TH and Parkinson disease: Polymannuronic acid, a natural alginate compound derived from brown seaweed, had a neuroprotective effect on an MPTP-induced PD animal model by improving motor function, preventing dopaminergic neuronal loss by increasing TH expression in the midbrain, enhancing serotonin (5-HT) and 5-hydroxyindole acetic acid (5-HIAA) levels in the striatum, and increasing the polymannuronic acid levels, which resulted in potential anti-inflammatory effects in PD mice [64].