Toward New AQP4 Inhibitors: ORI-TRN-002.

Area of Science:

• Biochemistry
• Neuroscience
• Pharmacology

Background:

• Cerebral edema is a dangerous condition requiring new treatments that prevent fluid buildup, not just reduce pressure.
• Aquaporin 4 (AQP4) water channels are implicated in cerebral edema, making them a therapeutic target.
• Developing selective and effective AQP4 inhibitors faces challenges in delivery, toxicity, and sustained action.

Purpose of the Study:

• To discover novel Aquaporin 4 (AQP4) inhibitors for potential cerebral edema treatment.
• To identify compounds with improved properties like solubility and reduced protein binding compared to existing inhibitors.
• To explore new therapeutic strategies targeting the formation of cerebral edema.

Main Methods:

• Density-functional theory (DFT) calculations identified a new stable tautomer of TGN-020.
• COSMOsim-3D virtual screening of proprietary compounds based on the novel tautomer template.
• In vitro evaluation of candidate ORI-TRN-002 using AQP4-expressing Xenopus laevis oocytes and a high-resolution volume recording system.

Main Results:

• A novel, thermodynamically stable tautomer of TGN-020 was identified.
• Virtual screening identified ORI-TRN-002, an electronic homologue of TGN-020, with high solubility and low protein binding.
• ORI-TRN-002 demonstrated significant Aquaporin 4 (AQP4) inhibition with an IC50 of 2.9 ± 0.6 µM.

Conclusions:

• ORI-TRN-002 is a novel and potent Aquaporin 4 (AQP4) inhibitor.
• ORI-TRN-002 possesses superior solubility and pharmacokinetic properties compared to other AQP4 inhibitors.
• The findings suggest ORI-TRN-002 holds potential as a future prophylactic therapy for cerebral edema.