Hcyb1 is a highly selective, orally active PDE2 inhibitor. Hcyb1 has a highly selective inhibition of PDE2A (IC50=0.57 μM) and over 250-fold selectivity against other recombinant PDE family members. Hcyb1 produces neuroprotective and antidepressant‐like effects most likely mediated by cAMP/cGMP-CREB-BDNF signaling[1].

Hcyb1 (1~100 nM; 10 minutes) increases cGMP levels by 1.7~2.3 folds[1].Hcyb1 (1 nM; 24 hours) increases both cGMP and cAMP levels[1].Hcyb1 (24 hours) treatment also increases the levels of phosphorylation of CREB and BDNF in HT-22 cells[1].Hcyb1 promotes HT-22 cell viability and increase the cGMP and cAMP accumulation in HT-22 cells[1].Hcyb1 exhibits the concentration- and time-dependent effects on cell viability in HT-22 cells[2].

Hcyb1 (0.5, 1, and 2 mg/kg, i.g.) decreases the immobility time in both forced swimming and tail suspension tests, without altering locomotor activity[3].

[1]. Li Liu, et al. The neuroprotective and antidepressant-like effects of Hcyb1, a novel selective PDE2 inhibitor. CNS Neurosci Ther. 2018 Jul;24(7):652-660.
[2]. Meng-Jia Zhu, et al. Phosphodiesterase 2 inhibitor Hcyb1 reverses corticosterone-induced neurotoxicity and depression-like behavior. Psychopharmacology (Berl). 2020 Nov;237(11):3215-3224.