Plasma insulin in healthy subjects shows regular oscillations, which are important for the hypoglycemic action of the hormone. In individuals with type 2 diabetes, these regular variations are altered, which has been implicated in the development of insulin resistance and hyperglycemia. The origin of the change is unknown, but derangement of the islet secretory pattern has been suggested as a c...

INTRODUCTION Autotransplantation of isolated Langerhans islets is regarded as the only way to prevent iatrogenic diabetes in patients who had been scheduled for pancreatectomy due to painful chronic pancreatitis. A sufficient number of Langerhans islets capable of secretory activity need to be transplanted to maintain normoglycemia after the surgical procedure. In order to optimize all stages, ...

Chronic elevations in plasma levels of fatty acids (FAs) adversely affect pancreatic beta-cell function in type 2 diabetes. In vitro, we have previously shown that deleterious effects of prolonged exposure of isolated islets to FAs were dependent on the presence of elevated glucose concentration. This led us to hypothesize that both hyperlipidemia and hyperglycemia must be present simultaneousl...

Cyclo-oxygenase (COX), the enzyme responsible for conversion of arachidonic acid to prostanoids, exists as two isoforms. In most tissues, COX-1 is a constitutive enzyme involved in prostaglandin-mediated physiological processes, whereas COX-2 is thought to be induced by inflammatory stimuli. However, it has previously been reported that COX-2 is the dominant isoform in islets and an insulin-sec...

The cells within the intact islet of Langerhans function as a metabolic syncytium, secreting insulin in a coordinated and oscillatory manner in response to external fuel. With increased glucose, the oscillatory amplitude is enhanced, leading to the hypothesis that cells within the islet are secreting with greater synchronization. Consequently, non-insulin-dependent diabetes mellitus (NIDDM; typ...

Pancreas transportation between donor center and islet production facility is frequently associated with prolonged ischemia impairing islet isolation and transplantation outcomes. It is foreseeable that shipment of pig pancreases from distant centralized biosecure breeding facilities to institutes that have a long-term experience in porcine islet isolation is essentially required in future clin...

OBJECTIVE Ghrelin reportedly restricts insulin release in islet β-cells via the Gα(i2) subtype of G-proteins and thereby regulates glucose homeostasis. This study explored whether ghrelin regulates cAMP signaling and whether this regulation induces insulinostatic cascade in islet β-cells. RESEARCH DESIGN AND METHODS Insulin release was measured in rat perfused pancreas and isolated islets and...

Simultaneous stimulation of ex vivo pancreatic islets with dynamic oxygen and glucose is a critical technique for studying how hypoxia alters glucose-stimulated response, especially in transplant environments. Standard techniques using a hypoxic chamber cannot provide both oxygen and glucose modulations, while monitoring stimulus-secretion coupling factors in real-time. Using novel microfluidic...

Genotype/expression correlation in human pancreatic cDNAs. Isolated pancreatic islets were prepared by collagenase digestion and density gradient purification (1; 2). After isolation, islets were cultured free-floating in M199 culture medium (Sigma-Aldrich) at 5.5 mmol/l glucose concentration. Within 3 days of isolation, the islets were used for RNA extraction. Total RNA was extracted from the ...

Chronic pancreatitis is an inflammatory disease of the pancreas that causes permanent changes in the function and structure of the pancreas. It is most commonly a complication of cystic fibrosis or due to a genetic predisposition. Chronic pancreatitis generally presents symptomatically as recurrent abdominal pain, which becomes persistent over time. The pain eventually becomes disabling. Once s...