Nobiletin Inhibits PDGF-BB-induced vascular smooth muscle cell proliferation and migration and attenuates neointimal hyperplasia in a rat carotid artery injury model

Nox1-based NADPH oxidase regulates the Par protein complex activity to control cell polarization

Cell migration is essential for many biological and pathological processes. Establishing cell polarity with a trailing edge and forming a single lamellipodium at the leading edge of the cell is crucial for efficient directional cell migration and is a hallmark of mesenchymal cell motility. Lamellipodia formation is regulated by spatial-temporal activation of the small GTPases Rac and Cdc42 at the front edge, and RhoA at the rear end. At a molecular level, partitioning-defective (Par) protein complex comprising Par3, Par6, and atypical Protein Kinase (aPKC isoforms ζ and λ/ι) regulates front-rear axis polarization. At the front edge, integrin clustering activates Cdc42, prompting the formation of Par3/Par6/aPKC complexes to modulate MTOC positioning and microtubule stabilization. Consequently, the Par3/Par6/aPKC complex recruits Rac1-GEF Tiam to activate Rac1, leading to lamellipodium formation. At the rear end, RhoA-ROCK phosphorylates Par3 disrupting its interaction with Tiam and inactivating Rac1. RhoA activity at the rear end allows the formation of focal adhesions and stress fibers necessary to generate the traction forces that allow cell movement. Nox1-based NADPH oxidase is necessary for PDGF-induced migration in vitro and in vivo for many cell types, including fibroblasts and smooth muscle cells. Here, we report that Nox1-deficient cells failed to acquire a normal front-to-rear polarity, polarize MTOC, and form a single lamellipodium. Instead, these cells form multiple protrusions that accumulate Par3 and active Tiam. The exogenous addition of H2O2 rescues this phenotype and is associated with the hyperactivation of Par3, Tiam, and Rac1. Mechanistically, Nox1 deficiency induces the inactivation of PP2A phosphatase, leading to increased activation of aPKC. These results were validated in Nox1y/- primary mouse aortic smooth muscle cells (MASMCs), which also showed PP2A inactivation after PDGF-BB stimulation consistent with exacerbated activation of aPKC. Moreover, we evaluated the physiological relevance of this signaling pathway using a femoral artery wire injury model to generate neointimal hyperplasia. Nox1y/- mice showed increased staining for the inactive form of PP2A and increased signal for active aPKC, suggesting that PP2A and aPKC activities might contribute to reducing neointima formation observed in the arteries of Nox1y/- mice.

circHECTD1 Promotes the Proliferation and Migration of Human Brain Vascular Smooth Muscle Cells via Interacting with KHDRBS3 to Stabilize EZH2 mRNA Expression

Purpose

The objective of this paper is to explore the role of circHECTD1 in vascular smooth muscle cells (VSMCs) and atherosclerosis (AS).

Methods

VSMCs were treated with platelet-derived growth factor-BB (PDGF-BB) in vitro, and the level of circHECTD1 was determined using qRT-PCR. Cell proliferation, migration, and invasion were analyzed using CCK8 and transwell assays. Cell apoptosis and cell cycle were analyzed using flow cytometry. The binding interaction between circHECTD1 and KHDRBS3 or EZH2 was investigated using the RIP, RNA pull-down.

Results

CircHECTD1 was upregulated in PDGF-BB-induced VSMCs with a dose-dependent and time-dependent manner. Knockdown of circHECTD1 suppressed VSMCsproliferation and migration and enhanced cell apoptosis in VSMCs, while circHECTD1 overexpression yielded opposite effects. Mechanistically, circHECTD1 could interact with KHDRBS3, thus enhanced the stability of EZH2 mRNA and increased EZH2 protein level. In addition, silencing EZH2 in VSMCs reversed the proliferation-enhancing effect of circHECTD1 overexpression.

Conclusion

Our findings provided providing a potential prognostic and therapy biomarker for AS.

The biological clock enhancer nobiletin ameliorates steatosis in genetically obese mice by restoring aberrant hepatic circadian rhythm

Nonalcoholic fatty liver disease (NAFLD) is associated with disruption of homeostatic lipid metabolism, but underlying processes are poorly understood. One possible mechanism is impairment in hepatic circadian rhythm, which regulates key lipogenic mediators in the liver and whose circadian oscillation is diminished in obesity. Nobiletin enhances biological rhythms by activating RAR-related orphan receptor nuclear receptor, protecting against metabolic syndrome in a clock-dependent manner. The effect of nobiletin in NAFLD is unclear. In this study, we investigate the clock-enhancing effects of nobiletin in genetically obese (db/db) PER2::LUCIFERASE reporter mice with fatty liver. We report microarray expression data suggesting hepatic circadian signaling is impaired in db/db mice with profound hepatic steatosis. Circadian PER2 activity, as assessed by mRNA and luciferase assay, was significantly diminished in liver of db/db PER2::LUCIFERASE reporter mice. Continuous animal monitoring systems and constant dark studies suggest the primary circadian defect in db/db mice lies within peripheral hepatic oscillators and not behavioral rhythms or the master clock. In vitro, nobiletin restored PER2 amplitude in lipid-laden PER2::LUCIFERASE reporter macrophages. In vivo, nobiletin dramatically upregulated core clock gene expression, hepatic PER2 activity, and ameliorated steatosis in db/db PER2::LUCIFERASE reporter mice. Mechanistically, nobiletin reduced serum insulin levels, decreased hepatic Srebp1c, Acaca1, Tnfα, and Fgf21 expression, but did not improve Plin2, Plin5, or Cpt1, suggesting nobiletin attenuates steatosis in db/db mice via downregulation of hepatic lipid accumulation. These data suggest restoring endogenous rhythm with nobiletin resolves steatosis in obesity, proposing that hypothesis that targeting the biological clock may be an attractive therapeutic strategy for NAFLD.NEW & NOTEWORTHY NAFLD is the most common chronic liver disease, but underlying mechanisms are unclear. We show here that genetically obese (db/db) mice with fatty liver have impaired hepatic circadian rhythm. Hepatic Per2 expression and PER2 reporter activity are diminished in db/db PER2::LUCIFERASE mice. The biological clock-enhancer nobiletin restores hepatic PER2 in db/db PER2::LUCIFERASE mice, resolving steatosis via downregulation of Srebp1c. These studies suggest targeting the circadian clock may be beneficial strategy in NAFLD.

Therapeutic potential of traditional Chinese medicine in atherosclerosis: A review

Atherosclerosis is the onset of endothelial cell damage and is characterized by abnormal accumulation of fibrinogen and lipid in large and middle arteries. Recent researches indicate that traditional Chinese medicine including Notoginseng Radix et Rhizoma, Astragali Radix, Salviae Miltiorrhizae Radix et Rhizoma, Ginseng Radix et Rhizoma, Fructus Crataegi, Glycyrrhizae Radix et Rhizoma, Polygoni Multiflori Radix, Fructus Lycii, and Coptidis Rhizoma have therapeutic effects on atherosclerosis. Furthermore, the pharmacological roles of these kinds of traditional Chinese medicine in atherosclerosis refer to endothelial function influences, cell proliferation and migration, platelet aggregation, thrombus formation, oxidative stress, inflammation, angiogenesis, apoptosis, autophagy, lipid metabolism, and the gut microbiome. Traditional Chinese medicine may serve as potential and effective anti-atherosclerosis drugs. However, a critical study has shown that Notoginseng Radix et Rhizoma may also have toxic effects including pustules, fever, and elevate circulating neutrophil count. Further high-quality studies are still required to determine the clinical safety and efficacy of traditional Chinese medicine and its active ingredients.

Scaffold Engineering with Flavone-Modified Biomimetic Architecture for Vascular Tissue Engineering Applications

BACKGROUND

Vascular intimal hyperplasia (IH) is one of the key challenges in the clinical application of small-diameter vascular grafts. Current tissue engineering strategies focus on vascularization and antithrombotics, yet few approaches have been developed to treat IH. Here, we designed a tissue-engineered vascular scaffold with portulaca flavonoid (PTF) composition and biomimetic architecture.

METHOD

By electrospinning, PTF is integrated with biodegradable poly(ε-caprolactone) (PCL) into a bionic vascular scaffold. The structure and functions of the scaffolds were evaluated based on material characterization and cellular biocompatibility. Human vascular smooth muscle cells (HVSMCs) were cultured on scaffolds for up to 14 days.

RESULTS

The incorporation of PTF and preparation parameters during fabrication influences the morphology of the scaffold, including fibre diameter, structure, and orientation. Compared to the PCL scaffold, the scaffolds integrated with bioactive PTF show better hydrophilicity and degradability. HVSMCs seeded on the scaffold alongside the fibres exhibit fusiform-like shapes, indicating that the scaffold can provide contact guidance for cell morphology alterations. This study demonstrates that the PCL/PTF (9.1%) scaffold inhibits the excessive proliferation of HVSMCs without causing cytotoxicity.

CONCLUSION

The study provides insights into the problem of restenosis caused by IH. This engineered vascular scaffold with complex function and preparation is expected to be applied as a substitute for small-diameter vascular grafts.

Citrus flavonoids and their antioxidant evaluation

The antioxidant ability is the link and bridge connecting a variety of biological activities. Citrus flavonoids play an essential role in regulating oxidative stress and are an important source of daily intake of antioxidant supplements. Many studies have shown that citrus flavonoids promote health through antioxidation. In this review, the biosynthesis, composition and distribution of citrus flavonoids were concluded. The detection methods of antioxidant capacity of citrus flavonoids were divided into four categories: chemical, cellular, animal and clinical antioxidant capacity evaluation systems. The modeling methods, applicable scenarios, and their relative merits were compared based on these four systems. The antioxidant functions of citrus flavonoids under different evaluation systems were also discussed, especially the regulation of the Nrf2-antioxidases pathway. Some shortcomings in the current research were pointed out, and some suggestions for progress were put forward.

The role of extracellular vesicles in neointima formation post vascular injury

Pathological neointimal growth can develop in patients as a result of vascular injury following percutaneous coronary intervention and coronary artery bypass grafting using autologous saphenous vein, leading to arterial or vein graft occlusion. Neointima formation driven by intimal hyperplasia occurs as a result of a complex interplay between molecular and cellular processes involving different cell types including endothelial cells, vascular smooth muscle cells and various inflammatory cells. Therefore, understanding the intercellular communication mechanisms underlying this process remains of fundamental importance in order to develop therapeutic strategies to preserve endothelial integrity and vascular health post coronary interventions. Extracellular vesicles (EVs), including microvesicles and exosomes, are membrane-bound particles secreted by cells which mediate intercellular signalling in physiological and pathophysiological states, however their role in neointima formation is not fully understood. The purification and characterization techniques currently used in the field are associated with many limitations which significantly hinder the ability to comprehensively study the role of specific EV types and make direct functional comparisons between EV subpopulations. In this review, the current knowledge focusing on EV signalling in neointima formation post vascular injury is discussed.

Farrerol maintains the contractile phenotype of VSMCs via inactivating the extracellular signal-regulated protein kinase 1/2 and p38 mitogen-activated protein kinase signaling

Farrerol, a dihydroflavone isolated from Rhododendron dauricum L., can inhibit vascular smooth muscle cell (VSMC) proliferation and exert a protective effect on H₂O₂-induced vascular endothelial cells injury. In this study, we investigated the effects of farrerol on VSMC phenotypic modulation and balloon injury-induced vascular neointimal formation and explored the underlying mechanisms. Serum-starved rat thoracic aorta SMCs (RASMCs) were first pretreated with farrerol (3, 10, and 30 μM, respectively), U0126 (a MEK kinase inhibitor), and SB203580 (a p38 kinase inhibitor), and followed by treatment with serum (10% FBS). The expression of several VSMC-specific markers, including α-SMA, SM22α, and OPN, were analyzed by western blot. Phosphorylation of extracellular signal-regulated protein kinase 1/2 (ERK 1/2) and p38 mitogen-activated protein kinase (MAPK) was also investigated. Farrerol inhibited the serum-induced transition of RASMCs from the contractile to the synthetic phenotype, and this was associated with a decrease in α-SMA and SM22α expression, and an increase in OPN expression. Farrerol also inhibited serum-induced phosphorylation of ERK1/2 and p38MAPK in RASMCs. Moreover, U0126 and SB203580 both inhibited the serum-induced phenotypic transition of RASMCs. These findings indicate that farrerol can maintain the contractile phenotype of VSMCs partly via inactivating the ERK1/2 and p38 MAPK signaling pathways. Using a rat model of carotid artery balloon injury, inhibition of VSMC phenotypic transition and suppression of neointimal formation were confirmed in vivo following the perivascular application of farrerol. Our results suggested that farrerol could be a promising lead compound for the treatment of vascular proliferative diseases.

Ameliorative Effects and Cellular Aspects of Phytoconstituents in Atherosclerosis

Atherosclerosis is a cardiovascular disease that involves vessels through the development of fatty streaks and plaques. Plant-based compounds can help treat or prevent atherosclerosis by affecting various factors that are involved in the disease. The present review discusses our current knowledge of the major cellular and molecular mechanisms of phytotherapeutics for the treatment of atherosclerosis. Numerous studies have evaluated the antiatherosclerotic activity of phytoconstituents to provide preliminary evidence of efficacy, but only a few studies have delineated the underlying molecular mechanisms. Plant-derived phytotherapeutics primarily targets abnormal levels of lipoproteins, endothelial dysfunction, smooth muscle cell migration, foam cell development, and atheromatous plaque formation. Nonetheless, the principal mechanisms that are responsible for their therapeutic actions remain unclear. Further pharmacological studies are needed to elucidate the underlying molecular mechanisms of the antiatherosclerotic response to these phytoconstituents.

Nobiletin suppresses IL-21/IL-21 receptor-mediated inflammatory response in MH7A fibroblast-like synoviocytes (FLS): An implication in rheumatoid arthritis

The mechanisms driving the development and progression of Rheumatoid arthritis (RA) are complex, novel targeted therapies are gaining traction as potential methods to prevent or slow the progression of RA. Nobiletin is a derivative of citrus fruit that has been shown to attenuate the development of osteoarthritis and inhibit the expression of proinflammatory cytokines. However, the exact mechanisms by which nobiletin exerts these chondroprotective effects remain poorly understood. In the present study, we investigated the impact of nobiletin in mediating the effects of interleukin-21 (IL-21) in MH7A fibroblast-like synoviocytes (FLS), the main cell type found in the articular synovium. Firstly, we demonstrate that nobiletin (25 μM and 50 μM) reduced the expression of the IL-21 receptor by 29% and 51%, respectively, in FLS. Additionally, our findings demonstrate that nobiletin potently ameliorated IL-21-induced increased production of reactive oxygen species and 4-hydroxynonenal, increased expression of interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), and high-mobility group box 1 (HMGB1), and decreased mitochondrial membrane potential. We also demonstrate the ability of nobiletin to attenuate IL-21-induced expression of matrix metalloproteinases 3 and 13 (MMP-3, MMP-13), key degradative enzymes involved in RA-associated cartilage destruction. Finally, we show that the effects of nobiletin are mediated through the JAK1/STAT3 pathway, as nobiletin significantly reduced the phosphorylation of both JAK1 and STAT3. Taken together, our findings indicate that nobiletin may offer a safe and effective treatment against the development and progression of RA induced by the expression of IL-21 and its receptor.

Nobiletin Delays Aging and Enhances Stress Resistance of Caenorhabditis elegans

Nobiletin (NOB), one of polymethoxyflavone existing in citrus fruits, has been reported to exhibit a multitude of biological properties, including anti-inflammation, anti-oxidation, anti-atherosclerosis, neuroprotection, and anti-tumor activity. However, little is known about the anti-aging effect of NOB. The objective of this study was to determine the effects of NOB on lifespan, stress resistance, and its associated gene expression. Using Caenorhabditis elegans, an in vivo nematode model, we found that NOB remarkably extended the lifespan; slowed aging-related functional declines; and increased the resistance against various stressors, including heat shock and ultraviolet radiation. Also, NOB reduced the effects of paraquat stressor on nematodes and scavenged reactive oxygen species (ROS). Furthermore, gene expression revealed that NOB upregulated the expression of sod-3, hsp-16.2, gst-4, skn-1, sek-1, and sir-2.1, which was suggested that anti-aging activity of NOB was mediated most likely by activation of the target genes of the transcription factors including dauer formation (DAF)-16, heat-shock transcription factor (HSF)-1, and skinhead (SKN)-1. In summary, NOB has potential application in extension of lifespan, and its associated healthspan and stress resistances.

Nobiletin enhances the survival of random pattern skin flaps: Involvement of enhancing angiogenesis and inhibiting oxidative stress

Random-pattern flap necrosis is a serious challenge for plastic surgeons. Nobiletin (NOB) is a polymethoxylated flavonoid extracted from citrus fruits reported to have antioxidant, anti-inflammatory and anti-apoptotic effects. Our experiment evaluated the impact of NOB on the viability of random flaps. Thirty six male "McFarlane flap" rat models were separated into two equal groups: a control group and an experimental group treated with 10 mg/kg of NOB. After 7 days, the range of necrosis was calculated, and a histological analysis was performed on tissue specimens. Immunohistochemical staining, lead oxide-gelatin angiography, and a Laser Doppler perfusion imager were used to assess angiogenesis and measure oxidative stress, as indicated by superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels. The average survival area of flap was greater in the NOB-treated group than that in the control group. The NOB-treated group mitigated oxidative stress via augmented SOD, reduced MDA, and enhanced vascular endothelial growth factor (VEGF) expression. Hematoxylin and eosin staining indicated that NOB increased blood flow and had anti-inflammatory effects. Our findings revealed that NOB improved random skin flap survival.

Endothelium-independent vasodilator effects of nobiletin in rat aorta

Nobiletin is a one of the polymethoxyflavones contained in the peel of citrus fruits, such as Citrus depressa. In this study, the effect of nobiletin-induced relaxation on phenylephrine (PE)-induced contraction of endothelium-denuded rat aorta was investigated. Nobiletin inhibited PE- or KCl-induced contractions in a concentration-dependent manner in endothelium-intact and -denuded aortas. However, this relaxation was stronger in PE-induced contractions than in KCl-induced contractions; moreover, the nobiletin-induced relaxation was significantly increased on PE-induced contraction in endothelium-intact aorta. ODQ significantly inhibited the nobiletin-induced relaxation in endothelium-denuded aorta; however, SQ22536 did not affect the relaxation. In addition, IBMX synergistically enhanced the nobiletin-induced relaxation. Nobiletin increased cGMP levels in aorta. Also, IBMX significantly increased cGMP content in aorta, and ODQ significantly reduced cGMP levels. Nobiletin-induced relaxation was significantly inhibited by the Ca²⁺-activated K⁺ (BK) channel inhibitor iberiotoxin (IbTX) and the ATP-sensitive K⁺ (K_ATP) channel inhibitor glybenclamide. Sodium nitroprusside-induced relaxation was suppressed by IbTX, but not by glybenclamide. These results suggest that nobiletin inhibits PE-induced contractions of endothelium-denuded rat aorta by increasing cGMP levels via GC activation. Moreover, the present findings indicate the possibility that nobiletin opened BK channels by a cGMP-related signal, but K_ATP channels were opened by a cGMP-nonrelated signal in rat aorta.

Estrogen receptor beta signaling inhibits PDGF induced human airway smooth muscle proliferation

Airway smooth muscle (ASM) cell hyperplasia driven by persistent inflammation is a hallmark feature of remodeling in asthma. Sex steroid signaling in the lungs is of considerable interest, given epidemiological data showing more asthma in pre-menopausal women and aging men. Our previous studies demonstrated that estrogen receptor (ER) expression increases in asthmatic human ASM; however, very limited data are available regarding differential roles of ERα vs. ERβ isoforms in human ASM cell proliferation. In this study, we evaluated the effect of selective ERα and ERβ modulators on platelet-derived growth factor (PDGF)-stimulated ASM proliferation and the mechanisms involved. Asthmatic and non-asthmatic primary human ASM cells were treated with PDGF, 17β-estradiol, ERα-agonist and/or ERβ-agonist and/or G-protein-coupled estrogen receptor 30 (GPR30/GPER) agonist and proliferation was measured using MTT and CyQuant assays followed by cell cycle analysis. Transfection of small interfering RNA (siRNA) ERα and ERβ significantly altered the human ASM proliferation. The specificity of siRNA transfection was confirmed by Western blot analysis. Gene and protein expression of cell cycle-related antigens (PCNA and Ki67) and C/EBP were measured by RT-PCR and Western analysis, along with cell signaling proteins. PDGF significantly increased ASM proliferation in non-asthmatic and asthmatic cells. Treatment with PPT showed no significant effect on PDGF-induced proliferation, whereas WAY interestingly suppressed proliferation via inhibition of ERK1/2, Akt, and p38 signaling. PDGF-induced gene expression of PCNA, Ki67 and C/EBP in human ASM was significantly lower in cells pre-treated with WAY. Furthermore, WAY also inhibited PDGF-activated PCNA, C/EBP, cyclin-D1, and cyclin-E. Overall, we demonstrate ER isoform-specific signaling in the context of ASM proliferation. Activation of ERβ can diminish remodeling in human ASM by inhibiting pro-proliferative signaling pathways, and may point to a novel perception for blunting airway remodeling.

Plant-Derived Products for Treatment of Vascular Intima Hyperplasia Selectively Inhibit Vascular Smooth Muscle Cell Functions

Natural products are used widely for preventing intimal hyperplasia (IH), a common cardiovascular disease. Four different cells initiate and progress IH, namely, vascular smooth muscle, adventitial and endothelial cells, and circulation or bone marrow-derived cells. Vascular smooth muscle cells (VSMCs) play a critical role in initiation and development of intimal thickening and formation of neointimal hyperplasia. In this review, we describe the different originating cells involved in vascular IH and emphasize the effect of different natural products on inhibiting abnormal cellular functions, such as VSMC proliferation and migration. We further present a classification for the different natural products like phenols, flavonoids, terpenes, and alkaloids that suppress VSMC growth. Abnormal VSMC physiology involves disturbance in MAPKs, PI3K/AKT, JAK-STAT, FAK, and NF-κB signal pathways. Most of the natural isolate studies have revealed G1/S phase of cell cycle arrest, decreased ROS production, induced cell apoptosis, restrained migration, and downregulated collagen deposition. It is necessary to screen optimal drugs from natural sources that preferentially inhibit VSMC rather than vascular endothelial cell growth to prevent early IH, restenosis following graft implantation, and atherosclerotic diseases.

microRNA-612 is downregulated by platelet-derived growth factor-BB treatment and has inhibitory effects on vascular smooth muscle cell proliferation and migration via directly targeting AKT2

Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) has been implicated in neointimal formation, and therefore is suggested to contribute to arteriosclerosis and restenosis. Previous studies have suggested that some microRNAs (miRs) serve crucial roles in VSMC proliferation and invasion; however, the underlying mechanism remains largely unknown. In the present study, it was demonstrated that treatment with platelet-derived growth factor (PDGF)-BB significantly promoted the proliferation and migration of VSMCs, and decreased miR-612 levels in VSMCs. Overexpression of miR-612 significantly inhibited PDGF-BB-induced migration and invasion of VSMCs, through inducing cell cycle arrest at G1 stage. AKT2 was further identified as a direct target gene of miR-612, and its expression was negatively regulated by miR-612 in VSMCs. Further investigation confirmed that overexpression of miR-612 suppressed the PDGF-BB-induced upregulation of AKT2 protein expression. In conclusion, the present study demonstrated that miR-612 is downregulated by PDGF-BB treatment and has inhibitory effects on VSMC proliferation and migration via targeting AKT2. These findings suggest that miR-612 may be used as a potential therapeutic candidate for neointimal formation in patients with atherosclerosis.

Nobiletin ameliorates isoflurane-induced cognitive impairment via antioxidant, anti-inflammatory and anti-apoptotic effects in aging rats

A recent study reported that nobiletin is an active ingredient in Fructus Aurantii immaturus and Pericarpium Citri Reticulatae, which may be capable of preventing ischemic stroke. Therefore, the present study aimed to determine the neuroprotective effects of nobiletin, and to evaluate whether it could ameliorate isoflurane‑induced cognitive impairment via antioxidant, anti‑inflammatory and anti‑apoptotic effects in aging rats. Male Sprague‑Dawley rats (age, 18 months) were used to analyze the neuroprotective effects of nobiletin. Morris water maze test was used to determine cognitive competence. Enzyme‑linked immunosorbent assay and western blot analysis were also used to quantify nuclear factor‑κB, tumor necrosis factor (TNF)‑α, IL‑1β, IL‑6, glutathione, (GSH), GSH‑peroxidase, superoxide dismutase and malondialdehyde concentration and relevant protein expression levels Cognitive competence was increased in isoflurane-treated rats following treatment with nobiletin. In addition, as expected, nobiletin exerted antioxidant, anti-inflammatory and anti‑apoptotic effects on isoflurane‑induced cognitive impairment in aging rats. Treatment with nobiletin induced the activation of phosphorylated (p)‑Akt, p‑cAMP response element binding protein (CREB) and brain‑derived neurotrophic factor (BDNF) protein expression and reduced the levels of B‑cell lymphoma 2‑associated X protein (Bax) in isoflurane‑induced rats. In conclusion, the present study demonstrated that nobiletin may ameliorate isoflurane-induced cognitive impairment through antioxidant, anti‑inflammatory and anti‑apoptotic effects via modulation of Akt, Bax, p‑CREB and BDNF in aging rats. These findings provide support for the molecular mechanisms underlying the effects of nobiletin treatment on isoflurane-induced damage.

Anti-atherosclerotic plants which modulate the phenotype of vascular smooth muscle cells

BACKGROUND

Cardiovascular disease (CVD) remains the leading cause of global death, with atherosclerosis being a major contributor to this mortality. Several mechanisms are implicated in the pathogenesis of this disease. A key element in the development and progression of atherosclerotic lesions is the phenotype of vascular smooth muscle cells. Under pathophysiologic conditions such as injury, these cells switch from a contractile to a synthetic phenotype that often possesses high proliferative and migratory capacities.

PURPOSE

Despite major advances made in the management and treatment of atherosclerosis, mortality associated with this disease remains high. This mandates that other approaches be sought. Herbal medicine, especially for the treatment of CVD, has been gaining more attention in recent years. This is in no small part due to the evidence-based values associated with the consumption of many plants as well as the relatively cheaper prices, easier access and conventional folk medicine "inherited" over generations. Sections: In this review, we provide a brief introduction about the pathogenesis of atherosclerosis then we highlight the role of vascular smooth muscle cells in this disease, especially when a phenotypic switch of these cells arises. We then thoroughly discuss the various plants that show potentially beneficial effects as anti-atherosclerotic, with prime attention given to herbs and plants that inhibit the phenotypic switch of vascular smooth muscle cells.

CONCLUSION

Accumulating evidence provides the justification for the use of botanicals in the treatment or prevention of atherosclerosis. However, further studies, especially clinical ones, are warranted to better define several pharmacological parameters of these herbs, such as toxicity, tolerability, and efficacy.

The Multifunctional Effects of Nobiletin and Its Metabolites In Vivo and In Vitro

Nobiletin (NOB) chemically known as 5,6,7,8,3′,4′-hexamethoxyflavone is a dietary polymethoxylated flavonoid found in Citrus fruits. Recent evidences show that NOB is a multifunctional pharmaceutical agent. The various pharmacological activities of NOB include neuroprotection, cardiovascular protection, antimetabolic disorder, anticancer, anti-inflammation, and antioxidation. These events may be underpinned by modulation of signaling cascades, including PKA/ERK/MEK/CREB, NF-κB, MAPK, Ca²⁺/CaMKII, PI3K/Akt1/2, HIF-1α, and TGFβ signaling pathways. The metabolites may exhibit stronger beneficial effects than NOB on diseases pathogenesis. The biological activities of NOB have been clarified on many systems. This review aims to discuss the pharmacological effects of NOB with specific mechanisms of actions. NOB may become a promising candidate for potential drug development. However, further investigations of NOB on specific intracellular targets and clinical trials are still needed, especially for in vivo medical applications.

Suppressive effect of formononetin on platelet-derived growth factor-BB-stimulated proliferation and migration of vascular smooth muscle cells

Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) has been implicated in intimal hyperplasia, atherosclerosis and restenosis following percutaneous coronary intervention. Formononetin, a phytoestrogen extracted from the root of Astragalus membranaceus, has been widely used in Chinese tradition medicine due to its protective effects against certain symptoms of cancer, hypertension, inflammation, hypoxia-induced cytotoxicity and ovariectomy-induced bone loss. However, the effect of formononetin on platelet-derived growth factor (PDGF)-BB-induced proliferation and migration of VSMCs, as well as the underlying molecular mechanism, remains largely unclear. In the present study, treatment with formononetin significantly inhibited PDGF-BB-induced proliferation and migration of human VSMCs. Investigation into the underlying molecular mechanism revealed that the administration of formononetin suppressed PDGF-BB-stimulated switch of VSMCs to a proliferative phenotype. Furthermore, treatment with formononetin inhibited the PDGF-BB-induced upregulation of cell cycle-related proteins, matrix metalloproteinase (MMP2) and MMP9. In addition, the that administration of formononetin inhibited the phosphorylation of AKT induced by PDGF-BB in VSMCs. The present results suggest that formononetin has a suppressive effect on PDGF-BB-stimulated VSMCs proliferation and migration, which may occur partly via the inhibition of AKT signaling pathway. Therefore, formononetin may be useful for the treatment of intimal hyperplasia, atherosclerosis and restenosis.

Smooth Muscle Enriched Long Noncoding RNA (SMILR) Regulates Cell Proliferation

BACKGROUND

Phenotypic switching of vascular smooth muscle cells from a contractile to a synthetic state is implicated in diverse vascular pathologies, including atherogenesis, plaque stabilization, and neointimal hyperplasia. However, very little is known about the role of long noncoding RNA (lncRNA) during this process. Here, we investigated a role for lncRNAs in vascular smooth muscle cell biology and pathology.

METHODS AND RESULTS

Using RNA sequencing, we identified >300 lncRNAs whose expression was altered in human saphenous vein vascular smooth muscle cells following stimulation with interleukin-1α and platelet-derived growth factor. We focused on a novel lncRNA (Ensembl: RP11-94A24.1), which we termed smooth muscle-induced lncRNA enhances replication (SMILR). Following stimulation, SMILR expression was increased in both the nucleus and cytoplasm, and was detected in conditioned media. Furthermore, knockdown of SMILR markedly reduced cell proliferation. Mechanistically, we noted that expression of genes proximal to SMILR was also altered by interleukin-1α/platelet-derived growth factor treatment, and HAS2 expression was reduced by SMILR knockdown. In human samples, we observed increased expression of SMILR in unstable atherosclerotic plaques and detected increased levels in plasma from patients with high plasma C-reactive protein.

CONCLUSIONS

These results identify SMILR as a driver of vascular smooth muscle cell proliferation and suggest that modulation of SMILR may be a novel therapeutic strategy to reduce vascular pathologies.

Nanocomplexes from RGD-modified generation 1.0 polyamidoamine based copolymers used for intravascular gene release to prevent restenosis

Aim: To validate the efficacy of nanocomplexes from RGD-modified polyamidoamine (PAMAM G1) copolymer for prevention of restenosis. Materials & methods: Generation 1.0 polyamidoamine (PAMAM G1)-based copolymers (PGP) and RGD modified PGP (PGP-RGD) were synthesized and its properties were evaluated. Intravascular VEGF165 release tests were performed. Results: The PGP-RGD1 (2.6% grafting rate) exhibited lower cytotoxicity and larger combining ability with pDNA. The complexes had sizes of 80–160 nm and zeta potentials of 3–20 mV. Transfection efficiency of PGP-RGD1 complexes in human umbilical vein endothelial cells was larger than that of PGP complexes. Patency and expression level of artery in PGP-RGD1 group were higher than that in saline group. Conclusion: PGP-RGD1 will be a promising targeted gene vector.