Moringa oleifera Lam. seed lectin (WSMoL) reduces chronic stress-induced anxiety and depression in mice by lessening inflammation and balancing brain chemicals

Phyto-based treatments for anxiety and depression are gaining attention. The efficacy of the water-soluble Moringa oleifera seed lectin (WSMoL) in reducing acute anxiolytic and depressive-like behaviors in mice has been previously demonstrated. In the present study, it was evaluated the effects of WSMoL on reducing anxiety and depressive-like symptoms in a mouse model of unpredictable chronic mild stress (UCMS). The animals were divided into groups and exposed to a four-week UCMS regimen. Following this, the mice received daily intraperitoneal injections of vehicle (non-stressed and UCMS control groups), WSMoL (2 or 4 mg/kg), or fluoxetine (10 mg/kg) for 21 days. Neurobehavioral tests included the open field test and elevated plus maze test to assess anxiety-like behavior, and the tail suspension test and sucrose preference test to evaluate depression-like behavior. Biochemical analyses measured serum corticosterone and cytokines as well brain levels of cytokines and monoamines. All tests indicated that WSMoL significantly (p < 0.05) reversed the anxiety and depression-like behaviors induced by UCMS. The stress protocol increased serum corticosterone levels and WSMoL treatment was not able to normalize corticosterone secretion. WSMoL treatment reduced serum and brain levels of IL-2, IL-6, and TNF-α, indicating reduced neuroinflammation, and increased brain levels of dopamine, serotonin, and noradrenaline. In summary, WSMoL mitigated UCMS-induced anxiety and depression-like behaviors by reducing neuroinflammation and modulating brain monoamine levels.