1. Mechanism of hydroxysafflower yellow A in the regulation of vascular smooth muscle cell calcification
Yiran HAN ; Tianhua XU ; Xiaobo QIU ; Zitong SHENG ; Pengzhi WAN ; Yue LI ; Li YAO
Chinese Journal of Nephrology 2019;35(11):848-855
Objective:
To investigate the role and mechanism of Hydroxysafflor yellow A (HSYA) in the calcification of vascular smooth muscle cells (VSMC) induced by β-glycerol phosphate (β-GP).
Methods:
VSMC were cultured with 10% fetal bovine serum+1% double anti-high glucose DMEM medium at 37℃ and 5%CO2 incubator, and were subcultured according to cell growth density at 1∶4 ratio. The cells were divided into three groups: control group (NC), high-phosphate-induced calcification (HP) group, and HSYA intervention (HSYA) group. The Calcium deposition amount was measured by alizarin red staining and calcium determination kit. The expressions of ALP, RUNX2, RANKL, α-SMA and inflammation indicators TLR4, TNF-α, IL-8 were detected by Western blotting method; Western blotting was also used to detect calcification index alkaline phosphatase (ALP) and Runt-related transcription factor 2 (RUNX2). Nuclear factor kappa B receptor activating factor ligand(RANKL), α-smooth muscle actin (α-SMA), and the expressions of TLR4/NF-κB pathway and inflammatory response-related indicators Toll-like receptor 4 (TLR4), interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-α). The nuclear protein and cytoplasmic proteins were respectively extracted. The expressions of p65 in nucleus and cytoplasm, as well as the expressions of p65 and phosphorylated p65 in total proteins were detected by Western blotting method. Superoxide dismutase (SOD) and malondialdehyde (MDA) kit were used to detect the content of antioxidant enzymes and oxidation end products in cells.
Results:
Western blotting showed that the expressions of ALP, RUNX2 and RANKL in HSYA group were significantly lower than that in HP group. The expression of α-SMA was increased than that of HP group (all
2.Mechanism of Sclerostin/Lrp4 in the regulation of vascular smooth muscle cell calcification
Jian WANG ; Xiaobo QIU ; Zitong SHENG ; Tianhua XU ; Yinke DU ; Lining WANG ; Li YAO
Chinese Journal of Nephrology 2018;34(3):208-213
Objective To investigate the possible mechanism of sclerostin/Lrp4 in calcification of VSMC induced by high phosphorus and the protective effect of Ginkgo biloba extract.Methods Aortic vascular smooth muscle cells (VSMCs) of SD rats were extracted and identified.VSMCs were divided into normal control group,high phosphorus induced calcification group (10 mmol/L β-glycerophosphate+50 μg/ml ascorbic acid),and high phosphorus induced calcification+Ginkgo biloba extract intervention group (10 mmol/L β-glycerophosphate+50 μg/ml ascorbic acid+0.5 mg/ml GBE),cultured in different mediums for 14 days.Vonkossa staining and alizarin red staining were used to detect the calcification of VSMCs.The mRNA level of BGP was detected by real time PCR,and the protein expressions of sclerostin and Lrp4 were detected by Western blot.Results Compared with normal control group,vonkossa staining and alizarin red staining showed significant calcium deposition in calcification group.Compared with calcification group,calcium salt deposition was significantly reduced in GBE treatment group.Real time PCR results showed β-catenin and BGP mRNA expressions in VSMC calcification group were higher than those in normal control group (P< 0.05).mRNA expressions of β-catenin and BGP in GBE treatment group were lower than those in calcification group (all P < 0.05).Compared with normal control group,the protein expression of sclerostin was increased,but the protein expression of Lrp4 was decreased in calcified group (all P < 0.05).Compared with calcification group,the protein expression of sclerostin decreased and the protein expression of Lrp4 increased in GBE treatment group (all P < 0.05).Conclusions High phosphorus can induce VSMC calcification by activating Wn/β-catenin signaling pathway.Sclerostin/Lrp4 is involved in hyperphosphine-induced VSMC calcification.GBE can reduce the high phosphorus induced VSMC calcification by regulating the Wnt/β-catenin signaling pathway.
3.Cordyceps sinensis alleviates β-glycerophosphate-induced vascular smooth muscle call calcification through promoting autophagy
Xiaobo QIU ; Zitong SHENG ; Yiran HAN ; Tianhua XU ; Binyao TIAN ; Fei ZHAO ; Yanqiu YU ; Li YAO
Chinese Journal of Nephrology 2019;35(2):119-126
Objective To investigate the influence mechanism of Cordyceps sinensis (CS) on β-glycerophosphate-induced vascular smooth muscle cell (VSMC) calcification.Methods The effect of CS on VSMC cell viability was detected by CCK-8.The cellular models of rat VSMC calcification were established by treating with β-glycerophosphate (β-GP,10 mmol/L);then CS (10 mg/L),autophagy inhibitor 3-methyladenine (3-MA,5 mmol/L),and AMPK inhibitor compound C (CC,10 μmol/L) were added to the cell cultures.There were a total of 5 experiment groups:VSMC cultured in normal medium (Control),VSMC treated with β-GP,VSMC treated with β-GP and CS,VSMC treated with 3-MA,β-GP and CS,and VSMC treated with CC,β-GP and CS.The calcium nodules and calcium content were examined with alizarin red S staining and the O-cresolphthaleincomplexone method,respectively.The autophagosomes within the VSMC were observed using transmission electron microscope (TEM).Immunofluorescence showed the accumulation of microtubule-associated protein 1 light chain 3 (LC3) puncta.In addition,levels of osteogenic related proteins,autophagy related proteins,and AMPK/mTOR pathway related proteins were evaluated by Western blotting.Results CS increased the number of autophagosomes and the accumulation of LC3 puncta within VSMC.It also upregulated the protein levels of LC3 Ⅱ/LC3 Ⅰ,beclin1,α-SMA,and p-AMPK;whereas,the protein levels of Runx2 and p-mTOR,as well as calcium nodules and calcium content were reduced (all P < 0.01).When the cells were pretreated with 3-MA before treating with β-GP and CS,the autophagosomes,accumulation of LC3 puncta,and protein levels of LC3 Ⅱ/LC3 Ⅰ,beclinl,and α-SMA were decreased (all P < 0.01);however,the protein level of Runx2,and the calcium nodules and calcium content were increased (all P < 0.01).Nevertheless,when the cells were pretreated with CC before giving β-GP and CS,the autophagosomes,the accumulation of LC3 puncta,and the expression levels of p-AMPK,LC3 Ⅱ/LC3 Ⅰ,beclin1,and α-SMA were significantly down-regulated (all P < 0.01);whereas,the expression levels of Runx2 and p-mTOR,as well as calcium nodules and calcium content were increased (all P < 0.01).Conclusions CS can effectively alleviate β-GP-induced VSMC calcification,which may be due to the activation of autophagy by AMPK/mTOR signaling pathway.