No abstract available.
Adipocytes, Brown* ; Diet, High-Fat*

No abstract available.
Adipocytes, Brown* ; Diet, High-Fat*

Brown adipose tissue contributes to energy balance in humans by generating heat via the mitochondrial uncoupling of lipid oxidation. Currently it is believed that brown adipose has two origins: Myf5-negative progenitor (its source is same as that of white adipocyte) and Myf5-positive progenitor (its source is same as myocyte). Due to the different origins of brown adipocytes, they may be formed via multiple pathways which include the main pathway (by which Myf5-positive progenitors differentiate into brown adipocytes that distribute in classical locations) and alternative pathway (by which Myf5-negative progenitors differentiate into brown adipocytes that distribute in white adipose tissue).
Adipocytes ; cytology ; Adipose Tissue, Brown ; cytology ; physiology ; Humans

BACKGROUND: Brown adipocytes have thermogenic characteristics in neonates and elicit anti-inflammatory responses. We postulated that thermogenic brown adipocytes produce distinctive intercellular effects in a hypobaric state. The purpose of this study is to analyze the correlation between brown adipocyte and regulatory T cell (T(reg)) expression under intermittent hypobaric conditions. METHODS: Brown and white adipocytes were harvested from the interscapular and flank areas of C57BL6 mice, respectively. Adipocytes were cultured with syngeneic splenocytes after isolation and differentiation. Intermittent hypobaric conditions were generated using cyclic negative pressure application for 48 h in both groups of adipocytes. Expression levels of T(regs) (CD4 + CD25 + Foxp3 + T cells), cytokines [tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10), and the programmed death-ligand 1 (PD-L1)] co-inhibitory ligand were examined. RESULTS: Splenocytes, cultured with brown and white adipocytes, exhibited comparable T(reg) expression in a normobaric state. Under hypobaric conditions, brown adipocytes maintained a subset of T(regs). However, a decrease in T(regs) was found in the white adipocyte group. TNF-α levels increased in both groups under hypobaric conditions. In the brown adipocyte group, anti-inflammatory IL-10 expression increased significantly; meanwhile, IL-10 expression decreased in the white adipocyte group. PD-L1 levels increased more significantly in brown adipocytes than in white adipocytes under hypobaric conditions. CONCLUSION: Both brown and white adipocytes support T(reg) expression when they are cultured with splenocytes. Of note, brown adipocytes maintained T(reg) expression in intermittent hypobaric conditions. Anti-inflammatory cytokines and co-inhibitory ligands mediate the immunomodulatory effects of brown adipocytes under altered atmospheric conditions. Brown adipocytes showed the feasibility as a source of adjustment in physical stresses.
Adipocytes ; Adipocytes, Brown ; Adipocytes, White ; Animals ; Coculture Techniques ; Cytokines ; Humans ; Infant, Newborn ; Interleukin-10 ; Ligands ; Mice ; Necrosis

Brown adipose tissue (BAT) is a specialized thermoregulatory organ that has a critical role in the regulation of energy metabolism. Specifically, energy expenditure can be enhanced by the activation of BAT function and the induction of a BAT-like catabolic phenotype in white adipose tissue (WAT). Since the recent recognition of metabolically active BAT in adult humans, BAT has been extensively studied as one of the most promising targets identified for treating obesity and its related disorders. In this review, we summarize information on the developmental origin of BAT and the progenitors of brown adipocytes in WAT. We explore the transcriptional control of brown adipocyte differentiation during classical BAT development and in WAT browning. We also discuss the neuronal control of BAT activity and summarize the recently identified non-canonical stimulators of BAT that can act independently of beta-adrenergic stimulation. Finally, we review new findings on the beneficial effects of BAT activation and development with respect to improving metabolic profiles. We highlight the therapeutic potential of BAT and its future prospects, including pharmacological intervention and cell-based therapies designed to enhance BAT activity and development.
Adipocytes/cytology/metabolism ; Adipogenesis ; Adipose Tissue, Brown/cytology/metabolism/*physiology ; Animals ; Humans ; Obesity/therapy

Brown adipose tissue (BAT) is regarded as a key target for developing interventions to prevent and treat obesity and age-related diseases. In addition, uncoupling pro tein 1 (UCP1)
Adipocytes ; Adipose Tissue ; Adipose Tissue, Brown ; Adipose Tissue, White ; Atrophy ; Eating ; Humans ; Middle Aged ; Obesity ; Thermogenesis

The induction of brown-like adipocyte development in white adipose tissue (WAT) confers numerous metabolic benefits by decreasing adiposity and increasing energy expenditure. Therefore, WAT browning has gained considerable attention for its potential to reverse obesity and its associated co-morbidities. However, this perspective has been tainted by recent studies identifying the detrimental effects of inducing WAT browning. This review aims to highlight the adverse outcomes of both overactive and underactive browning activity, the harmful side effects of browning agents, as well as the molecular brake-switch system that has been proposed to regulate this process. Developing novel strategies that both sustain the metabolic improvements of WAT browning and attenuate the related adverse side effects is therefore essential for unlocking the therapeutic potential of browning agents in the treatment of metabolic diseases.
Adipocytes, Beige ; cytology ; Adipose Tissue, Brown ; cytology ; metabolism ; Adipose Tissue, White ; cytology ; Aging ; metabolism ; Animals ; Humans

Hibernoma is a rare, benign adipose tumor composed of brown fat cells with eosinophilic granular or multivacuolated cytoplasm. The cytologic features of hibernoma have been rarely reported and may mimic other polygonal cell neoplasms. We report the imprint cytologic features of a case of hibernoma in the left thigh of a 68-year-old woman. Microscopic examination showed large, round, or polygonal brown fat cells. The cells were arranged in fragments or clusters. The nuclei were uniformly round with finely granular chromatin. The cytoplasm was multivacuolated or univacuolated. The abundant eosinophilic granular cytoplasm was also present. No nuclear atypia were present. Immunohistochemical staining showed that cells were positive for S-100 protein.
Adipocytes, Brown ; Aged ; Chromatin ; Cytoplasm ; Eosinophils ; Female ; Humans ; Hydrazines ; Lipoma ; S100 Proteins ; Thigh

Rheumatoid arthritis (RA) is a systemic autoimmune disease involving excessive inflammation. Recently, RA associated with a metabolic disorder was revealed to be non-responsive to RA medications. Metformin has been reported to have a therapeutic effect on RA and obesity. The aim of this investigation was to study the therapeutic effect and the underlying mechanism of metformin's action in an experimental model of collagen-induced arthritis (CIA) associated with obesity. Metformin was administered daily for 13 weeks to mice with CIA that had been fed a high-fat diet. Metformin ameliorated the development of CIA in obese mice by reducing autoantibody expression and joint inflammation. Furthermore, metformin decreased the expression levels of pSTAT3 and pmTOR and had a small normalizing effect on the metabolic profile of obese CIA mice. In addition, metformin increased the production of pAMPK and FGF21. Metformin also induced the differentiation of brown adipose tissue (BAT), which led to a reciprocal balance between T helper (Th) 17 and regulatory T (Treg) cells in vitro and in vivo. These results suggest that metformin can dampen the development of CIA in obese mice and reduce metabolic dysfunction by inducing BAT differentiation. Thus, metformin could be a therapeutic candidate for non-responsive RA.
Adipocytes, Brown ; Adipose Tissue, Brown ; Animals ; Arthritis ; Arthritis, Experimental ; Arthritis, Rheumatoid ; Autoimmune Diseases ; Diet, High-Fat ; In Vitro Techniques ; Inflammation ; Joints ; Metabolome ; Metformin ; Mice ; Mice, Obese ; Models, Theoretical ; Obesity

BACKGROUND: Resveratrol (RSV) is a polyphenolic phytoalexin that has many effects on metabolic diseases such as diabetes and obesity. Given the importance of brown adipose tissue (BAT) for energy expenditure, we investigated the effects of RSV on brown adipocytes. METHODS: For the in vitro study, interscapular BAT was isolated from 7-week-old male Sprague Dawley rats. For the in vivo study, 7-week-old male Otsuka Long Evans Tokushima Fatty (OLETF) rats were divided into four groups and treated for 27 weeks with: standard diet (SD); SD+RSV (10 mg/kg body weight, daily); high fat diet (HFD); HFD+RSV. RSV was provided via oral gavage once daily during the in vivo experiments. RESULTS: RSV treatment of primary cultured brown preadipocytes promoted mitochondrial activity, along with over-expression of estrogen receptor α (ER-α). In OLETF rats, both HFD and RSV treatment increased the weight of BAT and the differentiation of BAT. However, only RSV increased the mitochondrial activity and ER-α expression of BAT in the HFD-fed group. Finally, RSV improved the insulin sensitivity of OLETF rats by increasing the mitochondrial activity of BAT, despite having no effects on white adipocytes and muscles in either diet group. CONCLUSION: RSV could improve insulin resistance, which might be associated with mitochondrial activity of brown adipocyte. Further studies evaluating the activity of RSV for both the differentiation and mitochondrial activity of BAT could be helpful in investigating the effects of RSV on metabolic parameters.
Adipocytes, Brown* ; Adipocytes, White ; Adipose Tissue, Brown ; Animals ; Body Weight ; Diet ; Diet, High-Fat* ; Energy Metabolism ; Estrogen Receptor alpha ; Estrogens ; Humans ; In Vitro Techniques ; Insulin Resistance ; Male ; Metabolic Diseases ; Mitochondria ; Muscles ; Obesity ; Rats ; Rats, Inbred OLETF ; Rats, Sprague-Dawley