Effects of niacin on apo A1 and B levels: a systematic review and meta-analysis of randomised controlled trials.

Niacin has been investigated for its potential impact on lipid metabolism and cardiovascular health. This meta-analysis aims to systematically evaluate the effects of niacin interventions on apo A1 and apo B levels, key regulators of lipoprotein metabolism and markers of cardiovascular risk. A comprehensive search of the literature was performed on five databases of PubMed, Scopus, Web of Science, Embase and Cochrane library, from inception up to 15 July 2023. This search identified 1452 publications, from which twelve randomised controlled trials met the inclusion criteria. The intervention dosages ranged from 500 to 3000 mg/d, and the study durations spanned from 6 to 102·8 weeks. The niacin intervention demonstrated a significant reduction in apo B levels (weighted mean differences (WMD): -24·37 mg/dl, P = 0·01). Subgroup analyses indicated that intervention duration played a role, with trials of ≤ 16 weeks showing a greater reduction in apo B. Regarding apo A1, niacin significantly increased its levels (WMD: 8·23 mg/dl, P < 0·001). Subgroup analyses revealed that the beneficial effects of niacin on apo A1 were observed at a dosage of > 1500 mg/d (P < 0·001), and extended-release niacin was more effective compared with other forms (P < 0·001). According to the Begg's regression test, no publication bias was observed in this systematic review and meta-analysis. This meta-analysis highlights niacin's potential role in improving lipid profiles and cardiovascular health. Further well-designed clinical trials are needed to elucidate and confirm optimal dosages and durations of niacin interventions for influencing apo A1 and B.

Comparison of the impact of saturated fat from full-fat yogurt or low-fat yogurt and butter on cardiometabolic factors: a randomized cross-over trial.

PURPOSE: Dairy foods are often a major contributor to dietary saturated fatty acids (SFA) intake. However, different SFA-rich foods may not have the same effects on cardiovascular risk factors. We compared full-fat yogurt with low-fat yogurt and butter for their effects on cardiometabolic risk factors in healthy individuals. METHODS: Randomized, two-period crossover trial conducted from October 2022 to April 2023 among 30 healthy men and women (15 to receive full-fat yogurt first, and 15 to receive low-fat yogurt and butter first). Participants consumed a diet with 1.5-2 servings of full-fat (4%) yogurt or low-fat (< 1.5) yogurt and 10-15 g of butter per day for 4 weeks, with 4 weeks wash-out when they consumed 1.5-2 servings of low-fat milk. At baseline, and the end of each 4 weeks, fasting blood samples were drawn and plasma lipids, glycemic and inflammatory markers as well as expression of some genes in the blood buffy coats fraction were determined. RESULTS: All 30 participants completed the two periods of the study. Apolipoprotein B was higher for the low-fat yogurt and butter [changes from baseline, + 10.06 (95%CI 4.64 to 15.47)] compared with the full-fat yogurt [-4.27 (95%CI, -11.78 to 3.23)] and the difference between two treatment periods was statistically significant (p = 0.004). Non-high-density lipoprotein increased for the low-fat yogurt and butter [change, + 5.06 (95%CI (-1.56 to 11.69) compared with the full-fat yogurt [change, - 4.90 (95%CI, -11.61 to 1.81), with no significant difference between two periods (p = 0.056). There were no between-period differences in other plasma lipid, insulin, and inflammatory biomarkers or leukocyte gene expression of ATP-binding cassette transporter 1 and CD36. CONCLUSION: This study suggests that short-term intake of SFAs from full-fat yogurt compared to intake from butter and low-fat yogurt has fewer adverse effects on plasma lipid profile. CLINICALTRIALS: GOV: NCT05589350, 10/15/2022.

Impact of Physiological Characteristics on Chylomicron Pathway-Mediated Absorption of Nanocrystals in the Pediatric Population.

Nanocrystals exhibit significant advantages in improving the oral bioavailability of poorly soluble drugs. However, the complicated absorption properties of nanocrystals and the differences in physiological characteristics between children and adults limit pediatric applications of nanocrystals. To elucidate the absorption differences and the underlying mechanisms between children and adults, the pharmacokinetics and tissue distribution of aprepitant crystals with different particle sizes (NC200, NC500, and MC2.5) in rats and mice at different ages were studied, and their absorption mechanisms were investigated in Caco-2 cells, mice, and rats. It was found that childhood animals demonstrated higher bioavailability compared with adolescent and adult animals, which was related to higher bile salt concentration and accelerated drug dissolution in the intestine of childhood animals. The majority of nanocrystals were dissolved and formed micelles under the influence of bile salts. Compared with intact nanocrystals, the bile salt micelle-associated aprepitant was absorbed through the chylomicron pathway, wherein Apo B assisted in the reassembling of the aprepitant micelles after endocytosis. Higher bile salt concentration and Apo B expression in the intestines of childhood animals are both responsible for the higher chylomicron transport pathways. Elucidation of the chylomicron pathway in the varied absorption of nanocrystals among children, adolescents, and adults provides strong theoretical guidance for promoting the rational and safe use of nanocrystals in pediatric populations.

A retrospective study of Parkinson's disease in Southwest China 2021-2024: An age-based approach.

BACKGROUND: Globally, Parkinson's disease (PD) is one of the common neurodegenerative diseases in the elderly with increasing morbidity and disability, and its clinical pathogenesis is not clear. OBJECTIVE: To compare the differences in disease severity and blood biomarkers levels and their correlation between patients with early-onset Parkinson's disease (EOPD) and late-onset Parkinson's disease (LOPD). METHODS: A total of 342 patients diagnosed with PD were retrospectively collected. PD patients were categorized into EOPD (24 patients) and LOPD (318 patients) according to the age of onset of the disease. The Hoehn-Yahr (HY) staging was used to assess the severity of the disease in PD patients. Subjective rating scales such as the Mini-mental State Examination (MMSE) were used to assess the motor and non-motor functions of the patients. The differences of objective blood biomarkers such as triglyceride (TG) between the two groups were investigated. The correlation between them and PD was explored by logistic analysis. RESULTS: Percentage of EOPD group with HY staged as intermediate to late and Scales for Outcomes in Parkinson's Disease-Autonomic (SCOPA-AUT), Movement Disorder Society-Unified Parkinson's disease Rating Scale-III (MDS-UPDRS-III), Montreal Cognitive Assessment (MoCA) score and TG, non-high-density lipoprotein-cholesterol (N-HDL-C), homocysteine (HCY), apolipoprotein B (Apo-B), free triiodothyronine (FT3), free thyroxine (FT4), high-sensitivity C-reactive protein (hs-CRP) levels were lower than those in the LOPD group (P < 0.05); and the proportion of HY staged as early stage, Hamilton Anxiety Scale (HAMA) and Fatigue severity scale (FSS) scores and the levels of vitamin B12 were higher than those in the LOPD group (P < 0.05). The results of Multifactorial Logistic regression analysis showed that N-HDL-C [OR = 1.409, 95 % CI (1.063, 1.868)], Apo-B [OR = 0.797, 95 % CI (0.638, 0.997)], Vitamin B12 [OR = 0.992, 95 % CI (0.987, 0.998)] and hs-CRP [OR = 1.124, 95 % CI (1.070, 1.182)] were independent factors affecting the severity of PD, with significant differences between groups (P < 0.05). CONCLUSION: N-HDL-C, Apo-B, Vitamin B12, and hs-CRP levels play an important role in the progression of PD.

A New Case of Abetalipoproteinemia Caused by Novel Compound Heterozygote Mutations in the MTTP Gene without Fat or Vitamin Malabsorption.

Abetalipoproteinemia (ABL) is a rare disease characterized by extremely low apolipoprotein B (apoB)-containing lipoprotein levels, dietary fat, and fat-soluble vitamin malabsorption, leading to gastrointestinal, neuromuscular, and ophthalmological symptoms. We herein report a case of ABL with novel compound heterozygous mutations in the microsomal triglyceride transfer protein gene (c.1686_1687del [p.Ser563TyrfsTer10] and c.1862T>C [p.Ile621Thr]), identified via panel sequencing. Although the patient had extremely reduced low-density lipoprotein cholesterol levels and a fatty liver, he did not exhibit other typical complications. Furthermore, unlike typical ABL, this patient had a preserved apoB-48 secretion and increased concentrations of high-density lipoprotein cholesterol, which may account for the normal serum fat-soluble vitamin levels.

Association Apo B/Apo a-1 Ratio and Prognostic Nutritional Index with 90-Day Outcomes of Acute Ischemic Stroke.

Background: The relationship between insulin resistance-related indices and the outcomes of acute ischemic stroke (AIS) is still unclear. This study aimed to explore the association between the Apo B/Apo A-1 ratio and the Prognostic Nutritional Index (PNI) with the 90-day outcomes of AIS. Methods: A total of 2011 AIS patients with a 3-month follow-up were enrolled in the present study from January 2017 to July 2021. Multivariate logistic regression modeling was performed to analyze the relationship between Apo B/Apo A-1 ratio, PNI, and AIS poor outcomes. The mediating effect between the three was analyzed using the Bootstrap method with PNI as the mediating variable. Results: Among the 2011 included AIS patients, 20.3% had a poor outcome. Patients were categorized according to quartiles of Apo B/Apo A-1 ratio and PNI. Multivariate logistic regression revealed that the fourth Apo B/Apo A-1 ratio quartile had poorer outcomes than the first quartile (OR 1.75,95%CL 1.21-2.53, P=0.003), and the fourth PNI quartile exhibited a lower risk of poor outcomes than the first quartile (OR 0.40, 95%CL 0.27-0.61, P<0.001). PNI displayed a significant partially mediating effect (21.4%) between the Apo B/Apo A-1 ratio and poor AIS outcomes. Conclusion: The Apo B/Apo A-1 ratio is a risk factor for poor AIS outcomes, whereas PNI acts as a protective factor. The association between the ApoB/ApoA-1 ratio and poor AIS outcomes was partially mediated by PNI.

The Impact of Metabolic and Bariatric Surgery on Apo B100 Levels in Individuals with high BMI: A Multi-Centric Prospective Cohort Study.

BACKGROUND: Metabolic and Bariatric surgery (MBS) leads to significant weight loss and improvements in obesity-related comorbidities. However, the impact of MBS on Apolipoprotein B100 (Apo-B100) regulation is unclear. Apo-B100 is essential for the assembly and secretion of serum lipoprotein particles. Elevated levels of these factors can accelerate the development of atherosclerotic plaques in blood vessels. This study aimed to evaluate changes in Apo-B100 levels following MBS. METHODS: 121 participants from the Iranian National Obesity and Metabolic Surgery Database (INOSD) underwent Laparoscopic Sleeve Gastrectomy (LSG) (n = 43), One-Anastomosis Gastric Bypass (OAGB) (n = 70) or Roux-en-Y Gastric Bypass (RYGB) (n = 8). Serum Apo-B100, lipid profiles, liver enzymes, and fasting glucose were measured preoperatively and six months postoperatively. RESULTS: Apo-B100 levels significantly decreased from 94.63 ± 14.35 mg/dL preoperatively to 62.97 ± 19.97 mg/dL after six months (p < 0.01), alongside reductions in total cholesterol, triglycerides, LDL, VLDL, AST, and ALT (p < 0.05). Greater Apo-B100 reductions occurred in non-diabetics versus people with diabetes (p = 0.012) and strongly correlated with baseline Apo-B100 (r = 0.455, p < 0.01) and LDL levels (r = 0.413, p < 0.01). However, surgery type did not impact Apo-B100 changes in multivariate analysis (p > 0.05). CONCLUSION: Bariatric surgery leads to a significant reduction in Apo-B100 levels and improvements in lipid profiles and liver enzymes, indicating a positive impact on dyslipidemia and cardiovascular risk in individuals with high BMI.

Effects of vitamin C supplementation on oxidative stress and serum paraoxonase/arylesterase activities in patients on long-term hemodialysis / Efectos de la suplementación con vitamina C sobre el estrés oxidativo y las actividades de paraoxonasa/arilesterasa sérica en pacientes en hemodiálisis a largo plazo

Background: Oxidative stress increases oxidizability of apolipoprotein-B containing lipoproteins and decreases paraoxonase (PON) activity in hemodialysis (HD) patients and plays an important part in the development of atherosclerotic cardiovascular diseases. In HD patients, plasma ascorbic acid (AA) levels are decreased either due to the loss by hemodialysis membranes or due to malnutrition and contribute to the imbalance of antioxidant defense mechanisms. We hypothesized that long-term ascorbic acid (AA) supplementation recovers oxidizability of lipoproteins in HD patients by reinforcing PON activity. Methods: Twenty-nine adult patients were treated with 100mg and 500mg AA at the end of each HD session thrice a week for two consecutive 16 weeks-periods, respectively. Blood samples were obtained before the first HD session and prior to the first HD sessions following the 100mg AA-supplemented and the 500mg AA-supplemented periods. Results: PON activities were significantly increased after 100mg (p<0.05) and 500mg AA (p<0.001) supplementation periods compared to the basal level. Apo-B lipoprotein oxidizability (Δ-MDA) was significantly decreased after 500mg AA supplementation compared to both basal (p<0.05) and 100mg AA supplementation periods (p<0.05). Plasma AA concentrations were negatively correlated with Δ-MDA levels (R=−0.327; p<0.01). Conclusion: Our results suggest that long-term parenteral 500mg AA supplementation improves PON activity alleviating apo B-containing lipoproteins oxidizability in HD patients. (AU)

Antecedentes: El estrés oxidativo aumenta la susceptibilidad a la oxidación de las apolipoproteínas-B que contienen lipoproteínas y reduce la actividad de paraoxonasa (PON) en pacientes de hemodiálisis (HD) formando un papel importante en el desarrollo de enfermedades arterioescleróticas cardiovasculares. En pacientes de HD, los niveles de ácido ascórbico (AA) plasmático disminuyen debido a la pérdida por membranas de hemodiálisis o por desnutrición, y contribuye al desequilibrio de los mecanismos de defensa antioxidantes. Nuestra hipótesis es que a largo plazo la suplementación con AA recupera la susceptibilidad a la oxidación de las lipoproteínas en pacientes de HD al reforzar la actividad de PON. Métodos: Se trataron 29 pacientes adultos con 100 y 500mg de AA al final de cada sesión de HD/3 veces por semana/durante 2 períodos consecutivos de 16 semanas, respectivamente. Se obtuvieron muestras de sangre antes de la primera sesión de HD y previo a las primeras sesiones de HD luego de los 100mg suplementados con AA y los periodos suplementados con 500mg de AA. Resultados: Las actividades de PON aumentaron significativamente después de los periodos de suplementación de 100mg (p<0,05) y de 500mg de AA (p<0,001) comparados con el nivel base. La susceptibilidad a la oxidación de la lipoproteína apoB (Δ-MDA) disminuyó significativamente luego de la suplementación de 500mg de AA en comparación con períodos de valores base (p<0,05) y los de 100mg de AA (p<0,05). La correlación entre las concentraciones de plasma AA y los niveles de Δ-MDA resultó negativa (R=−0,327; p<0,01). Conclusión: Nuestros resultados sugieren que la suplementación parenteral a largo plazo de 500mg de AA mejora la actividad de PON mitigando la susceptibilidad a la oxidación de las lipoproteínas que contienen apoB en pacientes en HD. (AU)

The apolipoprotein B/A-1 ratio in practically healthy participants with normolipidemia / Монголын Анагаах Ухаан

Introduction@#Studies demonstrated that the apolipoprotein B/apolipoprotein A-I (Apo B/apo A-I) ratio predicts cardiovascular risk better than any of the cholesterol indexes. Apo B and Apo A-1 are assumed to be superiormarkers for lipoprotein abnormalities [1,2]. The concentrations of Apo B and Apo A-1 are associated with cardiovascular disease more strongly than the corresponding lipoprotein cholesterol fractions, the discriminant value of these apoproteins in absolute terms appears to be less important than of their ratio (the Apo B/Apo A-1 ratio) [3, 5-7]. The Apo B/Apo A-1 ratio reflects the balance of atherogenic and antiatherogenic lipoproteins in plasma [4]. Multiple clinical and epidemiological studies have confirmed that the Apo B/Apo A-1 ratio is a superior marker for cardiovascular disease compared with lipids and lipoproteins or their ratios [8, 9].@*Goal@#We determined the variation limits of the Apo B/Apo A-1 ratio in healthy participants with normolipidemia and the relationship of this ratio with other lipid parameters.@*Material and Methods@#A total of 146 normolipidemic healthy participants aged 25–60 years were included in the study. Anthropometric measurements (height and weight) and other personal information were obtained during the clinical examination and the interview. Participants were included in the study using the following criteria: </br>1. body mass index < 30 kg/m2; </br> </br>2. TC < 5.2mmol/L; </br>3. triglycerides (TG) ≤1.7 mmol/L; </br>4. HDL-C ≥1.03 mmol/L ( woman), ≥ 1.29 mmol/L (male) . </br>The plasma levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), apo A-I, Apo B and Apo B/Apo A-1 were determined after a 12 h fasting period. The non-HDL-C was calculated as the difference between the TC and HDL-C. Most research data emphasized that the values for the Apo B/Apo A-1 ratio that define a high cardiovascular risk were proposed to be 0.9 for men and 0.8 for women. Statistical Analysis. The statistical analysis was performed using SPSS 21.0 (USA). Differences between the groups were analyzed using the Mann-Whitney test and the chi-squared test. Correlations between the indices were assessed using the Spearman’s rank correlation. A value of < 0.05 was accepted as statistically significant.@*Results@#The relationship of ratio of apolipoprotein (Apo) B/Apo A-1 with other indicators of lipid metabolism in healthy people with normal lipidemia was analyzed. The Apo B/Apo A-1 ratio in the studied normolipidemic subjects was 0.69 ± 0.17. The percentage of subjects with the Apo B/Apo A-1 ratio exceeding 0.9 (the accepted risk value of cardiovascular disease) was 36.3 %.The subjects with Apo B/Apo A-1>0.9 were characterized by higher HDL-C levels and atherogenic Aпo B, Apo B/Apo A-1 but lower values Apo A-1.@*Conclusion@#The subjects with normolipidemia the unfavorable Apo B/Apo A-I ratio> 0.9 had more atherogenic lipid profile.

Correlation of Apo-A and Apo-B/Apo-A ratio with the degree of coronary artery stenosis in patients with coronary heart disease / 西安交通大学学报(医学版)

Objective: To investigate the correlation of Apo-A and Apo-B/Apo-A ratio with the degree of coronary artery stenosis (CHD) in patients with coronary heart disease. Methods: Totally 234 patients with coronary heart disease examined with coronary angiography were collected. We collected blood lipid and calculated blood lipid ratio, such as non-HDL-C, TG/HDL-C, TC/HDL-C, LDL-C/HDL-C, and Apo-B/Apo-A. Gensini score was calculated according to the result of CAG. We analyzed the correlation between the blood lipid indicators and the Gensini score with the Spearman correlation analysis. Linear regression analysis was made of the correlation between those meaningful indicators and the Gensini score. Results: There were no significant differences in age, hypertension, diabetes or smoking index between all Gensini score groups. The illness course in middle-score group was longer than that in low-score group and high-score group (P=0.023, P=0.002). There was a significant difference in Apo-A between the groups (P=0.009, P<0.001, P=0.013). The levels of TC, Apo-B and LPα in high-score group were lower than those in low-score group (P=0.008, P=0.001, P=0.002). The levels of HDL-C and Apo-B/Apo-A ratio in both middle-score and high-score group were lower than those in low-score group (P=0.008, P=0.001). The Spearman correlation analysis between various risk factors and Gensini score found that HDL-C and Apo-A had negative correlation with Gensini score (r=-0.166, r=-0.294), the ratios of LDL-C/HDL-C and Apo-B/Apo-A were positively correlated with Gensini score (r=0.159, r=0.170). By multi-factor linear regression, Apo-A was negatively related with Gensini score (β=-62.249), and Apo-B/Apo-A ratio was positively associated with Gensini score (β =31.311). Conclusion: Apo-A and Apo-B/Apo-A ratios are the independent risk factors for the stenosis degree of coronary artery in patients with CHD. They are reliable predictors for the risk of CHD.

Insulin resistance and apolipoprotein B as a metabolic syndrome risk factor in normal glucose tolerance / 대한내과학회지

BACKGROUND: Insulin resistance is associated with greatly increased risk of coronary artery disease. Serum apolipoprotein B and the ratio of apo A-1/Apo B are important markers of the coronary artery disease. The aim of this study was to assess the association of serum apolipoprotein B and the ratio of apo A-1/Apo B with insulin resistance in normal glucose tolerance. METHODS: From individual, who participated in medical screening at health promotion center in Kangbuk Samsung Hospital from Jan. to Dec. 2002, total 7427 participants (4356 men, 3071 women) were enrolled in this study. All participants was no personal history of diabetes and normal fasting glucose. We assess the clinical characteristics and biochemical parameters of subjects. RESULTS: Apolipoprotein B, total cholesterol/HDL-C and LDL-C/HDL-C show an positive correlation with metabolic syndrome and insulin resistance (p<0.001). Apo A-I, Apo A-I/Apo B, LDL/Apo B and HDL/Apo A-I show an negative correlation with metabolic syndrome and insulin resistance (p<0.001). CONCLUSION: These data suggest that insulin resistance are associated with serum apolipoprotein B and the ratio of apo A-1/Apo B in normal glucose tolerance. And early diagnosis and tight control of insulin resistance in normal glucose tolerance should be administered for the prevention of coronary artery disease.

A Simplified Colorimetric Assay of Nonenzymatic Glycosylation of Human low Density Lipoproteins in Normal and Diabetes Mellitus

A simplified colorimetric method for measurement of the levels of glycosylation of proteins was developed by a modification of an existing method. Employing this method, the extent of nonenzymatic glycosylation of apolipoprotein B subspecies(B-100, B-74, B-26), LDL, VLDL and total serum proteins in human plasma obtained from patients with diabetes mellitus and control subjects was compared. Plasma LDL (1.019 < d < 1.063) and VLDL(d < 1.006) were separated using the sequential ultracentrifugation method, and the subspecies of apolipoprotein B were isolated by extracting them from polyacrylamide gels after they were separated by preparative SDS-polyacrylamide gel electrophoresis. Increases in the level of glycosylation of serum proteins, LDL, VLDL, and apo B subspecies obtained from diabetic patients were observed. Among them, the increases of glycosylated LDL and apo B-26 were most significant (p < .001). Also, good correlations were found between glycosylations of apo B-26 and LDL (r=.88), and glycosylation of LDL and LDL cholesterol level(r=.79). The results also showed an excellent correlation between levels of HbA1c and glycosylated apo B-26(r=.93).

Efeitos da pravastatina nas lipoproteínas, Lp(a), apo B e apo A-I em pacientes com hipercolesterolemia primária / Effects of Pravastatin on Lipoproteins, Lp(a), apo B and apo A-I in Patients with Primary Hypercholesterolemia

PURPOSE--To evaluate the effects of pravastatin on lipoproteins, Lp (a), apo B and apo A-I and its tolerability in primary hypercholesterolemic patients in our outpatient lipid clinic. METHODS--Twenty-two primary hypercholesterolemic patients were evaluated. They had all been treated previously with other hypocholesterolemic drugs, including the statins, forming a specific and homogeneous group with hypercholesterolemia and definite coronary risk. After 7 weeks with American Heart Association phase I diet and placebo drug, pravastatin was administered during 12 weeks. All patients received an initial daily dose of 10 mg for six weeks. After this period, this dose was increased to 20 mg. The levels of cholesterol, triglycerides, high-density lipoprotein, lipoprotein (a) and apolipoproteins A-1 and B were determined. RESULTS--No changes occurred with diet and placebo, but pravastatin at a daily dose of 10 mg, reduced significantly cholesterol level (7.22 per cent) LDL-cholesterol (13.08 per cent) and increased HDL-cholesterol (7.8 per cent). The results were better with 20 mg, achieving a reduction of (28.21 per cent) in cholesterol, (36.88 per cent) in LDL-cholesterol, (17.06 per cent) in apo B level and an increase of (10.06 per cent) in HDL-cholesterol. The smaller effect observed with the more commonly used dosage (10 mg/day) was most probably due to the characteristics of the sample with already established hypercholesterolemia, being thus dependent of higher concentrations of medications, as observed in previous treatments in our outpatient clinic. Side affects with this drug were rare. No biochemical changes were observed that would interrupt the continuation of therapy. CONCLUSION--Pravastatin was well tolerated and promoted favorable changes in the total cholesterol, LDL, apo B and cholesterol/HDL and LDL/HDL ratios of primary hypercholesterolemic patients

Plasma LDL Particle Sizes Affect the Blood Lipid Profile and Dietary Intakes among Korean Adults / 대한지역사회영양학회지

The purpose of this research was to examine the relationship between the plasma LDL particle size and blood lipid profile, dietary factors and anthropometric values (body mass index, waist circumference and waist/hip ratio). The subjects were 173 adults aged 23 to 81 years, selected from the Outpatient Clinic and Cardiovascular Department of the Seoul Municipal Hospital. Dietary data were obtained using a 3-day food record and analyzed using Korean and US nutrient databases. The subjects were divided into three groups by LDL particle size:type A (large buoyant LDL, > 25.5 nm, n = 96), type I (Intermediate LDL, 25.2 < or = - < or = 25.5 nm, n = 18), and type B (small dense LDL, < 25.2 nm, n = 59) groups. The type B group had higher age, waist circumference, and waist/hip ratio (WHR) than the type A and type I groups. Serum concentration of triglyceride, Apo B, LDL/HDL cholesterol ratio and atherogenic index were significantly higher in the type B group as compared to those in the other two groups. HDL cholesterol level and Apo A-I/Apo B ratio were significantly lower in the type B group than the other two groups. The plasma LDL particle size was highly correlated with triglyceride (r = -0.450), Apo B (r = -0.402) and HDL cholesterol (r = 0.418). However, there was no correlation between plasma LDL particle size and dietary intakes. This study showed that small dense LDL was an important biochemical risk factor that was associated with other risk factors.

Quantificação das apoliproteínas A-I e B em soros normo e hipertrigliceridêmicos, conservados em condições de diferentes temperaturas / Measurement of apolipoproteins A-I and B in normal and hypertriglyceridemic serum stored under different conditions

1.) Utilizando método de imunoturbidimetria, nós medimos as concentrações das apolipoproteínas A-I e B, em amostras de soros normo e hipertrigliceridêmicos, estocados por um período de 94 dias. Alíquotas desses soros foram estocadas a 4°C, -20°C ou em nitrogênio líquido (-170°C). Três “pools” de soros foram usados, contendo respectivamente, 148, 491 e 964 mg/dl de triglicérides (TG). 2.) Nossos resultados mostraram que tanto soros normo quanto hipergliceridêmicos podem ser estocados a 4°C por um período de 8 dias, antes da determinação de apo A-I e apo B por imunoturbidimetria. Com o congelamento a -20°C ou no nitrogênio líquido (-170°C) , as determinações apo A-I foram imediatamente alteradas em 14% no “pool” de soros que continha valores altos de triglicérides, enquanto os outros dois “pools” não mostraram alterações significativas. Os valores de apo B aumentaram em todos os “pools” de soros após o congelamento a -20°C, enquanto no nitrogênio líquido houve significante alteração somente no soro com valores médios e altos de TG.

Níveis de LDL-C, HDL-C e de apolipoproteínas B e A-I em indivíduos normo e hiperlipidêmcos e suas correlações com os níveis de triglicérides / Levels of LDL-C, HDL-C and apolipoproteins B and A-I normo and hyperlipidemic indiviuals and their correlations with triglyceride levels

Os níveis plasmáticos de LDL-colesterol (LDL-C), HDL-colesterol (HDL-C), apolipoproteínas B (apo B) e A-I (apo A-I) foram estimados em 38 indivíduos hiperlipidêmicos (HL) e 42 normolipidêmicos (NL). Coeficientes de correlação, entre essas variáveis e os níveis de TG, foram calculados, em cada grupo. O teor de LDL-C, apo B e as razões LDL-C/HDL-C e apo B/apo A-I apresentaram-se significativamente maiores (p>0,001) nos HL do que nos NL. Entretanto, utilizando-se análise discriminante, observamos que a discriminação mais acentuada, nos hl, foi obtida pela razão apo B/apo A-I, que classificou 87% dos pacientes no grupo correto. O teor de HDL-C foi significativamente menor no grupo dos HL do que no de NL (p0,05). No grupo de NL, os resultados da correlação entre os níveis de TG com as outras variáveis fora: a) positiva e significativa com os níveis de LDL-C e apo B; b) negativa e significativa com os níveis de HDL-C; c) não significativa com o nível de apo A-I. No grupo de HL, encontramos correlações negativas entre os níveis de TG com os de LDL-C, HDL-C, não havendo correlação significativa com apo B e apo A-I.