title: Genistein inhibits TNF-α-induced endothelial inflammation through the protein kinase pathway A and improves vascular inflammation in C57BL/6 mice.
abstract: Genistein, a soy isoflavone, has received wide attention for its potential to improve vascular function, but the mechanism of this effect is unclear. Here, we report that genistein at physiological concentrations (0.1 μM-5 μM) significantly inhibited TNF-α-induced adhesion of monocytes to human umbilical vein endothelial cells, a key event in the pathogenesis of atherosclerosis. Genistein also significantly suppressed TNF-α-induced production of adhesion molecules and chemokines such as sICAM-1, sVCAM-1, sE-Selectin, MCP-1 and IL-8, which play key role in the firm adhesion of monocytes to activated endothelial cells (ECs). Genistein at physiologically relevant concentrations didn't significantly induce antioxidant enzyme activities or scavenge free radicals. Further, blocking the estrogen receptors (ERs) in ECs didn't alter the preventive effect of genistein on endothelial inflammation. However, inhibition of protein kinase A (PKA) significantly attenuated the inhibitory effects of genistein on TNF-α-induced monocyte adhesion to ECs as well as the production of MCP-1 and IL-8. In animal study, dietary genistein significantly suppressed TNF-α-induced increase in circulating chemokines and adhesion molecules in C57BL/6 mice. Genistein treatment also reduced VCAM-1 and monocytes-derived F4/80-positive macrophages in the aorta of TNF-α-treated mice. In conclusion, genistein protects against TNF-α-induced vascular endothelial inflammation both in vitro and in vivo models. This anti-inflammatory effect of genistein is independent of the ER-mediated signaling machinery or antioxidant activity, but mediated via the PKA signaling pathway.
authors.affiliation: Department of Biology, University of North Carolina at Greensboro, Greensboro, 27412, USA. Electronic address: z_jia@uncg.edu.
authors.forename: Zhenquan
authors.initials: Z
authors.lastname: Jia
authors.forename: Pon Velayutham Anandh
authors.initials: PV
authors.lastname: Babu
authors.forename: Hongwei
authors.initials: H
authors.lastname: Si
authors.forename: Palanisamy
authors.initials: P
authors.lastname: Nallasamy
authors.forename: Hong
authors.initials: H
authors.lastname: Zhu
authors.forename: Wei
authors.initials: W
authors.lastname: Zhen
authors.forename: Hara P
authors.initials: HP
authors.lastname: Misra
authors.forename: Yunbo
authors.initials: Y
authors.lastname: Li
authors.forename: Dongmin
authors.initials: D
authors.lastname: Liu
mesh_terms: D000818:Animals; D017868:Cyclic AMP-Dependent Protein Kinases / Q000187:drug effects / Q000502:physiology*; D042783:Endothelial Cells; D004730:Endothelium, Vascular; D019833:Genistein / Q000494:pharmacology*; D007249:Inflammation / Q000209:etiology* / Q000517:prevention & control*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D015398:Signal Transduction; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors* / Q000502:physiology
chemical_list: D047428:Protein Kinase Inhibitors; D014409:Tumor Necrosis Factor-alpha; D019833:Genistein; D017868:Cyclic AMP-Dependent Protein Kinases
keywords: 5,5-dimethylpyrroline-N-oxide; CAT; CXCL1/KC; DMPO; EPR; ER; Endothelial cells; FBS; GPx; GR; GSH; GST; Genistein; HUVECs; ICAM-1; IL-8; MCP-1; MCP-1/JE; PKA; PTK; Protein kinase A; ROS; SOD; TNF-α; VCAM-1; Vascular inflammation; catalase; chemokine (C-X-C motif) ligand 1; electron paramagnetic resonance; estrogen receptor; fetal bovine serum; glutathione; glutathione peroxidase; glutathione reductase; glutathione transferase; human umbilical vein endothelial cells; intercellular adhesion molecule-1; interleukin-8; monocyte chemotactic protein-1; mouse/monocyte chemotactic protein-1/JE; protein kinase A; protein tyrosin kinase; reactive oxygen species; sE-Selectin; sICAM-1; sVCAM-1; soluble E-Selectin; soluble intercellular adhesion molecule-1; soluble vascular adhesion molecule-1; superoxide dismutase; tumor necrosis factor-α; vascular adhesion molecule-1