GPR-44 Activators

GPR-44 include a range of compounds that can influence the receptor's activity through various signaling mechanisms. Prostaglandin D2 is a primary activator, engaging directly with GPR-44 and initiating a cascade of intracellular events through G-protein mediated pathways, predominantly involving Gq proteins, which lead to increased intracellular calcium levels. Similarly, treprostinil, though not directly targeting GPR-44, can elevate cAMP within cells, which then activates protein kinase A (PKA). PKA, in turn, promotes the phosphorylation of proteins that may include GPR-44, thus enhancing its activity. Misoprostol, although primarily interacting with prostaglandin E receptors, can also engage GPR-44 activity due to the interconnectedness of prostaglandin signaling pathways and the synthesis of inflammatory mediators that can activate the receptor.

Further down the list, iloprost and beraprost, both analogs of prostacyclin, bind to their respective receptors and lead to increased cAMP production. This surge in cAMP can similarly activate PKA, which may phosphorylate and activate GPR-44. Butaprost, an agonist for the EP2 receptor subtype, increases cAMP levels within the cell, again potentially activating PKA and subsequently GPR-44. Sulprostone, while engaging with prostaglandin E2 receptors and influencing calcium levels, can activate GPR-44 through downstream signaling effects. Alprostadil raises cAMP levels upon binding to its receptors, which may also culminate in the activation of PKA and subsequent activation of GPR-44. Selexipag, although selective for the prostacyclin IP receptor, indirectly increases cAMP levels, again leading to PKA activation and the potential activation of GPR-44. Latanoprost and travoprost, both prostaglandin F2α analogs, primarily activate the prostaglandin F receptor, but the downstream signaling cascade can lead to the synthesis of ligands for GPR-44, increasing its activation. Lastly, carbaprost, yet another prostaglandin F2α analog, activates FP receptors, which could influence the activity of GPR-44 through complex intracellular signaling pathways.