Exercise of low energy expenditure along with mild energy intake restriction acutely reduces fasting and postprandial triacylglycerolaemia in young women

A single bout of prolonged, moderate-intensity endurance exercise lowers fasting and postprandial TAG concentrations the next day. However, the TAG-lowering effect of exercise is dose-dependent and does not manifest after light exercise of low energy cost ( < 2 MJ). We aimed to investigate whether superimposing mild energy intake restriction to such exercise, in order to augment total energy deficit, potentiates the hypotriacylglycerolaemic effect. Eight healthy, sedentary, premenopausal women (age 27.1 (sem 1.3) years; BMI 21.8 (sem 0.9) kg/m2) performed two oral fat tolerance tests in the morning on two different occasions: once after a single bout of light exercise (100 min at 30 % of peak oxygen consumption; net energy expenditure 1.04 (sem 0.01) MJ) coupled with mild energy intake restriction (1.39 (sem 0.22) MJ) on the preceding day, and once after resting coupled with isoenergetic feeding on the preceding day (control). Fasting plasma TAG, TAG in the TAG-rich lipoproteins (TRL-TAG) and serum insulin concentrations were 18, 34 and 30 % lower, respectively, after exercise plus diet compared with the control trial (P < 0.05). Postprandial concentrations of plasma TAG and TRL-TAG were 19 and 27 % lower after exercise plus diet compared with the control condition (P < 0.01), whereas postprandial insulin concentrations were not different. It is concluded that a combination of light exercise along with mild hypoenergetic diet may be a practical and feasible intervention to attenuate fasting and postprandial triacylglycerolaemia, especially for people who cannot exercise for prolonged periods of time at moderate-to-high intensities, such as many sedentary individuals.     

Short-term walnut consumption increases circulating total adiponectin and apolipoprotein A concentrations, but does not affect markers of inflammation or vascular injury in obese humans with the metabolic syndrome: data from a double-blinded, randomized, placebo-controlled study

Long-term consumption of walnuts is associated with lower cardiovascular disease risk in epidemiological studies, possibly through improvements in lipid profile and endothelial function. It remains to be elucidated how soon after initiation of walnut consumption beneficial effects on lipid profile and biomarkers of inflammation or vascular injury can be observed. Fifteen obese subjects (9 men and 6 women; age, 58 ± 2.5 years; body mass index, 36.6 ± 1.7 kg/m(2)) with the metabolic syndrome participated as inpatients in a randomized, double-blinded, placebo-controlled crossover study involving short-term placebo or walnut-enriched diet (48 g/d for 4 days). Apolipoproteins and markers of inflammation and vascular injury were measured before and after consumption of the experimental diets. Consumption of walnuts was associated with a statistically significant increase in serum apolipoprotein A concentrations (P = .03), but did not affect circulating levels of fetuin A, resistin, C-reactive protein, serum amyloid A, soluble intercellular adhesion molecules 1 and 3, soluble vascular cell adhesion protein 1, interleukins 6 and 8, tumor necrosis factor α, E-selectin, P-selectin, and thrombomodulin. Four days of walnut consumption (48 g/d) leads to mild increases in apolipoprotein A concentrations, changes that may precede and lead to the beneficial effects of walnuts on lipid profile in obese subjects with the metabolic syndrome.     

Effects of yoghurt enriched with free plant sterols on the levels of serum lipids and plant sterols in moderately hypercholesterolaemic subjects on a high-fat diet

Apparently, one of the primary reasons for purchasing organic food is the perception that it is more nutritious than conventional food. Given the increasing interest towards organic food products, it is imperative to review the existing literature concerning the nutritional value of the produce, and to determine to what extent are consumer expectations met. There are only few well-controlled studies that are capable of making a valid comparison and, therefore, compilation of the results is difficult and generalisation of the conclusions should be made with caution. In spite of these limitations, however, some differences can be identified. Although there is little evidence that organic and conventional foods differ in respect to the concentrations of the various micronutrients (vitamins, minerals and trace elements), there seems to be a slight trend towards higher ascorbic acid content in organically grown leafy vegetables and potatoes. There is also a trend towards lower protein concentration but of higher quality in some organic vegetables and cereal crops. With respect to the rest of the nutrients and the other food groups, existing evidence is inadequate to allow for valid conclusions. Finally, animal feeding experiments indicate that animal health and reproductive performance are slightly improved when they are organically fed. A similar finding has not yet been identified in humans. Several important directions can be highlighted for future research; it seems, however, that despite any differences, a well-balanced diet can equally improve health regardless of its organic or conventional origin.     

Somatostatin Analogs for Pancreatic Neuroendocrine Tumors: Any Benefit When Ki‐67 Is ≥10%?

BackgroundLong‐acting somatostatin analogs (SSAs) are the primary first‐line treatment of well‐differentiated advanced gastroenteropancreatic neuroendocrine tumors (NETs), but data about their efficacy in pancreatic NETs (panNETs) with Ki‐67 ≥10% are still limited.Materials and MethodsTo assess the clinical outcomes of advanced, nonfunctioning, well‐differentiated panNETs with Ki‐67 ≥10% receiving first‐line long‐acting SSAs in a real‐world setting, we carried out a retrospective, multicenter study including patients treated between 2014–2018 across 10 centers of the NET CONNECT Network. The primary endpoints were time to next treatment (TNT) and progression‐free survival (PFS), whereas overall survival (OS) and treatment safety were secondary endpoints.ResultsA total of 73 patients were included (68 grade [G]2, 5 G3), with liver metastases in 61 cases (84%). After a median follow‐up of 36.4 months (range, 6–173), the median TNT and PFS were 14.2 months (95% confidence interval [CI], 11.6–16.2) and 11.9 months (95% CI, 8.6–14.1) respectively. No statistically significant difference was observed according to the somatostatin analog used (octreotide vs. lanreotide), whereas increased tumor grade (hazard ratio [HR], 4.4; 95% CI, 1.2–16.6; p = .04) and hepatic tumor load (HR, 2; 95% CI, 1–4; p = .03) were independently associated with shortened PFS. The median OS recorded was 86 months (95% CI, 56.8–86 months), with poor outcomes observed when the hepatic tumor burden was >25% (HR, 3.4; 95% CI, 1.2–10; p = .01). Treatment‐related adverse events were reported in 14 patients, most frequently diarrhea.ConclusionSSAs exert antiproliferative activity in panNETs with Ki‐67 ≥10%, particularly in G2 tumors, as well as when hepatic tumor load is ≤25%.Implications for PracticeThe results of the study call into question the antiproliferative activity of somatostatin analogs (SSAs) in pancreatic neuroendocrine tumors with Ki‐67 ≥10%. Patients with grade 2 tumors and with hepatic tumor load ≤25% appear to derive higher benefit from SSAs. Prospective studies are needed to validate these results to optimize tailored therapeutic strategies for this specific patient population.     

Women produce fewer but triglyceride-richer very low-density lipoproteins than men

CONTEXT: Very low-density lipoproteins (VLDL) are a major risk factor for cardiovascular disease. The concentrations of VLDL particles and VLDL-triglyceride (TG) in plasma are lower in women than men, but the mechanisms responsible for these differences are unclear. OBJECTIVE: The objective of the study was to investigate the effects of sex on VLDL-TG and VLDL-apolipoprotein B-100 (apoB-100) metabolism. EXPERIMENTAL DESIGN AND MAIN OUTCOME MEASURES: We measured basal VLDL-TG and VLDL-apoB-100 kinetics by using stable isotope labeled tracers. SETTING/PARTICIPANTS: Twenty-six healthy, lean subjects (13 men, aged 29+/-5 yr; 13 women, aged 28+/-6 yr) were studied in the General Clinical Research Center at Washington University School of Medicine. RESULTS: VLDL-TG and VLDL-apoB-100 concentrations were less in women than men (P<0.05). The secretion rate of VLDL-TG was approximately 70% greater (P<0.05), whereas the secretion rate of VLDL-apoB-100 (i.e. VLDL particles) was approximately 20% less (P<0.05) in women than men. The molar ratio of VLDL-TG and VLDL-apoB-100 secretion rates was therefore more than double (P<0.05) in women than men. VLDL-TG plasma clearance rate was approximately 70% greater in women than men (P<0.05), whereas VLDL-apoB-100 plasma clearance rate was not different between sexes. However, VLDL-TG and VLDL-apoB-100 mean residence times in plasma were both shorter (by 45 and 25%, respectively; P<0.05) in women than men. CONCLUSIONS: Increased VLDL-TG plasma clearance is responsible for lower VLDL-TG concentration, whereas decreased VLDL-apoB-100 secretion rate, combined with shorter VLDL-apoB-100 residence time in plasma, is responsible for lower VLDL-apoB-100 concentration in women than men. The greater molar ratio of VLDL-TG and VLDL-apoB-100 secretion rates suggests that the liver in women secretes fewer but TG-richer VLDL particles than the liver in men.     

Behavioral and physiological indices related to BMI in a cohort of primary schoolchildren in Greece.

The purpose of this study was to investigate the differences between normal weight and overweight primary schoolchildren in terms of certain cardiovascular disease (CVD) risk factors and furthermore to identify behavioral correlates significantly affecting their body mass index (BMI). The sample consisted of 198 children with a mean age of 11.5 +/- 0.4 years (106 females and 92 males). Data was obtained on children anthropometry, plasma lipids, plasma glucose, dietary intake, cardiorespiratory fitness, and physical activity. Significant gender differences were observed for most of these parameters, with boys being more active and fit but also spending more time on sedentary activities and exhibiting higher intake of energy and fat compared to girls. Using the International Obesity Task Force's (IOTF) BMI cut-off points, the prevalence of overweight and obesity was estimated to be 35.6% and 6.7% among boys and 25.7% and 6.7% among girls, respectively. Overweight and obese children had higher levels of plasma triglycerides (TG) and total cholesterol to HDL-cholesterol (TC/HDL-C) ratio and lower levels of HDL-C and physical fitness compared to their normal-weight peers. Among the behavioral variables tested, only participation in organized sports, cardiorespiratory fitness, and TV watching were significantly correlated with BMI, while energy and fat intake were found to have no significant effect. The current study suggests that even in childhood, overweight and obesity are indicative of an unfavorable lipidemic profile. Among the behavioral parameters known to affect BMI, those found to exert a significant effect were organized physical activities, cardiorespiratory fitness, and TV watching, but not energy or fat intake.     

Association between Serum Vitamin D Metabolites and Metabolic Function in Healthy Asian Adults

The association between low vitamin D status and the development of type 2 diabetes mellitus is well established; however, intervention trials that increased serum vitamin D (through ultraviolet B exposure or dietary supplementation) provide mixed outcomes. Recent evidence suggests that metabolites directly related to vitamin D receptor activation—1α,25-dihydroxyvitamin D₃ and 24R,25-dihydroxyvitamin D₃—may be better markers of vitamin D repletion status. We tested the hypothesis that a vitamin D metabolite (VDM) index, calculated as the sum of normalized fasting serum concentrations of 1α,25-dihydroxyvitamin D₃ and 24R,25-dihydroxyvitamin D₃, is associated with metabolic function. We measured subcutaneous and visceral adipose tissue volume, intrahepatic triglyceride content, maximum oxygen uptake, insulin sensitivity (4 h hyperinsulinemic-euglycemic clamp), and insulin secretion (3 h meal tolerance test with mathematical modeling) and calculated the VDM index in 65 healthy Asian adults. Subjects with a low VDM index had lower peripheral insulin sensitivity and beta-cell function compared to subjects with a high VDM index (both p < 0.05), matched for age, sex, BMI, and serum 25-hydroxyvitamin D₃. Serum 25-hydroxyvitamin D₃ was not associated with peripheral insulin sensitivity or beta-cell function. Our results suggest that, rather than enhancing vitamin D substrate availability, upregulation of vitamin D action is more likely to lead to improvements in glucose homeostasis.     

Plasma homocysteine concentrations in Greek children are influenced by an interaction between the methylenetetrahydrofolate reductase C677T genotype and folate status

Risk factors established at young ages may set the stage for later cardiovascular disease (CVD). Elevated total homocysteine (tHcy) in blood is an emerging risk factor for CVD, yet few studies have been conducted in children, especially in the Mediterranean. We described plasma tHcy concentrations in a group of healthy Greek children and examined its relation with physiologic, metabolic, and genetic variables. Fasting blood samples were collected from 186 students, 11.6 +/- 0.4 years old, and tHcy, folate, vitamin B-12, and routine biochemistry variables in plasma were measured. The methylenetetrahydrolate reductase (MTHFR) C677T genotype was determined and anthropometric and dietary data were obtained. The distribution of tHcy was positively skewed with a median of 7.9 micromol/L (mean: 8.2 +/- 2.3 micromol/L; range: 4.4-22.2 micromol/L). tHcy was inversely related to plasma folate (r = -0.34, P < 0.0001), vitamin B-12 (r = -0.20, P = 0.008), and glucose (r = -0.15, P = 0.045). An interaction between the MTHFR genotype and plasma folate on tHcy was detected (P = 0.047). Specifically, the homozygous mutant TT genotype was associated with higher tHcy only in children with lower plasma folate (< 19.9 nmol/L), (P = 0.012). In our sample of healthy Greek children, plasma tHcy concentrations were higher than values reported in children of Northern European descent and were associated with folate, vitamin B-12, and glucose in plasma. The results also show that, similar to adults, plasma folate concentration is important in determining the contribution of the MTHFR C677T mutation to tHcy concentrations in children.     

Recent advances in the measurement of adiponectin isoform distribution

PURPOSE OF REVIEW: Adiponectin has potent antidiabetic and antiatherosclerotic actions. Recent studies in animals and humans suggest that the high-molecular weight adiponectin complex, consisting of many adiponectin monomers, is the biologically active form of the peptide. This article will present recent methodological approaches for analyzing adiponectin isoform distribution. RECENT FINDINGS: A handful of methods have been used for the isolation and measurement of high-molecular weight adiponectin, based on velocity gradient centrifugation, gel filtration chromatography and polyacrylamide gel electrophoresis. Recently, two novel sandwich enzyme-linked immuno-sorbent assays have been developed. The first makes use of antibodies raised against human high-molecular weight adiponectin and thus allows for the specific determination of high-molecular weight adiponectin in plasma. The second and more versatile enzyme-linked immuno-sorbent assay system enables the measurement of all adiponectin isoforms (i.e. low, middle and high-molecular weight) by means of selective digestion by proteases. SUMMARY: The development and commercial availability of novel enzyme-linked immuno-sorbent assay kits enables the easy and rapid measurement of high-molecular weight adiponectin in both research and clinical practice and will undoubtedly advance further our understanding of the role of adiponectin in health and disease.