Preconditioning with hydrogen sulfide ameliorates cerebral ischemia/reperfusion injury in a mouse model of transient middle cerebral artery occlusion.

Ischemic stroke and reperfusion injury are a common and serve medical situation in the elderly population. HS is a gas neuromodulator which also possesses anti-oxidant and anti-inflammatory properties, and is found to play neuroprotective effect in neurodegenerative diseases. This study investigated the effect of endogenous and exogenous HS in a mouse model of ischemic stroke. 129P2-Cbs/J mice with heterozygous mutants in HS generating enzyme cystathionine β-synthase were used to study the effect of endogenous HS. HS donor NaHS was used as exogenous HS. Animals were pretreated with HS and then subjected to middle cerebral artery occlusion surgery. Behavioral outcome was evaluated by novel object recognition test. Inflammatory cytokines were measured using ELISA. Western blot was used to detect the activation of NF-κB. Aged 129P2-Cbs/J mice showed exaggerated inflammation and more severe cognitive impairment after ischemia, while exogenous HS treatment inhibited inflammation and attenuated behavioral impairment. The anti-inflammatory effect of HS was mediated by inhibiting NF-κB. Our findings suggest that both endogenous and exogenous HS are involved in the neuroprotection against ischemia/reperfusion-induced cerebral injury.