Determinative Role of Peroxidized Low-Density Lipoprotein in Myocardial Thromboxane Synthesis during Pacing-Induced Ischaemia in Humans

1998 ◽  
Vol 94 (1) ◽  
pp. 29-34 ◽  
Author(s):  
Hsiu-Ching Hsu ◽  
Ming-Fong Chen ◽  
Chii-Ming Lee ◽  
Yuan-Teh Lee

1. Myocardial thromboxane A2 production increases in patients with pacing-induced ischaemia and correlates with a decrease in myocardial lactate extraction. The release of myocardial thromboxane A2 before any lactate production was observed in patients with unstable angina. This study was proposed to clarify whether the early thromboxane A2 release contributed to the ongoing myocardial ischaemia and to determine which metabolites can be attributed to the thromboxane A2 release. Thirty-five patients with chest pain and positive treadmill exercise test underwent atrial pacing to the predicted maximal heart rate. The pacing was maintained at this peak rate for 10 min, then ceased. Blood samples of the ascending aorta and coronary sinus were drawn simultaneously at rest, at 2 and 10 min of peak-pacing, and 5 and 10 min after termination of the pacing; samples were used for analyses of lipid profiles, prostacyclin, thromboxane A2, lactate and lipid peroxides on plasma and low-density lipoprotein particles. 2. Twenty out of 35 patients who displayed pacing-induced ischaemia were documented by electrocardiographic evidence of ST depression >2 mm developing after 2 min of peak-pacing [ischaemic group, STΔ(+)]. They had (i) negative fractional lactate extraction; (ii) pacing-induced decreases of plasma thromboxane A2 levels in the coronary sinus blood (564 ± 57 versus 479 ± 47 ng/l, P < 0.05) at 2 min of peak-pacing; the data increased at 10 min of peak-pacing (564 ± 57 versus 620 ± 60 ng/l, P < 0.05), then returned to baseline levels at 5 and 10 min post-pacing; (iii) significantly increased lipid peroxides on low-density lipoprotein of the coronary sinus blood at 2 and 10 min of peak-pacing (each P < 0.001), as well as at 5 min post-pacing (P < 0.05); (iv) significant correlation between thromboxane A2 levels and lipid peroxides on low-density lipoprotein of the coronary sinus blood samples. 3. In STΔ(+) patients, myocardial thromboxane synthesis changed before lactate production and correlated with the increase of lipid peroxides on low-density lipoprotein of the coronary venous blood. This implies that lipid peroxides on low-density lipoprotein participate in thromboxane production and play a determinative role in pacing-induced ischaemia.

1984 ◽  
Vol 51 (02) ◽  
pp. 186-188 ◽  
Author(s):  
A Szczeklik ◽  
R J Gryglewski ◽  
K Sladek ◽  
E Kostka-Trąbka ◽  
A Żmuda

SummaryDihomo-γ-linolenic acid (DHLA), a precursor of monoenoic anti-aggregatory prostaglandins (PGE1, PGD2), was administered for 4 weeks in a daily dose of 1.0 g into 33 patients with atherosclerosis on a basis of a double-blind trial. Comparison of treatment and placebo groups revealed elevation of DHLA in red cell lipids in DHLA-treated subjects. No differences, however, between the two groups could be observed in platelet aggregability, thromboxane A2 generation by platelets, serum cholesterol, PGE1 and PGE2 levels, and in inhibitory activity of low-density lipoproteins against prostacyclin synthetizing system in arteries. The dietary supplementation used did not lead to distinct antithrombotic effects.


2011 ◽  
Vol 59 (4) ◽  
pp. 445-454 ◽  
Author(s):  
Ewa Skotnicka ◽  
Zbigniew Muszczyński ◽  
Maria Suska

Blood samples were taken from 12 goats during the periparturient period (4 and 1 weeks before and 2, 10 and 30 days after delivery), and from 10 nonpregnant goats. The following variables were determined: total lipids (TL), triacylglycerol (TG), total cholesterol (TCH) and high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol fractions. One week before delivery TL (2.32 ± 0.12 g/l, P ≤ 0.05), TG (0.32 ± 0.16 mmol/l, P ≤ 0.001) and TCH concentrations (1.65 ± 0.42 mmol/l, P ≤ 0.05) were significantly increased as compared to non-pregnant goats (2.08 ± 0.28 g/l, 0.15 ± 0.05 mmol/l, 1.38 ± 0.19 mmol/l, respectively). After delivery, the concentrations of TL, TG, TCH and HDL decreased significantly. The lowest TG concentration was observed 2 days after delivery (0.18 ± 0.02 mmol/l), while TL (1.73 ± 0.21 g/l), TCH (0.95 ± 0.21 mmol/l) and HDL (0.74 ± 0.16 mmol/l) reached the lowest level 10 days after delivery. Two days after delivery a significant increase of LDL concentration was observed (0.38 ± 0.04 mmol/l); however, ten days after delivery a threefold decrease was shown in the LDL concentration (0.12 ± 0.04 mmol/l). A month after delivery all the variables studied reached levels similar to those measured in non-pregnant goats.


1993 ◽  
Vol 294 (3) ◽  
pp. 829-834 ◽  
Author(s):  
M I Mackness ◽  
C Abbott ◽  
S Arrol ◽  
P N Durrington

1. The oxidation of low-density lipoprotein (LDL) is believed to play a central role in atherogenesis. We have compared the effect of antioxidant vitamins and high-density lipoprotein (HDL) on the Cu(2+)-catalysed oxidation of LDL. 2. Antioxidant vitamin supplementation significantly reduced conjugated diene formation but did not affect the formation of lipid peroxides. 3. Conversely, HDL did not affect conjugated diene formation but inhibited the formation of lipid peroxides by up to 90%. 4. The inhibition by HDL of lipid peroxide formation in oxidized LDL was dependent on the concentration of HDL and was not due to HDL chelating Cu2+. 5. Large interindividual variations in the inhibition of lipid peroxide formation by autologous HDL were evident, which were related to the rate of lipid peroxide generation in the LDL. 6. We conclude that HDL is a powerful antioxidant or more probably inhibitor of LDL oxidation in vitro and may play an important role in vivo in preventing atherosclerosis by inhibiting LDL oxidation in the artery wall.


2017 ◽  
Vol 4 (1) ◽  
pp. 39-44
Author(s):  
Ni Made Restina Juliani ◽  
I Putu Oka Dharmawan ◽  
Putu Ayu Parwati

Introduction: Low Density Lipoprotein (LDL) is a type of low-density lipoprotein and the most widely transported cholesterol in the body. Increased levels of LDL in the body can be affected by genetics, age, gender, obesity, physical activity, lifestyle, drug consumption and smoking. Substances in a cigarette can cause an increase of LDL levels. Increased of LDL cholesterol levels can cause Coronary Heart Disease (CHD). The purpose of this research is to know the description of Low Density Lipoprotein (LDL) levels on smoker and non-smoker adolescent in Buyan Hamlet, Pancasari Village, Sukasada District, Buleleng Bali. Method: The type of this research is descriptive. This research was conducted in April-May 2017, which used fasting blood samples of 42 respondents. Result: From the average result of LDL level in smoker adolescent that is 134,91 mg/dL higher than the average of LDL level in non-smoker adolescent that is 74,90 mg/dL. The result of LDL cholesterol levels was determined by 21 smoker adolescent respondents with the close to optimal category (100-129 mg/dL) as many as 9 people (42,8%), and 12 people (57,3%) with worry category (130-159 mg/dL). Whereas in 21 non-smoker adolescent respondents obtained  result of LDL cholesterol level test with optimal category (<100 mg/dL) counted 18 people (87,71%) and 3 person (14,30%) with close to optimal category (100-129 mg/dL). Discussion: Based on the results of this research can be concluded that in smoker adolescent obtained LDL levels with close to optimal category and worrying whereas in non-smoker adolescents obtained LDL levels in the optimal category and close to optimal.


2014 ◽  
Vol 32 (7) ◽  
pp. 1328-1334 ◽  
Author(s):  
Motunrayo G Akande ◽  
Yusuf O Aliu ◽  
Suleiman F Ambali ◽  
Joseph O Ayo

The aim of this study was to investigate the effects of taurine (TA) on serum lipid profiles following chronic coadministration of chlorpyrifos (CP) and lead acetate (Pb) in male Wistar rats. Fifty rats randomly distributed into five groups served as subjects. Distilled water (DW) was given to DW group, while soya oil (SO; 1 mL kg−1) was given to SO group. The TA group was treated with TA (50 mg kg−1). The CP + Pb group was administered sequentially with CP (4.25 mg kg−1; 1/20th median lethal dose (LD50)) and Pb at 233.25 mg kg−1 (1/20th LD50), while the TA + CP + Pb group received TA (50 mg kg−1), CP (4.25 mg kg−1), and Pb (233.25 mg kg−1) sequentially. The treatments were administered once daily by oral gavage for 16 weeks. The rats were euthanised, and the blood samples were collected at the termination of the study. Sera obtained from the blood samples were analyzed for total cholesterol, high-density lipoprotein cholesterol, triglycerides, and malondialdehyde, and also the activities of serum antioxidant enzymes including superoxide dismutase, catalase and glutathione peroxidase were analyzed. The low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, and atherogenic index were calculated. The results showed that CP and Pb induced alterations in the serum lipid profiles and evoked oxidative stress. TA alleviated the disruptions in the serum lipid profiles of the rats partially by mitigating oxidative stress. It was concluded that TA may be used for prophylaxis against serum lipid disorders in animals that were constantly co-exposed to CP and Pb in the environment.


Author(s):  
Nishith Patel ◽  
Bernard F Rocks ◽  
S Andrew Iversen

A competitive silver-enhanced gold-labelled immunoassay has been developed for the direct measurement of low density lipoprotein (LDL) in whole blood. Immobilized LDL and sample LDL compete for added antibody. Quantitation of the bound antibody/antigen complex is achieved by the addition of gold-labelled antiimmunoglobulin G followed by enhancement of absorbance by addition of silver ions. Whole-blood samples from fasting patients were assayed directly for LDL by the procedure and the corresponding plasma samples were assayed for total cholesterol, high density lipoprotein and triglycerides followed by the indirect calculation of LDL cholesterol. The correlation between the two methods was good (r = 0·82) and the SEGLISA exhibited good precision.


FEBS Letters ◽  
1999 ◽  
Vol 459 (1) ◽  
pp. 47-50 ◽  
Author(s):  
Riccardo Albertini ◽  
Giancarlo De Luca ◽  
Giuseppina Palladini ◽  
Alberto Passi ◽  
Gian Vico Melzi d'Eril ◽  
...  

2008 ◽  
Vol 33 (3) ◽  
pp. 489-500 ◽  
Author(s):  
Antonio S. Santo ◽  
Ariana M. Cunningham ◽  
Sofiya Alhassan ◽  
Richard W. Browne ◽  
Harold Burton ◽  
...  

The traditional lipid profile compared with nuclear magnetic resonance (NMR) may underestimate the risk for cardiovascular disease and may explain some of the discrepancies in results between studies analyzing the salubrious effects of soy. Our purpose was to compare the traditional lipid profile with NMR quantification of the number of lipoprotein particles, subclasses, and diameters or sizes in 30 sedentary males, between 18 and 30 years of age, consuming 1 of the following 3 supplements daily for 28 days: milk protein (Milk), isoflavone-poor soy protein (Soy–), or isoflavone-rich soy protein (Soy+). The study used a double-blind, parallel-arm design with random assignment to 1 of the 3 protein supplement groups. Fasting EDTA blood samples were collected at baseline and after 28 days of supplementation and analyzed for the number and size of very low-density lipoprotein (VLDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) particles, respectively. Fasting serum samples were analyzed for concentrations of total cholesterol (TC), LDL cholesterol (LDL-C), total HDL cholesterol (HDL-C), HDL2-C, HDL3-C, triglycerides (TGs), free fatty acids (FFAs), and glucose. Fasting heparin blood samples were collected at baseline and after supplementation and analyzed for apolipoproteins A-I, A-II, B, C-II, C-III, and E, as well as hepatic and lipoprotein lipase concentrations. HDL3-C increased by 47.2% after Soy+ supplementation and hepatic lipase decreased 19.2% after Soy– supplementation (p < 0.05). HDL-C and apolipoproteins A-I and A-II were found to increase in all 3 groups (p < 0.05). Results support that NMR analysis of lipoprotein particle number and size are not more sensitive to the effect of soy protein on CVD risk compared with the traditional lipid profile. Furthermore, the lack of isoflavones in soy protein seems to have a deleterious effect on hepatic lipase.


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