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1.
Biomolecules ; 11(7)2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34356649

RESUMO

Curcumin is a known anti-adipogenic agent for alleviating obesity and related disorders. Comprehensive comparisons of the anti-adipogenic activity of curcumin with other curcuminoids is minimal. This study compared adipogenesis inhibition with curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC), and their underlying mechanisms. We differentiated 3T3-L1 cells in the presence of curcuminoids, to determine lipid accumulation and triglyceride (TG) production. The expression of adipogenic transcription factors and lipogenic proteins was analyzed by Western blot. A significant reduction in Oil red O (ORO) staining was observed in the cells treated with curcuminoids at 20 µM. Inhibition was increased in the order of curcumin < DMC < BDMC. A similar trend was observed in the detection of intracellular TG. Curcuminoids suppressed differentiation by downregulating the expression of peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), leading to the downregulation of the lipogenic enzymes acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS). AMP-activated protein kinase α (AMPKα) phosphorylation was also activated by BDMC. Curcuminoids reduced the release of proinflammatory cytokines and leptin in 3T3-L1 cells in a dose-dependent manner, with BDMC showing the greatest potency. BDMC at 20 µM significantly decreased leptin by 72% compared with differentiated controls. Molecular docking computation indicated that curcuminoids, despite having structural similarity, had different interaction positions to PPARγ, C/EBPα, and ACC. The docking profiles suggested a possible interaction of curcuminoids with C/EBPα and ACC, to directly inhibit their expression.


Assuntos
Adipogenia/efeitos dos fármacos , Diarileptanoides/química , Diarileptanoides/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/fisiologia , Adipocinas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Curcuma/química , Curcumina/análise , Curcumina/farmacologia , Enzimas/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Simulação de Acoplamento Molecular , PPAR gama/química , PPAR gama/metabolismo , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Triglicerídeos/metabolismo
2.
Biomolecules ; 11(7)2021 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-34356676

RESUMO

Genistein (4,5,7-trihydroxyisoflavone) is abundant in various dietary vegetables, especially soybeans, and is known to have not only an estrogenic effect but also an antiadipogenic effect. Atorvastatin (dihydroxy monocarboxylic acid) is a statin used to prevent heart disease. Although genistein and atorvastatin have been reported to possess antiadipogenic effects, their combined effects are still unclear. The aim of the current study was to explore whether the combination of genistein and atorvastatin at low concentrations significantly suppresses adipogenesis in a murine preadipocyte cell line (3T3-L1) compared to treatment with genistein or atorvastatin alone. Our results showed that cotreatment with 50 µM genistein and 50 nM atorvastatin significantly suppressed preadipocyte differentiation, whereas when each compound was used alone, there was no inhibitory effect. Additionally, cotreatment with genistein and atorvastatin significantly downregulated adipogenic marker proteins, including mitogen-activated protein kinases (MAPKs), peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein alpha (C/EBPα), glucocorticoid receptor (GR), and CCAAT/enhancer-binding protein ß (C/EBPß). This is the first evidence of the combined antiadipogenic effects of genistein and atorvastatin. Although additional experiments are required, combinational treatment with genistein and atorvastatin may be an alternative treatment for menopause-associated lipid metabolic disorders and obesity.


Assuntos
Adipogenia/efeitos dos fármacos , Atorvastatina/farmacologia , Genisteína/farmacologia , Células 3T3-L1 , Adipogenia/fisiologia , Animais , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Diferenciação Celular/efeitos dos fármacos , Sinergismo Farmacológico , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , PPAR gama/metabolismo , Receptores de Glucocorticoides/metabolismo
3.
FASEB J ; 35(9): e21868, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34449920

RESUMO

Brown adipose tissue (BAT) plays an important role on no shivering thermogenesis during cold exposure to maintain animal body temperature and energy homeostasis. However, knowledge of the cellular transition from white adipose tissue (WAT) to BAT is still limited. In this study, we provided a comprehensive metabolomics and transcriptional signatures of goat BAT and WAT. A total of 157 metabolites were significantly changed, including 81 upregulated and 76 downregulated metabolites. In addition, we identified the citric acid cycle, fatty acid elongation, and degradation pathways as coordinately activated in BAT. Interestingly, five unsaturated fatty acids (Eicosadienoic Acid, C20:2; γ-Linolenic acid, C20:3; Arachidonic Acid, C20:4; Adrenic acid, C22:4; Docosahexaenoic acid, C22:6), Succinate, L-carnitine, and L-palmitoyl-carnitine were found to be abundant in BAT. Furthermore, L-carnitine, an intermediate of fatty acid degradation, is required for goat brown adipocyte differentiation and thermogenesis through activating AMPK pathway. However, L-carnitine decreased lipid accumulation through inducing lipolysis and thermogenesis in white adipocytes. These results revealed that there are the significant alterations in transcriptomic and metabolomic profiles between goat WAT and BAT, which may contribute to better understanding the roles of metabolites in BAT thermogenesis process.


Assuntos
Tecido Adiposo Marrom/metabolismo , Cabras/metabolismo , Termogênese/fisiologia , Adipogenia/fisiologia , Tecido Adiposo Branco/metabolismo , Animais , Diferenciação Celular/fisiologia , Regulação para Baixo/fisiologia , Metabolismo Energético/fisiologia , Ácidos Graxos Insaturados/metabolismo , Homeostase/fisiologia , Lipólise/fisiologia , Metabolômica/métodos , RNA-Seq/métodos , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia
4.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203452

RESUMO

Adipokines secreted by hypertrophic visceral adipose tissue (VAT) instigate low-grade inflammation, followed by hyperglycemia (HG)-related metabolic disorders. The latter may develop with the participation of epigenetic modifications. Our aim was to assess how HG influences selected epigenetic modifications and the expression of interleukin 6 (IL-6) and adiponectin (APN; gene symbol ADIPOQ) during the adipogenesis of human visceral preadipocytes (HPA-v). Adipocytes (Ads) were chronically or transiently HG-treated during three stages of adipogenesis (proliferation, differentiation, maturation). We measured adipokine mRNA, protein, proven or predicted microRNA expression (RT-qPCR and ELISA), and enrichment of H3K9/14ac, H3K4me3, and H3K9me3 at gene promoter regions (chromatin immunoprecipitation). In chronic HG, we detected different expression patterns of the studied adipokines at the mRNA and protein levels. Chronic and transient HG-induced changes in miRNA (miR-26a-5p, miR-26b-5p, let-7d-5p, let-7e-5p, miR-365a-3p, miR-146a-5p) were mostly convergent to altered IL-6 transcription. Alterations in histone marks at the IL6 promoter were also in agreement with IL-6 mRNA. The open chromatin marks at the ADIPOQ promoter mostly reflected the APN transcription during NG adipogenesis, while, in the differentiation stage, HG-induced changes in all studied marks were in line with APN mRNA levels. In summary, HG dysregulated adipokine expression, promoting inflammation. Epigenetic changes coexisted with altered expression of adipokines, especially for IL-6; therefore, epigenetic marks induced by transient HG may act as epi-memory in Ads. Such changes in the epigenome and expression of adipokines could be instrumental in the development of inflammation and metabolic deregulation of VAT.


Assuntos
Adipócitos/metabolismo , Adiponectina/metabolismo , Hiperglicemia/metabolismo , Regiões Promotoras Genéticas/genética , Adipogenia/genética , Adipogenia/fisiologia , Adiponectina/genética , Imunoprecipitação da Cromatina , Ensaio de Imunoadsorção Enzimática , Epigênese Genética/genética , Epigênese Genética/fisiologia , Humanos , Hiperglicemia/genética , Interleucina-6/metabolismo
5.
Int J Mol Sci ; 22(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34281266

RESUMO

Bone marrow stromal cells (BMSCs) are multipotent cells which can differentiate into chondrocytes, osteoblasts, and fat cells. Under pathological stress, reduced bone formation in favour of fat formation in the bone marrow has been observed through a switch in the differentiation of BMSCs. The bone/fat switch causes bone growth defects and disordered bone metabolism in bone marrow, for which the mechanisms remain unclear, and treatments are lacking. Studies suggest that small non-coding RNAs (microRNAs) could participate in regulating BMSC differentiation by disrupting the post-transcription of target genes, leading to bone/fat formation changes. This review presents an emerging concept of microRNA regulation in the bone/fat formation switch in bone marrow, the evidence for which is assembled mainly from in vivo and in vitro human or animal models. Characterization of changes to microRNAs reveals novel networks that mediate signalling and factors in regulating bone/fat switch and homeostasis. Recent advances in our understanding of microRNAs in their control in BMSC differentiation have provided valuable insights into underlying mechanisms and may have significant potential in development of new therapeutics.


Assuntos
Adipogenia/genética , Adipogenia/fisiologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , Animais , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Sinalização do Cálcio/genética , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Marcadores Genéticos , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Modelos Biológicos , Transdução de Sinais/genética , Proteínas Smad/genética , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Via de Sinalização Wnt/genética
6.
Am J Physiol Cell Physiol ; 321(2): C257-C268, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34106790

RESUMO

Animal models clearly illustrate that the maintenance of skeletal muscle mass depends on the function and interaction of a heterogeneous population of resident and infiltrating mononuclear cells. Several lines of evidence suggest that mononuclear cells also play a role in muscle wasting in humans, and targeting these cells may open new treatment options for intervention or prevention in sarcopenia. Methodological and ethical constraints have perturbed exploration of the cellular characteristics and function of mononuclear cells in human skeletal muscle. Thus, investigations of cellular phenotypes often depend on immunohistochemical analysis of small tissue samples obtained by needle biopsies, which do not match the deep phenotyping of mononuclear cells obtained from animal models. Here, we have developed a protocol for fluorescence-activated cell sorting (FACS), based on single-cell RNA-sequencing data, for quantifying and characterizing mononuclear cell populations in human skeletal muscle. Muscle stem cells, fibro-adipogenic progenitors, and two subsets of macrophages (CD11c+/-) are present in needle biopsies in comparable quantities per milligram tissue to open surgical biopsies. We find that direct cell isolation is preferable due to a substantial shift in transcriptome when using preculture before the FACS procedure. Finally, in vitro validation of the cellular phenotype of muscle stem cells, fibro-adipogenic progenitors, and macrophages confirms population-specific traits. This study demonstrates that mononuclear cell populations can be quantified and subsequently analyzed from needle biopsy material and opens the perspective for future clinical studies of cellular mechanisms in muscle wasting.


Assuntos
Biópsia , Diferenciação Celular/fisiologia , Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/citologia , Adipogenia/fisiologia , Biópsia/métodos , Separação Celular/métodos , Citometria de Fluxo/métodos , Humanos , Macrófagos/citologia
7.
Diabetes ; 70(7): 1419-1430, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34155042

RESUMO

Wnt signaling is an ancient and evolutionarily conserved pathway with fundamental roles in the development of adipose tissues. Roles of this pathway in mesenchymal stem cell fate determination and differentiation have been extensively studied. Indeed, canonical Wnt signaling is a significant endogenous inhibitor of adipogenesis and promoter of other cell fates, including osteogenesis, chondrogenesis, and myogenesis. However, emerging genetic evidence in both humans and mice suggests central roles for Wnt signaling in body fat distribution, obesity, and metabolic dysfunction. Herein, we highlight recent studies that have begun to unravel the contributions of various Wnt pathway members to critical adipocyte functions, including carbohydrate and lipid metabolism. We further explore compelling evidence of complex and coordinated interactions between adipocytes and other cell types within adipose tissues, including stromal, immune, and endothelial cells. Given the evolutionary conservation and ubiquitous cellular distribution of this pathway, uncovering the contributions of Wnt signaling to cell metabolism has exciting implications for therapeutic intervention in widespread pathologic states, including obesity, diabetes, and cancers.


Assuntos
Adipócitos/fisiologia , Lipogênese/fisiologia , Células-Tronco Mesenquimais/fisiologia , Via de Sinalização Wnt/fisiologia , Adipogenia/fisiologia , Animais , Humanos , Doenças Metabólicas/etiologia , Camundongos , Osteoblastos/fisiologia , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , beta Catenina/fisiologia
8.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069744

RESUMO

Bisphenol A (BPA) is an endocrine-disrupting chemical used in the production of plastics, and is linked to developmental, reproductive, and metabolic disorders including obesity. Manufacturers have begun using 'BPA-free' alternatives instead of BPA in many consumer products. However, these alternatives have had much less testing and oversight, yet they are already being mass-produced and used across industries from plastics to food-contact coatings. Here, we used human female adipose-derived stem cells (hASCs), a type of adult mesenchymal stem cell, to compare the effects of BPA and BPA alternatives on adipogenesis or fat cell development in vitro. We focused on two commonly used BPA replacements, bisphenol AF (BPAF) and tetramethyl bisphenol F (TMBPF; monomer of the new valPure V70 food-contact coating). Human ASCs were differentiated into adipocytes using chemically defined media in the presence of control differentiation media with and without 17ß-estradiol (E2; 10 µM), or with increasing doses of BPA (0, 0.1 and 1 µM), BPAF (0, 0.1, 1 and 10 nM), or TMBPF (0, 0.01 and 0.1 µM). After differentiation, the cells were stained and imaged to visualize and quantify the accumulation of lipid vacuoles and number of developing fat cells. Treated cells were also examined for cell viability and apoptosis (programmed cell death) using the respective cellular assays. Similar to E2, BPA at 0.1 µM and BPAF at 0.1 nM, significantly increased adipogenesis and lipid production by 20% compared to control differentiated cells (based on total lipid vacuole number to cell number ratios), whereas higher levels of BPA and BPAF significantly decreased adipogenesis (p < 0.005). All tested doses of TMBPF significantly reduced adipogenesis and lipid production by 30-40%, likely at least partially through toxic effects on stem cells, as viable cell numbers decreased and apoptosis levels increased throughout differentiation. These findings indicate that low, environmentally-relevant doses of BPA, BPAF, and TMBPF have significant effects on fat cell development and lipid accumulation, with TMBPF having non-estrogenic, anti-adipogenic effects. These and other recent results may provide a potential cellular mechanism between exposure to bisphenols and human obesity, and underscore the likely impact of these chemicals on fat development in vivo.


Assuntos
Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Adipócitos/efeitos dos fármacos , Adipogenia/fisiologia , Tecido Adiposo/efeitos dos fármacos , Células-Tronco Adultas/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Compostos Benzidrílicos/efeitos adversos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Estradiol/farmacologia , Feminino , Humanos , Obesidade/metabolismo , Fenóis/efeitos adversos , Células-Tronco/efeitos dos fármacos
9.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065474

RESUMO

Obesity-induced adipose tissue dysfunction and disorders of glycolipid metabolism have become a worldwide research priority. Zfp217 plays a crucial role in adipogenesis of 3T3-L1 preadipocytes, but about its functions in animal models are not yet clear. To explore the role of Zfp217 in high-fat diet (HFD)-induced obese mice, global Zfp217 heterozygous knockout (Zfp217+/-) mice were constructed. Zfp217+/- mice and Zfp217+/+ mice fed a normal chow diet (NC) did not differ significantly in weight gain, percent body fat mass, glucose tolerance, or insulin sensitivity. When challenged with HFD, Zfp217+/- mice had less weight gain than Zfp217+/+ mice. Histological observations revealed that Zfp217+/- mice fed a high-fat diet had much smaller white adipocytes in inguinal white adipose tissue (iWAT). Zfp217+/- mice had improved metabolic profiles, including improved glucose tolerance, enhanced insulin sensitivity, and increased energy expenditure compared to the Zfp217+/+ mice under HFD. We found that adipogenesis-related genes were increased and metabolic thermogenesis-related genes were decreased in the iWAT of HFD-fed Zfp217+/+ mice compared to Zfp217+/- mice. In addition, adipogenesis was markedly reduced in mouse embryonic fibroblasts (MEFs) from Zfp217-deleted mice. Together, these data indicate that Zfp217 is a regulator of energy metabolism and it is likely to provide novel insight into treatment for obesity.


Assuntos
Metabolismo Energético/fisiologia , Obesidade/metabolismo , Obesidade/fisiopatologia , Transativadores/metabolismo , Adipócitos Brancos/metabolismo , Adipócitos Brancos/fisiologia , Adipogenia/fisiologia , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/fisiopatologia , Animais , Dieta Hiperlipídica , Fibroblastos/metabolismo , Fibroblastos/fisiologia , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Termogênese/fisiologia , Ganho de Peso/fisiologia
10.
Biochem Biophys Res Commun ; 557: 97-103, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33862466

RESUMO

Understanding of the mechanism of adipogenesis is essential for the control of obesity, which predisposes toward numerous health problems. High-mobility group box protein 2 (HMGB2) is a non-histone chromosomal protein that facilitates DNA replication, transcription, recombination, and repair. Here, we studied the role of HMGB2 in adipogenic differentiation. The expression of HMGB2 was measured at the mRNA and protein levels in cultured 3T3-L1 pre-adipocyte cells and during the process of adipogenic differentiation induced bya cocktail of insulin, 3-isobutyl-1-methylxanthine, and dexamethasone. This increased in the early phase and decreased in the late phase of differentiation. However, 3T3-L1 pre-adipocyte cells did not differentiate into adipocytes after the knockdown of HMGB2 expression by small interfering RNA (siRNA). Similarly, mesenchymal stem cells (MSCs) isolated from Hmgb2-/- mice did not express peroxisome proliferator-activated receptor gamma (PPARγ) in response to the adipocyte differentiation cocktail and did not differentiate. Wnt/ß-catenin signaling is a negative regulator of adipogenic differentiation. We found that ß-catenin expression was downregulated during 3T3-L1 adipogenic differentiation, as expected, but not when endogenous HMBG2 expression was knocked down using siRNA. These results indicate that HMGB2 plays an essential role in the early phase of the differentiation of pre-adipocytes and MSCs, and probably interacts with other regulators, such as PPARγ and Wnt/ß-catenin signaling.


Assuntos
Adipócitos/citologia , Adipogenia/fisiologia , Proteína HMGB2/metabolismo , Células-Tronco Mesenquimais/citologia , Via de Sinalização Wnt , Adipócitos/metabolismo , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
11.
Nat Metab ; 3(4): 469-484, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33846639

RESUMO

Brown adipose tissue can expend large amounts of energy, and therefore increasing its size or activity is a promising therapeutic approach to combat metabolic disease. In humans, major deposits of brown fat cells are found intimately associated with large blood vessels, corresponding to perivascular adipose tissue (PVAT). However, the cellular origins of PVAT are poorly understood. Here, we determine the identity of perivascular adipocyte progenitors in mice and humans. In mice, thoracic PVAT develops from a fibroblastic lineage, consisting of progenitor cells (Pdgfra+, Ly6a+ and Pparg-) and preadipocytes (Pdgfra+, Ly6a+ and Pparg+), which share transcriptional similarity with analogous cell types in white adipose tissue. Interestingly, the aortic adventitia of adult animals contains a population of adipogenic smooth muscle cells (Myh11+, Pdgfra- and Pparg+) that contribute to perivascular adipocyte formation. Similarly, human PVAT contains presumptive fibroblastic and smooth muscle-like adipocyte progenitor cells, as revealed by single-nucleus RNA sequencing. Together, these studies define distinct populations of progenitor cells for thermogenic PVAT, providing a foundation for developing strategies to augment brown fat activity.


Assuntos
Adipócitos Marrons/fisiologia , Tecido Adiposo Marrom/fisiologia , Linhagem da Célula/fisiologia , Termogênese/fisiologia , Adipócitos Brancos/fisiologia , Adipogenia/fisiologia , Tecido Adiposo Marrom/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos , Aorta/citologia , Aorta/fisiologia , Vasos Sanguíneos/fisiologia , Linhagem da Célula/genética , Fibroblastos/fisiologia , Regulação da Expressão Gênica/fisiologia , Humanos , Recém-Nascido , Camundongos , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/fisiologia , Células-Tronco/fisiologia , Termogênese/genética
12.
Mol Cell Biochem ; 476(7): 2837-2845, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33730298

RESUMO

Lipid metabolism, which encompasses synthesis and degradation of lipids, is critical for a wide range of cellular functions, including structural and morphological properties of organelles, energy storage, signalling, and the stability and function of membrane proteins. Adipose tissue is a dynamic tissue type that performs a lot of significant physiological functions, including secretion, and is involved in maintaining homeostasis and in regulatory roles of other tissues based on paracrine or endocrine. More recently, several classes of non-coding RNAs (ncRNAs), such as long non-coding RNA (lncRNA), microRNA (miRNA) and circular RNA (circRNA), have been discovered in adipocytes, and they act as critical regulators of gene expression in adipogenesis and regulate adipogenesis through multiple pathways. In the present paper, we discussed several classes of non-coding RNAs and summarized the latest research on the regulatory role of ncRNAs in bovine adipogenesis. We gave examples for known modes of action to look forward to providing reference information future scientific research in cattle breeding.


Assuntos
Adipogenia/fisiologia , Tecido Adiposo Branco/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Bovinos
13.
J Biol Chem ; 296: 100488, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33662399

RESUMO

Differentiation of mesenchymal stem cells into adipocyte requires coordination of external stimuli and depends upon the functionality of the primary cilium. The Rab8 small GTPases are regulators of intracellular transport of membrane-bound structural and signaling cargo. However, the physiological contribution of the intrinsic trafficking network controlled by Rab8 to mesenchymal tissue differentiation has not been fully defined in vivo and in primary tissue cultures. Here, we show that mouse embryonic fibroblasts (MEFs) lacking Rab8 have severely impaired adipocyte differentiation in vivo and ex vivo. Immunofluorescent localization and biochemical analyses of Rab8a-deficient, Rab8b-deficient, and Rab8a and Rab8b double-deficient MEFs revealed that Rab8 controls the Lrp6 vesicular compartment, clearance of basal signalosome, traffic of frizzled two receptor, and thereby a proper attenuation of Wnt signaling in differentiating MEFs. Upon induction of adipogenesis program, Rab8a- and Rab8b-deficient MEFs exhibited severely defective lipid-droplet formation and abnormal cilia morphology, despite overall intact cilia growth and ciliary cargo transport. Our results suggest that intracellular Rab8 traffic regulates induction of adipogenesis via proper positioning of Wnt receptors for signaling control in mesenchymal cells.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt , Proteínas rab de Ligação ao GTP/metabolismo , Adipogenia/fisiologia , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Cílios/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Camundongos , Camundongos Knockout , Proteínas rab de Ligação ao GTP/genética
14.
Am J Physiol Cell Physiol ; 320(6): C1000-C1012, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33788629

RESUMO

Obesity, especially visceral fat accumulation, increases the risk of type 2 diabetes (T2D). The purpose of this study was to investigate the impact of T2D on the pancreatic fat depot. Pancreatic fat pads from 17 partial pancreatectomized patients (PPP) were collected, pancreatic preadipocytes isolated, and in vitro differentiated. Patients were grouped using HbA1c into normal glucose tolerant (NGT), prediabetic (PD), and T2D. Transcriptome profiles of preadipocytes and adipocytes were assessed by RNAseq. Insulin sensitivity was estimated by quantifying AKT phosphorylation on Western blots. Lipogenic capacity was assessed with oil red O staining, lipolytic activity via fatty acid release. Secreted factors were measured using ELISA. Comparative transcriptome analysis of preadipocytes and adipocytes indicates defective upregulation of genes governing adipogenesis (NR1H3), lipogenesis (FASN, SCD, ELOVL6, and FADS1), and lipolysis (LIPE) during differentiation of cells from T2D-PPP. In addition, the ratio of leptin/adiponectin mRNA was higher in T2D than in NGT-PPP. Preadipocytes and adipocytes of NGT-PPP were more insulin sensitive than T2D-PPP cells in regard to AKT phosphorylation. Triglyceride accumulation was similar in NGT and T2D adipocytes. Despite a high expression of the receptors NPR1 and NPR2 in NGT and T2D adipocytes, lipolysis was stimulated by ANP 1.74-fold in NGT cells only. This stimulation was further increased by the PDE5 inhibitor dipyridamole (3.09-fold). Dipyridamole and forskolin increased lipolysis receptor independently 1.88-fold and 1.48-fold, respectively, solely in NGT cells. In conclusion, the metabolic status persistently affects differentiation and lipolysis of pancreatic adipocytes. These alterations could aggravate the development of T2D.


Assuntos
Adipócitos/fisiologia , Adipogenia/fisiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Lipogênese/fisiologia , Lipólise/fisiologia , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular/fisiologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/fisiopatologia , Pâncreas/metabolismo , Pâncreas/fisiopatologia , Fosforilação/fisiologia , Triglicerídeos/metabolismo
15.
Biomed Pharmacother ; 138: 111438, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33721756

RESUMO

Roselle (Hibiscus sabdariffa) is reported to be beneficial in treating obesity which can develop into a range of metabolic disorders. The molecular mechanisms by which roselle extract works to prevent obesity-related insulin resistance remains poorly understood. We hypothesized that the roselle extract can decrease lipid accumulation and improve insulin resistance by downregulating adipogenesis. The aim of this study is to investigate the protective effect of roselle extract on the mechanism of adipogenesis and prevent complications of the obesity-related insulin resistance in high-fat diet-induced obese rats for 8 weeks. Male Sprague Dawley rats were divided into 4 groups: control (C), high-fat diet (HFD), high-fat diet supplemented with 250 mg/kg BW of roselle (R250), and high-fat diet supplemented with 500 mg/kg BW of roselle (R500). The results demonstrated that roselle had the potential to reduce body weight, food intake, lipid profiles, inflammatory cytokines, lipid peroxidation, serum leptin, insulin and duodenal glucose absorption, while significantly increased glucose uptake of adipose tissue and muscle when compared to the HFD group. Roselle can prevent lipid accumulation by suppressing differentiation of 3T3-L1 adipocyte by downregulating the adipogenic gene expression. The results of this study demonstrated that the molecular mechanism underlying the protective effect of roselle, could be an alternative approach for obesity-related insulin resistance prevention.


Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Hibiscus , Obesidade/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Células 3T3-L1 , Adipócitos/metabolismo , Adipogenia/fisiologia , Animais , Fármacos Antiobesidade/isolamento & purificação , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Relação Dose-Resposta a Droga , Flores , Resistência à Insulina/fisiologia , Masculino , Camundongos , Obesidade/etiologia , Obesidade/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley
16.
J Endocrinol ; 249(2): 83-93, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33705351

RESUMO

Obesity is an increasingly serious epidemic worldwide characterized by an increase in the number and size of adipocytes. Adipose tissue maintains the balance between lipid storage and energy utilization. Therefore, adipose metabolism is of great significance for the prevention, treatment and intervention of obesity. Asprosin, a novel adipokine, is a circulating hormone mainly secreted by white adipose tissue. Previous studies have shown that asprosin plays a role in fasting-induced homeostasis, insulin resistance, and glucose tolerance. However, whether it can regulate the metabolism of adipose tissue itself has not been studied. This study intended to examine the roles and potential mechanisms of asprosin in adipose regulation. We first demonstrated that the expression level of asprosin was significantly downregulated in subcutaneous white adipose tissue (scWAT) of high-fat diet (HFD)-fed or cold-stimulated mice. Overexpression of asprosin in scWAT reduced heat production, decreased expression of the browning marker uncoupling protein 1 (UCP1) and other browning-related genes, along with upregulation of adipogenic gene expression. Mechanistically, we found that Nrf2 was activated upon cold exposure, but this activation was suppressed after asprosin overexpression. In primary cultured adipocytes, adenovirusmediated asprosin overexpression inhibited adipose browning and aggravated lipid deposition, while Nrf2 agonist oltipraz could reverse these changes. Our findings suggest that novel adipokine asprosin negatively regulated browning and elevate lipid deposition in adipose tissue via a Nrf2-mediated mechanism. Asprosin may be a promising target for the prevention and treatment of obesity and other metabolic diseases.


Assuntos
Adipogenia/fisiologia , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Fibrilina-1/metabolismo , Fragmentos de Peptídeos/metabolismo , Hormônios Peptídicos/metabolismo , Animais , Diferenciação Celular , Temperatura Baixa , Dieta Hiperlipídica/efeitos adversos , Regulação para Baixo , Metabolismo Energético , Fibrilina-1/genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fragmentos de Peptídeos/genética , Hormônios Peptídicos/genética , Distribuição Aleatória , Regulação para Cima
17.
J Steroid Biochem Mol Biol ; 210: 105850, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33639236

RESUMO

11ß-Hydroxysteroid dehydrogenase 1 (11ß-HSD1) plays an important role in pre-receptor glucocorticoid metabolism. This enzyme is expressed in bone, increases with age, and catalyzes the conversion of the inactive glucocorticoid cortisone into the active glucocorticoid cortisol and vice versa. Here we hypothesized that the physiological activity of 11ß-HSD1 to produce cortisol in human mesenchymal progenitor cells (hMSC) is principally sufficient to shift the differentiation potential in the direction of adipogenic. We thus investigated differentiating hMSCs and the mesenchymal stem cell line SCP-1 cultured under osteogenic conditions and stimulated with supra-physiological cortisone levels. The release of active cortisol into the medium was monitored and the influence on cell differentiation analyzed. We revealed an increase in 11ß-HSD1 expression followed by increased reductive activity of the enzyme, thereby inducing a more adipogenic phenotype of the cell models via cortisol with negative effects on osteogenesis. Through inhibition experiments with the specific inhibitor 10 j, we proved the enzyme specificity for cortisol synthesis and adipogenic differentiation. Increased expression of 11ß-HSD1 followed by higher cortisol levels might thus explain bone marrow adiposity followed by reduced bone quality and stability in old age or in situations of supra-physiological glucocorticoid exposure.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Adipogenia , Hidrocortisona/biossíntese , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Adipogenia/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Cromatografia Líquida , Cortisona/metabolismo , Cortisona/farmacologia , Inibidores Enzimáticos/farmacologia , Regulação Enzimológica da Expressão Gênica , Humanos , Hidrocortisona/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese/fisiologia , Espectrometria de Massas em Tandem
18.
Cell Death Dis ; 12(1): 122, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33495447

RESUMO

The term micro-heterogeneity refers to non-genetic cell to cell variability observed in a bell-shaped distribution of the expression of a trait within a population. The contribution of micro-heterogeneity to physiology and pathology remains largely uncharacterised. To address such an issue, we investigated the impact of heterogeneity in skeletal muscle fibro/adipogenic progenitors (FAPs) isolated from an animal model of Duchenne muscular dystrophy (DMD), the mdx mouse. FAPs play an essential role in muscle homoeostasis. However, in pathological conditions or ageing, they are the source of intramuscular infiltrations of fibrotic or adipose tissue. By applying a multiplex flow cytometry assay, we characterised and purified from mdx muscles two FAP cell states expressing different levels of SCA-1. The two cell states are morphologically identical and repopulate each other after several growth cycles. However, they differ in their in vitro behaviour. Cells expressing higher levels of SCA-1 (SCA1-High-FAPs) differentiate more readily into adipocytes while, when exposed to a fibrogenic stimulation, increase the expression of Col1a1 and Timp1 mRNA. A transcriptomic analysis confirmed the adipogenic propensity of SCA1-High-FAPs. In addition, SCA1-High-FAPs proliferate more extensively ex vivo and display more proliferating cells in dystrophic muscles in comparison to SCA1-Low-FAPs. Adipogenesis of both FAP cell states is inhibited in vitro by leucocytes from young dystrophic mice, while leucocytes isolated from aged dystrophic mice are less effective in limiting the adipogenesis of SCA1-High-FAPs suggesting a differential regulatory effect of the microenvironment on micro-heterogeneity. Our data suggest that FAP micro-heterogeneity is modulated in pathological conditions and that this heterogeneity in turn may impact on the behaviour of interstitial mesenchymal cells in genetic diseases.


Assuntos
Adipogenia/fisiologia , Antígenos Ly/metabolismo , Proteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Animais , Diferenciação Celular , Camundongos
19.
Commun Biol ; 4(1): 90, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469151

RESUMO

Leucine-rich repeats and immunoglobulin-like domains (LRIG) proteins have been implicated as regulators of growth factor signaling; however, the possible redundancy among mammalian LRIG1, LRIG2, and LRIG3 has hindered detailed elucidation of their physiological functions. Here, we show that Lrig-null mouse embryonic fibroblasts (MEFs) are deficient in adipogenesis and bone morphogenetic protein (BMP) signaling. In contrast, transforming growth factor-beta (TGF-ß) and receptor tyrosine kinase (RTK) signaling appeared unaltered in Lrig-null cells. The BMP signaling defect was rescued by ectopic expression of LRIG1 or LRIG3 but not by expression of LRIG2. Caenorhabditis elegans with mutant LRIG/sma-10 variants also exhibited a lipid storage defect. Human LRIG1 variants were strongly associated with increased body mass index (BMI) yet protected against type 2 diabetes; these effects were likely mediated by altered adipocyte morphology. These results demonstrate that LRIG proteins function as evolutionarily conserved regulators of lipid metabolism and BMP signaling and have implications for human disease.


Assuntos
Metabolismo dos Lipídeos/fisiologia , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Adipogenia/fisiologia , Adulto , Idoso , Animais , Índice de Massa Corporal , Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas Morfogenéticas Ósseas/fisiologia , Caenorhabditis elegans , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Fibroblastos/metabolismo , Humanos , Masculino , Glicoproteínas de Membrana/fisiologia , Proteínas de Membrana/fisiologia , Camundongos , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Transdução de Sinais/fisiologia
20.
FASEB J ; 35(2): e21304, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33417247

RESUMO

Multidrug resistance protein 4 (Mrp4) is an efflux transporter known to transport several xenobiotics and endogenous molecules. We recently identified that the lack of Mrp4 increases adipose tissue and body weights in mice. However, the role of Mrp4 in adipose tissue physiology are unknown. The current study aimed at characterizing these specific roles of Mrp4 using wild-type (WT) and knockout (Mrp4-/- ) mice. Our studies determined that Mrp4 is expressed in mouse adipose tissue and that the lack of Mrp4 expression is associated with adipocyte hypertrophy. Furthermore, the lack of Mrp4 increased blood glucose and leptin levels, and impaired glucose tolerance. Additionally, in 3T3-L1 cells and human pre-adipocytes, pharmacological inhibition of Mrp4 increased adipogenesis and altered expression of adipogenic genes. Lack of Mrp4 activity in both of our in vivo and in vitro models leads to increased activation of adipose tissue cAMP response element-binding protein (Creb) and decreased plasma prostaglandin E (PGE) metabolite levels. These changes in Creb activation, coupled with decreased PGE levels, together promoted the observed metabolic phenotype in Mrp4-/- mice. In conclusion, our results indicate that Mrp4 as a novel genetic factor involved in the pathogenesis of metabolic diseases, such as obesity and diabetes.


Assuntos
Diabetes Mellitus/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Obesidade/metabolismo , Adipócitos/metabolismo , Adipogenia/genética , Adipogenia/fisiologia , Animais , Western Blotting , Calorimetria , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Diabetes Mellitus/genética , Humanos , Camundongos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Obesidade/genética , RNA-Seq
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