scholarly journals Activation of CD137 Signaling Enhances Vascular Calcification through c-Jun N-Terminal Kinase-Dependent Disruption of Autophagic Flux

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Rui Chen ◽  
Yao Xu ◽  
Wei Zhong ◽  
Bo Li ◽  
Ping Yang ◽  
...  
Keyword(s):  
Western Blot ◽  
Vascular Calcification ◽  
Underlying Mechanism ◽  
Calcium Deposition ◽  
Control Group ◽  
Autophagic Flux ◽  
Autophagy Flux ◽  
Alp Activity

Background. Vascular calcification is widespread and clinically significant, contributing to substantial morbidity and mortality. Calcifying vascular cells are partly derived from local vascular smooth muscle cells (VSMCs), which can undergo chondrogenic or osteogenic differentiation under inflammatory environment. Recently, we have found activation of CD137 signaling accelerated vascular calcification. However, the underlying mechanism remains unknown. This study aims to identify key mediators involved in CD137 signaling-induced vascular calcification in vivo and in vitro. Methods. Autophagy flux was measured through mRFP-GFP-LC3 adenovirus and transmission electron microscopy. Von Kossa assay and alkaline phosphatase (ALP) activity were used to observe calcification in vivo and in vitro, respectively. Autophagosome-containing vesicles were collected and identified by flow cytometry and Western blot. Autophagy or calcification-associated targets were measured by Western blot, quantitative real-time PCR, and immunohistochemistry. Results. Treatment with the agonist-CD137 displayed c-Jun N-terminal kinase- (JNK-) dependent increase in the expression of various markers of autophagy and the number of autophagosomes relative to the control group. Autophagy flux experiments suggested that agonist-CD137 blocked the fusion of autophagosomes with lysosomes in cultured VSMCs. Calcium deposition, ALP activity, and the expression of calcification-associated proteins also increased in agonist-CD137 group compared with anti-CD137 group, which could be recovered by autophagy stimulator rapamycin. Autophagosome-containing vesicles collected from agonist-CD137 VSMCs supernatant promoted VSMC calcification. Conclusion. The present study identified a new pathway in which CD137 promotes VSMC calcification through the activation of JNK signaling, subsequently leading to the disruption of autophagic flux, which is responsible for CD137-induced acceleration of vascular calcification.

scholarly journals Nano-Hydroxyapatite Accelerates Vascular Calcification by Inhibiting Lysosomal Acidification in Smooth Muscle Cells.

2021 ◽  
Author(s):  
Qi Liu ◽  
Yi Luo ◽  
Yun Zhao ◽  
Pingping Xiang ◽  
Jinyun Zhu ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Calcification ◽  
Chemical Properties ◽  
Muscle Cells ◽  
Calcium Deposition ◽  
Rapid Progression ◽  
Autophagic Flux

Abstract Background: Vascular calcification (VC) is a common characteristic of aging, diabetes, chronic renal failure, and atherosclerosis. The basic component of VC is hydroxyapatite (HAp). Nano-sized HAp (nHAp) has been identified as the initiator of pathological calcification of vasculature. However, whether nHAp can induce calcification in vivo and the mechanism of nHAp in the progression of VC remains unclear.Results: We discovered that nHAp existed both in vascular smooth muscle cells (VSMCs) and their extracellular matrix (ECM) in the calcified arteries from patients. Synthetic nHAp had similar morphological and chemical properties as natural nHAp recovered from calcified artery. nHAp induced rapid progression of VC by stimulating osteogenic differentiation and accelerating mineralization of VSMCs in vitro. Synthetic nHAp could also directly induce VC in vivo. Mechanistically, nHAp was internalized into lysosome, which impaired lysosome vacuolar H+-ATPase for its acidification, therefore blocked autophagic flux in VSMCs. The accumulated autophagosomes and autolysosomes were converted into calcium-containing exosomes which were secreted into ECM and accelerated vascular calcium deposit. Inhibition of exosome release in VSMCs decreased calcium deposition. Conclusions: Our results illustrated a novel mechanism of nHAp-induced vascular calcification. Understanding the role of nHAp in autophagy-lysosome-exosome pathway in SMCs could have great clinical significance in preventing the progression of VC.

scholarly journals Amitriptyline interferes with autophagy-mediated clearance of protein aggregates via inhibiting autophagosome maturation in neuronal cells

2020 ◽  
Vol 11 (10) ◽  
Author(s):  
Yoonjung Kwon ◽  
Yeojin Bang ◽  
Soung-Hee Moon ◽  
Aeri Kim ◽  
Hyun Jin Choi
Keyword(s):  
Neurodegenerative Diseases ◽  
Depressive Disorders ◽  
Neuronal Cells ◽  
Protein Aggregates ◽  
Underlying Mechanism ◽  
Tricyclic Antidepressant ◽  
Autophagic Flux ◽  
Autophagosome Maturation

Abstract Amitriptyline is a tricyclic antidepressant commonly prescribed for major depressive disorders, as well as depressive symptoms associated with various neurological disorders. A possible correlation between the use of tricyclic antidepressants and the occurrence of Parkinson’s disease has been reported, but its underlying mechanism remains unknown. The accumulation of misfolded protein aggregates has been suggested to cause cellular toxicity and has been implicated in the common pathogenesis of neurodegenerative diseases. Here, we examined the effect of amitriptyline on protein clearance and its relevant mechanisms in neuronal cells. Amitriptyline exacerbated the accumulation of abnormal aggregates in both in vitro neuronal cells and in vivo mice brain by interfering with the (1) formation of aggresome-like aggregates and (2) autophagy-mediated clearance of aggregates. Amitriptyline upregulated LC3B-II, but LC3B-II levels did not increase further in the presence of NH4Cl, which suggests that amitriptyline inhibited autophagic flux rather than autophagy induction. Amitriptyline interfered with the fusion of autophagosome and lysosome through the activation of PI3K/Akt/mTOR pathway and Beclin 1 acetylation, and regulated lysosome positioning by increasing the interaction between proteins Arl8, SKIP, and kinesin. To the best of our knowledge, we are the first to demonstrate that amitriptyline interferes with autophagic flux by regulating the autophagosome maturation during autophagy in neuronal cells. The present study could provide neurobiological clue for the possible correlation between the amitriptyline use and the risk of developing neurodegenerative diseases.

scholarly journals ROR2 induces cell apoptosis via activating IRE1α/JNK/CHOP pathway in high-grade serous ovarian carcinoma in vitro and in vivo

2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Rui Li ◽  
Tianfeng Liu ◽  
Juanjuan Shi ◽  
Wenqing Luan ◽  
Xuan Wei ◽  
...  
Keyword(s):  
Ovarian Carcinoma ◽  
Cell Apoptosis ◽  
Underlying Mechanism ◽  
Control Group ◽  
Sequencing Analysis ◽  
High Grade ◽  
Serous Ovarian Carcinoma ◽  
Induce Cell Apoptosis

Abstract Background Epithelial ovarian cancer (EOC) is the most lethal cancer in female genital tumors. New disease markers and novel therapeutic strategies are urgent to identify considering the current status of treatment. Receptor tyrosine kinases family plays critical roles in embryo development and disease progression. However, ambivalent research conclusions of ROR2 make its role in tumor confused and the underlying mechanism is far from being understood. In this study, we sought to clarify the effects of ROR2 on high-grade serous ovarian carcinoma (HGSOC) cells and reveal the mechanism. Methods Immunohistochemistry assay and western-blot assay were used to detect proteins expression. ROR2 overexpression adenovirus and Lentivirus were used to create ROR2 overexpression model in vitro and in vivo, respectively. MTT assay, colony formation assay and transwell assay were used to measure the proliferation, invasion and migration ability of cancer cells. Flow cytometry assay was used to detect cell apoptosis rate. Whole transcriptome analysis was used to explore the differentially expressed genes between ROR2 overexpression group and negative control group. SiRNA targeted IRE1α was used to knockdown IRE1α. Kira6 was used to inhibit phosphorylation of IRE1α. Results Expression of ROR2 was significantly lower in HGSOC tissues compared to normal fallopian tube epithelium or ovarian surface epithelium tissues. In HGSOC cohort, patients with advanced stages or positive lymph nodes were prone to express lower ROR2. Overexpression of ROR2 could repress the proliferation of HGSOC cells and induce cell apoptosis. RNA sequencing analysis indicated that ROR2 overexpression could induce unfold protein response. The results were also confirmed by upregulation of BIP and phosphorylated IRE1α. Furthermore, pro-death factors like CHOP, phosphorylated JNK and phosphorylated c-Jun were also upregulated. IRE1α knockdown or Kira6 treatment could reverse the apoptosis induced by ROR2 overexpression. Finally, tumor xenograft experiment showed ROR2 overexpression could significantly repress the growth rate and volume of transplanted tumors. Conclusions Taken together, ROR2 downregulation was associated with HGSOC development and progression. ROR2 overexpression could repress cell proliferation and induce cell apoptosis in HGSOC cells. And the underlying mechanism might be the activation of IRE1α/JNK/CHOP pathway induced by ROR2.

scholarly journals FSTL1 aggravates OVA-induced allergic airway inflammation by activating NLRP3 inflammasome

2020 ◽  
Author(s):  
Yan Wang ◽  
Tian Liu ◽  
Jun-fei Wang ◽  
Bao-yi Liu ◽  
Jin-xiang Wu ◽  
...  
Keyword(s):  
Airway Inflammation ◽  
Nlrp3 Inflammasome ◽  
Allergic Airway Inflammation ◽  
Experimental Treatment ◽  
Underlying Mechanism ◽  
Whole Body ◽  
Control Group ◽  
Asthmatic Patients

Abstract Background Asthma is a common respiratory disease characterized by chronic airway inflammation. As a novel inflammatory mediator, follistatin-like protein 1 (FSTL1) can activate immune reaction, suggesting that it may contribute to inflammatory disorders such as asthma. Besides, there are growing evidences that nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) / Interleukin (IL)-1β axis participates in asthma. In this study, we investigated the role of FSTL1 in allergic airway inflammation and its underlying mechanism of activating NLRP3 inflammasome. Methods Circulating FSTL1 and IL-1β levels were quantified in serum of asthmatic patients and controls. Whole-body ablation Fstl1 heterozygous mice (Fstl1 +/- ) and control group were assessed after the experimental treatment. The effects of FSTL1 on NLRP3 inflammasome were also tested in primary macrophages of mice in vitro. Results The concentration of FSTL1 and IL-1β in serum of asthmatic patients were elevated compared with controls and were positively correlated. FSTL1 deficiency ameliorated infiltration of inflammatory cells,corresponding pathological changes,cytokine responses (IL-1β, IL-5,IL-13), mucous hypersecretion and hyper-responsiveness of airway after Ovalbumin (OVA) exposure in the mouse model. Additionally, inhibition of NLRP3 with MCC950 attenuated FSTL1-induced activation of NLRP3 inflammasome and airway inflammation in vivo and vitro. Conclusions Our data showed that FSTL1 played an important role in allergic airway inflammation by activating NLRP3 inflammasome, providing the possibility that FSTL1 could be applied as a therapeutic strategy on asthma.

scholarly journals Oroxin B Induces Apoptosis by Down-Regulating MicroRNA-221 Resulting in the Inactivation of the PTEN/PI3K/AKT Pathway in Liver Cancer

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4384 ◽  
Author(s):  
Nannan Li ◽  
Wenxiao Men ◽  
Yibo Zheng ◽  
Hechen Wang ◽  
Xiansheng Meng
Keyword(s):  
Liver Cancer ◽  
Western Blot ◽  
Microfluidic Chip ◽  
Pten Gene ◽  
Control Group ◽  
Rt Pcr ◽  
Mrna And Protein Expression ◽  
Theoretical Evidence

This study aims to investigate the anticancer effect of Oroxin B (OB) both in vitro and in vivo, and the molecular mechanism involved in microRNA-221 and the PI3K/Akt/PTEN pathway through modulation of apoptosis in Hepatocellular carcinoma (HCC). DEN-induced rats and HepG2 cells based on the microfluidic chip were employed, while the mRNA and protein expression of microRNA-221, PI3K, p-Akt and PTEN were evaluated by RT-PCR and Western blot analysis. Based on Microfluidic Chip and DENinduced rat model, OB effectively exerts anti-liver cancer effect both in vitro and in vivo, and the expression of miR-221 in OB treated groups was significantly lower than that in the control group (** p < 0.01). The RT-PCR and Western blot results suggested the PI3K mRNA and protein in OB treated groups were both lower than those in control group and indicated the overexpression of PTEN. Therefore, OB effectively exerts anticancer effects by positively regulating the PTEN gene and then inactivating the PI3K/Akt signaling pathway through down-regulating the expression of the microRNA-221, thereby inducing apoptosis of liver cancer cells. This study offers a theoretical evidence for further development and clinical guidance of OB as an anti-tumor agent.

scholarly journals Photodynamic Therapy Enhanced the Antitumor Effects of Berberine on HeLa Cells

2019 ◽  
Vol 17 (1) ◽  
pp. 413-421 ◽  
Author(s):  
Han-Qing Liu ◽  
Ya-Wen An ◽  
A-Zhen Hu ◽  
Ming-Hua Li ◽  
Guang-Hui Cui
Keyword(s):  
Photodynamic Therapy ◽  
Western Blot ◽  
Hela Cells ◽  
Mammalian Target Of Rapamycin ◽  
Control Group ◽  
Antitumor Effects ◽  
Underlying Mechanisms ◽  
And Control

AbstractIn this study we investigated the antineoplastic effects of Berberine (BBR)-mediated photodynamic therapy (PDT) on HeLa cells and its related mechanisms. The CCK-8 assay and flow cytometry were used to evaluate the proliferation and apoptosis of cells respectively. In addition, changes in protein expression levels were assessed using western blot. BBR at dose of 10 mg/kg was injected intraperitoneally to mice with tumors and PDT treatments were performed 24 hours later. In vivo imaging systems were used to evaluate the fluorescence of BBR. In vitro, PDT significantly enhanced the effects of BBR on inducing cell apoptosis and inhibiting proliferation. The in vivo results showed that the fluorescence intensity in the PDT group was decreased compared with that in the BBR group. Tumor weights and tumor size in the PDT group were less than those in the control group; however, when BBR was applied without PDT, no significant differences were observed between the BBR and control group. The results of western blot showed that PDT enhanced the inhibitory effects of BBR on the mammalian target of rapamycin (mTOR) signaling pathway, that may partly explain the potential underlying mechanisms.

The ameliorative effect of terpinen-4-ol on ER stress-induced vascular calcification depends on sirt1-mediated regulation of PERK acetylation

2021 ◽  
Author(s):  
Yan-Yan Zhang ◽  
Li He ◽  
Meng-Xin Tu ◽  
Mei Huang ◽  
Yan Chen ◽  
...  
Keyword(s):  
Er Stress ◽  
Molecular Mechanism ◽  
Vascular Calcification ◽  
Sirtuin 1 ◽  
Mass Spectrometry Analysis ◽  
Phenotypic Switching ◽  
Calcium Deposition ◽  
Acetylation Site

Abstract Background Endoplasmic reticulum (ER) stress-mediated phenotypic switching of vascular smooth muscle cells (VSMCs) is key to vascular calcification (VC) in patients with chronic kidney disease (CKD). Terpinen-4-ol exerts protective effect against cardiovascular disease, but its role and specific mechanism in VC remain unclear. We explored whether terpinen-4-ol alleviates ER stress-mediated VC through sirtuin 1 (sirt1) and elucidated its mechanism to provide evidence for its application in the clinical prevention and treatment of VC. Methods In this study, CKD-related VC animal model and β-glycerophosphate (β-GP)-induced VSMCs calcification model were established. We investigated the part of terpinen-4-ol in ER stress-induced VC in vitro and in vivo. However, in order to clarify whether terpinen-4-ol inhibits the molecular mechanism of ERs-induced VC through sirt1, we further verified the above signal transduction by knocking down sirt1 in vitro and in vivo. Results Terpinen-4-ol inhibited calcium deposition, phenotypic switching, and ER stress of VSMCs in vitro and in vivo. Furthermore, pre-incubation with terpinen-4-ol or a sirt1 agonist and transfection with lentivirus overexpressing sirt1 decreased β-GP-induced calcium salt deposition, increased sirt1 protein level, and inhibited PERK-eIF2α-ATF4 pathway activation in VSMCs, thus, alleviating VC. The opposite results were obtained in sirt1-knockdown models. Moreover, sirt1 physically interacted with and deacetylated PERK. Mass spectrometry analysis identified lysine K889 as the acetylation site of sirt1, which regulates PERK. Finally, inhibition of sirt1 reduced the effect of terpinen-4-ol on the deacetylation of PERK in vitro and in vivo and weakened the inhibitory effect of terpinen-4-ol against ER stress-mediated VC. Conclusions Terpinen-4-ol inhibits the post-transcriptional modification of PERK at the lysine K889 acetylation site by upregulating sirt1 expression level, thereby ameliorating VC by regulating ER stress. This provides evidence of the molecular mechanism of terpinen-4-ol, which supports its development as a promising therapeutic agent for CKD-VC.

Enhanced β-Catenin/Foxo1 Activity Alleviates Pulmonary Fibrosis by Inhibiting β-Catenin/T Cell Factor Signaling

2020 ◽  
Vol 10 (2) ◽  
pp. 182-188
Author(s):  
Kun Gui ◽  
Yu Huang ◽  
Meijin Wang ◽  
Jun Yang
Keyword(s):  
Extracellular Matrix ◽  
Pulmonary Fibrosis ◽  
Inflammatory Cytokines ◽  
Underlying Mechanism ◽  
Control Group ◽  
Kidney Fibrosis ◽  
Mrc5 Cell

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrosing interstitial pneumonia, resulting in chronic respiratoryfailure and eventually death. β-catenin/Foxo1 showed a protective property in kidney fibrosis, but the role of β-catenin/Foxo1 in IPF was unclear. Our study aimed to investigate the role of β-catenin/Foxo1 in IPF and explore its underlying mechanism. The IPF model was established by injection of bleomycin (BLM) in vivo and stimulation by TGF-β1 in MRC5 cell in vitro. Haematoxylin-eosin staining and Masson’s trichrome staining were performed to examine histopathological injury in lung. Protein expression of corresponding genes was detected using western blot. Immunofluorescence staining assay was carried out to detect the expression of β-catenin, Foxo1, TCF and α-SMA. The expression levels of inflammatory cytokines were determined using ELISA kit assay. The results showed that BLM induced a serious pulmonary injury and proliferated fibroblasts. A higher interaction of β-catenin with TCF and a lower interaction of β-catenin with Foxo1 was found in BLM group compared to the control group. TGF-β1 promoted β-catenin/TCF, whereas ICG-001 inhibited β-catenin/TCF, and promoted β-catenin/Foxo1. Furthermore, ICG-001 reversed TGF-β1 induced largely production of inflammatory cytokines and accumulation of extracellular matrix, as well as high expression of α-SMA. However, AS1842856, a FOXO1 antagonist, strengthened the effects induced by TGF-β1. In summary, our study revealed that β-catenin/Foxo1 protected against IPF through inhibiting inflammatory response and extracellular matrix accumulation, providing an alternative approach to explain the potential mechanism of IPF and seek for more effective therapeutic drugs.

scholarly journals The effects of insulin and liraglutide on osteoprotegerin and vascular calcification in vitro and in patients with type 2 diabetes

2015 ◽  
Vol 173 (1) ◽  
pp. 53-61 ◽  
Author(s):  
Colin Davenport ◽  
Wan A Mahmood ◽  
Hannah Forde ◽  
David T Ashley ◽  
Amar Agha ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Insulin Glargine ◽  
Vascular Calcification ◽  
Statistical Significance ◽  
Control Group ◽  
Oral Hypoglycemics ◽  
Osteogenic Gene Expression

ObjectiveVascular calcification (VC) is inhibited by the glycoprotein osteoprotegerin (OPG). It is unclear whether treatments for type 2 diabetes are capable of promoting or inhibiting VC. The present study examined the effects of insulin and liraglutide on i) the production of OPG and ii) the emergence of VC, bothin vitroin human aortic smooth muscle cells (HASMCs) andin vivoin type 2 diabetes.Design/methodsHASMCs were exposed to insulin glargine or liraglutide, after which OPG production, alkaline phosphatase (ALP) activity and levels ofRunx2,ALPand bone sialoprotein (BSP) mRNA were measured. A prospective, nonrandomised human subject study was also conducted, in which OPG levels and coronary artery calcification (CAC) were measured in a type 2 diabetes population before and 16 months after the commencement of either insulin or liraglutide treatment and in a control group that took oral hypoglycemics only.ResultsExposure to insulin glargine, but not liraglutide, was associated with significantly decreased OPG production (11 913±1409 pg/104cells vs 282±13 pg/104cells, control vs 10 nmol/l insulin,P<0.0001), increasedALPactivity (0.82±0.06 IU/104cells vs 2.40±0.16 IU/104cells, control vs 10 nmol/l insulin,P<0.0001) and increased osteogenic gene expression by HASMCs. In the clinical study (n=101), insulin treatment was associated with a significant reduction in OPG levels and, despite not achieving full statistical significance, a trend towards increased CAC in patients.ConclusionExogenous insulin down-regulated OPGin vitroandin vivoand promoted VCin vitro. Although neither insulin nor liraglutide significantly affected CAC in the present pilot study, these data support the establishment of randomised trials to investigate medications and VC in diabetes.

scholarly journals Hypoxia and its possible relationship with endometrial receptivity in adenomyosis: a preliminary study

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Song Guo ◽  
Di Zhang ◽  
Xiaowei Lu ◽  
Qian Zhang ◽  
Ruihuan Gu ◽  
...  
Keyword(s):  
Real Time ◽  
Western Blotting ◽  
Real Time Pcr ◽  
Underlying Mechanism ◽  
Endometrial Receptivity ◽  
Control Group ◽  
Expression Levels ◽  
Preliminary Study

Abstract Background Adenomyosis (AM) is an important cause of female infertility. However, the underlying mechanism remains unclear. This report describes a preliminary study of hypoxia and its possible association with endometrial receptivity in AM. Methods The study was divided into in vitro and in vivo experiments. In vitro, expression levels of the endometrial receptivity markers HOXA10 and HOXA11 in the implantation period were examined using real-time PCR and western blotting. Endometrial expression of hypoxia-inducible factor (HIF)-1α, HIF-2α, and HIF-3α was determined using immunohistochemistry. In vivo, using an AM mouse model established by oral administration of tamoxifen, we inhibited expression of HIF-2α using an HIF-2α antagonist (PT2399; 30 mg/kg body weight, twice daily by oral gavage for 2 days) and then examined expression levels of Hoxa10 and Hoxa11 using real-time PCR and western blotting. Results Endometrial mRNA and protein expression levels of HOXA10 and HOXA11 were significantly lower in patients with AM than in control patients. Expression of HIF-2α was significantly higher in the AM group than in the control group, whereas that of HIF-1α and HIF-3α was equivalent in both groups. In vivo analysis showed that administration of the HIF-2α antagonist resulted in increased expression of Hoxa10 and Hoxa11 at both the mRNA and protein levels in AM model mice. Conclusions HIF-2α overexpression may be one reason for decreased endometrial receptivity in AM. The current findings provide insight into HIF-2α-mediated AM-related infertility and suggest that PT2399 has potential as a treatment for AM. Trial registration This trial was retrospectively registered.

Sign in / Sign up

Export Citation Format

Share Document