Endothelial Markers in Type 2 Diabetic Patients with Acute Decompensated Heart Failure: A Pilot Study

BACKGROUND

Impaired endothelial function has been associated with vascular complications in type 2 diabetes (T2D), but its role in T2D-related heart failure (HF) remains indeterminate. The aim of this study was to assess selected markers of endothelial function in T2D patients with acute decompensated HF.

METHODS

A pilot prospective study on patients with acute decompensated HF requiring in-hospital admission was carried out. The vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1), and vascular cell adhesion molecule 1 (VCAM-1) were assessed at admission and after decongestion. Subsequently, differences in these markers between T2D and non-diabetic (ND) patients were studied.

RESULTS

In total, 39 patients (21 with T2D and 18 ND patients) were enrolled. Twenty-eight patients presented with preserved ejection fraction (EF), and 11 presented with reduced EF. Looking at the VEGF levels in T2D patients, on admission, a median of 233.0 pg/mL (1.7-598 pg/mL) was found compared to 106.0 pg/mL (1.7-888 pg/mL) in ND individuals; the differences reached statistical significance (p = 0.04). There were no significant differences in VEGF levels after decongestion, and in VCAM-1 (2237 ± 1195 vs. 2699 ± 1093 ng/mL, p = 0.37) and ICAM-1 (596 ± 268 vs. 638 ± 437 ng/mL, p = 0.79) levels between T2D and ND patients upon admission and after decongestion. The value of EF (preserved or reduced) affected the VEGF levels upon admission.

CONCLUSIONS

This study identified significantly higher VEGF levels upon admission due to acute decompensated HF in T2D patients.

Persistently elevated sFlt-1 and recovery of reduced ADAMTS13 activity in malignant hypertension

BACKGROUND AND OBJECTIVES

Malignant hypertension (MHT) characterized by acute hypertension with retinopathy or multiorgan damage, is a severe form of hypertensive emergency and associated with target organ involvement and poor kidney outcome. However, the underlying mechanisms are unclear.

METHODS

Eighty-four patients with acute severe hypertension from the Nephrology Department and Emergency Department in a single center during January 2016 and December 2017 were prospectively enrolled and divided into MHT ( n  = 48) and non-MHT ( n  = 36) subgroups according to target organ evaluation. Forty healthy controls were recruited. Serum soluble Fms-like tyrosine kinase-1 (sFlt-1) levels and plasma ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 motif, member 13) activity were examined at baseline and 12-month follow-up. Renal endpoints were defined as a significant decrease in the estimated glomerular filtration rate (eGFR) of more than 40% or the occurrence of end-stage renal disease.

RESULTS

Serum sFlt-1 levels were persistently elevated in MHT. Baseline serum sFLT-1 levels were correlated with plasma ADAMTS13 activity and markers of target organ damage. Plasma ADAMTS13 activity was reduced in both MHT and non-MHT patients and recovered to the normal range at 12-month follow-up. During an average follow-up time of 53 ± 13 months, the restoration of reduced ADAMTS13 activity was correlated with the improvement of kidney function and independently reduced the risk of renal endpoints.

CONCLUSIONS

Abnormal angiogenesis and endothelial damage are involved in the pathophysiology of hypertensive emergency. Evaluation of ADAMTS13 and sFlt-1 may help in the diagnosis and assessment of MHT. Recovery of ADAMTS13 predicts better renal outcome in patients with hypertensive emergencies.

Serum VEGF: Diagnostic Value of Acute Coronary Syndrome from Stable Angina Pectoris and Prognostic Value of Coronary Artery Disease

Background

Although the level of serum vascular endothelial growth factor (VEGF) is elevated in coronary artery disease (CAD) patients, its potential role in acute coronary syndrome (ACS) or stable angina pectoris (SAP) patients remains unclear.

Objectives

To evaluate diagnostic accuracy of serum VEGF in determining ACS patients from SAP and analyze the association of serum VEGF with coronary artery lesions in SAP or the GRACE score in ACS, which is involved in the poor prognosis of low serum VEGF.

Methods

248 CAD patients and 48 healthy subjects were enrolled in this study. Serum VEGF levels were detected by using ELISA. The Gensini score or GRACE score was calculated among SAP or ACS patients. All the patients were followed up for a period of 12 months (mean: 10.77 months).

Results

VEGF serum concentrations were higher in the ACS subgroup than in the SAP subgroup (P < 0.001) with diagnostic accuracy of ACS from SAP (AUC: 0.667, sensitivity: 68.5%, specificity: 60.1%, P < 0.001). Patients with high risk of Gensini score showed reduced VEGF levels (P < 0.001) accompanied by a negative correlation (r = -0.396, P < 0.001). Patients with a higher GRACE score indicated lower VEGF levels (P < 0.001). Low serum VEGF was one of the potential risk factors with adjusted HR of 0.531 (P=0.048).

Conclusion

Serum VEGF exhibits efficient diagnostic value for detection of ACS from SAP with a cutoff value of 648.75 pg/mL. Low serum VEGF indicates severe coronary artery lesions and a higher GRACE score, which suggests poor clinical outcomes.

Placenta growth factor and sFlt-1 as biomarkers in ischemic heart disease and heart failure: a review

Coronary heart disease (CHD) and heart failure (HF) produce significant morbidity/mortality but identifying new biomarkers could help in the management of each. In this article, we summarize the molecular regulation and biomarker potential of PIGF and sFlt-1 in CHD and HF. PlGF is elevated during ischemia and some studies have shown PlGF, sFlt-1 or PlGF:sFlt-1 ratio, when used in combination with standard biomarkers, strengthens predictions of outcomes. sFlt-1 and PlGF are elevated in HF with sFlt-1 as a stronger predictor of outcomes. Although promising, we discuss additional study criteria needed to confirm the clinical usefulness of PlGF or sFlt-1 in the detection and management of CHD or HF.

Increased soluble fms-like tyrosine kinase 1 after ischemia reperfusion contributes to adverse clinical outcomes following kidney transplantation

Renal ischemia reperfusion injury (IRI) adversely affects clinical outcomes following kidney transplantation. Understanding the cellular mechanisms and the changes in gene/protein expression following IRI may help to improve these outcomes. Serum soluble fms-like tyrosine kinase 1 (sFlt-1), a circulating antiangiogenic protein, is increased in the first week following kidney transplantation. We evaluated the casual relationship of elevated sFlt-1 levels with renal microvascular dysfunction following IRI in a longitudinal study of 93 kidney transplant recipients and in several animal models. Transplant recipients with higher sFlt-1 levels had higher odds of delayed graft function, graft rejection, impaired graft function, and death. In a subgroup of 25 participants who underwent kidney biopsy within 4 months of kidney transplantation, peritubular capillary area was lower in those with elevated serum sFtl-1 levels. The administration of recombinant sFlt-1 into rodents resulted in significant structural and functional changes of the renal microvasculature, including reduced peritubular capillary density and intracapillary blood volume, and lead to increased expression of inflammatory genes and increased fibrosis. In a murine model of IRI, the kidney was a site of sFlt-1 production, and systemic neutralization of sFlt-1 preserved peritubular capillary density and alleviated renal fibrosis. Our data indicate that high sFlt-1 levels after IRI play an important role in the pathogenesis of microvascular dysfunction, thereby contributing to adverse clinical outcomes following kidney transplantation.

Endothelial cell markers from clinician's perspective

Endothelial cell markers are membrane-bound or cytoplasmic molecules expressed by endothelial cells, which help their easier identification and discrimination from other cell types. During vasculogenesis, endothelial cells differentiate from hemangioblasts to form new blood vessels. With the discovery of endothelial progenitor cells (EPC) and their ability to form new blood vessels, the term vasculogenesis is not only reserved for the embryonic development. Possibility of de novo blood vessel formation from EPC is now widely explored in different ischemic conditions, especially in cardiovascular medicine. Numerous clinical trials have tested enhancing tissue vascularization by delivering hematopoietic cells that expressed endothelial markers. This therapeutic approach proved to be challenging and promising, particularly for patients who have exhausted all conventional therapeutic modalities. Angiogenesis, which refers to the formation of new blood vessels from existing vasculature, is indispensable process during tumor progression and metastasis. Blockage of tumor angiogenesis by targeting and inhibiting endothelial cell has emerged as novel safe and efficacious method to control many advanced malignant diseases. Numerous clinical studies are currently testing new antiangiogenic drugs which target and inhibit endothelial cell markers, receptors or molecules which transmit receptor-mediated signals, therefore inhibiting endothelial cell proliferation, migration and vascular tube formation. Many of these drugs are now widely used in clinical settings as first- or second-line chemotherapy in advanced malignant conditions. So far, these therapeutic approaches gave modest, yet encouraging clinical improvements, prolonging survival and improving functional capacity and quality of life for many terminally ill patients. Here we present the most commonly used endothelial cell markers along with their applicability in contemporary clinical practice.

Serum VEGF Predicts Worse Clinical Outcome of Patients with Coronary Heart Disease After Percutaneous Coronary Intervention Therapy

Background

Percutaneous coronary intervention (PCI) is an effective treatment for coronary heart disease (CHD) patients. However, patients after PCI treatment often have ischemic events that result in poor prognosis. Our study aimed to investigate the effects of vascular endothelial growth factor (VEGF) level on the prognosis of CHD patients.

Material/Methods

We enrolled 114 CHD patients in the study. Serum VEGF level was measured by enzyme-linked immunosorbent assay (ELISA). Total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, and Hs-CRP were also tested in patients. The patients were divided into 2 groups according to the level of VEGF. Kaplan-Meier curve was used to observe the differences in survival situation of patients of the 2 groups. Cox regression analysis was conducted to judge whether VEGF was an independent biomarker for prognosis in CHD.

Results

We included 104 patients for survival analysis. VEGF level in CHD patients was significantly lower than that of healthy individuals (P<0.05). In the analysis of basic information, we found differences in sex distribution and hypertension between groups (P<0.05 for both). Kaplan-Meier curve indicated that patients with low expression of VEGF presented with poor prognosis. The mortality rate of the low-expression group was 37.71%, higher than that of the high-expression group (14.3%). Cox analysis suggested that VEGF could serve as a biomarker for prognosis in CHD (HR: 3.014, P: 0.019).

Conclusions

Low level of VEGF may predict poor clinical outcome of CHD patients after PCI treatment.

Circulating endothelial cell number and markers of endothelial dysfunction in previously preeclamptic women

OBJECTIVE

Patients with preeclampsia (PE) have endothelial dysfunction and an increased future risk of cardiovascular (CV) mortality. The number of circulating endothelial cells (CECs) is markedly increased in conditions associated with a high degree of endothelial cell activation/injury including PE. We hypothesized that the number of CECs continues to be increased in women with a history of PE, reflecting ongoing endothelial cell activation/injury.

STUDY DESIGN

CECs, flow-mediated vasodilation, levels of adhesion molecules and soluble vascular endothelial growth factor receptor-1 (sVEGFR1), and urine albumin/creatinine ratio were determined in 21 healthy women with ongoing normal pregnancy, 24 healthy currently nonpregnant women with a history of normal pregnancy, a total of 17 women with currently active mild (n = 11) or severe (n = 6) PE without hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome, and 16 currently nonpregnant women with a history of mild (n = 10) or severe (n = 6) PE.

RESULTS

Blood samples from women with active preeclampsia had higher CECs (9.9 ± 7.9 cells/mL) than healthy pregnant women (3.0 ± 4.1 cells/mL; P < .001), healthy nonpregnant women with a history of normal pregnancy (3.4 ± 4.0 cells/mL; P < .001), or women with a history of preeclampsia (2.4 ± 2.0 cells/mL; P < .001). The number of CECs were similar between women with a history of preeclampsia and healthy nonpregnant women with a history of normal pregnancy. Patients with active preeclampsia had significantly higher soluble vascular cell adhesion molecule-1, soluble E-selectin, sVEGFR1, and urinary albumin/creatinine ratio than healthy pregnant women. However, soluble vascular cell adhesion molecule-1, soluble E-selectin, urinary albumin/creatinine ratio were similar in women with a history of preeclampsia and healthy nonpregnant women with a history of normal pregnancy. However, women with a history of preeclampsia had higher sVEGFR1 levels than women with a history of normal pregnancy (P < .05).

CONCLUSION

Markers of endothelial activation, dysfunction, and damage were increased in patients with PE. After the delivery, this activation status is similar to the age-matched nonpregnant women with a history of normal pregnancy. However, sVEGFR-1 levels remain higher in women with a history of preeclampsia compared with women without a history of preeclampsia.

Soluble Flt-1 links microvascular disease with heart failure in CKD

Chronic kidney disease (CKD) is associated with an increased risk of heart failure (HF). Elevated plasma concentrations of soluble Flt-1 (sFlt-1) have been linked to cardiovascular disease in CKD patients, but whether sFlt-1 contributes to HF in CKD is still unknown. To provide evidence that concludes a pathophysiological role of sFlt-1 in CKD-associated HF, we measured plasma sFlt-1 concentrations in 586 patients with angiographically documented coronary artery disease and renal function classified according to estimated glomerular filtration rate (eGFR). sFlt-1 concentrations correlated negatively with eGFR and were associated with signs of heart failure, based on New York Heart Association functional class and reduced left ventricular ejection fraction (LVEF), and early mortality. Additionally, rats treated with recombinant sFlt-1 showed a 15 % reduction in LVEF and a 29 % reduction in cardiac output compared with control rats. High sFlt-1 concentrations were associated with a 15 % reduction in heart capillary density (number of vessels/cardiomyocyte) and a 24 % reduction in myocardial blood volume. Electron microscopy and histological analysis revealed mitochondrial damage and interstitial fibrosis in the hearts of sFlt-1-treated, but not control rats. In 5/6-nephrectomised rats, an animal model of CKD, sFlt-1 antagonism with recombinant VEGF121 preserved heart microvasculature and significantly improved heart function. Overall, these findings suggest that a component of cardiovascular risk in CKD patients could be directly attributed to sFlt-1. Assessment of patients with CKD confirmed that sFlt-1 concentrations were inversely correlated with renal function, while studies in rats suggested that sFlt-1 may link microvascular disease with HF in CKD.

Prognostic value of VEGF in patients submitted to percutaneous coronary intervention

We examined the longitudinal changes of VEGF levels after percutaneous coronary intervention for predicting major adverse cardiac events (MACE) in coronary artery disease (CAD) patients. VEGF was measured in 94 CAD patients' serum before revascularization, 1-month and 1-year after. Independently of clinical presentation, patients had lower VEGF concentration than a cohort of healthy subjects (median, IQ: 15.9, 9.0–264 pg/mL versus 419, 212–758 pg/mL; P < 0.001) at baseline. VEGF increased to 1-month (median, IQ: 276, 167–498 pg/mL; P < 0.001) and remained steady to 1-year (median, IQ: 320, 173–497 pg/mL; P < 0.001) approaching control levels. Drug eluting stent apposition and previous medication intake produced a less steep VEGF evolution after intervention (P < 0.05). Baseline VEGF concentration <40.8 pg/mL conveyed increased risk for MACE in a 5-year follow-up. Results reflect a positive role of VEGF in recovery and support its importance in CAD prognosis.

Circulating angiogenic biomolecules at rest and in response to upper-limb exercise in individuals with spinal cord injury

OBJECTIVE

Individuals with spinal cord injury (SCI) show structural and functional vascular maladaptations and muscle loss in their lower limbs. Angiogenic biomolecules play important roles in physiological and pathological angiogenesis, and are implicated in the maintenance of muscle mass. This study examined the responses of angiogenic molecules during upper-limb aerobic exercise in patients with SCI and in able-bodied (AB) individuals.

METHODS

Eight SCI patients with thoracic lesions (T6-T12, ASIA A) and eight AB individuals performed an arm-cranking exercise for 30 minutes at 60% of their VO2max. Plasma concentrations of vascular endothelial growth factor (VEGF-A165), VEGF receptor 1 (sVEGFr-1), VEGF receptor 2 (sVEGFr-2), metalloproteinase 2 (MMP-2), and endostatin were measured at rest, after exercise, and at 1.5 and 3.0 hours during recovery.

RESULTS

The two-way analysis of variance showed non-significant main effects of "group" and significant main effects of "time/exercise" for all angiogenic biomolecules examined (P < 0.01-0.001). The arm-cranking exercise significantly increased plasma concentrations of VEGF, sVEGFr-1, sVEGFr-2, MMP-2, and endostatin in both groups (P < 0.001-0.01). The magnitude of the increase was similar in both patients with SCI and AB individuals, as shown by the non-significant group × time interaction for all angiogenic parameters.

CONCLUSIONS

Upper-limb exercise (arm-cranking for 30 minutes at 60% of VO2max) is a sufficient stimulus to trigger a coordinated circulating angiogenic response in patients with SCI. The response of angiogenic molecules to upper-limb aerobic exercise in SCI appears relatively similar to that observed in AB individuals.

Hypoxia-inducible factor-1 alpha in the heart: a double agent?

Hypoxia-inducible factor (HIF) is a set of transcription factors that regulate the cellular response to hypoxia. There is a great body of evidence supporting the protective role of HIF-1α in cardiovascular pathophysiology, however, newer studies are hinting at a maladaptive and deleterious role of this transcription factor that merits further investigation. There is a general agreement, however, that HIF-mediated responses appear to differ under conditions of acute and chronic oxygen deprivation. The intensity and sustainability of HIF-1α activation are major determinants of whether the responses are pathological or beneficial. HIF activation is seen to be beneficial in the setting of acute myocardial ischemia and deleterious in chronic conditions. In this review, we will focus on recent insights into the role of HIF-1α in the heart and especially in the setting of ischemic heart disease.

Disruption of components of vascular endothelial growth factor angiogenic signalling system in metabolic syndrome. Findings from a study conducted in rural Bangladeshi women

Metabolic syndrome (MetS) is associated with impaired angiogenesis, a process that is chiefly regulated by vascular endothelial growth factor (VEGF) upon binding to its specific receptors, VEGF-R1 and VEGF-R2. The purpose of the present study was to assess trends or patterns in plasma levels of VEGF and its soluble receptors in subjects with (MetS) or without (non-MetS) MetS; and further examine their association with clinical or metabolic parameters using a subpopulation of South Asian country. A total of 1,802 rural Bangladeshi women aged ≥15 years were studied using a population-based cross-sectional survey. Plasma levels of VEGF were found to be significantly increased (MetS vs. non-MetS: 483.9 vs. 386.9, p<0.001), whereas, the soluble forms of VEGF receptors, sVEGF-R1 and sVEGF-R2, were significantly decreased in subjects with Mets (sVEGF-R1, MetS vs. non-MetS: 512.5 vs. 631.3, p<0.001; sVEGF-R2, MetS vs. non-MetS: 9,302.8 vs. 9,787.4, p=0.004). After adjustment for age and all potential variables, multiple regression analysis revealed that plasma levels of VEGF had significant positive association with blood glucose (p = 0.019) and body mass index (p = 0.007). We also found that mean plasma levels of VEGF increased in direct proportion to levels of MetS components. The present study is the first ever to demonstrate a positive association between trends in levels of plasma VEGF and MetS using a large sample size from South Asia. The association between plasma VEGF and MetS needs further investigations in order to clearly decipher the clinical predictive value and accuracy of plasma VEGF in MetS.

Angiogenic factors in women ten years after severe very early onset preeclampsia

Background

Women with a history of mainly severe and early onset preeclampsia have an increased risk of future cardiovascular disease. During these complicated pregnancies increased levels of anti-angiogenic factors can be found. We hypothesize that women with a history of severe very early onset preeclampsia still have increased levels of these biomarkers years after this pregnancy, resulting in increased risk for cardiovascular disease.

Methods

Twenty women with severe early onset preeclampsia before 24 weeks' gestation, who delivered between 1993–2003 in a tertiary referral centre and twenty matched controls with uncomplicated pregnancies and healthy term infants, were addressed for participation in the study. Venous plasma samples were analyzed for basic fibroblast growth factor (bFGF), placental growth factor (PLGF), soluble fms-like tyrosine kinase-1 (sFlt-1), vascular endothelial growth factor (VEGF), E- and P-selectin, soluble intercellular adhesion molecule-3 (sICAM-3) and thrombomodulin by ELISA.

Results

Sixteen case subjects and 18 control subjects consented participation. The median time interval index pregnancy to study was 9.4 and 9.7 years for cases and controls, respectively. Median levels for cases-controls (p-value) were not different; bFGF: 17.43–11.11 pg/mL (0.33), sFlt-1: 102.98–101.92 pg/ml (0.84), PLGF: 3.57–4.20 pg/mL (0.38), VEGF: 64.05–45.72 pg/mL (0.73), E-selectin: 5.11–4.68 ng/mL (0.20), P-selectin: 85.35–71.69 ng/mL (0.69), sICAM-3: 0.42–0.63 ng/mL (0.41) and Thrombomodulin: 0.92–0.93 ng/mL (0.59).

Conclusion

There were no differences in angiogenic biomarkers between women with a history of severe early onset preeclampsia versus uncomplicated pregnancy almost 10 years later, suggesting that these angiogenic factors will not contribute to the early detection of women at risk for future cardiovascular disease.