[Gestational or essential hypertension in pregnant women limits the capacity to stock triglycerides by the placenta despite raised lipoprotein-lipase activity]

Placenta lipoprotein lipase (LPL) activity as well as serum VLDL and placenta lipids composition were determined in pregnant hypertensive women at term. 46 patients aged from 29 +/- 2 years with gravidic hypertension (HTA-G) and 38 patients with essential hypertension (HTA-E) aged 30 +/- 1 years were compared with 20 normotensive women aged 27 +/- 1 years. Serum triacylglycerols (TG) concentrations were 1.3-fold higher in the both hypertensive patients compared with controls. However, serum phospholipids (PL) and total cholesterol (TC) values were similar in the three groups. VLDL mass and their apolipoproteins, unesterified cholesterol (UC) and cholesteryl esters (CE) contents were significantly increased in hypertensive women compared with controls. In HTA-G and HTA-E patients, respectively. TG-VLDL concentrations were increased by +43% and +36% compared with those of controls (P < 0.01). In placenta, the values were lower 2.2- and 1.9-fold for TG, 2.8 and 2.5-fold for PL and two- and threefold for TC, in HTA-G and HTA-E patients than in controls. Placenta LPL activity was 2.7-fold higher in HTA-G and HTA-E patients compared with that of controls. In conclusion, although placenta LPL activity is higher it is not permit a decrease of serum TG-VLDL on the one hand, and an increase of placenta ability in TG storage on the other hand.

[Fish proteins moderate triacylglycerols, activities of hepatic triacylglycerol lipase and tissue lipoprotein lipases in hypertensive and diabetic rats]

Fish proteins effect compared with casein was determined on triacylglycerols (TG) metabolism and activities of hepatic triacylglycerol lipase (HTGL) and tissue lipoprotein lipases (LPL), in SHR and diabetic SHR. Two groups of rats (n=24) were fed, 2 months, diet containing 20% casein (CAS) or 20% fish proteins (FP). One month before sacrifice, diabetes was induced in one group of rats by a single intraperitoneal injection of streptozotocin (STZ) (60 mg/kg of body weight). FP vs. CAS showed a significant decrease of TG concentrations in plasma (-41%) and liver (-66%), in SHR-STZ. VLDL-LDL mass, which represented the amount of apolipoproteins, TG, phospholipids (PL), unesterified cholesterol (UC), and cholesteryl esters (CE), decreased by 21 and 16% with FP vs. CAS, in SHR and SHR-STZ, respectively, and was concomitant with its low TG. Indeed, TG values was 1.35- and 1.82-fold lower in SHR and SHR-STZ, respectively. In HDL2, a TG diminution of 13% was noted, in SHR with FP vs. CAS. In SHR-STZ with FP, TG and PL were enhanced by 11% and 27%, respectively compared to SHR. HTGL activity decreased by 22% in SHR fed FP compared to those fed CAS. In SHR-STZ with CAS vsSHR, this activity was decreased by 21%. LPL activity in heart was enhanced by 19% in SHR-STZ vs. SHR with FP, when that of muscle was diminished 1.5-fold in SHR with FP vs. CAS and 1.8-fold in SHR-STZ vs. SHR with CAS. Adipose LPL activity was 1.36-fold higher in SHR with FP than CAS. In conclusion, it appears that fish proteins have a hypotriglyceridemic effect, which the mechanism can differ in SHR or SHR-STZ. It may be of interest to propose these fish proteins as lipid metabolism regulator in diseases with hypertriglyceridemia.

Contractility and retrograde flow in lamellipodium motion

We present a phenomenological description of cell locomotion on a solid substrate. The material properties of the actin cytoskeleton in the lamellipodium are described by the constitutive equations of a viscous polar gel with intrinsic activity. The polymerization of the gel takes place in a localized region near the leading edge. Using a simple two-dimensional description, we calculate in the steady state the thickness profile of the lamellipodium which at the rear connects to the cell body; we also calculate the flow profiles and the forces exerted on the substrate. The cell velocity is estimated as a function of externally applied forces. Our description is consistent with experimentally observed properties of motile cells such as the existence of a retrograde flow in the lamellipodium and a dipolar force distribution exerted by the cell on the substrate.

Generic phase diagram of active polar films

We study theoretically the phase diagram of compressible active polar gels such as the actin network of eukaryotic cells. Using generalized hydrodynamics equations, we perform a linear stability analysis of the uniform states in the case of an infinite bidimensional active gel to obtain the dynamic phase diagram of active polar films. We predict, in particular, modulated flowing phases and a macroscopic phase separation at high activity. This qualitatively accounts for experimental observations of various active systems, such as actomyosin gels, microtubules and kinesins in vitro solutions, or swimming bacterial colonies.

N-3 Fatty acids modulate antioxidant status in diabetic rats and their macrosomic offspring

OBJECTIVE

We investigated the role of dietary n-3 polyunsaturated fatty acids (n-3 PUFA) in the modulation of total antioxidant status in streptozotocin (STZ)-induced diabetic rats and their macrosomic offspring.

DESIGN

Female wistar rats, fed on control diet or n-3 PUFA diet, were rendered diabetic by administration of five mild doses of STZ on day 5 and were killed on days 12 and 21 of gestation. The macrosomic (MAC) pups were killed at the age of 60 and 90 days.

MEASUREMENTS

Lipid peroxidation was measured as the concentrations of plasma thiobarbituric acid reactive substances (TBARS), and the total antioxidant status was determined by measuring (i) plasma oxygen radical absorbance capacity (ORAC), (ii) plasma vitamin A, E and C concentrations, and (iii) antioxidant enzymes activities in erythrocytes. The plasma lipid concentrations and fatty acid composition were also determined.

RESULTS

Diabetes increased plasma triglyceride and cholesterol concentrations, whereas macrosomia was associated with enhanced plasma cholesterol and triglyceride levels, which diminished by feeding n-3 PUFA diet. N-3 PUFA diet also reduced increased plasma TBARS and corrected the decreased ORAC values in diabetic rats and their macrosomic offspring. EPAX diet increased the diminished vitamin A levels in diabetic mothers and vitamin C concentrations in macrosomic pups. Also, this diet improved the decreased erythrocyte superoxide dismutase and glutathione peroxidase activities in diabetic and macrosomic animals.

CONCLUSION

Diabetes and macrosomia were associated with altered lipid metabolism, antioxidant enzyme activities and vitamin concentrations. N-3 PUFA diet improved hyperlipidemia and restored antioxidant status in diabetic dams and MAC offspring.

Antioxidant status in alcohol-related diabetes mellitus in Beninese subjects

In the present study, we investigated the antioxidant status in diabetes mellitus, related or not to alcohol consumption. A total of 38 type 1, 48 type 2 and 42 alcohol-related diabetic patients were selected. Total antioxidant status was assessed through the oxygen radical absorbance capacity of the plasma and the determination of enzymatic and non-enzymatic antioxidant molecules. Serum triglycerides, total cholesterol and HDL-cholesterol concentrations were determined and the lipid peroxydation was evaluated by measuring thiobarbituric acid reactive substances (TBARS) assay. Plasma total antioxidant capacity was more decreased in alcohol-related diabetes than that in type 1 and type 2 diabetes, regardless of the complications (retinopathy and renal failure). Plasma vitamin E concentrations were significantly decreased whereas those of vitamin C increased in all of the diabetic patients compared to the controls, irrespective to the complications. In addition, superoxide dismutase and glutathione peroxidase activities were reduced in all the patients (type 1, type 2 and alcohol-related), irrespective to the complications. Glutathione reductase activity was diminished in type 1 and alcohol-related, but not in type 2, diabetic patients. Glutathione (GSH) concentrations significantly decreased in all diabetic patients with a significant decrease in alcohol-related diabetic patients. Excessive alcohol consumption appears as an oxidative aggravating factor in diabetes mellitus. Besides, alcohol-related diabetes highly resembles to type 1 diabetes as far as the antioxidant parameters are concerned.

Carotenoids modulate the trade-off between egg production and resistance to oxidative stress in zebra finches

The allocation of resources to reproduction and survival is a central question of studies of life history evolution. Usually, increased allocation to current reproduction is paid in terms of reduced future reproduction and/or decreased survival. However, the proximal mechanisms underlying the cost of reproduction are poorly understood. Recently, it has been shown that increased susceptibility to oxidative stress might be one of such proximate links between reproduction and self-maintenance. Organisms possess a range of antioxidant defenses, including endogenously produced molecules (e.g., enzymes) and compounds ingested with food (e.g., carotenoids). If reproductive effort increases the production of reactive oxygen species, the availability of antioxidant defenses may partly or fully counteract the free-radical damages. One could, therefore, expect that the trade-off between reproduction and oxidative stress is modulated by the availability of antioxidant defenses. We tested this hypothesis in zebra finches. We manipulated reproductive effort by either allowing or preventing pairs to breed. Within each breeding or non-breeding group, the availability of antioxidant compounds was manipulated by supplementing or not supplementing the drinking water with carotenoids. We found that although birds in the breeding and non-breeding groups did not differ in their resistance to oxidative stress (the breakdown of red blood cells submitted to a controlled free-radical attack), one aspect of breeding effort (i.e., the number of eggs laid by birds in both breeding and non-breeding groups) was negatively correlated with resistance to oxidative stress only in birds that did not benefit from a carotenoid-supplemented diet. This result therefore suggests that carotenoid availability can modulate the trade-off between reproduction and resistance to oxidative stress.

Motor proteins transporting cargos

Processive motor proteins such as kinesin and myosin-V are enzymes that use the energy of ATP hydrolysis to travel along polar cytoskeletal filaments. One of the functions of these proteins is the transport of vesicles and protein complexes that are linked to the light chains of the motors. Modeling the light chain by a linear elastic spring, and using the two-state model for one- and two-headed molecular motors, we study the influence of thermal fluctuations of the cargo on the motion of the motor-cargo complex. We solve numerically the Fokker-Planck equations of motor motion, and find that the mean velocity of the motor-cargo complex decreases monotonously as the spring becomes softer. This effect is due to the random force of thermal fluctuations of the cargo disrupting the operation of the motor. Increasing the size (thus, the friction coefficient) of the cargo also decreases the velocity. Surprisingly, we find that for a given size of the cargo, the velocity has a maximum for a certain friction of the motor. We explain this effect by the interplay between the characteristic length of thermal fluctuations of the cargo on a spring, the motor diffusion length, and the filament period. Our results may be relevant for the interpretation of single-molecule experiments with molecular motors (bead assays), where the motor motion is observed by tracking of a bead attached to the motor.

Changes in lipid metabolism and antioxidant defense status in spontaneously hypertensive rats and Wistar rats fed a diet enriched with fructose and saturated fatty acids

OBJECTIVE

Larger doses of fructose and saturated fat have been associated with oxidative stress and development of hypertension. The effects of modest amounts of fructose and saturated fatty acids on oxidative stress are unknown.

METHODS

To increase knowledge on this question, 10-wk-old spontaneously hypertensive rats and Wistar rats were fed for 8 wk with a control diet or an experimental diet enriched with fructose (18%) and saturated fatty acids (11%; FS diet). The total antioxidant status of organs and red blood cells was assayed by monitoring the rate of free radical-induced red blood cell hemolysis. Sensitivity of very low-density lipoprotein and low-density lipoprotein (VLDL-LDL) to copper-induced lipid peroxidation was determined as the production of thiobarbituric acid-reactive substances. Antioxidant enzymes and vitamins were also measured to establish the oxidative stress effect.

RESULTS

The FS diet did not affect blood pressure in either strain, but it increased plasma insulin concentrations only in Wistar rats without affecting those of glucose of either strain. The FS diet significantly enhanced plasma and VLDL-LDL triacylglycerol concentrations without affecting concentrations of VLDL-LDL thiobarbituric acid-reactive substances. The decreased content of arachidonic acid and total polyunsaturated fatty acids in VLDL-LDL by the FS diet may have prevented lipid peroxidation in this fraction. Moreover, FS consumption by both strains was accompanied by a significant increase in total antioxidant capacity of adipose tissue, muscle, heart, and liver. This may have resulted from increased tissue ascorbic acid levels and glutathione peroxidase and glutathione reductase activities in tissues.

CONCLUSIONS

These findings clearly indicate that the FS diet did not alter blood pressure of spontaneously hypertensive rats and Wistar rats. The FS diet resulted in hypertriglyceridemia but increased the total antioxidant status, which may prevent lipid peroxidation in these rats.

Passive or active fluctuations in membranes containing proteins

We have experimentally investigated the effect of a transmembrane protein, the Ca2+-ATPase, on shape fluctuations of giant vesicles. By using the micropipette method, we have measured a substantial renormalization of the bending modulus due to the presence of proteins in the membrane. Moreover, we have produced the first quantitative measurement of the active force dipole associated with the amplification of the fluctuations when the proteins are activated by adenosine 5'-triphosphate (ATP).

Generic theory of active polar gels: a paradigm for cytoskeletal dynamics

We develop a general theory for active viscoelastic materials made of polar filaments. This theory is motivated by the dynamics of the cytoskeleton. The continuous consumption of a fuel leads to a non equilibrium state characterized by the generation of flows and stresses. Our theory can be applied to experiments in which cytoskeletal patterns are set in motion by active processes such as those which are at work in cells.

An Experimental Test of the Dose‐Dependent Effect of Carotenoids and Immune Activation on Sexual Signals and Antioxidant Activity

Carotenoid-based sexual traits are thought to be reliable indicators of male quality because they might be scarce and therefore might indicate the ability of males to gather high-quality food and because they are involved in important physiological functions (as immune enhancers and antioxidants). We performed an experiment where male and female zebra finches (Taeniopygia guttata) were provided with increasing carotenoid doses in the drinking water during 4 weeks (bill color of this species is a carotenoid-based sexual signal). Simultaneously, birds were split into two groups: one receiving weekly injections of Escherichia coli lipopolysaccharide in order to activate the immune system, the other being injected with the same volume of phosphate buffered saline. We assessed how carotenoid availability and immune activation affected the amount of circulating plasma carotenoids, the beak color, and the antioxidant defenses (assessed as the resistance of red blood cells to a controlled free radical attack). Carotenoid availability affected the amount of circulating carotenoids and beak color; both variables reached a plateau at the highest carotenoid doses. Immune activation diverted carotenoids from plasma, and this in turn affected the expression of the sexual trait. Finally, we found a positive correlation between the change in circulating carotenoids and antioxidant defenses. These results support the idea that carotenoids have important physiological properties that ensure the honesty of carotenoid-based sexual traits.

Fluid membranes exchanging material with external reservoirs

We investigate the dynamics of a single component fluid bilayer, which exchanges material with the surrounding fluid. We derive covariant equations of motion taking into account solvent permeation, exchange of lipids between solvent and the membrane and discuss the sources of noise in these equations. Different lipid concentrations on both sides of the membrane lead to a non-equilibrium state. We discuss steady states as well as shape instabilities which occur at a critical osmotic-pressure difference.

[Effect of fish protein on blood pressure, glycemia and plasma and urinary parameters in spontaneously hypertensive rats (SHR) and diabetic SHR]

Fish protein (FP) effect compared to casein (CAS) was studied on blood pressure (BP) evolution and glycemia in part, and on plasma lipid, angiotensine II and aldosterone concentrations and urinary aldosterone on the other hand, in SHR and in SHR with streptozotocin-induced diabetes (SHR-STZ). Two groups of rats (6 SHR and 6 SHR-STZ) were fed for 2 months diet containing 20% CAS or 20% FP. One month before sacrifice, diabetes was induced into one group of rats by a single intraperitonealy injection of streptozotocin (STZ). The results showed that FP diminished blood pressure (-9%) in SHR, compared with CAS. In contrast, FP enhanced significantly blood pressure in SHR-STZ vs SHR (p<0.01). There was no effect on glycemia with fish protein. FP compared to CAS involved a diminution (-41%) and (-17%) of total cholesterol and (-26%) and (-9%) of phospholipids in SHR and SHR-STZ, respectively. Moreover, a decrease of triacylglycerols (-21%) was noted in SHR-STZ with FP vs CAS. In SHR, plasma aldosterone and angiotensine II concentrations were reduced (-62%) and (-64%) and urinary aldosterone amounts were enhanced with FP compared to CAS (p<0.05). In SHR-STZ group, aldosterone value was fivefold lower in plasma and twofold higher in urine with FP compared to CAS. A significant enhancement of urinary aldosterone was noted in SHR-STZ vs SHR whatever diet-consumed. In conclusion, FP has a beneficial effect on blood pressure by modulating the hypertension markers i.e. plasma total cholesterol, angiotensine II and aldosterone, in SHR group, and on total cholesterol and triglycerids in SHR-STZ. FP reduces plasma aldosterone by its enhanced urinary excretion. It is necessary to specify the action mode of FP in order to propose it as nutritional complement in the degenerative diseases such as hypertension and diabetes.

Changes in serum lipoprotein lipids and their fatty acid compositions and lipid peroxidation in growing rats fed soybean protein versus casein with or without cholesterol

OBJECTIVE

We compared the effects of diets based on soybean protein and casein supplemented or not supplemented with 0.1% cholesterol on plasma lipoprotein lipid amounts and their fatty acid compositions, lecithin:cholesterol acyl-transferase activity, and lipid peroxidation.

METHODS

The composition and concentration of lipid and apolipoprotein in different lipoprotein classes, plasma LCAT activity, and lipid peroxidation were determined in rats fed 20% highly purified soybean protein or casein with or without 0.1% cholesterol for 2 mo.

RESULTS

Soybean protein and casein diets with or without cholesterol had similar plasma total cholesterol concentrations. Soybean protein consumption diminished very low-density lipoprotein particle number, as measured by diminished contents of very low-density lipoprotein triacylglycerol, phospholipid, and apolipoprotein-B100. Lecithin:cholesterol acyl-transferase activity was not significantly modified by either protein. The soybean protein diet decreased the linoleate desaturation index (20:4[omega-6]/18:2[omega-6]) in liver and high-density lipoprotein fraction 2-3-phospholipids but enhanced red blood cell resistance against free radical attack. Addition of cholesterol to both protein diets decreased concentrations of high-density lipoprotein fraction 2-3 cholesterol. Lecithin:cholesterol acyl-transferase activity tended to be greater after cholesterol feeding, likely due to the enhanced high-density lipoprotein fraction 2-3 apolipoprotein-AI, a cofactor activator for lecithin:cholesterol acyl-transferase. Regardless of dietary protein source, cholesterol supplementation decreased the linoleate desaturation index in liver and plasma lipoprotein lipids and red blood cell resistance to free radical attack.

CONCLUSIONS

Our results suggest that the dietary protein origin affects lipid peroxidation and polyunsaturated fatty acid biosynthesis and distribution among liver and different lipoprotein lipid classes, but plays only a minor role in the regulation of plasma and lipoprotein cholesterol concentrations. Providing dietary cholesterol (0.1%) with casein or soybean protein attenuates the effects of these proteins, with the exception of plasma cholesterol.

Membranes with rotating motors: microvortex assemblies

We study collections of rotatory motors confined to 2-dimensional manifolds. The rotational motion induces a repulsive hydrodynamic interaction between motors leading to a non-trivial collective behavior. For high rotation speed, motors should arrange on a triangular lattice exhibiting crystalline order. At low speed, they form a disordered phase where diffusion is enhanced by velocity fluctuations. In confining geometries and under suitable boundary conditions, motor-generated flow might enhance left-right symmetry-breaking transport. All these effects should be experimentally observable for motors driven by external fields and for dipolar biological motors embedded into lipid membranes in a viscoelastic solvent.

Fish protein improves blood pressure but alters HDL2 and HDL3 composition and tissue lipoprotein lipase activities in spontaneously hypertensive rats

The two-month effects of dietary fish protein and casein on VLDL, HDL(2) and HDL(3) compositions and hepatic lipase (HTGL) and tissue lipoprotein lipase (LPL) activities were examined in spontaneously hypertensive rats (SHR) at 4 wk of age. After 2 mo of experiment, the fish protein diet induced lower blood pressure (-14 %) as compared to casein. Liver triacylglycerol and total cholesterol concentrations were 1.37- and 1.71-fold lower in the fish protein group than in the casein group, respectively. Total cholesterol concentration in plasma was also diminished by fish protein (-21 %) and was reflected in HDL(2) fraction (-44 %). SHR fed the fish protein diet as compared with those fed casein, showed a significantly low HDL(3) particle number, as measured by diminished HDL(3) mass and apo A-I. The consumption of fish protein did not affect VLDL particle number, but significantly decreased VLDL-triacylglycerol (-32 %) and adipose tissue total lipid concentrations as compared to casein. This was accompanied by diminished HTGL and adipose tissue LPL activities (-10%, -91%, respectively). These data demonstrate that fish protein plays an antihypertensive role and reduces plasma and tissue lipid concentrations. Thus, a fish protein intake might be beneficial for patients with hypertension.

Refined contour analysis of giant unilamellar vesicles

The fluctuation spectrum of giant unilamellar vesicles is measured using a high-resolution contour detection technique. An analysis at higher q vectors than previously achievable is now possible due to technical improvements of the experimental setup and of the detection algorithm. The global fluctuation spectrum is directly fitted to deduce the membrane tension and the bending modulus of lipid membranes. Moreover, we show that the planar analysis of fluctuations is valid for spherical objects, even at low wave vectors. Corrections due to the integration time of the video camera and to the section of a 3D object by the observation plane are introduced. A precise calculation of the error bars has been done in order to provide reliable error estimate. Eventually, using this technique, we have measured bending moduli for EPC, SOPC and SOPC: CHOL membranes confirming previously published values. An interesting application of this technique can be the measurement of the fluctuation spectra for non-equilibrium membranes, such as "active membranes".

Role of tensile stress in actin gels and a symmetry-breaking instability

It has been observed experimentally that the actin gel grown from spherical beads coated with polymerization enzymes spontaneously breaks the symmetry of its spherical shape, and yields a "comet" pushing the bead forward. We propose a mechano-chemical coupling mechanism for the initialization of this symmetry breaking. Key assumptions are that the dissociation of the gel takes place mostly in the region of the external surface, and that the rates of the dissociation depend on the tensile stress in the gel. We analyze a simplified two-dimensional model with a circular substrate. Our analysis shows that the symmetric steady state is always unstable against the inhomogeneous modulation of the thickness of the gel layer, for any radius of the circular substrate. We argue that this model represents the essential feature of three-dimensional systems for a certain range of characteristic lengths of the modulation. The characteristic time of the symmetry-breaking process in our model depends linearly on the radius of curvature of the substrate surface, which is consistent with experimental results, using spherical latex beads as substrate. Our analysis of the symmetry-breaking phenomenon demonstrates aspects of mechano-chemical couplings that should be working in vivo as well as in vitro.

Asters, vortices, and rotating spirals in active gels of polar filaments

We develop a general theory for active viscoelastic materials made of polar filaments. This theory is motivated by the dynamics of the cytoskeleton. The continuous consumption of a fuel generates a nonequilibrium state characterized by the generation of flows and stresses. Our theory applies to any polar system with internal energy consumption such as active chemical gels and cytoskeletal networks which are set in motion by active processes at work in cells.

VLDL metabolism in rats is affected by the concentration and source of dietary protein

The present study was designed to determine if changes in dietary protein level and source are related to changes in VLDL lipid concentrations and VLDL binding by hepatic membranes and isolated hepatocytes. Male Wistar rats were fed cholesterol-free diets containing 10, 20 or 30 g/100 g casein or highly purified soybean protein for 4 wk. Hepatic, plasma and VLDL lipids, VLDL apo B-100 and VLDL uptake by isolated hepatocytes and VLDL binding to hepatic membrane were determined. Increasing casein or soybean protein level (from 10 to 30 g/100 g) in the diet increased VLDL apo B-100, indicating an increase in the number of VLDL particles. VLDL uptake by isolated hepatocytes and VLDL binding to hepatic membrane increased when the protein level increased from 10 to 20 g/100 g in the diet and decreased with 30 g/100 g protein, regardless of protein type. The dietary protein source did not affect plasma total cholesterol concentrations at any protein level. Feeding 20 g/100 g soybean protein compared with casein lowered plasma triglyceride concentrations and VLDL number as measured by decreased VLDL-protein, -phospholipid, -triglyceride, -cholesterol and -apo B-100. VLDL uptake by isolated hepatocytes and VLDL binding to hepatic membrane were higher in rats fed soybean protein than those fed casein. The higher VLDL uptake could be responsible for the hypotriglyceridemia in rats fed soybean protein.

Plasma lipoprotein lipase, hepatic lipase activities, VLDL, LDL compositions at different times of hemodialysis

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).