Attenuation of inflammation with short-term dietary intervention is associated with a reduction of arterial stiffness in subjects with hypercholesterolaemia:

The Association between Inflammation and Pulse Wave Velocity in Dyslipidemia: An Evidence-Based Review

Dyslipidemia is associated with increased arterial stiffness (AS) which may lead to hypertension. Among the methods to assess AS are carotid-femoral and brachial-ankle pulse wave velocity. Dyslipidemia is also known to trigger inflammation. C-reactive protein (CRP) is one of the commonest inflammatory markers measured in the clinical setting. However, the association between inflammation and pulse wave velocity (PWV) in people with dyslipidemia is less studied. Therefore, this review investigated the association between inflammation (as measured by CRP) and PWV in dyslipidemia patients. The search of the literature was conducted via PubMed and Scopus database. The keywords used were "aortic stiffness" OR "arterial stiffness" OR "pulse wave velocity" OR "vascular stiffness" OR "carotid femoral pulse wave velocity" OR "pulse wave analysis" AND "inflammation" OR "c reactive protein" OR "c-reactive protein" OR "high sensitivity c reactive protein" AND "dyslipidemia" OR "hyperlipidemia" OR "hypercholesterolemia" OR "hyperlipoproteinemia" OR "hypertriglyceridemia". The following criteria were used: (1) only full-length original articles published in English language, (2) articles that reported the association between arterial stiffness measured as carotid-femoral PWV (cfPWV) or brachial-ankle PWV (baPWV) and CRP or high-sensitivity CRP, and (3) study involving human subjects. The search identified 957 articles published between 1980 and February 2020. Only eight articles fulfilled the inclusion criteria and were used for data extraction. Five of the studies were cross-sectional studies while another three studies were interventional studies. Seven out of eight papers found a significant positive association between AS and CRP, and the correlation ranged from mild to moderate association (Pearson r = 0.33 to r = 0.624). In conclusion, inflammation is associated with increased PWV in patients with dyslipidemia. This supports the involvement of inflammation in the development of AS in dyslipidemia.

Effects of antiretroviral therapy on proprotein convertase subtilisin/kexin 9: focus on lipids, inflammation and immunovirological parameters

OBJECTIVES

Plasma levels of proprotein convertase subtilisin/kexin type 9 (PCSK9), a major regulator of cholesterol metabolism, have been reported to have an increasing trend in people living with HIV (PLWH) compared with controls. We assessed the impact of different antiretroviral (ARV) regimens on plasma PCSK9 levels as well as plasma lipids, systemic inflammation and immunovirological parameters.

METHODS

Eighty HIV-positive ARV therapy (ART)-naïve PLWH and 40 uninfected controls were retrospectively enrolled. At baseline and 3, 6 and 12 months after ART initiation, plasma PCSK9 levels, lipids, high-sensitivity C-reactive protein (hs-CRP), HIV-1 RNA levels and CD4 T-cell count were measured.

RESULTS

Baseline PCSK9 levels were significantly more elevated in PLWH and were associated with HIV-1 RNA levels (P < 0.001), CD4 T-cell counts (P < 0.001), triglycerides (P < 0.001) and high-density lipoprotein (HDL) cholesterol (P < 0.001), but not with total cholesterol, low-density lipoprotein (LDL) cholesterol and lipoprotein(a) levels. The prescription of ART was paralleled by significant decreases in plasma PCSK9 and hs-CRP levels, and increases in total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides and lipoprotein(a), independent of regimen.

CONCLUSIONS

PCSK9 levels, along with systemic inflammation, were progressively reduced following the initiation of an effective ART. However, at the end of the study PCSK9 levels remained higher than in controls and did not correlate with any of the lipid variables.

Effect of egg consumption on inflammatory markers: a systematic review and meta-analysis of randomized controlled clinical trials

There is little evidence about whether eggs affect inflammation. The aim of this meta-analysis was to explore the effects of egg consumption on inflammation. A systematic search of online databases (Institute for Scientific Information (ISI), Scopus, Ovid, PubMed, Cochrane) was used to gather clinical trials that assessed the effect of egg consumption on circulating inflammatory biomarkers. Using a random-effects model, pooled weighted mean differences (WMD) and corresponding standard deviations (SD) were calculated. Of the 21 eligible studies found, nine trials were eligible for analysis. Eight trials assessed high-sensitivity C-reactive protein (hs-CRP), four trials assessed interleukin-6 (IL-6), and five trials assessed tumor necrosis factor-alpha (TNF-α). Egg consumption did not affect hs-CRP (WMD 0.24 mg/L; 95% CI: -0.43, 0.90; I²  = 53.8; P = 0.48), IL-6 (WMD 0.20 pg/mL; 95% CI: -0.71, 1.11; I² = 69.3; P = 0.50), and TNF-α (WMD: -0.38 pg/mL; 95% CI: -0.87, 0.10; I² = 0.00; P = 0.12) relative to controls. Overall, this meta-analysis revealed that egg consumption had no significant effect on serum biomarkers of inflammation in adults. © 2019 Society of Chemical Industry.

Immunobiology of Atherosclerosis: A Complex Net of Interactions

Cardiovascular disease is the leading cause of mortality worldwide, and atherosclerosis the principal factor underlying cardiovascular events. Atherosclerosis is a chronic inflammatory disease characterized by endothelial dysfunction, intimal lipid deposition, smooth muscle cell proliferation, cell apoptosis and necrosis, and local and systemic inflammation, involving key contributions to from innate and adaptive immunity. The balance between proatherogenic inflammatory and atheroprotective anti-inflammatory responses is modulated by a complex network of interactions among vascular components and immune cells, including monocytes, macrophages, dendritic cells, and T, B, and foam cells; these interactions modulate the further progression and stability of the atherosclerotic lesion. In this review, we take a global perspective on existing knowledge about the pathogenesis of immune responses in the atherosclerotic microenvironment and the interplay between the major innate and adaptive immune factors in atherosclerosis. Studies such as this are the basis for the development of new therapies against atherosclerosis.

The Role of Mesenchymal Stem Cells in Atherosclerosis: Prospects for Therapy via the Modulation of Inflammatory Milieu

Atherosclerosis is a chronic, inflammatory disease that mainly affects the arterial intima. The disease is more prevalent in middle-age and older individuals with one or more cardiovascular risk factors, including dyslipidemia, hypertension, diabetes, smoking, obesity, and others. The beginning and development of atherosclerosis has been associated with several immune components, including infiltration of inflammatory cells, monocyte/macrophage-derived foam cells, and inflammatory cytokines and chemokines. Mesenchymal stem cells (MSCs) originate from several tissue sources of the body and have self-renewal and multipotent differentiation characteristics. They also have immunomodulatory and anti-inflammatory properties. Recently, it was shown that MSCs have a regulatory role in plasma lipid levels. In addition, MSCs have shown to have promising potential in terms of treatment strategies for several diseases, including those with an inflammatory component. In this regard, transplantation of MSCs to patients with atherosclerosis has been proposed as a novel strategy in the treatment of this disease. In this review, we summarize the current advancements regarding MSCs for the treatment of atherosclerosis.

PCSK9 and atherosclerosis burden in the coronary arteries of patients undergoing coronary angiography

AIMS

To investigate the association between plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) concentrations, current acute coronary syndrome (ACS), coronary artery disease (CAD) presence, severity and extension and the burden of coronary calcifications in patients with suspected CAD.

METHODS AND RESULTS

One hundred and one patients, with or without current ACS, were recruited for this cross-sectional study. CAD presence was defined based on either the presence or absence of at least one significant (≥50%) CAD lesion (SCAD). CAD severity was classified according to the absence of coronary lesions, the presence of non-significant (<50%) CAD (MCAD) or SCAD in at least one major coronary artery. Patients with one, two or three significantly diseased major coronary arteries were defined as 1-SCAD, 2-SCAD and 3-SCAD, respectively. The cumulative length of SCAD lesions and the amount of calcifications in coronary arteries were estimated. Plasma PCSK9 concentrations were higher in patients with SCAD as compared to those without (p = .012). A significant increase in plasma PCSK9 concentrations was observed with greater CAD severity (p = .042). Higher plasma PCSK9 concentrations were found in 3-SCAD patients as compared to either 2-SCAD or 1-SCAD (p < .001). PCSK9 increased with the cumulative length of SCAD lesions and the burden of calcifications (p < .05 for both comparisons). Multivariable adjustment abolished the association between PCSK9 and either CAD presence or severity, but not the association between PCSK9 and the number of significantly diseased vessels, SCAD lesion length and the burden of coronary calcifications. ACS was associated with a borderline significant increase of plasma PCSK9 concentrations among patients not taking statins (p = .05).

CONCLUSION

Circulating PCSK9 concentrations discriminate patients with greater coronary atherosclerotic lesion extension and calcification, and are increased in patients with current ACS.

Emerging roles for high-density lipoproteins in neurodegenerative disorders

Lipoproteins are the complexes of different lipids and proteins, which are devoted to the transport and clearance of lipids or lipid-related molecules in the circulation. Lipoproteins have been found to play a crucial role in brain function and may influence myelination process. Among lipoproteins, high-density lipoproteins (HDLs) and their major protein component, apoA-I, are directly involved in cholesterol efflux in the brain. It has been suggested that inadequate or dysfunctional brain HDLs may contribute to cerebrovascular dysfunctions, neurodegeneration, or neurovascular instability. HDL deficiency could also promote cognitive decline through impacting on atherosclerotic risk. The focus of this review is to discuss knowledge on HDL dysregulation in neurological disorders. A better understanding on how changes in cellular HDL and apolipoprotein homeostasis affect central nervous system function may provide promising novel avenues for the treatment of specific HDL-related neurological disorders.

Breakfast association with arterial stiffness and carotid atherosclerotic burden. Insights from the 'Corinthia' study

BACKGROUND AND AIMS

The role of dietary patterns, in cardiovascular diseases has been challenged. The role of breakfast as an element of balance energy intake has gained research interest. However, the effects of dietary patterns related to breakfast consumption on vascular function are unknown. We explored the association of breakfast consumption habits with arterial wall elastic properties and carotid atherosclerosis.

METHODS AND RESULTS

In this cross-sectional study we enrolled 2043 inhabitants of the Corinthia region in Greece. Carotid-femoral pulse wave velocity (cf-PWV) was used to assess arterial stiffness. Carotid intima-media thickness (cIMT) was measured and the mean and the maximum cIMT were calculated. According to food frequency questionnaires, breakfast contribution in total daily energy intake (>20%; 5-20% and <5%) was estimated. Subjects were categorized as high-energy breakfast consumers (HeBC), low-energy breakfast consumers (LeBC) and those skipping breakfast (SBf) respectively. From the study population 240 subjects were categorized as HeBC, 897 as LeBC, and 681 as SBf. The mean cf-PWV was significantly higher in subjects SBf compared to LeBC and HeBC (9.35 ± 2.82 m/s vs. 9.09 ± 2.77 m/s vs. 8.76 ± 2.69 m/s, p = 0.02). The mean cIMT was significantly higher in subjects SBf compared to LeBC and HeBC (1.04 ± 0.46 mm vs. 0.99 ± 0.43 mm vs. 0.92 ± 0.39 mm, p = 0.01). Even after adjustment for potential confounders and cardiovascular risk factors SBf subjects have significantly increased mean cIMT and cf-PWV.

CONCLUSION

Skipping breakfast has an adverse effect on arterial stiffness and carotid atheromatic burden. Increased breakfast total energy intake may act protectively against atherosclerosis, a finding worth of further pathophysiologic exploration with potential clinical implications.

Biological properties of metal complexes of curcumin

Curcumin, a naturally occurring phenolic compound isolated from Curcuma longa, has different pharmacological effects, including antiinflammatory, antimicrobial, antioxidant, and anticancer properties. However, curcumin has been found to have a limited bioavailability because of its hydrophobic nature, low-intestinal absorption, and rapid metabolism. Therefore, there is a need for enhancing the bioavailability and its solubility in water in order to increase the pharmacological effects of this bioactive compound. One strategy is curcumin complexation with transition metals to circumvent the abovementioned problems. Curcumin can undergo chelation with various metal ions to form metallo-complexes of curcumin, which may show greater effects as compared with curcumin alone. Promising results with metal curcumin complexes have been observed with regard to antioxidant, anticancer, and antimicrobial activity, as well as in treatment of Alzheimer's disease. The present review provides a concise summary of the characterization and biological properties of curcumin-metal complexes. © 2019 BioFactors, 45(3):304-317, 2019.

Chitosan-based delivery systems for curcumin: A review of pharmacodynamic and pharmacokinetic aspects

Effective drug delivery is one of the most important issues associated with the administration of therapeutic agents that have low oral bioavailability. Curcumin is an active ingredient in the turmeric plant, which has low oral bioavailability due to its poor aqueous solubility. One strategy that has been considered for enhancing the aqueous solubility, and, thus, its oral bioavailability, is the use of chitosan as a carrier for curcumin. Chitosan is a biodegradable and biocompatible polymer that is relatively water-soluble. Therefore, various studies have sought to improve the aqueous solubility of chitosan. The use of different pharmaceutical excipients and formulation strategies has the potential to improve aqueous solubility, formulation processing, and the overall delivery of hydrophobic drugs. This review focuses on various methods utilized for chitosan-based delivery of curcumin.

Effect of Statin Therapy on Arterial Wall Inflammation Based on 18F-FDG PET/CT: A Systematic Review and Meta-Analysis of Interventional Studies

Aim. To evaluate by meta-analysis of interventional studies the effect of statin therapy on arterial wall inflammation. Background. Arterial exposure to low-density lipoprotein (LDL) cholesterol levels is responsible for initiation and progression of atherosclerosis and arterial wall inflammation. 18F-fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (18F-FDG PET/CT) has been used to detect arterial wall inflammation and monitor the vascular anti-inflammatory effects of lipid-lowering therapy. Despite a number of statin-based interventional studies exploring 18F-FDG uptake, these trials have produced inconsistent results. Methods. Trials with at least one statin treatment arm were searched in PubMed-Medline, SCOPUS, ISI Web of Knowledge, and Google Scholar databases. Target-to-background ratio (TBR), an indicator of blood-corrected 18F-FDG uptake, was used as the target variable of the statin anti-inflammatory activity. Evaluation of studies biases, a random-effects model with generic inverse variance weighting, and sensitivity analysis were performed for qualitative and quantitative data assessment and synthesis. Subgroup and meta-regression analyses were also performed. Results. Meta-analysis of seven eligible studies, comprising 10 treatment arms with 287 subjects showed a significant reduction of TBR following statin treatment (Weighted Mean Difference (WMD): −0.104, p = 0.002), which was consistent both in high-intensity (WMD: −0.132, p = 0.019) and low-to-moderate intensity statin trials (WMD: −0.069, p = 0.037). Statin dose/duration, plasma cholesterol and C-reactive protein level changes, and baseline TBR did not affect the TBR treatment response to statins. Conclusions. Statins were effective in reducing arterial wall inflammation, as assessed by 18F-FDG PET/CT imaging. Larger clinical trials should clarify whether either cholesterol-lowering or other pleiotropic mechanisms were responsible for this effect.

NUtraceutical TReatment for hYpercholesterolemia in HIV-infected patients: The NU-TRY(HIV) randomized cross-over trial

BACKGROUND AND AIMS

Despite hypercholesterolemia has been recognized to increase cardiovascular risk in human immunodeficiency virus (HIV)-infected patients, cholesterol-lowering therapy is underused in this population, due to fear of drug-drug interactions with antiretroviral therapy (ART). We investigated the effects of a nutraceutical combination (NC) on lipid profile, proprotein convertase subtilisin/kexin type 9 (PCSK9), subclinical inflammation and arterial stiffness in ART-treated HIV-infected patients.

METHODS

This was a prospective randomized open-label trial with a cross-over design including 30 stable HIV-infected patients on ART with low-density lipoprotein cholesterol (LDL-C) >115 mg/dL, not taking lipid-lowering treatment. After a 3-week lipid stabilization period, the effects associated with 3 months of an oral NC containing red yeast rice and berberine vs. no active treatment (noNC) were assessed for plasma total cholesterol (TC), LDL-C, high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), lipoprotein(a), PCSK9, high-sensitivity C-reactive protein (hs-CRP) levels and aortic pulse wave velocity (aPWV).

RESULTS

At baseline, significant correlations between PCSK9 levels, age (rho = -0.51, p=0.004), waist circumference (rho = 0.36, p=0.005) and CD4⁺ cell count (rho = -0.40, p=0.027) were observed. NC treatment effects corrected for noNC were significant for TC (-14%, p<0.001), LDL-C (-19%, p<0.001), PCSK9 (-12%, p=0.02), hs-CRP (-14%, p=0.03) and aPWV (-6%, p=0.005). No significant effects were observed for HDL-C, TG and lipoprotein(a). NC treatment was safe and no significant alterations in muscle, liver and immunovirological parameters were observed. No carry over effect was recorded.

CONCLUSIONS

The tested NC significantly reduced plasma cholesterol and PCSK9 levels, attenuated subclinical inflammation and improved arterial stiffness in stable HIV-infected patients on ART.

A review of the anti-inflammatory properties of antidiabetic agents providing protective effects against vascular complications in diabetes

The global prevalence of Type 2 diabetes mellitus and its associated complications are growing rapidly. Although the role of hyperglycemia is well recognized in the pathophysiology of diabetic complications, its exact underlying mechanisms are not fully understood. In this regard, accumulating evidence suggests that the role of inflammation appears pivotal, with studies showing that most diabetic complications are associated with an inflammatory response. Several classes of antidiabetic agents have been introduced for controlling glycemia, with evidence that these pharmacological agents may have modulatory effects on inflammation beyond their glucose-lowering activity. Here we review the latest evidence on the anti-inflammatory effects of commonly used antidiabetic medications and discuss the relevance of these effects on preventing diabetic complications.

Diet-Modulated Lipoprotein Metabolism and Vascular Inflammation Evaluated by 18F-fluorodeoxyglucose Positron Emission Tomography

Vascular inflammation plays a central role in atherosclerosis, from initiation and progression to acute thrombotic complications. Modified low-density lipoproteins (LDLs) and apoB-containing particles stimulate plaque inflammation by interacting with macrophages. Loss of function of high-density lipoprotein (HDL) for preventing LDL particles from oxidative modification in dyslipidemic states may amplify modified LDL actions, accelerating plaque inflammation. Diets are one of the most important factors that can affect these processes of lipoprotein oxidation and vascular inflammation. Recently, ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has emerged as a reliable noninvasive imaging modality for identifying and quantifying vascular inflammation within atherosclerotic lesions based on the high glycolytic activity of macrophages infiltrating active atherosclerotic plaques. Vascular inflammation evaluated by FDG PET has been positively related to metabolic syndrome components and traditional risk factors of cardiovascular disease, including high-sensitivity C-reactive protein, body mass index, and insulin resistance. A positive association of vascular inflammation with endothelial dysfunction, resistin levels, pericardial adipose tissue, and visceral fat area has also been reported. In contrast, HDL cholesterol and adiponectin have been inversely related to vascular inflammation detected by FDG PET. Because of its reproducibility, serial FDG PET shows potential for tracking the effects of dietary interventions and other systemic and local antiatherosclerotic therapies for plaque inflammation.

Immune modulation by curcumin: The role of interleukin-10

Cytokines are small secreted proteins released by different types of cells with specific effects on cellular signaling and communication via binding to their receptors on the cell surface. IL-10 is known to be a pleiotropic and potent anti-inflammatory and immunosuppressive cytokine that is produced by both innate and adaptive immunity cells including dendritic cells, macrophages, mast cells, natural killer cells, eosinophils, neutrophils, B cells, CD8⁺ T cells, and T_H1, T_H2, and T_H17 and regulatory T cells. Both direct and indirect activation of the stress axis promotes IL-10 secretion. IL-10 deregulation plays a role in the development of a large number of inflammatory diseases such as neuropathic pain, Parkinson's disease, Alzheimer's disease, osteoarthritis, rheumatoid arthritis, psoriasis, systemic lupus erythematosus, type 1 diabetes, inflammatory bowel disease, and allergy. Curcumin is a natural anti-inflammatory compound able to induce the expression and production of IL-10 and enhancing its action on a large number of tissues. In vitro and in pre-clinical models curcumin is able to modulate the disease pathophysiology of conditions such as pain and neurodegenerative diseases, bowel inflammation, and allergy, but also of infections and cancer through its effect on IL-10 secretion. In humans, at least one part of the positive effects of curcumin on health could be related to its ability to enhance IL-10 -mediated effects.

Effects of coenzyme Q10 supplementation on inflammatory markers: A systematic review and meta-analysis of randomized controlled trials

The aims of this meta-analysis were to evaluate the effects of coenzyme Q10 (CoQ10) supplementation on inflammatory mediators including C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) by analyzing published randomized controlled trials (RCTs). A systematic search in PubMed, Cochrane Library and Clinicaltrials.gov was performed to identify eligible RCTs. Data synthesis was performed using a random- or a fixed-effects model depending on the results of heterogeneity tests, and pooled data were displayed as weighed mean difference (WMD) and 95% confidence interval (CI). Seventeen RCTs were selected for the meta-analysis. CoQ10 supplementation significantly reduced the levels of circulating CRP (WMD: -0.35mg/L, 95% CI: -0.64 to -0.05, P=0.022), IL-6 (WMD: -1.61pg/mL, 95% CI: -2.64 to -0.58, P=0.002) and TNF-α (WMD: -0.49pg/mL, 95% CI: -0.93 to -0.06, P=0.027). The results of meta-regression showed that the changes of CRP were independent of baseline CRP, treatment duration, dosage, and patients characteristics. In the meta-regression analyses, a higher baseline IL-6 level was significantly associated with greater effects of CoQ10 on IL-6 levels (P for interaction=0.006). In conclusion, this meta-analysis of RCTs suggests significant lowering effects of CoQ10 on CRP, IL-6 and TNF-α. However, results should be interpreted with caution because of the evidence of heterogeneity and limited number of studies.

Aortic perivascular adipose-derived interleukin-6 contributes to arterial stiffness in low-density lipoprotein receptor deficient mice

We tested the hypothesis that aortic perivascular adipose tissue (PVAT) from young low-density lipoprotein receptor-deficient (LDLr(-/-)) mice promotes aortic stiffness and remodeling, which would be mediated by greater PVAT-derived IL-6 secretion. Arterial stiffness was assessed by aortic pulse wave velocity and with ex vivo intrinsic mechanical properties testing in young (4-6 mo old) wild-type (WT) and LDLr(-/-) chow-fed mice. Compared with WT mice, LDLr(-/-) mice had increased aortic pulse wave velocity (407 ± 18 vs. 353 ± 13 cm/s) and intrinsic mechanical stiffness (5,308 ± 623 vs. 3,355 ± 330 kPa) that was associated with greater aortic protein expression of collagen type I and advanced glycation end products (all P < 0.05 vs. WT mice). Aortic segments from LDLr(-/-) compared with WT mice cultured in the presence of PVAT had greater intrinsic mechanical stiffness (6,092 ± 480 vs. 3,710 ± 316 kPa), and this was reversed in LDLr(-/-) mouse arteries cultured without PVAT (3,473 ± 577 kPa, both P < 0.05). Collagen type I and advanced glycation end products were increased in LDLr(-/-) mouse arteries cultured with PVAT (P < 0.05 vs. WT mouse arteries), which was attenuated when arteries were cultured in the absence of PVAT (P < 0.05). PVAT from LDLr(-/-) mice secreted larger amounts of IL-6 (3.4 ± 0.1 vs. 2.3 ± 0.7 ng/ml, P < 0.05), and IL-6 neutralizing antibody decreased intrinsic mechanical stiffness in LDLr(-/-) aortic segments cultured with PVAT (P < 0.05). Collectively, these data provide evidence for a role of PVAT-derived IL-6 in the pathogenesis of aortic stiffness and remodeling in chow-fed LDLr(-/-) mice.

Interactions between C-reactive protein genotypes with markers of nutritional status in relation to inflammation

Inflammation, as indicated by C-reactive protein concentrations (CRP), is a risk factor for chronic diseases. Both genetic and environmental factors affect susceptibility to inflammation. As dietary interventions can influence inflammatory status, we hypothesized that dietary effects could be influenced by interactions with single nucleotide polymorphisms (SNPs) in the CRP gene. We determined 12 CRP SNPs, as well as various nutrition status markers in 2010 black South Africans and analyzed their effect on CRP. Interactions were observed for several genotypes with obesity in determining CRP. Lipid intake modulated the pro-inflammatory effects of some SNPs, i.e., an increase in both saturated fatty acid and monounsaturated fatty acid intake in those homozygous for the polymorphic allele at rs2808630 was associated with a larger increase in CRP. Those harboring the minor alleles at rs3093058 and rs3093062 presented with significantly higher CRP in the presence of increased triglyceride or cholesterol intake. When harboring the minor allele of these SNPs, a high omega-6 to -3 ratio was, however, found to be anti-inflammatory. Carbohydrate intake also modulated CRP SNPs, as HbA1C and fasting glucose levels interacted with some SNPs to influence the CRP. This investigation highlights the impact that nutritional status can have on reducing the inherent genetic susceptibility to a heightened systemic inflammatory state.

Unraveling the complex relationship triad between lipids, obesity, and inflammation

Obesity today stands at the intersection between inflammation and metabolic disorders causing an aberration of immune activity, and resulting in increased risk for diabetes, atherosclerosis, fatty liver, and pulmonary inflammation to name a few. Increases in mortality and morbidity in obesity related inflammation have initiated studies to explore different lipid mediated molecular pathways of attempting resolution that uncover newer therapeutic opportunities of anti-inflammatory components. Majorly the thromboxanes, prostaglandins, leukotrienes, lipoxins, and so forth form the group of lipid mediators influencing inflammation. Of special mention are the omega-6 and omega-3 fatty acids that regulate inflammatory mediators of interest in hepatocytes and adipocytes via the cyclooxygenase and lipoxygenase pathways. They also exhibit profound effects on eicosanoid production. The inflammatory cyclooxygenase pathway arising from arachidonic acid is a critical step in the progression of inflammatory responses. New oxygenated products of omega-3 metabolism, namely, resolvins and protectins, behave as endogenous mediators exhibiting powerful anti-inflammatory and immune-regulatory actions via the peroxisome proliferator-activated receptors (PPARs) and G protein coupled receptors (GPCRs). In this review we attempt to discuss the complex pathways and links between obesity and inflammation particularly in relation to different lipid mediators.

Modulation of circulating macrophage migration inhibitory factor in the elderly

Aging increases the risk for cardiovascular morbidity and mortality. Chronic low-grade inflammation deteriorates vascular function, increases age-related vascular stiffness, and affects hemodynamics. The proinflammatory cytokine macrophage migration inhibitory factor (MIF) is a major mediator of atherosclerosis. Plasma MIF levels are associated with arterial stiffness, a hallmark of vascular aging. Preclinical studies show that blockade of MIF leads to atherosclerotic plaque regression. Nutritional approaches provide opportunities to counteract age-related inflammation. Following a chronic dietary supplementation with the micronutrient nitrate has been demonstrated to improve vascular stiffness. Whether dietary nitrate affects circulating MIF levels is not known. In a randomized placebo-controlled, double-blinded study, elderly subjects received a dietary nitrate supplementation for 4 weeks. Dietary nitrate led to a decrease in plasma MIF levels in the elderly and to an improvement in vascular functions. This was associated with a reduction in central systolic blood pressure. Our data show that supplementation with dietary nitrate is associated with a reduction of circulating MIF levels along with an improvement in vascular function. This supports the concept of dietary approaches to modulate age-related changes of vascular functions.

Hypertension in obese type 2 diabetes patients is associated with increases in insulin resistance and IL-6 cytokine levels: potential targets for an efficient preventive intervention

Increased body weight as well as type 2 diabetes (T2D) are found to be associated with increased incidence of hypertension, although the mechanisms facilitating hypertension in T2D or nondiabetic individuals are not clear. Therefore, in this study we compared the levels of insulin resistance (IR:OGIS), plasma insulin (PI:RIA) levels, and pro-inflammatory cytokines (IL-6 and TNF-α: ELISA), being risk factors previously found to be associated with hypertension, in T2D patients showing increased body weight (obese and overweight, BMI ≥ 25 kg/m²) with hypertension (group A, N = 30), or without hypertension (group B, N = 30), and in nonobese (BMI < 25 kg/m²), normotensive controls (group C, N = 15). We found that OGIS index was the lowest (A: 267 ± 35.42 vs. B: 342.89 ± 32.0, p < 0.01) and PI levels were the highest (A: 31.05 ± 8.24 vs. B: 17.23 ± 3.23, p < 0.01) in group A. In addition, IL-6 levels were higher in group A (A: 15.46 ± 5.15 vs. B: 11.77 ± 6.09; p < 0.05) while there was no difference in TNF-α levels. Our results have shown that appearance of hypertension in T2D patients with increased body weight was dependent on further increase in IR which was associated with the rise in pro-inflammatory IL-6 cytokine. The results imply that lifestyle intervention aimed to decrease IR might be beneficial in reducing the risk for hypertension in those T2D individuals.

Does a diet high or low in fat influence the oxidation potential of VLDL, LDL and HDL subfractions?

BACKGROUND AND AIMS

High-fat diets have become increasingly popular for weight-loss, but their effect on the oxidation potential of lipoprotein subfractions has not been studied. Therefore, this study compared the effects of high-fat vs. low-fat weight reduction diets on this parameter.

METHODS AND RESULTS

Very-low, low- and high-density lipoprotein (VLDL, LDL & HDL) subfractions were isolated by rapid ultracentrifugation from 24-overweight/obese subjects randomised to a high- or low-fat diet. The lipoprotein subfractions were assessed for oxidation potential by measuring conjugated diene (CD) production and time at half maximum. We found a significant between-group difference in oxidation potential. Specifically, a high-fat diet led to increased CD production in VLDL(A-D) and HDL(2&3), and a prolongation of time at half maximum. Within-group differences found that CDs increased in VLDL(A&D), LDL(I-III) and HDL(2&3) in the high-fat group and fell in VLDL(A-C) and HDL(2&3) and increased in LDL(I&II), in the low-fat group. Furthermore, following both diets all lipoprotein subfractions, except LDL(II) in the low-fat group, were protected against oxidation.

CONCLUSION

These results demonstrate that at first glance, a high-fat diet may be indicative of having heart-protective properties. However, this may be erroneous, as although the time for oxidation to occur was prolonged, once this occurred these lipoproteins had the potential to produce significantly more oxidised substrate. Conversely, a low-fat diet may be considered anti-atherogenic, as these subfractions were protected against oxidation and mainly contained fewer oxidised substrate. Thus, increased fat intake may, by increasing the oxidation product within lipoprotein subfractions, increase cardiovascular disease.

Association of parathyroid hormone and 25-OH-vitamin D levels with arterial stiffness in postmenopausal women with vitamin D insufficiency

AIM

Vitamin D insufficiency and increased parathyroid hormone (PTH) levels have been suggested as prognostic indices for cardiovascular disease. Arterial stiffness, a surrogate marker for cardiovascular disease, is often increased in patients with primary hyperparathyroidism. PTH levels increase in patients with low 25-OH-vitamin D levels, but the influence of such an increase on arterial stiffness has not been investigated in postmenopausal women with reduced 25-OH-vitamin D levels. We therefore investigated the association between PTH and aortic stiffness in postmenopausal women with reduced 25-OH-vitamin D levels.

METHODS

One hundred fifty postmenopausal women with 25-OH-vitamin D insufficiency (<30 ng/mL) were recruited. Aortic pulse wave velocity (aPWV), a measure of arterial stiffness, PTH and 25-OH-vitamin D levels were measured. Cardiovascular risk factors and markers of bone formation were evaluated.

RESULTS

The 25-OH-vitamin D levels were associated with aPWV (rho=-0.23, p=0.006), but the association was not significant when controlling for PTH. Significant correlates of aPWV included age, body mass index, mean arterial pressure and PTH (rho=0.39, p<0.001). Arterial stiffness was predicted by logarithmically transformed PTH levels (β=0.23, p=0.007), independent of traditional cardiovascular risk factors and factors involved in bone formation. Increased PTH levels (>62 pg/mL) were associated with a 3.0-5.4-fold increased probability of having a mild-severe increase in aortic stiffness, irrespective of confounders.

CONCLUSION

Among postmenopausal women with reduced 25-OH-vitamin D levels, elevated PTH levels were a significant predictor of aortic stiffness, irrespective of cardiovascular risk factors and of factors involved in bone formation. PTH accounted for the association between 25-OH-vitamin D levels and aortic stiffness.

A review of the evidence for the effects of total dietary fat, saturated, monounsaturated and n-6 polyunsaturated fatty acids on vascular function, endothelial progenitor cells and microparticles

Vascular dysfunction is recognised as an integrative marker of CVD. While dietary strategies aimed at reducing CVD risk include reductions in the intake of SFA, there are currently no clear guidelines on what should replace SFA. The purpose of this review was to assess the evidence for the effects of total dietary fat and individual fatty acids (SFA, MUFA and n-6 PUFA) on vascular function, cellular microparticles and endothelial progenitor cells. Medline was systematically searched from 1966 until November 2010. A total of fifty-nine peer-reviewed publications (covering fifty-six studies), which included five epidemiological, eighteen dietary intervention and thirty-three test meal studies, were identified. The findings from the epidemiological studies were inconclusive. The limited data available from dietary intervention studies suggested a beneficial effect of low-fat diets on vascular reactivity, which was strongest when the comparator diet was high in SFA, with a modest improvement in measures of vascular reactivity when high-fat, MUFA-rich diets were compared with SFA-rich diets. There was consistent evidence from the test meal studies that high-fat meals have a detrimental effect on postprandial vascular function. However, the evidence for the comparative effects of test meals rich in MUFA or n-6 PUFA with SFA on postprandial vascular function was limited and inconclusive. The lack of studies with comparable within-study dietary fatty acid targets, a variety of different study designs and different methods for determining vascular function all confound any clear conclusions on the impact of dietary fat and individual fatty acids on vascular function.

The tsim tsoum approaches for prevention of cardiovascular disease

The Tsim Tsoum Concept means that humans evolved on a diet in which nature recommends to ingest fatty acids in a balanced ratio (polyunsaturated(P) : saturated(S) =w-6 : w-3 = 1 : 1)as part of dietary lipid pattern where monounsaturated fatty acids(MUFA) is the major fatty acid(P : M : S = 1 : 6 : 1) in the background of other dietary factors; antioxidants, vitamins, minerals and fiber as well as physical activity and low mental stress. Several hundred years ago, our diet included natural foods; fruits, vegetables, green vegetables, seeds, eggs and honey. Fish, and wild meat were also available to pre-agricultural humans which shaped modern human genetic nutritional requirement. Cereal grains (refined), and vegetable oils that are rich in w-6 fatty acids are relatively recent addition to the human diet that represent dramatic departure from those foods to which we are adapted. Excess of linoleic acid, trans fatty acids (TFA), saturated and total fat as well as refined starches and sugar are proinflammatory. Low dietary MUFA and n-3 fatty acids and other long chain polyunsarurated fatty acids (LCPUFA) are important in the pathogenesis of metabolic syndrome. Increased sympathetic activity with greater secretion of neurotransmitters in conjunction of underlying long chain PUFA deficiency, and excess of proinflammatory nutrients, may damage the neurons via proinflammatory cytokines, in the ventromedial hypothalamus and insulin receptors in the brain.Since, 30–50% of the fatty acids in the brain are LCPUFA, especially omega-3 fatty acids, which are incorporated in the cell membrane phospholipids, it is possible that their supplementation may be protective.Blood lipid composition does reflect one's health status: (a) circulating serum lipoproteins and their ratio provide information on their atherogenicity to blood vessels and (b) circulating plasma fatty acids, such as w-6/w-3 fatty acid ratio, give indication on proinflammatory status of blood vessels, cardiomyocytes, liver cells and neurones; (a) and (b) are phenotype-related and depend on genetic, environmental and developmental factors. As such, they appear as universal markers for holistic health and these may be important in the pathogenesis of cardiovascular diseases and cancer, which is the main consideration of Tsim Tsoum concept.

An analysis of prospective risk factors for aortic stiffness in men: 20-year follow-up from the Caerphilly prospective study

Arterial stiffness is an important determinant of cardiovascular risk. The precise risk factors for arterial stiffening remain unclear. We aimed to identify potential risk factors using prospective exposure data from the Caerphilly Prospective Study. Aortic pulse wave velocity and augmentation index were measured in 825 men and related to current (2004) and baseline (1979-1988) anthropometric, hemodynamic, and biochemical factors. The mean age of the men was 74 years, with an average follow-up of 20 years. The only independent baseline predictors of current velocity were pulse pressure (standardized beta-coefficient: 0.58), C-reactive protein (0.35), glucose (0.25), and waist circumference (0.23). The sole baseline predictor of current augmentation index was fibrinogen (0.78). After additional adjustment for the corresponding current risk factor, pulse wave velocity was best related to cumulative exposure to C-reactive protein, whereas augmentation index was most strongly related to current levels. Velocity was also more strongly correlated with baseline levels of triglycerides and smoking but with current waist circumference. The pulse pressure heart rate product assessed over the whole of 20 years was independently correlated with aortic pulse wave velocity but not augmentation index. Other than blood pressure, established cardiovascular risk factors have only a modest effect on aortic stiffness and wave reflection. Inflammation and the level of repetitive cyclic stress are important predictors of aortic stiffness, whereas wave reflection is predicted by acute inflammation only. Adequate control of pulse pressure and heart rate, as well as reducing inflammation, may, in the long-term, retard aortic stiffening, although this remains to be tested directly.

Effect of diet on the low-grade and chronic inflammation associated with obesity and metabolic syndrome

Adipose tissue is an active endocrine and paracrine organ that releases a large number of cytokines and biomarkers, which are involved in the development of chronic diseases. These effects have been attributed to direct or indirect mechanisms acting on insulin resistance, inflammation and endothelial dysfunction. In addition, the expression and secretion of these biomarkers in various tissues can be influenced by dietary patterns, with an effect on inflammatory status. In this context, following an energy-balanced diet, moderate in carbohydrates, high in oleic and omega-3 fatty acids, and low in saturated and trans fatty acids, with high intake of fruits and legumes and moderate alcohol consumption, appears to have beneficial effects on the inflammatory state associated with obesity and the manifestations of metabolic syndrome. However, the long-term impact of habitual intake and the mechanisms involved in distinct physiological and pathological conditions remain unclear.

Impact of genetic and environmental factors on hsCRP concentrations and response to therapeutic agents

BACKGROUND

Inflammation plays an instrumental role in all stages of atherosclerosis. High-sensitivity C-reactive protein (hsCRP), a systemic inflammatory marker, has been gaining recognition as an independent risk factor for cardiovascular disease (CVD). Both baseline hsCRP concentrations and drug-induced hsCRP changes are highly variable and potentially subject to genetic regulation.

CONTENT

This review summarizes the current studies examining the effect of genetic and environmental factors on baseline plasma hsCRP concentrations, with a main focus on C-reactive protein, pentraxin-related (CRP) genetic polymorphisms and various dietary components that affect hsCRP concentrations. We also address the association of CRP genetic variations with CVD risk, a relationship that may support or refute the causality of CRP in the atherosclerotic process. Moreover, we discuss the impact of CRP genetic polymorphisms on hsCRP changes in response to 3-week fenofibrate treatment in the genetic intervention of the Genetics of Lipid Lowering Drugs and Diet Network study.

SUMMARY

Genetic variants on the CRP locus and other loci and dietary and lifestyle factors are responsible for the interindividual variability of plasma hsCRP concentrations. CRP genetic variants further influence differing plasma hsCRP response after 3-week fenofibrate treatment in patients with metabolic syndrome. Future studies focusing on the influence and interaction of genetic variation on the hsCRP response to dietary and other behavior modification as well as drug treatment could have important implications for the development of more personalized preventive and therapeutic approaches to reduce CVD.

Microparticles derived from endothelial progenitor cells in patients at different cardiovascular risk

OBJECTIVES

Exposure to cardiovascular risk factors causes the release of pro-atherogenic microparticles from vascular cells and reduces the number of the atheroprotective endothelial progenitor cells (EPCs). We investigated whether microparticles shedding from EPCs are detectable in cultures of EPCs and in the circulation of subjects with various degrees of cardiovascular risk. We also investigated the relationship of EPCs-derived microparticles to cardiovascular risk factors and aortic stiffness, a marker of cardiovascular risk and impaired vascular repair by EPCs.

METHODS AND RESULTS

We estimated the 10-year Framingham risk score in 105 individuals with various degrees of cardiovascular risk and measured the number of circulating EPCs, EPCs-derived microparticles (CD34+/KDR+) and aortic stiffness. Release of CD34+/KDR+ microparticles was tested in cultures of EPCs exposed to hydrogen-peroxide. CD34+/KDR+ microparticles were found in EPCs cultures incubated with hydrogen-peroxide. Framingham risk was associated with EPCs (r=-0.47, p<0.001) and CD34+/KDR+ microparticles (r=0.56, p<0.001). Low EPCs (r=-0.59, p<0.001) and high CD34+/KDR+ microparticle (r=0.57, p<0.001) levels were predictors of aortic stiffness, independent of the Framingham risk.

CONCLUSIONS

EPCs undergo fragmentation into microparticles when exposed to a pro-apoptotic milieu. Increased microparticle shedding from EPCs may reduce circulating EPCs levels and may thus contribute to increase aortic stiffness beside traditional risk factors.

Effects of rosuvastatin on 3-nitrotyrosine and aortic stiffness in hypercholesterolemia

BACKGROUND AND AIMS

Early atherosclerosis is characterized by reduced large artery distensibility, paralleled by an increased peroxynitrite formation and nitration of tyrosine in proteins. The aim of the present study was to investigate the short-term effect of cholesterol lowering with rosuvastatin on 3-nitrotyrosine (3-NT), a marker of peroxynitrite-mediated oxidative stress, and on arterial stiffness.

METHODS AND RESULTS

71 outpatients with primary hypercholesterolemia were recruited for this randomized open-label intervention study; 35 patients were assigned to 4-week rosuvastatin therapy (10mg daily) with a low-fat diet, and 36 patients to a low-fat diet only. Within the cohort of 71 hypercholesterolemic patients, there was a significant correlation between cholesterol levels, 3-NT and aortic pulse wave velocity (aPWV), that is a reliable measure of aortic stiffness. Among those patients who received rosuvastatin, significant reductions in plasma cholesterol, 3-NT and aPWV were observed. Reductions in both aPWV and 3-NT levels correlated significantly with the decrease in plasma cholesterol. Reduction of plasma cholesterol was the only independent predictor for reduced arterial stiffness following rosuvastatin therapy.

CONCLUSION

Cholesterol reduction achieved following short-term rosuvastatin therapy is associated with a decrease in peroxynitrite-mediated oxidative stress and an improvement in large artery distensibility; reduction in arterial stiffness is directly attributable to rosuvastatin-induced cholesterol lowering and not to reduction of plasma 3-NT levels.

Increased Ratio of CD31 + /CD42 − Microparticles to Endothelial Progenitors as a Novel Marker of Atherosclerosis in Hypercholesterolemia

Objectives— Atherosclerosis may be caused by increased endothelial damage and by a consumptive loss of endothelial repair capacity by endothelial progenitors. Arterial stiffness is a reliable marker of atherosclerosis and a positive correlate of endothelial damage. We investigated whether an increased ratio of CD31 + /CD42 − microparticles to endothelial progenitors, a possible indicator of endothelial damage and impaired endothelium reparation, may contribute to aortic stiffness in hypercholesterolemia. We also studied the in vitro effect of microparticles from hypercholesterolemic patients on endothelial progenitor survival.

Methods and Results— Circulating CD31 + /CD42 − microparticles, endothelial progenitors, and aortic pulse wave velocity (aPWV), a measure of aortic stiffness, were measured in 50 patients with never-treated hypercholesterolemia and 50 normocholesterolemic controls. Hypercholesterolemic patients had more circulating CD31 + /CD42 − microparticles, less endothelial progenitors, and a stiffer aorta than controls. aPWV was associated with CD31 + /CD42 − microparticles ( r =0.61; P <0.001), endothelial progenitors ( r =−0.45, P <0.001), and with cholesterol levels ( r =0.51; P <0.001). High plasma cholesterol and a high ratio of CD31 + /CD42 − microparticles to endothelial progenitors independently predicted an increased aPWV. Microparticles from hypercholesterolemic patients caused a significant endothelial progenitor loss in vitro.

Conclusions— Hypercholesterolemia-related aortic stiffness is promoted by plasma cholesterol directly, increased endothelial damage, and reduced endothelium repair capacity by endothelial progenitors.

The effects of diet on inflammation: emphasis on the metabolic syndrome

Reducing the incidence of coronary heart disease with diet is possible. The main dietary strategies include adequate omega-3 fatty acids intake, reduction of saturated and trans-fats, and consumption of a diet high in fruits, vegetables, nuts, and whole grains and low in refined grains. Each of these strategies may be associated with lower generation of inflammation. This review examines the epidemiologic and clinical evidence concerning diet and inflammation. Dietary patterns high in refined starches, sugar, and saturated and trans-fatty acids, poor in natural antioxidants and fiber from fruits, vegetables, and whole grains, and poor in omega-3 fatty acids may cause an activation of the innate immune system, most likely by an excessive production of proinflammatory cytokines associated with a reduced production of anti-inflammatory cytokines. The whole diet approach seems particularly promising to reduce the inflammation associated with the metabolic syndrome. The choice of healthy sources of carbohydrate, fat, and protein, associated with regular physical activity and avoidance of smoking, is critical to fighting the war against chronic disease. Western dietary patterns warm up inflammation, while prudent dietary patterns cool it down.

Dietary Factors That Promote or Retard Inflammation

Inflammation plays a pivotal role in all stages of atherosclerosis. Cardiovascular risk factors and metabolic syndrome are typified by low-grade inflammation. Intervention trials convincingly demonstrate that weight loss reduces biomarkers of inflammation, such as C-reactive protein (CRP) and interleukin (IL)-6. Limited studies have shown that certain dietary factors; oleic acid, alpha-linolenic acid, and antioxidants RRR-alpha-alpha tocopherol, reduce biomarkers of inflammation. Most of the studies with fish oil supplementation have shown null effects, and conflicting results have been reported with saturated and trans fatty acids, cholesterol, and soy intake. Much further research is needed to define the role of individual dietary factors on the biomarkers of inflammation and the mechanism of the anti-inflammatory effects of weight loss.

The effect of chronic consumption of red wine polyphenols on vascular function in postmenopausal women

OBJECTIVE

To elucidate whether the chronic consumption of dealcoholised red wine (DRW) (polyphenol-rich component) and/or red wine (RW) improves vascular function in hypercholesterolaemic postmenopausal women.

DESIGN, SUBJECTS AND INTERVENTION

A randomised parallel-arm study. Forty-five hypercholesterolaemic postmenopausal women were randomised into either water, DRW or RW group for 6 weeks following a 4 week washout. Fasting measures of central haemodynamic parameters, arterial wave reflection and endothelial nitric oxide were taken at 0 and 6 weeks.

SETTING

Clinic in the School of Public Health, Curtin University.

RESULTS

There were no significant between group differences in arterial stiffness as measured by augmentation index (AIx) and augmentation pressure (AP). However, a significant within group decrease in AIx (-9%, P=0.02) and AP (-12%, P=0.02) was observed following DRW consumption. No significant changes were observed in central haemodynamic parameters and endothelial nitric oxide levels following DRW and RW consumption, compared to water.

CONCLUSIONS

Neither the chronic consumption of DRW nor RW improved markers of arterial stiffness, compared to control. However, the significant within group improvements in these indices following the consumption of DRW cannot be overlooked and warrant further investigation.

Diet and inflammation: a link to metabolic and cardiovascular diseases

Both epidemiological studies and intervention trials support an important role of diet in reducing the risk of a variety of chronic diseases, including cardiovascular disease, and overall mortality. We discuss available evidence indicating that the generation of a pro-inflammatory milieu might be one mechanism through which unhealthy diets are linked to metabolic and cardiovascular diseases. In practical terms, fully understanding the link between diet and inflammation holds the premise to elucidate the mechanisms by which dietary patterns improve cardiovascular health.