A novel class of prolyl hydroxylase inhibitors induces angiogenesis and exerts organ protection against ischemia.
OBJECTIVE
Hypoxia inducible factor (HIF) plays a pivotal role in the adaptation to ischemic conditions. Its activity is modulated by an oxygen-dependent hydroxylation of proline residues by prolyl hydroxylases (PHD).


RESULTS
We discovered 2 unique compounds (TM6008 and TM6089), which inhibited PHD and stabilized HIF activity in vitro. Our docking simulation studies based on the 3-dimensional structure of human PHD2 disclosed that they preferentially bind to the active site of PHD. Whereas PHD inhibitors previously reported inhibit PHD activity via iron chelation, TM6089 does not share an iron chelating motif and is devoid of iron chelating activity. In vitro Matrigel assays and in vivo sponge assays demonstrated enhancement of angiogenesis by local administration of TM6008 and TM6089. Their oral administration stimulated HIF activity in various organs of transgenic rats expressing a hypoxia-responsive reporter vector. No acute toxicity was observed up to 2 weeks after a single oral dose of 2000 mg/kg for TM6008. Oral administration of TM6008 protected neurons in a model of cerebrovascular disease. The protection was associated with amelioration of apoptosis but independent of enhanced angiogenesis.


CONCLUSIONS
The present study uncovered beneficial effects of novel PHD inhibitors preferentially binding to the active site of PHD.
Nangaku
Masaomi
M
Institute of Medical Sciences and Division of Nephrology, Hypertension and Metabolism, Tokai University School of Medicine, Isehara, Kanagawa 259-1193, Japan.
Izuhara
Yuko
Y
Takizawa
Shunya
S
Yamashita
Toshiharu
T
Fujii-Kuriyama
Yoshiaki
Y
Ohneda
Osamu
O
Yamamoto
Masayuki
M
van Ypersele de Strihou
Charles
C
Hirayama
Noriaki
N
Miyata
Toshio
T
D000284:Administration, Oral; D043925:Angiogenesis Inducing Agents / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000633:toxicity; D000818:Animals; D030801:Animals, Genetically Modified; D017209:Apoptosis / Q000187:drug effects; D001665:Binding Sites; D002545:Brain Ischemia / Q000473:pathology / Q000517:prevention & control*; D002478:Cells, Cultured; D002614:Chelating Agents / Q000494:pharmacology; D003198:Computer Simulation; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D015195:Drug Design; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000633:toxicity; D017930:Genes, Reporter; D005849:Gerbillinae; D006321:Heart / Q000187:drug effects; D006801:Humans; D006900:Hydroxylation; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism*; D064799:Hypoxia-Inducible Factor-Proline Dioxygenases; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D007928:Lethal Dose 50; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008958:Models, Molecular; D015394:Molecular Structure; D009206:Myocardium / Q000378:metabolism; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D009474:Neurons / Q000187:drug effects / Q000473:pathology; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000633:toxicity; D011393:Procollagen-Proline Dioxygenase / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D051381:Rats
D043925:Angiogenesis Inducing Agents; D002614:Chelating Agents; D004791:Enzyme Inhibitors; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D018696:Neuroprotective Agents; C490190:EGLN1 protein, human; D011393:Procollagen-Proline Dioxygenase; D064799:Hypoxia-Inducible Factor-Proline Dioxygenases