Relationship between elevated cerebrospinal fluid levels of plasminogen activator inhibitor 1 and neuronal destruction in patients with neuropsychiatric systemic lupus erythematosus.
OBJECTIVE
A homeostatic imbalance between coagulation and fibrinolysis might occur intrathecally in neuropsychiatric systemic lupus erythematosus (NPSLE). However, there are no published data on levels of fibrinolytic factors in the cerebrospinal fluid (CSF) of patients with NPSLE. The present study was undertaken to assess CSF levels of fibrinolytic molecules, including urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA), D-dimer, and plasminogen activator inhibitor 1 (PAI-1), in SLE patients with clinically verified neuropsychiatric involvement and to compare these levels with those in SLE patients without neuropsychiatric involvement and in healthy subjects.


METHODS
Levels of uPA, tPA, and PAI-1 were assessed in CSF from 94 patients with SLE (33 who had NPSLE, 56 who did not have NPSLE, and 5 who were positive for antiphospholipid antibody [not included in the NPSLE or non-NPSLE group]) and from 53 age-matched controls. Patients were evaluated clinically, with magnetic resonance imaging of the brain, analyses of neuronal/glial degradation products in CSF, and neuropsychiatric testing.


RESULTS
In the group of patients with NPSLE, intrathecal PAI-1 levels were significantly elevated compared with levels in SLE patients without overt neuropsychiatric involvement (P < 0.05) and in healthy controls (P < 0.001). In contrast, intrathecal levels of uPA did not differ significantly. Intrathecal levels of PAI-1 correlated significantly with CSF levels of interleukin-6 (IL-6) (r = 0.34, P < 0.001) and IL-8 (r = 0.33, P < 0.001). Importantly, increased PAI-1 and D-dimer levels were observed in SLE patients who had pathologically elevated levels of glial fibrillary acidic protein, neurofilament triplet protein, and tau protein in CSF.


CONCLUSIONS
Intrathecal release of PAI-1 is increased in patients with NPSLE. This results in impaired fibrinolysis, which might contribute to neuronal and astrocytic damage in NPSLE.
Kwieciński
Jakub
J
Göteborg University, Göteborg, Sweden.
Kłak
Marcin
M
Trysberg
Estelle
E
Blennow
Kaj
K
Tarkowski
Andrej
A
Jin
Tao
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000134:cerebrospinal fluid; D006801:Humans; D020945:Lupus Vasculitis, Central Nervous System / Q000134:cerebrospinal fluid* / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009410:Nerve Degeneration / Q000473:pathology*; D009474:Neurons / Q000473:pathology*; D017395:Plasminogen Activator Inhibitor 1 / Q000134:cerebrospinal fluid*; D019396:Tissue Polypeptide Antigen / Q000134:cerebrospinal fluid; D014568:Urokinase-Type Plasminogen Activator / Q000134:cerebrospinal fluid; D055815:Young Adult
D005338:Fibrin Fibrinogen Degradation Products; D017395:Plasminogen Activator Inhibitor 1; D019396:Tissue Polypeptide Antigen; C036309:fibrin fragment D; D014568:Urokinase-Type Plasminogen Activator