PEG-Plasma Hydrogels Increase Epithelialization Using a Human Ex Vivo Skin Model

In vitro cell culture methods are used extensively to study cellular migration, proliferation, and differentiation, which play major roles in wound healing but the results often do not translate to the in vivo environment. One alternative would be to establish an ex vivo model utilizing human discarded skin to evaluate therapies in a more natural setting. The purpose of this study was to institute such a model by creating ‘wounds’ in the center of a piece of discarded skin and treating them with three different biomaterials: collagen, polyethylene glycol (PEG)-fibrin, or PEG-platelet free plasma (PFP). Explants were cultured for 14 days with supernatant and microscopy images collected every 3 days to assess cytotoxicity and epithelialization. After 14 days, the explants were fixed, sectioned, and stained for cytokeratin-10 (CK-10), alpha-smooth muscle actin (α-SMA), and wheat germ (WG). Compared to controls, similar levels of cytotoxicity were detected for 12 days which decreased slightly at day 14. The PEG-PFP hydrogel-treated wounds epithelialized faster than other treatments at days 6 to 14. A 6-8 cell layer thick CK-10+ stratified epidermis had developed over the PEG-PFP hydrogel and cells co-stained by WG and α-SMA were observed within the hydrogel. An ex vivo model was established that can be used practically to screen different therapies exploring wound healing.

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Cold Plasma Treatment Promotes Full-thickness Healing of Skin Wounds in Murine Models

The International Journal of Lower Extremity Wounds ◽

10.1177/15347346211002144 ◽

2021 ◽

pp. 153473462110021

Author(s):

Joon M. Jung ◽

Hae K. Yoon ◽

Chang J. Jung ◽

Soo Y. Jo ◽

Sang G. Hwang ◽

...

Keyword(s):

Wound Healing ◽

Plasma Treatment ◽

Cold Plasma ◽

Smooth Muscle Actin ◽

Treated Group ◽

Control Group ◽

Alpha Smooth Muscle Actin ◽

Skin Wound Healing

Cold plasma can be beneficial for promoting skin wound healing and has a high potential of being effectively used in treating various wounds. Our aim was to verify the effect of cold plasma in accelerating wound healing and investigate its underlying mechanism in vitro and in vivo. For the in vivo experiments, 2 full-thickness dermal wounds were created in each mouse (n = 30). While one wound was exposed to 2 daily plasma treatments for 3 min, the other wound served as a control. The wounds were evaluated by imaging and histological analyses at 4, 7, and 11 days post the wound infliction process. Immunohistochemical studies were also performed at the same time points. In vitro proliferation and scratch assay using HaCaT keratinocytes and fibroblasts were performed. The expression levels of wound healing–related genes were analyzed by real-time polymerase chain reaction and western blot analysis. On day 7, the wound healing rates were 53.94% and 63.58% for the control group and the plasma-treated group, respectively. On day 11, these rates were 76.05% and 93.44% for the control and plasma-treated groups, respectively, and the difference between them was significant ( P = .039). Histological analysis demonstrated that plasma treatment promotes the formation of epidermal keratin and granular layers. Immunohistochemical studies also revealed that collagen 1, collagen 3, and alpha-smooth muscle actin appeared more abundantly in the plasma-treated group than in the control group. In vitro, the proliferation of keratinocytes was promoted by plasma exposure. Scratch assay showed that fibroblast exposure to plasma increased their migration. The expression levels of collagen 1, collagen 3, and alpha-smooth muscle actin were elevated upon plasma treatment. In conclusion, cold plasma can accelerate skin wound healing and is well tolerated.

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mTOR inhibitors potentially reduce TGF-β2-induced fibrogenic changes in trabecular meshwork cells

Scientific Reports ◽

10.1038/s41598-021-93580-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Nozomi Igarashi ◽

Megumi Honjo ◽

Makoto Aihara

Keyword(s):

Trabecular Meshwork ◽

Transforming Growth Factor ◽

Smooth Muscle Actin ◽

Mtor Inhibitors ◽

In Vivo Model ◽

Type I ◽

Fibrotic Response ◽

Alpha Smooth Muscle Actin

AbstractWe examined the effects of mTOR inhibitors on the fibrotic response induced by transforming growth factor-beta2 (TGF-β2) in cultured human trabecular meshwork (hTM) cells. TGF-β2-induced expression of fibronectin, collagen type I, alpha 1 chain (COL1A1), and alpha-smooth muscle actin (αSMA) in hTM cells was examined in the presence or absence of mTOR inhibitors using quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemistry. The migration rates of hTM cells were examined in the presence of TGF-β2 with or without mTOR inhibitors. An in vitro study showed that the expression of fibronectin, COL1A1, and αSMA was upregulated by TGF-β2 treatment of hTM cells; such upregulation was significantly suppressed by mTOR inhibitors. The inhibitors significantly reduced the migration rate of TGF-β2-stimulated hTM cells. mTOR inhibitors may usefully reduce the fibrotic response of hTM cells and we may have to explore if it is also effective in in vivo model.

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Endothelial-to-Mesenchymal Transition in Human Adipose Tissue Vasculature Alters the Particulate Secretome and Induces Endothelial Dysfunction

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvbaha.119.312826 ◽

2019 ◽

Vol 39 (10) ◽

pp. 2168-2191 ◽

Cited By ~ 3

Author(s):

Bronson A. Haynes ◽

Li Fang Yang ◽

Ryan W. Huyck ◽

Eric J. Lehrer ◽

Joshua M. Turner ◽

...

Keyword(s):

Adipose Tissue ◽

Endothelial Dysfunction ◽

Smooth Muscle Actin ◽

Phenotypic Change ◽

Alpha Smooth Muscle Actin ◽

Mesenchymal Transition ◽

Molecular Features ◽

Endothelial To Mesenchymal Transition

Objective: Endothelial cells (EC) in obese adipose tissue (AT) are exposed to a chronic proinflammatory environment that may induce a mesenchymal-like phenotype and altered function. The objective of this study was to establish whether endothelial-to-mesenchymal transition (EndoMT) is present in human AT in obesity and to investigate the effect of such transition on endothelial function and the endothelial particulate secretome represented by extracellular vesicles (EV). Approach and Results: We identified EndoMT in obese human AT depots by immunohistochemical co-localization of CD31 or vWF and α-SMA (alpha-smooth muscle actin). We showed that AT EC exposed in vitro to TGF-β (tumor growth factor-β), TNF-α (tumor necrosis factor-α), and IFN-γ (interferon-γ) undergo EndoMT with progressive loss of endothelial markers. The phenotypic change results in failure to maintain a tight barrier in culture, increased migration, and reduced angiogenesis. EndoMT also reduced mitochondrial oxidative phosphorylation and glycolytic capacity of EC. EVs produced by EC that underwent EndoMT dramatically reduced angiogenic capacity of the recipient naïve ECs without affecting their migration or proliferation. Proteomic analysis of EV produced by EC in the proinflammatory conditions showed presence of several pro-inflammatory and immune proteins along with an enrichment in angiogenic receptors. Conclusions: We demonstrated the presence of EndoMT in human AT in obesity. EndoMT in vitro resulted in production of EV that transferred some of the functional and metabolic features to recipient naïve EC. This result suggests that functional and molecular features of EC that underwent EndoMT in vivo can be disseminated in a paracrine or endocrine fashion and may induce endothelial dysfunction in distant vascular beds.

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Considerations to Model Heart Disease in Women with Preeclampsia and Cardiovascular Disease

Cells ◽

10.3390/cells10040899 ◽

2021 ◽

Vol 10 (4) ◽

pp. 899

Author(s):

Clara Liu Chung Ming ◽

Kimberly Sesperez ◽

Eitan Ben-Sefer ◽

David Arpon ◽

Kristine McGrath ◽

...

Keyword(s):

Myocardial Infarction ◽

Cardiovascular Disease ◽

Ex Vivo ◽

Myocardial Damage ◽

Cardiovascular Disorder ◽

Model Systems ◽

Ex Vivo Model ◽

Disease Manifestation

Preeclampsia is a multifactorial cardiovascular disorder diagnosed after 20 weeks of gestation, and is the leading cause of death for both mothers and babies in pregnancy. The pathophysiology remains poorly understood due to the variability and unpredictability of disease manifestation when studied in animal models. After preeclampsia, both mothers and offspring have a higher risk of cardiovascular disease (CVD), including myocardial infarction or heart attack and heart failure (HF). Myocardial infarction is an acute myocardial damage that can be treated through reperfusion; however, this therapeutic approach leads to ischemic/reperfusion injury (IRI), often leading to HF. In this review, we compared the current in vivo, in vitro and ex vivo model systems used to study preeclampsia, IRI and HF. Future studies aiming at evaluating CVD in preeclampsia patients could benefit from novel models that better mimic the complex scenario described in this article.

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Considerations to Model Heart Disease in Women with Preeclampsia and Cardiovascular Disease

10.20944/preprints202104.0240.v1 ◽

2021 ◽

Author(s):

Clara Liu Chung Ming ◽

Kimberly Sesperez ◽

Eitan Ben-Sefer ◽

David Arpon ◽

Kristine McGrath ◽

...

Keyword(s):

Myocardial Infarction ◽

Cardiovascular Disease ◽

Ex Vivo ◽

Myocardial Damage ◽

Cardiovascular Disorder ◽

Model Systems ◽

Ex Vivo Model ◽

Disease Manifestation

Preeclampsia is a multifactorial cardiovascular disorder diagnosed after 20 weeks of gestation that is the leading cause of death for both mothers and babies in pregnancy. The pathophysiology remains poorly understood due to variability and unpredictability of disease manifestation when studied in animal models. After preeclampsia, both mothers and offspring have a higher risk of cardiovascular disease (CVD) including myocardial infarction or heart attack and heart failure (HF). Myocardial infarction is an acute myocardial damage that can be treated through reperfusion, however, that therapeutic approach leads to ischemic/reperfusion injury (IRI) often leading to HF. In this review, we compared the current in vivo, in vitro and ex vivo model systems used to study preeclampsia, IRI and HF. Future studies aiming at evaluating CVD in preeclampsia patients could benefit from novel models that better mimic the complex scenario described in this article.

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The MEMIC: An ex vivo system to model the complexity of the tumor microenvironment

Disease Models & Mechanisms ◽

10.1242/dmm.048942 ◽

2021 ◽

Author(s):

Libuše Janská ◽

Libi Anandi ◽

Nell C. Kirchberger ◽

Zoran S. Marinkovic ◽

Logan T. Schachtner ◽

...

Keyword(s):

Tumor Microenvironment ◽

Tumor Cells ◽

Ex Vivo ◽

Tumor Stroma ◽

Stem Cell Differentiation ◽

Blood Stream ◽

Direct Access ◽

Ex Vivo Model

There is an urgent need for accurate, scalable, and cost-efficient experimental systems to model the complexity of the tumor microenvironment. Here, we detail how to fabricate and use the Metabolic Microenvironment Chamber (MEMIC) – a 3D-printed ex vivo model of intratumoral heterogeneity. A major driver of the cellular and molecular diversity in tumors is the accessibility to the blood stream that provides key resources such as oxygen and nutrients. While some tumor cells have direct access to these resources, many others must survive under progressively more ischemic environments as they reside further from the vasculature. The MEMIC is designed to simulate the differential access to nutrients and allows co-culturing different cell types, such as tumor and immune cells. This system is optimized for live imaging and other microscopy-based approaches, and it is a powerful tool to study tumor features such as the effect of nutrient scarcity on tumor-stroma interactions. Due to its adaptable design and full experimental control, the MEMIC provide insights into the tumor microenvironment that would be difficult to obtain via other methods. As a proof of principle, we show that cells sense gradual changes in metabolite concentration resulting in multicellular spatial patterns of signal activation and cell proliferation. To illustrate the ease of studying cell-cell interactions in the MEMIC, we show that ischemic macrophages reduce epithelial features in neighboring tumor cells. We propose the MEMIC as a complement to standard in vitro and in vivo experiments, diversifying the tools available to accurately model, perturb, and monitor the tumor microenvironment, as well as to understand how extracellular metabolites affect other processes such as wound healing and stem cell differentiation.

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Development of Curcumin loaded chitosan polymer based nanoemulsion gel: In vitro, ex vivo evaluation and in vivo wound healing studies

International Journal of Biological Macromolecules ◽

10.1016/j.ijbiomac.2017.03.066 ◽

2017 ◽

Vol 101 ◽

pp. 569-579 ◽

Cited By ~ 30

Author(s):

Lydia Thomas ◽

Foziyah Zakir ◽

Mohd. Aamir Mirza ◽

Md. Khalid Anwer ◽

Farhan Jalees Ahmad ◽

...

Keyword(s):

Wound Healing ◽

Ex Vivo ◽

Nanoemulsion Gel

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Development and Evaluation of Alginate Membranes with Curcumin-Loaded Nanoparticles for Potential Wound-Healing Applications

Pharmaceutics ◽

10.3390/pharmaceutics11080389 ◽

2019 ◽

Vol 11 (8) ◽

pp. 389 ◽

Cited By ~ 10

Author(s):

Mónica C. Guadarrama-Acevedo ◽

Raisa A. Mendoza-Flores ◽

María L. Del Prado-Audelo ◽

Zaida Urbán-Morlán ◽

David M. Giraldo-Gomez ◽

...

Keyword(s):

Wound Healing ◽

Wound Dressing ◽

Clinical Performance ◽

Ex Vivo ◽

High Capacity ◽

Wound Dressings ◽

In Vivo Studies ◽

Potential Use

Non-biodegradable materials with a low swelling capacity and which are opaque and occlusive are the main problems associated with the clinical performance of some commercially available wound dressings. In this work, a novel biodegradable wound dressing was developed by means of alginate membrane and polycaprolactone nanoparticles loaded with curcumin for potential use in wound healing. Curcumin was employed as a model drug due to its important properties in wound healing, including antimicrobial, antifungal, and anti-inflammatory effects. To determine the potential use of wound dressing, in vitro, ex vivo, and in vivo studies were carried out. The novel membrane exhibited the diverse functional characteristics required to perform as a substitute for synthetic skin, such as a high capacity for swelling and adherence to the skin, evidence of pores to regulate the loss of transepidermal water, transparency for monitoring the wound, and drug-controlled release by the incorporation of nanoparticles. The incorporation of the nanocarriers aids the drug in permeating into different skin layers, solving the solubility problems of curcumin. The clinical application of this system would cover extensive areas of mixed first- and second-degree wounds, without the need for removal, thus decreasing the patient’s discomfort and the risk of altering the formation of the new epithelium.

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Detection of allergen-induced airway hyperresponsiveness in isolated mouse lungs

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00011.2005 ◽

2006 ◽

Vol 291 (3) ◽

pp. L466-L472 ◽

Cited By ~ 22

Author(s):

Martin Witzenrath ◽

Birgit Ahrens ◽

Stefanie M. Kube ◽

Armin Braun ◽

Heinz G. Hoymann ◽

...

Keyword(s):

Airway Hyperresponsiveness ◽

Ex Vivo ◽

Whole Body ◽

Strongly Correlated ◽

Ex Vivo Model ◽

Isolated Lungs ◽

Spontaneously Breathing

Airway hyperresponsiveness (AHR) is a hallmark of bronchial asthma. Important features of this exaggerated response to bronchoconstrictive stimuli have mostly been investigated in vivo in intact animals or in vitro in isolated tracheal or bronchial tissues. Both approaches have important advantages but also certain limitations. Therefore, the aim of our study was to develop an ex vivo model of isolated lungs from sensitized mice for the investigation of airway responsiveness (AR). BALB/c mice were sensitized by intraperitoneal ovalbumin (Ova) and subsequently challenged by Ova inhalation. In vivo AR was measured in unrestrained animals by whole body plethysmography after stimulation with aerosolized methacholine (MCh) with determination of enhanced pause ( Penh). Twenty-four hours after each Penh measurement, airway resistance was continuously registered in isolated, perfused, and ventilated lungs on stimulation with inhaled or intravascular MCh or nebulized Ova. In a subset of experiments, in vivo AR was additionally measured in orotracheally intubated, spontaneously breathing mice 24 h after Penh measurement, and lungs were isolated further 24 h later. Isolated lungs of allergen-sensitized and -challenged mice showed increased AR after MCh inhalation or infusion as well as after specific provocation with aerosolized allergen. AR was increased on days 2 and 5 after Ova challenge and had returned to baseline on day 9. AHR in isolated lungs after aerosolized or intravascular MCh strongly correlated with in vivo AR. Pretreatment of isolated lungs with the β2-agonist fenoterol diminished AR. In conclusion, this model provides new opportunities to investigate mechanisms of AHR as well as pharmacological interventions on an intact organ level.

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