Animal experiment:

Rats[3]In a related experiment to evaluate the role of central ACE2 in stroke, randomly assigned rats (n = 16) are treated centrally for five days prior to and three days after stroke with the ACE2 inhibitor MLN-4760 (100 μM infused at a rate of 0.5 μL/h) or sterile saline (0.9%) via intracerebroventricular infusion. Following endothelin-1 MCAO, neurological function is assessed at 4 h, 1 d, and 3 d, and brains are harvested at 3 d post-stroke for infarct volume analysis as above[3].

MLN-4760 is a potent and selective human ACE2 inhibitor (IC50, 0.44 nM), with excellent selectivity (>5000-fold) versus related enzymes including human testicular ACE (IC50, >100 μM) and bovine carboxypeptidase A (CPDA; IC50, 27 μM).

MLN-4760 is a potent and selective human ACE2 inhibitor (IC50, 0.44 nM), with excellent selectivity (>5000-fold) versus related enzymes human testicular ACE (IC50, >100 μM) and bovine carboxypeptidase A (CPDA; IC50, 27 μM)[1]. MLN-4760 effectively quenches cleavage of the 7-Mca-YVADAPK(Dnp) in rhACE2. MLN-4760 shows pIC50 at rhACE2 of 8.5±0.1 and at rhACE of 4.4±0.2. MLN-4760 also shows pIC50 at rhACE2 of 4.7±0.1, 6.9±0.1 and at ACE of 4.4±0.1, 6.2±0.1 in murine heart and mononuclear cells (MNCs), resepctively[2].

MLN-4760 (100 μM, intracerebroventricular infusion for five days) significantly worsens neurological function at 4 h and 3 d post-stroke without significantly increasing infarct volume[3].

[1]. Dales NA, et al. Substrate-based design of the first class of angiotensin-converting enzyme-related carboxypeptidase (ACE2) inhibitors. J Am Chem Soc. 2002 Oct 9;124(40):11852-3. [2]. Joshi S, et al. Angiotensin converting enzyme versus angiotensin converting enzyme-2 selectivity of MLN-4760 and DX600 in human and murine bone marrow-derived cells. Eur J Pharmacol. 2016 Mar 5;774:25-33. [3]. Bennion DM, et al. Activation of the Neuroprotective Angiotensin-Converting Enzyme 2 in Rat Ischemic Stroke. Hypertension. 2015 Jul;66(1):141-8.