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Intimal hyperplasia (IH) is an innegligible issue for patients undergoing interventional therapy. The proliferation and migration of vascular smooth muscle cells (VSMCs) induced by platelet-derived growth factor-BB (PDGF-BB) are critical events in the development of IH. While the exact mechanism and effective target for IH needs further investigation. Metabolic disorders of arachidonic acid (ARA) are involved in the occurrence and progression of various diseases. In this study, we found that the expressions of soluble epoxide hydrolase (sEH) and cyclooxygenase-2 (COX-2) were significantly increased in the VSMCs during balloon injury-induced IH. Then, we employed a COX-2/sEH dual inhibitor PTUPB to increase the concentration of epoxyeicosatrienoic acids (EETs) while prevent the release of pro-inflammatory prostaglandins. Results showed that PTUPB treatment significantly reduced neointimal thickening induced by balloon injury in rats in vivo and inhibited PDGF-BB-induced proliferation and migration of VSMCs in vitro. Our results showed that PTUPB may reverse the phenotypic transition of VSMCs by inhibiting Pttg1 expression. In conclusion, we found that the dysfunction of ARA metabolism in VSMCs contributes to IH, and the COX-2/sEH dual inhibitor PTUPB attenuates IH progression by reversing the phenotypic switch in VSMC through the Sirt1/Pttg1 pathway., Competing Interests: Declaration of competing interest We would like to submit the enclosed manuscript entitled “Restoration of ARA metabolic disorders in vascular smooth muscle cells alleviates intimal hyperplasia”, which we wish to be considered for publication in “European Journal of Pharmacology”. I would like to declare on behalf of my co-authors that:, (Copyright © 2024 Elsevier B.V. All rights reserved.)

The proliferative and migratory abilities of vascular smooth muscle cells (VSMCs) play a crucial role in neointima formation following vascular injury. Skp2 facilitates proliferation and migration in cells through cell cycle regulation, presenting an important therapeutic target for atherosclerosis, pulmonary hypertension, and vascular restenosis. This study aimed to identify a natural product capable of inhibiting neointima formation post vascular injury. Here, we demonstrate that troxerutin, a flavonoid, significantly reduced viability and downregulated Skp2 in VSMCs. Moreover, troxerutin exhibited anti-proliferative effects on VSMCs and mitigated neointima formation. These findings collectively elucidate the intrinsic mechanism of troxerutin in treating atherosclerosis, pulmonary hypertension, and vascular restenosis by targeting the E3-linked enzyme Skp2., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Kawasaki disease (KD) causes vascular injury and lifelong remodeling. Excessive intimal proliferation has been observed, resulting in coronary artery lesions (CALs). However, the mechanisms underlying vascular remodeling in CAL and statin treatment have not been comprehensively elucidated. This study aimed to investigate the effects of statins on vascular remodeling using a KD mouse model. Candida albicans water-soluble substance (CAWS) was intraperitoneally injected in 5-week-old male apolipoprotein-E-deficient mice. They were categorized as follows (n = 4): control, CAWS, CAWS+statin, and late-statin groups. The mice were euthanized at 6 or 10 weeks after injection. Statins (atorvastatin) were initiated after CAWS injection, except for the late-statin group, for which statins were internally administered 6 weeks after injection. Elastica van Gieson staining and immunostaining were performed for evaluation. Statins substantially suppressed the marked neointimal hyperplasia induced by CAWS. Additionally, CAWS induced TGFβ receptor II and MAC-2 expression around the coronary arteries, which was suppressed by the statins. KD-like vasculitis might promote the formation of aneurysm by destroying elastic laminae and inducing vascular stenosis by neointimal proliferation. The anti-inflammatory effects of statins might inhibit neointimal proliferation. Therefore, statin therapy might be effective in adult patients with KD with CAL by inhibiting vascular remodeling., (© 2024 The Author(s). Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Background: Restenosis frequently occurs after percutaneous angioplasty in patients with vascular occlusion and seriously threatens their health. Substantial evidence has revealed that preventing vascular smooth muscle cell proliferation using a drug-eluting stent is an effective approach to improve restenosis. Cucurbitacins have been demonstrated to exert an anti-proliferation effect in various tumors and a hypotensive effect. This study aims to investigate the role of cucurbitacins extracted from Cucumis melo L. (CuECs) and cucurbitacin B (CuB) on restenosis., Methods: C57BL/6 mice were subjected to left carotid artery ligation and subcutaneously injected with CuECs or CuB for 4 weeks. Hematoxylin-Eosin, immunofluorescence and immunohistochemistry staining were used to evaluate the effect of CuECs and CuB on neointimal hyperplasia. Western blot, real-time PCR, flow cytometry analysis, EdU staining and cellular immunofluorescence assay were employed to measure the effects of CuECs and CuB on cell proliferation and the cell cycle in vitro. The potential interactions of CuECs with cyclin A2 were performed by molecular docking., Results: The results demonstrated that both CuECs and CuB exhibited significant inhibitory effects on neointimal hyperplasia and proliferation of vascular smooth muscle cells. Furthermore, CuECs and CuB mediated cell cycle arrest at the S phase. Autodocking analysis demonstrated that CuB, CuD, CuE and CuI had high binding energy for cyclin A2. Our study also showed that CuECs and CuB dramatically inhibited FBS-induced cyclin A2 expression. Moreover, the expression of cyclin A2 in CuEC- and CuB-treated neointima was downregulated., Conclusions: CuECs, especially CuB, exert an anti-proliferation effect in VSMCs and may be potential drugs to prevent restenosis., (© 2024 The Author(s). Animal Models and Experimental Medicine published by John Wiley & Sons Australia, Ltd on behalf of The Chinese Association for Laboratory Animal Sciences.)

Background: Dysregulation of vascular smooth muscle cell (VSMC) function leads to a variety of diseases such as atherosclerosis and hyperplasia after injury. However, antiproliferative drug targeting VSMC exhibits poor specificity. Therefore, there is an urgent to develop highly specific antiproliferative drugs to prevention and treatment VSMC dedifferentiation associated arteriosclerosis. Kanglexin (KLX), a new anthraquinone compound designed by our team, has potential to regulate VSMC phenotype according to the physicochemical properties., Purpose: This project aims to evaluate the therapeutic role of KLX in VSMC dedifferentiation and atherosclerosis, neointimal formation and illustrates the underlying molecular mechanism., Methods: In vivo, the ApoE -/- mice were fed with high-fat diet (HFD) for a duration of 13 weeks to establish the atherosclerotic model. And rat carotid artery injury model was performed to establish the neointimal formation model. In vitro, PDGF-BB was used to induce VSMC dedifferentiation., Results: We found that KLX ameliorated the atherosclerotic progression including atherosclerotic lesion formation, lipid deposition and collagen deposition in aorta and aortic sinus in atherosclerotic mouse model. In addition, The administration of KLX effectively ameliorated neointimal formation in the carotid artery following balloon injury in SD rats. The findings derived from molecular docking and surface plasmon resonance (SPR) experiments unequivocally demonstrate that KLX had potential to bind PDGFR-β. Mechanism research work proved that KLX prevented VSMC proliferation, migration and dedifferentiation via activating the PDGFR-β-MEK -ERK-ELK-1/KLF4 signaling pathway., Conclusion: Collectively, we demonstrated that KLX effectively attenuated the progression of atherosclerosis in ApoE-/- mice and carotid arterial neointimal formation in SD rats by inhibiting VSMC phenotypic conversion via PDGFR-β-MEK-ERK-ELK-1/KLF4 signaling. KLX exhibits promising potential as a viable therapeutic agent for the treatment of VSMC phenotype conversion associated arteriosclerosis., Competing Interests: Declaration of competing interest All authors disclosed no relevant relationships., (Copyright © 2024. Published by Elsevier GmbH.)

Background: Vascular smooth muscle cell (VSMC) proliferation and phenotypic switching are key mechanisms in the development of proliferative arterial diseases. Notably, reprogramming of the glucose metabolism pattern in VSMCs plays an important role in this process., Purpose: The aim of this study is to investigate the therapeutic potential and the mechanism underlying the effect of bergenin, an active compound found in Bergenia, in proliferative arterial diseases., Methods: The effect of bergenin on proliferative arterial disease was evaluated using platelet-derived growth factor (PDGF)-stimulated VSMCs and a mouse model of carotid artery ligation. VSMC proliferation and phenotypic switching were evaluated in vitro using cell counting kit-8, 5-ethynyl-2-deoxyuridine incorporation, scratch, and transwell assays. Carotid artery neointimal hyperplasia was evaluated in vivo using hematoxylin and eosin staining and immunofluorescence. The expression of proliferation and VSMC contractile phenotype markers was evaluated using PCR and western blotting., Results: Bergenin treatment inhibited PDGF-induced VSMC proliferation and phenotypic switching and reduced neointimal hyperplasia in the carotid artery ligation model. Additionally, bergenin partially reversed the PDGF-induced Warburg-like glucose metabolism pattern in VSMCs. RNA-sequencing data revealed that bergenin treatment significantly upregulated Ndufs2, an essential subunit of mitochondrial complex I. Ndufs2 knockdown attenuated the inhibitory effect of bergenin on PDGF-induced VSMC proliferation and phenotypic switching, and suppressed neointimal hyperplasia in vivo. Conversely, Ndufs2 overexpression enhanced the protective effect of bergenin. Moreover, Ndufs2 knockdown abrogated the effects of bergenin on the regulation of glucose metabolism in VSMCs., Conclusion: These findings suggest that bergenin is effective in alleviating proliferative arterial diseases. The reversal of the Warburg-like glucose metabolism pattern in VSMCs during proliferation and phenotypic switching may underlie this therapeutic mechanism., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier GmbH.)

Neointimal hyperplasia is the main cause of vascular graft failure in the medium term. Vitamin D receptor activation modulates the biology of vascular smooth muscle cells and has been reported to protect from neointimal hyperplasia following endothelial injury. However, the molecular mechanisms are poorly understood. We have now explored the impact of the selective vitamin D receptor activator, paricalcitol, on neointimal hyperplasia, following guidewire-induced endothelial cell injury in rats, and we have assessed the impact of paricalcitol or vehicle on the expression of key cell stress factors. Guidewire-induced endothelial cell injury caused neointimal hyperplasia and luminal stenosis and upregulated the expression of the growth factor growth/differentiation factor-15 (GDF-15), the cytokine receptor CD74, NFκB-inducing kinase (NIK, an upstream regulator of the proinflammatory transcription factor NFκB) and the chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2). Immunohistochemistry confirmed the increased expression of the cellular proteins CD74 and NIK. Paricalcitol (administered in doses of 750 ng/kg of body weight, every other day) had a non-significant impact on neointimal hyperplasia and luminal stenosis. However, it significantly decreased GDF-15, CD74, NIK and MCP-1/CCL2 mRNA expression, which in paricalcitol-injured arteries remained within the levels found in control vehicle sham arteries. In conclusion, paricalcitol had a dramatic effect, suppressing the stress response to guidewire-induced endothelial cell injury, despite a limited impact on neointimal hyperplasia and luminal stenosis. This observation identifies novel molecular targets of paricalcitol in the vascular system, whose differential expression cannot be justified as a consequence of improved tissue injury.

The abnormal proliferation, migration, and inflammation of vascular smooth muscle cells (VSMCs) play crucial roles in the development of neointimal hyperplasia and restenosis. Exposure to inflammatory cytokines such as platelet-derived growth factor (PDGF)-BB and tumour necrosis factor-alpha (TNF-α) induces the transformation of contractile VSMCs into abnormal synthetic VSMCs. Isoxanthohumol (IXN) has significant anti-inflammatory, antiproliferative, and antimigratory effects. This study aimed to explore the therapeutic impact and regulatory mechanism of IXN in treating neointimal hyperplasia. The present findings indicate that IXN effectively hinders the abnormal proliferation, migration, and inflammation of VSMCs triggered by PDGF or TNF-α. This inhibition is primarily achieved through the modulation of the apelin/AKT or AKT pathway, respectively. In an in vivo model, IXN effectively reduced neointimal hyperplasia in denuded femoral arteries. These results suggest that IXN holds promise as a potential and innovative therapeutic candidate for the treatment of restenosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Restenosis after angioplasty is caused usually by neointima formation characterized by aberrant vascular smooth muscle cell (VSMC) dedifferentiation. Myeloid-derived growth factor (MYDGF), secreted from bone marrow-derived monocytes and macrophages, has been found to have cardioprotective effects. In this study we investigated the effect of MYDGF to postinjury neointimal formation and the underlying mechanisms. Rat carotid arteries balloon-injured model was established. We found that plasma MYDGF content and the level of MYDGF in injured arteries were significantly decreased after balloon injury. Local application of exogenous MYDGF (50 μg/mL) around the injured vessel during balloon injury markedly ameliorated the development of neointimal formation evidenced by relieving the narrow endovascular diameter, improving hemodynamics, and reducing collagen deposition. In addition, local application of MYDGF inhibited VSMC dedifferentiation, which was proved by reversing the elevated levels of osteopontin (OPN) protein and decreased levels of α-smooth muscle actin (α-SMA) in the left carotid arteries. We showed that PDGF-BB (30 ng/mL) stimulated VSMC proliferation, migration and dedifferentiation in vitro; pretreatment with MYDGF (50-200 ng/mL) concentration-dependently eliminated PDGF-BB-induced cell proliferation, migration and dedifferentiation. Molecular docking revealed that MYDGF had the potential to bind with sphingosine-1-phosphate receptor 2 (S1PR2), which was confirmed by SPR assay and Co-IP analysis. Pretreatment with CCG-1423 (Rho signaling inhibitor), JTE-013 (S1PR2 antagonist) or Ripasudil (ROCK inhibitor) circumvented the inhibitory effects of MYDGF on VSMC phenotypic switching through inhibiting S1PR2 or its downstream RhoA-actin monomers (G-actin) /actin filaments (F-actin)-MRTF-A signaling. In summary, this study proves that MYDGF relieves neointimal formation of carotid arteries in response to balloon injury in rats, and suppresses VSMC dedifferentiation induced by PDGF-BB via S1PR2-RhoA-G/F-actin-MRTF-A signaling pathway. In addition, our results provide evidence for cross talk between bone marrow and vasculature., (© 2023. The Author(s), under exclusive licence to Shanghai Institute of Materia Medica, Chinese Academy of Sciences and Chinese Pharmacological Society.)

Introduction: Arterial restenosis caused by intimal hyperplasia (IH) is a serious complication after vascular interventions. In the rat carotid balloon injury model, we injected phosphate buffer saline (PBS), rapamycin-phosphate buffer saline suspension (RPM-PBS), blank fibrin glue (FG) and rapamycin-fibrin glue (RPM-FG) around the injured carotid artery under ultrasound guidance and observed the inhibitory effect on IH., Methods: The properties of RPM-FG in vitro were verified by scanning electron microscopy (SEM) and determination of the drug release rate. FG metabolism in vivo was observed by fluorescence imaging. The rat carotid balloon injury models were randomly classified into 4 groups: PBS group (control group), RPM-PBS group, FG group, and RPM-FG group. Periadventitial administration was performed by ultrasound-guided percutaneous puncture on the first day after angioplasty. Carotid artery specimens were analyzed by immunostaining, Evans blue staining and hematoxylin-eosin staining., Results: The RPM particles showed clustered distributions in the FG block. The glue was maintained for a longer time in vivo (> 14 days) than in vitro (approximately 7 days). Two-component liquid FG administered by ultrasound-guided injection completely encapsulated the injured artery before coagulation. The RPM-FG inhibited IH after carotid angioplasty vs. control and other groups. The proliferation of vascular smooth muscle cells (VSMCs) was significantly inhibited during neointima formation, whereas endothelial cell (EC) repair was not affected., Conclusion: Periadventitial delivery of RPM-FG contributed to inhibiting IH in the rat carotid artery injury model without compromising re-endothelialization. Additionally, FG provided a promising platform for the future development of a safe, effective, and minimally invasive perivascular drug delivery method to treat vascular disease., Competing Interests: Declaration of Competing Interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2023. Published by Elsevier B.V.)

Objective: Neointimal hyperplasia is the primary mechanism underlying atherosclerosis and restenosis after percutaneous coronary intervention. Ketogenic diet (KD) exerts beneficial effects in various diseases, but whether it could serve as non-drug therapy for neointimal hyperplasia remains unknown. This study aimed to investigate the effect of KD on neointimal hyperplasia and the potential mechanisms., Methods and Results: Carotid artery balloon-injury model was employed in adult Sprague-Dawley rats to induce neointimal hyperplasia. Then, animals were subjected to either standard rodent chow or KD. For in-vitro experiment, impacts of β-hydroxybutyrate (β-HB), the main mediator of KD effects, on platelet-derived growth factor BB (PDGF-BB) induced vascular smooth muscle cell (VSMC) migration and proliferation were determined. Balloon injury induced event intimal hyperplasia and upregulation of protein expression of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA), and these changes were significantly ameliorated by KD. In addition, β-HB could markedly inhibit PDGF-BB induced VMSC migration and proliferation, as well as inhibiting expressions of PCNA and α-SMC. Furthermore, KD inhibited balloon-injury induced oxidative stress in carotid artery, indicated by reduced ROS level, malondialdehyde (MDA) and myeloperoxidase (MPO) activities, and increased superoxide dismutase (SOD) activity. We also found balloon-injury induced inflammation in carotid artery was suppressed by KD, indicated by decreased expressions of proinflammatory cytokines IL-1β and TNF-α, and increased expression of anti-inflammatory cytokine IL-10., Conclusion: KD attenuates neointimal hyperplasia through suppressing oxidative stress and inflammation to inhibit VSMC proliferation and migration. KD may represent a promising non-drug therapy for neointimal hyperplasia associated diseases.

High-density lipoprotein (HDL) therapy has demonstrated beneficial effects in acute stroke and acute myocardial infarction models by reducing infarct size. In this study, we investigated the inhibitory effects of reconstituted HDL (rHDL) on neointimal hyperplasia and elucidated its underlying mechanism using a balloon injury rat model. Our finding revealed a significant 37% reduction in the intima to media ratio in the arteries treated with 80 mg/kg rHDL compared to those subjected to injury alone (p < 0.05), indicating a specific inhibition of neointimal hyperplasia. In vivo analysis further supported the positive effects of rHDL by demonstrating a reduction in smooth muscle cell (SMC) proliferation and an increase in endothelial cell (EC) proliferation. Additionally, rHDL treatment led to decreased infiltration of leukocytes and downregulated the expression of matrix metallopeptidase 9 (MMP9) in the neointimal area. Notably, rHDL administration resulted in decreased expression of VCAM1 and HIF1α, alongside increased expression of heme oxygenase 1 (HO1) and heat shock protein 27 (HSP27). Overexpression of HSP27 and HO1 effectively inhibited SMC proliferation. Moreover, rHDL-mediated suppression of injury-induced HIF1α coincided with upregulation of HSP27. Interestingly, HSP27 and HO1 had varying effects on the expression of chemokine receptors and rHDL did not exert significant effect on chemokine receptor expression in THP1 cells. These findings underscore the distinct roles of HSP27 and HO1 as potential regulatory factors in the progression of restenosis. Collectively, our study demonstrates that rHDL exerts a potent anti-neointimal hyperplasia effect by reducing leukocytes infiltration and SMC proliferation while promoting EC proliferation., (© 2023. The Author(s).)

Autophagy inducers can prevent cardiovascular aging and age-associated diseases including atherosclerosis. Therefore, we hypothesized that autophagy-inducing compounds that act on atherosclerosis-relevant cells might have a protective role in the development of atherosclerosis. Here we identified 3,4-dimethoxychalcone (3,4-DC) as an inducer of autophagy in several cell lines from endothelial, myocardial and myeloid/macrophagic origin, as demonstrated by the aggregation of the autophagosome marker GFP-LC3 in the cytoplasm of cells, as well as the downregulation of its nuclear pool indicative of autophagic flux. In this respect, 3,4-DC showed a broader autophagy-inducing activity than another chalcone (4,4- dimethoxychalcone), spermidine and triethylene tetramine. Thus, we characterized the potential antiatherogenic activity of 3,4-DC in two different mouse models, namely, (i) neointima formation with smooth muscle expansion of vein segments grafted to the carotid artery and (ii) genetically predisposed ApoE -/- mice fed an atherogenic diet. In the vein graft model, local application of 3,4-DC was able to maintain the lumen of vessels and to reduce neointima lesions. In the diet-induced model, intraperitoneal injections of 3,4-DC significantly reduced the number of atherosclerotic lesions in the aorta. In conclusion, 3,4-DC stands out as an autophagy inducer with potent antiatherogenic activity., (© 2023. The Author(s).)

Open vascular reconstructions such as bypass are common treatments for cardiovascular disease. Unfortunately, neointimal hyperplasia (IH) follows, leading to treatment failure for which there is no approved therapy. Here we combined the strengths of tailoring nanoplatforms for open vascular reconstructions and targeting new epigenetic mechanisms. We produced adhesive nanoparticles (ahNP) that could be pen-brushed and immobilized on the adventitia to sustainably release pinometostat, an inhibitor drug selective to the epigenetic writer DOT1L that catalyzes histone-3 lysine-79 dimethylation (H3K79me2). This treatment not only reduced IH by 76.8% in injured arteries mimicking open reconstructions in obese Zucker rats with human-like diseases but also avoided the shortcoming of endothelial impairment in IH management. In mechanistic studies, chromatin immunoprecipitation (ChIP) sequencing revealed co-enrichment of the histone mark H3K27ac(acetyl) and its reader BRD4 at the gene of aurora kinase B (AURKB), where H3K79me2 was also enriched as indicated by ChIP-qPCR. Accordingly, DOT1L co-immunoprecipitated with H3K27ac. Furthermore, the known IH driver BRD4 governed the expression of DOT1L which controlled AURKB's protein level, revealing a BRD4- > DOT1L- > AURKB axis. Consistently, AURKB-selective inhibition reduced IH. Thus, this study presents a prototype nanoformulation suited for open vascular reconstructions, and the new insights into chromatin modulators may aid future translational advances., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Objective: To investigate whether empagliflozin could prevent injury-induced vascular neointimal hyperplasia and to further explore its mechanism., Methods: Male C57BL/6J mice were divided into two groups with or without the empagliflozin treatment, and carotid ligation injury was performed to induce neointimal hyperplasia. The injured carotid arteries were collected for Western blotting (WB), histology and immunofluorescence analysis after four weeks. The inflammatory responses were analyzed by qRT-PCR to detect the inflammatory gene mRNA expression. To further explore its mechanism, HUVECs were treated with TGFβ-1 to induce EndMT followed by empagliflozin or vehicle treatment in vitro. A23187 (Calcimycin), an agonist of NF-κB signaling was used in the experiment., Results: The wall thickness and the neointima area was significantly reduced in the empagliflozin treatment group on day 28 after artery ligation. The Ki-67 positive cells were 28.33 ± 12.66% and 48.83 ± 10.41% in the empagliflozin-treated group and control group, respectively (P < 0.05). The mRNA expression levels of the inflammatory genes and inflammatory cells were decreased in the empagliflozin treatment group, as well as the MMP2 and MMP9. Meanwhile, empagliflozin can significantly reduce the migratory ability of inflammatory-treated HUVECs. The CD31 was increased in the TGFβ1+empagliflozin group, whereas the FSP-1, phosphorylation of TAK-1 (p-TAK-1) and phosphorylation of NF-κB (p- NF-κB) expression level were decreased, compared to the control group without empagliflozin treatment. However, the expression level of FSP-1 and p-NF-κB were reversed after co-treatment with A23187, whereas the p-TAK-1 expression level was without any significant difference., Conclusion: Empagliflozin inhibits the inflammation-induced EndMT via the TAK-1/NF-κB signaling pathway., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Vascular smooth muscle cells (VSMCs) proliferation, migration, and phenotypic switching are considered crucial events in the progression of neointima formation. Stimulator of interferon genes (STING), an innate immune sensor of cyclic dinucleotides against pathogens, in neointima formation remains obscure. Here, we observed a significant increase in STING expression on the neointima of injured vessels and mouse aortic VSMCs induced by PDGF-BB. In vivo, global knockout of STING (Sting -/- ) attenuated neointima formation after vascular injury. In vitro data showed that STING deficiency significantly alleviated PDGF-BB-induced proliferation and migration in VSMCs. Furthermore, these contractile marker genes were upregulated in Sting -/- VSMCs. Overexpression of STING promoted proliferation, migration, and phenotypic switching in VSMCs. Mechanistically, STING-NF-κB signaling was involved in this process. The pharmacological inhibition of STING induced by C-176 partially prevented neointima formation due to suppression of VSMCs proliferation. Taken together, STING-NF-κB axis significantly promoted proliferation, migration, and phenotypic switching of VSMCs, which may be a novel therapeutic approach to combat vascular proliferative diseases., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Neointimal hyperplasia is a persistent complication after vascular interventions, and it is also the leading cause of vascular graft restenosis and failure after arterial interventions, so novel treatment methods are needed to treat this complication. We hypothesized that adventitial injection of HA/SA hydrogel loaded with PLGA rapamycin nanoparticle (hydrogel-PLGA-rapamycin) could inhibit neointimal hyperplasia in a rat aortic wire injury model. The HA/SA hydrogel was fabricated by the interaction of hyaluronic acid (HA), sodium alginate (SA), and CaCO 3 ; and loaded with PLGA rapamycin nanoparticle or rhodamine uniformly. A SD rat aortic wire injury induced neointimal hyperplasia model was developed, the control group only received wire injury, the adventitial application group received 10 μL hydrogel-PLGA-rapamycin after wire injury, and the adventitial injection group received 10 μL hydrogel-PLGA-rapamycin injected into the aortic adventitia after wire injury. Tissues were harvested at day 21 and analyzed by histology and immunohistochemical staining. Hydrogel loaded with rhodamine can be successfully injected into the aortic adventitia and was encapsuled by the adventitia. The hydrogel could be seen beneath the adventitia after adventitial injection but was almost degraded at day 21. There was a significantly thinner neointima in the adventitial application group and adventitial injection group compared to the control group (p = 0.0009). There were also significantly fewer CD68 + (macrophages) cells (p = 0.0012), CD3 + (lymphocytes) cells (p = 0.0011), p-mTOR + cells (p = 0.0019), PCNA + cells (p = 0.0028) in the adventitial application and adventitial injection groups compared to the control group. The endothelial cells expressed arterial identity markers (Ephrin-B2 and dll-4) in all these three groups. Adventitial injection of hydrogel-PLGA-rapamycin can effectively inhibit neointimal hyperplasia after rat aortic wire injury. This may be a promising drug delivery method and therapeutic choice to inhibit neointimal hyperplasia after vascular interventions., (© 2022. Controlled Release Society.)

Aims : The proliferation and migration of vascular smooth muscle cells (VSMCs) play vital roles in the pathological process of neointima formation after vascular injury. Galangin, an extract of the ginger plant galangal, is involved in numerous biological activities, including inhibiting the proliferation and migration of tumor cells, but its effect on VSMCs is unknown. This study focused on the role and mechanism of galangin in the neointima formation induced by vascular injury. Methods and results : In this study, we found that galangin restrained the PDGF-BB-induced proliferation, migration and phenotypic switching of VSMCs in a concentration-dependent manner. In vivo , we established a model of carotid artery balloon injury in rats, followed by intragastric administration of galangin (40 mg kg -1 day -1 or 80 mg kg -1 day -1 ) for 14 or 28 consecutive days. Then, the degree of neointima hyperplasia was evaluated by H&E staining, and the level of relevant protein expression was assessed by immunofluorescence and western blotting. In vitro , we isolated and grew primary rat aortic smooth muscle cells, which were treated with PDGF-BB and different doses of galangin, and then CCK-8 assay, wound healing assay, transwell assay, western blotting and immunofluorescence assays were performed. We found that galangin significantly inhibited PDGF-BB-induced proliferation, migration, and phenotypic switching of VSMCs and promoted autophagy in VSMCs in vitro , and galangin significantly inhibited neointimal hyperplasia after the common carotid artery balloon injury in rats. In terms of mechanisms, galangin inhibited the PI3K/AKT/mTOR pathway, thereby suppressing VSMC's switch from a contractile to a synthetic phenotype, inhibiting VSMC proliferation, migration and phenotypic switching and upregulating the Beclin1 protein expression levels and the ratio of LC3BII/I, promoting VSMC autophagy, and thereby inhibiting neointimal hyperplasia after vascular injury. Conclusion : Our study suggests that galangin inhibits neointimal hyperplasia after vascular injury by inhibiting smooth muscle cell proliferation, migration and phenotypic switching and by promoting autophagy, and that galangin may be a promising drug for the prevention and treatment of vascular restenosis after PCI.

Restenosis induced by neointimal hyperplasia is one of the key reasons limiting the long-term success of cardiovascular interventional therapy. However, it remains a serious challenge to completely overcome restenosis because of the dilemma of simultaneously activating human umbilical vein endothelial cells (HUVECs) and inhibiting human aortic smooth muscle cells (HASMCs). Herein, we developed a targeted nanomedicine encapsulating the liver X receptor (LXR) agonist, T0901317, for differentially regulating the behaviors of HUVECs and HASMCs. The stimulatory effect on HUVEC proliferation/migration and the inhibitory effect on HASMC proliferation/migration were confirmed in vitro , respectively. In the co-culture system, the competitiveness of HUVECs over HASMCs was notably improved after being treated with T0901317-loaded liposomes. Compared to free T0901317 and non-targeted liposomes, the type IV collagen (Col-IV) targeted liposomes could accumulate in the vascular injured area more effectively and inhibit neointimal hyperplasia in a balloon-induced rat carotid artery injury model. Therefore, targeted delivery of LXR agonist might be a very promising therapeutic strategy for anti-restenosis therapy.

α-Iso-cubebene (ICB) is a dibenzocyclooctadiene lignin contained in Schisandra chinensis, a medicinal herb used to improve cardiovascular symptoms. To investigate the mechanisms involved, the effects of ICB on cellular production of reactive oxygen species (ROS) was determined using cultured human THP-1 cells. When THP-1 cells were stimulated with HMGB1, cellular concentration of ROS was increased in dose- and time-dependent manners. These increases were significantly attenuated in cells pretreated with NADPH oxidase inhibitors, diphenyleneiodonium chloride and apocynin, but not by other inhibitors related to ROS generation in monocytes. The expression of constitutively expressed NADPH oxidase (NOX) subunits including NOX1, NOX2, NOX4 and NOX5 was not affected by HMGB1, but HMGB1-induced ROS production was exclusively attenuated in NOX2-deficient cells using siRNA, suggesting an enhanced NOX2 complex assembly. When cells were stimulated with HMGB1, p47phox phosphorylation at ser345, ser359 and ser370 was increased in dose- and time-dependent manners, which were significantly attenuated in ICB (3-10 μg/mL)-pretreated cells. In addition, HMGB1-induced monocyte-macrophage differentiation (MMD) in bone marrow-derived cells isolated from mice were significantly attenuated in cells treated with apocynin and ICB. Also, macrophage infiltration and intimal hyperplasia in the wire-injured femoral artery were significantly attenuated in ICB-treated mice compared to wild-type control mice. The results of this study show that ICB inhibits HMGB1-induced MMD by suppressing ROS production in monocytes, thus suggest that ICB has therapeutic potential for vascular inflammation with subsequent intimal hyperplasia related to vascular injury., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Backgruound: Excessive proliferation and migration of vascular smooth muscle cells (VSMCs), which contributes to the development of occlusive vascular diseases, requires elevated mitochondrial oxidative phosphorylation to meet the increased requirements for energy and anabolic precursors. Therefore, therapeutic strategies based on blockade of mitochondrial oxidative phosphorylation are considered promising for treatment of occlusive vascular diseases. Here, we investigated whether DN200434, an orally available estrogen receptor-related gamma inverse agonist, inhibits proliferation and migration of VSMCs and neointima formation by suppressing mitochondrial oxidative phosphorylation., Methods: VSMCs were isolated from the thoracic aortas of 4-week-old Sprague-Dawley rats. Oxidative phosphorylation and the cell cycle were analyzed in fetal bovine serum (FBS)- or platelet-derived growth factor (PDGF)-stimulated VSMCs using a Seahorse XF-24 analyzer and flow cytometry, respectively. A model of neointimal hyperplasia was generated by ligating the left common carotid artery in male C57BL/6J mice., Results: DN200434 inhibited mitochondrial respiration and mammalian target of rapamycin complex 1 activity and consequently suppressed FBS- or PDGF-stimulated proliferation and migration of VSMCs and cell cycle progression. Furthermore, DN200434 reduced carotid artery ligation-induced neointima formation in mice., Conclusion: Our data suggest that DN200434 is a therapeutic option to prevent the progression of atherosclerosis.

Neointimal hyperplasia (NIH) after revascularization is a key unsolved clinical problem. Various studies have shown that attenuation of the acute inflammatory response on the vascular wall can prevent NIH. MicroRNA146a-5p (miR146a-5p) has been reported to show anti-inflammatory effects by inhibiting the NF-κB pathway, a well-known key player of inflammation of the vascular wall. Here, a nanomedicine, which can reach the vascular injury site, based on polymeric micelles was applied to deliver miR146a-5p in a rat carotid artery balloon injury model. In vitro studies using inflammation-induced vascular smooth muscle cell (VSMC) was performed. Results showed anti-inflammatory response as an inhibitor of the NF-κB pathway and VSMC migration, suppression of reactive oxygen species production, and proinflammatory cytokine gene expression in VSMCs. A single systemic administration of miR146a-5p attenuated NIH and vessel remodeling in a carotid artery balloon injury model in both male and female rats in vivo. MiR146a-5p reduced proinflammatory cytokine gene expression in injured arteries and monocyte/macrophage infiltration into the vascular wall. Therefore, miR146a-5p delivery to the injury site demonstrated therapeutic potential against NIH after revascularization., (© 2022 Federation of American Societies for Experimental Biology.)

The abnormal change of vascular smooth muscle cell (VSMC) behavior is an important cellular event leading to neointimal hyperplasia in atherosclerosis and restenosis. Plantamajoside (PMS), a phenylethanoid glycoside compound of the Plantago asiatica , has been reported to have anti-inflammatory, antioxidative, and anticancer activities. In this study, the protective effects of PMS against intimal hyperplasia and the mechanisms underlying the regulation of VSMC behavior were investigated. MTT and BrdU assays were performed to evaluate the cytotoxicity and cell proliferative activity of PMS, respectively. Rat aortic VSMC migrations after treatment with the determined concentration of PMS (50 and 150  μ M) were evaluated using wound healing and Boyden chamber assays. The inhibitory effects of PMS on intimal hyperplasia were evaluated in balloon-injured (BI) rat carotid artery. PMS suppressed the proliferation in platelet-derived growth factor-BB-induced VSMC, as confirmed from the decrease in cyclin-dependent kinase (CDK)-2, CDK-4, cyclin D1, and proliferating cell nuclear antigen levels. PMS also inhibited VSMC migration, consistent with the downregulated expression and zymolytic activities of matrix metalloproteinase (MMP)2, MMP9, and MMP13. PMS specifically regulated MMP expression through p38 mitogen-activated protein kinase and focal adhesion kinase pathways. Tissue inhibitor of metalloproteinase (TIMP)1 and TIMP2 levels were upregulated via Smad1. TIMPs inhibited the conversion of pro-MMPs to active MMPs. PMS significantly inhibited neointimal formation in BI rat carotid arteries. In conclusion, PMS inhibits VSMC proliferation and migration by upregulating TIMP1 and TIMP2 expression. Therefore, PMS could be a potential therapeutic agent for vascular atherosclerosis and restenosis treatment.

Vascular restenosis remains a major problem in patients with coronary artery disease (CAD) and peripheral artery disease (PAD). Neointimal hyperplasia, defined by post-procedure proliferation and migration of vascular smooth muscle cells (VSMCs) is a key underlying pathology. Here we investigated the role of Interleukin 11 (IL-11) in a mouse model of injury-related plaque development. Apoe -/- mice were fed a hyperlipidaemic diet and subjected to carotid wire injury of the right carotid. Mice were injected with an anti-IL11 antibody (X203), IgG control antibody or buffer. We performed ultrasound analysis to assess vessel wall thickness and blood velocity. Using histology and immunofluorescence approaches, we determined the effects of IL-11 inhibition on VSMC and macrophages phenotypes and fibrosis. Treatment of mice with carotid wire injury using X203 significantly reduced post-endothelial injury vessel wall thickness, and injury-related plaque, when compared to control. Immunofluorescence staining of the injury-related plaque showed that X203 treatment did not reduce macrophage numbers, but reduced the number of VSMCs and lowered matrix metalloproteinase 2 (MMP2) levels and collagen content in comparison to control. X203 treatment was associated with a significant increase in smooth muscle protein 22α (SM22α) positive cells in injury-related plaque compared to control, suggesting preservation of the contractile VSMC phenotype. Interestingly, X203 also reduced the collagen content of uninjured carotid arteries as compared to IgG, showing an additional effect on hyperlipidemia-induced arterial remodeling in the absence of mechanical injury. Therapeutic inhibition of IL-11 reduced vessel wall thickness, attenuated neointimal hyperplasia, and has favorable effects on vascular remodeling following wire-induced endothelial injury. This suggests IL-11 inhibition as a potential novel therapeutic approach to reduce arterial stenosis following revascularization in CAD and PAD patients., (© 2021. The Author(s).)

The aim of the study is to examine the mechanism of Aralia armata (Wall.) Seem (AAS) in improving intimal hyperplasia after vascular injury in rats. Rats with femoral artery injury were randomly divided into three groups: the model group, AAS low-dose group (40 mg/kg), and AAS high-dose group (80 mg/kg). The sham operation group was used as a control group. HE staining was used to observe the changes in femoral artery vessels. Immunohistochemistry was adopted to detect α -SMA, PCNA, GSK-3 β , and β -catenin proteins in femoral artery tissue. The CCK-8 test and wound healing assay were employed to analyze the effect of AAS on proliferation and migration of vascular smooth muscle cells (VSMCs) cultured in vitro . Western blotting (WB) and polymerase chain reaction (PCR) assays were used to evaluate the molecular mechanism. AAS reduced the stenosis of blood vessels and the protein expressions of α -SMA, PCNA, GSK-3 β , and β -catenin compared to the model group. In addition, AAS (0-15  μ g/mL) effectively inhibited the proliferation and migration of VSMCs. Moreover, the results of WB and PCR showed that AAS could inhibit the activation of β -catenin induced by 15% FBS and significantly decrease the expression levels of Wnt3 α , Dvl-1, GSK-3 β , β -catenin, and cyclin D1 in the upstream and downstream of the pathway. AAS could effectively inhibit the proliferation and migration of neointima after vascular injury in rats by regulating the Wnt/ β -catenin signaling pathway., Competing Interests: The authors declare that they have no conflict of interest., (Copyright © 2021 Xiangpei Zhao et al.)

Objective: Since the systemic drugs have been used to reduce the hyperplasic response in the tunica intima, the periadventitial local drug applications to the vascular wall have gained more popularity. In this study, we investigated the effect of bovine serum albumin-glutaraldehyde and polyethylene glycol polymer on neointimal hyperplasia in rabbit carotid artery anastomosis to explore the effects of these two different agents., Methods: 21 New Zealand male rabbits were randomly divided into three groups. The carotid artery transection and anastomosis was performed onthe control group. The bovine serum albumin-glutaraldehyde and the polyethylene glycol polymer were applied locally on the other two groups seperatley after transection and anastomosis of the carotid arteries. At the end of 28-day follow-up, the histological and the immunohistochemical results related to neointimal hyperplasia were compared., Results: The glue residues were detected in the BSA-glutaraldehyde group, but in the PEG polymer group there was no glue residue. The intima thickness and the intima/media thickness ratio in the control group was significantly higher (p<0.05) than the other groups. These values did not differ significantly between the BSA-glutaraldehyde group and the PEG polymer group (p>0.05). The lumen diameter and the area in the control group were significantly higher (p < 0.05) than the BSA-glutaraldehyde group. These values between the control group and the PEG polymer group did not differ significantly (p>0.05). aSMA-positive staining score in the Control group was found to be significantly lower (p < 0.05) than the BSA-glutaraldehyde and PEG polymer group and the VEGF-positive staining score in the control group was found to be significantly higher (p < 0.05) than the BSA-glutaraldehyde and the PEG polymer group., Conclusions: Although the both agents have positive results on neointimal hyperplasia, it would be favorable to use polyethylene glycol polymer, since it does not seem to affect the lumen area and the lumen diameter of the vessel.

Rapidly proliferating cells such as vascular smooth muscle cells (VSMCs) require metabolic programs to support increased energy and biomass production. Thus, targeting glutamine metabolism by inhibiting glutamine transport could be a promising strategy for vascular disorders such as atherosclerosis, stenosis, and restenosis. V-9302, a competitive antagonist targeting the glutamine transporter, has been investigated in the context of cancer; however, its role in VSMCs is unclear. Here, we examined the effects of blocking glutamine transport in fetal bovine serum (FBS)- or platelet-derived growth factor (PDGF)-stimulated VSMCs using V-9302. We found that V-9302 inhibited mTORC1 activity and mitochondrial respiration, thereby suppressing FBS- or PDGF-stimulated proliferation and migration of VSMCs. Moreover, V-9302 attenuated carotid artery ligation-induced neointima in mice. Collectively, the data suggest that targeting glutamine transport using V-9302 is a promising therapeutic strategy to ameliorate occlusive vascular disease., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Excessive proliferation and migration of vascular smooth muscle cells (VSMCs) contribute to the development of atherosclerosis and restenosis. Glycolysis and glutaminolysis are increased in rapidly proliferating VSMCs to support their increased energy requirements and biomass production. Thus, it is essential to develop new pharmacological tools that regulate metabolic reprogramming in VSMCs for treatment of atherosclerosis. The effects of 6-diazo-5-oxo-L-norleucine (DON), a glutamine antagonist, have been broadly investigated in highly proliferative cells; however, it is unclear whether DON inhibits proliferation of VSMCs and neointima formation. Here, we investigated the effects of DON on neointima formation in vivo as well as proliferation and migration of VSMCs in vitro. DON simultaneously inhibited FBS- or PDGF-stimulated glycolysis and glutaminolysis as well as mammalian target of rapamycin complex I activity in growth factor-stimulated VSMCs, and thereby suppressed their proliferation and migration. Furthermore, a DON-derived prodrug, named JHU-083, significantly attenuated carotid artery ligation-induced neointima formation in mice. Our results suggest that treatment with a glutamine antagonist is a promising approach to prevent progression of atherosclerosis and restenosis.

Imatinib, a PDGF receptor tyrosine kinase inhibitor, has been shown to suppress intimal hyperplasia in different animal models under normal metabolic milieu, diabetic, and/or hypercholesterolemic conditions. However, the impact of imatinib treatment on injury-induced neointimal hyperplasia has not yet been investigated in the setting of insulin resistance without frank diabetes. Using a mouse model of high fat diet (HFD)-induced insulin resistance and guidewire-induced arterial injury, the present study demonstrates that intraperitoneal administration of imatinib (25 mg/kg/day) for ~3 weeks resulted in a marked attenuation of neointimal hyperplasia (intima/media ratio) by ~78% (n = 6-9 per group; P < 0.05). Imatinib treatment also led to significant improvements in key metabolic parameters. In particular, imatinib improved insulin resistance and glucose tolerance, as revealed by complete inhibition of HFD-induced increase in HOMA-IR index and AUC IPGTT , respectively. In addition, imatinib treatment led to diminutions in HFD-induced increases in plasma total cholesterol and triglycerides by ~73% and ~59%, respectively. Furthermore, imatinib decreased HFD-induced increase in visceral fat accumulation by ~51% (as determined by epididymal white adipose tissue weight). Importantly, imatinib treatment in HFD-fed mice enhanced plasma levels of high-molecular-weight adiponectin by ~2-fold without affecting total adiponectin. However, there were no significant changes in mean arterial pressure in insulin-resistant state or after imatinib exposure, as measured by tail-cuff method. Together, the present findings suggest that targeting PDGF receptor tyrosine kinase using imatinib may provide a realistic treatment option to prevent injury-induced neointimal hyperplasia and diet-induced insulin resistance in obesity., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The present study was designed to investigate the therapeutic effects of injection of dihydroartemisinin (DHA) into the balloon-injured carotid arteries on balloon injury-induced neointimal formation and to explore whether autophagy is involved in the action of DHA. Percutaneous transluminal balloon angioplasty was performed in Sprague-Dawley rats to induce neointimal formation, immediately after which DHA (100 μmol/l × 1 ml) and/or Rapamycin (1 mg/100 μl), were injected into the balloon-injured carotid arteries. After 14 days, the serum samples and carotid artery tissues were harvested for analysis. Rat aortic vascular smooth muscle cells (VSMCs) were pretreated with DMSO (vehicle), DHA (1, 10, and 100 μmol/l), or 3-methyladenine (3-MA; 10 mM) for 1 h and then stimulated with platelet-derived growth factor-BB (PDGF-BB; 10 ng/ml) for another 24 h. Animal experiments showed that DHA attenuated the balloon injury-induced neointimal formation, inflammation and VSMC phenotypic transition by inhibiting the balloon injury-induced autophagy activation. In vitro results showed that DHA attenuated the PDGF-BB-induced VSMC phenotypic transition, proliferation, and migration by inhibiting the PDGF-BB-induced autophagy activation. Taken together, DHA ameliorates balloon injury-induced neointimal formation through suppressing autophagy. This study provides insights into the development of a drug-eluting stent using DHA., (© 2020 Walter de Gruyter GmbH, Berlin/Boston.)

Neointimal formation and atherogenesis are major vascular complications following percutaneous coronary intervention, and there is lack of pharmacological therapy. This study was aimed to examine the effect of forskolin (FSK), a cyclic adenosine monophosphate (cAMP)-elevating agent, on vascular response to angioplasty wire injury and on atherogenesis in mice. Forskolin treatment reduced neointima formation at 7 and 28 days after wire injury. Early morphometrics of the injured vessels revealed that FSK treatment enhanced endothelial repair and reduced inflammatory cell infiltration. In vitro treatment of primary aortic cells with FSK, at 3-100 μmol/L, increased endothelial cell proliferation, whereas FSK, at 30-100 μmol/L, inhibited smooth muscle cell proliferation. FSK inhibited lipopolysaccharide-induced leucocyte-endothelial interaction in vitro and in vivo. In a mouse model of atherosclerosis driven by dyslipidaemia and hypertension, FSK administration increased endothelial repair and reduced atherosclerotic plaque formation, without affecting blood pressure, plasma lipids or aortic aneurysms formation. In summary, FSK, at doses relevant to human therapeutic use, protects against neointimal hyperplasia and atherogenesis, and this is attributable to its activities on pro-endothelial repair and anti-inflammation. This study raises a potential of clinical use of FSK as an adjunct therapy to prevent restenosis and atherosclerosis after percutaneous coronary intervention., (© 2020 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Disruption of re-endothelialization and haemodynamic balance remains a critical side effect of drug-eluting stents (DES) for preventing intimal hyperplasia. Previously, we found that 5-aminolevulinic acid-mediated sonodynamic therapy (ALA-SDT) suppressed macrophage-mediated inflammation in atherosclerotic plaques. However, the effects on intimal hyperplasia and re-endothelialization remain unknown. In this study, 56 rabbits were randomly assigned to control, ultrasound, ALA and ALA-SDT groups, and each group was divided into two subgroups (n = 7) on day 3 after right femoral artery balloon denudation combined with a hypercholesterolemic diet. Histopathological analysis revealed that ALA-SDT enhanced macrophage apoptosis and ameliorated inflammation from day 1. ALA-SDT inhibited neointima formation without affecting re-endothelialization, increased blood perfusion, decreased the content of macrophages, proliferating smooth muscle cells (SMCs) and collagen but increased elastin by day 28. In vitro, ALA-SDT induced macrophage apoptosis and reduced TNF-α, IL-6 and IL-1β via the ROS-PPARγ-NF-κB signalling pathway, which indirectly inhibited human umbilical artery smooth muscle cell (HUASMC) proliferation, migration and IL-6 production. ALA-SDT effectively inhibits intimal hyperplasia without affecting re-endothelialization. Hence, its clinical application combined with bare-metal stent (BMS) implantation presents a potential strategy to decrease bleeding risk caused by prolonged dual-antiplatelet regimen after DES deployment.

Platelets play an important role in the early stage of arterial remodeling after injury. Integrin GPIIb/IIIα (αIIbβ3) regulates platelet activation in the inside-out and outside-in signaling pathways. The use of tirofiban, an integrin αIIbβ3 inhibitor, in clinical therapy is limited by its short in vivo circulation time. Herein, a controlled drug-release system was formulated using CuS@mSiO2-PEG core-shell nanoparticles as near-infrared-triggered nanocarriers to release tirofiban on demand. The nanocarriers possessed good colloidal stability and very high loading efficiency for the integrin αIIbβ3 inhibitor (14.5 wt% for tirofiban). Local application of αIIbβ3 antagonist-tirofiban on an injured arterial wall inhibited platelet activation, which was accelerated by laser irradiation. Ex vivo platelet-promoted monocyte transmigration trans-well assays revealed decreased monocyte transmigration after platelet activation was inhibited by tirofiban. Two weeks after the wire-induced injury, the intimal area and cellular content were analyzed. The neointimal area was decreased in ApoE-/- mice with CuS@mSiO2-PEG/tirofiban and laser irradiation-promoted tirofiban release, which had limited the neointima formation. The lesions showed a decreased content of macrophages and smooth muscle cells compared with ApoE-/- mice without tirofiban inhibition. Therefore, the action of platelet-integrin αIIbβ3 in neointima formation after vascular injury was successfully inhibited in vivo through the controlled release of tirofiban using a near-infrared-triggered nanocarrier, leading to the decrease of early-stage neointima formation. This study also emphasizes the role of platelets in vascular remodeling and provides a new target, namely integrin αIIbβ3, for the inhibition of neointimal hyperplasia during vascular inflammation.

Introduction: Neointima formation is closely linked to vascular stenosis and occurs after endothelial damage. Hydrogen sulfide is an endogenous pleiotropic mediator with numerous positive effects on the cardio vascular system., Objective: This study evaluates the effect of the slow releasing hydrogen sulfide donor GYY4137 (GYY) on neointimal formation in vivo., Methods: The effect of GYY on neointimal formation in the carotid artery was studied in the FeCl3 injury model in GYY- or vehicle-treated mice. The carotid arteries were studied at days 7 and 21 after treatment by means of histology and immunohistochemistry for proliferating cell nuclear antigen (PCNA) and alpha smooth muscle actin (α-SMA)., Results: GYY treatment significantly reduced the maximal diameter and the area of the newly formed neointima on both days 7 and 21 when compared to vehicle treatment. GYY additionally reduced the number of PCNA- and α-SMA-positive cells within the neointima on day 21 after FeCl3 injury of the carotid artery., Conclusions: Summarizing, single treatment with the slow releasing hydrogen sulfide donor GYY reduced the extent of the newly formed neointima by affecting the cellular proliferation at the site of vascular injury.

In this study, we investigated the role ofhistone deacetylase 4 (HDAC4) and MEG3/miR-125a-5p/interferonregulatoryfactor 1 (IRF1) on vascular smooth muscle cell (VSMCs)proliferation. Platelet derived growth factor (PDGF)-BB was used toinduce the proliferation and migration of VSMCs. The expressionsof MEG3, miR-125a-5p, HDAC4 and IRF1in VSMCs were detectedby qRT-PCR and western blot, respectively. ChIP assay was usedto determine the relationship between MEG3 and HDAC4. Doubleluciferase reporter assay was used to test the regulation betweenmiR-125-5p and IRF1. Results showed that PDGF-BB decreasedthe expression of MEG3 and IRF1, while increased the expressionof miR-125a-5p and HDAC4. In addition, HDAC4 knockdowninhibited the proliferation and migration of VSMCs via upregulatingMEG3 and downregulating miR-125a-5p. MiR-125a-5p inhibitorcould repress the proliferation and migration of VSMCs andalleviate intimal hyperplasia (IH) by directly upregulating IRF1expression. These results suggested that HDAC4 interferenceinhibited PDGF-BB-induced VSMCs proliferation via regulatingMEG3/miR-125a-5p/IRF1 axis, and then alleviated IH.

Vascular progenitors such as endothelial progenitor cells (EPCs) and smooth muscle-like progenitor cells (SMPCs) may play different roles in vascular repair. Ginkgo biloba extract (GBE) is an exogenous activator of heme oxygenase (HO)-1, which has been suggested to improve vascular repair; however, the detailed mechanisms have yet to be elucidated. This study aimed to investigate whether GBE can modulate different vascular progenitor cells by activating HO-1 for vascular repair. A bone marrow transplantation mouse model was used to evaluate the in vivo effects of GBE treatment on wire-injury induced neointimal hyperplasia, which is representative of impaired vascular repair. On day 14 of GBE treatment, the mice were subjected to wire injury of the femoral artery to identify vascular reendothelialization. Compared to the mice without treatment, neointimal hyperplasia was reduced in the mice that received GBE treatment for 28 days in a dose-dependent manner. Furthermore, GBE treatment increased bone marrow-derived EPCs, accelerated endothelial recovery, and reduced the number of SMPCs attached to vascular injury sites. The effects of GBE treatment on neointimal hyperplasia could be abolished by co-treatment with zinc protoporphyrin IX, an HO-1 inhibitor, suggesting the in vivo role of HO-1. In this in vitro study, treatment with GBE activated human early and late EPCs and suppressed SMPC migration. These effects were abolished by HO-1 siRNA and an HO-1 inhibitor. Furthermore, GBE induced the expression of HO-1 by activating PI3K/Akt/eNOS signaling in human late EPCs and via p38 pathways in SMPCs, suggesting that GBE can induce HO-1 in vitro through different molecular mechanisms in different vascular progenitor cells. Accordingly, GBE could activate early and late EPCs, suppress the migration of SMPCs, and improve in vivo vascular repair after mechanical injury by activating HO-1, suggesting the potential role of pharmacological HO-1 activators, such as GBE, for vascular protection in atherosclerotic diseases.

Background: Neointima hyperplasia is the pathological basis of atherosclerosis and restenosis which have been associated with diabetes mellitus (DM). It is controversial for linagliptin and metformin to protect against vascular neointimal hyperplasia caused by DM. Given the combined therapy of linagliptin and metformin in clinical practice, we investigated whether the combination therapy inhibited neointimal hyperplasia in the carotid artery in diabetic rats., Methods and Results: Neointima hyperplasia in the carotid artery was induced by balloon-injury in the rats fed with high fat diet (HFD) combined with low dose streptozotocin (STZ) administration. In vitro, vascular smooth muscle cells (VSMCs) were incubated with high glucose (HG, 30 mM) and the proliferation, migration, apoptosis and collagen deposition were analyzed in VSMCs. We found that the combined therapy, not the monotherapy of linagliptin and metformin significantly inhibited the neointima hyperplasia and improved the endothelium-independent contraction in the balloon-injured cardia artery of diabetic rats, which was associated with the inhibition of superoxide (O 2 -. ) production in the cardia artery. In vitro, HG-induced VSMC remodeling was shown as the remarkable upregulation of PCNA, collagan1, MMP-9, Bcl-2 and migration rate as well as the decreased apoptosis rate. Such abnormal changes were dramatically reversed by the combined use of linagliptin and metformin. Moreover, the AMP-activated protein kinase (AMPK)/Nox4 signal pathway was found to mediate VSMC remodeling responding to HG. Linagliptin and metformin were synergistical to target AMPK/Nox4 signal pathway in VSMCs incubated with HG and in the cardia artery of diabetic rats, which was superior to the monotherapy., Conclusions: We demonstrated that the potential protection of the combined use of linagliptin and metformin on VSMC remodeling through AMPK/Nox4 signal pathway, resulting in the improvement of neointima hyperplasia in diabetic rats. This study provided new therapeutic strategies for vascular stenosis associated with diabetes., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: The high lifetime risk of vascular disease is one of the important issues that plague patients with diabetes mellitus. Systemic oral vildagliptin administration favors endothelial recovery and inhibits smooth muscle cell (SMC) proliferation. However, the localized release of vildagliptin in the diabetic vessel damage has seldom been investigated., Research Design and Methods: In this work, nanofiber-eluting stents that loaded with vildagliptin, a dipeptidyl peptidase-4 enzyme (DPP-4) inhibitor, was fabricated to treat diabetic vascular disease. To prepare nanofibers, the poly (D,L)-lactide-co-glycolide (PLGA) and vildagliptin were mixed using hexafluoroisopropanol and electrospinning process. In vitro and in vivo release rates of the vildagliptin were characterized using high-performance liquid chromatography., Results: Effective vildagliptin concentrations were delivered for more than 28 days from the nanofibrous membranes coating on the surface of the stents in vitro and in vivo. The vildagliptin-eluting PLGA membranes greatly accelerated the recovery of diabetic endothelia and reduced SMC hyperplasia. The type I collagen content of the diabetic vascular intimal area that was treated by vildagliptin-eluting stents was lower than that of the non-vildagliptin-eluting group., Conclusion: The experimental results revealed that stenting with vildagliptin-eluting PLGA membranes could potentially promote healing for diabetic arterial diseases., Competing Interests: The authors report no conflicts of interest with respect to this work., (© 2019 Lee et al.)

Background and Purpose: The increased proliferation and migration of vascular smooth muscle cells (VSMCs) after arterial injury contributes greatly to the pathogenesis of neointimal hyperplasia. As a major component of epigenetics, histone methylation plays an important role in several cardiovascular diseases. However, its role in restenosis is still unclear., Experimental Approach: Human aortic VSMCs were challenged with PDGF-BB, and total histones were extracted and analysed by HPLC/MS. For the in vivo study, rats were subjected to wire-guided common carotid injury., Key Results: PDGF-BB markedly increased the H3K27me3 level, as demonstrated by use of HPLC/MS and confirmed by western blot analysis. Enhancer of zeste homologue 2 (EZH2), the histone H3K27 methyltransferase component of polycomb repressive complex 2, was also up-regulated by PDGF-BB in VSMCs, and in the neointimal hyperplasia induced by wire injury of the rat carotid artery. Furthermore, inhibiting H3K27me3 by treatment with 3-μM UNC1999, an EZH2/1 inhibitor, significantly suppressed PDGF-BB-induced VSMC proliferation compared with the PDGF-BB-treated group. Consistently, neointimal formation was significantly attenuated by oral or perivascular administration of UNC1999 compared with the sham group. Mechanistically, the increase in H3K27me3 inhibited the transcription of the cyclin-dependent kinase inhibitor p16 INK4A and thus promoted VSMC proliferation., Conclusions and Implications: Vascular injury elevated the expression of EZH2 and the downstream target H3K27me3, which suppressed p16 INK4A expression in VSMCs and promoted VSMC proliferation and neointimal hyperplasia. EZH2 inhibition might be a potential therapeutic target for restenosis., (© 2019 The British Pharmacological Society.)

Background: The beneficial effects of angiotensin II type 1 receptor blockers (ARBs) on atherosclerosis have been demonstrated in numerous studies. We investigated the effects of fimasartan on reducing neointimal formation and systemic inflammation after carotid artery (CA) injury in Apolipoprotein E knockout (ApoE KO) mice., Methods: ApoE KO mice were randomly allocated to Group I (without CA injury), Group II (without CA injury + Fimasartan), Group III (CA injury), and Group IV (CA injury + Fimasartan). Fimasartan was orally administered everyday starting 3 days before iatrogenic left CA injury., Results: At 28 days, neointimal hyperplasia and the inflammatory cytokines including TNFα, IL-6, ICAM, and MMP-9 in the peripheral blood were significantly reduced in Groups II and IV compared to Groups I and III, respectively. All fimasartan-administered groups revealed significant increases of CD4 + CD25 + Foxp3 + regulatory T (Treg) cells with increased plasma levels of IL-10 and TGFβ. In addition, increased CD8 + T cells by fimasartan were correlated with reduced smooth muscle cell (SMC) proliferation in the neointima in Groups II and IV. Furthermore, the populations of Treg and CD8 + T cells in total splenocytes were increased in Groups II and IV compared to Groups I and III, respectively. The enlargement of spleens due to CA injury in the Group III was attenuated by fimasartan, as shown in the Group IV. These data indicate that fimasartan significantly reduced SMC proliferation in neointima and increased Treg cells in ApoE KO CA injury mice., Conclusions: This study suggests fimasartan could be an efficient strategy for reduction of atherosclerotic progression, with a decrease in immune response and systemic inflammation.

Objectives: This study aims to evaluate the effects of dihydroartemisinin (DHA) on the balloon injury-induced neointimal formation in rats and to investigate the underlying mechanism., Methods: The balloon-induced carotid artery injury model was established in male Sprague-Dawley rats, immediately after which the DHA solution was injected into the tail vein of rats. In in vitro assays, primary rat vascular smooth muscle cells (VSMCs) were pretreated with DHA and then coincubated with LPS., Results: DHA ameliorated the induced neointimal formation and fibrosis but enhanced apoptosis in rat carotid artery after balloon injury. Furthermore, DHA suppressed migration and enhanced apoptosis of the lipopolysaccharide (LPS)-treated primary VSMCs in vitro. Moreover, in both the balloon injury-induced rat sera and the LPS-treated VSMCs, DHA significantly inhibited proinflammatory cytokines, including interleukin-1β, tumor necrosis factor-ɑ, and matrix metalloproteinase-1. Importantly, DHA significantly decreased the balloon injury-increased expression of nuclear factor kappa B (NF-κB) subunit NF-κB p65 expression, and increased the balloon injury-reduced expression of inhibitor of NF-κB-alpha, indicating the inhibition of the IκB/NF-κB pathway., Conclusion: DHA significantly inhibited neointimal formation in balloon-induced rat carotid artery injury and the mechanism may be related to the inhibition of IκB/NF-κB signaling, which alleviates the inflammatory response., (© 2018 Wiley Periodicals, Inc.)

Background: Compounds of the inner shell of chestnut (Castanea crenata) have diverse biological activities, including anti-cancer and anti-oxidant activities. Here we explored the effects of an extract of chestnut inner shells and of its bioactive component scoparone on vascular smooth muscle cell migration and vessel damage., Results: The ethanol extract of chestnut inner shells, containing 11 major compounds, inhibited platelet-derived growth factor (PDGF)-BB-induced migration of rat aortic smooth muscle cells (RASMCs). Among these compounds, scoparone (6,7-dimethoxycoumarin) suppressed RASMC migration and wound healing in response to PDGF-BB but did not affect RASMC proliferation. In RASMCs, scoparone inhibited the PDGF-BB-induced rat aortic sprout outgrowth and attenuated the PDGF-BB-mediated increase in phosphorylation of mitogen-activated protein kinases (MAPKs), p38 MAPK and extracellular signal-regulated kinase 1/2. The in vivo administration of scoparone resulted in the attenuation of neointima formation in balloon-injured carotid arteries of rats., Conclusion: These findings demonstrate that scoparone, found in chestnut inner shells, may inhibit cell migration through suppression of the phosphorylation of MAPKs in PDGF-BB-treated RASMCs, probably contributing to the reduction of neointimal hyperplasia induced after vascular injury. Therefore, scoparone and chestnut inner shell may be a potential agent or functional food, respectively, for the prevention of vascular disorders such as vascular restenosis or atherosclerosis. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)

Vascular endothelial growth factor (VEGF) is a promising molecule for cardiovascular diseases therapy. But lack of a targeted delivery system limits its translation into clinical application. This study aimed to develop stably overexpressing VEGF macrophages for targeted VEGF delivery to injured arteries and determine their potential for repairing of the damaged endothelium. Wire-induced carotid artery injury model was established in atherosclerosis-prone mice. It was observed that the VEGF-modified macrophages were recruited to the site of vascular injury and incorporated into new endothelium formation. VEGF-modified macrophages therapy accelerated reendothelialization and attenuated neointima formation. The VEGF protein level in tissues of injured arteries treated with VEGF-modified macrophages was increased. The upregulated C-C chemokine receptor type 5 (CCR5) and unaltered CCR2 protein levels were verified in VEGF-modified macrophages in vitro. Moreover, enhanced nitric oxide (NO) production in the culture medium of VEGF-modified macrophages was demonstrated. Our results indicated that VEGF-modified macrophages acted as vectors of VEGF targeting injured arteries, promoting the repairing directly by incorporating into new endothelium formation and indirectly by secreting sustainable VEGF and producing NO locally. This study represents a novel therapeutic application of targeted cell therapy with VEGF-modified macrophages for cardiovascular diseases., (© 2019 Wiley Periodicals, Inc.)

Background: Salvianolic acid B (Sal B), a water-soluble compound extracted from Salvia miltiorrhiza that has been widely used to treat cardiovascular diseases for hundreds of years in China, exerts cardiovascular protection by multiple mechanisms. miR-146a is involved in vascular smooth muscle cell (VSMC) phenotypic modulation and proliferation. However, it has yet to be investigated whether the cardiovascular protective effect of Sal B is mediated by miR-146a., Purpose: To determine the relationship among the cardiovascular protective effect of Sal B, miR-146a expression, and VSMC proliferation., Methods: MTS assay and cell counting were performed to evaluate the effect of Ang II, Sal B and miR-146a on VSMC proliferation. The neointima hyperplasia was assessed by hematoxylin/eosin staining. qRT-PCR was used to detect the expression of miR-146a, KLF5, cyclin D1 and PCNA. Western blot analysis was used to detect the expressions of KLF5, cyclin D1 and PCNA after miR-20b-5p was knocked down or overexpressed in VSMC., Results: Sal B suppressed intimal hyperplasia induced by carotid artery ligation and decreased Ang II-induced VSMC proliferation by down-regulating the positive cell-cycle regulators KLF5 and cyclin D1. Further experiments showed that VSMC proliferation and upregulation of KLF5 and cyclin D1 induced by Ang II were accompanied by elevated miR-146a level. Furthermore, overexpression of miR-146a promoted and knockdown of miR-146a reduced Ang II-induced VSMC proliferation and ameliorated intimal hyperplasia induced by carotid artery ligation. Sal B inhibited Ang II-induced VSMC proliferation by suppressing miR-146a expression., Conclusion: Sal B inhibited Ang II-induced VSMC proliferation in vitro and intimal hyperplasia in vivo by downregulating miR-146a expression., (Copyright © 2018. Published by Elsevier GmbH.)

Enhanced mitochondrial respiration in vascular smooth muscle cells (VSMCs) is involved in neointima formation in response to vascular injury. In the present study, we investigated the effect of rotenone (ROT), a mitochondrial respiratory chain complex I inhibitor, on VSMC proliferation and migration in vitro, and on femoral artery neointimal hyperplasia induced by wire injury. ROT treatment remarkably ameliorated neointima formation after vascular injury in line with the reduced collagen deposition and significantly restored α-smooth muscle actin (SMA) expression in the neointima. In vitro, ROT markedly suppressed platelet-derived growth factor (PDGF)-BB-induced mouse aorta smooth muscle (MOVA) cell proliferation, migration, and adenosine triphosphate (ATP) production, while the cell viability of MOVA cells was not affected by ROT at concentrations of 10-100 nM. Meanwhile, ROT blocked PDGF-BB-induced cell cycle progression by arresting cell cycle in G0/G1 phase. Interestingly, ROT inhibited the phosphorylation of protein kinase B (AKT), but not extracellular signal-regulated kinase (ERK) 1/2, in response to PDGF-BB, accompanied with the blockade of matrix metalloproteinase-9 (MMP-9) upregulation and reactive oxygen species (ROS) production. These findings indicated that ROT could block neointima formation by preventing the proliferation and migration of MOVA cells, possibly by inhibiting the mitochondrial respiratory chain activity, ATP production, AKT phosphorylation, MMP-9 activation, and ROS production. Thus, inhibiting mitochondrial respiratory chain activity might represent a new strategy to treat neointima formation-associated vascular diseases., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Nanoparticles promise to advance strategies to treat vascular disease. Since being harnessed by the cancer field to deliver safer and more effective chemotherapeutics, nanoparticles have been translated into applications for cardiovascular disease. Systemic exposure and drug-drug interactions remain a concern for nearly all cardiovascular therapies, including statins, antithrombotic, and thrombolytic agents. Moreover, off-target effects and poor bioavailability have limited the development of completely new approaches to treat vascular disease. Through the rational design of nanoparticles, nano-based delivery systems enable more efficient delivery of a drug to its therapeutic target or even directly to the diseased site, overcoming biological barriers and enhancing a drug's therapeutic index. In addition, advances in molecular imaging have led to the development of theranostic nanoparticles that may simultaneously act as carriers of both therapeutic and imaging payloads. The following is a summary of nanoparticle therapy for atherosclerosis, thrombosis, and restenosis and an overview of recent major advances in the targeted treatment of vascular disease.

Percutaneous coronary intervention (PCI) is main treatment for acute coronary syndrome (ACS). However, restenosis caused by PCI-induced injury influences the outcome of patients. Linagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, has been reported to ameliorate intimal hyperplasia post vascular injury. The underlying mechanisms by which linagliptin protects against balloon injury are unclear and require to be explored. Herein, Wistar rats with carotid artery balloon injury were given 1, 2 or 3 mg/kg/day linagliprin for 6 weeks. We found that linagliptin attenuated vascular injury-mediated neointima formation in rats without affecting body weight and blood glucose levels. ELISA results indicated that linagliptin significantly reduced overproduction of cytokines including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and IL-6 post balloon injury. By detecting the level of malondialdehyde (MDA) and the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), we found that linagliptin prevented balloon injury-induced oxidative stress. Additionally, linagliptin decreased the level of Kelch ECH-associating protein 1 (KEAP1) compared with injury group. Results of Western blots and electrophoretic mobility shift assay (EMSA) demonstrated that linagliptin augmented nuclear accumulation of nuclear factor-E2-related factor 2 (NRF2) and its binding ability to target genes in rats with balloon injury. Moreover, heme oxygenase-1 (HO-1) and NAD (P) H quinine oxidoreductase 1 (NQO1), two downstream targets of NRF2, were further up-regulated after linagliptin treatment compared with injury group. In conclusion, our data suggest that linagliptin protects carotid artery from balloon injury-induced neointima formation and activates the NRF2 antioxidant pathway.

Aims: Recently, incretin therapy has attracted increasing attention because of its potential use in tissue-protective therapy. Neuron-derived orphan receptor 1 (NOR1) is a nuclear orphan receptor that regulates vascular smooth muscle cell (VSMC) proliferation. In the present study, we investigated the vascular-protective effect of Exendin-4 (Ex-4), a glucagon-like peptide-1 receptor agonist, by inhibiting NOR1 expression in VSMCs., Methods: We classified 7-week-old male 129X1/SvJ mice into control group and Ex-4 low- and high-dose-treated groups fed normal or high-fat diets, respectively. Endothelial denudation injuries were induced in the femoral artery at 8 weeks of age, followed by the evaluation of neointima formation at 12 weeks of age. To evaluate VSMC proliferation, bromodeoxyuridine incorporation assay and cell cycle distribution analysis were performed. NOR1 and cell cycle regulators were detected using immunohistochemistry, western blotting, quantitative reverse-transcription polymerase chain reaction, and luciferase assays., Results: Ex-4 treatment reduced vascular injury-induced neointima formation compared with controls. In terms of VSMCs occupying the neointima area, VSMC numbers and NOR1-expressing proliferative cells were significantly decreased by Ex-4 in a dose-dependent manner in both diabetic and non-diabetic mice. In vitro experiments using primary cultured VSMCs revealed that Ex-4 attenuated NOR1 expression by reducing extracellular signal-regulated kinase-mitogen-activated protein kinase and cAMP-responsive element-binding protein phosphorylations. Furthermore, in the cell cycle distribution analysis, serum-induced G1-S phase entry was significantly attenuated by Ex-4 treatment of VSMCs by inhibiting the induction of S-phase kinase-associated protein 2., Conclusion: Ex-4 attenuates neointima formation after vascular injury and VSMC proliferation possibly by inhibiting NOR1 expression.

Background: Specialized proresolving mediators from ω-3 polyunsaturated fatty acid may control resolution of inflammation. We evaluated the influence of two specialized proresolving mediators, resolvin D1 (RvD1) and protectin D1 isomer (PD1 iso) on neointimal hyperplasia after balloon injury., Materials and Methods: Sprague Dawley male rats at 12-14 wk of age were injured as a model of balloon angioplasty. Then, 1 μg/rat of RvD1 or PD1 iso was administered intravenously via the tail vein immediately and 2 d after angioplasty. The proliferation of injured artery and the infiltration of leukocytes, monocytes, and macrophages at 3 d after injury were evaluated by immunostaining. The activity of the inflammatory transcription factor nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) in the injured artery at 3 d after injury was evaluated using an enzyme-linked immuno sorbent assay kit. The proliferation of the neointima was evaluated by calculating the ratio of the neointimal and medial areas using specimens at 14 d after injury., Results: RvD1 and PD1 iso attenuated proliferation of medial cells (P < 0.05) and infiltration of leukocytes (P < 0.05) and monocytes/macrophages (P < 0.01). Although both RvD1 and PD1 iso mitigated NFκB activity (P < 0.01), RvD1 attenuated this activity more strongly (P < 0.01). RvD1 decreased neointimal hyperplasia by 37.3% (P < 0.01), whereas PD1 iso decreased neointimal hyperplasia by 31.8% (P < 0.05) (RvD1 versus PD1 iso: P = 0.51)., Conclusions: RvD1 and PD1 iso reduced the activity of inflammatory transcription factor NFκB within the injured artery and attenuated inflammatory cell infiltration, leading to a reduction in early inflammation and subsequent neointimal hyperplasia., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)