Influence of Interleukin-1 Gene Cluster Polymorphisms on the Susceptibility and Outcomes of Acute Stroke in Egyptian Patients

Abstract

Interleukin-1 (IL-1) has pleiotropic actions in the central nervous system. A growing corpus of evidence has indicated an important role of this cytokine in the development of brain damage following cerebral ischemia. The objective of this study is to investigate the influence of IL-1 cluster gene polymorphisms on the susceptibility of acute stroke and its outcomes in Egyptian patient. 320 patients with new or recurrent stroke [176 with atherothrombotic cerebral infarction, 79 with intracerebral hemorrhage (ICH), and 65 with subarachnoid hemorrhage (SAH)] and 320 controls were included in the study. IL-1b -511, IL-1a -889, and IL-1RN VNTR polymorphisms were analyzed using polymerase chain reaction-restriction fragment length polymorphism. Serum level of IL-1 was measured by enzyme linked immunosorbent assay. All patients were followed for neurological and functional impairments 7 days, 1, 3 and 6 months after the onset of the stroke. We found that IL-1b -511 gene polymorphisms were significantly increased in patients with atherothrombotic, intracerebral, and SAH. Subjects with IL-1a -889 CT and TT genotypes were significantly more likely to have atherothrombotic infarction. Both IL-1b -511, IL-1a -889 genes polymorphisms were significantly more likely to have severe neurological and functional impairment, while IL-1RN 2/2 genotype was significantly decreased in atherothrombotic infarction and ICH groups and showed less severe neurological and functional impairments 7 days, 1, 3, and 6 months after the onset of the stroke compared with carriers of the IL1RN 1/1 and 1/2 genotypes. We concluded that IL-1 cluster gene polymorphisms were associated with risk of acute stroke. IL-1b, IL-1a gene polymorphisms were associated with more severe functional and neurological impairments, while IL-1RN VNTR polymorphisms were associated with good outcomes.