Resistance to diet-induced adiposity in cannabinoid receptor-1 deficient mice is not due to impaired adipocyte function

Background: Overactivity and/or dysregulation of the endocannabinoid system (ECS) contribute to development of obesity. In vitro studies indicate a regulatory role for the cannabinoid receptor 1 (CB1) in adipocyte function and CB1-receptor deficient (CB1-/-) mice are resistant to high fat diet-induced obesity. Whether this phenotype of CB1-/- mice is related to altered fat metabolism in adipose tissue is unknown. Methods: We evaluated adipose tissue differentiation/proliferation markers and quantified lipogenic and lipolytic activities in fat tissues of CB1-/- and CB1+/+ mice fed a high-fat (HF) or a high-fat/fish oil (HF/FO) diet as compared to animals receiving a low-fat chow diet. Comparison between HF diet and HF/FO diet allowed to investigate the influence of dietary fat quality on adipose tissue biology in relation to CB1 functioning. Results: The adiposity-resistant phenotype of the CB1-/- mice was characterized by reduced fat mass and adipocyte size in HF and HF/FO-fed CB1-/- mice in parallel to a significant increase in energy expenditure as compared to CB1+/+ mice. The expression levels of adipocyte differentiation and proliferation markers were however maintained in these animals. Consistent with unaltered lipogenic gene expression, the fatty acid synthesis rates in adipose tissues from CB1-/- and CB1+/+ mice were unchanged. Whole-body and adipose-specific lipoprotein lipase (LPL) activities were also not altered in CB1-/- mice. Conclusions: These findings indicate that protection against diet-induced adiposity in CB1-deficient mice is not related to changes in adipocyte function per se, but rather results from increased energy dissipation by oxidative and non-oxidative pathways.

Consensus guidelines for the use and interpretation of angiogenesis assays

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference

The incidence of and risk factors for hyperglycemia and hypoglycemia in preterm infants receiving early-aggressive parenteral nutrition

Introduction: Optimizing nutritional support helps prevent extra uterine growth restriction and adverse long-term outcomes in preterm infants. Objectives: This study aimed to analyze the incidence of and risk factors for hyperglycemia and hypoglycemia in preterm infants receiving early-aggressive parenteral nutrition (PN). Methods: This prospective observational study included preterm infants receiving PN at the Neonatal Intensive Care Unit of Dr. Soetomo General Hospital between April 2018 and May 2019. Potential risk factors analyzed included asphyxia, sepsis, respiratory distress syndrome, multiple congenital anomalies, mortality, necrotizing enterocolitis, retinopathy of prematurity, the postoperative period, inotropic administration, glucose infusion rate (GIR) &gt; 10–12 mg/kg/min, GIR 4–&lt;5.5 mg/kg/min, and increase in GIR &lt;1 mg/kg/min. Results: Of the 105 preterm infants included, hyperglycemia and hypoglycemia were found in 14 (13.3%) and 26 (24.8%) infants, respectively, with most incidents occurring in the first week (hyperglycemia: 85.7%; hypoglycemia: 88.5%). Sepsis was an independent risk factor for hyperglycemia (odds ratio [OR]: 8.743, 95% confidence interval [CI]: 2.392–31.959; P = 0.001). Hypoglycemia independent risk factors included the postoperative period (OR: 4.425, 95% CI: 1.218–16.073; P = 0.024) and use of GIR 4–&lt;5.5 mg/kg/min (OR: 2.950, 95% CI: 1.035–8.405; P = 0.043). Conclusion: Hyperglycemia and hypoglycemia can occur in preterm infants receiving early-aggressive PN; most cases occur within the first week of life. Hypoglycemia correlated with low glucose intake, and hyperglycemia correlated with sepsis. Monitoring blood glucose levels in preterm infants receiving PN, especially in the first weeks of life, may decrease morbidity associated with hyperglycemia or hypoglycemia.</p

Short-term growth and substrate use in very-low-birth-weight infants fed formulas with different energy contents

Background: Currently available preterm formulas with energy contents of 3350 kJ (800 kcal)/L promote weight and length gain at rates at or above intrauterine growth rates but disproportionately increase total body fat. Objective: The objective of this study was to determine whether fat accretion in formula-fed, very-low-birth-weight (VLBW) infants could be decreased and net protein gain maintained by reducing energy intakes from 502 kJ (XO kcal).kg(-1).d(-1) [normal-energy (NE) formula] to 419 kJ (100 kcal).kg(-1).d(-1) [low-energy (LE) formula] while providing similar protein intakes (3.3 g.kg(-1).d(-1)). Design: The study was a randomized, controlled trial enrolling 20 oppropriate-for-gestational-age (AGA) and 16 small-for-gestational-age (SGA) VLBW infants (mean birth weight: 1.1 kg; mean gestational age: 31 wk); energy expenditure and nutrient balance were measured at 4 wk of age and anthropometric measurements were made when infants weighed 2 kg. Results: The percentage of fat in newly formed tissue was significantly lower in AGA infants fed the LE formula (n = 9) than in those fed the NE formula (n = 10) (9% compared with 23%; analysis of variance, P = 0.001). Energy expenditure was higher in AGA infants fed the NE formula than in those fed the LE formula. Skinfold thickness was markedly lower in AGA infants fed the LE formula than in those fed the NE formula, resulting in a lower estimated percentage body fat (8.0 +/- 1.9% and 10.8 +/- 3.5%, respectively; P <0.05). Three of 6 SGA infants fed the LE formula were excluded during the study because of poor weight gain. Conclusions: Body composition can easily be altered by changing the energy intakes of formula-fed VLBW infants. Energy intakes in these infants should be >419 kJ (100 kcal).kg(-1).d(-1)

Twelve weeks of moderate aerobic exercise without dietary intervention or weight loss does not affect 24-h energy expenditure in lean and obese adolescents1234

Background: Exercise might have a persistent effect on energy expenditure and fat oxidation, resulting in increased fat loss. However, even without weight loss, exercise results in positive metabolic effects. The effect of an aerobic exercise program on 24-h total energy expenditure (TEE) and its components—basal (BEE), sleep (SEE), and awake sedentary (SEDEE) energy expenditure and substrate oxidation—has not been studied in lean and obese adolescents

Influence of common variants near INSIG2, in FTO, and near MC4R genes on overweight and the metabolic profile in adolescence: the TRAILS (TRacking Adolescents' Individual Lives Survey) Study

Background: Overweight is a complex trait in which both environmental and genetic factors play a role. Objective: We aimed to evaluate the influence of common genetic variants identified by genome-wide association studies on overweight and the metabolic profile in adolescence. Design: In a population-based cohort of 663 girls and 612 boys aged 16 y, weight, height, skinfold thicknesses, percentage body fat, waist circumference, blood pressure, glucose, insulin, lipid profile, and DNA were obtained. We defined overweight according to international criteria. We performed multiple linear and logistic regression analyses to assess the influence of candidate single nucleotide polymorphisms near the INSIG2, in the FTO, and near the MC4R genes and repeated-measures analyses of available body mass index (BMI) and skinfold thickness data across 3 visits at ages 11, 13.5, and 16 y. Results: A total of 15.1% of participants were overweight or obese at age 16 y. No associations with INSIG2 were found. Common variation in the FTO gene was associated with sex-specific z scores of BMI (B: 0.11; 95% CI: 0.03, 0.19), sum of skinfold thicknesses (B: 0.12; 95 % CI: 0.04, 0.20), percentage body fat (B: 0.11; 95 % CI: 0.03, 0.19), waist circumference (B: 0.11; 95% CI: 0.03, 0.19), fasting glucose (B: 0.10; 95% CI: 0.00, 0.20), and overweight (odds ratio: 1.34; 95% CL 1.06, 1.69) at age 16 y. Repeated-measures analyses confirmed the associations for BMI and sum of skinfold thicknesses, and physical activity did not modify these associations. Common variation near the MC4R gene was associated with BMI in cross-sectional (B: 0.11; 95% Cl: 0.02, 0.20) and repeated-measures (13: 0.12; 95% Cl: 0.03, 0.20) analyses. Conclusions: Common variation in the FTO gene is associated with overall and abdominal adiposity. Variation near the MC4R gene is associated with BMI. These findings in adolescents strengthen and extend the results from previous research. Am J Clin Nutr 2010;91:321-8