Table 3.

Natural compounds with therapeutic potential for PD treatment

Category	Name	Formula	Pharmacological effects	Major targets
Phenol	Curcumin	C21H20O6	TNF-α ↓ , caspase activity ↓ , inflammatory cytokines ↓ , inflammatory enzymes ↓ , cycloxygenase-2 ↓ , GFAP ↓ , cyclin D1 ↓ , JNK phosphorylation ↓ , cell apophagy ↓ , BDNF ↑	Trk/PI3K, JNK
	Resveratrol	C14H12O3	Cytochrome C ↓ , apoptosis ↓ , ROS ↓ , α-synuclein ↓ , autophagic flux ↑ , Bax/Bcl-2 ↑ , antioxidant defenses↑	PI3K/Akt, SIRT 1, MAPK
Alkaloid	Berberine	C20H18NO4+	Neurons degeneration ↓ , motor impairment ↓ , α-synuclein ↓ , autophagy ↑ , L-DOPA ↑	AMPK,
	Isorhynchophylline	C22H28N2O4	α-synuclein ↓ , autophagy↑	ASK1/JNK
Flavonoid	Puerarin	C21H20O9	Caspase-3 ↓ , p53↓	Fyn/GSK-3β, PI3K/Akt
	Baicalein	C15H10O5	Caspase-3 ↓ , α-synuclein ↓ , neuroinflammation ↓ , ROS ↓ , Bax/Bcl-2↑	NLRP3/caspase-1/gasdermin D, BDNF/TrkB/CREB
Terpenoid	Celastrol	C29H38O4	Neuroinflammation ↓ , motor symptoms ↓ , neurodegeneration ↓ , autophagy ↑ , autophagosome biogenesis↑	MAPK, Nrf2-NLRP3-caspase-1
	Triptolide	C20H24O6	Microglial activation ↓ , proinflammatory cytokines ↓ , α-synuclein↓	miR155-5p/SHIP1, NF-κB
Saponin	Ginsenoside Rb1	C54H92O23	hippocampal CA3 α‐synuclein ↑ , glutamate ↑ , DA ↑ , neuroinflammation↓	NF-κB
	Ginsenoside Rg3	C42H72O13	DA ↑ , ROS ↓ , hydroxylase-positive neurons↑