H3R antagonist 1 hydrochloride is a histamine receptor 3 (H3R) inverse agonist extracted from patent WO2013107336A1, compound example 2.

Treatment with H3R antagonist 1 hydrochloride, which is a H3R inverse agonist, promotes oligodendrocyte precursor cell (OPC) differentiation in a dose-dependent manner, at EC50=25 nM. Western blot reveals a significant increase in expression levels of two markers of mature oligodendrocytes, myelin-associated glycoprotein (MAG) and myeline basic protein (MBP) in differentiating oligodendrocytes after treatment with H3R antagonist 1 hydrochloride, which suggests that treatment with H3R antagonist 1 hydrochloride drives more OPCs to differentiate. H3R antagonist 1 hydrochloride increases the Forskolin-stimulated cAMP level in the primary oligodendrocyte precursor cells in a dose-dependent manner[1].

The ability of H3R antagonist 1 hydrochloride-1 to enhance in vivo remyelination is determined with the Cuprizone/Rapamycin-induced demyelination model. Mice are treated with Cuprizone diet combined with intraperitoneal injections of Rapamycin for 5 weeks followed by 9 days of compound administration. Cuprizone diet plus intraperitoneal injections of Rapamycin induced severe demyelination in both corpus callosum and cortex and treatment with H3R antagonist 1 hydrochloride (30 mg/kg, 9 days) significantly increases density of myelin specific Black-gold II staining in the lesion of corpus callosum and cortex in forebrain, compared to vehicle control group[1].

[1]. WANG, Rong, et al. THERAPEUTIC USES. WO2013107336A1.