Small Molecule Copper and Its Relative Metabolites in Serum of Cerebral Ischemic Stroke Patients

BackgroundCopper is a strong pro-oxidant. The most important pro-oxidative form in serum is small molecule copper (SMC), which is copper that is loosely bound to small molecules, such as amino acids and polypeptides. The association between copper and atherosclerotic diseases has been confirmed, but that between SMC and cerebral ischemic stroke (CIS), one of the most principal manifestations and causes of death of atherosclerotic disease, is not yet clear.MethodsWe recruited 45 CIS patients and 25 age- and gender-matched healthy controls. We detected their serum levels of SMC, total copper, homocysteine (Hcy), and ceruloplasmin (CP), as well as urinary total copper, and analyzed the relationship of SMC with these aforementioned metabolites or compounds in CIS patients.ResultsSMC was 4.2 ± .5 µg/L and 2.1 ± .9 µg/L; total copper in sera was 1345.5 ± 308.2 µg/L and 1180.3 ± 134.0 µg/L; and total copper in urine was 27.6 ± 9.3 µg/L and 18.8 ± 8.1 µg/L in patients and controls, respectively (all P < .05). Serum CP activity in CIS patients was 59.92 ± 12.11 U/L versus 37.76 ± 5.71 U/L in controls (P = .0001). The concentration of SMC was positively correlated with CP activity, Hcy concentration in sera, and urinary total copper.ConclusionThe serum level of SMC and total copper is remarkably elevated, and SMC positively correlates with Hcy, CP activity, and urinary total copper in CIS patients.