Medial arterial calcification (MAC) accompanying chronic kidney disease (CKD) leads to increased vessel wall stiffness, myocardial ischemia, heart failure, and increased cardiovascular morbidity and mortality. Unfortunately, there are currently no drugs available to treat MAC. The natural polyphenol epigallocatechin-3-gallate (EGCG) has been demonstrated to protect against cardiovascular disease; however, whether EGCG supplementation inhibits MAC in CKD remains unclear. In this study, we utilize a CKD-associated MAC model to investigate the effects of EGCG on vascular calcification and elucidate the underlying mechanisms involved. Our findings demonstrate that EGCG treatment significantly reduces calcium phosphate deposition and osteogenic differentiation of VSMCs
Objective To explore the effect of Fas/FasL pathway on fluoride.induced apoptosis in hurnan neumbla8toma SH-SY5Y cells.Methods The cell survival rate,percentage of apoptosis,and mRNA expression levels of Fas and FasL were measured respectively after the SH-SY5Y cells were exposed to O(control),20,40,80 mg/L sodium nuoride(NaF)for 24 hours/n vitro.Furthermore,the changes of the percentage of apoptosis and mRNA expression levels of Fas and FasL in 40 mg/L NaF-treated groups incubated with activaling or neutralizing anti-Fas antibody(CH11 or ZB4)also observed respectively.Results Compared with the control group(100.00%), the cell surval rates in 40,80 mg/L NaF-treated groups[(84.63±2.57)%,(69.04±5.63)%]were significandy lower(P<0.01).The percentage of apoptosis in 40,80 mg/L NaF.treated groups[(8.54±1.95)%.(17.94±2.71)%]were higher(P<0.05)than thal in the control group[(3.32±1.33)%],and increased with the dose of NaF.NaF could up-regulate Fas and FasL mRNA expression,and increased the Fas/β-actin [40 ms/L group (0.94±0.51),80 mg/L group(0.99±0.12)]and FasL/β-actin[40 mg/L group(0.96±0.42),80 mg/L group(0.99±0.24)] ratio,compared with the control[Eas/β-actin(0.50±0.33),FasL/β-actin(0.58±0.23)],both the difference had 8tatistical significances (P<0.05).NaF and CH I 1 had a synergisfic effect on apoptosis and mRNA expression levels of Fas and FasLL(F=32.89,18.46,.14.69,P<0.01)while NaF and ZB4 had an antagonistic effect (F=5.73,24.26,10.17,P<0.05 or<0.01).Conclusion NaF exposure can cause apoptosis in SH-Y5Y cells,and the Fas/FasL pmhway may play an important role in NaF-induced apoptosis.
Key words:
Fluorides; Neuroblastoma; Apoptosis; Fas; FasL
Abstract Backgrounds Vascular calcification often occurs with osteoporosis, a contradictory association known as “the calcification paradox”. Osteoblast-derived matrix vesicles (Ost-MVs) have been implicated in bone mineralization, and also have a potential role in ectopic vascular calcification. Herein, we aim to investigate the contributions that Ost-MVs make to the bone–vascular calcification paradox and the underlying mechanisms. Methods and Results Hyperlipidemia-induced atherosclerotic calcification in mice was accompanied with bone mineral loss, as evidenced by reduced deposition of Ost-MVs in the bone matrix and increased release of Ost-MVs into the circulation. Intravenous injection of fluorescent DiІ-labeled Ost-MVs revealed a marked fluorescence accumulation in the aorta of atherogenic mice, whereas no fluorescence signals were observed in normal controls. Using proteomics to analyze proteins in non-matrix bound Ost-MVs and mineralized SMC-derived MVs (SMC-MVs), we found Lamp1 was specifically expressed in SMC-MVs, and Nid2 was exclusively expressed in Ost-MVs. We further demonstrated that both Lamp1 and Nid2 were co-localized with Collagen І within calcific plaques, indicating the involvement of both Ost-MVs and SMC-MVs in atherosclerotic calcification. Mechanistically, LPS-induced vascular injury facilitated the transendothelial transport of Ost-MVs. The recruitment of circulating Ost-MVs was regulated by remodeled Collagen І during calcification progression. Furthermore, the phenotypic transition of SMCs determined the endocytosis of Ost-MVs. Finally, we demonstrated that either recruited Ost-MVs or resident SMC-MVs accelerated atherosclerotic calcification, depending on the Ras-Raf-ERK signaling. Conclusion Atherosclerotic calcification-induced Ost-MVs are released into circulation, facilitating the transport from bone to plaque lesions and exacerbating artery calcification progression. The mechanisms of Ost-MVs recruitment include vascular injury allowing transendothelial transport of Ost-MVs, collagen І remodeling promoting Ost-MVs aggregation, and SMC phenotypic switch to facilitate Ost-MVs uptake. Our results further revealed that both recruited Ost-MVs and calcifying SMC-MVs aggravate calcification through the Ras-Raf-ERK pathway.
Abstract Aims Identifying novel mediators of lethal myocardial reperfusion injury that can be targeted during primary percutaneous coronary intervention (PPCI) is key to limiting the progression of patients with ST-elevation myocardial infarction (STEMI) to heart failure. Here, we show through parallel clinical and integrative preclinical studies the significance of the protease cathepsin-L on cardiac function during reperfusion injury. Methods and results We found that direct cardiac release of cathepsin-L in STEMI patients (n = 76) immediately post-PPCI leads to elevated serum cathepsin-L levels and that serum levels of cathepsin-L in the first 24 h post-reperfusion are associated with reduced cardiac contractile function and increased infarct size. Preclinical studies demonstrate that inhibition of cathepsin-L release following reperfusion injury with CAA0225 reduces infarct size and improves cardiac contractile function by limiting abnormal cardiomyocyte calcium handling and apoptosis. Conclusion Our findings suggest that cathepsin-L is a novel therapeutic target that could be exploited clinically to counteract the deleterious effects of acute reperfusion injury after an acute STEMI.
Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) are important recalcitrant halogenated compounds that have been regarded as major environmental pollutants. Recently, their concurrent appearance in the environment and humans and their structural and toxicological profile similarities have sparked interest in the potential toxicologic consequences of their coexposure. The aim of the current study was to evaluate the cytogenotoxic effects induced by 2,2',4,4'-tetrabromodiphenyl ether (PBDE-47) combined with 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153) treatment in human neuroblastoma cells (SH-SY5Y) in vitro. SH-SY5Y cells were exposed to different concentrations of PBDE-47 (0, 2, 4, 8 μM) with or without PCB153 (5 μM) for 24 h. Thereafter, the cell viability, DNA damage, chromosomal abnormalities, and DNA-protein crosslinks (DPC) were determined. The results show that PBDE-47 and PCB153 alone and in combination induce DNA damage, with an increase in the frequency of micronuclei (MN) and DPC formation with increasing PBDE-47 concentration. In cells coexposed to PBDE-47 and PCB153, the cell viability significantly decreased while the MN frequency, DNA damage and DPC formation were all obviously increased compared to those of cells treated with the corresponding concentrations of PBDE-47 or PCB153 alone. Factorial analysis suggests that there were interactions between PBDE-47 and PCB153. The results imply that PBDE-47 interacts with PCB153 to inhibit cell viability and induce DNA damage, DPC formation, and chromosome abnormalities.
Myocardial infarction (MI) is a leading cause of heart failure and death worldwide. Preservation of contractile function and protection against adverse changes in ventricular architecture (cardiac remodeling) are key factors to limiting progression of this condition to heart failure. Consequently, new therapeutic targets are urgently required to achieve this aim. Expression of the Runx1 transcription factor is increased in adult cardiomyocytes after MI; however, the functional role of Runx1 in the heart is unknown.
To investigate the effects of 2, 2', 4,4 '-polybrominated diphenyl ethers (PBDE-47) on SH-SY5Y cells were oxidative stress and DNA damage in human neuroblastoma cells (SH-SY5Y cells).cultured in DMEM supplemented with 10% fetal bovine serum at 37 degrees C in a humidified incubator with 95% air and 5% CO2. The rate of cellular survivors, LDH leakage, contents of MDA and GSH, activity of SOD, and DNA damage were measured after exponentially growing cells were incubated with 1, 2, 4, 6, 8 and 10 microg/ml PBDE-47 for 24 hours in vitro.The rate of cellular survivors in the low dose PBDE-47-treated groups (l microg/ml and 2 microg/ml) were higher than the control group (P <0.05), but those in the high dose PBDE-47-treated groups (4, 6, 8 and 10 microg/ml) were significantly lower than the control group (P < 0.05). Compared with the control group, the GSH content were significantly decreased (P < 0.05) and DNA tail moment were significantly increased with increasing PBDE-47 concentrations. The MDA content in the high PBDE-treated groups (4, 8 and 10 microg/ml) were notably higher than the control group and increased with increasing PBDE-47 concentrations (P < 0.05). In the high PBDE-treated groups (4, 6, 8 and l0 microg/ml), the LDH leakage were markedly higher and the SOD activity were markedly lower than the control group (P < 0.05). The percentage of DNA in the tail in the high PBDE-treated groups (6,8 and 10 microg/ml) were visibly higher than the control group (P < 0.05).PBDE-47 could induce oxidative stress and DNA damage in SH-SY5Y cells. The oxidative stress may play an important role in the DNA damage induced by PBDE-47.