scholarly journals Self-assembled ruthenium and osmium nanosystems display potent anticancer profile by interfering with metabolic activity

2021 ◽  
Author(s):  
Mickaël Marloye ◽  
Inam Haider ◽  
Connor J. Moore ◽  
Tyler R. Mertens ◽  
Aude Ingels ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mitochondrial Respiration ◽  
Morphological Changes ◽  
Careful Examination ◽  
Mitochondrial Targeting ◽  
Self Assembling ◽  
Osmium Complexes ◽  
Block Cell Proliferation ◽  
Micromolar Range

We disclose novel amphiphilic ruthenium and osmium complexes that auto-assemble into nanomedicines with potent antiproliferative activity by inhibition of mitochondrial respiration. The self-assembling units were rationally designed from the [M(p-cymene)(1,10-phenanthroline)Cl]PF6 motif (where M is either RuII or OsII) with an appended C16 fatty chain to achieve high cellular activity, nano-assembling and mitochondrial targeting. These amphiphilic complexes block cell proliferation at the sub-micromolar range and are particularly potent towards glioblastoma neurospheres made from patient-derived cancer stem cells. A subcutaneous mouse model using these glioblastoma stem cells highlights one of our C16 OsII nanomedicines as highly successful in vivo. Mechanistically, we show that they act as metabolic poisons, strongly impairing mitochondrial respiration, corroborated by morphological changes and damage to the mitochondria. A genetic strategy based on RNAi gave further insight on the potential involvement of microtubules as part of the induced cell death. In parallel, we present a careful examination of the structural properties of these new amphiphilic metal-based constructs, their reactivity and mechanism.

scholarly journals Inhibiting autophagy targets human leukemic stem cells and hypoxic AML blasts by disrupting mitochondrial homeostasis

2021 ◽  
Vol 5 (8) ◽  
pp. 2087-2100
Author(s):  
Kaitlyn M. Dykstra ◽  
Hannah R. S. Fay ◽  
Ashish C. Massey ◽  
Neng Yang ◽  
Matthew Johnson ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cell Death ◽  
Mitochondrial Respiration ◽  
Prolonged Exposure ◽  
Tumor Burden ◽  
Therapeutic Interventions ◽  
Autophagic Flux ◽  
Mitochondrial Homeostasis ◽  
Nsg Mice

Abstract Leukemia stem cells (LSCs) and therapy-resistant acute myeloid leukemia (AML) blasts contribute to the reinitiation of leukemia after remission, necessitating therapeutic interventions that target these populations. Autophagy is a prosurvival process that allows for cells to adapt to a variety of stressors. Blocking autophagy pharmacologically by using mechanistically distinct inhibitors induced apoptosis and prevented colony formation in primary human AML cells. The most effective inhibitor, bafilomycin A1 (Baf A1), also prevented the in vivo maintenance of AML LSCs in NSG mice. To understand why Baf A1 exerted the most dramatic effects on LSC survival, we evaluated mitochondrial function. Baf A1 reduced mitochondrial respiration and stabilized PTEN-induced kinase-1 (PINK-1), which initiates autophagy of mitochondria (mitophagy). Interestingly, with the autophagy inhibitor chloroquine, levels of enhanced cell death and reduced mitochondrial respiration phenocopied the effects of Baf A1 only when cultured in hypoxic conditions that mimic the marrow microenvironment (1% O2). This indicates that increased efficacy of autophagy inhibitors in inducing AML cell death can be achieved by concurrently inducing mitochondrial damage and mitophagy (pharmacologically or by hypoxic induction) and blocking mitochondrial degradation. In addition, prolonged exposure of AML cells to hypoxia induced autophagic flux and reduced chemosensitivity to cytarabine (Ara-C), which was reversed by autophagy inhibition. The combination of Ara-C with Baf A1 also decreased tumor burden in vivo. These findings demonstrate that autophagy is critical for mitochondrial homeostasis and survival of AML cells in hypoxia and support the development of autophagy inhibitors as novel therapeutic agents for AML.

scholarly journals Rapid Magneto-Sonoporation of Adipose-Derived Cells

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4877
Author(s):  
Miriam Filippi ◽  
Boris Dasen ◽  
Arnaud Scherberich
Keyword(s):  
Stem Cells ◽  
Tissue Repair ◽  
Morphological Changes ◽  
Adipose Derived Stem Cells ◽  
Resonance Imaging ◽  
Membrane Resealing ◽  
First Time ◽  
Stimulation Of

By permeabilizing the cell membrane with ultrasound and facilitating the uptake of iron oxide nanoparticles, the magneto-sonoporation (MSP) technique can be used to instantaneously label transplantable cells (like stem cells) to be visualized via magnetic resonance imaging in vivo. However, the effects of MSP on cells are still largely unexplored. Here, we applied MSP to the widely applicable adipose-derived stem cells (ASCs) for the first time and investigated its effects on the biology of those cells. Upon optimization, MSP allowed us to achieve a consistent nanoparticle uptake (in the range of 10 pg/cell) and a complete membrane resealing in few minutes. Surprisingly, this treatment altered the metabolic activity of cells and induced their differentiation towards an osteoblastic profile, as demonstrated by an increased expression of osteogenic genes and morphological changes. Histological evidence of osteogenic tissue development was collected also in 3D hydrogel constructs. These results point to a novel role of MSP in remote biophysical stimulation of cells with focus application in bone tissue repair.

scholarly journals Thymosin β4-Enhancing Therapeutic Efficacy of Human Adipose-Derived Stem Cells in Mouse Ischemic Hindlimb Model

2020 ◽  
Vol 21 (6) ◽  
pp. 2166
Author(s):  
Jong-Ho Kim ◽  
I-Rang Lim ◽  
Chi-Yeon Park ◽  
Hyung Joon Joo ◽  
Ji-Min Noh ◽  
...  
Keyword(s):  
Stem Cells ◽  
Intracellular Signaling ◽  
Morphological Changes ◽  
Additional Treatment ◽  
Endothelial Differentiation ◽  
Adipose Derived Stem Cells ◽  
Thymosin Β4 ◽  
Differentiation Potential ◽  
Beneficial Effects

Thymosin β4 (Tβ4) is a G-actin sequestering protein that contributes to diverse cellular activities, such as migration and angiogenesis. In this study, the beneficial effects of combined cell therapy with Tβ4 and human adipose-derived stem cells (hASCs) in a mouse ischemic hindlimb model were investigated. We observed that exogenous treatment with Tβ4 enhanced endogenous TMSB4X mRNA expression and promoted morphological changes (increased cell length) in hASCs. Interestingly, Tβ4 induced the active state of hASCs by up-regulating intracellular signaling pathways including the PI3K/AKT/mTOR and MAPK/ERK pathways. Treatment with Tβ4 significantly increased cell migration and sprouting from microbeads. Moreover, additional treatment with Tβ4 promoted the endothelial differentiation potential of hASCs by up-regulating various angiogenic genes. To evaluate the in vivo effects of the Tβ4-hASCs combination on vessel recruitment, dorsal window chambers were transplanted, and the co-treated mice were found to have a significantly increased number of microvessel branches. Transplantation of hASCs in combination with Tβ4 was found to improve blood flow and attenuate limb or foot loss post-ischemia compared to transplantation with hASCs alone. Taken together, the therapeutic application of hASCs combined with Tβ4 could be effective in enhancing endothelial differentiation and vascularization for treating hindlimb ischemia.

scholarly journals Fish primary embryonic stem cells self-assemble into retinal tissue mirroring in vivo early eye development

2021 ◽  
Author(s):  
Lucie Zilova ◽  
Venera Weinhardt ◽  
Tinatini Tavhelidse ◽  
Thomas Thumberger ◽  
Joachim Wittbrodt
Keyword(s):  
Stem Cells ◽  
Embryonic Stem Cells ◽  
Eye Development ◽  
Morphological Changes ◽  
Rapid Development ◽  
Embryonic Stem ◽  
Developmental Time ◽  
Key Steps ◽  
The Impact

AbstractOrganoids derived from pluripotent stem cells promise the solution to current challenges in basic and biomedical research. Further progress and widespread applications are however limited by long developmental time, variable success, and lack of direct comparison to an in vivo reference. To overcome those limitations, we derived organoids from rapidly developing teleosts. We demonstrate how primary embryonic stem cells from zebrafish and medaka efficiently self-organize into anterior neural structures, particularly retina. Within four days, blastula-stage cell aggregates reproducibly execute key steps of eye development: retinal specification, morphogenesis and differentiation. The number of aggregated cells as well as genetic factors crucially impacted upon the concomitant morphological changes that were intriguingly reflecting the in vivo situation. High reproducibility and rapid development of fish-derived organoids in combination with advanced genome editing techniques immediately allow addressing aspects of development and disease, and systematically probing the impact of the physical environment on morphogenesis and differentiation.

Effects of Self-Assembling Peptide RADA16-І Hydrogel on Neural Differentiation of Bone Marrow Mesenchymal Stem Cells

2014 ◽  
Vol 998-999 ◽  
pp. 238-242 ◽  
Author(s):  
Yan Sheng Liao ◽  
Li Deng ◽  
Xiao Qing Gao ◽  
Chao Xian Yang
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Neural Differentiation ◽  
Fluorescent Protein ◽  
Morphological Changes ◽  
Control Group ◽  
Induction Medium ◽  
Self Assembling ◽  
Marrow Mesenchymal Stem Cells

Objective: To establish composite culture system of rat bone marrow mesenchymal stem cells (BMSCs) and self-assembling peptide hydrogel RADA16-І, and to investigate the effect of RADA16-І hydrogel on neural differentiation of BMSCs. Methods: BMSCs were isolated, cultivated and labeled with green fluorescent protein (GFP), then they were inoculated on glass coverslips or in RADA16-І solution to form control group and RADA16-І group respectively. The morphological changes of BMSCs induced by neural induction medium were observed, and GFAP, NeuN and Map-2 expressions of BMSCs in each group were detected with immunofluorescence. Results: The induced BMSCs presented neuron-like change, and the rates of GFAP and NF-200 positive cells in RADA16-І group were higher than that in control group (P < 0.05). Conclusion: Self-assembling peptide RADA16-І hydrogel can promote neural differentiation of BMSCs, and which may be used as scaffold material on BMSCs transplantation for treatment of nervous system diseases.

scholarly journals Self-Assembling Scaffolds Supported Long-Term Growth of Human Primed Embryonic Stem Cells and Upregulated Core and Naïve Pluripotent Markers

Cells ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1650 ◽  
Author(s):  
Christina McKee ◽  
Christina Brown ◽  
G. Rasul Chaudhry
Keyword(s):  
Stem Cells ◽  
Embryonic Stem Cells ◽  
Three Dimensional ◽  
Embryonic Stem ◽  
Extended Period ◽  
Culture Conditions ◽  
Differentiation Potential ◽  
Self Assembling

The maintenance and expansion of human embryonic stem cells (ESCs) in two-dimensional (2-D) culture is technically challenging, requiring routine manipulation and passaging. We developed three-dimensional (3-D) scaffolds to mimic the in vivo microenvironment for stem cell proliferation. The scaffolds were made of two 8-arm polyethylene glycol (PEG) polymers functionalized with thiol (PEG-8-SH) and acrylate (PEG-8-Acr) end groups, which self-assembled via a Michael addition reaction. When primed ESCs (H9 cells) were mixed with PEG polymers, they were encapsulated and grew for an extended period, while maintaining their viability, self-renewal, and differentiation potential both in vitro and in vivo. Three-dimensional (3-D) self-assembling scaffold-grown cells displayed an upregulation of core pluripotency genes, OCT4, NANOG, and SOX2. In addition, the expression of primed markers decreased, while the expression of naïve markers substantially increased. Interestingly, the expression of mechanosensitive genes, YAP and TAZ, was also upregulated. YAP inhibition by Verteporfin abrogated the increased expression of YAP/TAZ as well as core and naïve pluripotent markers. Evidently, the 3-D culture conditions induced the upregulation of makers associated with a naïve state of pluripotency in the primed cells. Overall, our 3-D culture system supported the expansion of a homogenous population of ESCs and should be helpful in advancing their use for cell therapy and regenerative medicine.

Reporter System Controlled by the Involucrin Promoter as a Tool to Follow the Epidermal Differentiation

2021 ◽  
Author(s):  
Myrian Thiago Pruschinski Fernandes ◽  
Jeniffer Farias dos Santos ◽  
Bruna Letícia Freitas ◽  
Gustavo Roncoli Reigado ◽  
Fernanda Antunes ◽  
...  
Keyword(s):  
Stem Cells ◽  
Lentiviral Vector ◽  
Morphological Changes ◽  
Epidermal Differentiation ◽  
Reporter System ◽  
Specific Expression ◽  
Simple Strategy ◽  
Skin Biology ◽  
Msc Differentiation

Abstract Different approaches have been explored to study skin biology, including the use of stem cells. Mesenchymal stem cells (MSC) from umbilical cord can be safely and easily obtained, however a simple strategy to monitor their differentiation is essential. Involucrin is a marker of keratinocyte terminal differentiation, and its promoter (pINV) directs stratum-specific expression of this protein. We designed a reporter system containing EGFP under control of pINV to assess MSC differentiation into keratinocytes. The functional sequence of pINV was inserted into a lentiviral vector, originating LeGO-GpINV. MSC were transduced with the LeGO-GpINV and induced to differentiate into keratinocytes upon cultivation with Keratinocyte Serum Free Medium supplemented. MSC differentiation was confirmed by morphological changes and by the expression of epidermal markers, by flow cytometry, quantitative PCR and western blot. The activity of kallikreins 5, 6 and 7 was detected using fluorogenic substrates. After 14 days of differentiation, MSC transduced with LeGO-GpINV showed an increase in EGFP fluorescence and expressed CK10, CK14, involucrin and filaggrin. There was also an increase in the kallikrein activity. This reporter system allowed to temporally assess the epidermal differentiation, simultaneously with involucrin expression, opening perspectives for the in vivo study of skin biology and in regenerative medicine.

Abstract 469: Thymosin Beta4 Enhancing Therapeutic Efficacy of Human Adipose-derived Stem Cells in Mouse Ischemic Hindlimb Model

2020 ◽  
Vol 127 (Suppl_1) ◽  
Author(s):  
Jong-ho Kim ◽  
Hyung Joon Joo ◽  
Soon Jun Hong
Keyword(s):  
Stem Cells ◽  
Intracellular Signaling ◽  
Morphological Changes ◽  
Additional Treatment ◽  
Endothelial Differentiation ◽  
Adipose Derived Stem Cells ◽  
Differentiation Potential ◽  
Beneficial Effects ◽  
Thymosin Beta4

Thymosin Beta4 (Tβ4) is a G-actin sequestering protein that contributes to diverse cellular activities, such as migration and angiogenesis. In this study, the beneficial effects of combined cell therapy with Tβ4 and human adipose-derived stem cells (hASCs) in a mouse ischemic hindlimb model were investigated. We observed that exogenous treatment with Tβ4 enhanced endogenous TMSB4X mRNA expression and promoted morphological changes (increased cell length) in hASCs. Interestingly, Tβ4 induced the active state of hASCs by up-regulating intracellular signaling pathways including the PI3K/AKT/mTOR and MAPK/ERK pathways. Treatment with Tβ4 significantly increased cell migration and sprouting from microbeads. Moreover, additional treatment with Tβ4 promoted the endothelial differentiation potential of hASCs by up-regulating various angiogenic genes. To evaluate the in vivo effects of the Tβ4-hASCs combination on vessel recruitment, dorsal window chambers were transplanted, and the co-treated mice were found to have a significantly increased number of microvessel branches. Transplantation of hASCs in combination with Tβ4 was found to improve blood flow and attenuate limb or foot loss post-ischemia compared to transplantation with hASCs alone. Taken together, the therapeutic application of hASCs combined with Tβ4 could be effective in enhancing endothelial differentiation and vascularization for treating hindlimb ischemia.

Ultrastructural Study of a differentiating human colon carcinoma cell line

1990 ◽  
Vol 48 (3) ◽  
pp. 208-209
Author(s):  
Sylvie Polak-Charcon ◽  
Mehrdad Hekmati ◽  
Yehuda Ben Shaul
Keyword(s):  
Cell Line ◽  
Morphological Changes ◽  
Secretory Granules ◽  
Human Colon ◽  
Cell Types ◽  
Culture Conditions ◽  
Morphological Evidence ◽  
Human Colon Carcinoma Cell ◽  
Colon Cell

The epithelium of normal human colon mucosa “in vivo” exhibits a gradual pattern of differentiation as undifferentiated stem cells from the base of the crypt of “lieberkuhn” rapidly divide, differentiate and migrate toward the free surface. The major differentiated cell type of the intestine observed are: absorptive cells displaying brush border, goblet cells containing mucous granules, Paneth and endocrine cells containing dense secretory granules. These different cell types are also found in the intestine of the 13-14 week old embryo.We present here morphological evidence showing that HT29, an adenocarcinoma of the human colon cell line, can differentiate into various cell types by changing the growth and culture conditions and mimic morphological changes found during development of the intestine in the human embryo.HT29 cells grown in tissue-culture dishes in DMEM and 10% FCS form at late confluence a multilayer of morphologically undifferentiated cell culture covered with irregular microvilli, and devoid of tight junctions (Figs 1-3).

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