Relationship between the adipose-tissue hormone resistin and coronary artery disease

Differential prognostic value of resistin for cardiac death in patients with coronary artery disease according to the presence of metabolic syndrome

Resistin is associated with atherosclerosis progression by affecting inflammation and insulin resistance. There are controversial data regarding the prognostic value of resistin in stable coronary artery disease (CAD) patients. We prospectively investigated the long-term prognostic value of resistin in patients with stable CAD. A total 741 consecutive patients with stable CAD were followed for a median of 5.5 years. Serum resistin, lipids, high-sensitivity C-reactive protein (hsCRP) and interleukin-6 (IL-6) levels were measured at baseline. Primary endpoints were cardiac death and secondary hospitalizations for acute coronary syndrome, arrhythmic event or ischemic stroke. Follow-up data were obtained from 703 patients of whom 79 had a cardiac death (11.2%) and 205 (29.2%) met the secondary endpoints. Resistin was positively correlated with hsCRP (r = 0.159, p < 0.001) and IL-6 (r = 0.165, p = 0.002), and negatively with high-density lipoprotein-cholesterol (r = - 0.176, p < 0.001). Resistin levels could not predict cardiac death [HR 1.044; 95% CI 0.994-1.096; p = 0.087] neither secondary endpoints [HR 1.025; 95% CI 0.983-1.068; p = 0.250). Among 298 patients (42.4%) with metabolic syndrome (MS) resistin levels were independently associated with cardiac death after adjustment for conventional risk factors [HR 1.121; 95% CI 1.045-1.204; p = 0.002). Further adjustment for ejection fraction of left ventricle (LVEF) did not change the association (HR 1.145; 95% CI 1.057-1.240; p = 0.001). Patients with resistin values ≥ 7.6 ng/mL (median level) had 2.8 times higher risk of cardiac death compared to those with resistin levels < 7.6 ng/mL after adjustment for traditional risk factors and LVEF (HR 2.882; 95% CI 1.311-6.336; p = 0.008). Resistin is independently associated with cardiac death in patients with stable CAD and MS.

Is there a relationship between resistin levels and left ventricular end-diastolic pressure?

Objective:

Resistin, a cysteine-rich peptide, is associated with atherosclerosis and diabetes. Resistin levels increase corresponding to coronary artery disease (CAD) and heart failure severity. Since resistin level tends to elevate with symptomatic heart failure, it is expected to be associated with left ventricular end-diastolic pressure (LVEDP). However, there is no relevant literature on the relationship between resistin levels and LVEDP. We aimed to evaluate the association between resistin levels and LVEDP, severity of CAD, carotid intima-media thickness (CIMT), and echocardiographic diastolic dysfunction parameters.

Methods:

For this study, 128 euvolemic patients with creatinine clearance >50 mg/dL and without acute coronary syndrome, who had typical chest pain or were stress test positive, were enrolled. Resistin level was measured by Enzyme-linked immunosorbent assays (ELISA) method. Severe CAD is defined as ≥50% stenosis in one of the major coronary arteries. LVEDP was measured during left heart catheterization.

Results:

After coronary angiography, 60 patients (46.9%) had severe CAD. The mean LVEDPs were similar for patients with and without severe CAD (p=0.480). The resistin levels did not differ between the groups (p=0.154). The resistin levels did not correlate with LVEDP (r=−0.045, p=0.627), ejection fraction (EF; r=0.110, p=0.228), the Gensini score (r=−0.091, p=0.328), and CIMT (r=0.082, p=0.457). No significant correlation was found between the echocardiographic diastolic dysfunction parameters and resistin levels.

Conclusion:

There was no significant correlation between resistin level and LVEDP, CAD severity, echocardiographic diastolic dysfunction parameters, and CIMT. Further studies are warranted to determine the efficacy of resistin in clinical use.

Suggestive evidence of a multi-cytokine resistin pathway in humans and its role on cardiovascular events in high-risk individuals

In cells and tissues resistin affects IL-1β, IL-6, IL-8, IL-12 and TNF-α expression, thus suggesting the existence of a multi-cytokine “resistin pathway”. We investigated whether such pathway does exist in humans and, if so, if it is associated with cardiovascular risk factors and with major adverse cardiovascular events (MACE). Serum cytokines were measured in 280 healthy subjects from the Gargano Study 2 (GS2) whose BMI, waist circumference, HOMA_IR, triglycerides, HDL-cholesterol, systolic and diastolic blood pressure data were available and in 353 patients with type 2 diabetes and coronary artery disease from the Gargano Heart Study (GHS)-prospective design (follow-up 5.4 ± 2.5 years; 71 MACE). In GS2, cytokines mRNA levels in white blood cells were also measured. In GS2, resistin mRNA was correlated with all cytokines expression (all p < 0.001), but IL-12B. Consistently, serum resistin was correlated with all serum cytokines (all p < 0.001), but IL-12. Expression (eRPS) and serum (sRPS) resistin pathway scores (excluding IL-12) were each other correlated (p < 0.001) and both associated with cardiovascular risk factors (all p < 0.01). In GHS, sRPS was independently associated with MACE (HR = 1.44, 95% CI = 1.10–1.90). Our data indicate the existence of a resistin pathway, which is associated with cardiovascular risk factors and which strongly and independently predicts MACE.

Insights into the molecular mechanisms of diabetes-induced endothelial dysfunction: focus on oxidative stress and endothelial progenitor cells

Diabetes mellitus is a heterogeneous, multifactorial, chronic disease characterized by hyperglycemia owing to insulin insufficiency and insulin resistance (IR). Recent epidemiological studies showed that the diabetes epidemic affects 382 million people worldwide in 2013, and this figure is expected to be 600 million people by 2035. Diabetes is associated with microvascular and macrovascular complications resulting in accelerated endothelial dysfunction (ED), atherosclerosis, and cardiovascular disease (CVD). Unfortunately, the complex pathophysiology of diabetic cardiovascular damage is not fully understood. Therefore, there is a clear need to better understand the molecular pathophysiology of ED in diabetes, and consequently, better treatment options and novel efficacious therapies could be identified. In the light of recent extensive research, we re-investigate the association between diabetes-associated metabolic disturbances (IR, subclinical inflammation, dyslipidemia, hyperglycemia, dysregulated production of adipokines, defective incretin and gut hormones production/action, and oxidative stress) and ED, focusing on oxidative stress and endothelial progenitor cells (EPCs). In addition, we re-emphasize that oxidative stress is the final common pathway that transduces signals from other conditions-either directly or indirectly-leading to ED and CVD.

Segmental peri-coronary epicardial adipose tissue volume and coronary plaque characteristics

AIMS

Epicardial adipose tissue (EAT) has been proposed to modulate underlying coronary plaque features. The study aimed to determine the relation between segmental EAT (sEAT) volume, assessed by cardiac magnetic resonance (CMR), and underlying coronary plaque characteristics, as estimated by multidetector computed tomography (CT) (MDCT).

METHODS AND RESULTS

The study included 32 male patients with stable angina pectoris and 11 age-matched healthy controls. For each CAD patient, sEAT volume around 8 coronary segments (3 in left anterior descending artery, 3 in right coronary artery, and 2 in left circumflex artery) was quantified by CMR. By MDCT, plaques in each coronary segment were characterized in terms of plaque volume, type, CT attenuation, and severity of luminal stenosis. Serum levels of adipokines were measured. Total EAT volume was significantly higher in CAD patients than in control group. Serum resistin showed significant correlation with EAT volume (r = 0.69, P < 0.001). Analysis of 256 coronary segments showed larger sEAT volume with increasing luminal stenosis of the corresponding segment (mild: 8.2 cm(3); moderate: 11 cm(3); severe: 11.8 cm(3), P < 0.001). sEAT volume was larger in segments with mixed than those with calcified or non-calcified plaques (12.1 vs. 10.2 vs. 9.5 cm(3), respectively, P = 0.015). sEAT volume was larger in segments with low CT attenuation non-calcified plaques compared with non-calcified plaques with CT attenuation >30 HU (10.5 vs. 8.2 mm(3), P < 0.001).

CONCLUSION

Peri-coronary epicardial adipose tissue volume is significantly associated with the extent and severity of coronary atherosclerosis and may be a determinant of plaque vulnerability.

Resistin in rodents and humans

Obesity is characterized by excess accumulation of lipids in adipose tissue and other organs, and chronic inflammation associated with insulin resistance and an increased risk of type 2 diabetes. Obesity, type 2 diabetes, and cardiovascular diseases are major health concerns. Resistin was first discovered as an adipose-secreted hormone (adipokine) linked to obesity and insulin resistance in rodents. Adipocyte-derived resistin is increased in obese rodents and strongly related to insulin resistance. However, in contrast to rodents, resistin is expressed and secreted from macrophages in humans and is increased in inflammatory conditions. Some studies have also suggested an association between increased resistin levels and insulin resistance, diabetes and cardiovascular disease. Genetic studies have provided additional evidence for a role of resistin in insulin resistance and inflammation. Resistin appears to mediate the pathogenesis of atherosclerosis by promoting endothelial dysfunction, vascular smooth muscle cell proliferation, arterial inflammation, and formation of foam cells. Indeed, resistin is predictive of atherosclerosis and poor clinical outcomes in patients with coronary artery disease and ischemic stroke. There is also growing evidence that elevated resistin is associated with the development of heart failure. This review will focus on the biology of resistin in rodents and humans, and evidence linking resistin with type 2 diabetes, atherosclerosis, and cardiovascular disease.

Serum resistin, cardiovascular disease and all-cause mortality in patients with type 2 diabetes

Background

High serum resistin has been associated with increased risk of cardiovascular disease in the general population, Only sparse and conflicting results, limited to Asian individuals, have been reported, so far, in type 2 diabetes. We studied the role of serum resistin on coronary artery disease, major cardiovascular events and all-cause mortality in type 2 diabetes.

Methods

We tested the association of circulating resistin concentrations with coronary artery disease, major cardiovascular events (cardiovascular death, non-fatal myocardial infarction and non-fatal stroke) and all-cause mortality in 2,313 diabetic patients of European ancestry from two cross-sectional and two prospective studies. In addition, the expression of resistin gene (RETN) was measured in blood cells of 68 diabetic patients and correlated with their serum resistin levels.

Results

In a model comprising age, sex, smoking habits, BMI, HbA1c, and insulin, antihypertensive and antidyslipidemic therapies, serum resistin was associated with coronary artery disease in both cross-sectional studies: OR (95%CI) per SD increment = 1.35 (1.10–1.64) and 1.99 (1.55–2.55). Additionally, serum resistin predicted incident major cardiovascular events (HR per SD increment = 1.31; 1.10–1.56) and all-cause mortality (HR per SD increment = 1.16; 1.06–1.26). Adjusting also for fibrinogen levels affected the association with coronary artery disease and incident cardiovascular events, but not that with all cause-mortality. Finally, serum resistin was positively correlated with RETN mRNA expression (rho = 0.343).

Conclusions

This is the first study showing that high serum resistin (a likely consequence, at least partly, of increased RETN expression) is a risk factor for cardiovascular disease and all-cause mortality in diabetic patients of European ancestry.

Effect of six-week aerobic exercise on Chemerin and Resistin concentration in hypertensive postmenopausal women

BACKGROUND

Physical activity reduces symptoms of cardiovascular diseases. The aim of this study was to examine the effect of six-week aerobic exercise upon Chemerin and Resistin concentration in women with menopause who had hypertension.

METHODS

The population of this quasi-experimental study included postmenopausal women diagnosed with hypertension. They were 50 to 55 years old and lived in Amol, a city in north part of Iran. Twenty volunteers were filled the personal consent and Health Questionnaire. They were randomly assigned to Experimental and control groups equally (n=10 per group). The experimental group conducted a 6-week aerobic training program from 8-10am every day.

RESULTS

Endurance exercise decreased Chemerin (t=10.41, P<0.000) and Resistin (t=2.42, P<0.051); indicating the decline of inflammation and cardiovascular disease.

CONCLUSION

Considering anti-inflammatory effects of exercise, training plays an important role in reducing inflammatory indices in human; and endurance training can be a good strategy to deal with inflammation and cardiac- vascular risk factors.

Human resistin in cardiovascular disease

An adipokine, resistin, was discovered as a potential mediator of obesity related insulin resistance in rodents. However, the relevance of resistin in human obesity and insulin resistance has been challenged by the difference between human and rodent resistin and the controversies in human epidemiologic studies. Instead, recent human clinical studies and experiments support the idea that human resistin is an inflammatory mediator and a biomarker of cardiovascular diseases, especially in atherosclerosis and heart failure. Thus, we focused on the recent evidence of the role of human resistin in cardiovascular disease.

Resistin and cardiovascular disease

Resistin has been implicated in coronary atherosclerotic disease and congestive heart failure. Recent studies have extended its involvement in peripheral artery disease. Despite some controversial data, the mainstream clinical literature supports that resistin is associated with both coronary and peripheral artery diseases including ischemic stroke. In this review, the multiple roles of resistin as screening, diagnostic, and prognostic marker for cardiovascular disease are discussed. The independence of resistin in disease prediction and diagnosis appears complicated by its confounders, such as C-reactive protein. A clear-cut biomarker function of resistin in cardiovascular disease needs be clarified by additional large-scale, well-designed prospective studies.

Genome-wide association analysis identifies TYW3/CRYZ and NDST4 loci associated with circulating resistin levels

Resistin is a polypeptide hormone that was reported to be associated with insulin resistance, inflammation and risk of type 2 diabetes and cardiovascular disease. We conducted a genome-wide association (GWA) study on circulating resistin levels in individuals of European ancestry drawn from the two independent studies: the Nurses' Health Study (n = 1590) and the Health, Aging and Body Composition Study (n = 1658). Single-nucleotide polymorphisms (SNPs) identified in the GWA analysis were replicated in an independent cohort of Europeans: the Gargano Family Study (n = 659). We confirmed the association with a previously known locus, the RETN gene (19p13.2), and identified two novel loci near the TYW3/CRYZ gene (1p31) and the NDST4 gene (4q25), associated with resistin levels at a genome-wide significant level, best represented by SNP rs3931020 (P = 6.37 × 10(-12)) and SNP rs13144478 (P = 6.19 × 10(-18)), respectively. Gene expression quantitative trait loci analyses showed a significant cis association between the SNP rs3931020 and CRYZ gene expression levels (P = 3.68 × 10(-7)). We also found that both of these two SNPs were significantly associated with resistin gene (RETN) mRNA levels in white blood cells from 68 subjects with type 2 diabetes (both P = 0.02). In addition, the resistin-rising allele of the TYW3/CRYZ SNP rs3931020, but not the NDST4 SNP rs13144478, showed a consistent association with increased coronary heart disease risk [odds ratio = 1.18 (95% CI, 1.03-1.34); P = 0.01]. Our results suggest that genetic variants in TYW3/CRYZ and NDST4 loci may be involved in the regulation of circulating resistin levels. More studies are needed to verify the associations of the SNP rs13144478 with NDST4 gene expression and resistin-related disease.

Quercetin and epigallocatechin gallate induce in vitro a dose-dependent stiffening and hyperpolarizing effect on the cell membrane of human mononuclear blood cells

The bioactivity of polyphenols is closely linked to their ability to interact with biological membranes. The study evaluates the in vitro effect of quercetin and epigallocatechin on the membrane anisotropy and transmembrane potential of peripheral blood mononuclear cells (PBMCs) isolated from 26 type 2 diabetes mellitus patients compared to 25 age matched controls. The in vitro assays were analyzed in correlation with the biochemical and inflammatory profile of the subjects and with insulin resistance parameters (HOMA-IR, plasma resistin) as well. For type 2 diabetes patients, the increase of HOMA-IR and resistin concentration was associated with a significant decrease of the PBMCs membrane anisotropy. The two tested polyphenols induced a dose-dependent hyperpolarizing effect and stiffening of the cell membranes for all tested subjects. Physiological levels of quercetin and epigallocatechin gallate had the tendency to normalize the PBMCs membrane anisotropy of the cells isolated from diabetes patients, bringing it to the level of cells isolated from normoglycemic ones. Epigallocatechin gallate induced higher effects compared to quercetin on the membranes isolated from subjects with higher cardiovascular risk. The decrease of membrane fluidity and the hyperpolarizing effect could explain the cardiovascular protective action of the tested compounds.

Association of resistin with heart failure and mortality in patients with stable coronary heart disease: data from the heart and soul study

BACKGROUND

Resistin is a pro-inflammatory signaling molecule that is thought to contribute to atherosclerosis. We sought to evaluate whether resistin is predictive of worse cardiovascular outcomes among ambulatory patients with stable coronary heart disease (CHD).

METHODS AND RESULTS

We measured baseline serum resistin in 980 participants with documented CHD. After a mean follow-up of 6.1 (range, 0.1 to 9.0) years, 358 (36.5%) were hospitalized for myocardial infarction or heart failure or had died. As compared with participants who had resistin levels in the lowest quartile, those with resistin levels in the highest quartile were at an increased risk of heart failure (hazard ratio [HR], 2.06; 95% confidence interval [CI], 1.26-3.39) and death (HR, 1.56; 95% CI, 1.11-2.18), adjusted for age, sex, and race. Further adjustments for obesity, hypertension, insulin resistance, dyslipidemia, and renal dysfunction eliminated these associations. Resistin levels were not associated with an increased risk of non-fatal myocardial infarction (unadjusted HR, 1.18; 95% CI, 0.68-2.05).

CONCLUSIONS

Elevated serum resistin is associated with higher rates of mortality and hospitalization for heart failure. However, this appears to be explained by the association of resistin with traditional measures of cardiovascular risk. Thus, serum resistin does not add prognostic information among high-risk persons with established CHD.

Serum resistin levels and cardiovascular events in patients undergoing percutaneous coronary intervention

AIM

Resistin is an adipocytokine that may link inflammation and atherosclerosis.We studied the associations of resistin levels with cardiovascular events and restenosis.

METHODS

We measured pre-procedural serum resistin levels in 140 patients with coronary artery disease undergoing elective percutaneous coronary intervention (PCI), of whom 97 had a stent. Restenosis was defined as > 50% stenosis at follow-up angiography. Patients were followed for 3 years for major adverse cardiovascular events (MACE).

RESULTS

At 8±6 months after PCI, reangiography was performed in 94 (67%) patients, of whom 42 had restenosis. Between 42 patients with restenosis and 52 without restenosis, resistin (4.5±2.6 vs. 4.5±2.5 ng/mL) and Creactive protein (CRP) (median 0.70 vs. 0.70 mg/L) levels did not differ. During 3-year follow-up, MACE occurred in 24 patients (1 death, 21 unstable angina, 2 stroke). Compared with 116 patients without MACE, 24 with MACE had higher resistin (5.4±2.4 vs. 4.3±2.5 ng/mL) and CRP (1.30 vs. 0.60 mg/L) levels (p< 0.05). Patients with MACE more often had resistin >4.0 ng/mL than without MACE (75% vs. 35%, p< 0.001). Resistin correlated with CRP levels (r= 0.31). To clarify the association between MACE and resistin, patients were divided into 2 groups by resistin levels. Kaplan-Meier analysis showed a lower event-free survival rate in patients with resistin > 4.0 ng/mL than without it (p< 0.001). On multivariate analysis, resistin, but not CRP, was an independent predictor of MACE. The hazard ratio for MACE was 3.6 (95%CI=1.4-9.2) for resistin > 4.0 ng/mL.

CONCLUSION

Serum resistin levels were found to be associated with further cardiovascular events in patients undergoing PCI.

Plasma adiponectin and resistin levels as predictors of mortality in patients with acute myocardial infarction: data from infarction prognosis study registry

BACKGROUND

Adiponectin and resistin, which have counteracting effects, are suggested to be associated with inflammation and atherosclerosis. The relationship between their levels and prognosis in high risk patients is, however, still unclear. The aim of this study was to evaluate the prognostic values of these adipokines in patients with acute myocardial infarction (MI).

METHODS

Adiponectin and resistin levels were measured at acute phase of MI in 397 consecutive patients. All patients were followed-up for the occurrence of all-cause and cardiovascular mortalities. Predictors for all-cause and cardiovascular mortalities were analyzed by Cox proportional hazard model.

RESULTS

During the mean follow-up period of 12 months, 28 (7.1%) patients died. Unadjusted all-cause mortality rate was significantly higher in patients with high tertiles of adiponectin (P=0.002) and resistin (P=0.002) levels. After controlling of clinical and laboratory variables, age [95% confidence interval (CI): 1.20-2.83, P=0.006], adiponectin (95% CI: 1.01-1.22, P=0.040), resistin (95% CI: 1.06-2.33, P=0.025), and statin use (95% CI: 0.15-0.83, P=0.017) were found to be independent predictors of all-cause mortality. For cardiovascular mortality, only age (95% CI: 1.33-3.25, P=0.001) and renal insufficiency (95% CI: 1.52-12.22, P=0.006) were independent predictors.

CONCLUSION

High plasma adiponectin and resistin levels were predictors for all-cause mortality independent of other risk factors in patients with acute MI. These results confirmed and extended the positive correlations between these adipokines and mortality to a population consisting exclusively of MI.