Abstract 677: The Role of Discoidin Domain Receptor 1 in Vascular Calcification in Atherosclerosis and Diabetes

2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Marsel Lino ◽  
Michelle P Bendeck
Keyword(s):  
Signaling Pathway ◽  
Vascular Calcification ◽  
Kinase Domain ◽  
Plaque Burden ◽  
Tyrosine Kinase Domain ◽  
Discoidin Domain Receptor ◽  
Related Transcription Factor ◽  
Discoidin Domain Receptor 1

Background: Atherosclerosis and diabetes share many common pathogenic mechanisms. Vascular calcification is a common and severe complication in patients with atherosclerosis and type-2 diabetes (T2D), and occurs when vascular smooth muscle cells (VSMCs) trans-differentiate into osteoblast-like cells, in a process driven by runt-related transcription factor-2 (RUNX2). Our laboratory has recently discovered that Discoidin Domain Receptor-1 (DDR1) deletion reduces vascular calcification in vivo in Ldlr -/- mice. Additionally, we have shown that RUNX2 activity is reduced in Ddr1 -/- VSMCs. However, little is known about the mechanism by which DDR1 mediates calcification and RUNX2 activity. Rationale: The insulin signaling pathway plays an important role in T2D and VSMC function. It has recently been discovered that PI3K binds to the DDR1 tyrosine kinase domain upon DDR1 activation. Hypothesis: DDR1 promotes vascular calcification by inducing RUNX2 activity via the PI3K/Akt signaling pathway in T2D. Methods/Results: To study the role of DDR1 in vascular calcification in T2D, Ldlr -/- (SKO) and Ldlr-/-; Ddr1 -/- (DKO) mice were placed on a modified Western diet (40% fat, 43% carbohydrates, 0.5% cholesterol) for 12 weeks. Oil Red-O staining of the descending aorta showed reduced plaque burden in DKO mice (9.1±2.7% vs 4.4±2.9% surface area; p<0.05). Measurements of vascular calcification are ongoing. To determine the mechanism by which DDR1 modulates VSMC calcification, primary VSMCs collected from Ddr1 +/+ and DDR1 -/- mice were cultured in osteogenic media for 12 days to induce calcification. Proliferation and calcification were significantly reduced in DDR1 -/- VSMCs. Additionally, DDR1 -/- VSMCs showed significantly reduced p-Akt levels when stimulated with insulin. Significance: Current treatments for vascular calcification are non-specific and often pose a risk to bone health. This is the first study to test the role of DDR1 in vascular calcification in an animal model of T2D, which will provide novel insight into the mechanism of vascular calcification and uncover new potential therapeutic approaches.

scholarly journals Procyanidin B2 Reduces Vascular Calcification through Inactivation of ERK1/2-RUNX2 Pathway

Antioxidants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 916
Author(s):  
Yingquan Liang ◽  
Guilan Chen ◽  
Feng Zhang ◽  
Xiaoxiao Yang ◽  
Yuanli Chen ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Vascular Calcification ◽  
Aortic Root ◽  
Smooth Muscle Actin ◽  
Bone Morphogenetic Protein 2 ◽  
Plaque Burden ◽  
Runx2 Expression ◽  
Plaque Instability ◽  
Related Transcription Factor

Vascular calcification is strongly associated with atherosclerotic plaque burden and plaque instability. The activation of extracellular signal-regulated kinase 1/2 (ERK1/2) increases runt related transcription factor 2 (RUNX2) expression to promote vascular calcification. Procyanidin B2 (PB2), a potent antioxidant, can inhibit ERK1/2 activation in human aortic smooth muscle cells (HASMCs). However, the effects and involved mechanisms of PB2 on atherosclerotic calcification remain unknown. In current study, we fed apoE-deficient (apoE−/−) mice a high-fat diet (HFD) while treating the animals with PB2 for 18 weeks. At the end of the study, we collected blood and aorta samples to determine atherosclerosis and vascular calcification. We found PB2 treatment decreased lesions in en face aorta, thoracic, and abdominal aortas by 21.4, 24.6, and 33.5%, respectively, and reduced sinus lesions in the aortic root by 17.1%. PB2 also increased α-smooth muscle actin expression and collagen content in lesion areas. In the aortic root, PB2 reduced atherosclerotic calcification areas by 75.8%. In vitro, PB2 inhibited inorganic phosphate-induced osteogenesis in HASMCs and aortic rings. Mechanistically, the expression of bone morphogenetic protein 2 and RUNX2 were markedly downregulated by PB2 treatment. Additionally, PB2 inhibited ERK1/2 phosphorylation in the aortic root plaques of apoE−/− mice and calcified HASMCs. Reciprocally, the activation of ERK1/2 phosphorylation by C2-MEK1-mut or epidermal growth factor can partially restore the PB2-inhibited RUNX2 expression or HASMC calcification. In conclusion, our study demonstrates that PB2 inhibits vascular calcification through the inactivation of the ERK1/2-RUNX2 pathway. Our study also suggests that PB2 can be a potential option for vascular calcification treatment.

scholarly journals Regulation of Jak2 Function by Phosphorylation of Tyr317 and Tyr637 during Cytokine Signaling

2009 ◽  
Vol 29 (12) ◽  
pp. 3367-3378 ◽  
Author(s):  
Scott A. Robertson ◽  
Rositsa I. Koleva ◽  
Lawrence S. Argetsinger ◽  
Christin Carter-Su ◽  
Jarrod A. Marto ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Kinase Activity ◽  
Feedback Inhibition ◽  
Dominant Role ◽  
Kinase Domain ◽  
Cytokine Signaling ◽  
Tyrosine Kinase Domain ◽  
Phosphorylation Sites ◽  
Cytokine Stimulation

ABSTRACT Jak2, the cognate tyrosine kinase for numerous cytokine receptors, undergoes multisite phosphorylation during cytokine stimulation. To understand the role of phosphorylation in Jak2 regulation, we used mass spectrometry to identify numerous Jak2 phosphorylation sites and characterize their significance for Jak2 function. Two sites outside of the tyrosine kinase domain, Tyr317 in the FERM domain and Tyr637 in the JH2 domain, exhibited strong regulation of Jak2 activity. Mutation of Tyr317 promotes increased Jak2 activity, and the phosphorylation of Tyr317 during cytokine signaling requires prior activation loop phosphorylation, which is consistent with a role for Tyr317 in the feedback inhibition of Jak2 kinase activity after receptor stimulation. Comparison to several previously identified regulatory phosphorylation sites on Jak2 revealed a dominant role for Tyr317 in the attenuation of Jak2 signaling. In contrast, mutation of Tyr637 decreased Jak2 signaling and activity and partially suppressed the activating JH2 V617F mutation, suggesting a role for Tyr637 phosphorylation in the release of JH2 domain-mediated suppression of Jak2 kinase activity during cytokine stimulation. The phosphorylation of Tyr317 and Tyr637 act in concert with other regulatory events to maintain appropriate control of Jak2 activity and cytokine signaling.

scholarly journals Inhibition of Prostate Cancer DU-145 Cells Proliferation by Anthopleura anjunae Oligopeptide (YVPGP) via PI3K/AKT/mTOR Signaling Pathway

Marine Drugs ◽  
2018 ◽  
Vol 16 (9) ◽  
pp. 325 ◽  
Author(s):  
Xiaojuan Li ◽  
Yunping Tang ◽  
Fangmiao Yu ◽  
Yu Sun ◽  
Fangfang Huang ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Signaling Pathway ◽  
Caspase 3 ◽  
Mtor Signaling ◽  
Mtor Signaling Pathway ◽  
Nude Mouse Model ◽  
Dose Dependent

We investigated the antitumor mechanism of Anthopleura anjunae oligopeptide (AAP-H, YVPGP) in prostate cancer DU-145 cells in vitro and in vivo. Results indicated that AAP-H was nontoxic and exhibited antitumor activities. Cell cycle analysis indicated that AAP-H may arrest DU-145 cells in the S phase. The role of the phosphatidylinositol 3-kinase/protein kinase B/mammalian rapamycin target protein (PI3K/AKT/mTOR) signaling pathway in the antitumor mechanism of APP-H was investigated. Results showed that AAP-H treatment led to dose-dependent reduction in the levels of p-AKT (Ser473), p-PI3K (p85), and p-mTOR (Ser2448), whereas t-AKT and t-PI3K levels remained unaltered compared to the untreated DU-145 cells. Inhibition of PI3K/AKT/mTOR signaling pathway in the DU-145 cells by employing inhibitor LY294002 (10 μM) or rapamycin (20 nM) effectively attenuated AAP-H-induced phosphorylation of AKT and mTOR. At the same time, inhibitor addition further elevated AAP-H-induced cleaved-caspase-3 levels. Furthermore, the effect of AAP-H on tumor growth and the role of the PI3K/AKT/mTOR signaling pathway in nude mouse model were also investigated. Immunohistochemical analysis showed that activated AKT, PI3K, and mTOR levels were reduced in DU-145 xenografts. Western blotting showed that AAP-H treatment resulted in dose-dependent reduction in p-AKT (Ser473), p-PI3K (p85), and p-mTOR (Ser2448) levels, whereas t-AKT and t-PI3K levels remained unaltered. Similarly, Bcl-xL levels decreased, whereas that of Bax increased after AAP-H treatment. AAP-H also increased initiator (caspase 8 and 9) and executor caspase (caspase 3 and 7) levels. Therefore, the antitumor mechanism of APP-H on DU-145 cells may involve regulation of the PI3K/AKT/mTOR signaling pathway, which eventually promotes apoptosis via mitochondrial and death receptor pathways. Thus, the hydrophobic oligopeptide (YVPGP) can be developed as an adjuvant for the prevention or treatment of prostate cancer in the future.

scholarly journals Has-miR-875-5p Inhibits Tumorigenesis by Targeting USF2 via TGF-β Signaling Pathway in Gastric Cancer

2021 ◽  
Author(s):  
Shenshuo Gao ◽  
Zhikai Zhang ◽  
Xubin Wang ◽  
Yan Ma ◽  
Chensheng Li ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Signaling Pathway ◽  
Research Direction ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Gastric Cancer Cells ◽  
New Research

Abstract Background: Gastric cancer (GC) is one of the most common malignancies, and more and more evdiences show that the pathogenesis is regulated by various miRNAs.In this study, we investigated the role of miR-875 in GC. Methods:The expression of miR-875-5p was detected in human GC specimens and cell lines by miRNA RT-PCR. The effect of miR-875-5p on GC proliferation was determined by CCK-8 proliferation assay and EDU assay. Migration and invasion were examined by transwell migration and invasion assay and wound healing assay. The interaction between miR-875-5p and its target gene USF2 was verified by a dual luciferase reporter assay. The effects of miR-875-5p in vivo were studied in xenograft nude mice models.Related proteins were detected by Western blot.Results:The results showed that miR-875-5p inhibited the proliferation, migration and invasion of gastric cancer cells in vitro, and inhibited tumorigenesis in vivo. USF2 proved to be a direct target of miR-875-5p. Knockdown of USF2 partially counteracts the effects of miR-875-5p inhibitors.Overexpression of miR-875-5p can inhibit proliferation, migration, and invasion through the TGF-β signaling pathway by down-regulation of USF2 in GC, providing a new research direction for the diagnosis and targeted therapy of GC.Conclusions: MiR-875-5pcan inhibited the progression of GC by directly targeting USF2 and negatively regulating TGF-β signaling pathway.In the future, miR-875-5p is expected to be used as a potential therapeutic target for GC therapy.

scholarly journals Inhibition of Gastrin-Releasing Peptide Attenuates Phosphate-Induced Vascular Calcification

Cells ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 737 ◽  
Author(s):  
Hyun-Joo Park ◽  
Yeon Kim ◽  
Mi-Kyoung Kim ◽  
Jae Joon Hwang ◽  
Hyung Joon Kim ◽  
...  
Keyword(s):  
Vascular Calcification ◽  
Vascular System ◽  
Ex Vivo ◽  
Calcium Deposition ◽  
Gastrin Releasing Peptide ◽  
Cardiovascular Morbidity And Mortality ◽  
Potential Strategy ◽  
Grp Receptor

Vascular calcification is the pathological deposition of calcium/phosphate in the vascular system and is closely associated with cardiovascular morbidity and mortality. Here, we investigated the role of gastrin-releasing peptide (GRP) in phosphate-induced vascular calcification and its potential regulatory mechanism. We found that the silencing of GRP gene and treatment with the GRP receptor antagonist, RC-3095, attenuated the inorganic phosphate-induced calcification of vascular smooth muscle cells (VSMCs). This attenuation was caused by inhibiting phenotype change, apoptosis and matrix vesicle release in VSMCs. Moreover, the treatment with RC-3095 effectively ameliorated phosphate-induced calcium deposition in rat aortas ex vivo and aortas of chronic kidney disease in mice in vivo. Therefore, the regulation of the GRP-GRP receptor axis may be a potential strategy for treatment of diseases associated with excessive vascular calcification.

scholarly journals RANKL Is Involved in Runx2-Triggered Hepatic Infiltration of Macrophages in Mice with NAFLD Induced by a High-Fat Diet

2020 ◽  
Vol 2020 ◽  
pp. 1-8 ◽  
Author(s):  
Li Zhong ◽  
Jianghan Yuan ◽  
Lu Huang ◽  
Shan Li ◽  
Liang Deng
Keyword(s):  
High Fat Diet ◽  
Macrophage Infiltration ◽  
Macrophage Migration ◽  
High Fat ◽  
Transwell Assay ◽  
Nonalcoholic Fatty Liver ◽  
Related Transcription Factor

Background. Receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL) is significant in the activation of inflammation. Runt-related transcription factor 2 (Runx2) promotes the hepatic infiltration of macrophages in nonalcoholic fatty liver disease (NAFLD). We studied how RANKL affects Runx2-triggered macrophage infiltration in NAFLD. Method. 30 male C57BL/6J mice at 4 weeks of age were utilized in this study, 20 mice received a high-fat diet (HFD), and 10 mice received standard rodent chow over 8 months. The histopathologic features of the liver were identified by H&E, Oil red O, and Masson staining. Runx2, RANKL, and F4/80 were analyzed by western blot, real-time PCR, and immunohistochemistry in vivo, respectively. Lentivirus or siRNA was utilized for transwell assay to investigate the role of RANKL in Runx2-induced macrophage migration in vitro. Results. Compared to controls, during NAFLD development, HFD increased Runx2 and RANKL in vivo in NASH (P<0.01). Meanwhile, a correlation between the expression of Runx2 and RANKL (P<0.05) was evident. In addition, the hepatic infiltration of macrophages was increased upon HFD feeding, and analysis showed that the macrophage infiltration was correlated with the expression of Runx2 or RANKL (P<0.05). In vitro, we found that overexpression or deficiency of Runx2 increased or decreased the production of RANKL in mHSCs. Then, transwell assay revealed that RANKL was involved in Runx2-induced macrophage migration. Conclusions. Overall, RANKL is involved in Runx2-triggered macrophage migration during NAFLD pathogenesis, which may provide an underlying therapeutic target for NAFLD.

Anti-angiogenic role of microRNA-23b in melanoma by disturbing NF-κB signaling pathway via targeted inhibition of NAMPT

2020 ◽  
Vol 16 (10) ◽  
pp. 541-458 ◽  
Author(s):  
Renrong Lv ◽  
Jing Yu ◽  
Qian Sun
Keyword(s):  
Signaling Pathway ◽  
Tumor Tissues ◽  
Melanoma Treatment ◽  
Melanoma Patients ◽  
Targeted Inhibition ◽  
Nicotinamide Phosphoribosyl Transferase ◽  
Poor Patient Survival

Aim: Melanoma is the major cause of death in patients inflicting skin cancer. We identify miR-23b plays an anti-angiogenic role in melanoma. Materials & methods: We collected tumor tissues from melanoma patients. Experiments in vivo and in vitro were designed to evaluate the role of miR-23b in melanoma. Results & conclusion: miR-23b was found to be downregulated in melanoma tissues, and associated with poor patient survival. Elevating miR-23b inhibited cell viability and colony formation, reduced pro-angiogenetic ability, and accelerated apoptosis in SK-MEL-28 cells. miR-23b targeted NAMPT. Disturbing NF-κB signaling pathway with ammonium pyrrolidinedithiocarbamate (an inhibitor of NF-kB signaling pathway) impeded acquired pro-angiogenetic ability of nicotinamide phosphoribosyl transferase-overexpressed SK-MEL-28 cells. MiR-23b is a prognostic factor in melanoma. This study provides an enhanced understanding of microRNA-based targets for melanoma treatment.

Induction of resistance to the Abelson inhibitor STI571 in human leukemic cells through gene amplification

Blood ◽  
2000 ◽  
Vol 95 (5) ◽  
pp. 1758-1766 ◽  
Author(s):  
Philipp le Coutre ◽  
Elena Tassi ◽  
Marileila Varella-Garcia ◽  
Rossella Barni ◽  
Luca Mologni ◽  
...  
Keyword(s):  
Cell Line ◽  
Gene Amplification ◽  
Marker Chromosome ◽  
Kinase Domain ◽  
Leukemic Cells ◽  
Tyrosine Kinase Domain ◽  
Fish Analysis ◽  
Human Leukemic Cells

The 2-phenylaminopyrimidine derivative STI571 has been shown to selectively inhibit the tyrosine kinase domain of the oncogenicbcr/abl fusion protein. The activity of this inhibitor has been demonstrated so far both in vitro with bcr/abl expressing cells derived from leukemic patients, and in vivo on nude mice inoculated with bcr/abl positive cells. Yet, no information is available on whether leukemic cells can develop resistance to bcr/ablinhibition. The human bcr/abl expressing cell line LAMA84 was cultured with increasing concentrations of STI571. After approximately 6 months of culture, a new cell line was obtained and named LAMA84R. This newly selected cell line showed an IC50 for the STI571 (1.0 μM) 10-fold higher than the IC50 (0.1 μM) of the parental sensitive cell line. Treatment with STI571 was shown to increase both the early and late apoptotic fraction in LAMA84 but not in LAMA84R. The induction of apoptosis in LAMA84 was associated with the activation of caspase 3–like activity, which did not develop in the resistant LAMA84R cell line. LAMA84R cells showed increased levels of bcr/abl protein and mRNA when compared to LAMA84 cells. FISH analysis with BCR- and ABL-specific probes in LAMA84R cells revealed the presence of a marker chromosome containing approximately 13 to 14 copies of the BCR/ABL gene. Thus, overexpression of the Bcr/Abl protein mediated through gene amplification is associated with and probably determines resistance of human leukemic cells to STI571 in vitro.

Sign in / Sign up

Export Citation Format

Share Document