Abstract 640: Overexpression of Vasohibin-2 Exacerbates Development of Angiotensin II-Induced Thoracic Aortic Aneurysms Independent of VeEGF

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Michihiro Okuyama ◽  
Haruhito A Uchida ◽  
Ryoko Umebayashi ◽  
Yuki Kakio ◽  
Hidemi Takeuchi ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Protein Expression ◽  
Aortic Arch ◽  
Gelatin Zymography ◽  
Annexin V ◽  
Aortic Aneurysms ◽  
Tunel Staining ◽  
Significant Difference

Objective: Chronic angiotensin II (AngII) infusion promotes both thoracic (TAAs) and abdominal aortic aneurysms (AAAs) in mice. Vasohibin-2 (VASH2) is known to cause angiogenesis at the sprouting front of neovascularization. The purpose of this study was to examine whether VASH2 influenced AngII-induced TAAs. Methods: Male C57BL/6J mice (10-week-old) were injected with VASH2 or LacZ expressing adenovirus (Ad; 7.5 x 10 9 vp/100 μL) via tail vein at 2 week intervals. One week after the first injection, subcutaneous infusion of either AngII (1,000 ng/kg/min) or saline by mini osmotic pumps was started for 3 weeks. Consequently, mice were divided into 4 groups: AngII + Ad VASH2 (n=22), AngII + Ad LacZ (n=21), saline + Ad VASH2 (n=10), saline + Ad LacZ (n=8). Next, in order to examine whether VASH2 affected TAAs via VEGF regulation, bevacizumab was intraperitoneally administrated into mice; AngII + Ad VASH2 + saline (n=15), AngII + Ad VASH2 + bevacizumab (n=15). TAAs were evaluated in all mice by en face method. Third, human aortic smooth muscle cells (hSMCs) were infected with Ad VASH2 or Ad LacZ, stimulated with or without AngII to evaluate further mechanism. Result: Intima area of aortic arch was significantly larger in AngII + Ad VASH2 group than in AngII + Ad LacZ group (19.78 ± 0.40 mm 3 vs 17.74 ± 0.44 mm 3 , P < 0.001). Gelatin zymography demonstrated that AngII upregulated latent MMP-2 expression, and activated MMP-2 most prominently in AngII + VASH2 group. Protein expression of p21 and p53 in thoracic aortas was enhanced in AngII + VASH2 group. Positive TUNEL staining was observed in thoracic aortic wall of AngII + VASH2 group. No significant difference in intima area of aortic arch between AngII + Ad VASH2 + saline group and AngII + Ad VASH2 + bevacizumab group. In vitro, the same results were observed regarding protein expression of p21 and p53, and TUNEL staining. In addition, Annexin-V staining was detected only in AngII + VASH2 group. Conclusion: Overexpression of VASH2 accelerated development of AngII-induced TAAs in vivo. VASH2-induced cell apoptosis may influence AngII-induced TAA formation independent of VEGF.

Lipopolysaccharide induces apoptosis in adult rat ventricular myocytes via cardiac AT1 receptors

2002 ◽  
Vol 283 (2) ◽  
pp. H461-H467 ◽  
Author(s):  
Hai Ling Li ◽  
Jun Suzuki ◽  
Evelyn Bayna ◽  
Fu-Min Zhang ◽  
Erminia Dalle Molle ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Ventricular Myocytes ◽  
Annexin V ◽  
Left Ventricular ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Rat Ventricular Myocytes ◽  
Adult Rat ◽  
Cardiac Apoptosis

Lipopolysaccharide (LPS) from gram-negative bacteria circulates in acute, subacute, and chronic conditions. It was hypothesized that LPS directly induces cardiac apoptosis. In adult rat ventricular myocytes (isolated with depyrogenated digestive enzymes to minimize tolerance), LPS (10 ng/ml) decreased the ratio of Bcl-2 to Bax at 12 h; increased caspase-3 activity at 16 h; and increased annexin V, propidium iodide, and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling staining at 24 h. Apoptosis was blocked by the caspase inhibitor benzyloxycarbonyl-valine-alanine-aspartate fluoromethylketone (Z-VAD-fmk), captopril, and angiotensin II type 1 receptor (AT1) inhibitor (losartan), but not by inhibitors of AT2 receptors (PD-123319), tumor necrosis factor-α (TNFRII:Fc), or nitric oxide ( N G-monomethyl-l-arginine). Angiotensin II (100 nmol/l) induced apoptosis similar to LPS without additive effects. LPS in vivo (1 mg/kg iv) increased apoptosis in left ventricular myocytes for 1–3 days, which dissipated after 1–2 wk. Losartan (23 mg · kg−1 · day−1 in drinking water for 3 days) blocked LPS-induced in vivo apoptosis. In conclusion, low levels of LPS induce cardiac apoptosis in vitro and in vivo by activating AT1 receptors in myocytes.

scholarly journals COX-2 mediates angiotensin II-induced (pro)renin receptor expression in the rat renal medulla

2014 ◽  
Vol 307 (1) ◽  
pp. F25-F32 ◽  
Author(s):  
Fei Wang ◽  
Xiaohan Lu ◽  
Kexin Peng ◽  
Li Zhou ◽  
Chunling Li ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Protein Expression ◽  
Renal Medulla ◽  
Receptor Expression ◽  
Ang Ii ◽  
Cox 2 ◽  
Renin Content

(Pro)renin receptor (PRR) is predominantly expressed in the distal nephron where it is activated by angiotensin II (ANG II), resulting in increased renin activity in the renal medulla thereby amplifying the de novo generation and action of local ANG II. The goal of the present study was to test the role of cycloxygenase-2 (COX-2) in meditating ANG II-induced PRR expression in the renal medulla in vitro and in vivo. Exposure of primary rat inner medullary collecting duct cells to ANG II induced sequential increases in COX-2 and PRR protein expression. When the cells were pretreated with a COX-2 inhibitor NS-398, ANG II-induced upregulation of PRR protein expression was almost completely abolished, in parallel with the changes in medium active renin content. The inhibitory effect of NS-398 on the PRR expression was reversed by adding exogenous PGE2. A 14-day ANG II infusion elevated renal medullary PRR expression and active and total renin content in parallel with increased urinary renin, all of which were remarkably suppressed by the COX-2 inhibitor celecoxib. In contrast, plasma and renal cortical active and total renin content were suppressed by ANG II treatment, an effect that was unaffected by COX-2 inhibition. Systolic blood pressure was elevated with ANG II infusion, which was attenuated by the COX-2 inhibition. Overall, the results obtained from in vitro and in vivo studies established a crucial role of COX-2 in mediating upregulation of renal medullary PRR expression and renin content during ANG II hypertension.

scholarly journals Effect of Doxycycline on Survival in Abdominal Aortic Aneurysms in a Mouse Model

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Lisa C. Adams ◽  
Julia Brangsch ◽  
Jan O. Kaufmann ◽  
Dilyana B. Mangarova ◽  
Jana Moeckel ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Ex Vivo ◽  
Endothelial Damage ◽  
Aortic Aneurysms ◽  
Clinical Dose ◽  
Doxycycline Treatment ◽  
Abdominal Aortic ◽  
Significant Difference ◽  
Aneurysm Growth

Background. Currently, there is no reliable nonsurgical treatment for abdominal aortic aneurysm (AAA). This study, therefore, investigates if doxycycline reduces AAA growth and the number of rupture-related deaths in a murine ApoE−/− model of AAA and whether gadofosveset trisodium-based MRI differs between animals with and without doxycycline treatment. Methods. Nine ApoE−/− mice were implanted with osmotic minipumps continuously releasing angiotensin II and treated with doxycycline (30 mg/kg/d) in parallel. After four weeks, MRI was performed at 3T with a clinical dose of the albumin-binding probe gadofosveset (0.03 mmol/kg). Results were compared with previously published wild-type control animals and with previously studied ApoE−/− animals without doxycycline treatment. Differences in mortality were also investigated between these groups. Results. In a previous study, we found that approximately 25% of angiotensin II-infused ApoE−/− mice died, whereas in the present study, only one out of 9 angiotensin II-infused and doxycycline-treated ApoE−/− mice (11.1%) died within 4 weeks. Furthermore, doxycycline-treated ApoE−/− mice showed significantly lower contrast-to-noise (CNR) values ( p = 0.017 ) in MRI compared to ApoE−/− mice without doxycycline treatment. In vivo measurements of relative signal enhancement (CNR) correlated significantly with ex vivo measurements of albumin staining (R2 = 0.58). In addition, a strong visual colocalization of albumin-positive areas in the fluorescence albumin staining with gadolinium distribution in LA-ICP-MS was shown. However, no significant difference in aneurysm size was observed after doxycycline treatment. Conclusion. The present experimental in vivo study suggests that doxycycline treatment may reduce rupture-related deaths in AAA by slowing endothelial damage without reversing aneurysm growth.

Survivin Is Required for Proliferation, but Not Polyploidization of Megakaryocytes.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1328-1328
Author(s):  
Jeremy Q Wen ◽  
Cindy Leung ◽  
Zan Huang ◽  
Sara Small ◽  
John Crispino
Keyword(s):  
Bone Marrow ◽  
Ex Vivo ◽  
Survivin Expression ◽  
Annexin V ◽  
Retroviral Infection ◽  
Hematopoietic Stem ◽  
Significant Difference ◽  
Megakaryocyte Progenitors

Abstract Survivin is a member of chromosome passenger complex, which plays an important role in chromosome alignment, separation and cytokinesis. We recently reported that survivin is necessary for the proliferation and survival of hematopoietic stem and progenitor cells. Furthermore, we previously showed that reduced levels of survivin expression facilitates megakaryocyte development, whereas elevated levels of survivin inhibit their maturation and polyploidization. However, the extent to which survivin is necessary for polyploidization and terminal differentiation of committed megakaryocytes remains unclear. To determine whether survivin is required for megakaryocyte and platelet biogenesis, we mated mice with floxed alleles of survivin (sur fl/fl) to mice that express Cre recombinase under the control of the PF4 promoter. Compound mutant animals appeared grossly normal and harbored normal platelet counts. Furthermore, survivin deleted and control littermates displayed similar expression of CD41 and CD42, as well as similar DNA content within the CD41+ population. The only significant difference detected was an increase in annexin V staining of CD41+ cells within the bone marrow of the mice with survivin deletion. Analysis of DNA extracted from these bone marrows showed no evidence of the survivin deletion, indicating that the surviving cells all escaped excision. These in vivo findings are consistent with a requirement for survivin in the survival or proliferation of megakaryocyte progenitors. Next, to induce megakaryocyte development ex vivo, we cultured bone marrow from surv fl/fl mice in vitro in the presence of TPO. Using this approach, we were able to induce survivin deletion in 75% of the cells as evidenced by PCR. Despite the deletion of survivin, polyploidization of the ex vivo generated megakaryocytes was unaffected. Finally, we induced deletion of survivin by retroviral infection of surv fl/fl progenitors with MSCV-Cre and found that megakaryocyte polyploidization was actually increased in the excised population. Taken together, our results suggest that survivin is not required for polyploidization, but is necessary for proliferation of megakaryocyte progenitors.

Abstract 244: Vascular Induction of Adam17 in vitro and in Vivo By Angiotensin Ii: Potential Involvement of a Hypoxia Responsible Element

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Takehiko Takayanagi ◽  
Allison M Bourne ◽  
Tomonori Kobayashi ◽  
Nariaki Yanagawa ◽  
Akira Takaguri ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Protein Expression ◽  
Cardiovascular System ◽  
Promoter Activation ◽  
Feed Forward ◽  
Feed Forward Loop ◽  
Fold Induction ◽  
Enzymatic Activation

ADAM17 has been shown to play critical roles in angiotensin II (AngII)-dependent as well as independent types of pathophysiological vascular remodeling in vitro and in vivo. Enzymatic activation of ADAM17 by AngII has been described, however, little is known regarding regulation of ADAM17 protein expression in the cardiovascular system. Here we test our hypothesis that AngII induces ADAM17 protein expression to originate a feed forward loop of ADAM17 activation/induction in the vasculature. 8 week old control mice were infused with 1000 ng/kg/min AngII for 2 weeks via osmotic minipump. Serum starved rat VSMCs were stimulated with 100 nM AngII. ADAM17 expression was evaluated by immunohistochemistry and immunoblotting, respectively. In AngII-infused mice, marked ADAM17 induction was seen in vasculatures in heart and kidney, and carotid arteries and aortae. In VSMCs, AngII as well as PDGF-BB (50 ng/mL) time-dependently induced ADAM17 expression up to 24 hours (AngII 24h: 2.34±0.25 fold induction). Both AngII and PDGF-BB also stimulated ADAM17 promoter activity in VSMCs (AngII 24h: 2.90±0.17 fold induction). The ADAM17 promoter contains 6 typical hypoxia responsible elements (HREs). By using deletion and mutation constructs, the PDGF-BB response seems to require HRE4 located between -991 to -410 of the promoter. AngII-induced promoter activation was also lost in the HRE4 mutant. Moreover, both AngII and PDGF-BB stimulated HIF-1alpha protein expression in VSMCs at 4-8 hours. From these data, we conclude that AngII and PDGF induce ADAM17 expression in VSMCs via HIF1alpha/HRE-dependent transcriptional upregulation. The induction of ADAM17 via the HIF1/HRE-dependent mechanism likely promotes a feed-forward loop of ADAM17 activation/induction under a variety of pathophysiological conditions including hypoxia/ischemia leading to end organ damages in the cardiovascular system.

Effects of the proteasome inhibitor PS-341 on tumor growth in HTLV-1 Tax transgenic mice and Tax tumor transplants

Blood ◽  
2004 ◽  
Vol 104 (3) ◽  
pp. 802-809 ◽  
Author(s):  
Shibani Mitra-Kaushik ◽  
John C. Harding ◽  
Jay L. Hess ◽  
Lee Ratner
Keyword(s):  
Transgenic Mice ◽  
Tumor Growth ◽  
Annexin V ◽  
Tunel Staining ◽  
Nuclear Factor ◽  
Γ Irradiation ◽  
Human T Cell ◽  
Rag 1

AbstractRecent studies have shown that the transcription factor nuclear factor κB (NF-κB) regulates critical survival pathways in a variety of cancers, including human T-cell leukemia/lymphotrophic virus 1 (HTLV-1)–transformed CD4 T cells. The activation of NF-κB is controlled by proteasome-mediated degradation of the inhibitor of nuclear factor κBα (IκBα). We investigated the effects of PS-341, a peptide boronate inhibitor of the proteasome in HTLV-1 Tax transgenic tumors in vitro and in vivo. In Tax transgenic mice, PS-341 administered thrice weekly inhibited tumor-associated NF-κB activity. Quantitation of proliferation, apoptosis, and interleukin 6 (IL-6) and IL-10 secretion by tumor cells in culture revealed that the effects of PS-341 on cell growth largely correlated with inhibition of pathways mediated by NF-κB. However, the effect of PS-341 on the growth of tumors in Tax transgenic mice revealed heterogeneity in drug responsiveness. The tumor tissues treated with PS-341 show no consistent inhibition of NFκB activation in vivo. Annexin V staining indicated that PS-341 response in vivo correlated with sensitivity to apoptosis induced by γ irradiation. On the other hand, transplanted Tax tumors in Rag-1 mice showed consistent inhibition of tumor growth and prolonged survival in response to the same drug regimen. TUNEL staining indicated that PS-341 treatment sensitizes Tax tumors to DNA fragmentation.

Cardiac fibrogenesis in magnesium deficiency: a role for circulating angiotensin II and aldosterone

2006 ◽  
Vol 291 (1) ◽  
pp. H436-H440 ◽  
Author(s):  
S. Sapna ◽  
S. K. Ranjith ◽  
K. Shivakumar
Keyword(s):  
Angiotensin Ii ◽  
Magnesium Deficiency ◽  
Cardiac Fibroblasts ◽  
Control Diet ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Serum Factors ◽  
Significant Difference

Mechanisms underlying cardiac fibrogenesis in magnesium deficiency are unclear. It was reported earlier from this laboratory that serum from magnesium-deficient rats has a more pronounced stimulatory effect on cell proliferation, net collagen production, and superoxide generation in adult rat cardiac fibroblasts than serum from rats on the control diet. The profibrotic serum factors were, however, not identified. This study tested the hypothesis that circulating angiotensin II may modulate cardiac fibroblast activity in hypomagnesemic rats. Male Sprague-Dawley rats were pair-fed a magnesium-deficient (0.0008% Mg) or -sufficient (0.05%) diet for 6 days, and the effects of serum from these rats on [3H]thymidine and [3H]proline incorporation into cardiac fibroblasts from young adult rats were evaluated in the presence of losartan, an angiotensin II type 1 (AT1) receptor antagonist, and spironolactone, an aldosterone antagonist. Losartan and spironolactone markedly attenuated the stimulatory effects in vitro of serum from the magnesium-deficient and control groups, but the inhibitory effects were considerably higher in cells exposed to serum from magnesium-deficient animals. Circulating and cardiac tissue levels of angiotensin II were significantly elevated in magnesium-deficient animals (67.6% and 93.1%, respectively, vs. control). Plasma renin activity was 61.9% higher in magnesium-deficient rats, but serum angiotensin-converting enzyme activity was comparable in the two groups. Furthermore, preliminary experiments in vivo using enalapril supported a role for angiotensin II in magnesium deficiency. There was no significant difference between the groups in serum aldosterone levels. The findings suggest that circulating angiotensin II and aldosterone may stimulate fibroblast activity and contribute to a fibrogenic response in the heart in magnesium deficiency.

Targeting Matrix Metalloproteinases in Atherosclerosis and Cardiovascular Dysfunction

2019 ◽  
Vol 70 (2) ◽  
pp. 718-720
Author(s):  
Lucia Corina Dima-Cozma ◽  
Sebastian Cozma ◽  
Delia Hinganu ◽  
Cristina Mihaela Ghiciuc ◽  
Florin Mitu
Keyword(s):  
Smooth Muscle ◽  
Matrix Metalloproteinases ◽  
Cholesterol Synthesis ◽  
Balloon Dilation ◽  
Aortic Aneurysms ◽  
Arterial Lesions ◽  
Smooth Muscle Cell Migration ◽  
And Migration

Matrix metalloproteinases (MMPs) are the primary mediators of extracellular remodeling and their properties are useful in diagnostic evaluation and treatment. They are zinc-dependent proteases. MMPs have been involved in the mechanisms of atherosclerosis in various arterial areas, ischemic heart disease and myocardial infarction, atrial fibrillation and aortic aneurysms. Recently, MMP9 has been implicated in dyslipidemia and cholesterol synthesis by the liver. Increased MMP expression and activity has been associated with neointimal arterial lesions and migration of smooth muscle cells after arterial balloon dilation, while MMP inhibition decreases smooth muscle cell migration in vivo and in vitro.

The Anti-tumor Activity and Mechanisms of rLj-RGD3 on Human Laryngeal Squamous Carcinoma Hep2 Cells

2020 ◽  
Vol 19 (17) ◽  
pp. 2108-2119
Author(s):  
Yang Jin ◽  
Li Lv ◽  
Shu-Xiang Ning ◽  
Ji-Hong Wang ◽  
Rong Xiao
Keyword(s):  
Wound Healing ◽  
Western Blot ◽  
Morphological Changes ◽  
In Vivo Studies ◽  
Migration And Invasion ◽  
Tunel Staining ◽  
Dna Ladder ◽  
Western Blot Assay

Background: Laryngeal Squamous Cell Carcinoma (LSCC) is a malignant epithelial tumor with poor prognosis and its incidence rate increased recently. rLj-RGD3, a recombinant protein cloned from the buccal gland of Lampetra japonica, contains three RGD motifs that could bind to integrins on the tumor cells. Methods: MTT assay was used to detect the inhibitory rate of viability. Giemsa’s staining assay was used to observe the morphological changes of cells. Hoechst 33258 and TUNEL staining assay, DNA ladder assay were used to examine the apoptotic. Western blot assay was applied to detect the change of the integrin signal pathway. Wound-healing assay, migration, and invasion assay were used to detect the mobility of Hep2 cells. H&E staining assay was used to show the arrangement of the Hep2 cells in the solid tumor tissues. Results: In the present study, rLj-RGD3 was shown to inhibit the viability of LSCC Hep2 cells in vitro by inducing apoptosis with an IC50 of 1.23µM. Western blot showed that the apoptosis of Hep2 cells induced by rLj- RGD3 was dependent on the integrin-FAK-Akt pathway. Wound healing, transwells, and western blot assays in vitro showed that rLj-RGD3 suppressed the migration and invasion of Hep2 cells by integrin-FAKpaxillin/ PLC pathway which could also affect the cytoskeleton arrangement in Hep2 cells. In in vivo studies, rLj-RGD3 inhibited the growth, tumor volume, and weight, as well as disturbed the tissue structure of the solid tumors in xenograft models of BALB/c nude mice without reducing their body weights. Conclusion: hese results suggested that rLj-RGD3 is an effective and safe suppressor on the growth and metastasis of LSCC Hep2 cells from both in vitro and in vivo experiments. rLj-RGD3 might be expected to become a novel anti-tumor drug to treat LSCC patients in the near future.

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