High-mobility group box 1 (
HMGB1) was shown to be an important extracellular mediator involved in vascular
inflammation of animals following
subarachnoid hemorrhage (SAH). This study is of interest to examine the efficacy of
purpurogallin, a natural
phenol, on the alternation of
cytokines and
HMGB1 in a SAH model. A rodent double
hemorrhage SAH model was employed. Basilar arteries (BAs) were harvested to examine
HMGB1 mRNA and
protein expression (Western blot). CSF samples were to examine IL-1β,
IL-6,
IL-8, and TNF-α (rt-PCR). Deformed endothelial wall, tortuous elastic lamina, and necrotic smooth muscle were observed in the vessels of SAH groups but were absent in the
purpurogallin group. IL-1β,
IL-6, and TNF-α in the SAH only and SAH plus vehicle groups were significantly elevated (P < 0.01). Purpurgallin dose-dependently reduced
HMGB1 protein expression. Likewise, high dose
purpurogallin reduced TNF-α and
HMGB1 mRNA levels. In conclusion,
purpurogallin exerts its
neuroinflammation effect through the dual effect of inhibiting
IL-6 and TNF-α
mRNA expression and reducing
HMGB1 protein and
mRNA expression. This study supports
purpurogallin could attenuate both proinflammatory
cytokines and late-onset
inflammasome in SAH induced vasospasm.