Cortistatin (neuropeptide)

Cortistatin is a neuropeptide that shares significant structural and functional similarities with somatostatin. It was first discovered in the human brain and has since been identified in other tissues. Cortistatin is involved in various physiological processes, including sleep regulation, hormone secretion, and immune response.

Structure and Function

Cortistatin is a 29-amino acid peptide that is produced by alternative splicing of the prepro-cortistatin gene. It shares 11 of its 14 residues with somatostatin, a hormone that inhibits the release of several other hormones. Despite their similarities, cortistatin and somatostatin have distinct functions due to their different distribution in tissues and their interaction with different receptors.

Cortistatin binds to all five known somatostatin receptors (sst1-5) and has a higher affinity for the ghrelin receptor, also known as the growth hormone secretagogue receptor (GHS-R). This binding activity allows cortistatin to exert a wide range of effects on the body.

Physiological Roles

Sleep Regulation

Cortistatin is primarily known for its role in sleep regulation. It is produced in the hypothalamus, a region of the brain that controls sleep and wakefulness. Cortistatin promotes slow-wave or non-rapid eye movement (NREM) sleep and inhibits rapid eye movement (REM) sleep. It also reduces brain temperature and metabolic activity, further promoting sleep.

Hormone Secretion

Cortistatin also plays a role in hormone secretion. It inhibits the release of growth hormone, thyroid-stimulating hormone, and prolactin from the pituitary gland. It also suppresses the release of insulin from the pancreas and glucagon from the liver, helping to regulate blood glucose levels.

Immune Response

Cortistatin has anti-inflammatory properties and can modulate the immune response. It inhibits the production of pro-inflammatory cytokines and promotes the production of anti-inflammatory cytokines. This makes cortistatin a potential therapeutic target for inflammatory and autoimmune diseases.

Clinical Significance

Due to its diverse physiological roles, cortistatin has been implicated in several diseases, including sleep disorders, endocrine disorders, and inflammatory diseases. It may also have potential as a therapeutic target for these conditions.

See Also

• Neuropeptide
• Somatostatin
• Hypothalamus
• Pituitary gland