Mollugin: A Comprehensive Review of Its Multifaceted Pharmacological Properties and Therapeutic Potential

The substantial interest in plant-based drugs or plant-derived phytocompounds drives researchers to conduct comprehensive investigations on their therapeutic properties. Mollugin, one of the major active constituents of Rubia cardifolia, has been well-studied for its pharmacological properties, demonstrating potent anti-inflammatory properties by suppressing the TAK-1-mediated activation of NF-κB/MAPK and enhancing the Nrf2/HO-1-mediated antioxidant response. It exhibits strong anticancer effects through ferroptosis via IGF2BP3/GPX4 pathways, induces mitochondrial apoptosis, and targets NF-κB, ERK, and PI3K/Akt/mTOR to suppress tumor progression. Mollugin also inhibits JAK2/STAT and PARP1 pathways, suppressing IL-1β expression via the modulation of ZFP91. Moreover, it regulates the MAPK/p38 pathway, promotes neuroprotection, and improves cognitive performance through GLP-1 receptor activation. Mollugin promotes osteogenesis by activating the BMP-2/Smad1/5/8 signaling pathway and downregulates MAPK, Akt, and GSK3β expression, leading to the inhibition of osteoclastogenesis. It overcomes multidrug resistance by downregulating MDR1/P-gp, CREB, NF-κB, and COX-2 through AMPK activation. Its antibacterial effect is mediated by strong binding to FUR, UDP, and IpxB proteins in Enterobacter xiangfangensis. Mollugin mitigates Klebsiella pneumoniae infection, suppresses adipogenesis without causing cytotoxicity, and protects endothelial cells via the BDNF/TrkB-Akt signaling pathway. Synthetic derivatives of mollugin, such as oxomollugin and azamollugin, have shown enhanced anticancer and anti-inflammatory effects by regulating EGFR, PKM2, TLR4/MyD88/IRAK/TRAF6, and NF-κB/IRF3 pathways with improved solubility and stability. Collectively, these findings emphasize the broad-spectrum activity of mollugin. This review provides a critical interpretation of the mechanistic pathways regulated by mollugin and its derivatives, emphasizing their pharmacological significance and exploring their potential for future translation as multitarget drug candidates.