ABSTRACT
@#【Objective】ThisstudyaimstoinvestigatewhetherrutecarpinehasaneffectoncalcificationofVSMCand itsunderlyingmechanism.【Methods】InvitromodelofratVSMCcalcificationwasusedinthisstudy.Rutecarpineat differentconcentrationswasusedtotreatculturedratVSMC.Theexpressionof Runx2，BMP2 and Osterix wasanalyzed byqRT-PCRandmineraldepositionwasdetectedbyalizarinredstaining.Inaddition，weexaminedtheeffectofrutecar⁃ pineonSirtuin-1（Sirt1）expressioninVSMCandtheeffectofSirt1inhibitoronVSMCcalcification.【Results】Alizarinred stainingandcalciumcontentassayshowedthatrutecarpineatdifferentconcentrationssignificantlyreducedcalcificationof ratVSMCinducedbyhighphosphorusandhighcalcium（136±10，75±6，52±6，31±5.29，P<0.05）.Usageofrutecar⁃ pinedecreasedtheactivityofALP，anosteogenicdifferentiationmolecularmarker，anddown-regulatedtheexpressionof Runx2（2.85±0.25，1.75±0.18，1.62±0.13，1.36±0.16，P <0.05），BMP2（3.2±0.32，1.85±0.17，1.65±0.15，1.43± 0.12，P<0.05）andOsterix（2.60±0.27，1.82±0.16，1.55±0.15，1.36±0.17，P<0.05），suggestingthatrutecarpineinhib⁃ ited osteogenic differentiation of VSMC. In addition，high phosphorus and high calcium down-regulated the expres⁃ sionofSirt1inVSMC.qRT-PCRandwesternblotanalysisconfirmedthatrutecarpineup-regulatedtheexpressionof Sirt1atbothmRNA（0.35±0.06，0.75±0.11；0.22±0.08，0.87±0.13，P <0.05）andproteinlevels（0.38±0.09，0.71±0.13，P<0.05）.QuantificationofcalciumcontentanalysisshowedinhibitionofSirt1byEX-527blockedtheinhibitory effectofrutecarpineonVSMCcalcification（138±13，36±7，87±8，P<0.05） .【Conclusion】Wedemonstratethatrutecar⁃ pineattenuatesVSMCcalcificationviaup-regulationofSirt1.
ABSTRACT
AIM:Toinvestigatetheeffectsofcalcitoningene-relatedpeptide(CGRP)onmyocardinexpres-sion and phenotypic switch in vascular smooth muscle cells ( VSMCs) .METHODS:VSMCs were obtained by aortic tissue adherent culture and treated with angiotensin Ⅱ( AngⅡ) , AngⅡ+CGRP or AngⅡ+CGRP +CGRP8-37 .The protein expression of myocardin and the phenotypic proteins of the VSMCs was detected by Western blot .RESULTS:The expres-sion of myocardin in cultured VSMCs showed downregulation along with time expansion .The protein level of myocardin was higher at 48 h and 72 h than that at baseline in the cultured VSMCs (P<0.05).However, the myocardin was lower at 48 h and 72 h than that at baseline after treatment with CGRP in cultured VSMCs (P<0.05).Furthermore, at 48 h in cul-tured VSMCs, the myocardin decreased along with α-smooth muscle actin (α-SMA) (P<0.05), and osteopontin (OPN) increased (P<0.05) in AngⅡ group compared with control group .After treatment with CGRP, the levels of myocardin andα-SMA become higher ( P <0.05 ) but OPN was lower ( P <0.05 ) in CGRP group than those in AngⅡ group. CGRP8-37 abrogated CGRP-induced increase in myocardin and α-SMA and decrease in OPN in CGRP 8-37 group compared with CGRP group .CONCLUSION: CGRP may regulate the phenotypic switch of the VSMCs and maintain the cells in contractile phenotype through the upregulation of myocardin protein , which may be accomplished by the combination of CGRP and its receptor .