Circulating irisin levels are positively associated with metabolic risk factors in sedentary subjects.

Introduction: A physically active life-style plays an independent role in the protection against type 2 diabetes and cardiovascular diseases. Irisin, a novel exercise-induced myokine, activates thermogenesis in rodents through increasing beige fat cells abundance within white fat. We aimed to investigate circulating irisin levels in association with the degree of physical activity and various metabolic parameters in humans.

Parathyroid Hormone-Related Protein, Human Adipose-Derived Stem Cells Adipogenic Capacity and Healthy Obesity.

Objective: This study aimed to define the potential role of PTHrP on adipogenic regulation and to analyze its relationship with obesity and insulin resistance.

Design: This was a cross-sectional study in which visceral (VAT) and subcutaneous (SAT) adipose tissue were extracted from 19 morbidly obese, 10 obese, and 10 lean subjects. PTHrP mRNA levels were measured in VAT and SAT.

Effects of biliopancreatic diversion on diurnal leptin, insulin and free fatty acid levels.

Background: Free fatty acid (FFA) levels are raised in obesity as a consequence of increased production and reduced clearance. They may link obesity with insulin resistance. Bariatric surgery can result in considerable weight loss and reduced insulin resistance, but the mechanism of action is not well understood.

Serum 25-hydroxyvitamin D and adipose tissue vitamin D receptor gene expression: relationship with obesity and type 2 diabetes.

Context: The relationship between 25-hydroxyvitamin D [25(OH)D] and obesity and type 2 diabetes is not completely understood. Vitamin D receptor (VDR) expression in adipose tissue (AT) is related to obesity and might be regulated by 1,25-dihydroxyvitamin D3 [1,25(OH)2D3].

Objective: To analyze serum 25(OH)D and VDR gene expression in AT according to body mass index (BMI) and glycemic status and the effect of 1,25(OH)2D3 on AT according to BMI.

DBC1 is involved in adipocyte inflammation and is a possible marker of human adipose tissue senescence.

Objective: To investigate the possible role of deleted in breast cancer 1 (DBC1) in adipocyte and adipose tissue inflammation.

Methods: In vitro knockdown experiments using shRNA-lentiviral particles were performed to investigate the effect of DBC1 on adipocyte inflammation, sirtuin 1 (Sirt1) activity, and the AMPK pathway. The relationship between DBC1 and inflammation in human adipose tissue also was examined in two independent cohorts.

PRDM16 sustains white fat gene expression profile in human adipocytes in direct relation with insulin action.

In the present study, we aimed to evaluate the possible role of PRDM16 in human adipocytes and in whole adipose tissue according to obesity and insulin sensitivity. PRDM16 knockdown (KD) had a dual behavior. While KD in preadipocytes led to enhanced gene expression markers of adipocyte differentiation, PRDM16 KD in fully differentiated adipocytes resulted in decreased adipogenic gene expression and insulin action.

Deleted in breast cancer 1 plays a functional role in adipocyte differentiation.

Genetic deletion of Dbc1 in mice reduced adipose tissue senescence and inflammation while promoting an expansion of this tissue. Here, we aimed to investigate DBC1 mRNA and protein levels in human adipose tissue from subjects with a wide spectrum of fat mass (cohort 1; n = 105) and insulin resistance (cohort 2; n = 47); we also investigated the effects of DBC1 knockdown on 3T3-L1 adipocyte differentiation. DBC1 mRNA was relatively abundant in both visceral (VAT) and subcutaneous adipose tissue (SAT) (mainly in the adipocyte fraction), being decreased in adipose tissue from obese compared with lean subjects.

Cytosolic aconitase activity sustains adipogenic capacity of adipose tissue connecting iron metabolism and adipogenesis.

To gain insight into the regulation of intracellular iron homeostasis in adipose tissue, we investigated the role of iron regulatory protein 1/cytosolic aconitase 1 (ACO1). ACO1 gene expression and activity increased in parallel to expression of adipogenic genes during differentiation of both murine 3T3-L1 cells and human preadipocytes. Lentiviral knockdown (KD) of Aco1 in 3T3-L1 preadipocytes led to diminished cytosolic aconitase activity and isocitrate dehydrogenase 1 (NADP(+)), soluble (Idh1) mRNA levels, decreased intracellular NADPH:NADP ratio, and impaired adipogenesis during adipocyte differentiation.

Nonalcoholic fatty liver disease and age are strong indicators for atherosclerosis in morbid obesity.

Objective: Whether nonalcoholic fatty liver disease (NAFLD) can predict atherosclerosis in obese patients remains unclear. The aim of our study was to investigate the usefulness of NAFLD and other cardiometabolic parameters in predicting subclinical atherosclerosis in obese patients.

Design, Patients And Measurements: We studied 314 consecutive obese subjects (223 women; mean age, 45·04 ± 9·34 years; body mass index 44·3 ± 5 kg/m(2) ) and 47 healthy lean individuals.

Coxsackie and adenovirus receptor is increased in adipose tissue of obese subjects: a role for adenovirus infection?

Context: The coxsackie and adenovirus receptor (CAR) was originally identified as a common receptor for coxsackie B viruses and type C adenoviruses.

Objective: The objective was to investigate CAR gene expression in human adipose tissue to explore its associations with adipocyte physiology.

Design And Setting: This was an ex vivo study in 91 visceral adipose tissue (VAT) and 109 sc adipose tissue (SAT) human samples (61 paired) obtained during elective surgical procedures.

Carotid pulse wave velocity by magnetic resonance imaging is increased in middle-aged subjects with the metabolic syndrome.

Arterial pulse wave velocity (PWV), an independent predictor of cardiovascular disease, physiologically increases with age; however, growing evidence suggests metabolic syndrome (MetS) accelerates this increase. Magnetic resonance imaging (MRI) enables reliable noninvasive assessment of arterial stiffness by measuring arterial PWV in specific vascular segments. We investigated the association between the presence of MetS and its components with carotid PWV (cPWV) in asymptomatic subjects without diabetes.

Hypothalamic damage is associated with inflammatory markers and worse cognitive performance in obese subjects.

Context: Growing evidence implicates hypothalamic inflammation in the pathogenesis of diet-induced obesity and cognitive dysfunction in rodent models. Few studies have addressed the association between obesity and hypothalamic damage in humans and its relevance.

Objective: This study aimed to determine markers of obesity-associated hypothalamic damage on diffusion tensor imaging (DTI) and to determine whether DTI metrics are associated with performance on cognitive testing.

Adipocyte pseudohypoxia suppresses lipolysis and facilitates benign adipose tissue expansion.

Prolyl hydroxylase enzymes (PHDs) sense cellular oxygen upstream of hypoxia-inducible factor (HIF) signaling, leading to HIF degradation in normoxic conditions. In this study, we demonstrate that adipose PHD2 inhibition plays a key role in the suppression of adipocyte lipolysis. Adipose Phd2 gene ablation in mice enhanced adiposity, with a parallel increase in adipose vascularization associated with reduced circulating nonesterified fatty acid levels and normal glucose homeostasis.

Transducin-like enhancer of split 3 (TLE3) in adipose tissue is increased in situations characterized by decreased PPARγ gene expression.

Unlabelled: Transgenic overexpression of adipose tissue (AT) transducin-like enhancer of split 3 (TLE3) mimicked peroxisome proliferator-activated receptor gamma (PPARγ) agonists, improving insulin resistance in mice. This study aimed to investigate TLE3 gene expression (qRT-PCR) and protein (Western blot) in subjects with a wide spectrum of obesity and insulin sensitivity and in an independent cohort of obese subjects following surgery-induced weight loss. TLE3 was analyzed in human adipocytes and after treatment with rosiglitazone.

Brain iron overload, insulin resistance, and cognitive performance in obese subjects: a preliminary MRI case-control study.

Objective: The linkage among the tissue iron stores, insulin resistance (IR), and cognition remains unclear in the obese population. We aimed to identify the factors that contribute to increased hepatic iron concentration (HIC) and brain iron overload (BIO), as evaluated by MRI, and to evaluate their impact on cognitive performance in obese and nonobese subjects.

Research Design And Methods: We prospectively recruited 23 middle-aged obese subjects without diabetes (13 women; age 50.

Moderate-vigorous physical activity across body mass index in females: moderating effect of endocannabinoids and temperament.

Background: Endocannabinoids and temperament traits have been linked to both physical activity and body mass index (BMI) however no study has explored how these factors interact in females. The aims of this cross-sectional study were to 1) examine differences among distinct BMI groups on daytime physical activity and time spent in moderate-vigorous physical activity (MVPA), temperament traits and plasma endocannabinoid concentrations; and 2) explore the association and interaction between MVPA, temperament, endocannabinoids and BMI.

Methods: Physical activity was measured with the wrist-worn accelerometer Actiwatch AW7, in a sample of 189 female participants (43 morbid obese, 30 obese, and 116 healthy-weight controls).

Adipose tissue μ-crystallin is a thyroid hormone-binding protein associated with systemic insulin sensitivity.

Background: Circulating thyroid hormones have been described to be intrinsically associated with insulin sensitivity in healthy subjects. μ-Crystallin is a nicotinamide adenine dinucleotide phosphate-dependent thyroid hormone-binding protein that has been shown to bind T3 in the cytoplasm. We aimed to study μ-Crystallin expression in adipose tissue and in muscle in association with insulin action and thyroid function.

Fine-tuned iron availability is essential to achieve optimal adipocyte differentiation and mitochondrial biogenesis.

Aims/hypothesis: Adipose tissue from obese and insulin-resistant individuals showed altered expression of several iron-related genes in a recent study, suggesting that iron might have an important role in adipogenesis. To investigate this possible role, we aimed to characterise the effects of iron on adipocyte differentiation.

Methods: Intracellular iron deficiency was achieved using two independent approaches: deferoxamine administration (20 and 100 μmol/l) and transferrin knockdown (TF KD).

Placental sprouty 2 (SPRY2): relation to placental growth and maternal metabolic status.

Background: SPROUTY2 (SPRY2) is a membrane-associated protein expressed by placental macrophages with regulatory roles in tissue growth and development. The SPRY2 locus was shown to be associated with body fat distribution and susceptibility to type 2 diabetes.

Objectives: We assessed whether SPRY2 mRNA levels are related with maternal metabolic status and with placental weight.

Circulating irisin levels and coronary heart disease: association with future acute coronary syndrome and major adverse cardiovascular events.

Introduction: Irisin is a newly discovered myokine, associated with 'browning' of the white adipose tissue, obesity, insulin resistance and metabolic syndrome. The purpose of this study is to evaluate circulating irisin as a predictor of acute coronary syndromes (ACSs) and major adverse cardiovascular events (MACE).

Methods: Sub-study 1: a case-control study, nested within the Veteran's Affairs Normative Ageing Study, evaluating circulating irisin levels in 88 ACS cases and 158 age- and sampling year-matched controls, as a predictor of ACS.

Olive oil phenolic compounds decrease the postprandial inflammatory response by reducing postprandial plasma lipopolysaccharide levels.

We investigated the molecular mechanisms by which phenolic compounds (phenols) in virgin olive oil reduce the postprandial inflammatory response with the aim of identifying the transcription factor involved and the downstream effects. Olive oil-based breakfasts prepared with virgin olive oil (VOO) with high (398 ppm), intermediate (149 ppm) and low (70 ppm) phenol content were administered to 49 metabolic syndrome patients following a randomized crossover design. The consumption of a high-phenol VOO-based breakfast limited the increase of lipopolysaccharide plasma levels, TLR4, and SOCS3 proteins (p<0.

Association of irisin with fat mass, resting energy expenditure, and daily activity in conditions of extreme body mass index.

FNDC5/irisin has been recently postulated as beneficial in the treatment of obesity and diabetes because it is induced in muscle by exercise, increasing energy expenditure. However, recent reports have shown that WAT also secretes irisin and that circulating irisin is elevated in obese subjects. The aim of this study was to evaluate irisin levels in conditions of extreme BMI and its correlation with basal metabolism and daily activity.