We studied the biological variability and responsiveness to dietary fat of plasma lipoprotein cholesterol and triacylglycerol concentrations. Ten normal persons were studied on 3 consecutive days while they were eating their unrestricted usual diets and after 8, 9, and 10 d of eating a constant high-fat and low-fat diet administered in a crossover design. The changes in plasma low-density-lipoprotein (LDL)-cholesterol concentrations from baseline with the high-fat diet were inversely correlated with the changes from baseline with the low-fat diet (r = -0.74, P = 0.01), as well as with the changes from the low-fat to high-fat diet (r = -0.93, P < 0.001). The extent of increases in plasma LDL-cholesterol concentrations from the baseline to the high-fat diet were positively correlated with the increases from the low-fat to the high-fat diet (r = 0.93, P < 0.001). The responses of high-density-lipoprotein (HDL) cholesterol were not consistently correlated. The within-person between-day CV of LDL decreased from 10% with the unrestricted diet to 6% (P < 0.05) with the high-fat diet and to 7% with the low-fat diet (NS). The CV of total triacylglycerol (22%) and very-low-density-lipoprotein (VLDL) triacylglycerol (48%) on the unrestricted diet significantly decreased by 51-59% during both controlled diets (P = 0.03-0.06). The CV of HDL cholesterol was 5.3% during baseline, 4.2% during the high-fat diet, and 3.2% during the low-fat diet (P = 0.4, 0.19, respectively). In summary, individuals have a reproducible plasma LDL-cholesterol response when changing their dietary fat intake. The day-to-day variation in total triacylglycerol, VLDL triacylglycerol, and LDL-cholesterol concentrations decreases when day-to-day dietary variation is eliminated.

A placebo-controlled crossover study was conducted to evaluate whether lipid-lowering with gemfibrozil (10 to 12 weeks) affects platelet function in vivo at rest and during mental stress in 21 men with combined hyperlipoproteinemia. Gemfibrozil lowered plasma triglycerides and total and VLDL cholesterol (P < .001 for all), whereas HDL cholesterol increased (P < .001). Gemfibrozil increased platelet counts by 18% (P < .001) and, according to filtragometry measurements, enhanced overall (means of rest and stress values) platelet aggregability in vivo (P = .014); this effect was more evident during mental stress (P = .027) than at rest (P = .18). Moreover, the urinary excretion of 11-dehydro-thromboxane-B2 was 54% higher during treatment with gemfibrozil (P < .001), whereas the excretion of beta-thromboglobulin in urine was unaltered. Plasma beta-thromboglobulin tended to be slightly elevated during active treatment (P = .15). Mental stress increased heart rate and catecholamine levels and elevated all cholesterol fractions (P < .01) and plasma beta-thromboglobulin (during placebo, P = .02), but platelet aggregability did not increase significantly. A positive correlation was found between 11-dehydrothromboxane-B2 excretion and LDL cholesterol levels during placebo (r = .62, P = .0057). In conclusion, gemfibrozil has beneficial effects on plasma lipoprotein levels but enhances several aspects of platelet activity in vivo and increases platelet counts. These changes might be prothrombotic and thus adverse for the hyperlipidemic patient. Primary preventive effects of gemfibrozil might be enhanced if a platelet inhibitor such as aspirin is administered with gemfibrozil.

Decreased blood level of high-density lipoprotein (HDL) is one of the essential criteria in diagnosing metabolic syndrome associated with the development of atherosclerosis and coronary heart disease. Herein, we report the synthesis of a molecularly imprinted polymer (MIP) that selectively binds HDL, namely, HDL-MIP, and thus serves as an artificial, biomimetic sensor layer. The optimized polymer contains methacrylic acid and N-vinylpyrrolidone in the ratio of 2:3, cross-linked with ethylene glycol dimethacrylate. On 10 MHz dual electrode quartz crystal microbalances (QCM), such HDL-MIP revealed dynamic detection range toward HDL standards in the clinically relevant ranges of 2-250 mg/dL HDL cholesterol (HDL-C) in 10 mM phosphate-buffered saline (PBS, pH = 7.4) without significant interference: low-density lipoprotein (LDL) yields 5% of the HDL signal, and both very-low-density lipoprotein (VLDL) and human serum albumin (HSA) yield 0%. The sensor reveals recovery rates between 94 and 104% at 95% confidence interval with precision of 2.3-7.7% and shows appreciable correlation (R 2 = 0.97) with enzymatic colorimetric assay, the standard in clinical tests. In contrast to the latter, it achieves rapid results (10 min) during one-step analysis without the need for sample preparation. Graphical Abstract ᅟ.

To evaluate in vivo animal model of cardiac ischemia/reperfusion the cardioprotective activity of pancreatic lipase inhibitor of the orlistat.

Adult male Wistar rats were anesthetized, placed on mechanical ventilation and underwent surgery to induce cardiac I/R by obstructing left descending coronary artery followed by reperfusion to evaluation of ventricular arrhythmias (VA), atrioventricular block (AVB) and lethality (LET) with pancreatic lipase inhibitor orlistat (ORL). At the end of reperfusion, blood samples were collected for determination of triglycerides (TG), very low-density lipoprotein (VLDL), low-density lipoprotein (LDL), high-density lipoprotein (HDL), lactate dehydrogenase (LDH), creatine kinase (CK), and creatine kinase-MB (CK-MB).

Treatment with ORL has been able to decrease the incidence of VA, AVB and LET. Besides that, treatment with ORL reduced serum concentrations of CK and LDL, but did not alter the levels of serum concentration of TG, VLDL and HDL.

The reduction of ventricular arrhythmias, atrioventricular block, and lethality and serum levels of creatine kinase produced by treatment with orlistat in animal model of cardiac isquemia/reperfusion injury suggest that ORL could be used as an efficient cardioprotective therapeutic strategy to attenuate myocardial damage related to acute myocardial infarction.

BACKGROUND

Low blood levels of antioxidants are associated with an increased risk of developing coronary artery disease. Lipophilic antioxidants are transported in lipoproteins, and hypolipidaemic therapy may therefore alter their blood concentrations.

METHODS

The present randomized, placebo-controlled cross-over study of 21 men with combined hyperlipidaemia examines whether 10-12 weeks of gemfibrozil treatment affects the serum concentrations of the antioxidants ubiquinone-10 or alpha- or gamma-tocopherol.

RESULTS

Gemfibrozil treatment lowered plasma triglycerides and both total and very low-density lipoprotein (VLDL)-cholesterol (P < 0.001 for all by ANOVA), whereas high-density lipoprotein (HDL)-cholesterol increased (P < 0.001). The median serum levels of ubiquinone-10 decreased from 1.30 mumol L-1 (interquartile range 0.87-1.71 mumol L-1) with placebo to 0.76 mumol L-1 (0.66-0.95) with gemfibrozil treatment (P < 0.001). Corresponding levels for alpha- and gamma-tocopherol were: 68.5 mumol L-1 (51.1-84.7) vs. 40.8 mumol L-1 (30.3-55.0) and 8.6 mumol L-1 (5.2-16.7) vs. 4.3 mumol L-1 (3.5-7.0) respectively (P < 0.001 for both). The decrease in serum antioxidants was also evident when standardized for total cholesterol (P < 0.05) or LDL-cholesterol (P < 0.001). Normolipaemic control subjects had significantly lower antioxidant levels than placebo-treated patients: ubiquinone 0.63 mumol L-1 (0.41-1.05), alpha-tocopherol 34.3 mumol L-1 (27.3-45.6) and gamma-tocopherol 3.2 mumol L-1 (2.5-4.2) (P < 0.001 for all). The association of antioxidants with lipoprotein lipids was further established by positive correlations between the levels of antioxidants and those of total cholesterol (r = 0.64, P < 0.001) or total triglycerides (r = 0.71, P < 0.001).

CONCLUSIONS

Gemfibrozil treatment of men with combined hyperlipidaemia reduces serum antioxidant levels to the levels seen in healthy normolipidaemic men. The mechanisms and the relevance of this finding remain unclear and need to be addressed in further studies.

We have shown that inclusion of the antioxidant butylated hydroxytoluene (BHT) in the diet protects against development of atherosclerotic lesions in cholesterol-fed rabbits. In parallel, BHT treatment results in increased plasma triglyceride levels. The present study explores the relationship between the triglyceride-inducing and protective effects of BHT in two different studies. The combined material contains 22 rabbits fed cholesterol and 18 rabbits fed cholesterol in combination with 1% BHT. In the BHT group there was an inverse relationship between triglyceride exposure/cholesterol exposure and extent of lesions with r=0.74 (P=0.0005). Our results show that increased triglyceride exposure parallels the anti-atherogenic effect of BHT. There was no significant correlation between atheromatosis and serum BHT levels. beta-very low density lipoprotein (beta-VLDL) from cholesterol and BHT animals was triglyceride-enriched and smaller compared to beta-VLDL from cholesterol-fed animals, but there was no significant association between the anti-atherogenic effect of BHT and particle size or apolipoprotein pattern of LDL or beta-VLDL. LDL isolated from rabbits treated with cholesterol and BHT was less sensitive to oxidative modification than LDL isolated from rabbits treated with cholesterol only. In conclusion, our results demonstrate that the degree of triglyceride exposure may be an important modulator of the anti-atherogenic effect of an antioxidant.

OBJECTIVE

Obesity is a pro-atherogenic condition and postprandial lipoprotein profile and circulating cytokines changes may contribute to promote the process. The aim of this study is to investigate postprandial metabolic response, lipoprotein oxidation and circulating cytokine levels, after the ingestion of two different meals with different fat/carbohydrate ratio.

RESULTS

Ten prepubertal obese boys consumed two meals with the same energy and protein content but with a different carbohydrate to fat ratio: 1) moderate fat (MF): 61% carbohydrate, 27% fat; 2) high fat (HF): 37% carbohydrate, 52% fat. The AUC of glucose and insulin were significantly (p < 0.05) lower after the HF meal. HF meal was followed by a significant decrease in the cholesterol carried in the HDL fractions, while cholesterol in the small, dense LDL and in the VLDL particles increased, as compared to baseline (p < 0.05 for all). No differences were found in the cholesterol distribution after the MF meal. Moreover, HDL-C concentration was lower (p < 0.05) at 300 min after HF vs. MF meal. Oxidized LDL (ox-LDL) concentration increased after the HF meal but not after the MF meal [9.3(2.2) vs 1.8(2.2)% from baseline, P < 0.02)]. A positive association (r>> 0.3, P < 0.05) was observed between the densest LDL particles and the ox-LDL plasma levels. A reduction of IL-6 was found at 120 min after the MF [-23.3(5.5) vs -8.4(3.8)% from baseline, P < 0.05)] compared with the HF meal.

CONCLUSIONS

A simple change of ≈25% of energy load from fat to carbohydrate in a meal significantly improves postprandial pro-atherogenic factors in obese boys.

The effects of chylomicron remnants enriched in n-3 or n-6 polyunsaturated fatty acids (derived from fish or corn oil respectively) on the secretion of very-low-density lipoprotein (VLDL) lipid and apolipoprotein B (apoB) by rat hepatocytes in culture was investigated. Remnants were prepared in vivo from chylomicrons obtained from rats given an oral dose of fish or corn oil and incubated with cultured hepatocytes for up to 16 h. The medium was then removed and the secretion of cholesterol and triacylglycerol into the whole medium or the rho<1.050 g/ml fraction during the following 7-24 h was determined. After exposure of the cells to fish-oil as compared with corn-oil remnants, secretion of both cholesterol and triacylglycerol into the whole medium was decreased by 25-35%, and secretion into the rho<1.050 g/ml fraction was decreased by 20-25%. In addition, the levels of apoB48 found in the rho<1.050 g/ml fraction were significantly lower in cells treated with fish-oil rather than corn-oil remnants, although the levels of apoB100 remained unchanged. The expression of mRNA for apoB, as determined by reverse-transcriptase PCR, however, was not significantly changed after exposure of the cells to both types of remnants. These results demonstrate that the effects of dietary n-3 polyunsaturated fatty acids in depressing hepatic VLDL secretion occur directly when they are delivered to the liver from the intestine in chylomicron remnants, and that the secretion, but not the synthesis, of apoB is targeted.

OBJECTIVE

Measurement of inflammatory markers for risk stratification of vascular disorders has been the focus of numerous investigations worldwide, and usually reveals augmented levels of circulating cytokines/chemokines among carriers of classic risk factors for atherosclerosis. Nonetheless, this low-grade inflammatory milieu detected in aged individuals tends to be influenced by body composition. Moreover, cardiovascular risk factors have a complex genetic etiology, and disregarding the genetic heritage may produce spurious results owing to interethnic differences. In this complex scenario, our study was designed to verify the existence and strength of the association between selected mediators of systemic inflammation and classic risk factors of cardiovascular diseases (CVD).

METHODS

In a sample of post-menopausal older women, correlation analyses explored the association of circulating levels of IL1α, IL1β, IL8, IL10 and IL12 with atherosclerosis-related clinical/metabolic parameters, using age, body mass index (BMI), genetic ancestry estimates as standard correction factors. Further adjustment for use of therapeutic agents was applied when appropriate.

RESULTS

Our analyses revealed association of log10-transformed IL-12 titers with VLDL-c levels (r=.192; p=.002) and with SBP (r-.185; p=.003), and of log10-transformed IL-8 titers with GLY (r=.235; p<.001).

CONCLUSIONS

Interpretation to the results account to a possible dysregulation of the PPAR signaling pathway to explain the association of IL12 and VLDL-c, and to IL8-driven mechanisms to promote dysglycemia. No previous report sought to investigate the relationship between this set of inflammatory markers and classic risk factors for atherosclerosis correcting for the heterogeneity in genetic admixture and body composition of Brazilian post-menopausal women.

BACKGROUND

People are aware of the consequences of high serum lipid levels, specifically, total cholesterol. Awareness about harmful effects of very low levels of serum lipids is still lacking. Very low levels of serum lipids lead to psychological consequences.

OBJECTIVE

The objective of this study was to show whether there was a significant relationship between serum lipid levels and depression.

METHODS

Total 70 subjects were included in this study. 40 subjects suffering from depression as assessed with the help of clinical findings and Beck Depression Inventory (BDI) scores were included in the study group, while control group comprised of 30 normal subjects. Lipid profile was done on blood samples obtained after overnight fasting. BDI scores were also obtained in control group using BDI. Co-relation between BDI score and lipid levels was obtained in both the groups.

RESULTS

Serum lipid levels were significantly low in study group as compared to control group. There was a significant negative co-relationship between serum lipid levels with depression. Subjects of study group having lower lipid levels specifically Total Cholestrol (TC) (r = -0.78), Low-Density Lipoprotein (LDL) (r = -0.69), TG (r = -0.41) and Very Low-Density Lipoprotein (VLDL)(r = - 0.418), showed higher BDI scores (p<0.05).

CONCLUSIONS

We can conclude that there is a significant relationship between low TC and depression. Similarly, low levels of serum LDL, TG and VLDL also showed significant relationship with depression. Lipid levels below a certain limit are not good as it may cause depression. Patients with low lipid levels should be screened for depression so that if necessary, corrective measures can be taken at the earliest.

The effects of low/high fat diets and simple/complex carbohydrate intake on specific aspects of plasma VLDL and LDL metabolism were evaluated. Guinea pigs were fed for 4 wk two different fat/carbohydrate concentrations: 2.5/58 (g/100 g) or 25/29 (g/100 g) with either sucrose or cornstarch as the sole carbohydrate source. Intake of high fat diets resulted in higher plasma cholesterol (P < 0.001), whereas sucrose intake resulted in higher plasma triacyglycerol (TAG) concentrations (P < 0.03). Intake of starch increased apolipoprotein (apo) B secretion rates (P < 0.001), and nascent VLDL were smaller and contained less TAG/apo B than particles from the sucrose-fed group (P < 0.01). Guinea pigs fed the starch diets had higher plasma VLDL apo B flux and faster VLDL apo B clearance than those fed sucrose diets (P < 0.01). In addition, more rapid VLDL removal from plasma in guinea pigs fed complex carbohydrate/high fat diets was associated with less conversion of VLDL to LDL and lower plasma cholesterol concentrations compared with the high fat/sucrose group (P < 0.01). Low fat compared with high fat intake resulted in 60% more rapid plasma LDL apo B fractional catabolic rates (FCR). The LDL apo B fractional catabolic rate of all dietary groups was inversely correlated with plasma cholesterol concentrations (r = -0.83, P < 0.001). These results demonstrate that in guinea pigs, low fat diets decrease plasma LDL cholesterol concentrations by increasing LDL turnover rates, and complex carbohydrates reduce plasma TAG by affecting the composition of nascent VLDL particles and by increasing VLDL apo B catabolism.

The chemical composition and the physical properties of lipoproteins (VLDL, LDL and HDL) were studied in two groups of patients: 14 healthy normolipidemic subjects and 15 type IIa familial hypercholesterolemic patients. The steady-state fluorescence anisotropy rs was estimated in lipoproteins by the fluorescence depolarization of two fluorescent probes: the DPH (1,6-diphenyl-1,3,5-hexatriene) and the TMA-DPH (1,4-trimethylammonium phenyl-6-1,3,5-hexatriene). A structured order parameter S was calculated from the DPH fluorescence anisotropy. The flow activation energies were calculated for LDL and HDL from both groups from the Arrhenius plots (log r DPH versus 1/T). By using TNBS (trinitrobenzene sulfonic acid) as a distance control quencher, the two probes were located in the outer shell of LDL. In HDL, TMA-DPH remained at the surface of the particles, while DPH was more deeply embedded in the lipid core. There was no difference in the physico-chemical properties of VLDL between the two groups studied. DPH fluorescence anisotropies were significantly increased in LDL and HDL from the hypercholesterolemic group compared to the control particles (P less than 0.05 and P less than 0.01, respectively). In LDL this modification of the fluorescence anisotropy can be related to a change in the lipid composition of particles. LDL from hypercholesterolemic patients contained significantly less triacylglycerol (P less than 0.01) and more cholesteryl ester (N.S.). Their cholesteryl ester to triacylglycerol ratio was significantly higher. In HDL, there was no difference in chemical composition between the two groups. The increase in DPH fluorescence anisotropy can be related to the presence of smaller particles in HDL from HC group. No difference was noted in the TMA-DPH fluorescence anisotropy at 37 degrees C in the LDL from the two groups. In contrast, TMA-DPH fluorescence anisotropy in HDL from hypercholesterolemic group was significantly higher than in control HDL. The flow activation energy of DPH was also significantly higher in both LDL and HDL from the hypercholesterolemic group than in control group particles. In both LDL and HDL from the control group, DPH fluorescence anisotropy was negatively correlated with TG/protein and TG/PL ratios and positively correlated with the CE/TG ratio. No correlation was observed between lipid composition and DPH fluorescence anisotropy values in hypercholesterolemic particles. The modification in fluidity parameters, especially the increase in the flow activation energies in LDL and HDL from hypercholesterolemic patients, could lead to a restriction of cholesterol movements in these particles. From a physiological point of view, this could represent a loss of functional capacity.

OBJECTIVE

To analyze the metabonomic (1)H-MRS of plasma samples from patients with esophageal cancer and healthy controls applying different pattern recognition methods, and to explore the potential of application of (1)H-MR-based metabonomics in clinical research.

METHODS

(1)H-MR was performed on plasma samples from 109 EC patients and 50 health controls to analyze the metabonomic variation between EC patients and healthy subjects and the corresponding (1)H-MRS were recorded on Varian Unity ANOVA 600 MHz to perform principal components analysis (PCA), partial least squares discriminant analysis (PLS-DA), orthogonal partial least squares discriminant analysis (OPLS-DA), respectively.

RESULTS

OPLS-DA analysis could correctly separate almost all the plasma samples from EC patients and health controls, better than both the PCA and PLS-DA. The plasma levels of leucine, alanine, isoleucine, valine, glycoprotein, lactate, acetone, acetate, choline, isobutyrate, unsaturated lipid, VLDL, LDL, 1-methylhistidine were significantly decreased in EC patients (r total>> 0.27, P < 0.05), while that of dimethylamine, α-glucose, β-glucose, citric acid increased in the EC patients (r total < -0.27, P < 0.05).

CONCLUSIONS

The analysis of metabonomic (1)H-MRS of plasma samples by OPLS-DA method can eliminate the influence of non-experimental factors and decrease the heterogeneity of samples. It is useful and of great potential for application in clinical diagnosis and research of esophageal cancer.

OBJECTIVE

Oligo/amenorrhea, as a part of the Female Athlete Triad has adverse effects on the athlete's bone mineral density (BMD) and cardiovascular system. Hypoestrogenism, due to suppression of hypothalamus-pituitary axis (HPA) as a result of energy imbalance, is the possible cause of the Triad. This study was designed based on following up and reassessment of elite female athletes who were diagnosed as menstrual dysfunction about two years ago.

METHODS

THIS STUDY WAS CONDUCTED IN THREE PHASE SECTIONS: 1) Reassess the pattern of menstrual cycle among athletes who reported menstrual dysfunction about two years ago; 2) Bone mineral density was measured twice in the same machine and same center with a two-year interval; 3) The laboratory data including blood glucose, lipid profile and inflammatory markers was assessed in phase 3.

RESULTS

BMD of athletes did not change significantly after 25.5 months of oligomenorrhea P (spine) = 0.2, P (femur)=0.9. Mean of all cardiovascular factors was in the normal range except for high density lipoprotein (HDL) which was 49.28 (SD=9.18), however, most of the athletes had abnormalities in their lipid profile. Inverse relationship between the increase in the BMD of spine and total cholesterol (r =-0.49, P=0.04), Apolipoprotein A (r = -0.51 P=0.04), and very low density lipoprotein (VLDL) (r =-0.66, P=0.009). Also correlation between BMD of spine and HbA1C (r =-0.70, P=0.003) were significant.

CONCLUSIONS

Findings of this study show that negative changes in BMD and cardiovascular biomarkers of female athletes with functional hypothalamic menstrual dysfunction could occur if proper therapeutic intervention (including increase in calorie intake, decrease in exercise load or hormonal replacement) will not consider.

Because premenopausal women experience cyclic fluctuations of plasma carotenoids and their lipoprotein carriers, it was hypothesized that plasma alpha-tocopherol (A-T) fluctuates by phase of the menstrual cycle. Twelve free-living women, with a confirmed ovulatory cycle, were given a controlled diet for two consecutive menstrual cycles. Blood was drawn during the menses, early follicular, late follicular and luteal phases to simultaneously measure serum hormones, plasma lipoproteins and A-T concentrations, and A-T distribution in the lipoprotein fractions. Plasma A-T concentrations were significantly lower during menses than during the luteal phase by approximately 12% in each controlled diet cycle (P < 0.001). Adjustment for serum cholesterol and triglyceride concentrations did not alter these findings. The distributions of A-T in lipoprotein cholesterol fractions were not significantly different by menstrual phase. From 61 to 62% of A-T was concentrated in the LDL fraction, with another 9-14% in HDL2, 17-22% in HDL3 and the remaining 6-8% in VLDL+ IDL. There were no significant differences in lipoprotein cholesterol fractions by menstrual phase, except for a significant increase (P = 0.03) in HDL2 cholesterol from the early follicular to the late follicular phase. Spearman rank correlations from data during the second controlled diet month showed A-T in HDL2 in the late follicular phase was positively correlated with HDL cholesterol in the early follicular (r = 0.88), late follicular (r = 0.86) and luteal phases (r = 0.86) and with luteal apolipoprotein (ApoA-1) level (r = 0.90), and luteal HDL2 cholesterol (r = 0.83). A-T in HDL3 in the early follicular phase was negatively correlated with HDL2 cholesterol (r = -0.96) and ApoA-1 (r = -0.85), whereas luteal A-T in HDL3 was correlated with luteal HDL3 cholesterol (r = -0.79). Late follicular A-T in VLDL was positively correlated with early follicular HDL3 cholesterol and late follicular HDL3 cholesterol (r = 0.83). Fluctuations of A-T concentrations by phase of the menstrual cycle should be taken into consideration in future research concerning premenopausal women and the risk of chronic disease.

The present study aimed to investigate visceral adipose tissue-specific serpin (vaspin) concentrations in serum and term placentas and relate these values to insulin resistance and lipid parameters in women with gestational diabetes mellitus (GDM). A total of 30 GDM subjects and 27 age-matched pregnant women with normal glucose tolerance (NGT, control) were included. Serum glucose, glycated hemoglobin (HbA1c), lipid profile, insulin, and vaspin were measured at the end of pregnancy, and homeostasis model of assessment-insulin resistance (HOMA-IR) values were calculated. Vaspin mRNA and protein levels in placentas were measured by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blotting, respectively. Serum vaspin levels were significantly lower in the GDM group than in controls (0.49 ± 0.24 vs 0.83 ± 0.27 ng/mL, respectively; P<0.01). Three days after delivery, serum vaspin levels were significantly decreased in subjects with GDM (0.36 ± 0.13 vs 0.49 ± 0.24 ng/mL, P<0.01). However, in the GDM group, serum vaspin levels were not correlated with the parameters evaluated. In contrast, in the control group, serum vaspin levels were positively correlated with triglycerides (TG; r=0.45, P=0.02) and very low-density lipoprotein cholesterol (VLDL-C; r=0.42, P=0.03). Placental mRNA vaspin (0.60 ± 0.32 vs 0.68 ± 0.32, P=0.46) and protein (0.30 ± 0.08 vs 0.39 ± 0.26; P=0.33) levels in the GDM group did not differ significantly from those in the control group, but were negatively correlated with neonatal birth weight in the GDM group (r=-0.48, P=0.03; r=-0.88; P<0.01). Our findings indicated that vaspin may be an important adipokine involved in carbohydrate and lipid metabolism and may also play a role in fetal development.

BACKGROUND

Analysis of metabolic alterations and body composition in adolescents.

OBJECTIVE

To study the correlation of serum levels of lipids, glycemia, insulin, homocysteine, HOMA-IR and blood pressure among themselves and with body variables.

METHODS

Data concerning glycemia, total cholesterol and fractions (LDL, HDL and VLDL), triacylglycerols, insulin, homocysteine and blood pressure were measured in 100 adolescents at the age range of 14 to 17 years, who had already had menarche and attended the public schools in Vicosa, state of Minas Gerais, Brazil. The percentage of body fat (%BF) was evaluated by horizontal bioimpedance.

RESULTS

In relation to nutritional status, 83%, 11% and 6%, respectively were eutrophic (EU), presented overweight/overweight risk (OW/OR) or low weight (LW) (CDC/NCHS, 2000) and 61% presented high percentage of BF. Total cholesterol presented the highest percentage of inadequacy (57%), followed by HDL (50%), LDL (47%) and triacylglycerols (22%). Inadequacy in 11%, 9%, 5% and 4% were observed in relation to insulin resistance, insulin, blood pressure and glycemia, respectively. For total cholesterol, insulin, HOMA-IR and nutritional state, OW/OR>LW (p<0.05). For body composition and nutritional status, OW/OR>EU>LW (p <0.001). Some positive and strong correlations were found between BMI and the anthropometrical measures estimating the % of total BF, as well as central distribution, except for the waist/hip ratio. The %BF was correlated with insulin levels (r=0.303; p <0.001) and HOMA-IR (r=0.281; p<0.001).

CONCLUSIONS

Some metabolic alterations, most often related with excess weight and body fat as well as insulin resistance were found, reinforcing the importance of specific programs directed at the adolescent health.

We have identified a new truncated apolipoprotein B (apoB) that provides insights into the interaction of apoB with apo[a] and with lipids. Both total and LDL-cholesterol were below the 5th percentile in the proband; Lp[a] was 28 mg/dl. Four other affected individuals were identified in this kindred. Immunoblotting of plasma apoB-containing lipoproteins with an anti-apoB monoclonal antibody revealed a major band for apoB-100 and a minor band with apparent M(r) 217 kDa. The apoB truncation is due to a -1 frameshift mutation, consisting of a cytosine deletion at cDNA position 5444, that results in the translation of 22 novel amino acids terminating at residue 1767. The mutation was confirmed in the affected subjects by allele-specific oligonucleotide (ASO) analysis. Gel filtration of whole plasma revealed that the minority of apoB-38.9 eluted with IDL- and LDL-sized particles, while the majority (approximately 60%) eluted between LDL and HDL. Lp[a] eluted between VLDL and LDL. Upon preparative density gradient ultracentrifugation (DGUC), the majority of the plasma apoB-38.9 (approximately 65%) floated at a density of 1.12 g/ml coincident with the major peak of HDL cholesterol. Lp[a] floated at a peak density of 1.08 g/ml between LDL and HDL. Immunoblots of the apoB-38.9-containing HDL density DGUC fractions subjected to nondenaturing gradient gel electrophoresis (GGE) demonstrated two apoB-38.9-containing particle populations with diameters of approximately 15 nm and approximately 18 nm, respectively. Lipoproteins of these sizes were also detected when whole plasma was subjected to GGE and immunoblotting. The 15-18 nm lipoproteins correspond to the gel filtration populations eluting between LDL and HDL. Lysine-Sepharose chromatography of plasma yielded retained products that contained apo[a] and apoB-100 but not apoB-38.9. Immunoprecipitation of whole plasma with monospecific polyclonal anti-human apo[a] showed apo[a] and apoB-100, but no apoB-38.9 to be present in precipitates. ApoB-100 and apoB-38.9 were present in supernates. In in vitro incubations, recombinant apo[a] formed complexes with apoB-100 but not with apoB-38.9-containing particles. Our results show that the apoB-38.9 protein can be found in a variety of lipoproteins; however, the majority of apoB-38.9-containing lipoproteins float at a density equivalent to HDL but are larger than HDL, being intermediate in size between apoB-100 LDL and HDL. The heterogeneity of apoB-38.9 lipoproteins may reflect their dual tissue source, i.e., liver and intestine, and the discordance between size and density indicates a disproportionately reduced association of lipids with apoB-38.9. Finally, our data suggest that apoB-38.9 is incapable of forming complexes with apo[a] in plasma.

<p><div><b>OBJECTIVE</b></div>Epica<em>r</em>dial adipose tissue (EAT) is an active endoc<em>r</em>ine o<em>r</em>gan that could cont<em>r</em>ibute to the pathophysiology of co<em>r</em>ona<em>r</em>y a<em>r</em>te<em>r</em>y disease (CAD) th<em>r</em>ough the pa<em>r</em>ac<em>r</em>ine <em>r</em>elease of p<em>r</em>oathe<em>r</em>ogenic mediato<em>r</em>s. Nume<em>r</em>ous wo<em>r</em>ks have analyzed the inflammato<em>r</em>y signatu<em>r</em>e of EAT, but sca<em>r</em>ce info<em>r</em>mations on its lipidome a<em>r</em>e available. Ou<em>r</em> objective was fi<em>r</em>st to study the diffe<em>r</em>ences between EAT and subcutaneous adipose tissue (SAT) lipidomes and second to identify the specific unta<em>r</em>geted lipidomic signatu<em>r</em>es of EAT and SAT in CAD. App<em>r</em>oach and Results: Subcutaneous and EAT unta<em>r</em>geted lipidomic analysis was pe<em>r</em>fo<em>r</em>med in 25 patients with CAD and 14 patients without CAD and compa<em>r</em>ed with pai<em>r</em>ed plasma lipidomic analysis of isolated <em>VLDL</em> (ve<em>r</em>y low-density lipop<em>r</em>otein) and HDL (high-density lipop<em>r</em>otein). Lipidomics was pe<em>r</em>fo<em>r</em>med on a C18 column hyphenated to a Q-Exactive plus mass spect<em>r</em>omete<em>r</em>, using both positive and negative ionization mode. EAT and SAT had independent lipidomic p<em>r</em>ofile, with 95 lipid species diffe<em>r</em>entially exp<em>r</em>essed and phosphatidylethanolamine 18:1p/22:6 twenty-fold mo<em>r</em>e exp<em>r</em>essed in EAT compa<em>r</em>ed with SAT false discove<em>r</em>y <em>r</em>ate =3×10^-4). Patients with CAD exhibited mo<em>r</em>e ce<em>r</em>amides (<i>P</i>=0.01), diglyce<em>r</em>ides (<i>P</i>=0.004; satu<em>r</em>ated and nonsatu<em>r</em>ated), monoglyce<em>r</em>ides (<i>P</i>=0.013) in thei<em>r</em> EAT than patients without CAD. Conve<em>r</em>sely, they had lesse<em>r</em> unsatu<em>r</em>ated TG (t<em>r</em>iglyce<em>r</em>ides; <i>P</i>=0.02). No diffe<em>r</em>ence was obse<em>r</em>ved in the 295 lipid species found in SAT between patients with and without CAD. Fifty-one lipid species we<em>r</em>e found in common between EAT and plasma lipop<em>r</em>oteins. TG 18:0/18:0/18:1 was found positively co<em>r</em><em>r</em>elated (<i><em>r</em></i>=0.45, <i>P</i>=0.019) in EAT and HDL and in EAT and <em>VLDL</em> (<i><em>r</em></i>=0.46, <i>P</i>=0.02).</p><Abst<em>r</em>actText>CAD is associated with specific lipidomic signatu<em>r</em>e of EAT, unlike SAT. Plasma lipop<em>r</em>otein lipidome only pa<em>r</em>tially <em>r</em>eflected EAT lipidome.</Abst<em>r</em>actText>

BACKGROUND

Chronic kidney disease (CKD) patients are at a high risk of dying from a cardiovascular event, mainly due to coronary calcification. Among the various uremic and dialysis-specific risk factors for coronary calcification are mineral metabolism disorders. The role that secondary hyperparathyroidism (SHPT) consequent to the altered calcium and phosphate metabolism plays in the pathogenesis of coronary calcification remains unclear. The aim of this study was to evaluate the prevalence of coronary artery calcification in dialysis patients with severe SHPT submitted to multislice coronary tomography (MSCT) and to identify risk factors for coronary calcification.

METHODS

This study involved 23 adult dialysis patients (age >18 years) with severe SHPT who were candidates for parathyroidectomy (PTX). All were submitted to MSCT and bone densitometry during the month preceding PTX. Fasting blood samples were collected immediately before surgery. Markers of mineral metabolism, including ionized calcium, phosphorus, alkaline phosphatase, intact-parathyroid hormone (iPTH), osteoprotegerin (OPG) and soluble receptor activator of nuclear factor-kappaB ligand, were analyzed. Dyslipidemia was assessed by determination of LDL, HDL and VLDL-cholesterol and triglyceride levels. Agatston units (AU) were used to calculate calcium scores.

RESULTS

No coronary calcification was found in 30% of the patients. Moderate (calcium score>> 100 AU) and severe (calcium score >400 AU) calcification was observed in 12 and 36% of the patients, respectively. In the univariate analysis, calcium volume correlated positively with VLDL-cholesterol (r = 0.44; p = 0.03) and, albeit less than significantly, with age (r = 0.35; p = 0.09), triglycerides (r = 0.39; p = 0.05) and Framingham risk index (r = 0.37; p = 0.07). We also found that OPG correlated negatively with bone mineral density at the L2-L4 lumbar vertebrae (r = -0.54; p = 0.007) and femoral neck (r = -0.43; p = 0.04).

CONCLUSIONS

Although high levels of PTH should be considered a risk factor for cardiovascular death, the real role of severe SHPT on coronary calcification is to be clarified.

BACKGROUND

Factor VII coagulant activity (VIIc) is implicated in cardiovascular disease (CVD) risk in the general population. VIIc is correlated with hyperlipidaemia and influenced by a polymorphism of the factor VII gene and could contribute to thrombotic risk in patients with renal disease.

METHODS

We studied VIIc in 100 patients with chronic renal disease or on maintenance dialysis and examined its relationship with dyslipidaemia, a marker of coagulation activation prothrombin fragment F1+2 (F1+2), the acute-phase reactant and coagulation factor fibrinogen, a mediator of the inflammatory response interleukin-6 (IL6), and the factor VII R353Q polymorphism.

RESULTS

VIIc (186+/-58 vs 140+/-37, % standard, P<0.0001) and F1+2 (0.51 vs 0.30 nM, median, P<0.0001) were increased in the patients with renal disease compared with the control group, consistent with a hypercoagulable state. Patients and controls heterozygous for the factor VII R353Q polymorphism, had 35% lower VIIc than homozygotes for the R353 allele, indicating that the Q353 allele could confer genetic protection from thrombotic risk. There was a significant correlation between VIIc and F1+2 (r=0.26, P<0.05), total and VLDL cholesterol, and triglycerides, but the correlation with lipids did not differ by genotype. VIIc and F1+2 also correlated with increased concentration of IL6 and fibrinogen, and inversely with albumin, suggesting that a persistent inflammatory response could contribute to a hypercoagulable state, possibly via cytokine induced activation of the endothelium, or by induction of monocytes to express tissue factor. Patients with CVD complications or a history of myocardial infarction did not have higher VIIc or F1+2 than those without CVD.

CONCLUSIONS

VIIc was significantly increased in renal disease states and strongly influenced by a common polymorphism of the factor VII gene, but the increase in VIIc and its correlation with lipids was not genotype specific. VIIc correlated with evidence of increased coagulation activation and persistence of an inflammatory response. A persistent inflammatory response and the dyslipidaemia of renal disease may contribute to coagulation activation and increased cardiovascular risk. Prospective studies are required to evaluate increased VIIc as a thrombotic risk factor in chronic renal disease.

The effects of hemodialysis duration (HD) on lipoprotein lipase (LPL) and hepatic lipase (HL) activities and very low density lipoprotein (VLDL), low density lipoproteins (LDL) amounts and compositions were investigated in 58 patients, divided according to HD: GI: under 1 year, GII: 1-5 years, GIII: 5-13 years. HL and LPL activities were reduced in GIII versus GI (P<0.01) and 47% of GIII patients had negligible HL activity. LPL and HL activities were correlated with HD (r=-0.80, P<0.001). Apo C-III concentrations were correlated with HD (r=0.58, P<0.05). Compared with controls, triacylglycerols (TG) were increased in GI, GII (P<0.01) and GIII (P<0.001), and were correlated with HD (r=0.75, P<0.05). VLDL amounts and VLDL-cholesteryl esters (CE) were enhanced in GIII versus GI and GII (P<0.05). VLDL-TG and VLDL-phospholipids (PL) were correlated with HD (r=0.60, P<0.05). LDL-apolipoproteins and unesterified cholesterol (UC) were increased in GII versus GI (P<0.05) and in GIII versus GII and GI (P<0.01). LDL-PLs were decreased in GIII versus GI (P<0.05). Compared with controls, LDL-TGs were higher in GI and GII (P<0.01) and in GIII (P<0.05). Long-term treatment with acetate hemodialysis using cuprophane membrane does not improve lipolytic activity decrease and lipoprotein alterations generated by chronic renal failure (CRF).

Remnant-Like Particles (RLP) isolated by an immunoseparation method are heterogeneous in their physical and biochemical properties. The objective of this study was to examine the relation between RLP-triglyceride (RLP-TG) to RLP-cholesterol (RLP-C) ratio and particle size distribution in RLP-C profiles from patients with hyperlipoproteinemia by HPLC. RLP were isolated from serum samples from 147 subjects. RLP-C and RLP-TG were quantified by respective enzymatic methods. Particle sizes of the RLP were measured using HPLC with 4 connected TSKgel LipopropakXL columns. Based on HPLC profiles of RLP-C from individual subjects, three different types were classified: predominantly LDL, predominantly VLDL, and mostly VLDL types. All patients with type III hyperlipidemia were mostly VLDL type but with smaller particle size of VLDL (32 nm) than other subjects. Severe hypertriglyceridemic (TG>4.52 mmoll(-1)) subjects were mostly VLDL type with large particle size (41 nm). As for all subjects (n=105) without predominantly LDL type, a significant correlation between RLP particle size and RLP-TG to RLP-C ratio (r=0. 432, P<0.001) was obtained, but not in case of serum TG to RLP-C ratio (r=0.062). It suggests that RLP-TG to RLP-C ratio might be used for discrimination of atherogenic smaller-sized lipoprotein from larger-sized TG-rich lipoprotein remnants.

We previously established an analysis method for determining the cholesterol levels of five major lipoprotein classes [HDL, LDL, intermediate density lipoprotein (IDL), VLDL, and chylomicrons] in serum by an anion-exchange (AEX)-HPLC method, but lipoprotein(a) [Lp(a)], a well-known risk factor for atherosclerotic diseases, was not determinable. Therefore, we established new AEX-HPLC separation conditions for analyzing the cholesterol levels of six lipoprotein classes, including Lp(a). Serum lipoproteins were separated by HPLC with a diethylaminoethyl-ligand nonporous polymer-based column by elution with a stepwise gradient of the sodium perchlorate concentration. In this improved method, HDL, LDL, IDL, VLDL, chylomicrons, and Lp(a) were each eluted from the column. The cholesterol levels of the eluted lipoproteins were measured enzymatically by a postcolumn reaction. The within-day assay and between-day assay coefficients of variation for the lipoprotein cholesterol levels were in the ranges of 0.29-11.86% and 0.57-11.99%, respectively. The Lp(a) cholesterol levels determined by AEX-HPLC were significantly correlated with the amounts of Lp(a) protein measured by an immunoturbidimetry method available commercially (r = 0.9503, P < 0.0001). Taken together, this AEX-HPLC method may be effectively applied to the analysis of serum lipoproteins with high levels of Lp(a).