Changes in serum blood-brain barrier markers after bilateral tonic-clonic seizures.

• The serum levels of s-ICAM-1, P-selectin, MMP-9, TIMP-1, and S100B increase rapidly after tonic-clonic seizures in patients with epilepsy. • The pattern of increase in the studied markers may suggest endothelial activation and blood-brain barrier leakage during the first 24 h after seizures. • The levels of MMP-9, TIMP-1, and S100B are increased 72 h after seizures. • Seizures change the serum levels of various endothelial and blood-brain barrier proteins; therefore, the time since the last seizure should always be considered while analysing circulatory biomarkers in patients with epilepsy. Seizures have been shown to increase blood-brain barrier (BBB) permeability, yet the role of this phenomenon is not fully understood. Additionally, dysfunction of the BBB leads to initiation and propagation of seizures in animal models. To demonstrate the increased permeability of the BBB in time, we investigated changes of the serum levels of BBB markers in patients with epilepsy after bilateral tonic-clonic seizures. We chose markers that might reflect endothelial activation (ICAM-1, selectins), BBB leakage (MMP-9, S100B) and mechanisms of BBB restoration (TIMP-1, thrombomodulin -TM). We enrolled 50 consecutive patients hospitalised after bilateral tonic-clonic seizures who agreed to take part in the study and 50 participants with no history of epilepsy. Serum levels of selected markers were measured by ELISA at 1-3, 24, and 72 hours after seizures and one time in the control group. We found increased levels of S100B, ICAM-1, MMP-9 and P-selectin at 1-3 and 24 hours after seizures and TIMP-1 and TM at 24 and 72 hours after seizures as compared to the control group. The level of E-selectin was decreased at 72 hours after seizures. Our findings suggest early activation of endothelium and increased BBB permeability after seizures. While we are aware of the limitations due to the non-specificity of the tested proteins, our results might indicate the presence of prolonged BBB impairment due to seizure activity. [ABSTRACT FROM AUTHOR]