Association between anti-human heat shock protein-60 and interleukin-2 with coronary artery calcium score

Heat Shock Proteins (HSPs) and Cardiovascular Complications of Obesity: Searching for Potential Biomarkers

Heat shock proteins (HSPs), a family of proteins that support cellular proteostasis and perform a protective function under various stress conditions, such as high temperature, intoxication, inflammation, or tissue hypoxia, constitute a promising group of possible biochemical markers for obesity and cardiovascular diseases. HSP27 is involved in essential cellular processes occurring in conditions of obesity and its cardiometabolic complications; it has protective properties, and its secretion may indicate a cellular response to stress. HSP40 plays a controversial role in the pathogenesis of obesity. HSP60 is involved in various pathological processes of the cardiovascular, immune, excretory, and nervous systems and is associated with obesity and concomitant diseases. The hypersecretion of HSP60 is associated with poor prognosis; hence, this protein may become a target for further research on obesity and its cardiovascular complications. According to most studies, intracellular HSP70 is an obesity-promoting factor, whereas extracellular HSP70 exhibited inconsistent dynamics across different patient groups and diagnoses. HSPs are involved in the pathogenesis of cardiovascular pathology. However, in the context of cardiovascular and metabolic pathology, these proteins require further investigation.

Lipoprotein (a) and coronary artery calcification: prospective study assessing interactions with other risk factors

BACKGROUND

Elevated plasma lipoprotein (a) [Lp(a)] and coronary artery calcification (CAC) are established cardiovascular risk factors that correlate with each other. We hypothesized that other cardiovascular risk factors could affect their relationship.

METHODS

We tested for interactions of 24 study variables related to dyslipidemia, diabetes, insulin resistance, hypertension, inflammation and coagulation with baseline Lp(a) on change in CAC volume and density over 9.5 years in 5975 Multi-Ethnic Study of Atherosclerosis (MESA) participants, free of apparent cardiovascular disease at baseline.

RESULTS

Elevated Lp(a) was associated with larger absolute increase in CAC volume (3.21 and 4.45 mm3/year higher for Lp(a) ≥30 versus <30 mg/dL, and Lp(a) ≥50 versus <50 mg/dL, respectively), but not relative change in CAC volume. No association was found with change in CAC density when assessing continuous ln-transformed Lp(a). The association between elevated Lp(a) (≥30 mg/dL) and absolute change in CAC volume was greater in participants with higher circulating levels of interleukin-2 soluble receptor α, soluble tumor necrosis factor alpha receptor 1 and fibrinogen (15.33, 11.81 and 7.02 mm3/year in quartile 4, compared to -3.44, -0.59 and 1.91 mm3/year in quartile 1, respectively). No significant interaction was found for other study variables. Similar interactions were seen when assessing Lp(a) levels ≥50 mg/dL.

CONCLUSIONS

Elevated Lp(a) was associated with an absolute increase in CAC volume, especially in participants with higher levels of selected markers of inflammation and coagulation. These results suggest Lp(a) as a potential biomarker for CAC volume progression.

Heat shock protein 60 and cardiovascular diseases: An intricate love-hate story

Cardiovascular diseases (CVDs) are the result of complex pathophysiological processes in the tissues comprising the heart and blood vessels. Inflammation is the main culprit for the development of cardiovascular dysfunction, and it may be traced to cellular stress events including apoptosis, oxidative and shear stress, and cellular and humoral immune responses, all of which impair the system's structure and function. An intracellular chaperone, heat shock protein 60 (HSP60) is an intriguing example of a protein that may both be an ally and a foe for cardiovascular homeostasis; on one hand providing protection against cellular injury, and on the other triggering damaging responses through innate and adaptive immunity. In this review we will discuss the functions of HSP60 and its effects on cells and the immune system regulation, only to later address its implications in the development and progression of CVD. Lastly, we summarize the outcome of various studies targeting HSP60 as a potential therapeutic strategy for cardiovascular and other diseases.

Heat Shock Protein 60 Antibodies Are Associated With a Risk Factor for Cardiovascular Disease in Bedridden Elderly Patients

Frailty, in elderly people, represents multiple deficiencies in different organs and is characterized by decreased physiological reserves and greater vulnerability to stressors. Bedridden elderly, with cardiovascular disease (CVD), have a worse prognosis than non-bedridden patients. Heat-shock proteins (HSPs) are molecular chaperones that under physiological conditions facilitate the transport, folding and assembly of proteins. Serum HSP 60-kDa concentrations and their antibodies are increased, in response to non-physiological conditions, suggesting the involvement of HSPs and their antibodies in the development of CVD. The aim of this work was to evaluate heat shock protein 60 and anti-HSP60 antibody levels, associated with a risk factor for cardiovascular disease, in bedridden elderly patients. Clinical, analytical and cross-sectional analyses were performed with 57 elderly (>65 years). HSP60 and anti-HSP60 plasma levels were measured by ELISA. Bivariate analysis using a linear regression model adjusted for risk factors used Framingham Score. Among the 57 elderly, with an average age of 69.89 years, 39% are bedridden; 26% with pre-existing cardiovascular disease and 44% are dyslipidemic. The relationship of risk factors in the Framingham Score was positive for the anti-HSP60 antibody (p = 0.042) measurement. Our data show a positive correlation among the elevation of the Framingham score and the profile of anti-HSP60 antibodies. These results suggest a greater immune activation that is associated with cardiovascular risk and bedridden fragility.

Resveratrol ameliorates atherosclerosis induced by high-fat diet and LPS in ApoE-/- mice and inhibits the activation of CD4+ T cells

Background

Atherosclerosis (AS), which characterized with the accumulation of lipids on the vessel wall, is the pathological basis of many cardiovascular diseases (CVD) and seriously threatens human health. Resveratrol (RES) has been reported to be benefit for AS treatment. This research aimed to observe the effects of RES on AS induced by high-fat diet (HFD) and LPS in ApoE^-/- mice and investigate the underlying mechanism.

Methods

ApoE^-/- mice were fed with HFD companied with LPS to induce AS and RES was administrated for 20 weeks. Splenic CD4⁺ T cells were cultured and treated with anti-CD3/CD28 together with LPS, and RES was added. Serum lipids and the atherosclerotic areas of aortas were detected. The activation of CD4⁺ T cells were investigated both in vivo and in vitro and the expression of DNA methyltransferases (Dnmt) in CD4⁺ T cells were measured.

Results

In vivo, administration of RES prevented HFD and LPS induced dysfunction of serum lipids including TC (total cholesterol), TG (triglyceride), LDL-C (low density lipoprotein cholesterol) and HDL-C (high density lipoprotein cholesterol), ameliorated the thickened coronary artery wall and decreased the areas of atherosclerotic lesion on aortas. Besides, RES decreased the number of CD4⁺ T cells in peripheral blood, decreased the expression of CD25 and CD44, but not affected the expression of L-selectin (CD62L). In vitro, RES decreased the expression of Ki67, CD25 and CD44 in CD4⁺ T cells. Moreover, RES increased the secretion of IL-2, IL-10 and TGF-β1, decreased IL-6. In addition, RES decreased both the mRNA and protein level of Dnmt1 and Dnmt3b in CD4⁺ T cells.

Conclusion

These results indicated that RES ameliorated AS induced by HFD companied with LPS in ApoE^-/- mice, inhibited the proliferation and activation of CD4⁺ T cells and regulated the expression of Dnmt1 and Dnmt3b.

Relationship Between Carbohydrate Antigen 125 and Coronary Artery Calcification in Patients without Known Coronary Artery Disease

BACKGROUND This study was designed to investigate the association between serum carbohydrate antigen 125 (CA125) and coronary artery calcification (CAC) score in patients without known coronary artery disease. MATERIAL AND METHODS The study groups included 348 consecutive subjects with chest pain but without known coronary artery disease, and who underwent an estimation of CAC score in our hospital. RESULTS The clinical and laboratory characteristics of all subjects are presented according to serum CA125 concentrations tertiles. The CAC score was found to be increased in the tertiles (31.6 ±82.10, 73.3±125.6, 122.9±135.9 U/mL, p<0.001). Serum CA125 concentrations are increased in calcium-positive patients compared with calcium-negative ones (9.3±4.79 vs. 11.2±7.36, p=0.003). A positive correlation between serum CA125 and CAC score was observed (r=0.319, p<0.001) in all participants. Similarly, the serum concentrations of CA125 were found to be positively correlated with CAC score in both women and men (r=0.328, p<0.001; r=0.265, p=0.001, respectively). Multiple linear regression analysis results indicated that serum CA125 concentrations are independently related to CAC score in the study population (beta=0.173, p=0.001), and age, sex, diabetes mellitus, and high-sensitivity C-reactive protein (hs-CRP) were also associated with CAC score in multiple linear regression analysis. CONCLUSIONS Serum CA125 concentrations are correlated with CAC score in the population without known coronary artery disease, and serum CA125 may be considered as a marker to estimate CAC in the study population.

The relationship between smoking intensity and subclinical cardiovascular injury: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

Modern tobacco regulatory science requires an understanding of which biomarkers of cardiovascular injury are most sensitive to cigarette smoking exposure.

METHODS

We studied self-reported current smokers from the Multi-Ethnic Study of Atherosclerosis. Smoking intensity was defined by number of cigarettes/day and urinary cotinine levels. Subclinical cardiovascular injury was assessed using markers of inflammation [high-sensitivity C-reactive protein (hsCRP), interleukin 6 & 2 (IL-2 & IL-6), tumor necrosis factor alpha (TNF-α)], thrombosis (fibrinogen, D-dimer, homocysteine), myocardial injury (troponin T; TnT), endothelial damage (albumin: creatinine ratio), and vascular function [aortic & carotid distensibility, flow-mediated dilation (FMD)]. Biomarkers were modeled as absolute and percent change using multivariable-adjusted linear regression models adjusted for cardiovascular risk factors and smoking duration.

RESULTS

Among 843 current smokers, mean age was 58 (9) years, 53% were men, 39% were African American, mean number of cigarettes per day was 13 (10), and median smoking duration was 39 (15) years. Cigarette count was significantly associated with higher hsCRP, IL-6 and fibrinogen (β coefficients: 0.013, 0.011, 0.60 respectively), while ln-transformed cotinine was associated with the same biomarkers (β coefficients: 0.12, 0.04, 5.3 respectively) and inversely associated with aortic distensibility (β coefficient: -0.13). There was a limited association between smoking intensity and homocysteine, D-dimer, and albumin:creatinine ratio in partially adjusted models only, while there was no association with IL-2, TNF-α, carotid distensibility, FMD, or TnT in any model. In percent change analyses, relationships were strongest with hsCRP.

CONCLUSIONS

Smoking intensity was associated with early biomarkers of CVD, particularly, markers of systemic inflammation. Of these, hsCRP may be the most sensitive.

Lower levels of IL-4 and IL-10 influence lipodystrophy in HIV/AIDS patients under antiretroviral therapy

BACKGROUND

The role of interleukins in the pathogenesis of lipodystrophy in HIV/AIDS-patients is still not understood. The aim of this study was to evaluate the relationship between serum levels of interleukins between HIV/AIDS-patients with or without lipodystrophy, as well as between different subgroups of lipodystrophy (lipoatrophy, lipohypertrophy, mixed-fat-redistribution) and patients without lipodystrophy.

METHODS

Cross-sectional study of 66 HIV/AIDS patients, all Caucasians. Serum levels of interleukins (IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10) were measured using Cytokine-Array-1 on Evidence Investigator, Biochip Array Technology. The associations between interleukins and anthropometric and metabolic variables were estimated by Spearman-correlation. Analysis of covariance with bootstrapping method (ACBM) was used to examine relationship between interleukins and lipodystrophy categories adjusted for confounding variables.

RESULTS

The lipodystrophy was observed in 29 (44%) patients, while 15 (52%) had lipoatrophy, 4 (14%) lipohypertrophy and 10 (34%) patients had mixed fat redistribution. There were 37 (56%) patients without lipodystrophy. Significantly lower levels of IL-4 and IL-10 were observed in lipodystrophy vs. non-lipodystrophy (p=0.008; p=0.027, respectively). No differences were found relating IL-1α, IL-1β, IL-2, IL-6 and IL-8 levels in lipodystrophy vs. non-lipodystrophy. In patient subgroup with lipoatrophy, significantly lower levels of IL-4 and IL-10 were found when compared to non-lipodystrophy (p=0.043; p=0.031, respectively). In lipohypertrophy subgroup significantly lower levels of IL-4 were found when compared to non-lipodystrophy (p=0.003). In order to estimate the correlation of IL-4 and IL-10 and the presence of lipodystrophy, ACBM showed that correlation of IL-4 levels in patients with lipodystrophy remains statistically significant (p=0.004) in all types of lipodystrophy: lipoatrophy, lipohypertrophy and mix-fat-redistribution (p=0.027; p=0.009; p=0.017, respectively) after adjustment for age, BMI.

CONCLUSIONS

IL-4 and IL-10 levels were significantly lower in lipodystrophy vs. non-lipodystrophy. According to our knowledge, we showed for the first time significant correlation between IL-4 levels and lipodystrophy development in HIV/AIDS patients.

Association between Heat Shock Protein-60 and Development of Atrial Fibrillation: Results from the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

During atrial fibrillation (AF), a high rate of myocyte activation causes cellular stress and initiates the process of atrial remodeling, which further promotes persistence of AF. Although heat shock proteins (HSPs) have been shown to prevent atrial remodeling and suppress the occurrence of AF in cellular and animal experimental models, increased levels of HSP-60 have been observed in patients with postoperative AF, likely reflecting a response to cellular stress. To better understand the role of HSP-60 in relation to AF, we examined the association of HSP-60 levels in relation to the future development of AF in the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS

MESA is a cohort study that recruited 6,814 participants aged 45-84 years and free of known cardiovascular disease at baseline (2000-2002) from six field centers. We investigated 983 participants, selected at random from the total cohort, who had HSP-60 measured and were free of AF at baseline. We tested the association of HSP-60 levels with the incidence of AF using multivariate Cox models after adjustment for demographics, clinical characteristics, and biomarkers.

RESULTS

During an average of 10.6 years of follow-up, 77 participants developed AF. We did not observe a significant association between the log-transformed HSP-60 levels and development of AF on either unadjusted or multivariate analysis (adjusted hazard ratio: 1.02 per unit difference on natural log scale, 95% confidence interval: 0.77-1.34 ln (ng/mL).

CONCLUSION

Contrary to the findings from the preclinical studies, which demonstrated an important role of HSP-60 in the pathogenesis of AF, we did not observe a significant association between HSP-60 and occurrence of AF.

Novel biomarkers of coronary microvascular disease

Coronary microvascular disease in the absence of myocardial diseases has traditionally been diagnosed through coronary reactivity testing in the cardiac catheterization laboratory. Compared with invasive procedures, blood-based biomarkers may have reduced cost, less risk of physical harm and greater accessibility, making them ideal for an outpatient management strategy. There are a variety of biomarkers available with potential utility in the management of microvascular disease; however, none have yet been extensively validated or established in this clinical patient population.

The cellular composition of the human immune system is shaped by age and cohabitation

Detailed population-level description of the human immune system has recently become achievable. We used a 'systems-level' approach to establish a resource of cellular immune profiles of 670 healthy individuals. We report a high level of interindividual variation, with low longitudinal variation, at the level of cellular subset composition of the immune system. Despite the profound effects of antigen exposure on individual antigen-specific clones, the cellular subset structure proved highly elastic, with transient vaccination-induced changes followed by a return to the individual's unique baseline. Notably, the largest influence on immunological variation identified was cohabitation, with 50% less immunological variation between individuals who share an environment (as parents) than between people in the wider population. These results identify local environmental conditions as a key factor in shaping the human immune system.