RT Journal Article
SR Electronic
T1 AβPP/APLP2 Family of Kunitz Serine Proteinase Inhibitors Regulate Cerebral Thrombosis
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 5666
OP 5670
DO 10.1523/JNEUROSCI.0095-09.2009
VO 29
IS 17
A1 Feng Xu
A1 Mary Lou Previti
A1 Marvin T. Nieman
A1 Judianne Davis
A1 Alvin H. Schmaier
A1 William E. Van Nostrand
YR 2009
UL http://www.jneurosci.org/content/29/17/5666.abstract
AB The amyloid β-protein precursor (AβPP) is best recognized as the precursor to the Aβ peptide that accumulates in the brains of patients with Alzheimer's disease, but less is known about its physiological functions. Isoforms of AβPP that contain a Kunitz-type serine proteinase inhibitor (KPI) domain are expressed in brain and, outside the CNS, in circulating blood platelets. Recently, we showed that KPI-containing forms of AβPP regulates cerebral thrombosis in vivo (Xu et al., 2005, 2007). Amyloid precursor like protein-2 (APLP2), a closely related homolog to AβPP, also possesses a highly conserved KPI domain. Virtually nothing is known of its function. Here, we show that APLP2 also regulates cerebral thrombosis risk. Recombinant purified KPI domains of AβPP and APLP2 both inhibit the plasma clotting in vitro. In a carotid artery thrombosis model, both AβPP−/− and APLP2−/− mice exhibit similar significantly shorter times to vessel occlusion compared with wild-type mice indicating a prothrombotic phenotype. Similarly, in an experimental model of intracerebral hemorrhage, both AβPP−/− and APLP2−/− mice produce significantly smaller hematomas with reduced brain hemoglobin content compared with wild-type mice. Together, these results indicate that AβPP and APLP2 share overlapping anticoagulant functions with regard to regulating thrombosis after cerebral vascular injury.