Misplaced Pages

Orosomucoid (ORM) or alpha-1-acid glycoprotein (α₁AGp, AGP or AAG) is an acute phase protein found in plasma. It is an alpha-globulin glycoprotein and is modulated by two polymorphic genes. It is synthesized primarily in hepatocytes and has a normal plasma concentration between 0.6–1.2 mg/mL (1–3% plasma protein). Plasma levels are affected by pregnancy, burns, certain drugs, and certain diseases, particularly HIV.

The only established function of ORM is to act as a carrier of basic and neutrally charged lipophilic compounds. In medicine, it is known as the primary carrier of basic (positively charged) drugs (whereas albumin carries acidic (negatively charged) and neutral drugs), steroids, and protease inhibitors. Aging causes a small decrease in plasma albumin levels; if anything, there is a small increase in alpha-1-acid glycoprotein. The effect of these changes on drug protein binding and drug delivery, however, appear to be minimal. AGP shows a complex interaction with thyroid homeostasis: AGP in low concentrations was observed to stimulate the thyrotropin (TSH) receptor and intracellular accumulation of cyclic AMP. High AGP concentrations, however, inhibited TSH signalling.

Alpha-1-acid glycoprotein has been identified as one of four potentially useful circulating biomarkers for estimating the five-year risk of all-cause mortality (the other three are albumin, very low-density lipoprotein particle size, and citrate).

Orosomucoid increases in amount in obstructive jaundice while it diminishes in hepatocellular jaundice and in intestinal infections.

See also

• Alpha-1 antitrypsin deficiency
• Alpha-1 antitrypsin

References

1. Logan, Carolynn M.; Rice, M. Katherine (1987). Logan's Medical and Scientific Abbreviations. Philadelphia: J. B. Lippincott Company. p. 3. ISBN 0-397-54589-4.
2. ^ Colombo S, Buclin T, Décosterd LA, Telenti A, Furrer H, Lee BL, Biollaz J, Eap CB (October 2006). "Orosomucoid (alpha1-acid glycoprotein) plasma concentration and genetic variants: effects on human immunodeficiency virus protease inhibitor clearance and cellular accumulation". Clinical Pharmacology and Therapeutics. 80 (4): 307–18. doi:10.1016/j.clpt.2006.06.006. PMID 17015049. S2CID 684478.
3. Urien S, Brée F, Testa B, Tillement JP (November 1991). "pH-dependency of basic ligand binding to alpha 1-acid glycoprotein (orosomucoid)". The Biochemical Journal. 280 ( Pt 1) (1): 277–80. doi:10.1042/bj2800277. PMC 1130632. PMID 1741754.
4. Rooke GA (2009). "Anesthesia for the Older Patient". In Barash PG, Cullen BF, Stoelting RK, Cahalan MK, Stock MC (eds.). Clinical Anesthesia. Lippincott Williams & Wilkins. p. 879. ISBN 978-0-7817-8763-5.
5. Zimmermann-Belsing T, Rasmussen AK, Feldt-Rasmussen U, Bøg-Hansen TC (February 2002). "The influence of alpha1-acid glycoprotein (orosomucoid) and its glycoforms on the function of human thyrocytes and CHO cells transfected with the human TSH receptor". Molecular and Cellular Endocrinology. 188 (1–2): 241–51. doi:10.1016/s0303-7207(01)00650-5. PMID 11911961. S2CID 22815279.
6. Dietrich JW, Landgrafe G, Fotiadou EH (2012). "TSH and Thyrotropic Agonists: Key Actors in Thyroid Homeostasis". Journal of Thyroid Research. 2012: 351864. doi:10.1155/2012/351864. PMC 3544290. PMID 23365787.
7. Fischer K, Kettunen J, Würtz P, Haller T, Havulinna AS, Kangas AJ, Soininen P, Esko T, Tammesoo ML, Mägi R, Smit S, Palotie A, Ripatti S, Salomaa V, Ala-Korpela M, Perola M, Metspalu A (February 2014). "Biomarker profiling by nuclear magnetic resonance spectroscopy for the prediction of all-cause mortality: an observational study of 17,345 persons". PLOS Medicine. 11 (2): e1001606. doi:10.1371/journal.pmed.1001606. PMC 3934819. PMID 24586121.

External links

• Orosomucoid at the U.S. National Library of Medicine Medical Subject Headings (MeSH)

This article on a gene on human chromosome 9 is a stub. You can help Misplaced Pages by expanding it.

• v
• t
• e

• Genes on human chromosome 9
• Acute-phase proteins
• Glycoproteins
• Molecular biology
• Proteomics
• Human chromosome 9 gene stubs