N8279 (NCATS-SM8864) is a selective, brain-penetrant small molecule Gαq-biased GHSR1a agonist with binding IC50 of 1.3 uM.N8279 is nearly an order of magnitude (8.9-fold) more potent than the endogenous ligand ghrelin and is a full agonist.iCa2+ EC50 of N8279 is 41-fold more potent than its GHSR1a binding IC50, suggesting possible allosteric activity, which could be competitively inhibited by GHSR1a antagonists YIL781 and JMV2959.N8279 is a weak activator of GHSR1a-mediated, βarr2-dependent cellular responses relative to ghrelin.N8279 requires receptor sites and/or conformational states driven by the GHSR1a ECD that are distinct from ghrelin.N8279 is brain-penetrant and attenuates aberrant DAergic behavior in mice.
KARI-201 is a multifunctional small molecule that demonstrates dual activity as a highly selective inhibitor of acid sphingomyelinase (ASM) and an agonist of the ghrelin receptor. It operates as a competitive inhibitor by binding directly to the active site of ASM. Studies reveal that the incorporation of KARI-201 into ASM decreases in a concentration-dependent manner with sphingomyelin, resulting in KM values of 332.5, 433.9, and 572.6 μM at KARI-201 concentrations of 1, 10, and 100 μM, respectively. In preclinical models, KARI-201 has shown efficacy in reducing amyloid pathology and reversing cognitive deficits in APP/PS1 mice. Additionally, it enhances autophagy degradation by promoting lysosomal biogenesis in neuronal cells. As a ghrelin receptor agonist, KARI-201 also supports hippocampal neurogenesis and improves synaptic plasticity, making it a promising therapeutic candidate for neurodegenerative conditions.
Capromorelin Tartrate (CP 424391-18), a member of the growth hormone secretagogue (GHS) class of drugs, is a ghrelin receptor agonist and a novel therapy for stimulation of appetite in dogs with Ki of 7 nM for hGHS-R1a and EC50 of 3 nM for rat pituicyte.
Ghrelin agonist HM01 is a novel potent, orally available ghrelin (GHS-R) agonist with Ki of 1.42 nM (human GHS-R1a), induces potent activation of intracellular calcium signaling with EC50 of 1.25 nM.
Macimorelin (EP-1572) acetate, a GH secretagogue, is an orally active GHSR agonist. Macimorelin acetate stimulates GH release. Macimorelin acetate can be used in the research of adult growth hormone deficiency (AGHD), and Cancer anorexia-cachexia syndrome (CACS).
GSK1614343 is the potent antagonist of growth hormone secretagogues type 1a (GHS1a) receptors. GSK1614343 inhibits the calcium response induced by ghrelin with a pIC50 value of 7.90. GSK1614343 represents a useful tool to investigate the physiological relevance of the ghrelin system in rat models.