A systematic review and bioinformatic study on clinical, paraclinical, and genetic factors predisposing to stent restenosis following percutaneous coronary intervention.

BACKGROUND: Stent restenosis is a relatively common phenomenon among patients with coronary heart disease undergoing percutaneous coronary intervention (PCI). It seems that a set of clinical, laboratory, and even genetic factors make people susceptible to such a phenomenon and in fact, this is multi-factorial. We aimed to first determine the underlying clinical and laboratory risk factors for the occurrence of stent re-stenosis after PCI based on a systematic review study, and after that, through a bioinformatics study, to evaluate the related genes and microRNAs with the occurrence of stent re-stenosis. MAIN TEXT: In the first step, the manuscript databases including Medline, Web of Knowledge, Google Scholar, Scopus, and Cochrane were deeply searched by the two blinded investigators for all eligible studies based on the considered keywords to introduce clinical and laboratory determinants of stent re-stenosis. In the bioinformatic phase, and following a review of the literature to identify genes and microRNAs involved in restenosis, the interaction of each gene with other genes associated with stent re-stenosis was determined by GeneMANIA network analysis and Cytoscape software. Overall, 67 articles (including 40,789 patients) on clinical and biochemical predictors for stent restenosis and 25 articles on genetic determinants of this event were eligible for the final analysis. The predictors for this event were categorized into four subgroups patient-based parameters including traditional cardiovascular risk profiles, stent-based parameters including type and diametric characteristics of the stents used, coronary lesion-based parameters including several two target lesions and coronary involvement severity and laboratory-based parameters particularly related to activation of inflammatory processes. In the bioinformatic phase, we uncovered 42 genes that have been described to be involved in such a phenomenon considering a special position for genes encoding inflammatory cytokines. Also, 12 microRNAs have been pointed to be involved in targeting genes involved in stent re-stenosis. CONCLUSIONS: The incidence of stent re-stenosis will be the result of a complex interaction of clinical risk factors, laboratory factors mostly related to the activation of inflammatory processes, and a complex network of gene-to-gene interactions.

Association of ACE gene polymorphisms with in-stent restenosis by stent type (biomime, supraflex, xience).

INTRODUCTION: Angiotensin Converting Enzyme or ACE is an exo-peptidase that causes the conversion of angiotensin I to angiotensin II, vasoconstriction, and aldosterone production. ACE gene polymorphism (I/D) affects enzyme activity and the risk of coronary artery disease or CAD. AIMS: To examine the role of ACE (I/D) Gene Polymorphisms by Stent Types (Biomime, Supraflex, Xience) the Ace gene allele and genotype frequencies were determined in patients who underwent angioplasty. MATERIAL & METHODS: Patients with in-stent restenosis (ISR+) (N = 53) and patients as non-ISR group (ISR-) (N = 68) have been enrolled in this study based on follow-up angiography > 1 year after PCI. Frequencies of allele and genotypes of the ACE (I/D) variant were determined using polymerase chain reaction (PCR). RESULTS: The genotypes and allele frequencies were not significantly different between the studied populations (p-Values > 0.05). However, there was a significant difference between people with a history of Clopidogrel use in the ISR- and ISR + groups observed (p-Values > 0.005). CONCLUSION: In the present study, there was no statistically significant relationship between ACE (I/D) gene polymorphism and the incidence of restenosis in patients who underwent repeat angiography. The results showed that the number of patients who received Clopidogrel in the ISR + group was significantly less than the ISR- group. This issue can indicate the inhibitory effect of Clopidogrel in the recurrence of stenosis.

Candidate Gene of NOS3, MMP3, AGT, and AGT1R and Pathway Analyses for Platelet Reactivity and Clinical Outcomes of Repeat Revascularization After First PCI in Chinese Patients.

PURPOSE: Major disadvantages of the percutaneous coronary intervention (PCI) are the high occurrence of repeat revascularization due to restenosis and disease progression. The current study aimed to identify indicators that can predict the risk of repeat revascularization. METHODS: A total of 143 patients who underwent PCI and had genetic test results were enrolled. We retrospectively reviewed their medical records after the first PCI. P2Y12 reaction unit (PRU) test results were obtained by VerifyNow; 4 candidate genes (NOS3, MMP3, AGT, and AGT1R) and 380 genes related to platelet activation-related processes and clopidogrel activity were selected for analysis. Repeat revascularization and in-stent restenosis (ISR) were used as clinical outcomes, and PRU and ADP aggregation rates were used as platelet function outcomes in analysis. RESULTS: After the first PCI, the incidence of repeat revascularization at 18, 30, and 42 months was 14.1% (20/142), 17.5% (24/137), and 39.7% (31/78), respectively. In the candidate gene analysis, rs7830 (NOS3) was associated with both ADP aggregation rate and 18- and 30-month ISR, and rs 62,275,847 (AGTR1) was associated with both ADP aggregation rate and 30-month ISR. In the pathway, gene-set analysis, the linkage rs471683 and rs7785386 of GNAI1|GNAT3 were associated with PRU and ADP aggregation rate, 18-month and 30-month ISR, and repeat revascularization within 30 months. Rs1715389 of GNAI1|GNAT3 was associated with both PRU and ADP aggregation rate, 18-month and 30-month ISR, and repeat revascularization within 30 months. Rs7313458 of ITPR2 was associated with PRU and ADP aggregation rate, 18-month and 30-month ISR, and repeat revascularization within 18 months. CONCLUSIONS: The genetic polymorphisms of rs7830 (NOS3), rs62275874 (AGTR1), linkage rs471683 and rs7785386 (GNAI1|GNAT3), rs1715389 (GNAI1|GNAT3), and rs7313458 (ITPR2) may lead to an increased risk of in-stent restenosis and revascularization after the first PCI in Chinese patients by affecting the efficacy of clopidogrel. The above six SNP may be used as potential genetic biomarkers for high risk of in-stent restenosis and revascularization after the first PCI in Chinese patients.

Long Non-Coding RNAs Might Regulate Phenotypic Switch of Vascular Smooth Muscle Cells Acting as ceRNA: Implications for In-Stent Restenosis.

Coronary in-stent restenosis is a late complication of angioplasty. It is a multifactorial process that involves vascular smooth muscle cells (VSMCs), endothelial cells, and inflammatory and genetic factors. In this study, the transcriptomic landscape of VSMCs' phenotypic switch process was assessed under stimuli resembling stent injury. Co-cultured contractile VSMCs and endothelial cells were exposed to a bare metal stent and platelet-derived growth factor (PDGF-BB) 20 ng/mL. Migratory capacity (wound healing assay), proliferative capacity, and cell cycle analysis of the VSMCs were performed. RNAseq analysis of contractile vs. proliferative VSMCs was performed. Gene differential expression (DE), identification of new long non-coding RNA candidates (lncRNAs), gene ontology (GO), and pathway enrichment (KEGG) were analyzed. A competing endogenous RNA network was constructed, and significant lncRNA-miRNA-mRNA axes were selected. VSMCs exposed to "stent injury" conditions showed morphologic changes, with proliferative and migratory capacities progressing from G0-G1 cell cycle phase to S and G2-M. RNAseq analysis showed DE of 1099, 509 and 64 differentially expressed mRNAs, lncRNAs, and miRNAs, respectively. GO analysis of DE genes showed significant enrichment in collagen and extracellular matrix organization, regulation of smooth muscle cell proliferation, and collagen biosynthetic process. The main upregulated nodes in the lncRNA-mediated ceRNA network were PVT1 and HIF1-AS2, with downregulation of ACTA2-AS1 and MIR663AHG. The PVT1 ceRNA axis appears to be an attractive target for in-stent restenosis diagnosis and treatment.

The CTGF gene -945 G/C polymorphism is associated with target lesion revascularization for in-stent restenosis.

BACKGROUND AND AIMS: Previous studies have shown that transforming growth factor ß (TGF-ß) and vascular endothelial growth factor A (VEGF-A) pathways are involved in the in-stent restenosis (ISR) process. The present study aimed to assess the relationship between single-nucleotide polymorphisms (SNPs) in genes encoding downstream proteins of TGF-ß and VEGF-A pathways and the risk of target lesion revascularization (TLR) for in-stent restenosis. METHODS: A total of 657 patients (with 781 treated lesions) who underwent percutaneous coronary intervention (PCI) with stent implantation at our center between 2007 and 2012 and completed a 4-year follow-up for clinically-driven TLR, were included. SNPs in CTGF (rs6918698), TGFBR2 (rs2228048), SMAD3 (rs17293632), KDR (rs2071559), CCL2 (rs1024610) were genotyped using TaqMan assay. RESULTS: Major allele carriers of CTGF gene -945 G/C polymorphism (rs6918698) were significantly less likely to underwent clinically-driven TLR during follow-up than minor allele carriers. After adjustment for clinical, angiographic, and procedural covariates, CTGF polymorphism was significantly associated with TLR, and minor allele (C) carriers had nearly two times higher risk of developing ISR requiring TLR (HR of 1.93, 95%CI 1.15-3.24) compared to patients with major (GG) genotype. No significant relationship was found between other analyzed polymorphisms and cumulative incidence of TLR at 4-years. CONCLUSIONS: Our results suggest that functional -945 G/C polymorphism in the gene encoding connective tissue growth factor is associated with the need for TLR in patients who underwent PCI for stable coronary artery disease.

ADA gene haplotype is associated with coronary-in-stent-restenosis.

BACKGROUND: Cardiovascular diseases (CVDs) are the most common and the first cause of death worldwide. While some studies have investigated the association of the Adenosine Deaminase (ADA) gene with CDVs, its roles on in-stent restenosis (ISR) has not been studied. METHODS AND RESULTS: In this study, we investigated the role of ADA gene variants in both genetic and haplotype models on the risk of ISR. 91 samples were included in this study. The subjects were divided into two groups regarding having or not-having ISR (n = 40 ISR+ and n = 51 ISR-). The genotyping for G22A (rs73598374) and A4223C (rs452159) polymorphisms was performed using PCR-RFLP method. Statistical analysis was performed by SPSS v. 20 and Haploview 4.2 softwares. The basic demographic conditions in ISR groups were statistically similar. There was a significant association between A allele of rs452159 ISR groups after adjustment (allelic model: P value = 0.028, OR(95%CI) = 0.366(0.149-0.899)), while rs73598374 polymorphism shows no significant association with ISR. In haplotype analysis, the GA (G:rs73598374/A:rs452159) haplotype decreased the risk of ISR (P value = 00.025, OR(95%CI) = 0.382(0.161-0.907)). CONCLUSIONS: This study suggests that A allele of ADA rs452159 polymorphism and GA (G:rs73598374/A:rs452159) haplotype may be related to decreased risk of ISR in CAD patients receiving drug-eluting stent and offers more observational studies on ADA variants in other populations to generate a potential haplotype panel for ISR risk assessment.

The Expanding Role of Alternative Splicing in Vascular Smooth Muscle Cell Plasticity.

Vascular smooth muscle cells (VSMCs) display extraordinary phenotypic plasticity. This allows them to differentiate or dedifferentiate, depending on environmental cues. The ability to 'switch' between a quiescent contractile phenotype to a highly proliferative synthetic state renders VSMCs as primary mediators of vascular repair and remodelling. When their plasticity is pathological, it can lead to cardiovascular diseases such as atherosclerosis and restenosis. Coinciding with significant technological and conceptual innovations in RNA biology, there has been a growing focus on the role of alternative splicing in VSMC gene expression regulation. Herein, we review how alternative splicing and its regulatory factors are involved in generating protein diversity and altering gene expression levels in VSMC plasticity. Moreover, we explore how recent advancements in the development of splicing-modulating therapies may be applied to VSMC-related pathologies.

miR-18a-5p Promotes Proliferation and Migration of Vascular Smooth Muscle Cells by Activating the AKT/Extracellular Regulated Protein Kinases (ERK) Signaling Pathway.

BACKGROUND microRNAs (miRNAs) play important roles in abnormal proliferation and migration of vascular smooth muscle cells (VSMCs), which lead to restenosis in coronary artery disease. Nevertheless, the role of miR-18a-5p and how it works in VSMCs remain unknown. MATERIAL AND METHODS miR-18a-5p expression was determined by fluorescence quantitative real-time polymerase chain reaction (qRT-PCR) analysis of tissues from 20 patients with stent restenosis, and rats with carotid artery injury, as well as VSMCs. A cell viability assay was used to measure cell proliferation. Cell migration abilities were assessed by transwell migration assay and wound healing assays. To identify miR-18a-5p targets, a dual-luciferase reporter assay was performed. Western blot analysis and immunofluorescence techniques were used to assess the protein expression levels of AKT and ERK. The rescue effects of miR-18a-5p on the proliferation or migration of VSMCs were evaluated after exposure to the AKT inhibitor MK-2206 and ERK inhibitor PD98059. RESULTS The expression level of miR-18a-5p was significantly higher in the blood serum of patients with stent restenosis and in rats with carotid artery injury, and the expression of AKT and ERK was higher after carotid artery injury. The proliferation and migration abilities of VSMCs were accelerated by the overexpression of miR-18a-5p. It was found that miR-18a-5p directly modulates AKT/ERK signaling. Upregulated miR-18a-5p increased the protein expression levels of AKT and ERK and we found a positive correlation between miR-18a-5p expression level and expression of AKT and ERK. Additionally, the promoting effect of miR-18a-5p on VSMCs proliferation, migration, and invasion was reversed by ERK inhibitor or AKT inhibitor. CONCLUSIONS miR-18a-5p can promote proliferation of VSMCs by activating the AKT/ERK signaling pathway.

Potential of circulating pro-angiogenic microRNA expressions as biomarkers for rapid angiographic stenotic progression and restenosis risks in coronary artery disease patients underwent percutaneous coronary intervention.

BACKGROUND: This study aimed to investigate the correlation of pro-angiogenic microRNA (miRNA) expressions with rapid angiographic stenotic progression (RASP) and restenosis risks in coronary artery disease (CAD) patients underwent percutaneous coronary intervention (PCI) with drug-eluting stents (DES). METHODS: A total of 286 CAD patients underwent PCI with DES were consecutively recruited in this study. Plasma samples were collected before PCI operation, and 14 pro-angiogenic miRNAs were measured by real-time quantitative reverse transcription-polymerase chain reaction. Rapid angiographic stenotic progression at nontarget lesions and restenosis at stented lesions were evaluated by quantitative coronary angiography at 12 months after PCI operation. RESULTS: The occurrence rates of RASP and restenosis were 39.5% and 22.4%, respectively. Let-7f, miR-19a, miR-19b-1, miR-92a, miR-126, miR-210, and miR-296 were decreased in RASP patients than non-RASP patients, among which let-7f, miR-19a, miR-126, miR-210, and miR-296 independently correlated with lower RASP occurrence by multivariate analysis, followed by receiver-operating characteristic (ROC) curve exhibited that these five miRNAs showed great value in predicting RASP risk with area under curve (AUC) 0.879 (95% CI: 0.841-0.917). Besides, let-7f, miR-19a, miR-92a, miR-126, miR-130a, and miR-210 were reduced in restenosis patients than non-restenosis patients, among them miR-19a, miR-126, miR-210, and miR-378 independently correlated with lower restenosis occurrence by multivariate analysis, followed by ROC curve disclosed that these four miRNAs had good value in predicting restenosis risk with AUC 0.776 (95% CI: 0.722-0.831). CONCLUSIONS: Circulating let-7f, miR-19a, miR-126, miR-210, and miR-296 independently correlate with reduced RASP risk, while miR-19a, miR-126, miR-210, and miR-378 independently correlate with decreased restenosis risk in CAD patients underwent PCI with DES.

Circulating microRNA-21 as Stable Blood-Based Markers for Patients With ISR After PCI.

It recently has been reported that the in-stent restenosis (ISR) of expanded area after percutaneous coronary intervention (PCI) within six months can become a serious postoperative complication. A real-time quantitative PCR was used to analyze the expression of serum miR-21 in 33 ISR and 37 non-ISR patients after PCI. Expression of miR-21 was significantly higher in the ISR group compared with that in the NISR group, and a similar trend also occurred in factor- (TNF-α) level, Interleukin -6 (IL-6) level, and plaque area (PLA). However, a contrary trend occurred in the external elastic membrane area (EEM) and minimal lumen area (MLA). This study suggests that the increased expression of serum miR-21 is related to ISR after PCI, and miR-21 can be a new predictor of ISR.

An Engineered Gene Nanovehicle Developed for Smart Gene Therapy to Selectively Inhibit Smooth Muscle Cells: An In Vitro Study.

In-stent restenosis is a serious concern for patients treated through the stenting procedure, although this can be solved using drug-eluting stents and/or drug-eluting balloon catheters. However, the chemical agents released from the drug-eluting layer for inhibiting smooth muscle cell (SMC) migration are inevitably associated with damage to vascular endothelial cell (ECs). The present in vitro study used a distinct strategy, in which a smart gene (phEGR1-PKCδ, an engineered plasmid consists of an SMC-specific promoter (human early growth response 1, hEGR1 promoter) ligated with a gene encoding apoptosis-inducing protein (protein kinase C-delta, PKCδ) was incorporated into a novel gene vehicle (Au cluster-incorporated polyethylenimine/carboxymethyl hexanoyl chitosan, PEI-Au/CHC) to form the PEI-Au/CHC/phEGR1-PKCδ complex, which was proposed for the selective inhibition of SMC proliferation. It was found that the cell viability of SMCs receiving the PEI-Au/CHC/phEGR1-PKCδ complex under simulated inflammation conditions was significantly lower than that of the ECs receiving the same treatment. In addition, the PEI-Au/CHC/phEGR1-PKCδ complex did not demonstrate an inhibitory effect on EC proliferation and migration under simulated inflammation conditions. Finally, the PEI-Au/CHC/phEGR1-PKCδ complexes coated onto a balloon catheter used in percutaneous transluminal coronary angioplasty (PTCA) could be transferred to both the ECs and the SMC layer of Sprague Dawley (SD) rat aortas ex vivo. These preliminary in vitro results suggest that the newly developed approach proposed in the present study might be a potential treatment for reducing the incidence rate of in-stent restenosis and late thrombosis in the future.

Myostatin Inhibits Vascular Smooth Muscle Cell Proliferation and Local 14q32 microRNA Expression, But Not Systemic Inflammation or Restenosis.

Myostatin is a negative regulator of muscle cell growth and proliferation. Furthermore, myostatin directly affects the expression of 14q32 microRNAs by binding the 14q32 locus. Direct inhibition of 14q32 microRNA miR-495-3p decreased postinterventional restenosis via inhibition of both vascular smooth muscle cell (VSMC) proliferation and local inflammation. Here, we aimed to investigate the effects of myostatin in a mouse model for postinterventional restenosis. In VSMCs in vitro, myostatin led to the dose-specific downregulation of 14q32 microRNAs miR-433-3p, miR-494-3p, and miR-495-3p. VSMC proliferation was inhibited, where cell migration and viability remained unaffected. In a murine postinterventional restenosis model, myostatin infusion did not decrease restenosis, neointimal area, or lumen stenosis. Myostatin inhibited expression of both proliferation marker PCNA and of 14q32 microRNAs miR-433-3p, miR-494-3p, and miR-495-3p dose-specifically in cuffed femoral arteries. However, 14q32 microRNA expression remained unaffected in macrophages and macrophage activation as well as macrophage influx into lesions were not decreased. In conclusion, myostatin did not affect postinterventional restenosis. Although myostatin inhibits 14q32 microRNA expression and proliferation in VSMCs, myostatin had no effect on macrophage activation and infiltration. Our findings underline that restenosis is driven by both VSMC proliferation and local inflammation. Targeting only one of these components is insufficient to prevent restenosis.

miR-196a2 (rs11614913) polymorphism is associated with coronary artery disease, but not with in-stent coronary restenosis.

OBJECTIVE: The aim of the study was to evaluate the association of miRNA-146a G/C (rs2910164), and miRNA-196a2 C/T (rs11614913) polymorphisms with the presence of coronary artery disease (CAD) and/or restenosis in patients with coronary stent. MATERIALS AND METHODS: The polymorphisms were determined in 218 patients with CAD who underwent coronary artery stenting (66 with restenosis and 152 without restenosis) and 611 healthy controls using 5' exonuclease TaqMan assays. RESULTS: The distribution of both polymorphisms was similar in patients with and without restenosis. However, when the whole group of patients (with and without restenosis) was compared to healthy controls, under co-dominant, dominant and additive genetic models, the T allele of the miRNA-196a2 C/T (rs11614913) polymorphism was associated with increased risk of CAD (OR = 2.18, Pco-dom = 0.006, OR = 1.86, Pdom = 0.002, and OR = 1.52, Padd = 0.002, respectively). All models were adjusted for age, type 2 diabetes mellitus, dyslipidemia, hypertension and smoking habit. The "GT" haplotype was associated with increased risk of developing CAD (OR = 1.36, P = 0.046). CONCLUSIONS: Our data suggests that the T allele of the miRNA-196a2 C/T (rs11614913) polymorphism is associated with the risk of developing CAD, but no association with restenosis was observed.

Relationship between ALDH2 genotype and in-stent restenosis in Chinese Han patients after percutaneous coronary intervention.

BACKGROUND: It is well known that the genotype of ALDH2 is associated with coronary artery disease (CAD), and in-stent restenosis (ISR) is a primary complication of percutaneous coronary intervention (PCI), a primary recommended treatment for CAD. The aim of this study was to identify the relationship between aldehyde dehydrogenase 2 (ALDH2) genotype and in-stent restenosis (ISR). METHODS: This study recruited 531 patients who were undergoing PCI at two Chinese hospitals from 2015 to 2017 and 183 were diagnosed with ISR after PCI during the one-year follow-up period. We used polymerase chain restriction fragment length polymorphism (PCR-RFLP) and sequencing to determine ALDH2 polymorphisms. RESULTS: Among all 531 patients (mean age = 59.4 ± 9.8; 65.9% male), 68.7% carried the wild-type genotype, 28.4% were heterozygous for the mutation, and 2.8% were homozygous for the mutation. Multiple logistical regression analyses indicated no correlation between ALDH2 genotype and the occurrence of restenosis after PCI (OR = 1.448, 95% CI: 0.965-2.168, p = 0.073), though a significant association was observed for patients with diabetes (OR = 4.053, 95% CI: 1.668-10.449, p = 0.003). CONCLUSION: In this study, we found that carrying an ALDH2*2 allele had no notable relationship with ISR one year after PCI but that it did have a significant association with complications in diabetic patients. Further studies with larger sample sizes will be necessary to reveal a consensus.

Local adventitial anti-angiogenic gene therapy reduces growth of vasa-vasorum and in-stent restenosis in WHHL rabbits.

BACKGROUND: Antiproliferative drugs in drug eluting stents (DES) are associated with complications due to impaired re-endothelialization. Additionally, adventitial neovascularization has been suggested to contribute to in-stent restenosis (ISR). Since Vascular Endothelial Growth Factors (VEGFs) are the key mediators of angiogenesis, we investigated feasibility and efficacy of local gene therapy for ISR utilizing soluble decoy VEGF receptors to reduce biological activity of adventitial VEGFs. METHOD: Sixty-nine adult WHHL rabbit aortas were subjected to endothelial denudation. Six weeks later catheter-mediated local intramural infusion of 1.5x10e10 pfu adenoviruses encoding soluble VEGF Receptor-1 (sVEGFR1), sVEGFR2, sVEGFR3 or control LacZ and bare metal stent implantation were performed in the same aortic segment. Marker protein expression was assessed at 6d in LacZ cohort. Immunohistochemistry, morphometrical analyses and angiography were performed at d14, d42 and d90. RESULTS: Transgene expression was localized to adventitia. All decoy receptors reduced the size of vasa-vasorum at 14d, AdsVEGFR2 animals also had reduced density of adventitial vasa-vasorum, whereas AdsVEGFR3 increased the density of vasa-vasorum. At d42, AdsVEGFR1 and AdsVEGFR2 reduced ISR (15.7 ±â€¯6.9% stenosis, P < 0.01 and 16.5 ±â€¯2.7%, P < 0.05, respectively) vs. controls (28.3 ±â€¯7.6%). Moreover, AdsVEGFR-3 treatment led to a non-significant trend in the reduction of adventitial lymphatics at all time points and these animals had significantly more advanced neointimal atherosclerosis at 14d and 42d vs. control animals. CONCLUSIONS: Targeting adventitial neovascularization using sVEGFR1 and sVEGFR2 is a novel strategy to reduce ISR. The therapeutic effects dissipate at late follow up following short expression profile of adenoviral vectors. However, inhibition of VEGFR3 signaling accelerates neoatherosclerosis.

Inhibition of DNA methyltransferase-1 instigates the expression of DNA methyltransferase-3a in angioplasty-induced restenosis.

Increased expression of DNA methyltransferase-1 (DNMT1) associates with the progression of many human diseases. Because DNMT1 induces cell proliferation, drugs that inhibit DNMT1 have been used to treat proliferative diseases. Because these drugs are nonspecific inhibitors of DNMT1, subsidiary events or the compensatory mechanisms that are activated in the absence of DNMT1 limit their therapeutic application. Here, we studied the molecular mechanisms that occur during angioplasty-induced restenosis and found that DNMT1 inhibition in both in vitro and in vivo approaches resulted in the induction of DNA methyltransferase-3a (DNMT3a) expression. In vascular smooth muscle cells (VSMCs), the microRNA hsa-miR-1264 mimic, specifically inhibiting DNMT1, induced nuclear expression of DNMT3a. On the contrary, there was no induced expression of DNMT3a in VSMCs that were transfected with hsa-miR-1264 inhibitor. Further, ectopic expression of suppressor of cytokine signaling 3 (SOCS3) through adeno-associated virus (AAV)-mediated gene delivery in the coronary arteries of Yucatan microswine showed inhibition of both DNMT1 and DNMT3a in vivo. These findings show the existence of an inter-regulatory mechanism between DNMT1 and DNMT3a where, in the absence of DNMT1, induction of DNMT3a compensates for the loss of DNMT1 functions, suggesting that the inhibition of both DNMT1 and DNMT3a are required to prevent restenosis.

Fufang-Zhenzhu-Tiaozhi Capsule reduces restenosis via the downregulation of NF-kappaB and inflammatory factors in rabbits.

BACKGROUND: To investigate the effects of a Chinese herbal medicine Fufang-Zhenzhu Tiaozhi Capsule (FTZ) on restenosis and elucidate the mechanism of action. METHODS: A restenosis model was established by balloon rubbing the endothelium of the abdominal aorta followed by high fat diet. Rabbits were divided into blank control group, restenosis group, FTZ group (0.66 mg/kg/day), atorvastatin group (5 mg/kg/day) and FTZ + atorvastatin group (n = 8). Vascular stenosis was analyzed by X-ray. Serum levels of chemokines and cytokines interleukin-1 (IL-1), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-12 (IL-12), C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1) were measured by ELISA. The levels of NF-κB, IκB-α, P-IκBα, IKK-α, and P-IKKα/ß from injured abdominal arteries were detected by Western blotting. RESULTS: Restenosis was induced successfully via abdominal artery balloon injuries and high fat diet. Restenosis was significantly decreased in FTZ group compared with restenosis group (P < 0.05). FTZ group had markedly reduced serum lipid levels (P < 0.05). In addition, the levels of TNF-α, IL-1, IL-6, IL-8, IL-12, ICAM-1 and MCP-1 decreased by FTZ treatment (P < 0.05). The expression of NF-κB in the atherosclerotic lesions was significantly attenuated in FTZ group (P < 0.05). CONCLUSION: FTZ could reduce restenosis via reducing NF-κB activity and inflammatory factor expression within the atherosclerotic lesion in a rabbit restenosis model. FTZ may be a new therapeutic agent for restenosis.

Role of Gene Polymorphisms/Haplotypes and Plasma Level of TGF-ß1 in Susceptibility to In-Stent Restenosis Following Coronary Implantation of Bare Metal Stent in Chinese Han Patients.

Transforming growth factor (TGF)-ß1 has been implicated in the pathogenesis of restenosis. However, the role of TGF-ß1 polymorphisms in development of in-stent restenosis (ISR) after coronary bare metal stent (BMS) implantation in Chinese Han population has not been reported to date. The aim of this study was to explore the association between TGF-ß1 gene polymorphisms (-509C/T and 869T/C) and its plasma level in Chinese Han patients with BMS-ISR.We investigated 419 patients after successful coronary stent placement. All patients were reexamined by angiography. Genotyping for the two TGF-ß1 gene polymorphisms was performed using polymerase chain reaction-restriction fragment length polymorphism analysis. Plasma TGF-ß1 levels were measured by enzyme-linked immunosorbent assay.Ninety-two patients (21.96%) developed ISR during the follow-up period. The multivariable analysis adjusted for potential confounders and it revealed that the C allele of TGF-ß1 869T/C polymorphism was linked to an increased risk of ISR in both additive (Per each C allele) and dominant (TC+CC versus TT) models with odds ratios (ORs) of 1.88 (95% confidence interval [CI]: 1.21-2.84, P = 0.008) and 2.52 (95% CI: 1.40-4.80, P = 0.005), respectively. In accord with this, C-dominant CC/CT genotype was linked to higher plasma TGF-ß1 level compared to TT genotype. One haplotype (TC) (-509T, +869C) was associated with an increased risk for ISR (OR = 1.48, 95% CI: 1.06-2.06, P = 0.010).The C allele of TGF-ß1 869T/C polymorphism, correlated with high plasma TGF-ß1 level, represented an independent risk factor for BMS-ISR in Chinese Han patients with coronary artery disease.

Stent-mediated gene and drug delivery for cardiovascular disease and cancer: A brief insight.

This review concisely recapitulates the different existing modes of stent-mediated gene/drug delivery, their considerable advancement in clinical trials and a rationale for other merging new technologies such as nanotechnology and microRNA-based therapeutics, in addition to addressing the limitations in each of these perpetual stent platforms. Over the past decade, stent-mediated gene/drug delivery has materialized as a hopeful alternative for cardiovascular disease and cancer in contrast to routine conventional treatment modalities. Regardless of the phenomenal recent developments achieved by coronary interventions and cancer therapies that employ gene and drug-eluting stents, practical hurdles still remain a challenge. The present review highlights the limitations that each of the existing stent-based gene/drug delivery system encompasses and therefore provides a vision for the future with respect to discovering an ideal stent therapeutic platform that would circumvent all the practical hurdles witnessed with the existing technology. Further study of the improvisation of next-generation drug-eluting stents has helped to overcome the issue of restenosis to some extent. However, current stent formulations fall short of the anticipated clinically meaningful outcomes and there is an explicit need for more randomized trials aiming to further evaluate stent platforms in favour of enhanced safety and clinical value. Gene-eluting stents may hold promise in contributing new ideas for stent-based prevention of in-stent restenosis through genetic interventions by capitalizing on a wide variety of molecular targets. Therefore, the central consideration directs us toward finding an ideal stent therapeutic platform that would tackle all of the gaps in the existing technology.

Genetic risk factors for restenosis after percutaneous coronary intervention in Kazakh population.

BACKGROUND: After coronary stenting, the risk of developing restenosis is from 20 to 35 %. The aim of the present study is to investigate the association of genetic variation in candidate genes in patients diagnosed with restenosis in the Kazakh population. METHODS: Four hundred fifty-nine patients were recruited to the study; 91 patients were also diagnosed with diabetes and were excluded from the sampling. DNA was extracted with the salting-out method. The patients were genotyped for 53 single-nucleotide polymorphisms. Genotyping was performed on the QuantStudio 12K Flex (Life Technologies). Differences in distribution of BMI score among different genotype groups were compared by analysis of variance (ANOVA). Also, statistical analysis was performed using R and PLINK v.1.07. Haplotype frequencies and LD measures were estimated by using the software Haploview 4.2. RESULTS: A logistic regression analysis found a significant difference in restenosis rates for different genotypes. FGB (rs1800790) is significantly associated with restenosis after stenting (OR = 2.924, P = 2.3E-06, additive model) in the Kazakh population. CD14 (rs2569190) showed a significant association in the additive (OR = 0.08033, P = 2.11E-09) and dominant models (OR = 0.05359, P = 4.15E-11). NOS3 (rs1799983) was also highly associated with development of restenosis after stenting in additive (OR = 20.05, P = 2.74 E-12) and recessive models (OR = 22.24, P = 6.811E-10). CONCLUSIONS: Our results indicate that FGB (rs1800790), CD14 (rs2569190), and NOS3 (rs1799983) SNPs could be genetic markers for development of restenosis in Kazakh population. Adjustment for potential confounder factor BMI gave almost the same results.