific pancreatitis (TCP) as model.. We sequenced 5'-UTR of PRSS1 and genotyped CLDN2-MORC4 variants in 555 patients with TCP and 801 controls and performed association analysis. Gene-gene interaction between PRSS1 and CLDN2-MORC4 variants and with p.Asn34Ser SPINK1 and p.Leu26Val CTSB was also evaluated.. We observed significant association of rs10273639/rs4726576 in PRSS1-PRSS2 (odds ratio [OR] = 0.72; P = 3.50 × 10) and CLDN2-MORC4 variants, rs12688220 (OR = 1.54; P = 1.22 × 10) and rs7057398 (OR = 1.50; P = 1.22 × 10) with TCP. Patients carrying p.Asn34Ser SPINK1 were significantly younger than those with rs4726576 risk genotype (30.0 vs 38.0 years; P = 0.015) and those carrying both were even younger (22.0 years; P = 0.001). Presence of risk allele at rs12688220 in patients carrying p.Asn34Ser SPINK1 delayed the age of onset (32.0 vs 24.0 years; P = 0.013).. Our study establishes strong association of PRSS1-PRSS2 and CLDN2-MORC4 variants with TCP and thus with nonalcoholic CP. These variants independently interact with p.Asn34Ser SPINK1 and influence the age of onset in TCP. However, latter results need to be replicated in other cohorts.

Topics: Alleles; Calcinosis; Claudins; Genetic Predisposition to Disease; Genotype; Humans; Mutation; Nuclear Proteins; Odds Ratio; Pancreatitis, Chronic; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

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.

Topics: Animals; Diabetes Mellitus; Humans; Mutation; National Institute of Diabetes and Digestive and Kidney Diseases (U.S.); Pancreatitis, Chronic; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen; United States

Several genetic risk factors have been identified for non-alcoholic chronic pancreatitis (NACP). A genome-wide association study reported an association of chronic pancreatitis (CP) with variants in PRSS1-PRSS2 (rs10273639; near the gene encoding cationic trypsinogen) and CLDN2-MORC4 loci (rs7057398 in RIPPLY1 and rs12688220 in MORC4). We aimed to refine these findings in a large European cohort.. We studied 3062 patients with alcohol-related CP (ACP) or NACP and 5107 controls. Also, 1559 German patients with alcohol-associated cirrhosis or alcohol dependence were included for comparison. We performed several meta-analyses to examine genotype-phenotype relationships.. Association with ACP was found for rs10273639 (OR, 0.63; 95% CI 0.55 to 0.72). ACP was also associated with variants rs7057398 and rs12688220 in men (OR, 2.26; 95% CI 1.94 to 2.63 and OR, 2.66; 95% CI 2.21 to 3.21, respectively) and in women (OR, 1.57; 95% CI 1.14 to 2.18 and OR 1.71; 95% CI 1.41 to 2.07, respectively). Similar results were obtained when German patients with ACP were compared with those with alcohol-associated cirrhosis or alcohol dependence. In the overall population of patients with NACP, association with rs10273639 was absent (OR, 0.93; 95% CI 0.79 to 1.01), whereas rs7057398 of the X chromosomal single nucleotide polymorphisms was associated with NACP in women only (OR, 1.32; 95% CI 1.15 to 1.51).. The single-nucleotide polymorphisms rs10273639 at the PRSS1-PRSS2 locus and rs7057398 and rs12688220 at the CLDN2-MORC4 locus are associated with CP and strongly associate with ACP, but only rs7057398 with NACP in female patients.

Topics: Case-Control Studies; Claudins; Confidence Intervals; Europe; Female; Genetic Loci; Genetic Predisposition to Disease; Genome-Wide Association Study; Genotype; Humans; Male; Middle Aged; Nuclear Proteins; Odds Ratio; Pancreatitis, Alcoholic; Pancreatitis, Chronic; Polymorphism, Genetic; Polymorphism, Single Nucleotide; Reference Values; Sex Factors; Survival Analysis; Trypsin; Trypsinogen

Human chymotrypsin C (CTRC) protects against pancreatitis by degrading trypsinogen and thereby curtailing harmful intra-pancreatic trypsinogen activation. Loss-of-function mutations in CTRC increase the risk for chronic pancreatitis. Here we describe functional analysis of eight previously uncharacterized natural CTRC variants tested for potential defects in secretion, proteolytic stability, and catalytic activity. We found that all variants were secreted from transfected cells normally, and none suffered proteolytic degradation by trypsin. Five variants had normal enzymatic activity, whereas variant p.R29Q was catalytically inactive due to loss of activation by trypsin and variant p.S239C exhibited impaired activity possibly caused by disulfide mispairing. Surprisingly, variant p.G214R had increased activity on a small chromogenic peptide substrate but was markedly defective in cleaving bovine β-casein or the natural CTRC substrates human cationic trypsinogen and procarboxypeptidase A1. Mutation p.G214R is analogous to the evolutionary mutation in human mesotrypsin, which rendered this trypsin isoform resistant to proteinaceous inhibitors and conferred its ability to cleave these inhibitors. Similarly to the mesotrypsin phenotype, CTRC variant p.G214R was inhibited poorly by eglin C, ecotin, or a CTRC-specific variant of SGPI-2, and it readily cleaved the reactive-site peptide bonds in eglin C and ecotin. We conclude that CTRC variants p.R29Q, p.G214R, and p.S239C are risk factors for chronic pancreatitis. Furthermore, the mesotrypsin-like CTRC variant highlights how the same natural mutation in homologous pancreatic serine proteases can evolve a new physiological role or lead to pathology, determined by the biological context of protease function.

Topics: Amino Acid Sequence; Animals; Caseins; Cattle; Chymotrypsin; Genetic Variation; HEK293 Cells; Humans; Models, Molecular; Molecular Sequence Data; Mutation; Pancreatitis, Chronic; Protein Conformation; Recombinant Proteins; Risk Factors; Substrate Specificity; Trypsin; Trypsinogen

The pathogenesis of chronic pancreatitis (CP) is poorly understood. Endoplasmic reticulum (ER) stress has now been recognized as a pathogenic event in many chronic diseases. However, ER stress has not been studied in CP, although pancreatic acinar cells seem to be especially vulnerable to ER dysfunction because of their dependence on high ER volume and functionality. Here, we aim to investigate ER stress in CP, study its pathogenesis in relation to trypsinogen activation (widely regarded as the key event of pancreatitis), and explore its mechanism, time course, and downstream consequences during pancreatic injury. CP was induced in mice by repeated episodes of acute pancreatitis (AP) based on caerulein hyperstimulation. ER stress leads to activation of unfolded protein response components that were measured in CP and AP. We show sustained up-regulation of unfolded protein response components ATF4, CHOP, GRP78, and XBP1 in CP. Overexpression of GRP78 and ATF4 in human CP confirmed the experimental findings. We used novel trypsinogen-7 knock-out mice (T(-/-)), which lack intra-acinar trypsinogen activation, to clarify the relationship of ER stress to intra-acinar trypsinogen activation in pancreatic injury. Comparable activation of ER stress was seen in wild type and T(-/-) mice. Induction of ER stress occurred through pathologic calcium signaling very early in the course of pancreatic injury. Our results establish that ER stress is chronically activated in CP and is induced early in pancreatic injury through pathologic calcium signaling independent of trypsinogen activation. ER stress may be an important pathogenic mechanism in pancreatitis that needs to be explored in future studies.

Topics: Acinar Cells; Activating Transcription Factor 4; Animals; Endoplasmic Reticulum Chaperone BiP; Endoplasmic Reticulum Stress; Female; Heat-Shock Proteins; Humans; Male; Mice; Pancreatitis, Chronic; Trypsinogen; Unfolded Protein Response

Mutations in human cationic trypsinogen cause hereditary pancreatitis by altering its proteolytic regulation of activation and degradation by chymotrypsin C (CTRC). CTRC stimulates trypsinogen autoactivation by processing the activation peptide to a shorter form, but also promotes degradation by cleaving the calcium-binding loop in trypsinogen. Mutations render trypsinogen resistant to CTRC-mediated degradation and/or increase processing of the activation peptide by CTRC. Here we demonstrate that the activation peptide mutations D19A, D22G, K23R and K23_I24insIDK robustly increased the rate of trypsinogen autoactivation, both in the presence and absence of CTRC. Degradation of the mutants by CTRC was unchanged, and processing of the activation peptide was increased fourfold in the D19A mutant only. Surprisingly, however, this increased processing had only a minimal effect on autoactivation. The tetra-aspartate motif in the trypsinogen activation peptide binds calcium (KD of ~ 1.6 mM), which stimulates autoactivation. Unexpectedly, calcium binding was not compromised by any of the activation peptide mutations. Despite normal binding, autoactivation of mutants D22G and K23_I24insIDK was not stimulated by calcium. Finally, the activation peptide mutants exhibited reduced secretion from transfected cells, and secreted trypsinogen levels were inversely proportional with autoactivation rates. We conclude that D19A, D22G, K23R and K23_I24insIDK form a mechanistically distinct subset of hereditary pancreatitis-associated mutations that exert their effect primarily through direct stimulation of autoactivation, independently of CTRC. The potentially severe clinical impact of the markedly increased autoactivation is offset by diminished secretion, resulting in a clinical phenotype that is indistinguishable from typical hereditary pancreatitis.

Topics: Calcium; Chymotrypsin; Enzyme Activation; HEK293 Cells; Humans; Mutation, Missense; Pancreatitis, Chronic; Peptide Fragments; Protein Binding; Proteolysis; Trypsin; Trypsinogen

A frequently used experimental model of chronic pancreatitis (CP) recapitulating human disease is repeated injection of cerulein into mice. C57BL/6 is the most commonly used inbred mouse strain for biomedical research, but widespread demand has led to generation of several substrains with subtly different phenotypes. In this study, two common substrains, C57BL/6J and C57BL/6NHsd, exhibited different degrees of CP, with C57BL/6J being more susceptible to repetitive cerulein-induced CP as assessed by pancreatic atrophy, pancreatic morphological changes, and fibrosis. We hypothesized that the deficiency of nicotinamide nucleotide transhydrogenase (NNT) protein in C57BL/6J is responsible for the more severe C57BL/6J phenotype but the parameters of CP in NNT-expressing transgenic mice generated on a C57BL6/J background do not differ with those of wild-type C57BL/6J. The highly similar genetic backgrounds but different CP phenotypes of these two substrains presents a unique opportunity to discover genes important in pathogenesis of CP. We therefore performed whole mouse genome Affymetrix microarray analysis of pancreatic gene expression of C57BL/6J and C57BL/6NHsd before and after induction of CP. Genes with differentially regulated expression between the two substrains that might be candidates in CP progression included Mmp7, Pcolce2, Itih4, Wdfy1, and Vtn. We also identified several genes associated with development of CP in both substrains, including RIKEN cDNA 1810009J06 gene (trypsinogen 5), Ccl8, and Ccl6.

Topics: Animals; Cell Separation; Ceruletide; Chemokine CCL8; Chemokines, CC; Collagen; Disease Progression; Fibrosis; Gene Expression Profiling; Gene Expression Regulation; Genetic Association Studies; Humans; Mice; Mice, Inbred C57BL; NADP Transhydrogenases; Pancreas; Pancreatic Stellate Cells; Pancreatitis, Chronic; Risk Factors; RNA, Messenger; Trypsinogen

Premature activation of trypsinogen activation can cause pancreatic injury and has been associated with chronic pancreatitis (CP). Mice that lack intra-acinar activation of trypsinogen, such as trypsinogen-7-null (T(-/-)) and cathepsin B-null (CB(-/-)) mice, have been used to study trypsin-independent processes of CP development. We compared histologic features and inflammatory responses of pancreatic tissues from these mice with those from wild-type mice after the development of CP.. CP was induced in wild-type, T(-/-), and CB(-/-) mice by twice-weekly induction of acute pancreatitis for 10 weeks; acute pancreatitis was induced by hourly intraperitoneal injections of cerulein (50 μg/kg × 6). Pancreatic samples were collected and evaluated by histologic and immunohistochemical analyses. Normal human pancreas samples, obtained from the islet transplant program at the University of Minnesota, were used as controls and CP samples were obtained from surgical resections.. Compared with pancreatic tissues from wild-type mice, those from T(-/-) and CB(-/-) mice had similar levels of atrophy, histomorphologic features of CP, and chronic inflammation. All samples had comparable intra-acinar activation of nuclear factor (NF)-κB, a transcription factor that regulates the inflammatory response, immediately after injection of cerulein. Pancreatic tissue samples from patients with CP had increased activation of NF-κB (based on nuclear translocation of p65 in acinar cells) compared with controls.. Induction of CP in mice by cerulein injection does not require intra-acinar activation of trypsinogen. Pancreatic acinar cells of patients with CP have increased levels of NF-κB activation compared with controls; regulation of the inflammatory response by this transcription factor might be involved in the pathogenesis of CP.

Topics: Acinar Cells; Animals; Cells, Cultured; Ceruletide; Immunohistochemistry; Mice; Mice, Inbred C57BL; Pancreas; Pancreatitis, Chronic; Trypsinogen

The effects of trypsin on pancreatic ductal epithelial cells (PDECs) vary among species and depend on the localization of proteinase-activated receptor 2 (PAR-2). We compared PAR-2 localization in human and guinea-pig PDECs, and used isolated guinea pig ducts to study the effects of trypsin and a PAR-2 agonist on bicarbonate secretion.. PAR-2 localization was analyzed by immunohistochemistry in guinea pig and human pancreatic tissue samples (from 15 patients with chronic pancreatitis and 15 without pancreatic disease). Functionally, guinea pig PDECs were studied by microperfusion of isolated ducts, measurements of intracellular pH and intracellular Ca(2+) concentration, and patch clamp analysis. The effect of pH on trypsinogen autoactivation was assessed using recombinant human cationic trypsinogen.. PAR-2 localized to the apical membrane of human and guinea pig PDECs. Trypsin increased intracellular Ca(2+) concentration and intracellular pH and inhibited secretion of bicarbonate by the luminal anion exchanger and the cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel. Autoactivation of human cationic trypsinogen accelerated when the pH was reduced from 8.5 to 6.0. PAR-2 expression was strongly down-regulated, at transcriptional and protein levels, in the ducts of patients with chronic pancreatitis, consistent with increased activity of intraductal trypsin. Importantly, in PAR-2 knockout mice, the effects of trypsin were markedly reduced.. Trypsin reduces pancreatic ductal bicarbonate secretion via PAR-2-dependent inhibition of the apical anion exchanger and the CFTR Cl(-) channel. This could contribute to the development of chronic pancreatitis by decreasing luminal pH and promoting premature activation of trypsinogen in the pancreatic ducts.

Topics: Animals; Anion Exchange Resins; Bicarbonates; Cystic Fibrosis Transmembrane Conductance Regulator; Enzyme Activation; Epithelial Cells; Guinea Pigs; Humans; Immunohistochemistry; Mice; Mice, Inbred C57BL; Mice, Knockout; Pancreatic Ducts; Pancreatitis, Chronic; Real-Time Polymerase Chain Reaction; Receptor, PAR-2; Reverse Transcriptase Polymerase Chain Reaction; Trypsin; Trypsinogen

Pancreatic juice is a potential source of proteins associated with pancreatic cancer (PC) due to the proximity of ducts to tumor tissue. Therefore, screening of proteins in pancreatic juice from PC patients may identify new PC biomarkers. We analyzed pancreatic juice from patients with pancreatic diseases including PC, chronic pancreatitis (CP) and simple choledocholithiasis (CDS) by 2-DE. Protein spots from PC patients that changed >2-fold compared with both CP and CDS were selected and identified by mass spectrometry (MS). mRNA levels were measured by QRT-PCR in PC cell lines, PC tissues and adjacent pancreatic normal (PN) tissues. Relationships between mRNA levels in PC tissues and their clinical characteristics and promoter methylation were analyzed in PC cell lines and tissues. We found that four proteins were significantly changed in PC compared to CP and simple CDS. Two proteins were up-regulated, serine proteinase-2 (PRSS2) preproprotein and pancreatic lipase-related protein-1 (PLRP1), and two proteins were down-regulated, chymotrypsinogen B (CTRB) precursor and elastase 3B (ELA3B) preproprotein. In all PC cell lines, PRSS 2 mRNA levels were elevated, while PLRP 1 mRNA was detected in 4/5 cell lines. ELA3B mRNA was undetectable in all cell lines, but CTRB mRNA was detected in 2/5 cell lines. In PC tissues compared to PN, levels of PRSS2 mRNA were significantly higher, ELA3B significantly lower, and PLRP1 and CTRB not significantly different. Elevated PRSS2 mRNA levels correlated with high T stage. The ELA3B gene promoter had higher methylation in PC cell lines and tissues compared with PN tissues, and correlated with low ELA3B gene expression. In conclusion, comparative proteomic analysis of pancreatic juice from PC patients is a powerful method to find new PC biomarkers. Hyperexpression of the PRSS2 gene and hypermethylation of ELA3B gene promoter were associated with PC, raising the possibility of their application as new biomarkers in PC diagnosis and screening.

Topics: Aged; Biomarkers, Tumor; Carcinoma, Pancreatic Ductal; Choledocholithiasis; Chymotrypsin; DNA Methylation; Electrophoresis, Gel, Two-Dimensional; Female; Humans; Intracellular Signaling Peptides and Proteins; Male; Middle Aged; Nuclear Proteins; Pancreas; Pancreatic Elastase; Pancreatic Juice; Pancreatic Neoplasms; Pancreatitis, Chronic; Prognosis; Promoter Regions, Genetic; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Trypsin; Trypsinogen; Tumor Cells, Cultured

Human trypsinogens are post-translationally sulfated on Tyr154 by the Golgi resident enzyme tyrosylprotein sulfotransferase-2 (TPST2). Tyrosine sulfation stimulates the autoactivation of human cationic trypsinogen. Because increased trypsinogen autoactivation has been implicated as a pathogenic mechanism in chronic pancreatitis, we hypothesized that genetic variants of TPST2 might alter the risk for the disease.. We sequenced the 4 protein-coding exons and the adjacent intronic sequences of TPST2 in 151 subjects with chronic pancreatitis and in 169 healthy controls. The functional effect of TPST2 variants on trypsinogen sulfation was analyzed in transfected HEK 293T cells.. We detected 10 common polymorphic variants, including 6 synonymous variants and 4 intronic variants, with similar frequencies in patients and controls. None of the 8 common haplotypes reconstructed from the frequent variants showed an association with chronic pancreatitis. In addition, we identified 5 rare TPST2 variants, which included 3 synonymous alterations, the c.458G>A (p.R153H) nonsynonymous variant and the c.-9C>T variant in the 5' untranslated region. The p.R153H variant was found in a family with hereditary pancreatitis; however, it did not segregate with the disease. In functional assays, both the p.R153H and c.-9C>T TPST2 variants catalyzed trypsinogen sulfation as well as wild-type TPST2.. Genetic variants of human TPST2 exert no influence on the risk of chronic pancreatitis.

Topics: Adult; Aged; Aged, 80 and over; Base Sequence; Female; Humans; Male; Membrane Proteins; Middle Aged; Pancreatitis, Chronic; Pedigree; Polymorphism, Genetic; Sulfotransferases; Trypsinogen

The prevalence and natural history of hereditary pancreatitis (HP) remain poorly documented. The aims of this study were to assess genetic, epidemiological, clinical and morphological characteristics of HP in an extensive national survey.. A cohort comprising all HP patients was constituted by contacting all gastroenterologists and paediatricians (response rate 84%) and genetics laboratories (response rate 100%) in France (60,200,000 inhabitants). Inclusion criteria were the presence of mutation in the cationic trypsingen gene (PRSS1 gene), or chronic pancreatitis in at least two first-degree relatives, or three second-degree relatives, in the absence of precipitating factors for pancreatitis.. 78 families and 200 patients were included (181 alive, 6673 person-years, males 53%, alcoholism 5%, smoking 34%). The prevalence was 0.3/100,000 inhabitants. PRSS1 mutations were detected in 68% (R122H 78%, N29I 12%, others 10%). Penetrance was 93%. Median age at first symptom, diagnosis and date of last news, were 10 (range 1-73), 19 (1-80) and 30 (1-84) years, respectively. HP was responsible for pancreatic pain (83%), acute pancreatitis (69%), pseudocysts (23%), cholestasis (3%), pancreatic calcifications (61%), exocrine pancreatic insufficiency (34%, median age of occurrence 29 years), diabetes mellitus (26%, median age of occurrence 38 years) and pancreatic adenocarcinoma (5%, median age 55 years). No differences in clinical and morphological data according to genetic status were observed. 19 patients died, including 10 directly from HP (8 from pancreatic adenocarcinoma).. The prevalence of HP in France is at least 0.3/100,000. PRSS1 gene mutations are found in 2/3 with a 93% penetrance. Mutation type is not correlated with clinical/morphological expression. Pancreatic adenocarcinoma is the cause of nearly half the deaths.

Topics: Adenocarcinoma; Adolescent; Adult; Age Distribution; Age of Onset; Aged; Aged, 80 and over; Child; Child, Preschool; Epidemiologic Methods; Exocrine Pancreatic Insufficiency; Female; France; Genotype; Humans; Infant; Male; Middle Aged; Mutation; Pancreatic Neoplasms; Pancreatitis, Chronic; Penetrance; Phenotype; Trypsin; Trypsinogen; Young Adult

There is a concept that pancreatitis results from an imbalance of proteases and their inhibitors within the pancreatic parenchyma. It has been recently shown that a loss-of-function variant, c.571G>A (p.G191R), in the anionic trypsinogen (PRSS2) gene protects against chronic pancreatitis in European populations. Here we examined the association of the p.G191R variant with pancreatic disorders in Japan.. Genomic DNA was prepared from 378 healthy controls and 604 patients with pancreatic disorders (241 patients with chronic pancreatitis, 174 with acute pancreatitis, and 189 with pancreatic neoplasm). Mutational analysis of the PRSS2 gene was performed by polymerase chain reaction-restriction fragment length polymorphism and direct sequencing.. The heterozygous p.G191R variant was found in three of 241 (1.2%) patients with chronic pancreatitis, in seven of 174 (4.0%) patients with acute pancreatitis, and in 12 of 189 (6.3%) patients with pancreatic neoplasm. The p.G191R variant was found in 25 (two were homozygous and 23 were heterozygous) of 378 (6.6%) healthy controls. The p.G191R frequency in patients with chronic pancreatitis was lower than that in healthy controls (p = 0.001; odds ratio (OR) 0.178; 95% confidence interval (CI) = 0.057 to 0.561). The p.G191R frequency was lower in patients with alcoholic (0.9%; p = 0.015; OR, 0.132; 95% CI, 0.022 to 0.779) and idiopathic (1.0%; p = 0.025; OR, 0.144; 95% CI, 0.025 to 0.851) chronic pancreatitis than that in healthy controls. There were no statistical differences in the p.G191R frequency between healthy controls and patients with acute pancreatitis or with pancreatic neoplasm. Patients with alcoholic acute pancreatitis (n = 59) had no variant carrier, and the p.G191R frequency was lower than that in healthy controls (p = 0.035).. The p.G191R variant protected against alcoholic and idiopathic chronic pancreatitis as well as alcoholic acute pancreatitis in Japan.

Topics: Adenocarcinoma; Adult; Aged; Alcohol Drinking; Case-Control Studies; DNA Mutational Analysis; Female; Gene Frequency; Genotype; Heterozygote; Homozygote; Humans; Japan; Male; Middle Aged; Multivariate Analysis; Mutation; Odds Ratio; Pancreatic Neoplasms; Pancreatitis; Pancreatitis, Acute Necrotizing; Pancreatitis, Chronic; Trypsin; Trypsinogen

Tropical calcific pancreatitis (TCP) refers to a type of idiopathic pancreatitis prevalent in Asia. The trypsin inhibitor (SPINK1) N34S variant partially explains the genetic susceptibility to TCP. As anionic trypsinogen (PRSS2) G191R protects against chronic pancreatitis in Europeans, we investigated whether this variant protects from TCP in Indians.. We enrolled 174 patients and 794 controls from two Indian tertiary care referral hospitals. We analyzed PRSS2 and SPINK1 variants by melting curve analysis, allele-specific discrimination assay, and sequencing.. G191R was detected in 1 TCP patient (0.6%) compared to 13 controls (1.6%; OR 0.27, 95% CI 0.03-2.1; p = 0.33). SPINK1 N34S was enriched in the TCP population 67/174 (38.5%) compared to controls 10/234 (4.3%; OR 14, 95% CI 6.9-28.3; p < 0.001).. G191R PRSS2 is a rare allele in the Indian population and the data suggest a nonsignificant trend towards a protective effect. N34S SPINK1 represents the major genetic risk factor in TCP.

Topics: Adult; Amino Acid Substitution; Calcinosis; Carrier Proteins; Female; Genetic Predisposition to Disease; Genetic Variation; Heterozygote; Homozygote; Humans; India; Male; Pancreatitis, Chronic; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Tropical calcific pancreatitis (TCP) is a relatively common form of chronic pancreatitis in parts of Asia and Africa. The SPINK1 variant p.N34S is strongly associated with TCP, but other genetic factors remain to be defined. Chymotrypsinogen C (CTRC) degrades trypsinogen and loss-of-function variants have been found in European patients with chronic pancreatitis. Preliminary data indicate that CTRC might increase the risk for TCP.. We selected 150 Indian TCP patients and 150 Indian controls to perform mutational screening of the complete coding region of CTRC and exon 3 of SPINK1. We performed in-silico analysis and functional studies of novel CTRC variants.. We identified eight variants among this sample. Three were synonymous and c.180 C>T was significantly enriched in patients (odds ratio=2.09; 95% confidence interval=1.19-3.67; P=0.03). We identified a novel nonsynonymous CTRC (p.G61R) variant in one of 146 patients (0.7%), but absent from controls. In-silico analysis showed that this variant affected a conserved residue, and functional analysis showed that p.G61R results in a complete loss of CTRC secretion from transiently transfected human embryonic kidney 293T cells. SPINK1 p.N34S was present in 31.8% of patients compared with 4.7% in controls, there was no significant cosegregation with CTRC variants.. The contribution of CTRC variants to TCP is relatively small, but the identification of novel loss-of-function variants (p.G61R) underscores the importance of the trypsinogen pathway in causing TCP.

Topics: Adolescent; Adult; Calcinosis; Carrier Proteins; Case-Control Studies; Child; Child, Preschool; Chymotrypsinogen; Female; Genetic Predisposition to Disease; Genetic Variation; Humans; India; Male; Middle Aged; Pancreatitis, Chronic; Serine Endopeptidases; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen; Young Adult

Topics: Case-Control Studies; Gene Expression; Heterozygote; Humans; India; Japan; Pancreatic Juice; Pancreatitis, Chronic; Polymorphism, Genetic; Trypsin; Trypsinogen

Topics: Adult; Age of Onset; Asian People; China; Genetic Predisposition to Disease; Humans; Mutation; Pancreatitis, Chronic; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

One of the causes of chronic pancreatitis is the duplication and triplication of a approximately 605 kb segment containing the trypsinogen locus. Employing array-comparative genomic hybridization, we fully characterized the triplication copy number mutation (CNM) and found it to be part of a complex rearrangement that also contains a triplicated approximately 137 kb segment and 21 bp sequence tract. This triplication allele therefore constitutes a gain of two tandemly arranged composite duplication blocks, each comprising a copy of the approximately 605 kb segment, a copy of the inverted approximately 137 kb segment and a copy of the inverted 21 bp sequence tract. As such, it represents the first characterization of a human complex triplication CNM at the DNA sequence level. All triplications and duplications identified were found to arise from a common founder chromosome. A two-step process is proposed for the generation of this highly unusual triplication CNM. Thus, the first composite duplication block is envisaged to have been generated by break-induced serial replication slippage during mitosis. This duplication would have provided the sequence homology required to promote non-allelic homologous recombination (NAHR) during meiosis which would then, in a second step, have generated the complex triplication allele. Our data provide support for the view that many human germline copy number variants arise through replication-based mechanisms during the premeiotic mitotic divisions of germ cells. The low copy repeats thereby generated could then serve to promote NAHR during meiosis, giving rise to amplified DNA sequences which would themselves predispose to further recombinational events during both mitosis and meiosis.

Topics: Base Sequence; DNA Replication; Female; Gene Dosage; Gene Duplication; Humans; Male; Molecular Sequence Data; Pancreatitis, Chronic; Recombination, Genetic; Trypsinogen

Chronic pancreatitis is an inflammatory disease followed by structural alterations--inflammation, fibrosis and acinar atrophy--pain emergence, exocrine and endocrine pancreatic insufficiency, severe alteration of quality of life. The pathogenetic mechanisms characteristic to this disease are not thoroughly known, but the identification of some genetic and autoimmune factors in certain entities has elucidated several pathogenetic links. The etiologic risk factors for chronic pancreatitis may associate each other and may cause different evolutions to the disease. By tracing out the risk factors and their typical working mechanisms, further pathogenetic treatments may occur, taking place precociously and preventing the evolution of the disease towards exocrine and endocrine pancreatic insufficiency.

Topics: Alcoholism; Autoimmune Diseases; Carrier Proteins; Cystic Fibrosis Transmembrane Conductance Regulator; Humans; Mutation; Pancreatitis, Chronic; Risk Factors; Severity of Illness Index; Smoking; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

The understanding of genetic risk factors for chronic pancreatitis increased in the last decade with the discovery of mutations in the cationic trypsinogen gene (PRSS1). The first mutation was detected at the R122 autocleavage site of the protein (R122H) and subsequently two other mutations in this region, R122C and V123M, were described that resulted in a similar phenotype of hereditary pancreatitis. This study reports a novel A121T mutation within this region and characterises the resulting molecular properties at the autocleavage site.. Blood samples of a PRSS1 A121T carrier family were analysed for PRSS1 mutations using melting point curve analysis, restriction endonucleases and DNA sequencing. Conformation dependent properties of the mutated sequence were analysed by molecular modelling. The autodegradation kinetic of the mutated trypsin sequence was measured by a novel fluorescence resonance energy transfer (FRET) assay using designed 11 amino acid peptides from PRSS1 aa 118-aa 127 containing the trypsin cleavage site at aa 122 coupled to a Dabcyl/EDANS FRET system. The kinetic of tryptic peptide cleavage was measured in a fluorescence enzyme linked immunosorbent assay (ELISA) reader.. DNA sequencing revealed a novel G to A transition at position 133279 of the published genomic sequence (#U66061 GenBank). The mutation results in an amino acid substitution of alanine by threonine at position 121 (A121T) of the cationic trypsinogen. Four additional mutation carriers could be identified among the relatives while only the first patient developed chronic pancreatitis. Molecular modelling of PRSS1 A121T revealed a change in the bond pattern between the R122 region and the calcium binding loop, whereas FRET assays showed an increased trypsin cleavage rate with a reaction kinetic elevated by more than 80%.. The novel PRSS1 A121T mutation highlights the surface exposed region PRSS1 A121-R122-V123 as a hotspot for hereditary pancreatitis associated trypsinogen mutations. Molecular modelling and FRET assays provide evidence for an A121T mutation dependent increase in susceptibility to trypsin digestion at the R122 cleavage site suggesting an enhanced autodegradation and a loss-of-function at the autocleavage site.

Topics: Amino Acid Substitution; Female; Fluorescence Resonance Energy Transfer; Genetic Predisposition to Disease; Humans; Male; Middle Aged; Models, Molecular; Molecular Sequence Data; Mutation; Pancreatitis, Chronic; Pedigree; Penetrance; Trypsinogen

Chronic pancreatitis shows alterations in the trypsinogen gene (protease serine 1, PRSS1) in some individuals. The conversion of trypsinogen to trypsin in the pancreas is believed to be one of the causes of pancreatitis. This study was to identify the mutation of the PRSS1 gene in a Chinese patient with chronic pancreatitis and to analyze the clinical features of the disease.. In 6 patients with chronic pancreatitis and 120 normal controls, PRSS1 genes were amplified by the polymerase chain reaction and the products were analyzed by sequencing.. Multisite mutations of PRSS1 were found in a patient with chronic pancreatitis. C to A mutation occurred in exon 3 of PRSS1, and T to A mutation in the same exon. These mutations were not found in normal controls or the patients with chronic pancreatitis.. These are novel mutations in PRSS1.

Topics: Adult; China; DNA; Female; Genetic Predisposition to Disease; Humans; Mutation; Pancreatitis, Chronic; Polymerase Chain Reaction; Polymorphism, Genetic; Trypsin; Trypsinogen

The R122H mutation represents the most common point mutation of the cationic trypsinogen gene (PRSS1) in patients with hereditary pancreatitis (HP; Online Mendelian inheritance in man [OMIM] 167800), a rare variety of chronic pancreatitis. We identified a large number of HP families carrying this mutation in a confined region of Northern Germany within a 100-km radius. This apparent clustering could be due to the inheritance from a common ancestor (founder effect).. To address this question, we genotyped SNPs in close vicinity of the PRSS1 locus and determined common haplotypes.. In members from 10 unrelated HP families (all R122H-positive), we found 7 different haplotypes to segregate with the R122H mutation.. This virtually excludes a founder effect and suggests the presence of a mutational hot spot in codon 122 of the PRSS1 gene. An ascertainment bias of a large-volume referral center may have contributed to the locally increased detection of HP cases.

Topics: Cholangiopancreatography, Endoscopic Retrograde; Cluster Analysis; DNA; Female; Gene Frequency; Genetic Predisposition to Disease; Germany; Haplotypes; Humans; Incidence; Male; Mutation; Pancreatitis, Chronic; Sequence Analysis, DNA; Tomography, X-Ray Computed; Trypsin; Trypsinogen

Hereditary pancreatitis (HP) is a rare cause of chronic pancreatitis (CP; 1%) and more than 25 mutations in the PRSS1 gene have been detected. HP patients with the p.R122H mutation have a 35% lifetime risk of developing pancreatic cancer, but the oncogenetic process remains unknown. We have investigated the histopathological features and frequency of BRAF and KRAS2 mutations in 2 patients with PRSS1 mutations (p.A121T, p.R122H) and patients with CP (n = 11).. Pancreatic tissue was stained with hematoxylin-eosin and examined by light microscopy. Mutational analysis of the BRAF (exon 5, 11) and KRAS2 (exon 1) genes was performed using PCR and direct DNA sequencing.. Histopathological features revealed similar results in both patients, pancreata showed strong fibrosis and ducts with signs of distortion, irregular size and noticeable dilatations. We identified one BRAF mutation (p.V600E) in the p.R122H patient and two KRAS2 (p.G12D; p.G12C) mutations in CP controls.. Our results sustain the knowledge about the clinical phenotype of patients with PRSS1 mutations who have a high risk of pancreatic cancer. Whether the histopathological picture or the BRAF mutation is specific for patients with PRSS1 mutations or plays a specific role in the tumorigenesis of patients with HP needs to be further evaluated.

Topics: Adult; DNA Mutational Analysis; Genotype; Humans; Male; Middle Aged; Mutation; Pancreas; Pancreatitis, Chronic; Phenotype; Proto-Oncogene Proteins; Proto-Oncogene Proteins B-raf; Proto-Oncogene Proteins p21(ras); ras Proteins; Trypsin; Trypsinogen

Cystic fibrosis transmembrane conductance regulator (CFTR), cationic trypsinogen gene (PRSS1), and serine protease inhibitor kazal type 1 (SPINK1) gene mutations have been associated with chronic pancreatitis (CP). The aim of this study was to compare clinical and radiological findings in sporadic CP with (CPgm) and without (CPwt) gene mutations.. Data from patients observed between 2001 and 2006 were collected. All patients were tested for 25 CFTR gene mutations, for R122H and N29I on the PRSS1 gene, and for N34S mutation on the SPINK1 gene.. We found 34 (17.2%) of 198 patients with CPgm, 23 (11.6%) of them on the CFTR gene, 11 (5.6%) on the SPINK1, and none on the PRSS1 gene. The age at clinical onset was younger in CPgm (36.2 +/- 17.2 years) than in CPwt (44 +/- 12.6 years; P = 0.005). There were more heavy drinkers among CPwt (33%) than among CPgm (9%; P = 0.003), and the same applied to smokers (69% vs 33%, respectively; P < 0.0001). In CPgm group, the onset of pancreatic calcifications was observed more frequently in drinkers and/or smokers. Exocrine and endocrine insufficiency occurred less frequently and later in CPgm than in CPwt patients.. Clinical and radiological outcome differ in CPgm compared with CPwt. Alcohol, even in small quantities, and cigarette smoking influence the onset of pancreatic calcifications.

Topics: Adult; Age Factors; Alcohol Drinking; Carrier Proteins; Cystic Fibrosis Transmembrane Conductance Regulator; Female; Genetic Predisposition to Disease; Humans; Male; Middle Aged; Mutation; Pancreatitis, Chronic; Prospective Studies; Radiography; Risk Factors; Smoking; Time Factors; Treatment Outcome; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen; Young Adult

We have recently reported that the triplication of a approximately 605 kilobase segment containing the PRSS1 (encoding cationic trypsinogen) and PRSS2 (encoding anionic trypsinogen) genes causes hereditary pancreatitis. Here we went further to investigate whether this copy number mutation could account for some unidentified French white patients with idiopathic chronic pancreatitis (ICP) or familial chronic pancreatitis (FCP) as well as Indian patients with tropical calcific pancreatitis (TCP).. Patients and controls were screened by means of previously described quantitative fluorescent multiplex polymerase chain reaction and/or genotyping of the microsatellite marker rs3222967.. The approximately 605 kilobase triplication and a novel duplication (confirmed by fluorescence in situ hybridization) of the trypsinogen locus were detected in 10 and 2 of 202 ICP patients, respectively (age of disease onset, 20 years. However, the 2 trypsinogen copy number mutations were observed in neither 103 FCP patients nor 268 Indian TCP patients.. Our findings revealed the molecular basis of 6% of the young ICP patients and further demonstrated that chronic pancreatitis is a genomic disorder. Our findings also add to the mounting evidence showing that trypsinogen gene mutations do not appear to play an important role in the pathogenesis of TCP in the Indian population. Finally, a dividend of this study is that we have provided convincing evidence to show that all 5 previously described copy number variations involving PRSS1 or/and PRSS2 are artifacts.

Topics: Adolescent; Adult; Case-Control Studies; Child; Female; France; Gene Dosage; Genetic Markers; Humans; In Situ Hybridization, Fluorescence; India; Male; Middle Aged; Mutation; Pancreatitis, Chronic; Polymerase Chain Reaction; Trypsinogen; White People

Mutations in the cationic trypsinogen gene (PRSS1) have been detected in patients with hereditary pancreatitis (HP). This study investigated the prevalence of the R122H (c.365 G > A), A121T (c.361 G > A) and D162D (c.488 C > T) mutations or polymorphisms in the common, non-hereditary forms of chronic pancreatitis and in an HP family.. DNA was prepared from blood samples of 54 patients with chronic pancreatitis (35 alcoholic, 17 idiopathic and 2 hereditary) and 120 normal controls. The PRSS1 genes were amplified by polymerase chain reaction (PCR) and their products were analyzed by sequencing and related clinical data were also collected.. A new polymorphism (c.488 C > T) of PRSS1 was found in 25 patients with chronic pancreatitis (including one affected member of the HP family) and six members of the normal controls. The C/T genotype was significantly increased in chronic pancreatitis (OR: 16.379, 95% CI: 5.7522 - 52.3663), the frequency of c.488 C > T change was in according with the Hardy-Weinberg equilibrium, but it doesn't affect the clinical phenotype. The commonly reported change of R122H (c.365 G > A) was not detected in any of the study subjects. c.361 G > A was found in 2 affected members and one unaffected carrier in an HP family. One of the affected members of an HP family had c.361 G > A mutation and polymorphism (c.488 C > T) in the PRSS1 gene at the same time. The patient's clinical values (C3, C4, CA19-9 and HbA1c) were higher than those of the other patients with chronic pancreatitis. The two patients with HP developed diabetes mellitus and their father died with pancreatic cancer.. A new polymorphism (c.488 C > T) in the PRSS1 gene is associated with chronic pancreatitis, but it did not affect the clinical phenotype while the A121T (c.361 G > A) mutation in the gene shows a significant correlation in the patients with HP.

Topics: Female; Humans; Male; Mutation; Pancreatitis; Pancreatitis, Chronic; Polymorphism, Genetic; Trypsin; Trypsinogen

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Alleles; Amino Acid Substitution; Base Sequence; Case-Control Studies; Child; DNA Primers; Female; Gene Frequency; Heterozygote; Humans; Hungary; Male; Middle Aged; Pancreatitis, Chronic; Polymorphism, Single Nucleotide; Trypsin; Trypsinogen

To assess a point-of-care (POC) urine trypsinogen (UT) test for the diagnosis of pancreatitis in the emergency department (ED).. This was a prospective cohort study of a convenience sample of patients presenting to the ED with abdominal pain or symptoms suggestive of pancreatitis. A 3-minute POC UT test (Actim Pancreatitis; Medix Biochemica, Kauniainen, Finland) was compared with plasma lipase and amylase measurements, imaging results when performed, and final discharge diagnoses. The criterion standard was a final discharge diagnosis of acute pancreatitis.. Of 191 patients included in this study, 17 patients were diagnosed with either acute or acute-on-chronic pancreatitis. The sensitivity and specificity of UT for acute pancreatitis were, respectively, 100% (95% confidence interval [CI] = 77% to 100%) and 96% (95% CI = 92% to 98%). Seven of the 17 patients with pancreatitis (41%) had diagnostic findings on CT and positive UT tests but had nondiagnostic plasma lipase and amylase levels.. A POC UT screening test for pancreatitis in the ED compared favorably with plasma lipase and amylase levels. Future studies should be performed to explore whether this test in the ED setting has better clinical utility than plasma lipase or amylase.

Topics: Abdominal Pain; Acute Disease; Amylases; Humans; Lipase; Pancreatitis; Pancreatitis, Chronic; Point-of-Care Systems; Prospective Studies; Sensitivity and Specificity; Trypsinogen

Acute recurrent/chronic pancreatitis (CP) is a complex multigenic disease. This is a case-control study consisting of 25 Greek patients with CP and a control population of 236 healthy Greek subjects. The whole coding area and neighboring intronic regions of the three genes were screened. Seventeen of 25 patients (68%) had mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene: nine compound heterozygotes with either mild or severe mutations and eight heterozygotes. Four patients (16%) carried CFTR-modulating haplotypes V470-TG11-T5 and V470-TG12-T7. All were negative for PRSS1 gene mutations, while variants c.486C/T and c.738C/T were found in nine patients each, three homozygotes for the minor alleles. Two carried SPINK1 gene mutation p.N34S, one being transheterozygote with CFTR mutation p.F1052V. The promoter variant -253T>C was found in four individuals (one homozygous for the minor allele), all four being transheterozygotes with mutations in the CFTR gene as well. Finally two carried c.272C/T in the 3' untranslated region, one being a p.N34S carrier as well. In total, 80% (20/25) of patients had a molecular defect in one or both of the CFTR and SPINK1 genes, suggesting that mutations/variants in the CFTR plus or minus mutations in the SPINK1, but not the PRSS1 gene, may confer a high risk for recurrent pancreatitis.

Topics: Adolescent; Adult; Carrier Proteins; Case-Control Studies; Child; Child, Preschool; Cystic Fibrosis Transmembrane Conductance Regulator; DNA Mutational Analysis; Female; Genetic Predisposition to Disease; Humans; Male; Middle Aged; Mutation; Pancreatitis, Chronic; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Hereditary pancreatitis is a rare, autosomal dominant, inherited disease characterized by recurrent attacks of acute pancreatitis with the development of chronic pancreatitis and an increased risk of pancreatic cancer. R122H or N29I mutation in cationic trypsinogen (protease serine 1, PRSS1) gene causes hereditary pancreatitis. R122H mutation is the most common mutation that causes pancreatitis by preventing deactivation of trypsin within the pancreas and prolonging its action. Three members of the family, the patient, her elder son, and her niece experienced recurrent attacks of pancreatitis. We analyzed five exons of the PRSS1 gene in DNA samples of five family members including her husband and younger son who were asymptomatic. We found out that four members of the family, the patient, her two sons, and her niece, had R122H mutation in the exon 3 of PRSS1 gene. Finally, we diagnosed hereditary pancreatitis in two households in the same family.

Topics: Adolescent; Adult; Amino Acid Substitution; Cholangiopancreatography, Endoscopic Retrograde; Female; Humans; Mutation; Pancreatitis, Chronic; Pedigree; Sequence Analysis, DNA; Tomography, X-Ray Computed; Trypsin; Trypsinogen

Missense mutations in human cationic trypsinogen PRSS1 are frequently detected in patients with hereditary pancreatitis, a rare genetic disease of the pancreas characterized by autodigestive necrosis, chronic inflammation, and fibrosis. To examine the link between PRSS1 mutations and the initiation and progression of hereditary pancreatitis, we have sought to generate a transgenic mouse that carries a missense mutation in the PRSS1 that is most frequently observed in patients.. A transgenic mouse was generated in which the expression of the mouse PRSS1 mutant R122H (R122H_mPRSS1) is targeted to pancreatic acinar cells by fusion to the elastase promoter. The expression of the mutant trypsinogen was assessed by immunohistochemical staining and real-time reverse transcription polymerase chain reaction analysis. The relationship between transgene expression and inflammation was analyzed by morphologic assessment of H&E-stained tissue sections, responsiveness to cerulein-induced pancreatitis, and immunohistochemical identification of cellular and biochemical components of the inflammatory response.. Pancreata from transgenic mice display early-onset acinar cell injury and inflammatory cell infiltration. With progressing age, the transgenic mice develop pancreatic fibrosis and display acinar cell dedifferentiation. Moreover, the expression of R122H_mPRSS1 transgene is associated with enhanced response to cerulein-induced pancreatitis. Finally, cell-specific activation of the inflammation-associated signaling pathways, c-jun-N-terminal kinase and extracellular signal-regulated kinase, was observed in response to expression of R122H_mPRSS1.. These results underscore the importance of PRSS1 mutations as pathogenic mediators of hereditary pancreatitis and indicate that persistent pancreatic injury might be causally linked to chronic pancreatitis.

Topics: Animals; Ceruletide; Disease Models, Animal; Disease Progression; DNA; Gene Expression Regulation; Inflammation; Mice; Mice, Inbred C57BL; Mice, Transgenic; Mutation, Missense; Pancreas; Pancreatitis, Chronic; Phenotype; Trypsinogen

Hereditary pancreatitis should be assumed if other risk factors for the disease can not been identified and if the patient has a family history for recurrent pancreatitis, chronic pancreatitis or pancreatic cancer. Since patients with chronic pancreatitis due to mutations in the cationic trypsinogen-gene have a much higher lifetime risk of developing pancreatic cancer, specifically if they are smokers, an adequate long-term follow up in specialized centers is recommended. The most frequent genetic changes in patients with hereditary pancreatitis are mutations in the cationic trypsinogen gene. Mutations in the CFTR-gene or SPINK1-gene have been reported in patients with idiopathic pancreatitis. The clinical relevance and the therapeutic consequences of these mutations is still controversial. Genetic testing is recommended when a patient with idiopathic pancreatitis is under 25 years at diagnosis or when one or more family members have either pancreatitis or pancreatic cancer. Genetic analysis of asymptomatic family members should only be offered after adequate genetic counselling. Prenatal diagnostic is not recommended.

Topics: Adult; Carrier Proteins; Chromosome Aberrations; Cystic Fibrosis Transmembrane Conductance Regulator; DNA Mutational Analysis; Genes, Dominant; Genetic Counseling; Humans; Pancreatic Neoplasms; Pancreatitis, Chronic; Prognosis; Trypsin; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen

Topics: Animals; Cystic Fibrosis Transmembrane Conductance Regulator; Disease Models, Animal; DNA; Gene Expression Regulation; Mice; Mice, Transgenic; Mutation, Missense; Pancreas; Pancreatitis, Chronic; Trypsin Inhibitor, Kazal Pancreatic; Trypsinogen