The use of fasting vs. non-fasting triglyceride concentration for estimating the prevalence of high LDL-cholesterol and metabolic syndrome in population surveys

<p>Abstract</p> <p>Background</p> <p>For practical reasons it is not easy to obtain fasting samples in large population health surveys. Non-fasting triglyceride (Tg) values are difficult to interpret. The authors compared the accuracy of statistically corrected non-fasting Tg values with true fasting values and estimated the misclassification of subjects with high low-density lipoprotein cholesterol (LDL-C) and the metabolic syndrome.</p> <p>Methods</p> <p>Non-fasting blood was obtained from a population-based sample of 4282 individuals aged 24-75 years in the National FINRISK 2007 Study. Fasting blood samples were drawn from the same persons 3 months later. Non-fasting serum Tg values were converted into fasting values using previously published formula. LDL-C was calculated and classification of the metabolic syndrome was carried out according to three different latest guidelines.</p> <p>Results</p> <p>The median (25^th, 75th percentile) non-fasting serum Tg concentration was 1.18 (0.87, 1.72) mmol/L and after postprandial correction 1.06 (0.78, 1.52) mmol/L. The true-fasting serum Tg concentration was 1.00 (0.75, 1.38) mmol/L (<it>P </it>< 0.001) vs. non-fasting and corrected value. Bias of the corrected value was +5.9% compared with the true-fasting Tg. Of the true fasting subjects, 56.4% had LDL-C ≥3.00 mmol/L. When calculated using non-fasting serum Tg, the prevalence of high LDL-C was 51.3% and using statistically corrected Tg it was 54.8%. The prevalence of metabolic syndrome was 35.5% among fully fasted persons and among non-fasting subjects 39.7%, which after statistical correction of Tg decreased to 37.6% (P < 0.001 for all comparisons).</p> <p>Conclusions</p> <p>Correction of non-fasting serum Tg to fasting values plays a minor role in population studies but nevertheless reduces misclassification of calculated high LDL-C from 5.1 to 1.6% and the metabolic syndrome from 4.2 to 2.1%.</p

Exercise training with dietary counselling increases mitochondrial chaperone expression in middle-aged subjects with impaired glucose tolerance

<p>Abstract</p> <p>Background</p> <p>Insulin resistance and diabetes are associated with increased oxidative stress and impairment of cellular defence systems. Our purpose was to investigate the interaction between glucose metabolism, antioxidative capacity and heat shock protein (HSP) defence in different skeletal muscle phenotypes among middle-aged obese subjects during a long-term exercise and dietary intervention. As a sub-study of the Finnish Diabetes Prevention Study (DPS), 22 persons with impaired glucose tolerance (IGT) taking part in the intervention volunteered to give samples from the <it>vastus lateralis </it>muscle. Subjects were divided into two sub-groups (IGTslow and IGTfast) on the basis of their baseline myosin heavy chain profile. Glucose metabolism, oxidative stress and HSP expressions were measured before and after the 2-year intervention.</p> <p>Results</p> <p>Exercise training, combined with dietary counselling, increased the expression of mitochondrial chaperones HSP60 and glucose-regulated protein 75 (GRP75) in the <it>vastus lateralis </it>muscle in the IGTslow group and that of HSP60 in the IGTfast group. In cytoplasmic chaperones HSP72 or HSP90 no changes took place. In the IGTslow group, a significant positive correlation between the increased muscle content of HSP60 and the oxygen radical absorbing capacity values and, in the IGTfast group, between the improved VO_2maxvalue and the increased protein expression of GRP75 were found. Serum uric acid concentrations decreased in both sub-groups and serum protein carbonyl concentrations decreased in the IGTfast group.</p> <p>Conclusion</p> <p>The 2-year intervention up-regulated mitochondrial HSP expressions in middle-aged subjects with impaired glucose tolerance. These improvements, however, were not correlated directly with enhanced glucose tolerance.</p

Work-Family Life Courses and Metabolic Markers in the MRC National Survey of Health and Development

The aim was to investigate whether the combined work-family life courses of British men and women were associated with differences in metabolic markers?waist circumference, blood pressure, high density lipoprotein cholesterol, triglycerides, and glycated haemoglobin?in mid-life. We used data from the Medical Research Council?s National Survey of Health and Development?the 1946 British birth cohort. Multi-channel sequence analysis was used to create a typology of eight work-family life course types combining information on work, partnerships and parenthood between ages 16?51. Linear regression tested associations between work-family types and metabolic outcomes at age 53 on multiply imputed data (20 imputations) of >2,400 participants. Compared with men with strong ties to employment and early transitions to family life, men who made later transitions to parenthood and maintained strong ties to paid work had smaller waist circumferences (-2.16cm, 95% CI: -3.73, -0.59), lower triglycerides (9.78% lower, 95% CI: 0.81, 17.94) and lower blood pressure (systolic: -4.03mmHg, 95% CI: -6.93, -1.13; diastolic: -2.34mmHg, 95% CI: -4.15, -0.53). Married men and women who didn?t have children had increased high density lipoprotein cholesterol (7.23% higher, 95% CI: 0.68, 14.21) and lower waist circumferences (-4.67cm, 95% CI: -8.37, -0.97), respectively. For men later transitions to parenthood combined with strong ties to paid work were linked to reduced metabolic risk in mid-life. Fewer differences between work-family types and metabolic markers were seen for women

Behavioural observations in gunn rats

The Gunn rat is a hooded mutant of albino rat with various biochemical defects, including a low UDP-glucuronosyl-transferase activity. As a consequence, about half of their offspring are jaundiced from birth, due to high free bilirubin levels, and develop widespread brain damage. The behaviour of both jaundiced and nonjaundiced Gunn rats was studied in four different tests in a shuttle-box and in a stepthrough passive avoidance situation, and compared with that of normal hooded rats. No differences among groups were found in performance of shuttle responses to a tone in a pseudoconditioning paradigm in which tones and shocks were given at random. However, rats from the two Gunn groups made less shuttlings to the tone in two tests that involved an avoidance contingency (each response cancelled one shock). In addition, nonicteric Gunn rats also performed poorly in a classical conditioning test in the shuttle-box (tones and shocks paired on every trial regardless of responses). This last deficiency of non-icteric Gunn rats may be explained by their higher tendency to freeze in situations involving stimulus-stimulus interactions. They also showed a higher latency than that of the two other groups to enter the dark side of the step-through apparatus on their first exposure to it. All animals seemed to learn the passive-avoidance task to the same extent, however, as shown in a retest carried out 48 h later. Both Gunn groups were hypersensitive to the stereotyped-behaviour-inducing action of apomorphine (0.125–1.0 mg/kg, i.p.), but all groups were about equally sensitive to that of d -amphetamine sulfate (0.5–4.0 mg/kg). Since apomorphine is disposed of by glucuronidation, this might be explained by the low UDP-glucuronosyl-transferase activity known to exist in the Gunn animals. The present results show that additional genetic defects have developed by in-breeding in the Gunn population, which are unrelated to brain damage caused by bilirubin, and which can be well characterized from a behavioural standpoint.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46403/1/213_2004_Article_BF00426881.pd

Metabolic Consequences and Vulnerability to Diet-Induced Obesity in Male Mice under Chronic Social Stress

Social and psychological factors interact with genetic predisposition and dietary habit in determining obesity. However, relatively few pre-clinical studies address the role of psychosocial factors in metabolic disorders. Previous studies from our laboratory demonstrated in male mice: 1) opposite status-dependent effect on body weight gain under chronic psychosocial stress; 2) a reduction in body weight in individually housed (Ind) male mice. In the present study these observations were extended to provide a comprehensive characterization of the metabolic consequences of chronic psychosocial stress and individual housing in adult CD-1 male mice. Results confirmed that in mice fed standard diet, dominant (Dom) and Ind had a negative energy balance while subordinate (Sub) had a positive energy balance. Locomotor activity was depressed in Sub and enhanced in Dom. Hyperphagia emerged for Dom and Sub and hypophagia for Ind. Dom also showed a consistent decrease of visceral fat pads weight as well as increased norepinephrine concentration and smaller adipocytes diameter in the perigonadal fat pad. On the contrary, under high fat diet Sub and, surprisingly, Ind showed higher while Dom showed lower vulnerability to obesity associated with hyperphagia. In conclusion, we demonstrated that social status under chronic stress and individual housing deeply affect mice metabolic functions in different, sometime opposite, directions. Food intake, the hedonic response to palatable food as well as the locomotor activity and the sympathetic activation within the adipose fat pads all represent causal factors explaining the different metabolic alterations observed. Overall this study demonstrates that pre-clinical animal models offer a suitable tool for the investigation of the metabolic consequences of chronic stress exposure and associated psychopathologies

Fish consumption, omega-3 fatty acids, and environmental contaminants in relation to low-grade inflammation and early atherosclerosis

Available online 22 October 2012