Depression is a common mental disorder that seriously harms human physical and mental health. As society develops, the increase in daily pressures and the role of various other factors have made the incidence of depression increase year by year. However, there is a lack of drugs to treat depression that have a fast onset, significant effects, and few side effects. Some traditional natural herbal medicines are used to relieve depression and calm emotions. A growing number of studies have shown that herbal therapies for depression can be considered as potential rehabilitation approaches, especially natural products and herbal formulas, which provide a new perspective for the treatment of depression.

Neurotransmitters, synaptic plasticity, circulating extracellular vesicles, and epigenetic mechanisms play important roles in the altered processing in depression. Pathological changes in synaptic plasticity impair synaptic computation, which controls the information flow through the release of neurotransmitters for the complex information processing necessary to drive adaptive behaviors. On a molecular level, modifications in the neuronal epigenome mediate gene-environmental interactions, which are required for activity-dependent regulation of release of neurotransmitters and synaptic plasticity. Therefore, neurotransmitters, synaptic plasticity, and epigenetic mechanisms play important roles in the pathogenesis and therapeutic targets of depression and depressive behavior from macro- to micro-levels.

The aim of this Special Issue is to collate a range of clinical research and experimental studies on the role of neurotransmitters, synaptic plasticity, and epigenetic mechanisms in relation to herbal therapies, including natural products and herbal formulas, for the treatment of depression. We also welcome high-level reviews on the mechanisms of herbal therapies for depression.

Potential topics include but are not limited to the following:

• Natural products and herbal formulas of neuromodulation for depression and depressive behaviors
• Herbal medicines for effective neuromodulation of neurotransmitters
• Neuromodulation of synaptic plasticity using herbal medicine approaches
• Epigenetic mechanisms of neuromodulation via herbal medicines
• Complementary and Alternative Therapies in depression treatment
• Correspondence between formulas and pattern in depression treatment
• Evidence-based pattern syndrome: herbal medicine in depression treatment
• Pharmacogenomic evaluation of herbal drugs for depression
• Natural compounds as effective neuromodulators of neurotransmission and depression
• Network pharmacology of herbal medicines for depression and neurotransmitter modulation
• Circulating Extracellular Vesicles of neuromodulation via herbal medicines and natural products
• Cell and animal models in herbal medicine treatment of depression