Association between inflammation, lipid and hemostatic factors in patients with stable angina

Relationship between human serum metabolites and angina pectoris: a Mendelian randomization study

PURPOSE

We aimed to explore the causal relationship between human serum metabolites and angina pectoris.

METHODS

This study used two-sample Mendelian randomization (MR) analysis to assess the association between 486 serum metabolites and angina pectoris. The analytical methods employed to reduce study bias included inverse variance weighted, MR-Egger, and weighted median method. A comprehensive sensitivity analysis was performed using the leave-one-out method, while instrumental variable pleiotropy was tested with MR-Pleiotropy RESidual Sum and Outlier. Metabolic pathways of angina-associated metabolites were analysed on the MetaboAnalyst metabolomics analysis tool platform.

RESULTS

In this study, 42 serum metabolites were found to be strongly associated with angina pectoris. They mainly belonged to seven groups: amino acids, carbohydrates, cofactors and vitamins, lipids, nucleotides, unknown metabolites, and exogenous substances. Pipecolate posed the highest risk for the development of angina pectoris among the 42 serum metabolites. The main metabolic pathways associated with angina pectoris were glycine, serine, threonine metabolism, primary bile acid biosynthesis, and caffeine metabolism.

CONCLUSION

We identified 25 high-risk and 17 protective human serum metabolites associated with angina pectoris. Their associated major metabolic pathways were also determined. The serum metabolite pipecolate was significantly and positively correlated with the risk of angina pectoris. This finding may serve as a valuable reference for testing serum markers associated with angina pectoris.

The emerging role of fibrin(ogen) in cardiovascular disease

OBJECTIVE

A coagulation factor called fibrinogen is produced by the liver and is proteolyzed by thrombin to become fibrin. The latest studies have revealed that fibrin(ogen) palys an essential role in the regulation of cardiovascular disease. Understanding the relationship and mechanism between fibrin(ogen) and cardiovascular disease is of great significance for maintaining overall health. The objective of this review is to discuss the specific involvement and underlying mechanisms of fibrin(ogen) in cardiovascular disease.

METHODS

A review was conducted using the PubMed database to identify and analyze the emerging role of fibrinogen in cardiovascular disease.

RESULTS

The literature review revealed that fibrin(ogen) plays a pivotal role in maintaining cardiovascular disease and are involved in the pathogenesis of cardiovascular disease. Fibrin(ogen) mainly influence various pathophysiological processes, such as participating in thrombosis formation, stimulating the inflammatory response, and other molecular pathways.

CONCLUSION

This review focuses on the involvement of fibrin(ogen) in cardiovascular disease, with a particular emphasis on the main functions and underlying mechanisms by which fibrin(ogen) influence the pathogenesis and progression of these conditions. This review underscores the potential of fibrin(ogen) as therapeutic targets in managing cardiovascular disease.

Association of Apolipoprotein A1, High Density Lipoprotein Cholesterol, and Their Ratio with Inflammatory Marker in Chinese Adults with Coronary Artery Disease

Sparse data assessed the association of apolipoprotein A1 (ApoA1) and high density lipoprotein cholesterol (HDL-C) with inflammation. We investigated this association in a hospital-based cross-sectional pilot study that included 7296 patients with coronary artery disease (CAD). In multivariate analysis, negative associations of ApoA1 and HDL-C with C-reactive protein (CRP), high sensitivity CRP (hsCRP), and tumor necrosis factor-α (TNF-α) were shown. The corresponding CRP, hsCRP, and TNF-α values were 5.28 (vs 11.70 mg/L), 4.50 (vs 11.50 mg/L), and 7.68 (vs 10.90 pg/mL) for ApoA1, and 7.13 (vs 10.60 mg/L), 6.27 (vs 9.19 mg/L), and 8.11 (vs 11.86 pg/mL) for HDL-C in the fourth quartiles compared with the first quartiles. ApoA1/HDL-C ratio was inversely associated with hsCRP and interleukin-6 (IL-6). No significant associations of ApoA1 and HDL-C with IL-6 and IL-8, and of ApoA1/HDL-C ratio with CRP, IL-8, and TNF-α were observed. In path analyses, there was no evidence of mediating effects of body mass index on the "ApoA1 and HDL-C-inflammation" relationship. Generally, our study of CAD patients identified graded and inverse associations of ApoA1, HDL-C, and ApoA1/HDL-C ratio with inflammatory marker (CRP, hsCRP, IL-6, IL-8, or TNF-α) levels.

Lipoprotein(a)—The Crossroads of Atherosclerosis, Atherothrombosis and Inflammation

Increased lipoprotein(a) (Lp(a)) levels are an independent predictor of coronary artery disease (CAD), degenerative aortic stenosis (DAS), and heart failure independent of CAD and DAS. Lp(a) levels are genetically determinated in an autosomal dominant mode, with great intra- and inter-ethnic diversity. Most variations in Lp(a) levels arise from genetic variations of the gene that encodes the apolipoprotein(a) component of Lp(a), the LPA gene. LPA is located on the long arm of chromosome 6, within region 6q2.6–2.7. Lp(a) levels increase cardiovascular risk through several unrelated mechanisms. Lp(a) quantitatively carries all of the atherogenic risk of low-density lipoprotein cholesterol, although it is even more prone to oxidation and penetration through endothelia to promote the production of foam cells. The thrombogenic properties of Lp(a) result from the homology between apolipoprotein(a) and plasminogen, which compete for the same binding sites on endothelial cells to inhibit fibrinolysis and promote intravascular thrombosis. LPA has up to 70% homology with the human plasminogen gene. Oxidized phospholipids promote differentiation of pro-inflammatory macrophages that secrete pro-inflammatory cytokines (e. g., interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α). The aim of this review is to define which of these mechanisms of Lp(a) is predominant in different groups of patients.

Prognostic Value of Baseline d-Dimer Level in Patients With Coronary Artery Disease: A Meta-Analysis

The prognostic significance of d-dimer level in patients with coronary artery disease (CAD) is not fully established. This meta-analysis aimed to examine the association between elevated d-dimer level at baseline and adverse outcomes in patients with CAD. Two independent authors comprehensively searched PubMed and Embase databases from their inception to December 31, 2020. All observational studies reporting the values of baseline d-dimer level in predicting the major adverse cardiovascular events (MACEs) or survival outcomes in patients with CAD were included. The prognostic values were calculated by pooling adjusted RR with 95% CI for the highest versus the lowest d-dimer level. Thirteen studies consisting of 25 600 patients with CAD were identified. Comparison between the highest and lowest d-dimer level showed that the pooled multivariable adjusted RR was 1.69 (95% CI, 1.53-1.86) for all-cause mortality, 2.37 (95% CI, 1.52-3.69) for cardiovascular mortality, and 1.44 (95% CI, 1.19-1.74) for MACEs, respectively. Elevated blood level of d-dimer at baseline was independently associated with higher risk of MACEs, cardiovascular death, and all-cause mortality in patients with CAD. The baseline d-dimer level may have important prognostic value in patients with CAD.

[Clinical significance of hypersensitive C-reactive protein, fribrinogen and D-dimmer in connective tissue disease-related interstitial lung disease]

OBJECTIVE

To investigate the clinical significance of plasma levels of hypersensitive C-reactive protein (hs-CRP), fibriogen and D-dimmer (D-DI) in patients with connective tissue disease (CTD)-related interstitial lung disease (CTD-ILD).

METHODS

Sixty-nine patients with interstitial lung disease admitted in Zhujiang Hospital between January, 2010 and April, 2016, including 29 with CTD-ILD and 40 with non-CTD-ILD were analyzed for plasma levels of hs-CRP, fibriogen and D-DI, with 25 healthy subjects as the control group.

RESULTS

The plasma level of hs-CRP, fibriogen and D-DI in patients with CTD-ILD and non-CTD-ILD were all significantly higher than those in the control group. The patients with CTD-ILD had a significantly higher hs-CRP level than those with non-CTD-ILD, but the levels of fibriogen and D-DI were comparable between the two groups. Correlation analysis indicated that Hs-CRP level was positively correlated with the levels of D-DI (r=0.539, P<0.01) and fibrinogen (r=0.534, P<0.01).

CONCLUSION

Hs-CRP, fibriogen and D-DI levels show an important value in clinical diagnosis of CTD, and an obvious elevation of hs-CRP is correlated with the CTD.

Pregnancy as a Window to Future Cardiovascular Health: Design and Implementation of the nuMoM2b Heart Health Study

The National Institute of Child Health and Human Development's Nulliparous Pregnancy Outcomes Study-Monitoring Mothers-to-Be (nuMoM2b) Heart Health Study (HHS) was designed to investigate the relationships between adverse pregnancy outcomes and modifiable risk factors for cardiovascular disease. The ongoing nuMoM2b-HHS, which started in 2013, is a prospective follow-up of the nuMoM2b cohort, which included 10,038 women recruited between 2010 and 2013 from 8 centers across the United States who were initially observed over the course of their first pregnancies. In this report, we detail the design and study procedures of the nuMoM2b-HHS. Women in the pregnancy cohort who consented to be contacted for participation in future studies were approached at 6-month intervals to ascertain health information and to maintain ongoing contact. Two to 5 years after completion of the pregnancy documented in the nuMoM2b, women in the nuMoM2b-HHS were invited to an in-person study visit. During this visit, they completed psychosocial and medical history questionnaires and had clinical measurements and biological specimens obtained. A subcohort of participants who had objective assessments of sleep-disordered breathing during pregnancy were asked to repeat this investigation. This unique prospective observational study includes a large, geographically and ethnically diverse cohort, rich depth of phenotypic information about adverse pregnancy outcomes, and clinical data and biospecimens from early in the index pregnancy onward. Data obtained from this cohort will provide mechanistic and clinical insights into how data on a first pregnancy can provide information about the potential development of subsequent risk factors for cardiovascular disease.

Apolipoprotein polymorphism is associated with pro-thrombotic profile in non-demented dyslipidemic subjects

Apolipoprotein gene polymorphism has an important role in lipid metabolism and in the development of cerebro- and cardio-vascular disease (CCVD), including dementia. Dyslipidemia and hemostatic abnormalities are key risk factors associated with athero-sclerotic events preceding CCVD. The aim of this study was to evaluate the possible relationships of various apolipoprotein-species with hemostatic parameters and cognitive function. Lipid profile, gene polymorphism, coagulation markers, and mini-mental state examination (MMSE) scores were assessed in 109 dys-lipidemic subjects and in 107 healthy control volunteers. Thrombin-activatable fibrinolysis inhibitor (TAFI) plasma levels were significantly higher in apolipoprotein-E2 (apoE2) patients when compared to other apoE forms. The apoA5 -1131T>C polymorphism was associated with elevated D-dimer concentration in dyslipidemic TT homozygous individuals. MMSE did not correlate with lipid or coagulation profile. These data suggest that apoE and apoA5 variants have an effect on hemostatic parameters, but they neither influence nor predict cognitive performance in non-demented individuals.

Circulatory syndrome: an evolution of the metabolic syndrome concept!

The metabolic syndrome has been a useful, though controversial construct in clinical practice as well as a valuable model in order to understand the interactions of diverse cardiovascular risk factors. However the increasing importance of the circulatory system in particular the endothelium, in both connecting and controlling organ function has underlined the limitations of the metabolic syndrome definition. The proposed "Circulatory Syndrome" is an attempt to refine the metabolic syndrome concept by the addition of recently documented markers of cardiovascular disease including renal impairment, microalbuminuria, arterial stiffness, ventricular dysfunction and anaemia to more classic factors including hypertension, dyslipidemia and abnormal glucose metabolism; all of which easily measured in clinical practice. These markers interact with each other as well as with other factors such as aging, obesity, physical inactivity, diet and smoking. The final common pathways of inflammation, oxidative stress and hypercoagulability thereby lead to endothelial damage and eventually cardiovascular disease. Nevertheless, the Circulatory (MARC) Syndrome, like its predecessor the metabolic syndrome, is only a small step toward an understanding of these complex and as yet poorly understood markers of disease.

The many faces of the octahedral ferritin protein

Iron is an essential trace nutrient required for the active sites of many enzymes, electron transfer and oxygen transport proteins. In contrast, to its important biological roles, iron is a catalyst for reactive oxygen species (ROS). Organisms must acquire iron but must protect against oxidative damage. Biology has evolved siderophores, hormones, membrane transporters, and iron transport and storage proteins to acquire sufficient iron but maintain iron levels at safe concentrations that prevent iron from catalyzing the formation of ROS. Ferritin is an important hub for iron metabolism because it sequesters iron during times of iron excess and releases iron during iron paucity. Ferritin is expressed in response to oxidative stress and is secreted into the extracellular matrix and into the serum. The iron sequestering ability of ferritin is believed to be the source of the anti-oxidant properties of ferritin. In fact, ferritin has been used as a biomarker for disease because it is synthesized in response to oxidative damage and inflammation. The function of serum ferritin is poorly understood, however serum ferritin concentrations seem to correlate with total iron stores. Under certain conditions, ferritin is also associated with pro-oxidant activity. The source of this switch from anti-oxidant to pro-oxidant has not been established but may be associated with unregulated iron release from ferritin. Recent reports demonstrate that ferritin is involved in other aspects of biology such as cell activation, development, immunity and angiogenesis. This review examines ferritin expression and secretion in correlation with anti-oxidant activity and with respect to these new functions. In addition, conditions that lead to pro-oxidant conditions are considered.

Activation of the fibrinolytic cascade early in pregnancy among women with spontaneous preterm birth

OBJECTIVE

To evaluate the association of early pregnancy concentrations of thrombin-antithrombin III complex with subsequent spontaneous preterm birth.

METHODS

In a nested case-control study, thrombin-antithrombin III complex was measured in plasma before 20 weeks of gestation (mean 9.9 weeks) among women without chronic conditions, preeclampsia, or growth restriction. C-reactive protein and non-high-density lipoprotein cholesterol were also measured. Women with spontaneous preterm birth before 34 weeks of gestation (n=29) and 34 weeks to 36 weeks of gestation (n=72) were compared with women with term births occurring at or after 37 weeks (n=219). Polychotomous logistic regression was used to relate elevated thrombin-antithrombin III complex (greater than 5.5 ng/mL), dyslipidemia (non-high-density lipoprotein cholesterol greater than the 90th percentile), and inflammation (C-reactive protein at or above 8 micrograms/mL) to risk of spontaneous preterm birth subtypes.

RESULTS

Women with spontaneous preterm birth compared with term births had elevated thrombin-antithrombin III complex (P=.02), and they were more likely to have a thrombin-antithrombin III complex greater than 5.5 ng/mL (P<.01). Women with thrombin-antithrombin III complex in the highest compared with lowest quartile had a 4.6-fold (95% confidence interval 1.3-15.8) increased risk for spontaneous preterm birth before 34 weeks of gestation, adjusted for body mass index, race, inflammation, dyslipidemia, and gestational age at sampling. There was a dose-response trend between thrombin-antithrombin III complex and spontaneous preterm birth before 34 weeks (P<.01) and 34 to 36 weeks (P=.03).

CONCLUSION

There is evidence of early pregnancy systemic fibrinolysis among women with spontaneous preterm birth before 34 weeks of gestation independent of inflammation and dyslipidemia, perhaps secondary to microvascular injury.

LEVEL OF EVIDENCE

II.

Fibrinogen decreases cardiomyocyte contractility through an ICAM-1-dependent mechanism

Introduction

Cardiomyocytes exposed to inflammatory processes express intracellular adhesion molecule-1 (ICAM-1). We investigated whether fibrinogen and fibrinogen degradation products, including D-dimer, could alter cardiomyocyte contractile function through interaction with ICAM-1 found on inflamed cardiomyocytes.

Methods

In vivo, rats were injected with endotoxin to model systemic inflammation, whereas isolated rat cardiomyocytes were treated with tumor necrosis factor-alpha to model the inflammatory environment seen following exposure to bacterial products such as lipopolysaccharide.

Results

In vivo, endotoxin administration profoundly decreased cardiac contractile function associated with a large increase in intracardiac ICAM-1 and perivascular fibrinogen. Confocal microscopy with double-staining of isolated rat cardiomyocytes demonstrated colocalization of ICAM-1 and fibrinogen. This interaction was disrupted through pre-treatment of the cells with an ICAM-1-blocking antibody. Functionally, isolated rat cardiomyocyte preparations exhibited decreased fractional shortening when incubated with fibrinogen, and through the use of synthetic peptides, we determined that residues 117–133 of the fibrinogen gamma chain are responsible for this interaction with ICAM-1. Despite having crosslinked gamma chains, D-dimer retained the ability to decrease cardiomyocyte contractility.

Conclusion

Site 117–133 of the fibrinogen gamma chain is able to depress cardiomyocyte contractility through binding ICAM-1.