The benefit of docosahexanoic acid on the migration of vascular smooth muscle cells is partially dependent on Notch regulation of MMP-2/-9

"How to Release or Not Release, That Is the Question." A Review of Interleukin-1 Cellular Release Mechanisms in Vascular Inflammation

Cardiovascular disease remains the leading cause of death worldwide, characterized by atherosclerotic activity within large and medium-sized arteries. Inflammation has been shown to be a primary driver of atherosclerotic plaque formation, with interleukin-1 (IL-1) having a principal role. This review focuses on the current state of knowledge of molecular mechanisms of IL-1 release from cells in atherosclerotic plaques. A more in-depth understanding of the process of IL-1's release into the vascular environment is necessary for the treatment of inflammatory disease processes, as the current selection of medicines being used primarily target IL-1 after it has been released. IL-1 is secreted by several heterogenous mechanisms, some of which are cell type-specific and could provide further specialized targets for therapeutic intervention. A major unmet challenge is to understand the mechanism before and leading to IL-1 release, especially by cells in atherosclerotic plaques, including endothelial cells, vascular smooth muscle cells, and macrophages. Data so far indicate a heterogeneity of IL-1 release mechanisms that vary according to cell type and are stimulus-dependent. Unraveling this complexity may reveal new targets to block excess vascular inflammation.

Tongxinluo promotes endothelium-dependent arteriogenesis to attenuate diabetic peripheral arterial disease

BACKGROUND

Peripheral arterial disease (PAD) has become one of the leading causes of disa-bility and death in diabetic patients. Restoring blood supply to the hindlimbs, especially by promoting arteriogenesis, is currently the most effective strategy, in which endothelial cells play an important role. Tongxinluo (TXL) has been widely used for the treatment of cardio-cerebrovascular diseases and extended for diabetes-related vascular disease.

AIM

To investigate the effect of TXL on diabetic PAD and its underlying mechanisms.

METHODS

An animal model of diabetic PAD was established by ligating the femoral artery of db/db mice. Laser Doppler imaging and micro-computed tomography (micro-CT) were performed to assess the recovery of blood flow and arteriogenesis. Endothelial cell function related to arteriogenesis and cellular pyroptosis was assessed using histopathology, Western blot analysis, enzyme-linked immuno-sorbent assay and real-time polymerase chain reaction assays. In vitro, human vascular endothelial cells (HUVECs) and human vascular smooth muscle cells (VSMCs) were pretreated with TXL for 4 h, followed by incubation in high glucose and hypoxia conditions to induce cell injury. Then, indicators of HUVEC pyroptosis and function, HUVEC-VSMC interactions and the migration of VSMCs were measured.

RESULTS

Laser Doppler imaging and micro-CT showed that TXL restored blood flow to the hindlimbs and enhanced arteriogenesis. TXL also inhibited endothelial cell pyroptosis via the reactive oxygen species/nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3/Caspase-1/GSDMD signaling pathway. In addition, TXL restored endothelial cell functions, including maintaining the balance of vasodilation, acting as a barrier to reduce inflammation, and enhancing endothelial-smooth muscle cell interactions through the Jagged-1/Notch-1/ephrin-B2 signaling pathway. Similar results were observed in vitro.

CONCLUSION

TXL has a pro-arteriogenic effect in the treatment of diabetic PAD, and the mechanism may be related to the inhibition of endothelial cell pyroptosis, restoration of endothelial cell function and promotion of endothelial cell-smooth muscle cell interactions.

Development of Neovasculature in Axially Vascularized Calcium Phosphate Cement Scaffolds

Augmenting the vascular supply to generate new tissues, a crucial aspect in regenerative medicine, has been challenging. Recently, our group showed that calcium phosphate can induce the formation of a functional neo-angiosome without the need for microsurgical arterial anastomosis. This was a preclinical proof of concept for biomaterial-induced luminal sprouting of large-diameter vessels. In this study, we investigated if sprouting was a general response to surgical injury or placement of an inorganic construct around the vessel. Cylindrical biocement scaffolds of differing chemistries were placed around the femoral vein. A contrast agent was used to visualize vessel ingrowth into the scaffolds. Cell populations in the scaffold were mapped using immunohistochemistry. Calcium phosphate scaffolds induced 2.7-3 times greater volume of blood vessels than calcium sulphate or magnesium phosphate scaffolds. Macrophage and vSMC populations were identified that changed spatially and temporally within the scaffold during implantation. NLRP3 inflammasome activation peaked at weeks 2 and 4 and then declined; however, IL-1β expression was sustained over the course of the experiment. IL-8, a promoter of angiogenesis, was also detected, and together, these responses suggest a role of sterile inflammation. Unexpectedly, the effect was distinct from an injury response as a result of surgical placement and also was not simply a foreign body reaction as a result of placing a rigid bioceramic next to a vein, since, while the materials tested had similar microstructures, only the calcium phosphates tested elicited an angiogenic response. This finding then reveals a potential path towards a new strategy for creating better pro-regenerative biomaterials.

Short-Term Omega-3 Supplementation Modulates Novel Neurovascular and Fatty Acid Metabolic Proteome Changes in the Retina and Ophthalmic Artery of Mice with Targeted Cyp2c44 Gene Deletion

Cytochrome P450 (CYP) gene mutations are a common predisposition associated with glaucoma. Although the molecular mechanisms are largely unknown, omega-3 polyunsaturated fatty acids (ω-3 PUFA) and their CYP-derived bioactive mediators play crucial roles in the ocular system. Here, we elucidated the proteome and cell-signalling alterations attributed to the main human CYP2C gene deficiency using a homologous murine model (Cyp2c44^−/−), and unravelled the effects of acute ω-3 PUFA supplementation in two ocular vascular beds comprising the retrobulbar ophthalmic artery (OA) and retina (R). Male Cyp2c44^−/− mice (KO) and their floxed littermates (WT) were gavaged daily for 7 days with 0.01 mL/g of ω-3 PUFA composed of menhaden fish oil. Another group in respective strains served as vehicle-treated controls. OA and R were isolated at day 8 post-treatment (n = 9/group) and subjected to mass spectrometry (MS)-based proteomics and in silico bioinformatics analyses. Cyp2c44^−/− resulted in significant detrimental proteome changes associated with compromised vascular integrity and degeneration in the OA and R, respectively. However, notable changes in the OA after ω-3 PUFA intake were associated with the maintenance of intercellular junctional and endothelial cell functions, as well as activation of the fatty acid metabolic pathway in the KO mice. Conversely, ω-3 PUFA supplementation profoundly influenced the regulation of a large majority of retinal proteins involved in the preservation of neuronal and phototransduction activities in WT mice, namely synaptophysin, phosducin and guanylate cyclase-1, while significantly abrogating degenerative processes in the KO mice via the regulation of, namely, synaptotagmin-1 and beta-crystallin B2. In gist, this study demonstrated that dietary supplementation with ω-3 PUFA for a short period of seven days regulated specific neuro-vasculoprotective mechanisms to preserve the functionality of the OA and R in the absence of Cyp2c44. The potential adjunct use of ω-3 PUFA for glaucoma therapy needs further investigation.

Antioxidant Polyphenols of Antirhea borbonica Medicinal Plant and Caffeic Acid Reduce Cerebrovascular, Inflammatory and Metabolic Disorders Aggravated by High-Fat Diet-Induced Obesity in a Mouse Model of Stroke

Metabolic disorders related to obesity and type 2 diabetes are associated with aggravated cerebrovascular damages during stroke. In particular, hyperglycemia alters redox and inflammatory status, leading to cerebral endothelial cell dysfunction, blood–brain barrier (BBB) disruption and brain homeostasis loss. Polyphenols constitute the most abundant dietary antioxidants and exert anti-inflammatory effects that may improve cerebrovascular complications in stroke. This study evaluated the effects of the characterized polyphenol-rich extract of Antirhea borbonica medicinal plant and its major constituent caffeic acid on a high-fat diet (HFD)-induced obesity mouse model during ischemic stroke, and murine bEnd3 cerebral endothelial cells in high glucose condition. In vivo, polyphenols administered by oral gavage for 12 weeks attenuated insulin resistance, hyperglycemia, hyperinsulinemia and dyslipidemia caused by HFD-induced obesity. Polyphenols limited brain infarct, hemorrhagic transformation and BBB disruption aggravated by obesity during stroke. Polyphenols exhibited anti-inflammatory and antioxidant properties by reducing IL-1β, IL-6, MCP-1, TNF-α and Nrf2 overproduction as well as total SOD activity elevation at the cerebral or peripheral levels in obese mice. In vitro, polyphenols decreased MMP-2 activity that correlated with MCP-1 secretion and ROS intracellular levels in hyperglycemic condition. Protective effects of polyphenols were linked to their bioavailability with evidence for circulating metabolites including caffeic acid, quercetin and hippuric acid. Altogether, these findings show that antioxidant polyphenols reduced cerebrovascular, inflammatory and metabolic disorders aggravated by obesity in a mouse model of stroke. It will be relevant to assess polyphenol-based strategies to improve the clinical consequences of stroke in the context of obesity and diabetes.

Novel Therapeutical Approaches to Managing Atherosclerotic Risk

Atherosclerosis is a multifactorial vascular disease that leads to inflammation and stiffening of the arteries and decreases their elasticity due to the accumulation of calcium, small dense Low Density Lipoproteins (sdLDL), inflammatory cells, and fibrotic material. A review of studies pertaining to cardiometabolic risk factors, lipids alterations, hypolipidemic agents, nutraceuticals, hypoglycaemic drugs, atherosclerosis, endothelial dysfunction, and inflammation was performed. There are several therapeutic strategies including Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) inhibitors, inclisiran, bempedoic acid, Glucagon-Like Peptide-1 Receptor agonists (GLP-1 RAs), and nutraceuticals that promise improvement in the atheromatous plaque from a molecular point of view, because have actions on the exposure of the LDL-Receptor (LDL-R), on endothelial dysfunction, activation of macrophages, on lipid oxidation, formations on foam cells, and deposition extracellular lipids. Atheroma plaque reduction both as a result of LDL-Cholesterol (LDL-C) intensive lowering and reducing inflammation and other residual risk factors is an integral part of the management of atherosclerotic disease, and the use of valid therapeutic alternatives appear to be appealing avenues to solving the problem.

Caveolin‑1 modulates hypertensive vascular remodeling via regulation of the Notch pathway

Hypertension is one of the critical risk factors of cerebrovascular disease. Caveolin-1 (Cav-1) has been suggested to be involved in the development of hypertension; however, the underlying mechanism remains largely unknown. Therefore, the present study aimed to investigate the mechanism underlying Cav-1 in hypertension. In the present study, the hypertension model was induced by infusion of angiotensin II (Ang-II) in rats. Cell Counting Kit-8 assay was used to detect the viability of human umbilical vein endothelial cells (HUVECs). Flow cytometry was used to determine the apoptosis of HUVECs. Transmission electron microscopy was utilized to address the thickness of the vessel walls. Reverse transcription-quantitative PCR, western blotting and immunofluorescence staining were used to assess the mechanism of cav-1/Notch1 involved in hypertensive vascular remodeling. In the present study, an Ang-II-induced hypertension model was successfully established in rats. With this model, it was found that the expression levels of cav-1 and Notch1 were significantly increased in brain tissues in the hypertension group compared with the sham-operated group. In cultured HUVECs, knockdown of cav-1 regulated Ang-II-induced HUVEC viability and apoptosis, and modulated hypertensive vascular remodeling, which was mediated by the Notch pathway. The data of the present study demonstrated that the cav-1/Notch signaling plays an important role in the regulation of Ang-II-induced hypertension and vascular remodeling.

Docosahexaenoic acid inhibits vascular smooth muscle cell migration and proliferation by decreasing microRNA‑155 expression levels

Vascular smooth muscle cell (VSMC) hyperplasia is a common cause of carotid restenosis. In the present study, the potential protective effects of docosahexaenoic acid (DHA) in carotid restenosis and the underlying mechanism of its effects were examined. VSMCs were treated with DHA, a polyunsaturated ω-3 fatty acid. Cell migration and proliferation were assessed using wound healing and Cell Counting Kit-8 assays and by measuring Ki-67 protein levels. Additionally, the expression levels of microRNA-155 were determined by reverse transcription-quantitative PCR (RT-qPCR). The involvement of microRNA-155 in the regulation of migration and proliferation was evaluated by transfecting VSMCs with microRNA mimics and inhibitors. Moreover, the reversal of migration and proliferation after transfection of VSMCs with the microRNA mimics and subsequent treatment with DHA was investigated. A target gene of microRNA-155 was identified using RT-qPCR and luciferase assays. The migration and proliferation of VSMCs, as well as the expression of microRNA-155 was inhibited by DHA stimulation. MicroRNA-155 regulated the migration and proliferation of VSMCs. Finally, proliferation and migration of VSMCs were reduced following DHA treatment, which was mediated by an increase in the expression levels of microRNA-155. Suppressor of cytokine signalling 1 (Socs1) was the target gene of microRNA-155. In conclusion, DHA inhibited VSMC migration and proliferation by reducing microRNA-155 expression. This effect may be caused by the microRNA-155 target gene Socs1.

Protective effect of Soluble Epoxide Hydrolase Inhibition in Retinal Vasculopathy associated with Polycystic Kidney Disease

Rationale: Vasoregression secondary to glial activation develops in various retinal diseases, including retinal degeneration and diabetic retinopathy. Photoreceptor degeneration and subsequent retinal vasoregression, characterized by pericyte loss and acellular capillary formation in the absence diabetes, are also seen in transgenic rats expressing the polycystic kidney disease (PKD) gene. Activated Müller glia contributes to retinal vasodegeneration, at least in part via the expression of the soluble epoxide hydrolase (sEH). Given that an increase in sEH expression triggered vascular destabilization in diabetes, and that vasoregression is similar in diabetic mice and PKD rats, the aim of the present study was to determine whether sEH inhibition could prevent retinal vasoregression in the PKD rat.

Methods: One-month old male homozygous transgenic PKD rats were randomly allocated to receive vehicle or a sEH inhibitor (sEH-I; Sar5399, 30 mg/kg) for four weeks. Wild-type Sprague-Dawley (SD) littermates received vehicle as controls. Retinal sEH expression and activity were measured by Western blotting and LC-MS, and vasoregression was quantified in retinal digestion preparations. Microglial activation and immune response cytokines were assessed by immunofluorescence and quantitative PCR, respectively. 19,20-dihydroxydocosapentaenoic acid (19,20-DHDP) mediated Notch signaling, microglial activation and migration were assessed in vivo and in vitro.

Results: This study demonstrates that sEH expression and activity were increased in PKD retinae, which led to elevated production of 19,20-DHDP and the depression of Notch signaling. The latter changes elicited pericyte loss and the recruitment of CD11b⁺/CD74⁺ microglia to the perivascular region. Microglial activation increased the expression of immune-response cytokines, and reduced levels of Notch3 and delta-like ligand 4 (Dll4). Treatment with Sar5399 decreased 19,20-DHDP generation and increased Notch3 expression. Sar5399 also prevented vasoregression by reducing pericyte loss and suppressed microglial activation as well as the expression of immune-response cytokines. Mechanistically, the activation of Notch signaling by Dll4 maintained a quiescent microglial cell phenotype, i.e. reduced both the surface presentation of CD74 and microglial migration. In contrast, in retinal explants, 19,20-DHDP and Notch inhibition both promoted CD74 expression and reversed the Dll4-induced decrease in migration.

Conclusions: Our data indicate that 19,20-DHDP-induced alterations in Notch-signaling result in microglia activation and pericyte loss and contribute to retinal vasoregression in polycystic kidney disease. Moreover, sEH inhibition can ameliorate vasoregression through reduced activity of inflammatory microglia. sEH inhibition is thus an attractive new therapeutic approach to prevent retinal vasoregression.

FOXC2-AS1 regulates phenotypic transition, proliferation and migration of human great saphenous vein smooth muscle cells

Objectives

In varicose veins, vascular smooth muscle cells (VSMCs) often shows phenotypic transition and abnormal proliferation and migration. Evidence suggests the FOXC2–Notch pathway may be involved in the pathogenesis of varicose veins. Here, this study aimed to explore the role of long non-coding RNA FOXC2-AS1 (FOXC2 antisense RNA 1) in phenotypic transition, proliferation, and migration of varicose vein-derived VSMCs and to explore whether the FOXC2-Notch pathway was involved in this process.

Methods

The effect of FOXC2-AS1 on the proliferation and migration of human great saphenous vein smooth muscle cells (SV-SMCs) was analyzed using MTT assay and Transwell migration assay, respectively. The levels of contractile marker SM22α and synthetic marker osteopontin were measured by immunohistochemistry and Western blot to assess the phenotypic transition.

Results

The human varicose veins showed thickened intima, media and adventitia layers, increased synthetic VSMCs, as well as upregulated FOXC2-AS1 and FOXC2 expression. In vitro assays showed that FOXC2-AS1 overexpression promoted phenotypic transition, proliferation, and migration of SV-SMCs. However, the effect of FOXC2-AS1 overexpression could be abrogated by both FOXC2 silencing and the Notch signaling inhibitor FLI-06. Furthermore, FOXC2-AS1 overexpression activated the Notch pathway by upregulating FOXC2.

Conclusion

FOXC2-AS1 overexpression promotes phenotypic transition, proliferation, and migration of SV-SMCs, at least partially, by activating the FOXC2-Notch pathway.

The resolution of inflammation through omega-3 fatty acids in atherosclerosis, intimal hyperplasia, and vascular calcification

Omega-3 fatty acids serve as the substrate for the formation of a group of lipid mediators that mediate the resolution of inflammation. The cardiovascular inflammatory response in atherosclerosis and vascular injury is characterized by a failure in the resolution of inflammation, resulting in a chronic inflammatory response. The proresolving lipid mediator resolvin E1 (RvE1) is formed by enzymatic conversion of the omega-3 fatty acid eicosapentaenoic acid (EPA), and signals resolution of inflammation through its receptor ChemR23. Importantly, the resolution of cardiovascular inflammation is an active, multifactorial process that involves modulation of the immune response, direct actions on the vascular wall, as well as close interactions between macrophages and vascular smooth muscle cells. Promoting anti-atherogenic signalling through the stimulation of endogenous resolution of inflammation pathways may provide a novel therapeutic strategy in cardiovascular prevention.

The Use of Nutraceuticals to Counteract Atherosclerosis: The Role of the Notch Pathway

Despite the currently available pharmacotherapies, today, thirty percent of worldwide deaths are due to cardiovascular diseases (CVDs), whose primary cause is atherosclerosis, an inflammatory disorder characterized by the buildup of lipid deposits on the inside of arteries. Multiple cellular signaling pathways have been shown to be involved in the processes underlying atherosclerosis, and evidence has been accumulating for the crucial role of Notch receptors in regulating the functions of the diverse cell types involved in atherosclerosis onset and progression. Several classes of nutraceuticals have potential benefits for the prevention and treatment of atherosclerosis and CVDs, some of which could in part be due to their ability to modulate the Notch pathway. In this review, we summarize the current state of knowledge on the role of Notch in vascular health and its modulation by nutraceuticals for the prevention of atherosclerosis and/or treatment of related CVDs.

Numb inhibits epithelial-mesenchymal transition via RBP-Jκ-dependent Notch1/PTEN/FAK signaling pathway in tongue cancer

BACKGROUND

Oral cancer has been estimated as the sixth most frequent solid cancer all over the world, in which tongue squamous cell carcinoma (TSCC) is the most common type of oral cancers. However, the mechanism of TSCC metastasizing to lymph node and distant sites has not been completely understood.

METHODS

In this study, RT-qPCR method was used to detect the mRNA level of Numb, PTEN and Notch1 genes, as well as EMT-associated genes. Western blot assay was utilized to detect protein level of these genes. In addition, we determined cell proliferation by MTT assay and employed transwell invasion assay and wound healing assay to probe the abilities of invasion and migration, respectively. To investigate the role of PTEN, its inhibitor VO-Ohpic trihydrate was used to treat SCC-4 and CAL27 cells.

RESULTS

We found that Numb expression was downregulated in SCC-9 and CAL-27 cells compared to NHOK cells. Instead, Notch1 level in SCC-9 and CAL-27 cells were higher than that in NHOK cells. Furthermore, the results showed that Numb overexpression significantly suppressed proliferation, migration and invasion of SCC-9 and CAL-27 cells via regulating Notch1 signaling and EMT-related genes expression. By contrast, we observed that RBP-Jκ knockdown had an inhibitory role in proliferation, migration and invasion of SCC-9 and CAL-27 cells. In cells with Numb overexpression or RBP-Jκ knockdown, p-FAK and EMT-related genes were remarkably regulated.

CONCLUSIONS

Our findings provide new mechanism of understanding the metastasis of TSCC and help develop therapeutic strategies for treating tongue cancer.

Modification of α2,6-sialylation mediates the invasiveness and tumorigenicity of non-small cell lung cancer cells in vitro and in vivo via Notch1/Hes1/MMPs pathway

The alterations of sialylation on cell surface N-glycans due to overexpression of different sialyltransferases play a vital role in tumorigenesis and tumor progression. The β-galactoside α2-6-sialyltransferase 1 (ST6Gal-I) has been reported to be highly expressed in several cancers, including breast cancer, hepatocellular cancer and colon carcinoma. However, the roles and underlying mechanisms of ST6Gal-I in non-small cell lung cancer (NSCLC) still need to be elucidated. In this study, we determined that mRNA levels of ST3GAL1, ST6GALNAC3 and ST8SIA6 were remarkably reduced in lung cancer tissues and cells, whereas ST6GAL1 level significantly increased. The mRNA, protein and glycan levels of ST6Gal-I were higher in lung cancer tissues and cells. Moreover, down-regulation of ST6Gal-I decreased protein levels of Jagged1, DLL-1, Notch1, Hes1, Hey1, matrix-metalloproteinases (MMPs) and VEGF, and suppressed proliferation, migration and invasion capabilities of A549 and H1299 cells in vitro. In vivo, ST6Gal-I silencing suppressed tumorigenicity of NSCLC cells in athymic nude mice via the Notch1/Hes1/MMPs pathway. In addition, overexpression of Notch1 rescued the reduced growth and metastasis of A549 and H1299 cells resulted by ST6Gal-I silencing. Modification of α2,6-sialylation positively associates with lung cancer progression, thereby indicating that ST6Gal-I may mediate the invasiveness and tumorigenicity of NSCLC cells via the Notch1/Hes1/MMPs pathway both in vitro and in vivo. Thus, our results provide a novel therapeutic approach for blocking metastasis in lung cancer patients.

Docosahexaenoic acid suppresses angiotensin II-induced A7r5 vascular smooth muscle cell proliferation and migration under pulsatile pressure stress

Elevated mechanical stress applied to vascular walls is well known to modulate vascular remodeling and plays a part in the pathogenesis of atherosclerosis. On the other hand, docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid, has been shown to protect against several types of cardiovascular diseases including atherosclerosis and hypertension. The aim of this study was to clarify the effect of pulsatile pressure stress and DHA on angiotensin II-induced proliferation and migration in A7r5 vascular smooth muscle cells (VSMCs). Pulsatile pressure of between 80 and 160 mmHg was repeatedly applied to VSMCs at a frequency of 4 cycles per min using an apparatus that we developed. Cell proliferation and migration were evaluated using a live cell movie analyzer. Application of pulsatile pressure stress for 24 h significantly increased cell proliferation. Angiotensin II also significantly increased cell proliferation in the presence or absence of pressure stress. DHA significantly inhibited angiotensin II-induced cell proliferation regardless of the pressure load. Angiotensin II significantly induced cell migration regardless of the pulsatile pressure load. Pulsatile pressure stress alone slightly, but not significantly, induced cell migration. DHA inhibited angiotensin II-induced VSMC proliferation and migration under abnormal pressure conditions. Pressure stress tended to induce extracellular signal-regulated kinase (ERK) phosphorylation in the absence of angiotensin II, whereas it significantly induced ERK phosphorylation in the presence of angiotensin II. However, the pressure-induced ERK phosphorylation was not observed in the DHA-treated VSMCs. Our findings may contribute to the understanding of the beneficial effect of DHA on various cardiovascular disorders.

MiR-29b mimics promotes cell apoptosis of smooth muscle cells via targeting on MMP-2

The phenotypic transformation and dysfunctions of vascular smooth muscle cells (SMCs) such as abnormality proliferation and apoptosis are key pathological basis of atherosclerosis. The recent study aimed to detect the role of miR-29b in phenotypic transformation of SMCs. In this study, we investigated the expression level of miR-29b and MMP-2 in acute coronary syndrome (ACS) patients, verified whether MMP-2 is the target gene of miR-29b by luciferase reporter gene system, and explored the role of miR-29b in the viability and apoptosis of SMCs. We found that the plasma level of miR-29b was significantly downregulated to 56% of controls (p < 0.01). The plasma level of MMP-2 in health controls was 34.9 ± 6.9 ng/mL, and that it significantly increased to 46.2 ± 13.2 ng/mL in ACS patients. MMP-2 is a target gene of miR-29b. The overexpression of miR-29b significantly downregulated the expression of MMP-2 mRNA and protein. miR-29b mimics inhibited the cell viability of SMCs, and cell apoptosis was significantly enhanced compared with the NC group, especially in the early stage. In the presence of MMP-2 inhibitor SB-3CT, the cell viability and apoptosis of SMC cells were significantly reduced and enhanced, respectively, while the miR-29b -inhibited cell viability and -induced cell apoptosis were not significantly changed. Taken together, miR-29b was downregulated in ACS patients. MiR-29 mimics inhibits cell viability and promotes cell apoptosis via directly targeting on MMP-2, which could be a potentially promising therapy target for cardiovascular diseases.

Comparison of trans-fatty acids on proliferation and migration of vascular smooth muscle cells

Consumption of trans-fatty acids has been linked to an increased risk of cardiovascular diseases, such as atherosclerosis. Milk and dairy products contain trans-fatty acids, such as transvaccenic acid (TVA) and conjugated linoleic acid (CLA). Although artificially hydrogenated trans-fatty acids (e.g., elaidic acid (EA)) are known to induce atherosclerosis, it is unclear whether ruminant trans-fats, such as TVA, are associated with such diseases. Therefore, we investigated the effects of TVA on vascular smooth muscle cells (VSMCs). VSMCs were treated with TVA, CLA, and EA at 0-100 μM for 24 h. Cell proliferation and migration increased upon treatment with EA, not with TVA and CLA. EA increased protein expression of proliferation-associated proteins (cyclin-dependent kinase 4 (CDK4) and cyclin D1), while TVA and CLA decreased CDK4 expression. These results suggest that TVA is not as risky as other trans-fatty acids such as EA in the vascular system.

Activation of an endothelial Notch1-Jagged1 circuit induces VCAM1 expression, an effect amplified by interleukin-1β

The Notch1 and Notch4 signaling pathways regulate endothelial cell homeostasis. Inflammatory cytokines induce the expression of endothelial adhesion molecules, including VCAM1, partly by downregulating Notch4 signaling. We investigated the role of endothelial Notch1 in this IL-1β-mediated process. Brief treatment with IL-1β upregulated endothelial VCAM1 and Notch ligand Jagged1. IL-1β decreased Notch1 mRNA levels, but levels of the active Notch1ICD protein remained constant. IL-1β-mediated VCAM1 induction was downregulated in endothelial cells subjected to pretreatment with a pharmacological inhibitor of the γ-secretase, which activates Notch receptors, producing NotchICD. It was also downregulated in cells in which Notch1 and/or Jagged1 were silenced.Conversely, the forced expression of Notch1ICD in naïve endothelial cells upregulated VCAM1 per se and amplified IL-1β-mediated VCAM1 induction. Jagged1 levels increased and Notch4 signaling was downregulated in parallel. Finally, Notch1ICD and Jagged1 expression was upregulated in the endothelium of the liver in a model of chronic liver inflammation.In conclusion, we describe here a cell-autonomous, pro-inflammatory endothelial Notch1-Jagged1 circuit (i) triggering the expression of VCAM1 even in the absence of inflammatory cytokines and (ii) enhancing the effects of IL-1β. Thus, IL-1β regulates Notch1 and Notch4 activity in opposite directions, consistent with a selective targeting of Notch1 in inflamed endothelium.

Notch Signaling in Vascular Smooth Muscle Cells

The Notch signaling pathway is a highly conserved pathway involved in cell fate determination in embryonic development and also functions in the regulation of physiological processes in several systems. It plays an especially important role in vascular development and physiology by influencing angiogenesis, vessel patterning, arterial/venous specification, and vascular smooth muscle biology. Aberrant or dysregulated Notch signaling is the cause of or a contributing factor to many vascular disorders, including inherited vascular diseases, such as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, associated with degeneration of the smooth muscle layer in cerebral arteries. Like most signaling pathways, the Notch signaling axis is influenced by complex interactions with mediators of other signaling pathways. This complexity is also compounded by different members of the Notch family having both overlapping and unique functions. Thus, it is vital to fully understand the roles and interactions of each Notch family member in order to effectively and specifically target their exact contributions to vascular disease. In this chapter, we will review the Notch signaling pathway in vascular smooth muscle cells as it relates to vascular development and human disease.

Infusion of docosahexaenoic acid protects against myocardial infarction

Most of the cardioprotective effects of long-chain omega 3 fatty acids, namely docosahexaenoic (DHA; 22:6n-3) and eicosapentaenoic (EPA; 20:5n-3), are due to their hypotriglyceridemic and anti-inflammatory effects, which lower the risk for cardiovascular disease and myocardial infarction. Little is known on the direct preventive activities of DHA and EPA on heart function. In isolated hearts, we studied (1) whether infused DHA is able to protect the heart from ischemia/reperfusion damage and (2) the role played by Notch-mediated signal transduction pathways in myocardial infarction. Perfusion with DHA before and before/after induction of ischemia reperfusion significantly diminished cardiac damage and afforded antioxidant protection. Mechanistically, infusion of DHA before and before/after the induction of ischemia differentially modulated the expression of Notch2 and 3 target genes. In particular, DHA increased the expression of Hey1 when infused pre- and pre/post-ischemia; Jagged 1 and the Notch2 receptors increased with DHA pre-ischemia, but not pre/post; Notch2 and 3 receptors as well as Delta increased following DHA administration pre- and (especially) pre/post-ischemia. In conclusion, while the precise nature of the Notch-mediated protection from ischemia/reperfusion afforded by DHA is as yet to be fully elucidated, our data add to the growing body of literature that indicates how systemic administration of DHA provides cardiovascular protection.

Association of serum phospholipid PUFAs with cardiometabolic risk: beneficial effect of DHA on the suppression of vascular proliferation/inflammation

OBJECTIVES

Blood or dietary polyunsaturated fatty acids (PUFAs), particularly ω3-PUFAs were known for cardiovascular protective effect. However, the results are still controversial. We aimed to investigate the association of serum phospholipid PUFAs with cardiometabolic risk through cross-sectional/experimental studies.

DESIGN/METHODS

Serum phospholipid FA compositions and cardiometabolic risk parameters were measured in controls [healthy: n=987, metabolic syndrome (MetS): n=214] and CAD patients (CAD-only: n=152, CAD+MetS: n=56). Experimental assays were performed in vascular smooth muscle cells (VSMCs).

RESULTS

Major cardiometabolic risk markers, i.e. insulin resistance, hs-C-reactive proteins, and malondialdehyde were higher, and adiponectin and LDL particle size were lower in CAD patients, particularly those with MetS than in healthy controls. Serum linoleic acid (LA, C18:2ω-6) was lowest and dihomo-γ-linolenic acids (DGLAs, C20:3ω-6) were highest in CAD patients with MetS among the 4 groups. Docosahexaenoic acid (DHA, C22:6ω-3) was lower and arachidonic acid (AA, C20:4ω-6) and ω6/ω3-PUFAs were higher in CAD patients than in controls. ω3-PUFAs were significantly lower in CAD patients, particularly those with MetS than in healthy controls. Multiple regression analysis revealed that AA and DHA among serum FAs were mainly associated with the cardiometabolic risk (β'-coefficients for AA:0.336; DHA: -0.296) together with age, MetS factors, LA, DGLA and gender (r=0.529, p<0.001). Under LPS-induced stress condition, LA and DHA significantly suppressed VSMC proliferation. DHA also up-regulated the phosphorylation of p38 and ERK, and dramatically inhibited nuclear translocation of NF-κB-p65 in VSMCs.

CONCLUSION

AA and DHA were mainly associated with cardiometabolic risk. Particularly, DHA may be effective on suppression of vascular proliferation and inflammation.

Müller glia cells regulate Notch signaling and retinal angiogenesis via the generation of 19,20-dihydroxydocosapentaenoic acid

Cytochrome P450 (CYP) epoxygenases generate bioactive lipid epoxides which can be further metabolized to supposedly less active diols by the soluble epoxide hydrolase (sEH). As the role of epoxides and diols in angiogenesis is unclear, we compared retinal vasculature development in wild-type and sEH(-/-) mice. Deletion of the sEH significantly delayed angiogenesis, tip cell, and filopodia formation, a phenomenon associated with activation of the Notch signaling pathway. In the retina, sEH was localized in Müller glia cells, and Müller cell-specific sEH deletion reproduced the sEH(-/-) retinal phenotype. Lipid profiling revealed that sEH deletion decreased retinal and Müller cell levels of 19,20-dihydroxydocosapentaenoic acid (DHDP), a diol of docosahexenoic acid (DHA). 19,20-DHDP suppressed endothelial Notch signaling in vitro via inhibition of the γ-secretase and the redistribution of presenilin 1 from lipid rafts. Moreover, 19,20-DHDP, but not the parent epoxide, was able to rescue the defective angiogenesis in sEH(-/-) mice as well as in animals lacking the Fbxw7 ubiquitin ligase, which demonstrate strong basal activity of the Notch signaling cascade. These studies demonstrate that retinal angiogenesis is regulated by a novel form of neuroretina-vascular interaction involving the sEH-dependent generation of a diol of DHA in Müller cells.

The role of Notch pathway in cardiovascular diseases

The recent increase in human lifespan, coupled with unhealthy diets and lifestyles have led to an unprecedented increase in cardiovascular diseases. Even in the presence of a wide range of therapeutic options with variable efficacy, mortality due to heart failure is still high and there is a need to identify new therapeutic targets. Genetic and in vitro studies have implicated the Notch signalling in the development and maintenance of the cardiovascular system through a direct effect on biological functions of vascular cells (endothelial and vascular smooth muscle cells) and cardiomyocytes. Notch signalling is also involved in the modulation of inflammation, which plays a major role in causing and exacerbating cardiovascular diseases. The Notch pathway could represent a new therapeutic target for the treatment of cardiovascular diseases.

Inhibition of matrix metalloproteinase-9 expression by docosahexaenoic acid mediated by heme oxygenase 1 in 12-O-tetradecanoylphorbol-13-acetate-induced MCF-7 human breast cancer cells

Matrix metalloproteinase-9 (MMP-9) plays a crucial role in tumor metastasis. Previous studies showed that polyunsaturated fatty acids exhibit an anti-cancer effect in various human carcinoma cells, but the effect of docosahexaenoic acid (DHA) and linoleic acid (LA) on metastasis of breast cancer cells is not fully clarified. We studied the anti-metastasis potential of DHA and LA in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MCF-7 cells. We found that TPA (100 ng/ml) induced MMP-9 enzyme activity both dose- and time-dependently, and 200 μM DHA and LA significantly inhibited MMP-9 mRNA and protein expression, enzyme activity, cell migration, and invasion. Treatment with PD98059 (10 μM), wortmannin (10 μM), and GF109203X (0.5 μM) decreased TPA-induced MMP-9 protein expression and enzyme activity. TPA-induced activation of ERK1, Akt, and PKCδ was attenuated by DHA, whereas LA attenuated only ERK1 activation. GF109203X also suppressed ERK1 activation. EMSA showed that DHA, LA, PD98059, and wortmannin decreased TPA-induced NF-κB and AP-1 DNA-binding activity. Furthermore, DHA rather than LA dose-dependently increased HO-1 expression. HO-1 siRNA alleviated the inhibition by DHA of TPA-induced MMP-9 protein expression and enzyme activity in MCF-7 cells, and HO-1 knockdown reversed the DHA inhibition of cell migration. These results suggest that DHA and LA have both similar and divergent signaling pathways in the suppression of TPA-induced MCF-7 metastasis.

Downregulation of the Notch signaling pathway inhibits hepatocellular carcinoma cell invasion by inactivation of matrix metalloproteinase-2 and -9 and vascular endothelial growth factor

Hepatocellular carcinoma (HCC) is one of the most common malignancies. The main cause of death in HCC patients is tumor progression with invasion and metastasis. However, the underlying mechanisms of HCC invasion and metastasis are still not fully understood. Some studies show that the Notch signaling pathway may participate in tumor invasion and metastasis. However, the mechanisms by which the Notch signaling pathway mediates tumor cell invasion, especially in hepatocellular carcinoma, are not yet known. In the current study, we investigated the anti-invasion effect of the downregulation of the Notch signaling pathway by DAPT in HCC cells. The Notch signaling pathway inhibitor could suppress invasion of HCC cells via the extracellular signal-regulated kinases 1 and 2 (ERK1/2) signaling pathways, resulting in the downregulation of matrix metalloproteinase-2 and -9 (MMP-2 and -9) and vascular endothelial growth factor (VEGF). These observations suggested that inhibition of the Notch signaling pathway by DAPT would be useful for devising novel preventive and therapeutic strategies targeting invasion of HCC.

Inhibitory effects of microRNA-34a on cell migration and invasion of invasive urothelial bladder carcinoma by targeting Notch1

MicroRNAs (miRNAs or miRs) are a class of short, non-coding RNAs that participate in various oncological processes. This study aims to explore the roles of microRNA-34a (miR-34a) in invasive urothelial bladder carcinoma. miR-34a was transfected into bladder cancer cell lines 253J and J82. The miR-34a expression levels in tissues and cells were detected by using qRT-PCR. The Notch1 expression was detected by qRT-PCR and Western blotting. Cell migratory and invasive abilities were measured by Transwell chamber assay. Bioinformatics and luciferase assay were performed to predict and analyze the binding sites between miRNA-34a and Notch1. It was found that there was aberrant expression of miR-34a in bladder cancer tissues. Moreover, we revealed that ectopic expression of miR-34a suppressed cell migration and invasion, while forced expression of Notch1 increased cell migratory and invasive abilities. Finally, we observed that miR-34a transfection significantly down-regulated luciferase activity and reduced the mRNA and protein levels of Notch1. Our study concluded that microRNA-34a antagonizes Notch1 and inhibits cell migration and invasion of bladder cancer cells, which indicates the tumor-suppressive function of microRNA-34a in bladder cancer.

Lipoxins, resolvins, and protectins in the prevention and treatment of diabetic macular edema and retinopathy

Diabetic macular edema and retinopathy are low-grade inflammatory conditions. Infusions of antitumor necrosis factor-α (anti-TNF-α) antibody and antivascular endothelial growth factor (anti-VEGF) antibody have been shown to be at least partly effective in the treatment of diabetic macular edema and proliferative diabetic retinopathy. Intravitreal therapy of diabetic macular edema by the anti-TNF-α antibody has been found to produce significant side effects and anti-VEGF therapy to be ineffective. Nevertheless, these studies have indicated that the suppression of TNF-α and other proinflammatory cytokines and VEGF could be of benefit in diabetic macular edema and retinopathy. The retina is rich in polyunsaturated fatty acids, especially in ω-3, and several studies have shown that polyunsaturated fatty acids prevent diabetic retinopathy. Lipoxins, resolvins, and protectins derived from various polyunsaturated fatty acids possess anti-inflammatory actions and suppress the production of interleukin-6, and TNF-α and VEGF have antiangiogenic actions. In view of these evidences, I propose that lipoxins, resolvins, and protectins could be of significant benefit in the prevention and management of diabetic macular edema and retinopathy.

Wild-type amyloid beta 1-40 peptide induces vascular smooth muscle cell death independently from matrix metalloprotease activity

Cerebral amyloid angiopathy (CAA) is an important cause of intracerebral hemorrhages in the elderly, characterized by amyloid-β (Aβ) peptide accumulating in central nervous system blood vessels. Within the vessel walls, Aβ-peptide deposits [composed mainly of wild-type (WT) Aβ(1-40) peptide in sporadic forms] induce impaired adhesion of vascular smooth muscle cells (VSMCs) to the extracellular matrix (ECM) associated with their degeneration. This process often results in a loss of blood vessel wall integrity and ultimately translates into cerebral ischemia and microhemorrhages, both clinical features of CAA. In this study, we decipher the molecular mechanism of matrix metalloprotease (MMP)-2 activation in WT-Aβ(1-40) -treated VSMC and provide evidence that MMP activity, although playing a critical role in cell detachment disrupting ECM components, is not involved in the WT-Aβ(1-40) -induced degeneration of VSMCs. Indeed, whereas this peptide clearly induced VSMC apoptosis, neither preventing MMP-2 activity nor hampering the expression of membrane type1-MMP, or preventing tissue inhibitors of MMPs-2 (TIMP-2) recruitment (two proteins evidenced here as involved in MMP-2 activation), reduced the number of dead cells. Even the use of broad-range MMP inhibitors (GM6001 and Batimastat) did not affect WT-Aβ(1-40) -induced cell apoptosis. Our results, in contrast to those obtained using the Aβ(1-40) Dutch variant suggesting a link between MMP-2 activity, VSMC mortality and degradation of specific matrix components, indicate that the ontogenesis of the Dutch familial and sporadic forms of CAAs is different. ECM degradation and VSMC degeneration would be tightly connected in the Dutch familial form while being two independent processes in sporadic forms of CAA.

Transcriptome-based identification of antioxidative gene expression after fish oil supplementation in normo- and dyslipidemic men

Background

The beneficial effects of omega-3 polyunsaturated fatty acids (n-3 PUFAs), especially in dyslipidemic subjects with a high risk of cardiovascular disease, are widely described in the literature. A lot of effects of n-3 PUFAs and their oxidized metabolites are triggered by regulating the expression of genes. Currently, it is uncertain if the administration of n-3 PUFAs results in different expression changes of genes related to antioxidative mechanisms in normo- and dyslipidemic subjects, which may partly explain their cardioprotective effects. The aim of this study was to investigate the effects of n-3 PUFA supplementation on expression changes of genes involved in oxidative processes.

Methods

Ten normo- and ten dyslipidemic men were supplemented for twelve weeks with fish oil capsules, providing 1.14 g docosahexaenoic acid and 1.56 g eicosapentaenoic acid. Gene expression levels were determined by whole genome microarray analysis and quantitative real-time polymerase chain reaction (qRT-PCR).

Results

Using microarrays, we discovered an increased expression of antioxidative enzymes and a decreased expression of pro-oxidative and tissue enzymes, such as cytochrome P450 enzymes and matrix metalloproteinases, in both normo- and dyslipidemic men. An up-regulation of catalase and heme oxigenase 2 in both normo- and dyslipidemic subjects and an up-regulation of cytochrome P450 enzyme 1A2 only in dyslipidemic subjects could be observed by qRT-PCR analysis.

Conclusions

Supplementation of normo- and dyslipidemic subjects with n-3 PUFAs changed the expression of genes related to oxidative processes, which may suggest antioxidative and potential cardioprotective effects of n-3 PUFAs. Further studies combining genetic and metabolic endpoints are needed to verify the regulative effects of n-3 PUFAs in antioxidative gene expression to better understand their beneficial effects in health and disease prevention.

Trial registration

ClinicalTrials.gov (ID: NCT01089231)

The Notch pathway attenuates interleukin 1β (IL1β)-mediated induction of adenylyl cyclase 8 (AC8) expression during vascular smooth muscle cell (VSMC) trans-differentiation

Vascular smooth muscle cell (VSMC) trans-differentiation, or their switch from a contractile/quiescent to a secretory/inflammatory/migratory state, is known to play an important role in pathological vascular remodeling including atherosclerosis and postangioplasty restenosis. Several reports have established the Notch pathway as tightly regulating VSMC response to various stress factors through growth, migration, apoptosis, and de-differentiation. More recently, we showed that alterations of the Notch pathway also govern VSMC acquisition of the inflammatory state, one of the major events accelerating atherosclerosis. We also evidenced that the inflammatory context of atherosclerosis triggers a de novo expression of adenylyl cyclase isoform 8 (AC8), associated with the properties developed by trans-differentiated VSMCs. As an initial approach to understanding the regulation of AC8 expression, we examined the role of the Notch pathway. Here we show that inhibiting the Notch pathway enhances the effect of IL1β on AC8 expression, amplifies its deleterious effects on the VSMC trans-differentiated phenotype, and decreases Notch target genes Hrt1 and Hrt3. Conversely, Notch activation resulted in blocking AC8 expression and up-regulated Hrt1 and Hrt3 expression. Furthermore, overexpressing Hrt1 and Hrt3 significantly decreased IL1β-induced AC8 expression. In agreement with these in vitro findings, the in vivo rat carotid balloon-injury model of restenosis evidenced that AC8 de novo expression coincided with down-regulation of the Notch3 pathway. These results, demonstrating that the Notch pathway attenuates IL1β-mediated AC8 up-regulation in trans-differentiated VSMCs, suggest that AC8 expression, besides being induced by the proinflammatory cytokine IL1β, is also dependent on down-regulation of the Notch pathway occurring in an inflammatory context.

Molecular pathways of notch signaling in vascular smooth muscle cells

Notch signaling in the cardiovascular system is important during embryonic development, vascular repair of injury, and vascular pathology in humans. The vascular smooth muscle cell (VSMC) expresses multiple Notch receptors throughout its life cycle, and responds to Notch ligands as a regulatory mechanism of differentiation, recruitment to growing vessels, and maturation. The goal of this review is to provide an overview of the current understanding of the molecular basis for Notch regulation of VSMC phenotype. Further, we will explore Notch interaction with other signaling pathways important in VSMC.

Interleukin-1β modulates smooth muscle cell phenotype to a distinct inflammatory state relative to PDGF-DD via NF-κB-dependent mechanisms

Smooth muscle cell (SMC) phenotypic modulation in atherosclerosis and in response to PDGF in vitro involves repression of differentiation marker genes and increases in SMC proliferation, migration, and matrix synthesis. However, SMCs within atherosclerotic plaques can also express a number of proinflammatory genes, and in cultured SMCs the inflammatory cytokine IL-1β represses SMC marker gene expression and induces inflammatory gene expression. Studies herein tested the hypothesis that IL-1β modulates SMC phenotype to a distinct inflammatory state relative to PDGF-DD. Genome-wide gene expression analysis of IL-1β- or PDGF-DD-treated SMCs revealed that although both stimuli repressed SMC differentiation marker gene expression, IL-1β distinctly induced expression of proinflammatory genes, while PDGF-DD primarily induced genes involved in cell proliferation. Promoters of inflammatory genes distinctly induced by IL-1β exhibited over-representation of NF-κB binding sites, and NF-κB inhibition in SMCs reduced IL-1β-induced upregulation of proinflammatory genes as well as repression of SMC differentiation marker genes. Interestingly, PDGF-DD-induced SMC marker gene repression was not NF-κB dependent. Finally, immunofluorescent staining of mouse atherosclerotic lesions revealed the presence of cells positive for the marker of an IL-1β-stimulated inflammatory SMC, chemokine (C-C motif) ligand 20 (CCL20), but not the PDGF-DD-induced gene, regulator of G protein signaling 17 (RGS17). Results demonstrate that IL-1β- but not PDGF-DD-induced phenotypic modulation of SMC is characterized by NF-κB-dependent activation of proinflammatory genes, suggesting the existence of a distinct inflammatory SMC phenotype. In addition, studies provide evidence for the possible utility of CCL20 and RGS17 as markers of inflammatory and proliferative state SMCs within atherosclerotic plaques in vivo.

Matrix metalloproteinase-1 and -9 in human placenta during spontaneous vaginal delivery and caesarean sectioning in preterm pregnancy

Preterm birth is a major public health problem in terms of loss of life, long-term and short term disabilities worldwide. The process of parturition (both term and preterm) involves intensive remodelling of the extracellular matrix (ECM) in the placenta and fetal membranes by matrix metalloproteinases (MMPs). Our previous studies show reduced docosahexaenoic acid (DHA) in women delivering preterm. Further omega 3 fatty acids are reported to regulate MMP levels. This study was undertaken to examine the placental levels of MMPs and their association with placental DHA levels in women delivering preterm. The levels of MMP-1 and MMP-9 in 74 women delivering preterm (52 by spontaneous vaginal delivery and 22 by caesarean sectioning) and 75 women delivering at term (59 by spontaneous vaginal delivery and 16 by caesarean sectioning) were determined by enzyme-linked immunosorbent assay (ELISA) and their association with placental DHA was studied. Placental MMP-1 levels were higher (p<0.05) in women delivering preterm (both by spontaneous vaginal delivery and caesarean sectioning) as compared to those delivering at term. In contrast, placental MMP-9 levels in preterm pregnancies was higher (p<0.05) in women with spontaneous vaginal delivery while lower (p<0.05) in women delivering by caesarean sectioning. Low placental DHA was associated with higher placental MMP-9 levels. Our study suggests a differential effect of mode of delivery on the levels of MMPs from placenta. Further this study suggests a negative association of DHA and the levels of MMP-9 in human placenta although the mechanisms need further study.

Unmasking of LPA1 receptor-mediated migration response to lysophosphatidic acid by interleukin-1β-induced attenuation of Rho signaling pathways in rat astrocytes

Action mechanism of lipopolysaccharide (LPS), interleukin-1β (IL-1β), and lysophosphatidic acid (LPA) to regulate motility, an important process of astrogliosis, was investigated in rat astrocytes. While LPA exerted no significant effect on the cell migration, the prior treatment of the cells with LPS or IL-1β resulted in the appearance of migration activity in response to LPA. The LPS induction of the migration response to LPA was associated with the production of IL-1β precursor protein and inhibited by the IL-1 receptor antagonist. The IL-1β treatment also allowed LPA to activate Rac1. The LPA-induced Rac1 activation and migration were inhibited by pertussis toxin, a small interfering RNA specific to LPA(1) receptors, and LPA(1) receptor antagonists, including Ki16425. However, the IL-1β treatment had no appreciable effect on LPA(1) receptor mRNA expression and LPA-induced activation of ERK, Akt, and proliferation. The induction of the migration response to LPA by IL-1β was inhibited by a constitutively active RhoA. Moreover, LPA significantly activated RhoA through the LPA(1) receptor in the control cells but not in the IL-1β-treated cells. These results suggest that IL-1β inhibits the LPA(1) receptor-mediated Rho signaling through the IL-1 receptor, thereby disclosing the LPA(1) receptor-mediated G(i) protein/Rac/migration pathway.

Effects of long chain omega-3 fatty acids on metalloproteinases and their inhibitors in combined dyslipidemia patients

We evaluate the effect of a standardized dietary supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFAs) on the level of some markers of vascular remodeling in patients with combined dyslipidemia. Three hundred and thirty-three patients received placebo or n-3 PUFAs for 6 months. We evaluated body mass index, glycemic profile, blood pressure, lipid profile, lipoprotein(a), plasminogen activator inhibitor-1, homocysteine, fibrinogen, high-sensitivity C reactive protein, ADP, MMP-2 and MMP-9, and tissue inhibitors of metalloproteinase-1 and -2. A significant increase of high-density lipoprotein-cholesterol, and a significant decrease of triglycerides were present after 3 and 6 months with n-3 PUFAs intake. A significant plasminogen activator inhibitor-1, fibrinogen and high-sensitivity C reactive protein decrease was obtained after 3 and 6 months and a significant ADP increase was observed after 3 and 6 months of n-3 PUFAs. A significant MMP-2, MMP-9, tissue inhibitors of metalloproteinase-1 and tissue inhibitors of metalloproteinase-2 decrease was obtained after 6 months compared to the baseline value with n-3 PUFAs intake. n-3 PUFAs give a better lipid profile and a better improvement of coagulation, fibrinolytic and inflammatory parameters than placebo. Furthermore, lowers levels of MMP-2, MMP-9 and their tissue inhibitors are obtained with n-3 PUFAs compared to placebo.

Hydrogen peroxide enhances osteopontin expression and matrix metalloproteinase activity in aortic vascular smooth muscle cells

1. Restenosis after percutaneous coronary intervention (PCI) is a major clinical complication. However, the underlying mechanisms remain poorly understood. The present aim of the present study was to test the hypothesis that reactive oxygen species (ROS) enhance osteopontin (OPN) expression and increase matrix metalloproteinase (MMP)-2 activity (two major factors that contribute to restenosis) in aortic vascular smooth muscle cells (VSMC), thus facilitating restenosis. 2. Primary cultured rat aortic VSMC were exposed to different concentrations (10, 50 and 100 micromol/L) of H(2)O(2). The expression of OPN mRNA and protein was determined by reverse transcription-polymerase chain reaction and Western blotting, respectively. The activity of MMP-2 was determined by gelatin zymography. 3. The expression of OPN mRNA and protein in VSMC was enhanced by H(2)O(2) in a dose-dependent manner. In addition, H(2)O(2) at all concentrations tested (which are comparable to those seen in diabetic vascular tissues) significantly increased MMP-2 activity in VSMC. 4. Because vascular ROS production is significantly increased in patients with ischaemic disease and OPN and MMP-2 have been shown to play critical role in restenosis, the results of the present study strongly suggest that a ROS-initiated and OPN- and MMP-2-mediated signalling pathway may play an important role in accelerated restenosis after PCI in patients with ischaemic disease. Therefore, the H(2)O(2)-OPN/MMP-2 system may be a new therapeutic target in reducing restenosis in patients undergoing PCI.