Circulating adhesion molecules and arterial stiffness

Identification of common and specific fibrosis-related genes in three common chronic kidney diseases

BACKGROUND

Kidney fibrosis is the common final pathway of virtually all advanced forms of chronic kidney disease (CKD) including diabetic nephropathy (DN), IgA nephropathy (IgAN) and membranous nephropathy (MN), with complex mechanism. Comparative gene expression analysis among these types of CKD may shed light on its pathogenesis. Therefore, we conducted this study aiming at exploring the common and specific fibrosis-related genes involved in different types of CKD.

METHODS

Kidney biopsy specimens from patients with different types of CKD and normal control subjects were analyzed using the NanoString nCounter® Human Fibrosis V2 Panel. Genes differentially expressed in all fibrotic DN, IgAN and MN tissues compared to the normal controls were regarded as the common fibrosis-related genes in CKD, whereas genes exclusively differentially expressed in fibrotic DN, IgAN or MN samples were considered to be the specific genes related to fibrosis in DN, IgAN and MN respectively. Quantitative real-time PCR (qRT-PCR) was performed to validate the expression of the selected genes.

RESULTS

Protein tyrosine phosphatase receptor type C (PTPRC), intercellular cell adhesion molecule-1 (ICAM1), vascular cell adhesion molecule-1 (VCAM1), interleukin 10 receptor alpha (IL10RA) and CC chemokine receptor 2 (CCR2) were identified as the potential common genes for kidney fibrosis in different types of CKD, while peroxisome proliferator-activated receptor alpha (PPARA), lactate oxidase (LOX), secreted phosphoprotein 1 (SPP1) were identified as the specific fibrosis-associated genes for DN, IgAN and MN respectively. qRT-PCR demonstrated that the expression levels of these selected genes were consistent with the NanoString analysis.

CONCLUSIONS

There were both commonalities and differences in the mechanisms of fibrosis in different types of CKD, the commonalities might be used as the common therapeutic targets for kidney fibrosis in CKD, while the differences might be used as the diagnostic markers for DN, IgAN and MN respectively. Inflammation was highly relevant to the pathogenesis of fibrosis. This study provides further insight into the pathophysiology and treatment of fibrotic kidney disease.

Associations between Cerebrovascular Function and the Expression of Genes Related to Endothelial Function in Hormonal Migraine

There is evidence to suggest that hormonal migraine is associated with altered cerebrovascular function. We aimed to investigate whether the expression of genes related to endothelial function in venous blood (1) might influence cerebrovascular function, (2) differs between hormonal migraineur and non-migraineur women, and (3) changes following resveratrol supplementation. This study utilised data obtained from 87 women (59 hormonal migraineurs and 28 controls) where RNA from venous blood was used to quantify gene expression and transcranial Doppler ultrasound was used to evaluate cerebrovascular function. Spearman's correlation analyses were performed between gene expression, cerebrovascular function, and migraine-related disability. We compared the expression of genes associated with endothelial function between migraineurs and non-migraineurs, and between resveratrol and placebo. The expression of several genes related to endothelial function was associated with alterations in cerebrovascular function. Notably, the expression of CALCA was associated with increased neurovascular coupling capacity (p = 0.013), and both CALCA (p = 0.035) and VEGF (p = 0.014) expression were associated with increased cerebral blood flow velocity in the overall study population. Additionally, VCAM1 expression correlated with decreased pulsatility index (a measure of cerebral arterial stiffness) (p = 0.009) and headache impact test-6 scores (p = 0.007) in the migraineurs. No significant differences in gene expression were observed between migraineurs and controls, or between placebo and resveratrol treatments in migraineurs. Thus, altering the expression of genes related to endothelial function may improve cerebrovascular function and decrease migraine-related disability.

Biomarkers of cardiometabolic complications in survivors of childhood acute lymphoblastic leukemia

Survivors of childhood acute lymphoblastic leukemia (cALL) are at higher risk of developing cardiometabolic complications. We aimed at exploring the associations between biomarkers of inflammation, oxidative stress, endothelial function, endotoxemia and cardiometabolic risk factors. We conducted a cross-sectional analysis in 246 cALL survivors (mean age, 22.1 ± 6.3 years; mean time since diagnosis, 15.5 ± 5.2 years) and evaluated the associations using a series of logistic regressions. Using structural equation models, we also tested if the relationship between endotoxemia and cardiometabolic complications was mediated by the latent (unobserved) variable inflammation inferred from the observed biomarkers CRP, TNF-α and IL-6. High leptin-adiponectin ratio was associated with obesity [adjusted OR = 15.7; 95% CI (6.2–39.7)], insulin resistance [20.6 (5.2–82.1)] and the metabolic syndrome [11.2 (2.6–48.7)]. Higher levels of plasminogen activator inhibitor-1 and tumor necrosis factor-α were associated with obesity [3.37 (1.6–7.1) and 2.34 (1.3–4.2), respectively] whereas high C-reactive protein levels were associated with insulin resistance [3.3 (1.6–6.8)], dyslipidemia [2.6 (1.4–4.9)] and MetS [6.5 (2.4–17.9)]. Our analyses provided evidence for a directional relationship between lipopolysaccharide binding protein, related to metabolic endotoxemia, inflammation and cardiometabolic outcomes. Identification of biomarkers and biological mechanisms could open new avenues for prevention strategies to minimize the long-term sequelae, improve follow-up and optimize the quality of life of this high-risk population.

Saponins from Tribulus terrestris L. Extract Down-regulate the Expression of ICAM-1, VCAM-1 and E-selectin in Human Endothelial Cell Lines

Atherosclerosis is an inflammatory disease in which intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin (SELE) are consistently expressed in the vascular endothelium. Several evidence support the crucial role of adhesion molecules in the development of atherosclerosis and plaque instability. Due to the anti-inflammatory activity of Tribulus terrestris (TT), the present study investigated the effect of aqueous extract and saponin fraction of TT on the expression of ICAM-1, VCAM-1, and SELE genes in endothelial cells during normal and lipopolysaccharide (LPS) induced conditions. Human umbilical vein endothelial cells (HUVEC) and human bone marrow endothelial cells (HBMEC) were cultured, stimulated by LPS, and treated with aqueous extract and saponin fraction of TT. Finally, the expression of ICAM-1, VCAM-1, and SELE genes were measured using quantitative real-time polymerase chain reaction. LPS-induced HUVECs and HBMECs significantly increased the expression of ICAM-1, VCAM-1, and SELE in comparison with control groups (P<0.001). Treatment of LPS-induced HUVECs and HBMECs by aqueous extract and saponin fraction of TT decreased the expression of all three mentioned genes significantly (P<0.001) in comparison with LPS-induced cells. Taken together, our data suggest that TT has an anti-inflammatory effect. In vivo study about anti-inflammatory effect of this herb may provide new insights into the development of a herbal drug for the prevention/therapy of atherosclerosis.

Circulating levels of P-selectin and E-selectin relate to cardiovascular magnetic resonance-derived aortic characteristics in young adults from the general population, a cross-sectional study

BACKGROUND

Although endothelial cell adhesion molecules (CAMs) are postulated to play a key role in early atherosclerosis, studies on endothelial CAMs are mainly pertained to middle-aged populations and populations with an unfavourable cardiovascular risk burden. Therefore, this study evaluated whether circulating endothelial CAMs are related to cardiovascular magnetic resonance imaging (CMR) derived indicators of arterial wall alterations in a random sample of young adults from the general population.

METHODS

This cross-sectional study is part of the general-population-based Atherosclerosis-Monitoring-and-Biomarker-measurements-In-The-YOuNg (AMBITYON) cohort study. In 131 adults (age: 25-35 years), demography, anthropometry and a lipid spectrum was acquired. Thoracic aortic wall area, wall thickness and pulse wave velocity (PWV) were measured using a 3 T CMR-system. From stored blood samples, four CAMs (E-selectin, P-selectin, vascular CAM-1 and intercellular CAM-1) were measured using dedicated methods. Linear mixed-effects regression analysis was used to evaluate the relation of these CAMs with the selected aortic characteristics.

RESULTS

Of the studied endothelial CAMs, P-selectin related to natural logarithm transformed aortic wall thickness (β = 0.18 mm/(μg/ml), [95% confidence interval: 0.04, 0.31], p = 0.01) whereas E-selectin related to natural logarithm transformed aortic PWV (β = 3.01 (m/s)/(μg/ml), [95% confidence interval: 0.08, 5.95], p = 0.04). Of note, VCAM-1 and ICAM-1 did not relate to the selected aortic characteristics.

CONCLUSIONS

In young adults from the general population, circulating P-selectin and E-selectin levels appear positively related to CMR-derived aortic wall thickness and PWV, possibly pointing towards atherogenic inflammatory arterial wall alterations inflicted by these CAMs already in young adulthood.

TRIAL REGISTRATION

Netherlands National Trial Register (NTR): NTR4742 , Registered 18 August 2014, retrospectively registered.

Inflammatory Markers for Arterial Stiffness in Cardiovascular Diseases

Arterial stiffness predicts an increased risk of cardiovascular events. Inflammation plays a major role in large arteries stiffening, related to atherosclerosis, arteriosclerosis, endothelial dysfunction, smooth muscle cell migration, vascular calcification, increased activity of metalloproteinases, extracellular matrix degradation, oxidative stress, elastolysis, and degradation of collagen. The present paper reviews main mechanisms explaining the crosstalk between inflammation and arterial stiffness and the most common inflammatory markers associated with increased arterial stiffness, considering the most recent clinical and experimental studies. Diverse studies revealed significant correlations between the severity of arterial stiffness and inflammatory markers, such as white blood cell count, neutrophil/lymphocyte ratio, adhesion molecules, fibrinogen, C-reactive protein, cytokines, microRNAs, and cyclooxygenase-2, in patients with a broad variety of diseases, such as metabolic syndrome, diabetes, coronary heart disease, peripheral arterial disease, malignant and rheumatic disorders, polycystic kidney disease, renal transplant, familial Mediterranean fever, and oral infections, and in women with preeclampsia or after menopause. There is strong evidence that inflammation plays an important and, at least, partly reversible role in the development of arterial stiffness, and inflammatory markers may be useful additional tools in the assessment of the cardiovascular risk in clinical practice. Combined assessment of arterial stiffness and inflammatory markers may improve non-invasive assessment of cardiovascular risk, enabling selection of high-risk patients for prophylactic treatment or more regular medical examination. Development of future destiffening therapies may target pro-inflammatory mechanisms.