Effect of osteocalcin on human beta cell proliferation and function and its role on insulin secretion

s / Pancreatology 13 (2013) S2–S98 S64 the test cohorts and lack of a standard reference method, more studies are needed to conclude that the trypsinmethod is superior. We are developing a reference method using confocal microscopy. PII-36 Abstract id: 17. Effect of osteocalcin on human beta cell proliferation and function and its role on insulin secretion Anita Kaw, Daniel Fraga, Craig Fischer. The Methodist Hospital Research Institute, Houston, Texas, United States Introduction: Osteocalcin, a hormone produced by bone cells, has been found to increase insulin production, enhance insulin sensitivity, and promote b-cell proliferation in mouse models, however most mouse studies do not reliably affect humans in the same manner. Aims: This study sought to confirm the effect of osteocalcin on human b-cell proliferation and function and its role, if any, on insulin secretion. Materials & methods: Three variants of osteocalcin extracted and purified from bovine tibial cortical bone were investigated: osteocalcin (OC), decarboxylated osteocalcin (D-OC), and osteocalcin hexapeptide (HOC) were utilized in conjunction with a well-established islet model. Protocol included human pancreatic islet isolation from brain dead donors, islet cell culture in Memphis serum free mediumwith heparin, assessment of islet viability with flow cytometry, insulin secretion and content in vitro with western blot analysis and analysis of cellular composition by immunofluorescence. Results: Our results indicate that after 7 days in culture all three types of osteocalcin improved insulin-content and b-cell proliferation of glucose-stimulated islets, with D-OC showing the most significant and dose-dependent effect. The greatest effect on insulin enhancement was noted at the earliest time point (7 days), and this effect progressively deteriorated at later time points, reflecting perhaps senescence in our culture while apoptosis was not impacted by either osteocalcin or time in culture. Conclusion: Our findings indicate that osteocalcin or one of its variants may be utilized in patients whose disease conditions show a progressive loss of b-cell mass and function namely type 2 and, in some cases type 1 diabetes. PII-37 Abstract id: 226. Impact of pancreatic enzymes on blood glucose and insulin release in a porcine model Liudmyla Lozinska, Olena Prykhod’ko, Katarzyna Szwiec, Bj€ orn Westr€ om, Stefan Pierzynowski. Lund University, Dept Biology, Sweden Introduction: Exocrine pancreatic insufficiency (EPI) induced in young pigs by pancreatic duct ligation (PDL) results in growth arrest and a decreased ability to retain/assimilate nutrients. Aims: The aim of the study was to explore the effects of pancreatic enzyme replacement therapy (PERT) on glucose utilization and insulin secretion in this model. Materials & methods: Five EPI pigs and six control pigs were studied andmeal (MGTT), oral (OGTT), and i.v. glucose tolerance tests (IVGTT) were performed, either with or without PERT (Creon 10,000). Blood glucose was measured with a glucose-meter and plasma insulin using an ELISA kit. Results: The MGTT resulted in increased plasma glucose levels similar to that in the controls, but only a negligible increase in insulin levels. The MGTT following PERT, resulted in a prolonged increase in blood glucose (above those in controls) and insulin (below that in controls) levels. The OGTT, both with and without PERT, caused a prolonged increase in blood glucose levels compared to controls. A parallel increase in insulin levels were observed, however the increase was smaller in comparison to the controls. PERT before IVGTT, accelerated the elimination of glucose and at the same time lowered the insulin levels, with a shift in the curve peak towards that observed in the controls. Conclusion: In conclusion, the data indicates that pancreatic enzymes not only affect the availability of glucose from the food, but also affect the post-prandial insulin response in line with the incretin concept and thus suggests a factor released in response to PERT which affects glucose utilization. PII-38 Abstract id: 177. Pancreatic and pancreatic-like enzymes decrease insulin secretion together with an enhanced insulin efficiency or provoke insulin-independent glucose utilisation Olena Prykhodko, Liudmyla Lozinska, Katarzyna Szwiec, Adam Lada, Olexandr Fedkiv, Bj€ orn Westr€ om, Stefan Pierzynowski. Dept of Biology, Lund University, Sweden Introduction: The role of the exocrine pancreas in food digestion is well-studied but its’ possible (para-digestive) effects on insulin release and glucose tolerance has received less attention. Aims: We aimed to study the effects of pancreatic enzyme supplementation on blood glucose and plasma insulin in normal pigs. Materials & methods: Twelve pigs, 2.5 months old, were fasted overnight and then administered either porcine enzymes (Creon 10 000) or a mixture of pancreatic-like enzymes of microbial origin (PLEM), or empty capsules as a placebo. After 1h an intravenous glucose tolerance test (IVGTT) was performed (by infusion of 1g glucose/kg, using 50% solution). Repeated blood samples were taken and blood glucose was measured with a glucose-meter and plasma insulin levels with an ELISA-kit. Results: Blood glucose decreased 1h after enzyme administration (12.8% for Creon, 15.5% for PLEM, p<0.05), while placebo had no influence. Surprisingly, after enzyme feeding insulin levels also decreased to 3-times less than the baseline. The IVGTT showed a similar slope of glucose elimination/utilization in enzyme-supplemented and control pigs, while insulin levels were significantly lower in enzyme-fed pigs as seen after 15 and 30 min after i.v. glucose infusion. Conclusion: The data indicate that administration of pancreatic and pancreatic-like enzymes reduce insulin release and enhance the glucose tolerance. The results suggest also a para-digestive, insulin-like anabolic action on glucose utilisation via unidentified factor(s) released in response to the enzymes supplementation. The findings might have impact on todays increased obesity problem related to an enhanced exocrine secretion due to increased carbohydrate consumption. PII-39 Abstract id: 113. Modulation of pancreatic amylase secretion by tryptophan metabolite Katarzyna Nawrot-Porabka, Anna Leja-Szpak, Joanna Szklarczyk, Martyna Kosiba, Jolanta Jaworek. Department of Medical Physiology Faculty of Health Sciences, School of Medicine Jagiellonian University, Cracow, Poland Introduction: The kynurenines, products of tryptophan metabolism, are involved in many physiological processes as well as in regulation of the immune response of the organism. These products have been detected within gastrointestinal system, but their effects on pancreatic amylase secretion have not been investigated yet. Aims: To assess the effects of intraduodenal (i.d.) infusion of L-kynurenine on pancreatic amylase outputs under basal conditions and following the stimulation of pancreatic secretion with diversion of pancreato-biliary juice (DPBJ) and the role of CCK in that process.