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1.
Aesthetic Plast Surg ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814346

RESUMO

BACKGROUND: Breast lipofilling, a popular cosmetic and reconstructive procedure, involves the transplantation of autologous fat to enhance breast volume and contour. Despite its widespread use, cell processing and the aftertreatment remain controversial. This study investigates the pressure applied by a compression bra and reports in vitro stress tests of processed and unprocessed fat cells. METHODS: Clinical bra pressure measurements were conducted on a cohort of 45 patients following lipofilling, reduction mammoplasties and DIEP flaps. Laboratory analysis included cell vitality testing using Resazurin assays of processed and unprocessed fat cells after exposure to mechanical or hyperbaric pressure. RESULTS: Our findings show a mean overall pressure value of the compression bra for all patients of 6.7 ± 5.7 mmHg (range 0-35). Cell processing is superior to sedimentation only regarding fat cell vitality. However, neither mechanical pressure within the specified range nor hyperbaric oxygen exposure significantly affected fat graft survival as measured by Resazurin assays. CONCLUSION: The in vitro measurements showed that it was impossible to harm fat cells with external pressure during lipofilling procedures, regardless of their processing. In the clinical context, the compression bra applied pressure values deceeding the perfusion pressure and may therefore not diminish oxygen supply nor harm the transplanted cells. Therefore, we recommend the use of a compression bra for all lipofilling procedures around the breast. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266.

2.
Int J Mol Sci ; 25(4)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38396867

RESUMO

Lipofilling is an option for breast reconstruction after tumor resection to avoid the complications of an implant-based reconstruction. Although some concerns exist regarding the oncological safety of tissue rich in mesenchymal stem cells with their proangiogenic and proliferation-supportive properties, there are also reports that adipose-tissue-derived stem cells can exhibit antitumoral properties. We isolated primary adipose-tissue-derived stem cells. Both conditioned medium and exosomes were harvested from the cell culture and used to treat the breast cancer cell line MCF-7. Cell viability, cytotoxicity, and gene expression of MCF-7 cells in response to the indirect co-culture were evaluated. MCF-7 cells incubated with exosomes from adipose-tissue-derived stem cells show reduced cell viability in comparison to MCF-7 cells incubated with adipose-tissue-derived stem-cell-conditioned medium. Expression of proapoptotic genes was upregulated, and expression of antiapoptotic genes was downregulated. The debate about the oncological safety of autologous fat grafting after tumor resection continues. Here, we show that exosomes from adipose-tissue-derived stem cells exhibit some antitumoral properties on breast cancer cell line MCF-7.


Assuntos
Neoplasias da Mama , Exossomos , Humanos , Feminino , Exossomos/genética , Meios de Cultivo Condicionados/farmacologia , Meios de Cultivo Condicionados/metabolismo , Tecido Adiposo/metabolismo , Células-Tronco , Linhagem Celular Tumoral , Expressão Gênica , Neoplasias da Mama/metabolismo
3.
Int J Mol Sci ; 24(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38139266

RESUMO

Lipedema is a chronic condition characterized by disproportionate and symmetrical enlargement of adipose tissue, predominantly affecting the lower limbs of women. This study investigated the use of metabolomics in lipedema research, with the objective of identifying complex metabolic disturbances and potential biomarkers for early detection, prognosis, and treatment strategies. The study group (n = 25) comprised women diagnosed with lipedema. The controls were 25 lean women and 25 obese females, both matched for age. In the patients with lipedema, there were notable changes in the metabolite parameters. Specifically, lower levels of histidine and phenylalanine were observed, whereas pyruvic acid was elevated compared with the weight controls. The receiver operating characteristic (ROC) curves for the diagnostic accuracy of histidine, phenylalanine, and pyruvic acid concentrations in distinguishing between patients with lipedema and those with obesity but without lipedema revealed good diagnostic ability for all parameters, with pyruvic acid being the most promising (area under the curve (AUC): 0.9992). Subgroup analysis within matched body mass index (BMI) ranges (30.0 to 39.9 kg/m2) further revealed that differences in pyruvic acid, phenylalanine, and histidine levels are likely linked to lipedema pathology rather than BMI variations. Changes in low-density lipoprotein (LDL)-6 TG levels and significant reductions in various LDL-2-carried lipids of patients with lipedema, compared with the lean controls, were observed. However, these lipids were similar between the lipedema patients and the obese controls, suggesting that these alterations are related to adiposity. Metabolomics is a valuable tool for investigating lipedema, offering a comprehensive view of metabolic changes and insights into lipedema's underlying mechanisms.


Assuntos
Lipedema , Humanos , Feminino , Lipedema/metabolismo , Histidina , Ácido Pirúvico , Obesidade , Lipídeos , Fenilalanina
4.
J Tissue Viability ; 32(4): 613-617, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37414709

RESUMO

BACKGROUND: The use of negative pressure wound therapy (NPWT) in superinfected wounds is controversial. The mechanism of action is unclear, but recent studies have shown lower atmospheric oxygen levels within the dressing. Therefore, different oxygen-favoring bacteria and fungi might benefit or face impaired thriving conditions. The aim of this in vitro study is to investigate the influence of NPWT on bacterial and fungal growth. METHODS: Salmonella enterica subsp. enterica serovar Typhimurium, Pseudomonas aeruginosa and Candida albicans strains were cultured on concentrated agars and attached to a standard NPWT-device. After 48 hours, colonies were separately harvested from the agar and foam. Optical density (OD) was obtained in order to estimate bacterial loads. RESULTS: For all tested microorganisms, no overall significant differences were found compared to controls. Subanalysis showed lower OD levels from the agar beneath the foam in the NPWT-group. CONCLUSION: NPWT removed bacteria and fungi from the wound surface but accumulation is found within the foam. The use of NPWT showed no influence on bacterial or fungal growth selection. With superinfected wounds, the use of NPWT should thoroughly be evaluated as toxins and virulence factors may not fully be evacuated.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Infecção dos Ferimentos , Humanos , Infecção dos Ferimentos/terapia , Ágar , Oxigênio , Bactérias
5.
Microvasc Res ; 133: 104072, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32949573

RESUMO

BACKGROUND: The process of angiogenesis is a key element for tumor growth and proliferation and therefore one of the determining factors for aggressiveness and malignancy. A better understanding of the underlying processes of tumor induced angiogenesis is crucial for superior cancer treatment. Furthermore, the PeriCam perfusion speckle imager (PSI) system high resolution (HR) model by PERIMED presents a noninvasive method for semi-quantitative measurement of blood perfusion, based on laser speckle contrast analysis (LASCA). Aim of the present study was to utilize the chick chorioallantoic membrane (CAM) model as an in-ovo-tumor-model which enables rapid neovascularization of tumors while allowing real-time observation of the microcirculation via LASCA. METHODS: Fertilized chicken eggs were grafted with embryonal/alveolar rhabdomyosarcoma cells or primary sarcoma tumors. The blood perfusion was measured before and after tumor growth using LASCA. The procedure is accelerated and simplified through the integrated PIMSoft software which provides real-time graphs and color-coded images during the measurement. RESULTS: Sarcoma cells and primary sarcoma tumors exhibited satisfactory growth processes on the CAM. LASCA visualized microcirculation accurately and enabled an extensive investigation of the angiogenic potential of sarcoma cells on the CAM. We were able to show that sarcoma cells and primary sarcoma tumors induced larger quantities of neovasculature on the CAM than the controls. CONCLUSIONS: The utilization of LASCA for the investigation of tumor angiogenesis within the CAM model appears to be a highly beneficial, cost-efficient and easily practicable procedure. The proposed model can be used as a drug-screening model for individualized cancer therapy, especially with regards to anti-angiogenic agents.


Assuntos
Membrana Corioalantoide/irrigação sanguínea , Fluxometria por Laser-Doppler , Neovascularização Patológica , Imagem de Perfusão , Rabdomiossarcoma Alveolar/irrigação sanguínea , Rabdomiossarcoma Embrionário/irrigação sanguínea , Sarcoma/irrigação sanguínea , Animais , Velocidade do Fluxo Sanguíneo , Linhagem Celular Tumoral , Embrião de Galinha , Xenoenxertos , Humanos , Fluxo Sanguíneo Regional , Fatores de Tempo , Carga Tumoral , Células Tumorais Cultivadas
6.
Aesthetic Plast Surg ; 44(3): 855-861, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32157376

RESUMO

INTRODUCTION: Multiple symmetric lipomatosis (MSL) (syn.: Launois-Bensaude Syndrome, benign symmetric lipomatosis) is a rare disease of fatty tissue. The pathophysiology of MSL still remains unclear, although several approaches have been described in order to understand it. Beside morphological characteristics and some molecular cell biological approaches, little is known about the histological and immunohistochemical characterization of adipose tissue from patients with MSL. METHODS: From the 45 patients with MSL in our database, 10 were included in the study. Fat tissue samples were collected from affected and unaffected areas. The forearm served as a control area as this area is not affected in MSL. The specimens were analyzed after selected stainings were taken (hematoxylin-eosin = HE, Elastica van Gieson, Ladewig, CD200, CIDEA, myf5, p107, Prdm16, Sca-1, syndecan, UCP1, MAC387, Glut4). RESULTS: In patients suffering from MSL, no macroscopic or microscopic morphological difference could be found between affected and unaffected adipose tissue in HE stainings. The majority of samples showed positivity for UCP1 (9/10 clinically affected tissues, 7/10 clinically unaffected tissues) and CD200. CONCLUSION: Marker profiles support the hypothesis that affected adipose tissue derives from brown or beige adipose tissue rather than from white fat. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Assuntos
Tecido Adiposo Bege , Lipomatose Simétrica Múltipla , Tecido Adiposo , Humanos , Lipomatose Simétrica Múltipla/cirurgia
7.
Int J Mol Sci ; 18(8)2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28829358

RESUMO

Platelet-rich plasma is a current subject of studies on chronic wound healing therapy due to possible pro-angiogenic effects. Microvascular compromise represents the major component in radiogenic wound healing complications. The effects of platelet-rich plasma on irradiated cells of the cutaneous wound healing process are poorly understood so far. In this study, the interaction of endothelial cells and adipose-derived stem cells in conjunction with treatment with platelet-rich plasma is investigated in the context of radiation effects. Therefore, the expression of surface-marker CD90 and CD31 was determined. Moreover, cell proliferation and viability after external radiation was analyzed with and without treatment by platelet-rich plasma.


Assuntos
Plasma Rico em Plaquetas , Lesões por Radiação/patologia , Lesões por Radiação/terapia , Cicatrização , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Biomarcadores , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais/efeitos da radiação , Humanos , Imunofenotipagem , Radioterapia/efeitos adversos
8.
Acta Odontol Scand ; 73(2): 93-100, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25376664

RESUMO

OBJECTIVE: Dental stem cells (SCs) will be increasingly used for bone regeneration in the future. Recently, dental follicle cells (DFCs) from retained human third molars have been isolated and characterized as osteogenic progenitors. Although these results are promising for regenerative dentistry, molecular processes during osteogenic differentiation are not yet well understood. MATERIALS AND METHODS: This study compared DFCs before and during osteogenic differentiation. ALP activity was measured and cells were stained with alizarin red. Real-time RT-PCRs for osteogenic markers were done. The genome-wide expression profile was evaluated using a microarray. RESULTS: DFCs showed strong mineralization and increased expression of osteogenic marker genes during osteogenic differentiation. A microarray analysis showed regulated genes before and in the process of osteogenic differentiation (day 7). Several regulated genes in DFCs were associated with skeletal development. Bioinformatic analysis revealed a number of factors associated with dental follicle osteogenic differentiation. Osteogenic differentiation affected expression levels of the transcriptional regulators FOXC2 and ZNF219. CONCLUSION: In conclusion, the results yielded new objectives for further studies on transcription factors like FOXC2 or ETV1 and their role in dental SCs during osteogenic differentiation.


Assuntos
Saco Dentário/citologia , Perfilação da Expressão Gênica , Células-Tronco/fisiologia , Fosfatase Alcalina/análise , Regeneração Óssea/genética , Calcificação Fisiológica/genética , Cálcio/análise , Técnicas de Cultura de Células , Diferenciação Celular/genética , Proteínas de Ligação a DNA/genética , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica/genética , Marcadores Genéticos/genética , Estudo de Associação Genômica Ampla , Humanos , Análise em Microsséries , Osteogênese/genética , Transcrição Gênica/genética , Dedos de Zinco/genética
9.
Cell Tissue Res ; 357(3): 695-705, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24816988

RESUMO

Dental follicle cells (DFCs) can be artificially differentiated into mineralizing cells. With a dexamethasone-based differentiation protocol, transcription factors ZBTB16 and NR4A3 are highly upregulated but Runx2 and other osteogenic marker genes are not. Previous studies have suggested the involvement of a Runx2-independent differentiation pathway. The objective of this study is to further elucidate this mechanism. Differentiation of DFCs was examined by alkaline phosphatase (ALP) staining and ALP activity measurement, by Alizarin Red S staining and by real-time reverse transcription plus the polymerase chain reaction. ZBTB16 was overexpressed by using a transient transfection method. Resulting genome-wide gene expression changes were assessed by microarray. ZBTB16 and Runx2 were inhibited by short interfering RNA transfection. Promoter binding of ZBTB16 was evaluated by chromatin immunoprecipitation. Downregulation of Runx2 had no effect on dexamethasone-induced differentiation but was effective on BMP2-induced differentiation. Downregulation of ZBTB16, however, impaired dexamethasone-induced differentiation. Genes that were upregulated by dexamethasone induction were also upregulated by ZBTB16 overexpression. Genes that were not upregulated during dexamethasone-induced differentiation were also not regulated by ZBTB16 overexpression. ZBTB16 bound directly to the promoter regions of osterix and NR4A3 but not that of Runx2. Overexpression of ZBTB16 led to changes in the gene expression profile, whereby upregulated genes were overrepresented in osteogenesis-associated biological processes. Our findings suggest that, in DFCs, a Runx2-independent differentiation mechanism exists that is regulated by ZBTB16.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Saco Dentário/citologia , Saco Dentário/metabolismo , Dexametasona/farmacologia , Fatores de Transcrição Kruppel-Like/metabolismo , Osteogênese/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Sítios de Ligação , Biomarcadores/metabolismo , Imunoprecipitação da Cromatina , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Saco Dentário/efeitos dos fármacos , Humanos , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/genética , Minerais/metabolismo , Regiões Promotoras Genéticas/genética , Proteína com Dedos de Zinco da Leucemia Promielocítica , Ligação Proteica/efeitos dos fármacos , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Receptores dos Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/metabolismo , Fator de Transcrição Sp7 , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos , Adulto Jovem
10.
Odontology ; 102(2): 154-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23836050

RESUMO

Dental stem cells, especially dental follicle cells (DFCs) as precursor cells for the periodontium have interesting prospects for regenerative dentistry. During periodontitis, butyrate as a bacterial metabolite and inflammatory agent is often found in millimolar concentrations in periodontal pockets. This study evaluates the effects of butyrate on the proliferation and osteogenic differentiation of DFCs. We assessed cell viability/proliferation (BCA assay) and osteogenic differentiation (ALP activity, alizarin staining and RT PCR) of DFCs in vitro after butyrate supplementation. Butyrate concentrations of 20 mM or higher are toxic for DFCs. At a non-toxic concentration, butyrate promotes the expression of alkaline phosphatase and collagen type-1 but inhibits the formation of calcified nodules and the induction of RUNX2 and osteocalcin under osteogenic differentiation conditions. In conclusion, DFCs are resistant to physiological high concentrations of butyrate. Butyrate facilitates the osteogenic differentiation of DFCs in early stages but inhibits calcification at later stages of the differentiation process.


Assuntos
Ácido Butírico/farmacologia , Diferenciação Celular/efeitos dos fármacos , Saco Dentário/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Células Cultivadas , Saco Dentário/citologia , Humanos
11.
Acta Odontol Scand ; 72(4): 241-50, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24074394

RESUMO

OBJECTIVE: Bacterial adhesion on and cytotoxicity of eight luting agents used for implant-supported restorations were investigated. MATERIALS AND METHOD: Surface roughness (Ra), surface free energy (SFE) values and three-dimensional images by atomic-force microscopy of circular specimens were determined. Bacterial suspensions of Streptococcus sanguinis and Streptococcus epidermidis were incubated at 37°C for 2 h. Adhering bacteria were examined with fluorescence dye CytoX-Violet, stained with 4',6-diamidino-2-phenylindole (DAPI) and visualized by fluorescence-microscopy. Cytotoxicity-testing was done with WST-1-tests (water soluble tetrazolium). No significant differences, neither with regard to Ra nor regarding SFE were determined. RESULTS: Adherence of S. sanguinis was less on titanium, TempBondNE and TempBond. TempBond, TempBondNE, RelyX Unicem and Implantlink Semi Classic presented low amounts of S. epidermidis. WST-testing showed high cytotoxic potential of Harvard, Aqualox, TempBondNE and TempBond. No combination of low adherent bacteria with low cytotoxicity was found. CONCLUSION: From a biological in-vitro perspective, none of the cements may be recommended for implant-supported restorations.


Assuntos
Aderência Bacteriana , Cimentos Dentários , Implantes Dentários , Restauração Dentária Permanente , Biofilmes , Microscopia de Fluorescência , Staphylococcus epidermidis/isolamento & purificação
12.
PNAS Nexus ; 3(6): pgae202, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38840799

RESUMO

To assess cellular behavior within heterogeneous tissues, such as bone, skin, and nerves, scaffolds with biophysical gradients are required to adequately replicate the in vivo interaction between cells and their native microenvironment. In this study, we introduce a strategy for depositing ultrathin films comprised of laminin-111 with precisely controlled biophysical gradients onto planar substrates using the Langmuir-Blodgett (LB) technique. The gradient is created by controlled desynchronization of the barrier compression and substrate withdrawal speed during the LB deposition process. Characterization of the films was performed using techniques such as atomic force microscopy and confocal fluorescence microscopy, enabling the comprehensive analysis of biophysical parameters along the gradient direction. Furthermore, human adipose-derived stem cells were seeded onto the gradient films to investigate the influence of protein density on cell attachment, showing that the distribution of the cells can be modulated by the arrangement of the laminin at the air-water interface. The presented approach not only allowed us to gain insights into the intricate interplay between biophysical cues and cell behavior within complex tissue environments, but it is also suited as a screening approach to determine optimal protein concentrations to achieve a target cellular output.

13.
Cells ; 13(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38607053

RESUMO

BACKGROUND: Extracellular vesicles are pivotal mediators in intercellular communication, facilitating the exchange of biological information among healthy, pathological and tumor cells. Between the diverse subtypes of extracellular vesicles, exosomes have unique properties and clinical and therapeutical applications. Breast cancer ranks as one of the most prevalent malignancies across the globe. Both the tumor core and its surrounding microenvironment engage in a complex, orchestrated interaction that facilitates cancer's growth and spread. METHODS: The most significant PubMed literature about extracellular vesicles and Adipose-Derived Stem Cell Exosomes and breast cancer was selected in order to report their biological properties and potential applications, in particular in treating triple-negative breast cancer. RESULTS: Adipose-Derived Stem Cell Exosomes represent a potential tool in targeting triple-negative breast cancer cells at three main levels: the tumor core, the tumor microenvironment and surrounding tissues, including metastases. CONCLUSIONS: The possibility of impacting triple-negative breast cancer cells with engineered Adipose-Derived Stem Cell Exosomes is real. The opportunity to translate our current in vitro analyses into a future in vivo scenario is even more challenging.


Assuntos
Exossomos , Vesículas Extracelulares , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/terapia , Adipócitos , Células-Tronco , Microambiente Tumoral
14.
Artigo em Inglês | MEDLINE | ID: mdl-38578884

RESUMO

Myocardial infarction refers to the ischemic necrosis of myocardium, characterized by a sharp reduction or interruption of blood flow in the coronary arteries due to the coronary artery occlusion, resulting in severe and prolonged ischemia in the corresponding myocardium and ultimately leading to ischemic necrosis of the myocardium. Given its high risk, it is considered as one of the most serious health threats today. In current clinical practice, multiple approaches have been explored to diminish myocardial oxygen consumption and alleviate symptoms, but notable success remains elusive. Accumulated clinical evidence has showed that the implantation of mesenchymal stem cell for treating myocardial infarction is both effective and safe. Nevertheless, there persists controversy and variability regarding the standardizing MSC transplantation protocols, optimizing dosage, and determining the most effective routes of administration. Addressing these remaining issues will pave the way of integration of MSCs as a feasible mainstream cardiac treatment.

15.
Differentiation ; 83(1): 10-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22099172

RESUMO

Dental follicle is a loose connective tissue that surrounds the developing tooth. Dental follicle cells (DFCs) have a promising potential for tissue engineering applications including periodontal and bone regeneration. However, little is known about the molecular mechanisms underlying osteogenic differentiation. In a previous study we detected that more than 35% of genes that are regulated during osteogenic differentiation of DFCs have promoter binding sites for the transcription factors TP53 and SP1. However, the role of these transcription factors in dental stem cells is still unknown. We hypothesize that both factors influence the processes of cell proliferation and differentiation in dental stem cells. Therefore, we transiently transfected DFCs and dental pulp stem cells (SHED; Stem cells from human exfoliated decidiuous teeth) with expression vectors for these transcription factors. After overexpression of SP1 and TP53, SP1 influenced cell proliferation and TP53 osteogenic differentiation in both dental cell types. The effects on cell proliferation and differentiation were less pronounced after siRNA mediated silencing of TP53 and SP1. This indicates that the effects we observed after TP53 and SP1 overexpression are indirect and subject of complex regulation. Interestingly, upregulated biological processes in DFCs after TP53-overexpression resemble the downregulated biological processes in SHED after SP1-overexpression. Here, regulated processes are involved in cell motility, wound healing and programmed cell death. In conclusion, our study demonstrates that SP1 and TP53 influence cell proliferation and differentiation and similar biological processes in both SHED and DFCs.


Assuntos
Polpa Dentária/citologia , Saco Dentário/citologia , Imunoglobulinas/metabolismo , Células-Tronco/citologia , Proteína Supressora de Tumor p53/metabolismo , Regeneração Óssea , Diferenciação Celular/genética , Proliferação de Células , Células Cultivadas , Polpa Dentária/crescimento & desenvolvimento , Saco Dentário/crescimento & desenvolvimento , Regulação da Expressão Gênica , Inativação Gênica , Humanos , Imunoglobulinas/genética , Osteogênese/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Células-Tronco/metabolismo , Engenharia Tecidual , Esfoliação de Dente/genética , Esfoliação de Dente/metabolismo , Proteína Supressora de Tumor p53/genética
16.
Cells ; 12(4)2023 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-36831259

RESUMO

With a history of more than 100 years of different applications in various scientific fields, the chicken chorioallantoic membrane (CAM) assay has proven itself to be an exceptional scientific model that meets the requirements of the replacement, reduction, and refinement principle (3R principle). As one of three extraembryonic avian membranes, the CAM is responsible for fetal respiration, metabolism, and protection. The model provides a unique constellation of immunological, vascular, and extracellular properties while being affordable and reliable at the same time. It can be utilized for research purposes in cancer biology, angiogenesis, virology, and toxicology and has recently been used for biochemistry, pharmaceutical research, and stem cell biology. Stem cells and, in particular, mesenchymal stem cells derived from adipose tissue (ADSCs) are emerging subjects for novel therapeutic strategies in the fields of tissue regeneration and personalized medicine. Because of their easy accessibility, differentiation profile, immunomodulatory properties, and cytokine repertoire, ADSCs have already been established for different preclinical applications in the files mentioned above. In this review, we aim to highlight and identify some of the cross-sections for the potential utilization of the CAM model for ADSC studies with a focus on wound healing and tissue engineering, as well as oncological research, e.g., sarcomas. Hereby, the focus lies on the combination of existing evidence and experience of such intersections with a potential utilization of the CAM model for further research on ADSCs.


Assuntos
Membrana Corioalantoide , Pesquisa com Células-Tronco , Animais , Engenharia Tecidual , Tecido Adiposo/metabolismo
17.
Cells ; 11(19)2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36231121

RESUMO

The good availability and the large content of adult stem cells in adipose tissue has made it one of the most interesting tissues in regenerative medicine. Although lipofilling is one of the most frequent procedures in plastic surgery, the method still struggles with high absorption rates and volume losses of up to 70%. Therefore, many efforts have been made to optimize liposuction and to process the harvested tissue in order to increase fat graft retention. Because of their immunomodulatory properties, their cytokine secretory activity, and their differentiation potential, enrichment with adipose tissue-derived stem cells was identified as a promising tool to promote transplant survival. Here, we review the important parameters for lipofilling optimization. Finally, we present a new method for the enrichment of lipoaspirate with adipose tissue-derived stem cells and discuss the parameters that contribute to fat graft survival.


Assuntos
Lipectomia , Rejuvenescimento , Tecido Adiposo , Citocinas , Sobrevivência de Enxerto , Lipectomia/métodos
18.
Cells ; 11(16)2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-36010620

RESUMO

Autologous lipotransfer is a promising method for tissue regeneration, because white adipose tissue contains a heterogeneous cell population, including mesenchymal stem cells, endothelial cells, immune cells, and adipocytes. In order to improve the outcome, adipose tissue can be processed before application. In this study, we investigated changes caused by mechanical processing. Lipoaspirates were processed using sedimentation, first-time centrifugation, shear-force homogenization, and second-time centrifugation. The average adipocyte size, stromal vascular cell count, and adipocyte depot size were examined histologically at every processing step. In addition, the adipose derived stem cells (ADSCs) were isolated and differentiated osteogenically and adipogenically. While homogenization causes a disruption of adipocyte depots, the shape of the remaining adipocytes is not changed. On average, these adipocytes are smaller than the depot adipocytes, they are surrounded by the ECM, and therefore mechanically more stable. The volume loss of adipocyte depots leads to a significant enrichment of stromal vascular cells such as ADSCs. However, the mechanical processing does not change the potential of the ADSCs to differentiate adipogenically or osteogenically. It thus appears that mechanically processed lipoaspirates are promising for the reparation of even mechanically stressed tissue as that found in nasolabial folds. The changes resulting from the processing correspond more to a filtration of mechanically less stable components than to a manipulation of the tissue.


Assuntos
Adipócitos , Células Endoteliais , Tecido Adiposo , Tecido Adiposo Branco , Células-Tronco
19.
Artigo em Inglês | MEDLINE | ID: mdl-36502314

RESUMO

BACKGROUND: Recent studies have demonstrated that local application of corticosteroids reduces wound exudation following abdominoplasty and other reconstructive surgical procedures. On the other hand, corticosteroids might provoke wound healing disturbances due to their immunosuppressive effects. OBJECTIVE: The main objective of this study was to gain further information about the impact of the corticosteroid triamcinolone on cell migration in abdominoplasty patients. METHODS: An in-vitro scratch assay wound healing model was applied to observe cell migration of fibroblasts cultured with nutrient medium containing human seroma aspirate±triamcinolone. RESULTS: There were no significant differences regarding cell migration when fibroblasts were incubated with triamcinolone + seroma containing culture medium compared to seroma containing culture medium without triamcinolone. CONCLUSIONS: The performed in-vitro study suggests that triamcinolone does not decelerate fibroblast cell migration which is considered as a surrogate of wound healing.

20.
Cells ; 11(18)2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36139462

RESUMO

The lack of supportive Schwann cells in segmental nerve lesions seems to be one cornerstone for the problem of insufficient nerve regeneration. Lately, adipose-tissue-derived stem cells (ASCs) differentiated towards SC (Schwann cell)-like cells seem to fulfill some of the needs for ameliorated nerve recovery. In this study, three differentiation protocols were investigated for their ability to differentiate ASCs from rats into specialized SC phenotypes. The differentiated ASCs (dASCs) were compared for their expressions of neurotrophins (NGF, GDNF, BDNF), myelin markers (MBP, P0), as well as glial-marker proteins (S100, GFAP) by RT-PCR, ELISA, and Western blot. Additionally, the influence of the medium conditioned by dASCs on a neuron-like cell line was evaluated. The dASCs were highly diverse in their expression profiles. One protocol yielded relatively high expression rates of neurotrophins, whereas another protocol induced myelin-marker expression. These results were reproducible when the ASCs were differentiated on surfaces potentially used for nerve guidance conduits. The NGF secretion affected the neurite outgrowth significantly. It remains uncertain what features of these SC-like cells contribute the most to adequate functional recovery during the different phases of nerve recovery. Nevertheless, therapeutic applications should consider these diverse phenotypes as a potential approach for stem-cell-based nerve-injury treatment.


Assuntos
Fator de Crescimento Neural , Neuritos , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator de Crescimento Neural/metabolismo , Regeneração Nervosa/fisiologia , Neuritos/metabolismo , Ratos , Células-Tronco
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