Age-dependent difference in factors affecting choice of system for self-monitoring of blood glucose

To clarify factors determining the preference for a self-monitoring blood glucose (SMBG) system in patients with diabetes mellitus. A total of 52 Japanese inpatients with diabetes mellitus were recruited into a single-center trial. After the patients got used to one SMBG system, the SMBG system was substituted with another one of the three, and the subjects were given questionnaires. The following parameters were identified as independent factors associated with the preference of SMBG: display (P<0.0001), operation for inserting strips (P=0.0004), and lancing-device operation (P<0.05). When the subjects were divided according to age, the independent variables associated with overall preference in the older group (>or=60 years) were display (P=0.001) and procedure for detaching a used needle (P=0.01), whereas those in the younger group (age<60 years) were operation of the lancing device (P<0.0001), operation to apply blood to strip (P=0.001), and amount of blood (P=0.04). These data suggest that in elderly patients with diabetes, display and detachment of the needle are important factors affecting the choice of SMBG system, whereas younger subjects give weight to skin puncture-related issues in choosing an SMBG system.

Is central obesity a good predictor of carotid atherosclerosis in Japanese type 2 diabetes with metabolic syndrome?

Metabolic syndrome has been revealed to be a major risk factor for cardiovascular disease (CVD) and early mortality in non-diabetic and diabetic patients. In 2005, the International Diabetes Federation (IDF) and the Examination Committee of Criteria for Diagnosis of Metabolic Syndrome in Japan published new definitions of metabolic syndrome in which central obesity was an indispensable factor. However, the significance of this new definition to CVD in type 2 diabetes has not yet been clarified. A cross-sectional study was conducted with 294 Japanese type 2 diabetic patients without known cardiovascular disease to evaluate the association between metabolic syndrome defined by this new definition and carotid atherosclerosis, and the significance of central obesity for the prediction of the development of carotid atherosclerosis. In a multivariate regression analysis, metabolic syndrome but not central obesity was significantly associated with carotid intima-media thickness (IMT) independent of known cardiovascular risk factors (p<0.05). In addition, whereas carotid IMT was significantly increased according to the increase in the number of components of metabolic syndrome, it was not significantly different between the groups with the same number of components of metabolic syndrome with or without central obesity. These findings suggest that the prediction of the development of carotid atherosclerosis in Japanese type 2 diabetic patients could be improved by the assessment of aggregation of components of metabolic syndrome rather than with or without metabolic syndrome by this new definition.

Magnetic field switching between the two orbital-ordered states in DyVO3

The critical phase competition between different spin-orbital-ordered states has been investigated for the DyVO3 single crystal. As temperature is lowered, the compound exhibits a reentrant spin and orbital ordering (SO and OO) transition: C-->G-->C type for SO and G-->C-->G type for OO. It was found that a magnetic field also drives the phase transition from C to G for OO and concomitantly from G to C for SO, the latter of which is coupled with the metamagnetic transition of the Dy 4f moments. The mechanism of this novel magnetic-field-induced orbital switching is discussed.

Clustering of several cardiovascular risk factors affects tissue characteristics of the carotid artery

Integrated backscatter (IBS) signal obtained by extracranial ultrasound examination of the carotid artery can be used to evaluate the tissue characteristics of arterial plaque. To examine whether clustering of several cardiovascular risk factors, metabolic syndrome (MetS), affects the tissue characteristics of the carotid artery, we measured Calibrated-IBS values of the intima-media complex in the carotid artery for 142 patients (61.6+/-9.5 years old) with at least one component of MetS. Calibrated-IBS values were inversely correlated with the number of MetS components (r=-0.224, p=0.0073). Furthermore, the number of MetS components was an independent risk factor for a low Calibrated-IBS. The subjects with coronary heart disease (CHD) (n=20) showed significantly lower Calibrated-IBS than those without it (n=122) (-17.8+/-5.1 vs. -21.7+/-5.5 dB, p=0.0020), and the logistic regression analysis showed that the presence of CHD was associated with Calibrated-IBS (RR=0.898, 95%CI: 0.811-0.994, p=0.0374). These results suggest that clustering of the cardiovascular risk factors affects the Calibrated-IBS, an acoustic parameter of tissue characteristics of the intima-media complex in the carotid artery.

Tissue-specific deletion of c-Jun in the pancreas has limited effects on pancreas formation

It is well known that activating protein-1 (AP-1) is involved in a variety of cellular functions such as proliferation, differentiation, apoptosis, and oncogenesis. AP-1 is a dimer complex consisting of different subunits, and c-Jun is known to be one of its major components. In addition, it has been shown that mice lacking c-Jun are embryonic lethal and that c-Jun is essential for liver and heart development. However, the role of c-Jun in the pancreas is not well known. The aim of this study was to examine the possible role of c-Jun in the pancreas. First, c-Jun was strongly expressed in pancreatic duct-like structures at an embryonic stage, while a lower level of expression was observed in some part of the adult pancreas, implying that c-Jun might play a role during pancreas development. Second, to address this point, we generated pancreas-specific c-Jun knock-out mice (Ptf1a-Cre; c-Jun(flox/flox) mice) by crossing Ptf1a-Cre knock-in mice with c-Jun floxed mice. Ptf1a is a pancreatic transcription factor and its expression is confined to pancreatic stem/progenitor cells, which give rise to all three types of pancreatic tissue: endocrine, exocrine, and duct. Contrary to our expectation, however, there was no morphological difference in the pancreas between Ptf1a-Cre; c-Jun(flox/flox) and control mice. In addition, there was no difference in body weight, pancreas weight, and the expression of various pancreas-related factors (insulin, glucagon, cytokeratin, and amylase) between the two groups. Furthermore, there was no difference in glucose tolerance between Ptf1a-Cre; c-Jun(flox/flox) and control mice. Taken together, although we cannot exclude the possibility that c-Jun ablation is compensated by some unknown factors, c-Jun appears to be dispensable for pancreas development at least after ptf1a gene promoter is activated.

Establishment of a non-invasive mouse reporter model for monitoring in vivo pdx-1 promoter activity

It is well known that pancreatic and duodenal homeobox gene-1 (PDX-1) plays a crucial role in beta-cell differentiation, and maintaining mature beta-cell function. Thus, it is important to understand how pdx-1 gene is regulated under various pathophysiological conditions in vivo. In this study, to non-invasively and quantitatively monitor pdx-1 promoter activity in vivo, we constructed a pdx-1 promoter-SEAP-IRES-GFP reporter plasmid. In this construct, the -4.6kb pdx-1 promoter region sufficient for driving beta-cell-selective PDX-1 expression was inserted to the upstream of the secreted alkaline phosphatase (SEAP) reporter gene. It is noted here that the pdx-1 promoter-mediated SEAP activity can be distinguished from endogenous alkaline phosphatase activity. First, we transfected the construct in mouse beta-cell line MIN6 and human hepatocellular carcinoma cell line HepG2. SEAP activity was readily detected in the media of MIN6 cells, but not in HepG2 cells. These results indicate that this construct specifically reports beta-cell-specific pdx-1 promoter activity in a cell culture system. Based on these in vitro findings, we next generated transgenic mice using the same construct. SEAP activity was readily detected in serum of the transgenic mice, but not in their littermate mice. Furthermore, SEAP activity was detected in protein extract from the transgenic pancreas and slightly from the transgenic duodenum, but not from the liver, and brain. These results indicate that serum SEAP activity likely represents in vivo pdx-1 promoter activity. This transgenic mouse model would be useful to non-invasively monitor in vivo pdx-1 promoter activity and to screen new molecules which regulate PDX-1 expression.

Desmin as a marker of proteinuria in early stages of membranous nephropathy in elderly patients

AIMS AND METHOD

Idiopathic membranous nephropathy (IMN) is the most common cause of nephrotic syndrome in adults worldwide. Many patients with IMN are elderly, but little is known about the relationship regarding the morphological stage determined by electron microscopy (EM), the amount of proteinuria, and the expression of glomerular podocyte markers such as desmin and nephrin in nephrotic glomeruli in IMN. We studied 59 patients with histopathologically proven IMN. We compared the clinical features, EM stage classification, and the immunohistochemical features of glomerular expression of podocyte markers, including desmin and nephrin, between older (age > or = 60 years) and younger (age < 60 years) patients. We also investigated these parameters in patients with minimal-change nephrotic syndrome (MCNS), minor glomerular abnormalities (MGA), and normal kidneys as age-matched controls.

RESULTS

Prevalence of nephrotic syndrome was significantly higher in the older (52.9%) than the younger group (20.0%) of IMN. The level of proteinuria was higher in early stages (Stages I + II) than in late stages (Stages III + IV) in IMN. The glomerular expression of desmin in podocytes was significantly higher in IMN as compared to MCNS, MGA, or age-matched controls. Desmin expression was significantly increased in earlier EM stages (Stages I + II) and in higher proteinuric group (daily proteinuria > or = 1 g) of older patients with IMN. Reciprocally, the reduced expression of nephrin was associated with the early EM stages (Stages I + II) of patients with IMN.

CONCLUSIONS

We conclude that the expression of desmin in podocytes is upregulated in patients with IMN as compared to other glomerular diseases including MCNS or MGA, or to controls. In elderly patients with IMN, desmin expression was associated with early EM stages and heavy proteinuria, which may reflect phenotypic alteration of the podocyte.

MafA regulates expression of genes important to islet beta-cell function

Insulin transcription factor MafA is unique in being exclusively expressed at the secondary and principal phase of insulin-expressing cell production during pancreas organogenesis and is the only transcriptional activator present exclusively in islet beta-cells. Here we show that ectopic expression of MafA is sufficient to induce a small amount of endogenous insulin expression in a variety of non-beta-cell lines. Insulin mRNA and protein expression was induced to a much higher level when MafA was provided with two other key insulin activators, pancreatic and duodenal homeobox (PDX-1) and BETA2. Potentiation by PDX-1 and BETA2 was entirely dependent upon MafA, and MafA binding to the insulin enhancer region was increased by PDX-1 and BETA2. Treatment with activin A and hepatocyte growth factor induced even larger amounts of insulin in AR42J pancreatic acinar cells, compared with other non-beta endodermal cells. The combination of PDX-1, BETA2, and MafA also induced the expression of other important regulators of islet beta-cell activity. These results support a critical role of MafA in islet beta-cell function.

A novel index of insulin resistance determined from the homeostasis model assessment index and adiponectin levels in Japanese subjects

Insulin resistance is the principal cause of glucose intolerance and type 2 diabetes and induces progression of severe atherosclerosis in these patients. Adiponectin, the adipose-specific proteins, is known to correlate negatively with insulin resistance in patients with obesity and type 2 diabetes. The purpose of this study was to evaluate the potential of using serum adiponectin levels as a marker of insulin resistance in various states of insulin resistance. Furthermore, we attempted to establish a modified index of the homeostasis model assessment index (HOMA-IR), calculated from the product of serum insulin and plasma glucose levels divided by serum adiponectin levels (HOMA-AD). We recruited 117 Japanese subjects with various degrees of glucose tolerance and determined serum adiponectin levels and insulin sensitivity (M-value) by using the euglycemic hyperinsulinemic clamp technique. M-value, the gold standard index of insulin resistance, correlates significantly and independently with fasting insulin (r=-0.313, P<0.001), glucose (r=-0.319, P<0.001), and adiponectin (r=0.241, P<0.002) levels. M-values were more significantly correlated with HOMA-AD (r=-0.643, P<0.001) than HOMA-IR values (r=-0.591, P<0.001). In subjects with moderate hyperglycemia (fasting glucose levels>8.0mmol/L, n=30), HOMA-AD showed a more significant correlation with the M-value than HOMA-IR (r=-0.535, P=0.005 versus r=-0.461, P=0.010). We would therefore like to propose a novel index, HOMA-AD, as a simple and adequate index for determining insulin resistance even in diabetic patients with overt hyperglycemia.

Electric control of spin helicity in a magnetic ferroelectric

Magnetic ferroelectrics or multiferroics, which are currently extensively explored, may provide a good arena to realize a novel magnetoelectric function. Here we demonstrate the genuine electric control of the spiral magnetic structure in one such magnetic ferroelectric, TbMnO3. A spin-polarized neutron scattering experiment clearly shows that the spin helicity, clockwise or counterclockwise, is controlled by the direction of spontaneous polarization and hence by the polarity of the small electric field applied on cooling.

Involvement of oxidative stress in the pathogenesis of diabetes

Pancreatic beta-cell failure is the common characteristic of type 1 and type 2 diabetes. Type 1 diabetes is induced by pancreatic beta-cell destruction, which is mediated by an autoimmune mechanism and consequent inflammatory process. Various inflammatory cytokines and oxidative stress produced by islet-infiltrating immune cells have been proposed to play an important role in mediating the destruction of beta cells. The JNK pathway is also activated by such cytokines and oxidative stress and is involved in beta-cell destruction. Type 2 diabetes is the most prevalent and serious metabolic disease affecting people all over the world. Pancreatic beta-cell dysfunction and insulin resistance are the hallmark of type 2 diabetes. Once hyperglycemia becomes apparent, beta-cell function gradually deteriorates, and insulin resistance is aggravated. This process is called "glucose toxicity." Under such conditions, oxidative stress is provoked, and the JNK pathway is activated, which is likely involved in pancreatic beta-cell dysfunction and insulin resistance. In addition, oxidative stress and activation of the JNK pathway are involved in the progression of atherosclerosis, which is often observed under diabetic conditions. Taken together, it is likely that oxidative stress and subsequent activation of the JNK pathway are involved in the pathogenesis of type 1 and type 2 diabetes.

Focal cerebral ischemia/reperfusion injury in mice induces hematopoietic prostaglandin D synthase in microglia and macrophages

Hematopoietic prostaglandin D synthase is a key enzyme in synthesis of prostaglandin D. Hematopoietic prostaglandin D synthase is expressed in microglia of the developing mouse brain. This study determined the serial changes and cellular localization of hematopoietic prostaglandin D synthase, and its role in cerebral ischemia/reperfusion injury using C57BL/6 mice (n=84) and bone marrow chimera mice (n=16). The latter mice were selected based on their expression of enhanced green fluorescent protein in bone marrow/blood-derived monocytes/macrophages. The middle cerebral artery was occluded for 60 min, followed by reperfusion. Hematopoietic prostaglandin D synthase expression was examined by immunohistochemistry and Western blotting. Hematopoietic prostaglandin D synthase-positive cells were mainly expressed in the peri-ischemic area at 12 h (P<0.05) and 24 h (P<0.001) after reperfusion, while they were mostly found in the transition area at 48-72 h postreperfusion (P<0.001). There was a significant increase in staining intensity as well as number of hematopoietic prostaglandin D synthase-positive cells in the ischemic core at 5-7 (P<0.001) days postreperfusion. Hematopoietic prostaglandin D synthase-positive cells also co-expressed ionized calcium-binding adapter molecule 1, a marker of microglia/macrophages, and cyclooxygenase-2, but not markers of neurons, oligodendrocytes and astrocytes. Until 72 h postreperfusion, many enhanced green fluorescent protein-positive cells were negative for hematopoietic prostaglandin D synthase, but the number of hematopoietic prostaglandin D synthase-enhanced green fluorescent protein coexpressing cells increased significantly at 5-7 days after reperfusion. Our results indicate that hematopoietic prostaglandin D synthase is mainly produced by endogenous microglia until 72 h after reperfusion, but at 7 days after reperfusion, it is also produced by migrating bone marrow/blood-derived macrophages in the ischemic brain tissue. We speculate that hematopoietic prostaglandin D synthase in the brain has different functions during early and late phases of ischemia.

[Strategy for order-made treatment of diabetic macroangiopathy]

Several genetic risk factors such as single nucleotide polymorphisms(SNPs) in candidate genes have been reported to be responsible for diabetic macroangiopathy. We determined their genotypes regarding more than 100 SNPs in candidate genes responsible for average IMT of Japanese type 2 diabetic patients. We depicted some SNPs which were found to be significantly (p<0.05) responsible to the increase in AveIMT. Then, two combinations of double SNPs were evaluated as responsible for significant increases in AveIMT. Also, these two combinations were probably responsible for a high frequency of history of old myocardial infarction. The present analysis may provide one approach to evaluate combination of multiple genetic risk factors, which is synergistically associated with carotid atherosclerosis and myocardial infarction.

Combination of multiple genetic risk factors is synergistically associated with carotid atherosclerosis in Japanese subjects with type 2 diabetes

OBJECTIVE

Several genetic risk factors, such as single nucleotide polymorphisms (SNPs), in candidate genes have been reported to be responsible for intima-media thickness (IMT), which is one of the surrogate end points of cardiovascular events. However, the synergistic effects of SNPs have not been evaluated in detail.

RESEARCH DESIGN AND METHODS

We measured the average IMT of the common and internal carotid artery in Japanese type 2 diabetic patients (n = 690) (>50 years old) using ultrasonography. We also determined their genotypes regarding 106 SNPs in candidate genes responsible for cardiovascular diseases. Among the 106 SNPs, we selected 40 common (frequency of minor allele >/=10%) SNPs. We compared the average IMT of subjects with and without any pairs of four genotypes selected from the 40 common SNPs.

RESULTS

The combination of methylen-tetrahydrofolate reductase 677 TT genotype and lymphotoxin-alpha (LTA) 252 GG genotype and that of ACE DD genotype and LTA 252 GG genotype were evaluated as responsible for a statistically significant (P = 2.7 x 10(-9) and 3.5 x 10(-6), respectively) increase in average IMT (mean [+/-SD] 1.54 +/- 0.60 and 1.43 +/- 0.58 mm, respectively) compared with those of the subjects without these combinations (1.04 +/- 0.34 and 1.04 +/- 0.34 mm, respectively). No single genotype was shown to be responsible for the statistically significant difference in average IMT after Bonferroni's multiple comparison procedure.

CONCLUSIONS

The present analysis demonstrates an approach to evaluate combinations of multiple genetic risk factors that are synergistically associated with carotid atherosclerosis.

Marked increase of insulin gene transcription by suppression of the Rho/Rho-kinase pathway

The hallmarks of type 2 diabetes are pancreatic beta-cell dysfunction and insulin resistance. It has been suggested that Rho/Rho-kinase is a mediator of insulin signaling, and thereby involved in the development of insulin resistance, regulation of insulin action, and glucose homeostasis, but the role of Rho/Rho-kinase in beta-cells remained unknown. The aim of this study was to examine the possible role of Rho/Rho-kinase in beta-cell function. Immunostaining showed that RhoA was expressed in mature beta-cells, with higher expression observed in beta-cells of diabetic C57BL/KsJ-db/db mice compared to non-diabetic mice. In addition, to examine the functional role of Rho/Rho-kinase in beta-cells, we evaluated the effect of Rho-kinase inhibitors on insulin biosynthesis. Northern blot analysis showed that insulin mRNA levels were markedly increased by Rho-kinase inhibitors, Y-27632 and fasudil, in beta-cell-derived HIT-T15 cells. Furthermore, using the luciferase reporter gene assay, insulin promoter activity was also dramatically increased by Y-27632, which was associated with an increase in the insulin mRNA level. These results suggest that suppression of Rho/Rho-kinase increases insulin promoter activity, which leads to an increase in insulin mRNA level. Taken together, Rho/Rho-kinase is activated in beta-cells under diabetic conditions and suppression of the Rho/Rho-kinase pathway increases insulin gene transcription. These results imply that Rho/Rho-kinase activation is involved in the suppression of insulin expression found in diabetes and that suppression of the Rho/Rho-kinase pathway could be a useful tool to augment insulin gene transcription.

Recent Advances of Intervention to Inhibit Progression of Carotid Intima-Media Thickness in Patients With Type 2 Diabetes Mellitus

BACKGROUND AND PURPOSE

Type 2 diabetes is associated with a high cardiovascular morbidity and mortality. Recent advances of intervention studies in type 2 diabetes with use of carotid intima-media thickness (CIMT) measurement as a surrogate end point may allow for better understanding of the undetermined process of atherosclerosis, the effect of interventions, and the usefulness of CIMT to inhibit events of cardiovascular disease.

SUMMARY OF REVIEW

Data were available from 11 studies (n=1578) in subjects with type 2 diabetes (including impaired glucose tolerance, n=132) that evaluated the effect of interventions on change in CIMT. The overall weighed rate of change in mean CIMT based on data among control groups (ie, type 2 diabetes without interventions) was 0.034 mm/y (95% CI, 0.029 to 0.039; median SD, 0.054), in which mean HbA(1c) was 7.86% (95% CI, 7.72 to 8.00; median SD, 1.5). A significant close correlation of HbA(1c) with rate of CIMT change was found (R(2)=0.35, P=0.01). Agents for lowering of blood glucose, platelet activation, or blood pressure significantly reduced the CIMT increase, independent of blood glucose control. This implies that other mechanisms of such agents to diminish CIMT increase should be explored.

CONCLUSIONS

CIMT measurement may contribute to elucidating the short- and/or long-term effect of interventions on the rate of change in CIMT in relation to the levels of various risk factors. Although the method needs further standardization, pharmacological interventions are likely to inhibit progression of CIMT, leading to a reduction of cardiovascular events.

Rationale and protocol of a trial for prevention of diabetic atherosclerosis by using antiplatelet drugs: study of Diabetic Atherosclerosis Prevention by Cilostazol (DAPC study)

BACKGROUND

Secondary treatment of arteriosclerosis may be applicable for the primary prevention of atherosclerosis in diabetic patients. This prospective, 2-year follow-up study was designed to determine the efficacy and safety of antiplatelet therapy in the prevention of atherosclerosis of diabetic subjects.

METHODS

Patients with type 2 diabetes and arteriosclerosis obliterans from the Eastern Asian countries were registered online and randomly assigned either to the aspirin group (81-100 mg/day) or the cilostazol group (100-200 mg/day) in this international, 2-year, prospective follow-up interventional study.

RESULTS

The primary study endpoint was changes in right and left maximum intima-media thickness of the common carotid artery. Secondary endpoints include changes in right and left maximum intima-media thickness of the internal carotid artery; semiquantitative evaluation of cerebral infarction by magnetic resonance imaging; cardiovascular events including sudden death, stroke, transient cerebral ischemic attacks, acute myocardial infarction, angina, and progression of arteriosclerosis obliterans; overall death; withdrawal; and change in ankle-brachial pressure index.

CONCLUSION

This is the first study to use an online system that was developed in Asian countries for pooling data from an international clinical trial. These findings are expected to help in the prevention of diabetic atherosclerosis and subsequent cardiovascular and cerebrovascular disease.

Association of soluble CD40 ligand with carotid atherosclerosis in Japanese type 1 diabetic patients

AIMS/HYPOTHESIS

It has recently been shown that the soluble form of CD40 ligand (sCD40L) interacts with CD40 on vascular cells, leading to a variety of proinflammatory responses, and that serum sCD40L levels can be a predictive marker of cardiovascular events. The aim of this study was to estimate sCD40L levels in type 1 diabetic patients to examine a possible association with carotid atherosclerosis.

SUBJECTS AND METHODS

Human sCD40L levels in serum and intima-media thickness (IMT) of carotid artery were examined in 80 Japanese type 1 diabetic patients (27 men and 53 women, age 22.8+/-3.4 years (mean+/-SD), duration of diabetes 13.2+/-6.1 years) and 20 healthy age-matched non-diabetic individuals.

RESULTS

Serum sCD40L levels were significantly (p=0.0185) higher in subjects with type 1 diabetes (2.10+/-1.33 ng/ml) compared with non-diabetic subjects (1.35+/-0.88 ng/ml). The greatest IMT (Max-IMT) and averaged IMT (Mean-IMT) were also significantly greater in patients with type 1 diabetes than in control subjects (0.73+/-0.14 vs 0.64+/-0.07 mm, p=0.0041, 0.63+/-0.09 vs 0.57+/-0.06 mm, p=0.0066, respectively). Levels of sCD40L were statistically significantly associated with Max-IMT (r=0.383, p<0.001) and Mean-IMT (r=0.275, p=0.0058). Furthermore, stepwise multivariate regression analyses demonstrated that sCD40L is a determinant of both Max- and Mean-IMT, independently of conventional risk factors.

CONCLUSIONS/INTERPRETATION

It is suggested that increased levels of serum sCD40L are associated with accelerated atherosclerotic change observed in young patients with type 1 diabetes.

Persistent expression of PDX-1 in the pancreas causes acinar-to-ductal metaplasia through Stat3 activation

The transcription factor pancreatic and duodenal homeobox factor 1 (PDX-1) is expressed in pancreatic progenitor cells. In exocrine pancreas, PDX-1 is down-regulated during late development, while re-up-regulation of PDX-1 has been reported in pancreatic cancer and pancreatitis. To determine whether sustained expression of PDX-1 could affect pancreas development, PDX-1 was constitutively expressed in all pancreatic lineages by transgenic approaches. The transgenic pancreas was markedly small with the replacement of acinar cells by duct-like structures, accompanied by activated Stat3. Genetic ablation of Stat3 in the transgenic pancreas profoundly suppressed the metaplastic phenotype. These results provide a mechanism of pancreatic metaplasia by which persistent PDX-1 expression cell-autonomously induces acinar-to-ductal transition through Stat3 activation.