Vascular injury response in mice is dependent on genetic background

Mouse models are employed to unravel the pathophysiology of vascular restenosis. Although much effort has been spent on how to apply an adequate arterial injury, the influence of the genetic background of mice has not yet received sufficient consideration. The study presented herein was designed to demonstrate the influence of the mouse strain on vascular injury response. Mice of a defined background (50% 129 strain and 50% DBA strain) were backcrossed into either the 129 strain or the DBA strain. Male offspring were subjected to a femoral artery injury model by applying an electric current. Morphometric analysis revealed that backcrossing into the 129 strain resulted in a significant ( P < 0.001) 17-fold increase in neointima formation ( n = 17 mice) compared with backcrossing into the DBA strain ( n = 19). The values of neointima area were 9.18 × 103 ± 2.13 × 103 and 0.54 × 103 ± 0.39 × 103 μm2, respectively. In conjunction, the vessel wall area was enhanced by 1.8-fold ( P < 0.001). In contrast, no significant differences were found for the areas of the lumen and the tunica media. Similarly, a significant increase in neointima formation was also found for mice of pure 129 strain compared with pure DBA strain. The results underline the importance of the genetic background for studies on vascular injury response. Furthermore, because the mouse genome of the various strains is well defined, serial testing of the genetic background of mice will provide candidate genes and/or genetic modifiers controlling vascular injury response.

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Vascular ligation response is independent of p107: stressing the role of the related p130

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00056.2003 ◽

2003 ◽

Vol 285 (2) ◽

pp. H915-H918 ◽

Cited By ~ 4

Author(s):

Jürgen R. Sindermann ◽

Christiane Köbbert ◽

Florian Bauer ◽

Adriane Skaletz-Rorowski ◽

Helge Hohage ◽

...

Keyword(s):

Carotid Artery ◽

Vascular Injury ◽

Femoral Artery ◽

Arterial Injury ◽

Injury Response ◽

Artery Ligation ◽

Wall Area ◽

Carotid Artery Ligation ◽

Electric Injury

Recent studies have revealed the role of the pRb family members pRb and p130 in the response to vascular injury. We evaluated the arterial injury response in the absence of p107, a protein that shares a high degree of homology with the injury-controlling p130. Carotid artery ligation and perivascular electric injury of the femoral artery were applied to p107 knockout (p107 –/–) mice, and morphometric analysis was performed 3 wk after ligation and electric injury. Arterial vessels of p107 –/– mice were indistinguishable from controls under basal conditions. After carotid artery ligation the p107 –/– mice ( n = 7) did not display an enhanced ligation response compared with controls ( n = 9), which was studied over a distance of ∼450 μm proximal and ∼200 μm distal from the ligation site, with regard to vessel wall area, neointima area, and lumen area. Corresponding with this, morphometric data obtained from the perivascular electric injury of the femoral artery confirmed the lack of enhanced ligation and injury response in the absence of p107. We conclude that the pRb family member p107 is not a key regulator in vascular injury response. These data, in conjunction with previously reported results, indicate that the control of vascular injury response is not a redundant feature of pRb proteins but primarily specific for p130. Further studies on functional domains of p130 and p107 will help to resolve the pathways in vascular injury response.

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Abstract 1172: Neointima Formation is Dependent on p38α Mitogen-Activated Protein Kinase

Circulation ◽

10.1161/circ.116.suppl_16.ii_237 ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Brandon M Proctor ◽

Anthony J Muslin

Keyword(s):

P38 Mapk ◽

Carotid Arteries ◽

Thymidine Incorporation ◽

Fold Increase ◽

Arterial Injury ◽

Mitogen Activated Protein Kinase ◽

Neointima Formation ◽

Mapk Activity ◽

Mitogen Activated Protein ◽

P38α Mapk

Neointima formation frequently occurs after arterial injury and is responsible for substantial human morbidity. We previously demonstrated that the intracellular linker protein Grb2 is required for neointima formation, and that Grb2 regulates p38α mitogen-activated protein kinase (MAPK) activation in vascular smooth muscle cells (SMCs). In this work, the role of p38α MAPK in neointima formation was examined. In vitro experiments showed that pharmacological inhibition of p38 MAPK activity in cultured SMCs blocked platelet-derived growth factor (PDGF)-stimulated DNA replication and cell proliferation. Specifically, in control SMCs, overnight stimulation with PDGF induced an 11.8-fold increase in thymidine incorporation and a 1.9 fold increase in cell number. However, inhibition of p38 MAPK activity reduced PDGF-induced thymidine incorporation to 2.8-fold (P = 0.0006) and completely blocked PDGF-stimulated cell proliferation (P = 0.0001). Also, p38 MAPK activity was required for PDGF-induced inactivation of the retinoblastoma tumor suppressor protein, Rb, and induction of mini-chromosome maintenance protein-6 (MCM6), a fundamental regulator of DNA replication. Next, compound transgenic mice were generated with doxycycline (Dox)-inducible, SMC-specific expression of a dominant-negative form of p38α MAPK (SMC-DN-p38α ). Dox induced robust expression of DN-p38α mRNA and protein in the aorta and carotid arteries of compound transgenic mice, and inactivation of native, arterial p38 MAPK. SMC-DN-p38α and single transgenic, control mice were subjected to carotid injury by use of an epoxy resin-beaded probe. After 21 days, control mice developed robust neointima formation that frequently resulted in an occlusive lesion with a mean neointima/media ratio of 2.62 (N = 8). In contrast, SMC-DN-p38α mice were resistant to the development of neointima. Specifically, neointima/media ratio was reduced to 0.63 for SMC-DN-p38α mice (N = 12; P = 0.045). In addition, compared to control mice, injured carotid arteries of SMC-DN-p38α mice showed defective p38 MAPK activation in SMCs of the tunica media. Our results demonstrate that vascular SMC p38α MAPK is required for neointima formation after arterial injury.

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Abstract 160: Tuberosis Sclerosis Complex 1 Mediated Neointima Formation and Arterial Thrombosis Following Vascular Injury

Circulation Research ◽

10.1161/res.115.suppl_1.160 ◽

2014 ◽

Vol 115 (suppl_1) ◽

Author(s):

Eo Jin Kim ◽

Yong-Joo Ahn ◽

Maya Hwewon Kim ◽

Hyung-Hwan Kim

Keyword(s):

Smooth Muscle ◽

Carotid Artery ◽

Vascular Injury ◽

Knockout Mice ◽

Arterial Thrombosis ◽

Immunoblot Analysis ◽

Arterial Injury ◽

Conditional Knockout ◽

Neointima Formation

Objectives: Vascular injury and thrombosis are main leading causes of cardiovascular diseases. Tuberous sclerosis complex (TSC) is a genetic disorder caused by heterozygous mutations in either of two genes, TSC1 and TSC2. Although role of TSCs has been implicated in cardiovascular diseases, the tissue- and isoform-specific roles of TSCs in the vascular response to injury are not known. Methods and Results: To determine the role of TSC1 in arterial injury and thrombosis, we generated vascular smooth muscle cell-specific TSC1 conditional knockout mice (TSC1SM22-/-) by crossing vascular smooth muscle cell-specific Cre (SM22Cre) mice with TSC1flox/flox mice and performed carotid artery ligation in haploinsufficient TSC1 conditional knockout mice (TSC1SM22+/-) compared with that of WT or haploinsufficient TSC2 knockout mice (TSC2+/-). Acute carotid artery occlusion was investigated by 5% ferric chloride injury. Arterial thrombosis and neointima formation were measured at 14 days after arterial ligation. Expression of proteins was observed by immunoblot analysis. The neointima formation was significantly increased in TSC1SM22+/- mice (intimal thickness/medial thickness ratio; 1.14 ± 0.14, p<0.001) compared with that of WT mice (0.13 ± 0.03). Two weeks after arterial injury, arterial thrombus area was increased in TSC1SM22+/- mice (thrombus area/luminal area ratio; 72.1 ± 4.4, p<0.001) compared with that of WT mice (0.1 ± 0.0) but there are no significant effect in acute arterial thrombosis induced by ferric chloride. Loss of TSC1 and hyper-activation of mammalian target of rapamycin complex 1 including mTOR and S6 proteins were observed by immunoblot analysis of carotid artery tissue lysates of TSC1SM22+/- mice compared with that of WT. Conclusion: These findings suggest that regulation of TSC1 and mTOR might be useful for therapeutic intervention in vascular injury and thrombosis.

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Adenosine kinase is critical for neointima formation after vascular injury by inducing aberrant DNA hypermethylation

Cardiovascular Research ◽

10.1093/cvr/cvaa040 ◽

2020 ◽

Cited By ~ 4

Author(s):

Yong Wang ◽

Yiming Xu ◽

Siyuan Yan ◽

Kaixiang Cao ◽

Xianqiu Zeng ◽

...

Keyword(s):

Smooth Muscle ◽

Vascular Injury ◽

Arterial Injury ◽

Adenosine Kinase ◽

Neointima Formation ◽

Dna Hypermethylation ◽

Vsmc Proliferation ◽

Pharmacological Inhibition ◽

Klf4 Expression ◽

Smooth Muscle Proliferation

Abstract Aims Adenosine receptors and extracellular adenosine have been demonstrated to modulate vascular smooth muscle cell (VSMC) proliferation and neointima formation. Adenosine kinase (ADK) is a major enzyme regulating intracellular adenosine levels but is function in VSMC remains unclear. Here, we investigated the role of ADK in vascular injury-induced smooth muscle proliferation and delineated the mechanisms underlying its action. Methods and results We found that ADK expression was higher in the neointima of injured vessels and in platelet-derived growth factor-treated VSMCs. Genetic and pharmacological inhibition of ADK was enough to attenuate arterial injury-induced neointima formation due to inhibition of VSMC proliferation. Mechanistically, using infinium methylation assays and bisulfite sequencing, we showed that ADK metabolized the intracellular adenosine and potentiated the transmethylation pathway, then induced the aberrant DNA hypermethylation. Pharmacological inhibition of aberrant DNA hypermethylation increased KLF4 expression and suppressed VSMC proliferation as well as the neointima formation. Importantly, in human femoral arteries, we observed increased ADK expression and DNA hypermethylation as well as decreased KLF4 expression in neointimal VSMCs of stenotic vessels suggesting that our findings in mice are relevant for human disease and may hold translational significance. Conclusion Our study unravels a novel mechanism by which ADK promotes VSMC proliferation via inducing aberrant DNA hypermethylation, thereby down-regulating KLF4 expression and promoting neointima formation. These findings advance the possibility of targeting ADK as an epigenetic modulator to combat vascular injury.

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Ovarian hormones modulate neointima formation in an animal vascular injury model through effects on neutrophil chemokine production

American Journal of Hypertension ◽

10.1016/j.amjhyper.2004.03.007 ◽

2004 ◽

Vol 17 (5) ◽

pp. S5

Author(s):

N WEATHINGTON

Keyword(s):

Vascular Injury ◽

Ovarian Hormones ◽

Neointima Formation ◽

Chemokine Production ◽

Injury Model

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The Effect of L-arginine on Neointima Formation in a Rat Vascular Injury Model

Korean Circulation Journal ◽

10.4070/kcj.1997.27.12.1350 ◽

1997 ◽

Vol 27 (12) ◽

pp. 1350

Author(s):

Doo Soo Jeon ◽

Jae Hyung Kim ◽

Ki Dong Yoo ◽

Jang Sung Chae ◽

Soon Jo Hong ◽

...

Keyword(s):

Vascular Injury ◽

Neointima Formation ◽

Injury Model

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Adenovirus-mediated Expression of a Truncated PDGFβ Receptor Inhibits Thrombosis and Neointima Formation in an Avian Arterial Injury Model

Thrombosis and Haemostasis ◽

10.1055/s-0037-1616150 ◽

2001 ◽

Vol 86 (09) ◽

pp. 914-922 ◽

Cited By ~ 10

Author(s):

Hongliu Ding ◽

Rongqing Wang ◽

Robin Marcel ◽

Daniel Fisher

Keyword(s):

Growth Factor ◽

Recombinant Adenovirus ◽

Thrombus Formation ◽

Arterial Injury ◽

Neointima Formation ◽

Injury Model ◽

Powerful Approach ◽

And Migration

SummaryPlatelet-derived growth factor (PDGF) is a major mediator of neointima formation after arterial injury. We constructed a recombinant adenovirus, Ad/PDGFtr, that expresses the soluble extracellular domain of the murine PDGFβ receptor (PDGFtr). The expressed PDGFtr was appropriately glycosylated and secreted by chicken vascular smooth muscle cells (SMCs) in vitro. The expressed PDGFtr inhibited human PDGF-BB induced receptor autophosphorylation, and also inhibited PDGF-BB induced cell proliferation without affecting PDGF-AA induced mitogenesis. In vivo transduction of balloon-injured rooster femoral arteries with Ad/PDGFtr resulted in expression and secretion of the glycosylated PDGFtr. The expressed PDGFtr significantly inhibited neointima formation compared with controls. Neointima-associated thrombus was significantly reduced in Ad/PDGFtr transduced arteries compared with controls. Thus, in addition to impacting on SMC proliferation and migration, PDGF-BB plays a role in thrombus formation in response to arterial injury. Growth factor inhibition by localized gene delivery constitutes a powerful approach to intervene in the molecular pathways involved in vascular disease.

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Nitric oxide modulates vascular inflammation and intimal hyperplasia in insulin resistance and the metabolic syndrome

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00982.2004 ◽

2005 ◽

Vol 289 (1) ◽

pp. H228-H236 ◽

Cited By ~ 37

Author(s):

Joel E. Barbato ◽

Brian S. Zuckerbraun ◽

Marcus Overhaus ◽

Kathleen G. Raman ◽

Edith Tzeng

Keyword(s):

Metabolic Syndrome ◽

Gene Transfer ◽

Vascular Injury ◽

Inflammatory Cell ◽

Ldl Receptor ◽

Receptor Expression ◽

Neointima Formation ◽

Injury Response ◽

The Metabolic Syndrome ◽

Inos Gene

Type 2 diabetes mellitus (DM) and the metabolic syndrome, both characterized by insulin resistance, are associated with an accelerated form of atherosclerotic vascular disease and poor outcomes following vascular interventions. These vascular effects are thought to stem from a heightened inflammatory environment and reduced bioavailability of nitric oxide (NO). To better understand this process, we characterized the vascular injury response in the obese Zucker rat by examining the expression of adhesion molecules, the recruitment of inflammatory cells, and the development of intimal hyperplasia. We also evaluated the ability of exogenous NO to inhibit the sequela of vascular injury in the metabolic syndrome. Obese and lean Zucker rats underwent carotid artery balloon injury. ICAM-1 and P-selectin expression were increased following injury in the obese animals compared with the lean rats. The obese rats also responded with increased macrophage infiltration of the vascular wall as well as increased neointima formation compared with their lean counterparts (intima/media = 0.91 vs. 0.52, P = 0.001). After adenovirus-mediated inducible NO synthase (iNOS) gene transfer, ICAM-1, P-selectin, inflammatory cell influx, and oxidized low-density lipoprotein (LDL) receptor expression were all markedly reduced versus injury alone. iNOS gene transfer also significantly inhibited proliferative activity (54% and 73%; P < 0.05) and neointima formation (53% and 67%; P < 0.05) in lean and obese animals, respectively. The vascular injury response in the face of obesity and the metabolic syndrome is associated with increased adhesion molecule expression, inflammatory cell infiltration, oxidized LDL receptor expression, and proliferation. iNOS gene transfer is able to effectively inhibit this heightened injury response and reduce neointima formation in this proinflammatory environment.

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Abstract 244: Distinct Regulation of Fat and Dachsous Cadherins in Response to Arterial Injury

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.37.suppl_1.244 ◽

2017 ◽

Vol 37 (suppl_1) ◽

Author(s):

Dario F Riascos-Bernal ◽

Longyue L Cao ◽

Prameladevi Chinnasamy ◽

Rong Hou ◽

Nicholas E Sibinga

Keyword(s):

Vascular Injury ◽

Molecular Mechanisms ◽

Transmembrane Protein ◽

Expression Profiles ◽

Control Cell ◽

Arterial Injury ◽

Type I ◽

Injury Response ◽

Neointimal Formation ◽

Electron Transport Complexes

Molecular mechanisms that control the activities of vascular smooth muscle cells (VSMCs) in the diseased or injured arterial wall remain incompletely understood. The atypical cadherin FAT1 is prominently expressed in VSMCs after vascular injury. In recent work, we found that processing of FAT1, a type I transmembrane protein, releases its intracellular domain, the FAT1ICD; in turn, FAT1ICD fragments accumulate in mitochondria and interact with electron transport complexes I and II to restrict VSMC respiration and control cell growth and neointimal formation. We hypothesized that FAT1 processing (and therefore these VSMC activities) is controlled by extracellular ligands that may interact physically via FAT1’s extended cadherin repeat or transmembrane domains. FAT4 and Dachsous 1 (DCHS1) are leading candidates for such interactions, but these proteins have not been studied in VSMCs or vascular injury response. Accordingly, we analyzed expression profiles of FAT4 and Dachsous 1 (DCHS1) during the vascular response to injury, using a rat carotid artery balloon injury model. Interestingly, FAT4 transcripts increased transiently after injury, peaking at day 7 (6.99±0.21-fold over baseline, P<.001), in a pattern reminiscent of FAT1. In contrast, DCHS1 levels decreased by day 3 after injury (0.49±0.02-fold of baseline, P<.001), remained low through day 14, and recovered by day 30. Physical interactions of FAT4 either with DCHS1 or with FAT1 have both been reported previously; therefore, decreased DCHS1 coincident with increased FAT4 suggest an increase in FAT4 availability and/or interaction with FAT1 during injury response. How this increase in FAT4 affects FAT1 function and VSMC metabolism and growth is the subject of ongoing investigation. FAT1 induction and processing after vascular injury represent an important novel molecular mechanism by which VSMC metabolism and growth are controlled after vascular injury. Increased availability of FAT4 cadherin due to FAT4 induction together with DCHS1 downregulation after vascular injury provides a likely upstream regulatory mechanism to govern FAT1 activities.

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