ABSTRACT
@#【Objective】The aim of this study is to investigate whether Fuzi polysaccharide（FPS）inhibits calcification of vascular smooth muscle cells（VSMC）and its underlying mechanism involving ceramide signaling.【Methods】We used Ox- LDL to induce in vitro model of human VSMC calcification in this study. FPS at different concentrations was used to treat human VSMC. Cell calcification was assessed by alizarin red staining. The mRNA expressions of osteogenic differentiation markers including Msx2，Osterix and BMP2，and contractile marker SMA were analyzed by qRT- PCR. The protein expressions of Msx2 and BMP2 were analyzed by western blot. Cell apoptosis was examined by TUNEL. Additionally，we investigated the effect of FPS on ceramide levels and N- SMase activity in VSMC. 【Results】We found that FPS inhibits Ox- LDL- induced VSMC apoptosis and calcification. Ceramide participates in Ox- LDL- induced apoptosis and calcification of VSMC. FPS reduces N- SMase activity and ceramide levels in Ox- LDL- treated VSMC. Collectively ， reducing N-SMase activity and ceramide levels could become a promising strategy for the treatment of vascular calcification.【Conclusion】We demonstrate that FPS attenuates VSMC calcification via targeting ceramide signaling.
ABSTRACT
[Objective] Vascular calcification is a gene-regulated biological process similar to bone formation.It is very common in the patients with chronic kidney disease.Neutral sphingomyelinase 2 (nSMase2) is a key regulator of bone development,and is responsible for ceramide generation through sphingomyelin hydrolysis,but the role of nSMase2 in vascular calcification remains unclear.The aim of this study is to determine whether nSMase2 regulates high calcium and phosphate-induced calcification of vascular smooth muscle cells (VSMC).[Methods] In vitro model of human VSMC calcification was used in this study and high calcium and phosphate were used to induce calcification of VSMCs.GW4869 was used to inhibit nSMase2 activity and nSMase2 was knockdowned in cultured VSMC using nSMase2 siRNA.The expression of Runx2,BMP2 and Osterix was analyzed by qRT-PCR and calcification was assessed by alizarin red staining.[Results] We found that nSMase2 expression and ceramide levels were increased in the process of VSMC calcification (P＜0.05).Inhibition of nSMase2 activity by GW4869 and knockdown of nSMase2 attenuated high calcium and phosphate-induced VSMC calcification and down-regulated the expression level of Runx2,BMP2 and Osterix (P＜0.05).By contrast,ceramide accelerated rat VSMC calcification and increased ALP activity (P＜0.05).[Conclusion] We demonstrate that nSMase2/ceramide promotes high calcium and phosphate-induced VSMC calcification,suggesting that nSMase2/ceramide could participate in the progression of vascular calcification in patients with chronic kidney disease.
ABSTRACT
This study was conducted to investigate the chemical constituents in the root of Dysosma versipellis (Hance) M. Cheng. The constituents were isolated by silica gel, lichroprep RP-C18 and pharmadex LH-20 column chromatography and the IR, MS, NMR, 2D-NMR spectroscopic analysis were employed for the structural elucidation. Ten compounds were isolated from the 95% ethanol extract of Dysosma versipellis, their structures were elucidated as dysoverine D (1), dysoverine F (2), dysoverine A (3), podoverine A (4), α-peltatin (5), rutin (6), kaempferol-3-O-β-D-glucopyranoside (7), quercetin-3-O-β-D-glucopyranoside (8), kaempferol (9) and quercetin (10). Compound 2 is a new compound, and compounds 1 and 3-6 were isolated from this plant fo r the first time.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate whether high glucose-induced vascular calcification is associated with WNT signaling pathway.</p><p><b>METHODS</b>An in vitro model of human vascular smooth muscle cell (VSMC) calcification was induced by exposure of the cells to high glucose. The expressions of WNT signal molecules and bone-related proteins including Cbfa1, Osx, OCN and BMP2 were analyzed with qRT-PCR, and the cell calcification was assessed by alizarin red staining. The effect of Dkk1, a WNT signaling inhibitor, on high glucose-induced cell calcification was tested with alizarin red staining and calcium content analysis.</p><p><b>RESULTS</b>High glucose activated WNT signaling pathway in human VSMCs by up-regulating the expressions of WNT signal molecules including Wnt3a, Wnt7a, Fzd4 and Wisp1 mRNA by 1.86, 1.68, 2.1, and 2.3 folds, respectively, and by promoting the phosphorylation of β-catenin (2.70∓0.22, P<0.05), a key mediator of WNT signaling pathway. Inhibition of WNT signaling pathway by Dkk1 attenuated high glucose-induced VSMC calcification and down-regulated the expression of bone-related proteins Cbfa1, Osx, OCN, and BMP2 by (51∓9)%, (58∓11)%, (56∓10)%, and (62∓10)% (P<0.01).</p><p><b>CONCLUSION</b>WNT signaling pathway is involved in high glucose-induced VSMC calcification.</p>