RESUMO
Xenopus has been a powerful model organism for understanding vertebrate development and disease for over a hundred years. While experimental analysis and dissection techniques of the embryo have been well documented, descriptions of adult Xenopus structures and organs, together with techniques for working with adults, have not been updated to take into consideration the requirements of such modern approaches as quantitative proteomics and single-cell transcriptomics. The cell-type and gene-centric perspectives require contrasting observations in embryonic stages to those in adult tissues. The organs of the larva undergo significant changes in their overall structure, morphology, and anatomical location all along the larval to adult transition, most notably during massive metamorphosis remodeling. Establishing robust standards for organ identification and dissection is crucial to ensure datasets resulting from studies performed at different laboratories can be consistent. The present protocol identifies six of the organs in the adult Xenopus, demonstrating methods for dissection and sampling of the heart ventricle, liver, fat body, pancreas, paired kidney, and skin of the adult Xenopus. Depending on the preservation methods, the dissected organs can be used for quantitative proteomics, single cell/nuclei transcriptomics, in situ hybridization, immunohistochemistry, histology, etc. This protocol aims to standardize tissue sampling and facilitate multi-lab investigations of the adult organ systems.
Assuntos
Dissecação , Fígado , Animais , Xenopus laevis , Tecido Adiposo , Hibridização In Situ , LarvaRESUMO
Natural killer T (NKT) cell are members of the innate-like T lymphocytes and recognizes lipid antigens presented by CD1d-expressing cells. Obesity-associated inflammation in adipose tissue (AT) leads to metabolic dysfunction, including insulin resistance. When cellular communication is properly regulated among AT-residing immune cells and adipocytes during inflammation, a favorable balance of Th1 and Th2 immune responses is achieved. NKT cells play crucial roles in AT inflammation, influencing the development of diet-induced obesity and insulin resistance. NKT cells interact with CD1d-expressing cells in AT, such as adipocytes, macrophages, and dendritic cells, shaping pro-inflammatory or anti-inflammatory microenvironments with distinct characteristics depending on the antigen-presenting cells. Additionally, CD1d may be involved in the inflammatory process independently of NKT cells. In this mini-review, we provide a brief overview of the current understanding of the interaction between immune cells, focusing on NKT cells and CD1d signaling, which control AT inflammation both in the presence and absence of NKT cells. We aim to enhance our understanding of the mechanisms of obesity-associated diseases.
Assuntos
Resistência à Insulina , Células T Matadoras Naturais , Humanos , Tecido Adiposo , Obesidade , InflamaçãoRESUMO
Pancreatic adipose tissue serves as a crucial structural basis for the development of glycolipid metabolic disorders. Understanding the mechanisms underlying pancreatic adipose tissue infiltration and regulatory strategies is essential for early intervention in glycolipid metabolic disorders. Pancreatic adipose tissue functions as a significant medium linking systemic immune metabolism, while the pancreatic vascular system emerges as a novel target for sensing pancreatic immune responses and maintaining the body's energy homeostasis, collectively participating in the development of glycolipid metabolic disorders. Acupuncture possesses potential effects in modulating the interaction between resident macrophages and adipocytes in the pancreas, leading to the reversible reduction of excessive pancreatic adipose accumulation, with its action being vascular-dependent.
Assuntos
Terapia por Acupuntura , Doenças Metabólicas , Humanos , Tecido Adiposo/metabolismo , Adipócitos/metabolismo , Pâncreas , Doenças Metabólicas/terapia , Doenças Metabólicas/metabolismoRESUMO
Caffeine is a popular ergogenic aid that has a plethora of evidence highlighting its positive effects. A Google Scholar search using the keywords "caffeine" and "exercise" yields over 200,000 results, emphasizing the extensive research on this topic. However, despite the vast amount of available data, it is intriguing that uncertainties persist regarding the effectiveness and safety of caffeine. These include but are not limited to: 1. Does caffeine dehydrate you at rest? 2. Does caffeine dehydrate you during exercise? 3. Does caffeine promote the loss of body fat? 4. Does habitual caffeine consumption influence the performance response to acute caffeine supplementation? 5. Does caffeine affect upper vs. lower body performance/strength differently? 6. Is there a relationship between caffeine and depression? 7. Can too much caffeine kill you? 8. Are there sex differences regarding caffeine's effects? 9. Does caffeine work for everyone? 10. Does caffeine cause heart problems? 11. Does caffeine promote the loss of bone mineral? 12. Should pregnant women avoid caffeine? 13. Is caffeine addictive? 14. Does waiting 1.5-2.0 hours after waking to consume caffeine help you avoid the afternoon "crash?" To answer these questions, we performed an evidence-based scientific evaluation of the literature regarding caffeine supplementation.
Assuntos
Cafeína , Substâncias para Melhoria do Desempenho , Masculino , Gravidez , Humanos , Feminino , Cafeína/farmacologia , Tecido Adiposo , Exercício Físico , Substâncias para Melhoria do Desempenho/farmacologia , Suplementos NutricionaisRESUMO
Perirenal adipose tissue (PRAT) is a unique visceral depot that contains a mixture of brown and white adipocytes. The origin and plasticity of such cellular heterogeneity remains unknown. Here, we combine single-nucleus RNA sequencing with genetic lineage tracing to reveal the existence of a distinct subpopulation of Ucp1-&Cidea+ adipocytes that arises from brown-to-white conversion during postnatal life in the periureter region of mouse PRAT. Cold exposure restores Ucp1 expression and a thermogenic phenotype in this subpopulation. These cells have a transcriptome that is distinct from subcutaneous beige adipocytes and may represent a unique type of cold-recruitable adipocytes. These results pave the way for studies of PRAT physiology and mechanisms controlling the plasticity of brown/white adipocyte phenotypes.
Assuntos
Adipócitos Bege , Tecido Adiposo , Camundongos , Animais , Tecido Adiposo/metabolismo , Adipócitos Brancos , Adipócitos Marrons/metabolismo , Termogênese/genética , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/fisiologiaRESUMO
IgG accumulation in white adipose tissue contributes to aging-associated metabolic dysfunction.
Assuntos
Tecido Adiposo Branco , Envelhecimento , Humanos , Tecido Adiposo Branco/metabolismo , Obesidade/metabolismo , Tecido Adiposo/metabolismoRESUMO
BACKGROUND: A better understanding of adipose tissue (AT) dysfunction, which includes morphological and functional changes such as adipocyte hypertrophy as well as impaired adipogenesis, lipid storage/mobilization, endocrine and inflammatory responses, is needed in the context of obesity. One dimension of AT dysfunction, secretory adiposopathy, often assessed as a low plasma adiponectin (A)/leptin (L) ratio, is commonly observed in obesity. The aim of this study was to examine markers of AT development and metabolism in 67 women of varying age and adiposity (age: 40-62 years; body mass index, BMI: 17-41 kg/m2) according to levels of adiponectinemia, leptinemia or the plasma A/L ratio. METHODS: Body composition, regional AT distribution and circulating adipokines were determined. Lipolysis was measured from glycerol release in subcutaneous abdominal (SCABD) and omental (OME) adipocytes under basal, isoproterenol-, forskolin (FSK)- and dibutyryl-cyclic AMP (DcAMP)-stimulated conditions. Adipogenesis (C/EBP-α/ß/δ, PPAR-γ2 and SREBP-1c) and lipid metabolism (ß2-ARs, HSL, FABP4, LPL and GLUT4) gene expression (RT-qPCR) was assessed in both fat depots. Participants in the upper versus lower tertile of adiponectin, leptin or the A/L ratio were compared. RESULTS: Basal lipolysis was similar between groups. Women with a low plasma A/L ratio were characterized by higher adiposity and larger SCABD and OME adipocytes (p<0.01) compared to those with a high ratio. In OME adipocytes, women in the low adiponectinemia tertile showed higher isoproterenol-stimulated lipolysis (0.01
Assuntos
Adiponectina , Leptina , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Adiponectina/metabolismo , Leptina/metabolismo , Isoproterenol/metabolismo , Tecido Adiposo/metabolismo , Obesidade/metabolismoRESUMO
BACKGROUND: Congenital generalized lipodystrophy (CGL) is a rare inherited disease characterized by a near-total absence of adipose tissue and is associated with organ system abnormalities and severe metabolic complications. Here, we have analyzed the disease characteristics of the largest CGL cohort from the Middle East and North Africa (MENA) who have not received lipodystrophy-specific treatment. METHODS: CGL was diagnosed clinically by treating physicians through physical assessment and supported by genetic analysis, fat loss patterns, family history, and the presence of parental consanguinity. Data were obtained at the time of patient diagnosis and during leptin-replacement naïve follow-up visits as permitted by available medical records. RESULTS: Data from 43 patients with CGL (37 females, 86%) were collected from centers located in eight countries. The mean (median, range) age at diagnosis was 5.1 (1.0, at birth-37) years. Genetic analysis of the overall cohort showed that CGL1 (n = 14, 33%) and CGL2 (n = 18, 42%) were the predominant CGL subtypes followed by CGL4 (n = 10, 23%); a genetic diagnosis was unavailable for one patient (2%). There was a high prevalence of parental consanguinity (93%) and family history (67%) of lipodystrophy, with 64% (n = 25/39) and 51% (n = 20/39) of patients presenting with acromegaloid features and acanthosis nigricans, respectively. Eighty-one percent (n = 35/43) of patients had at least one organ abnormality; the most frequently affected organs were the liver (70%, n = 30/43), the cardiovascular system (37%, n = 16/43) and the spleen (33%, n = 14/43). Thirteen out of 28 (46%) patients had HbA1c > 5.7% and 20/33 (61%) had triglyceride levels > 2.26 mmol/L (200 mg/dl). Generally, patients diagnosed in adolescence or later had a greater severity of metabolic disease versus those diagnosed during childhood; however, metabolic and organ system abnormalities were observed in a subset of patients diagnosed before or at 1 year of age. CONCLUSIONS: This analysis suggests that in addition to the early onset of fat loss, family history and high consanguinity enable the identification of young patients with CGL in the MENA region. In patients with CGL who have not received lipodystrophy-specific treatment, severe metabolic disease and organ abnormalities can develop by late childhood and worsen with age.
Assuntos
Lipodistrofia Generalizada Congênita , Lipodistrofia , Feminino , Adolescente , Recém-Nascido , Humanos , Criança , Lipodistrofia Generalizada Congênita/epidemiologia , Lipodistrofia Generalizada Congênita/genética , Lipodistrofia Generalizada Congênita/complicações , Lipodistrofia/epidemiologia , Lipodistrofia/genética , Tecido Adiposo , África do Norte/epidemiologia , Oriente Médio/epidemiologiaRESUMO
Adipose tissue is an abundant and accessible source of stem cells with multipotent properties suitable for tissue engineering and regenerative medical applications. Adipose-derived stromal/stem cells (ASCs) have been widely used in tissue engineering and cell therapy. In addition, the clinical application of ASCs in the treatment of inflammation and injury has been proven a success. Here, we describe methods from our own laboratory and the literature for the isolation and expansion of Adipose-derived stromal/stem cells (ASCs). We present a large-scale procedure suitable for processing >100 mL volumes of lipoaspirate tissue specimens by collagenase digestion, a related procedure suitable for processing adipose tissue aspirates without digestion, and a procedure suitable for intact human adipose tissue, such as buccal fat pads in the maxillofacial region.
Assuntos
Adipócitos , Tecido Adiposo , Humanos , Células Estromais , Células-Tronco , Engenharia Tecidual/métodos , Diferenciação Celular , Células CultivadasRESUMO
Perivascular cells represent an in vivo counterpart of mesenchymal stromal/stem cells that populate the outer layer of blood vessels. Pericytes in capillaries and microvessels and adventitial cells of large arteries and veins give rise to stem/progenitor cells when isolated and cultured in vitro. These cells have been considered candidate cell types for cell therapy. Adipose tissue, being highly vascularized, dispensable, and easily accessed, is a viable option to obtain perivascular cells for use in research and in clinical trials. Here, we describe our established protocol to extract perivascular cells from human fat through fluorescence-activated cell sorting, which allows for the isolation of defined populations of progenitor cells with high reproducibility.
Assuntos
Células-Tronco Mesenquimais , Humanos , Citometria de Fluxo , Reprodutibilidade dos Testes , Células-Tronco Mesenquimais/metabolismo , Pericitos/metabolismo , Tecido Adiposo , Diferenciação CelularRESUMO
Human adipose-derived stromal/stem cells (hASCs) are a promising source of adult stem cells used in numerous applications in regenerative medicine. We present the protocols from our laboratory for isolating and expanding hASCs. The isolation of hASCs involves the enzymatic digestion of adipose tissue and subsequent culturing of the isolated cells.
Assuntos
Células-Tronco Mesenquimais , Adulto , Humanos , Adipócitos , Tecido Adiposo , Células Estromais , Medicina Regenerativa , Diferenciação CelularRESUMO
Murine models of obesity or reduced adiposity are a valuable resource for understanding the role of adipocyte dysfunction in metabolic disorders. Adipose tissue stromal vascular cells or primary adipocytes derived from murine adipose tissue and grown in culture are essential tools for studying the mechanisms underlying adipocyte development and function. Herein, we describe methods for the isolation, expansion, and long-term storage of murine adipose-derived stromal/stem cells, along with protocols for inducing adipogenesis to white or beige adipocytes in this cell population and osteogenic differentiation. Isolation of the adipose stromal vascular fraction cells for flow cytometric analysis is also described.
Assuntos
Adipogenia , Adiposidade , Camundongos , Humanos , Animais , Citometria de Fluxo/métodos , Osteogênese , Adipócitos , Tecido Adiposo , Diferenciação Celular , Obesidade/metabolismo , Células-TroncoRESUMO
Autologous fat transplantation has revolutionized soft tissue reconstruction, but conventional methods remain unpredictable as graft resorption rates are high due to lack of vascularization. The advent of adipose-derived stem cells (ASCs) has led to improvement of fat grafting outcomes, in part to their ability to undergo facile differentiation into adipose tissue, their angiogenic properties, and their ability to express and secrete multiple growth factors. This chapter discusses the isolation and characterization of human ASCs, its expansion in vitro, and relevant in vivo models for adipose tissue engineering.
Assuntos
Tecido Adiposo , Transplante de Células-Tronco Mesenquimais , Humanos , Adipócitos , Diferenciação Celular , Neovascularização Fisiológica , Engenharia TecidualRESUMO
Cats are among the most popular household pets. However, compared to other species, there is little information specific to feline adult mesenchymal stromal/stem cells. Despite the phylogenetic distance between domesticated cats, Felis silvestris catus, and humans, they share some similar health challenges like kidney disease, asthma, and diabetes. Investigative efforts have been focused on adult adipose-derived stromal/stem cell (ASC) therapies to address feline illnesses, including de novo pancreatic tissue generation for diabetes treatment. Given the relatively small size of domestic cats, optimized cell isolation from small quantities of adipose tissue is important in the development of feline ASC-based therapies. Additionally, there are unique features of feline ASC culture conditions and characterization. This chapter contains a few of the novel aspects of feline ASC isolation, culture, preservation, and differentiation.
Assuntos
Tecido Adiposo , Diabetes Mellitus , Humanos , Adulto , Gatos , Animais , Filogenia , Diferenciação Celular , Separação Celular/veterináriaRESUMO
Adipose tissue provides a valuable cell source for tissue engineering, regenerative medicine, and adipose tissue biology studies. The most widely used adipose-derived stromal/stem cells (ASCs) isolation protocol involves enzymatic digestion with collagenase. However, the yield of the method often proves to be poor if not impossible for collection of sufficient stromal vascular fraction (SVF) for expansion when the sample size is small, for instance when only newborn mice are available for cell culture. Here, we describe an efficient protocol for the isolation and expansion of ASCs using explant culture as an alternative. Briefly, adipose tissue was minced after removing excess liquid. Then, the minced tissue was placed in culture dishes or flasks. The cells will migrate out of tissue and adhere to the culture surface after one or more days.
Assuntos
Adipócitos , Tecido Adiposo , Camundongos , Animais , Células Estromais , Engenharia Tecidual/métodos , Obesidade , Células-Tronco , Diferenciação CelularRESUMO
Adult mesenchymal stromal/stem cells (MSCs) are a standard component of de novo tissue generation to treat and study injury, disease, and degeneration. Canine patients constitute a major component of veterinary practice, and dogs share numerous pathologic conditions with humans. The relative abundance of adipose-derived stromal/stem cells (ASCs) in various canine adipose tissue depots is well described. Refined isolation, characterization, and differentiation techniques contribute to the collective knowledge of ASC phenotypes and subpopulations for specific tissue targets. Continued efforts to advance the knowledge of canine ASC behavior in vivo are critical to harnessing the full potential of primary cell isolates. This chapter contains a description of techniques to isolate, characterize, and differentiate canine ASCs.
Assuntos
Tecido Adiposo , Células-Tronco Multipotentes , Humanos , Adulto , Cães , Animais , Diferenciação Celular , Adipócitos , Separação Celular/métodosRESUMO
Adipose-derived stromal/stem cells (ASCs) and decellularized adipose tissue (DAT) are adipose tissue products obtained from individuals undergoing fat removal procedures like liposuction, lipectomy, or breast reduction. DAT hydrogel is prepared by removing the cells from the adipose tissue and digesting it to form a liquid material that forms a gel at physiological temperature. ASCs seeded on DAT have displayed osteogenic potential in vitro and in animal models of bone defects. Herein, we describe the methods for preparing DAT hydrogel, ASC seeding in DAT hydrogel, osteogenic differentiation of ASCs, creation of critical-sized femur defect model in mice, its treatment with ASC-DAT hydrogel, and analyses.
Assuntos
Hidrogéis , Osteogênese , Animais , Camundongos , Osteogênese/fisiologia , Tecido Adiposo , Adipócitos , Diferenciação Celular/fisiologia , Células-TroncoRESUMO
Advances in technology and automation over the past several decades have made it feasible to perform high-throughput compound screening with cell spheroids, a valuable approach for drug discovery. It is entirely feasible to generate multiple 384-well plates containing adipose spheroids from cryopreserved, single-donor, adipose stem cells, thus incorporating genetic diversity into the discovery stages of research. In this protocol, we describe our method for isolating primary human adipose stem cells and synthesizing cell spheroids comprised of mature adipocytes and stromal cells. Also included are representative outcome measurements useful for characterizing adipocyte metabolism and health. Wherever possible, we describe technologies that can be used to automate characterization and increase throughput.
Assuntos
Adipócitos , Tecido Adiposo , Humanos , Tecido Adiposo/metabolismo , Adipócitos/metabolismo , Esferoides Celulares , Células Estromais , Obesidade/metabolismo , Células-Tronco/metabolismo , Diferenciação CelularRESUMO
Compared to two-dimensional monolayer culture, cells cultured in three-dimensional (3D) platforms provide a more biochemically and physiologically relevant environment to study cell-cell and cell-extracellular matrix interactions in vitro. Using the liquid overlay technique, a scaffold-free method to generate 3D spheroids from human adipose-derived stem cells is described.