Vascular Proliferative Diseases Research Articles

Janus Kinase 3, a Novel Regulator for Smooth Muscle Proliferation and Vascular Remodeling.

Vascular remodeling because of smooth muscle cell (SMC) proliferation is a common process occurring in several vascular diseases, such as atherosclerosis, aortic aneurysm, post-transplant vasculopathy, restenosis after angioplasty, etc. The molecular mechanism underlying SMC proliferation, however, is not completely understood. The objective of this study is to determine the role and mechanism of Janus kinase 3 (JAK3) in vascular remodeling and SMC proliferation. Platelet-derived growth factor-BB, an SMC mitogen, induces JAK3 expression and phosphorylation while stimulating SMC proliferation. Janex-1, a specific inhibitor of JAK3, or knockdown of JAK3 by short hairpin RNA, inhibits the SMC proliferation. Conversely, ectopic expression of JAK3 promotes SMC proliferation. Mechanistically, JAK3 promotes the phosphorylation of signal transducer and activator of transcription 3 and c-Jun N-terminal kinase in SMC, 2 signaling pathways known to be critical for SMC proliferation and vascular remodeling. Blockade of these 2 signaling pathways by their inhibitors impeded the JAK3-mediated SMC proliferation. In vivo, knockdown of JAK3 attenuates injury-induced neointima formation with attenuated neointimal SMC proliferation. Knockdown of JAK3 also induces neointimal SMC apoptosis in rat carotid artery balloon injury model. Our results demonstrate that JAK3 mediates SMC proliferation and survival during injury-induced vascular remodeling, which provides a potential therapeutic target for preventing neointimal hyperplasia in proliferative vascular diseases.

Abstract 261: EBP50/NHERF-1 Regulates Basal and TNFα-induced Mitochondrial Dynamics in Vascular Smooth Muscle Cells

Mitochondrial dysfunction has been associated with the phenotypic switch of VSMC and vascular disease. Changes in mitochondrial dynamics (fission and fusion) are linked to VSMC proliferation and metabolism during vascular remodeling. Mitochondrial fission and fusion are regulated by several key molecules, including dynamin-related protein 1 (Drp1) and mitofusin2 (Mfn2). We previously showed that scaffolding Ezrin-radixin-moesin binding phosphoprotein of 50 kDa (EBP50/NHERF1) increases inflammatory responses and proliferation of VSMC. These actions are mediated by the activation of PKCζ under inflammatory stimuli and the stabilization of the S-phase kinase associated protein 2 (Skp2), a component of an E3 ligase that promotes proliferation. Thus, EBP50 knockout (EBP50 -/- ) mice are protected neointimal hyperplasia following arterial injury. Here we test the hypothesis that EBP50 regulates mitochondrial dynamics and responses to inflammatory stimuli in vascular smooth muscle cells (VSMC). We found that EBP50 knockdown, by decreasing Skp2 levels, increased FoxO1 stability and nuclear localization leading to higher mitofusin-2 (Mfn-2) expression. In contrast, inhibition of FoxO1 reduced Mfn2 levels. High resolution morphological analysis with both TEM and confocal microscopy revealed that mitochondria were more elongated in EBP50 -/- than WT VSMC. In WT VSMC, TNFα induced PKCζ-mediated phosphorylation of Drp1. In contrast, EBP50 -/- VSMC exhibited significantly reduced Drp1 phosphorylation following TNFα treatment. Live-cell 3D imaging followed by morphological analysis showed that TNFα elicited rapid and significantly greater mitochondria fragmentation in WT compared to EBP50 -/- VSMC. Finally, EBP50 -/- VSMC exhibited lower extracellular acidification rate (ECAR) than WT VSMC consistent with their lower proliferation. Collectively, these findings delineate a new mechanism of regulation of mitochondrial dynamics by the scaffolding protein EBP50 in response to inflammatory stimuli. Therefore EBP50 can be viewed as a potential therapeutic target for vascular proliferative diseases.

Roscovitine Protects From Arterial Injury by Regulating the Expressions of c-Jun and p27 and Inhibiting Vascular Smooth Muscle Cell Proliferation.

Roscovitine (Rosc) is a selective inhibitor of cyclin-dependent kinases (CDKs) and a promising therapy for various cancers. However, limited information is available on the biological significance of Rosc in vascular smooth muscle cells (VSMCs), the cell type critical for the development of proliferative vascular diseases. In this study, we address the effects of Rosc in regulating VSMC proliferation, both in vitro and in vivo, exploring the underlying molecular mechanisms. The proliferations and cell-cycle distributions of in vitro cultured VSMCs, as well as several other cancer cell lines, were examined by cell-counting assay and flow cytometry, respectively. Molecular changes in various CDKs, cyclins, and other regulatory molecules were examined by reverse transcription polymerase chain reaction, Western blot, or immunocytochemistry. The in vivo effects of Rosc were examined on a carotid arterial balloon-injury model. Rosc significantly inhibited VSMC proliferation in response to serum or angiotensin II and arrested these cells at the G0/G1 phase. These changes were associated with a specific and robust decrease in CDK4, cyclin E, c-Jun, and a dramatic increase in p27kip1 in VSMCs, which was also translated in vivo and correlated with the protection of Rosc on injury-induced neointimal hyperplasia. Acting on distinct molecular targets in VSMCs versus cancer cells, Rosc inhibits VSMC proliferation and protects from proliferative vascular diseases.

MicroRNA-182 prevents vascular smooth muscle cell dedifferentiation via FGF9/PDGFRβ signaling.

The abnormal phenotypic transformation of vascular smooth muscle cells (SMCs) causes various proliferative vascular diseases. MicroRNAs (miRNAs or miRs) have been established to play important roles in SMC biology and phenotypic modulation. This study revealed that the expression of miR-182 was markedly altered during rat vascular SMC phenotypic transformation in vitro. We aimed to investigate the role of miR-182 in the vascular SMC phenotypic switch and to determine the potential molecular mechanisms involved. The expression of miR-182 gene was significantly downregulated in cultured SMCs during dedifferentiation from a contractile to a synthetic phenotype. Conversely, the upregulation of miR-182 increased the expression of SMC-specific contractile genes, such as α-smooth muscle actin, smooth muscle 22α and calponin. Additionally, miR-182 overexpression potently inhibited SMC proliferation and migration under both basal conditions and under platelet-derived growth factor-BB stimulation. Furthermore, we identified fibroblast growth factor 9 (FGF9) as the target gene of miR-182 for the phenotypic modulation of SMCs mediated through platelet-derived growth factor receptor β (PDGFRβ) signaling. These data suggest that miR-182 may be a novel SMC phenotypic marker and a modulator that may be used to prevent SMC dedifferentiation via FGF9/PDGFRβ signaling.

Inhibition of estrogen related receptor α attenuates vascular smooth muscle cell proliferation and migration by regulating RhoA/p27Kip1 and β-Catenin/Wnt4 signaling pathway

RhoA/p27Kip1 and β-Catenin/Wnt4 signaling processes play central roles in proliferation and migration in vascular smooth muscle cells (VSMCs). ERRα, a member of orphan nuclear receptors, is a potent prognostic factor in breast, ovarian, colon and other types of tumors. However, biological significance of ERRα in VSMCs as well as the molecular mechanisms remains largely unknown. Therefore, the present study was designed to investigate whether ERRα is involved in the proliferation and migration of VSMCs in vitro and neointimal formation in vivo.The specific ERRα inverse agonist XCT790 (or ERRα shRNA) resulted in a significant inhibition of proliferation and phenotypic switch in cultured rat aortic SMCs (RASMCs). Furthermore, cycle progression, cell cycle protein transcription as well as hyperphosphorylation of the retinoblastoma protein (Rb) in RASMCs were prevented by downregulation of ERRα. Transwell assay demonstrated that migratory capacity of RASMCs was also inhibited the treatment of XCT790 (or ERRα shRNA). At the molecular levels, RhoA/p27Kip1 and β-Catenin/Wnt4 signaling pathways are involved in ERRα-mediated RASMCs growth and migration. Finally, inhibition of ERRα significantly attenuated neointimal formation in rat artery after balloon injury. These results help to further understand vascular remodeling and suggest that ERRα might be a potential target for the treatment of vascular proliferative diseases.

Lipopolysaccharide induced vascular smooth muscle cells proliferation: A new potential therapeutic target for proliferative vascular diseases.

Vascular smooth muscle cells (VSMCs) proliferation is involved in vascular atherosclerosis and restenosis. Recent studies have demonstrated that lipopolysaccharide (LPS) promotes VSMCs proliferation, but the signalling pathways which are involved are not completely understood. The purpose of this review was to summarize the existing knowledge of the role and molecular mechanisms involved in controlling VSMCs proliferation stimulated by LPS and mediated by toll-like receptor 4 (TLR4) signalling pathways. Moreover, the potential inhibitors of TLR4 signalling for VSMCs proliferation in proliferative vascular diseases are discussed.

Olfactomedin 2 Regulates Smooth Muscle Phenotypic Modulation and Vascular Remodeling Through Mediating Runt-Related Transcription Factor 2 Binding to Serum Response Factor.

The objective of this study is to investigate the role and underlying mechanism of Olfactomedin 2 (Olfm2) in smooth muscle cell (SMC) phenotypic modulation and vascular remodeling. Platelet-derived growth factor-BB induces Olfm2 expression in primary SMCs while modulating SMC phenotype as shown by the downregulation of SMC marker proteins. Knockdown of Olfm2 blocks platelet-derived growth factor-BB-induced SMC phenotypic modulation, proliferation, and migration. Conversely, Olfm2 overexpression inhibits SMC marker expression. Mechanistically, Olfm2 promotes the interaction of serum response factor with the runt-related transcription factor 2 that is induced by platelet-derived growth factor-BB, leading to a decreased interaction between serum response factor and myocardin, causing a repression of SMC marker gene transcription and consequently SMC phenotypic modulation. Animal studies show that Olfm2 is upregulated in balloon-injured rat carotid arteries. Knockdown of Olfm2 effectively inhibits balloon injury-induced neointima formation. Importantly, knockout of Olfm2 in mice profoundly suppresses wire injury-induced neointimal hyperplasia while restoring SMC contractile protein expression, suggesting that Olfm2 plays a critical role in SMC phenotypic modulation in vivo. Olfm2 is a novel factor mediating SMC phenotypic modulation. Thus, Olfm2 may be a potential target for treating injury-induced proliferative vascular diseases.

Viscolin Inhibits In Vitro Smooth Muscle Cell Proliferation and Migration and Neointimal Hyperplasia In Vivo.

Viscolin, an extract of Viscum coloratum, has anti-inflammatory and anti-proliferative properties against harmful stimuli. The aim of the study was to examine the anti-proliferative effects of viscolin on platelet derived growth factor-BB (PDGF)-treated human aortic smooth muscle cells (HASMCs) and identify the underlying mechanism responsible for these effects. Viscolin reduced the PDGF-BB-induced HASMC proliferation and migration in vitro; it also arrested HASMCs in the G0/G1 phase by decreasing the protein expression of Cyclin D1, CDK2, Cyclin E, CDK4, and p21Cip1 as detected by Western blot analysis. These effects may be mediated by reduced PDGF-induced phosphorylation of ERK1/2, JNK, and P38, but not AKT as well as inhibition of PDGF-mediated nuclear factor (NF)-κB p65 and activator protein 1 (AP-1)/c-fos activation. Furthermore, viscolin pre-treatment significantly reduced neointimal hyperplasia of an endothelial-denuded femoral artery in vivo. Taken together, viscolin attenuated PDGF–BB-induced HASMC proliferation in vitro and reduced neointimal hyperplasia in vivo. Thus, viscolin may represent a therapeutic candidate for the prevention and treatment of vascular proliferative diseases.

HHEX: A Crosstalker between HCMV Infection and Proliferation of VSMCs.

Objective: The study was designed to evaluate the role of Human cytomegalovirus (HCMV) infection on homebox (HOX) gene expression and the effects of overexpression of HOX genes on proliferation and apoptosis of vascular smooth muscle cells (VSMCs).Methods: Viral infection was verified by observation of cytopathic effects through inverted microscopy, viral particles by electron microscopy and HCMV IE gene amplification by RT-PCR. cDNA profiling technology was used to screen expression of HOX genes after HCMV infection in VSMCs. Abnormal expression of Haematopoietically-expressed homeobox (HHEX) was selected to construct over-expressed vector and transfected into VSMCs. The effects of over expression of HHEX on cell proliferation and apoptosis of VSMCs were assayed by flow cytometry. Apoptosis and proliferation-associated genes were also assayed by RT-PCR.Results: Multiple HOX gene expression levels had obvious changes after HCMV infection, among which expression of HHEX gene increased obviously at 24, 48, and 72 h after infection. Over expression of HHEX can promote VSMCs proliferation by promoting G0/G1 phase cells into S phase and inhibit VSMCs apoptosis. HHEX inhibited the expression of apoptosis-associated caspase 2 and caspase3 and promoted the expression of cell cycle-related genes such as CDK2 and CDK6, CyclinB2 and CyclinD2.Conclusion: HHEX over expression induced by HCMV infection closely associated with vascular proliferative diseases.

High Mobility Group Box 1 Mediates Interferon-γ-Induced Phenotypic Modulation of Vascular Smooth Muscle Cells.

The phenotypic modulation of VSMCs is a key cellular event driving neointimal formation and vascular remodeling. As a multifaceted cytokine of cell-mediated immunity, IFN-γ has been shown to play a critical role in the pathogenesis of vascular proliferative diseases. Although the important function of IFN-γ on regulating VSMC activation is well established, the molecular mechanisms by which elicits VSMC responses are poorly defined. Recent studies have identified HMGB1 as a principal effector to mediate IFN-γ-dependent biological functions in multiple cell types. Moreover, SIRT1 has emerged as a critical regulator of cellular processes through deacetylating multiple substrates, including HMGB1. Thus, we examined the role of IFN-γ on HMGB1 release, SIRT1 expression, and VSMC phenotypic modulation as well as the underlying molecular mechanisms. We show that IFN-γ dose-dependently induces HMGB1 cytoplasmic accumulation and its active release from VSMCs, resulting in enhanced HMGB1 in the medium. Conversely, IFN-γ treatment led to a dramatic decrease in SIRT1 expression. Additionally, pretreatment with resveratrol, a selective SIRT1 activator, abrogated IFN-γ-induced HMGB1 translocation and its release. Moreover, IFN-γ stimulates VSMC phenotypic modulation to an activated synthetic state characterized by the repression of SMC differentiation markers such as SM22α and calponin and the increase in cell motility. In contrast, blocking HMGB1 release or activity by resveratrol and HMGB1-neutralizing antibody prevents IFN-γ-induced phenotypic modulation of VSMCs. Overall, this study provides the first evidence showing that HMGB1 plays a critical role in regulating VSMC phenotypic modulation, suggesting that HMGB1 may be a potential therapeutic target to prevent vascular occlusive diseases. J. Cell. Biochem. 118: 518-529, 2017. © 2016 Wiley Periodicals, Inc.

Inhibition of Epac1 suppresses mitochondrial fission and reduces neointima formation induced by vascular injury.

Vascular smooth muscle cell (VSMC) activation in response to injury plays an important role in the development of vascular proliferative diseases, including restenosis and atherosclerosis. The aims of this study were to ascertain the physiological functions of exchange proteins directly activated by cAMP isoform 1 (Epac1) in VSMC and to evaluate the potential of Epac1 as therapeutic targets for neointima formation during vascular remodeling. In a mouse carotid artery ligation model, genetic knockdown of the Epac1 gene led to a significant reduction in neointima obstruction in response to vascular injury. Pharmacologic inhibition of Epac1 with an Epac specific inhibitor, ESI-09, phenocopied the effects of Epac1 null by suppressing neointima formation and proliferative VSMC accumulation in neointima area. Mechanistically, Epac1 deficient VSMCs exhibited lower level of PI3K/AKT signaling and dampened response to PDGF-induced mitochondrial fission and reactive oxygen species levels. Our studies indicate that Epac1 plays important roles in promoting VSMC proliferation and phenotypic switch in response to vascular injury, therefore, representing a therapeutic target for vascular proliferative diseases.

Factor VII‐activating protease deficiency promotes neointima formation by enhancing leukocyte accumulation

Background Factor VII-activating protease (FSAP) is a multifunctional circulating plasma serine protease involved in thrombosis and vascular remodeling processes. The Marburg I single-nucleotide polymorphism (MI-SNP) in the FSAP-coding gene is characterized by low proteolytic activity, and is associated with increased rates of stroke and carotid stenosis in humans. Objectives To determine whether neointima formation after vascular injury is increased in FSAP-/- mice. Methods and Results The neointimal lesion size and the proliferation of vascular smooth muscle cells (VSMCs) were significantly enhanced in FSAP-/- mice as compared with C57BL/6 control mice after wire-induced injury of the femoral artery. Accumulation of leukocytes and macrophages was increased within the lesions of FSAP-/- mice at day 3 and day 14. Quantitative zymography demonstrated enhanced activity of gelatinases/matrix metalloproteinase (MMP)-2 and MMP-9 within the neointimal lesions of FSAP-/- mice, and immunohistochemistry showed particular costaining of MMP-9 with accumulating leukocytes. Using intravital microscopy, we observed that FSAP deficiency promoted the intravascular adherence and the subsequent transmigration of leukocytes in vivo in response to chemokine ligand 2 (CCL2). CCL2 expression was increased in FSAP-/- monocytes but not in the vessel wall. There was no difference in the expression of platelet-derived growth factor (PDGF-BB). Conclusions FSAP deficiency causes an increase in CCL2 expression and CCL2-mediated infiltration of leukocytes into the injured vessel, thereby promoting SMC proliferation and migration by the activation of leukocyte-derived gelatinases. These results provide a possible explanation for the observed association of the loss-of-function MI-SNP with vascular proliferative diseases.

Differential Expression of MicroRNAs in Endarterectomy Specimens Taken from Patients with Asymptomatic and Symptomatic Carotid Plaques.

ObjectiveStroke and transient ischemic attacks are considered as clinical manifestations of atherosclerotic disease due to on-going vascular inflammation and finally atherothrombosis of the carotid arteries. MicroRNAs (miRNA/miR) are known to be involved in vascular inflammation and plaque destabilization. The aim of this study was to analyze the expression profile of selected miRNAs in endarterectomy specimen from carotid arteries that were taken from patients with asymptomatic and symptomatic atherosclerotic plaques.Methods and Results11 miRNAs were selected and their expression was analyzed using real-time RT-PCR. Therefore, samples were divided into three different groups. On the one hand we investigated the expression patterns from patients in asymptomatic (n = 14) and symptomatic (n = 10) plaques; on the other hand we took samples from normal configurated internal mammary arteries (n = 15). Out of these 11 targets we identified some miRNAs, which were up- or down-regulated in either one of the two groups. Interestingly, the expression of two miRNAs was significantly different between asymptomatic and symptomatic samples, namely miR-21 (P<0.01) and miR-143 (P<0.05).ConclusionIn the present study, we identified miRNA subtypes which showed different expression in endarterectomy specimen from patients with asymptomatic and symptomatic plaques, suggesting that these miRNAs correlated with advanced vascular inflammation and plaque stability. They may represent new therapeutic targets for vascular proliferative diseases such as atherosclerosis.

Tissue-Engineered Vascular Rings from Human iPSC-Derived Smooth Muscle Cells.

SummaryThere is an urgent need for an efficient approach to obtain a large-scale and renewable source of functional human vascular smooth muscle cells (VSMCs) to establish robust, patient-specific tissue model systems for studying the pathogenesis of vascular disease, and for developing novel therapeutic interventions. Here, we have derived a large quantity of highly enriched functional VSMCs from human induced pluripotent stem cells (hiPSC-VSMCs). Furthermore, we have engineered 3D tissue rings from hiPSC-VSMCs using a facile one-step cellular self-assembly approach. The tissue rings are mechanically robust and can be used for vascular tissue engineering and disease modeling of supravalvular aortic stenosis syndrome. Our method may serve as a model system, extendable to study other vascular proliferative diseases for drug screening. Thus, this report describes an exciting platform technology with broad utility for manufacturing cell-based tissues and materials for various biomedical applications.

Heme Oxygenase-1 and Carbon Monoxide in the Heart

Understanding the processes governing the ability of the heart to repair and regenerate after injury is crucial for developing translational medical solutions. New avenues of exploration include cardiac cell therapy and cellular reprogramming targeting cell death and regeneration. An attractive possibility is the exploitation of cytoprotective genes that exist solely for self-preservation processes and serve to promote and support cell survival. Although the antioxidant and heat-shock proteins are included in this category, one enzyme that has received a great deal of attention as a master protective sentinel is heme oxygenase-1 (HO-1), the rate-limiting step in the catabolism of heme into the bioactive signaling molecules carbon monoxide, biliverdin, and iron. The remarkable cardioprotective effects ascribed to heme oxygenase-1 are best evidenced by its ability to regulate inflammatory processes, cellular signaling, and mitochondrial function ultimately mitigating myocardial tissue injury and the progression of vascular-proliferative disease. We discuss here new insights into the role of heme oxygenase-1 and heme on cardiovascular health, and importantly, how they might be leveraged to promote heart repair after injury.

MicroRNA-30 inhibits neointimal hyperplasia by targeting Ca(2+)/calmodulin-dependent protein kinase IIδ (CaMKIIδ).

The multifunctional Ca2+/calmodulin-dependent protein kinase II δ-isoform (CaMKIIδ) promotes vascular smooth muscle (VSM) proliferation, migration, and injury-induced vascular wall neointima formation. The objective of this study was to test if microRNA-30 (miR-30) family members are endogenous regulators of CaMKIIδ expression following vascular injury and whether ectopic expression of miR-30 can inhibit CaMKIIδ-dependent VSM cell function and neointimal VSM hyperplasia induced by vascular injury. The CaMKIIδ 3′UTR contains a consensus miR-30 binding sequence that is highly conserved across species. A significant decrease in miR-30 family members and increase in CaMKIIδ2 protein expression, with no change in CaMKIIδ mRNA expression, was observed in medial layers of VSM 7 days post-injury. In vitro, overexpression of miR-30c or miR-30e inhibited CaMKIIδ2 protein expression by ~50% in cultured rat aortic VSM cells, and inhibited VSM cell proliferation and migration. In vivo, lenti-viral delivery of miR-30c into injured rat carotid arteries prevented the injury-induced increase in CaMKIIδ2. Furthermore, neointima formation was dramatically inhibited by lenti-viral delivery of miR-30c in the injured medial smooth muscle. These studies define a novel mechanism for regulating CaMKIIδ expression in VSM and provide a new potential therapeutic strategy to reduce progression of vascular proliferative diseases, including atherosclerosis and restenosis.

Efficacy and mechanism of local delivery of rapamycin and rapamycin-loaded poly(lactic-co-glycolic) acid nanoparticles on coronary restenosis of injury-stenosis model of minipigs

To determine whether intramural administration of rapamycin (RPM)-loaded polylactic-polyglycolic acid (PLGA) nanoparticles (NPs) can reduce intimal thickening and affect the mRNA expressions of matrix metalloproteinase (MMP)-2, tissue inhibitor of metalloproteinase (TIMP)-2 and p27(kipl) in a coronary injury-stenosis model of minipigs. Twenty eight minipigs were randomly separated into four groups: saline group (n=7), blank PLGA NPs group (5.0 mg/ml)(n=7), RPM group (1.0 mg/ml)(n=7), and RPM-PLGA NPs(5.0 mg/ml)group (n=7), respectively. Different treatments were intracoronary locally delivered via a Dispatch™ catheter for 10 minutes. Serial angiography was performed pre-and post-modeling 30 days and the percent stenosis degree was assessed. Hematoxylin-Eosin (HE) staining, Weigert's resorcin fuchsin staining and picric acid-sirius red staining were used for morphometric analysis. Immunohistochemistry was performed to assess the levels of proliferating cell nuclear antigen (PCNA), MMP-2, and TIMP-2 at early and late time points, respectively. The expression of p27(kip1) mRNA was detected by in situ hybridization staining. Data from 21 minipigs had been collected at the end of the experiment with 6, 4, 5, and 6 from the former mentioned 4 groups, respectively. For the instant injury index, there was no significant difference among the four groups. The percent stenosis degree of RPM-PLGA NPs group was significantly lower than that of the other three groups respectively (all P< 0.05). The neointima area, net external elastic lamina area to external elastic laminal area ratio, and proliferative index of RPM-PLGA NPs group were significantly less than those of the other three groups, with all the P values less than 0.05. The mean value of integral optical density of p27(kip1)mRNA expression of RPM-PLGA group was 0.35 ± 0.06, higher than that of blank PLGA NPs group (0.12 ± 0.05, P< 0.01), saline group (0.16 ± 0.03, P< 0.05), and RPM group (0.15 ± 0.03, P< 0.05), respectively. The MMP-2/TIMP-2 ratio and the positive expression index of PCNA in RPM-PLGA group were lower than that of the other groups (P< 0.05). Locally delivered rapamycin-loaded PLGA NPs significantly reduces MMP-2/TIMP-2 ratio and PCNA expression, increases p27(kip1) mRNA expression and significantly relieves percent stenosis degree and shows excellent acute procedural results in the minipig interventional coronary artery oversized balloon injury model. The results from minipig model further support that this approach could be a potential clinical procedure for vascular proliferative disease.

Association of genetic variations in miR-146a rs2910164 and miR-149 rs11614913 with the development of classic Kaposi sarcoma.

Classic Kaposi sarcoma is a type of vascular proliferative inflammatory disease. Previous studies have reported significant associations between microRNAs expression and the development of classic Kaposi sarcoma. Here, we conducted a case-control study to investigate the association between miR-146a and miR-149 genetic polymorphisms and risk of classic Kaposi sarcoma in a Chinese population. Both classic Kaposi sarcoma patients and healthy controls were recruited between December 2013 and October 2015. Genotyping of miR-146a and miR-149 was performed by polymerase chain reaction-coupled with restriction fragment length polymorphism. Results showed that the GG genotype of miR-146a was associated with increased risk to classic Kaposi sarcoma (OR = 6.00, 95%CI = 1.19-30.12), as compared with the CC genotype. In the recessive model, we found that the GG genotype carried a 4.55-fold increased risk to classic Kaposi sarcoma as compared with the CC + CG genotype (OR = 2.06, 95%CI = 1.04-20.29). In conclusion, our study demonstrated that miR-146a, but not miR-149 polymorphism, is associated with risk to classic Kaposi sarcoma in the Chinese population.

The Influence of Caldesmon Suppression on Proliferation and Motilities of Vascular Smooth Muscle Cells

Migration of vascular smooth muscle cells (VSMCs) from the media to intima constitutes a critical step in the development of proliferative vascular diseases. To elucidate the regulatory mechanism of VSMCs motility, the roles of caldesmon (CaD) were investigated previously. CaD is an actin-binding protein dynamically regulating cytoskeleton structure. In this study, the potential role of CaD in mediating proliferation and motility of VSMCs were discussed. First, structural effect of CaD on cytoskeleton integrity was analyzed with CaD knock-down; second, the proliferation of VSMCs was measured in CaD knock-down and control cells; third, the specific role of CaD on VSMCs motilities was evaluated with in vitro migration and invasion assays. We found that CaD is an integral component to maintain cytoskeleton integrity of VSMCs. Our data indicated that CaD suppression does not show significant influence on VSMCs proliferation, but negatively modulates the motilities of VSMCs, and CaD depletion would significantly facilitate migration and invasion of VSMCs.

An overview of potential molecular mechanisms involved in VSMC phenotypic modulation.

The fully differentiated medial vascular smooth muscle cells (VSMCs) of mature vessels keep quiescent and contractile. However, VSMC can exhibit the plasticity in phenotype switching from a differentiated and contractile phenotype to a dedifferentiated state in response to alterations in local environmental cues, which is called phenotypic modulation or switching. Distinguishing from its differentiated state expressing more smooth muscle (SM)-specific/selective proteins, the phenotypic modulation in VSMC is characterized by an increased rate of proliferation, migration, synthesis of extracellular matrix proteins and decreased expression of SM contractile proteins. Although it has been well demonstrated that phenotypic modulation of VSMC contributes to the occurrence and progression of many proliferative vascular diseases, little is known about the details of the molecular mechanisms of VSMC phenotypic modulation. Growing evidence suggests that variety of molecules including microRNAs, cytokines and biochemical factors, membrane receptors, ion channels, cytoskeleton and extracellular matrix play important roles in controlling VSMC phenotype. The focus of the present review is to provide an overview of potential molecular mechanisms involved in VSMC phenotypic modulation in recent years. To clarify VSMC differentiation and phenotypic modulation mechanisms will contribute to producing cell-based therapeutic interventions for aberrant VSMC differentiation-related diseases.