OBJECTIVETo investigate activation of brown adipose tissue (BAT) stimulated by medium-chain triglyceride (MCT).

METHODS30 Male C57BL/6J obese mice induced by fed high fat diet (HFD) were divided into 2 groups, and fed another HFD with 2% MCT or long-chain triglyceride (LCT) respectively for 12 weeks. Body weight, blood biochemical variables, interscapular brown fat tissue (IBAT) mass, expressions of mRNA and protein of beta 3-adrenergic receptors (β3-AR), uncoupling protein-1 (UCP1), hormone sensitive lipase (HSL), protein kinase A (PKA), and adipose triglyceride lipase (ATGL) in IBAT were measured.

RESULTSSignificant decrease in body weight and body fat mass was observed in MCT group as compared with LCT group (P<0.05) after 12 weeks. Greater increases in IBAT mass was observed in MCT group than in LCT group (P<0.05). Blood TG, TC, LDL-C in MCT group were decreased significantly, meanwhile blood HDL-C, ratio of HDL-C/LDL-C and norepinephrine were increased markedly. Expressions of mRNA and protein of β3-AR, UCP1, PKA, HSL, ATGL in BAT were greater in MCT group than in LCT group (P<0.05).

CONCLUSIONOur results suggest that MCT stimulated the activation of BAT, possible via norepinephrine pathway, which might partially contribute to reduction of the body fat mass in obese mice fed high fat diet.

Adipose Tissue, Brown ; drug effects ; Adiposity ; drug effects ; Animals ; Dietary Fats ; administration & dosage ; pharmacology ; Ion Channels ; genetics ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mitochondrial Proteins ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Triglycerides ; chemistry ; pharmacology ; Uncoupling Protein 1 ; Weight Loss

Androgen deprivation in men leads to increased adiposity, but the mechanisms underlying androgen regulation of fat mass have not been fully defined. Androgen receptor (AR) is expressed in monocytes/macrophages, which are resident in key metabolic tissues and influence energy metabolism in surrounding cells. Male mice bearing a cell-specific knockout of the AR in monocytes/macrophages (M-ARKO) were generated to determine whether selective loss of androgen signaling in these cells would lead to altered body composition. Wild-type (WT) and M-ARKO mice (12-22 weeks of age, n = 12 per group) were maintained on a regular chow diet for 8 weeks and then switched to a high-fat diet for 8 additional weeks. At baseline and on both the regular chow and high-fat diets, no differences in lean mass or fat mass were observed between groups. Consistent with the absence of differential body weight or adiposity, no differences in food intake (3.0 ± 0.5 g per day for WT mice vs 2.8 ± 0.4 g per day for M-ARKO mice) or total energy expenditure (0.6 ± 0.1 Kcal h^-1 for WT mice vs 0.5 ± 0.1 Kcal h^-1 for M-ARKO mice) were evident between groups during high-fat feeding. Liver weight was greater in M-ARKO than that in WT mice (1.5 ± 0.1 g vs 1.3 ± 0.0 g, respectively, P = 0.02). Finally, M-ARKO mice did not exhibit impairments in glucose tolerance or insulin sensitivity relative to WT mice at any study time point. In aggregate, these findings suggest that AR signaling specifically in monocytes/macrophages does not contribute to the regulation of systemic energy balance, adiposity, or insulin sensitivity in male mice.
Adiposity/genetics* ; Animals ; Blood Glucose/metabolism* ; Energy Metabolism/genetics* ; Glucose Tolerance Test ; Homeostasis/genetics* ; Liver/anatomy & histology* ; Macrophages/metabolism* ; Male ; Mice ; Mice, Knockout ; Monocytes/metabolism* ; Organ Size ; Receptors, Androgen/metabolism* ; Signal Transduction

Because of their physiological similarity to humans, pigs provide an excellent model for the study of obesity. This study evaluated diet-induced adiposity in genetically lean pigs and found that body weight and energy intake did not differ between controls and pigs fed the high-fat (HF) diet for three months. However, fat mass percentage, adipocyte size, concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), insulin, and leptin in plasma were significantly higher in HF pigs than in controls. The HF diet increased the expression in backfat tissue of genes responsible for cholesterol synthesis such as Insig-1 and Insig-2. Lipid metabolism-related genes including sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthase 1 (FASN1), diacylglycerol O-acyltransferase 2 (DGAT2), and fatty acid binding protein 4 (FABP4) were significantly up-regulated in backfat tissue, while the expression of proliferator-activated receptor-α (PPAR-α) and carnitine palmitoyl transferase 2 (CPT2), both involved in fatty acid oxidation, was reduced. In liver tissue, HF feeding significantly elevated the expression of SREBP-1c, FASN1, DGAT2, and hepatocyte nuclear factor-4α (HNF-4α) mRNAs. Microarray analysis further showed that the HF diet had a significant effect on the expression of 576 genes. Among these, 108 genes were related to 21 pathways, with 20 genes involved in adiposity deposition and 26 related to immune response. Our results suggest that an HF diet can induce genetically lean pigs into obesity with body fat mass expansion and adipose-related inflammation.
Adipocytes/cytology* ; Adipogenesis/genetics* ; Adipose Tissue/metabolism* ; Adiposity ; Animals ; Body Weight ; Cholesterol/blood* ; Cholesterol, HDL/blood* ; Cholesterol, LDL/blood* ; Diet, High-Fat ; Inflammation/genetics* ; Insulin/blood* ; Leptin/blood* ; Lipid Metabolism ; Male ; Obesity/genetics* ; Random Allocation ; Swine ; Triglycerides/blood*

OBJECTIVETo investigate the effect of immunization with prokaryotically expressed recombinant fusion protein of extracellular near-transmembrane domain of Tibet minipig leptin receptor (OBR) on fat deposition in SD rats.

METHODSA pair of specific primers containing BamHI and HindIII restriction enzyme sites was designed to amplify the extracellular near-transmembrane domain (1705-2364 bp) of Tibet minipig OBR gene. After digestion, the amplified fragment was inserted into the plasmid pRSETA between BamHI and HindIII sites. The recombinant plasmid was transformed and expressed in E.coli BL21(DE3) and the product was analyzed by SDS-PAGE and Western blotting. SD rats were immunized with the fusion protein, and the changes in body weight, feed intake, body length, Lee's index, percentage of abdominal fat, liver fat deposition and subcutaneous fat deposition were assessed.

RESULTSThe recombinant fusion protein obtained (about 27.6 kD) was expressed in E.coli induced by IPTG and identified by SDS-PAGE and Western blotting. The rats immunized with the fusion protein showed no significant changes in body weight, body length, Lee's index, percentage of abdominal fat or liver fat deposition as compared with the control rats. Nevertheless, the immunization caused significantly increased feed intake and significantly decreased volume of subcutaneous fat cells.

CONCLUSIONImmunization with the fusion protein of extracellular near-transmembrane domain of Tibet minipig OBR can promote feed intake and suppress subcutaneous fat deposition in SD rats.

Adiposity ; drug effects ; Animals ; Base Sequence ; Female ; Gene Expression ; Genetic Vectors ; Obesity ; Plasmids ; Rats ; Rats, Sprague-Dawley ; Receptors, Leptin ; administration & dosage ; genetics ; Recombinant Fusion Proteins ; administration & dosage ; genetics ; Subcutaneous Fat ; physiology ; Swine ; Swine, Miniature

Adiposity ; drug effects ; Animals ; Diethylhexyl Phthalate ; toxicity ; Female ; Gene Expression Regulation, Developmental ; drug effects ; Male ; Maternal Exposure ; Metabolic Diseases ; chemically induced ; PPAR gamma ; genetics ; metabolism ; Pregnancy ; Prenatal Exposure Delayed Effects ; Rats ; Rats, Sprague-Dawley

Obesity is recognized as a chronic low-grade inflammatory state due to adipose tissue expansion being accompanied by an increase in the production of proinflammatory adipokines. Our group is the first to report that B-cell-activating factor (BAFF) is produced from adipocytes and functions as a proinflammatory adipokine. Here, we investigated how loss of BAFF influenced diet-induced obesity in mice by challenging BAFF-/- mice with a high-fat diet for 10 weeks. The results demonstrated that weight gain in BAFF-/- mice was >30% than in control mice, with a specific increase in the fat mass of the subcutaneous region rather than the abdominal region. Expression of lipogenic genes was examined by quantitative real-time PCR, and increased lipogenesis was observed in the subcutaneous adipose tissue (SAT), whereas lipogenesis in the epididymal adipose tissue (EAT) was reduced. A significant decrease in EAT mass resulted in the downregulation of inflammatory gene expression in EAT, and more importantly, overall levels of inflammatory cytokines in the circulation were reduced in obese BAFF-/- mice. We also observed that the macrophages recruited in the enlarged SAT were predominantly M2 macrophages. 3T3-L1 adipocytes were cultured with adipose tissue conditioned media (ATCM), demonstrating that EAT ATCM from BAFF-/- mice contains antilipogenic and anti-inflammatory properties. Taken together, BAFF-/- improved systemic inflammation by redistributing adipose tissue into subcutaneous regions. Understanding the mechanisms by which BAFF regulates obesity in a tissue-specific manner would provide therapeutic opportunities to target obesity-related chronic diseases.
3T3-L1 Cells ; Adipocytes/drug effects/metabolism ; Adiposity/*genetics ; Animals ; B-Cell Activating Factor/*genetics ; Cells, Cultured ; Culture Media, Conditioned/pharmacology ; Diet, High-Fat ; Disease Models, Animal ; Gene Knockout Techniques ; Inflammation/*genetics ; Lipogenesis/genetics ; Macrophages/metabolism ; Male ; Mice ; Mice, Knockout ; Obesity/*etiology

OBJECTIVETo investigate the antiobesity effect of Jueming Prescription (JMP), a Chinese herbal medicine formula, and its influence on mRNA expressions of beta3 adrenergic receptor (beta3-AR) and uncoupling protein-2 (UCP-2) in adipose tissue of diet-induced obese rats.

METHODSFifty male Sprague-Dawley rats were randomly divided into the normal control group (n =8) that was on a standard chow diet, and the obese model group (n =42) that was on a diet of high fat chow. Two weeks after the high fat diet, 29 obese rats in the obese model group were further randomly divided into 3 groups: the untreated obese model group (n =9), the metformin group (n =10, metformin 300 mg kg⁻¹ day)⁻¹, and the JMP group (n =10, JMP 4 g kg⁻¹ day⁻¹). After 8-week treatment, body weight, wet weight of visceral fat, and percentage of body fat (PBF) were measured. The levels of fasting blood glucose, serum lipids, and insulin were assessed, and insulin sensitivity index (ISI) was calculated. The adipose tissue section was stained with hematoxylin-Eosin, and the cellular diameter and quantity of adipocytes were evaluated by light microscopy. The mRNA expressions of beta3-AR and UCP-2 from the peri-renal fat tissue were determined by real-time reverse transcription polymerase chain reaction (RT-PCR).

RESULTSCompared with the obese model group, treatment with JMP resulted in significantly lower body weight, wet weight of visceral fat, PBF, and diameter of adipocytes, and significantly higher level of high-density lipoprotein cholesterol, ISI (all P<0.01), JMP increased the mRNA expressions of beta3-AR and UCP-2 from perirenal fat tissue (P <0.05, P<0.01).

CONCLUSIONSJMP could reduce body weight and adipocyte size; and the effect was associated with the up-regulation of beta3-AR and UCP-2 expressions in the adipose tissue and improvement of insulin sensitivity.

Adipocytes ; drug effects ; metabolism ; pathology ; Adiposity ; drug effects ; Animals ; Blood Glucose ; metabolism ; Body Weight ; drug effects ; Cell Size ; drug effects ; Diet, High-Fat ; Drugs, Chinese Herbal ; pharmacology ; Epididymis ; drug effects ; pathology ; Fasting ; blood ; Gene Expression Regulation ; drug effects ; Insulin ; blood ; Intra-Abdominal Fat ; drug effects ; metabolism ; pathology ; Ion Channels ; genetics ; metabolism ; Lipids ; blood ; Male ; Mitochondrial Proteins ; genetics ; metabolism ; Obesity ; blood ; genetics ; pathology ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, Adrenergic, beta-3 ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Uncoupling Protein 2 ; Weight Loss ; drug effects