Table 5.

Natural saponins and quinones with pharmacological potential.

Name	Source	Antioxidant stress	Anti-inflammatory	Antiapoptosis	Promote matrix anabolism	Promote proliferation	Signal path	Type of study	References
Ginsenosides	Ginseng genus			Flow cytometric analysis↓	Collagen II, aggrecan↑	CCK-8↑, cyclin D1↓	Wnt/β-catenin	A	[148]
		ROS↓	TNF-α↓	Caspase-3, Bax↓, Bcl-2↑	Collagen II, aggrecan↑, MMP3, ADAMTS-5↓	CCK-8/EdU↑	NF-κB	B	[149]
Plumbagin	Graphite	ROS↓, GSH, SOD2↑	TNF-α, IL-1β, IL-6↓	Caspase-3/9↓		MTT	NF-κB and Nrf2	A	[151]

A: rat model of NP in vitro. B: human model of NP in vitro.