Pathologic changes and glucose homeostasis according to expression of human islet amyloid polypeptide in type 2 diabetic patients.

The amount of amyloid detectable in islets varies, and is not always correlated with degree of beta-cell loss. It has been hypothesized that islet amyloid polypeptide (IAPP) aggregation causes beta-cell dysfunction. In this study, we investigated the relationship between IAPP expression and glucose homeostasis in pancreatectomized patients.

Enhancement of beta-cell regeneration by islet transplantation after partial pancreatectomy in mice.

Background: Pancreatic beta cells are known to regenerate, especially when insulin requirements are increased. Islet transplantation (ITx) is one strategy for insulin replacement in patients with diabetes. ITx can provide not only insulin in a physiological manner but also can exert additional effects such as beta-cell regeneration.

Delayed improvement of insulin secretion after autologous islet transplantation in partially pancreatectomized patients.

The purpose of this study was to evaluate the effects of autologous islet transplantation (ITx) on glucose homeostasis and insulin secretory function after partial pancreatectomy (Px). Fourteen nondiabetic patients who underwent distal Px and autologous ITx for benign pancreatic tumors were enrolled in the study (Px + ITx group). Fourteen normal glucose-tolerant controls and 6 Px without ITx controls were recruited, and all groups were followed over a 24-month period.

Antiobesity effects and improvement of insulin sensitivity by 1-deoxynojirimycin in animal models.

The alpha-glucosidase inhibitor 1-deoxynojirimycin (DNJ) is one of the simplest naturally occurring carbohydrate mimics, with promising biological activity in vivo. Although there is considerable interest in the pharmacological effects of DNJ, the antidiabetic effects of DNJ in type 2 diabetes mellitus have received little attention. In this work, DNJ was isolated from the silkworm (Bombyx mori), and its antidiabetic effects were evaluated in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, an established animal model of human type 2 diabetes mellitus, and in control Long-Evans Tokushima Otsuka (LETO) rats.

A better yield of islet cell mass from living pancreatic donors compared with cadaveric donors.

Studies in rats have shown that brain death decreases beta-cell function and causes islet cell death during islet isolation and transplantation. Because a direct comparison of human islet cells between living and cadaveric donors has not been reported to date, we studied the effects of brain death on islet cell yield. A total of 36 pancreas specimens from 20 living donors and 16 cadaveric donors were used for analysis.

Effective glycemic control achieved by transplanting non-viral cationic liposome-mediated VEGF-transfected islets in streptozotocin-induced diabetic mice.

Hypoxic damage is one of the major causes of islet graft failure and VEGF is known to play a crucial role in revascularization. To address the effectiveness of a cationic lipid reagent as a VEGF gene carrier, and the beneficial effect of VEGF-transfected islets on glycemic control, we used effectene lipid reagent in a transfection experiment using mouse islets. Transfection efficiencies were highest for 4 microg/microgL cDNA and 25 microgL effectene and cell viabilities were also satisfactory under this condition, and the overproduction of VEGF mRNA and protein were confirmed from conditioned cells.

The favorable outcome of human islet transplantation in Korea: experiences of 10 autologous transplantations.

Background: Cystic neoplasms of the pancreas are an increasingly diagnosed entity, and surgical resection of the pancreas is advocated. Islet autotransplantation is a therapeutic approach used to prevent diabetes in cases of pathologically benign neoplasm after major pancreatectomy.

Methods: A total of 10 patients underwent pancreatectomy with islet autotransplantation.