Circulating levels of interleukin-8 and vascular endothelial growth factor in patients with carotid stenosis

Platelet-Derived Growth Factor Is Associated with Progression of Symptomatic Intracranial Atherosclerotic Stenosis

BACKGROUND AND PURPOSE

We aimed to determine the relationships of 33 biomarkers of inflammation, oxidation, and adipokines with the risk of progression of symptomatic intracranial atherosclerotic stenosis (ICAS).

METHODS

Fifty-two of 409 patients who participated in the TOSS-2 (Trial of Cilostazol in Symptomatic Intracranial Stenosis-2) showed progression of symptomatic ICAS in magnetic resonance angiography at 7 months after an index stroke. We randomly selected 20 patients with progression as well as 40 age- and sex-matched control patients. We serially collected blood samples at baseline, 1 month, and 7 months after an index stroke. Multiplex analysis of biomarkers was then performed.

RESULTS

Demographic features and risk factors such as hypertension, diabetes, and smoking history were comparable between the two groups. Univariate analyses revealed that the levels of platelet-derived growth factor (PDGF)-AA [median (interquartile range)=1.64 (0.76-4.57) vs. 0.77 (0.51-1.71) ng/mL], PDGF-AB/BB [10.31 (2.60-25.90) vs. 2.35 (0.74-6.70) ng/mL], and myeloperoxidase [10.5 (7.5-22.3) vs. 7.8 (5.5-12.2) ng/mL] at 7 months were higher in the progression group. In the multivariate analysis using logistic regression, the PDGF AB/BB level at 7 months was independently associated with the progression of ICAS (p=0.02).

CONCLUSIONS

The PDGF-AB/BB level is associated with the progression of ICAS, and so may play a significant role in the progression of human ICAS.

Correlation of Plasma Vascular Endothelial Growth Factor and Endostatin Levels with Symptomatic Intra- and Extracranial Atherosclerotic Stenosis in a Chinese Han Population

BACKGROUND

Symptomatic intracranial atherosclerotic stenosis (ICAS) and extracranial atherosclerotic stenosis (ECAS) are different in many aspects. Here, we explored the association between the location or severity of atherosclerotic stenosis and pro- or antiangiogenic factors, specifically vascular endothelial growth factor (VEGF) and endostatin (ES).

METHODS

We evaluated 198 consecutive patients with acute ischemia stroke: 132 with large-artery atherosclerosis (LAA) and 66 with small-artery occlusion (small-vessel occlusion). The LAA group was subclassified into 102 patients with ICAS and 30 with ECAS. Independent associations of VEGF, ES levels, and VEGF/ES ratio with the location of cerebral stenosis and the severity or short-term prognosis (14th day modified Rankin Scale) of ICAS were evaluated.

RESULTS

Plasma concentrations of VEGF and ES were lower (P < .05) in ICAS (38.07, 32.76-46.28 pg/mL and 58.95, 55.04-59.77 ng/mL) than those in ECAS (45.00, 34.30-83.34 pg/mL and 140.74, 85.63-231.21 ng/mL). Logistic regression analysis showed that VEGF concentrations and dyslipidemia were independently associated with ICAS, with odds ratios of .987 [95% CI = (.976, .998)] and .265 [95% CI = (.103, .792)], respectively. Moreover, plasmatic VEGF levels increased gradually along with the severity of ICAS (P = .003), and lower levels of ES (P = .040) or a higher VEGF/ES ratio (P = .048) were related to unfavorable short-term prognosis of ICAS.

CONCLUSION

Lower VEGF levels are associated with the presence of symptomatic ICAS, but not with ECAS. Furthermore, the severity of ICAS is positively correlated with the levels of VEGF, and lower ES levels or a predominance of VEGF over ES are predictors of poor short-term prognosis of ICAS.

Local perivascular adiponectin associates with lower extremity vascular operative wound complications

BACKGROUND

Wound complication rates after lower extremity vascular operative procedures stand as high as 40% and represent a major cause of morbidity, mortality, and cost. In view of increasing recognition of adipose tissue involvement in homeostasis and the response to injury, we hypothesized that adipose phenotype is linked to operative wound outcomes.

METHODS

Clinical history, peripheral blood, and subcutaneous and perivascular adipose tissue were prospectively collected at the time of operation in patients undergoing lower extremity revascularization and lower extremity amputations. Nine biologic mediators (adiponectin; interleukin [IL]-1β, IL-6, and IL-8; leptin; monocyte chemoattractant protein-1; plasminogen activator inhibitor-1; resistin; and tumor necrosis factor) were assayed in the adipose tissues and plasma. The 30-day wound complications were captured in real time. Logarithmic transformation of mediator levels was performed based on positively skewed, non-Gaussian distribution, and data were compared using the Student t test. Bonferroni correction was used for multiple comparisons.

RESULTS

Sixty-six patients undergoing lower extremity revascularization or lower extremity amputations for severe peripheral arterial disease were enrolled. The 30-day follow-up was 92.4%. In total, 19 (29%) patients developed wound complications. Patients who developed wound complications had elevated perivascular adiponectin levels (mean ± standard error, 2,372.45 ± 648.64 ng/mL vs 832.53 ± 180.54 ng/mL, P = .004). Perivascular IL-1β levels were lower among patients with wound dehiscence (0.41 ± 0.004 pg/mL vs 0.73 ± 0.09 pg/mL, P = .001).

CONCLUSION

Local adipose tissue mediator levels at the time of operation demonstrate a previously undescribed compartment-specific relationship to wound outcomes in patients undergoing lower extremity vascular operative procedures. These associations provide fertile directives for defining the mechanisms underlying the pathogenesis of wound complications and their prevention.

Targeted delivery of human iPS-ECs overexpressing IL-8 receptors inhibits neointimal and inflammatory responses to vascular injury in the rat

Interleukin-8 (IL8) is highly expressed by injured arteries in a variety of diseases and is a chemoattractant for neutrophils which express IL8 receptors IL8RA and RB (IL8RA/B) on their membranes. Neutrophils interact with the damaged endothelium and initiate an inflammatory cascade at the site of injury. We have generated a novel translational targeted cell therapy for acute vascular injury using adenoviral vectors to overexpress IL8RA/B and green fluorescent protein (GFP) on the surface of endothelial cells (ECs) derived from human induced pluripotent stem cells (HiPS-IL8RA/B-ECs). We hypothesize that HiPS-IL8RA/B-ECs transfused intravenously into rats with balloon injury of the carotid artery will target to the injured site and compete with neutrophils, thus inhibiting inflammation and neointima formation. Young adult male Sprague-Dawley rats underwent balloon injury of the right carotid artery and received intravenous transfusion of saline vehicle, 1.5 × 10(6) HiPS-ECs, 1.5 × 10(6) HiPS-Null-ECs, or 1.5 × 10(6) HiPS-IL8RA/B-ECs immediately after endoluminal injury. Tissue distribution of HiPS-IL8RA/B-ECs was analyzed by a novel GFP DNA qPCR method. Cytokine and chemokine expression and leukocyte infiltration were measured in injured and uninjured arteries at 24 h postinjury by ELISA and immunohistochemistry, respectively. Neointimal, medial areas, and reendothelialization were measured 14 days postinjury. HiPS-IL8RA/B-ECs homed to injured arteries, inhibited inflammatory mediator expression and inflammatory cell infiltration, accelerated reendothelialization, and attenuated neointima formation after endoluminal injury while control HiPS-ECs and HiPS-Null-ECs did not. HiPS-IL8RA/B-ECs transfused into rats with endoluminal carotid artery injury target to the injured artery and provide a novel strategy to treat vascular injury.

Keloid scarring, but not Dupuytren's contracture, is associated with unexplained carotid atherosclerosis

BACKGROUND

Atherosclerosis, a response to injury, may be thought of as scarring in the artery wall. TGF-beta and associated signaling molecules have been implicated in the pathophysiology of keloid scarring, Dupuytren's Contracture and atherosclerotic plaques in independent studies.

PURPOSE

To test the hypothesis that excess cutaneous scarring and Dupuytren's contractures predispose independently to carotid atherosclerosis .

METHODS

Among 1,747 patients with plaque measurements and complete data for multivariable regression analysis, 57 Caucasian patients had Dupuytren's contractures and 12 had keloid scars. Carotid total plaque area (TPA) was measured by 2-Dimensional ultrasound.

RESULTS

In linear multivariable regression analysis with coronary risk factors, keloid scars were associated with TPA (P= 0.018), but Dupuytren's contractures were not. Patients with keloid scarring were younger (P < 0.0001), and more likely to be diabetic (P < 0.0001)

CONCLUSIONS

Keloid scarring is a clinical clue to excess atherosclerosis not explained by traditional risk factors. Such patients may benefit from therapy directed at targets related to signalling molecules common to both the process of keloid scarring and atherosclerosis. These findings suggest previously unexplored possibilities for the prevention and treatment of atherosclerosis. The differences between Dupuytren's and keloid scars that may identify such targets are discussed.

Intracellular expression of cytokines in peripheral blood from patients with atherosclerosis before and after carotid endarterectomy

OBJECTIVE

We investigated the possible association of intracellular cytokine profiles in peripheral mononuclear cells in whole blood from patients with carotid atherosclerosis in whom follow-up after carotid endarterectomy (CEA) showed the onset or progression of contralateral disease.

METHODS AND RESULTS

Intracellular expression of tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-1beta, IL-6, IL-8, IL-4 and IL-10 was determined in 43 patients with carotid atherosclerosis, at baseline and at 1, 3, 6 and 12 months after CEA, and in 16 healthy subjects. When follow-up ended patients were divided into two groups, those with cured or stable disease (no onset of disease or unchanged stenosis in the contralateral vessel) and those with progressive disease (onset of disease or increased stenosis in the contralateral vessel). In patients with cured or stable disease, cytokine-positive cells significantly decreased or remained unchanged (IL-8 and IL-10) during follow-up, whereas in patients with progressive disease they increased or remained unchanged (TNF-alpha). Multivariate ANOVA confirmed that the trend of cytokine expression between baseline and 12 months differed significantly in the two groups.

CONCLUSIONS

Intracellular expression of TNF-alpha, IFN-gamma, IL-1beta, IL-6, IL-8, IL-4 and IL-10 in peripheral mononuclear cells is associated with the outcome of contralateral disease after CEA.

Essential roles of angiotensin II in vascular endothelial growth factor expression in sleep apnea syndrome

BACKGROUND

Hypoxia-induced endothelial cell dysfunction has been implicated in increased cardiovascular disease associated with obstructive sleep apnea syndrome (OSAS). OSAS mediates hypertension by stimulating angiotensin II (Ang II) production. Hypoxia and Ang II are the major stimuli of vascular endothelial growth factor (VEGF), which is a potent angiogenic cytokine and also contributes to the atherogenic process itself.

METHODS AND RESULTS

We observed serum Ang II and VEGF levels and peripheral blood mononuclear cell (PBMC) and neutrophil VEGF expression. Compared to controls, subjects with OSAS had significantly increased levels of serum Ang II and VEGF and VEGF mRNA expression in their leukocytes. To examine whether Ang II stimulates VEGF expression in OSAS, we treated PBMCs obtained from control subjects with Ang II and with an Ang II receptor type 1 (AT(1)) blocker, olmesartan. We observed an increased expression of VEGF in the Ang II-stimulated PBMCs and decreased in VEGF mRNA and protein expression in the PBMCs treated with olmesartan.

CONCLUSIONS

These findings suggest that the Ang II-AT(1) receptors pathway potentially are involved in OSAS and VEGF-induced vascularity and that endothelial dysfunction might be linked to this change in Ang II activity within leukocytes of OSAS patients.

Pulse wave velocity as an indicator of atherosclerosis in obstructive sleep apnea syndrome patients

OBJECTIVE

Obstructive sleep apnea syndrome (OSAS) is associated with increased cardiovascular morbidity and mortality. We investigated the values of brachial-ankle pulse wave velocity as an indicator of atherosclerosis in obstructive sleep apnea syndrome patients.

MATERIALS AND METHODS

Brachial-ankle pulse wave velocity (baPWV) was measured in 104 OSAS patients and 104 healthy control subjects matched for age, sex, and body mass index (BMI). BaPWV values were compared in both groups and investigated with respect to the number of risk factors for atherosclerosis, including hypertension, hypercholesterolemia, impaired glucose tolerance, smoking, and obesity. Comparisons were also made between 48 OSAS group cases and 90 control group cases free from hypertension, which has a major impact on baPWV.

RESULTS

As compared to the control group, the OSAS group had significantly higher baPWV (1,645+/-349 cm/s vs 1,436+/-278 cm/s, p<0.0001), and values obtained for baPWV were significantly higher in the OSAS group than in the control group even in groups free from hypertension (1,453+/-216 cm/s vs 1,374+/-213 cm/s, p<0.05). In both groups, baPWV rose as the number of risk factors for atherosclerosis increased, but baPWV was higher in the OSAS group than in the control group even in a comparison of individuals entirely free from risk factors (1,400+/-200 cm/s vs 1,198+/-79 cm/s, p<0.05).

CONCLUSION

The condition of OSAS itself is considered a possible risk factor for atherosclerosis. We believe that the usefulness of baPWV as an index of atherosclerosis merits further study in the frequently observed cases of OSAS complicated by cardiovascular disease.

Evidence for a Proinflammatory and Proteolytic Environment in Plaques From Endarterectomy Segments of Human Carotid Arteries

Objectives Based on previous observations on apolipoprotein(a), apo(a), in human unstable carotid plaques, we explored whether in the inflammatory environment of human atheroma, proteolytic events affect other hepatic and topically generated proteins in relation to the issue of plaque stability.

Methods and Results Forty unstable and 24 stable plaques from endarterectomy segments of affected human carotid arteries were extracted with buffered saline (PBS) and then 6 mol/L guanidine-hydrochloride (GdHCl) to identify loosely and tightly bound products, respectively. The extracts were studied before and after ultracentrifugation at d 1.21 g/mL. In the extracts, the concentrations of interleukin (IL)-6, −8, and −18 were significantly higher in the unstable plaques and correlated to those of MMP-2 and MMP-9. By Western blots, both apoB and apo(a) were highly fragmented and mostly present in the d 1.21 bottom that also contained fragments of apoE (10 and 22 kDa), decorin, biglycan, and versican. Fragmentation was higher in the unstable plaques. In baseline plasmas, concentrations of lipids, lipoproteins, and ILs did not differ between patients with unstable and stable plaques.

Conclusions In unstable and to a lesser extent in stable plaques, there is a proinflammatory and proteolytic microenvironment with the generation of fragments with potential pathobiological significance that requires investigation.

Plasma vascular endothelial growth factor in sleep apnea syndrome: effects of nasal continuous positive air pressure treatment

Sleep apnea syndrome is associated with recurrent episodic hypoxia during sleep, which has been implicated in the development of cardiovascular morbidity. Hypoxia is the major stimulus of vascular endothelial growth factor (VEGF), which is a potent angiogenic cytokine. In the present article we describe the results of three experiments in which plasma concentrations of VEGF were measured in patients with sleep apnea. In Experiment 1, apnea-hypopnea index was found to be a significant independent predictor of morning VEGF concentrations in 85 male subjects investigated in the sleep laboratory, of whom 47 had an apnea-hypopnea index greater than 20. In Experiment 2, VEGF concentrations measured hourly during the sleep period were found to be significantly higher in a group of five sleep apnea patients compared with six age-similar snorers and six normal young adults (129.1 +/- 43.4 versus 74.6 +/- 11.5 and 32.5 +/- 12.8 pg/ml, respectively [p < 0.007]). In Experiment 3, VEGF concentrations were compared in patients with sleep apnea before and 1 year after nasal continuous positive airway pressure treatment. A significant decrease in VEGF concentrations was found only in patients in whom nocturnal hypoxia improved after treatment (57.1 +/- 62.5 versus 39.6 +/- 46.9 pg/ml, p < 0.01). There was no comparable improvement in patients who did not accept treatment (53.9 +/- 23.6 versus 54.0 +/- 21.5 pg/ml, ns). These results raise the possibility that VEGF may contribute to the long-term adaptation of sleep apnea syndrome to recurrent nocturnal hypoxia.