Nicotinic Acid GPCR Family Subtypes and Products

What Are Nicotinic Acid Receptors?

Nicotinic acid receptors, also known as hydroxycarboxylic acid (HCA) receptors, are a family of G protein-coupled receptors (GPCRs) comprised of three receptor subtypes: HCA1, HCA2, and HCA3. These receptors play a role in the modulation of antilipolytic effects within fat cells. While HCA1 and HCA2 are present in most mammals, only higher primates possess HCA3 receptors. Research is being done into the potential of HCA receptors as anti-inflammatory treatments.

Nicotinic Acid Receptor Information

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GPR109A

GPR109B

GPR81

GPR109A (HM74A, PUMA-G or niacin receptor 1) is a high-affinity receptor for nicotinic acid (niacin), and is highly expressed in adipocytes, lung, macrophages, dendritic cells, microglia and neutrophils. GPR109A in adipocytes is likely to be involved in niacin- mediated inhibition of lipolysis, reduction of serum free fatty acids and triglycerides as well as elevation of high density lipoproteins. GPR109A also serves important functions in the immune system. GPR109A on Langerhans cells in the skin also mediates niacin-induced cutaneous flushing, one of the major side effects of niacin, via the massive production of prostaglandins PGD2 and PGE2 in a ligand-dependent fashion.

GPR109B (or HM74) is a 387-amino acid, 7-transmembrane protein responsible for the directed migration of specific cell types. GPR109B has highest expression in spleen, lymphocytes and adipose tissue, and lower expression in the heart, placenta, prostate and bone marrow. Nicotinic acid has been used as a lipid-lowering agent possibly by acting through GPR109A and GPR109B in adipose tissues. This supports the suggestion that signaling through this nicotinic acid receptors may be a mechanism for the treatment of hyperlipidemia and insulin-resistant states.

GPR81 is an orphan G protein-coupled receptor homologous to GPR109A and GPR109B. It is highly expressed in adipose tissues and also regarded as a sensor for Lactate and can mediate an anti-lipolytic effect of lactate. GPR81 can modulate the free fatty acid pool under exercise or conditions of oxygen deficit and is target for the treatment of dyslipidemia and other metabolic disorders.

Nicotinic Acid Cell Lines

Receptor FamilyReceptorSpeciesParentalStable Cell Lines Division-Arrested Cells Membranes
Nicotinic AcidGPR109AhumanCHO-K1C1370-1DC1370-1MC1370-1
GPR109BhumanCHO-K1C1059-1DC1059-1MC1059-1
GPR81humanHEK293TC1134DC1134MC1134