G protein-coupled receptor 32, also known as GPR32 or the RvD1 receptor, is a human receptor (biochemistry) belonging to the rhodopsin-like subfamily of G protein-coupled receptors. [3]
G protein-coupled receptor 32, also known as GPR32 or the RvD1 receptor, is a human receptor (biochemistry) belonging to the rhodopsin-like subfamily of G protein-coupled receptors. [3]
The GPR32 was initially identified and defined by molecular cloning in 1998 as coding for an orphan receptor, i.e. a protein with an amino acid sequence similar to known receptors but having no known ligand(s) to which it responds and no known function. The projected amino acid sequence of GPR32, however, shared 35-39% amino acid identity with certain members of the chemotactic factor receptor family, i.e. 39% identity with Formyl peptide receptor 1, which is a receptor for N-Formylmethionine-leucyl-phenylalanine and related N-formyl peptide chemotactic factors, and 35% identity with Formyl peptide receptor 2, which likewise is also a receptor for N-formyl peptides but also a receptor for certain lipoxins which are arachidonic acid metabolites belonging to a set of specialized proresolving mediators that act to resolve or inhibit inflammatory reactions. GPR32 mapped to chromosomal 19, region q13.3. [4] There are no mouse or other orthologs of GPR32. [5]
The GPR32 protein is a G protein coupled receptor although the specific G protein subtypes which it activates has not yet been reported. GPR32 is expressed in human blood neutrophils, certain types of blood lymphocytes (i.e. activated CD8+ cells, CD4+ T cells, and T helper 17 cells), tissue macrophages, small airway epithelial cells, and adipose tissue. [5] [6] [7] When expressed in Chinese hamster ovary cells, GPR32 inhibits the Cyclic adenosine monophosphate signaling pathway under both baseline and forskolin-stimulated conditions indicating that it is a member of the class of orphan G protein coupled receptors that possesses constitutive signaling activity. [8]
At least 6 members of the D series of resolvins (RvDs) viz., RvD1, RvD2m AT-RVD1, RvD3, AT-RvD3, and RvD5, activate their target cells through this receptor; these results have led to naming GPR32 the RVD1 receptor (see resolvin mechanisms of action). [9] [10] [11] RvDs are members of the specialized proresolving mediators (SPM) class of polyunsaturated fatty acid metabolites. RVDs are metabolites of the omega-3 fatty acid, docosahexaenoic acid (DHA), and, along with other SRMs contribute to the inhibition and resolution of a diverse range of inflammation and inflammation-related responses as well as to the healing of these inflammatory lesions in animals and humans. [12] The metabolism of DHA to RVD's and the activation of GPR32 by these RVD's are proposed to be one mechanism by which omega-3 fatty acids may ameliorate inflammation as well as various inflammation-based and other diseases. [13]
A lipoxin (LX or Lx), an acronym for lipoxygenase interaction product, is a bioactive autacoid metabolite of arachidonic acid made by various cell types. They are categorized as nonclassic eicosanoids and members of the specialized pro-resolving mediators (SPMs) family of polyunsaturated fatty acid (PUFA) metabolites. Like other SPMs, LXs form during, and then act to resolve, inflammatory responses. Initially, two lipoxins were identified, lipoxin A4 (LXA4) and LXB4, but more recent studies have identified epimers of these two LXs: the epi-lipoxins, 15-epi-LXA4 and 15-epi-LXB4 respectively.
Resolvins are specialized pro-resolving mediators (SPMs) derived from omega-3 fatty acids, primarily eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), as well as docosapentaenoic acid (DPA) and clupanodonic acid. As autacoids similar to hormones acting on local tissues, resolvins are under preliminary research for their involvement in promoting restoration of normal cellular function following the inflammation that occurs after tissue injury. Resolvins belong to a class of polyunsaturated fatty acid (PUFA) metabolites termed specialized proresolving mediators (SPMs).
Docosapentaenoic acid (DPA) designates any straight chain 22:5 fatty acid, that is a straight chain open chain type of polyunsaturated fatty acid (PUFA) which contains 22 carbons and 5 double bonds. DPA is primarily used to designate two isomers, all-cis-4,7,10,13,16-docosapentaenoic acid and all-cis-7,10,13,16,19-docosapentaenoic acid. They are also commonly termed n-6 DPA and n-3 DPA, respectively; these designations describes the position of the double bond being 6 or 3 carbons closest to the (omega) carbon at the methyl end of the molecule and is based on the biologically important difference that n-6 and n-3 PUFA are separate PUFA classes, i.e. the omega-6 fatty acids and omega-3 fatty acids, respectively. Mammals, including humans, can not interconvert these two classes and therefore must obtain dietary essential PUFA fatty acids from both classes in order to maintain normal health.
The transient receptor potential cation channel subfamily V member 1 (TrpV1), also known as the capsaicin receptor and the vanilloid receptor 1, is a protein that, in humans, is encoded by the TRPV1 gene. It was the first isolated member of the transient receptor potential vanilloid receptor proteins that in turn are a sub-family of the transient receptor potential protein group. This protein is a member of the TRPV group of transient receptor potential family of ion channels.
Most of the eicosanoid receptors are integral membrane protein G protein-coupled receptors (GPCRs) that bind and respond to eicosanoid signaling molecules. Eicosanoids are rapidly metabolized to inactive products and therefore are short-lived. Accordingly, the eicosanoid-receptor interaction is typically limited to a local interaction: cells, upon stimulation, metabolize arachidonic acid to an eicosanoid which then binds cognate receptors on either its parent cell or on nearby cells to trigger functional responses within a restricted tissue area, e.g. an inflammatory response to an invading pathogen. In some cases, however, the synthesized eicosanoid travels through the blood to trigger systemic or coordinated tissue responses, e.g. prostaglandin (PG) E2 released locally travels to the hypothalamus to trigger a febrile reaction. An example of a non-GPCR receptor that binds many eicosanoids is the PPAR-γ nuclear receptor.
Arachidonate 5-lipoxygenase, also known as ALOX5, 5-lipoxygenase, 5-LOX, or 5-LO, is a non-heme iron-containing enzyme that in humans is encoded by the ALOX5 gene. Arachidonate 5-lipoxygenase is a member of the lipoxygenase family of enzymes. It transforms essential fatty acids (EFA) substrates into leukotrienes as well as a wide range of other biologically active products. ALOX5 is a current target for pharmaceutical intervention in a number of diseases.
Transient receptor potential cation channel, subfamily A, member 1, also known as transient receptor potential ankyrin 1, TRPA1, or The Wasabi Receptor, is a protein that in humans is encoded by the TRPA1 gene.
Transient receptor potential cation channel subfamily V member 4 is an ion channel protein that in humans is encoded by the TRPV4 gene.
Transient receptor potential cation channel, subfamily V, member 3, also known as TRPV3, is a human gene encoding the protein of the same name.
In biochemistry, docosanoids are signaling molecules made by the metabolism of twenty-two-carbon fatty acids (EFAs), especially the omega-3 fatty acid, Docosahexaenoic acid (DHA) by lipoxygenase, cyclooxygenase, and cytochrome P450 enzymes. Other docosanoids are metabolites of n-3 docosapentaenoic acid, n-6 DHA (i.e. 4Z,7Z,10Z,13Z,16Z-docosahexaenoic acid, and docosatetraenoic acid. Prominent docosanoid metabolites of DHA and n-3 DHA are members of the specialized proresolving mediator class of polyunsaturated fatty acid metabolites that possess potent anti-inflammation, tissue healing, and other activities.
Neuroprotectin D1 (NPD1) also known as Protectin D1 (PD1) is a docosanoid derived from the polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA), which is a component of fish oil and the most important omega-3 PUFA. Like other members of the specialized proresolving mediators class of PUFA metabolites, NPD1 exerts potent anti-inflammatory and anti-apoptotic/neuroprotective bioactivity. Other neuroprotectins with similar activity include: PDX ; 20-hydroxy-PD1 ; and 10-epi-PD1. The activity of neuroprotectin-like metabolite, 17-epi-PD1, has not yet been reported.
ALOX15 is, like other lipoxygenases, a seminal enzyme in the metabolism of polyunsaturated fatty acids to a wide range of physiologically and pathologically important products. ▼ Gene Function
N-formyl peptide receptor 2 (FPR2) is a G-protein coupled receptor (GPCR) located on the surface of many cell types of various animal species. The human receptor protein is encoded by the FPR2 gene and is activated to regulate cell function by binding any one of a wide variety of ligands including not only certain N-Formylmethionine-containing oligopeptides such as N-Formylmethionine-leucyl-phenylalanine (FMLP) but also the polyunsaturated fatty acid metabolite of arachidonic acid, lipoxin A4 (LXA4). Because of its interaction with lipoxin A4, FPR2 is also commonly named the ALX/FPR2 or just ALX receptor.
Chemokine like receptor 1 also known as ChemR23 is a protein that in humans is encoded by the CMKLR1 gene. Chemokine receptor-like 1 is a G protein-coupled receptor for the chemoattractant adipokine chemerin and the omega-3 fatty acid eicosapentaenoic acid-derived specialized pro-resolving molecule, resolvin E1. The murine receptor that shares almost 80% homology with the human receptor, is called Dez.
N-formyl peptide receptor 3 (FPR3) is a receptor protein that in humans is encoded by the FPR3 gene.
N-Arachidonyl glycine receptor, also known as G protein-coupled receptor 18 (GPR18), is a protein that in humans is encoded by the GPR18 gene. Along with the other previously "orphan" receptors GPR55 and GPR119, GPR18 has been found to be a receptor for endogenous lipid neurotransmitters, several of which also bind to cannabinoid receptors. It has been found to be involved in the regulation of intraocular pressure.
G-protein coupled receptor 120 is a protein that in humans is encoded by the GPR120 gene.
Maresin 1 (MaR1 or 7R,14S-dihydroxy-4Z,8E,10E,12Z,16Z,19Z-docosahexaenoic acid) is a macrophage-derived mediator of inflammation resolution coined from macrophage mediator in resolving inflammation. Maresin 1, and more recently defined maresins, are 12-lipoxygenase-derived metabolites of the omega-3 fatty acid, docosahexaenoic acid (DHA), that possess potent anti-inflammatory, pro-resolving, protective, and pro-healing properties similar to a variety of other members of the specialized proresolving mediators (SPM) class of polyunsaturated fatty acid (PUFA) metabolites. SPM are dihydroxy, trihydroxy, and epoxy-hydroxy metabolites of long chain PUFA made by certain dioxygenase enzymes viz., cyclooxygenases and lipoxygenases. In addition to the maresins, this class of mediators includes: the 15-lipoxygenase (i.e. ALOX15 and/or possibly ALOX15B)-derived Lipoxin A4 and B4 metabolites of the omega 6 fatty acid, arachidonic acid; the cyclooxygenase 2-derived Resolvin E series metabolites of the omega 3 fatty acid, eicosapentaenoic acid; certain 15-lipoxygenase-derived Resolvin D series metabolites of DHA; certain other 15-lipoxygenase-derived protectin D1 and related metabolites of DHA; and the more recently defined and therefore less fully studied 15-lipoxygenase-derived Resolvin Dn-3DPA metabolites of the omega-3 fatty acid n-3 docosapentaenoic acid (n-3 DPA or clupanodonic acid), the cyclooxygenase 2-derived Resolvin T metabolites of this clupanodonic acid, and the 15-lipoxygenase-derived products of the N-acetylated fatty acid amide of the DHA metabolite, docosahexaenoyl ethanolamide (see resolvins).
Protectin D1 also known as neuroprotectin D1 and abbreviated most commonly as PD1 or NPD1 is a member of the class of specialized proresolving mediators. Like other members of this class of polyunsaturated fatty acid metabolites, it possesses strong anti-inflammatory, anti-apoptotic and neuroprotective activity. PD1 is an aliphatic acyclic alkene 22 carbons in length with two hydroxyl groups at the 10 and 17 carbon positions and one carboxylic acid group at the one carbon position.
Specialized pro-resolving mediators are a large and growing class of cell signaling molecules formed in cells by the metabolism of polyunsaturated fatty acids (PUFA) by one or a combination of lipoxygenase, cyclooxygenase, and cytochrome P450 monooxygenase enzymes. Pre-clinical studies, primarily in animal models and human tissues, implicate SPM in orchestrating the resolution of inflammation. Prominent members include the resolvins and protectins.
 | This transmembrane receptor-related article is a stub. You can help Wikipedia by expanding it. |