Camilo Rojas1,2, Michal Sala3, Ajit G Thomas1, Amrita Datta Chaudhuri4, Seung-Wan Yoo4, Zhigang Li4, Ranjeet P Dash1, Rana Rais1,4, Norman J Haughey4, Radim Nencka3, Barbara Slusher1,4,5,6,7,8. 1. Johns Hopkins Drug Discovery, Johns Hopkins School of Medicine, Baltimore, Maryland. 2. Department of Molecular and Comparative Pathobiology, Johns Hopkins School of Medicine, Baltimore, Maryland. 3. Chem Research Group, Institute of Organic Chemistry and Biochemistry, Prague, Czech Republic. 4. Department of Neurology, Johns Hopkins School of Medicine, Baltimore, Maryland. 5. Department of Psychiatry and Behavioral Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland. 6. Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, Maryland. 7. Department of Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland. 8. Department of Oncology, Johns Hopkins School of Medicine, Baltimore, Maryland.
Abstract
BACKGROUND AND PURPOSE: Extracellular vesicles (EVs) are constitutively shed from cells and released by various stimuli. Their protein and RNA cargo are modified by the stimulus, and in disease conditions can carry pathological cargo involved in disease progression. Neutral sphingomyelinase 2 (nSMase2) is a major regulator in at least one of several independent routes of EV biogenesis, and its inhibition is a promising new therapeutic approach for neurological disorders. Unfortunately, known inhibitors exhibit μM potency, poor physicochemical properties, and/or limited brain penetration. Here, we sought to identify a drug-like inhibitor of nSMase2. EXPERIMENTAL APPROACH: We conducted a human nSMase2 high throughput screen (>365,000 compounds). Selected hits were optimized focusing on potency, selectivity, metabolic stability, pharmacokinetics, and ability to inhibit EV release in vitro and in vivo. KEY RESULTS: We identified phenyl(R)-(1-(3-(3,4-dimethoxyphenyl)-2,6-dimethylimidazo[1,2-b]pyridazin-8-yl)pyrrolidin-3-yl)-carbamate (PDDC), a potent (pIC50 = 6.57) and selective non-competitive inhibitor of nSMase2. PDDC was metabolically stable, with excellent oral bioavailability (%F = 88) and brain penetration (AUCbrain /AUCplasma = 0.60). PDDC dose-dependently (pEC50 = 5.5) inhibited release of astrocyte-derived extracellular vesicles (ADEV). In an in vivo inflammatory brain injury model, PDDC robustly inhibited ADEV release and the associated peripheral immunological response. A closely related inactive PDDC analogue was ineffective. CONCLUSION AND IMPLICATIONS: PDDC is a structurally novel, potent, orally available, and brain penetrant inhibitor of nSMase2. PDDC inhibited release of ADEVs in tissue culture and in vivo. PDDC is actively being tested in animal models of neurological disease and, along with closely related analogues, is being considered for clinical translation.
BACKGROUND AND PURPOSE: Extracellular vesicles (EVs) are constitutively shed from cells and released by various stimuli. Their protein and RNA cargo are modified by the stimulus, and in disease conditions can carry pathological cargo involved in disease progression. Neutral sphingomyelinase 2 (nSMase2) is a major regulator in at least one of several independent routes of EV biogenesis, and its inhibition is a promising new therapeutic approach for neurological disorders. Unfortunately, known inhibitors exhibit μM potency, poor physicochemical properties, and/or limited brain penetration. Here, we sought to identify a drug-like inhibitor of nSMase2. EXPERIMENTAL APPROACH: We conducted a human nSMase2 high throughput screen (>365,000 compounds). Selected hits were optimized focusing on potency, selectivity, metabolic stability, pharmacokinetics, and ability to inhibit EV release in vitro and in vivo. KEY RESULTS: We identified phenyl(R)-(1-(3-(3,4-dimethoxyphenyl)-2,6-dimethylimidazo[1,2-b]pyridazin-8-yl)pyrrolidin-3-yl)-carbamate (PDDC), a potent (pIC50 = 6.57) and selective non-competitive inhibitor of nSMase2. PDDC was metabolically stable, with excellent oral bioavailability (%F = 88) and brain penetration (AUCbrain /AUCplasma = 0.60). PDDC dose-dependently (pEC50 = 5.5) inhibited release of astrocyte-derived extracellular vesicles (ADEV). In an in vivo inflammatory brain injury model, PDDC robustly inhibited ADEV release and the associated peripheral immunological response. A closely related inactive PDDC analogue was ineffective. CONCLUSION AND IMPLICATIONS: PDDC is a structurally novel, potent, orally available, and brain penetrant inhibitor of nSMase2. PDDC inhibited release of ADEVs in tissue culture and in vivo. PDDC is actively being tested in animal models of neurological disease and, along with closely related analogues, is being considered for clinical translation.
Authors: Michael J Curtis; Steve Alexander; Giuseppe Cirino; James R Docherty; Christopher H George; Mark A Giembycz; Daniel Hoyer; Paul A Insel; Angelo A Izzo; Yong Ji; David J MacEwan; Christopher G Sobey; S Clare Stanford; Mauro M Teixeira; Sue Wonnacott; Amrita Ahluwalia Journal: Br J Pharmacol Date: 2018-04 Impact factor: 8.739
Authors: Chiara Luberto; Daniel F Hassler; Paola Signorelli; Yasuo Okamoto; Hirofumi Sawai; Eric Boros; Debra J Hazen-Martin; Lina M Obeid; Yusuf A Hannun; Gary K Smith Journal: J Biol Chem Date: 2002-08-01 Impact factor: 5.157
Authors: Nicholas S Caron; Raul Banos; Christopher Yanick; Amirah E Aly; Lauren M Byrne; Ethan D Smith; Yuanyun Xie; Stephen E P Smith; Nalini Potluri; Hailey Findlay Black; Lorenzo Casal; Seunghyun Ko; Daphne Cheung; Hyeongju Kim; Ihn Sik Seong; Edward J Wild; Ji-Joon Song; Michael R Hayden; Amber L Southwell Journal: J Neurosci Date: 2020-12-11 Impact factor: 6.167
Authors: Nienke M de Wit; Kevin Mol; Sabela Rodríguez-Lorenzo; Helga E de Vries; Gijs Kooij Journal: Front Immunol Date: 2021-01-29 Impact factor: 7.561
Authors: Carolyn Tallon; Kristen R Hollinger; Arindom Pal; Benjamin J Bell; Rana Rais; Takashi Tsukamoto; Kenneth W Witwer; Norman J Haughey; Barbara S Slusher Journal: Drug Discov Today Date: 2021-03-31 Impact factor: 8.369