Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 20

Atherosclerosis Related Abstracts

20 Endothelial Progenitor Cells Is a Determinant of Vascular Function and Atherosclerosis in Ankylosing Spondylitis

Authors: Ashit Syngle, Pawan Krishan, Inderjit Verma

Abstract:

Objective: Endothelial progenitor cells (EPCs) have reparative potential in overcoming the endothelial dysfunction and reducing cardiovascular risk. EPC depletion has been demonstrated in the setting of established atherosclerotic diseases. With this background, we evaluated whether reduced EPCs population are associated with endothelial dysfunction, subclinical atherosclerosis and inflammatory markers in ankylosing spondylitis (AS) patients without any known traditional cardiovascular risk factor in AS patients. Methods: Levels of circulating EPCs (CD34+/CD133+), brachial artery flow-mediated dilatation, carotid intima-media thickness (CIMT) and inflammatory markers i.e erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), tissue necrosis factor (TNF)–α, interleukin (IL)-6, IL-1 were assessed in 30 AS patients (mean age33.41 ± 10.25; 11 female and 19 male) who fulfilled the modified New York diagnostic criteria with 25 healthy volunteers (mean age 29.36± 8.64; 9 female and 16 male) matched for age and sex. Results: EPCs (CD34+/CD133+) cells were significantly (0.020 ± 0.001% versus 0.040 ± 0.010%, p<0.001) reduced in patients with AS compared to healthy controls. Endothelial function (7.35 ± 2.54 versus 10.27 ±1.73, p=0.002), CIMT (0.63 ± 0.01 versus 0.35 ± 0.02, p < 0.001) and inflammatory markers were also significantly (p < 0.01) altered as compared to healthy controls. Specifically, CD34+CD133+cells were inversely multivariate correlated with CRP and TNF-α and endothelial dysfunction was positively correlated with reduced number of EPC. Conclusion: Depletion of EPCs population is an independent predictor of endothelial dysfunction and early atherosclerosis in AS patients and may provide additional information beyond conventional risk factors and inflammatory markers.

Keywords: Cardiovascular, Atherosclerosis, ankylosing spondylitis, Endothelial Progenitor Cells

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19 The Palm Oil in Food Products: Frequency of Consumption and Composition

Authors: Abdelmajid Abid, Kamilia Ounaissa, Sarra Fennira, Asma Ben Brahim, Marwa Omri

Abstract:

The palm oil is the vegetable oil the most used by the food-processing industry in the world. It is chosen for its economic and technologic advantages. However, this oil arouses the debate because of its high content in saturated fatty acids, which are fats promoting atherosclerosis. Purposes of the work: To study the frequency and the rate of consumption of industrial products containing some palm oil and specify the rate of this oil in certain consummated products. Methodology: We proceeded to a consumer survey using a questionnaire collecting a list of food containing the palm oil, sold on the Tunisian market. We then analyzed the most consumed food to specify their fat content by “Soxhelt’s” method. Finally, we studied the composition in various fatty acids of the extracted fat using the chromatography in the gas phase (CPG) Results: Our results show that investigated individuals having a normal weight have a more important and more frequent consumption of products rich in palm oil than overweight subjects. The most consumed foods are biscuits, cakes, wafers, chocolates, chips, cereal, creams to be spread and canned pilchard. The content in palm oil of these products varies from 10 % to 31 %. The analysis by CPG showed an important content in saturated fatty acid, in particular in palmitic acid, ranging from 40 % to 63 % of the fat of these products. Conclusion: Our study shows a high frequency of consumption of food products, the analysis of which proved a high content in palm oil. Theses facts justifies the necessity of a regulation of the use of palm oil in food products and the application of a label detailing the type and fat rates used.

Keywords: Atherosclerosis, Food industry, Fatty Acids, palm oil, palmitic acid

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18 Oat βeta Glucan Attenuates the Development of Atherosclerosis and Improves the Intestinal Barrier Function by Reducing Bacterial Endotoxin Translocation in APOE-/- MICE

Authors: Dalal Alghawas, Jetty Lee, Kaisa Poutanen, Hani El-Nezami

Abstract:

Oat β-glucan a water soluble non starch linear polysaccharide has been approved as a cholesterol lowering agent by various food safety administrations and is commonly used to reduce the risk of heart disease. The molecular weight of oat β-glucan can vary depending on the extraction and fractionation methods. It is not clear whether the molecular weight has a significant impact at reducing the acceleration of atherosclerosis. The aim of this study was to investigate three different oat β-glucan fractionations on the development of atherosclerosis in vivo. With special focus on plaque stability and the intestinal barrier function. To test this, ApoE-/- female mice were fed a high fat diet supplemented with oat bran, high molecular weight (HMW) oat β-glucan fractionate and low molecular weight (LMW) oat β-glucan fractionate for 16 weeks. Atherosclerosis risk markers were measured in the plasma, heart and aortic tree. Plaque size was measured in the aortic root and aortic tree. ICAM-1, VCAM-1, E-Selectin, P-Selectin, protein levels were assessed from the aortic tree to determine plaque stability at 16 weeks. The expression of p22phox at the aortic root was evaluated to study the NADPH oxidase complex involved in nitric oxide bioavailability and vascular elasticity. The tight junction proteins E-cadherin and beta-catenin from western blot analyses were analysed as an intestinal barrier function test. Plasma LPS, intestinal D-lactate levels and hepatic FMO gene expression were carried out to confirm whether the compromised intestinal barrier lead to endotoxemia. The oat bran and HMW oat β-glucan diet groups were more effective than the LMW β-glucan diet group at reducing the plaque size and showed marked improvements in plaque stability. The intestinal barrier was compromised for all the experimental groups however the endotoxemia levels were higher in the LMW β-glucan diet group. The oat bran and HMW oat β-glucan diet groups were more effective at attenuating the development of atherosclerosis. Reasons for this could be due to the LMW oat β-glucan diet group’s low viscosity in the gut and the inability to block the reabsorption of cholesterol. Furthermore the low viscosity may allow more bacterial endotoxin translocation through the impaired intestinal barrier. In future food technologists should carefully consider how to incorporate LMW oat β-glucan as a health promoting food.

Keywords: Atherosclerosis, beta glucan, endotoxemia, intestinal barrier function

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17 Relation of Mean Platelet Volume with Serum Paraoxonase-1 Activity and Brachial Artery Diameter and Intima Media Thickness in Diabetic Patients with Respect to Obesity and Diabetic Complications

Authors: Pınar Karakaya, Meral Mert, Yildiz Okuturlar, Didem Acarer, Asuman Gedikbasi, Filiz Islim, Teslime Ayaz, Ozlem Soyluk, Ozlem Harmankaya, Abdulbaki Kumbasar

Abstract:

Objective: To evaluate the relation of mean platelet volume (MPV) levels with serum paraoxonase-1 activity and brachial artery diameter and intima media thickness in diabetic patients with respect to obesity and diabetic complications. Methods: A total of 201 diabetic patients grouped with respect to obesity [obese (n=89) and non-obese (n=112) and diabetic complications [with (n=50) or without (n=150) microvascular complications and with (n=91) or without (n=108) macrovascular complications] groups were included. Data on demographic and lifestyle characteristics of patients, anthropometric measurements, diabetes related microvascular and macrovascular complications, serum levels for MPV, bBrachial artery diameter and intima media thickness (IMT) and serum paraoxonase and arylesterase activities were recorded. Correlation of MPV values to paraoxonase and arylesterase activities as well as to brachial artery diameter and IMT was evaluated in study groups. Results: Mean(SD) paraoxonase and arylesterase values were 119.8(37.5) U/L and 149.0(39.9) U/L, respectively in the overall population with no significant difference with respect to obesity and macrovascular diabetic complications, whereas significantly lower values for paraoxonase (107.5(30.7) vs. 123.9(38.8) U/L, p=0.007) and arylesterase (132.1(30.2) vs. 154.7(41.2) U/L, p=0.001) were noted in patients with than without diabetic microvascular complications. Mean(SD) MPV values were 9.10 (0.87) fL in the overall population with no significant difference with respect to obesity and diabetic complications. No significant correlation of MPV values to paraoxonase, arylesterase activities, to brachial artery diameter and IMT was noted in the overall study population as well as in study groups. Conclusion: In conclusion, our findings revealed a significant decrease I PON-1 activity in diabetic patients with microvascular rather than macrovascular complications, whereas regardless of obesity and diabetic complications, no increase in thrombogenic activity and no relation of thrombogenic activity with PON-1 activity and brachial artery diameter and IMK.

Keywords: Obesity, Atherosclerosis, diabetes mellitus, microvascular complications, macrovascular complications, paraoxonase

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16 Anti-Phosphorylcholine T Cell Dependent Antibody

Authors: M. M. Rahman, A. Liu, A. Frostegard, J. Frostegard

Abstract:

The human immune system plays an essential role in cardiovascular disease (CVD) and atherosclerosis. Our earlier studies showed that major immunocompetent cells including T cells are activated by phosphorylcholine epitope. Further, we have determined for the first time in a clinical cohort that antibodies against phosphorylcholine (anti-PC) are negatively and independently associated with the development of atherosclerosis and thus a low risk of cardiovascular diseases. It is still unknown whether activated T cells play a role in anti-PC production. Here we aim to clarify the role of T cells in anti-PC production. B cell alone, or with CD3 T, CD4 T or with CD8 T cells were cultured in polystyrene plates to examine anti-PC IgM production. In addition to mixed B cell with CD3 T cell culture, B cells with CD3 T cells were also cultured in transwell co-culture plates. Further, B cells alone and mixed B cell with CD3 T cell cultures with or without anti-HLA 2 antibody were cultured for 6 days. Anti-PC IgM was detected by ELISA in independent experiments. More than 8 fold higher levels of anti-PC IgM were detected by ELISA in mixed B cell with CD3 T cell cultures in comparison to B cells alone. After the co-culture of B and CD3 T cells in transwell plates, there were no increased antibody levels indicating that B and T cells need to interact to augment anti-PC IgM production. Furthermore, anti-PC IgM was abolished by anti-HLA 2 blocking antibody in mixed B and CD3 T cells culture. In addition, the lack of increased anti-PC IgM in mixed B with CD8 T cells culture and the increased levels of anti-PC in mixed B with CD4 T cells culture support the role of helper T cell for the anti-PC IgM production. Atherosclerosis is a major cause of cardiovascular diseases, but anti-PC IgM is a protection marker for atherosclerosis development. Understanding the mechanism involved in the anti-PC IgM regulation could play an important role in strategies to raise anti-PC IgM. Studies suggest that anti-PC is T-cell independent antibody, but our study shows the major role of T cell in anti-PC IgM production. Activation of helper T cells by immunization could be a possible mechanism for raising anti-PC levels.

Keywords: Atherosclerosis, anti-PC, aardiovascular diseases, phosphorylcholine

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15 Assessing Arterial Blockages Using Animal Model and Computational Fluid Dynamics

Authors: Mohammad Al- Rawi, Ahmad Al- Jumaily

Abstract:

This paper investigates the effect of developing arterial blockage at the abdominal aorta on the blood pressure waveform at an externally accessible location suitable for invasive measurements such as the brachial and the femoral arteries. Arterial blockages are created surgically within the abdominal aorta of healthy Wistar rats to create narrowing resemblance conditions. Blood pressure waveforms are measured using a catheter inserted into the right femoral artery. Measurements are taken at the baseline healthy condition as well as at four different severities (20%, 50%, 80% and 100%) of arterial blockage. In vivo and in vitro measurements of the lumen diameter and wall thickness are taken using Magnetic Resonance Imaging (MRI) and microscopic techniques, respectively. These data are used to validate a 3D computational fluid dynamics model (CFD) which is developed to generalize the outcomes of this work and to determine the arterial stress and strain under the blockage conditions. This work indicates that an arterial blockage in excess of 20% of the lumen diameter significantly influences the pulse wave and reduces the systolic blood pressure at the right femoral artery. High wall shear stress and low circumferential strain are also generated at the blockage site.

Keywords: CFD, Atherosclerosis, pulse wave, arterial blockage

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14 Effects of Oxidized LDL in M2 Macrophages: Implications in Atherosclerosis

Authors: Fernanda Gonçalves, Karla Alcântara, Vanessa Moura, Patrícia Nolasco, Jorge Kalil, Maristela Hernandez

Abstract:

Introduction: Atherosclerosis is a chronic disease where two striking features are observed: retention of lipids and inflammation. Understanding the interaction between immune cells and lipoproteins involved in atherogenesis are urgent challenges, since cardiovascular diseases are the leading cause of death worldwide. Macrophages are critical to the development of atherosclerotic plaques and in the perpetuation of inflammation in these lesions. These cells are also directly involved in unstable plaque rupture. Recently different populations of macrophages are being identified in atherosclerotic lesions. Although the presence of M2 macrophages (macrophages activated by the alternative pathway, eg. The IL-4) has been identified, the function of these cells in atherosclerosis is not yet defined. M2 macrophages have a high endocytic capacity, they promote remodeling of tissues and to have anti-inflammatory activity. However, in atherosclerosis, especially unstable plaques, severe inflammatory reaction, accumulation of cellular debris and intense degradation of the tissue is observed. Thus, it is possible that the M2 macrophages have altered function (phenotype) in atherosclerosis. Objective: Our aim is to evaluate if the presence of oxidized LDL alters the phenotype and function of M2 macrophages in vitro. Methods: For this, we will evaluate whether the addition of lipoprotein in M2 macrophages differentiated in vitro with IL -4 induces 1) a reduction in the secretion of anti-inflammatory cytokines (CBA and ELISA), 2) secretion of inflammatory cytokines (CBA and ELISA), 3) expression of cell activation markers (Flow cytometry), 4) alteration in gene expression of molecules adhesion and extracellular matrix (Real-Time PCR) and 5) Matrix degradation (confocal microscopy). Results: In oxLDL stimulated M2 macrophages cultures we did not find any differences in the expression of the cell surface markers tested, including: HLA-DR, CD80, CD86, CD206, CD163 and CD36. Also, cultures stimulated with oxLDL had similar phagocytic capacity when compared to unstimulated cells. However, in the supernatant of these cultures an increase in the secretion of the pro-inflammatory cytokine IL-8 was detected. No significant changes where observed in IL-6, IL-10, IL-12 and IL-1b levels. The culture supernatant also induced massive extracellular matrix (produced by mouse embryo fibroblast) filaments degradation. When evaluating the expression of 84 extracellular matrix and adhesion molecules genes, we observed that the stimulation of oxLDL in M2 macrophages decreased 47% of the genes and increased the expression of only 3% of the genes. In particular we noted that oxLDL inhibit the expression of 60% of the genes constituents of extracellular matrix and collagen expressed by these cells, including fibronectin1 and collagen VI. We also observed a decrease in the expression of matrix protease inhibitors, such as TIMP 2. On the opposite, the matricellular protein thrombospondin had a 12 fold increase in gene expression. In the presence of native LDL 90% of the genes had no altered expression. Conclusion: M2 macrophages stimulated with oxLDL secrete the pro-inflammatory cytokine IL-8, have an altered extracellular matrix constituents gene expression, and promote the degradation of extracellular matrix. M2 macrophages may contribute to the perpetuation of inflammation in atherosclerosis and to plaque rupture.

Keywords: Atherosclerosis, macrophages, LDL

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13 Anti-TNF: Possibilities of Rising Anti-Phosphorylcholine Antibodies

Authors: Md. Mizanur Rahman, Anquan Liu, Anna Frostegård, Johan Frostegård

Abstract:

The role of the human immune system is essential in cardiovascular diseases and atherosclerosis. Activated cells in atherosclerosis produce abundant amounts of cytokines, but the exact mechanisms involved in the effects of these inflammatory cytokines are not clear in atherosclerosis. In a large clinical cohort, we have previously determined that antibodies against phosphorylcholine (anti-PC) are negatively and independently associated with both development of atherosclerosis and also a low risk of cardiovascular disease. Further, we reported that rheumatoid arthritis patients who were non-responders to TNF-inhibitors, where those with low anti-PC levels. Upon anti-TNF treatment, anti-PC levels increased. We, therefore, hypothesised that proinflammatory cytokines such as TNF could play a role in anti-PC regulation. Peripheral blood mononuclear cells (PBMC) were cultured with or without TNF and anti-TNF. The cell supernatants were collected after six days for ELISA measurements. In separate experiments, cells were cultured for 24 hours in both polystyrene plates and ELISPOT plates under a similar condition for ELISA and ELISPOT assays respectively. Total RNA was extracted after 6 hours of cell culture to perform RT-qPCR. Cell viability was confirmed by trypan blue staining and MTT assays. ELISA measurements detected less than 40% of anti-PC in TNF-treated cells, in comparison to control cells, whereas anti-PC production was recovered by anti-TNF treatment. ELISPOT assays showed that TNF suppresses anti-PC production by inhibiting anti-PC producing B-cells. In addition, RT-qPCR and ELISA showed that TNF also has effects also on B-cell activation as BAFF expression was inhibited by TNF treatment. Atherosclerosis is a major cause of cardiovascular diseases, but anti-PC is a protection marker for atherosclerosis development. Our findings show that TNF is a negative regulator of anti-PC production. Immune modulation and rising of anti-PC could be of major significance for the patients.

Keywords: Atherosclerosis, Cardiovascular Diseases, anti-PC, Anti-TNF, phosphorylecholine

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12 Inactivation of Semicarbazide-Sensitive Amine Oxidase Induces the Phenotypic Switch of Smooth Muscle Cells and Aggravates the Development of Atherosclerotic Lesions

Authors: Ying Zhao, Jun Wang, Miao Zhang, Limin Liu, Feng Zhi, Panpan Niu, Mengya Yang, Xuemei Zhu, Ying Diao

Abstract:

Background and Aims: Clinical studies have demonstrated that serum semicarbazide-sensitive amine oxidase (SSAO) activities positively correlate with the progression of atherosclerosis. The aim of the present study is to investigate the effect of SSAO inactivation on the development of atherosclerosis. Methods: Female LDLr knockout (KO) mice were given the Western-type diet for 6 and 9 weeks to induce the formation of early and advanced lesions, and semicarbazide (SCZ, 0.125%) was added into the drinking water to inactivate SSAO in vivo. Results: Despite no impact on plasma total cholesterol levels, abrogation of SSAO by SCZ not only resulted in the enlargement of both early (1.5-fold, p=0.0043) and advanced (1.8-fold, p=0.0013) atherosclerotic lesions, but also led to reduced/increased lesion contents of macrophages/smooth muscle cells (SMCs) (macrophage: ~0.74-fold, p=0.0002(early)/0.0016(advanced); SMC: ~1.55-fold, p=0.0003(early) /0.0001(advanced)), respectively. Moreover, SSAO inactivation inhibited the migration of circulating monocytes into peripheral tissues and reduced the amount of circulating Ly6Chigh monocytes (0.7-fold, p=0.0001), which may account for the reduced macrophage content in lesions. In contrast, the increased number of SMCs in lesions of SCZ-treated mice is attributed to an augmented synthetic vascular SMC phenotype switch as evidenced by the increased proliferation of SMCs and accumulation of collagens in vivo. Conclusion: SSAO inactivation by SCZ promotes the phenotypic switch of SMCs and the development of atherosclerosis. The enzymatic activity of SSAO may thus represent a potential target in the prevention and/or treatment of atherosclerosis.

Keywords: Atherosclerosis, phenotype switch of smooth muscle cells, SSAO/VAP-1, semicarbazide

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11 Total Plaque Area in Chronic Renal Failure

Authors: Hernán A. Perez, Luis J. Armando, Néstor H. García

Abstract:

Background and aims Cardiovascular disease rates are very high in patients with renal failure (CRF), but the underlying mechanisms are incompletely understood. Traditional cardiovascular risk factors do not explain the increased risk, and observational studies have observed paradoxical or absent associations between classical risk factors and mortality in dialysis patients. A large randomized controlled trial, the 4D Study, the AURORA and the ALERT study found that statin therapy in CRF do not reduce cardiovascular events. These results may be the results of ‘accelerated atherosclerosis’ observed on these patients. The objective of this study was to investigate if carotid total plaque area (TPA), a measure of carotid plaque burden growth is increased at progressively lower creatinine clearance in patients with CRF. We studied a cohort of patients with CRF not on dialysis, reasoning that risk factor associations might be more easily discerned before end stage renal disease. Methods: The Blossom DMO Argentina ethics committee approved the study and informed consent from each participant was obtained. We performed a cohort study in 412 patients with Stage 1, 2 and 3 CRF. Clinical and laboratory data were obtained. TPA was determined using bilateral carotid ultrasonography. Modification of Diet in Renal Disease estimation formula was used to determine renal function. ANOVA was used when appropriate. Results: Stage 1 CRF group (n= 16, 43±2yo) had a blood pressure of 123±2/78±2 mmHg, BMI 30±1, LDL col 145±10 mg/dl, HbA1c 5.8±0.4% and had the lowest TPA 25.8±6.9 mm2. Stage 2 CRF (n=231, 50±1 yo) had a blood pressure of 132±1/81±1 mmHg, LDL col 125±2 mg/dl, HbA1c 6±0.1% and TPA 48±10mm2 ( p< 0.05 vs CRF stage 1) while Stage 3 CRF (n=165, 59±1 yo) had a blood pressure of 134±1/81±1, LDL col 125±3 mg/dl, HbA1c 6±0.1% and TPA 71±6mm2 (p < 0.05 vs CRF stage 1 and 2). Conclusion: Our data indicate that TPA increases along the renal function deterioration, and it is not related with the LDL cholesterol and triglycerides levels. We suggest that mechanisms other than the classics are responsible for the observed excess of cardiovascular disease in CKD patients and finally, determination of total plaque area should be used to measure effects of antiatherosclerotic therapy.

Keywords: Atherosclerosis, Hypertension, cholesterol, chronic renal failure

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10 The Effect of Vitamin D Deficiency on Endothelial Function in Atherosclerosis Patients Living in Saudi Arabia

Authors: Wedad Azhar

Abstract:

Vitamin D is an essential fat-soluble vitamin that is required for the maintenance of good health. It is obtained either through exposure to sunlight (ultraviolet B radiation) or through dietary sources. The role of vitamin D is beyond bone health. Indeed, it plays a critical role in the immune system and a broad range of organ functions such as the cardiovascular system. Moreover, vitamin D plays a critical role in the endothelial function, which is one of the main indicators of atherosclerosis. This study is investigating the correlation between vitamin D status and endothelial function in preventing and treating atherosclerosis especially in country that has ample of sunshine but yet, Saudis from suffering from this issue vitamin D deficiency and insufficiency. Ninety participants from both genders and aged 40 to 60will be involved. The participants will be categorised into three groups: the control group will be healthy persons, patients at risk of developing atherosclerosis, patients formally diagnosed atherosclerosis. Half of the participants in each group should already have been taking vitamin D supplementations. Fasting blood samples will be taken from the participants for biochemical assays. Endothelial function will be assist by flow-mediated dilation of the brachial artery. Participants will be asked to complete a questionnaire on their social and economic status, education level, daily exposure to sunlight, smoking status, consumption of supplements and medication, and a food frequency of vitamin D intake. The data will be analysed using SPSS.

Keywords: Nutrition, Atherosclerosis, endothelial function, vitamin D

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9 The Potential of Acanthaster Plancii Fractions as Anti-Atherosclerotic Agent by Inhibiting the Expression of Proprotein Convertase Subtilisin-Kexin Type 9

Authors: Habsah Mohamad, Nurjannatul Naim Kamaruddin, Tengku Sifziuzl Tengku Muhammad, Aina Farahiyah Abdul Manan

Abstract:

Atherosclerosis which leads to cardiovascular diseases such as myocardial infarction, unstable angina (ischemic heart pain), sudden cardiac death and stroke is the principal cause of death worldwide. It has been a very critical issue as current common drug treatment, statin therapy has left bad side effects like rhabdomyolysis, atrial fibrillation, liver disease, abdominal and chest pain. Interestingly, the discoveries of proprotein convertase subtilisin-kexin type 9 have paved a new way in the treatment of atherosclerosis. This serine protease is believed to involve in the regulation of LDL- uptake by LDL-receptor. Therefore, this study was conducted to evaluate the potential of Acanthaster plancii fractions to reduce the transcriptional activity of the PCSK9 promoter. In this study, the marine organism which is Acanthaster plancii has been used as the source for marine compounds in inhibiting PCSK9. The cytotoxicity activity of ten fractions from the methanol extracts of Acanthaster plancii was investigated on HepG2 cell lines using MTS assay and dual glo luciferase assay was carried out later to analyses the effects of the samples in reducing the transcriptional activity of the PCSK9 promoter. Both assays used fractions with five different concentrations, 3.13µg/mL, 6.25µg/mL, 12.5µg/mL, 25µg/mL, and 50µg/mL. MTS assay indicated that the fractions are non-cytotoxic towards HepG2 cell lines as their IC50 value is greater than 30µg/mL. Whilst, for the dual glo luciferase assay, among all the fractions, Enhance Fraction 2 (EF2) showed the best potential in reducing the transcriptional activity of the PCSK9 promoter. The results indicated that this EF2 gave the lowest PCSK9 promoter expression at low concentration which is 0.2 fold change at 6.25µg/mL. This finding suggested that further analysis should be done to validate the potential of Acanthaster plancii as the source of anti-atherosclerotic agent.

Keywords: Atherosclerosis, Acanthaster plancii, luciferase assay, PCSK9

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8 Relationships of Plasma Lipids, Lipoproteins and Cardiovascular Outcomes with Climatic Variations: A Large 8-Year Period Brazilian Study

Authors: Vanessa H. S. Zago, Ana Maria H. de Avila, Paula P. Costa, Welington Corozolla, Liriam S. Teixeira, Eliana C. de Faria

Abstract:

Objectives: The outcome of cardiovascular disease is affected by environment and climate. This study evaluated the possible relationships between climatic and environmental changes and the occurrence of biological rhythms in serum lipids and lipoproteins in a large population sample in the city of Campinas, State of Sao Paulo, Brazil. In addition, it determined the temporal variations of death due to atherosclerotic events in Campinas during the time window examined. Methods: A large 8-year retrospective study was carried out to evaluate the lipid profiles of individuals attended at the University of Campinas (Unicamp). The study population comprised 27.543 individuals of both sexes and of all ages. Normolipidemic and dyslipidemic individuals classified according to Brazilian guidelines on dyslipidemias, participated in the study. For the same period, the temperature, relative humidity and daily brightness records were obtained from the Centro de Pesquisas Meteorologicas e Climaticas Aplicadas a Agricultura/Unicamp and frequencies of death due to atherosclerotic events in Campinas were acquired from the Brazilian official database DATASUS, according to the International Classification of Diseases. Statistical analyses were performed using both Cosinor and ARIMA temporal analysis methods. For cross-correlation analysis between climatic and lipid parameters, cross-correlation functions were used. Results: Preliminary results indicated that rhythmicity was significant for LDL-C and HDL-C in the cases of both normolipidemic and dyslipidemic subjects (n =respectively 11.892 and 15.651 both measures increasing in the winter and decreasing in the summer). On the other hand, for dyslipidemic subjects triglycerides increased in summer and decreased in winter, in contrast to normolipidemic ones, in which triglycerides did not show rhythmicity. The number of deaths due to atherosclerotic events showed significant rhythmicity, with maximum and minimum frequencies in winter and summer, respectively. Cross-correlation analyzes showed that low humidity and temperature, higher thermal amplitude and dark cycles are associated with increased levels of LDL-C and HDL-C during winter. In contrast, TG showed moderate cross-correlations with temperature and minimum humidity in an inverse way: maximum temperature and humidity increased TG during the summer. Conclusions: This study showed a coincident rhythmicity between low temperatures and high concentrations of LDL-C and HDL-C and the number of deaths due to atherosclerotic cardiovascular events in individuals from the city of Campinas. The opposite behavior of cholesterol and TG suggest different physiological mechanisms in their metabolic modulation by climate parameters change. Thus, new analyses are underway to better elucidate these mechanisms, as well as variations in lipid concentrations in relation to climatic variations and their associations with atherosclerotic disease and death outcomes in Campinas.

Keywords: Atherosclerosis, climatic variations, lipids and lipoproteins, associations

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7 Analysis of Adipose Tissue-Derived Mesenchymal Stem Cells under Atherosclerosis Microenvironment

Authors: Do Khanh Vy, Vuong Cat Khanh, Osamu Ohneda

Abstract:

During atherosclerosis (AS) progression, perivascular adipose tissue-derived mesenchymal stem cells (PVAT-MSCs) are exposed to the hypoxic environment due to the oxygenic deprivation which might influence the adipose tissue-derived mesenchymal stem cells (AT-MSCs) function. Additionally, it has been reported that the angiogenic ability of subcutaneous AT-MSCs (SAT-MSCs) was impaired in the AS patients. However, up to now, the effects of AS on the characteristics and function of PVAT-MSCs have not been clarified yet. In the present study, we analyzed the AS microenvironment effects on the characteristics and function of AT-MSCs. We found that there was no significant difference in cellular morphology and differentiation ability between SAT-MSCs and PVAT-MSCs in AS patients. However, the proliferation of AS-derived PVAT-MSCs was less than those of AS-derived SAT-MSCs. Importantly, the migration of AS-derived PVAT-MSCs was faster than AS-derived SAT-MSCs. Of note, AS-derived PVAT-MSCs showed the upregulation of SDF1, which is related to the homing, and VEGF, which is related to the angiogenesis compared to those of AS-derived SAT-MSCs. Consistent with these results, AS-derived PVAT-MSCs showed the higher ability to recruit EPCs and ECs than AS-derived SAT-MSCs. In addition, EPCs and ECs which cultured in the presence of AS-derived PVAT-MSC conditioned medium showed the higher angiogenic function of the tube formation compared to those cultured in AS-derived SAT-MSC conditioned medium. This result suggests that the higher paracrine effects of AS-derived PVAT-MSCs support the angiogenic function of the target cells. Our data showed the different characteristics and functions of AT-MSCs derived from different sources of tissues. Under the AS microenvironment, it seems that the characteristics and functions of PVAT-MSCs might reflect the progression of AS. Further study will be necessary to clarify the mechanism in the future.

Keywords: Atherosclerosis, mesenchymal stem cells, perivascular adipose tissue, subcutaneous adipose tissue

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6 Shear Stress and Effective Structural Stress ‎Fields of an Atherosclerotic Coronary Artery

Authors: Alireza Gholipour, Mergen H. Ghayesh, Anthony Zander, Stephen J. Nicholls, Peter J. Psaltis

Abstract:

A three-dimensional numerical model of an atherosclerotic coronary ‎artery is developed for the determination of high-risk situation and ‎hence heart attack prediction. Employing the finite element method ‎‎(FEM) using ANSYS, fluid-structure interaction (FSI) model of the ‎artery is constructed to determine the shear stress distribution as well ‎as the von Mises stress field. A flexible model for an atherosclerotic ‎coronary artery conveying pulsatile blood is developed incorporating ‎three-dimensionality, artery’s tapered shape via a linear function for ‎artery wall distribution, motion of the artery, blood viscosity via the ‎non-Newtonian flow theory, blood pulsation via use of one-period ‎heartbeat, hyperelasticity via the Mooney-Rivlin model, viscoelasticity ‎via the Prony series shear relaxation scheme, and micro-calcification ‎inside the plaque. The material properties used to relate the stress field ‎to the strain field have been extracted from clinical data from previous ‎in-vitro studies. The determined stress fields has potential to be used as ‎a predictive tool for plaque rupture and dissection.‎ The results show that stress concentration due to micro-calcification ‎increases the von Mises stress significantly; chance of developing a ‎crack inside the plaque increases. Moreover, the blood pulsation varies ‎the stress distribution substantially for some cases.‎

Keywords: Atherosclerosis, Fluid-Structure Interaction, pulsatile flow, coronary arteries‎

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5 Understanding the Role of Nitric Oxide Synthase 1 in Low-Density Lipoprotein Uptake by Macrophages and Implication in Atherosclerosis Progression

Authors: Anjali Roy, Mirza S. Baig

Abstract:

Atherosclerosis is a chronic inflammatory disease characterized by the formation of lipid rich plaque enriched with necrotic core, modified lipid accumulation, smooth muscle cells, endothelial cells, leucocytes and macrophages. Macrophage foam cells play a critical role in the occurrence and development of inflammatory atherosclerotic plaque. Foam cells are the fat-laden macrophages in the initial stage atherosclerotic lesion formation. Foam cells are an indication of plaque build-up, or atherosclerosis, which is commonly associated with increased risk of heart attack and stroke as a result of arterial narrowing and hardening. The mechanisms that drive atherosclerotic plaque progression remain largely unknown. Dissecting the molecular mechanism involved in process of macrophage foam cell formation will help to develop therapeutic interventions for atherosclerosis. To investigate the mechanism, we studied the role of nitric oxide synthase 1(NOS1)-mediated nitric oxide (NO) on low-density lipoprotein (LDL) uptake by bone marrow derived macrophages (BMDM). Using confocal microscopy, we found that incubation of macrophages with NOS1 inhibitor, TRIM (1-(2-Trifluoromethylphenyl) imidazole) or L-NAME (N omega-nitro-L-arginine methyl ester) prior to LDL treatment significantly reduces the LDL uptake by BMDM. Further, addition of NO donor (DEA NONOate) in NOS1 inhibitor treated macrophages recovers the LDL uptake. Our data strongly suggest that NOS1 derived NO regulates LDL uptake by macrophages and foam cell formation. Moreover, we also checked proinflammatory cytokine mRNA expression through real time PCR in BMDM treated with LDL and copper oxidized LDL (OxLDL) in presences and absences of inhibitor. Normal LDL does not evoke cytokine expression whereas OxLDL induced proinflammatory cytokine expression which significantly reduced in presences of NOS1 inhibitor. Rapid NOS-1-derived NO and its stable derivative formation act as signaling agents for inducible NOS-2 expression in endothelial cells, leading to endothelial vascular wall lining disruption and dysfunctioning. This study highlights the role of NOS1 as critical players of foam cell formation and would reveal much about the key molecular proteins involved in atherosclerosis. Thus, targeting NOS1 would be a useful strategy in reducing LDL uptake by macrophages at early stage of disease and hence dampening the atherosclerosis progression.

Keywords: Atherosclerosis, Inflammation, NOS1, oxidized LDL

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4 Prednisone and Its Active Metabolite Prednisolone Attenuate Lipid Accumulation in Macrophages

Authors: H. Jeries, N. Volkova, C. G. Iglesias, M. Najjar, M. Rosenblat, M. Aviram, T. Hayek

Abstract:

Background: Synthetic forms of glucocorticoids (e.g., prednisone, prednisolone) are anti-inflammatory drugs which are widely used in clinical practice. The role of glucocorticoids (GCs) in cardiovascular diseases including atherosclerosis is highly controversial, and their impact on macrophage foam cell formation is still unknown. Our aim was to investigate the effects of prednisone or its active metabolite, prednisolone, on macrophage oxidative stress and lipid metabolism using in-vivo, ex-vivo and in-vitro systems. Methods: The in-vivo study included C57BL/6 mice which were intraperitoneally injected with prednisone or prednisolone (5mg/kg) for 4 weeks, followed by lipid metabolism analyses in the mice aorta, and in peritoneal macrophages (MPM). In the ex-vivo study, we analyzed the effect of serum samples obtained from 9 healthy volunteers before or after treatment with oral prednisone (20mg for 5 days), on J774A.1 macrophage atherogenicity. In-vitro studies were conducted using J774A.1 macrophages, human monocyte derived macrophages (HMDM) and fibroblasts. Cells were incubated with increasing concentrations (0-200 ng/ml) of prednisone or prednisolone, followed by determination of cellular oxidative status, triglyceride and cholesterol metabolism. Results: Prednisone or prednisolone treatment resulted in a significant reduction in triglycerides and mainly in cholesterol cellular accumulation in MPM or in J774A.1 macrophages incubated with human serum. Similar resulted were noted in HMDM or in J774A.1 macrophages which were directly incubated with the GCs. These effects were associated with GCs inhibitory effect on triglycerides and cholesterol biosynthesis rates, throughout downregulation of diacylglycerol acyltransferase1 (DGAT1) expression, and of the sterol regulatory element binding protein (SREBP2) and HMGCR expression, respectively. In parallel to prednisone or prednisolone induced reduction in macrophage triglyceride content, paraoxonase 2 (PON2) expression was significantly upregulated. GCs-induced reduction of cellular triglyceride and cholesterol mass was mediated by the GCs receptors on macrophages since the GCs receptor antagonist (RU 486) abolished these effects. In fibroblasts, unlike macrophages, prednisone or prednisolone showed no anti-atherogenic effects. Conclusions: Prednisone or prednisolone are anti-atherogenic since they protected macrophages from lipid accumulation and foam cell formation.

Keywords: Atherosclerosis, macrophage, cholesterol, triglycerides, prednisolone, prednisone, foam cell

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3 CFD Analysis of the Blood Flow in Left Coronary Bifurcation with Variable Angulation

Authors: Midiya Khademi, Ali Nikoo, Shabnam Rahimnezhad Baghche Jooghi

Abstract:

Cardiovascular diseases (CVDs) are the main cause of death globally. Most CVDs can be prevented by avoiding habitual risk factors. Separate from the habitual risk factors, there are some inherent factors in each individual that can increase the risk potential of CVDs. Vessel shapes and geometry are influential factors, having great impact on the blood flow and the hemodynamic behavior of the vessels. In the present study, the influence of bifurcation angle on blood flow characteristics is studied. In order to approach this topic, by simplifying the details of the bifurcation, three models with angles 30°, 45°, and 60° were created, then by using CFD analysis, the response of these models for stable flow and pulsatile flow was studied. In the conducted simulation in order to eliminate the influence of other geometrical factors, only the angle of the bifurcation was changed and other parameters remained constant during the research. Simulations are conducted under dynamic and stable condition. In the stable flow simulation, a steady velocity of 0.17 m/s at the inlet plug was maintained and in dynamic simulations, a typical LAD flow waveform is implemented. The results show that the bifurcation angle has an influence on the maximum speed of the flow. In the stable flow condition, increasing the angle lead to decrease the maximum flow velocity. In the dynamic flow simulations, increasing the bifurcation angle lead to an increase in the maximum velocity. Since blood flow has pulsatile characteristics, using a uniform velocity during the simulations can lead to a discrepancy between the actual results and the calculated results.

Keywords: CFD, Atherosclerosis, Cardiovascular Disease, bifurcation, coronary artery, artery wall shear stress

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2 Mathematical Modelling of Blood Flow with Magnetic Nanoparticles as Carrier for Targeted Drug Delivery in a Stenosed Artery

Authors: Sreeparna Majee, G. C. Shit

Abstract:

A study on targeted drug delivery is carried out in an unsteady flow of blood infused with magnetic NPs (nanoparticles) with an aim to understand the flow pattern and nanoparticle aggregation in a diseased arterial segment having stenosis. The magnetic NPs are supervised by the magnetic field which is significant for therapeutic treatment of arterial diseases, tumor and cancer cells and removing blood clots. Coupled thermal energy have also been analyzed by considering dissipation of energy because of the application of the magnetic field and the viscosity of blood. Simulation technique used to solve the mathematical model is vorticity-stream function formulations in the diseased artery. An elevation in SLP (Specific loss power) is noted in the aortic bloodstream when the agglomeration of nanoparticles is higher. This phenomenon has potential application in the treatment of hyperthermia. The study focuses on the lowering of WSS (Wall Shear Stress) with increasing particle concentration at the downstream of the stenosis which depicts the vigorous flow circulation zone. These low shear stress regions prolong the residing time of the nanoparticles carrying drugs which soaks up the LDL (Low Density Lipoprotein) deposition. Moreover, an increase in NP concentration enhances the Nusselt number which marks the increase of heat transfer from the arterial wall to the surrounding tissues to destroy tumor and cancer cells without affecting the healthy cells. The results have a significant influence in the study of medicine, to treat arterial diseases such as atherosclerosis without the need for surgery which can minimize the expenditures on cardiovascular treatments.

Keywords: Atherosclerosis, magnetic nanoparticles, hyperthermia, blood flow

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1 Inflammatory Markers in the Blood and Chronic Periodontitis

Authors: Saimir Heta, Nevila Alliu, Tea Meta, Ilma Robo

Abstract:

Background: Plasma levels of inflammatory markers are the expression of the infectious wastes of existing periodontitis, as well as of existing inflammation everywhere in the body.Materials and Methods: The study consists of the clinical part of the measurement of inflammatory markers of 23 patients diagnosed with chronic periodontitis and the recording of parental periodontal parameters of patient periodontal status: hemorrhage index and probe values, before and 7-10 days after non-surgical periodontal treatment. Results: The level of fibrinogen drops according to the categorization of disease progression, active and passive, with the biggest % (18%-30%) at the fluctuation 10-20 mg/d. Fluctuations in fibrinogen level according to the age of patients in the range 0-10 mg / dL under 40 years and over 40 years was 13% -26%, in the range 10-20 mg / dL was 26% -22%, in the 20- mg / dL was 9% -4%. Conclusions: Non-surgical periodontal treatment significantly reduces the level of non-inflammatory markers in the blood. Oral health significantly reduces the potential source for periodontal bacteria, with the potential of promoting thromboembolism, through interaction between thrombocytes.

Keywords: Atherosclerosis, risk factor, inflammatory markers, chronic periodontitis

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