Nephrotic syndrome (NS) is characterized by the presence of proteinuria and hyperlipidemia. However, ingestion of soy protein has a hypolipidemic effect. The present study was designed to determine whether the ingestion of a 20% soy protein diet regulates the expression of hepatic sterol regulatory element binding protein (SREBP)-1, fatty acid synthase (FAS), malic enzyme, beta-hydroxy-beta-methylglutaryl-CoA (HMG-CoA) reductase (r) and synthase (s), and LDL receptor (r), and to assess whether soy protein improves lipid and renal abnormalities in rats with chronic NS. Male Wistar rats were injected with vehicle or with puromycin aminonucleoside to induce NS and were fed either 20% casein or soy protein diets for 64 d. NS rats fed 20% soy protein had improved creatinine clearance and reduced proteinuria, hypercholesterolemia, hypertriglyceridemia, as well as VLDL-triglycerides and LDL cholesterol compared with NS rats fed the 20% casein diet. In addition, the soy protein diet decreased the incidence of glomerular sclerosis, and proinflammatory cytokines in kidney. Ingestion of the soy protein diet by control rats reduced the gene expression of SREBP-1, malic enzyme, FAS and increased HMG-CoAr, HMG-CoAs and LDLr. However, NS rats fed either casein or soy protein diets had low insulin concentrations with reductions in SREBP-1, FAS and malic enzyme expression compared with control rats fed the casein diet. NS rats fed the soy diet also had lower HMG-CoAr and LDLr mRNA levels than NS rats fed casein. In conclusion, the beneficial effects of soy protein on lipid metabolism are modulated in part by SREBP-1. However, in NS rats, the benefit may be through a direct effect of this protein on kidney rather than mediated by changes in expression of hepatic lipid metabolism genes.

Our aim is to investigate visfatin concentration and its relationship to glycated hemoglobin (HbA1c), insulin resistance, lipid parameters, and neonatal birth weight in women with gestational diabetes mellitus (GDM). In our study group, there were 47 women with GDM and 31 women with normal glucose tolerance (NGT) between 33-39 weeks of gestation. Plasma visfatin levels were significantly decreased in pregnant women with GDM compared to those with NGT (p=0.001). Homeostasis model assessment-insulin resistance (HOMA-IR) levels were higher in the GDM group than in the NGT group (p=0.006). In all subjects, plasma visfatin levels were negatively correlated with HOMA-IR, post-prandial blood glucose, triglycerides, and VLDL cholesterol (p<0.05). We did not observe any statistically significant correlation between the plasma visfatin levels and the selected parameters in the GDM group, but in the NGT group plasma visfatin levels were negatively correlated with HOMA-IR (r=-0.36, p=0.04). There was no correlation between visfatin concentrations and fetal birth weight in either group (p>0.05). By regression analysis, having GDM was found to be the only significant determinant (t=3.5, p=0.001) of visfatin concentration (R=0.39, rreased visfatin concentrations in the third trimester. Future studies are required to establish the exact role of visfatin in the pathogenesis of GDM.

Low density lipoprotein (LDL) particles are heterogeneous in size, density, and chemical composition; small, dense LDL may be more atherogenic than large, buoyant LDL. We have developed a rapid microscale method called LDL VAP-II (Vertical Auto Profile-II) for quantification of cholesterol in LDL subclasses. The method is based upon a short (1 h) single vertical spin density-gradient ultracentrifugation and on-line VAP-II analyzer. LDL VAP-II is rapid and reproducible. Using this method five LDL subclasses, designated as LDL-1 (most buoyant) through LDL-5 (most dense), have been identified in a population consisting of 195 medical students (ages, 22-29 years). The Rf (relative position of the major LDL peak in the density gradient; the higher the Rf value, the lower the peak density) was significantly positively correlated with cholesterol levels of high density lipoprotein (HDL) (r = 0.594), HDL3 (0.350) and HDL2 (0.625), and significantly negatively correlated with triglycerides (TG) (-0.355) and cholesterol levels of very low density lipoprotein (VLDL) (-0.386) and intermediate density lipoprotein (IDL) (-0.432). These results are consistent with those obtained by other investigators. The Rf value was significantly correlated with peak particle diameter as determined by non-denaturing gradient gel electrophoresis (r = 0.859). In a forward stepwise multivariate analysis comparing Rf with sex, VLDL, LDL, Lp[a], IDL, HDL3, HDL2, and triglyceride, only HDL2 remained in the model.

Carbohydrate-induced hypertriglyceridemia is easily produced in the rat, and fructose has been shown to be particularly potent in this regard. In this study we have compared the effects of feeding rats diets high (66% of total calories) in fructose or glucose on various aspects of carbohydrate and lipid metabolism. The results confirmed previous observations that fructose (456 +/- 276 mg/dl) was more potent (p less than 0.001) in raising plasma TG concentration than was glucose (242 +/- 13 mg/dl), and indicated that the difference in magnitude of hypertriglyceridemia produced by the two carbohydrates was closely related to the ability of the test diets to increase VLDL-TG secretion (r = 0.85, p less than 0.001). Both glucose and fructose feeding led to comparable degrees of hyperinsulinemia, and plasma TG concentrations increased before hyperinsulinemia evolved in fructose-fed rats. Therefore, it was concluded that fructose can act directly on the liver to increase VLDL-TG secretion, and that fructose-induced hypertriglyceridemia can occur in the absence of hyperinsulinemia. On the other hand, the rise in plasma TG concentration produced by fructose was reduced dramatically in exercise-trained rats, and this was associated with a decrease in plasma insulin concentration. Based upon these observations, we suggest that fructose feeding produces hypertriglyceridemia by directly stimulating hepatic VLDL-TG secretion, as well as by producing insulin resistance and hyperinsulinemia, and that it is the combined effect of these two separate actions which accounts for the magnitude of fructose-induced hypertriglyceridemia.

OBJECTIVE

To examine the association between liver fat content and very low-density lipoprotein (VLDL)-apolipoprotein (apo) B-100 kinetics and the corresponding responses to weight loss in obese subjects.

RESULTS

VLDL-apoB-100 kinetics were assessed using stable isotope tracers, and the fat content of the liver and abdomen was determined by magnetic resonance techniques in 25 obese subjects. In univariate analysis, liver fat content was significantly (P<0.05 in all) associated with body mass index (r=0.65), visceral fat area (r=0.45), triglycerides (r=0.40), homeostasis model assessment score (r=0.40), VLDL-apoB-100 concentrations (r=0.44), and secretion rate (r=0.45). However, liver fat content was not associated with plasma concentrations of retinol-binding protein 4, fetuin A, adiponectin, interleukin-6, and tumor necrosis factor-alpha. Of these 25 subjects, 9 diagnosed as having nonalcoholic fatty liver disease (which is highly prevalent in obese individuals and strongly associated with dyslipidemia) underwent a weight loss program. The low-fat diet achieved significant reduction in body weight, body mass index, liver fat, visceral and subcutaneous fat areas, homeostasis model assessment score, triglycerides, VLDL-apoB-100 concentrations, and VLDL-apoB-100 secretion rate. The percentage reduction of liver fat with weight loss was significantly associated with the corresponding decreases in VLDL-apoB-100 secretion (r=0.67) and visceral fat (r=0.84).

CONCLUSIONS

In patients with obesity, hepatic steatosis increases VLDL-apoB-100 secretion. Weight loss can help reduce this abnormality.

We examined the effects of dietary fats with specific fatty acid compositions, on serum paraoxonase (PON1) activity in rats. Male adult Sprague-Dawley rats were divided randomly into four dietary groups. One group received the control diet [AIN 93M with soybean oil (5 g/100 g diet)], whereas the remaining three groups received the modified control diet supplemented with (15 g/100 g diet) triolein, tripalmitin or fish oil, respectively. After 20 d, blood was obtained after overnight food deprivation and PON1 activity was determined. Serum lipids and lipid components of lipoproteins were also determined. Serum PON1 activity [micromol/(L.min)] was significantly (P: < 0.05) higher in triolein (98 +/- 6) and lower in fish oil (41 +/- 4), compared with tripalmitin-fed rats (63 +/- 11). Serum PON1 activity in tripalmitin-fed rats was comparable to that of controls (67 +/- 9). Serum PON1 activity correlated significantly with serum lecithin:cholesterol acyltransferase (LCAT) activity (r = 0.77, P: < 0.001) and was transported in blood principally in association with the denser subfraction of HDL, very high density lipoprotein (VHDL; d>> 1.15 kg/L). Serum PON1 activity correlated strongly with serum lipids as well as lipids of VLDL, HDL and its subfractions. Multiple linear regression analysis, however, showed a significant relationship of serum PON1 activity, principally with the phospholipids of VHDL (r = 0.47, P: < 0.002). These data suggest that the modulation of serum PON1 activity by dietary fat may be mediated via the effect of the specific fatty acids on the synthesis and secretion of VHDL, the subfraction of HDL that transports the majority of PON1 in the blood.

BACKGROUND

Transport of fatty acids within the cytosol of adipocytes and their subsequent assimilation into lipid droplets has been thoroughly investigated; however, the mechanism by which fatty acids are transported across the plasma membrane from the extracellular environment remains unclear. Since triacylglycerol-rich lipoproteins represent an abundant source of fatty acids for adipocyte utilization, we have investigated the expression levels of cell surface lipoprotein receptors and their functional contributions toward intracellular lipid accumulation; these include very low density lipoprotein receptor (VLDL-R), low density lipoprotein receptor-related protein (LRP), and heparan sulfate proteoglycans (HSPG).

RESULTS

We found that expression of these three lipoprotein receptors increased 5-fold, 2-fold, and 2.5-fold, respectively, during adipocyte differentiation. The major proteoglycans expressed by mature adipocytes are of high molecular weight (>500 kD) and contain both heparan and chondroitin sulfate moieties. Using ligand binding antagonists, we observed that HSPG, rather than VLDL-R or LRP, play a primary role in the uptake of DiI-labeled apoE-VLDL by mature adipocytes. In addition, inhibitors of HSPG maturation resulted in a significant reduction (>85%) in intracellular lipid accumulation.

CONCLUSIONS

These results suggest that cell surface HSPG is required for fatty acid transport across the plasma membrane of adipocytes.

The aim of this study was to characterize abnormalities of triglyceride-rich apolipoprotein (apo) B-containing lipoproteins in type I diabetic patients with elevated albumin excretion rates (AERs). Sixty-four patients (31 men, 33 women) with normoalbuminuria (AER <20 microg/min), 52 (35 men, 17 women) with microalbuminuria (AER 20-200 microg/min), and 37 (17 men, 20 women) with albuminuria (AER >200 microg/min) and 56 healthy control subjects matched for age and body weight were studied. The major finding was increased mass concentrations of the highly atherogenic intermediate-density lipoprotein fraction in patients with microalbuminuria (P < 0.05) and albuminuria (P < 0.05), compared with those with normoalbuminuria. Triglyceride, free cholesterol, cholesterol ester, and phospholipid concentrations in the VLDL, intermediate-density lipoprotein, and LDL (P < 0.05-0.01), as well as total cholesterol, total triglyceride, and apoB concentrations were higher in patients with renal disease than in those without. Notably, there were no differences between patients with microalbuminuria and albuminuria. Only minor compositional changes could be detected. Postheparin plasma lipoprotein lipase (LPL) activities were identical, but hepatic lipase activities were higher in microalbuminuric and albuminuric patients than in normoalbuminuric patients (P < 0.01). LPL activity and VLDLr = -0.528; P < 0.001) and VLDLrations (r = -0.471; P < 0.001) were negatively related. In conclusion, in type I diabetic patients with early renal disease, there are multiple lipoprotein changes, which are potentially atherogenic and may contribute to the excess of macrovascular complications seen in such patients.

BACKGROUND

Quantification of triglyceride-rich lipoprotein (TRL) remnants is useful for risk assessment of coronary artery disease and the diagnosis of type III hyperlipoproteinemia. Although an immunoseparation procedure for remnant-like particle cholesterol has been evaluated extensively in recent years, available methods for measuring TRL remnants have not achieved wide use in routine laboratory practice, suggesting a need for a homogeneous assay that can measure TRL remnant cholesterol in serum or plasma without pretreatment.

METHODS

We screened for suitable surfactants that exhibited favorable selectivity toward the VLDL remnant (VLDLR) fraction, including intermediate-density lipoproteins (IDLs). We investigated the principal characteristics of this assay by gel filtration of lipoproteins and their particle size distribution. We developed a simple assay and evaluated its performance with the Hitachi-7170 analyzer.

RESULTS

Polyoxyethylene-polyoxybutylene block copolymer (POE-POB) exhibited favorable selectivity toward VLDLR and IDL fractions. POE-POB removed apolipoprotein (apo) E and apo C-III from IDL particles in the presence of cholesterol esterase (CHER), and the particle size distribution of IDLs became smaller after the reaction. These results revealed that IDL particles are specifically modified in the presence of CHER and POE-POB, making their component cholesterol available for enzymatic assay. Addition of phospholipase D improved the reactivity toward chylomicron remnants (CMRs). We found a high correlation [y = 1.018x- 0.01 mmol/L, r = 0.962 (n = 160)] between the proposed assay and the immunoseparation assay in serum from healthy individuals.

CONCLUSIONS

The homogeneous assay described in this report can measure TRL remnant cholesterol, including CMRs, VLDLRs, and IDLs, with high sensitivity and specificity.

The primary purpose of this investigation was to determine whether adipose tissue glycerol 3-phosphate dehydrogenase activity is associated with human obesity. The data presented in this paper indicate that the glycerol 3-phosphate dehydrogenase activity in adipose tissue from morbidly obese subjects is approximately 2-fold higher than from lean individuals. Moreover, positive correlation between adipose tissue glycerol 3-phosphate dehydrogenase activity and body mass index (BMI) (r = 0.5; p < 0.01) was found. In contrast, the adipose tissue fatty acid synthase (FAS) and ATP-citrate lyase (ACL) activities in morbidly obese patients are significantly lower than in lean subjects. Furthermore, negative correlation between adipose tissue FAS activity and BMI (r = -0.3; p < 0.05) as well as between ACL activity and BMI (r = -0.3; p < 0.05) was found. These data indicate that elevated glycerol 3-phosphate dehydrogenase might contribute to the increase of triacylglycerol (TAG) synthesis in obese subjects, however, fatty acids necessary for glycerol 3-phosphate esterification must be derived (because of lower FAS and ACL activities) mainly from TAG in circulating lipoproteins formed in liver (VLDL), and/or from the intake with food (chylomicrons). The conclusion is, that the enhanced activity of glycerol 3-phosphate dehydrogenase, and hence the generation of more glycerol 3-phosphate in adipose tissue offers a novel explanation for increased TAG production in adipose tissue of obese subjects.

OBJECTIVE

To define the pathophysiologic characteristics of patients at high risk for coronary heart disease due to an increased ratio of total cholesterol (TC) to high density lipoprotein-cholesterol (HDL-C).

METHODS

Cross-sectional.

METHODS

Clinical Research Center.

METHODS

One hundred-20 healthy, non-diabetic, normotensive, volunteers were screened for this study. From this pool, 40 individuals (20 females and 20 males) with the highest and the lowest TC/HDL-C ratios were selected for comparison.

METHODS

Values for body mass index (BMI), ratio of waist to hip girth (WHR), and blood pressure were obtained on all patients. In addition, measurements were made of fasting lipid and lipoprotein concentrations, plasma glucose and insulin responses to an oral glucose challenge, and insulin resistance as assessed by the insulin suppression test.

RESULTS

Age, BMI, and WHR were the same in the two groups. However, the group with a high TC/HDL-C ratio had higher (P < 0.05) systolic and diastolic blood pressures. In addition, patients with a high TC/HDL-C ratio had significantly higher (P < 0.001) very low density (VLDL) and low density lipoprotein (LDL)-cholesterol concentrations and lower HDL-cholesterol concentrations, with significant (P < 0.001) correlations between the TC/HDL-C ratio and VLDL (r = 0.60), LDL (r = 0.54), and HDL (r = -0.73) cholesterol concentrations. Patients with a high TC/HDL-C ratio were also significantly (P < 0.05-0.001) more insulin resistant, glucose intolerant with a greater plasma insulin response to oral glucose, and hypertriglyceridemic.

CONCLUSIONS

The results indicate that an increase in LDL-cholesterol concentration is not necessarily the major contributor to a high ratio of TC/HDL-C. Furthermore, individuals with this epidemiologic designation are insulin resistant, and liable to all the other abnormalities associated with this metabolic defect.

BACKGROUND

Increasing evidence supports carbohydrate restricted diets (CRD) for weight loss and improvement in traditional markers for cardiovascular disease (CVD); less is known regarding emerging CVD risk factors. We previously reported that a weight loss intervention based on a CRD (% carbohydrate:fat:protein = 13:60:27) led to a mean weight loss of 7.5 kg and a 20% reduction of abdominal fat in 29 overweight men. This group showed reduction in plasma LDL-cholesterol and triglycerides and elevations in HDL-cholesterol as well as reductions in large and medium VLDL particles and increases in LDL particle size. In this study we report on the effect of this intervention with and without fiber supplementation on plasma homocysteine, lipoprotein (a) [Lp(a)], C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-alpha).

METHODS

Twenty nine overweight men [body mass index (BMI) 25-35 kg/m2] aged 20-69 years consumed an ad libitum CRD (% carbohydrate:fat:protein = 13:60:27) including a standard multivitamin every other day for 12 wk. Subjects were matched by age and BMI and randomly assigned to consume 3 g/d of either a soluble fiber supplement (n = 14) or placebo (n = 15).

RESULTS

There were no group or interaction (fiber x time) main effects, but significant time effects were observed for several variables. Energy intake was spontaneously reduced (-30.5%). This was accompanied by an increase in protein intake (96.2 +/- 29.8 g/d to 107.3 +/- 29.7 g/d) and methionine intake (2.25 +/- 0.7 g/d, to 2.71 +/- 0.78 g/d; P < 0.001). Trans fatty acid intake was significantly reduced (-38.6%) while dietary folate was unchanged, as was plasma homocysteine. Bodyweight (-7.5 +/- 2.5 kg) was reduced as was plasma Lp(a) (-11.3%). Changes in plasma Lp(a) correlated with reductions in LDL-cholesterol (r = .436, P < 0.05) and fat loss (r = .385, P < 0,05). At wk 12, both CRP (-8.1%) and TNF-alpha (-9.3%) were reduced (P < 0.05) independently of weight loss. IL-6 concentrations were unchanged.

CONCLUSIONS

A diet based on restricting carbohydrates leads to spontaneous caloric reduction and subsequent improvement in emerging markers of CVD in overweight/obese men who are otherwise healthy.

BACKGROUND

Platelet-activating factor acetylhydrolase (PAF-AH or Lp-PLA(2)) is a Ca(2+)-independent phospholipase A(2) primarily associated in plasma with low density lipoproteins (LDL), especially with small dense LDL (sdLDL) particles. Increased plasma Lp-PLA(2) levels have been associated with increased cardiovascular risk in large clinical trials.

OBJECTIVE

To assess the effects of weight loss on Lp-PLA(2) activity and to examine the association of Lp-PLA(2) activity changes with the alterations of sdLDL, the primary carrier of Lp-PLA(2) in plasma.

METHODS

Twenty-eight obese, non-diabetic women participated in a weight reduction program. Anthropometric parameters were assessed and parameters of glucose metabolism, lipid profile, Lp-PLA(2) activity, and LDL phenotype (using a 3% polyacrylamide gel-tube electrophoresis method), were determined at baseline and after 4months of weight loss.

RESULTS

A 10% diet-induced weight loss resulted in significant improvement in most parameters of lipid and glucose metabolism. Moreover, Lp-PLA(2) activity was significantly reduced (-10.2%, p<0.01). Mean LDL particle diameter did not change after the weight loss program. The cholesterol levels of very low-density lipoprotein (VLDL) and large-buoyant LDL particles were significantly reduced, but neither the cholesterol levels of sdLDL particles nor the % proportion of the sdLDL-cholesterol over the total LDL-cholesterol were changed after the intervention program. Interestingly, the changes in Lp-PLA(2) activity were correlated with the changes of VLDL-cholesterol (r=0.39, p<0.05), but not with the changes of anthropometric or other lipid variables.

CONCLUSIONS

A low-calorie diet associated with weight loss in obese women resulted in the significant reduction of the plasma levels of Lp-PLA(2), the potentially new predictor for incident atherosclerotic disease.

In epidemiologic studies, hyperinsulinemia has been found to be an independent risk factor for coronary heart disease (CHD). However, the mechanisms responsible for its role in atherogenesis remain unclear. We studied the relationship of in vivo insulin action and plasma lipids and lipoproteins in 44 normotriglyceridemic white men (aged 18 to 34 years). The euglycemic, hyperinsulinemic glucose clamp technique was used to quantitate insulin-mediated glucose disposal (M/I value) at a plasma insulin concentration of approximately 100 microU/mL. The M/I value correlated negatively with plasma triglycerides (r = -0.553, P less than .0001), as well as with fasting plasma insulin levels (r = -0.483, P less than .001), independent of age, body mass index, and fasting plasma glucose levels. A negative correlation of the M/I value was also observed with very low density lipoprotein (VLDL)-cholesterol (r = -0.347, P less than .05), VLDL-triglycerides (r = -0.474, P less than 0.005), and total cholesterol/high density lipoprotein (HDL)-cholesterol ratio (r = -0.431, P less than .01). The relationship between the M/I value and the total cholesterol/HDL-cholesterol ratio was independent of VLDL-cholesterol and VLDL-triglycerides, however, not independent of plasma triglycerides. No relationship was observed between insulin-mediated glucose uptake and total cholesterol, low density lipoprotein (LDL)-cholesterol, and HDL-cholesterol values. Individual differences in plasma triglycerides, fasting insulin concentration, and the total cholesterol/HDL-cholesterol ratio accounted for about half the variance observed in the M/I value.(ABSTRACT TRUNCATED AT 250 WORDS)

Our aim was to investigate whether trans-resveratrol (t-resveratrol), a red wine constituent known for its cardioprotective effects, was able to influence CD40 ligand (CD40L) and its receptor CD40 in platelets of hypercholesterolemic rats. Sixty Wistar rats were divided into 5 groups: control (C), ethanol (E), t-resveratrol (R), hypercholesterolemia (HC), and hypercholesterolemia plus t-resveratrol (HCR). Rats in the C, E, and R groups were fed a normal diet for 80 days. For 20 days before sacrifice, we intraperitoneally (i.p.) administered 0.1 mL ethanol (50% v/v) to the E group, and 0.1 mL t-resveratrol (20 mg·kg(-1)·day(-1)) to the R group. Rats in the HC and HCR groups were fed a 5% cholesterol diet for 80 days. Rats in the HCR group were administered i.p. 0.1 mL t-resveratrol (20 mg·kg(-1)·day(-1)) for 20 days before sacrifice. Serum levels of total cholesterol (TC), low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), very low-density lipoprotein (VLDL-C), and total triglycerides (TG) were assayed with a commercial colorimetric kit. Platelet P-selectin, CD40, and CD40L expression was determined by flow cytometry. sCD40L and IL6 levels were measured by ELISA. In the HC group, we observed a significant increase in serum TC, LDL-C, VLDL-C, TG, sCD40, and IL-6 levels and platelet activation markers compared with levels in the control group. However, t-resveratrol administration to the HC group (HCR group) attenuated the increase in lipids, sCD40, and IL-6 and down-regulated platelet P-selectin, CD40, and CD40L expressions. A positive correlation was found for serum lipids and all the platelet activation markers. Our study showed that the CD40-CD40L dyad is up-regulated in the presence of hypercholesterolemia and that t-resveratrol administration down-regulated the increase.

BACKGROUND

There is an unmet need for a straightforward and cost-effective assessment of multiple lipoprotein risk factors for vascular diseases.

OBJECTIVE

1) To study the relation of various lipoprotein lipid and apolipoprotein (apo) measures on the Friedewald inputs, i.e. plasma triglycerides (TG), cholesterol (TC), and high-density lipoprotein cholesterol (HDL-C). 2) To build up regression models for the appropriate measures based solely on the Friedewald inputs.

METHODS

Data were available for 1,775 plasma samples, from which very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL), and HDL were also isolated by ultracentrifugation. For HDL(2)-C and apolipoproteins, 343 and 247 samples were available, respectively.

RESULTS

Accurate models were obtained for VLDL-TG (cross-validation r=0.98), LDL-C (r=0.91), HDL(2)-C (r=0.92), apoA-I (r=0.92), and apoB (r=0.95). A semi-quantitative model was obtained for IDL-C (r=0.78). Due to the anticipated role of IDL-C in atherosclerosis, it was still kept within the accepted models and pursued further. The associations of the estimates with premature deaths were studied in 4,084 patients with type 1 diabetes. The associations of IDL-C and LDL-C were markedly different, the best predictors of mortality being apoB, apoB to apoA-I ratio, and IDL-C.

CONCLUSIONS

The new models allow identification of clinically relevant lipoprotein profiles with no added cost to the conventional Friedewald formula.

Preeclampsia is one of the most frequent complications of pregnancy, however, little is known about its etiology. The objective of this study was to investigate the association of oxidized low-density lipoprotein (oxLDL) and paraoxonase (PON1) activity in women with either preeclampsia or normotensive (NT) pregnancy. The study groups included 41 pregnant women with preeclampsia and 33 normotensive pregnant women. In all patients maternal serum total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides (TGs) were measured using enzymatic methods. Serum PON1 activities and malondialdehyde (MDA) concentrations were measured by spectrophotometric methods, and oxLDL was measured by enzyme-linked immunoassay (ELISA). Serum concentrations of lipid parameters (TC, LDL, VLDL, and TGs) were significantly higher in preeclampsia compared with NT controls (p < 0.001, p < 0.05, p < 0.05, and p < 0.001, respectively). Serum concentrations of MDA and oxLDL were significantly higher, while PON1 activity was significantly lower in preeclampsia compared with NT controls (p < 0.001, p < 0.001, and p < 0.001, respectively). A positive correlation was detected between oxLDL and MDA (r = 0.876), and a negative correlation was detected between both MDA and oxLDL and PON1 (r = -0.837 and r = -0.759, respectively). Our data demonstrate that preeclampsia is associated with increased oxLDL and decreased PON1 activity. Elevated oxidative stress, oxLDL, dyslipidemia and decreased PON1 activities may cause vascular endothelial damage and contribute to the pathophysiology of preeclampsia.

We propose that Alzheimer's disease (AD) is a single disease with a common metabolic APP-beta A4-amyloid pathway. The multiple genetic and other factors already identified to induce this pathway are reviewed. The molecular genetics of AD has been successfully studied within the last years, and we now can account for the genetic and molecular alterations underlying the majority of familial AD cases inherited with an autosomal dominant pattern of complete penetrance. AD in these pedigrees can be caused by missense mutations within the recently identified PS1 (S182) gene on chromosome 14 (AD3 locus) and the PS2 (STM2/E5-1) gene on chromosome 1, in addition to previously described point mutations of the beta A4-amyloid protein precursor (APP) gene on chromosome 21 (AD1 locus). The majority of AD cases, however, appears to be sporadic or 'familial' in terms of an increased family-associated AD-probability. Genetic risk factors contributing to AD in these cases have also been identified. On chromosome 19, allelic segregation of the APOE gene with both late onset 'familial' (AD2) and sporadic AD has been demonstrated, with the APOE epsilon 4 allele conferring a relatively higher risk of developing AD at an earlier age. Several other risk factors have also been proposed, including the alpha 1-antichymotrypsin allele A (ACT-A), the 5-repeat allele of the VLDL-receptor (VLDL-R) gene, the A2 allele of the HLA-A locus, and possibly yet unknown mitochondrial mutations. All these findings are discussed against the background of what is known about APP metabolism leading to beta A4 amyloid formation, a process that is also modified by APP expression level, alternative splicing of APP exon 15, extracellular signalling and intracellular sorting.

The effect of taurine on hypercholesterolemia induced by feeding a high-cholesterol (HC) diet (10g/kg) to rats was examined. When various amounts of taurine (0.25, 0.5, 1, 2.5, 5, 10, 20, 30, 40 or 50 g/kg diet) were supplemented to HC for 2 wk, serum total cholesterol gradually and significantly decreased in a dose-dependent manner and normalized at the dose of 10 g taurine/kg, compared with the control (cholesterol free) diet group. By contrast, serum HDL-cholesterol was elevated by taurine supplementation. The HC diet caused a significant decrease in the concentration of taurine in serum, liver and heart compared to that in the control group, and the effective dose of supplemental taurine to improve its reduction was 2.5 g/kg diet. In the hypercholesterolemic rats fed the HC diet, the excretion of fecal bile acids and hepatic cholesterol 7 alpha-hydroxylase (CYP7A1) activity and its mRNA level increased significantly, and the supplementation of taurine further enhanced these indexes, indicating an increase in cholesterol degradation. The abundance of mRNA for Apo A-I, one of the main components of HDL, was reduced by HC and recovered by taurine supplementation. Agarose gel electrophoresis revealed that, in hypercholesterolemic rats fed the HC diet, the serum level of the heavier VLDL increased significantly, but taurine repressed this increase and normalized this pattern. Significant correlations were observed between the time- and dose-dependent increases of CYP7A1 gene expression and the decrease of blood cholesterol concentration in rats fed the HC diet supplemented with taurine (time, r = -0.538, P < 0.01, n = 32; dose, r = -0.738, P < 0.001, n = 20). These results suggest that the hypocholesterolemic effects of taurine observed in the hypocholesterolemic rats fed the HC diet were mainly due to the enhancement of cholesterol degradation and the excretion of bile acid.

MicroRNAs are involved in disease development and may be utilized as biomarkers. We investigated the association of blood miRNA levels and a) fatty liver (FL), b) lipoprotein and lipid pathways involved in liver lipid accumulation and c) levels of predicted mRNA targets in general population based cohort. Blood microRNA profiling (TaqMan OpenArray), genome-wide gene expression arrays and nuclear magnetic resonance metabolomics were performed for Young Finns Study participants aged 34-49 years (n = 871). Liver fat status was assessed ultrasonographically. Levels of hsa-miR-122-5p and -885-5p were up-regulated in individuals with FL (fold change (FC) = 1.55, p = 1.36 * 10-14 and FC = 1.25, p = 4.86 * 10-4, respectively). In regression model adjusted with age, sex and BMI, hsa-miR-122-5p and -885-5p predicted FL (OR = 2.07, p = 1.29 * 10-8 and OR = 1.41, p = 0.002, respectively). Together hsa-miR-122-5p and -885-5p slightly improved the detection of FL beyond established risk factors. These miRNAs may be associated with FL formation through the regulation of lipoprotein metabolism as hsa-miR-122-5p levels associated with small VLDL, IDL, and large LDL lipoprotein subclass components, while hsa-miR-885-5p levels associated inversely with XL HDL cholesterol levels. Hsa-miR-885-5p levels correlated inversely with oxysterol-binding protein 2 (OSBPL2) expression (r = -0.143, p = 1.00 * 10-4) and suppressing the expression of this lipid receptor and sterol transporter could link hsa-miR-885-5p with HDL cholesterol levels.

Procarboxypeptidase U (proCPU) is the plasma precursor of carboxypeptidase U (CPU, carboxypeptidase R. plasma carboxypeptidase B or activated thrombin-activatable fibrinolysis inhibitor, TAFIa). CPU removes C-terminal lysine residues that act as plasminogen binding sites from partially degraded fibrin, thereby down-regulating plasminogen activation and fibrinolysis. The present study was carried out as a pilot study to examine whether the plasma proCPU concentration is related to the presence of coronary artery disease (CAD) and/or to levels of established risk indicators for CAD, in a case-control study of 110 men requiring coronary artery bypass grafting (CABG) because of stable angina pectoris. The preoperative plasma proCPU level in the CABG patients was significantly higher than in population-based controls (1029 +/- 154 vs. 974 +/- 140 U/L, p <0.05). In addition, in a subset of the patients (n = 31 ) the proCPU concentration, which was significantly lower on the third postoperative day (-17 +/- 10%), had increased significantly on the sixth day (+14 +/- 12%) after surgery, compared with the preoperative level. In both patients and controls, proCPU concentration was strongly and positively associated with factor VII amidolytic activity and protein C activity, suggesting a common mechanism modulating the plasma levels of these proteins. Otherwise, statistically significant correlations with proCPU were group-specific. In the patients, proCPU correlated significantly with plasma fibrinogen and protein S. In the controls, proCPU correlated significantly with concentrations of cholesterol in plasma. VLDL and LDL. In addition, proCPU correlated significantly with C-reactive protein and haptoglobin levels in the controls only, indicating that also inflammatory mechanisms are involved in the regulation of plasma proCPU. These results suggest that a mechanism exists by which fibrinolytic function is impaired in a manner that is likely to result in more stable fibrin deposits and increase the risk of precocious CAD as well as early occlusion of venous bypass grafts.

The transport and secretion of vitamin E in lipoproteins have been studied in cynomolgus monkeys fed tocopherols labeled with different amounts of deuterium. The animals were fed a single dose of vitamin E containing 60 mumol of each 2R,4'R,8'R-alpha-(5,7-(C2H3)2)tocopheryl acetate (d6-RRR-alpha-tocopheryl acetate; alpha-tocopherol with natural stereochemistry), 2S,4'R,8'R-alpha-5-(C2H3)tocopheryl acetate (d3-SRR-alpha-tocopheryl acetate; alpha-tocopherol with unnatural stereochemistry), and 2R,4'R,8'R-gamma-(3,4-2H)tocopherol (d2-RRR-gamma-tocopherol; gamma-tocopherol with natural stereochemistry). Chylomicrons, as well as the other plasma lipoproteins, contained equal concentrations of all three tocopherols at the earliest time points after feeding suggesting that all three tocopherols were absorbed equally. At later times plasma lipoproteins became preferentially enriched in d6-RRR-alpha-tocopherol. This is likely to be due to hepatic secretion of VLDL (very low density lipoproteins) and other lipoproteins, which were enriched in d6-RRR-alpha-tocopherol, as demonstrated in the lipoproteins isolated from perfused livers that had been obtained 24 h following the administration of the deuterated tocopherols. Taken together these data demonstrate that the liver, not the intestine, is the likely site of discrimination between tocopherol isomers and that the liver secretes nascent lipoproteins preferentially enriched in d6-RRR-alpha-tocopherol.

The net transfer of labeled alpha-tocopherol from donor to acceptor lipoproteins at physiological concentrations was investigated. Labeled lipoproteins were isolated i) following in vitro addition of [3,4-3H] all rac-alpha-tocopherol to plasma, or ii) from plasma obtained 12-16 h after ingestion by normal subjects of an oral dose (100 mg each) of 2R,4'R,8'R-alpha-[5,7-(C2H3)2]tocopheryl acetate and 2S,4'R,'R-alpha-[5-C2H3]tocopheryl acetate. A constant amount (on a protein basis) of labeled lipoprotein was incubated with an increasing amount of unlabeled acceptor lipoprotein for 2 h at 37 degrees C. No discrimination between stereoisomers of alpha-tocopherol was detected. Labeled VLDL and labeled LDL (very low and low density lipoproteins, respectively) tended to retain their labeled tocopherol. Labeled high density lipoproteins (HDL) readily transferred the labeled tocopherol to VLDL >> 60% transferred), while the transfer to LDL was dependent upon the ratio of labeled HDL/LDL with a lower net transfer at higher ratios. This dependency of the distribution of tocopherol upon the ratio of HDL/LDL was also observed in vivo. The tocopherol/mg HDL protein was measured in 11 subjects with varying HDL levels. As the % HDL in the plasma increased from 14 to 50%, the tocopherol/HDL protein also increased (r2 = 0.37, P < 0.05).