Serum markers of vascular inflammation in dyslipemia

Relationship Between Serum Endocan Levels and Other Predictors of Endothelial Dysfunction in Obese Women

Endocan, or endothelial cell-specific molecule-1 (ESM-1), is a potential inflammatory marker implicated in endothelial dysfunction. The purpose of this study was to determine the correlation between serum endocan levels and the presence and severity of endothelial dysfunction, and the relationships with serum intracellular adhesion molecule-1 (ICAM-1), adiponectin (a marker of inflammation), high sensitivity C-reactive protein (hsCRP) levels, and carotid intima-media thickness (cIMT) in obese subjects. Serum endocan, ICAM-1, adiponectin, hsCRP levels, and cIMT were evaluated in 76 obese women (BMI > 30 kg/m2) and 53 controls (BMI < 25 kg/m2). ICAM-1 (P = .01), hs-CRP (p < 0.001), and cIMT (p < .001) were significantly higher, while adiponectin (P = .006) was significantly lower, in obese women compared with the controls. Serum endocan levels were similar between the obese (470.5 ± 171.3 pg/mL) and controls (471.9 ± 146.3 pg/mL) (P = .732). There was no correlation between serum endocan values and the endothelial dysfunction markers, hsCRP (r = -.021), ICAM-1 (r = -.054), adiponectin (r = .113), or cIMT (r = -.060) in obesity. Endocan is not a suitable marker of endothelial dysfunction in the context of obesity. More research is required to evaluate the role of endocan in the regulation of inflammatory processes in obesity.

Inflammatory Biomarkers and Components of Metabolic Syndrome in Adolescents: a Systematic Review

Metabolic syndrome (MetS) has been prevalent among adolescents. The association between the concentration of inflammatory markers and the individual components of the metabolic syndrome indicates that inflammation, when there is no recent or ongoing disease, mediated by an inflammatory process, is an event that may precede the development of metabolic disorders in teenagers. The objective of this study is to verify the association of inflammatory biomarkers with the components of metabolic syndrome in adolescents. From a search of 3 databases, 13 articles met the study inclusion criteria. Two investigators independently extracted data from included studies. The evaluated inflammatory biomarkers are related to the components of MetS (insulin resistance, central and visceral obesity, arterial hypertension, dyslipidemia), which may increase the risk of developing the syndrome in adolescents. The results of this review are of clinical relevance, since the evaluation of inflammatory biomarkers in the presence of metabolic alterations can help to identify the risk factors that lead to the progression of MetS in adolescents.

Effects of chronic apical periodontitis on the inflammatory response of the aorta in hyperlipemic rats

OBJECTIVES

To study the effects of chronic apical periodontitis (CAP) on the inflammatory response and initial lesion of aorta in hyperlipemic rats.

MATERIALS AND METHODS

Sprague-Dawley (SD) rats aged 14 weeks were randomly divided into 4 experimental groups (n = 8), namely, normal diet (ND), high-fat diet (HFD), CAP, and HFD + CAP. The rats were raised under controlled conditions and fed with diet specified for each group. All subjects were euthanatized after 14 weeks for histopathological analysis. Serum cytokines were analyzed to assess changes in gene and protein expression of aorta via enzyme-linked immunosorbent assay and real-time polymerase chain reaction. Results were analyzed by one-way ANOVA.

RESULTS

Low-density lipoprotein cholesterol levels in rats in HFD + CAP group were significantly higher than those in other groups. By comparison, low-density lipoprotein cholesterol levels in rats in both the HFD and HFD + CAP groups were significantly lower than those in the other groups. No significant difference among all groups was observed in terms of CRP level. However, levels of IL-2, IL-6, and IL-10 increased in the experimental CAP rats compared with the control rats. mRNA expression levels of MCP-1, TLR-4, and NF-κB p65 were markedly elevated in rats in the HFD group compared with those in rats in the ND group. TLR-4 mRNA expression was significantly higher in rats in the HFD + CAP group than that in rats in the HFD group.

CONCLUSIONS

CAP mediated the high expression of cytokines and induced the initial inflammatory response in the aorta. Apical periodontitis may affect the level of inflammatory cytokines (IL-2, IL-6, and IL-10) depending on the immune response.

CLINICAL RELEVANCE

CAP may trigger a systemic inflammatory response and affect the aorta of patients.

Effects of statins and exercise on postprandial lipoproteins in metabolic syndrome vs metabolically healthy individuals

AIMS

To determine if the combination of exercise and statin could normalize postprandial triglyceridaemia (PPTG) in hypercholesteraemic individuals.

METHODS

Eight hypercholesteraemic (blood cholesterol 182 ± 38 mg dL^-1 ; low-density lipoprotein-cholesterol [LDL-c] 102 ± 32 mg dL^-1 ) overweight (body mass index 30 ± 4 kg m^-2 ) individuals with metabolic syndrome (MetS) were compared to a group of 8 metabolically healthy (MetH) controls (blood cholesterol 149 ± 23 mg dL^-1 ; LDL-c 77 ± 23 mg dL^-1 , and body mass index 23 ± 2 kg m^-2 ). Each group underwent 2 PPTG tests, either 14 hours after a bout of intense exercise or without previous exercise. Additionally, MetS individuals were tested 96 hours after withdrawal of their habitual statin medication to study medication effects.

RESULTS

A bout of exercise before the test meal did not reduce PPTG in MetS (P = .347), but reduced PPTG by 46% in MetH (413 ± 267 to 224 ± 142 mg dL^-1 for 5 h incremental area under the curve; P = .02). In both trials (i.e., either after a bout of intense exercise or without previous exercise), statin withdrawal in MetS greatly increased PPTG (average 65%; P < .01), mean LDL-c (average 25%; P < .01), total cholesterol (average 16%; P < .01) and apolipoprotein (Apo) B48 (24%; P < .01), without interference from exercise. However, Apo B100 was not affected by statin withdrawal.

CONCLUSION

Hypercholesteraemic MetS individuals (compared to MetH controls) fail to show an effect of exercise on reducing PPTG. However, chronic statin medication blunts the elevations in triglyceride after a fat meal (i.e., incremental area under the curve of PPTG) reducing their cardiovascular risk associated with their atherogenic dyslipidaemia. Statin decreases PPTG by reducing the secretion or accelerating the catabolism of intestinal Apo B48.

Increased cytokines production and oxidative stress are related with purinergic signaling and cell survival in post-thyroidectomy hypothyroidism

Thyroid hormones have essential roles in regulation of cellular functions, including the immune system. The purinergic signaling, activated through extracellular nucleotides and nucleosides has also strong implications in immune response regulation. Hypothyroidism may involve effects on the immune and purinergic systems. In view of that, we evaluated cytokines levels, their relation with the expression of purinergic enzymes and the effects of this condition on immune system cells from patients with post-thyroidectomy hypothyroidism. Increased IL6, IL10, IL17 and TNF-α levels as well as an increase in CD73 expression in lymphocytes were observed in patients' blood. Moreover, augmented myeloperoxidase activity, lipid peroxidation and thiolgroup production were observed in post-thyroidectomy hypothyroidism. In addition, proliferation and cell death of lymphocytes were enhanced when exposed to patients' serum. This study demonstrates that hypothyroidism is related to changes in the purinergic system, increased cytokines production and oxidative stress, which interfere in the cell life and signaling.

The co-existence of elevated high sensitivity C-reactive protein and homocysteine levels is associated with increased risk of metabolic syndrome: A 6-year follow-up study

Accumulating evidence has revealed that both high sensitivity C-reactive protein (hsCRP) and homocysteine (HCY) are associated with increased risk of metabolic syndrome (MetS) and cardiovascular disease. However, it is unclear whether the coexistence of these conditions accelerates the risk of metabolic syndrome (MetS). We hypothesized that the combination of high sensitivity C-reactive protein (hsCRP) and homocysteine (HCY) levels could exacerbate the development of MetS in a large prospective cohort study. We selected data from 3,170 individuals (1,614 men and 1,556 women) who participated in the Korean Genome and Epidemiology Study. Participants with high hsCRP and HCY levels were categorized into quartiles. MetS was defined based on the criteria of the modified National Cholesterol Education Program, Adult Treatment Panel III. The prevalence of MetS was higher in participants with concurrent high hsCRP and HCY compared to those with low hsCRP and HCY levels. The incidence of MetS at the 6-year follow-up was the highest in participants with concomitant high hsCRP and HCY levels, regardless of obesity. Even after adjusting for potential confounding factors including body mass index in a multivariate logistic regression model, subjects with elevated hsCRP and HCY levels had a 2.50-fold increased risk of developing MetS at the six-year follow-up compared to those who did not have high hsCRP and HCY level. MetS is more prevalent in the concurrent presence of elevated hsCRP and HCY levels. The combination of the two conditions may contribute to an increased risk of MetS, but these factors may not be synergistic.

Effect of mate tea (Ilex paraguariensis) on the expression of the leukocyte NADPH oxidase subunit p47phox and on circulating inflammatory cytokines in healthy men: a pilot study

Increased superoxide production by phagocytic NADPH oxidase has been associated with inflammatory conditions. Growing evidences suggest that dietary polyphenols may modulate the expression of NADPH oxidase subunits. Herein, we examined whether soluble mate tea (SMT) consumption - a polyphenol-rich beverage - affects the expression of the leukocyte NADPH oxidase protein p47^phox and/or circulating biomarkers of inflammation and antioxidant biomarkers in humans. In a two-phase study, nine men were requested to drink water (control) for 8 d and then follow a second 8-d period drinking SMT. Blood samples were analysed for p47^phox protein in CD16⁺/CD14^- cells, interleukin (IL)-1β (IL-1β), tumour necrosis factor-alpha (TNF-α), IL-6, total phenols, and reduced and oxidised glutathione (GSH and GSSG, respectively) after each study phase. After SMT intake, CD16⁺/CD14^- cells' p47^phox protein and serum TNF-α and IL-6 levels were significantly attenuated (P < .05) while plasma phenolic compounds and blood GSH:GSSG ratio were significantly enhanced (P < .05). Consumption of SMT favourably affected leukocytes' p47^phox expression and inflammatory cytokine and antioxidants levels in peripheral blood, which may help decrease oxidative stress and low-grade inflammation.

Serum Klotho (but not haplotypes) associate with the post-myocardial infarction status of older adults

OBJECTIVES:

The number of deaths from vascular diseases is incredibly high worldwide, and reliable markers for major events are still needed. The current cross-sectional study investigated the association of Klotho haplotypes and Klotho serum levels with classic risk factors and a clinical history of vascular events.

METHODS:

Clinical, anthropometric, biochemical and nutritional assessments were conducted with 168 older adults, complemented by genotyping (rs9536314 and rs9527025) and the detection of serum Klotho (ELISA).

RESULTS:

Klotho levels and haplotypes did not associate with most classic risk factors for vascular events, including markers such as C-reactive protein and homocysteine. A positive association was only found between Klotho levels and the previous occurrence of a myocardial infarction by both correlational (p=0.006) and variance analyses (p<0.001), and these associations were independent of the context.

CONCLUSION:

Our results suggest that serum Klotho is higher in individuals with a clinical history of myocardial infarction but not with a history of coronary artery disease or stroke. None of the Klotho haplotypes were associated with the variables investigated herein.

Plasma amylin concentration in suckling goat neonates and its relationship with C-reactive protein, selected biochemical and hormonal indicators

Amylin is a recently discovered neuropeptide hormone that belongs to the calcitonin gene-related peptide family. It is co-secreted with insulin in response to feed intake. In goat kids, neonatal mortality and morbidity seems to be relatively higher than in other farm species. This high mortality and morbidity in goat kids may be associated with underdeveloped metabolism and immune system during the first week of life. The main objectives of this study were to determine amylin concentration and its relationship with some hormones, biochemical indicators and with a general inflammatory marker, CRP (C-reactive protein) in goat neonates. Blood samples were collected from 30 Saanen goat neonates at 20–35 days of age. Plasma amylin and other hormone concentrations were measured by ELISA, whereas serum biochemical indices were analysed by spectrophotometry. The mean values of plasma amylin concentrations were 9.07 ± 0.25 pmol/l. Plasma amylin concentrations were positively correlated with plasma non-esterified fatty acids, CRP, prolactin, cortisol, insulin; however, a negative correlation was determined between plasma amylin and serum triglyceride concentrations. The current study suggests that amylin contents are strongly associated with circulating concentrations of some hormones and with those of CRP in Saanen goat kids.

Does the sympathetic nervous system contribute to the pathophysiology of metabolic syndrome?

The metabolic syndrome (MS), formally known as syndrome X, is a clustering of several risk factors such as obesity, hypertension, insulin resistance, and dislypidemia which could lead to the development of diabetes and cardiovascular diseases (CVD). The frequent changes in the definition and diagnostic criteria of MS are indications of the controversy and the challenges surrounding the understanding of this syndrome among researchers. Obesity and insulin resistance are leading risk factors of MS. Moreover, obesity and hypertension are closely associated to the increase and aggravation of oxidative stress. The recommended treatment of MS frequently involves change of lifestyles to prevent weight gain. MS is not only an important screening tool for the identification of individuals at high risk of CVD and diabetes but also an indicator of suitable treatment. As sympathetic disturbances and oxidative stress are often associated with obesity and hypertension, the present review summarizes the role of sympathetic nervous system and oxidative stress in the MS.

Association between hypertriglyceridemia and protein oxidation and proinflammatory markers in normocholesterolemic and hypercholesterolemic individuals

BACKGROUND

Although hypercholesterolemia is a well-established risk factor for coronary heart disease, evidence suggests that increased triglyceride (TG) concentrations are also an independent risk factor. TG concentrations >150mg/dl are observed nearly twice as often in subjects with atherosclerosis. We assessed the association between hypertriglyceridemia and protein oxidation and proinflammatory markers in normocholesterolemic and hypercholesterolemic individuals.

METHODS

We included 127 volunteers enrolled in Cruz Alta, RS, Brazil. The patients were stratified based on total cholesterol and TG concentrations for analysis of associations with inflammation (high-sensitivity C-reactive protein - hs-CRP), endothelial dysfunction (nitric oxide - NOx) and oxidative stress (advanced oxidation protein products - AOPPs; ischemia-modified albumin - IMA). Correlations between variables were determined and multiple regression analysis was employed to investigate whether some variables correlate with TG concentrations.

RESULTS

Hypertriglyceridemia was related to oxidative stress and proinflammatory markers in individuals independent of total cholesterol concentrations. Moreover, the results indicate a stronger association of tested biomarkers with TG concentrations than with total cholesterol. The results indicate a positive correlation between oxidative stress and TG concentrations in the sera of hypercholesterolemia subjects. AOPPs and IMA concentrations were associated with the presence of hypertriglyceridemia in a manner that was independent of age, gender, hypertension and diabetes mellitus disease, smoking habits, sedentary lifestyle, BMI, waist circumference, LDL, HDL and total cholesterol concentrations.

CONCLUSIONS

We speculate that TG concentrations can reflect the enhancement of protein oxidation and proinflammation.

Obesity, inflammation, and insulin resistance

White adipose tissue (WAT) is considered an endocrine organ. When present in excess, WAT can influence metabolism via biologically active molecules. Following unregulated production of such molecules, adipose tissue dysfunction results, contributing to complications associated with obesity. Previous studies have implicated pro- and anti-inflammatory substances in the regulation of inflammatory response and in the development of insulin resistance. In obese individuals, pro-inflammatory molecules produced by adipose tissue contribute to the development of insulin resistance and increased risk of cardiovascular disease. On the other hand, the molecules with anti-inflammatory action, that have been associated with the improvement of insulin sensitivity, have your decreased production. Imbalance of these substances contributes significantly to metabolic disorders found in obese individuals. The current review aims to provide updated information regarding the activity of biomolecules produced by WAT.

Niacin inhibits vascular inflammation via downregulating nuclear transcription factor-κB signaling pathway

The study aimed to investigate the effect of niacin on vascular inflammatory lesions in vivo and in vitro as well as its lipid-regulating mechanism. In vivo study revealed that niacin downregulated the levels of inflammatory factors (IL-6 and TNF-α) in plasma, suppressed protein expression of CD68 and NF-κB p65 in arterial wall, and attenuated oxidative stress in guinea pigs that have been fed high fat diet. In vitro study further confirmed that niacin decreased the secretion of IL-6 and TNF-α and inhibited NF-κB p65 and notch1 protein expression in oxLDL-stimulated HUVECs and THP-1 macrophages. Moreover, niacin attenuated oxLDL-induced apoptosis of HUVECs as well. In addition, niacin significantly lessened lipid deposition in arterial wall, increased HDL-C and apoA levels and decreased TG and non-HDL-C levels in plasma, and upregulated the mRNA amount of cholesterol 7α-hydroxylase A1 in liver of guinea pigs. These data suggest for the first time that niacin inhibits vascular inflammation in vivo and in vitro via downregulating NF-κB signaling pathway. Furthermore, niacin also modulates plasma lipid by upregulating the expression of factors involved in the process of reverse cholesterol transport.

Affinity-recognition-based polymeric cryogels for protein depletion studies

Supermacroporous cryogels can be used for the depletion of highly abundant proteins prior to proteome investigations.

Monitoring immune modulation by nutrition in the general population: identifying and substantiating effects on human health

Optimal functioning of the immune system is crucial to human health, and nutrition is one of the major exogenous factors modulating different aspects of immune function. Currently, no single marker is available to predict the effect of a dietary intervention on different aspects of immune function. To provide further guidance on the assessment and interpretation of the modulation of immune functions due to nutrition in the general population, International Life Sciences Institute Europe commissioned a group of experts from academia, government and the food industry to prepare a guidance document. A draft of this paper was refined at a workshop involving additional experts. First, the expert group defined criteria to evaluate the usefulness of immune function markers. Over seventy-five markers were scored within the context of three distinct immune system functions: defence against pathogens; avoidance or mitigation of allergy; control of low-grade (metabolic) inflammation. The most useful markers were subsequently classified depending on whether they by themselves signify clinical relevance and/or involvement of immune function. Next, five theoretical scenarios were drafted describing potential changes in the values of markers compared with a relevant reference range. Finally, all elements were combined, providing a framework to aid the design and interpretation of studies assessing the effects of nutrition on immune function. This stepwise approach offers a clear rationale for selecting markers for future trials and provides a framework for the interpretation of outcomes. A similar stepwise approach may also be useful to rationalise the selection and interpretation of markers for other physiological processes critical to the maintenance of health and well-being.

Efeitos antioxidantes do selênio e seu elo com a inflamação e síndrome metabólica

O estado inflamatório crônico e de baixo grau bem como o estresse oxidativo associados à síndrome metabólica são fatores de risco relevantes para o desenvolvimento de doenças cardiovasculares. Neste contexto, o selênio é um mineral essencial que se encontra associado com o correto funcionamento dos principais processos metabólicos celulares. Estudos in vitro e in vivo em modelos experimentais de síndrome metabólica, bem como em humanos, tem investigado o efeito do selênio sobre a expressão e secreção de biomarcadores de inflamação e de estresse oxidativo. Para obtenção dos artigos sobre efeitos antioxidantes do selênio foram feitas pesquisas nos websites científicos. Na literatura encontramos numerosos artigos sobre os diferentes parâmetros modulados pelas concentrações plasmáticas de selênio, incluindo a proteína-C reativa, a interleucina-6, o fator de necrose tumoral-α, a interleucina-1β e a proteína transportadora de retinol-4. Esta revisão teve por objetivo discutir o papel do selênio nos processos inflamatórios e de estresse oxidativo, associados à síndrome metabólica.

C-reactive protein and lipid profiles in Korean patients with normal tension glaucoma

Purpose

To compare high-sensitivity C-reactive protein (hsCRP) levels and lipid profiles between Korean normal tension glaucoma (NTG) patients and healthy controls.

Methods

This cross-sectional study included 38 Korean patients with NTG and 38 age- and sex-matched healthy control subjects. We excluded the patients with cardiovascular risk factors and other systemic diseases that might affect CRP levels and lipid profiles. Each patient underwent a Humphrey visual field examination and blood sampling for hsCRP and lipid profile analyses. Subsequently, the NTG patients were classified into two groups based on their untreated intraocular pressure (IOP) level: low NTG (LNTG) with IOP≤13 mmHg (13 subjects) and high NTG (HNTG) with relatively high IOP (>13 and ≤21 mmHg, 25 subjects). The hsCRP levels and lipid profiles were compared between NTG patients and healthy controls, and between LNTG, HNTG, and healthy controls.

Results

There were no significant differences in hsCRP and lipid profiles between either the NTG patients and healthy controls, or between the LNTG, HNTG, and controls (p>0.05) after exclusion of Korean patients with cardiovascular risk factors. There was no significant association between hsCRP and visual field indices (p>0.05).

Conclusions

High-sensitivity C-reactive protein-related vascular inflammatory conditions may not be directly associated with the development of NTG, regardless of the untreated IOP level.

[Inflammation biomarkers capacity in predicting the metabolic syndrome]

The inflammatory process is the link between metabolic syndrome and cardiovascular diseases. To measure the degree of subclinical inflammation some inflammatory biomarkers have been considered. This work reviews the recent researches of the associations between inflammatory biomarkers and metabolic syndrome, as well as the capacity in predicting the metabolic syndrome. These biomarkers include pro-inflammatory cytokines, anti-inflammatory cytokines, adipokines, chemokines, inflammation markers derived from hepatocites, the consequence markers of inflammation and enzymes. This review integrates the new knowledge of inflammatory mediators interactions with metabolic syndrome, since these biomarkers play different roles and follow diverse metabolic ways.

Evaluation of ischemia-modified albumin in myocardial infarction and prostatic diseases

BACKGROUND

Ischemia-modified albumin (IMA) has been shown to be a rapidly rising and sensitive biochemical marker for the diagnosis of myocardial ischemia. In this study, we evaluated the levels of IMA in myocardial infarction and prostate diseases, as well as the influence of HDL cholesterol levels on C-reactive protein (CRP) and IMA levels.

METHODS

A total of 27 patients with myocardial infarction (MI), 102 patients with benign prostatic hyperplasia (BPH), 84 patients with prostate cancer (PCA), and 21 healthy subjects were enrolled in this study. IMA levels were measured in whole studied patients. Cardiac troponin I (cTnI), cholesterol, HDL cholesterol, and CRP were measured in MI and control groups.

RESULTS

IMA values were significantly higher in patients with MI (0.5215+/-0.0241 ABSU) and BPH (0.4150+/-0.0156 ABSU) in comparison to control subjects (0.3381+/-0.0194 ABSU). IMA and CRP were higher in MI group, especially in patients with HDL cholesterol levels lower than 38 mg/dL. The ability of IMA to discriminate myocardial infarction was higher than CRP. Significant correlations between CRP and HDL, CRP and IMA, and HDL and IMA were reported.

CONCLUSIONS

IMA and CRP increase in myocardial damage, and the decrease of HDL cholesterol appears to enhance the inflammatory response. IMA also increase in benign prostate hyperplasia and this finding suggests that the diagnosis of prostate diseases must be considered on evaluation of IMA as a marker of cardiac ischemia.

Phagocytosis, oxidative burst, and produced reactive species are affected by iron deficiency anemia and anemia of chronic diseases in elderly

Iron and oxidative stress have a regulatory interplay. During the oxidative burst, phagocytic cells produce free radicals such as hypochlorous acid (HOCl). Nevertheless, scarce studies evaluated the effect of either iron deficiency anemia (IDA) or anemia of chronic disease (ACD) on phagocyte function in the elderly. The aim of the present study was to determine the oxidative burst, phagocytosis, and nitric oxide (*NO) and HOCl, reactive species produced by monocytes and neutrophils in elderly with ACD or IDA. Soluble transferrin receptor, serum ferritin, and soluble transferrin receptor/log ferritin (TfR-F) index determined the iron status. The study was constituted of 39 patients aged over 60 (28 women and 11 men) recruited from the Brazilian Public Health System. Oxidative burst fluorescence intensity per neutrophil in IDA group and HOCl generation in both ACD and IDA groups were found to be lower (p < 0.05). The percentages of neutrophils and monocytes expressing phagocytosis in ACD group were found to be higher (p < 0.05). There was an overproduction of *NO from monocytes, whereas the fundamental generation of HOCl appeared to be lower. Phagocytosis, oxidative burst, and *NO and HOCl production are involved in iron metabolism regulation in elderly patients with ACD and IDA.

von Willebrand factor, C-reactive protein, nitric oxide, and vascular endothelial growth factor in a dietary reversal model of hypercholesterolemia in rabbit

AIMS

Endothelial dysfunction is considered a sign of the early vascular changes preceding atherosclerosis. We studied the alteration of von Willebrand Factor (vWF), C - reactive protein (CRP), nitrite and Vascular Endothelial Growth Factor (VEGF) in a dietary reversal model of hypercholesterolemia in rabbit.

METHODS

This project was designed in two phases. In phase I, male rabbits (n = 11) were fed a 1% high cholesterol diet for 30 days. Then the diet was replaced with normal rabbit chow for other 30 days (cholesterol withdrawal phase, phase II). To compare the fatty streak formation with normal condition, a control group (n = 6) received normal diet during the study. The serum lipid levels, vWF, CRP, nitrite, and VEGF were measured before the experiment and by the end of each phase. Fatty streak formation in the walls of the aortas in both groups (high cholesterol diet and control group) was determined using intima thickness/media thickness (IMT) ratio.

RESULTS

The results indicate that the level of cholesterol, Low Density Lipoproteins (LDL), vWF and CRP increased significantly in phase I, and decreased after hypercholesterolemic diet withdrawal (p < 0.05). No statistically significant changes were found in VEGF levels but the serum level of nitrite increased significantly during both phases of the study (p < 0.05). The IMT ratio in the walls of aortas was significantly different between the groups in both phases of studies (p < 0.05). There was a significant correlation between nitrite and cholesterol levels in both phases (r = 0.62 and r = 0.98, p < 0.05). Nitrite concentration also correlated with IMT ratio in both phases of the study (r = 0.75 and r = -0.99, p < 0.05). vWF did not correlate with cholesterol but it correlated with IMT ratio in both phases of the study (r = 0.87 and r = 0.84, p < 0.05). CRP only correlated with cholesterol in the first phase (r = 0.91, p < 0.05).

CONCLUSIONS

Among the endothelial biomarkers, vWF was found to be a biological marker for identifying the risk of developing atherosclerosis; however a single biomarker may not provide appropriate information.

C-reactive protein gene polymorphisms affect plasma CRP and homocysteine concentrations in subjects with and without angiographically confirmed coronary artery disease

Human C-reactive protein (CRP) is a reactant involved in the acute phase response and one of the many molecular factors involved in pathogenesis of coronary artery disease (CAD). CRP gene variants potentially mediate CRP plasma concentrations and the development of CAD. 220 Croatian subjects with angiographically confirmed CAD and 132 control subjects were included in the study. CRP gene polymorphisms 1059G/C and -717G/A were determined by RFLPs, using MaeIII and KspI endonuclease, respectively. Plasma concentrations of CRP and homocysteine were determined by immunoturbidimetry and FPIA, respectively. CRP 1059G/C gene variants were significantly associated with CAD (OR = 0.50; 95% CI = 0.27, 0.94; P = 0.032). Wild GG genotype and rare allele C carrier genotypes were 184 and 22 in CAD(+) group, and 101 and 24 in CAD(-) group, respectively. Multivariate analysis with age, gender, BMI, smoking status, hypertension and diabetes as covariates showed that 1059C carriers had lower CRP concentrations in CAD(-) (P = 0.010) and CAD(+) subjects (P = 0.028). This allele was also significantly associated with lower plasma homocysteine concentrations in both groups (P = 0.018 for CAD(-) and 0.002 for CAD(+). There was no significant difference between CAD(+) and CAD(-) subjects in absolute frequencies for CRP -717A/G gene variant, but multivariate analysis showed that carriers of the rarer G allele had significantly higher CRP plasma concentrations in CAD(-) subjects (P = 0.031) and higher homocysteine concentrations in CAD(+) group (P < 0.001). Atherosclerosis is an inflammatory disease resulting from different genetic and environmental factors. Results presented here support the contribution of CRP genetic variations in the development of CAD.

Biochemical Markers of Atherosclerosis

This paper is a brief review of some lipid parameters and serum markers of inflammation in a view of their predictive relevance for the atherosclerotic disease. A discourse on the importance of measuring different lipids and lipoproteins, concentration of LDL particles and apolipoprotein levels is still underway. Also, the recommendations for apolipoprotein (a), phenotypization and other lipid markers have not yet been established. In recent years the recommendations imply simultaneous measuring of multiple markers and calculating the lipid index values such as lipid tetrad index (LTI), lipid pentad index (LPI) and atherogenic index of plasma (AIP). Several circulating markers of inflammation such as C-reactive protein, serum fibrinogen and elevated leukocyte number, are consistently associated with atherosclerosis. In spite of a lack of evidence on measuring the C-reactive protein in a wide population, the guidelines for its application in diagnostics and therapy of coronary heart disease were developed. Some proinflammatory cytokines, adhesion molecules and markers of leukocyte activation are promising markers, requiring, however, more detailed prospective evaluation. The question to be elucidated is if these inflammatory markers are directly involved in the pathogenic process.

Biochemical aspects of inflammation

This review considers biochemical aspects of inflammation. The international literature until December 2006 has been analyzed, with the principal attention paid to the most dynamic problems: enzymology of inflammation, its regulation by hormones and signal transducers, and negative feedbacks, which underlie intensive current studies on pathogenesis, diagnostics, and therapy of inflammation. Such achievements as discoveries of defensins, toll-like receptors, interconnections of inflammation and iron metabolism, the roles of oxidative stress and antioxidant defense, lipoxins, inflammatory components of "non-inflammatory" diseases, and action mechanisms of effective drugs are discussed.