Background: High-mobility group box 1 protein (HMGB1) is a nuclear factor that is a potent proinflammatory mediator, and may trigger increases in other inflammatory cytokines. The inflammatory cytokines in the cerebrospinal fluid (CSF) of patients with subarachnoid hemorrhage (SAH) have been reported previously, but HMGB1 has not. In this study, we measured HMGB1 and the inflammatory cytokines in the CSF of patients with SAH.
Methods: CSF samples were collected on days 3, 7, and 14 from the drainage tubes of the postaneurysm clips of 39 patients with SAH. HMGB1, interleukin-6 (IL-6), IL-8, and tumor necrosis factor alpha (TNF-alpha) were measured in the CSF, and compared between the patients with favorable (good recovery and moderate disability) and unfavorable outcomes (severe disability, vegetative state, and death) at 3 months.
Results: In the unfavorable outcome group, HMGB1 (P = 0.017), IL-6 (P = 0.003), IL-8 (P = 0.041), and TNF-alpha (P = 0.002) were significantly increased. HMGB1 correlated significantly with IL-6, IL-8, and TNF-alpha (R = 0.672, 0.421, and 0.697, respectively).
Conclusions: HMGB1 was increased in the CSF of SAH patients with an unfavorable outcome, as were the other cytokines. These results suggest that HMGB1 and cytokines are related to the brain damage observed after SAH. HMGB1 might play a key role in the inflammatory response in the CNS of SAH patients.