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In order to study the acute effects of exercise on adipose tissue metabolism, 27 sedentary male subjects, 18 to 27 years of age, performed a prolonged aerobic exercise test. Biopsies of adipose tissue were obtained from the suprailiac fat depot before and immediately after a 90-minute period of exercise on ergocycle at an average intensity of 88% of maximal heart rate. Fat cells, isolated by collagenase digestion, were measured for their glucose conversion into triglycerides and for lipolytic activity. Adipose tissue lipoprotein lipase activity released by heparin was also determined. Mean basal and insulin-stimulated glucose conversion into triglycerides decreased significantly with exercise (P less than .05) while adipose tissue lipoprotein lipase activity increased (P less than .01). Fat cell lipolysis increased during exercise only for its epinephrine-stimulated values (P less than .05). The total amount of work performed during the test was correlated only with changes in lipoprotein lipase activity (r = .42, P less than .05). Finally, the changes induced by exercise in lipoprotein lipase activity (r = .37, P less than .05) and insulin-stimulated glucose conversion into triglycerides (r = .61, P less than .01) were positively correlated with fat cell weight. These results indicate that adipose tissue metabolic activities are selectively influenced by endurance exercise. They also suggest that these metabolic changes are not closely coupled with the amount of work performed in a prolonged exercise bout.

To study the influence of endurance training on glucose conversion into fat cell triglycerides, 24 (13 women, 11 men) inactive subjects (25.0 +/- 3.8 yr of age) took part in a 20-wk ergocycle training program 4 days and increasing to 5 days/wk, 40–45 min/day, starting at 60% and increasing to 85% of the heart rate reserve. Several body fatness indicators were measured before and after the training program: seven skinfold thicknesses, percent fat, and mean fat cell weight. Fat cell basal and maximal insulin-stimulated glucose conversion into triglycerides were also determined using [14C]glucose. Body fatness indicators decreased significantly after training only in male subjects (P less than 0.05). Basal and maximal insulin-stimulated glucose conversion into triglycerides increased significantly with training (P less than 0.05): pretest values (nanomoles glucose per hour per 10(6) cells) being 24.9 +/- 2.1 and 28.7 +/- 2.5, while post-test values were 30.1 +/- 3.2 and 33.0 +/- 3.4 for basal and insulin-stimulated values, respectively. However, this lipogenic increase was only observed in male subjects (P less than 0.01). Changes in body fatness indicators induced by training were negatively correlated with changes induced in fat cell glucose conversion into triglycerides (-0.24 less than or equal to r less than or equal to -0.45). These results demonstrate that endurance training increases fat cell glucose conversion into triglycerides and suggest that adipose tissue metabolism is part of the adaptive response to training. Moreover, it appears that adipose tissue response to aerobic training is more efficient in males than in females.

Four hundred and seventy-two subjects (234 women and 238 men), 18 to 50 years of age, participated in percent body fat determination from underwater weighing, assessment of 6 subcutaneous skinfold thicknesses, and a 12-hour fast blood sampling for measurement of serum triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), total cholesterol (CHOL), and HDL-C/CHOL ratio. Even though women were significantly fatter than men, they had lower TG, CHOL, and higher values of HDL-C/CHOL ratio. Correlational and variance analyses showed that body fatness seemed to be more closely associated with serum lipids in men than in women. Moreover, the relationship between each skinfold and serum lipids indicated that subscapular and abdominal fat depots are more closely associated with serum lipids than other fat depots in men. In women, correlations were lower and regional differences attenuated. Furthermore, the regional trend observed in men remained significant after correction for concomitant variables such as age, cigarette smoking, habitual energy intake and energy expenditure, maximal aerobic power, and alcohol consumption. However, no effect of increasing body fatness was noted on HDL-C levels in women. Results of this study suggest that measurement of subscapular and abdominal fat should be considered when interpreting the blood lipid profile, particularly in males. A higher percentage of fat must be present in women than in men to observe alterations in serum lipids.

The effect of caffeine on the resting metabolic rate (RMR) was investigated in endurance exercise-trained (N = 14) and inactive (N = 10) male individuals. Subjects were also classified into regular and non-regular consumers of caffeine. After an overnight fast, RMR was measured using an indirect calorimetry open circuit system. Thereafter, subjects orally consumed 300 mg of caffeine, after which RMR was measured for 90 min. Five of the exercise-trained subjects were also studied after the administration of a placebo. Plasma concentrations of glycerol and free fatty acid and respiratory exchange ratio (R) were measured at each 15-min interval. Before caffeine ingestion, no significant differences were observed in RMR, R, glycerol, free fatty acid and blood pressure levels between exercise-trained and inactive groups. Following caffeine consumption, a three-way analysis of variance revealed that inactive subjects exhibited a greater increase (P less than 0.05) in RMR than did exercise-trained subjects. No significant differences were observed in RMR response between regular or nonregular consumers of caffeine. Moreover, no differences were observed in glycerol, free fatty acid, heart rate, and blood pressure response between exercise-trained and inactive subjects and between regular and non-regular consumers of caffeine. These results suggest that endurance training results in a reduced thermogenic response to a caffeine challenge.

The concentrations of cefamandole, cloxacillin and fusicid acid were measured in the serum and heart tissue of 100 recipients of these drugs before cardiac surgery. During cardiopulmonary bypass, mean (+/- standard deviation) peak concentrations in serum of all patients were 63.0 +/- 34.0 micrograms of cefamandole per ml, 30.8 +/- 17.7 micrograms of cloxacillin per ml, and 32.4 +/- 10.8 micrograms of fusidic acid per ml. Mean (+/- standard deviation) concentrations in atrial appendages taken 1 h (+/- 15 min) after infusion were 21.3 +/- 11.0 micrograms of cefamandole per g, 23.8 +/- 17.3 micrograms of cloxacillin per g, and 10.7 +/- 4.2 micrograms of fusidic acid per g. No cloxacillin could be detected in 5 of 39 heart specimens. Mean tissue-to-serum ratios at 1 h for cefamandole, cloxacillin, and fusidic acid were respectively 0.35, 0.73, and 0.33. Fusidic acid, a drug which is highly effective in vitro against both methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis, was detectable in heart tissue in concentrations which were 12 times higher than the MICs of this agent against these resistant microorganisms.

The aims of this controlled experiment were to investigate the effects of short-term aerobic exercise training on plasma lipid and lipoprotein concentrations and the role of heredity in determining the individual variation observed in the lipoprotein-lipid response. Six pairs of male monozygotic (MZ) twins were subjected to an exercise training program that induced a 22,000 kcal energy deficit after 22 consecutive days of training. This program significantly reduced body weight, percent body fat, and subcutaneous fat and significantly increased maximal oxygen consumption (VO2max) (p less than 0.005). The plasma insulin response to an oral glucose challenge was markedly reduced after training (p less than 0.001). Plasma triglyceride concentration decreased and the high density lipoprotein cholesterol (HDL-CHOL)/CHOL ratio increased with training (p less than 0.05). Subjects also displayed substantial individual variation in their response to exercise training, but the changes in plasma CHOL, apolipoprotein (apo) B low density lipoprotein cholesterol (LDL-CHOL), HDL-CHOL, and the HDL-CHOL/CHOL ratio tended to be similar within MZ twin pairs (0.67 less than or equal to ri less than or equal to 0.92; 0.05 greater than p less than 0.0001) thus indicating a significant effect of heredity on the sensitivity of plasma lipids and lipoproteins to exercise training.(ABSTRACT TRUNCATED AT 250 WORDS)

The contribution of genetic and environmental factors in serum triglycerides (TG), total cholesterol (CHOL), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), and HDL-C/CHOL ratio were studied in 1630 subjects from 375 families of French descent by using a path analysis procedure. Familial correlations were computed in several pairs of biological relatives and relatives by adoption after adjustment for age and gender effects and after further adjustment for physical fitness, level of habitual physical activity, total body fat and fat distribution, diet, smoking, and alcohol consumption. The model of path analysis allowed the separation of transmissible variance (t2) into genetic (h2) and cultural (b2) components of inheritance. Under the most parsimonious solution and after adjustment for age, gender, and concomitants, the transmissible variance was entirely accounted for by genetic factors (t2 = h2), with h2 estimates of 0.52, 0.55, 0.60, and 0.63 for TG, CHOL, LDL-C, HDL-C, and HDL-C/CHOL, respectively. These estimates were similar to those obtained after adjustment for age and gender effects only. The contribution of nontransmissible environmental factors ranged from 0.48 for TG to 0.37 for HDL-C/CHOL ratio. These results suggest that both genetic and environmental factors contribute to the variation in blood lipids and lipoproteins in this population and that nongenetic influences are not associated with cultural factors transmitted across generations.

Low plasma levels of HDL cholesterol have been as- sociated with an increased risk of coronary heart disease. HDL particles are heterogeneous with respect to size and apolipo- protein content. The objective of the present study was to develop a method to generate lipid-stainable calibrators that would allow the assessment of HDL particle size from whole plasma, using polyacrylamide gradient gel electrophoresis (PAGGE). Lipid-stainable HDL calibrators were obtained by subjecting isolated red blood cells to hemolysis either by freezing at � 20 or � 80 � C overnight or by rapid exposure to liquid nitrogen and mixing of the hemolysis products with plasma aliquots. All three methods were highly reproducible in producing Sudan black lipid-stainable HDL calibrators ranging from 75 to 200 A. The assessment of HDL particle size with these lipid-stainable HDL calibrators was also highly reproducible, with a coeffi- cient of variation below 5.5%. These lipid-stainable HDL calibrators simplify the assessment of HDL particle size by PAGGE using whole plasma, without the need for costly, time- consuming ultracentrifugation procedures. —Perusse, M., A. Pascot, J-P. Despres, C. Couillard, and B. Lamarche. A new method for HDL particle sizing by polyacrylamide gradient gel electrophoresis using whole plasma. J. Lipid Res. 2001. 42: 1331- 1334.

The aim of the present study was to evaluate the relation among alcohol consumption, the metabolic syndrome, and the risk of ischemic heart disease (IHD). The study was conducted in a cohort of 1966 men from the Quebec Cardiovascular Study. All men were initially free of IHD and, during the follow-up period of 13 y, 219 first cases of IHD were diagnosed. Alcohol consumption was determined by calculating the g/d intake based on standard portions of beer, wine, and spirits. Metabolic syndrome was diagnosed according to a modification of the National Cholesterol Education Program Adult Treatment Panel III definition. Men who consumed $15.2 g of alcohol/d (4th quartile of the distribution) were younger (P , 0.001), had elevatedplasma HDL-C concentrations (P ,0.001), and lower plasma concentrations of insulin (P ¼0.01),CRP (P ¼ 0.01), and fibrinogen (P , 0.001) than men in the 1st quartile (,1.3 g of alcohol/d). After adjustment for a series of coronary risk factors, alcohol consumption $15.2 g/d was associated with a 39% reduction in the 13-y risk of IHD [relative risk (RR) of IHD ¼ 0.61, P ¼ 0.02]. Finally, an alcohol consumption ,15.2 g/d was associated with an increase of the risk of IHD in men with the metabolic syndrome (RR ¼ 2.24, P , 0.001) but not in men without the metabolic syndrome (RR ¼ 1.31, P ¼ 0.22). These results confirm that moderate daily alcohol consumption has cardioprotective properties and suggest that the effects may be more important in subjects with a deteriorated risk profile, such as those with the metabolic syndrome. J. Nutr. 136: 3027‐3032, 2006.

Background The Canadian Alliance for Healthy Hearts and Minds (CAHHM) is a pan-Canadian, prospective, multi-ethnic cohort study being conducted in Canada. The overarching objective of the CAHHM is to understand the association of socio-environmental and contextual factors (such as societal structure, activity, nutrition, social and tobacco environments, and access to health services) with cardiovascular risk factors, subclinical vascular disease, and cardiovascular and other chronic disease outcomes. Methods/Design Participants between 35 and 69 years of age are being recruited from existing cohorts and a new First Nations Cohort to undergo a detailed assessment of health behaviours (including diet and physical activity), cognitive function, assessment of their local home and workplace environments, and their health services access and utilization. Physical measures including weight, height, waist/hip circumference, body fat percentage, and blood pressure are collected. In addition, eligible participants undergo magnetic resonance imaging (MRI) of the brain, heart, carotid artery and abdomen to detect early subclinical vascular disease and ectopic fat deposition. Discussion CAHHM is a prospective cohort study designed to investigate the impact of community level factors, individual health behaviours, and access to health services, on cognitive function, subclinical vascular disease, fat distribution, and the development of chronic diseases among adults living in Canada. Electronic supplementary material The online version of this article (doi:10.1186/s12889-016-3310-8) contains supplementary material, which is available to authorized users.

We compared the effects of ad libitum consumption of a defined high complex carbohydrate (CHO) diet (% of energy: CHO, 58.3; fat, 25.8) vs. a defined high monounsaturated fatty acid (MUFA) diet (% of energy: CHO, 44.7; fat, 40.1; MUFA, 22.5) on LDL electrophoretic characteristics. Healthy men [n = 65; age, 37.5 +/- 11.2 (mean +/- SD) y; BMI, 29.2 +/- 4.9 kg/m2] were randomly assigned to one of the two diets that they consumed for 6-7 wk. The high CHO diet significantly reduced body weight (-2%). The diet-induced reduction in plasma LDL cholesterol (C) levels in the high-CHO diet group was due mainly to concurrent reductions in the cholesterol content of small (

Objective: It is commonly recognized that genetic, environmental, behavioral, and social factors are involved in the development of obesity. The family environment may play a key role in shaping children's eating behaviors. The purpose of this study was to estimate the degree of familial resemblance in eating behavioral traits (cognitive dietary restraint, disinhibition, and susceptibility to hunger). Research Methods and Procedures: Eating behavioral traits were assessed with the Three-Factor Eating Questionnaire in 282 men and 402 women (202 families) from the Quebec Family Study. Familial resemblance for each trait (adjusted for age, sex, and BMI) was investigated using a familial correlation model. Results: The pattern of familial correlation showed significant spouse correlation for the three eating behavior phenotypes, as well as significant parent-offspring and sibling correlations for disinhibition and susceptibility to hunger. According to the most parsimonious model, generalized heritability estimates (including genetic and shared familial environmental effects) reached 6%, 18%, and 28% for cognitive dietary restraint, disinhibition, and susceptibility to hunger, respectively. Discussion: These results suggest that there is a significant familial component to eating behavioral traits but that the additive genetic component appears to be small, with generalized heritability estimates ranging from 6% to 28%. Thus, non-familial environmental factors and gene-gene and gene-environmental interactions seem to be the major determinants of the eating/behavioral traits.

Background: Dietary patterns play an important role in the control of body weight. Objective: The aim of this study was to verify whether changes in some dietary patterns over a 6-y follow-up period would be associated with weight changes. Design: A sample of 248 volunteers of the Quebec Family Study were measured twice (visit 1: 1989 –1994; visit 2: 1995–2000). Body weight, percentage body fat, subcutaneous skinfold thicknesses, and waist circumference measurements as well as 3-d dietary and physical activity records were obtained at each visit. At visit 2, all participants filled out a food-based questionnaire examining changes in the consumption of 10 food categories. To further investigate the relation between changes in food-group consumption and bodyweight changes, a total of 51 food subcategories were identified from dietary records. Results: A self-reported decrease in the consumption of food in the fat group or an increase in consumption in the fruit group from the food-based questionnaire predicted a lower increase in body weight and adiposity indicators over time. A more detailed examination of the change in food groups between diet records revealed that increases in the consumption of whole fruit as well as skimmed milk and partly skimmed milk were the 2 food patterns that negatively correlated with the changes of each body weight–related indicator. Conclusions: These results show that changes in the consumption of some specific food groups are associated with body-weight changes. Such specific eating patterns could help to improve obesity treatment and prevention. Am J Clin Nutr 2004;80:29 –37.

Peroxisome proliferator-activated receptor alpha (PPARalpha) is a member of the steroid hormone receptor super family involved in the control of cellular lipid utilization. This makes PPARalpha a candidate gene for type 2 diabetes and dyslipidemia. The aim of this study was to investigate whether genetic variation in the human PPARalpha gene can influence the risk of type 2 diabetes and dyslipidemia among French Canadians. We therefore first determined the genomic structure of human PPARalpha, and then designed intronic primers to sequence the coding region and the exon-intron boundaries of the gene in 12 patients with type 2 diabetes and in 2 nondiabetic subjects. Sequence analysis revealed the presence of a L162V missense mutation in exon 5 of one diabetic patient. Leucine 162 is contained within the DNA binding domain of the human PPARalpha gene, and is conserved among humans, mice, rats, and guinea pigs. We subsequently screened a sample of 121 patients newly diagnosed with type 2 diabetes and their age and sex-matched nondiabetic controls, recruited from the Saguenay-Lac-St-Jean region of Northeastern Quebec, for the presence of the L162V mutation by a PCR-RFLP based method. There was no difference in L162 homozygote or V162 carrier frequencies between diabetics and nondiabetics. However, whether diabetic or not, carriers of the V162 allele had higher plasma apolipoprotein B levels compared to noncarriers (P 5 0.05). To further this association, we screened another sample of 193 nondiabetic subjects recruited in the greater Quebec City area. Carriers of the V162 allele compared with homozygotes of the L162 allele had significantly higher concentrations of plasma total and LDL-apolipoprotein B as well as LDL cholesterol (P

Background Plasma C-reactive protein (CRP) levels recently have been identified as an emerging risk factor for ischemic heart disease (IHD). However, whether plasma CRP levels predict an increased risk for future IHD beyond traditional risk factors has yet to be evaluated in a large prospective, population-based study. Methods The association between elevated plasma CRP levels and the risk for future IHD was investigated in the prospective, population-based cohort of 2037 IHD-free middle-aged men from the Quebec Cardiovascular Study. During a 5-year follow-up, 105 first IHD events were recorded. Baseline plasma CRP levels were measured using a highly sensitive assay. Results High plasma CRP concentrations (equal to or above vs below the median level of 1.77 mg/L) were associated with a significant 1.8-fold increase in IHD risk (95% confidence interval [CI], 1.2-2.7). This association remained significant after adjustment for lipid risk factors but not when the simultaneous contribution of nonlipid traditional risk factors was taken into account. Multivariate analyses indicated that CRP level predicted short-term risk for IHD (events that occurred ≤2 years after the baseline evaluation), but not long-term risk (>2 years). Moreover, high plasma CRP levels predicted an increased risk for IHD, independent of any other confounder, in younger (≤55 years) but not in older (>55 years) individuals. Conclusion Plasma CRP levels may provide independent information on IHD risk only in younger middle-aged men and in the case of IHD events that may occur relatively soon after the baseline evaluation.

To determine whether a common quantitative trait locus (QTL) influences the variation of fasting triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) levels, we used a bivariate multipoint linkage analysis with 654 polymorphic markers in 99 white and 101 black families. The phenotypes were investigated under two conditions: at baseline and after a 20-week exercise training intervention. A maximum genome-wide bivariate LOD score of 3.0 (p = 0.00010) was found on chromosome 12q23-q24, located within the IGF1 gene (insulin-like growth factor 1, at 107 cM) for TG and HDL-C at baseline in whites. This bivariate linkage peak is considerably higher than the univariate linkage results at the same chromosome location for either trait (for TG, LOD = 2.07, p = 0.00108; for HDL-C, LOD = 2.04, p = 0.00101). The genetic correlations between baseline TG and HDL-C levels were -0.14 for the residual and -0.33 for the QTL components. Moreover, association analysis showed that TG, HDL-C, and IGF1 are significantly associated (p = 0.04). In conclusion, these results suggest that a QTL on chromosome 12q23-q24 influences the variation of plasma TG and HDL-C levels. Further investigation should confirm whether IGF1 or another nearby gene is responsible for the concomitant variation in TG and HDL-C levels.

Abstract The familial aggregation of lipids and lipoproteins and plasma postheparin triglyceride lipases was investigated in 86 Caucasian families participating in the HERITAGE Family study, a study investigating the role of genetic factors in the adaptation to exercise training and its relationships with cardiovascular disease risk factors. Accordingly, sedentary subjects were recruited, tested for a battery of measurements, exercise trained for 20 weeks, and were re-measured. The present report includes plasma levels of total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and triglycerides, and postheparin plasma lipoprotein lipase (LPL) and hepatic lipase (HL) activities measured in 437 sedentary individuals (171 parents and 266 adult offspring) before training. Significant familial resemblance was observed for all the age-adjusted phenotypes. The pattern of familial correlations reveals no spouse correlations but significant parent-offspring and sibling correlations for total cholesterol, HDL-cholesterol and LDL-cholesterol with heritability (h 2 ) estimates of 62%, 83%, and 50%, respectively. For plasma triglyceride concentrations (h 2 =55%) and HL activity (h 2 =40%), significant spouse correlations were found in addition to parent-offspring and sibling correlations, suggesting that common familial environment in addition to genetic factors contribute to the familial resemblance. For plasma LPL activity, there was no spouse correlation, but sex differences were found in the familial correlations with higher heritabilities in female pairs (h 2 =76%) compared to male pairs (h 2 =30%) and opposite-sex pairs (h 2 =44%). These results confirm the findings of previous family studies showing that genetic factors are major determinants of the familial resemblance in plasma lipids and lipoproteins and suggest the presence of sex differences in the heritability of postheparin LPL activity.

To investigate the effects of aerobic training on adipose tissue morphology and fat distribution, several indicators of body fatness (percent body fat, seven subcutaneous skinfolds, fat cell weight) were assessed in 13 sedentary male subjects (SS) submitted to a 20-wk aerobic training program and in 20 male long-distance runners (LDR). The LDR subjects had a mean +/- SD VO2max of 65.9 +/- 6.5 ml . min-1 . kg-1 and averaged 120 km . wk-1. Training increased the VO2max values of the SS group significantly (pre: 41.9 +/- 7.0 vs post: 53.4 +/- 6.4 ml . kg-1 . min-1; P less than 0.001) and decreased significantly percent body fat (P less than 0.01), sum of skinfolds (P less than 0.01), and fat cell weight (P less than 0.05). Trunk skinfolds were more altered by training than extremity skinfolds, with reductions of 22 and 12.5%, respectively. Significant correlations were found between fat cell weight and percent body fat in SS before and after training (r = 0.75; P less than 0.01), while no significant relationship was noted in the LDR group. Moreover, using the sum of skinfolds divided by percent fat or by fat mass to reflect the proportion of subcutaneous fat to total fat, the LDR subjects exhibited less subcutaneous fat than the SS group (P less than 0.01) and training did not alter these ratios in the SS group. These results suggest that 20 wk of aerobic training can alter body fatness in men but that the induced fat loss does not seem to deplete preferentially subcutaneous fat.

Screening for increased waist circumference and hypertriglyceridemia (the hypertriglyceridemic-waist phenotype) is an inexpensive approach to identify patients at risk of coronary artery disease in apparently healthy individuals who may be at increased risk of type 2 diabetes and coronary heart disease because of an excess of intra-abdominal (visceral) fat. We examined the relationship between the hypertriglyceridemic-waist and selected cardiometabolic risk factors in HIV individuals. Supplement: Abstracts of the Tenth International Congress on Drug Therapy in HIV Infection http://www.biomedcentral.com/content/pdf/1758-2652-13-S4-info.pdf Conference: Tenth International Congress on Drug Therapy in HIV Infection 7-11 November 2010 Glasgow, UK (Published: 8 November 2010) doi:10.1186/1758-2652-13-S4-P73 Cite this article as: Guaraldi et al.: Hypertriglyceridemic waist identifies HIV+ men and women at increased cardiometabolic risk. Journal of the International AIDS Society 2010 13(Suppl 4):P73. Full text: PubMed Central: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3113079/