Expression of inflammatory markers and NMDA receptors in the peripheral blood of stroke patients

Background
Identifying early molecular markers in ischemic stroke could help in reducing acute adverse effects of brain tissue after recanalization of clogged blood vessels.

Objectives
In this study, we evaluated the gene expression levels of glutamate N-methyl-D-aspartate receptor (NMDAR) subunits (NR2A and NR3A) and inflammatory markers, as well as some oxidative stress markers in the peripheral blood of ischemic patients 24 h and 72 h after admission to the hospital.

Material and methods
38 patients with ischemic stroke and 29 non-stroke individuals were included in the study. Prognosis and long-term outcomes of patients were evaluated using infarct area measurement from computed tomography scans and the Scandinavian neurological stroke scale. To identify serum biomarker changes, malondialdehyde (MDA) and NO (nitric oxide) levels were measured. A quantitative real-time PCR protocol was performed in order to evaluate the gene expression changes of NR2A, NR3A, TNF-α and interleukin-6 in selectively-isolated peripheral lymphocyte.

Results
Ischemic stroke induced a massive loss of lymphocytes (as determined by total lymphocyte RNA levels). The mRNA levels of NR2A and NR3A were also significantly decreased 24 h and 72 h after admission to the hospital. We also observed a down-regulation of TNF-α and IL-6 gene expression during the first day after admission. The serum level of NO showed a reduction from day one to day three, while MDA increased on day one of admission.

Conclusions
Changes in inflammatory cytokines following an ischemic attack could stimulate glutamate receptors in peripheral lymphocytes. As preliminary findings, this phenomenon could be considered as a prognostic and therapeutic tool in ischemic stroke management.