8-Oxycoptisine is an isoquinoline alkaloid that has been found inCoptis chinensisand has anticancer and gastroprotective activities.^1,2,3It is an active metabolite of coptisine formed by gut microbiota.¹8-Oxycoptisine is cytotoxic against NCI-N87 gastric, but not Caco-2 colon, cancer cells (IC₅₀s = 20.31 and >100 µM, respectively).²It reverses resistance to paclitaxel in non-multidrug-resistant SKOV3 cells, as well as in HCT-15 cells, which endogenously express high levels of P-glycoprotein (P-gp), with EC₅₀values of 0.3 and 0.5 ng/ml, respectively.³It reduces colonic shortening and inflammatory cell infiltration in a mouse model of ulcerative colitis induced by dextran sulfate when administered at doses of 50 or 100 mg/kg.¹

1.Ai, G., Huang, Z., Cheng, J., et al.Gut microbiota-mediated transformation of coptisine Into a novel metabolite 8-oxocoptisine: Insight into its superior anti-colitis effectFront. Pharmacol.1212:639020(2021) 2.Qian, P., and Yang, X.-W.Five new alkaloids from Coptidis Rhizoma-Euodiae Fructus couple and their cytotoxic activities against gastrointestinal cancer cellsFitoterapia9374-80(2014) 3.Min, Y.D., Yang, M.C.M., Lee, K.H., et al.Protoberberine alkaloids and their reversal activity of P-gp expressed multidrug resistance (MDR) from the rhizome of Coptis japonica MakinoArch. Pharm. Res.29(9)757-761(2006)