Project description:We have identified a population of adipocytes in fat tissue that arise from bone marrow-derived progenitor cells. We used microarrays to compare the global gene expression patterns of the bone marrow progenitor-derived adipocytes as well as conventional white and brown adipocytes to evaluate the relationship between these adipocyte subpopulations. Gonadal fat tissue (for white adipocytes) and intrascapular fat tissue (for brown adipocytes) was digested with collagenase and adipocytes were recovered by centrifugation/flotation. Bone marrow derived adipocytes were isolated from the adipocyte fraction of gonadal fat tissue from mice receiving bone marrow tranplants from donors expressing either green fluorescent protein (GFP) or beta-galactosidase (LacZ) by flow cytometry.
Project description:We have identified a population of adipocytes in fat tissue that arise from bone marrow-derived progenitor cells. We used microarrays to compare the global gene expression patterns of the bone marrow progenitor-derived adipocytes as well as conventional white and brown adipocytes to evaluate the relationship between these adipocyte subpopulations.
Project description:The unique properties of the bone marrow allow for migration and proliferation of multipl myeloma (MM) cells, while also providing the perfect environment for development of quiescent, drug-resistant MM cell clones. Bone marrow adipocytes (BMAds), which have recently been identified as important contributors to systemic adipokine levels, bone strength, hematopoiesis, and progression of metastatic and primary bone marrow cancers, such as MM. Recent studies in myeloma suggest that BMAds can be reprogrammed by tumor cells to contribute to myeloma-induced bone disease, and reciprocally, BMAds support MM cells in vitro. Importantly, most data investigating BMAds have been generated using adipocytes derived by differentiating bone marrow-derived mesenchymal stromal cells (MSCs) into adipocytes in vitro using adipogenic media, due to the extreme technical challenges associated with isolating and culturing primary adipocytes. However, if studies could be performed with primary adipocytes, they likely will recapitulate in vivo biology better than MSC-derived adipocyte, as the differentiation process is artificial and differs from in vivo differentiation, and progenitor cell(s) of the primary BMAd may not be the same as the MSCs precursors used for adipogenic differentiation in vitro. Therefore, we developed and refined three methods for culturing primary BMAds (pBMAds): 2D coverslips, 2D transwells, and 3D silk scaffolds, all of which can be cultured alone or with MM cells to investigate bidirectional tumor-host signaling. To develop an in vitro model with a tissue-like structure to mimic the bone marrow microenvironment, we developed the first 3D, tissue engineered model utilizing pBMAds derived from human bone marrow. We found that pBMAds, which are extremely fragile, can be isolated and stably cultured in 2D for 10 days and in 3D for short term (~2 weeks) or long term (1 month) in vitro. To investigate the relationship between pBMAds and myeloma, MM cells can be added to investigate physical relationships through confocal imaging and soluble signaling molecules via mass spectrometry. In sum, we developed three in vitro cell culture systems to study primary bone marrow adipocytes and myeloma cells, which could be adapted to investigate many diseases and biological processes involving the bone marrow, including other bone-homing tumor types.
Project description:The aim of this study was to characterize the age-related gene expression profiles between bone marrow adipocytes and peripheral white adipocytes. Alterations of gene expression with aging were analyzed in bone marrow and peripheral white adipocytes isolated from C57BL/6J male mice using Affymetrix Mouse Gene 1.0 ST arrays. Bone marrow adipocytes and peripheral white adipocytes (n=6-10 animals per group) were isolated from male C57BL/6J mice (6-months, 14-months and 18-months of age). Samples were grouped into cell type (bone marrow adipocytes vs. peripheral adipocytes) and age (6-month (6M), 14-month (14M) and 18-month (18M)).
Project description:Ramirez2017 - Human global metabolism in
brown and white adipocytes
Recon 2.1A, an update to Recon 2.1x, is suitable for
quantitatively-realistic results for flux balance analysis in
human metabolism.
This model is described in the article:
Integrating Extracellular
Flux Measurements and Genome-Scale Modeling Reveals Differences
between Brown and White Adipocytes.
Ramirez AK, Lynes MD, Shamsi F, Xue
R, Tseng YH, Kahn CR, Kasif S, Dreyfuss JM.
Cell Rep 2017 Dec; 21(11):
3040-3048
Abstract:
White adipocytes are specialized for energy storage, whereas
brown adipocytes are specialized for energy expenditure.
Explicating this difference can help identify therapeutic
targets for obesity. A common tool to assess metabolic
differences between such cells is the Seahorse Extracellular
Flux (XF) Analyzer, which measures oxygen consumption and media
acidification in the presence of different substrates and
perturbagens. Here, we integrate the Analyzer's metabolic
profile from human white and brown adipocytes with a
genome-scale metabolic model to predict flux differences across
the metabolic map. Predictions matched experimental data for
the metabolite 4-aminobutyrate, the protein ABAT, and the
fluxes for glucose, glutamine, and palmitate. We also uncovered
a difference in how adipocytes dispose of nitrogenous waste,
with brown adipocytes secreting less ammonia and more urea than
white adipocytes. Thus, the method and software we developed
allow for broader metabolic phenotyping and provide a distinct
approach to uncovering metabolic differences.
This model is hosted on
BioModels Database
and identified by:
MODEL1703310000.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
Project description:The adipose organ, including white and brown adipose tissues, is an important player in systemic energy homeostasis, storing excess energy in form of lipids while releasing energy upon various energy demands. Recent studies have demonstrated that white and brown adipocytes also function as endocrine cells and regulate systemic metabolism by secreting factors that act locally and systemically. However, a comparative proteomic analysis of secreted factors from white and brown adipocytes and their responsiveness to adrenergic stimulation has not been reported yet. Therefore, we studied and compared the secretome of white and brown adipocytes, with and without norepinephrine (NE) stimulation. Our results reveal that in the absence of NE, carbohydrate metabolism-regulating proteins are preferably secreted from white adipocytes, while brown adipocytes predominantly secrete integrin signaling proteins. Upon NE stimulation, white adipocytes secrete more proteins involved in lipid metabolism, while brown adipocytes secrete more proteins with specific anti-inflammatory properties. In conclusion, our study provides a comprehensive catalogue of novel adipokine candidates secreted from white and brown adipocytes with many of them responsive to NE.
Project description:Secreted proteins from adipose tissue play a role in metabolic cross-talk and homeostasis. We performed high sensitivity mass spectrometry-based proteomics on the cell media of human adipocytes derived from the supraclavicular brown adipose and from the subcutaneous white adipose depots of adult humans. We identified 471 potentially secreted proteins covering interesting protein categories such as hormones, growth factors, extracellular matrix proteins and proteins of the complement system, which were differentially regulated in brown and white adipocytes. A total of 101 proteins were exclusively quantified in brown adipocytes and among these were ependymin-related protein 1 (EPDR1). Functional studies suggested a role for EPDR1 in thermogenic adipogenesis. In conclusion, we report substantial differences between the secretomes of brown and white human adipocytes and identify novel candidate batokines that can be important regulators of metabolism.
Project description:Expression profiling of progenitor cells from human supraclavicular and subcutaneous adipose tissue. Studies in animal models revealed that brown and white adipocytes derive from different progenitor cells. Molecular characteristics of these cells have not been investigated in detail in humans. Results provide evidence into the molecular basis of the difference of white and brown progenitor cells in humans.
Project description:The aim of this study was to characterize the age-related gene expression profiles between bone marrow adipocytes and peripheral white adipocytes. Alterations of gene expression with aging were analyzed in bone marrow and peripheral white adipocytes isolated from C57BL/6J male mice using Affymetrix Mouse Gene 1.0 ST arrays.
Project description:The aim of the project was to identify secreted proteins by human multipotent adipose derived stem cells differentiated into white and brown adipocytes.