Abstract W P386: Matrix Metalloproteinase Levels May Mediate Ischemic Stroke Incidence and Recovery in Stroke Patients with Metabolic Syndrome

Abstract

Intro: The metabolic syndrome (MetS) is highly prevalent in the US characterized by a combination of risk factors that can lead to cardiovascular disease (CVD). While the association between CVD, inflammation, and stroke risk has been characterized, the immune mechanisms underlying increased risk of stroke in MetS is unclear. While stroke risk is higher among MetS, MetS individuals tend to have better stroke recovery than controls. The immune response may mediate these paradoxical observations in stroke. In particular, matrix metalloproteinases (MMP) enzymes play a role in stroke incidence and recovery. Similar to MetS, MMPs have a dual role in stroke, as they are harmful immediately after stroke, but play a vital role in brain repair and recovery following stroke. We hypothesize that elevated levels of MMPs in MetS may account for the paradoxical increased stroke risk, yet better recovery seen in stroke patients with MetS. Methods: MMP protein concentrations were obtained from fasting venous samples and quantified using a Multi-Analyte Profiling Kit (Millipore) on the Luminex®. Each subject was assigned a metabolic risk score (MRS) based on sex, age, SBP, treatment for hypertension, smoking and diabetes status, HDL, and total cholesterol. B-mode ultrasound images of the right common carotid artery were obtained to measure intima-medial thickness (cIMT). Spearman correlations were used to measure the relationship between MRS, cIMT, and MMP levels. Results: In n=68 subjects (60% female) with a mean age of 48+14 yrs, MRS of 25+12, and cIMT of 0.57+0.12 mm. MRS was significantly correlated with cIMT (r=0.39, p< .001). Further, cIMT was positively correlated with MMP1 (r=0.025, p=0.04), MMP7 (r=0.5, p=0.01), and MMP9 (r=0.31, p=0.01). Conclusion: Plasma concentrations of MMP1, 7, and 9 were significantly correlated with cIMT, indicating that increased severity of MetS is associated with increased inflammation. Elevated MMP protein levels may account for the increased stroke risk, yet better recovery seen in stroke patients with MetS.