Collagen peptides affect collagen synthesis and the expression of collagen, elastin, and versican genes in cultured human dermal fibroblasts.

Background: Collagen is one of the major proteins of the skin and it is particularly important for its strength and resilience. Skin aging is a natural process that is characterized by the decrease and fragmentation of collagen in the dermis. Oral supplementation with collagen peptides has been clinically shown to have a positive effect on the skin condition. However, the mechanisms of aging-related changes synthesized by cells exposed to collagen are currently not well understood. Therefore, in this in vitro study, the mechanisms associated with collagen, elastin, and versican in human dermal fibroblasts were investigated after exposure to collagen peptides. Methods: The effects of different concentrations of collagen peptides on cell viability and metabolism were analyzed. For gene expression analysis, human dermal fibroblasts were treated with collagen peptides. This was then followed by RNA extraction and DNA synthesis. Gene expressions of collagen type 1 (COL1A1), elastin (ELN), and versican (VCAN) were quantified by quantitative reverse transcription polymerase chain reaction (RT-qPCR). In addition, collagen levels were analyzed by confocal scanning laser microscopy using immunostaining. Results: Collagen peptides tested in the study increased the expression of the relevant COL1A1, ELN, and VCAN genes in human dermal fibroblasts (p < 0.005). Furthermore, confocal microscopy showed increased collagen expression in the dermal fibroblast culture after treatment with the collagen peptides (p < 0.005). Conclusion: These data provide cell-based evidence for the beneficial effects of exposure to collagen peptides on the skin's collagen content and on the molecules that provide firmness and elasticity. This may support the hypothesis that collagen peptides are important for maintaining extracellular matrix (ECM) structure and skin regeneration.

Modelling health and economic impact of nutrition interventions: a systematic review.

Diet related non-communicable diseases (NCDs), as well as micronutrient deficiencies, are of widespread and growing importance to public health. Authorities are developing programs to improve nutrient intakes via foods. To estimate the potential health and economic impact of these programs there is a wide variety of models. The aim of this review is to evaluate existing models to estimate the health and/or economic impact of nutrition interventions with a focus on reducing salt and sugar intake and increasing vitamin D, iron, and folate/folic acid intake. The protocol of this systematic review has been registered with the International Prospective Register of Systematic Reviews (PROSPERO: CRD42016050873). The final search was conducted on PubMed and Scopus electronic databases and search strings were developed for salt/sodium, sugar, vitamin D, iron, and folic acid intake. Predefined criteria related to scientific quality, applicability, and funding/interest were used to evaluate the publications. In total 122 publications were included for a critical appraisal: 45 for salt/sodium, 61 for sugar, 4 for vitamin D, 9 for folic acid, and 3 for iron. The complexity of modelling the health and economic impact of nutrition interventions is dependent on the purpose and data availability. Although most of the models have the potential to provide projections of future impact, the methodological challenges are considerable. There is a substantial need for more guidance and standardization for future modelling, to compare results of different studies and draw conclusions about the health and economic impact of nutrition interventions.

Cross-Sectional Evaluation of Food Items Preferred by Adolescents under the Influence of Television Advertisements.

BACKGROUND: Food and beverage advertisements on television play a significant role in food preferences, especially among children and adolescents. This study aimed to evaluate foods and beverages advertised on television and purchased by adolescents or their families using the World Health Organization (WHO) nutrient profiling model. STUDY DESIGN: A cross-sectional study. METHODS: This cross-sectional study was performed on 2,699 students (1380 males and 1319 females) aged 11-16 in Ankara, Turkey, in 2015. Socio-demographic characteristics, television-viewing habits, and the tendency to purchase foods and beverages under the influence of TV advertisements were recorded. The body weight and height were measured by the researchers. All reported food and beverage items (n  =  284) were evaluated and classified as permitted or not permitted to advertise, according to the WHO nutrient profile model (2015). RESULTS: The majority (69.8%) of students were underweight/normal weight, whereas 13.3% and 16.9% were classified as overweight and obese, respectively. A total of 69.6% of adolescents declared that they were influenced by food advertisements, and 66.4% bought those foods. The most purchased products included cakes and sweet biscuits (63.8%), chocolate and confectionery (44.9%), savory snacks (39.6%), and soft drinks (25.4%). Only 8.5% of all the advertised products (n  =  284) were permitted to be advertised, according to the WHO nutrient profile model (2015). Dairy products, meat products, grains, fruits and vegetables, soup, and some traditional Turkish foods (e.g., cig kofte and Turkish pizza) were permitted. The permitted products were preferred by only 13.6% of the adolescents. CONCLUSIONS: Unhealthy foods are advertised on television for adolescents, and food advertisement management may be an essential strategy to provide healthy food choices.

Dietary fatty acids and CD36-mediated cholesterol homeostasis: potential mechanisms.

Currently, the prevention and treatment of CVD have been a global focus since CVD is the number one cause of mortality and morbidity. In the pathogenesis of CVD, it was generally thought that impaired cholesterol homeostasis might be a risk factor. Cholesterol homeostasis is affected by exogenous factors (i.e. diet) and endogenous factors (i.e. certain receptors, enzymes and transcription factors). In this context, the number of studies investigating the potential mechanisms of dietary fatty acids on cholesterol homeostasis have increased in recent years. As well, the cluster of differentiation 36 (CD36) receptor is a multifunctional membrane receptor involved in fatty acid uptake, lipid metabolism, atherothrombosis and inflammation. CD36 is proposed to be a crucial molecule for cholesterol homeostasis in various mechanisms including absorption/reabsorption, synthesis, and transport of cholesterol and bile acids. Moreover, it has been reported that the amount of fatty acids and fatty acid pattern of the diet influence the CD36 level and CD36-mediated cholesterol metabolism principally in the liver, intestine and macrophages. In these processes, CD36-mediated cholesterol and lipoprotein homeostasis might be impaired by dietary SFA and trans-fatty acids, whereas ameliorated by MUFA in the diet. The effects of PUFA on CD36-mediated cholesterol homeostasis are controversial depending on the amount of n-3 PUFA and n-6 PUFA, and the n-3:n-6 PUFA ratio. Thus, since the CD36 receptor is suggested to be a novel nutrient-sensitive biomarker, the role of CD36 and dietary fatty acids in cholesterol metabolism might be considered in medical nutrition therapy in the near future. Therefore, the novel nutritional target of CD36 and interventions that focus on dietary fatty acids and potential mechanisms underlying cholesterol homeostasis are discussed in this review.

Hepatic cholesterol synthesis and lipoprotein levels impaired by dietary fructose and saturated fatty acids in mice: Insight on PCSK9 and CD36.

OBJECTIVES: The aim of this study was to investigate the uncertain effects of high saturated fatty acids (SFAs) or fructose intake on cholesterol and lipoproteins with an insight of proprotein convertase subtilisin/kexin type 9 (PCSK9)- and cluster of differentiation 36 (CD36)-induced mechanisms. METHODS: Forty male C57 BL/6 mice (8 wks of age) were divided into four groups and fed ad libitum with standard chow or three isocaloric diets containing high SFAs (SFA group), monounsaturated fatty acids (MUFA group, vehicle), or fructose for 15 wks. Subsequently, mice were sacrificed and blood, liver, and heart were collected for further analysis. RESULTS: Consequently, fructose or SFA intake resulted in higher plasma and liver total cholesterol (TC) levels, plasma low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (HDL-C), apolipoprotein (Apo)-B levels, TC/HDL-C, and LDL-C/HDL-C ratios, and lower plasma levels of HDL-C and Apo-A1 (P < 0.05). Levels of 3-hydroxy-3-methylglutaryl-CoA reductase and acetyl-CoA acetyltransferase 1 enzymes in liver and CD36 levels in plasma were elevated by high SFAs and fructose intake (P < 0.05), whereas plasma PCSK9 levels were not significantly changed. Fructose and SFA intake increased PCSK9 and CD36 levels in the heart, along with increased CD36 levels in the liver (P < 0.05). Furthermore, plasma LDL-C was found to be positively correlated with liver PCSK9 (r = 0.85, P = 0.02), and CD36 (r = 0.70, P = 0.02) in the SFA and fructose groups. CONCLUSION: High intakes of dietary SFAs and fructose might induce dysregulations in the cholesterol synthesis and blood lipoprotein levels via proposed nutrient-sensitive biomarkers PCSK9 and CD36 in liver and extrahepatic tissues involved in cholesterol homeostasis.

Potential effect of maternal dietary sucrose or fructose syrup on CD36, leptin, and ghrelin-mediated fetal programming of obesity.

The influence of HFCS (high fructose corn syrup - free fructose) and sucrose (bound fructose) on fetal appetite signals is unknown. This study aimed to determine the effects of HFCS or sucrose on the peptide-mediated appetite regulation in fetal programming of obesity. Sprague Dawley female rats were administered feed and plain water (control) or water containing maltodextrin (vehicle), sucrose, fructose, or HFCS (20%, w/v) for 12 weeks before mating and throughout pregnancy and lactation (ndams = 31; npups = 207). Maternal chow-feed consumption in the HFCS and sucrose groups and sugar-added drink consumption in the HFCS group were higher compared to the vehicle and control groups (P < 0.05). The total body fat accumulated in sucrose, fructose, and HFCS groups in dams and pups was higher than those in the vehicle and control groups (P < 0.05). The HFCS groups showed lower plasma leptin levels and higher ghrelin levels. Soluble CD36 levels in plasma and tongue samples were high in HFCS groups of dams and pups (P < 0.05). Rather than bound fructose, the free fructose from the maternal diet contributes to the programming of obesity through the disruption of leptin, ghrelin, and CD36 expression involved in appetite regulation.

The potential efficacy of dietary fatty acids and fructose induced inflammation and oxidative stress on the insulin signaling and fat accumulation in mice.

The aim of the present study was to clarify whether oxidative stress and inflammatory responses are related to impaired insulin signaling and fat accumulation induced by the dietary fatty acids and fructose. C57BL/6 type 8 week-old male mice (n = 10/per group) were fed with standard chow or three isocaloric diets consisting fructose, monounsaturated fatty acids (MUFA), or saturated fatty acid (SFA) for 15 weeks. After the dietary manipulation, the mice were sacrificed, tissues and blood were collected. Consequently, body weight gains, liver weights, and plasma homeostasis model of assessment-insulin resistance (HOMA-IR) values in were at higher levels in SFA and fructose groups (p < 0.05). The plasma concentrations of the non-esterified fatty acids (NEFA), triglyceride (TG), and liver steatosis were found to be at higher levels in SFA and fructose groups (p < 0.05). Moreover, the expression levels of acetyl-CoA carboxylase-1 (ACC1), insulin receptor substrate-1 (IRS1), AMP-activated protein kinase (AMPK), and toll-like receptor-4 (TLR4) in the liver were affected by the intake of SFA and fructose. Furthermore, the plasma levels of C-reactive protein (CRP) and monocyte chemoattractant protein-1 (MCP1) and the thiobarbituric acid reactive substances (TBARS) in the liver were elevated in SFA and fructose group (p < 0.05). The plasma level of anti-inflammatory cytokine interleukin-10 (IL -10) was found to be lower in the SFA group compared to the other groups (p < 0.05). In conclusion, the inflammation and oxidation are related with the fatty acid- and fructose-induced impaired insulin signaling and fat accumulation in liver. Hence, in order to decrease the oxidative stress and pro-inflammatory response, it is substantial to reduce the saturated fat and added sugar or to replace with the unsaturated fat and complex carbohydrates in diet.

Turkish version of the Yale Food Addiction Scale: preliminary results of factorial structure, reliability, and construct validity.

BACKGROUND: Yale Food Addiction Scale (YFAS) was established to identify individuals exhibiting signs of addiction towards certain types of food. This study aimed to develop a Turkish version of the Yale Food Addiction Scale and test its psychometric properties. METHODS: The backward translation techniques were used to develop Turkish versions of the YFAS, and its reproducibility was assessed. Turkish version of the YFAS was administered to a total of 1033 participants (439 men and 594 women), aged 19-65 years. Exploratory factor analysis and confirmatory factor analysis were used to examine the factorial structure of the tool. Construct validity was assessed by principal component factor analysis with varimax rotation. Reliabilities were estimated with Cronbach's alpha coefficient. The criterion-related validity was tested by the administration of Eating Attitude Test-26 (EAT-26) to all participants. RESULTS: The primary factor loadings for seven items were ranged between 0.45 and 0.79, and no items cross-loaded onto other factors. The fit indices showed that eight items of the YFAS were a good representation of the item responses and each item loaded significantly on the specified factor (p < 0.001 for each). YFAS subscales had a high internal consistency and test-retest reliability. The criterion-related validity of the tool showed a positive relationship with scales of the EAT-26. CONCLUSION: Current study suggested that the Turkish version of the YFAS is a reliable, valid, and useful tool for assessing the signs of food addiction in a non-clinical sample.

[Is There an Effect of Dietary Fructose on Development and Prognosis of Chronic Diseases?] / Diyetle Alinan Fruktozun Kronik Hastaliklarin Gelismesinde ve Prognozunda Etkisi Var midir?

Dietary sources of fructose are not only honey, fruit, sucrose, but also high fructose corn syrup in various foods and beverages. Total amount of daily fructose intake is rising by especially increasing use of high fructose corn syrup in the food industry. Fructose can lead to obesity by contributing to high-energy intake and lipogenesis in the body. Depending on the source of fructose, dose and duration, it was involved in de-novo lipid synthesis. Fructose may increase the risk of insulin resistance, non-alcoholic fatty liver and kidney diseases by affecting blood glucose and insulin levels. On the other hand, fructose may initiate inflammatory processes in the organism. In addition to these, fat or salt consisting typical western type diet with high fructose consumption, can increase the potential effect of fructose on chronic diseases. As a result, although it is not fully supported by clinical studies, it is thought that high amounts of fructose intake may increase the risk of chronic disease shown by experimental studies. Also it should be noted that beside high fructose, typical western-style high-fat and high-salt diet may increase the risk of chronic diseases such as obesity, cardiovascular diseases and worsen metabolic syndrome parameters. Furthermore, synthetic fructose, is able to cause some adverse metabolic effects when taken in large amounts; consumption of high amounts of fructose by fruit or honey these negative effects can be either not seen or less observed based on the amount.

How does food addiction influence dietary intake profile?

This study aimed to investigate whether there was any difference in eating pattern, abnormal eating behaviour, obesity and the number of food addiction symptoms according to food addiction presence. A total sample of 851 healthy subjects living in Ankara (n = 360 male, n = 491 female) aged 19-65 years were included in this cross-sectional survey. Data on demographic information, 24-hour dietary recalls, Yale Food Addiction Scale (YFAS), Eating Attitudes Test-26 (EAT-26), and anthropometric measurements were collected through face-to-face interviews. Overall, 11.4% of participants were identified as "food addicted" (F: 13.0%; M: 9.2%). Subjects meeting criteria for 'food addiction' had higher body mass index (35.1% were obese and 3.1% were underweight), compared to subjects without food addiction (13.1% were obese and 10.2% were underweight) (p<0.05). Abnormal eating attitudes estimated with EAT-26 were determined as 45.5% in males, 37.5% in females and 40.2% in total, among subjects with food addiction. Daily energy, protein and fat intakes were significantly higher in food addicted females, compared to non-addicted females (p<0.05). Participants with food addiction reported significantly more problems with foods, which contain high amounts of fat and sugar, compared to the participants without food addiction. Food addiction behaviour should be considered as a part of efforts towards reducing food related problems involving obesity.

Fatty acid transport receptor soluble CD36 and dietary fatty acid pattern in type 2 diabetic patients: a comparative study.

Recently, it has been remarked that dietary fatty acids and fatty acid receptors might be involved in the aetiology of diabetes. Therefore, this study was conducted to determine the relationship between dietary fatty acid pattern, fatty food preferences and soluble CD36 (sCD36) and insulin resistance in type 2 diabetes mellitus (DM). The study was carried out with thirty-eight newly diagnosed type 2 DM patients and thirty-seven healthy volunteers, aged 30-65 years. In the study, socio-demographic characteristics, dietary fat type and fatty acid pattern of individuals were recorded. After anthropometric measurements were taken, blood CD36, glucose, TAG and insulin levels were analysed. The results showed that although the type of fatty acid intake did not differ between the groups (P>0·05), the consumption of olive oil in the type 2 DM group was lower than the control group (P0·05). Crucially, elevated sCD36 levels increased the type 2 DM risk (OR 1·21, P<0·05). In conclusion, sCD36 level may be a possible biomarker, independent from the dietary fatty acid pattern, for type 2 DM owing to its higher levels in these patients. Therefore, the new insights make CD36 attractive as a therapeutic target for diabetes.

Maternal dietary free or bound fructose diversely influence developmental programming of lipogenesis.

BACKGROUND: Maternal dietary choices throughout preconception, pregnancy, and lactation irreversibly affect the development of fetal tissues and organs, known as fetal programming. Recommendations tend to emphasize reducing added sugars. However, the impact of maternal dietary free or bound fructose in added sugars on developmental programming of lipogenesis is unknown. METHODS: Virgin Sprague-Dawley rats were randomly divided into five groups. Rats were given feed and plain water (control) or water containing maltodextrin (vehicle), fructose, high-fructose corn syrup (HFCS) containing 55% fructose, sucrose (20% w/v) for 12 weeks before mating and throughout the pregnancy and lactation periods. Body weight, water, and feed intake were measured throughout the study. At the end of the lactation period, blood was drawn to determine the fasting levels of glucose, insulin, triglycerides, and non-esterified fatty acids (NEFA) in blood. Triglycerides and acetyl Co-A Carboxylase-1 (ACC1) levels in livers were analyzed, and insulin resistance was calculated. RESULTS: The energy intake of dams in the HFCS group was higher than in the fructose group, while weight gain was less in the HFCS group than in the fructose group. HFCS resulted in greater insulin resistance in dams, whereas free fructose had a robust effect on the fetal programming of insulin resistance. Free fructose and HFCS in the maternal diet increased blood and liver triglycerides and NEFA content in pups. Furthermore, fructose and HFCS exposure increased phosphorylated ACC1 as compared to maltodextrin and control, indicating greater fatty acid synthesis in pups and dams. CONCLUSION: Different types of added sugar in the maternal diet have different metabolic effects on the developmental programming of lipogenesis. Consequently, high fructose intake via processed foods may increase the risk for chronic diseases, and free fructose might contribute to developmental programming of chronic diseases more than bound fructose.

Trends in fluid consumption and beverage choices among adults reveal preferences for ayran and black tea in central Turkey.

AIM: Beverages are globally significant sources of water in the diet. There is a lack of knowledge about fluid intake from beverage and water consumption in Turkey. Thus, the aim of this study was to examine the type of drinks preferred at meals and snacks as well as the daily fluid, beverage and water intakes based on age and gender. METHODS: A cross-sectional survey was administered to 3411 randomly chosen adult participants (n = 1522 male, n = 1919 female) representing the general profile of central Turkey. The survey consisted of a demographic/personal information questionnaire, 24-hour dietary recalls and mealtime-based beverage frequency questionnaires. Body weights and heights were measured. RESULTS: Daily average total fluid consumption was 2270 mL/day, of which water was 1470 mL/day, and other beverages were 800 mL/day. More than 90% of the participants drank black tea at breakfast and snacks. For lunch and dinner, young participants' major choices were carbonated soft drinks followed by ayran (diluted salty plain yoghurt); middle aged and older participants' choices were ayran followed by black tea. Carbonated soft drinks were preferred over ayran in subjects aged 19-39 years. CONCLUSIONS: Older participants prefer healthy, traditional choices such as ayran and black tea, but younger participants prefer high energy-containing drinks with low nutritional value. Thus, this unique information contributes to the data on beverage consumption patterns in different countries and might be useful for increasing consumption of nutritious fluids and decreasing sugar usage in Turkey.

High tendency to the substantial concern on body shape and eating disorders risk of the students majoring Nutrition or Sport Sciences.

BACKGROUND/OBJECTIVES: Studies have indicated that university students majoring in nutrition and dietetics or sport sciences may have more obsessions associated with eating attitudes and body shape perception compared to other disciplines i.e. social sciences. Therefore, this study aimed to assess and compare the risk of eating disorders and body shape perception. MATERIALS/METHODS: Data was collected from 773 undergraduate students at the Departments of Nutrition and Dietetics (NDD) (n = 254), Physical Education and Sports (PESD) (n = 263), and Social Sciences (SOC) (n = 256).A socio-demographic and personal information questionnaire, Eating Attitudes Test (EAT-40), Body Shape Questionnaire (BSQ-34), Perceived Figure Rating Scale (FRS) were applied; and body weights and heights were measured. RESULTS: Mean EAT-40 scores showed that, both male and female students of PESD had the highest scores (17.4 ± 11.6) compared with NDD (14.3 ± 8.3) and SOC (13.0 ± 6.2) (P < 0.05). According to EAT-40 classification, high risk in abnormal eating behavior was more in PESD (10.7%) compared to NDD (2.9%) and SOC (0.4%) students (P < 0.05). Students of PESD, who skipped meal, had higher tendency to the risk of eating disorders (P < 0.05). In parallel, body shape perception was found to be marked with higher scores in NDD (72.0 ± 28.7) and PESD (71.5 ± 32.8) compared with SOC (64.2 ± 27.5) students (P < 0.05). Considering BSQ-34 classification, high concern (moderate and marked) for body shape were more in PESD (7.4 %) compared to NDD (5.2%) and SOC (1.9%) students (P < 0.05). The body size judgement via obtained by the FRS scale were generally correlated with BMI. The Body Mass Index levels were in normal range (Mean BMI: 21.9 ± 2.8 kg/m(2)) and generally consistent with FRS data. CONCLUSIONS: Tendency to the abnormal eating behavior and substantial body shape perception were higher in PESD students who have more concern on body shape and were not well-educated about nutrition. In conclusion, substantial concern on physical appearance might affect eating behavior disorders in PESD students.

Calcium signaling recruits substrate transporters GLUT4 and CD36 to the sarcolemma without increasing cardiac substrate uptake.

Activation of AMP-activated protein kinase (AMPK) in cardiomyocytes induces translocation of glucose transporter GLUT4 and long-chain fatty acid (LCFA) transporter CD36 from endosomal stores to the sarcolemma to enhance glucose and LCFA uptake, respectively. Ca(2+)/calmodulin-activated kinase kinase-ß (CaMKKß) has been positioned directly upstream of AMPK. However, it is unknown whether acute increases in [Ca(2+)]i stimulate translocation of GLUT4 and CD36 and uptake of glucose and LCFA or whether Ca(2+) signaling converges with AMPK signaling to exert these actions. Therefore, we studied the interplay between Ca(2+) and AMPK signaling in regulation of cardiomyocyte substrate uptake. Exposure of primary cardiomyocytes to inhibitors or activators of Ca(2+) signaling affected neither AMPK-Thr(172) phosphorylation nor basal and AMPK-mediated glucose and LCFA uptake. Despite their lack of an effect on substrate uptake, Ca(2+) signaling activators induced GLUT4 and CD36 translocation. In contrast, AMPK activators stimulated GLUT4/CD36 translocation as well as glucose/LCFA uptake. When cardiomyocytes were cotreated with Ca(2+) signaling and AMPK activators, Ca(2+) signaling activators further enhanced AMPK-induced glucose/LCFA uptake. In conclusion, Ca(2+) signaling shows no involvement in AMPK-induced GLUT4/CD36 translocation and substrate uptake but elicits transporter translocation via a separate pathway requiring CaMKKß/CaMKs. Ca(2+)-induced transporter translocation by itself appears to be ineffective to increase substrate uptake but requires additional AMPK activation to effectuate transporter translocation into increased substrate uptake. Ca(2+)-induced transporter translocation might be crucial under excessive cardiac stress conditions that require supraphysiological energy demands. Alternatively, Ca(2+) signaling might prepare the heart for substrate uptake during physiological contraction by inducing transporter translocation.

Supporting roles of platelet thrombospondin-1 and CD36 in thrombus formation on collagen.

OBJECTIVE: Platelets abundantly express the membrane receptor CD36 and store its ligand thrombospondin-1 (TSP1) in the α-granules. We investigated whether released TSP1 can support platelet adhesion and thrombus formation via interaction with CD36. APPROACH AND RESULTS: Mouse platelets deficient in CD36 showed reduced adhesion to TSP1 and subsequent phosphatidylserine expression. Deficiency in either CD36 or TSP1 resulted in markedly increased dissolution of thrombi formed on collagen, although thrombus buildup was unchanged. In mesenteric vessels in vivo, deficiency in CD36 prolonged the time to occlusion and enhanced embolization, which was in agreement with earlier observations in TSP1-deficient mice. Thrombi formed using wild-type blood stained positively for secreted TSP1. Releasate from wild-type but not from TSP1-deficient platelets enhanced platelet activation, phosphatidylserine expression, and thrombus formation on collagen. The enhancement was dependent on CD36 because it was without effect on thrombus formation by CD36-deficient platelets. CONCLUSIONS: These results demonstrate an anchoring role of platelet-released TSP1 via CD36 in platelet adhesion and collagen-dependent thrombus stabilization. Thus, the TSP1-CD36 tandem is another platelet ligand-receptor axis contributing to the maintenance of a stable thrombus.

Atheroprotective effect of dietary walnut intake in ApoE-deficient mice: involvement of lipids and coagulation factors.

INTRODUCTION: Consumption of n-3 polyunsaturated fatty acids (PUFA) and antioxidant polyphenols is considered to decline the risk of cardiovascular disease. MATERIALS AND METHODS: To provide an explanation for this cardioprotective effect, we performed an intervention study with proatherogenic Apoe(-/-) mice which were fed during eight weeks with a high fat diet supplemented with either walnuts (rich in n-3 PUFA and antioxidant compounds), walnut oil (with n-3 PUFA only) or sunflower oil as a control (12 mice per group). RESULTS: Feeding walnuts, but not walnut oil, caused a 55% reduction in atherosclerotic plaque development in the aortic arch in comparison to the control diet. This was associated with reduced staining of plaques for CD36, a scavenger receptor expressed by macrophages. Feeding mice with walnuts also lowered plasma levels of triglycerides, cholesterol and prothrombin with 36%, 23% and 21 %, respectively, compared to control diet. In addition, accumulation of lipids in the liver was decreased, while plasma antioxidant capacity was increased. On the other hand, feeding mice with walnut oil did not provoke significant changes in these parameters in comparison to the control diet. Platelet activation and thrombus formation under flow remained unchanged with either diet. CONCLUSIONS: In Apoe(-/-) mice on high fat diet, intake of dietary walnut (but not walnut oil) beneficially influences lipid metabolism and atherosclerotic plaque development, with no more than limited effects on platelet and coagulation function.

Key role of integrin α(IIb)ß (3) signaling to Syk kinase in tissue factor-induced thrombin generation.

The fibrin(ogen) receptor, integrin α(IIb)ß(3), has a well-established role in platelet spreading, aggregation and clot retraction. How α(IIb)ß(3) contributes to platelet-dependent coagulation is less well resolved. Here, we demonstrate that the potent suppressing effect of clinically used α(IIb)ß(3) blockers on tissue factor-induced thrombin generation is linked to diminished platelet Ca(2+) responses and phosphatidylserine (PS) exposure. The same blockers suppress these responses in platelets stimulated with collagen and thrombin receptor agonists, whereas added fibrinogen potentiates these responses. In platelets spreading on fibrinogen, outside-in α(IIb)ß(3) signaling similarly enhances thrombin-induced Ca(2+) rises and PS exposure. These responses are reduced in α(IIb)ß(3)-deficient platelets from patients with Glanzmann's thrombasthenia. Furthermore, the contribution of α(IIb)ß(3) to tissue factor-induced platelet Ca(2+) rises, PS exposure and thrombin generation in plasma are fully dependent on Syk kinase activity. Tyrosine phosphorylation analysis confirms a key role of Syk activation, which is largely but not exclusively dependent on α(IIb)ß(3) activation. It is concluded that the majority of tissue factor-induced procoagulant activity of platelets relies on Syk activation and ensuing Ca(2+) signal generation, and furthermore that a considerable part of Syk activation relies on α(IIb)ß(3) signaling. These results hence point to a novel role of Syk in integrin-dependent thrombin generation.

Stabilizing role of platelet P2Y(12) receptors in shear-dependent thrombus formation on ruptured plaques.

BACKGROUND: In most models of experimental thrombosis, healthy blood vessels are damaged. This results in the formation of a platelet thrombus that is stabilized by ADP signaling via P2Y(12) receptors. However, such models do not predict involvement of P2Y(12) in the clinically relevant situation of thrombosis upon rupture of atherosclerotic plaques. We investigated the role of P2Y(12) in thrombus formation on (collagen-containing) atherosclerotic plaques in vitro and in vivo, by using a novel mouse model of atherothrombosis. METHODOLOGY: Plaques in the carotid arteries from Apoe(-/-) mice were acutely ruptured by ultrasound treatment, and the thrombotic process was monitored via intravital fluorescence microscopy. Thrombus formation in vitro was assessed in mouse and human blood perfused over collagen or plaque material under variable conditions of shear rate and coagulation. Effects of two reversible P2Y(12) blockers, ticagrelor (AZD6140) and cangrelor (AR-C69931MX), were investigated. PRINCIPAL FINDINGS: Acute plaque rupture by ultrasound treatment provoked rapid formation of non-occlusive thrombi, which were smaller in size and unstable in the presence of P2Y(12) blockers. In vitro, when mouse or human blood was perfused over collagen or atherosclerotic plaque material, blockage or deficiency of P2Y(12) reduced the thrombi and increased embolization events. These P2Y(12) effects were present at shear rates >500 s(-1), and they persisted in the presence of coagulation. P2Y(12)-dependent thrombus stabilization was accompanied by increased fibrin(ogen) binding. CONCLUSIONS/SIGNIFICANCE: Platelet P2Y(12) receptors play a crucial role in the stabilization of thrombi formed on atherosclerotic plaques. This P2Y(12) function is restricted to high shear flow conditions, and is preserved in the presence of coagulation.