scholarly journals Melatonin attenuates vascular calcification by activating mitochondrial fusion and mitophagy via an AMPK/OPA1 signaling pathway

2019 ◽  
Author(s):  
chenweiren chen ◽  
jia qi yang ◽  
fang liu ◽  
xue qin shen ◽  
yuan sha

Abstract Background: Mitochondrial fusion/mitophagy play a role in cardiovascular calcification. Melatonin has been shown to protect against cardiovascular disease. This study sought to explore whether melatonin attenuates vascular calcification by regulating mitochondrial fusion/mitophagy via an AMP activated protein kinase/ Optic atrophy 1 (AMPK/OPA1) signaling pathway.Methods: The effects of melatonin on vascular calcification were investigated in vascular smooth muscle cells (VSMCs). Calcium deposits were visualised by Alizarin red staining. Calcium content and alkaline phosphatase (ALP) activity were used to evaluate osteogenic differentiation. Western blots were used to measure expression of runt-related transcription factor 2 (Runx2), mitofusin 2 (Mfn2), mito-light chain 3 II (LC3II) and cleaved caspase3. Results: Melatonin markedly reduced calcium deposition and ALP activity. Runx2 and cleaved caspase3 were found to be down-regulated and Mfn2 or mito-LC3II was found to be enhanced in response to melatonin, together with a decrease in mitochondrial superoxide levels. Melatonin also maintained mitochondrial function and promoted mitochondrial fusion/mitophagy via OPA1 pathway. But OPA1 deletion abolished the protective effects of melatonin on VSMC calcification. Melatonin treatment significantly increased the p-AMPK and OPA1 protein expression. Treatment with compound C ablated the benefit observed with melatonin treatment. Conclusions: Melatonin protects VSMC against calcification by promoting mitochondrial fusion/mitophagy via AMPK/OPA1 pathway.

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Shuangshuang Wang ◽  
Maoqing Tong ◽  
Siwang Hu ◽  
Xiaomin Chen

Background. Vascular calcification, which is associated with low-level chronic inflammation, is a complication that occurs during aging, atherosclerosis, chronic kidney disease, diabetes mellitus, and hyperlipaemia. In this study, we used conditioned media from mesenchymal stem cells (MSC-CM), a source of autologous cytokines, to test the hypothesis that MSC-CM inhibits vascular smooth muscle cell (VSMC) calcification by suppressing inflammation and apoptosis. Methods. VSMCs were treated with β-glycerophosphate (β-GP) to induce calcification and MSC-CM was used as a treatment. Calcium deposition was evaluated using alizarin red and von Kossa staining after a 7-day induction period. Intracellular calcium contents were measured via the o-cresolphthalein complexone method, and alkaline phosphatase (ALP) activity was determined using the para-nitrophenyl phosphate method. The expressions of specific-osteogenic markers, inflammatory cytokines, and apoptosis-associated genes/proteins were examined by real-time polymerase chain reaction or western blotting. Results. MSC-CM inhibited β-GP-induced calcium deposition in VSMCs and decreased intracellular calcium content and ALP activity. Additionally, MSC-CM suppressed the β-GP-induced increases in BMP2, Msx2, Runx2, and osteocalcin expression. Additionally, MSC-CM decreased the expression of TNF-α, IL-1β, and IL-6 in VSMC. MSC-CM also partly blocked β-GP-induced VSMC apoptosis, which was associated with an increase in the Bcl-2/Bax expression ratio and a decrease in caspase-3 expression. Conclusion. Our study results suggest that MSC-CM can inhibit VSMC calcification. This suggests a potential novel clinical application for MSCs in the treatment of vascular calcification and associated diseases.


2020 ◽  
Vol 2020 ◽  
pp. 1-23 ◽  
Author(s):  
Wei Ren Chen ◽  
Yu Jie Zhou ◽  
Jia Qi Yang ◽  
Fang Liu ◽  
Xue Ping Wu ◽  
...  

Mitochondrial fusion/mitophagy plays a role in cardiovascular calcification. Melatonin has been shown to protect against cardiovascular disease. This study sought to explore whether melatonin attenuates vascular calcification by regulating mitochondrial fusion/mitophagy via the AMP-activated protein kinase/optic atrophy 1 (AMPK/OPA1) signaling pathway. The effects of melatonin on vascular calcification were investigated in vascular smooth muscle cells (VSMCs). Calcium deposits were visualized by Alizarin Red S staining, while calcium content and alkaline phosphatase (ALP) activity were used to evaluate osteogenic differentiation. Western blots were used to measure expression of runt-related transcription factor 2 (Runx2), mitofusin 2 (Mfn2), mito-light chain 3 (mito-LC3) II, and cleaved caspase 3. Melatonin markedly reduced calcium deposition and ALP activity. Runx2 and cleaved caspase 3 were downregulated in response to melatonin, whereas Mfn2 and mito-LC3II were enhanced and accompanied by decreased mitochondrial superoxide levels. Melatonin also maintained mitochondrial function and promoted mitochondrial fusion/mitophagy via the OPA1 pathway. However, OPA1 deletion abolished the protective effects of melatonin on VSMC calcification. Melatonin treatment significantly increased p-AMPK and OPA1 protein expression, whereas treatment with compound C ablated the observed benefits of melatonin treatment. Collectively, our results demonstrate that melatonin protects VSMCs against calcification by promoting mitochondrial fusion/mitophagy via the AMPK/OPA1 pathway.


2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Jin-Rui Chang ◽  
Yue-Long Hou ◽  
Wei-Wei Lu ◽  
Jin-Sheng Zhang ◽  
Yan-Rong Yu ◽  
...  

Vascular calcification (VC) is highly associated with increased morbidity and mortality in patients with advanced chronic kidney disease(CKD). We previously reported that paracrine/autocrine factor intermedin (IMD) could protect against VC. In the present study we assessed the hypothesis that IMD inhibits VC by upregulating klotho protein. VC in CKD rat was induced by 5/6 nephrectomy plus vitamin D 3 administration and vascular smooth muscle cells (VSMCs) calcification was induced by calcifying media containing β -glycerophosphate and CaCl 2 . IMD (100 ng kg -1 h -1 ) was systemically administered by a mini-osmotic pump. CKD rat aortas showed lower IMD content and increased expression of its receptors (calcitonin receptor-like receptor,CRLR/receptor activity-modifying protein 3, RAMP3), along with increased aortic alkaline phosphatase (ALP) activity and calcium deposition. In vivo administration of IMD significantly reduced aortic ALP activity and calcium deposition in CKD rats when compared with vehicle treatment, which was further confirmed in cultured VSMCs. Concurrently, the loss of smooth muscle lineage markers and klotho protein in aortas was rescued by administering IMD to CKD rats with VC. However, the inhibitory effects of IMD on VC were abolished upon pre-treatment with small interfering RNA to reduce klotho. Moreover, the increased effects of IMD on klotho were abolished upon pretreatment with small interfering RNA to reduce its receptors or with PKA inhibitor H89. These results demonstrated that IMD attenuates VC by upregulating klotho via CRLR/RAMP3-cAMP/PKA signaling pathway in rat with CKD. IMD is an important paracrine/autocrine protective factor for VC.


2017 ◽  
Vol 42 (6) ◽  
pp. 2391-2403 ◽  
Author(s):  
Yi-Xuan Chen ◽  
Dao-Yu Zhu ◽  
Zheng-Liang Xu ◽  
Jun-Hui Yin ◽  
Xiao-Wei Yu ◽  
...  

Background: Alcohol abuse is known to be a leading risk factor for atraumatic osteonecrosis of the femoral head (ONFH), in which the suppression of osteogenesis plays a critical role. Cordycepin benefits bone metabolism; however, there has been no study to determine its effect on osteonecrosis. Methods: Human bone mesenchymal stem cells (hBMSCs) were identified by multi-lineage differentiation. Alkaline phosphatase (ALP) activity, RT-PCR, western blots, immunofluorescent assay and Alizarin red staining of BMSCs were evaluated. A rat model of alcohol-induced ONFH was established to investigate the protective role of cordycepin against ethanol. Hematoxylin & eosin (H&E) staining and micro-computerized tomography (micro-CT) were performed to observe ONFH. Apoptosis was assessed by TdT-mediated dUTP nick end labeling (TUNEL). Immunohistochemical staining was carried out to detect OCN and COL1. Results: Ethanol significantly suppressed ALP activity, decreased gene expression of OCN and BMP2, lowered levels of RUNX2 protein, and reduced immunofluorescence staining of OCN and COL1 and calcium formation of hBMSCs. However, these inhibitory effects were attenuated by cordycepin co-treatment at concentrations of 1 and 10 µg/mL Moreover, it was revealed that the osteo-protective effect of cordycepin was associated with modulation of the Wnt/β-catenin pathway. In vivo, by micro-CT, TUNEL and immunohistochemical staining of OCN and COL1, we found that cordycepin administration prevented alcohol-induced ONFH. Conclusion: Cordycepin treatment to enhance osteogenesis may be considered a potential therapeutic approach to prevent the development of alcohol-induced ONFH.


2021 ◽  
Vol 11 ◽  
Author(s):  
Yu-qiang Pei ◽  
Yong-qiu Zheng ◽  
Yao-dong Ding ◽  
Qi-xiang Xu ◽  
Di Cao ◽  
...  

Background: Triptolide (TP), a naturally derived compound from Tripterygium wilfordii, has been proven effective in protecting against cardiovascular system, but the molecular mechanisms underlying its protective effects are poorly understood. In the current study, we sought to test the potential protective role of TP in the regulation of vascular calcification in a rat model and explore whether TP attenuates medial vascular calcification by upregulating miRNA-204.Methods: Vitamin D3 plus nicotine (VDN) was used to induce a vascular calcification (VC) model of rat aorta. Von Kossa and Hematoxylin-Eosin staining were applied to assess the degree of calcification of rat aortas. Calcium content and alkaline phosphatase activity were measured. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) was applied to quantify miRNA-204 expression. The localization of runt-related transcription factor-2 (RUNX2) and bone morphogenetic protein-2 (BMP2) expressions were detected by immunohistochemistry and western blotting.Results: Administration of TP greatly reduced vascular calcification in a dose-dependent manner compared with VC controls. The increase in ALP activity and calcium content was ameliorated by TP. Moreover, protein expression levels of BMP2 and RUNX2 were significantly reduced in calcified aortas. MiRNA-204 expression was increased in the TP-treated groups compared with VC controls and the effects of TP were reversed by the intravenous injection of miRNA-204-interfering lentivirus. However, the miRNA-204-overexpressing lentivirus had no additional effects on ALP activity, calcium content, BMP2 and RUNX2 expressions compared with those from TP group.Conclusion: TP inhibited BMP2 and RUNX2 expression and attenuated vascular calcification via upregulating the level of miRNA-204. TP appears to be a potential new therapeutic option for treating vascular calcification.


2019 ◽  
Vol 48 (4) ◽  
pp. 030006051985164
Author(s):  
Jun Li ◽  
Youjian Peng

Objective To investigate the effects of the flavonoid, puerarin, on osteogenic differentiation of human periodontal ligament stem cells (PDLSCs). Methods Human PDLSCs were isolated from patients undergoing orthodontic treatment, and the cell surface markers CD146, CD34, CD45, and STRO-1 were identified by immunofluorescence. Cell proliferation was detected by MTT assay; alkaline phosphatase (ALP) activity was measured, and calcium deposition was detected by alizarin red staining. PCR was then used to detect the distributions of COL-I, OPN, Runx2, and OCN, genes related to osteogenic differentiation. Results Staining was positive for cytokines CD146, CD34, CD45, and STRO-1 in the experimental group; staining was also positive for silk protein, but negative for keratin. After 7 days of culture, exposure to puerarin significantly promoted the level of intracellular ALP; increased puerarin concentration led to increased intracellular ALP. Red mineralized nodules appeared upon exposure to puerarin and the number of nodules was concentration-dependent. PCR analysis revealed that COL-I, OPN, Runx2, and OCN expression levels increased as puerarin concentration increased. Conclusions Exposure to puerarin can promote proliferation and ALP activity in human PDLSCs, thus promoting both molecular and osteogenic differentiation; these findings may provide a theoretical basis for the clinical treatment of periodontal disease with puerarin.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Ana Amaya Garrido ◽  
José M Valdivielso ◽  
Stanislas Faguer ◽  
Arnaud Del Bello ◽  
Benedicte Buffin-Meyer ◽  
...  

Abstract Background and Aims Vascular calcification, leading to aortic stiffening and heart failure, is decisive risk factor for cardiovascular (CV) mortality in patients with chronic kidney disease (CKD). Promoted by bone mineral disorder and systemic inflammation in CKD patients, vascular calcification is a complex mechanism involving osteochondrogenic differentiation of vascular smooth muscle cells (VSMCs) and abnormal deposition of minerals in the vascular wall. Despite intensive research efforts in recent years, available treatments have limited effect and none of them prevent or reverse vascular calcification. The aim of this study was to analyse the serum proteome of CKD stage 3-4 patients in order to unravel new molecular changes associated to CV morbid-mortality and to decipher the role of novel candidates on vascular calcification to provide potential new therapeutic agents. Method In this study we used serum samples from two independent cohorts: 112 CKD stage 3-4 patients with a 4 years follow-up for CV events and 222 CKD stage 5 patients exhibiting a broad range of calcification degree determined by histological quantification in the epigastric and/or iliac artery. Serum proteome analysis was performed using tandem mass-spectrometry in a subcohort of 66 CKD3-4 patients and validation of protein candidates was performed using ELISA in the two full cohorts. Human primary vascular smooth muscle cells and mouse aortic rings were used for calcification assays. Calcium content was quantified using QuantiChrom calcium assay kit and calcium deposition was visualized by Alizarin Red and Von Kossa staining. Results Among 443 proteins detected in the serum of CKD3-4 patients, 134 displayed significant modified abundance in patients with CV events (n=32) compared to patients without (n=34). One of the most prominent changes was increased level of calprotectin (up to 8.6 fold, P<.0001). Using ELISA, we validated that higher serum calprotectin levels were strongly associated with higher probability of developing CV complications and increased mortality in CKD stage 3-4 patients (Figure A). Moreover, we showed that higher serum calprotectin was associated with increased vascular calcification levels in CKD stage 5 patients (Figure B). In vitro, calprotectin promoted calcification of human VSMCs (p<0.0001) (Figures C-D) and in mouse aortic rings (p<0.0001) (Figure E-F). Interestingly, these effects were significantly attenuated by paquinimod, a calprotectin inhibitor (Figures C-F). Conclusion Circulating calprotectin is a novel predictor of CV outcome and mortality in CKD patients. Calprotectin also shows calcification-inducing properties and its blockade by paquinimod alleviates its effects. Future experiments will consist in deciphering the signalling pathways involved in the regulation of calcification by calprotectin and evaluating in vivo the therapeutic potential of paquinimod on the development of medial vascular calcification lesions associated with CKD.


2021 ◽  
Author(s):  
Ebrahim Rahmani-Moghadam ◽  
Tahereh Talaei-Khozani ◽  
Vahideh Zarrin ◽  
Zahra Vojdani

Abstract Background: Hydroxyapatite (HA) can be loaded by some osteogenic inducing agents such as thymoquinone (TQ) and alginate. This study was performed to investigate the effect of TQ loading into HA/alginate scaffolds on osteogenic differentiation capability of mesenchymal stem cells.Methods: HA scaffolds were fabricated by casting and sintering method and impregnated by TQ containing alginate. The stem cells were loaded onto the scaffolds and induced to differentiate into osteoblasts. Alkaline Phosphatase (ALP) activity, Alizarin Red S, Real-Time qRT-PCR, and MTT assessments were done. Finally, the cells were examined with a light microscope, confocal microscope, and SEM.Results: The results showed that the presence of the alginate decelerates the degradation rate and reinforces the mechanical strength. while the presence of TQ had no significant influence on physical and mechanical properties of the HA/alginate scaffolds, it led to a significant increase in ALP activity and expression of collagen, osteopontin, and osteocalcin at early phase of differentiation. Also, TQ administration had no impact on calcium deposition and proliferation as well as bone-marker expression at long term differentiation.Conclusion: TQ accelerates the differentiation of the stem cells into the osteoblasts without changing the properties of the scaffolds, and the HA/alginate/TQ scaffold can be used as a scaffold with osteogenic properties in bone tissue engineering applications.


Author(s):  
Liu Yang ◽  
Rongbo Dai ◽  
Hao Wu ◽  
Zeyu Cai ◽  
Nan Xie ◽  
...  

Background: Vascular calcification is a prevalent complication in chronic kidney disease and contributes to increased cardiovascular morbidity and mortality. XBP1 (X-box binding protein 1), existing as the unspliced (XBP1u) and spliced (XBP1s) forms, is a key component of the endoplasmic reticulum stress involved in vascular diseases. However, whether XBP1u participates in the development of vascular calcification remains unclear. Methods: We aim to investigate the role of XBP1u in vascular calcification.XBP1u protein levels were reduced in high phosphate (Pi)-induced calcified vascular smooth muscle cells (VSMCs), calcified aortas from mice with adenine diet-induced chronic renal failure (CRF) and calcified radial arteries from CRF patients. Results: Inhibition of XBP1u rather than XBP1s upregulated in the expression of the osteogenic markers runt-related transcription factor 2 (Runx2) and msh homeobox2 (Msx2), and exacerbated high Pi-induced VSMC calcification, as verified by calcium deposition and Alizarin red S staining. In contrast, XBP1u overexpression in high Pi-induced VSMCs significantly inhibited osteogenic differentiation and calcification. Consistently, SMC-specific XBP1 deficiency in mice markedly aggravated the adenine diet- and 5/6 nephrectomy-induced vascular calcification compared with that in the control littermates. Further interactome analysis revealed that XBP1u bound directly to β-catenin, a key regulator of vascular calcification, via aa 205-230 in its C-terminal degradation domain. XBP1u interacted with β-catenin to promote its ubiquitin-proteasomal degradation and thus inhibited β-catenin/T-cell factor (TCF)-mediated Runx2 and Msx2 transcription. Knockdown of β-catenin abolished the effect of XBP1u deficiency on VSMC calcification, suggesting a β-catenin-mediated mechanism. Moreover, the degradation of β-catenin promoted by XBP1u was independent of glycogen synthase kinase 3β (GSK-3β)-involved destruction complex. Conclusions: Our study identified XBP1u as a novel endogenous inhibitor of vascular calcification by counteracting β-catenin and promoting its ubiquitin-proteasomal degradation, which represents a new regulatory pathway of β-catenin and a promising target for vascular calcification treatment.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Rita Bou Assaf ◽  
Mohammad Fayyad-Kazan ◽  
Fatima Al-Nemer ◽  
Rawan Makki ◽  
Hussein Fayyad-Kazan ◽  
...  

Background. Novel treatments for bone defects, particularly in patients with poor regenerative capacity, are based on bone tissue engineering strategies which include mesenchymal stem cells (MSCs), bioactive factors, and convenient scaffold supports. Objective. In this study, we aimed at comparing the potential for different scaffolds to induce osteogenic differentiation of human maxillary Schneiderian sinus membrane- (hMSSM-) derived cells. Methods. hMSSM-derived cells were seeded on gelatin, collagen, or Hydroxyapatite β-Tricalcium phosphate-Fibrin (Haβ-TCP-Fibrin) scaffolds. Cell viability was determined using an MTT assay. Alizarin red staining method, Alkaline phosphatase (ALP) activity assay, and quantitative real-time PCR analysis were performed to assess hMSSM-derived cells osteogenic differentiation. Results. Cell viability, calcium deposition, ALP activity, and osteoblastic markers transcription levels were most striking in gelatin scaffold-embedded hMSSM-derived cells. Conclusion. Our findings suggest a promising potential for gelatin-hMSSM-derived cell construct for treating bone defects.


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