title: Simvastatin Attenuates Oxidative Stress, NF-κB Activation, and Artery Calcification in LDLR-/- Mice Fed with High Fat Diet via Down-regulation of Tumor Necrosis Factor-α and TNF Receptor 1.
abstract: Simvastatin (SIM) is anti-inflammatory. We used low density lipoprotein receptor knockout (LDLR-/-) mice and human aortic smooth muscle cells (HASMCs) as model systems to study the effect of SIM on arterial calcification and to explore the potential mechanisms contributing to this protective effect. High-fat diet (HFD) caused the LRLR -/- to develop dyslipidemia, diabetics, atherosclerosis and aortic smooth muscle calcification. SIM, N-acetyl cysteine (NAC, a ROS scavenger) and apocynin (APO, a NADPH oxidase inhibitor) did not significantly retard the development of dyslipidemia or diabetic. However, those treatments were still effective in attenuating the HFD-induced atherosclerosis and aortic smooth muscle calcification. These findings suggest that the protective effect of SIM against aortic calcification is not contributed by the cholesterol lowering effect. SIM, NAC and APO were found to attenuate the HFD induced elevation of serum TNF-α, soluble TNFR1 (sTNFR1), 3-nitro-tyrosine. We hypothesized that the pro-inflammatory cytokine, oxidative stress and TNFR1 played a role in inducing aortic calcification. We used HASMC to investigate the role of TNF-α, oxidative stress and TNFR1 in inducing aortic calcification and to elucidate the mechanism contributes the protective effect of SIM against aortic calcification. We demonstrated that treating HASMC with TNF-α induced cell Ca deposit and result in an increase in ALP, NADPH oxidase activity, NF-kB subunit p65, BMP2, MSX2, and RUNX2 expression. SIM suppressed the TNF-α induced activation of NADPH oxidase subunit p47, the above-mentioned bone markers and TNFR1 expression. Furthermore, p65, p47 and TNFR1 siRNAs inhibited the TNF-α-mediated stimulation of BMP-2, MSX2, RUNX2 expression. SIM, APO, and NAC either partially inhibit or completely block the TNF-α induced H2O2 or superoxide production. These results suggest that SIM may, independent of its cholesterol-lowering effect, suppresses the progression of vascular diseases through the inhibition of the inflammation mediators TNF-α and TNFR1.
authors.affiliation: Division of Central Laboratory, Department of Pathology and Laboratory Medicine, Taipei Veterans General Hospital; 2. Department of Biotechnology and Laboratory Science in Medicine and Institute of Biotechnology in Medicine, National Yang-Ming University, Taipei,  Taiwan.|Department of Biotechnology and Laboratory Science in Medicine and Institute of Biotechnology in Medicine, Taipei, Taiwan.
authors.forename: Chih-Pei
authors.initials: CP
authors.lastname: Lin
authors.affiliation: Division of Cardiology, Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan.|Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Po-Hsun
authors.initials: PH
authors.lastname: Huang
authors.affiliation: Volunteer Scientist, E-da Hospital, Kaohsiung, Taiwan.
authors.forename: Chung Fang
authors.initials: CF
authors.lastname: Lai
authors.affiliation: Division of Cardiology, Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan.|Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.|Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Jaw-Wen
authors.initials: JW
authors.lastname: Chen
authors.affiliation: Division of Cardiology, Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan.|Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.|Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Shing-Jong
authors.initials: SJ
authors.lastname: Lin
authors.affiliation: Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Jia-Shiong
authors.initials: JS
authors.lastname: Chen
mesh_terms: D000818:Animals; D001161:Arteriosclerosis / Q000378:metabolism* / Q000473:pathology; D002114:Calcinosis / Q000378:metabolism*; D059305:Diet, High-Fat; D015536:Down-Regulation; D055786:Gene Knockout Techniques; D006801:Humans; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D016328:NF-kappa B / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects*; D011973:Receptors, LDL / Q000235:genetics; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D019821:Simvastatin / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*
chemical_list: D016328:NF-kappa B; D011973:Receptors, LDL; D047888:Receptors, Tumor Necrosis Factor, Type I; D014409:Tumor Necrosis Factor-alpha; D019821:Simvastatin