title: Puerarin activates endothelial nitric oxide synthase through estrogen receptor-dependent PI3-kinase and calcium-dependent AMP-activated protein kinase.
abstract: The cardioprotective properties of puerarin, a natural product, have been attributed to the endothelial nitric oxide synthase (eNOS)-mediated production of nitric oxide (NO) in EA.hy926 endothelial cells. However, the mechanism by which puerarin activates eNOS remains unclear. In this study, we sought to identify the intracellular pathways underlying eNOS activation by puerarin. Puerarin induced the activating phosphorylation of eNOS on Ser1177 and the production of NO in EA.hy926 cells. Puerarin-induced eNOS phosphorylation required estrogen receptor (ER)-mediated phosphatidylinositol 3-kinase (PI3K)/Akt signaling and was reversed by AMP-activated protein kinase (AMPK) and calcium/calmodulin-dependent kinase II (CaMKII) inhibition. Importantly, puerarin inhibited the adhesion of tumor necrosis factor (TNF)-α-stimulated monocytes to endothelial cells and suppressed the TNF-α induced expression of intercellular cell adhesion molecule-1. Puerarin also inhibited the TNF-α-induced nuclear factor-κB activation, which was attenuated by pretreatment with N(G)-nitro-L-arginine methyl ester, a NOS inhibitor. These results indicate that puerarin stimulates eNOS phosphorylation and NO production via activation of an estrogen receptor-mediated PI3K/Akt- and CaMKII/AMPK-dependent pathway. Puerarin may be useful for the treatment or prevention of endothelial dysfunction associated with diabetes and cardiovascular disease.
authors: Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea.
authors: Yong Pil
authors: YP
authors: Hwang
authors: Hyung Gyun
authors: HG
authors: Kim
authors: Tran Thi
authors: TT
authors: Hien
authors: Myung Ho
authors: MH
authors: Jeong
authors: Tae Cheon
authors: TC
authors: Jeong
authors: Hye Gwang
authors: HG
authors: Jeong
mesh_terms: D000091162:AMP-Activated Protein Kinase Kinases; D015153:Blotting, Western; D002118:Calcium / Q000032:analysis; D054737:Calcium-Calmodulin-Dependent Protein Kinase Kinase / Q000378:metabolism / Q000502:physiology; D002460:Cell Line; D042783:Endothelial Cells / Q000737:chemistry / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis; D007529:Isoflavones / Q000494:pharmacology*; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology*; D010766:Phosphorylation / Q000187:drug effects; D011494:Protein Kinases / Q000378:metabolism / Q000502:physiology*; D060888:Real-Time Polymerase Chain Reaction; D011960:Receptors, Estrogen / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
chemical_list: D000091162:AMP-Activated Protein Kinase Kinases; D002118:Calcium; D054737:Calcium-Calmodulin-Dependent Protein Kinase Kinase; D018799:Intercellular Adhesion Molecule-1; D007529:Isoflavones; D052250:Nitric Oxide Synthase Type III; D019869:Phosphatidylinositol 3-Kinases; D011494:Protein Kinases; D011960:Receptors, Estrogen; C033607:puerarin