Metal Ions in Longgu (Fossilized Bone) as a Natural Synergistic Network for Multi-Target Therapy in Psychiatric Disorders.

Longgu (fossilized bone), a mineral medicine in traditional Chinese medicine, has been used for centuries to treat symptoms resembling modern anxiety and insomnia. This review evaluates the hypothesis that Longgu's therapeutic effects arise from a synergistic network of its constituent metal ions. We synthesized evidence from chemical analyses, pharmacological studies of Ca, Mg, Zn, Fe, Cu, and Mn, and clinical trials of Longgu-containing formulations. The metal ions form an integrated network exhibiting three emergent properties. First, ionostatic balance is achieved through Ca/Mg-mediated regulation of neuronal excitability. Second, cross-pathway synergy occurs where zinc concurrently modulates neurotransmission and promotes neuroplasticity via BDNF. Third, systemic integration involves zinc and manganese co-regulating the gut-brain axis. Clinical studies demonstrate that Longgu-containing formulations improve outcomes in depression, anxiety, and insomnia, particularly for comorbid conditions, and show synergistic effects when combined with conventional antidepressants. This network pharmacology framework repositions Longgu as a model for developing multi-target therapeutics, offering a strategy to overcome limitations of single-target psychiatric drugs.