Procarboxypeptidase U (proCPU, TAFI, proCPB2) in cerebrospinal fluid during ischemic stroke is associated with stroke progression, outcome and blood-brain barrier dysfunction

Background Procarboxypeptidase U (proCPU, TAFI, proCPB2), the zymogen of CPU which is a potent antifibrinolytic enzyme and a modulator of inflammation has previously been investigated in plasma of stroke patients, but so far, no information on the proCPU levels in cerebrospinal fluid (CSF) during acute ischemic stroke (AIS) is available. Objectives This case-control observational study investigates proCPU in CSF of AIS patients compared with controls with an intact blood-brain barrier (BBB) and evaluates the relationship of CSF/plasma proCPU ratios with stroke parameters. Methods A sensitive HPLC-based enzymatic assay was used to determine proCPU levels in CSF of non-thrombolyzed patients in the hyperacute phase (<24h after onset) of AIS (n=72). Individuals (n=32) without stroke, an intact BBB and no apparent abnormalities in biochemical and microbiological tests, served as controls. Relations between the CSF/plasma proCPU ratio and (a) stroke severity, (b) stroke progression/recurrence, (c) stroke outcome and (d) BBB dysfunction (CSF/serum albumin ratio) were assessed. Results Mean (SEM) proCPU levels were elevated in the CSF of stroke patients compared with controls (4.36 (0.23) U/L vs. 3.50 (0.23) U/L). Higher median [IQR] CSF/plasma proCPU ratios were found in patients with stroke progression ((6.0 [4.2-6.9])x10-3) and poor outcome ((6.4 [3.9-7.0])x10-3) after 3 months (mRS>3) compared with patients with no progression ((3.9 [2.7-5.4])x10-3) or better outcome ((4.0 [2.8-5.0])x10-3). In stroke patients with a disrupted BBB, proCPU ratios were higher compared with stroke patients with an intact BBB (6.4 [5.8-9.0])x10-3 vs. (3.7 [2.8-5.0])x10-3). Conclusions ProCPU is increased in CSF during hyperacute ischemic stroke and are associated with stroke progression and outcome after 3 months, most likely due to BBB dysfunction in the hyperacute phase of ischemic stroke.

Publication year:2018

Keywords:A1 Journal article

BOF-keylabel:yes

BOF-publication weight:3

CSS-citation score:1

Authors from:Higher Education

Accessibility:Open