Prognostic value of serum von Willebrand factor, but not soluble ICAM and VCAM, for mortality and cardiovascular events is independent of residual renal function in peritoneal dialysis patients

Inflammation and all-cause mortality in patients undergoing peritoneal dialysis

OBJECTIVE

This study aimed to evaluate inflammatory biomarkers in patients undergoing peritoneal dialysis and investigate their association with all-cause mortality or transfer to hemodialysis.

METHODS

This prospective cohort study included 43 patients undergoing peritoneal dialysis. Plasma levels of cytokines were measured using flow cytometry and capture enzyme-linked immunosorbent assay. Biomarkers were categorized based on their respective median values. Survival analysis was conducted using the Kaplan-Meier estimator, considering two outcomes: all-cause mortality and transfer to hemodialysis.

RESULTS

After adjusting for confounding factors, plasma levels above the median of the levels of CCL2 and plasma, as well as below the median of TNF-α, and the median of dialysate IL-17 levels, were associated with an increased risk of experiencing the specified outcomes after approximately 16 months of follow-up.

CONCLUSION

These findings suggest that inflammatory biomarkers may be a valuable tool for predicting all-cause mortality and transfer to hemodialysis in patients undergoing peritoneal dialysis.

Secretory activity of the coronary artery endothelial cells in conditions of the peritoneal dialysis

Introduction

Endothelial dysfunction is frequent in patients treated with peritoneal dialysis and may lead to cardiac complications. We evaluated the effect of effluent dialysates and serum on the function of coronary artery endothelial cells (CAEC).

Methods

Human CAEC in in vitro culture were exposed to serum and dialysates from 24 patients treated with continuous ambulatory peritoneal dialysis (CAPD) and secretion of interleukin-6 (IL6), von Willebrand factor (vWF), tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) were measured. Modulation of the secretory activity of CAEC by Sulodexide, mixture of glycosaminoglycans: heparin sulfate and dermatan sulfate, was studied.

Results

Serum from CAPD patients stimulated synthesis of IL6 (+93%), vWF (+18%), and PAI-1 (+20%) and did not change t-PA secretion in CAEC. Dialysates stimulated secretion of IL6 (+89%), vWF (+29%), and PAI-1 (+31%) and did not change t-PA synthesis. Dialysates collected in 12 patients after 6 months more strongly stimulated synthesis of IL6 (+37%) and PAI-1 (+7%). Sulodexide suppressed the secretory activity of CAEC stimulated by the studied sera: IL6 (–38%), vWF (–19%), t-PA (–13%), and PAI-1 (–12%).

Conclusions

Serum and the dialysate from CAPD patients induce inflammatory and prothrombotic reaction in coronary arterial endothelial cells. The general pattern of the observed effects for serum and dialysates was similar but the intensity of the effects was not identical. Sulodexide reduced these effects.

Relationship between the serum levels of Vitamin D and inflammatory markers in ESRD patients

BACKGROUND AND AIM

In patients with End-stage renal disease (ESRD), 25-(OH)-Vitamin D3 deficiency is a common problem and also the inflammatory responses increase in these patients. The present study aims to evaluate the relation of 25-(OH)-Vitamin D3 with the indirect inflammatory markers in patients on hemodialysis (HD) and peritoneal dialysis (PD).

METHODS

This study was done by cross-sectional method on 85 ESRD patients receiving renal replacement therapy (RRT), from one geographical area. 64 patients on HD and 21 patients on PD who were matched for age and sex were studied. Serum level of 25-(OH) Vitamin D3 was measured in each patient. ESR, CRP and the other routine blood tests were measured as well.

RESULTS

The level of 25-OH Vitamin D3 was significantly lower in PD group in comparison to HD group (P: 0/0012, 2/70±0/10 vs 2/05±0/14). Platelet (195/40 ± 7/6 vs 265/52 ± 15/6, P: 0/001) and ESR (46/80 ± 6/89 vs 23/53 ± 1/96, P: 0/003) were significantly higher in PD group. Considering total population of the study (PD and HD), there was a significant association between ESR and serum level of 25-(OH)-Vitamin D3 (r: 0.26, P: 0.036) but no correlation was seen between 25-(OH)-Vitamin D3 and hemoglobin (Hb) or duration of dialysis. On the other hand, in patients on HD, multiple regression analysis revealed a significant relationship between duration of dialysis (P: 0.02), Hb (P: 0.01) and ESR (P: 0.001) with 25-(OH)-Vitamin D3 level. Moreover, there was a relationship between vitamin D3 levels and inflammatory markers as well.

CONCLUSIONS

The deficiency of 25-(OH)-Vitamin D3 was followed with increase of ESR as an inflammatory marker in patients on HD. Key words: Inflammation; 25-hydroxy vitamin D; Renal replacement; Dialysis.

Overlapping pathogenic signalling pathways and biomarkers in preeclampsia and cardiovascular disease

OBJECTIVES

Preeclampsia is a cardiovascular pregnancy complication that occurs in 5-10% of pregnancies and it can lead to a number of pregnancy complications including maternal and foetal death. Long-term, preeclampsia is associated with up to 8-fold increased risk of cardiovascular disease (CVD) for both mothers and their offspring. The lack of mechanistic data in relation to the causes or consequences of preeclampsia has prevented the development of effective therapeutic and monitoring strategies.

STUDY DESIGN

This study investigates common underlying mechanisms of preeclampsia and CVD, specifically hypertension and heart failure with preserved ejection fraction (HFpEF), using "in silico" approach of publicly available datasets. Integrated techniques were designed to mine data repositories and identify relevant biomarkers associated with these three conditions.

MAIN OUTCOMES MEASURES

The knowledge base tools were employed that enabled the analysis of these biomarkers to discover potential molecular and biological links between these three conditions.

RESULTS

Our bioinformatics "in silico" analyses of the publically available datasets identified 76 common biomarkers between preeclampsia, hypertension and HFpEF. These biomarkers were representative of 29 pathways commonly enriched across the three conditions which were largely related to inflammation, metabolism, angiogenesis, remodelling, haemostasis, apoptosis and the renin-angiotensin-aldosterone (RAAS) system.

CONCLUSIONS

This bioinformatics approach uses the wealth of scientific data available in public repositories to gain a deeper understanding of the overlapping pathogenic mechanisms of associated diseases, which could be explored as biomarkers or targets to prevent long-term cardiovascular complications such as hypertension and HFpEF following preeclampsia.

Effect of Acute Myocardial Infarction on a Disintegrin and Metalloprotease with Thrombospondin Motif 13 and Von Willebrand Factor and Their Relationship with Markers of Inflammation

Objectives

Coagulation mechanisms and fibrinolytic assembly are important components role players of acute myocardial infarction (AMI) progression. Our study objective was to see the serial variations in the levels of Von Willebrand factor (VWF) and A Disintegrin and Metalloprotease with ThromboSpondin motif (ADAMTS13) over the course of AMI and to determine their relationship with the cardiovascular risk markers and the patient's clinical characteristics.

Methods

This project was done at the departments of Emergency Medicine, Physiology and Cardiac sciences of King Saud University Medical City. We studied ADAMTS13, VWF, fibrinogen, and CRP levels in 80 patients with AMI when patients were admitted; post AMI by 3-4 days and at follow-up of 3 months. We compared them with a control group consisting of 36 subjects.

Results

AMI had significantly lower levels of ADAMTS13 at AMI and after 3-4 days; at follow-up the difference in levels was nonsignificant, when compared with controls. Similarly, VWF levels were significantly higher in AMI and remained high even at follow-up compared to control subjects. VWF/ADAMTS13 ratio was also significantly higher at AMI and 3-4 days while at follow-up difference was nonsignificant compared to control subjects. Regression analysis between hsCRP and ADAMTS13 showed an inverse relationship (r = 0.376, p < 0.01), while correlation with VWF was significantly positive (r = 0.376, p < 0.01), while correlation with VWF was significantly positive (.

Conclusions

Increased levels of VWF and reduced levels of ADAMTS13 activity may contribute to the pathogenesis of acute myocardial infarction and might prove to be important mediators of AMI progression.

Endothelial dysfunction and low-grade inflammation in the transition to renal replacement therapy

Introduction

End-stage renal disease (ESRD) strongly associates with cardiovascular disease (CVD) risk. This risk is not completely mitigated by renal replacement therapy. Endothelial dysfunction (ED) and low-grade inflammation (LGI) may contribute to the increased CVD risk. However, data on serum biomarkers of ED and LGI during the transition to renal replacement therapy (dialysis and kidney transplantation) are scarce.

Methods

We compared serum biomarkers of ED and LGI between 36 controls, 43 participants with chronic kidney disease (CKD) stage 5 non-dialysis (CKD5-ND), 20 participants with CKD stage 5 hemodialysis (CKD5-HD) and 14 participants with CKD stage 5 peritoneal dialysis (CKD5-PD). Further, in 34 and 15 participants repeated measurements were available during the first six months following dialysis initiation and kidney transplantation, respectively. Serum biomarkers of ED (sVCAM-1, E-selectin, P-selectin, thrombomodulin, sICAM-1, sICAM-3) and LGI (hs-CRP, SAA, IL-6, IL-8, TNF-α) were measured with a single- or multiplex array detection system based on electro-chemiluminescence technology.

Results

In linear regression analyses adjusted for potential confounders, participants with ESRD had higher levels of most serum biomarkers of ED and LGI than controls. In addition, in CKD5-HD levels of serum biomarkers of ED and LGI were largely similar to those in CKD5-ND. In contrast, in CKD5-PD levels of biomarkers of ED were higher than in CKD5-ND and CKD5-HD. Similarly, in linear mixed model analyses sVCAM-1, thrombomodulin, sICAM-1 and sICAM-3 increased after PD initiation. In contrast, incident HD patients showed an increase in sVCAM-1, P-selectin and TNF-α, but a decline of hs-CRP, SAA and IL-6. Further, following kidney transplantation sVCAM-1, thrombomodulin, sICAM-3 and TNF-α were lower at three months post-transplantation and remained stable in the three months thereafter.

Conclusions

Levels of serum biomarkers of ED and LGI were higher in ESRD as compared with controls. In addition, PD initiation and, less convincingly, HD initiation may increase levels of selected serum biomarkers of ED and LGI on top of uremia per se. In contrast to dialysis, several serum biomarkers of ED and LGI markedly declined following kidney transplantation.

Cardiac risk assessment for end-stage renal disease patients on the renal transplant waiting list

Cardiovascular disease is a leading cause of morbidity and mortality and is becoming more prevalent as the population ages and risk factors increase. This is most apparent in the end-stage renal disease (ESRD) patient population. In part, this is due to cofactors such as diabetes and hypertension commonly predisposing to progressive renal disease, as well as being a direct consequence of having renal failure. Of all major organ failures, kidney failure is the most likely to be managed chronically using renal replacement therapy and, ultimately, transplant. However, lack of transplant organs and a large renal failure cohort means waiting lists are often quite long and may extend to 5-10 years. Due to the cardiac risk factors inherent in patients awaiting transplant, many succumb to cardiac issues while waiting and present an increased per-procedural cardiac risk that extends into the post-transplant period. We aim to review the epidemiology of coronary artery disease in this population and the etiology as it relates to ESRD and its associated co-factors. We also will review the current approaches, recommendations and evidence for management of these patients as it relates to transplant waiting lists before and after the surgery. Recommendations on how to best manage patients in this cohort revolve around the available evidence and are best customized to the institution and the structure of the program. It is not clear whether the revascularization of patients without symptoms and with a good functional status yields any improvement in outcomes. Therefore, each individual case should be considered based on the risk factors, symptoms and functional status, and approached as part of a multi-disciplinary assessment program.

Apolipoprotein E4 Expression Causes Gain of Toxic Function in Isogenic Human Induced Pluripotent Stem Cell-Derived Endothelial Cells

OBJECTIVE

The ApoE (apolipoprotein) allele epsilon 4 is a major genetic risk factor for Alzheimer disease, cardiovascular disorders, and stroke, indicating that it significantly impacts cerebral and vascular systems. However, very little is known about how APOE genotype affects brain endothelial cells, which form a network of tight junctions to regulate communication between the brain and circulating blood factors. Approach and Results: Here, we present a novel model of endothelial dysfunction using isogenic human induced pluripotent stem cell-derived cells harboring different alleles of the APOE gene, specifically ApoE 3/3, 3/4, and 4/4. We show for the first time that ApoE4 expression by endothelial cells is sufficient to cause a toxic gain of cellular dysfunction. Using RNAseq, we found significant effects of ApoE4 on signaling pathways involved in blood coagulation and barrier function. These changes were associated with altered cell function, including increased binding of platelets to ECs with the 3/4 or 4/4 genotype. ApoE4-positive cells exhibited a proinflammatory state and prothrombotic state, evidenced by higher secretion of Aβ (amyloid-β) 40 and 42, increased release of cytokines, and overexpression of the platelet-binding protein VWF (vonWillebrand factor). Immunohistochemistry of human brain Alzheimer disease brains also showed increased VWF expression with the ApoE4/4 genotype. Finally, pharmacological inhibition of inflammation in ECs by celastrol rescued overexpression of VWF in cells expressing ApoE4.

CONCLUSIONS

These cells provide novel insight into ApoE4-mediated endothelial dysfunction and provide a new platform to test potential therapies for vascular disorders.

Relation of smoking and endothelial dysfunction markers in systemic hypertension

Aim. Assessment of the markers levels of endothelial dysfunction (ED): stable metabolites of nitric oxide (NOx), endothelin-1 (E1), homocysteine (HC), von Willebrand factor (vWF) and tissue plasminogen activator (tPA) in blood plasma of smoker and nonsmoker patients with arterial hypertension (AH) of low and moderate risk, not taking antihypertension therapy regularly.

Material and methods. Totally, 124 AH patients included, 45 males and 79 females, mean age 51,4±6,5 y.o., mean AH duration 7,9±7,3 y. Controls included 35 healthy volunteers (20 males, 15 females). Concentration of NOx in plasma was measured with spectrophotometry, and of vWF, HC, E1 and tPA — with immune enzyme assay.

Results. To evaluate the relation of smoking and ED markers levels, AH patients and controls were selected to subgroups according to smoking status: smoker (35,5%) and non-smoker (64,5%) AH patients; smoker (38%) and non-smoker (62%) controls. In smoker AH patients comparing to non-smoking there were significantly higher concentrations of NOx — 48,2±18,8 mcM/L and 40,3±21,2 mcM/L, respectively (р<0,05), E1 — 1,2±0,16 and 0,6±0,2 fM/L, resp. (р<0,05), HC — 25,7±6,04 and 16,2±6,5 mcM/L, resp. (р<0,05), vWF — 1,39±0,7 and 1,1±0,6 mg/dL, resp (р<0,05) and tPA — 13,05±6,2 and 8,5±6,2 mcM/L, resp. (р<0,05). There was correlation in the AH group, of NOx concentration and smoking (r=0,46, р<0,05), and tobacco smoking duration (r=0,83, р<0,05). Also, there were positive correlations of HC and smoking (r=0,4, p<0,05). In control group smokers had higher HC — 20,7±5,3 and 17,2±4,7 mcM/L, resp. (р<0,05), vWF — 1,3±0,8 and 0,8±0,6 mg/dL, resp. (р<0,05) and tPA — 11,1±6,5 and 6,6±5,2 mcM/L, resp. (р<0,05). There were no significant changes in NOx and E1.

Conclusion. In smokers of both AH and control groups the levels of HC, vWF and tPA were significantly higher in comparison with nonsmokers. In smoker AH patients the mean concentrations of NOx and E1 are higher than in non-smoker patients. Levels of ED are related with not only the fact of smoking itself (р<0,05), but smoking duration (р<0,05).

Indoxyl sulfate - the uremic toxin linking hemostatic system disturbances with the prevalence of cardiovascular disease in patients with chronic kidney disease

Background

During chronic kidney disease progression, kidney-specific risk factors for cardiovascular disease come into play. The present study investigated the impact of indoxyl sulfate, dietary tryptophan-derived uremic toxin, accumulated in the blood of patients with chronic kidney disease on hemostatic parameters, markers of inflammation, oxidative stress and monocyte to macrophage transition.

Methods

Fifty-one CKD patients not undergoing hemodialysis were enrolled in the study. Coagulation factors, fibrinolytic parameters, adhesion molecules, endothelial dysfunction markers, oxidative stress as well as inflammation markers were examined using immune-enzymatic method. Indoxyl sulfate levels were assessed using high-performance liquid chromatography. Biochemical parameters were determined by routine laboratory techniques using an automated analyzers. All assessed parameters were compared with controls and subjected to cross-sectional statistical analysis.

Results

Elevated concentrations of indoxyl sulfate, the vast majority of parameters affecting hemostasis, and markers of renal insufficiency conditions were observed. Part of hemostatic factors, namely tissue factor, von Willebrand factor, thrombomodulin, soluble urokinase-type plasminogen activator receptor, soluble intercellular adhesion molecule-1, soluble vascular cell adhesion protein were correlated with the fraction of indoxyl sulfate. A significant quantity of assessed parameters showed strong correlations with superoxide-dismutase, renal insufficiency rate, C-reactive protein, and neopterin. Levels of indoxyl sulfate were independently associated with markers of impaired endothelial function (thrombomodulin, adhesion molecules), oxidative stress (superoxide-dismutase) and monocytes activation determinant (neopterin), which indicate unconventional links between these systems and the role of indoxyl sulfate. Furthermore, parameters that correlated with the levels of indoxyl sulfate (von Willebrand factor, soluble urokinase-type plasminogen activator receptor, soluble intercellular adhesion molecule-1) were positively associated with the prevalence of cardiovascular disease in a CKD patients.

Conclusions

The study demonstrated that in conditions of chronic exposure to uremic toxins, indoxyl sulfate seems to be one of the “missing links” between impaired renal function and prevalence of cardiovascular events, especially hemostatic disorders. The main functions of the action appear to be altered monocytes activation, intensified inflammatory process, and augmented oxidative stress by this uremic toxin.