Dysfunction of the pancreas in healthy smoking persons and patients with chronic pancreatitis

Importance of Genetic Polymorphisms in MT1 and MT2 Genes in Metals Homeostasis and Their Relationship with the Risk of Acute Pancreatitis Occurrence in Smokers-Preliminary Findings

This study was aimed at evaluating the changes in metallothionein (MT) concentration in the blood of patients with acute pancreatitis (AP) and healthy subjects, taking into account the extracellular (plasma) and intracellular (erythrocyte lysate) compartments. The impact of single-nucleotide polymorphisms (SNPs) in the MT1A (rs11640851), MT1B (rs964372) and MT2A (rs10636) genes on MT concentration and their association with the concentration of metals (Cu, Zn, Cd) and ceruloplasmin as Cu-related proteins were analyzed. The concentration of a high-sensitivity C-reactive protein (hs-CRP) and IL-6 as markers of inflammation, and malonyldialdehyde (MDA), superoxide dismutase (SODs) activity and the value of total antioxidant capacity (TAC) as parameters describing the pro/antioxidative balance were also assessed. In the AP patient groups, an increased MT concentration in erythrocyte lysate compared to healthy subjects was shown, especially in individuals with the GG genotype for rs964372 in the MT1B gene. A Zn concentration was especially decreased in the blood of smoking AP patients with the AA genotype for SNP rs11640851 in the MT1A gene and the GC genotype for SNP rs10636 in MT2A, compared to non-smokers with AP, which was accompanied by an increase in the value of the Cu/Zn ratio. The exposure to tobacco smoke xenobiotics increased the risk of AP occurrence in subjects with the CC genotype for SNP rs11640851 in the MT1A gene by more than fourfold. The investigated polymorphisms, rs11640851 in the MT1A gene, rs964372 in the MT1B gene and rs10636 in the MT2A gene, seem to be an important factor in maintaining homeostasis in an organism under oxidative stress conditions.

Risk Factors Associated With Progression Toward Endocrine Insufficiency in Chronic Pancreatitis

OBJECTIVE

Little data exist describing the change over time in islet function and glycemic control in patients with chronic pancreatitis (CP).

METHODS

In 325 CP patients who underwent 2 mixed meal tolerance tests and/or glycated hemoglobin (HbA1c) levels, we estimated the rate of change in metabolic measures per 6 months and assessed the association between potential risk factors for diabetes and rate of change using multivariate regression models.

RESULTS

Per 6-month time, HbA1c increased by 0.062% with a standard error of 0.029% (P = 0.037) and the ratio (area under the curve (AUC) C-peptide to AUC glucose from mixed meal tolerance testing) decreased by 0.0028 with a standard error of 0.0011 (P = 0.014). We observed more rapid decline in smokers (AUC C-peptide, P = 0.043) and patients with surgical drainage (AUC glucose, P = 0.001; ratio, P = 0.03) or with calcific pancreatitis (HbA1c, P = 0.003). In multivariate models, AUC C-peptide and ratio declined at a greater rate in smokers and HbA1c in those with pancreatic calcifications (both P < 0.05).

CONCLUSIONS

We observed a measurable decline in β-cell function and glycemic control in patients with CP. Patients with a history of tobacco smoking, surgical drainage, or pancreatic calcification may be at highest risk.

Diabetes mellitus secondary to pancreatic diseases (type 3c): The effect of smoking on the exocrine-endocrine interactions of the pancreas

The present study was conducted to ascertain how cigarette smoke affects the exocrine-endocrine interactions of the human pancreas with diabetes mellitus secondary to pancreatic diseases (type 3c). Blood has been collected from smoking and non-smoking healthy individuals as well as from patients with diagnosed chronic pancreatitis and diabetes type 3c. The concentrations of interleukin-6, endothelin-1 and insulin in the plasma were determined by enzyme-linked immunosorbent assay (ELISA) tests. The activities of amylase and lipase in the serum, as well as the lipid profile, creatinine, uric acid and urea concentrations, were measured using colorimetric methods. Samples of normal pancreatic tissue and chronic pancreatitis were verified histopathologically and then interleukin-6, endothelin-1, insulin and glucagon were localized by immunohistochemical staining using a monoclonal anti-human antibody. The highest levels of interleukin-6 and endothelin-1 and the lowest levels of insulin and glucagon intensity from the immunostaining were observed in smoking patients with diabetes. In all smoking patients with pancreatitis and diabetes, there was a significant elevation in interleukin-6 and endothelin-1 concentration and amylase and lipase activities, hyperlipidaemia and a lower value of estimated glomerular filtration rate and blood urea nitrogen when compared to non-smokers. Our study confirmed that smoking exerts a pro-inflammatory effect and disturbs the exocrine-endocrine interactions of the pancreas.

The impact of smoking on the development of diabetes and its complications

Diabetes is one of the most common metabolic disorders and emerges secondary to an interaction between genetic, environmental and lifestyle factors. This work provides an overview of the impact of smoking on the development of vascular complications in this condition and also provides an overview of the potential role of smoking in predisposition to diabetes. There are many studies documenting the impact of smoking on health (not focused on patients with diabetes), suggesting that the health exposure in these individuals is at least comparable to that observed in the general population. Distinct studies of smoking in patients with diabetes have unambiguously confirmed an increased prevalence and a higher risk of early death associated with the development of macrovascular complications. Smoking is also associated with premature development of microvascular complications and may contribute to the pathogenesis of type 2 diabetes. It has been shown that smoking is a predictor of the progression of glucose intolerance at both the transition from normoglycaemia to impaired glucose tolerance status and the increased risk of developing diabetes. The mechanisms explaining the relationship between smoking and the development of diabetes are not fully understood, although a number of hypotheses have been put forward. Current evidence indicates that smoking cessation is not only important to prevent macrovascular complications in diabetes, but also has a role in limiting microvascular disease and may also facilitate glycaemic management in this condition.

The effect of ozone on the expression of metallothionein in tissues of rats chronically exposed to cadmium

Our aims were to evaluate the expression of metallothionein (MT) in an experimental rat model which experienced chronic exposure to cadmium (Cd) and to measure its expression after ozone therapy (OT) or oxygen (Ox) in the same model, as compared to the control group, which was exposed to neither cadmium nor ozone. Forty male Wistar rats were divided into 5 groups: control, Cd, Cd and Ox, Cd and Oz, and Oz. During our research, Cd concentration (ASA) and MT concentration (ELISA) were determined in supernatants of the kidneys, liver and pancreas. SDS-PAGE analyses and immunohistochemical localization were used to evaluate the level of MT expression in the tissue. In rats intoxicated with Cd, the highest concentration of both Cd and MT was observed in the kidneys and liver, with a significantly lower concentration measured in the pancreas. Ozone therapy reduces the accumulation of cadmium in the liver and kidneys, resulting in a reduced expression of metallothionein in those tissues.

Somatostatin expression in the pancreatic cells of smoking and non-smoking chronic pancreatitis patients with or without diabetes

OBJECTIVES

The aim of the analysis is to determine the location and degree of the hormone immunoreactivity in tissues of patients with chronic pancreatitis and diabetes.

METHODS

The study was performed on 11 non-smoking and 12 smoking patients with chronic pancreatitis (CP) with/without diabetes. The hormone was located in the pancreatic tissues by means of the immunohistochemical method using somatostatin antibodies. The histopathological evaluation of the hormone expression intensity in tissue sections was carried out using the semi-quantitative method and was calculated by means of a digital image analysis.

RESULTS

The hormone's strong immunohistochemical reaction and the modified D-cell location may be a result of the pancreatic tissue fibrosis process prevention in patients with CP. Changes in the intensity of SS immunoreactivity and the D-cell distribution in the pancreas of patients with CP and diabetes may possibly result from the additional hormone compensatory effect in the excessive glucagon secretion inhibition. Smoking patients with diabetes showed significantly higher hormone immunostaining in the pancreas compared to non-smoking patients without diabetes and healthy persons.

CONCLUSIONS

The severity of histopathological changes in smoking CP patients indicates that the cigarette smoke components may further exacerbate the inflammatory reactions. Patients with CP were found to have a strong immunohistochemical reaction to SS and changes in the distribution of D cells when compared to healthy patients. The strongest immunohistochemical SS reaction has been identified in the pancreatic tissue from smoking patients with diabetes.

Axonal guidance signaling pathway interacting with smoking in modifying the risk of pancreatic cancer: a gene- and pathway-based interaction analysis of GWAS data

Cigarette smoking is the best established modifiable risk factor for pancreatic cancer. Genetic factors that underlie smoking-related pancreatic cancer have previously not been examined at the genome-wide level. Taking advantage of the existing Genome-wide association study (GWAS) genotype and risk factor data from the Pancreatic Cancer Case Control Consortium, we conducted a discovery study in 2028 cases and 2109 controls to examine gene-smoking interactions at pathway/gene/single nucleotide polymorphism (SNP) level. Using the likelihood ratio test nested in logistic regression models and ingenuity pathway analysis (IPA), we examined 172 KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, 3 manually curated gene sets, 3 nicotine dependency gene ontology pathways, 17 912 genes and 468 114 SNPs. None of the individual pathway/gene/SNP showed significant interaction with smoking after adjusting for multiple comparisons. Six KEGG pathways showed nominal interactions (P < 0.05) with smoking, and the top two are the pancreatic secretion and salivary secretion pathways (major contributing genes: RAB8A, PLCB and CTRB1). Nine genes, i.e. ZBED2, EXO1, PSG2, SLC36A1, CLSTN1, MTHFSD, FAT2, IL10RB and ATXN2 had P interaction < 0.0005. Five intergenic region SNPs and two SNPs of the EVC and KCNIP4 genes had P interaction < 0.00003. In IPA analysis of genes with nominal interactions with smoking, axonal guidance signaling $$\left(P=2.12\times 1{0}^{-7}\right)$$ and α-adrenergic signaling $$\left(P=2.52\times 1{0}^{-5}\right)$$ genes were significantly overrepresented canonical pathways. Genes contributing to the axon guidance signaling pathway included the SLIT/ROBO signaling genes that were frequently altered in pancreatic cancer. These observations need to be confirmed in additional data set. Once confirmed, it will open a new avenue to unveiling the etiology of smoking-associated pancreatic cancer.

Immunohistochemical localization of somatostatin and pancreatic polypeptide in smokers with chronic pancreatitis

Recent studies have demonstrated a significant role of tobacco smoking in the development of chronic pancreatitis. Although there are published papers on the effects of cigarette smoking on insulin secretion in patients, no data are available on the effects of smoking on pancreatic endocrine cells secreting somatostatin and pancreatic polypeptide. The aim of the study was to evaluate the effects of cigarette smoking on endocrine pancreatic function by immunolocalization of somatostatin and pancreatic polypeptide in the pancreas from smokers and non-smoking patients with chronic pancreatitis in comparison with healthy controls. The LSAB2-HRP technique with polyclonal antibodies was used for the immunolocalization of somatostatin and pancreatic polypeptide in histological preparations of the pancreas. The intensity of immunohistochemical reaction was calculated with digital image analysis. The study demonstrated increased numbers of somatostatin (D) secreting cells and pancreatic polypeptide (PP) cells and their altered location in pancreatic islets and parenchyma of smoking patients with chronic pancreatitis, as compared to non-smoking patients and healthy controls. Smoking patients showed significantly higher immunostaining of the hormones in the pancreas compared to non-smoking patients and healthy persons. This study indicates that smoking may play a significant role in the development of endocrine disturbances in the development of chronic pancreatitis.

Selective expression of CYP2A13 in human pancreatic α-islet cells

Exposure to cigarette smoke is an etiological factor of human pancreatic cancer and has been associated with an increased risk of pancreatic diseases, including pancreatitis and diabetes. The toxicants in cigarette smoke can reach pancreatic tissue, and most of the toxicants require cytochrome P450 (P450)-mediated metabolic activation to exert their toxicity. Among all the human P450 enzymes, CYP2A13 is the most efficient enzyme in the metabolic activation of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a major tobacco-specific toxicant and a suspected human carcinogen. It also metabolically activates 4-aminobiphenyl, another toxicant in cigarette smoke. Immunohistochemical analysis in this study demonstrated that CYP2A13 was selectively expressed in the islets but not in the exocrine portion of adult human pancreas. Further study using dual immunofluorescence labeling technique showed that CYP2A13 protein was mainly expressed in the α-islet but not in β-islet cells. The selective expression of CYP2A13 in human pancreatic α-islet cells suggests that these islet cells could be damaged by the toxicants existing in cigarette smoke through CYP2A13-mediated in situ metabolic activation. Our result provides a mechanistic insight for human pancreatic diseases that have been associated with cigarette smoke exposure.

The pathobiological impact of cigarette smoke on pancreatic cancer development (review)

Despite extensive efforts, pancreatic cancer remains incurable. Most risk factors, such as genetic disposition, metabolic diseases or chronic pancreatitis cannot be influenced. By contrast, cigarette smoking, an important risk factor for pancreatic cancer, can be controlled. Despite the epidemiological evidence of the detrimental effects of cigarette smoking with regard to pancreatic cancer development and its unique property of being influenceable, our understanding of cigarette smoke-induced pancreatic carcinogenesis is limited. Current data on cigarette smoke-induced pancreatic carcinogenesis indicate multifactorial events that are triggered by nicotine, which is the major pharmacologically active constituent of tobacco smoke. In addition to nicotine, a vast number of carcinogens have the potential to reach the pancreatic gland, where they are metabolized, in some instances to even more toxic compounds. These metabolic events are not restricted to pancreatic ductal cells. Several studies show that acinar cells are also greatly affected. Furthermore, pancreatic cancer progenitor cells do not only derive from the ductal epithelial lineage, but also from acinar cells. This sheds new light on cigarette smoke-induced acinar cell damage. On this background, our objective is to outline a multifactorial model of tobacco smoke-induced pancreatic carcinogenesis.

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Smoking is related to pancreatic fibrosis in humans

OBJECTIVES

Smokers are at risk for pancreatic cancer (PC) and other pancreatic diseases. Cigarette smoking also aggravates the risk of PC in patients with hereditary and chronic pancreatitis (CP) and results in a higher incidence of acute pancreatitis and relapses in CP. Both PC and CP are characterized by a progressive fibrosis. Recently, two studies on rats reported that tobacco smoking is associated with chronic pancreatic inflammation with fibrosis and scarring of pancreatic acinar structures. In this study, we aimed to confirm a relationship between cigarette smoking and pancreatic fibrosis (PF) in humans.

METHODS

In this retrospective study, pancreatic and liver tissue acquired during autopsy was collected and analyzed. PF was scored by assessing severity of intralobular, extralobular, and total PF: grade 0 (normal or mild; 0-25% PF), grade 1 (moderate; 25-50% PF), and grade 2 (severe; >50%). Information on smoking habits was extracted from (electronic) medical records.

RESULTS

Of 900 autopsies performed from January 2005 to December 2007, a minority of patients (n=111) met all inclusion criteria for analysis. Grade 2-3 total PF and intralobular PF was significantly more present in smokers vs. "never-smokers" (total: 42.9 vs. 26.5%, P=0.027 and intralobular: 39.3 vs. 15.6%, P=0.013), whereas no differences could be found between never-smokers and ex-smokers and between ex-smokers and smokers. When we took into account interlobular PF, no differences between all groups were observed. No relationship between PF and age (P=0.893), body mass index (P=0.707), and pancreatic lipomatosis (P=0.916) was observed.

CONCLUSIONS

To our knowledge, no study in humans had studied the effect of tobacco smoking on pancreatic tissue. We have demonstrated for the first time that current cigarette smoking is associated with total PF-specifically, intralobular PF-as compared with nonsmokers.

Change of zinc, copper, and metallothionein concentrations and the copper-zinc superoxide dismutase activity in patients with pancreatitis

OBJECTIVES

The aims of the present studies were to measure the concentrations of zinc (Zn), copper (Cu), and metallothionein and the Cu/Zn superoxide dismutase activity as elements engaged in an essential manner in the prooxidative and antioxidative balance of organism and to demonstrate the degree to which metallothionein and Cu/Zn superoxide dismutase are involved in the inflammatory processes occurring in the pancreas.

METHODS

The concentration of metallothionein was measured by immunoenzymatic method. Serum Cu/Zn superoxide dismutase activity was determined using a commercial test. The measurements of Zn and Cu concentrations in serum were assessed with the use of flame atomic absorption spectrometry.

RESULTS

Lowered serum Zn concentration and higher Cu level were observed in the serum of patients with chronic exacerbated pancreatitis and chronic pancreatitis. The significant increase of metallothionein concentration and Cu/Zn superoxide dismutase activity was observed in the blood of patients with chronic exacerbated pancreatitis and chronic pancreatitis. In slices of the pancreas during pancreatitis, we observed in immunohistochemical reaction the variable involvement of Cu/Zn superoxide dismutase and metallothionein.

CONCLUSIONS

The results presented in these studies indicate an essential and variable involvement of antioxidants such Cu/Zn superoxide dismutase and metallothionein and disordered Cu and Zn homeostasis depending on the progression of inflammatory processes in patients with pancreatitis.

Chronic pancreatitis

PURPOSE OF REVIEW

As in previous reviews in this journal, this review is focused on the most important new observations in chronic pancreatitis made in the last year.

RECENT FINDINGS

Important observations included the search for biomarkers and alternative methods for the detection of early chronic pancreatitis; stellate cell activation and their role in fibrogenesis; the natural history of chronic pancreatitis; reports outlining the complexity in diagnosis of autoimmune pancreatitis; emerging roles of endoscopic ultrasound and magnetic resonance cholangiopancreatography in chronic pancreatitis diagnosis; a better understanding of neurobiology of chronic pancreatitis pain; and the potential role of surgery as first-line therapy in advanced chronic pancreatitis.

SUMMARY

In 2007, major advances were made in our understanding of central processing in chronic pancreatitis pain. New techniques are being utilized in search of a better means to diagnose early chronic pancreatitis. Important prospective studies are emerging, which compare endoscopic and surgical interventions. Furthermore, the complexities of diagnosing autoimmune pancreatitis are being recognized. Overall, the future is promising as advances in genomic and proteomic techniques are applied to improve our understanding of chronic pancreatitis.