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Arteriosclerosis, Thrombosis, and Vascular Biology. 1999;19:2659-2665

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(Arteriosclerosis, Thrombosis, and Vascular Biology. 1999;19:2659.)
© 1999 American Heart Association, Inc.


Vascular Biology

Increased Systemic Oxidative Stress After Elective Endarterectomy

Relation to Vascular Healing and Remodeling

Andrea Mezzetti; Maria D. Guglielmi; Sante D. Pierdomenico; Fabrizio Costantini; Francesco Cipollone; Domenico De Cesare; Tonino Bucciarelli; Sante Ucchino; Francesco Chiarelli; Franco Cuccurullo; Ferdinando Romano

From the Centro per lo Studio dell’Ipertensione Arteriosa delle Dislipidemie e dell’Aterosclerosi (A.M., M.D.G., S.D.P., F. Costantini, F. Cipollone, D.D.C., F. Chiarelli, F. Cuccurullo), the Department of Medicine and Aging Science, Institute of General Surgery (S.U.), and the Department of Biomedical Science (T.B., F.R.), University "Gabriele D’Annunzio," Chieti, Italy.

Correspondence to Prof Andrea Mezzetti, MD, Padiglione Biologico, IV livello-V Dente, Via Pescara, 66013-Chieti Scalo, Italy. E-mail mezzetti{at}unich.it


*    Abstract
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*Abstract
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Abstract—It has been reported that systemic and local redox state may have an important role in the functional and organic changes characterizing the process of vascular response to injury. Carotid endarterectomy to remove atherosclerotic plaque is followed by a long lasting healing and remodeling process that can be carefully followed over time with noninvasive ultrasonography. Plasma vitamin C concentration and native LDL (n-LDL) content in lipid peroxides, vitamin E, ß-carotene, and lycopene as well as LDL susceptibility to peroxidation were assessed in 45 patients undergoing elective endarterectomy for internal carotid stenosis, at baseline, 24 hours, 3 and 15 days, and 1 month after surgery. Serial duplex scans were performed in all patients postoperatively and 3, 6, and 12 months. The changes in far wall thickness (FW) and % renarrowing from postoperatively to 12 months were used as remodeling indices. Plasma antioxidant vitamins and lag-phase showed a sharp and significant decrease during the first 24-hours after surgery remaining unchanged until the third day, whereas, an opposite trend was evidenced for n-LDL content in lipid peroxides and serum ceruloplasmin. After the third day all the parameters returned progressively to baseline within one month from endarterectomy. Interestingly, the n-LDL lipid peroxide content, the serum ceruloplasmin and the plasma vitamin C concentration, measured at 24 and 3 days from surgery, were significantly associated to the change in % renarrowing from postoperatively to 12 months. The higher the LDL content in lipid peroxides, the higher the serum level of ceruloplasmin, the lower the plasma content in vitamin C and the higher the % of vessel renarrowing. In conclusion, carotid endarterectomy with atherosclerotic plaque removal is associated with an acute and prolonged increase in systemic oxidative stress that influences vascular healing and late luminal loss.


Key Words: endarterectomy • LDL oxidation • carotid artery • healing • vascular remodeling • ultrasonography


*    Introduction
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Carotid endarterectomy to remove atherosclerotic plaque restores blood flow and reduces the risk of cerebral ischemia.1 This current surgical procedure is followed by a long-lasting healing and remodeling process that in 4% to 22% of patients may induce the development of a recurrent carotid stenosis.1 2

Vascular repair and remodeling is a very complex phenomenon that involves a local intense inflammatory response, smooth muscle cell proliferation and migration, and extracellular matrix production and contraction. Thus it may be considered the vascular manifestation of a general biological response to tissue injury, reflecting the systemic wound-healing process.3 4 5 In this light it has recently been suggested that systemic and local redox states may have an important role in the functional and organic changes that characterize vessel healing and remodeling after invasive therapeutic procedures.6 7 8 In an animal model it has been shown that vascular repair is negatively influenced by a high oxidation state of circulating LDL and benefits from antioxidant vitamin administration.9 Recently, in humans, vascular surgery such as carotid endarterectomy and coronary angioplasty have been found to be associated with a transient increase in systemic oxidative stress.10 11 12 13 To investigate whether changes in systemic and LDL oxidative status may be associated with vascular healing and remodeling after an invasive therapeutic procedure, we chose the model of the internal carotid artery subjected to elective endarterectomy. This artery does not restenose very often to the extent that symptomatic recurrence needs further intervention,14 15 but the healing and remodeling process is easy to study over time with noninvasive ultrasonography.14 15 16


*    Methods
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*Methods
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Patient Selection
Forty-five patients (35 men, 10 women) admitted to the Vascular Surgery Division of The General Hospital of Chieti (Italy) for elective internal carotid endarterectomy were enrolled in the study.

Selection Criteria
Only patients admitted to the hospital with an indication for monolateral internal carotid endarterectomy were eligible for the study. Inclusion criteria were patients >=50 years of age (mean age±SD 63±9 years, range 50 to 75 years); >=70% internal carotid artery stenosis angiographically confirmed; history of transient ischemic attacks or amaurosis fugax; or a single nondebilitating stroke. All women were in the postmenopausal state, but none of them was receiving hormone replacement therapy. Exclusion criteria were current smoking; vitamin supplements or drugs with known antioxidant activity taken within 1 month before surgery; diabetes; previous carotid endarterectomy; impaired consciousness; serious disabling diseases; prosthetic patch angioplasty.

Characteristics of Patients Enrolled
Preoperative angiography demonstrated preocclusive lesions in 22 patients (>90%) and a 71% to 90% stenosis in the remaining 23 (Table 1Down). All patients were dyslipidemic (Fredrickson type IIa), and 68% were pharmacologically well-controlled hypertensives. Ischemic heart disease was diagnosed in 39% of the patients. None of the patients had significant peripheral vascular disease. All patients were receiving prophylactic treatment with aspirin (100 mg/d) and were following the step II American Heart Association diet throughout the study.


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Table 1. Clinical Characteristics and Serum Lipids and Lipoproteins at Baseline of the 42 Patients Who Completed the 12-Month Ultrasonographic Follow-Up

Follow-Up
The patients were followed up by serial duplex scanning performed after surgery and at 3, 6, and 12 months after hospital discharge. Only patients with high-quality B-mode ultrasonographic images of the proximal internal carotid artery were retained in the study. Fasting venous blood samples for determination of biochemical parameters were obtained from all the patients soon before surgery (baseline) and 24 hours, 3 days, 15 days, and 1 month after endarterectomy.

This study was approved by the Ethics Committee of the School of Medicine of the University "Gabriele D’Annunzio" of Chieti (Italy). All patients included in this study gave written informed consent.

Carotid Endarterectomy Procedure
A standard elective endarterectomy procedure was performed under general anesthesia by the same surgeon. Intraluminal shunts were used for patients with history of stroke, contralateral internal carotid artery stenosis, or occlusion with internal stump pressure <50 mm Hg.

Ultrasonographic Carotid Artery Measurements
Real time, B-mode ultrasound was used to evaluate the internal carotid artery. All examinations were performed by the same trained sonographer with a Hewlett Packard model 77030A ultrasound imaging system equipped with a 7.5-MHz transducer. Subjects were examined in the supine position, with a slight hyperextension of the neck. The internal carotid arteries were examined in a series of cross-sectional scans to select the angle of interrogation that would lead to a perpendicular longitudinal view at the site of the maximal wall thickness. The same interrogation angle was used for each patient during follow-up. Each scan was magnified and recorded on videotape. The indexes of renarrowing were measured from all of these video recordings by the same scanning physician at the end of the study period. The videotapes were read in random order, and the reader was blinded to the name of the patient and the number of the follow-up visit. In all the patients, the new intima-media thickness of the far wall (FW) and the percentage of renarrowing were measured after surgery and at 3, 6, and 12 months after hospital discharge. The FW thickness corresponds to the averaged value obtained on a 1-cm-long longitudinal section starting from the flow divider. The parietal thickness of the far wall was considered the distance from the leading edge of the first echogenic bright line (lumen–new intima interface) to the leading edge of the second echogenic line (wall-adventitia interface).17 All measurements were made at end-diastole by ECG triggering, with electronic calipers. Percentage of vascular renarrowing was calculated at the point of maximal lumen narrowing by dividing the difference of the reference lumen diameter (RLD) and the minimum lumen diameter (MLD) by the RLD, with the use of the morphometry software of the echo unit.17 The MLD was considered the distance between the leading edge of the new intima-lumen interface of the near wall and the leading edge of the lumen–new intima interface of the FW.18 The percent changes in FW thickness and in percent renarrowing (late luminal loss) from after surgery to 12 months of follow-up were used as final measures of the vascular healing and remodeling process. To assess intraobserver variability, 25% of the scans were randomly selected and reexamined by the scanning physician. The intraobserver coefficients of variation for FW thickness and percent renarrowing were 6.9% and 6.4%, respectively.

Laboratory Methods
Serum Lipids and Lipoprotein Assay
Total serum cholesterol and triglycerides were measured by standard enzymatic techniques (Chod-Pap MPR1, Boehringer Mannheim). HDL cholesterol was assessed by immunoturbidimetric technique. The LDL cholesterol (LDL-C) was calculated by Friedewald’s formula. Apoprotein AI and apoprotein B were determined by rate nephelometry.19

Plasma Vitamin C Determination
Plasma vitamin C was immediately assessed by a spectrophotometric method as previously described.19

LDL Isolation and Oxidation
Blood was drawn into test tubes containing EDTA (2.7 mmol/L). The LDL fraction was isolated by single vertical spin ultracentrifugation with a discontinuous NaCl/KBr density gradient as previously reported.20 21 22 LDL protein and cholesterol were determined by established methods.23 24

LDL (0.2 mg LDL-C/mL) oxidation was triggered by the addition of 5 µmol/L CuSO4 in phosphate-buffered saline, pH 7.4, 37°C. The lag phase preceding the formation of conjugated dienes was calculated as described previously.25

Lipid Peroxidation in Native LDL
To improve our measurement of native LDL (n-LDL) content in oxidation products, we used 2 different indirect indexes of lipid peroxidation.

Lipid peroxidation in n-LDL was assessed by measurement of fluorescent products of lipid peroxidation (FPLPs) and of thiobarbituric acid reactive substances (TBARS). FPLPs essentially reflect the interaction of aldehydic lipid peroxidation products with phospholipids and amino groups of the protein.21 25 26 27 The characteristic of these indicators is that they tend to be long-lived and to remain at the sites of oxidative damage.26 Briefly, an n-LDL sample (1 mL), diluted with PBS to a final protein concentration of 0.5 mg/mL, was mixed with 7 mL chloroform/methanol (2:1 vol/vol) plus water and briefly centrifuged. The lipid-containing phase was removed, dried under a stream of N2 gas at room temperature, resuspended in chloroform (2.5 mL), and exposed to ultraviolet light. Fluorescence values were estimated spectrofluorometrically at 360-nm excitation and 430-nm emission with the use of a Kontron SFM25 spectrofluorometer calibrated with quinine sulfate. Results were expressed as units of relative fluorescence (URF)/mg LDL-C.

The lipid peroxide content of n-LDL was also evaluated fluorometrically as TBARS.21 LDL (100 µg protein) was mixed with 1.5 mL of 0.67% thiobarbituric acid and 1.5 mL of 20% trichloroacetic acid containing 1 mg/mL EDTA. After heating at 100°C for 30 minutes, fluorescent reaction products were estimated spectrofluorometrically at 515-nm excitation and 553-nm emission with the use of a Kontron SFM25 spectrofluorometer. Freshly diluted tetramethoxypropane, which yields malondialdehyde (MDA), was used as a standard, and results were expressed as nanomoles of MDA equivalents per milligram of LDL-C (nmol MDA/mg LDL-C).

LDL Antioxidant Determination
LDL content in vitamin E, ß-carotene, and lycopene were determined by HPLC as previously reported.20 21 Vitamins were separated and quantified with the use of a Kontron system 450 equipped with a UV-visible, wavelength-variable Kontron Detector 430. Analysis was performed by isocratic elution. The flow rate was 1.5 mL/min. The mobile phase, consisting of methanol-butanol-water (89.5:5:5.5 vol/vol/vol), was premixed and vacuum-filtered through a 0.45-µm polypropylene membrane filter (Whatman) before use. Autoinjection of 10 µL of organic extract was performed with the use of a Waters autoinjector (model 717 plus Autosampler) refrigerated at 5°C. The analytical column used was a replaceable Partisphere 5 C18 cartridge (110 mmx4.7 mm ID, 5-µm particle size, Whatman) protected by a guard cartridge (C18, 5 µm) system and maintained at 45°C. Vitamin E, tocopherol acetate (internal standard), lycopene, and ß-carotene were detected by the UV-visible spectrophotometer at different wavelengths programmed for analysis as follows: at 0 minutes, 290 nm; 4.5 minutes, 280 nm; 15 to 22 minutes, 450 nm. Vitamins were expressed as micrograms per milligram of LDL-C (µg/mg LDL-C).

Ceruloplasmin Assay
Serum ceruloplasmin concentration was measured by immunonephelometry with a commercially available kit (QM300, Kallestad Diagnostics Inc) and expressed as milligrams per liter (mg/L). The coefficient of variation of ceruloplasmin content for analytic reproducibility was 2.9%.

Statistical Analysis
Data are reported as mean±SD. An ANOVA for repeated measures followed by a multiple comparison test (Scheffè’s test) was performed to test the changes in biochemical and ultrasonographic parameters measured over time. Simple and multiple linear regression analyses were also used.

First, the relation between the biochemical parameters of interest measured at different time points (24 hours, 3 days, 15 days, and 1 month) and the indexes of vascular renarrowing measured as the percent change from after surgery to 12 months was tested by use of simple linear regression analysis. Successively, multiple regression analyses were performed to test the association between changes in FW thickness and percent renarrowing from after surgery to 12 months, and changes over a 24-hour and a 3-day period in those biochemical parameters resulted, at the univariate analysis, as being significantly associated with the ultrasonographic indexes. Thus we created 4 different multiple regression models in which changes in FW thickness and percent renarrowing from after surgery to 12 months were, alternatively, the independent variables, and the changes of the biochemical parameters over the 24-hour period or over the 3-day period represented the dependent variables. All models have been adjusted for potential confounders (levels of the biochemical parameters before surgery, body mass index [BMI], age, sex, ischemic heart disease, systolic blood pressure, percent stenosis before surgery, duration of surgery). Statistical analysis was performed with the STATVIEWS 4.5 software (Abacus Concepts Inc) for the Macintosh Performa 5300 computer.


*    Results
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*Results
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Baseline clinical characteristics and levels of biochemical parameters of the patients enrolled in the study are reported in Table 1Up.

Ultrasonographic Measurements
The data are reported in Table 2Down. The ultrasonographic follow-up was carried out in 42 of the 45 patients enrolled in the study. Three male patients were excluded because of poor ultrasonographic images.


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Table 2. Changes in Ultrasonographic Indexes Throughout the Study

The FW thickness and the percent renarrowing of the internal carotid arteries increased significantly and progressively from after surgery to 12 months. FW increased from 0.88±0.23 to 1.58±0.41 mm (+79%, P<0.001) and percent renarrowing from 17±6.7% to 39±13.5% (+129%, P<0.001).

Time Course of Biochemical Parameters
Native LDL content in vitamin E, lycopene, ß-carotene, the lag phase, and plasma vitamin C concentration showed a sharp and significant decrease during the first 24 hours after surgery; these changes persisted unmodified after 3 days and returned progressively to baseline within 1 month of the surgical operation (Table 3Down). An opposite trend was seen for lipid peroxide n-LDL content (both indexes) and serum ceruloplasmin, which showed a rapid and significant increase in the first 24 hours, no change until the third day, and subsequent lowering to initial values after 1 month. The highest deviations from the baseline (measured at 24 hours) were n-LDL content in lipid peroxides (FPLPs, +53%, P<0.001; TBARS, +32%, P<0.001, respectively) and lycopene (-36%, P<0.001), plasma vitamin C (-27%, P<0.001), and serum ceruloplasmin (+24%, P<0.001). Lower but significant variations were recorded for lag-phase duration (-21%, P<0.001), n-LDL content in ß-carotene (-21%, P<0.001), and vitamin E (-15%, P<0.001).


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Table 3. Biochemical Parameters at Baseline, 24 Hours, 3 Days, 15 Days, and 1 Month After Endarterectomy of the 42 Patients Who Completed 12-Month Ultrasonographic Follow-Up

Associations
First, the association between the biochemical variables and the changes in vascular remodeling indexes were tested in a univariate fashion. No statistically significant association was observed between changes (from after surgery to 12 months) in both ultrasonographic indexes of vascular remodeling and baseline clinical characteristics or biochemical parameters (such as ceruloplasmin, n-LDL content in FPLPs or TBARS, plasma vitamin C, and n-LDL content in lipophilic antioxidants). Serum ceruloplasmin, n-LDL content in lipid peroxides (FPLPs and TBARS), and plasma vitamin C concentration at 24 hours and 3 days were the only biochemical parameters significantly associated with the changes in FW thickness and in percent vascular renarrowing. The higher the lipid peroxide n-LDL content, the higher the ceruloplasmin serum concentration, the lower the vitamin C plasma level, and the higher the percentage of renarrowing (Figures 1Down and 2Down). FW thickness was also positively related to n-LDL content in lipid peroxides (FPLPs: 24 hours, r=-0.60, P<0.003; 3 days, r=-0.45, P<0.04; TBARS: 24 hours, r=-0.49, P<0.03; 3 days, r=-0.49, P<0.03, respectively) and serum ceruloplasmin (24 hours, r=-0.70, P<0.005; 3 days, r=-0.61, P<0.005, respectively) and inversely related to plasma vitamin C, even if the last relation did not reach statistical significance (24 hours, r=-0.37, P<0.08; 3 days, r=-0.40, P<0.07, respectively). On the basis of these results, we investigated the association between changes in renarrowing indexes and changes in these oxidative stress parameters over a 24-hour and a 3-day period.



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Figure 1. Relation between lipid peroxide n-LDL content measured at 24 hours and 3 days of surgery and percent change of vascular renarrowing at 12 months of follow-up.



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Figure 2. Relation between ceruloplasmin (mg/L) and vitamin C (µmol/L) blood content measured at 24 hours and 3 days of surgery and percent change of vascular renarrowing at 12 months of follow-up.

Multiple regression analysis was performed as described in detail in the Methods section. The final models included only FPLPs, vitamin C, and ceruloplasmin (Table 4Down) and were adjusted for potential confounders (levels of the biochemical parameters before surgery, BMI, age, sex, ischemic heart disease, systolic blood pressure, percent stenosis before surgery, duration of surgery). A higher increase in FPLPs (ß=2.372; P<0.0001) and ceruloplasmin (ß=1.959; P<0.0001) over a 24-hour period was significantly associated with a higher percentage of vascular renarrowing at 12 months (Table 4Down). A higher decrease in vitamin C (ß=-0.536; P=0.019) over a 24-hour period was significantly associated with a higher percentage of vascular renarrowing at 12 months (Table 4Down). This model was able to explain {approx}71% (R2=0.708) of the variation in the change in percent renarrowing over the 12 months. The changes in these oxidative stress parameters over a 3-day period showed a slightly more significant association with the change in percent renarrowing over the 12-month period (R2=0.712). A weaker association was found when we used FW thickness as the dependent variable both for changes in FPLPs, ceruloplasmin, and vitamin C over a 24-hour period (R2=0.541) and for changes of the same parameters over a 3-day period (R2=0.585). This discrepancy between the two ultrasonographic indexes should be mostly attributed to the lesser sensitivity of the FW thickness as a measure of remodeling compared with the percentage of vascular renarrowing. In fact, it is well known that intimal thickness accounts for only a minor proportion of the loss in lumen diameter and that the reduction in circumferential dimension of the entire artery itself constitutes the major cause of late luminal loss.5 6 On the contrary, the percent renarrowing, which measures the degree of healing and remodeling as the percent reduction of the lumen diameter at the site of maximal narrowing, is expression not only of intima-media thickening but of vascular contraction or expansion and thus is the most appropriate index for the follow-up of lesions over a long period of time.5 6


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Table 4. Results of Multiple Regression Analysis Performed to Test the Relation Between Indexes of Oxidative Stress Measured at 24 Hours and 3 Days and the Percent Change of Vascular Renarrowing From After Surgery to 12 Months After Endarterectomy


*    Discussion
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up arrowResults
*Discussion
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In this study we found that patients undergoing elective endarterectomy have a significant increase in systemic oxidative stress. This enhanced and long-lasting systemic oxidant burden was characterized by the concomitant increase in pro-oxidants and decrease in antioxidant blood levels and is mostly attributable to the inflammatory process after surgery and plaque removal.7 9 28 29 In fact, circulating inflammatory cells such as monocytes and neutrophils adhere to the site of injury, infiltrate the vessel wall, and produce high amounts of reactive oxygen species (ROS).7 28 29 30 Concomitantly, the hepatic production of several proteins is modified with a marked increase in serum level of ceruloplasmin.31 This increase may be caused in part by monocytes, which have recently been shown to be an important source of ceruloplasmin during the inflammatory response.32 Ceruloplasmin is a multifunctional protein that behaves as an acute-phase reactant; it tends to be raised after tissue damage or inflammation and it is a marker of severity of the inflammatory process.33 Moreover, it has recently been shown that intact ceruloplasmin has an important pro-oxidant activity and stimulates cell-mediated and non–cell-mediated LDL oxidation in vitro33 34 by the Haber-Weiss reactions or by a copper ion–dependent mechanism.32 33 These two characteristics might explain the association between ceruloplasmin change over time and vascular remodeling. In addition, plaque removal might release iron and copper in catalytic forms that favor free radical reaction.35 All these events may provide a pro-oxidant environment responsible of a striking increase in local and systemic free radical generation, which affects antioxidant consumption and promotes LDL oxidation. It is generally assumed that the oxidative modification of LDL occurs primarily in the arterial intima because of the many antioxidants present in blood plasma.36 However, we cannot exclude that in the presence of conditions favoring a systemic pro-oxidant/antioxidant imbalance such as the inflammatory process after surgery with plaque removal, a significant LDL oxidation may occur also in blood plasma.

In this regard, a recent study described a transient increase in systemic oxidant burden immediately after carotid endarterectomy, but it was short-lasting and returned to baseline a few minutes after surgery.11 In contrast, our results show a more complex and long-lasting phenomenon that appears to influence the process of vascular healing and repairing.

A major finding of our study was that the increased systemic oxidative stress level detected between the first and the third days after surgery was predictive of late luminal loss. In particular, the multivariate analysis showed that changes in lipid peroxide LDL content, ceruloplasmin, and vitamin C within 24 hours and 3 days of surgery were strong predictors of change in percent renarrowing and FW thickness over the 12 months. The high interindividual variability in the oxidative stress response crucially contributes to explain most of the differences observed in the entity of healing, remodeling, and late lumen loss.

The hypothesis that an excess of systemic ROS and increased LDL oxidative modification may influence the process of vascular healing and remodeling is supported by several animal studies.7 8 9 30 It has been reported that the presence of excess ROS stimulates intimal thickening, directly promoting migration and proliferation of vascular smooth muscle cells.30 Oxidative stress also decreases the effective concentration of nitric oxide in the vessel, which has been reported to have a growth-inhibitory effect on vascular smooth muscle cells, to decrease the expression of adhesion molecules for leukocytes, and to inhibit platelet aggregation.29 Moreover, oxidative cytotoxic products produced by vessel injury may enhance the inflammatory process, impair cellular repair and accelerate cell death, and favor prostaglandin and leukotriene synthesis and platelet aggregation.7 37 38 39 40 The severity of the inflammatory stage might predict the severity of wound healing and therefore the total amount of collagen and matrix formation produced as a result of an injury.3 4 7 Interestingly, a recent study has shown that the acute inflammatory changes peak at 24 hours after endarterectomy and disappear by the fifth day.3 4 All these data strongly support our findings, which attribute to the increase in systemic oxidative stress an important role in promoting and conditioning vascular healing and renarrowing.

Among antioxidants, only plasma vitamin C was inversely and significantly related to percentage of lumen renarrowing (Figure 2Up). Our finding could be explained, considering that when free radicals are formed in an aqueous environment, such as plasma, vitamin C acts as the primary defense, whereas vitamin E is consumed only when vitamin C is depleted. Thus in the case of an inflammatory process with a short acute phase as that induced by endarterectomy, vitamin C is likely to be more important than vitamin E in reducing the inflammatory response through early free radical scavenging.41 In particular, it has recently been reported that during the inflammatory response, myeloperoxidase released from activated neutrophils generates high amounts of an aggressive ROS, mostly hypochlorous acid, which is efficiently and specifically neutralized by vitamin C.42 43 It has also been shown that vitamin C but not vitamin E or probucol protect, in vivo, endothelium from oxidized LDL–induced leukocyte adhesion and aggregate formation.44

A further confirmation of our findings comes from recent studies demonstrating that among antioxidants, only probucol45 46 and vitamin C,47 administrated before or immediately after successful percutaneous transluminal coronary angioplasty, were able to significantly attenuate restenosis.

In conclusion, our study shows that surgical procedures to remove atherosclerotic plaque, such as elective carotid endarterectomy, are followed by an acute and long-lasting systemic oxidative stress and that the higher the oxidative stress, the higher the late luminal loss. Moreover, the interindividual variability in the oxidative stress response explains most of the interindividual differences in the entity of vascular remodeling. Finally, our data provide a biological plausibility to the effectiveness of an early treatment with antioxidants, started before any invasive procedure for vascular stenosis, to prevent late renarrowing.


*    Acknowledgments
 
The skillful technical assistance given by Corrado Romano and Maria Di Riti is gratefully acknowledged.

Received September 9, 1998; accepted March 24, 1999.


*    References
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up arrowAbstract
up arrowIntroduction
up arrowMethods
up arrowResults
up arrowDiscussion
*References
 
1. Dempsey RJ, Moore RW, Cordero S. Factors leading to early recurrence of carotid plaque after carotid endarterectomy. Surg Neurol. 1995;43:278–282.[Medline] [Order article via Infotrieve]

2. Petrik PV, Gelabert HA, Moore WS, Quinones-Baldrich W, Law MM. Cigarette smoking accelerates carotid artery intimal hyperplasia in a dose-dependent manner. Stroke. 1995;26:1409–1414.[Abstract/Free Full Text]

3. Forrester JS, Fishbein M, Helfant R, Fagin J. A paradigm for restenosis based on cell biology: clues for the development of new preventive therapies. J Am Coll Cardiol. 1991;17:758–769.[Abstract]

4. Wilensky RL, Gradus-Pizlo I, Sandusky G, March KL. Vascular repair mechanisms after directional atherectomy or percutaneous transluminal coronary angioplasty in atherosclerotic rabbit iliac arteries. Am Heart J. 1996;132:13–22.[Medline] [Order article via Infotrieve]

5. Post MJ, Borst C, Kuntz RE. The relative importance of arterial remodeling compared with intimal hyperplasia in lumen renarrowing after balloon angioplasty. Circulation. 1994;89:2816–2821.[Abstract/Free Full Text]

6. Godfried SL, Deckelbaum LI. Natural antioxidants and restenosis after percutaneous transluminal coronary angioplasty. Am Heart J. 1995;129:203–210.[Medline] [Order article via Infotrieve]

7. Freyschuss A, Stiko-Rahm A, Swedenborg J, Henriksson P, Bjorkhem I, Berglund L, Nilsson J. Antioxidant treatment inhibits the development of intimal thickening after balloon injury of the aorta in the hypercholesterolemic rabbit. J Clin Invest. 1993;91:1282–1288.

8. Schneider JE, Berk BC, Gravanis MB, Santoian EC, Cipolla GD, Tarazona N, Lassegue B, King SB. Probucol decreases neointimal formation in a swine model of coronary artery balloon injury: a possible role for antioxidants in restenosis. Circulation. 1993;88:628–637.[Abstract/Free Full Text]

9. Nunes GL, Sgoutas DS, Redden RA, Sigman SR, Gravanis MB, King SB, Berk BC. Combination of vitamin C and E alters the response to coronary balloon injury in the pig. Arterioscler Thromb Vasc Biol. 1995;15:156–165.[Abstract/Free Full Text]

10. Roumen RM, Hendriks T, de Man BM, Geris RJ. Serum lipofuscin as a prognostic indicator of adult respiratory distress syndrome and multiple organ failure. Br J Surg. 1994;81:1300–1305.[Medline] [Order article via Infotrieve]

11. Soong CV, Young IS, Hood JM, Rowlands BJ, Trimble ER, Barros D’Sa AA. The generation of byproducts of lipid peroxidation following carotid endarterectomy. Eur J Vasc Endovasc Surg. 1996;12:455–458.[Medline] [Order article via Infotrieve]

12. Coghlan JG, Flitter WD, Holley AE, Norell M, Mitchell AG, Ilsley CD, Slater TF. Detection of free radicals and cholesterol hydroperoxides in blood taken from the coronary sinus of man during percutaneous transluminal coronary angioplasty. Free Radic Res Commun. 1991;14:409–417.[Medline] [Order article via Infotrieve]

13. De Servi S, Mazzone A, Ricevuti G, Fioravanti A, Bramucci E, Angoli L, Stefano G, Specchia G. Granulocyte activation after coronary angioplasty in humans. Circulation. 1990;82:140–146.[Abstract/Free Full Text]

14. Golledge J, Cuming R, Ellis M, Beattie DK, Davies AH, Greenhalgh RM. Clinical follow-up rather than duplex surveillance after carotid endarterectomy. J Vasc Surg. 1997;25:55–63.[Medline] [Order article via Infotrieve]

15. DeGroote RD, Lynch TG, Jamil Z, Hobson RW. Carotid restenosis. long-term noninvasive follow-up after carotid endarterectomy. Stroke. 1987;18:1031–1036.[Abstract/Free Full Text]

16. Bandyk DF, Moldenhauer P, Lipchik E, Schreiber E, Pohl L, Cato R, Towne JB. Accuracy of duplex scanning in the detection of stenosis after carotid endarterectomy. J Vasc Surg. 1988;8:696–702.[Medline] [Order article via Infotrieve]

17. Pignoli P, Tremoli E, Poli A, Oreste P, Paoletti R. Intimal plus medial thickness of the arterial wall: a direct measurement with ultrasound imaging. Circulation. 1986;74:1399–1406.[Abstract/Free Full Text]

18. Arbeille P, Desombre C, Aesh B, Philippot M, Lapierre F. Quantification and assessment of carotid artery lesions: degree of stenosis and plaque volume. J Clin Ultrasound. 1995;23:113–124.[Medline] [Order article via Infotrieve]

19. Mezzetti A, Lapenna D, Pierdomenico SD, Calafiore AM, Costantini F, Riario-Sforza G, Pierdomenico SD, Costantini F, Neri M, Cuccurullo F. Vitamins E, C, and lipid peroxidation in plasma and arterial tissue of smokers and non-smokers. Atherosclerosis. 1995;112:91–99.[Medline] [Order article via Infotrieve]

20. Pierdomenico SD, Costantini F, Bucci A, De Cesare D, Cuccurullo F, Mezzetti A. Low-density lipoprotein oxidation and vitamins E and C in sustained and white coat hypertension. Hypertension. 1998;31:621–626.[Abstract/Free Full Text]

21. Costantini F, Pierdomenico SD, De Cesare D, De Remigis P, Cazzolato G, Bittolo-Bon G, Nubile G, Guagnano MT, Sensi S, Cuccurullo F, Mezzetti A. Effect of thyroid function on low density lipoprotein oxidation. Arterioscler Thromb Vasc Biol. 1998;17:732–737.

22. Chung BH, Segrest JP, Ray MJ, Brunzell JD, Hokanson JE, Krauss RM, Beaudrie K, Cone JT. Single vertical spin density gradient ultracentrifugation. Methods Enzymol. 1986;128:181–209.[Medline] [Order article via Infotrieve]

23. Lowry OH, Rosenbrough NJ, Farr A, Randall RJ. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951;193:265–275.[Free Full Text]

24. Esterbauer H, Striegl G, Puhl H, Rotheneder M. Continuous monitoring of in vitro oxidation of human low density lipoprotein. Free Radic Res Commun. 1989;6:67–75.[Medline] [Order article via Infotrieve]

25. Esterbauer H, Dieber-Rotheneder M, Waeg G, Striegl G, Jurgens G. Biochemical, structural and functional properties of oxidized low-density-lipoprotein. Chem Res Toxicol. 1990;3:77–92.[Medline] [Order article via Infotrieve]

26. Kikugawa K. Fluorescent products derived from the reaction of primary amines and components in peroxidized lipids. Adv Free Radic Biol Med. 1986;2:389–417.

27. Dillard CJ, Tappel AL. Fluorescent products of lipid peroxidation. Methods Enzymol. 1984;105:337–348.[Medline] [Order article via Infotrieve]

28. Baxter CR. Immunologic reactions in chronic wounds. Am J Surg. 1994;167(suppl 1A):12S–14S.

29. Gong KW, Zhu GY, Wang LH, Tang CS. Effect of active oxygen species on intimal proliferation in rat aorta after arterial injury. J Vasc Res. 1996;33:42–46.[Medline] [Order article via Infotrieve]

30. Berliner JA, Navab M, Fogelman AL, Frank JS, Demer LL, Edwards PA, Watson AD, Lusis AJ. Atherosclerosis: basic mechanisms: oxidation, inflammation, and genetics. Circulation. 1995;91:2488–2496.[Abstract/Free Full Text]

31. Rosenson RS. Myocardial injury: the acute phase response and lipoprotein metabolism. J Am Coll Cardiol. 1993;22:933–940.[Abstract]

32. Ehrenwald E, Fox PL. Role of endogenous ceruloplasmin in low density lipoprotein oxidation by human U937 monocytic cells. J Clin Invest. 1996;97:884–890.[Medline] [Order article via Infotrieve]

33. Fox PL, Mukhopadhyay C, Ehrenwald E. Structure, oxidant activity, and cardiovascular mechanisms of human ceruloplasmin. Life Sci. 1995;56:1749–1758.[Medline] [Order article via Infotrieve]

34. Ehrenwald E, Chisolm GM, Fox PL. Intact human ceruloplasmin oxidatively modifies low density lipoprotein. J Clin Invest. 1994;93:1493–1501.

35. Evans PJ, Smith C, Mitchinson MJ, Halliwell B. Metal ion release from mechanical-disrupted human arterial wall: implications for the development of atherosclerosis. Free Radic Res Commun. 1995;23:465–469.

36. Witztum JL. The oxidation hypothesis of atherosclerosis. Lancet. 1994;344:793–795.[Medline] [Order article via Infotrieve]

37. Lucy JA, Dingle JT. Fat-soluble vitamins and biological membranes. Nature. 1964;204:156–160.[Medline] [Order article via Infotrieve]

38. Halliwell B, Gutteridge JMC. Oxygen toxicity, oxygen radicals, transition metals and disease. Biochem J. 1984;219:1–14.[Medline] [Order article via Infotrieve]

39. Toivanen JL. Effects of selenium, vitamin E and vitamin C on human prostacyclin and thromboxane synthesis in vitro. Prostaglandins Leukot Med. 1987;26:265–280.[Medline] [Order article via Infotrieve]

40. Redanna P, Whelan J, Burgess JR, Eskew ML, Hildenbrandt G, Zarkower A. Vitamin E and selenium on arachidonic acid oxidation by way of the 5-lipoxygenase pathway. Ann N Y Acad Sci. 1989;570:136–145.[Medline] [Order article via Infotrieve]

41. Frei B. Ascorbic acid protects lipids in human plasma and low-density lipoprotein against oxidative damage. Am J Clin Nutr. 1991;54(suppl 6):1113S–1118S.

42. Hu ML, Louie S, Cross CE, Motchnik P, Halliwell B. Antioxidant protection against hypochlorous acid in human plasma. J Lab Clin Med. 1993;121:257–262.[Medline] [Order article via Infotrieve]

43. Eaton JW. Defenses against hypochlorous acid: parrying the neutrophil’s rapier thrust. J Lab Clin Med. 1993;121:197–198.[Medline] [Order article via Infotrieve]

44. Lehr HA, Frei B, Olofsson AM, Carew TE, Arfors KE. Protection from oxidized LDL-induced leukocyte adhesion to microvascular and macrovascular endothelium in vivo by vitamin C but not vitamin E. Circulation. 1995;91:1525–1532.[Abstract/Free Full Text]

45. Yokoi H, Daida H, Kuwabara Y, Nishikawa H, Takatsu F, Tomihara H, Nakata Y, Kutsumi Y, Ohshima S, Nishiyama S, Seki A, Kato K, Nishimura S, Kanoh T, Yamaguchi H. Effectiveness of an antioxidant in preventing restenosis after percutaneous transluminal coronary angioplasty: the probucol angioplasty restenosis trial. J Am Coll Cardiol. 1997;30:855–862.[Abstract]

46. Tardif JC, Cote G, Lesperance J, Bourassa M, Lambert J, Doucet S, Bilodeau L, Nattel S, de Guise P. Probucol and multivitamins in the prevention of restenosis after coronary angioplasty: multivitamins and probucol study group. N Engl J Med. 1997;337:365–372.[Abstract/Free Full Text]

47. Tomoda H, Yoshitake M, Morimoto K, Aoki N. Possible prevention of postangioplasty restenosis by ascorbic acid. Am J Cardiol. 1996;78:1284–1286[Medline] [Order article via Infotrieve]




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