Activated protein C prevents neuronal apoptosis via protease activated receptors 1 and 3.
Activated protein C (APC), a serine protease with anticoagulant and anti-inflammatory activities, exerts direct cytoprotective effects on endothelium via endothelial protein C receptor-dependent activation of protease activated receptor 1 (PAR1). Here, we report that APC protects mouse cortical neurons from two divergent inducers of apoptosis, N-methyl-D-aspartate (NMDA) and staurosporine. APC blocked several steps in NMDA-induced apoptosis downstream to nitric oxide, i.e., caspase-3 activation, nuclear translocation of apoptosis-inducing factor (AIF), and induction of p53, and prevented staurosporine-induced apoptosis by blocking caspase-8 activation upstream of caspase-3 activation and AIF nuclear translocation. Intracerebral APC infusion dose dependently reduced NMDA excitotoxicity in mice. By using different anti-PARs antibodies and mice with single PAR1, PAR3, or PAR4 deletion, we demonstrated that direct neuronal protective effects of APC in vitro and in vivo require PAR1 and PAR3. Thus, PAR1 and PAR3 mediate anti-apoptotic signaling by APC in neurons, which may suggest novel treatments for neurodegenerative disorders.
Guo
Huang
H
Socratech Laboratories, Rochester, NY 14620, USA.
Liu
Dong
D
Gelbard
Harris
H
Cheng
Tong
T
Insalaco
Rae
R
Fernández
José A
JA
Griffin
John H
JH
Zlokovic
Berislav V
BV
D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D051033:Apoptosis Inducing Factor; D020169:Caspases / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D005333:Fetus; D005420:Flavoproteins / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016202:N-Methylaspartate / Q000494:pharmacology; D019636:Neurodegenerative Diseases / Q000201:enzymology; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D011486:Protein C / Q000378:metabolism* / Q000494:pharmacology; D044463:Receptor, PAR-1 / Q000235:genetics / Q000378:metabolism*; D018179:Receptors, Thrombin / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D019311:Staurosporine / Q000494:pharmacology; D016159:Tumor Suppressor Protein p53 / Q000187:drug effects / Q000378:metabolism; D010975:Platelet Aggregation Inhibitors
D051033:Apoptosis Inducing Factor; D005420:Flavoproteins; D008565:Membrane Proteins; C494830:AIFM1 protein, mouse; D011486:Protein C; D044463:Receptor, PAR-1; D018179:Receptors, Thrombin; D016159:Tumor Suppressor Protein p53; C105295:protease-activated receptor 3; D016202:N-Methylaspartate; D020169:Caspases; D019311:Staurosporine; D010975:Platelet Aggregation Inhibitors