Project description:The aim of this study was to characterize the obesity-related gene expression profiles between bone marrow adipocytes and peripheral white adipocytes from obese mice fed with high fat diet and leptin deficient mice Alterations of gene expression with high fat diet and in mice lacking leptin 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 this study was to characterize the obesity-related gene expression profiles between bone marrow adipocytes and peripheral white adipocytes from obese mice fed with high fat diet and leptin deficient mice Alterations of gene expression with high fat diet and in mice lacking leptin 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 ) fed with either standard chow or a high fat diet containg 60% calories from fat. Samples were grouped into diet (standard chow vs. high fat diet) and age (6-month (6M), 14-month (14M) and 18-month (18M)).
Project description:Adipogenin (Adig) is an adipocyte-enriched transmembrane protein. Its expression is induced during adipogenesis in rodent cells and a recent genome wide association study associated BMI-adjusted leptin levels with the ADIG locus. In order to begin to understand the biological function of adipogenin, we studied adipogenesis in Adig deficient cultured adipocytes and phenotyped Adig null (Adig-/-) mice. Data from Adig deficient cells showed that Adig is required for adipogenesis. In vivo, Adig-/- mice were leaner than wildtype mice when fed a high-fat diet and when crossed with Ob/Ob hyperphagic mice. In addition to the impact on adipogenesis and fat mass accrual, Adig deficiency also reduced fat mass adjusted plasma leptin levels and impaired leptin secretion from adipose explants, suggesting an additional direct impact on the regulation of leptin secretion.
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: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:The crosstalk between the bone and adipose tissue orchestrates the metabolic homeostasis, but the underlying mechanisms are largely unknown. Herein, we find that GCA+(grancalcin) immune cells accumulate in the bone marrow and release a sufficient amount of GCA into circulation during obesity. Genetic deletion of Gca in myeloid cells attenuates metabolic dysfunction in obese male mice, whereas injection of recombinant GCA into male mice cause adipose tissue inflammation and insulin resistance. Mechanistically, we found that GCA binds to the Prohibitin-2 (PHB2) receptor on adipocytes and activates the innate and adaptive immune response of adipocytes via the PAK1-NF-κB signaling pathway, thus provoking the infiltration of inflammatory immune cells. Moreover, GCA-neutralizing antibodies improve adipose tissue inflammation and insulin sensitivity in obese male mice. Together, these observations uncover a novel mechanism whereby bone marrow factor GCA initiates adipose tissue inflammation and insulin resistance, implicating GCA could be a potential target to treat metainflammation.
Project description:Obesity induces profound transcriptome changes in adipocytes; recent evidence suggests that lncRNAs play key roles in this process. Here, we performed a comprehensive transcriptome study by RNA-Seq in adipocytes isolated from interscapular brown, inguinal and epididymal white adipose tissues in diet-induced obese mice. Our analysis reveals a set of obesity-dysregulated lncRNAs, many of which exhibit dynamic changes in fed vs. fasted state, potentially serving as novel molecular markers reflecting adipose energy status. Among the most prominent ones is Lnc-leptin, an lncRNA transcribed from an enhancer region upstream of Leptin. Expression of Lnc-leptin is sensitive to insulin and closely correlates to Leptin expression across diverse pathophysiological conditions. Functionally, induction of Lnc-leptin is essential for adipogenesis, and its presence is required for a loop formation between exon2 of Lnc-leptin and promoter of Leptin in mature adipocytes and the maintenance of Leptin expression in vitro and in vivo. Our study establishes Lnc-leptin as a new regulator of Leptin.
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:Caloric restriction is considered to be anti-inflammatory. In this study we examined the effect of fasting on peripheral leukocyte populations. We found that short-term fasting affects metabolic and pro-inflammatory activity of monocytes and decreases numbers of circulating monocytes. For this study, we sorted hepatocytes from fed and fasted mice, monocytes from bone marrow from fed and fasted mice, and monocytes from bone marrow from wildtype and Ccr2-deficient mice.