In order to study the degree and pathogenic aspects of the secondary hyperlipoproteinemia in patients under diuretic therapy we measured serum lipids, lipoproteins and the apoproteins A1, A2 and B in 12 adults after a 4 weeks placebo period and 6 weeks of treatment with chlorthalidon. There was a significant increase in atherogenic low density lipoproteins (LDL), (18%, P less than 0.05) whereas the high density lipoprotein-cholesterol Apo A1 and A2 levels were not significantly altered. The same was true for the total serum triglyceride- and the very low density lipoprotein- and LDL-triglyceride levels. The activity of lipoprotein lipase and hepatic triglyceride lipase was slightly but not significantly increased. A delayed LDL-catabolism seems to be the most probable pathogenic mechanism underlying the Chlorthalidon-induced hyperlipoproteinemia.

We studied 162 mother-neonate pairs to determine the relationship between w3 long chain polyunsaturated fatty acid (w3LCP) intake during pregnancy and their levels in the mother and the neonate, and the general lipid pattern in the mother and the neonate. A dietetic interview was performed to assess the w3LCP intake during pregnancy. In both mothers and neonates we studied the w3LCPs in plasma and erythrocyte phospholipids and also the general lipid profile (total cholesterol, HDL-c, LDL-c, triglycerides, apo A1 and apo B). The w3LCP intake assessed by the dietetic interview (0.74 +/- 0.52 g/day) did not correlated with any of the parameters of the general lipid pattern in mothers or neonates. In mothers, the w3LCP levels in plasma expressed in percentages showed a positive correlation with apo A1 and HDL-c, and a negative correlation with triglycerides and apo B. The w3LCPs levels in mothers showed an inconsistent and weak correlation with triglycerides and apo B in neonates. When w3LCPs levels were assessed in the neonates themselves a consistent positive correlation was found with triglycerides. We concluded that in the dietetic range of our population, the intake of w3LCPs was not associated to any changes in the general lipid pattern of mothers or neonates. Whereas the w3LCP levels in mothers were correlated with the changes in the general lipid pattern reported outside pregnancy, such correlations were not present in regard to the neonate general profile, whereas the newborn's w3LCP levels were correlated with triglycerides. We believe that the hypertriglyceridemia of pregnancy, the placenta and the peculiarities of fetal metabolism are the causes of the aforementioned findings.

BACKGROUND

Chylomicrons carry in the bloodstream dietary fats absorbed the intestine for storage in the body tissues such as adipose and muscle. The two-step chylomicron metabolism consists in lipolysis by lipoprotein lipase on vessel walls and hepatic uptake of triglyceride-depleted remnants. Chylomicron metabolism is understudied in cancer, despite its direct involvement in the patient nutritional status. We investigated this metabolism in Hodgkin and non-Hodgkin lymphoma patients, using the method of triglyceride-rich emulsions that mimic chylomicrons.

METHODS

The chylomicron-like emulsion, labeled with [9,10-3H]glycerol-trioleate and [1-14C] cholesteryl-oleate was intravenously injected into 11 Hodgkin's, 19 non-Hodgkin's patients and 12 healthy subjects. Triglyceride kinetics evaluate lipolysis whereas cholesteryl ester kinetics evaluate remnant removal.

RESULTS

Plasma total, LDL, HDL cholesterol, apo B, apo A1 and Lp(a) values were similar between the three groups, but VLDL cholesterol and triglycerides were higher in the lymphoma groups. The fractional catabolic rate (FCR, in min(-1)) of the emulsion triglycerides was roughly three-fold smaller in non-Hodgkin's (0.043+/-0.007, mean+/-S.E.M., P<0.001) and Hodgkin's (0.045+/-0.009, P<0.0001) lymphoma patients compared with the control values (0.151+/-0.032). FCR of the emulsion cholesteryl esters, was four-fold smaller in non-Hodgkin's (0.016+/-0.002, P<0.0001), and three-fold in Hodgkin's lymphoma patients (0.024+/-0.006, P<0.001) compared with the control group (0.069+/-0.013). The lipolysis index, calculated from the decay curves of both isotopes was also markedly smaller in both groups of lymphoma patients compared with the controls.

CONCLUSIONS

In both lymphoma groups, marked alterations in chylomicron lipolysis and remnant removal occurs.

The levels of total cholesterol, triglyceride, LDL-C, HDL-C, apolipoprotein A1 and apolipoprotein B in the serum were measured in a selected series of 100 CAD patients (77 men and 23 women) who underwent coronary angiography and 141 non-CAD controls. Mean values of those variables differed significantly between the CAD and non-CAD groups matched in age, body weight, hypertension and smoking. There are significant difference in apolipoproteins A1, B and the ratio of apolipoprotein B to A1 between angina and myocardial infarction groups. Using stratified and multivariate stepwise regression analysis, it was shown that the apo A1, apoB/apoA1 are more sensitive and specific than the ordinary indices (e.g. total cholesterol, triglycerides, LDL-C and HDL-C) in estimating the degree of coronary artery stenosis and the differentiation of CAD from other diseases.

To further characterize the spectrum of potentially atherogenic disturbances in lipoprotein composition in non-insulin-dependent diabetes mellitus (NIDDM), we have studied a subset of women with NIDDM before and after treatment with the lipophilic lipid-lowering drug probucol (1 gm day), which we have shown corrects certain compositional abnormalities these women share with subjects who have hypercholesterolemia. Before treatment, the NIDDM group had a somewhat higher plasma triglyceride level (154 +/- 58.3 mg/dl, vs control, 80.0 +/- 21 mg/dl [mean +/- SD]; p less than 0.025) than controls but their cholesterol and high-density lipoprotein cholesterol (HDL-C) levels did not differ from control levels. A number of significant disturbances, however, were present in the surface and core lipid composition of their lipoproteins. Although the cholesterol content of NIDDM low-density lipoprotein (LDL) was similar to that of controls, its content of sphingomyelin and phosphatidylinositol plus phosphatidylserine and sphingomyelin-to-lecithin ratio all were significantly reduced. Moreover, their very-low-density lipoprotein (VLDL) and HDL2 tended to have reduced amounts of free (unesterified) cholesterol (FC) relative to lecithin, and their HDL2 and HDL3 tended to be triglyceride enriched. Probucol therapy resulted in significant decreases in total plasma cholesterol (-15%), FC (-28%), HDL-C (-22%), and triglyceride (-16%) and in apoproteins A-I, B, and E (apo A-I, B, and E), without changing diabetic control (before probucol: hemoglobin A1, cholesterol, 10.7% +/- 2.7%; after probucol: 10.9% +/- 3.0%).(ABSTRACT TRUNCATED AT 250 WORDS)

Hyperlipidaemia of 18 male and 20 female patients following successful renal transplantation was treated with daily 20 mg fluvastatin (Lescol) for 12 weeks. The patients were several months after transplantation, and their total cholesterol levels exceeded 6.5 mmol/l following an 8-week diet. The effect of fluvastatin on the levels of total cholesterol, HDL, LDL, triglyceride, Apo A1 and Apo B, as well as of lipoprotein(a) was examined. Furthermore, changes of the renal function (GFR-urea, creatinine, uric acid) and hepatic function (bilirubin, GOT, GPT, CPK, ALP) were followed up, together with the body weight and blood pressure. The results of the examinations are summarized as follows: Fluvastatin may be administered effectively and without side effects in a daily dose of 20 mg in appropriately selected renal transplant patients. The average total cholesterol values, which were 7.91 mmol/l in men and 7.78 mmol/l in women following the diet, were reduced by 22-25% (p < 0.001) after 6 and 12 weeks, respectively, of fluvastatin treatment. The levels of LDL also decreased significantly (p < 0.001): in response to a 20 mg evening dosage, reduction of more than 25% was observed in 78% of men and 65% of women. Reductions of the Apo B levels were more pronounced in the females (18.3% men vs. 21.2% women). The ratio C/HDL-C decreased both in men (from 5.49 to 4.19) and in women (from 4.83 to 4.02). The ratio Apo B/Apo A1 also decreased (men: from 0.86 to 0.73, women: from 0.73 to 0.66). The concentrations of HDL and Apo A1 did not increase significantly, the reductions in the levels of triglyceride and lipoprotein(a) were not considerable either. An increase in the levels of hepatic enzymes and CPK was not encountered during the administration of fluvastatin. In two patients the levels of serum bilirubin increased by 2-4 micromol/l. Three patients complained about temporary myalgias of the sacroiliac or lumbar region which, however, were not accompanied by elevated CPK levels. The monitored levels of cyclosporine, urea and creatinine did not increase significantly during the 12 weeks of treatment. Two patients had temporary gastric complaints.

We describe the lipoprotein and apolipoprotein profiles and their relationship to cardiovascular risk factors in Australian Aboriginal children. This cross-sectional study within a longitudinal birth cohort study involved Australian Aboriginal children born between 1987 and 1990 and re-examined between 1998 and 2001. Height, weight, blood pressure, waist circumference, body fat percentage, cholesterol, triglycerides, HDL-c, LDL-c, apolipoprotein B and A1 were measured. Mean age was 11.4 years (52% male). Mean cholesterol, triglyceride, HDL-c and LDL-c did not differ from reference data. Measures of obesity, blood pressure and prevalence of the metabolic syndrome did not differ in those children with lipoproteins in the upper quartile of the cohort (lower quartile for HDL-c). Boys with an Apo-B/A1 ratio in the upper quartile of the cohort had higher BMI z-score, waist z-score, % body fat, diastolic blood pressure and frequency of the metabolic syndrome (p<0.05). In girls, waist circumference, % body fat and the prevalence of the metabolic syndrome was higher in those with an Apo-B/A1 ratio in the upper quartile (p<0.05).The Apo-B/A1 ratio may be useful to identify cardiovascular risk in Australian Aboriginal children and is suited to clinical practice as the assays are standardised, accurate, automated and a fasting sample is not required.

BACKGROUND

Lipoatrophic diabetes is characterized by the near absence of adipose tissue and the presence of insulin-resistant diabetes. Fasting hypertriglyceridaemia and increased postprandial lipidaemia are also present, but the metabolism of chylomicrons, the triglyceride-rich lipoproteins in the circulation that carry the dietary fats absorbed by the intestine, was not specifically investigated. Because both the activity of insulin-dependent lipoprotein lipase that catalyses the chylomicron lipolysis and the storage of the lipolysis products are affected in the disease, it is important to evaluate how those changes may ultimately affect the chylomicron lipolysis and removal of chylomicron remnants from the circulation.

OBJECTIVE

The aim of the study was to evaluate the chylomicron intravascular metabolism in patients with lipoatrophic diabetes.

METHODS

Six patients with lipoatrophic diabetes (four females, two males) aged 22.2 +/- 4.4 years, with body mass index (BMI) 21.6 +/- 3.6 kg/m(2), were compared with 12 healthy control subjects (seven females, five males) aged 24.3 +/- 2.1 years with BMI 22.5 +/- 2.7 kg/m(2).

METHODS

The plasma kinetics of intravenously injected chylomicron-like emulsions labelled with (3)H-triglycerides ((3)H-TG) and with (14)C-cholesteryl esters ((14)C-CE) were determined, the former tracing the chylomicron lipolysis by lipoprotein lipase and the latter the removal of chylomicron remnants from the plasma.

RESULTS

Triglyceride values (8.3 +/- 9.2 mmol/l) in the patients were higher (P < 0.005) and high density lipoprotein (HDL) cholesterol values (0.8 +/- 0.2 mmol/l) lower (P < 0.0005) than in controls (0.7 +/- 0.2 and 1.3 +/- 0.4 mmol/l, respectively) whereas total cholesterol, apoprotein B (apo B) and apo A1 were similar. The fractional clearance rate (FCR, in min(-1)) of (3)H-TG was 0.014 +/- 0.016 and the FCR of (14)C-CE was 0.008 +/- 0.012 in the patients and 0.046 +/- 0.024 and 0.024 +/- 0.012 in the controls, respectively (P < 0.05). Thus FCRs of both emulsion labels were markedly reduced in the patients, indicating that lipolysis and remnant removal were diminished. Diminished remnant removal may be due to either deficient lipolysis or deficient removal mechanisms.

CONCLUSIONS

The metabolism of chylomicrons tested by the emulsion method is impaired in lipoatrophic diabetes.

This study was designed to investigate whether serum lipoprotein (a) is affected by pregnancy and to relate this to changes in other lipids, lipoproteins and apolipoproteins. The study involved twenty-nine healthy Caucasian pregnant women at term and 27 non-pregnant women matched for age who acted as controls. Samples of venous blood were obtained from 29 pregnant women at term (between 37 and 42 weeks) and 22 of these women provided a second sample after 12 weeks post-partum. Twenty-seven non-pregnant women acted as controls. Samples were taken for Lp(a) and also cholesterol, triglyceride, HDL-cholesterol, apolipoprotein (apo) A and B1. No significant difference was found in the serum concentrations of Lp(a). However, the pregnant women had significantly higher serum concentrations of cholesterol, triglyceride, apo A1 and B (P<0.001) than the controls. The ratio of apo A1: apo B was significantly lower than controls (P<0.001). HDL-cholesterol was not altered by pregnancy but was lower (P<0.05) than the controls after a period of 12 weeks post-partum. Despite a hyperlipidaemia in pregnancy the serum concentrations of Lp(a) are not affected suggesting different metabolic control for this lipoprotein.

Blood levels of triglycerides, total cholesterol, isolated lipoprotein fractions (VLDL-LDL- and HDL-cholesterol) and apoproteins (Apo-A1 and Apo-B) were examined in multi-infarct dementia, senile dementia of the Alzheimer type, ischemic stroke associated with carotid atherosclerosis and in control subjects. Forty patients divided into 10 consecutive patients for each group were studied. Alzheimer patients showed mean total cholesterol and Apo-B values significantly higher than control subjects. Apo-B was significantly higher in stroke patients than in controls. The mean lowest HDL-cholesterol (HDL-c) value was observed in stroke patients. No significant differences in mean HDL-c levels were found between patients with multi-infarct and Alzheimer dementia.

Lipid abnormalities are major risk factors for premature coronary artery disease (CAD). However, the type and prevalence of dyslipidemia in these patients have not been well characterised, especially in some ethnic groups. The purpose of the present work was to determine the lipid disorders in patients of Northwestern Greece with premature CAD. The study population comprised of 132 men and 38 women who underwent elective diagnostic arteriography in our University Hospital. Subjects with>> or = 1 lesion that narrowed the lumen of any of the 15 coronary artery segments by>> or = 70% were considered to be CAD cases (n=108), whereas those with narrowing < 70% were excluded (n=54). Asymptomatic subjects (n=104) matched for age and sex were taken as controls. Compared with the controls, patients with premature CAD had increased serum levels of total cholesterol, LDL cholesterol, triglycerides, Apo B, and Lp(a), and decreased serum levels of HDL cholesterol and Apo A1. A lipoprotein or apolipoprotein abnormality was identified in 89 CAD patients (82.4%). The increased serum Apo B level >> 130 mg/dl) was the most common lipid abnormality observed in 72 patients. However, the most prevalent dyslipidemic phenotypes in our patients were type IIA followed by hypoalpha and hyperApoB. Compared to the control population, CAD patients had increased incidence of IIA and hypoalpha phenotypes. On the contrary, a normal lipoprotein phenotype was more common in the control population compared to CAD patients (56.7% vs. 17.6%, P<0.001). We conclude that the majority of Greek patients with premature CAD exhibit lipid and lipoprotein abnormalities, which to a large extent can be defined by determining the traditional lipid parameters (total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides). However, in some cases the value of the quantification of other lipid parameters such as apolipoproteins and Lp(a) should be taken into account.

OBJECTIVE

Glucose intolerance is frequently associated with an altered plasma lipid profile and increased cardiovascular disease risk. Nonetheless, lipid metabolism is scarcely studied in normolipidemic glucose-intolerant patients. The aim of this study was to investigate whether important lipid metabolic parameters, such as the kinetics of LDL free and esterified cholesterol and the transfer of lipids to HDL, are altered in glucose-intolerant patients with normal plasma lipids.

METHODS

Fourteen glucose-intolerant patients and 15 control patients were studied; none of the patients had cardiovascular disease manifestations, and they were paired for age, sex, race and co-morbidities. A nanoemulsion resembling a LDL lipid composition (LDE) labeled with 14C-cholesteryl ester and ³H-free cholesterol was intravenously injected, and blood samples were collected over a 24-h period to determine the fractional clearance rate of the labels by compartmental analysis. The transfer of free and esterified cholesterol, triglycerides and phospholipids from the LDE to HDL was measured by the incubation of the LDE with plasma and radioactivity counting of the supernatant after chemical precipitation of non-HDL fractions.

RESULTS

The levels of LDL, non-HDL and HDL cholesterol, triglycerides, apo A1 and apo B were equal in both groups. The 14C-esterified cholesterol fractional clearance rate was not different between glucose-intolerant and control patients, but the ³H-free-cholesterol fractional clearance rate was greater in glucose-intolerant patients than in control patients. The lipid transfer to HDL was equal in both groups.

CONCLUSIONS

In these glucose-intolerant patients with normal plasma lipids, a faster removal of LDE free cholesterol was the only lipid metabolic alteration detected in our study. This finding suggests that the dissociation of free cholesterol from lipoprotein particles occurs in normolipidemic glucose intolerance and may participate in atherogenic signaling.

Comparative Gene Identification-58 (CGI-58), as an adipose triglyceride lipase (ATGL) activator, strongly in- creases ATGL-mediated triglyceride (TG) catabolism. Previous studies have shown that CGI-58 affects intestinal cholesterol homeostasis independently of ATGL activity. Therefore, we hypothesized that CGI-58 was involved in macrophage cholesterol metabolism and consequently atherosclerotic lesion formation. Here, we generated macrophage-specific CGI-58 transgenic mice (Mac-CGI-58 Tg) using an SRA promoter, which was further mated with ApoE-/- mice to create litters of CGI-58 Tg/ApoE-/- mice. These CGI-58 Tg/ApoE-/- mice exhibited an anti-atherosclerosis phenotype compared with wild type (WT) controls (CGI-58 WT/ApoE-/-), illustrated by less plaque area in aortic roots. Moreover, macrophage-specific CGI-58 overexpression in mice resulted in upregulated levels of plasma total cholesterol and HDL-cholesterol. Consequently, higher expression levels of PPARa, PPARγ, LXRα, ABCA1, and ABCG1 were detected in macrophages from CGI-58 Tg/ApoE-/- mice compared to CGI-58 WT/ApoE-/- counterparts, which were accompanied by elevated macrophage cholesterol efflux toward HDL and Apo A1. Nevertheless, serum levels of TNF-α and IL-6 were reduced by macrophage-specific CGI-58 overexpression. Finally, bone marrow (BM) transplantation experiments further revealed that ApoE-/- mice reconstituted with Mac-CGI-58 Tg BM cells (ApoE-/-Tg-BM chimera) displayed a significant reduction of atherosclerosis lesions compared with control mice reconstituted with Mac-CGI-58 WT BM cells (ApoE-/-/WT-BM chimera). Collectively, these data strongly suggest that CGI-58 overexpression in macrophages may protect against atherosclerosis development in mice.

The lipoprotein components were studied in connection with a population study concerning the state of health and living habits of the elderly people in Turku, Finland. Serum levels of total cholesterol, high density lipoprotein (HDL) cholesterol, triglycerides, apolipoprotein A1 (apo A1) and apolipoprotein B (apo B) of the 347 elderly people (aged 65 years or over) were measured and those of low density lipoprotein (LDL) cholesterol were calculated. The levels of total cholesterol, LDL cholesterol and apo B were significantly higher in females than in males, and the concentrations decreased with advancing age. The concentrations of HDL cholesterol and apo A1 were significantly higher in females than in males but age had no effect. Serum triglycerides behaved differently in males and females; in females age had a significant increasing effect whereas in males no age effect was observed. The apo A1/apo B ratio did not differ between males and females. Reference values of serum lipids, lipoproteins and apolipoproteins of the elderly are suggested.

Cibacron Blue F3GA was covalently attached onto monosize poly(glycidyl methacrylate) [poly(GMA)] beads for removal of human serum albumin (HSA) from human serum. Monosize poly(GMA) beads, 1.6 microm in diameter, were produced by dispersion polymerization. Cibacron Blue F3GA loading was 1.73 mol/g. HSA adsorption experiments were performed by stirred-batch adsorption. The non-specific adsorption of HSA was low (0.8 mg/g polymer). Dye attachment onto the monosize beads significantly increased the HSA adsorption (189.8 mg/g). The maximum HSA adsorption was observed at pH 5.0. With an increase of the aqueous phase concentration of sodium chloride, the adsorption capacity decreased drastically. The equilibrium adsorption of HSA significantly decreased with increasing temperature. The elution studies were performed by adding 0.1 M Tris/HCl buffer containing 0.5 M NaSCN to the HSA solutions in which adsorption equilibria had been reached. The elution results demonstrated that the adsorption of HSA to the adsorbent was reversible. The depletion efficiencies for HSA were above 87% for all studied concentrations. To test the efficiency of HSA removal from human serum, proteins in the serum and eluted portion were analyzed by two-dimensional gel electrophoresis. Eluted proteins include mainly albumin, and a small number of nonalbumin proteins such as apo-lipoprotein A1, sero-transferrin, haptoglobulin and alpha1-antitrypsin were bound by the dye-affinity beads. IgA was not identified in eluted fraction.

The present study aimed to investigate the clinical characteristics and 1-year outcomes of acute myocardial infarction (AMI) patients without significant stenosis on a coronary angiogram comparison with the clinical characteristics and outcomes of patients with significant coronary artery stenosis. A total of 1,220 patients with AMI were retrospectively classified into Group I (≥50% diameter stenosis, n=1,120) and Group II (<50%, n=100). Group II was further divided into two subgroups according to the underlying etiology: cryptogenic (Group II-a, n=54) and those with possible causative factors (Group II-b, n=46). Patients in Group II were younger, were more likely to be women, and were less likely to smoke and to have diabetes mellitus than were patients in Group I. The levels of cardiac enzymes, LDL-cholesterol levels, and the apo-B/A1 ratio were lower in Group II. However, 1-month and 12-month rates of major adverse cardiac events (MACE) were not significantly different between the two groups. The Group II-b subgroup comprised 29 patients with vasospasm, 11 with myocardial bridge, and 6 with spontaneous thrombolysis. Left ventricular ejection fraction and creatinine clearance were lower and levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hs-CRP) were higher in Group II-a than in Group II-b. However, outcomes including MACE and mortality at 12 months were not significantly different between the two subgroups. The 1-year outcomes of patients in Group II were similar to those of patients in Group I. The clinical outcomes in Group II-a were also similar to those of Group II-b, although the former group showed higher levels of NT-proBNP and hs-CRP.

OBJECTIVE

To assess classical and non-classical metabolic risk biomarkers in prepubertal children with different levels of cardiorespiratory fitness (CRF).

METHODS

CRF was assessed by the 20 m shuttle run test. To estimate physical activity, participants were observed while engaged in an after-school programme. Additionally, a short test based on a validated questionnaire was used to obtain information about physical activity practice and sedentary habits. Anthropometric parameters, blood pressure, and classical and non-traditional metabolic risk biomarkers--plasma lipid profile, glucose and insulin, homeostasis model assessment-insulin resistance index (HOMA-IR), plasma uric acid, transaminases and C-reactive protein (CRP)--were measured.

METHODS

The study was conducted in local elementary schools in Córdoba, Spain.

METHODS

One hundred and forty-one healthy children (eighty-eight boys, fifty-three girls) aged 7-12 years, in Tanner stage I, were recruited. They were divided into two groups after they performed the 20 m shuttle run test: equal or higher cardiovascular fitness (EHCF) group and low cardiovascular fitness (LCF) group.

RESULTS

The LCF group displayed significantly higher TAG (P = 0.004) and lower HDL cholesterol levels (P = 0.001), as well as significantly lower values for the non-traditional lipid marker apo-A1 (P = 0.001) compared with the EHCF group. The LCF children displayed higher plasma glucose (P = 0.003) and insulin levels, higher HOMA-IR scores (P < 0.001) and higher plasma uric acid and CRP levels (P < 0.05). After adjustment for BMI, age and sex, no statistically significant differences were found between groups for the biomarkers analysed.

CONCLUSIONS

The study provides new information to understand the role not only of weight status but also of the level of CRF on the metabolic health profile of prepubertal children.

OBJECTIVE

Oral contraceptive formulations can alter plasma lipid and lipoprotein levels; however, lower-dose triphasic tablets show only minimal metabolic effects during 6 or 12 cycles of use. Involvement of lipids in chronic cardiovascular conditions, plus long-term use of oral contraceptive tablets, prompted this first 24-cycle study of the effect of triphasic formulations on young women.

METHODS

69 women assigned randomly to an ethinyl estradiol/levonorgestrel formulation (Triphasil) or an ethinyl estradiol/norethindrone formulation (Ortho 7/7/7) and 25 control women (no hormonal contraception) had blood sampled for lipids and lipoproteins pre-trial, and at 3- or 6-cycle intervals for 24 cycles.

RESULTS

At cycle 24, control women experienced no significant change from baseline in any variable except apolipoprotein B (apo B). Plasma apo B increased 42% (P < .01), reflecting the LDL apo B increase (42%, P < .01). Both combination formulations significantly increased apo B (plasma, VLDL, IDL and LDL); the increases ranged between 47% and 84%. Plasma apo A1 rose (15%, P < .001) in the Ortho 7/7/7 group only. Plasma and LDL triglycerides were increased significantly (P < .001) by the norethindrone product, 43% and 81%, respectively, and plasma and LDL cholesterol, 14% and 28%, respectively. Cholesterol decreased in all other subfractions, including HDL (11%, P < .01). HDL cholesterol decreased significantly in the Triphasil group (8%, P < .05); no other cholesterol subfractions changed significantly. All cycle-24 lipid and lipoprotein values remained well within respective normal ranges.

CONCLUSIONS

Although 2-year exposure to the triphasic oral contraceptive formulations changed the lipid risk factors for cardiovascular disease only within normal ranges, there remains potential for long-term health effects when compounded with other risk factors.

We have sought the structural basis for the differing substrate specificities of human glutathione transferase P1-1 (class Pi) and human glutathione transferase A1-1 (class Alpha) by adding an extra helix (helix 9), found in the electrophilic substrate-binding site (H-site) of the human class Alpha enzyme, at the C terminus of the human class Pi enzyme. This class Pi-chimera (CODA) was expressed in Escherichia coli, purified and characterized by kinetic and crystallographic approaches. The presence of the newly engineered tail in the H-site of the human Pi enzyme alters its catalytic properties towards those exhibited by the human Alpha enzyme, as assessed using cumene hydroperoxide (diagnostic for class Alpha enzymes) and ethacrynic acid (diagnostic for class Pi) as co-substrates. There is a change of substrate selectivity in the latter case, as the k(cat)/K(m)(EA) value decreases about 70-fold, compared to that of class Pi. With 1-chloro-2,4-dinitrobenzene as co-substrate there is a loss of catalytic activity to about 2% with respect to that of the Pi enzyme. Crystallographic and kinetic studies of the class Pi-chimera provide important clues to explain these altered catalytic properties. The new helix forms many complimentary interactions with the rest of the protein and re-models the original electrophilic substrate-binding site towards one that is more enclosed, albeit flexible. Of particular note are the interactions between Glu205 of the new tail and the catalytic residues, Tyr7 and Tyr108, and the thiol moiety of glutathione (GSH). These interactions may provide an explanation of the more than one unit increase in the pK(a) value of the GSH thiolate and affect both the turnover number and GSH binding, using 1-chloro-2,4-dinitrobenzene as co-substrate. The data presented are consistent with the engineered tail adopting a highly mobile or disordered state in the apo form of the enzyme.

BACKGROUND

The efflux of cellular cholesterol mediated by apolipoprotein (apo)A-I and ATP-binding cassette transporter A1 (ABCA1) is a major pathway of reverse cholesterol transport. We investigated the effect of aspirin on this process.

METHODS

The expression levels of ABCA1 in RAW264.7 cells were determined using reverse transcription polymerase chain reaction and Western blot analysis. ³H-cholesterol efflux was measured by scintillation counting.

RESULTS

0.5 mmol/l aspirin increased apoA-I-mediated cholesterol efflux and increased the expression of ABCA1. By increasing the dose of aspirin higher than 0.5 mmol/l, ABCA1 expression and function were significantly decreased. In cells transfected with a specific peroxisome proliferator-activated receptor (PPAR)-α small interfering RNA, the induction of ABCA1 expression and apoA-I-mediated ³H-cholesterol efflux by aspirin were substantially suppressed.

CONCLUSIONS

The data demonstrate that low-dose aspirin increases ABCA1 expression via a PPAR-α-dependent mechanism and increases apoA-I-mediated cholesterol efflux.

1. The objective of this study was to compare in cultured human hepatocytes or Hep G2 cells, changes in the fate of unesterified low density lipoprotein (LDL)-cholesterol induced by crilvastatin, a new cholesterol lowering drug and a reference statin, simvastatin. 2. The experiments were carried out for 20 h, each well contained 4.2 x 10(5)/cm2 Hep G2 cells or 0.5 x 10(5)/Cm2 human hepatocytes, 130 microM ursodeoxycholate, 0.68 microCi or 1.59 microCi unesterified human [14C]-LDL-cholesterol, crilvastatin or simvastatin at 0 or 50 microM (both cell types) or 300 microM (Hep-G2 cells). Incubation with the two drugs resulted in increased amounts of unesterified [14C]-LDL-cholesterol taken by the two cell types, compared to control. 3. Crilvastatin 50 microM led to significantly higher quantities of [14C]-glyco-tauro-conjugated bile salts, compared to simvastatin. Statins reduced the apo B100 level secreted by the two cell types (simvastatin) or human hepatocytes (crilvastatin). Crilvastatin enhanced both the level of apo A1 secreted by the Hep G2 cells and the level of APF, a high density lipoprotein (HDL) and biliary apoprotein. 4. Crilvastatin not only acts by stimulating LDL-cholesterol uptake by hepatocytes, but also by enhancing the catabolism of LDL-cholesterol in bile salts and probably by stimulating HDL and/or bile component secretion. Such a mechanism was not previously described for HMG CoA reductase inhibitors. Our results on APF show that this apoprotein could be considered also as an indicator of changes in bile and/or HDL compartments. 5. The human hepatocyte model appeared to be a suitable and relevant model in the pharmacological-metabolic experiments carried out in this study. It led to more consistent data than those obtained with Hep G2 cells.

In this work we aimed to identify the differentially expressed proteins and their potential roles during peri-implantation period through proteomics-based approach. Adult healthy female mice were mated naturally with fertile males to produce pregnancy. The models of pseudopregnancy, delayed implantation, and artificial decidualization were established. The protein profile between pre-implantation (D1) and implantation (D5) period was compared by two-dimensional electrophoresis (2-DE) and identified by mass spectrometry (MS). 2-DE yielded comparative images presenting over 500 protein spots in D1 and D5 mouse endometrium. 15 proteins were identified, of which stathmin 1, Apo-A1, hnRNP H3, transgelin 2 and arginase 1 were validated by western blotting. Stathmin 1 expression did not change in pseudopregnancy, but activation of implantation, or induction of decidualization increased it dramatically. Under non-pregnant status, progesterone alone or in combination with17β-estradiol increased it dramatically. Our results clarified the protein profile in mouse endometrium during implantation. The specific expression profile of stathmin 1 suggested that it should be involved in implantation and serve as a potential regulator of this process. These findings may contribute to the better understanding of the molecules events during embryo implantation, and subsequently improve the ability to treat infertility.

OBJECTIVE

To examine the acute effects of estradiol-17beta (E(2)) and progesterone (P) on serum levels of insulin, lipids and lipoproteins in estrogen-deficient postmenopausal women, whereby, a direct cause-effect relationship could be established without the influence of lifestyle changes.

METHODS

Nine postmenopausal women were given oral E(2) (Estrace) 2 mg/day for 28 days and oral micronized P (Prometrium) 200 mg/day in the last 14 days of E(2) treatment. Fasting blood samples were obtained before starting E(2) (day 1) and P (day 15) and on day 29. Serum levels of insulin, triglycerides (TG), total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL) and lipoprotein (a) (Lp(a)) at the three time points were compared by Friedman analysis of variance (ANOVA). Corresponding levels of glucose, the apolipoproteins (Apo) A1 and B and serum androgen levels were also evaluated.

RESULTS

E(2) decreased while P increased fasting levels of insulin (32.45+/-3.57, 26.36+/-2.90 and 37.36+/-3.67 pmol/l on day 1, 15 and 29 respectively; P<0.01). Fasting glucose to insulin ratios changed inversely (P<0.01). E(2) increased HDL from 1.07+/-0.05 mmol/l on day 1 to 1.17+/-0.07 mmol/l on day 29 but decreased corresponding levels of Lp(a) from 261+/-93 to 211+/-83 U/l (P=0.03 for both). TC and LDL levels fell significantly after 14 days of E(2) treatment with no further decrease when P was added. Androgen levels remained unchanged during hormone treatment.

CONCLUSIONS

The sequential, acute effects of E(2) and micronized P on insulin and lipids confirm a direct cause-effect relationship. The acute effects of P on insulin in particular, highlights the importance of standardizing the medication days according to estrogen and progestin in the clinical evaluation of their true metabolic impact in longer-term studies and may influence the choice of progestin type, dose and duration in hormone replacement.

The purpose of the present study was to investigate the relationships of change in high density lipoprotein cholesterol (HDL-C) with changes in sex hormone binding globulin (SHBG), physical fitness and spontaneous dietary intake before and after endurance training. Ten pre-menopausal obese women (32 to 49 years) who had never smoked or regularly drunk alcohol participated in this study. Physical training at an intensity of lactate threshold was performed for six months at a frequency of three times per week for 60 minutes using a cycle ergometer. Together with a reduction in body weight (-4.1 kg; P < 0.05) and with increases in maximal oxygen uptake (VO2max = +3.4 ml/kg/min or +0.09 l/min; P < 0.05), the training induced some changes in both plasma lipid and lipoprotein. Although the total cholesterol (total-C), triglyceride, HDL2-C and apoprotein A1 (Apo A1) levels did not change, significant increases in HDL-C and HDL3-C, and significant reductions in Apo B, total-C/HDL-C ratio and fasting insulin concentrations were found after training. SHBG levels tended to increase after endurance training, but the changes were not significant. No alteration was observed in spontaneous dietary intake after training. A significant correlation (r = 0.648) was observed between the change in VO2 max(l/min) and the change in SHBG. In addition, changes in both VO2 max(l/min) and SHBG were significantly associated with changes in HDL-C, HDL2-C and Apo A1. The changes in dietary intake did not correlate with the changes in SHBG, VO2max, HDL-C, HDL2-C and Apo A1.(ABSTRACT TRUNCATED AT 250 WORDS)