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PubMed1998

Lack of effect of leptin on glucose transport, lipoprotein lipase, and insulin action in adipose and muscle cells.

The effect of leptin on glucose transport, lipogenesis, and lipoprotein lipase activity was studied in cultured rat adipocytes and 3T3-L1 adipocytes. Leptin had no effect on basal and insulin stimulated glucose transport in isolated adipocytes from the rat and the genetically obese mouse. The incorporation of glucose into lipids was also unaffected. Lipoprotein lipase (LPL) activity remained unchanged in response to leptin in these cells, as well as in minced adipose tissue. Leptin also had no effect on both basal and insulin-stimulated glucose transport in cultured rat and human skeletal muscle cells. These studies showed that leptin had no effect on glucose transport, lipoprotein lipase activity, and insulin action in fat and muscle cells in vitro.

3T3 Cells↗
PubMed2001

Physical activity modulates the combined effect of a common variant of the lipoprotein lipase gene and smoking on serum triglyceride levels and high-density lipoprotein cholesterol in men.

Physical activity has been identified as a protective factor against the occurrence and progression of coronary heart disease. The lipoprotein lipase (LPL) HindIII polymorphism has been associated with changes in triglyceride and high density lipoprotein (HDL)-cholesterol levels. We have investigated whether the association between the LPL HindIII genetic polymorphism and lipid levels is modified by physical activity. We have also tested the hypothesis that physical activity may interact with smoking and the LPL HindIII polymorphism to determine an individual's plasma lipid concentrations. A total of 520 men were selected from a representative sample used in a population study conducted in Gerona, Spain. The median value (291 kcal/day) of energy expenditure in leisure-time physical activity of the studied sample was selected as a cut-off to define sedentary or active subjects. Serum HDL-cholesterol was positively and significantly associated with the amount of daily energy expenditure in physical activity, whereas inverse associations were seen between physical activity and triglyceride concentration and with the triglyceride to HDL-cholesterol ratio. These effects were consistent across LPL HindIII genotypes. There was a statistically significant interaction between LPL genotype and smoking on lipid concentrations. No statistically significant differences were observed in lipid levels of active or sedentary non-smokers between H- carriers and H+H+ homozygotes for the LPL HindIII polymorphism. In smokers, sedentary H+H+ homozygotes showed significantly higher triglyceride and lower HDL-cholesterol concentrations than sedentary H- carriers. These differences were smaller and not statistically significant when lipid values of active H+H+ homozygotes were compared with active H- carriers. Among all subgroups, sedentary smokers with the H+H+ genotype had the most adverse lipid profile, which was considerably less adverse in H+H+ smokers who were physically active. These findings suggest that the presence of the H+H+ genotype has a deleterious effect on lipid profile in an adverse environment such as smoking, and that the expenditure of more than 291 kcal/day in physical activity attenuates this effect.

Cholesterol, HDL↗
PubMed1998

Secretory phospholipase A2 and lipoprotein lipase enhance 15-lipoxygenase-induced enzymic and nonenzymic lipid peroxidation in low-density lipoproteins.

The oxidation of low-density lipoprotein (LDL) is thought to contribute to atherogenesis. 15-Lipoxygenase (15LO) induces LDL oxidation, and phospholipase A2 enhances this process [Sparrow, C. P. , Parthasarathy, S., and Steinberg, D. (1988) J. LipidRes. 29, 745-753]. As the underlying mechanism of the enhancing effect has not been investigated previously, we here show that in the presence of soybean 15LO (SLO) or human 15LO (rhLO), the addition of lipoprotein lipase, porcine pancreatic, or human type IIa secretory phospholipase A2 (sPLA2) greatly enhanced the accumulation of hydro(pero)xides of all major classes of LDL's lipids. Hydroperoxides of free fatty acids accumulated exclusively as enzymic products with kinetics reflecting both the formation of free fatty acids and the initial 'build-up' of alpha-tocopheroxyl radical. In contrast, hydroperoxides of cholesteryl esters and phosphatidylcholine accumulated linearly over comparatively longer periods of time and, in the case of rhLO, well beyond inactivation of the oxygenase. With SLO, formation of oxidized esterified lipids occurred nonenzymically, independent of the presence of lipase and despite the oxygenase remaining active until the end of the incubation. Enhancement of rhLO-induced LDL lipid peroxidation by sPLA2 was eliminated by a neutralizing anti-sPLA2 antibody, indicating that lipolytic activity was required for this effect. LDL depleted of alpha-tocopherol was resistant to oxidation by 15LO alone, whereas lipase overcame this resistance, demonstrating that lipases enhance 15LO-induced enzymic and nonenzymic peroxidation of LDL lipids. This is likely due to provision of free fatty acid substrate, resulting in an enhanced rate of free radical formation which itself causes nonenzymic peroxidation of esterified lipids. As lipases and 15LO are present in atherosclerotic lesions, our findings could be of pathophysiological significance.

Animals↗
PubMed1977

Identification of an adipose tissue-like lipoprotein lipase in perfusates of chicken liver.

The nature of the lipolytic activity released from chicken livers perfused with Krebs-Ringer buffer (pH 7.0) containing heparin (50 or 10 U/ml), fraction V albumin (3%), and glycerol (20%) was investigated. The nonrecirculating perfusates contained both previously described NaCl-resistant "liver lipase" as well as an apoLp-Gluactivated lipoprotein lipase (LPL). Crude perfusate lipolytic activity was separated on heparin-Sepharose columns into two enzymatic peaks which were eluted at mean NaCl molarities of 0.75 M (liver lipase) and 1.2 M (LPL). The liver LPL activity was stimulated 7-fold by human apoLp-Glu (half maximal activity at 1.5 microgram/ml) and inhibited by apoLp-Ala, apoLp-Ser, apoLp-GlnI, and apoLP-GlnII. Liver LPL was fully inhibited by anti-adipose LPL immunoglobulins. The "liver lipase" was not affected by apoLp-Glu (3-34 microgram/ml) or anti-adipose LPL immunoglobulins. The data demonstrate the presence in liver perfusates of a LPL with properties similar to adipose tissue lipoprotein lipase.

Adipose Tissue↗
PubMed2003

Common variants in the lipoprotein lipase gene in Brazil: association with lipids and angiographically assessed coronary atherosclerosis.

Lipoprotein lipase is the rate-limiting enzyme in the lipolysis of plasma triglyceride-rich lipoproteins. We studied six variants (T-93G, D9N, N291S, PvuII, HindIII and S447X) in the lipoprotein lipase (LPL) gene in 309 non-diabetic patients with angiographically assessed coronary artery disease and in 197 controls in a southern Brazilian population of European descent. The HindIII H-allele was associated with lower triglycerides (p < 0.01) and higher high-density lipoprotein cholesterol (p = 0.03) levels, and the S447X mutation was associated with lower triglyceride levels (p < 0.01) in males, but not females. No other significant lipid associations were observed. Haplotypes were derived from these two sites (HindIII/S447X), and carriers of H-S and H-X haplotypes showed lower triglycerides (p < 0.01) and increased high-density lipoprotein cholesterol (p = 0.01) levels when compared to the H+S haplotype in males. In this gender, the H-X haplotype was associated with a protective effect (OR = 0.36, 95%CI = 0.13-0.97) for significant disease (> or = 60% of luminal coronary stenosis), even controlling for other classical risk factors.

Aged↗
PubMed1977

Lipoprotein lipase in cultured heart cells: characteristics and cellular location.

Lipase activity extracted from cultured neonatal rat heart cells was characterized and identified as lipoprotein lipase. Enzyme activity was stimulated by human apoC-II and rat serum; serum stimulation was prevented by human apoC-I and by apoC-II. Lipolysis was maximal at pH 8.0 and was inhibited by protamine sulfate, NaCl, and high concentrations of heparin. About 50% of heart cell lipase activity applied to heparin-Sepharose bound to the gel and was eluted with a NaCl gradient. A peak of lipase activity was observed at 0.84 M NaCl. Neonatal rat heart cells in culture are a mixture of muscle and non-muscle cells. To determine the cellular location of the lipoprotein lipase, enzyme activity and muscle cell content of the cultures were determined. Myosin ATPase was used as an index of muscle cell content since ATPase specific activity correlated (r = +0.97) with muscle cell content determined immunofluorescently. When muscle cell content of cultures was decreased or increased by differential plating, lipase specific activity was constant. Moreover, lipase specific activity was constant during culture growth despite a decrease in muscle cell content. It was concluded that lipoprotein lipase activity of cultured heart cells is not associated solely with either muscle or non-muslce cells.

Adenosine Triphosphatases↗
PubMed1983

The effects of pH and salt on the lipid binding and enzyme activity of lipoprotein lipase.

This paper demonstrates a striking difference between the effects of salt and pH on the activity of lipoprotein lipase against two different substrates: Intralipid and bovine milk fat droplets. With the former substrate 1 M NaCl caused only a slight reduction in enzyme activity and the stimulation by apolipoprotein C-II was the same from 0.1 to 1.1 M NaCl. In contrast, 0.5 M or more NaCl virtually abolished the enzyme activity in the milk system. In this system the salt also abolished binding of the enzyme to the lipid droplets, whereas in the Intralipid system most of the enzyme remained bound even at 1 M NaCl. A similar picture was obtained with respect to effects of pH. In the milk system the activity decreased sharply at pH values above 8.5, whereas in the Intralipid system it continues to rise to pH 10, and the stimulation by activator protein is the same at all pH values. Correlating with this, the binding of the enzyme to the lipid droplets was highly dependent on pH values in the milk systems, with optimum binding around pH 8, whereas in the Intralipid system most of the enzyme remained bound to the lipid droplets at all pH values. These studies demonstrate that apolipoprotein C-II can activate lipoprotein lipase at a wide range of salt concentrations and of pH. They suggest that the well-known effects of high salt concentrations and of high pH to decrease lipoprotein lipase activity are exerted primarily on the enzyme itself.

Animals↗
PubMedDate not supplied

Lipoprotein lipase in experimental diabetic rats: beneficial effect of vanadate treatment.

Elevated values of circulating triglycerides were observed in streptozotocin-hyperglycemic rat while cholesterol concentrations did not differ from controls. Daily oral administration of sodium metavanadate to these diabetic animals normalized blood glucose values without raising the reduced levels of insulin. Concomitant with the normalization of the glycemia, the elevated triglyceride values found in diabetic rats were also corrected. Lipoprotein lipase activity in adipose and cardiac tissues was significantly decreased in the streptozotocin-diabetic animals. Similarly, the hepatic lipase activity was also depressed. After vanadate treatment, lipoprotein lipase as well as hepatic lipase activities were corrected towards normal values. Thus, vanadate treatment of streptozotocin-diabetic animals induces normalization of blood glucose and triglycerides levels, while maintaining low amounts of circulating insulin. It also restores the depressed activities of adipose and cardiac lipoprotein lipase and hepatic lipase.

Adipose Tissue↗
PubMed2006

Association of lipoprotein lipase Hind III and Ser 447 Ter polymorphisms with dyslipidemia in Asian Indians.

Studies have shown an association between the lipoprotein lipase gene and dyslipidemia and atherosclerosis in some populations. The aim of this study was to investigate the association between the common lipoprotein lipase HindIII (T-G) and Ser447Ter (C-G) polymorphisms with dyslipidemia in Asian Indians, who are known to have very high rates of premature coronary artery disease. A total of 1,015 subjects, comprising 550 normal glucose-tolerant subjects and 465 patients with type 2 diabetes, were randomly selected from the Chennai Urban Rural Epidemiology Study. The total serum cholesterol, high-density lipoprotein (HDL) cholesterol, and serum triglyceride levels were assayed using enzymatic methods. Low-density lipoprotein cholesterol was calculated using the Friedewald formula. Genotyping was done using the polymerase chain reaction-restriction fragment length polymorphism method. A significant association was found between the H+ allele of HindIII with low HDL cholesterol and elevated triglyceride levels. The Ser allele of Ser447Ter was also strongly associated with low HDL cholesterol levels. No association was found between the H+ allele and Ser Allele with the total or low-density lipoprotein cholesterol levels. Group-wise haplotype frequencies were generated using the expectation-maximization algorithm to detect differences in overall haplotype frequency profiles between the case-control groups. The haplotype analysis showed that the H+ Ser and H- Ter were the "high-risk" and "low-risk" haplotypes for low HDL cholesterol and elevated triglyceride levels, respectively. In conclusion, the H+ Ser haplotype of the lipoprotein lipase gene was associated with low HDL cholesterol levels and hypertriglyceridemia in Asian Indians.

Asian People↗
PubMed1999

Endogenously produced lipoprotein lipase enhances the binding and cell association of native, mildly oxidized and moderately oxidized low-density lipoprotein in mouse peritoneal macrophages.

It has been well established that purified lipoprotein lipase (LPL) can facilitate the cellular uptake of various native and modified lipoproteins when added exogenously to macrophages. Because activated macrophages express LPL endogenously, it was the aim of this study to investigate the effect of macrophage-produced LPL on the uptake of native low-density lipoprotein (LDL) and LDL that has been modified to various degrees by Cu(2+)-mediated oxidation. Cell binding and uptake of Eu(3+)-labelled native and oxidized LDL was determined in mouse peritoneal macrophages (MPM) from normal mice and induced mutant mice that lack LPL expression in MPM. We found that LPL expressed by MPM was able to increase cell binding and association of native LDL (by 121% and 101% respectively), mildly oxidized LDL (by 47% and 43%) and moderately oxidized LDL (by 30% and 22%). With increased levels of lipoprotein oxidation, the relative proportion of LPL-mediated LDL uptake decreased. This decrease was not due to weakened binding of LPL to oxidized LDL. The drastically increased uptake of highly oxidized LDL in MPM by scavenger-receptor-mediated pathways might dominate the simultaneous exogenous or endogenous LPL-mediated uptake of this lipoprotein. Competition experiments with positively charged poly(amino acids) furthermore suggested that histidine, arginine and lysine residues in LPL are important for the interaction between LDL and LPL. Our results imply that physiological levels of LPL produced by macrophages facilitate the uptake of native LDL as well as mildly and moderately oxidized LDL. This process might, in the micro-environment of arteries, contribute to the accumulation of macrophage lipids and the formation of foam cells.

Amino Acids↗
PubMed1994

Tissue- and gender-specific modulation of lipoprotein lipase in intact and gonadectomised rats treated with dl-fenfluramine.

This study evaluated the respective and interactive effects of chronic dl-fenfluramine treatment, an anorectic serotoninergic agonist, and gonadectomy on lipoprotein lipase activity in adipose tissue and skeletal muscle. Male and female Sprague-Dawley rats were gonadectomised. These as well as intact animals were treated with dl-fenfluramine or a placebo for 28 days. Gonadectomy brought about an increase in final body weight of females (16-18%, P < 0.0001), but a decrease in that of male animals (9-13%, P < 0.001). These changes were proportional to those of food intake. The increase in body weight of gonadectomised female rats was paralleled by that of retroperitoneal adipose tissue and vastus lateralis muscle weights, whereas in male rats, gonadectomy diminished muscle weight only. Lipoprotein lipase activity was doubled (P < 0.0001) by gonadectomy in adipose tissue of female rats, but remained unaltered by the surgery in male animals. Enzyme activity in muscle was unaffected by gonadectomy in both genders. Treatment with dl-fenfluramine reduced weight gain in males and females, whether they had been gonadectomised or not. A concomitant reduction was observed in adipose tissue mass and lipoprotein lipase activity, which was reduced to 50-65% of the activity measured in placebo-treated animals (P < 0.01). The drug remained without effect on muscle weight and lipoprotein lipase activity in either gender. Thus removal of gonadal steroids had divergent effects on LPL activity with regard to gender and tissue. In addition, dl-fenfluramine treatment was followed by decreased enzyme activity in adipose tissue, but not in muscle, this pattern being independent of the nature or presence of gonadal steroids.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1989

Effects of weight loss and weight maintenance on the serum lipids, lipoprotein lipase and hepatic triglyceride lipase activities in obese rats.

The effects of obesity, weight loss and weight maintenance on the serum lipid levels and lipoprotein lipase and hepatic triglyceride lipase were investigated in rats. Obesity induced by high-fat (HF) feeding was associated with decreased serum triglyceride levels (HF: 70.3 +/- 8.2, control (CON): 140.0 +/- 26.9 mg/dl, P less than 0.05), increased lipoprotein lipase (LPL, HF: 593.2 +/- 10.6 vs CON: 280 +/- 19.5 nmol FFA/min per mg tissue, P less than 0.05) and suppressed hepatic triglyceride lipase activities (HTGL, HF: 14.2 +/- 0.5 vs CON: 18.0 +/- 0.4 nmol FFA/min per mg tissue, P less than 0.01). After a weight loss to the level of control rats, weight maintenance was achieved either by high-protein (HP) or chow feedings (CH). Both high-protein (HFHP) and chow (HFHC) groups had similar weights but only high-protein feeding restored the normal body compositions. Both groups of rats had higher total (TC, HFHP: 146 +/- 10.7; HFCH: 104.8 +/- 5.1 mg/dl), and high density lipoprotein cholesterol levels (HDL-C, HFHP: 100.8 +/- 15.6; HFCH: 75.5 +/- 5.5 mg/dl) and lower lipoprotein lipase (HFHP: 238.2 +/- 15.8, HFCH: 354.8 +/- 34.9 nmol FFA/min per mg tissue) and hepatic triglyceride activities (HFHP: 16.3 +/- 1.1; HFCH: 14.5 +/- 0.6 nmol FFA/min per mg tissue) than control rats (TC: 70.1 +/- 4.7 mg/dl; HDL-C: 14.2 +/- 4.3 mg/dl; LPL: 742.4 +/- 82.3 nmol FFA/min per mg tissue; HTGL: 20.5 +/- 1.0 nmol FFA/min per mg tissue, P less than 0.05 to 0.005) or the rats who regained weight by resuming high-fat feeding (TC: 59.5 +/- 6.7 mg/dl; HDL-C: 10.2 +/- 6.7 mg/dl; LPL: 1284.3 +/- 90 nmol FFA/min per mg tissue; HTGL: 22.2 +/- 1.9 nmol FFA/min per mg tissue, P less than 0.05 to 0.005). The high protein-group had significantly higher total and high-density-lipoprotein cholesterol levels than the chow fed animals despite comparable body weights in both groups. The findings of this study suggest that weight maintenance induced by high protein feeding is more successful in restoring the normal body composition. However, high protein feeding is also associated with high serum cholesterol levels. The clinical applications of these findings need to be evaluated further.

Animals↗
PubMed1979

Guinea pig very low density lipoproteins are a good substrate for lipoprotein lipase.

In contrast to plasma from most other animals, guinea pig plasma causes little or no stimulation of lipoprotein lipase activity. Very low density lipoproteins (VLDL) isolated by ultracentrifugation of guinea pig serum caused a definite stimulation of lipase activity, whereas the infranatant inhibited the activity. Gel filtration in 5 M guanidinium hydrochloride of delipidated VLDL demonstrated that the activation was caused by a low molecular weight protein. The VLDL themselves were hydrolized at similar rates as human VLDL both by guinea pig and by bovine lipoprotein lipases. Thus, guinea pig VLDL contain an activator for lipoprotein lipase analogous to that in other animals and there is enough of the activator to support rapid hydrolysis of the VLDL lipids by the lipase.

Animals↗
PubMed1979

Increase in lipoprotein lipase during clofibrate treatment of hypertriglyceridemia in patients on hemodialysis.

In 11 hypertriglyceridemic patients on hemodialysis, clofibrate (1 to 1.50 g per week) reduced plasma triglyceride (-40 +/- 20%, P less than 0.001), very-low-density-lipoprotein triglyceride (-44 +/- 20%, P less than 0.001) and very-low-density lipoprotein cholesterol (-39 +/- 25%, P less than 0.01), and it increased high-density-lipoprotein cholesterol (82 +/- 106%, P less than 0.005). Low pretreatment lipoprotein-lipase activity in adipose-tissue specimens and postheparin plasma increased to normal with clofibrate, whereas low hepatic triglyceride lipase activity did not change. The reduced very-low-density-lipoprotein triglyceride correlated with the increased lipoprotein-lipase activity in adipose tissue (rs = 0.792, P less than 0.02, n = 8) and postheparin plasma (rs = 0.851, P less than 0.02, n = 8), whereas increased high-density-lipoprotein cholesterol correlated with changes in this activity in adipose tissue (rs = 0.696, P less than 0.06) and post-heparin plasma (rs = 0.679, P less than 0.10). There was no correlation between changes in hepatic triglyceride lipase activity and plasma lipids during treatment. Reduced lipoprotein-lipase activity may cause hypertriglyceridemia and decreased high-density-lipoprotein cholesterol in patients on hemodialysis; clofibrate may correct these abnormalities by increasing lipoprotein-lipase activity to normal.

Adipose Tissue↗
PubMed1990

Acylglycerol reactivity and reaction mechanism of bovine milk lipoprotein lipase.

The sequential lipolysis of trioleoylglycerol and the triacylglycerols of very-low-density lipoprotein by bovine milk lipoprotein lipase can be described by the consecutive reactions: (formula: see text) where k'1, k'2 and k'3 are apparent first-order rate constants. The values of these rate constants dictate several conclusions concerning the reaction mechanism of this enzyme. The significant differences in the k'1, k'2 and k'3 values for trioleoylglycerol substrate imply that cleavage of the acyl-enzyme intermediate is not the rate-limiting step of the overall lipolysis reaction. This conclusion is further supported by the lack of an effect of hydroxylamine on the reaction rate. In addition, the observed isotope effect of k1 (H2O): k1(D2O) of 1.32 with trioleoylglycerol substrate suggests that the acyl-enzyme formation may contribute to the rate-limiting step of the lipoprotein-lipase-catalyzed reaction. In the presence of excess bovine serum albumin, the transfer of fatty acid product from the enzyme to albumin must be fast, since the k'1 values are not dependent on albumin concentration. When albumin is not in excess, the reaction is retarded and the study of reaction kinetics demonstrates negligible reaction after the available albumin is saturated.

Animals↗
PubMed2004

Lipoprotein lipase gene polymorphism and lipid profile in coronary artery disease.

CONTEXT: Lipoprotein lipase (LPL) plays a central role in lipid metabolism, hydrolyzing triglyceride in chylomicrons and very-low-density lipoproteins. The PvuII polymorphic variant of LPL gene is common and might affect risk of coronary artery disease (CAD). OBJECTIVE: Our aim was to determine whether LPL- PvuII polymorphism can be considered to be an independent risk factor or a predictor for CAD in Turkish subjects. DESIGN: We used polymerase chain reaction and restriction enzyme digestion to determine the distribution of the previously described C-->T transition that causes a PvuII polymorphism in intron 6 among healthy blood donors of Turkish origin and among angiographically confirmed CAD patients with comparable ethnic backgrounds. RESULTS: For the PvuII genotypes, within the CAD group (n = 80), the +/- genotype was found in 39 individuals (48.8%), whereas 25 (31.3%) carried the +/+ genotype, and 14 (17.5%) carried the -/- genotype. Within the control group (n = 49), the -/- genotype was found in 19 individuals (38.8%), 16 (32.7%) carried the +/- genotype, and 14 (28.6%) carried the +/+ genotype. The genotype frequency distribution was significantly different (P =.049) in the CAD and control study groups. The most frequent genotype among CAD patients was +/-; this genotype was more frequent in patients than in control subjects. However, the -/- genotype was more prevalent in the control group. Lipoprotein lipase-PvuII polymorphism was found to be associated with fasting total cholesterol and low-density lipoprotein cholesterol levels. The +/+ genotype was found to have higher levels of total cholesterol and low-density lipoprotein cholesterol in both the CAD and control groups. CONCLUSION: There was a difference in the distribution of LPL-PvuII genotypes between the healthy subjects and the patients with CAD. Lipoprotein lipase-PvuII polymorphisms were not detected as independent risk factors for CAD in this study group, but had associations with lipid levels.

Amino Acid Substitution↗
PubMed1994

Reduced adipose tissue lipoprotein lipase responses, postprandial lipemia, and low high-density lipoprotein-2 subspecies levels in older athletes with silent myocardial ischemia.

Healthy older (64 +/- 1 years, mean +/- SEM) athletic (maximal oxygen consumption [VO2max] > 40 mL/kg/min) normocholesterolemic men with no prior history of coronary artery disease (CAD) were recruited for cardiovascular and metabolic studies. Thirty-three percent had asymptomatic exercise-induced ST segment depression on their exercise electrocardiogram (ECG), consistent with silent myocardial ischemia (SI). We hypothesized that abnormalities in high-density lipoprotein (HDL) and postprandial triglyceride (TG) metabolism may increase their risk for CAD. Compared with 12 nonischemic controls of comparable age, percent body fat, and VO2max, the 13 men with SI had decreased fasting HDL cholesterol ([HDL-C] 41 +/- 2 v 50 +/- 2 mg/dL, P < .001) and %HDL2b subspecies levels as measured by gradient gel electrophoresis (22 +/- 2 v 34 +/- 3, P < .001). Fasting plasma TG and low-density lipoprotein cholesterol (LDL-C) levels were the same in both groups. Although plasma glucose levels during an oral glucose tolerance test (OGTT) were similar in both groups, the total insulin area was higher in men with SI (P < .05). After consumption of a standard high-fat meal (680 kcal/m2 body surface area of a formula in which 86% of the calories were derived from fat), postprandial plasma TG, chylomicron-TG, and very-low-density lipoprotein (VLDL)-TG levels and postprandial areas were higher in men with SI (P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗