Hydrogen sulfide inhibits lipopolysaccharide-based neuroinflammation-induced astrocyte polarization after cerebral ischemia/reperfusion injury

The effect of lipopolysaccharide (LPS)-based neuroinflammation following cerebral ischemia/reperfusion (I/R) on the genotypic transformation of reactive astrocytes and its relationship with endogenous hydrogen sulfide (H 2 S) were investigated in present study. We found that LPS promoted the cerebral I/R-induced A1 astrocytes proliferation in mouse hippocampal tissues and deteriorated the reduction of hydrogen sulfide (H 2 S) content in mouse sera, H 2 S donor NaHS could inhibit A1 astrocytes proliferation. Similarly, knockout of cystathionine γ-lyase (CSE), one of endogenous H 2 S synthases, likewise up-regulated the cerebral I/R-induced A1 astrocytes proliferation, which could also be blocked by NaHS. Besides, supplement with H 2 S promoted the A2 astrocytes proliferation in hippocampal tissues of CSE knockout (CSE KO) mice or LPS-treated mice following cerebral I/R. In the oxygen glucose deprivation/reoxygenation (OGD/R) model of astrocytes, H 2 S also promoted the transformation of astrocytes into A2 subtype. Moreover, we found that H 2 S could up-regulate the expression of α-subunit of large-conductance Ca 2+ -activated K + (BK Ca ) channels in astrocytes, and the channel opener BMS-191011 likewise promoted the transformation of astrocyte into A2 subtype. In conclusion, H 2 S inhibits the proliferation of A1 astrocytes induced by LPS-based neuroinflammation following cerebral I/R and promotes the transformation of astrocytes into A2 subtype, which may be related to up-regulation of BK Ca channels.