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1.
Nat Rev Mol Cell Biol ; 25(4): 270-289, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38086922

RESUMO

The prevalence of obesity and associated chronic diseases continues to increase worldwide, negatively impacting on societies and economies. Whereas the association between excess body weight and increased risk for developing a multitude of diseases is well established, the initiating mechanisms by which weight gain impairs our metabolic health remain surprisingly contested. In order to better address the myriad of disease states associated with obesity, it is essential to understand adipose tissue dysfunction and develop strategies for reinforcing adipocyte health. In this Review we outline the diverse physiological functions and pathological roles of human white adipocytes, examining our current knowledge of why white adipocytes are vital for systemic metabolic control, yet poorly adapted to our current obesogenic environment.


Assuntos
Adipócitos Brancos , Obesidade , Humanos , Adipócitos Brancos/metabolismo , Adipócitos Brancos/patologia , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia
2.
Int J Biol Macromol ; 257(Pt 1): 128296, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38000580

RESUMO

In recent years, the incidence of obesity has gradually increased due to high calorie diets and lack of exercise. Reducing energy intake or increasing energy expenditure is the most effective way to promote weight loss and reduce lipid levels. Activated beige adipocytes can increase energy consumption in the body, and inducing conversion of white adipocytes to brown can prevent and treat obesity. Taraxacum mongolicum polysaccharide (TMP) is a plant polysaccharide that has been widely used for its anti-tumour and antioxidant properties. However, little is known about the role of TMP in the browning of sheep white adipose tissue. The aim of this study was to explore the potential mechanism of TMP and miR-134-3p in regulating the browning of sheep white adipocytes, as well as the regulatory relationship between TMP and miR-134-3p. Our results showed that TMP had a positive regulatory effect on the proliferation and browning of sheep white adipocytes. In addition, miR-134-3p significantly inhibited browning activity and AKT/GSK-3ß signalling. Importantly, we found that TMP function required miR-134-3p mediation in the browning of sheep white adipocytes. Overall, our results suggested that TMP recruited beige adipocytes by regulating AKT/GSK-3ß signalling via miR-134-3p.


Assuntos
MicroRNAs , Taraxacum , Animais , Ovinos , Adipócitos Brancos/patologia , Glicogênio Sintase Quinase 3 beta , Proteínas Proto-Oncogênicas c-akt , MicroRNAs/genética , Obesidade/etiologia , Tecido Adiposo Branco/patologia
3.
Sci Rep ; 12(1): 1659, 2022 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-35102236

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) patients display distinct phenotypes of cachexia development, with either adipose tissue loss preceding skeletal muscle wasting or loss of only adipose tissue. Activin A levels were measured in serum and analyzed in tumor specimens of both a cohort of Stage IV PDAC patients and the genetically engineered KPC mouse model. Our data revealed that serum activin A levels were significantly elevated in Stage IV PDAC patients in comparison to age-matched non-cancer patients. Little is known about the role of activin A in adipose tissue wasting in the setting of PDAC cancer cachexia. We established a correlation between elevated activin A and remodeling of visceral adipose tissue. Atrophy and fibrosis of visceral adipose tissue was examined in omental adipose tissue of Stage IV PDAC patients and gonadal adipose tissue of an orthotopic mouse model of PDAC. Remarkably, white visceral adipose tissue from both PDAC patients and mice exhibited decreased adipocyte diameter and increased fibrotic deposition. Strikingly, expression of thermogenic marker UCP1 in visceral adipose tissues of PDAC patients and mice remained unchanged. Thus, we propose that activin A signaling could be relevant to the acceleration of visceral adipose tissue wasting in PDAC-associated cachexia.


Assuntos
Ativinas/metabolismo , Adipócitos Brancos/metabolismo , Adiposidade , Carcinoma Ductal Pancreático/metabolismo , Subunidades beta de Inibinas/metabolismo , Gordura Intra-Abdominal/metabolismo , Neoplasias Pancreáticas/metabolismo , Ativinas/genética , Adipócitos Brancos/patologia , Animais , Atrofia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Estudos de Casos e Controles , Linhagem Celular , Fibrose , Humanos , Subunidades beta de Inibinas/genética , Gordura Intra-Abdominal/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Estadiamento de Neoplasias , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Transdução de Sinais , Proteína Desacopladora 1/metabolismo
4.
Int J Mol Sci ; 22(22)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34830238

RESUMO

Leptin is a small molecule protein secreted by adipocytes, which can promote white fat browning through activating the hypothalamic nervous system and inhibiting downstream signaling pathways. Moreover, white fat browning has been proven to alleviate fat tissue fibrosis. This study explores the mechanism of leptin in regulating adipose tissue fibrosis and white fat browning. After treating mice with leptin, we screened out the recombinant integrin alpha 5 (ITGA5) through proteomics sequencing, which may play a role in adipose tissue fibrosis. Through real-time quantitative PCR (qPCR), western blotting (WB), hematoxylin-eosin (HE) staining, Masson's trichrome, immunofluorescence, immunohistochemistry, etc., the results showed that after leptin treated adipocytes, the expression of fibrosis-related genes and ITGA5 was significantly down-regulated in adipocytes. We constructed fibrosis model through transforming growth factor-ß (TGF-ß) and a high-fat diet (HFD), and treated with ITGA5 overexpression vector and interference fragments. The results indicated the expression of fibrosis-related genes were significantly down-regulated after interfering with ITGA5. After treating adipocytes with wortmannin, fibrosis-related gene expression was inhibited after overexpression of ITGA5. Moreover, after injecting mice with leptin, we also found that leptin significantly up-regulated the expression of adipose tissue browning-related genes. Overall, our research shows that leptin can inhibit the activation of phosphatidylinositol 3 kinase (PI3K)-protein kinase B (AKT) signaling pathway by reducing the expression of ITGA5, which could alleviate adipose tissue fibrosis, and further promote white fat browning. Our research provides a theoretical basis for further research on the effect of leptin in fibrosis-related adipose tissue metabolism.


Assuntos
Adipócitos Marrons/efeitos dos fármacos , Adipócitos Brancos/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Integrinas/genética , Leptina/farmacologia , Obesidade/genética , Adipócitos Marrons/metabolismo , Adipócitos Marrons/patologia , Adipócitos Brancos/metabolismo , Adipócitos Brancos/patologia , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Animais , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo III/genética , Colágeno Tipo III/metabolismo , Colágeno Tipo VI/genética , Colágeno Tipo VI/metabolismo , Dieta Hiperlipídica/efeitos adversos , Fibrose , Regulação da Expressão Gênica , Integrinas/antagonistas & inibidores , Integrinas/metabolismo , Leptina/metabolismo , Masculino , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/etiologia , Obesidade/patologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Wortmanina/farmacologia
5.
Biochem Pharmacol ; 192: 114723, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34364887

RESUMO

Both obesity and aging are associated with the development of metabolic diseases such as type 2 diabetes and cardiovascular disease. Chronic low-grade inflammation of adipose tissue is one of the mechanisms implicated in the progression of these diseases. Obesity and aging trigger adipose tissue alterations that ultimately lead to a pro-inflammatory phenotype of the adipose tissue-resident immune cells. Obesity and aging also share other features such as a higher visceral vs. subcutaneous adipose tissue ratio and a decreased lifespan. Here, we review the common characteristics of obesity and aging and the alterations in white adipose tissue and resident immune cells. We focus on the adipose tissue metabolic derangements in obesity and aging such as inflammation and adipose tissue remodeling.


Assuntos
Adipócitos Brancos/imunologia , Tecido Adiposo Branco/imunologia , Envelhecimento/imunologia , Distribuição da Gordura Corporal/métodos , Obesidade/imunologia , Adipócitos Brancos/metabolismo , Adipócitos Brancos/patologia , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Humanos , Gordura Intra-Abdominal/imunologia , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/patologia , Obesidade/metabolismo , Obesidade/patologia
6.
Cell Death Dis ; 12(7): 666, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215724

RESUMO

High-mobility group box 2 (HMGB2) is an abundant, chromatin-associated protein that plays an essential role in the regulation of transcription, cell proliferation, differentiation, and tumorigenesis. However, the underlying mechanism of HMGB2 in adipogenesis remains poorly known. Here, we provide evidence that HMGB2 deficiency in preadipocytes impedes adipogenesis, while overexpression of HMGB2 increases the potential for adipogenic differentiation. Besides, depletion of HMGB2 in vivo caused the decrease in body weight, white adipose tissue (WAT) mass, and adipocyte size. Consistently, the stromal vascular fraction (SVF) of adipose tissue derived from hmgb2-/- mice presented impaired adipogenesis. When hmgb2-/- mice were fed with high-fat diet (HFD), the body size, and WAT mass were increased, but at a lower rate. Mechanistically, HMGB2 mediates adipogenesis via enhancing expression of C/EBPß by binding to its promoter at "GGGTCTCAC" specifically during mitotic clonal expansion (MCE) stage, and exogenous expression of C/EBPß can rescue adipogenic abilities of preadipocytes in response to HMGB2 inhibition. In general, our findings provide a novel mechanism of HMGB2-C/EBPß axis in adipogenesis and a potential therapeutic target for obesity.


Assuntos
Adipócitos Brancos/metabolismo , Adipogenia , Tecido Adiposo Branco/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteína HMGB2/metabolismo , Mitose , Obesidade/metabolismo , Regiões Promotoras Genéticas , Adipócitos Brancos/patologia , Tecido Adiposo Branco/patologia , Animais , Sítios de Ligação , Proteína beta Intensificadora de Ligação a CCAAT/genética , Células Cultivadas , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Proteína HMGB2/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Obesidade/patologia , Transdução de Sinais , Aumento de Peso
7.
Toxicol Appl Pharmacol ; 413: 115393, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33412187

RESUMO

Prolonged treatment with rifampicin (RFP), a first-line antibacterial agent used in the treatment of drug-sensitive tuberculosis, may cause various side effects, including metabolic disorders. The nuclear factor (erythroid-derived 2)-like 2 (NFE2L2, also known as NRF2) plays an essential regulatory role in cellular adaptive responses to stresses via the antioxidant response element (ARE). Our previous studies discovered that NRF2 regulates the expression of CCAAT-enhancer-binding protein ß (Cebpb) and peroxisome proliferator-activated receptor gamma (Pparg) in the process of adipogenesis. Here, we found that prolonged RFP treatment in adult male mice fed a high-fat diet developed insulin resistance, but reduced fat accumulation and decreased expression of multiple adipogenic genes in white adipose tissues. In 3 T3-L1 preadipocytes, RFP reduced the induction of Cebpb, Pparg and Cebpa at mRNA and protein levels in the early and/or later stage of hormonal cocktail-induced adipogenesis. Mechanistic investigations demonstrated that RFP inhibits NRF2-ARE luciferase reporter activity and expression of NRF2 downstream genes under normal culture condition and in the early stage of adipogenesis in 3 T3-L1 preadipocytes, suggesting that RFP can disturb adipogenic differentiation via NRF2-ARE interference. Taken together, we demonstrate a potential mechanism that RFP impairs adipose function by which RFP likely inhibits NRF2-ARE pathway and thereby interrupts its downstream adipogenic transcription network.


Assuntos
Adipócitos Brancos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Antibióticos Antituberculose/toxicidade , Elementos de Resposta Antioxidante , Fator 2 Relacionado a NF-E2/metabolismo , Obesidade/metabolismo , Rifampina/toxicidade , Células 3T3-L1 , Adipócitos Brancos/metabolismo , Adipócitos Brancos/patologia , Adipogenia/genética , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Tecido Adiposo Branco/fisiopatologia , Adiposidade/efeitos dos fármacos , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Obesidade/genética , Obesidade/patologia , Obesidade/fisiopatologia , Transdução de Sinais , Transcrição Gênica
8.
Am J Physiol Regul Integr Comp Physiol ; 320(4): R471-R487, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33470901

RESUMO

Previous studies indicate that oxytocin (OT) administration reduces body weight in high-fat diet (HFD)-induced obese (DIO) rodents through both reductions in food intake and increases in energy expenditure. We recently demonstrated that chronic hindbrain [fourth ventricular (4V)] infusions of OT evoke weight loss in DIO rats. Based on these findings, we hypothesized that chronic 4V OT would elicit weight loss in DIO mice. We assessed the effects of 4V infusions of OT (16 nmol/day) or vehicle over 28 days on body weight, food intake, and body composition. OT reduced body weight by approximately 4.5% ± 1.4% in DIO mice relative to OT pretreatment body weight (P < 0.05). These effects were associated with reduced adiposity and adipocyte size [inguinal white adipose tissue (IWAT)] (P < 0.05) and attributed, in part, to reduced energy intake (P < 0.05) at a dose that did not increase kaolin intake (P = NS). OT tended to increase uncoupling protein-1 expression in IWAT (0.05 < P < 0.1) suggesting that OT stimulates browning of WAT. To assess OT-elicited changes in brown adipose tissue (BAT) thermogenesis, we examined the effects of 4V OT on interscapular BAT temperature (TIBAT). 4V OT (1 µg) elevated TIBAT at 0.75 (P = 0.08), 1, and 1.25 h (P < 0.05) postinjection; a higher dose (5 µg) elevated TIBAT at 0.75-, 1-, 1.25-, 1.5-, 1.75- (P < 0.05), and 2-h (0.05 < P < 0.1) postinjection. Together, these findings support the hypothesis that chronic hindbrain OT treatment evokes sustained weight loss in DIO mice by reducing energy intake and increasing BAT thermogenesis at a dose that is not associated with evidence of visceral illness.


Assuntos
Fármacos Antiobesidade/administração & dosagem , Dieta Hiperlipídica , Obesidade/tratamento farmacológico , Ocitocina/administração & dosagem , Rombencéfalo/efeitos dos fármacos , Redução de Peso/efeitos dos fármacos , Adipócitos Marrons/efeitos dos fármacos , Adipócitos Marrons/metabolismo , Adipócitos Marrons/patologia , Adipócitos Brancos/efeitos dos fármacos , Adipócitos Brancos/metabolismo , Adipócitos Brancos/patologia , Adiposidade/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Energia/efeitos dos fármacos , Infusões Intraventriculares , Leptina/sangue , Masculino , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Obesidade/patologia , Obesidade/fisiopatologia , Rombencéfalo/fisiopatologia , Termogênese/efeitos dos fármacos , Proteína Desacopladora 1/metabolismo
9.
FEBS J ; 288(12): 3628-3646, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32621398

RESUMO

Brown and brite adipocytes contribute to energy expenditure through nonshivering thermogenesis. Though these cell types are thought to arise primarily from the de novo differentiation of precursor cells, their abundance is also controlled through the transdifferentiation of mature white adipocytes. Here, we review recent advances in our understanding of the regulation of white-to-brown transdifferentiation, as well as the conversion of brown and brite adipocytes to dormant, white-like fat cells. Converting mature white adipocytes into brite cells or reactivating dormant brown and brite adipocytes has emerged as a strategy to ameliorate human metabolic disorders. We analyze the evidence of learning from mice and how they translate to humans to ultimately scrutinize the relevance of this concept. Moreover, we estimate that converting a small percentage of existing white fat mass in obese subjects into active brite adipocytes could be sufficient to achieve meaningful benefits in metabolism. In conclusion, novel browning agents have to be identified before adipocyte transdifferentiation can be realized as a safe and efficacious therapy.


Assuntos
Adipócitos Bege/metabolismo , Adipócitos Marrons/metabolismo , Adipócitos Brancos/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Diabetes Mellitus/metabolismo , Obesidade/metabolismo , Acetanilidas/farmacologia , Adipócitos Bege/citologia , Adipócitos Bege/efeitos dos fármacos , Adipócitos Marrons/citologia , Adipócitos Marrons/efeitos dos fármacos , Adipócitos Brancos/efeitos dos fármacos , Adipócitos Brancos/patologia , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/patologia , Animais , Linhagem da Célula/efeitos dos fármacos , Linhagem da Célula/genética , Transdiferenciação Celular/efeitos dos fármacos , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/genética , Diabetes Mellitus/patologia , Drogas em Investigação/farmacologia , Metabolismo Energético/genética , Humanos , Mesilato de Imatinib/farmacologia , Obesidade/tratamento farmacológico , Obesidade/genética , Obesidade/patologia , Roscovitina/farmacologia , Termogênese/genética , Tiazóis/farmacologia
10.
Molecules ; 25(21)2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33139672

RESUMO

Recently, inositols, especially myo-inositol and inositol hexakisphosphate, also known as phytic acid or IP6, with their biological activities received much attention for their role in multiple health beneficial effects. Although their roles in cancer treatment and prevention have been extensively reported, interestingly, they may also have distinctive properties in energy metabolism and metabolic disorders. We review inositols and inositol phosphate metabolism in mammalian cells to establish their biological activities and highlight their potential roles in energy metabolism. These molecules are known to decrease insulin resistance, increase insulin sensitivity, and have diverse properties with importance from cell signaling to metabolism. Evidence showed that inositol phosphates might enhance the browning of white adipocytes and directly improve insulin sensitivity through adipocytes. In addition, inositol pyrophosphates containing high-energy phosphate bonds are considered in increasing cellular energetics. Despite all recent advances, many aspects of the bioactivity of inositol phosphates are still not clear, especially their effects on insulin resistance and alteration of metabolism, so more research is needed.


Assuntos
Adipócitos Brancos/metabolismo , Metabolismo Energético , Fosfatos de Inositol/metabolismo , Resistência à Insulina , Transdução de Sinais , Adipócitos Brancos/patologia , Animais , Humanos
11.
Nat Commun ; 11(1): 5455, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33116140

RESUMO

The expansion of the white adipose tissue (WAT) in obesity goes along with increased mechanical, metabolic and inflammatory stress. How adipocytes resist this stress is still poorly understood. Both in human and mouse adipocytes, the transcriptional co-activators YAP/TAZ and YAP/TAZ target genes become activated during obesity. When fed a high-fat diet (HFD), mice lacking YAP/TAZ in white adipocytes develop severe lipodystrophy with adipocyte cell death. The pro-apoptotic factor BIM, which is downregulated in adipocytes of obese mice and humans, is strongly upregulated in YAP/TAZ-deficient adipocytes under HFD, and suppression of BIM expression reduces adipocyte apoptosis. In differentiated adipocytes, TNFα and IL-1ß promote YAP/TAZ nuclear translocation via activation of RhoA-mediated actomyosin contractility and increase YAP/TAZ-mediated transcriptional regulation by activation of c-Jun N-terminal kinase (JNK) and AP-1. Our data indicate that the YAP/TAZ signaling pathway may be a target to control adipocyte cell death and compensatory adipogenesis during obesity.


Assuntos
Adipócitos Brancos/metabolismo , Adipócitos Brancos/patologia , Obesidade/metabolismo , Obesidade/patologia , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adipogenia , Animais , Proteína 11 Semelhante a Bcl-2/metabolismo , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Morte Celular , Células Cultivadas , Dieta Hiperlipídica , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Transativadores/deficiência , Transativadores/genética , Transativadores/metabolismo , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas de Sinalização YAP
12.
Arterioscler Thromb Vasc Biol ; 40(9): 2227-2243, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32640901

RESUMO

OBJECTIVE: Perivascular adipose tissue (PVAT) surrounding arteries supports healthy vascular function. During obesity, PVAT loses its vasoprotective effect. We study pathological conversion of PVAT, which involves molecular changes in protein profiles and functional changes in adipocytes. Approach and Results: C57BL6/J mice were fed a 60% high-fat diet for 12 weeks or a cardioprotective 30% calorie-restricted diet for 5 weeks. Proteomic analysis identified PVAT as a molecularly distinct adipose depot, and novel markers for thermogenic adipocytes, such as GRP75 (stress-70 protein, mitochondrial), were identified. High-fat diet increased the similarity of protein signatures in PVAT and brown adipose, suggesting activation of a conserved whitening pathway. The whitening phenotype was characterized by suppression of UCP1 (uncoupling protein 1) and increased lipid deposition, leptin, and inflammation, and specifically in PVAT, elevated Notch signaling. Conversely, PVAT from calorie-restricted mice had decreased Notch signaling and less lipid. Using the Adipoq-Cre strain, we constitutively activated Notch1 signaling in adipocytes, which phenocopied the changes in PVAT caused by a high-fat diet, even on a standard diet. Preadipocytes from mouse PVAT expressed Sca1, CD140a, Notch1, and Notch2, but not CD105, showing differences compared with preadipocytes from other depots. Inhibition of Notch signaling during differentiation of PVAT-derived preadipocytes reduced lipid deposition and adipocyte marker expression. CONCLUSIONS: PVAT shares features with other adipose depots, but has a unique protein signature that is regulated by dietary stress. Increased Notch signaling in PVAT is sufficient to initiate the pathological conversion of PVAT by promoting adipogenesis and lipid accumulation and may thus prime the microenvironment for vascular disease.


Assuntos
Adipócitos Brancos/metabolismo , Adipogenia , Tecido Adiposo Branco/metabolismo , Lipogênese , Obesidade/metabolismo , Receptores Notch/metabolismo , Adipócitos Brancos/patologia , Tecido Adiposo Branco/patologia , Adiposidade , Animais , Ataxina-1/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Restrição Calórica , Dieta Hiperlipídica , Modelos Animais de Doenças , Endoglina/metabolismo , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade/genética , Obesidade/patologia , Fenótipo , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Proteômica , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptor Notch2/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores Notch/genética , Transdução de Sinais
13.
Int J Gynecol Pathol ; 39(4): 379-383, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32515922

RESUMO

The human uterine cervix consists mainly of epithelium and stroma, including smooth muscle cells and fibrovascular tissues. Fat cells in the uterine cervix have been rarely reported, and the only previous research article has shown that intracervical adipocytes are unrelated to clinical factors. The aim of this study was to investigate the frequency of fat cells in the uterine cervix, as well as to evaluate the relationship between intracervical adipocytes and clinicopathologic factors. We retrospectively selected 405 cases in Japanese women who received cervical conization at our hospital between 2003 and 2017. Cervical conization was not performed during pregnancy or within 1 yr after childbirth. The prepared histologic specimens for pathologic diagnosis were available in all cases. Age, menopause status, body mass index, gravidity, and parity were selected clinical factors, which were obtained in 214 patients. The mean patient age was 42 yr (range, 22-80 yr). Intracervical white adipocytes were observed in 13% of patients (53/405), with no brown adipocytes detected. The existence of intracervical adipocytes was significantly correlated to older age (P<0.0001), postmenopause status (P<0.0001), and higher body mass index (P=0.0018). Intracervical adipocytes might undergo adipocytic metaplasia from cervical stromal cells in accordance with aging, postmenopause status, or weight gain. Our result also suggest that cervical malignancy involving fat cells does not necessarily imply parametrial invasion.


Assuntos
Adipócitos Brancos/patologia , Conização , Metaplasia/patologia , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Colo do Útero/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias , Pós-Menopausa , Estudos Retrospectivos , Adulto Jovem
14.
Sci Rep ; 10(1): 6846, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321999

RESUMO

Obstructive sleep apnea (OSA) is a common sleep disorder associated with obesity. Emerging evidence suggest that OSA increases the risk of cardiovascular morbidity and mortality partly via accelerating the process of cellular aging. Thus, we sought to examine the effects of intermittent hypoxia (IH), a hallmark of OSA, on senescence in human white preadipocytes. We demonstrate that chronic IH is associated with an increased generation of mitochondrial reactive oxygen species along with increased prevalence of cells with nuclear localization of γH2AX & p16. A higher prevalence of cells positive for senescence-associated ß-galactosidase activity was also evident with chronic IH exposure. Intervention with aspirin, atorvastatin or renin-angiotensin system (RAS) inhibitors effectively attenuated IH-mediated senescence-like phenotype. Importantly, the validity of in vitro findings was confirmed by examination of the subcutaneous abdominal adipose tissue which showed that OSA patients had a significantly higher percentage of cells with nuclear localization of γH2AX & p16 than non-OSA individuals (20.1 ± 10.8% vs. 10.3 ± 2.7%, Padjusted < 0.001). Furthermore, the frequency of dual positive γH2AX & p16 nuclei in adipose tissue of OSA patients receiving statin, aspirin, and/or RAS inhibitors was comparable to non-OSA individuals. This study identifies chronic IH as a trigger of senescence-like phenotype in preadipocytes. Together, our data suggest that OSA may be considered as a senescence-related disorder.


Assuntos
Adipócitos Brancos/metabolismo , Senescência Celular , Apneia Obstrutiva do Sono/metabolismo , Adipócitos Brancos/patologia , Hipóxia Celular , Doença Crônica , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Histonas/metabolismo , Humanos , Masculino , Espécies Reativas de Oxigênio/metabolismo , Apneia Obstrutiva do Sono/patologia
15.
Clin Sci (Lond) ; 134(7): 921-939, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32239178

RESUMO

Maternal obesity determines obesity and metabolic diseases in the offspring. The white adipose tissue (WAT) orchestrates metabolic pathways, and its dysfunction contributes to metabolic disorders in a sex-dependent manner. Here, we tested if sex differences influence the molecular mechanisms of metabolic programming of WAT in offspring of obese dams. To this end, maternal obesity was induced with high-fat diet (HFD) and the offspring were studied at an early phase [postnatal day 21 (P21)], a late phase (P70) and finally P120. In the early phase we found a sex-independent increase in WAT in offspring of obese dams using magnetic resonance imaging (MRI), which was more pronounced in females than males. While the adipocyte size increased in both sexes, the distribution of WAT differed in males and females. As mechanistic hints, we identified an inflammatory response in females and a senescence-associated reduction in the preadipocyte factor DLK in males. In the late phase, the obese body composition persisted in both sexes, with a partial reversal in females. Moreover, female offspring recovered completely from both the adipocyte hypertrophy and the inflammatory response. These findings were linked to a dysregulation of lipolytic, adipogenic and stemness-related markers as well as AMPKα and Akt signaling. Finally, the sex-dependent metabolic programming persisted with sex-specific differences in adipocyte size until P120. In conclusion, we do not only provide new insights into the molecular mechanisms of sex-dependent metabolic programming of WAT dysfunction, but also highlight the sex-dependent development of low- and high-grade pathogenic obesity.


Assuntos
Adipócitos Brancos/metabolismo , Adipogenia , Tecido Adiposo Branco/metabolismo , Adiposidade , Dieta Hiperlipídica , Metabolismo Energético , Obesidade Materna/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Adipócitos Brancos/patologia , Adipogenia/genética , Tecido Adiposo Branco/patologia , Tecido Adiposo Branco/fisiopatologia , Adiposidade/genética , Fenômenos Fisiológicos da Nutrição Animal , Animais , Tamanho Celular , Modelos Animais de Doenças , Metabolismo Energético/genética , Feminino , Regulação da Expressão Gênica , Hipertrofia , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Camundongos Endogâmicos C57BL , Estado Nutricional , Obesidade Materna/genética , Obesidade Materna/patologia , Obesidade Materna/fisiopatologia , Gravidez , Caracteres Sexuais , Fatores Sexuais , Transdução de Sinais , Fatores de Tempo
16.
Biomolecules ; 10(3)2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32131495

RESUMO

Biliverdin reductase (BVR) is an enzymatic and signaling protein that has multifaceted roles in physiological systems. Despite the wealth of knowledge about BVR, no data exist regarding its actions in adipocytes. Here, we generated an adipose-specific deletion of biliverdin reductase-A (BVRA) (BlvraFatKO) in mice to determine the function of BVRA in adipocytes and how it may impact adipose tissue expansion. The BlvraFatKO and littermate control (BlvraFlox) mice were placed on a high-fat diet (HFD) for 12 weeks. Body weights were measured weekly and body composition, fasting blood glucose and insulin levels were quantitated at the end of the 12 weeks. The data showed that the percent body fat and body weights did not differ between the groups; however, BlvraFatKO mice had significantly higher visceral fat as compared to the BlvraFlox. The loss of adipocyte BVRA decreased the mitochondrial number in white adipose tissue (WAT), and increased inflammation and adipocyte size, but this was not observed in brown adipose tissue (BAT). There were genes significantly reduced in WAT that induce the browning effect such as Ppara and Adrb3, indicating that BVRA improves mitochondria function and beige-type white adipocytes. The BlvraFatKO mice also had significantly higher fasting blood glucose levels and no changes in plasma insulin levels, which is indicative of decreased insulin signaling in WAT, as evidenced by reduced levels of phosphorylated AKT (pAKT) and Glut4 mRNA. These results demonstrate the essential role of BVRA in WAT in insulin signaling and adipocyte hypertrophy.


Assuntos
Adipócitos Brancos/enzimologia , Tecido Adiposo Branco/enzimologia , Mitocôndrias/metabolismo , Obesidade/enzimologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Adipócitos Brancos/patologia , Tecido Adiposo Branco/patologia , Animais , Técnicas de Inativação de Genes , Hipertrofia , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Mitocôndrias/patologia , Obesidade/genética , Obesidade/patologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , PPAR alfa/genética , PPAR alfa/metabolismo , Receptores Adrenérgicos beta 3/genética , Receptores Adrenérgicos beta 3/metabolismo
17.
Microvasc Res ; 130: 104003, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32199946

RESUMO

OBJECTIVE: This study aimed to determine the effects of physical exercise on the angio-adaptive response in adipose tissue following weight loss in a mouse model of diet-induced obesity. We hypothesized that physical exercise stimulates angiogenesis through the regulation of Vascular endothelial growth factor-A (VEGF-A) pro-/Thrombospondin-1 (TSP-1) anti-angiogenic signal under the control of the Murine double-minute 2/Forkhead box Os (Mdm2/FoxOs) axis, as reported in skeletal muscle. METHODS: We studied the effects of 7 weeks-voluntary exercise (Ex) in C57Bl/6 control or diet-induced obese (HFS) mice on vascularization of white adipose tissue (AT). RESULTS: Diet-induced obese sedentary (HFSsed) mice presented a powerful angiostatic control in all adipose tissues, under FoxOs protein regulation, leading to capillary rarefaction. Exercise increased expression of Mdm2, repressing the angiostatic control in favor of adipose vascular regrowth in normal chow (NCex) and HFSex mice. This phenomenon was associated with adipocytes microenvironment improvement, such as decreased adipocytes hypertrophy and adipose tissue inflammation. In addition, adipose angiogenesis stimulation by exercise through Mdm2 pro-angiogenic action, improved visceral adipose insulin sensitivity, activated browning process within subcutaneous adipose tissue (ScWAT) and decreased ectopic fat deposition (muscle, heart and liver) in obese HFSex mice. The overall result of this approach of therapy by physical exercise is an improvement of all systemic cardiometabolic parameters. CONCLUSIONS: These data demonstrated the therapeutic efficacy of physical exercise against obesity-associated pathologies, and also offer new prospects for molecular therapies targeting the adipose angio-adaptation in obese humans.


Assuntos
Adipócitos Brancos/metabolismo , Tecido Adiposo Branco/irrigação sanguínea , Tecido Adiposo Branco/metabolismo , Dieta Hiperlipídica , Terapia por Exercício , Neovascularização Fisiológica , Obesidade/terapia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Adipócitos Marrons/metabolismo , Adipócitos Marrons/patologia , Adipócitos Brancos/patologia , Tecido Adiposo Branco/patologia , Animais , Microambiente Celular , Modelos Animais de Doenças , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O3/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Obesidade/patologia , Obesidade/fisiopatologia , Transdução de Sinais , Trombospondina 1/metabolismo , Técnicas de Cultura de Tecidos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Redução de Peso
18.
Nat Commun ; 11(1): 481, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980643

RESUMO

Vascular senescence is thought to play a crucial role in an ageing-associated decline of organ functions; however, whether vascular senescence is causally implicated in age-related disease remains unclear. Here we show that endothelial cell (EC) senescence induces metabolic disorders through the senescence-associated secretory phenotype. Senescence-messaging secretomes from senescent ECs induced a senescence-like state and reduced insulin receptor substrate-1 in adipocytes, which thereby impaired insulin signaling. We generated EC-specific progeroid mice that overexpressed the dominant negative form of telomeric repeat-binding factor 2 under the control of the Tie2 promoter. EC-specific progeria impaired systemic metabolic health in mice in association with adipose tissue dysfunction even while consuming normal chow. Notably, shared circulation with EC-specific progeroid mice by parabiosis sufficiently transmitted the metabolic disorders into wild-type recipient mice. Our data provides direct evidence that EC senescence impairs systemic metabolic health, and thus establishes EC senescence as a bona fide risk for age-related metabolic disease.


Assuntos
Senescência Celular , Resistência à Insulina , Progéria/metabolismo , Progéria/patologia , Adipócitos Brancos/metabolismo , Adipócitos Brancos/patologia , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Animais , Senescência Celular/genética , Senescência Celular/fisiologia , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Resistência à Insulina/genética , Resistência à Insulina/fisiologia , Interleucina-1alfa/metabolismo , Camundongos , Camundongos Transgênicos , Estresse Oxidativo , Progéria/genética , Regiões Promotoras Genéticas , Receptor TIE-2/genética , Transdução de Sinais , Proteína 2 de Ligação a Repetições Teloméricas/deficiência , Proteína 2 de Ligação a Repetições Teloméricas/genética , Proteína 2 de Ligação a Repetições Teloméricas/metabolismo
19.
Am J Physiol Cell Physiol ; 318(1): C63-C72, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31596606

RESUMO

Endocrine-disrupting chemicals interact with transcription factors essential for adipocyte differentiation. Exposure to endocrine-disrupting chemicals corresponds with elevated risks of obesity, but the effects of these compounds on human cells remain largely undefined. Widespread use of bisphenol AF (BPAF) as a bisphenol A (BPA) alternative in the plastics industry presents unknown health risks. To this end, we discovered that BPAF interferes with the metabolic function of mature human adipocytes. Although 4-day exposures to BPAF accelerated adipocyte differentiation, we observed no effect on mature fat cell marker genes. Additional gene and protein expression analysis showed that BPAF treatment during human adipocyte differentiation failed to suppress the proinflammatory transcription factor STAT1. Microscopy and respirometry experiments demonstrated that BPAF impaired mitochondrial function and structure. To test the hypothesis that BPAF fosters vulnerabilities to STAT1 activation, we treated mature adipocytes previously exposed to BPAF with interferon-γ (IFNγ). BPAF increased IFNγ activation of STAT1 and exposed mitochondrial vulnerabilities that disrupt adipocyte lipid and carbohydrate metabolism. Collectively, our data establish that BPAF activates inflammatory signaling pathways that degrade metabolic activity in human adipocytes. These findings suggest how the BPA alternative BPAF contributes to metabolic changes that correspond with obesity.


Assuntos
Adipócitos Brancos/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Metabolismo Energético/efeitos dos fármacos , Paniculite/induzido quimicamente , Fenóis/toxicidade , Adipócitos Brancos/metabolismo , Adipócitos Brancos/patologia , Adipogenia/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Células Cultivadas , Regulação da Expressão Gênica , Humanos , Interferon gama/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , PPAR gama/genética , PPAR gama/metabolismo , Paniculite/metabolismo , Paniculite/patologia , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais
20.
Endocr J ; 67(1): 21-30, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31495810

RESUMO

Glucocorticoids play a critical role in the regulation of homeostasis, including metabolism. In patients with Cushing's syndrome, chronic glucocorticoid excess disrupts physiological internal milieu, resulting in central obesity, muscle atrophy, fatty liver, and insulin resistance. However, the relationship among various metabolic effects of glucocorticoids remains unknown. In the present study, we studied a male mouse model of Cushing's syndrome and indicated that glucocorticoid excess alters metabolic phenotype and body composition involving possible communication among skeletal muscle, liver, and adipose tissue.


Assuntos
Tecido Adiposo/metabolismo , Composição Corporal , Síndrome de Cushing/metabolismo , Fígado/metabolismo , Músculos Paraespinais/metabolismo , Adipócitos Brancos/patologia , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Tecido Adiposo Branco/diagnóstico por imagem , Tecido Adiposo Branco/patologia , Corticosteroides/toxicidade , Alanina/metabolismo , Alanina Transaminase/metabolismo , Animais , Glicemia/metabolismo , Corticosterona/toxicidade , Síndrome de Cushing/patologia , Modelos Animais de Doenças , Fatores de Crescimento de Fibroblastos/metabolismo , Glucocorticoides/metabolismo , Insulina/metabolismo , Resistência à Insulina , Gordura Intra-Abdominal/diagnóstico por imagem , Gordura Intra-Abdominal/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Camundongos , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculos Paraespinais/diagnóstico por imagem , Músculos Paraespinais/patologia , Triglicerídeos/metabolismo , Microtomografia por Raio-X
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