GDF11 mediates H 2 S to prevent chronic stress-induced cognitive impairment by reducing hippocampal NLRP3/caspase-1-dependent pyroptosis.

BACKGROUND: We previously revealed that hydrogen sulfide (H2 S) attenuates chronic stress-induced cognitive impairment, but the underlying mechanism needs to be further clarified. Growth differentiation factor 11 (GDF11) plays an important regulatory role in cognitive function and that hippocampal NLRP3/caspase-1-mediated pyroptosis contributes to the pathogenesis of cognitive impairment. Hence, this research aimed to explore whether promoting GDF11 levels and suppressing hippocampal NLRP3/caspase-1-mediated pyroptosis mediate H2 S to alleviate chronic stress-induced cognitive impairment.

METHODS: Sprague-Dawley rats were subjected to unpredictable chronic mild stress lasting four weeks to establish an animal model of chronic stress-induced cognitive impairment. Behavioral performance was assessed by the Y-maze test and the novel object recognition test. The expression levels of proteins were analyzed by Western blot analysis. The levels of IL-1β and IL-18 in the hippocampus were measured by ELISA.

RESULTS: NaHS upregulated the expression of GDF11 in the hippocampus of chronic unpredictable mild stress (CUMS)-exposed rats. Silencing GDF11 blocked NaHS-improved cognitive impairment in CUMS-exposed rats, according to the Y-maze test and the novel object recognition test. Furthermore, NaHS mitigated NLRP3/caspase-1-mediated pyroptosis in the hippocampus of CUMS-exposed rats and this effect was reversed by silencing GDF11. Moreover, overexpression of GDF11 alleviated CUMS-induced cognitive impairment and NLRP3/caspase-1-mediated hippocampal pyroptosis.

CONCLUSIONS: GDF11 mediates H2 S to attenuate chronic stress-induced cognitive impairment via inhibiting hippocampal NLRP3/caspase-1-mediated pyroptosis.