A 37-residue peptide hormone.

It is cosecreted with insulin from the pancreatic β-cells in the ratio of approximately 100:1.

Amylin plays a role in glycemic regulation by slowing gastric emptying and promoting satiety, thereby preventing post-prandial spikes in blood glucose levels.

European researchers tend to prefer IAPP whereas American researchers tend to prefer amylin.

Produced in the pancreatic beta cells (β-cells) as a 67 amino acid, 7404 Dalton pro-peptide and undergoes post-translational modifications including protease cleavage to produce amylin.

It undergoes additional proteolysis and posttranslational modification from the precursor protein proIAPP to the biologically active IAPP.

Insulin and IAPP are regulated by similar factors.

The IAPP promoter is also activated by stimuli which do not affect insulin, such as tumor necrosis factor alpha and fatty acids.

In Type 2 diabetes insulin resistance occurs, resulting in increased insulin production and since proinsulin and proIAPP are cosecreted, this results in an increase in the production of proIAPP as well.

Regulatory mechanisms that affect insulin also affect IAPP.

Blood glucose levels play an important role in regulation of proIAPP synthesis.

Amylin functions as part of the endocrine pancreas and contributes to glycemic control.

The amylin peptide is secreted from the pancreatic islets into the blood circulation and is cleared by peptidases in the kidney.

Amylin is not found in the urine.

Functions as a synergistic partner to insulin.

It is cosecreted from pancreatic beta cells in response to meals.

Its overall effect is to slow the rate of appearance of glucose in the blood after eating, by slowing down gastric emptying, inhibition of digestive secretion and a resulting reduction in food intake.

Appearance of glucose in the blood is reduced by inhibiting secretion of the gluconeogenic hormone glucagon.

These actions, which are mostly carried out via a glucose-sensitive part of the brain stem, the area postrema, collectively reduce the total insulin demand.

Amylin also acts in bone metabolism.

Linked to Type 2 diabetes and the loss of islet β-cells.

Islet amyloid formation may contribute to this progressive loss of islet β-cells.

It is thought that proIAPP forms the first granules that allow for IAPP to aggregate and form amyloid which may lead to amyloid-induced apoptosis of β-cells.

IAPP is cosecreted with insulin.

Insulin resistance in Type 2 diabetes produces a greater demand for insulin production which results in the secretion of proinsulin.

ProIAPP is secreted simultaneously, however, the enzymes that convert these precursor molecules into insulin and IAPP, respectively, are not able to keep up with the high levels of secretion, ultimately leading to the accumulation of proIAPP.

Impaired processing of proIAPP that occurs at the N-terminal cleavage site is a key factor in the initiation of amyloid.

The conditions of Type 2 diabetes―high glucose concentrations and increased secretory demand for insulin and IAPP―could lead to the impaired N-terminal processing of proIAPP.

Unprocessed proIAPP can then serve as the granule upon which IAPP can accumulate and form amyloid.

The amyloid formation might be a major mediator of apoptosis, or programmed cell death, in the islet β-cells.

ProIAPP aggregates within secretory vesicles inside the cell and acts as a seed, collecting matured IAPP within the vesicles, forming intracellular amyloid.

Impaired N-terminal processing of proIAPP helps initiate amyloid formation and β-cell death.

Amyloid deposits are a characteristic of the pancreas in Type 2 diabetes.

Amyloid formation reduces working β-cells in patients with Type 2 diabetes.

Repairing proIAPP processing may help to prevent β-cell death, thereby offering hope as a potential therapeutic approach for Type 2 diabetes.

Amyloid deposits deriving from islet amyloid polypeptide (IAPP, or amylin) are commonly found in pancreatic islets of patients suffering diabetes mellitus type 2, or containing an insulinoma.

A synthetic analog of human amylin with proline substitutions in positions 25, 26 and 29, or pramlintide for adult use in patients with both diabetes mellitus type 1 and diabetes mellitus type 2.

Insulin and pramlintide, injected separately but both before a meal, work together to control the post-prandial glucose excursion.

Amylin is degraded in part by insulin-degrading enzyme.

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