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

Adipocytes ; cytology ; Humans ; Stem Cell Transplantation ; methods ; Stroke ; therapy

OBJECTIVETo investigate the possibility of directional differentiation of human adipose stem cells (hADSCs) into endothelial cells (EC), so as to provide seed cells for tissue engineered vessels.

METHODShADSCs were isolated from human adipose tissue by collagenase digestion, cultured and amplified by adherence to flasks. Then hADSCs were directionally induced to differentiate into EC by a combination of fibronectin (FN), endothelial cells support liquid (EGM2-MV) containing various growth factors and high concentration of VEGF165 (50 ng/ml). Then, the cells morphology, phenotype and function were identified.

RESULTSHighly homologous hADSCs were obtained, and then hADSCs were directionally differentiated into EC. CD31 and CD34, the specific markers for EC, and vascular endothelial growth factor receptor (KDR) were positive by immunohistochemical staining and RT-PCR. In addition, unique Weibel-Palade bodies in EC were observed under transmission electron microscope. Functionally, hADSCs could swallow Dil-Ac-LDL and form tube-like structures in matrigel after endothelial differentiation.

CONCLUSIONShADSCs can be successfully induced to differentiate into endothelial cells in vitro.

Adipocytes ; cytology ; Cell Differentiation ; Cells, Cultured ; Endothelial Cells ; cytology ; Humans ; Stem Cells ; cytology ; Tissue Engineering

OBJECTIVETo investigate the possibility of transdifferentiation of adipose mesenchymal stem cells (AMSCs) into hepatocytes.

METHODSHuman omentum adipose tissue was dispersed with collagenase I. Cells collected were cultured in a DMEM-F12 medium containing 2% FBS supplemented with 20 ng/ml HGF, 10 ng/ml FGF4, 1xITS and 0.1 micromol/L dexasmison. The cells of the control group were also cultured in the same kind of medium but without any cytokines serving as a control. The expression of hepatic transcriptional factors such as GATA4 and HNF1 were checked by RT-PCR. At the end of the induction, hepatocyte markers were analysed by flow cytometry, and cytokeratin expressions were examined using cyto-immunofluorescence methods.

RESULTSAMSCs grew like fibroblasts and were passaged easily. Most of the third passaged AMSCs were positive against anti-CD29, anti-CD44 antibodies, but negative for the anti-CD34 and anti-CD45 ones. The hepatic transcriptional factor was expressed gradually to higher levels during the induction time. AFP and Alb positive cells were 30.0% and 17.8% of the total cultured cells, and the rate of cells positive to the two markers was 6.9%. The inducted cells were positive for CK18 and CK19 antibodies at the end of the induction. The cells in the control group were negative when checked by these methods.

CONCLUSIONSAMSCs could be directed to differentiate into hepatocytes in vitro by a cytokine cocktail with a low concentration FBS culture system.

Adipocytes ; cytology ; Cell Differentiation ; Cell Transdifferentiation ; Cells, Cultured ; Hepatocytes ; cytology ; Humans ; Mesenchymal Stromal Cells ; cytology

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

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

Adipose-derived stem cells have self-renewal and multi-differentiation potentials, which can differentiate into smooth muscle cells, urinary epithelial-like cells, endothelial cells, neuron-like cells, etc. and secrete a variety of growth factors. As a result, the research on adipose-derived stem cells in lower urinary tract reconstruction using tissue engineering has been a highlight in recent years. This review focuses on the application of adipose-derived stem cells as seed cells to lower urinary tract reconstruction by tissue engineering in such diseases as bladder defect, stress urinary incontinence, and erectile dysfunction.
Adipocytes ; cytology ; Humans ; Stem Cells ; cytology ; Tissue Engineering ; Urinary Tract ; surgery

OBJECTIVE: How to increase the long-term retention rate of autologous fat grafting has been widely discussed. This study aimed to evaluate long-term fat graft retention rates for the most widely used fat processing methods in the area of facial esthetic surgery, including centrifugation, filtration, and sedimentation, using three-dimensional (3D) imaging. DATA SOURCES: PubMed, Embase, Wiley/Cochrane Library, and Web of Science databases were comprehensively searched from inception to July 2018 according to the guidelines of the American Society of Plastic Surgeons Fat Graft Task Force Assessment Methodology. STUDY SELECTION: Articles were screened using predetermined inclusion and exclusion criteria. Data collected included patient characteristics, follow-up devices, fat grafting techniques, and clinical outcomes. Patient cohorts were pooled, and fat graft retention rates were calculated. Complications were summarized according to different clinical characteristics. RESULTS: Of 77 articles, 10 clinical studies met the inclusion criteria and reported quantified measurement outcomes with 3D imaging which provide precise volumetric data with approximately 2% standard deviation compared to real volumes. Data of 515 patients were included. Fat grafting retention varied from 21% to 82%. We found filtration and centrifugation techniques could result in better retention outcomes. However, retention varied within each processing technique, with no significant difference among the 3 techniques. Twenty-two complications were reported among 515 patients, including donor-site hematoma (1 case), mild post-operative erythema (2 cases), mild volumetric asymmetries (2 cases), chronic edema (2 cases), overcorrection (2 cases), skin irregularity (6 cases), and headache or dysesthesia (7 cases). CONCLUSIONS Filtration and centrifugation techniques may result in better fat grafting retention outcomes than gravity sedimentation; however, more accurate statistical evidence is needed. Controversies continue to exist with respect to the performance of the different fat-processing techniques in fat graft retention.
Adipocytes ; cytology ; Adipose Tissue ; cytology ; Centrifugation ; methods ; Filtration ; methods ; Humans ; Imaging, Three-Dimensional ; methods

OBJECTIVE: To establish a primary culture method of human omental preadipocytes. METHODS: Using enzyme-digesting method, fibroblast-like cells from the human omental adipose tissues were cultured, and then differentiated by conditional medium, and identified by oil red O staining. RESULTS: The cultured cells were highly homogeneous, and highly proliferative in 4-5th generation. During the process of induction by conditional medium, the cells became round-like and larger, and more adipose droplets were aggregated. By oil red O staining, we confirmed the differentiated cells were mature adipocytes. CONCLUSION In human omental adipose tissues, there are some preadipocytes, which can differentiate into mature adipocytes with appropriate stimulus.
Adipocytes ; cytology ; Adult ; Cell Differentiation ; Cells, Cultured ; Culture Media, Conditioned ; Humans ; Male ; Omentum ; cytology

In recent years, there has been a growing emphasis on use of human adipose-derived stem cells (hADSCs) for cartilage tissue engineering owing to their ability to differentiate into chondrocytes, which is mainly induced by growth factors (GFs). In general, GFs for chondrogenic induction come from the transforming growth factor beta (TGF-beta) superfamily. To date, the most commonly used GFs for chondrogenes is TGF-beta1/3. However, the response of hADSCs to GFs may differ significantly from that of human bone marrow stem cells (hBMSCs). It has been reported that bone morphogenetic protein-6 (BMP-6) treatment induced TGF-beta receptor-I expression of hADSCs. It seems that these two cell populations varied strongly in their potency to undergo chondrogenesis in the same medium conditions. Here, we provide a concise review on various GFs used in chondrogenic differentiation of hADSCs in vitro.
Adipocytes ; cytology ; Cartilage ; Cell Differentiation ; Chondrocytes ; cytology ; Chondrogenesis ; Humans ; Stem Cells ; cytology ; TGF-beta Superfamily Proteins ; Tissue Engineering