3,8’-Biapigenin is a polyketide synthase-derived biflavonoid that has been found inHypericumand has diverse biological activities.^1,2,3,4,5It inhibits protein tyrosine phosphatase 1B (PTP1B; IC₅₀= 4.5 µM) and stimulates glucose uptake in 3T3-L1 adipocyte cells when used at concentrations of 5 and 10 µM.²3,8’-Biapigenin inhibits the cytochrome P450 (CYP) isoforms CYP3A4, CYP2C9, and CYP1A2 (K_is = 0.038, 0.32, and 0.95 µM, respectively).³It reverses cell death induced by kainate and NMDA in isolated rat embryonic hippocampal neurons when used at a concentration of 10 µM.⁴3,8’-Biapigenin (8 mg/kg) decreases carrageenan-induced paw edema and protects against gastric lesions induced by indomethacin in rats.⁵

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