N-Phosphonomethyl Dipeptides and Their Phosphonate Prodrugs, a New Generation of Neutral Endopeptidase (NEP, EC 3.4.24.11) Inhibitors

Abstract

Inhibitors of the zinc protease neutral endopeptidase (NEP, EC 3.4.24.11) offer significant therapeutic interest as antihypertensives due to their ability to potentiate the biological action of the circulating natriuretic hormone ANF (atrial natriuretic factor). N-Phosphonomethyl dipeptides bearing a central (4-phenyl)phenylalanine residue have been designed to exert potent and selective NEP inhibition. In particular, (S)-3-[N-[2- [(phosphonomethyl)amino]-3-(4-biphenylyl)propionyl]amino]propionic acid (10a) (CGS 24592) displayed high inhibitory potency in vitro (IC50 = 1.9 +/- 0.1 nM) and a long plasma half-life in rats but lacked oral bioavailability. This drawback was overcome by using esterase-sensitive (acyloxy)alkyl phosphonates. More remarkable, several diaryl phosphonate derivatives of 10a also performed as effective prodrugs. Specifically, the structurally simple diphenyl phosphonate 18 (CGS 25462) induced potent inhibition of NEP ex vivo for at least 8 h after oral administration to rats (30 mg/kg). Its antihypertensive effect was demonstrated in DOCA-salt rats. At 30 mg/kg orally, 18 caused a significant reduction in mean arterial pressure measuring -35 +/- 7 mmHg at 5-h postdosing. The alpha-aminomethyl phosphonate 18 represents a new generation of selective NEP inhibitors that combine high potency, long duration of action, and oral bioavailability. Therefore, it holds promise as a novel therapeutic agent for the treatment of human hypertension and congestive heart failure.

Targeting thyroid hormone receptor-β agonists to the liver reduces cholesterol and triglycerides and improves the therapeutic index

“…Differences in binding affinity (24) and enzyme kinetics (25) likely reflect geometrical differences in structure and the inability of many binding sites to accommodate both a planar mononegatively charged carboxylate and a tetrahedral dinegatively charged phosphonate. In vivo, phosphonates exhibit a lower volume of distribution (26), presumably because of decreased cellular penetration arising from their greater negative charge or reduced recognition by the cellular transporters used to transport carboxylates.…”

“…MB07811, MB07344, KB-141 (16), and the glutathione conjugate 2 (26) were synthesized at Metabasis Therapeutics (La Jolla, CA).…”

Neuropeptide-stimulated cell migration in prostate cancer cells is mediated by RhoA kinase signaling and inhibited by neutral endopeptidase

“…In contrast, the lipid agonist lysophosphatidic acid (LPA)-induced RhoA activation and was not affected by NEP expression (Figure 4a). Next we used the specific NEP protease inhibitor CGS24592 (De Lombaert et al, 1994) CGS24592 alone had no effect on RhoA activation in LNCaP cells (data not shown). Together, these results demonstrate that the catalytic activity of NEP inhibits bombesin-and ET-1-stimulated RhoA activation in PC cells.…”

Neutral endopeptidase inhibits prostate cancer cell migration by blocking focal adhesion kinase signaling

“…PC cell lines were maintained in RPMI 1640 media supplemented with 2 mM glutamine, 1% nonessential amino acids, 100 U/ml streptomycin and penicillin, and 10% FCS. Reagents used include recombinant NEP (rNEP; Arris Pharmaceuticals Corp., South San Francisco, California, USA); CGS24592 (Novartis Pharmaceuticals, Summit, New Jersey, USA) (12); and PP2 (Calbiochem-Novabiochem Ltd., La Jolla, California, USA). The following antibodies were used: mouse monoclonals to NEP (J5; Beckman Coulter, Fullerton, California, USA); to Lyn (H-6), to cSrc (B-12), to anti-pTyr (PY20; Santa Cruz Biotechnology Inc., Santa Cruz, California, USA); rabbit polyclonals to NEP (5B5; Arris Pharmaceuticals Corp.), to p85 (Upstate Biotechnology, Lake Placid, New York, USA), to FAK (C-20), to Lyn (clone 44), and to cSrc (SRC-2; Santa Cruz Biotechnology Inc.).…”