Abstract W P229: Reduction of Peroxiredoxin 5 Concentration in Patients following Ischemic Stroke

Abstract

Background: There is a marked inflammatory response within the brain after stroke. Peroxiredoxins (PRXs) are endogenous anti-oxidant proteins, but recent data suggest that PRXs may be responsible for initiating inflammation in the brain following cerebral ischemia. In this study we evaluated the relationship between PRX5 and biomarkers of inflammation following ischemic stroke. Methods: In a prospective study of patients with ischemic stroke, PRX5 concentrations were determined by standard ELISA in plasma samples (N=98) obtained at 3 days after stroke onset. Relationships between stroke severity, biomarkers of inflammation and stroke outcome were explored. Results: At 3 days after stroke, PRX5 concentrations were significantly lower in patients with severe stroke (NIHSS ≥17; 37.6 ng/mL [28.5, 45.3]) as compared to patients with moderate stroke (NIHSS 6-16; 48.0 ng/mL [36.5, 88.6]) or mild stroke (NIHSS ≤5; [40.5, 76.3]); P =0.001. PRX5 was inversely correlated with the number of white blood cells, neutrophils, and monocytes as well as with plasma CRP, TNF-α, IL-6, IL-10 and IL-2. None of these correlations remained significant after controlling for stroke severity. Patients with higher plasma PRX5 at 3 days were more likely to have good outcome (mRS≤2) at 3 months ( P =0.019), but this relationship was lost after controlling for stroke severity. Discussion: Plasma concentrations of PRX5 are decreased in patients with severe stroke and inversely correlated with biomarkers of inflammation. These data suggest that the initiator of systemic inflammation after stroke is not PRX5. Further, they show that severe brain injury leads to a loss of circulating anti-oxidant proteins.