Usefulness of high-sensitivity IL-6 measurement for clinical characterization of patients with coronary artery disease

Biomarkers to monitor the prognosis, disease severity, and treatment efficacy in coronary artery disease

INTRODUCTION

Coronary Artery Disease (CAD) is a prevalent condition characterized by the presence of atherosclerotic plaques in the coronary arteries of the heart. The global burden of CAD has increased significantly over the years, resulting in millions of deaths annually and making it the leading health-care expenditure and cause of mortality in developed countries. The lack of cost-effective strategies for monitoring the prognosis of CAD warrants a pressing need for accurate and efficient markers to assess disease severity and progression for both reducing health-care costs and improving patient outcomes.

AREA COVERED

To effectively monitor CAD, prognostic biomarkers and imaging techniques play a vital role in risk-stratified patients during acute treatment and over time. However, with over 1,000 potential markers of interest, it is crucial to identify the key markers with substantial utility in monitoring CAD progression and evaluating therapeutic interventions. This review focuses on identifying and highlighting the most relevant markers for monitoring CAD prognosis and disease severity. We searched for relevant literature using PubMed and Google Scholar.

EXPERT OPINION

By utilizing the markers discussed, health-care providers can improve patient care, optimize treatment plans, and ultimately reduce health-care costs associated with CAD management.

Status of biomarkers for the identification of stable or vulnerable plaques in atherosclerosis

Atherosclerosis is a systemic inflammation of the arteries characterized by atherosclerotic plaque due to the accumulation of lipids, inflammatory cells, apoptotic cells, calcium and extracellular matrix (ECM) proteins. Stable plaques present a chronic inflammatory infiltration, whereas vulnerable plaques present an 'active' inflammation involved in the thinning of the fibrous cap that predisposes to plaque rupture. Several complex biological cellular processes lead plaques to evolve from stable to vulnerable predisposing them to rupture and thrombosis. In this review, we analyze some emerging circulating biomarkers related to inflammation, ECM and lipid infiltration, angiogenesis, metalloproteinases and microRNA (miRNA), as possible diagnostic and prognostic indicators of plaque vulnerability.

The effect of polymorphisms (174G> C and 572C> G) on the Interleukin-6 gene in coronary artery disease: a systematic review and meta-analysis

Background

Coronary Artery Disease (CAD) is caused by the blockage of the coronary arteries. it is argued that there has an association between the Interleukin-6 gene and the occurrence of atherosclerosis, coronary artery disease, Due to the short half-life and high variability of Interleukin-6 (IL-6), limited studies have been performed on the association of serum levels of interleukin-6 with coronary artery disease. The aim of this study is to investigate the relationship between IL-6 gene polymorphisms and coronary artery disease.

Methods

This study was conducted as a meta-analysis of selected articles with no lower time limit and upto March 2020. Articles related to the subject were obtained by searching several data sources,such as the SID, IranDoc, Scopus, Embase, Web of Science (ISI), PubMed, Science Direct, and Google Scholar databases. The heterogeneity of the studies was assessed using the I² index in the Comprehensive Meta-Analysis software.

Results

The GG genotype of the IL-6174 G> C polymorphism with a 0.8 odds ratio tended to reduce the risk of CAD by 20%. The odds ratio of CAD in CG and GG genotypes were found to be 1.16 and 1.48 times respectively, indicating the increasing effect of these two genotypes. In the IL-6-572 C>G polymorphism, CG and GG genotypes increased the risk of CAD by 1.21 and 1.27 times respectively, and the CC genotype tended to reduce the risk of CAD by 15%, considering the odds ratio of 0.85.

Conclusion

This study showed a relationship between IL-6174G> C and Interleukin-6 (IL-6) 572 C>G genes and coronary artery disease. Moreover, the protective effects of GG genotype in IL-6 gene 174 G> C and CC genotype in IL-6 gene 572 C>G gene were reported. The study also confirmed that the CG and CC genotypes of the G>C IL-6174 gene have an increasing effect on coronary artery disease. Moreover, CG and GG genotypes in the IL-6 gene 572 C>G increased the risk of developing CAD. It should be noted that the increased risk of developing CAD was limited to meta-analytic studies in reported literatures.

Cardiovascular risk in COVID-19 infection

A few months ago a new coronavirus was identified in Cina officially named by the WHO as COVID-19. The thousands of patients who died showed pneumonia and alveolar damage, but actually, according to several authors in addition to the acute respiratory distress syndrome the virus can give rise to multiorgan failure. In fact, many people died equally despite being intubated and treated for respiratory failure. In this review, we especially wanted to describe the virus effects on the cardiovascular system, probably the leading cause of death of thousands of deceased patients. Therefore, mortality is indirectly induced by the virus through vascular inflammation and cardiovascular damage and patients with severe COVID-19 infection showed significantly increased levels of cardiac troponin I and inflammatory cytokines. The main activation of the signal pathways for the production of inflammatory cytokines are the toll-like receptors that recognize the presence of viral nucleic acids and the ACE-2 receptors, that the virus uses to infect the cells. The binding to ACE-2 also allows to promote high levels of angiotensin II by promoting high levels of blood pressure. High levels of IL-6, IL-1B and IL-8 have been associated with plaque instability and increased thrombotic risk. Furthermore IL-6 is involved in the stimulation of matrix-degrading enzymes such as matrix metalloproteinases, and may contribute to the development of acute coronary syndrome. In addition, TNF-α, IL-1 and IL-6 present in patients with severe COVID-19 are associated with coagulation activation and thrombin generation resulting in disseminated intravascular coagulation or thrombotic microangiopathy. Considering these pathological effects of the virus, anti-inflammatory and anticoagulant treatments are to be considered to avoid cardiovascular events. In this regard, heparin, in addition to its anticoagulant characteristics, has been shown to have good control over inflammation and to be a good anti-viral drug.

Common polymorphism in the cannabinoid receptor gene type 2 (CB2R) rs3123554 are associated with metabolic changes after two different hypocaloric diets with different dietary fatty profiles

BACKGROUND

The role of CB2R gene variants on weight loss after a dietary intervention has been investigated in few studies.

OBJECTIVE

We evaluate the effect of this genetic variant (rs3123554) of CB2R gene on cardiovascular risk factors and weight loss secondary to high monounsaturated fat vs a high polyunsaturated fat hypocaloric diets.

DESIGN

A Caucasian population of 362 obese patients was enrolled. Patients were randomly allocated during 3 months to one of two diets (Diet P high polyunsaturated (PUFAs) fat hypocaloric diet vs, Diet M high monounsaturated (MUFAs) fat hypocaloric diet).

RESULTS

In both genotype groups (GG vs GA+AA), body weight, body mass index (BMI), fat mass, waist circumference and systolic blood pressure decreased after diet P and M. Body weight, BMI, fat mass and waist circumference were higher in A allele carriers than non A allele carriers. The improvement of these parameters was higher in non A allele carriers than A allele carriers. In non A allele carriers with both diets, the decrease of total cholesterol, LDL-cholesterol, insulin and HOMA-IR was higher than A allele carriers after both diets. After diet P, triglyceride levels decrease in non A allele carriers.

CONCLUSION

Our data suggest that carriers of the minor allele of rs3123554 variant of CB2R gene lose less body weight during to different hypocaloric diets with different fatty acid. Moreover, non A-allele carriers showed a better response of LDL-cholesterol, HOMA-IR and insulin levels than A-carriers with both hypocaloric diets.

Relationship between C-reactive protein/albumin ratio and coronary artery disease severity in patients with stable angina pectoris

BACKGROUND

Syntax score (SS), which is an angiographic tool used in grading the complexity of coronary artery disease (CAD), has prognostic importance in coronary artery disease (CAD) and provides important information regarding selection of revascularization strategy. C-reactive protein (CRP) and albumin are indicators of inflammation, and high levels of them are associated with high SS. We aimed to investigate whether baseline CRP to albumin ratio C-Reactive Protein/Albumin Ratio (CAR), an easily available and novel inflammatory marker, is associated with SS.

METHOD

A total 403 consecutive patients with stabile angina pectoris, who underwent coronary angiography for suspected CAD from January 2015 to June 2016, were classified into two groups, low SS (≤22) and intermediate-high SS (>22).

RESULTS

C-Reactive Protein/Albumin Ratio was significantly higher in patients with intermediate-high SS group (P < .001). In multivariate regression analysis, CAR remained an independent predictor of intermediate-high SS group together with hypertension and LDL. The predictive performance of CAR, CRP, and albumin was compared by ROC curve analysis. CAR surpassed CRP and albumin in predicting intermediate-high SS group. CAR >6.3 predicted an intermediate-high SS with sensitivity and specificity of 86.8% and 43.4%, respectively.

CONCLUSION

C-Reactive Protein/Albumin Ratio was more tightly associated with the complexity and severity of CAD than CRP and albumin alone and was found to be an independent predictor for intermediate-high SS group.

Effects of polymorphism rs3123554 in the cannabinoid receptor gene type 2 (CB2R) on metabolic and adiposity parameters after weight loss with two hypocaloric diets

BACKGROUND

The role of CB2R gene variants on weight loss after a dietary intervention remained unclear.

OBJECTIVE

Our aim was to analyze the effects of rs3123554 of CB2R receptor gene on metabolic and adiposity parameters after two different hypocaloric diets in obese subjects.

DESIGN

A Caucasian population of 280 obese patients was enrolled. Patients were randomly allocated during 3 months to one of two diets (Diet I - moderate in carbohydrate. Vs Diet II - normal in carbohydrate).

RESULTS

In both genotype groups (GG vs GA + AA), body weight, body mass index (BMI), fat mass, waist circumference and systolic blood pressure decreased after diet I and II. The decrease of these parameters was higher in non A allele carriers than A allele carriers. Pre- and post-dietary intervention, body weight, BMI, fat mass and waist circumference were higher in A allele carriers than non A allele carriers. In non A allele carriers, the decrease of glucose, insulin, HOMA-IR and Interleukin-6 levels was higher than A allele carriers after both diets.

CONCLUSION

Carriers of the minor allele of rs3123554 variant of CB2R gene loose less body weight during two different hypocaloric diets. The improvement of metabolic parameters was better in no A allele carriers than A allele carriers.

RS 10767664 gene variant in Brain Derived Neurotrophic Factor (BDNF) affect metabolic changes and insulin resistance after a standard hypocaloric diet

BACKGROUND

Role of BDNF variants on change in body weight and cardiovascular risk factors after weight loss remains unclear in obese patients.

OBJECTIVE

Our aim was to analyze the effects of rs10767664 BDNF gene polymorphism on body weight, cardiovascular risk factors and serum adipokine levels after a standard hypocaloric diet in obese subjects.

DESIGN

A Caucasian population of 80 obese patients was analyzed before and after 3months on a standard hypocaloric diet.

RESULTS

Fifty patients (62.5%) had the genotype AA and 30 (37.5%) subjects had the next genotypes; AT (25 patients, 31.3%) or TT (5 study subjects, 6.3%) (second group). In non T allele carriers, the decreases in weight-3.4±2.9kg (T allele group -1.7±2.0kg:p=0.01), BMI -1.5±0.2kg (T allele group -1.2±0.5kg:p=0.02), fat mass-2.3±1.1kg (T allele group -1.7±0.9kg:p=0.009), waist circumference-3.8±2.4cm (T allele group -2.1±3.1cm:p=0.008), triglycerides -13.2±7.5mg/dl (T allele group +2.8±1.2mg/dl:p=0.02), insulin -2.1±1.9mUI/L (T allele group -0.3±1.0mUI/L:p=0.01), HOMA-IR -0.9±0.4 (T allele group -0.1±0.8:p=0.01) and leptin -10.1±9.5ng/dl (T allele group -3.1±0.2ng/dl:p=0.01) were higher than T allele carriers.

CONCLUSION

rs10767664 variant of BDNF gene modify anthropometric and biochemical changes after weight loss with a hypocaloric diet.

The rs1862513 Variant in Resistin Gene-Modified Insulin Resistance and Insulin Levels after Weight Loss Secondary to Hypocaloric Diet

BACKGROUND/AIMS

Polymorphisms of a single nucleotide in RETN have been associated with indexes of insulin resistance. Our aim was to analyze the effects of the rs1862513 RETN gene polymorphism on insulin resistance, insulin levels, and resistin levels changes after 3 months of a low-fat hypocaloric diet.

DESIGN

A Caucasian population of 133 obese patients was analyzed before and after 3 months on a low-fat hypocaloric diet.

RESULTS

Fifty-six patients (42.1%) had the genotype GG (wild group) and 77 (57.9%) patients had the other genotypes; GC (59 patients, 44.4%) or CC (18 patients, 13.5%; mutant group). In wild and mutant genotype groups, weight, body mass index, fat mass, waist circumference, and systolic blood pressure decreased. In the wild genotype group, the decrease in total cholesterol was -13.1 ± 25.3 mg/dL (vs. -4.4 ± 13.7 mg/dL in mutant group: p = 0.004 for group deltas), low density lipoprotein (LDL)-cholesterol was -13.0 ± 21.5 mg/dL (-4.3 ± 10.5 mg/dL: p = 0.007), glucose -7.2 ± 3.5 mg/dL (-0.8 ± 0.2 mg/dL: p = 0.01), insulin -5.6 ± 2.5 mUI/L (-2.9 ± 1.2 mUI/L: p = 0.03) and homeostasis model assessment-insulin resistance (HOMA-IR) -2.5 ± 1.1 (-0.6 ± 1.4: p = 0.02). Leptin levels decreased in both genotypes (-10.1 ± 9.5 ng/dL in wild type group vs. -13.1 ± 0.2 ng/dL in mutant type group: p > 0.05).

CONCLUSION

The present study suggests that the G/G genotype of RETN rs1862513 could be a predictor of the reduction of HOMA-IR, insulin, fasting glucose and LDL cholesterol secondary to a hypocaloric diet in obese subjects.

Effects of a high-protein/low-carbohydrate versus a standard hypocaloric diet on adipocytokine levels and cardiovascular risk factors during 9 months, role of rs6923761 gene variant of glucagon-like peptide 1 receptor

BACKGROUND

The role of GLP-1 R variants on body weight response after dietary intervention is unclear.

OBJECTIVE

The aim was to investigate the role of this polymorphism on cardiovascular risk factors, adipokine levels and weight loss secondary to a high-protein/low-carbohydrate vs. standard hypocaloric diets during 9 months.

DESIGN

211 obese subjects were randomly allocated to one of these two diets for a period of 9 months; diet HP (high protein/low carbohydrate) and diet S (standard).

RESULTS

Ninety-four patients (44.5%) had the genotype GG (wild group) and 117 (55.5%) patients had the next genotypes; GA (89 patients, 42.2%) or AA (28 patients, 13.3%) (mutant group). With both diets and in both genotype groups, body mass index, weight, fat mass, waist circumference and systolic blood pressure decreased. Anthropometric parameters were higher in non-A allele carriers than A allele carriers. With diet HP in both genotypes, LDL cholesterol, total cholesterol, leptin, insulin levels and HOMA-R decreased. With the diet S and only in wild genotype, the same parameters decreased, too.

CONCLUSION

Our data showed a lack of association of rs6923761 GLP-1 R polymorphism with weight loss. Better anthropometric parameters in obese subjects with the mutant allele (A) of rs6923761 GLP-1 R polymorphism were observed. Total cholesterol, LDL cholesterol, insulin levels and HOMA-R decreased in all patients with both diets, although A allele carriers treated with standard diet did not show these changes.

Gender-related drug effect on several markers of oxidation stress in diabetes patients with and without complications

We previously reported that circulating lipid (malondialdehyde, MDA) and protein oxidation (carbonyl residues, CO) products can be used as markers of risk for complications in poorly controlled type 2 diabetics. Now, we aimed to evaluate the existence of a gender effect on classical disease markers and oxidative stress parameters and on the effectiveness of metformin and/or statins in reducing CV risk in poorly controlled type 2 diabetics with and without complications. Our results show that diabetics with complications had higher plasma levels of FRAP, SOD and hs-CRP than those without complications, with FRAP and SOD found increased in both genders. Interestingly, male and female patients with complications had higher plasma levels of hs-CRP and MDA respectively, over patients without complications. Multivariate analysis indicated metformin and statin treatments effective in reducing plasma hs-CRP only in female and not in male diabetics with complications. In these latter females, a positive correlation between hs-CRP and triglycerides (TG) levels was found suggesting a causal relationship between them. Statin treatment was effective in reducing MDA in diabetics with complications irrespective of the gender. These data support the addition of statins to diabetic standard therapy to control oxidation injury and inflammation and, for the first time, indicate female patients with complications more responsive than males to the CV protection offered by metformin.

Effect of rs6923761 gene variant of glucagon-like peptide 1 receptor on metabolic response and weight loss after a 3-month intervention with a hypocaloric diet

BACKGROUND

Studies of the GLP-1 receptor (GLP-1 R) have been directed at identifying polymorphisms in the GLP-1 R gene that may be a contributing factor in the pathogenesis of obesity and cardiovascular risk factors. Nevertheless, the role of GLP-1 R variants on body weight response after dietary intervention has not been evaluated.

OBJECTIVE

We decided to analyze the effects of the rs6923761 GLP-1 R polymorphism on body weight changes and metabolic parameters after 3 months of a hypocaloric diet.

DESIGN

A sample of 91 obese subjects was analyzed in a prospective way. The hypocaloric diet had 1,520 calories per day; 52 % of carbohydrates, 25 % of lipids and 23 % of proteins. Distribution of fats was: 50.7 % of monounsaturated fats, 38.5 % of saturated fats and 11.8 % of polyunsaturated fats.

RESULTS

In both genotype groups (GG vs. GA + AA), weight, body mass index, fat mass, waist circumference, systolic blood pressure, total cholesterol, LDL cholesterol, leptin, insulin and HOMA levels decreased. No statistical differences were detected in these changes between genotypes. In wild group (GG genotype) (pretreatment and posttreatment), BMI, weight, fat mass, waist circumference and triglyceride levels were higher than (GA + AA) group.

CONCLUSION

Our data showed better anthropometric parameters and triglyceride levels in obese subjects with the mutant allele (A) of rs6923761 GLP-1R polymorphism. A lack of association of this polymorphism with weight loss or biochemical changes after a hypocaloric diet was observed.

Cardiovascular risk factors and adipocytokines levels after two hypocaloric diets with different fat distribution in obese subjects and rs6923761 gene variant of glucagon-like peptide 1 receptor

BACKGROUND

The role of GLP-1 R variants on body weight response after dietary intervention is unclear.

OBJECTIVE

Our aim was to evaluate the effect of this polymorphism on cardiovascular risk factors, adipokine levels and weight loss secondary to a high monounsaturated fat vs. a high polyunsaturated fat hypocaloric diets in obese subjects.

DESIGN

391 obese subjects were randomly allocated to one of these two diets for a period of 3 months; diet M (high monounsaturated fat hypocaloric diet) and diet P (high polyunsaturated (PUFAs) fat hypocaloric diet).

RESULTS

Two hundred and twelve patients (54.2 %) had the genotype GG (wild group) and 179 (45.8 %) patients had the next genotypes; GA (146 patients, 37.3 %) or AA (33 patients, 8.7 %) (Mutant group). With both diets and in wild-type and mutant-type groups, BMI, weight, fat mass, waist circumference and systolic blood pressure decreased. Anthropometric parameters were higher in non-A-allele carriers than A-allele carriers. With both diets and in both genotypes, leptin, insulin levels and HOMA decreased. With the diet P and in wild genotype, total cholesterol and LDL-cholesterol levels decreased, too.

CONCLUSION

Our data showed a lack of association of rs6923761 GLP-1 R polymorphism with weight loss after a high monounsaturated fat and a high polyunsaturated fat hypocaloric diets. Better anthropometric parameters in obese subjects with the mutant allele (A) of rs6923761 GLP-1 R polymorphism were observed. Insulin levels and HOMA decreased in non-A carriers.

Relation of the rs6923761 gene variant in glucagon-like peptide 1 receptor with weight, cardiovascular risk factor, and serum adipokine levels in obese female subjects

BACKGROUND

Studies of the glucagon-like peptide 1 (GLP-1) receptor have been directed at identifying polymorphisms in the GLP-1 receptor gene that may be a contributing factor in the pathogenesis of diabetes mellitus and cardiovascular risk factors. Nevertheless, the role of GLP-1 variants on body weight, cardiovascular risk factors, and adipokines remains unclear in obese patients.

OBJECTIVE

Our aim was to analyze the effects of rs6923761 GLP-1 receptor polymorphism on body weight, cardiovascular risk factors, and serum adipokine levels in nondiabetic obese females.

DESIGN

A sample of 645 obese nondiabetic Caucasian females was enrolled in a prospective way. Basal fasting glucose, c-reactive protein (CRP), insulin, insulin resistance (homeostasis model assessment (HOMA)), total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides concentration, and adipokines were measured. Weights, body mass index (BMI), waist circumference, fat mass by bioimpedance, and blood pressure measures were measured.

RESULTS

Three hundred and twenty-seven participants (50.7%) had the genotype GG and 318 (49.3%) study subjects had the next genotypes; GA (270 study subjects, 41.9%) or AA (48 study subjects, 7.4%) (second group). In wild group (GG genotype), BMI (1.8 ± 2.3 kg/m(2) ; P < 0.05), weight (3.1 ± 1.3 kg; P < 0.05), fat mass (2.4 ± 1.1 kg; P < 0.05), waist circumference (2.7 ± 1.9 cm; P < 0.05), triglyceride levels (10.4 ± 5.3 mg/dl; P < 0.05), interleukin 6 (IL-6) (1.5 ± 0.9 ng/dl; P < 0.05), resistin (1.1 ± 0.3 ng/dl; P < 0.05), and leptin (30.1 ± 10.3 ng/dl; P < 0.05) levels were higher than mutant group (GA + AA).

CONCLUSION

Data from our study revealed an association with decreased metabolic and cardiovascular markers in obese females. BMI weight, fat mass, waist circumference, triglycerides, leptin, resistin, and IL-6 serum levels were lower in subjects with A allele than non-A allele subjects.

Protein Kinase C Inhibitors as Modulators of Vascular Function and their Application in Vascular Disease

Blood pressure (BP) is regulated by multiple neuronal, hormonal, renal and vascular control mechanisms. Changes in signaling mechanisms in the endothelium, vascular smooth muscle (VSM) and extracellular matrix cause alterations in vascular tone and blood vessel remodeling and may lead to persistent increases in vascular resistance and hypertension (HTN). In VSM, activation of surface receptors by vasoconstrictor stimuli causes an increase in intracellular free Ca(2+) concentration ([Ca(2+)]i), which forms a complex with calmodulin, activates myosin light chain (MLC) kinase and leads to MLC phosphorylation, actin-myosin interaction and VSM contraction. Vasoconstrictor agonists could also increase the production of diacylglycerol which activates protein kinase C (PKC). PKC is a family of Ca(2+)-dependent and Ca(2+)-independent isozymes that have different distributions in various blood vessels, and undergo translocation from the cytosol to the plasma membrane, cytoskeleton or the nucleus during cell activation. In VSM, PKC translocation to the cell surface may trigger a cascade of biochemical events leading to activation of mitogen-activated protein kinase (MAPK) and MAPK kinase (MEK), a pathway that ultimately increases the myofilament force sensitivity to [Ca(2+)]i, and enhances actin-myosin interaction and VSM contraction. PKC translocation to the nucleus may induce transactivation of various genes and promote VSM growth and proliferation. PKC could also affect endothelium-derived relaxing and contracting factors as well as matrix metalloproteinase (MMPs) in the extracellular matrix further affecting vascular reactivity and remodeling. In addition to vasoactive factors, reactive oxygen species, inflammatory cytokines and other metabolic factors could affect PKC activity. Increased PKC expression and activity have been observed in vascular disease and in certain forms of experimental and human HTN. Targeting of vascular PKC using PKC inhibitors may function in concert with antioxidants, MMP inhibitors and cytokine antagonists to reduce VSM hyperactivity in certain forms of HTN that do not respond to Ca(2+) channel blockers.

Fatty acid-binding protein 2 Ala54Thr genotype is associated with insulin resistance and leptin levels changes after a high monounsaturated fat diet in obese non-diabetic patients

BACKGROUND

It has been found that the expression of fatty acid binding protein 2 (FABP2) mRNA is under dietary control. This polymorphism was associated with high insulin resistance, and fasting insulin concentrations.

OBJECTIVE

The aim of our study was to investigate the influence of Thr54 polymorphism in the FABP2 gene on metabolic response, weight loss and serum adipokine levels secondary to a high monounsaturated fat hypocaloric diet.

DESIGN

A sample of 122 obese patients was analyzed in a prospective way. The hypocaloric diet had 1342 kcal, 46.6% of carbohydrates, 34.1% of lipids and 19.2% of proteins, with a 67.5% of monounsaturated fats, and lasted 3 months.

RESULTS

Fifty-five patients (45.1%) had the genotype Ala54/Ala54 (wild group) and 67 (64.9%) patients a mutant genotype, Ala54/Thr54 (54 patients, 44.3%) or Thr54/Thr54 (13 patients, 10.7%). In wild group, body mass index (-1.5±1.2 kg/m2), weight (-4.1±3.6 kg), fat mass (-3.6±3.3 kg), waist circumference (-4.9±2.9 cm), insulin (-1.7±3.6 mUI/l), homeostasis model assessment of insulin resistance (HOMA-IR) (-0.6±1.8 units) and leptin levels decreased (-7.6±7.1 ng/ml). In mutant group, anthropometric parameters improved, without changes in biochemical parameters.

CONCLUSION

Carriers of Thr54 allele have a different response than wild type obese, with a lack of decrease of insulin levels, leptin levels and HOMA-IR.

The interleukin-6 -147 g/c polymorphism is associated with increased risk of coronary artery disease in young South African Indian men

BACKGROUND

Interleukin-6 (IL-6) is a proinflammatory cytokine involved in the pathogenesis of chronic inflammatory diseases such as coronary artery disease (CAD). The -174 IL-6 G/C promoter polymorphism influences mRNA levels and protein expression and is implicated in CAD. The Indian population in South Africa, unlike the black community, has a high prevalence of premature CAD. This polymorphism has not been fully explored in this population. The present study assessed the -174 IL-6 G/C polymorphism in young Indian patients with angiographically documented CAD and compared them with age- and gender-matched Indian and black control subjects.

METHODS

Polymorphic variants were assessed by polymerase chain reaction-restriction fragment length polymorphism, and IL-6 levels were measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS

The -174 IL-6 C allele was found with a higher frequency (23%) in the total Indian group compared to 2% in the black participants [P<0.0001, odds ratio (OR)=0.05, 95% confidence interval (CI) 0.018-0.14). The difference in frequency was more pronounced when Indian controls were compared to black controls (29% vs. 2%, respectively) (P<0.0001, OR=0.05, 95% CI 0.02-0.17). A significant association between the -174 IL-6 G allele and CAD was found in Indian patients compared to Indian controls (84% in cases vs. 71% in Indian controls; P=0.043, OR=0.47 95% CI 0.23-0.95). Levels of IL-6 in circulation were higher in black controls (6.62±0.63 pg/mL) compared to Indian controls (2.51±0.57 pg/mL) and CAD patients (1.46±0.36 pg/mL) (P<0.0001). Levels of IL-6 were higher in all groups with homozygous -174 IL-6 C alleles, but only significant in the healthy Indian control group (GG 3.73±0.94 pg/mL vs. GC/CC 0.89±0.5 pg/mL, P=0.0001).

CONCLUSION

The presence of the IL-6 -174 G allele influences levels of IL-6 and increases the risk of CAD in South African Indians.

Evaluation of weight loss and adipocytokines levels after two hypocaloric diets with different macronutrient distribution in obese subjects with rs9939609 gene variant

BACKGROUND

Common polymorphisms of the fat mass and obesity associated gene (FTO) have been linked to obesity in some populations. One of these genetic variants (rs9939609) has been related to an increased risk of obesity.

OBJECTIVE

Our aim was to evaluate weight loss and adipocytokine levels after two hypocaloric diets with different macronutrient distribution in obese subjects with RS9939609 gene variant.

DESIGN

305 obese patients were enrolled in a prospective way. In the basal visit, patients were randomly allocated during 3 months to low carbohydrates and low fat.

RESULTS

After treatment with both diets and in both genotypes, weight, fat mass, waist circumference and systolic blood pressures decreased. With the diet type I and in TT genotype, insulin (-6.6 ± 9.8 IU/L) and homeostasis model assessment (-2.9 ± 6.1 units) decreased. With the diet type II and in both genotypes (wild and mutant type), insulin (-5.2 ± 6.1 vs. -3.8 ± 6.1 IU/L; p < 0.05) and homeostasis model assessment (-2.4 ± 4.8 vs. -1.1 ± 3.8 kg; p < 0.05) decreased. In the A allele group, a significant decrease was detected in total cholesterol levels (-11.5 ± 20.1 mg/dL), low density lipoprotein cholesterol levels (-13.2 ± 20.9 mg/dL) and c-reactive protein levels (-1.3 ± 3.8 mg/dL) secondary to weight loss after treatment with diet II. The decrease of leptin levels was higher in mutant type group than wild type group with low fat diet (-10.3 ± 36.1 vs. -28.6 ± 53.7 ng/mL; p < 0.05).

CONCLUSION

Metabolic improvement secondary to weight loss was better in A carriers with a low fat hypocaloric diet.

Relationship among metabolic syndrome, C358A polymorphism of the endocannabinoid degrading enzyme fatty acid amide hydrolase (FAAH) and insulin resistance

BACKGROUND

It has been demonstrated that the polymorphism 385 C/A of FAAH (fatty acid amide hydrolase) was associated with obesity and metabolic disorders.

OBJECTIVE

The aim of our study was to investigate the relationship of the polymorphism (cDNA 385 C->A) of FAAH gene and insulin resistance in obese patients with and without metabolic syndrome.

DESIGN

A population of 799 obese patients was analyzed in cross-sectional survey. A bioimpedance, blood pressure, serial assessment of nutritional intake with 3 days written food records and biochemical analysis were performed. Genotype of FAAH gene polymorphism was studied.

RESULTS

Prevalence of metabolic syndrome (MS) with ATP III definition was 49.8% (398 patients) and 50.2% patients without MS (n=401 patients). Prevalence of FAAH genotypes was similar in patients with metabolic syndrome (69.6% wild genotype and 30.4% mutant genotype) and without metabolic syndrome (66.6% wild genotype and 33.4% mutant genotype). In patients without metabolic syndrome, insulin and HOMA levels were higher in mutant genotype than wild type group.

CONCLUSION

The main finding is the lack of association of the FAAH genotypes with metabolic syndrome prevalence. Patients with mutant genotype group of FAAH gene and without metabolic syndrome have higher insulin and HOMA levels than wild type group.

Metabolic syndrome and ALA54THR polymorphism of fatty acid-binding protein 2 in obese patients

The prevalence of metabolic syndrome (MS) has been estimated to be approximately 25% of the population at large. A transition G to A at codon 54 of fatty acid-binding protein 2 (FABP2) results in an amino acid substitution (ala54 to Thr54), and this polymorphism was associated with some cardiovascular risk factors. The aim of our study was to investigate the relationship between MS and Thr54 polymorphism in the FABP2 gene in obese patients. A population of 750 (body mass index >30) obese patients was analyzed in cross-sectional survey. Bioimpedance, blood pressure, and serial assessment of nutritional intake with 3-day written food records and biochemical analysis were performed. The statistical analysis was performed for the combined Ala54/Thr54 and Thr54/Thr54 as a mutant group and wild-type Ala54/Ala54 as second group. Prevalence of MS with Adult Treatment Panel III definition was 49.7% (373 patients; 24.9% male and 75.1% female), and 50.3% of the patients had no MS (n = 377; 34.2% male and 65.8% female). Prevalence of FABP genotypes was similar in patients with MS (55.5% wild genotype and 44.5% mutant genotype) and without MS (54.6% wild genotype and 45.4% mutant genotype). Prevalence of each criteria of MS was calculated in wild- and mutant-type genotypes, without statistical differences. No differences in anthropometric and biochemical parameters were detected between genotypes in the same group of MS. The finding of our study is the lack of association of the Thr54/Ala54 and Thr54/Thr54 FABP2 genotypes with MS.

Influence of G1359A polymorphism of the cannabinoid receptor gene on anthropometric parameters and insulin resistance in women with obesity

A silent polymorphism (1359 G/A) of the cannabinoid receptor gene was reported as a common polymorphism in white populations. The aim of our study was to investigate the influence of this polymorphism (G1359A) of cannabinoid receptor gene on obesity, insulin resistance, and adipocytokines in women with obesity. A population of 290 women was analyzed. Indirect calorimetry, tetrapolar electrical bioimpedance, blood pressure measurement, serial assessment of nutritional intake with 3-day written food records, and biochemical analysis were performed. One hundred fifty-nine patients (54.8%) had the genotype G1359G (wild-type group), and 131 (45.2%) patients had G1359A (116 patients, 40.0%) or A1359A (15 patients, 5.2%) (mutant-type group). Triglycerides (122.3 ± 65.9 vs 107.2 ± 44.8 mg/dL, P < .05), insulin (15.8 ± 9.4 vs 13.6 ± 6.9 mUI/L, P < .05), and homeostasis model assessment values (3.85 ± 2.2 vs 3.33 ± 1.9, P < .05) were higher in the wild-type group than the mutant-type group. High-density lipoprotein cholesterol levels (56.8 ± 24.1 vs 58.3 ± 13.9 mg/dL, P < .05) were higher in the mutant-type group than the wild-type group. The novel finding of this study is the association of the mutant-type group G1359A and A1359A with a better cardiovascular profile (triglyceride, high-density lipoprotein cholesterol, insulin, and homeostasis model assessment levels) than the wild-type group.

Effects of C358A missense polymorphism of the degrading enzyme fatty acid amide hydrolase on weight loss, adipocytokines, and insulin resistance after 2 hypocaloric diets

It has been demonstrated that the polymorphism 385 C/A of fatty acid amide hydrolase was associated with obesity. We decided to investigate the role of a polymorphism (cDNA 385 C->A) on insulin resistance and weight loss secondary to a low-fat vs a low-carbohydrate diet. A population of 248 patients with obesity was analyzed. Basal measurements were performed, and values were compared to those at the end of a 3-month period in which subjects received either diet I (low fat) or diet II (low carbohydrate). One hundred seventy-eight patients (71.8%) had the genotype C358C (wild-type group), and 70 (28.2%) patients had the genotype C358A (62 patients, 25%) or A358A (8 patients, 3.2%) (mutant-type group). With diet I, body mass index, weight, fat mass, waist circumference, and systolic blood pressures decreased in the wild-type and mutant-type groups. With diet II, body mass index, weight, fat mass, waist circumference, and systolic blood pressures decreased in both genotypes. With diet I, leptin, glucose, total cholesterol, triglyceride, insulin, and homeostasis model assessment for insulin sensitivity (HOMA) decreased in the wild-type group. In the mutant-type group, only cholesterol decreased in a significant way. With diet II, leptin, interleukin-6, glucose, total cholesterol, low-density lipoprotein cholesterol, insulin, HOMA, and C-reactive protein decreased in the wild-type genotype. The allele A358 of fatty acid amide hydrolase was associated with a lack of improvement on glucose insulin, HOMA, and leptin levels in both diets after weight loss.

C358A missense polymorphism of the endocannabinoid degrading enzyme fatty acid amide hydrolase (FAAH) and insulin resistance in patients with diabetes mellitus type 2

BACKGROUND

The polymorphism 385 C/A of FAAH has been associated with overweight and obesity. The aim of our study was to investigate the relationship of polymorphism (cDNA 385 C-->A) of FAAH gene on obesity parameters in patients with diabetes mellitus type 2.

DESIGN

A population of 70 patients with diabetes mellitus type 2 was analyzed. An anthropometric and biochemical nutritional assessment was performed. The statistical analysis was performed for the combined C358A and A358A as a group and wild type C358C as second group.

RESULTS

Fifty-five patients (78.7%) had genotype C358C (wild type group) and 15 (21.3%) patients C358A (14 patients, 20.6%) or A358A (1 patient, 0.7%) (mutant group). BMI (38.9+/-6.4 vs. 39.2+/-5.7, p<0.05), weight (96.8+/-17.6kg vs. 102.5+/-16.8kg, p<0.05), fat mass (42.1+/-16.1kg. vs. 46.9+/-11.1kg, p<0.05), waist circumference (115.9+/-12.8cm vs. 121.3+/-12.8cm, p<0.05), insulin (22.5+/-18.8mUI/L vs. 33.9+/-17.1UI/L, p<0.05) and TNF-alpha (6.1+/-3.4pg/mL vs. 8.4+/-3.2pg/mL, p<0.05) were higher in mutant type group than wild type. Adiponectin levels (33.3+/-20.8ng/mL vs. 22.3+/-10.8ng/mL, p<0.05) were higher in wild type group than mutant type group.

CONCLUSION

There is an association of the mutant type group A358C and A358A of FAAH with a worse cardiovascular profile (weight, body mass index, waist circumference, insulin,TNF-alpha and adiponectin levels) than wild type group.

Interleukin-6 plasma level increases with age in an Italian elderly population ("The Treviso Longeva"-Trelong-study) with a sex-specific contribution of rs1800795 polymorphism

The transcription rate of interleukin-6 (IL-6) can be reduced by the C-allele of a polymorphism (rs1800795) located in the 5'-flanking region of the IL-6 gene (NM_000600), and IL-6 plasma levels increase with age. We assembled an elderly Italian population ["The Treviso Longeva (Trelong) study", age range 70-106 years, n = 668 subjects] and assessed rs1800795 genotype and plasma IL-6 concentrations. The rs1800795 genotype was also assessed in an independent Italian study ("Milan" study, age range 70-96, n = 245 subjects). To verify an age- or sex-specific effect of rs1800795 genotype we compared people younger (70-85) and older (85+) than 85 years of age. We found a significant reduction in the frequency of rs1800795 C/C genotype in 85+ men from the Trelong study, while in the Milan study this data did not reach significance. However, considering the two studies together, the frequency of the rs1800795 C/C genotype was significantly lower in 85+ than in 70-85 males (4.0% and 10.7%, respectively), while it remained unchanged in females. As for IL-6 plasma levels, after a multivariate analysis to control for confounders, a correlation between age and plasma IL-6 concentrations was revealed (P < 0.0001). An increase in circulating IL-6 levels in the entire 85+ group compared to the 70-85 group (P < 0.05, Tukey's test) was also noticed. We suggest a sex-specific pattern for genetic variability linked to inflammatory response and longevity, consistent with the age-related increase in IL-6.

Single molecule studies of multiple-fluorophore labeled antibodies. Effect of homo-FRET on the number of photons available before photobleaching

Advancements in single molecule detection (SMD) continue to unfold powerful ways to study the behavior of individual and complex molecular systems in real time. SMD enables the characterization of complex molecular interactions and reveals basic physical phenomena underlying chemical and biological processes. We present here a systematic study of the quenching efficiency of Förster-type energy-transfer (FRET) for multiple fluorophores immobilized on a single antibody. We simultaneously monitor the fluorescence intensity, fluorescence lifetime, and the number of available photons before photobleaching as a function of the number of identical emitters bound to a single IgG antibody. The detailed studies of FRET between individual fluorophores reveal complex through-space interactions. In general, even for two or three fluorophores immobilized on a single protein, homo-FRET interactions lead to an overall non-linear intensity increase and shortening of fluorescence lifetime. Over-labeling of protein in solution (ensemble) results in the loss of fluorescence signal due to the self-quenching of fluorophores making it useless for assays applications. However, in the single molecule regime, over-labeling may bring significant benefits in regards to the number of available photons and the overall survival time. Our investigation reveals possibilities to significantly increase the observation time for a single macromolecule allowing studies of macromolecular interactions that are not obscured by ensemble averaging. Extending the observation time will be crucial for developing immunoassays based on single-antibody.

Plasma N-epsilon-(carboxymethyl)lysine levels are associated with the extent of vessel injury after coronary arterial stenting

OBJECTIVE

In animal models, increased tissue receptor for advanced glycation end products and its ligands, including N-epsilon-(carboxymethyl)lysine (CML), are critically implicated in postprocedural intimal hyperplasia after balloon injury. In patients undergoing percutaneous coronary interventions with stenting, we investigated whether plasma levels of CML and the soluble form of receptor for advanced glycation end products (sRAGE) changed during poststenting follow-up.

METHODS

We studied 81 patients with coronary artery disease who underwent successful percutaneous coronary interventions. Plasma levels of CML and sRAGE were measured before intervention, and at 1 day and 180 days of follow-up.

RESULTS

CML levels increased significantly at day 1 after stenting and persisted at an elevated level at 180 days (P=0.013), whereas sRAGE levels increased significantly at 180 days (P=0.011). CML levels were significantly higher in multivessel-treated patients than in single-vessel-treated patients both at 1 day and 180 days of follow-up. In addition, CML values were positively associated with the extent of stent area at 1 day and 180 days of follow-up (r=0.278, P=0.022 and r=0.315, P=0.012, respectively). In logistic regression analysis, only the extent of stent area predicted adverse clinical events at 180-day follow-up (P=0.03, odds ratio=14.25, confidence interval=1.25-162.2).

CONCLUSION

This study supports the hypothesis that increased circulating levels of CML occurred in the presence of vascular injury. This persistent rise of CML could amplify an inflammatory phenomenon triggered by stent placement and thus contributes to coronary artery disease progression.

Influence of Ala54Thr polymorphism of fatty acid-binding protein 2 on weight loss and insulin levels secondary to two hypocaloric diets: a randomized clinical trial

OBJECTIVE

A transition G to A at codon 54 of FABP2 was associated with high insulin resistance and different dietary response. The aim of our study was to investigate the influence of this polymorphism on weight loss and metabolic changes secondary to two hypocaloric diets.

SUBJECTS AND METHODS

A sample of 204 obesity patients was analyzed. Before and after 2 months of hypocaloric diet, a nutritional evaluation was performed. Patients were randomly allocated to diet I (low-fat diet) or II (low carbohydrate diet).

RESULTS

With diet Type I and in the wild group (Ala54/Ala54), BMI, weight, fat mass, waist circumference, waist to hip ratio, systolic and diastolic blood pressures, total cholesterol, triglyceride and insulin levels decreased. In the mutant group (Ala54/Thr54 and Thr54/Thr54), BMI, weight, waist circumference and fat mass decreased. In the wild group with diet Type II, the same parameters that group I decreased and glucose levels, too. In the mutant group, BMI, weight, waist circumference and fat mass decreased. Only leptin levels have a significant decrease in the wild group with both diets (diet I: 30.7%; p<0.05 and diet II: 15.85%; p<0.05).

CONCLUSION

Similar weight loss is associated with different changes, depending on the FABP genotype with both diets. Weight loss is associated with a more deep decrease in serum leptin concentration with low-fat diet.

Effect of psyllium fiber supplementation on C-reactive protein: the trial to reduce inflammatory markers (TRIM)

PURPOSE

Recent evidence supports a significant association between the intake of dietary fiber and levels of inflammatory markers. The objective of this study was to determine whether daily fiber supplementation would reduce levels of inflammatory markers.

METHODS

This study was a prospective randomized controlled trial at a single university medical center. Participants were overweight or obese adults with no history of heart disease. The intervention was psyllium supplementation at either 7 or 14 g/d for 3 months compared with no supplements in a control group. The main outcome measure was change in level of high-sensitivity C-reactive protein (hsCRP) concentration; secondary outcomes included changes in interleukin-6 (IL-6) levels, fibrinogen levels, and white blood cell (WBC) count. Protocol completers attended at least 2 visits and took more than 75% of the prescribed fiber dose.

RESULTS

In this intent-to-treat analysis (n = 158), there were no significant differences between either of the 2 treatment groups and the control group in the amount of change in CRP, fibrinogen, or IL-6 levels or in WBC count (P>.05). In the analysis of protocol completers (n = 132), there also were no significant differences between the groups except for a small decrease in fibrinogen level in the high-fiber group (-6 mg/dL [-0.18 micromol/L] compared with 13 mg/dL [0.38 micromol/L] in the control group, P<.05).

CONCLUSION

Psyllium fiber supplementation did not significantly reduce CRP levels in overweight or obese individuals in this trial, and changes in other markers were not consistent. Further research is needed to determine whether other fibers or nutrients can reduce inflammatory markers.

Influence of ALA54THR Polymorphism of Fatty Acid Binding Protein 2 on Lifestyle Modification Response in Obese Subjects

BACKGROUND/AIM

It has been found that the expression of fatty acid binding protein 2 (FABP2) mRNA is under dietary control. A G-to-A transition at codon 54 of FABP2 results in an amino acid substitution (from Ala 54 to Thr 54). This polymorphism was associated with high insulin resistance and high fasting insulin concentrations. The aim of our study was to investigate the influence of Thr54 polymorphism in the FABP2 protein on the response to a lifestyle modification (Mediterranean hypocaloric diet and exercise) in obese patients.

METHODS

A population of 69 obese (body mass index > 30) nondiabetic outpatients was analyzed in a prospective way. Before and after 3 months of the lifestyle modification program, indirect calorimetry, tetrapolar electrical bioimpedance measurement, blood pressure recording, serial assessment of the nutritional intake (3 days of written food records), and biochemical analysis were performed. The lifestyle modification program consisted of a hypocaloric diet (1,520 kcal; 52% carbohydrates, 25% lipids, and 23% proteins). The exercise program consisted of aerobic exercise for at least three times/week (60 min each). Statistical analysis was performed for combined Ala54/Thr54 and Thr54/Thr54 as a mutant group and wild-type Ala54/Ala54 as second group.

RESULTS

The mean age was 45.5 +/- 16.7 years, the mean body mass index was 34.1 +/- 5.1, and there were 14 males (20.3%) and 55 females (79.7%) with a weight loss of 3.17 +/- 3.5 kg (3.5%). Thirty-seven patients (53.6%) had the genotype Ala54/Ala54 (wild-type group) and 32 (46.4%) patients either the genotype Ala54/Thr54 (26 patients, 30.2%) or the genotype Thr54/Thr54 (6 patients, 16.2%). The percentage of responders (weight loss) was similar in both groups (89.2 vs. 90.6%). In the wild-type group, body mass index, weight, fat mass, low-density lipoprotein cholesterol level, and waist circumference decreased, whereas the VO2 (oxygen consumption) increased. In the mutant group, glucose, body mass index, weight, waist circumference, and systolic blood pressure decreased, and VO2 increased. No differences were detected between basal values in both groups. Only the leptin levels showed a significant decrease in the wild-type group (23.85%; p < 0.05), with no statistically significant difference in the mutant group (2.59%; NS). Resistin, tumor necrosis factor alpha, interleukin 6, insulin, and C-reactive protein remained without changes in both groups.

CONCLUSIONS

Weight loss is associated with different changes, depending on the FABP2 genotype. Carriers of the Thr54 allele have a different response than wild-type obese subjects, with a significant decrease of systolic blood pressure and glucose levels in Thr54 carriers and a significant decrease in fat mass, low-density lipoprotein cholesterol, and leptin in wild-type patients.