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

Adipose Tissue ; cytology ; Heart ; physiology ; Humans ; Regeneration ; Stem Cells ; cytology

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

Adult pluripotent stem cells, such as mesenchymal stem cells derived from bone marrow and adipose tissue are capable of multilineage differentiation. Although autologous stem cell transplantation is an effective alternative to organ transplantation, the loss of cell viability and differentiation confinement of implanted cells has largely impaired the therapeutic efficacy. To produce biomaterial-free liver construct to integrate into living tissue, we isolated adipose mesenchymal stem cells and subjected them to a delicate culture configuration to mediate the hepatocyte differentiation. The differentiated hepatocyte-like cells were then inoculated onto poly (N-isopropylacrylamide) (PNIPAAm) grafted cell culture dish. By lowering the culture temperature to 20 degrees C, cells detached from the dish surface into a complete cell sheet. Hematoxylin and eosin staining and immunohistochemistry results showed that cell sheet was composed of 2-3 layers of cells and extracellular matrix was maintained intact. As compared with traditional cell harvest using trypsin digestion, cell sheet fabrication causes no damage to cell membrane and extracellular matrix. Hence, cell sheets would form a better interaction with tissues in situ, and a higher cell viability and therapeutic efficiency would be expected.
Adipose Tissue ; cytology ; Animals ; Cell Differentiation ; physiology ; Cells, Cultured ; Hepatocytes ; cytology ; Mesenchymal Stromal Cells ; cytology ; Rats ; Tissue Engineering ; methods

Rabbit bone marrow-derived mesenchymal stem cells(MSCs) are multipotent. We studied the adipogenic and osteogenic differentiation potent using adipogenic supplement (AS) or osteogenic supplement (OS) in vitro. Specific markers of this induced adipogenic and osteogenic lineage were identified. The findings showed that the rabbit MSCs are capable of differentiating into adipogenic and osteogenic lineages spontaneously. On the 21st day, approximately 75% rabbit MSCs were induced to adipogenic or osteogenic cells in medium containing AS or OS, respectively. These results demonstrated that the differentiation of MSCs could be regulated in vitro. The underlying molecular mechanisms of adipogenic or osteogenic differentiation await elucidation.
Adipose Tissue ; cytology ; Animals ; Bone and Bones ; cytology ; Cell Differentiation ; Cell Lineage ; In Vitro Techniques ; Mesoderm ; cytology ; Rabbits ; Stem Cells ; cytology

Mesenchymal stem cells (MSCs) could be obtained from many sources, and there are differences between them. This study was purposed to compare and analyze the basic biological characteristics of umbilical cord, adipose tissue-and bone marrow-derived MSC (UC-MSCs, AD-MSCs and BM-MSCs). The MSCs were isolated from umbilical cord, adipose tissue and bone marrow were cultured; the morphology of UC-MSCs, AD-MSCs and BM-MSCs was observed by using microscopy; the immunophenotype, differentiation potential and expression of peroxisome proliferation-activated receptor-γ (PPAR-γ) mRNA were detected by using flow cytometry, differentiation test (von kossais and 0:1 red O staining) and quantitative fluorescent PCR, respectively. The results showed that the UC-MSCs, AD-MSCs and BM-MSCs displayed similar morphology under confocal microscope after being stained with rhodamine phalloidin and DAPL. The immunophenotypes of these three originated cells conform to coincide with identification criterion for MSCs, and showed similar expression level. During adipogenic induction the adipogenic potential of these MSCs was different, AD-MSCs exhibited the highest adipogenic potential, UC-MSCs displayed the lowest, while potential of BM-MSCs get between; however, the osteogenic differentiation potential of UC-MSCs, AD-MSCs and BM-MSCs was similar. The PCR detection showed that the expression level of PPAR-γ mRNA was the highest in AD-MSCs and the lowest in UC-MSCs, while expression level in BM-MSCs get between, these results were identical with the adipogenic potential, suggest that the difference of adipogenic potential in 3 kinds of MSCs was associated with basic expression level of PPAR-γ mRNA. It is concluded that UC-MSCs, AD-MSCs and BM-MSCs exhibit similar morphology, the immunophenotypes of these MSCs coincide with identification criterion for MSCs, the osteogenic potential of these MSCs is similar, while the adipogenic potential and the expression level of PPAR-γ mRNA are different. The difference-associated mechanisms need to further study.
Adipogenesis ; Adipose Tissue ; cytology ; Bone Marrow Cells ; cytology ; Cell Separation ; Cells, Cultured ; Humans ; Mesenchymal Stromal Cells ; cytology ; Umbilical Cord ; cytology

OBJECTIVETo explore the feasibility of the transdiferentiation of human breast adipose-derived stem cells (hbASCs) into mammary epithelial-like cells after co-culturing in Transwell in vitro.

METHODSThe third passage hbASC and the HBL-100 cell line were co-cultured in a Transwell culture system for 15 days. The hbASCs were observed and identified by inverted phase contrast microscope and transmission electron microscopy, and immunocytochemistry staining in the induced and control groups.

RESULTSBoth the third passage hbASCs and the HBL-100 cell line cells could adhere and grow rapidly after co-culture in the Transwell system. After co-culture for 15 days, the morphology of some induced hbASCs changed into epithelial-like cells. Some induced hbASCs showed positive expression of CK18, CK19 by immunocytochemistry staining, and typical epithelium cells with microvilli, desmosomes and tonofilaments observed under TEM. The positive rate of CK18 and CK19 was (24.4 +/- 12.0)% and (21.6 +/- 16.4)% in experimental group, and (1.8 +/- 1.7)% and (1.1 +/- 0.6)% in control group.

CONCLUSIONThe data suggests that hbASCs may have the potential to transdifferentiate into human mammary epithelial-like cells after co-culturing in Transwell in vitro.

Adipose Tissue ; cytology ; Breast ; cytology ; Cell Differentiation ; Cells, Cultured ; Coculture Techniques ; Epithelial Cells ; cytology ; Female ; Humans ; Stem Cells ; cytology

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

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

OBJECTIVETo investigate the effect of adipose stromal vascular fraction cells (SVFs) on the survival rate of fat transplantation.

METHODS0. 5 ml autologous fat tissue was mixed with: 1) Di-labeled autologous SVFs ( Group A); 2) Di-labeled autologous adipose-derived stem cells (ASCs) (Group B); 3)Complete DMEM (Group C). And then the mixture was injected randomly under the back skin of 14 rabbits. The transplanted fat tissue in three groups was harvested at 6 months after implantation. Wet weight of fat grafts was measured for macroscopic aspects. After HE staining, blood vessel density, viable adipocytes and fibrous proliferation were counted respectively for histological evaluation. Trace of DiI-labeled ASCs in vivo was detected by fluorescent microscope.

RESULTSThe wet weight of fat grafts in group A (291.0 +/- 72.1) mg and group B (269.3 +/- 67.3) mg was significantly higher than that in group C (177.8 +/- 60.0) mg, but the difference between Group A and Group B was not significant. Histological analysis revealed that the fat grafts in group A and B was consisted predominantly of adipose tissue with less fat necrosis and fibrosis, compared with the fat grafts in group C. The grafts in both group A and B had significantly higher capillary density than those in the control group. Part of vascular endothelial cells were observed to origin from ectogenic DiI-labeled SVFs and ASCs.

CONCLUSIONSThe autologous isolated SVFs has a similar effect as autologous cultured ASCs to improve the survival rate of fat transplantation. And the former is more practical and safe, indicating a wide clinical application in the future.

Adipose Tissue ; cytology ; transplantation ; Animals ; Cells, Cultured ; Graft Survival ; Rabbits ; Stromal Cells ; cytology