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Adipose Tissue Development Relies on Coordinated Extracellular Matrix Remodeling, Angiogenesis, and Adipogenesis. Biomedicines 2022; 10:biomedicines10092227. [PMID: 36140327 PMCID: PMC9496222 DOI: 10.3390/biomedicines10092227] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/31/2022] [Accepted: 09/02/2022] [Indexed: 11/24/2022] Open
Abstract
Despite developing prenatally, the adipose tissue is unique in its ability to undergo drastic growth even after reaching its mature size. This development and subsequent maintenance rely on the proper coordination between the vascular niche and the adipose compartment. In this review, the process of adipose tissue development is broken down to explain (1) the ultrastructural matrix remodeling that is undertaken during simultaneous adipogenesis and angiogenesis, (2) the paracrine crosstalk involved during adipose development, (3) the mechanical regulators involved in adipose growth, and (4) the proteolytic and paracrine oversight for matrix remodeling during adipose development. It is crucial to gain a better understanding of the complex relationships that exist between adipose tissue and the vasculature during tissue development to provide insights into the pathological tissue expansion of obesity and to develop improved soft-tissue reconstruction techniques.
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Lecoutre S, Lambert M, Drygalski K, Dugail I, Maqdasy S, Hautefeuille M, Clément K. Importance of the Microenvironment and Mechanosensing in Adipose Tissue Biology. Cells 2022; 11:cells11152310. [PMID: 35954152 PMCID: PMC9367348 DOI: 10.3390/cells11152310] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/19/2022] [Accepted: 07/23/2022] [Indexed: 11/16/2022] Open
Abstract
The expansion of adipose tissue is an adaptive mechanism that increases nutrient buffering capacity in response to an overall positive energy balance. Over the course of expansion, the adipose microenvironment undergoes continual remodeling to maintain its structural and functional integrity. However, in the long run, adipose tissue remodeling, typically characterized by adipocyte hypertrophy, immune cells infiltration, fibrosis and changes in vascular architecture, generates mechanical stress on adipose cells. This mechanical stimulus is then transduced into a biochemical signal that alters adipose function through mechanotransduction. In this review, we describe the physical changes occurring during adipose tissue remodeling, and how they regulate adipose cell physiology and promote obesity-associated dysfunction in adipose tissue.
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Affiliation(s)
- Simon Lecoutre
- Nutrition and Obesities: Systemic Approaches Research Group (Nutri-Omics), Sorbonne Université, INSERM, F-75013 Paris, France; (S.L.); (K.D.); (I.D.)
| | - Mélanie Lambert
- Labex Inflamex, Université Sorbonne Paris Nord, INSERM, F-93000 Bobigny, France;
| | - Krzysztof Drygalski
- Nutrition and Obesities: Systemic Approaches Research Group (Nutri-Omics), Sorbonne Université, INSERM, F-75013 Paris, France; (S.L.); (K.D.); (I.D.)
| | - Isabelle Dugail
- Nutrition and Obesities: Systemic Approaches Research Group (Nutri-Omics), Sorbonne Université, INSERM, F-75013 Paris, France; (S.L.); (K.D.); (I.D.)
| | - Salwan Maqdasy
- Department of Medicine (H7), Karolinska Institutet Hospital, C2-94, 14186 Stockholm, Sweden;
| | - Mathieu Hautefeuille
- Laboratoire de Biologie du Développement (UMR 7622), IBPS, Sorbonne Université, F-75005 Paris, France;
| | - Karine Clément
- Nutrition and Obesities: Systemic Approaches Research Group (Nutri-Omics), Sorbonne Université, INSERM, F-75013 Paris, France; (S.L.); (K.D.); (I.D.)
- Assistance Publique Hôpitaux de Paris, Nutrition Department, CRNH Ile-de-France, Pitié-Salpêtrière Hospital, F-75013 Paris, France
- Correspondence: or
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Rendon CJ, Flood E, Thompson JM, Chirivi M, Watts SW, Contreras GA. PIEZO1 mechanoreceptor activation reduces adipogenesis in perivascular adipose tissue preadipocytes. Front Endocrinol (Lausanne) 2022; 13:995499. [PMID: 36120469 PMCID: PMC9471253 DOI: 10.3389/fendo.2022.995499] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
During hypertension, vascular remodeling allows the blood vessel to withstand mechanical forces induced by high blood pressure (BP). This process is well characterized in the media and intima layers of the vessel but not in the perivascular adipose tissue (PVAT). In PVAT, there is evidence for fibrosis development during hypertension; however, PVAT remodeling is poorly understood. In non-PVAT depots, mechanical forces can affect adipogenesis and lipogenic stages in preadipocytes. In tissues exposed to high magnitudes of pressure like bone, the activation of the mechanosensor PIEZO1 induces differentiation of progenitor cells towards osteogenic lineages. PVAT's anatomical location continuously exposes it to forces generated by blood flow that could affect adipogenesis in normotensive and hypertensive states. In this study, we hypothesize that activation of PIEZO1 reduces adipogenesis in PVAT preadipocytes. The hypothesis was tested using pharmacological and mechanical activation of PIEZO1. Thoracic aorta PVAT (APVAT) was collected from 10-wk old male SD rats (n=15) to harvest preadipocytes that were differentiated to adipocytes in the presence of the PIEZO1 agonist Yoda1 (10 µM). Mechanical stretch was applied with the FlexCell System at 12% elongation, half-sine at 1 Hz simultaneously during the 4 d of adipogenesis (MS+, mechanical force applied; MS-, no mechanical force used). Yoda1 reduced adipogenesis by 33% compared with CON and, as expected, increased cytoplasmic Ca2+ flux. MS+ reduced adipogenesis efficiency compared with MS-. When Piezo1 expression was blocked with siRNA [siPiezo1; NC=non-coding siRNA], the anti-adipogenic effect of Yoda1 was reversed in siPiezo1 cells but not in NC; in contrast, siPiezo1 did not alter the inhibitory effect of MS+ on adipogenesis. These data demonstrate that PIEZO1 activation in PVAT reduces adipogenesis and lipogenesis and provides initial evidence for an adaptive response to excessive mechanical forces in PVAT during hypertension.
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Affiliation(s)
- C. Javier Rendon
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, MI, United States
- *Correspondence: C. Javier Rendon,
| | - Emma Flood
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - Janice M. Thompson
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - Miguel Chirivi
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, MI, United States
| | - Stephanie W. Watts
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - G. Andres Contreras
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, MI, United States
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Sonenblum SE, Measel M, Sprigle SH, Greenhalgh J, Cathcart JM. An Exploratory Analysis of the Role of Adipose Characteristics in Fulltime Wheelchair Users' Pressure Injury History. Front Bioeng Biotechnol 2021; 9:753897. [PMID: 34912788 PMCID: PMC8666593 DOI: 10.3389/fbioe.2021.753897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 10/26/2021] [Indexed: 11/13/2022] Open
Abstract
Aim: The goals of this study were 1) to identify the relationship between adipose (subcutaneous and intramuscular) characteristics and pressure injury (PrI) history in wheelchair users and 2) to identify subject characteristics, including biomechanical risk, that are related to adipose characteristics. Materials and Methods: The buttocks of 43 full-time wheelchair users with and without a history of pelvic PrIs were scanned in a seated posture in a FONAR UPRIGHT® MRI. Intramuscular adipose (the relative difference in intensity between adipose and gluteus maximus) and the subcutaneous adipose characteristics (the relative difference in intensity between subcutaneous adipose under and surrounding the ischium) were compared to PrI history and subject characteristics. Results: Participants with a history of PrIs had different subcutaneous fat (subQF) characteristics than participants without a history of PrIs. Specifically, they had significantly darker adipose under the ischium than surrounding the ischium (subQF effect size = 0.21) than participants without a history of PrIs (subQF effect size = 0.58). On the other hand, only when individuals with complete fat infiltration (n = 7) were excluded did individuals with PrI history have more fat infiltration than those without a PrI history. The presence of spasms (μ intramuscular adipose, 95% CI with spasms 0.642 [0.430, 0.855], without spasms 0.168 [-0.116, 0.452], p = 0.01) and fewer years using a wheelchair were associated with leaner muscle (Pearson Corr = -0.442, p = 0.003). Conclusion: The results of the study suggest the hypothesis that changes in adipose tissue under the ischial tuberosity (presenting as darker SubQF) are associated with increased biomechanical risk for pressure injury. Further investigation of this hypothesis, and the role of intramuscular fat infiltration in PrI development, may help our understanding of PrI etiology. It may also lead to clinically useful diagnostic techniques that can identify changes in adipose and biomechanical risk to inform early preventative interventions.
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Affiliation(s)
- Sharon Eve Sonenblum
- Rehabilitation Engineering and Applied Research Laboratory, The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Megan Measel
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Stephen H Sprigle
- Rehabilitation Engineering and Applied Research Laboratory, The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, United States.,College of Design, Georgia Institute of Technology, Atlanta, GA, United States
| | | | - John McKay Cathcart
- School of Health Sciences, Ulster University, Northern Ireland, Coleraine, United Kingdom
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Chen X, Lu F, Yuan Y. The Application and Mechanism of Action of External Volume Expansion in Soft Tissue Regeneration. TISSUE ENGINEERING PART B-REVIEWS 2021; 27:181-197. [PMID: 32821009 DOI: 10.1089/ten.teb.2020.0137] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Xihang Chen
- Department of Plastic and Cosmetic Surgery, Southern Medical University, Nanfang Hospital, Guangzhou, China
| | - Feng Lu
- Department of Plastic and Cosmetic Surgery, Southern Medical University, Nanfang Hospital, Guangzhou, China
| | - Yi Yuan
- Department of Plastic and Cosmetic Surgery, Southern Medical University, Nanfang Hospital, Guangzhou, China
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Contreras GA, Yang Y, Flood ED, Garver H, Bhattacharya S, Fink GD, Watts SW. Blood pressure changes PVAT function and transcriptome: use of the mid-thoracic aorta coarcted rat. Am J Physiol Heart Circ Physiol 2020; 319:H1313-H1324. [PMID: 33006918 DOI: 10.1152/ajpheart.00332.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Perivascular adipose tissue (PVAT) modifies the contractile function of the vessel it surrounds (outside-in signaling). Little work points to the vessel actively affecting its surrounding PVAT. We hypothesized that inside-out arterial signaling to PVAT would be evidenced by the response of PVAT to changes in tangential vascular wall stress. Rats coarcted in the mid-thoracic aorta created PVAT tissues that would exemplify pressure-dependent changes (above vs. below coarctation); a sham rat was used as a control. Radiotelemetry revealed a ∼20 mmHg systolic pressure gradient across the coarctation 4 wk after surgery. Four measures (histochemical, adipocyte progenitor proliferation and differentiation, isometric tone, and bulk mRNA sequencing) were used to compare PVAT above versus below the ligature in sham and coarcted rats. Neither aortic collagen deposition in PVAT nor arterial media/radius ratio above coarctation was increased versus below segments. However, differentiated adipocytes derived from PVAT above the coarctation accumulated substantially less triglycerides versus those below; their relative proliferation rate as adipogenic precursors was not different. Functionally, the ability of PVAT to assist stress relaxation of isolated aorta was reduced in rings above versus below the coarctation. Transcriptomic analyses revealed that the coarctation resulted in more differentially expressed genes (DEGs) between PVAT above versus below when compared with sham samples from the same locations. A majority of DEGs were in PVAT below the coarctation and were enriched in neuronal/synaptic terms. These findings provide initial evidence that signaling from the vascular wall, as stimulated by a pressure change, influences the function and transcriptional profile of its PVAT.NEW & NOTEWORTHY A mid-thoracic aorta coarcted rat was created to generate a stable pressure difference above versus below the coarctation ligature. This study determined that the PVAT around the thoracic aorta exposed to a higher pressure has a significantly reduced ability to assist stress relaxation versus that below the ligature and appears to retain the ability to be anticontractile. At the same time, the PVAT around the thoracic aorta exposed to higher pressure had a reduced adipogenic potential versus that below the ligature. Transcriptomics analyses indicated that PVAT below the coarctation showed the greatest number of DEGs with an increased profile of the synaptic neurotransmitter gene network.
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Affiliation(s)
- G Andres Contreras
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, Michigan
| | - Yongliang Yang
- Department of Biomedical Engineering, Michigan State University, East Lansing, Michigan.,Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan
| | - Emma D Flood
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Hannah Garver
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Sudin Bhattacharya
- Department of Biomedical Engineering, Michigan State University, East Lansing, Michigan.,Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan.,Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan.,Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan
| | - Gregory D Fink
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Stephanie W Watts
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
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Katzengold R, Orlov A, Gefen A. A novel system for dynamic stretching of cell cultures reveals the mechanobiology for delivering better negative pressure wound therapy. Biomech Model Mechanobiol 2020; 20:193-204. [PMID: 32803464 DOI: 10.1007/s10237-020-01377-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 08/05/2020] [Indexed: 12/20/2022]
Abstract
Serious wounds, both chronic and acute (e.g., surgical), are among the most common, expensive and difficult-to-treat health problems. Negative pressure wound therapy (NPWT) is considered a mainstream procedure for treating both wound types. Soft tissue deformation stimuli are the crux of NPWT, enhancing cell proliferation and migration from peri-wound tissues which contributes to healing. We developed a dynamic stretching device (DSD) contained in a miniature incubator for applying controlled deformations to fibroblast wound assays. Prior to the stretching experiments, fibroblasts were seeded in 6-well culture plates with elastic substrata and let to reach confluency. Squashing damage was then induced at the culture centers, and the DSD was activated to deliver stretching regimes that represented common clinical NPWT protocols at two peak strain levels, 0.5% and 3%. Analyses of the normalized maximal migration rate (MMR) data for the collective cell movement revealed that for the 3% strain level, the normalized MMR of cultures subjected to a 0.1 Hz stretch frequency regime was ~ 1.4 times and statistically significantly greater (p < 0.05) than that of the cultures subjected to no-stretch (control) or to static stretch (2nd control). Correspondingly, analysis of the time to gap closure data indicated that the closure time of the wound assays subjected to the 0.1 Hz regime was ~ 30% shorter than that of the cultures subjected to the control regimes (p < 0.05). Other simulated NPWT protocols did not emerge as superior to the controls. The present method and system are a powerful platform for further revealing the mechanobiology of NPWT and for improving this technology.
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Affiliation(s)
- Rona Katzengold
- The Herbert J. Berman Chair in Vascular Bioengineering, Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, 6997801, Tel Aviv, Israel
| | - Alexey Orlov
- The Herbert J. Berman Chair in Vascular Bioengineering, Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, 6997801, Tel Aviv, Israel
| | - Amit Gefen
- The Herbert J. Berman Chair in Vascular Bioengineering, Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, 6997801, Tel Aviv, Israel.
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Lustig M, Zadka Y, Levitsky I, Gefen A, Benayahu D. Adipocytes Migration is Altered Through Differentiation. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2019; 25:1195-1200. [PMID: 31358078 DOI: 10.1017/s1431927619014727] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Adipogenesis is a developmental process in which an elongated preadipocyte differentiates to a round adipocyte along with the accumulation of lipid droplets. In the present study, we focus on the study of cell motility at the single-cell level, toward expanding our knowledge regarding the cytoskeleton alteration during differentiation; since-cell motility is mediated by cytoskeletal components. We used the holographic-microscopy live imaging technique to evaluate, for the first time in the literature, differences between the motility of nondifferentiated preadipocytes and differentiated mature adipocytes in living cell cultures over time. We revealed that mean motility speed of preadipocytes was significantly higher (fourfold) than that of adipocytes, and that the movement of preadipocytes is less consistent and more extensive. Furthermore, we found that preadipocytes tend to migrate to farther distances, while mature adipocytes remain relatively close to their original location. The results presented here are in agreement with the fact that the cytoskeleton of adipocytes is altered during differentiation and similarly, points to the fact that the cell-sensing mechanisms are changing during differentiation. Our research paves the way to gain better insights of the differentiation process and its implications on larger scale systems in the context of obesity.
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Affiliation(s)
- Maayan Lustig
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Yuliya Zadka
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Irena Levitsky
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Amit Gefen
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Dafna Benayahu
- Department of Cell and Developmental Biology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Bodle J, Hamouda MS, Cai S, Williams RB, Bernacki SH, Loboa EG. Primary Cilia Exhibit Mechanosensitivity to Cyclic Tensile Strain and Lineage-Dependent Expression in Adipose-Derived Stem Cells. Sci Rep 2019; 9:8009. [PMID: 31142808 PMCID: PMC6541635 DOI: 10.1038/s41598-019-43351-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 04/23/2019] [Indexed: 02/06/2023] Open
Abstract
Non-motile primary cilia are dynamic cellular sensory structures and are expressed in adipose-derived stem cells (ASCs). We have previously shown that primary cilia are involved in chemically-induced osteogenic differentiation of human ASC (hASCs) in vitro. Further, we have reported that 10% cyclic tensile strain (1 Hz, 4 hours/day) enhances hASC osteogenesis. We hypothesize that primary cilia respond to cyclic tensile strain in a lineage dependent manner and that their mechanosensitivity may regulate the dynamics of signaling pathways localized to the cilium. We found that hASC morphology, cilia length and cilia conformation varied in response to culture in complete growth, osteogenic differentiation, or adipogenic differentiation medium, with the longest cilia expressed in adipogenically differentiating cells. Further, we show that cyclic tensile strain both enhances osteogenic differentiation of hASCs while it suppresses adipogenic differentiation as evidenced by upregulation of RUNX2 gene expression and downregulation of PPARG and IGF-1, respectively. This study demonstrates that hASC primary cilia exhibit mechanosensitivity to cyclic tensile strain and lineage-dependent expression, which may in part regulate signaling pathways localized to the primary cilium during the differentiation process. We highlight the importance of the primary cilium structure in mechanosensing and lineage specification and surmise that this structure may be a novel target in manipulating hASC for in tissue engineering applications.
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Affiliation(s)
- Josephine Bodle
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, North Carolina, 27695, USA.
| | - Mehdi S Hamouda
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, North Carolina, 27695, USA
| | - Shaobo Cai
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina, 27695, USA
| | - Ramey B Williams
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, North Carolina, 27695, USA
| | - Susan H Bernacki
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, North Carolina, 27695, USA
| | - Elizabeth G Loboa
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, North Carolina, 27695, USA.
- College of Engineering at University of Missouri, W1051 Thomas & Nell Lafferre Hall, Columbia, MO, 65211, USA.
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Zhang Y, Yu M, Zhao X, Dai M, Chen C, Tian W. Optimizing adipose tissue extract isolation with stirred suspension culture. Connect Tissue Res 2019; 60:178-188. [PMID: 29852798 DOI: 10.1080/03008207.2018.1483357] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVES Adherent culture which is used to collect adipose tissue extract (ATE) previously brings the problem of inhomogeneity and non-repeatability. Here we aim to extract ATE with stirred suspension culture to speed up the extraction process, stabilize the yield, and improve consistent potency metrics of ATE. MATERIALS AND METHODS ATE was collected with adherent culture (ATE-A) and stirred suspension culture (ATE-S) separately. Protein yield and composition were detected by SDS-PAGE, while cytokines in ATE were determined with ELISA. The adipogenic and angiogenic potential of ATE were compared by western blot and qPCR. In addition, haematoxylin and eosin staining and lactate dehydrogenase (LDH) activity assays were used to analyze the cell viability of adipose tissue cultured with different methods. RESULTS The yield of ATE-S was consistent while ATE-A varied notably. Characterization of the protein composition and exosome-like vesicles (ELVs) indicated no significant difference between ATE-S and ATE-A. The concentrations of cytokines (VEGF, bFGF, and IL-6) showed no significant difference, while IGF in ATE-S was higher than that in ATE-A. ATE-S showed upregulated adipogenic and angiogenic potential compared to ATE-A. Morever, stirred suspension culture decreased the LDH activity of ATE while increased the number of viable adipocytes and reduced adipose tissue necrosis. CONCLUSION Compared with adherent culture, stirred suspension culture is a reliable, time- and labor-saving method to collect ATE, which might be used to improve the downstream applications of ATE.
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Affiliation(s)
- Yan Zhang
- a State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Oral Regenerative Medicine & Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology , Sichuan University , Chengdu , China
| | - Mei Yu
- a State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Oral Regenerative Medicine & Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology , Sichuan University , Chengdu , China
| | - Xueyong Zhao
- a State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Oral Regenerative Medicine & Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology , Sichuan University , Chengdu , China
| | - Minjia Dai
- a State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Oral Regenerative Medicine & Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology , Sichuan University , Chengdu , China
| | - Chang Chen
- a State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Oral Regenerative Medicine & Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology , Sichuan University , Chengdu , China
| | - Weidong Tian
- a State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Oral Regenerative Medicine & Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology , Sichuan University , Chengdu , China
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11
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Lustig M, Feng Q, Payan Y, Gefen A, Benayahu D. Noninvasive Continuous Monitoring of Adipocyte Differentiation: From Macro to Micro Scales. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2019; 25:119-128. [PMID: 30712528 DOI: 10.1017/s1431927618015520] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
3T3-L1 cells serve as model systems for studying adipogenesis and research of adipose tissue-related diseases, e.g. obesity and diabetes. Here, we present two novel and complementary nondestructive methods for adipogenesis analysis of living cells which facilitate continuous monitoring of the same culture over extended periods of time, and are applied in parallel at the macro- and micro-scales. At the macro-scale, we developed visual differences mapping (VDM), a novel method which allows to determine level of adipogenesis (LOA)-a numerical index which quantitatively describes the extent of differentiation in the whole culture, and percentage area populated by adipocytes (PAPBA) across a whole culture, based on the apparent morphological differences between preadipocytes and adipocytes. At the micro-scale, we developed an improved version of our previously published image-processing algorithm, which now provides data regarding single-cell morphology and lipid contents. Both methods were applied here synergistically for measuring differentiation levels in cultures over multiple weeks. VDM revealed that the mean LOA value reached 1.11 ± 0.06 and the mean PAPBA value reached >60%. Micro-scale analysis revealed that during differentiation, the cells transformed from a fibroblast-like shape to a circular shape with a build-up of lipid droplets. We predict a vast potential for implementation of these methods in adipose-related pharmacological research, such as in metabolic-syndrome studies.
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Affiliation(s)
- Maayan Lustig
- Department of Biomedical Engineering, Faculty of Engineering,Tel Aviv University,Tel Aviv 6997801,Israel
| | - Qingling Feng
- Key Laboratory of Advanced Materials of Ministry of Education of China,School of Materials Science and Engineering, Tsinghua University,Beijing 100084,China
| | - Yohan Payan
- CNRS, Grenoble INP, TIMC-IMAG, University of Grenoble Alpes,Grenoble F-38000,France
| | - Amit Gefen
- Department of Biomedical Engineering, Faculty of Engineering,Tel Aviv University,Tel Aviv 6997801,Israel
| | - Dafna Benayahu
- Department of Cell and Developmental Biology,Sackler School of Medicine, Tel Aviv University,Tel Aviv 6997801,Israel
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Delivery of External Volume Expansion through Microdeformational Interfaces Safely Induces Angiogenesis in a Murine Model of Intact Diabetic Skin with Endothelial Cell Dysfunction. Plast Reconstr Surg 2019; 143:453-464. [DOI: 10.1097/prs.0000000000005267] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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13
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Benayahu D, Wiesenfeld Y, Sapir-Koren R. How is mechanobiology involved in mesenchymal stem cell differentiation toward the osteoblastic or adipogenic fate? J Cell Physiol 2019; 234:12133-12141. [PMID: 30633367 DOI: 10.1002/jcp.28099] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 12/07/2018] [Indexed: 12/28/2022]
Abstract
Mechanobiology plays a major role in transducing physical cues from the dynamic cellular environment into biochemical modifications that promote cell-specific differentiation paths. Mesenchymal stem cells in the bone marrow or in other mesenchymal tissues will differentiate according to the expression of transcription factors (TFs) that govern their lineage commitment. The favoring of either osteogenic or adipogenic differentiation relies on TF expression as well as mechanical properties of the cells' niche that are translated into the activation of certain signaling pathways. Physical factors can induce significant shifts in bipotential lineage commitment between osteogenesis and adipogenesis. The stiffness of the extracellular matrix (ECM) surrounding a cell, varying greatly from rigid environments close to the bone surface to softer regions in the bone marrow, can influence the path of differentiation. Additionally, mechanical loading through exercise appears to favor osteogenesis whereas disuse conditions seem to promote adipogenesis.
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Affiliation(s)
- Dafna Benayahu
- Department of Cell and Developmental Biology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yarden Wiesenfeld
- Department of Cell and Developmental Biology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Rony Sapir-Koren
- Department of Cell and Developmental Biology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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14
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Lustig M, Gefen A, Benayahu D. Adipogenesis and lipid production in adipocytes subjected to sustained tensile deformations and elevated glucose concentration: a living cell-scale model system of diabesity. Biomech Model Mechanobiol 2018; 17:903-913. [PMID: 29335836 DOI: 10.1007/s10237-017-1000-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 12/29/2017] [Indexed: 12/15/2022]
Abstract
Adipocyte fate commitment is characterized by morphological changes of fibroblastic pre-adipocyte cells, and specifically by accumulation of lipid droplets (LDs) as part of the adipogenesis metabolism. Formation of LDs indicates the production of triglycerides from glucose through an insulin-regulated glucose internalization process. In obesity, adipocytes typically become insulin resistant, and glucose transport into the cells is impaired, resulting in type 2 diabetes. In the present study, we monitored the adipogenesis in 3T3-L1 cultured cells exposed to high (450 mg/dL hyperglycemia) and low (100 mg/dL physiological) glucose concentrations, in a novel cell culture model system of diabesity. In addition to glucose conditions, cells were concurrently exposed to different substrate tensile strains (12% and control) based on our prior work which revealed that adipogenesis is accelerated in cultures subjected to static, chronic substrate tensile deformations. Phase-contrast images were taken throughout the adipogenesis process (3 weeks) and were analyzed by an image processing algorithm which quantitatively monitors cell differentiation and lipid accumulation (number of LDs per cell and their radius as well as cell size and shape). The results indicated that high glucose concentrations and substrate tensile strains delivered to adipocytes accelerated lipid production by 1.7- and 1.4-fold, respectively. In addition, significant changes in average cell projected area and in other morphological attributes were observed during the differentiation process. The importance of this study is in characterizing the adipogenesis parameters as potential read-outs that can predict the occurrence of insulin resistance in the development of diabesity.
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Affiliation(s)
- Maayan Lustig
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, 69978, Tel Aviv, Israel
| | - Amit Gefen
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, 69978, Tel Aviv, Israel
| | - Dafna Benayahu
- Department of Cell and Developmental Biology, Sackler School of Medicine, Tel Aviv University, 69978, Tel Aviv, Israel.
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15
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Paul NE, Denecke B, Kim BS, Dreser A, Bernhagen J, Pallua N. The effect of mechanical stress on the proliferation, adipogenic differentiation and gene expression of human adipose-derived stem cells. J Tissue Eng Regen Med 2017; 12:276-284. [DOI: 10.1002/term.2411] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 11/16/2016] [Accepted: 01/13/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Nora E. Paul
- Department of Plastic Surgery and Hand Surgery - Burn Center; Uniklinik RWTH Aachen; Aachen Germany
| | - Bernd Denecke
- Interdisciplinary Center for Clinical Research; Uniklinik RWTH Aachen; Aachen Germany
| | - Bong-Sung Kim
- Department of Plastic Surgery and Hand Surgery - Burn Center; Uniklinik RWTH Aachen; Aachen Germany
| | - Alice Dreser
- Institute of Neuropathology; Uniklinik RWTH Aachen; Aachen Germany
| | - Jürgen Bernhagen
- Department of Vascular Biology; Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig Maximilians-University (LMU) of Munich; Munich Germany
- Munich Cluster for Systems Neurology (SyNergy); Munich Germany
| | - Norbert Pallua
- Department of Plastic Surgery and Hand Surgery - Burn Center; Uniklinik RWTH Aachen; Aachen Germany
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16
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The Combination of Tissue Dissection and External Volume Expansion Generates Large Volumes of Adipose Tissue. Plast Reconstr Surg 2017; 139:888e-899e. [DOI: 10.1097/prs.0000000000003212] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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17
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Luo L, He Y, Chang Q, Xie G, Zhan W, Wang X, Zhou T, Xing M, Lu F. Polycaprolactone nanofibrous mesh reduces foreign body reaction and induces adipose flap expansion in tissue engineering chamber. Int J Nanomedicine 2016; 11:6471-6483. [PMID: 27980405 PMCID: PMC5147407 DOI: 10.2147/ijn.s114295] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Tissue engineering chamber technique can be used to generate engineered adipose tissue, showing the potential for the reconstruction of soft tissue defects. However, the consequent foreign body reaction induced by the exogenous chamber implantation causes thick capsule formation on the surface of the adipose flap following capsule contracture, which may limit the internal tissue expansion. The nanotopographical property and architecture of nanofibrous scaffold may serve as a promising method for minimizing the foreign body reaction. Accordingly, electrospinning porous polycaprolactone (PCL) nanofibrous mesh, a biocompatible synthetic polymer, was attached to the internal surface of the chamber for the reducing local foreign body reaction. Adipose flap volume, level of inflammation, collagen quantification, capsule thickness, and adipose tissue-specific gene expression in chamber after implantation were evaluated at different time points. The in vivo study revealed that the engineered adipose flaps in the PCL group had a structure similar to that in the controls and normal adipose tissue structure but with a larger flap volume. Interleukin (IL)-1β, IL-6, and transforming growth factor-β expression decreased significantly in the PCL group compared with the control. Moreover, the control group had much more collagen deposition and thicker capsule than that observed in the PCL group. These results indicate that the unique nanotopographical effect of electrospinning PCL nanofiber can reduce foreign body reaction in a tissue engineering chamber, which maybe a promising new method for generating a larger volume of mature, vascularized, and stable adipose tissue.
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Affiliation(s)
- Lin Luo
- Department of Plastic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Yunfan He
- Department of Plastic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
- Department of Mechanical Engineering, Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Qiang Chang
- Department of Plastic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
- Department of Mechanical Engineering, Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Gan Xie
- Department of Plastic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Weiqing Zhan
- Department of Plastic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Xuecen Wang
- Department of Plastic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Tao Zhou
- Department of Plastic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Malcolm Xing
- Department of Mechanical Engineering, Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba, Canada
- Children’s Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
| | - Feng Lu
- Department of Plastic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
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Choi J, Lee SY, Yoo YM, Kim CH. Maturation of Adipocytes is Suppressed by Fluid Shear Stress. Cell Biochem Biophys 2016; 75:87-94. [PMID: 27830366 DOI: 10.1007/s12013-016-0771-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 10/31/2016] [Indexed: 10/20/2022]
Abstract
Preadipocytes are mechano-responsive cells and their differentiation to adipocytes may be regulated by various types of physical stimulation. Understanding the mechanism of differentiation, which increases the number of adipocytes and lipid accumulation is important in the study of obesity-related diseases. In this study, we investigated the effects of physical stimulation at different stages of adipogenic differentiation using physiological levels of fluid shear stress. Preadipocytes were treated with dexamethasone, 3-isobutyl-1-methylxanthine and insulin for 3 days (induction period) and incubated for additional 6 days for maturation. Fluid shear stress of 1 Pa at 1 Hz was applied for 1 h at different stages of differentiation. Fluid shear stress applied at the maturation period significantly reduced the expressions of C/enhancer binding protein (EBP)α and peroxisome proliferator-activated receptor (PPAR)γ2 leading to reduced lipid accumulation. Fluid shear stress applied at the early or late stages of the induction period only decreased peroxisome proliferator-activated receptor γ2 expression without any significant changes in lipid accumulation. Stimulation at multiple days during the induction period did not result in changes in lipid accumulation compared to stimulation at a single day. These results suggest that lipid droplet accumulation is effectively decreased by fluid shear stress applied during the cell maturation period. Understanding the cellular response to physical stimulation throughout the entire adipocyte differentiation period may be important in controlling adipogenesis by physical stimulation.
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Affiliation(s)
- Jongyun Choi
- Department of Biomedical Engineering, College of Health Science, Yonsei University, Wonju, Gangwon-do, 26493, Republic of Korea
| | - Sei Young Lee
- Department of Biomedical Engineering, College of Health Science, Yonsei University, Wonju, Gangwon-do, 26493, Republic of Korea
| | - Yeong-Min Yoo
- Department of Biomedical Engineering, College of Health Science, Yonsei University, Wonju, Gangwon-do, 26493, Republic of Korea
| | - Chi Hyun Kim
- Department of Biomedical Engineering, College of Health Science, Yonsei University, Wonju, Gangwon-do, 26493, Republic of Korea.
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19
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A multiscale modeling framework for studying the mechanobiology of sarcopenic obesity. Biomech Model Mechanobiol 2016; 16:275-295. [DOI: 10.1007/s10237-016-0816-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 08/08/2016] [Indexed: 01/08/2023]
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20
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Microenvironmental Control of Adipocyte Fate and Function. Trends Cell Biol 2016; 26:745-755. [PMID: 27268909 DOI: 10.1016/j.tcb.2016.05.005] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 05/09/2016] [Accepted: 05/16/2016] [Indexed: 01/07/2023]
Abstract
The properties of tissue-specific microenvironments vary widely in the human body and demonstrably influence the structure and function of many cell types. Adipocytes are no exception, responding to cues in specialized niches to perform vital metabolic and endocrine functions. The adipose microenvironment is remodeled during tissue expansion to maintain the structural and functional integrity of the tissue and disrupted remodeling in obesity contributes to the progression of metabolic syndrome, breast cancer, and other malignancies. The increasing incidence of these obesity-related diseases and the recent focus on improved in vitro models of human tissue biology underscore growing interest in the regulatory role of adipocyte microenvironments in health and disease.
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21
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Printable low-cost, sustained and dynamic cell stretching apparatus. J Biomech 2016; 49:1336-1339. [DOI: 10.1016/j.jbiomech.2016.03.026] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 03/13/2016] [Accepted: 03/16/2016] [Indexed: 12/30/2022]
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22
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23
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Unser AM, Tian Y, Xie Y. Opportunities and challenges in three-dimensional brown adipogenesis of stem cells. Biotechnol Adv 2015; 33:962-79. [PMID: 26231586 DOI: 10.1016/j.biotechadv.2015.07.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 07/07/2015] [Accepted: 07/23/2015] [Indexed: 12/21/2022]
Abstract
The formation of brown adipose tissue (BAT) via brown adipogenesis has become a notable process due to its ability to expend energy as heat with implications in the treatment of metabolic disorders and obesity. With the advent of complexity within white adipose tissue (WAT) along with inducible brown adipocytes (also known as brite and beige), there has been a surge in deciphering adipocyte biology as well as in vivo adipogenic microenvironments. A therapeutic outcome would benefit from understanding early events in brown adipogenesis, which can be accomplished by studying cellular differentiation. Pluripotent stem cells are an efficient model for differentiation and have been directed towards both white adipogenic and brown adipogenic lineages. The stem cell microenvironment greatly contributes to terminal cell fate and as such, has been mimicked extensively by various polymers including those that can form 3D hydrogel constructs capable of biochemical and/or mechanical modifications and modulations. Using bioengineering approaches towards the creation of 3D cell culture arrangements is more beneficial than traditional 2D culture in that it better recapitulates the native tissue biochemically and biomechanically. In addition, such an approach could potentially protect the tissue formed from necrosis and allow for more efficient implantation. In this review, we highlight the promise of brown adipocytes with a focus on brown adipogenic differentiation of stem cells using bioengineering approaches, along with potential challenges and opportunities that arise when considering the energy expenditure of BAT for prospective therapeutics.
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Affiliation(s)
- Andrea M Unser
- Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road Albany, NY 12203, USA
| | - Yangzi Tian
- Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road Albany, NY 12203, USA
| | - Yubing Xie
- Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road Albany, NY 12203, USA.
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24
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Frydrych M, Román S, MacNeil S, Chen B. Biomimetic poly(glycerol sebacate)/poly(l-lactic acid) blend scaffolds for adipose tissue engineering. Acta Biomater 2015; 18:40-9. [PMID: 25769230 DOI: 10.1016/j.actbio.2015.03.004] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 02/10/2015] [Accepted: 03/04/2015] [Indexed: 01/08/2023]
Abstract
Large three-dimensional poly(glycerol sebacate) (PGS)/poly(l-lactic acid) (PLLA) scaffolds with similar bulk mechanical properties to native low and high stress adapted adipose tissue were fabricated via a freeze-drying and a subsequent curing process. PGS/PLLA scaffolds containing 73vol.% PGS were prepared using two different organic solvents, resulting in highly interconnected open-pore structures with porosities and pore sizes in the range of 91-92% and 109-141μm, respectively. Scanning electron microscopic analysis indicated that the scaffolds featured different microstructure characteristics, depending on the organic solvent in use. The PGS/PLLA scaffolds had a tensile Young's modulus of 0.030MPa, tensile strength of 0.007MPa, elongation at the maximum stress of 25% and full shape recovery capability upon release of the compressive load. In vitro degradation tests presented mass losses of 11-16% and 54-55% without and with the presence of lipase enzyme in 31days, respectively. In vitro cell tests exhibited clear evidence that the PGS/PLLA scaffolds prepared with 1,4-dioxane as the solvent are suitable for culture of adipose derived stem cells. Compared to pristine PLLA scaffolds prepared with the same procedure, these scaffolds provided favourable porous microstructures, good hydrophilic characteristics, and appropriate mechanical properties for soft tissue applications, as well as enhanced scaffold cell penetration and tissue in-growth characteristics. This work demonstrates that the PGS/PLLA scaffolds have potential for applications in adipose tissue engineering.
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Affiliation(s)
- Martin Frydrych
- Department of Materials Science and Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD, United Kingdom
| | - Sabiniano Román
- Kroto Research Institute, Department of Materials Science and Engineering, University of Sheffield, Broad Lane, Sheffield S3 7HQ, United Kingdom
| | - Sheila MacNeil
- Kroto Research Institute, Department of Materials Science and Engineering, University of Sheffield, Broad Lane, Sheffield S3 7HQ, United Kingdom
| | - Biqiong Chen
- Department of Materials Science and Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD, United Kingdom.
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25
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Abstract
Adipose tissue is a complex, multicellular organ that profoundly influences the function of nearly all other organ systems through its diverse metabolite and adipokine secretome. Adipocytes are the primary cell type of adipose tissue and play a key role in maintaining energy homeostasis. The efficiency with which adipose tissue responds to whole-body energetic demands reflects the ability of adipocytes to adapt to an altered nutrient environment, and has profound systemic implications. Deciphering adipocyte cell biology is an important component of understanding how the aberrant physiology of expanding adipose tissue contributes to the metabolic dysregulation associated with obesity.
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Affiliation(s)
- Joseph M Rutkowski
- Touchstone Diabetes Center, Department of Internal Medicine, and Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Jennifer H Stern
- Touchstone Diabetes Center, Department of Internal Medicine, and Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, and Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390 Touchstone Diabetes Center, Department of Internal Medicine, and Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
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26
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Multiscale Modeling of Tissue-Engineered Fat: Is There a Deformation-Driven Positive Feedback Loop in Adipogenesis? Tissue Eng Part A 2015; 21:1354-63. [DOI: 10.1089/ten.tea.2014.0505] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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27
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Shoham N, Girshovitz P, Katzengold R, Shaked NT, Benayahu D, Gefen A. Adipocyte stiffness increases with accumulation of lipid droplets. Biophys J 2014; 106:1421-31. [PMID: 24655518 DOI: 10.1016/j.bpj.2014.01.045] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 01/24/2014] [Accepted: 01/29/2014] [Indexed: 11/17/2022] Open
Abstract
Adipogenesis and increase in fat tissue mass are mechanosensitive processes and hence should be influenced by the mechanical properties of adipocytes. We evaluated subcellular effective stiffnesses of adipocytes using atomic force microscopy (AFM) and interferometric phase microscopy (IPM), and we verified the empirical results using finite element (FE) simulations. In the AFM studies, we found that the mean ratio of stiffnesses of the lipid droplets (LDs) over the nucleus was 0.83 ± 0.14, from which we further evaluated the ratios of LDs over cytoplasm stiffness, as being in the range of 2.5 to 8.3. These stiffness ratios, indicating that LDs are stiffer than cytoplasm, were verified by means of FE modeling, which simulated the AFM experiments, and provided good agreement between empirical and model-predicted structural behavior. In the IPM studies, we found that LDs mechanically distort their intracellular environment, which again indicated that LDs are mechanically stiffer than the surrounding cytoplasm. Combining these empirical and simulation data together, we provide in this study evidence that adipocytes stiffen with differentiation as a result of accumulation of LDs. Our results are relevant to research of adipose-related diseases, particularly overweight and obesity, from a mechanobiology and cellular mechanics perspectives.
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Affiliation(s)
- Naama Shoham
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Pinhas Girshovitz
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Rona Katzengold
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Natan T Shaked
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Dafna Benayahu
- Department of Cell and Developmental Biology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Amit Gefen
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel.
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28
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Ben-Or Frank M, Shoham N, Benayahu D, Gefen A. Effects of accumulation of lipid droplets on load transfer between and within adipocytes. Biomech Model Mechanobiol 2014; 14:15-28. [DOI: 10.1007/s10237-014-0582-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Accepted: 03/27/2014] [Indexed: 12/31/2022]
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29
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Shoham N, Sasson AL, Lin FH, Benayahu D, Haj-Ali R, Gefen A. The mechanics of hyaluronic acid/adipic acid dihydrazide hydrogel: towards developing a vessel for delivery of preadipocytes to native tissues. J Mech Behav Biomed Mater 2013; 28:320-31. [PMID: 24021174 DOI: 10.1016/j.jmbbm.2013.08.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 07/28/2013] [Accepted: 08/05/2013] [Indexed: 11/28/2022]
Abstract
Promising treatment approaches in repairing tissue defects include implementation of regenerative medicine strategies, particularly delivery of preadipocytes to sites where adipose tissue damage needs to be repaired or where fat needs to be generated. In this study, we suggest that the injectable hyaluronic acid/adipic acid dihydrazide (HA/ADH) hydrogel may be an adipose-tissue-like material in terms of biological compatibility as well as mechanical behavior. First, we show that the hydrogel enables and supports growth, proliferation and differentiation of 3T3-L1 preadipocytes. Second, given that adipose tissue is a weight-bearing biological structure, we investigate the large deformation mechanical behavior of the hydrogel with and without embedded preadipocytes, by performing confined and unconfined compression tests and then calibrating a strain energy density (SED) function to the results. Four test groups were examined: (1) Hydrogel specimens right after the preparation without cells, (2) and (3) 3-days-cultured hydrogel specimens with and without cells, respectively, and (4) 6-days-cultured hydrogel specimens with cells. A one-term Ogden SED was found to adequately describe the hyperelastic behavior of the hydrogel specimens in all experimental groups. Importantly, we found that the mechanical properties of the hydrogel, when subjected to compression, are in good agreement with those of native adipose tissue, with the better fit occurring 3-6 days after preparation of the hydrogel. Third, computational finite element studies of the mechanical (stress-strain) behavior of the HA/ADH hydrogel when containing mature adipocytes indicated that the stiffnesses of the constructs were mildly affected by the presence of the adipocytes. Hence, we conclude that injectable HA/ADH hydrogel may serve as a vessel for protecting preadipocytes during, and at a short-term after delivery to native tissues, e.g. in research towards regenerative medicine in tissue reconstructions.
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Affiliation(s)
- Naama Shoham
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
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30
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Olesen CG, Pennisi CP, de Zee M, Zachar V, Rasmussen J. Elliptical posts allow for detailed control of non-equibiaxial straining of cell cultures. J Tissue Viability 2013; 22:52-6. [DOI: 10.1016/j.jtv.2013.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 02/26/2013] [Accepted: 02/27/2013] [Indexed: 01/19/2023]
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31
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Leopold E, Gefen A. Changes in permeability of the plasma membrane of myoblasts to fluorescent dyes with different molecular masses under sustained uniaxial stretching. Med Eng Phys 2013; 35:601-7. [DOI: 10.1016/j.medengphy.2012.07.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 06/28/2012] [Accepted: 07/12/2012] [Indexed: 01/27/2023]
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32
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Shahar R, Dean MN. The enigmas of bone without osteocytes. BONEKEY REPORTS 2013; 2:343. [PMID: 24422081 DOI: 10.1038/bonekey.2013.77] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 03/22/2013] [Indexed: 12/11/2022]
Abstract
One of the hallmarks of tetrapod bone is the presence of numerous cells (osteocytes) within the matrix. Osteocytes are vital components of tetrapod bone, orchestrating the processes of bone building, reshaping and repairing (modeling and remodeling), and probably also participating in calcium-phosphorus homeostasis via both the local process of osteocytic osteolysis, and systemic effect on the kidneys. Given these critical roles of osteocytes, it is thought-provoking that the entire skeleton of many fishes consists of bone material that does not contain osteocytes. This raises the intriguing question of how the skeleton of these animals accomplishes the various essential functions attributed to osteocytes in other vertebrates, and raises the possibility that in acellular bone some of these functions are either accomplished by non-osteocytic routes or not necessary at all. In this review, we outline evidence for and against the fact that primary functions normally ascribed to osteocytes, such as mechanosensation, regulation of osteoblast/clast activity and mineral metabolism, also occur in fish bone devoid of these cells, and therefore must be carried out through alternative and perhaps ancient pathways. To enable meaningful comparisons with mammalian bone, we suggest thorough, phylogenetic examinations of regulatory pathways, studies of structure and mechanical properties and surveys of the presence/absence of bone cells in fishes. Insights gained into the micro-/nanolevel structure and architecture of fish bone, its mechanical properties and its physiology in health and disease will contribute to the discipline of fish skeletal biology, but may also help answer questions of basic bone biology.
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Affiliation(s)
- Ron Shahar
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem , Israel
| | - Mason N Dean
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces , Potsdam, Germany
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33
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Extracellular Matrix Remodeling and Mechanical Stresses as Modulators of Adipose Tissue Metabolism and Inflammation. THE MECHANOBIOLOGY OF OBESITY AND RELATED DISEASES 2013. [DOI: 10.1007/8415_2013_172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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34
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Shoham N, Gefen A. The influence of mechanical stretching on mitosis, growth, and adipose conversion in adipocyte cultures. Biomech Model Mechanobiol 2012; 11:1029-45. [DOI: 10.1007/s10237-011-0371-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 12/30/2011] [Indexed: 12/14/2022]
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