Arecoline Alleviates Depression via Gut–Brain Axis Modulation, Neurotransmitter Balance, Neuroplasticity Enhancement, and Inflammation Reduction in CUMS Mice

, and regulated serum metabolites associated with tryptophan metabolism, neurotransmitter synthesis, and oxidative stress. These findings demonstrate that arecoline exerts its antidepressant effects via a multitargeted approach involving the gut-brain axis, neurotransmitter modulation, and neuroplasticity enhancement. This study highlights arecoline as a promising therapeutic candidate for depression, emphasizing its potential to address both central and peripheral mechanisms.