IL18 and major depressive disorder: reported that patients with higher IL-1β levels were more likely to exhibit resistance to antidepressant treatments, suggesting that IL-1β may serve as a predictive marker for therapeutic responses in depression (26).IL-18, another pro-inflammatory cytokine belonging to the IL-1 family, is often regarded as a key molecule acting synergistically with IL-1β in studies of depression and neuroinflammation (27, 28).In the present study, LPS treatment significantly increased serum IL-1β and IL-18 levels in rats, whereas taVNS intervention markedly reduced its expression.