Carbon Monoxide Suppresses Neointima Formation in Transplant Arteriosclerosis by Inhibiting Vascular Progenitor Cell Differentiation.

[Figure: see text].

Elevated LDL cholesterol and increased risk of myocardial infarction and atherosclerotic cardiovascular disease in individuals aged 70-100 years: a contemporary primary prevention cohort.

BACKGROUND: Findings of historical studies suggest that elevated LDL cholesterol is not associated with increased risk of myocardial infarction and atherosclerotic cardiovascular disease in patients older than 70 years. We aimed to test this hypothesis in a contemporary population of individuals aged 70-100 years. METHODS: We included in our analysis individuals (aged 20-100 years) from the Copenhagen General Population Study (CGPS) who did not have atherosclerotic cardiovascular disease or diabetes at baseline and who were not taking statins. Standard hospital assays were used to measure LDL cholesterol. We calculated hazard ratios (HRs) and absolute event rates for myocardial infarction and atherosclerotic cardiovascular disease, and we estimated the number needed to treat (NNT) in 5 years to prevent one event. FINDINGS: Between Nov 25, 2003, and Feb 17, 2015, 91 131 individuals were enrolled in CGPS. During mean 7·7 (SD 3·2) years of follow-up (to Dec 7, 2018), 1515 individuals had a first myocardial infarction and 3389 had atherosclerotic cardiovascular disease. Risk of myocardial infarction per 1·0 mmol/L increase in LDL cholesterol was augmented for the overall population (HR 1·34, 95% CI 1·27-1·41) and was amplified for all age groups, particularly those aged 70-100 years. Risk of atherosclerotic cardiovascular disease was also raised per 1·0 mmol/L increase in LDL cholesterol overall (HR 1·16, 95% CI 1·12-1·21) and in all age groups, particularly those aged 70-100 years. Risk of myocardial infarction was also increased with a 5·0 mmol/L or higher LDL cholesterol (ie, possible familial hypercholesterolaemia) versus less than 3·0 mmol/L in individuals aged 80-100 years (HR 2·99, 95% CI 1·71-5·23) and in those aged 70-79 years (1·82, 1·20-2·77). Myocardial infarction and atherosclerotic cardiovascular disease events per 1000 person-years for every 1·0 mmol/L increase in LDL cholesterol were highest in individuals aged 70-100 years, with number of events lower with younger age. The NNT in 5 years to prevent one myocardial infarction or atherosclerotic cardiovascular disease event if all people were given a moderate-intensity statin was lowest for individuals aged 70-100 years, with the NNT increasing with younger age. INTERPRETATION: In a contemporary primary prevention cohort, people aged 70-100 years with elevated LDL cholesterol had the highest absolute risk of myocardial infarction and atherosclerotic cardiovascular disease and the lowest estimated NNT in 5 years to prevent one event. Our data are important for preventive strategies aimed at reducing the burden of myocardial infarction and atherosclerotic cardiovascular disease in the growing population aged 70-100 years. FUNDING: None.

Favorable Effects of GLP-1 Receptor Agonist against Pancreatic ß-Cell Glucose Toxicity and the Development of Arteriosclerosis: "The Earlier, the Better" in Therapy with Incretin-Based Medicine.

Fundamental pancreatic ß-cell function is to produce and secrete insulin in response to blood glucose levels. However, when ß-cells are chronically exposed to hyperglycemia in type 2 diabetes mellitus (T2DM), insulin biosynthesis and secretion are decreased together with reduced expression of insulin transcription factors. Glucagon-like peptide-1 (GLP-1) plays a crucial role in pancreatic ß-cells; GLP-1 binds to the GLP-1 receptor (GLP-1R) in the ß-cell membrane and thereby enhances insulin secretion, suppresses apoptotic cell death and increase proliferation of ß-cells. However, GLP-1R expression in ß-cells is reduced under diabetic conditions and thus the GLP-1R activator (GLP-1RA) shows more favorable effects on ß-cells at an early stage of T2DM compared to an advanced stage. On the other hand, it has been drawing much attention to the idea that GLP-1 signaling is important in arterial cells; GLP-1 increases nitric oxide, which leads to facilitation of vascular relaxation and suppression of arteriosclerosis. However, GLP-1R expression in arterial cells is also reduced under diabetic conditions and thus GLP-1RA shows more protective effects on arteriosclerosis at an early stage of T2DM. Furthermore, it has been reported recently that administration of GLP-1RA leads to the reduction of cardiovascular events in various large-scale clinical trials. Therefore, we think that it would be better to start GLP-1RA at an early stage of T2DM for the prevention of arteriosclerosis and protection of ß-cells against glucose toxicity in routine medical care.

Role of Resident Stem Cells in Vessel Formation and Arteriosclerosis.

Vascular, resident stem cells are present in all 3 layers of the vessel wall; they play a role in vascular formation under physiological conditions and in remodeling in pathological situations. Throughout development and adult early life, resident stem cells participate in vessel formation through vasculogenesis and angiogenesis. In adults, the vascular stem cells are mostly quiescent in their niches but can be activated in response to injury and participate in endothelial repair and smooth muscle cell accumulation to form neointima. However, delineation of the characteristics and of the migration and differentiation behaviors of these stem cells is an area of ongoing investigation. A set of genetic mouse models for cell lineage tracing has been developed to specifically address the nature of these cells and both migration and differentiation processes during physiological angiogenesis and in vascular diseases. This review summarizes the current knowledge on resident stem cells, which has become more defined and refined in vascular biology research, thus contributing to the development of new potential therapeutic strategies to promote endothelial regeneration and ameliorate vascular disease development.

Exercise and Peripheral Arteriosclerosis.

Adaptation of a healthy lifestyle including adequate daily physical activity is shown to reduce 80% of cardiovascular mortality and 40% of cancer-related deaths. A large body of evidence exists proving that this relationship is dose dependent, and even half of the recommended normal physical activity yields significant risk reduction. There has been no medical therapy that would provide such high percentages of reduction in mortality to date. The World Health Organization, therefore, has started an initiative to implement exercise into daily life as a primary prevention measure. Herein, we will focus on the effects of exercise on the vasculature, mainly the peripheral vasculature, in the context of atherosclerotic disease. Exercise has a fundamental role in the pathogenesis, diagnosis, and treatment of atherosclerotic vascular disease. It exerts a protective effect against the development of atherosclerosis irrespective of other cardiovascular risk factors. Additionally, exercise induces changes in vascular hemodynamics helping us to elucidate the presence of obscure vascular involvement. Once again, exercise is the main treatment modality in peripheral arterial disease with accumulating evidence to reduce symptoms and improve both exercise capacity and cardiovascular symptoms.

Cohabiting with Smokers Is an Independent Factor for Worsening Arterial Stiffness Even in Smoking Workers.

Preventing cardiovascular disease (CVD) is an urgent public health challenge. Although brachial-ankle pulse wave velocity (baPWV) can indicate the risk of arterial stiffness and CVD, findings regarding whether baPWV is associated with smoking are inconsistent. This study considered the influence of smoking on arteriosclerosis, specifically focusing on secondhand smoke (SHS), and aimed to construct a strategy for preventing the worsening of arteriosclerosis. We recruited 295 male employees from five companies who had smoking habits such as being smokers, living with smokers, and exposure to SHS outside the home. We measured body composition and hemodynamics, including blood pressure and baPWV, and found that baPWV had significant positive correlations with age, smoking index, alcohol consumption, body-fat percentage, blood pressure, and heart rate, and significant negative correlations with height, fat-free mass, and lower-limb muscle mass. Moreover, baPWV showed a significant adverse effect on participants who had metabolic syndrome (MetS) risk factors such as hypertension, dyslipidemia, and diabetes. Multiple regression analysis showed that baPWV had significant positive relationships with age, height, MetS risk factors, cohabitation with smokers, blood pressure, and heart rate, and a significant negative relationship with lower-limb muscle mass. The same results were obtained when adjusting for current smoking status, smoking index, cohabitation with smokers at birth, and frequency of exposure to SHS outside the home. Exposure to tobacco smoke due to cohabitation with smokers increased baPWV regardless of the person's smoking habits. Thus, to prevent an increase in baPWV in housemates and smokers, it is necessary for smokers to quit smoking.

Correlations Between Glycemic Parameters Obtained from Continuous Glucose Monitoring and Hemoglobin A1c and Glycoalbumin Levels in Type 2 Diabetes Mellitus.

It is difficult to detect glycemic excursions using CGM in daily clinical practice. We retrospectively analyzed CGM data in type T2DM to define the correlations between HbA1c and GA levels at admission and the parameters representing glycemic excursions measured by CGM, including the mean amplitude of glycemic excursions (MAGE) and standard deviation (SD). The MAGE correlated significantly with GA and HbA1c, but not with the GA/HbA1c ratio. The SD correlated significantly with GA, HbA1c, and GA/HbA1c. Multivariate analysis identified the GA value to be the most reflective of MAGE. Patients were divided into 2 groups using a MAGE cutoff value of 75 mg/dl, which reflects stable diabetes. There was a significant difference in GA, but not HbA1c, between the groups with low and high mean amplitudes of glycemic excursions. Receiver operating characteristic curve analysis indicated that the cutoff for GA for identifying patients with MAGE of ≤75 mg/dl was 18.1%. Our study identified GA to be the most reflective of glycemic excursions in patients with T2DM. GA can be a useful index of glycemic excursions and treatment optimization to prevent arteriosclerosis.

Vascular smooth muscle LRP6 limits arteriosclerotic calcification in diabetic LDLR-/- mice by restraining noncanonical Wnt signals.

RATIONALE: Wnt signaling regulates key aspects of diabetic vascular disease. OBJECTIVE: We generated SM22-Cre;LRP6(fl/fl);LDLR(-/-) mice to determine contributions of Wnt coreceptor low-density lipoprotein receptor-related protein 6 (LRP6) in the vascular smooth muscle lineage of male low-density lipoprotein receptor-null mice, a background susceptible to diet (high-fat diet)-induced diabetic arteriosclerosis. METHODS AND RESULTS: As compared with LRP6(fl/fl);LDLR(-/-) controls, SM22-Cre;LRP6(fl/fl);LDLR(-/-) (LRP6-VKO) siblings exhibited increased aortic calcification on high-fat diet without changes in fasting glucose, lipids, or body composition. Pulse wave velocity (index of arterial stiffness) was also increased. Vascular calcification paralleled enhanced aortic osteochondrogenic programs and circulating osteopontin (OPN), a matricellular regulator of arteriosclerosis. Survey of ligands and Frizzled (Fzd) receptor profiles in LRP6-VKO revealed upregulation of canonical and noncanonical Wnts alongside Fzd10. Fzd10 stimulated noncanonical signaling and OPN promoter activity via an upstream stimulatory factor (USF)-activated cognate inhibited by LRP6. RNA interference revealed that USF1 but not USF2 supports OPN expression in LRP6-VKO vascular smooth muscle lineage, and immunoprecipitation confirmed increased USF1 association with OPN chromatin. ML141, an antagonist of cdc42/Rac1 noncanonical signaling, inhibited USF1 activation, osteochondrogenic programs, alkaline phosphatase, and vascular smooth muscle lineage calcification. Mass spectrometry identified LRP6 binding to protein arginine methyltransferase (PRMT)-1, and nuclear asymmetrical dimethylarginine modification was increased with LRP6-VKO. RNA interference demonstrated that PRMT1 inhibits OPN and TNAP, whereas PRMT4 supports expression. USF1 complexes containing the histone H3 asymmetrically dimethylated on Arg-17 signature of PRMT4 are increased with LRP6-VKO. Jmjd6, a demethylase downregulated with LRP6 deficiency, inhibits OPN and TNAP expression, USF1: histone H3 asymmetrically dimethylated on Arg-17 complex formation, and transactivation. CONCLUSIONS: LRP6 restrains vascular smooth muscle lineage noncanonical signals that promote osteochondrogenic differentiation, mediated in part via USF1- and arginine methylation-dependent relays.

Estimating the extent of subclinical arteriosclerosis of persons with prediabetes and diabetes mellitus among Japanese urban workers and their families: a cross-sectional study.

BACKGROUND: Diabetes mellitus (hereafter called diabetes) is considered to accelerate arteriosclerosis leading to coronary heart disease and stroke. Thus, it is important to quantitatively estimate the extent of subclinical arteriosclerosis. A new method called cardio-ankle vascular index (CAVI) is developed to reflect arterial stiffness independently from blood pressure at the time of measurement. Then, we examined if CAVI scores could discriminate the extent of arteriosclerosis between persons with prediabetes (or borderline diabetes) and with diabetes among Japanese urban workers and their families. METHODS: Subjects were 9881 men and 12033 women of company employees and their families who participated in cardiovascular disease screening in Japan. Persons having diabetes and prediabetes were defined based on the criteria set by American Diabetes Association. CAVI scores were measured by VaSera VS-1000. We applied the established age-sex specific cutoff points of CAVI scores above which were determined to be abnormally high or advanced level of arteriosclerosis. To examine the association of prediabetes and diabetes with CAVI scores, CAVI scores of screening participants were converted to a binary variable: 1 for less than cutoff points and 2 for equal or greater than cutoff points or abnormally high CAVI scores. Logistic regression method was used to examine the association of prediabetes and diabetes with CAVI scores after adjusting for major cardiovascular disease (CVD) risk factors. RESULTS: Prevalence of abnormally high CAVI scores was significantly higher after 40 years of age among persons with diabetes than either among persons with prediabetes or among normal persons in both genders. Significantly elevated odds ratios (ORs) of abnormally high CAVI scores appeared among persons with prediabetes: 1.29 (95 % confidence interval (CI), 1.11-1.48) for men and 1.14 (CI, 1.01-1.28) for women, and among persons with diabetes: 2.41 (CI, 1.97-2.95) for men and 2.52 (CI, 1.94-3.28) for women. CONCLUSIONS: The extent of subclinical arteriosclerosis (including arterial stiffness and atherosclerosis) was moderately enhanced among persons with prediabetes and was further advanced among persons with diabetes. Thus, it is important to introduce earlier interventions for changing lifestyle and diet of persons with prediabetes in order to prevent them from developing diabetes and further advancing arteriosclerosis.

Serum ß-cryptoxanthin and ß-carotene derived from Satsuma mandarin and brachial-ankle pulse wave velocity: The Mikkabi cohort study.

BACKGROUND AND AIMS: Findings of observational studies suggest cardioprotective effects of antioxidant vitamins and carotenoids. However, recent meta-analyses failed to show the beneficial effects of supplemental intake of antioxidants on cardiovascular disease (CVD). We aimed to assess the association between CVD risk and ß-cryptoxanthin in Japan, where Satsuma mandarin, a major source of ß-cryptoxanthin, is widely consumed. METHODS AND RESULTS: This was part of the Mikkabi cohort study. Surveys were conducted at baseline, in 2003 and 2005, and on follow-up in 2006, 2009, and 2013. We examined brachial-ankle pulse wave velocity (baPWV) with a high cut-off value set at 18.3 m s(-1). Hazard ratios (HR) and 95% confidence intervals for high baPWV were estimated using a Cox proportional hazards model with adjustment for potential confounders. A total of 635 participants with baPWV of less than 18.3 m s(-1) at baseline were included in the analysis. During the follow-up period of 57,921 person-months, 99 subjects developed high baPWV. After multivariate adjustment, the HR for high baPWV in the highest tertile compared with the lowest tertile was significantly low for ß-cryptoxanthin, ß-carotene, and total carotenoids. Serum concentrations of ß-cryptoxanthin and ß-carotene were higher in people who ate Satsuma mandarin frequently. Compared with <1/d intake of Satsuma mandarin, 3-4/d was associated with a low risk of high PWV. CONCLUSION: This study indicated that ß-cryptoxanthin and ß-carotene derived from Satsuma mandarin are candidate micronutrients for preventing arteriosclerosis development. Further longitudinal and interventional studies will be required to validate the effect on CVD.

Acetylsalicylic acid (ASA) - How much, how often, and when? A clinical-pharmacological perspective.

The dose of acetylsalicylic acid (ASA) commonly used in the prevention and treatment of arteriosclerotic angiopathies is equal to or less than 100 mg daily. This choice of dose is predominantly based on molecular-pharmacological findings showing an inhibition in synthesis of the prothrombotic thromboxane (TXB2) and an irreversible inhibition in blood platelet aggregation. However, an analysis of ASA dose-effect relationships for doses of 50 - 500 mg (PO and IV) shows that doses of ASA up to 100 mg daily produce only a small or moderate inhibition in collagen/epinephrine-induced platelet aggregation and have no significant effect on the important platelet factors, PF3 and PF4. Doses of ASA 300 - 500 mg, on the other hand, inhibit platelet aggregation almost completely and, in addition, produce a 50 - 70% inhibition in PF3 and PF4 lasting at least 24 hours. There is also evidence that doses of ASA above 100 mg daily markedly inhibit thromboxane synthesis for up to 24 hours and that doses of 500 mg daily produce a clinically relevant inhibition in platelet adhesion to vessel walls for up 72 hours and prevent procoagulatory shape changes for up to 12 hours. These findings suggest that a dose of ≥ 300 mg at intervals of 2 - 3 days would be more appropriate for primary and secondary prophylaxis of arteriosclerotic angiopathies and that the benefit-risk ratio would be greater because of the increased availability of mucoprotective prostaglandins, PGI2 (prostacyclin) and the gastroprotective, PGE2. Our viewpoint, predominantly based on findings with biomarkers, could serve as a basis for further randomized controlled studies.

The Sirt1 activator SRT3025 provides atheroprotection in Apoe-/- mice by reducing hepatic Pcsk9 secretion and enhancing Ldlr expression.

AIMS: The deacetylase sirtuin 1 (Sirt1) exerts beneficial effects on lipid metabolism, but its roles in plasma LDL-cholesterol regulation and atherosclerosis are controversial. Thus, we applied the pharmacological Sirt1 activator SRT3025 in a mouse model of atherosclerosis and in hepatocyte culture. METHODS AND RESULTS: Apolipoprotein E-deficient (Apoe(-/-)) mice were fed a high-cholesterol diet (1.25% w/w) supplemented with SRT3025 (3.18 g kg(-1) diet) for 12 weeks. In vitro, the drug activated wild-type Sirt1 protein, but not the activation-resistant Sirt1 mutant; in vivo, it increased deacetylation of hepatic p65 and skeletal muscle Foxo1. SRT3025 treatment decreased plasma levels of LDL-cholesterol and total cholesterol and reduced atherosclerosis. Drug treatment did not change mRNA expression of hepatic LDL receptor (Ldlr) and proprotein convertase subtilisin/kexin type 9 (Pcsk9), but increased their protein expression indicating post-translational effects. Consistent with hepatocyte Ldlr and Pcsk9 accumulation, we found reduced plasma levels of Pcsk9 after pharmacological Sirt1 activation. In vitro administration of SRT3025 to cultured AML12 hepatocytes attenuated Pcsk9 secretion and its binding to Ldlr, thereby reducing Pcsk9-mediated Ldlr degradation and increasing Ldlr expression and LDL uptake. Co-administration of exogenous Pcsk9 with SRT3025 blunted these effects. Sirt1 activation with SRT3025 in Ldlr(-/-) mice reduced neither plasma Pcsk9, nor LDL-cholesterol levels, nor atherosclerosis. CONCLUSION: We identify reduction in Pcsk9 secretion as a novel effect of Sirt1 activity and uncover Ldlr as a prerequisite for Sirt1-mediated atheroprotection in mice. Pharmacological activation of Sirt1 appears promising to be tested in patients for its effects on plasma Pcsk9, LDL-cholesterol, and atherosclerosis.

In Vitro and in Vivo Atheroprotective Effects of Gossypetin against Endothelial Cell Injury by Induction of Autophagy.

Oxidized low-density lipoprotein (ox-LDL) contributes to the pathogenesis of atherosclerosis by promoting vascular endothelial cell injury.Gossypetin, a naturally occurring hexahydroxyflavone, has been shown to possess antimutagenic, antioxidant, antimicrobial, and antiatherosclerotic effects. In this study, the atheroprotective role of gossypetin was examined in endothelial cells. The protective effect of gossypetin against ox-LDL-induced injury in human umbilicalvein endothelial cells (HUVECs) was first noted at 0.1−0.5 µM. Gossypetin showed potential in reducing ox-LDL-dependent apoptosis, as demonstrated by morphological and biochemical features, including formation of apoptotic bodies,distribution of hypodiploid phase, and activation of caspase-3. Next, the ox-LDL induced formation of acidic vesicular organelles and the upregulation of autophagyrelated genes (LC3 and Beclin-1) were enhanced by gossypetin. Gossypetin triggered autophagic flux was further confirmed by an increase in the level of LC3-II under pretreatment conditions with an autophagy inhibitor, chloroquine (CQ). In addition, silencing Beclin-1 inhibited both the gossypetin-mediated protective affects and the autophagic process. Molecular data indicated that the autophagic effect of gossypetin might be mediated via the class III PI3K/Beclin-1 and PTEN/class I PI3K/Akt signaling cascades, as demonstrated by the use of a class III PI3K inhibitor, 3-methyladenine (3-MA), and a PTEN inhibitor, SF1670. Finally, gossypetin improved atherosclerotic lesions and endothelial injury in vivo. These data imply that gossypetin upregulates the autophagic pathway, which led to subsequent reduction of ox-LDL-induced atherogenic endothelial cell injury and apoptosis, and provide a new mechanism for the antiatherosclerotic activity of gossypetin.

Effects of empagliflozin on blood pressure and markers of arterial stiffness and vascular resistance in patients with type 2 diabetes.

AIMS: To determine the effects of empagliflozin on blood pressure (BP) and markers of arterial stiffness and vascular resistance in patients with type 2 diabetes mellitus (T2DM). METHODS: We conducted a post hoc analysis of data from a phase III trial in patients with T2DM and hypertension receiving 12 weeks' empagliflozin and four phase III trials in patients with T2DM receiving 24 weeks' empagliflozin (cohort 1, n = 823; cohort 2, n = 2477). BP was measured using 24-h BP monitoring (cohort 1) or seated office measurements (cohort 2). RESULTS: Empagliflozin reduced systolic BP (SBP) and diastolic BP in both cohorts (p < 0.001 vs placebo), without increasing heart rate. Empagliflozin reduced pulse pressure (PP; adjusted mean difference vs placebo cohort 1: -2.3 mmHg; cohort 2: -2.3 mmHg), mean arterial pressure (MAP; cohort 1, -2.3 mmHg; cohort 2, -2.1 mmHg) and double product (cohort 1, -385 mmHg × bpm; cohort 2, -369 mmHg × bpm) all p < 0.001 vs placebo. There was a trend towards a reduction in the ambulatory arterial stiffness index (AASI) with empagliflozin in cohort 1 (p = 0.059 vs placebo). AASI was not measured in cohort 2. Subgroup analyses showed that there were greater reductions in PP with increasing baseline SBP in cohort 1 (p = 0.092). In cohort 2, greater reductions in MAP were achieved in patients with higher baseline SBP (p = 0.027) and greater reductions in PP were observed in older patients (p = 0.011). CONCLUSIONS: Empagliflozin reduced BP and had favourable effects on markers of arterial stiffness and vascular resistance.

Prostaglandin E2 potentiates mesenchymal stem cell-induced IL-10+IFN-γ+CD4+ regulatory T cells to control transplant arteriosclerosis.

Mesenchymal stem cells (MSCs) are known for their immunomodulatory functions. We previously demonstrated that bone marrow-derived MSCs effectively control transplant arteriosclerosis (TA) by enhancing IL-10(+) and IFN-γ(+) cells. The objective of this study is to elucidate the mechanism by which MSCs induce IL-10(+)IFN-γ(+)CD4(+) regulatory T type 1 (T(R)1)-like cells. In an MLR system using porcine PBMCs, MSC-induced IL-10(+)IFN-γ(+)CD4(+) cells, which confer resistance to allogeneic proliferation in an IL-10-dependent manner, resemble T(R)1-like cells. Both cyclooxygenase-derived PGE(2) and IDO help to induce T(R)1-like cells by MSCs. MSCs constitutively secrete PGE(2), which is augmented in allogeneic reactions. However, T(R)1-like cells were deficient in PGE(2) and 4-fold less potent than were MSCs in suppressing MLR. PGE(2) mimetic supplements can enhance the immunosuppressive potency of T(R)1-like cells. In a porcine model of allogeneic femoral arterial transplantation, MSC-induced T(R)1-like cells combined with PGE(2), but not either alone, significantly reduced TA at the end of 6 wk (percentage of luminal area stenosis: T(R)1-like cells + PGE(2): 11 ± 10%; PGE(2) alone: 93 ± 8.7%; T(R)1-like cells alone: 88 ± 2.4% versus untreated 94 ± 0.9%, p < 0.001). These findings indicate that PGE(2) helps MSC-induced IL-10(+)IFN-γ(+)CD4(+) T(R)1-like cells inhibit TA. PGE(2) combined with MSC-induced T(R)1-like cells represents a new approach for achieving immune tolerance.

Translation of two aggregated low-density lipoproteins within blood plasma: a mathematical model.

Arteriosclerosis is a disease in which the artery walls get thicker and harder. Atherosclerosis is a specific form of arteriosclerosis which allows less blood to travel through the artery and increases blood pressure. Low-density lipoproteins (LDLs) and their ability to aggregate are important in atherosclerosis. In the present study we develop a mathematical model that describes the translation of two aggregated LDSs through blood plasma. We model the two aggregated LDLs as an inverted oblate spheroid and the flow as a creeping steady incompressible axisymmetric one. The mathematical tools that we used are the Kelvin inversion and the semi-separation of variables in the spheroidal coordinate systems. The stream function is given as a series expansion of even order terms of combinations of Gegenbauer functions of angular and radial dependence. The analytical solution is expected to give insight into the study of the various chemical precipitation methods used for the precipitation of lipoproteins, as this is the first step for the measurement of their concentration within blood plasma.

Insulin-like growth factor-1 regulates glutathione peroxidase expression and activity in vascular endothelial cells: Implications for atheroprotective actions of insulin-like growth factor-1.

Oxidative stress promotes endothelial cell senescence and endothelial dysfunction, important early steps in atherogenesis. To investigate potential antioxidant effects of IGF-1 we treated human aortic endothelial cells (hAECs) with 0-100ng/mL IGF-1 prior to exposure to native or oxidized low-density lipoprotein (oxLDL). IGF-1 dose- and time- dependently reduced basal- and oxLDL-induced ROS generation. IGF-1 did not alter superoxide dismutase or catalase activity but markedly increased activity of glutathione peroxidase (GPX), a crucial antioxidant enzyme, via a phosphoinositide-3 kinase dependent pathway. IGF-1 did not increase GPX1 mRNA levels but increased GPX1 protein levels by 2.6-fold at 24h, and altered selenocysteine-incorporation complex formation on GPX1 mRNA. Furthermore, IGF-1 blocked hydrogen peroxide induced premature cell senescence in hAECs. In conclusion, IGF-1 upregulates GPX1 expression in hAECs via a translational mechanism, which may play an important role in the ability of IGF-1 to reduce endothelial cell oxidative stress and premature senescence. Our findings have major implications for understanding vasculoprotective effects of IGF-1.

MHC class I signaling: new functional perspectives for an old molecule.

Donor-specific antibodies are associated with refractory rejection episodes and poor allograft outcomes in solid organ transplantation. Our understanding of antibody-mediated allograft injury is expanding beyond complement deposition. In fact, unique mechanisms of alloantibodies are advancing our knowledge about transplant vasculopathy and antibody-mediated rejection. These include direct effects on the endothelium, resulting in the recruitment of leukocytes, chemokine and cytokine production, and stimulation of innate and adaptive alloresponses. These effects will be the focus of the following review.

[From the Point of View of Health Evaluation and Promotion (Ningen Dock) Facilities].

Since the direct method of LDL measurement is easy and convenient, many health evaluation and promotion facilities adopted it without sufficient discussion after specific health checkups started in Japan. For the purpose of reliable, specific health checkup data, we must review the methods and standardization of LDL measurement. I hope that medical societies, the Ministry of Health, Labour and Welfare, and reagent manufacturers will collaborate.