Apigenin-d5 is an internal standard for the quantificaiton of apigenin by GC- or LC-MS. Apigenin is a flavonoid compound found in many fruits and vegetables that selectively inhibits casein kinase 2 (CK2). Apigenin inhibits CK2 activity in the renal cortex with an IC50 value of 30 µM to improve renal function in a rat model of glomerulonephritis.1 CK2 inhibition by 20 µM apigenin decreases the degradation of IκBα and down-regulates NF-κB levels in WEHI-231 cells.2 Apigenin, at 5 µM, is a potent inhibitor of the synthesis of the inflammatory mediators nitric oxide and prostaglandin E2, reducing inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression by 56% and 64%, respectively, in the macrophage cell line J774A.1.3
1.Yamada, M., Katsuma, S., Adachi, T., et al.Inhibition of protein kinase CK2 prevents the progression of glomerulonephritisProceedings of the National Academy of Sciences of the United States of America102(21)7736-7741(2005) 2.Shen, J., Channavajhala, P., Seldin, D.C., et al.Phosphorylation by the protein kinase CK2 promotes calpain-mediated degradation of IκBα1Journal of Immunology1679)4919-4925(2001) 3.Raso, G.M., Meli, R., Di Carlo, G., et al.Inhibition of inducible nitric oxide synthase and cyclooxygenase-2 expression by flavonoids in macrophage J774A.1Life Sciences68(8)921-931(2001)