Résumé
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.
Résumé
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 P<0.01). The expression levels of TLR4, TNF-α, IL-8 and p-NF-κB/p65 in HSYA group were decreased compared with that in the HP group, and p65 was decreased in nucleus and increased in cytoplasm (all P<0.05). SOD content in HSYA group was significantly higher than that in HP group, and MDA content was significantly lower than that in HP group (all P<0.01).@*Conclusions@#HSYA can reduce calcification and calcium deposition of vascular smooth muscle cells induced by high phosphorus. The mechanism is related to the inhibition of the activation of TLR4/NF-κB pathway and the inhibition of oxidative stress.