BACKGROUND

Among people with post-traumatic stress disorder (PTSD), there is an increased prevalence of age-related diseases. However, the biological mechanisms underlying this phenomenon remain incompletely understood.

METHODS

The expression of cystathionine β-synthase (CBS), one of the main enzymes for endogenous hydrogen sulfide (HS) production in the brain, is age-dependent. In this study, we examined the influence of CBS/HS on anxiety and depression-like behavior following the inescapable foot shock (IFS) procedure during early adolescence (postnatal days 28-35) or adulthood (postnatal days 63-70).

RESULTS

Our results showed that adult PTSD mice exhibited more pronounced decreases in HS content and CBS expression in the hippocampus, which were associated with anxiety and depression-like behavior compared with adolescent PTSD mice. Administration of exogenous HS significantly improved anxiety and depression-like behavior, mitigated synaptic plasticity deficits, and activated the CREB/BDNF signaling pathway in the hippocampus of adolescent PTSD mice. In addition, we found that high dose HS could improve anxiety and depression-like behavior, mitigate synaptic plasticity deficits, and activate the CREB/BDNF signaling pathway, as well as increase HS levels in the hippocampus. In contrast, injection of CBS antibody in the hippocampus of adult mice increased anxiety and depressive-like behavior.

CONCLUSION

These results suggest that CBS/ HS modulates PTSD-like behaviors in an age-dependent manner and may promote synaptic plasticity through activation of the CREB/BDNF pathway in the hippocampus of mice after IFS exposure.