[Immunohistochemical detection of altered low density lipoprotein (ox-LDL) in the vessel walls of patients with giant cell arteritis]. / Immunhistochemischer Nachweis veränderter Low-density-Lipoproteine (ox-LDL) in der Gefässwand bei Patienten mit Arteriitis temporalis.

BACKGROUND AND PURPOSE: Recent data indicate that lipid peroxidation is implicated in the pathogenesis of giant cell arteritis with a close anatomic relationship between reactive oxygen species and oxidatively injured vascular tissue. PATIENTS AND METHODS: Immunohistochemistry utilizing anti-ox-LDL was performed on paraffin sections of isolated temporal arteries obtained from patients (n=23) suspected of having temporal arteritis. Enrichment as well as staining intensity of ox-LDL in vascular tissue was analysed by digital image planimetry. RESULTS: Temporal arteries with biopsy proven temporal arteritis (n=11) presented with significantly higher enrichment of ox-LDL in the intima (16.9+/-4.2% vs. 11.25+/-2.3%; p<0.01) and mean (9.6+/-2.4% vs. 6.75+/-1.8%; p<0.01) as compared to healthy controls. Comparable results for the staining intensity were found in the intimal (2.8+/-0.5 eU vs. 1.7+/-0.4 eU; p<0.01) and medial layer (1.55+/-0.5 eU vs. 1.04+/-0.6 eU; p<0.01) of diseased patients compared to controls. CONCLUSIONS: Accumulation of ox-LDL in the intimal layer, especially at the intima-media-border, was closely related to disruption of the elastica interna and adjacent vascular tissue, presumably contributing to the underlying process of intimal hyperplasia through unimpeded migration of smooth muscle and accumulation inflammatory cells.

Enhanced accumulation of the isoprostane, 8-epi-PGF2 alpha, in human aortic and pulmonary valves of patients with coronary heart disease.

The aim of the present study was to investigate whether the isoprostane 8-epi-PGF2 alpha differently accumulates in semilunar valves of patients suffering from coronary heart disease (CHD, n = 19) as compared to valves from healthy heart donors (controls, n = 6). Sections from isolated aortic and pulmonary valves were analyzed by semiquantitative immunohistochemistry. The 8-epi-PGF2 alpha-content was determined by using a specific radioimmunoassay. The accumulation of 8-epi-PGF2 alpha in both valves was higher in CHD-patients in comparison to controls (Aortic valves: 36.49 +/- 11.26% vs. 15.78 +/- 3.04%; pulmonary valves: 46.79 +/- 9.80% vs. 14.99 +/- 3.57%). The results from the radioimmunoassay revealed comparable findings in both groups (CHD vs. controls: 395.95 +/- 86.09 vs. 139.50 +/- 47.46 pg/mg protein in the aortic valves and 430.47 +/- 76.30 vs. 147.33 +/- 53.84 pg/mg protein in pulmonary valves). Pulmonary valves seem to be more susceptible to oxidative stress than aortic valves as evidenced by a higher accumulation of 8-epi-PGF2 alpha in CHD patients. Considering the data presented in this study, we suggest that 8-epi-PGF2 alpha is a valuable indicator of oxidative injury in human semilunar valves.

The isoprostane 8-epi-PGF(2alpha) is a valuable indicator of oxidative injury in human heart valves.

To date, little information is available concerning oxidative injury in human cardiac valves. Therefore, we sought to investigate whether the isoprostane, 8-epi-PGF(2alpha), a novel oxidative stress marker, is localized in aortic and pulmonary valves derived from explanted hearts of patients suffering from idiopathic dilative cardiomyopathy (IDC). By using semiquantitative immunohistochemistry, we demonstrated that 8-epi-PGF(2alpha) is localized in both valves with pulmonary valves accumulating more of this isoprostane compared to aortic valves (36.69+/-12.04% vs. 31.54+/-11.49%, P<.05). These results were confirmed by a radioimmunoassay (RIA) analysis showing a similar, but not significant, difference between the two valves (288.50+/-72.18 pg/mg protein in the pulmonary valves and 267.30+/-58.77 pg/mg protein in aortic valves, P=.09). Considering the data presented in this study, we suggest that 8-epi-PGF(2alpha) is a valuable indicator of oxidative injury in human semilunar valves.

Angiogenesis stimulation in explanted hearts from patients pre-treated with intravenous prostaglandin E(1).

BACKGROUND: Prostaglandin E(1) (PGE(1)) is a potent vasodilator and induces angiogenesis in animal tissues. Previous clinical studies demonstrated that PGE(1) improves hemodynamic parameters in patients with heart failure listed for heart transplantation (HTX). Therefore, we designed a retrospective immunohistochemistry study to investigate various markers of angiogenesis using hearts explanted from PGE(1)-treated patients with idiopathic dilated cardiomyopathy (IDCM). METHODS AND RESULTS: We investigated neovascularization in 18 hearts explanted from patients with IDCM: 9 patients received treatment with chronic infusions of PGE(1) for end-stage heart failure before HTX, whereas the remaining patients with IDCM did not receive PGE(1) and served as controls. We used immunoreactivity against CD34, von Willebrand factor (vWf), vascular endothelial growth factor (VEGF), and MIB-1 (Ki-67) to quantify angiogenesis, and used sirius red staining to determine the degree of fibrosis. Compared with the control group, PGE(1)-treated patients had significantly more CD34-, vWf- and MIB-1-positive cells in the sub-endocardium, myocardium and sub-epicardium (p < 0.01). The degree of fibrosis in the hearts of PGE(1)-treated patients was significantly lower than in control patients (p < 0.05), but we did not see any difference in the percentage of muscle mass. Finally, throughout the ventricles, we found significantly more VEGF-positive capillaries in the PGE(1) group (p < 0.0001). CONCLUSIONS: The data suggest that PGE(1) could be a potent inducer of angiogenesis and the angiogenic factor VEGF, and could cause reduced fibrosis in the failing human heart.

Accumulation of oxidized LDL in human semilunar valves correlates with coronary atherosclerosis.

OBJECTIVE: Recent data indicate that oxidized low-density lipoprotein (ox-LDL) has several proatherogenic effects, e.g. induction of macrophage chemoattractants, adhesion molecules, cytokines, type-1 plasminogen activator inhibitor and platelet-derived growth factor A-chain by smooth muscle cells. Therefore, ox-LDL has been utilized as a marker of oxidative modification of proteins in atherosclerosis. Because heart valves consist of smooth muscle cells, fibroblasts and endothelial cells, and because valvular disease and coronary atherosclerosis could result from similar biological processes, we investigated ox-LDL accumulation in isolated aortic and pulmonary valves and coronary arteries from patients with angiographically proven coronary heart disease (CHD, n = 19), patients with idiopathic congestive heart failure (IDCM = idiopathic dilated cardiomyopathy, n = 20), and transplant donors. METHODS: Masson-Goldner staining and immunohistochemistry utilizing anti ox-LDL and CD68 were performed on paraffin sections of freshly isolated semilunar valves. Data were analyzed by digital image planimetry and by visual scoring of staining intensity. RESULTS: Ox-LDL immunoreactivity was identified in the vascular aspect of the attachment line, in the deep valve stroma, and in the ventricular and vascular endothelium of the semilunar valves, colocalizing with macrophages. Valvular ox-LDL area was significantly increased in CHD-patients (P < 0.03) and IDCM-patients (P < 0.04) compared with controls. More ox-LDL was accumulating in the pulmonary valves than in the aortic valves (P = 0.04) as assessed by area and staining intensity. Valvular ox-LDL area in pulmonary valve and aortic valve was significantly correlated with ox-LDL accumulation in the intimal layer (P < 0.001) and medial layer (P < 0.001) of coronary arteries from the same patients. CONCLUSION: The data suggest that the biological process leading to ox-LDL accumulation in coronary atherosclerosis also involves heart valves. Therefore, accumulation of the oxidative stress marker ox-LDL in heart valves illustrates atherosclerosis as an additional mechanisms accelerating valvular degeneration in these patients.

The isoprostane, 8-epi-PGF2 alpha, is accumulated in coronary arteries isolated from patients with coronary heart disease.

OBJECTIVE: In the present study we wanted to know whether 8-epi-PGF2 alpha, which belongs to the class of isoprostanes formed by free radical-mediated peroxidation of arachidonic acid and arachidonyl-containing phospholipids, is enriched in isolated coronary arteries of patients suffering from coronary heart disease (CHD, n = 23) who received allograft heart transplants as compared to vessels derived from patients with dilative cardiomyopathy (CMP, n = 19) or from healthy heart donors (controls, n = 6). METHODS: Sections from the isolated coronary arteries were analysed by semiquantitative immunohistochemistry by determining the area and intensity of positive reaction for 8-epi-PGF2 alpha in the vascular intima and media. In addition, the 8-epi-PGF2 alpha content was determined using a specific immunoassay after extraction and purification. RESULTS: The immunohistochemical results indicated that 8-epi-PGF2 alpha is significantly enriched in arteries from patients suffering from CHD as compared to CMP (P < 0.0001). In controls, significantly less immunostaining was observed. Furthermore, a significant positive correlation between semiquantitative immunohistochemistry and radioimmunological determination was observed too. CONCLUSIONS: From our findings we conclude that 8-epi-PGF2 alpha is especially accumulated in coronary arteries from CHD patients and therefore is likely to be involved in atherogenesis.

Spectrophotometric determination of acidity constants of some anthraquinones and anthrones in methanol-water mixtures.

The acidity constants of some synthetic derivatives of 9,10-anthraquinone and 9-anthrone in methanol-water mixtures at 25 degrees have been determined spectrophotometrically. A linear reverse relationship is observed between pK(a1) of all acids and the mole fraction of methanol. The influence of substituents in the molecular structure on the ionization constants is discussed.