| 1. |
- Sarabi, Mahziar, et al.
(författare)
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Relationships between Endothelium-Dependent Vasodilation, Serum Vitamin E and Plasma Isoprostane 8-Iso-PGF2alpha Levels in Healthy Subjects
- 1999
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Ingår i: Journal of Vascular Research. - : S. Karger AG. - 1018-1172 .- 1423-0135. ; 36:6, s. 486-491
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Tidskriftsartikel (refereegranskat)abstract
- Due to the reported associations between a low intake of vitamin E and atherosclerosis on one hand, and between endothelial dysfunction and atherosclerosis on the other hand, we investigated the relationship between endothelium-dependent vasodilation and serum levels of vitamin E (alpha- and gamma-tocopherol) as well as the lipid peroxidation markers malondialdehyde and 8-iso-PGF(2alpha) in a healthy population. Healthy subjects (31 men and 25 women), aged between 20 and 69 years, underwent measurements of forearm blood flow (FBF) at rest and during local infusion of 2 and 4 microg/min of methacholine (Mch, to evaluate endothelium-dependent vasodilation) and 5 and 10 microg/min of sodium nitroprusside (SNP, to evaluate endothelium-independent vasodilation, and during reactive hyperemia using venous occlusion plethysmography. Serum alpha-tocopherol concentration was significantly related to the index of endothelial function (r = 0.46, p < 0.01), defined as the ratio between the maximal dilatations during Mch and SNP infusions. Serum gamma-tocopherol levels were positively related to the maximal FBF during reactive hyperemia (r = 0.54, p < 0.01) in women only. Furthermore, in women only, plasma 8-iso-PGF(2alpha) levels were inversely related to the relative increases in FBF during both Mch and SNP infusions (r = -0.58 and r = -0.59, p < 0.01 for both). The results show a relationship between the levels of alpha-tocopherol and endothelial vasodilatory function, suggesting a beneficial role for this potent lipid-soluble antioxidant also in a population sample of apparently healthy subjects. Furthermore, in women, the accumulation of lipid peroxidation products such as 8-iso-PGF(2alpha) seems to be associated with an impaired vasodilation in general.
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| 2. |
- Steer, Peter, et al.
(författare)
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Cardiac and vascular structure and function are related to lipid peroxidation and metabolism
- 2002
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Ingår i: Lipids. - : Wiley. - 0024-4201 .- 1558-9307. ; 37:3, s. 231-236
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Tidskriftsartikel (refereegranskat)abstract
- The present study investigated possible relationships between left ventricular mass, intima-media thickness of the carotid artery (IMT), total arterial compliance, and lipid status in a population sample of 58 apparently healthy subjects aged 20 to 69. By stepwise multiple regression analysis, including age, blood pressure, and smoking, left ventricular mass index, measured by M-mode echocardiography, increased by 13.0 g/m2 for each 1 standard deviation (SD = 0.11 microM, r = 0.60, P< 0.01) increase in plasma malondialdehyde and 9.50 g/m2 per SD increase in plasma 8-iso-prostaglandin F2alpha in women only (SD = 8.88 ng/L, r = 0.44, P = 0.01). Each 1-SD (SD = 0.27 g/L) increase in apolipoprotein B was associated with a 63 microm increase in IMT (r = 0.47, P = 0.014) and a 0.27 mL/min/m2/mm Hg (r = -0.60, P < 0.01) decrease in stroke index/pulse pressure ratio, reflecting total arterial compliance in women. In men, each 1-SD increase in the proportion of stearic acid (18:0) in serum cholesterol esters (SD = 0.12 percent units) reduced the transmitral E/A ratio, measured by Doppler echocardiography, reflecting left ventricular diastolic function, by 0.10 units (r = -0.29, P < 0.05). Thus, important cardiovascular characteristics, such as left ventricular mass, left ventricular diastolic function, carotid IMT, and total arterial compliance, were independently predicted by indices of lipid metabolism and peroxidation in apparently healthy subjects.
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| 3. |
- Steer, Peter, et al.
(författare)
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Endothelial vasodilatory function is predicted by circulating apolipoprotein B and HDL in healthy humans
- 2002
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Ingår i: Lipids. - : Wiley. - 0024-4201 .- 1558-9307. ; 37:12, s. 1135-1140
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Tidskriftsartikel (refereegranskat)abstract
- Endothelium-dependent vasodilation (EDV), LDL particle size, and antibodies against oxidized LDL (oxLDLab) have been shown to be related to the development of atherosclerosis and cardiovascular disease. In this study, we investigated whether LDL particle size, oxLDLab, apolipoproteins, and lipoproteins are related to endothelial vasodilatory function in a population sample of 58 apparently healthy subjects aged 20 to 69 yr. EDV and endothelium-independent vasodilation (EIDV) were studied in the forearm during local administration of methacholine chloride (2 and 4 microg/min) or sodium nitroprusside (5 and 10 microg/min). Forearm blood flow was determined with venous occlusion plethysmography. In multiple stepwise regression analyses, neither oxLDLab nor small LDL particles were significantly predictive of endothelial vasodilatory function. Instead, a high level of apolipoprotein B (apoB) was an independent predictor of both attenuated EDV and EIDV (r = -0.43, P < 0.01, and r = -0.34, P < 0.05, respectively). HDL cholesterol, on the other hand, was the only lipid variable that was significantly related to the EDV to EIDV ratio, an index of endothelial vasodilatory function (r = 0.35, P < 0.01). The inverse associations between apoB and both EDV and EIDV indicate that apoB might be an early marker of structural vascular changes in healthy subjects, whereas HDL seems to be more specifically related to endothelial vasodilatory function.
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| 4. |
- Steer, Peter, et al.
(författare)
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Vitamin C, diclophenac and L-arginine protect endothelium-dependent vasodilation against elevated circulating fatty acid levels in humans
- 2003
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Ingår i: Atherosclerosis. - 0021-9150 .- 1879-1484. ; 168:1, s. 65-72
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Tidskriftsartikel (refereegranskat)abstract
- An acute elevation of circulating non-esterified fatty acids (NEFAs) has previously been shown to impair endothelium-dependent vasodilation (EDV). In this study, we investigated if local administration of vitamin C (n=8, 18 mg/min), L-arginine (n=8, 12.5 mg/min), or the cyclooxygenase (COX) inhibitor diclophenac (n=8, 0.5 mg/min) can counteract the endothelial dysfunction seen during infusion of Intralipid plus heparin (n=10). EDV and endothelium-independent vasodilation (EIDV) were studied in the forearm after local administration of methacholine chloride (Mch; 2 and 4 microg/min) and sodium nitroprusside (SNP; 5 and 10 microg/min). Forearm blood flow (FBF) was determined with venous occlusion plethysmography. Intralipid and heparin increased circulating NEFA levels sevenfold and impaired EDV (P<0.001 vs baseline). Concomitant administration of L-arginine or diclophenac abolished the NEFA-induced impairment in EDV. Concomitant vitamin C administration actually improved EDV (P<0.05 vs baseline). NEFA elevation increased EIDV (P<0.01), but this effect was not significant after L-arginine or diclophenac infusions. In conclusion, an acute elevation of circulating NEFAs led to impaired EDV. Administration of L-arginine, vitamin C or COX inhibition abolished this effect, suggesting that NEFAs might interact with endothelial vasodilatory function through multiple mechanisms.
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