Reference intervals for plasma apolipoprotein B determined with a standardized commercial immunoturbidimetric assay: results from the Framingham Offspring Study

Abstract We evaluated a commercially available, standardized immunoturbidimetric assay for apolipoprotein (apo) B, the protein constituent of low-density lipoprotein (LDL), to establish reference ranges for men and women, and to determine the concentrations associated with increased risk of coronary heart disease (CHD). The between-run CV for assay of a normal-concentration control for this assay was 6.60%. The mean (+/-SD) apo B concentration was 1.03 +/- 0.24 g/L in 1880 men, significantly higher than the mean for 1944 women (0.96 +/- 0.26 g/L) participating in cycle 4 of the Framingham Offspring Study (P<0.001). An apo B value of 1.20 g/L corresponded roughly to the 75th percentile in men, similar to an LDL cholesterol concentration of 1.60 g/L, and subjects with concentrations greater than this were significantly more likely to have CHD than subjects with apo B concentrations less than 1.00 g/L, the approximate 50th percentile (P<0.05 in men and P<0.001 in women).

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Biological variability in serum vitamin E concentrations: relation to serum lipids

Clinical Chemistry ◽

10.1093/clinchem/42.11.1824 ◽

1996 ◽

Vol 42 (11) ◽

pp. 1824-1831 ◽

Cited By ~ 20

Author(s):

M Maes ◽

S Weeckx ◽

A Wauters ◽

H Neels ◽

S Scharpé ◽

...

Keyword(s):

Vitamin E ◽

Serum Lipids ◽

Low Density Lipoprotein ◽

Serum Vitamin ◽

Density Lipoprotein ◽

Low Density Lipoprotein Cholesterol ◽

Apo B ◽

Positive Time ◽

Index Of Individuality ◽

The Mean

Abstract The components of biological variation in serum vitamin E in relation to serum cholesterol, triglycerides, high- and low-density lipoprotein cholesterol (HDL-C, LDL-C), apolipoprotein A-I (apo A-I), and apo B were examined in 26 healthy volunteers who had monthly blood samplings during one calendar year. The estimated CVs for vitamin E were: interindividual, 19.9%, and intraindividual, 11.9%; the index of individuality (I-index) was 0.59. The I-indices for all lipid variables were < 0.51. Serum concentrations of vitamin E, cholesterol, triglycerides, HDL-C, LDL-C, and apo B were lower in spring than in the other seasons. The peak-trough differences in the yearly variations, expressed as a percentage of the mean, were for vitamin E 14.5%, cholesterol 16.2%, triglycerides 14.5%, and LDL-C 24.3%. A significant common annual rhythm was expressed in vitamin E or lipid variables and in the changes in ambient temperature the weeks before blood sampling (inverse relations). There were highly significant positive time relations between serum vitamin E and cholesterol, triglycerides, and apo B. Subjects with higher homeostatic setpoints of cholesterol showed higher homeostatic setpoints of vitamin E, triglycerides, LDL-C, and apo B.

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Reference intervals for plasma apolipoprotein A-1 determined with a standardized commercial immunoturbidimetric assay: results from the Framingham Offspring Study

Clinical Chemistry ◽

10.1093/clinchem/42.4.507 ◽

1996 ◽

Vol 42 (4) ◽

pp. 507-514 ◽

Cited By ~ 92

Author(s):

J Contois ◽

J R McNamara ◽

C Lammi-Keefe ◽

P W Wilson ◽

T Massov ◽

...

Keyword(s):

Coronary Heart Disease ◽

White Men ◽

Reference Intervals ◽

High Density Lipoproteins ◽

Major Protein ◽

Reference Ranges ◽

Men And Women ◽

Apolipoprotein A ◽

The Mean ◽

Plasma Apolipoprotein

Abstract We have evaluated a commercially available, standardized immunoturbidimetric assay of apolipoprotein (apo) A-I, the major protein constituent of high-density lipoproteins (HDL). We determined the reference ranges of plasma apo A-I concentration for white men and women and related these values to the risk of coronary heart disease (CHD). The mean between-run CV for this assay was 2.9%. As determined with individuals participating cycle 4 of the Framingham Offspring Study, the mean (+/- SD) apo A-I concentration was 13% lower in 1879 men (1.34 +/- 0.23 g/L) than in 1939 women (1.54 +/- 0.28 g/L) (P<0.001). An apo A-I concentration of 1.20 g/L roughly corresponded to the 25th percentile value in men and the 5th percentile in women, and subjects with a concentration below this value were significantly more likely to have CHD than subjects wit a higher concentration (P<0.001).

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Effect of Phenobarbitone on Plasma Apolipoprotein B and Plasma High-Density-Lipoprotein Cholesterol in Normal Subjects

Clinical Science ◽

10.1042/cs0560501 ◽

1979 ◽

Vol 56 (5) ◽

pp. 501-504 ◽

Cited By ~ 29

Author(s):

P. N. Durrington

Keyword(s):

Apolipoprotein B ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Hdl Cholesterol ◽

Normal Subjects ◽

Cholesterol Concentration ◽

Low Density ◽

Plasma High Density ◽

Normal Men ◽

Plasma Apolipoprotein

1. Further observations from an earlier study in which phenobarbitone in a dose of 180 mg daily was administered to ten normal men and women for 3 weeks are reported. There was a significant increase in plasma high-denity-lipoprotein (HDL) cholesterol concentration and in the concentration of both total plasma and low-density-lipoprotein (LDL) apolipoprotein B. 2. There was no change in the ratios of the cholesterol: apolipoprotein B and triglyceride: apolipoprotein B in LDL. 3. There was no significant change in plasma very-low-density-lipoprotein (VLDL) apolipoprotein B concentration and the proportion of lipid and apolipoprotein B in VLDL remained unchanged. 4. There was no change in the ratio of HDL:LDL cholesterol concentrations.

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ADIPOCYTE FATTY ACID BINDING PROTEIN (A-FABP) AS A NOVEL BIOCHEMICAL MARKER OF DIABETIC RETINOPATHY

International Journal of Advanced Research ◽

10.21474/ijar01/13553 ◽

2021 ◽

Vol 9 (10) ◽

pp. 339-349

Author(s):

Bhumika Upadhyay ◽

◽

Hina Yaseen ◽

Hina Kauser ◽

Chandra Mohan Kumar ◽

...

Keyword(s):

Diabetes Mellitus ◽

Diabetic Retinopathy ◽

Fatty Acid Binding Protein ◽

Biochemical Marker ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Fatty Acid Binding ◽

Increased Risk ◽

The Mean

Introduction: Diabetes mellitus is acomplex metabolic disorder associated with increased risk of microvascular and macrovascular disease characterized by chronic hyperglycaemia resulting from defect in insulin secretion, insulin action, or both. Diabetic retinopathy (DR) causes visual impairment as a result of long term accumulated damaged to the small blood vessels in the retina.Adipocyte fatty acid binding protein(AFABP), been suggested as a third adipokine, in addition to leptin and adiponectin. AFABP might have a role in the proliferation of endothelial cells, as well as in angiogenesis. A-FABP levels were determined in subjects witout diabetes mellitus, with type 2 diabetes mellitus without DR and with DR at admission in order to investigate a possible association of A-FABP to the increased risk of incidence of DR. Material and methods: This study was done on non-diabetic (n=25) and Type 2 diabetes subjectswith(n=25) and without retinopathy (n=25) who visited HAHC hospital. Blood glucose (fasting and post prandial), glycated hemoglobin(HbA1c), urea, creatinine, uric acid, total protein, serum albumin,serum electrolytes (sodium, potassiumand chloride), totalcholesterol,triglyceride, high density lipoprotein(HDL), low density lipoprotein (LDL), very low density lipoprotein (VLDL) and and AFABP were measured . Result: The mean values of blood glucose (fasting and post prandial),HbA1C,urea, creatinine , TG, LDL VLDL and AFABP were higher in diabetic subjectswith diabetic retinopathy in comparison to diabetic subjects without retinopathy and subjects without diabetes mellitus and were highly significant statistically.(p<0.01). The mean value of HDL was lower in diabetic subjects with diabetic retinopathy in comparison to diabetic subjects without retinopathy and subjects without diabetes mellitus and was highly significant statistically. Conclusion:The study helps in associating AFABP as an early biochemical marker for identifying onset of diabetic retinopathy in subjects with diabetes mellitus at an early stage.

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Clinical significance of lipoprotein size and risk for coronary atherosclerosis

Clinical Chemistry ◽

10.1093/clinchem/41.1.147 ◽

1995 ◽

Vol 41 (1) ◽

pp. 147-152 ◽

Cited By ~ 33

Author(s):

P S Roheim ◽

B F Asztalos

Keyword(s):

Coronary Heart Disease ◽

Heart Disease ◽

Low Density Lipoprotein ◽

Lipoprotein Metabolism ◽

Density Lipoprotein ◽

Apo B ◽

Ldl Particles ◽

Increased Risk ◽

Lipoprotein Size

Abstract Correlation between coronary heart disease and lipoprotein size and composition is well documented. Within the low-density lipoprotein (LDL) family the small LDL particles are associated with increased risk of coronary heart disease. These particles also have increased apolipoprotein (apo) B content. The appearance of these small LDL particles is the manifestation of complex alteration of plasma lipoprotein metabolism. The LDL size is influenced by genetic, endocrine, and environmental factors. Within the high-density lipoprotein (HDL) family the decrease of larger HDL2 particles is associated with coronary heart disease. HDLs can also be separated according to their apoprotein composition into particles containing lipoprotein (Lp)A-I only and particles containing LpA-I and LpA-II. Most studies have shown that the concentration of LpA-I-only particles decreases in coronary heart disease. HDLs are remodeled in the circulation and this remodeling continues in vitro after the blood is taken. Therefore adequate preservation of blood samples is necessary.

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Effect of thyroid function on concentrations of lipoprotein(a)

Clinical Chemistry ◽

10.1093/clinchem/39.12.2466 ◽

1993 ◽

Vol 39 (12) ◽

pp. 2466-2469 ◽

Cited By ~ 46

Author(s):

H Engler ◽

W F Riesen

Keyword(s):

Thyroid Hormones ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Low Density Lipoprotein Cholesterol ◽

Apo B ◽

Thyroid State ◽

Lipoprotein A ◽

The Mean ◽

L 14 ◽

Rule Out

Abstract The effect of thyroid hormones on concentrations of lipoprotein(a) [Lp(a)] was analyzed in 60 patients with active thyroid dysfunction (hyperthyroidism 30 cases, hypothyroidism 32 cases, and 2 cases with opposite changes) and after normalization of the thyroid state. Treatment of hyperthyroidism increased the mean Lp(a) concentrations by 60% (from 73 to 102 mg/L, P < 0.002); at the same time, low-density lipoprotein cholesterol (LDL-C) increased by 53% (from 2.6 to 3.7 mmol/L, P < 0.0001) and apolipoprotein B (apo B) by 35% (from 0.91 to 1.17 g/L, P < 0.0005). In hypothyroidism, the opposite changes were observed: mean Lp(a) decreased from 136 to 114 mg/L (10%, P < 0.02), LDL-C from 4.6 to 3.9 mmol/L (13%, P < 0.01), and apo B from 1.51 to 1.20 g/L (14%, P < 0.01). Although the changes in Lp(a) concentrations did correlate with changes of LDL-C during treatment of hyperthyroidism (r = 0.43, P < 0.05), and with changes in apo B during thyroxine-substitution therapy for hypothyroidism (r = 0.46, P < 0.05), we observed no associations between Lp(a) and LDL-C or apo B in the euthyroid state. These data cannot rule out the possibility that the thyroid hormone-induced increase in LDL-C receptor activity was responsible for the decreased concentrations of Lp(a) in hyperthyroidism. Given that LDL-C is approximately 30% of the Lp(a) molecule but the changes in Lp(a) concentrations are comparable with those in LDL-C (60% vs 53%), and given that Lp(a) is metabolized by an LDL-C-receptor-independent pathway, the present data suggest a direct effect of thyroid hormones on Lp(a) synthesis.

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Quantification of lipoprotein(a) in plasma by assaying cholesterol in lectin-bound plasma fraction

Clinical Chemistry ◽

10.1093/clinchem/40.3.400 ◽

1994 ◽

Vol 40 (3) ◽

pp. 400-403 ◽

Cited By ~ 48

Author(s):

L J Seman ◽

J L Jenner ◽

J R McNamara ◽

E J Schaefer

Keyword(s):

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Cholesterol Content ◽

Lipoprotein A ◽

Apolipoprotein A ◽

Plasma Fraction ◽

Chd Risk ◽

Increased Risk ◽

The Mean ◽

High Concentrations

Abstract Lipoprotein(a) [Lp(a)] is a low-density lipoprotein (LDL)-like particle in which apolipoprotein(a) [apo(a)] is disulfide-linked to apolipoprotein B (apoB). High concentrations of Lp(a) in plasma are associated with an increased risk of coronary heart disease (CHD). Lp(a) has traditionally been measured by immunoassay and expressed as total mass of Lp(a). Measuring Lp(a) by its cholesterol content will provide a way to directly compare Lp(a) with other lipoproteins that are measured by cholesterol. We have developed an assay to quantify Lp(a) by its cholesterol content [Lp(a)-C], using lectin affinity to isolate Lp(a) from other lipoproteins, and then measuring the cholesterol within the isolated fraction. We compared the Lp(a)-C assay with an ELISA for Lp(a) mass in 47 plasma samples from normotriglyceridemic, fasting individuals with high Lp(a) contents (mean +/- SD, 446 +/- 350 mg/L). The mean Lp(a)-C concentration was 110 +/- 89 mg/L and correlated very highly with Lp(a) mass (r = 0.9975). Lp(a)-C measurement is an alternative method to screen for this CHD risk factor.

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Platelet Aggregation and Plasma Lipoproteins in Alcoholics During Alcohol Withdrawal

Thrombosis and Haemostasis ◽

10.1055/s-0038-1661516 ◽

1986 ◽

Vol 55 (02) ◽

pp. 173-177 ◽

Cited By ~ 18

Author(s):

K Desai ◽

J S Owen ◽

D T Wilson ◽

R A Hutton

Keyword(s):

Platelet Aggregation ◽

Alcohol Withdrawal ◽

Ldl Cholesterol ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Hdl Cholesterol ◽

Plasma Lipoprotein ◽

Cholesterol Concentration ◽

Arachidonic Acid Content ◽

Low Density

SummaryPlatelet aggregation, platelet lipid composition and plasma lipoprotein concentrations were measured each week in a group of seventeen alcoholics, without overt liver disease, for one month, following acute, total alcohol withdrawal. The platelets were initially hypoaggregable but, within 1-2 weeks of cessation of drinking, they became hyperaggregable and then gradually returned towards normal values. Hyperaggregability could not be explained by increases in either the cholesterol or the arachidonic acid content of the platelets. Plasma very-low-density lipoprotein cholesterol levels remained high throughout the study, but the initially raised levels of high-density lipoprotein (HDL) cholesterol fell by 26%. Low-density lipoprotein (LDL) cholesterol concentration rose by 10% after two weeks of withdrawal but then returned to about the starting level. The resulting changes in the plasma LDL-cholesterol: HDL-cholesterol ratio, which had increased by more than 50% after two weeks of abstinence, essentially paralleled the time course of enhanced platelet reactivity in all but four of the alcoholics. These findings suggest that alterations in plasma lipoprotein concentrations during acute alcohol withdrawal may be a contributory factor to the haemostatic disorders present in such patients.

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A multicenter prospective hospital-based cohort study on the efficacy and safety of pitavastatin.

Current Diabetes Reviews ◽

10.2174/1573399817666201228164243 ◽

2020 ◽

Vol 17 ◽

Author(s):

Abdullah Shehab ◽

Asim Ahmed Elnour ◽

Akshaya Srikanth Bhagavathula ◽

Joseph Pulavelil Kurian ◽

Gazi Hassan ◽

...

Keyword(s):

Cohort Study ◽

Adverse Events ◽

United Arab Emirates ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Low Density ◽

Efficacy And Safety ◽

Onset Diabetes ◽

The Mean ◽

New Onset

Aims: We aim to investigate the efficacy and safety of pitavastatin 4 mg in a population of people living in the United Arab Emirates (UAE). Background: Pitavastatin is a member of the HMG-CoA reductase inhibitors family which was approved for use in adult subjects with primary hyperlipidemia or mixed dyslipidemia. To date, no published studies have assessed the efficacy and safety of pitavastatin in the United Arab Emirates. Objective: The main objective of the current study was to investigate the efficacy and safety of pitavastatin in subjects with dyslipidemia for primary prevention of cardiovascular diseases based on total cardiovascular risk. Methods: This was a multicentre (four private hospitals) prospective cohort study to analyze data on the use of pitavastatin for dyslipidemia in adult outpatients in Abu Dhabi and Dubai emirates, United Arab Emirates. We have followed-up the clinical profiles of subjects in four hospitals for six-weeks during the period from June 2015 to June 2017. Efficacy was based on the evaluation of the mean (± standard deviation) change in low-density lipoprotein cholesterol between baseline and week six after the initiation of pitavastatin therapy. Safety was reported as the incidence of adverse events occurred with the use of pitavastatin and the development of new-onset diabetes. Results: A total of 400 subjects who were receiving pitavastatin 4 mg were included. The mean age of subjects was 50.7 ±10.8 years, of these 79.0% were males. At the baseline, the mean level of total cholesterol was 185.4 ±41.5 mg/dL, low density lipoprotein was 154.9 ±48.55 mg/dL, high-density lipoprotein cholesterol was 40.5 ±11.23 mg/dL and fasting blood glucose was 115.0 (±16.63) mg/dl. At the end of six weeks, low density lipoprotein levels significantly decreased to 112.09 ±41.90 mg/dl (standard mean difference [SMD] (-42.8%), 95% CI: -42.88 [-49.17 to -36.58] mg/dl, P <0.001), while high density lipoprotein levels improved (SMD, 95% CI: 1.77% [0.25 to 3.28] mg/dl, P <0.022). There were 55 subjects (13.7%) reported various adverse events such as myalgia (7.5%), sleep disorders (2.5%), and myopathy (2.2%). Furthermore, 4 (1.0%) have had developed new-onset diabetes post six-weeks of initiation of pitavastatin therapy. Conclusion: Pitavastatin 4 mg had howed robust efficacy in reducing LDL-C levels and improving HDL-C levels in subjects with dyslipidemias. The use of pitavastatin was associated with a low discontinuation rate, fewer adverse events, and very limited cases of new-onset diabetes.

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Development of Fatty Acid Reference Ranges and Relationship with Lipid Biomarkers in Middle-Aged Healthy Singaporean Men and Women

Nutrients ◽

10.3390/nu13020435 ◽

2021 ◽

Vol 13 (2) ◽

pp. 435

Author(s):

Cody A. C. Lust ◽

Xinyan Bi ◽

Christiani Jeyakumar Henry ◽

David W. L. Ma

Keyword(s):

Disease Risk ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Multiple Regression Model ◽

Dietary Fatty Acids ◽

Lipid Biomarkers ◽

Reference Ranges ◽

Middle Aged ◽

Serum Samples ◽

Biologically Relevant

Dietary fatty acids (FA) are essential for overall human health, yet individual FA reference ranges have yet to be established. Developing individual FA reference ranges can provide context to reported concentrations and whether an individual displays deficient, or excess amounts of FA. Reference ranges of sixty-seven individual FA (μmol/L) were profiled and analyzed using gas chromatography with a flame ionization detector from serum samples collected from 476 middle-aged Singaporean males (BMI:23.3 ± 2.9) and females (BMI:21.8 ± 3.6). Measures of triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol (TC) (mmol/L) were also collected. The mean FA concentration seen in this cohort (11,458 ± 2478 was similar to that of overweight North American cohorts assessed in past studies. Ten biologically relevant FA were compared between sexes, with females exhibiting significantly higher concentrations in four FA (p < 0.05). A multiple regression model revealed the ten FA contributed significantly to nearly all lipid biomarkers (p < 0.05). A majority of participants who had FA concentrations in the ≥95th percentile also exhibited TG, HDL, LDL, and TC levels in the “high” risk classification of developing cardiovascular disease. Future studies profiling individual FA reference ranges in many unique, global cohorts are necessary to develop cut-off values of individual FA concentrations highly related to disease-risk.

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