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1.
Cell Mol Life Sci ; 81(1): 128, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472451

RESUMO

Epigenetic dysregulation that leads to alterations in gene expression and is suggested to be one of the key pathophysiological factors of Parkinson's disease (PD). Here, we found that α-synuclein preformed fibrils (PFFs) induced histone H3 dimethylation at lysine 9 (H3K9me2) and increased the euchromatic histone methyltransferases EHMT1 and EHMT2, which were accompanied by neuronal synaptic damage, including loss of synapses and diminished expression levels of synaptic-related proteins. Furthermore, the levels of H3K9me2 at promoters in genes that encode the synaptic-related proteins SNAP25, PSD95, Synapsin 1 and vGLUT1 were increased in primary neurons after PFF treatment, which suggests a linkage between H3K9 dimethylation and synaptic dysfunction. Inhibition of EHMT1/2 with the specific inhibitor A-366 or shRNA suppressed histone methylation and alleviated synaptic damage in primary neurons that were treated with PFFs. In addition, the synaptic damage and motor impairment in mice that were injected with PFFs were repressed by treatment with the EHMT1/2 inhibitor A-366. Thus, our findings reveal the role of histone H3 modification by EHMT1/2 in synaptic damage and motor impairment in a PFF animal model, suggesting the involvement of epigenetic dysregulation in PD pathogenesis.


Assuntos
Transtornos Motores , Doença de Parkinson , Animais , Camundongos , Histonas/metabolismo , Metilação , Neurônios/metabolismo , alfa-Sinucleína/metabolismo
2.
Int J Mol Sci ; 25(2)2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38256154

RESUMO

Three-dimensional (3D) hepatocyte models have become a research hotspot for evaluating drug metabolism and hepatotoxicity. Compared to two-dimensional (2D) cultures, 3D cultures are better at mimicking the morphology and microenvironment of hepatocytes in vivo. However, commonly used 3D culture techniques are not suitable for high-throughput drug screening (HTS) due to their high cost, complex handling, and inability to simulate cell-extracellular matrix (ECM) interactions. This article describes a method for rapid and reproducible 3D cell cultures with ECM-cell interactions based on 3D culture instrumentation to provide more efficient HTS. We developed a microsphere preparation based on a high-voltage electrostatic (HVE) field and used sodium alginate- and collagen-based hydrogels as scaffolds for 3D cultures of HepG2 cells. The microsphere-generating device enables the rapid and reproducible preparation of bioactive hydrogel microspheres. This 3D culture system exhibited better cell viability, heterogeneity, and drug-metabolizing activity than 2D and other 3D culture models, and the long-term culture characteristics of this system make it suitable for predicting long-term liver toxicity. This system improves the overall applicability of HepG2 spheroids in safety assessment studies, and this simple and controllable high-throughput-compatible method shows potential for use in drug toxicity screening assays and mechanistic studies.


Assuntos
Hidrogéis , Fígado , Humanos , Microesferas , Células Hep G2 , Hidrogéis/farmacologia , Eletricidade Estática
3.
Cell Prolif ; 57(3): e13554, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37767639

RESUMO

'General requirements for the production of extracellular vesicles derived from human stem cells' is the first guideline for stem cells derived extracellular vesicles in China, jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research. This standard specifies the general requirements, process requirements, packaging and labelling requirements and storage requirements for preparing extracellular vesicles derived from human stem cells, which is applicable to the research and production of extracellular vesicles derived from stem cells. It was originally released by the China Society for Cell Biology on 30 August 2022. We hope that the publication of this guideline will promote institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardisation of extracellular vesicles derived from human stem cells.


Assuntos
Vesículas Extracelulares , Células-Tronco , Humanos , China
4.
J Immunother Cancer ; 11(12)2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38056897

RESUMO

BACKGROUND: Lack of tumor-infiltrating T lymphocytes and concurrent T-cell dysfunction have been identified as major contributors to glioblastoma (GBM) immunotherapy resistance. Upregulating CXCL10 in the tumor microenvironment (TME) is a promising immunotherapeutic approach that potentially increases tumor-infiltrating T cells and boosts T-cell activity but is lacking effective delivery methods. METHODS: In this study, mesenchymal stem cells (MSCs) were transduced with a recombinant lentivirus encoding Cxcl10, Nrf2 (an anti-apoptosis gene), and a ferritin heavy chain (Fth) reporter gene in order to increase their CXCL10 secretion, TME survival, and MRI visibility. Using FTH-MRI guidance, these cells were injected into the tumor periphery of orthotopic GL261 and CT2A GBMs in mice. Combination therapy consisting of CXCL10-Nrf2-FTH-MSC transplantation together with immune checkpoint blockade (ICB) was also performed for CT2A GBMs. Thereafter, in vivo and serial MRI, survival analysis, and histology examinations were conducted to assess the treatments' efficacy and mechanism. RESULTS: CXCL10-Nrf2-FTH-MSCs exhibit enhanced T lymphocyte recruitment, oxidative stress tolerance, and iron accumulation. Under in vivo FTH-MRI guidance and monitoring, peritumoral transplantation of CXCL10-Nrf2-FTH-MSCs remarkably inhibited orthotopic GL261 and CT2A tumor growth in C57BL6 mice and prolonged animal survival. While ICB alone demonstrated no therapeutic impact, CXCL10-Nrf2-FTH-MSC transplantation combined with ICB demonstrated an enhanced anticancer effect for CT2A GBMs compared with transplanting it alone. Histology revealed that peritumorally injected CXCL10-Nrf2-FTH-MSCs survived longer in the TME, increased CXCL10 production, and ultimately remodeled the TME by increasing CD8+ T cells, interferon-γ+ cytotoxic T lymphocytes (CTLs), GzmB+ CTLs, and Th1 cells while reducing regulatory T cells (Tregs), exhausted CD8+ and exhausted CD4+ T cells. CONCLUSIONS: MRI-guided peritumoral administration of CXCL10 and Nrf2-overexpressed MSCs can significantly limit GBM growth by revitalizing T lymphocytes within TME. The combination application of CXCL10-Nrf2-FTH-MSC transplantation and ICB therapy presents a potentially effective approach to treating GBM.


Assuntos
Glioblastoma , Células-Tronco Mesenquimais , Animais , Camundongos , Linfócitos T CD8-Positivos , Glioblastoma/terapia , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2 , Microambiente Tumoral
5.
Int J Mol Sci ; 24(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37446226

RESUMO

The remarkable advancements related to cerebral organoids have provided unprecedented opportunities to model human brain development and diseases. However, despite their potential significance in neurodegenerative diseases such as Parkinson's disease (PD), the role of exosomes from cerebral organoids (OExo) has been largely unknown. In this study, we compared the effects of OExo to those of mesenchymal stem cell (MSC)-derived exosomes (CExo) and found that OExo shared similar neuroprotective effects to CExo. Our findings showed that OExo mitigated H2O2-induced oxidative stress and apoptosis in rat midbrain astrocytes by reducing excess ROS production, antioxidant depletion, lipid peroxidation, mitochondrial dysfunction, and the expression of pro-apoptotic genes. Notably, OExo demonstrated superiority over CExo in promoting the differentiation of human-induced pluripotent stem cells (iPSCs) into dopaminergic (DA) neurons. This was attributed to the higher abundance of neurotrophic factors, including neurotrophin-4 (NT-4) and glial-cell-derived neurotrophic factor (GDNF), in OExo, which facilitated the iPSCs' differentiation into DA neurons in an LIM homeobox transcription factor 1 alpha (LMX1A)-dependent manner. Our study provides novel insight into the biological properties of cerebral organoids and highlights the potential of OExo in the treatment of neurodegenerative diseases such as PD.


Assuntos
Exossomos , Doença de Parkinson , Ratos , Humanos , Animais , Exossomos/metabolismo , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , Diferenciação Celular/genética , Doença de Parkinson/terapia , Doença de Parkinson/metabolismo , Neurônios Dopaminérgicos/metabolismo , Organoides/metabolismo , Estresse Oxidativo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas com Homeodomínio LIM/metabolismo
6.
Cell Reprogram ; 25(5): 212-223, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37366790

RESUMO

Studying human somatic cell-to-neuron conversion using primary brain-derived cells as starting cell source is hampered by limitations and variations in human biopsy material. Thus, delineating the molecular variables that allow changing the identity of somatic cells, permit adoption of neuronal phenotypes, and foster maturation of induced neurons (iNs) is challenging. Based on our previous results that pericytes derived from the adult human cerebral cortex can be directly converted into iNs (Karow et al., 2018; Karow et al., 2012), we here introduce human induced pluripotent stem cell (hiPSC)-derived pericytes (hiPSC-pericytes) as a versatile and more uniform tool to study the pericyte-to-neuron conversion process. This strategy enables us to derive scalable cell numbers and allows for engineering of the starting cell population such as introducing reporter tools before differentiation into hiPSC-pericytes and subsequent iN conversion. Harvesting the potential of this approach, we established hiPSC-derived human-human neuronal cocultures that not only allow for independent manipulation of each coculture partner but also resulted in morphologically more mature iNs. In summary, we exploit hiPSC-based methods to facilitate the analysis of human somatic cell-to-neuron conversion.


Assuntos
Células-Tronco Pluripotentes Induzidas , Adulto , Humanos , Reprogramação Celular , Pericitos/fisiologia , Neurônios , Diferenciação Celular/fisiologia
7.
ISA Trans ; 139: 436-447, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37164877

RESUMO

In order to improve the performance of a permanent magnet synchronous motor (PMSM) speed controller, an advanced reaching law sliding mode control (ASMC) strategy is proposed in this study. The advanced sliding mode reaching law (ASMRL) introduces a power term of the system state and a checkmark function term about the sliding mode function based on the traditional constant-proportional rate reaching law(TSMRL) , and replaces the sign function with a hyperbolic tangent function. A detailed theoretical analysis of the characteristics of the ASMRL is then presented. The theoretical analysis shows that the ASMRL converges to the sliding mode surface more quickly and with less chattering than the TSMRL. In addition, a sliding mode disturbance observer (SMDO) is designed to estimate the total disturbance of the system, and the estimated disturbance is compensated to ASMC. Then the stability of the system with ASMC and the stability of the system with ASMC+SMDO is proved by Lyapunov's theorem. Finally, the proposed control strategy is validated on an experimental platform of PMSM. The experimental results show that the ASMC has a faster convergence speed, smaller chattering, better disturbance rejection performance than the traditional constant-proportional rate reaching law sliding mode control(TSMC), and better performance with the addition of SMDO.

8.
Cell Transplant ; 32: 9636897231156215, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36840468

RESUMO

Healing of full-thickness skin wounds remains a major challenge. Recently, human umbilical cord mesenchymal stem cells (hUC-MSCs) were shown to possess an extraordinary potential to promote skin repair in clinical settings. However, their low survival rate after transplantation limits their therapeutic efficiency in treating full-thickness skin wounds. Hydrogels are considered an ideal cell transplantation vector owing to their three-dimensional mesh structure, good biosafety, and biodegradation. The objective of this study was to investigate the skin wound healing effect of a fibrin hydrogel scaffold loaded with hUC-MSCs. We found that the fibrin hydrogel had a three-dimensional mesh structure and low cytotoxicity and could prolong the time of cell survival in the peri-wound area. The number of green fluorescent protein (GFP)-labeled hUC-MSCs was higher in the full-thickness skin wound of mice treated with hydrogel-hUC-MSCs than those of mice treated with cell monotherapy. In addition, the combination therapy between the hydrogel and hUC-MSCs speed up wound closure, its wound healing rate was significantly higher than those of phosphate-buffered saline (PBS) therapy, hydrogel monotherapy, and hUC-MSCs monotherapy. Furthermore, the results showed that the combination therapy between hydrogel and hUC-MSCs increased keratin 10 and keratin 14 immunofluorescence staining, and upregulated the relative gene expressions of epidermal growth factor (EGF), transforming growth factor-ß1 (TGF-ß1), and vascular endothelial growth factor A (VEGFA), promoting epithelial regeneration and angiogenesis. In conclusion, the fibrin hydrogel scaffold provides a relatively stable sterile environment for cell adhesion, proliferation, and migration, and prolongs cell survival at the wound site. The hydrogel-hUC-MSCs combination therapy promotes wound closure, re-epithelialization, and neovascularization. It exhibits a remarkable therapeutic effect, being more effective than the monotherapy with hUC-MSCs or hydrogel.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Cicatrização , Animais , Humanos , Camundongos , Hidrogéis , Transplante de Células-Tronco Mesenquimais/métodos , Cordão Umbilical/citologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Alicerces Teciduais
9.
Metabolism ; 140: 155398, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36627079

RESUMO

INTRODUCTION: Cell therapy with mesenchymal stem cells (MSCs) and biomaterials holds great potential for the treatment of diabetic ulceration; however, the underlying mechanism as well as its compatibility with the first-line anti-diabetic drug, metformin (MTF), has not been well elucidated. METHODS: MSCs derived from the umbilical cord were labeled with fluorescent proteins, followed by transplantation in a fibrin scaffold (MSCs/FG) onto the STZ-induced diabetic wound in a C57BL6/J mouse model. MTF was administered by oral gavage at a dose of 250 mg/kg/day. The wound healing rate, epithelization, angiogenesis, and underlying mechanism were evaluated in MSCs/FG- and MTF-treated diabetic wounds. Moreover, the dose-dependent effects of MTF and involvement of the Akt/mTOR pathway were analyzed in keratinocyte and fibroblast cultures. RESULTS: MSCs/FG significantly promoted angiogenesis in diabetic wound healing without signs of differentiation or integration. The recruitment of fibroblasts and keratinocytes by MSCs/FG promotes migration and vascular endothelial growth factor (VEGF) expression in an Akt/mTOR-dependent manner. MTF, which is generally considered a mTOR inhibitor, displayed dose-dependent effects on MSC-unregulated Akt/mTOR and VEGF expression. Oral administration of MTF at an anti-diabetic dosage synergistically acted with MSCs/FG to promote Akt/mTOR activation, VEGF expression, and subsequent angiogenesis in diabetic wounds; however, it reduced the survival of MSCs. CONCLUSIONS: Our study identifies that MTF coordinates with mesenchymal cells to promote Akt/mTOR activation and VEGF-mediated angiogenesis during diabetic wound healing. These findings offer new insights into MSCs engraftment in FG scaffolds for diabetic wound healing and provide support for the promotion of MSCs therapy in patients prescribed with MTF.


Assuntos
Diabetes Mellitus , Células-Tronco Mesenquimais , Metformina , Camundongos , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Metformina/farmacologia , Metformina/uso terapêutico , Cicatrização/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Células-Tronco Mesenquimais/metabolismo , Diabetes Mellitus/metabolismo
10.
Sensors (Basel) ; 22(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36559980

RESUMO

To combine the advantages of linear active disturbance rejection control (LADRC) and nonlinear active disturbance rejection control (NLADRC) and improve the contradiction between the response speed and control precision caused by the limitation of parameter α in NLADRC, a linear-nonlinear switching active disturbance rejection control (SADRC) strategy based on linear-nonlinear switching extended state observer (SESO) and linear-nonlinear switching state error feedback control law (SSEF) is proposed in this paper. First, the reasons for the performance differences between LADRC and NLADRC are analysed from a theoretical point of view, then a linear-nonlinear switching function (SF) that can change the switching point by adjusting its parameters is constructed and then propose SESO and SSEF based on this function. Subsequently, the convergence range of the observation error of the SESO is derived, and the stability of the closed-loop system with the application of SSEF is also demonstrated. Finally, the proposed SADRC control strategy is applied to a 707 W permanent magnet synchronous motor (PMSM) experimental platform, and both the dynamic and static characteristics of SADRC are verified. The experimental results show that the proposed SADRC control strategy can well combine the performance advantages of LADRC and NLADRC and can better balance the response speed and control precision and has a better capacity for disturbance rejection, which has potential application in engineering practise.

11.
Sensors (Basel) ; 22(19)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36236349

RESUMO

Errors in microelectromechanical systems (MEMS) inertial measurement units (IMUs) are large, complex, nonlinear, and time varying. The traditional noise reduction and compensation methods based on traditional models are not applicable. This paper proposes a noise reduction method based on multi-layer combined deep learning for the MEMS gyroscope in the static base state. In this method, the combined model of MEMS gyroscope is constructed by Convolutional Denoising Auto-Encoder (Conv-DAE) and Multi-layer Temporal Convolutional Neural with the Attention Mechanism (MultiTCN-Attention) model. Based on the robust data processing capability of deep learning, the noise features are obtained from the past gyroscope data, and the parameter optimization of the Kalman filter (KF) by the Particle Swarm Optimization algorithm (PSO) significantly improves the filtering and noise reduction accuracy. The experimental results show that, compared with the original data, the noise standard deviation of the filtering effect of the combined model proposed in this paper decreases by 77.81% and 76.44% on the x and y axes, respectively; compared with the existing MEMS gyroscope noise compensation method based on the Autoregressive Moving Average with Kalman filter (ARMA-KF) model, the noise standard deviation of the filtering effect of the combined model proposed in this paper decreases by 44.00% and 46.66% on the x and y axes, respectively, reducing the noise impact by nearly three times.

12.
Sensors (Basel) ; 22(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36236388

RESUMO

A traditional flat-panel spectrometer does not allow high-resolution observation and miniaturization simultaneously. In this study, a compact, high-resolution cross-dispersion spectrometer was designed based on the theoretical basis of echelle grating for recording an infrared spectrum. To meet the high-resolution observation and miniaturization design requirements, a reflective immersion grating was used as the primary spectroscopic device. To compress the beam aperture of the imaging system, the order-separation device of the spectrometer adopted toroidal uniform line grating, which had both imaging and dispersion functions in the spectrometer. The aberration balance condition of the toroidal uniform line grating was analyzed based on the optical path difference function of the concave grating, and dispersion characteristics of the immersed grating and thermal design of the infrared lens were discussed based on the echelle grating. An immersion echelle spectrometer optical system consisting of a culmination system, an immersed echelle grating, and a converged system was used. The spectrometer was based on the asymmetrical Czerny-Turner and Littrow mount designs, and it was equipped with a 320 × 256 pixel detector array. The designed wavelength range was 3.7-4.8 µm, the F-number was 4, and the central wavelength resolution was approximately 30,000. An infrared cooling detector was used. The design results showed that, in the operating band range, the root implied that the square diameter of the spectrometer spot diagram was less than 30 µm, the energy was concentrated in a pixel size range, and the spectrometer system design met the requirements.

13.
ACS Appl Mater Interfaces ; 13(48): 56825-56837, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34825820

RESUMO

Because of the blood-brain barrier and the high infiltration of glioma cells, the diagnostic accuracy and treatment efficiency of gliomas are still facing challenges. There is an urgent need to explore the integration of diagnostic and therapeutic methods to achieve an accurate diagnosis, guide surgery, and inhibit postoperative recurrence. In this work, we developed a macrophage loaded with a photothermal nanoprobe (MFe3O4-Cy5.5), which is able to cross the blood-brain barrier and accumulate into deep gliomas to achieve multimodal imaging and guided glioma surgery purposes. With desirable probing depth and high signal-to-noise ratio, Fe3O4-Cy5.5 can perform fluorescence, photoacoustic, and magnetic resonance imaging, which can distinguish brain tumors from the surrounding normal tissues and accurately guide glioma resection. Meanwhile, Fe3O4-Cy5.5 can effectively induce local photothermal therapy and inhibit the recurrence of glioma after surgery. These results demonstrate that the macrophage-mediated Fe3O4-Cy5.5, which can achieve a multimodal diagnosis, accurate imaging-guided surgery, and effective photothermal therapy, is a promising nanoplatform for gliomas.


Assuntos
Materiais Biomiméticos/farmacologia , Neoplasias Encefálicas/terapia , Carbocianinas/farmacologia , Glioma/terapia , Nanopartículas de Magnetita/química , Terapia Fototérmica , Animais , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/diagnóstico por imagem , Carbocianinas/química , Glioma/diagnóstico por imagem , Humanos , Macrófagos/efeitos dos fármacos , Masculino , Teste de Materiais , Imagem Multimodal , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/terapia , Tamanho da Partícula , Porosidade , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas
14.
Int J Mol Sci ; 22(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34830023

RESUMO

Transplantation of exogenous dopaminergic (DA) neurons is an alternative strategy to replenish DA neurons that have lost along the course of Parkinson's disease (PD). From the perspective of ethical acceptation, the source limitations, and the intrinsic features of PD pathology, astrocytes (AS) and mesenchymal stem cells (MSCs) are the two promising candidates of DA induction. In the present study, we induced AS or MSCs primary culture by the combination of the classical transcription-factor cocktails Mash1, Lmx1a, and Nurr1 (MLN), the chemical cocktails (S/C/D), and the morphogens SHH, FGF8, and FGF2 (S/F8/F2); the efficiency of induction into DA neurons was further analyzed by using immunostaining against the DA neuronal markers. AS could be efficiently converted into the DA neurons in vitro by the transcriptional regulation of MLN, and the combination with S/C/D or S/F8/F2 further increased the conversion efficiency. In contrast, MSCs from umbilical cord (UC-MSCs) or adipose tissue (AD-MSCs) showed moderate TH immunoreactivity after the induction with S/F8/F2 instead of with MLN or S/C/D. Our data demonstrated that AS and MSCs held lineage-specific molecular codes on the induction into DA neurons and highlighted the unique superiority of AS in the potential of cell replacement therapy for PD.


Assuntos
Astrócitos/transplante , Neurônios Dopaminérgicos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Doença de Parkinson/terapia , Animais , Astrócitos/metabolismo , Diferenciação Celular/genética , Dopamina/metabolismo , Neurônios Dopaminérgicos/patologia , Neurônios Dopaminérgicos/transplante , Humanos , Transplante de Células-Tronco Mesenquimais , Doença de Parkinson/genética , Doença de Parkinson/patologia , Cultura Primária de Células , Ratos , Fatores de Transcrição/genética , Cordão Umbilical/metabolismo , Cordão Umbilical/transplante
15.
Nanoscale Res Lett ; 16(1): 107, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34128153

RESUMO

Parkinson's disease (PD) is characterized by the progressive loss of dopaminergic neurons in the midbrain, and the stem cell transplantation method provides a promising strategy for the treatment. In these studies, tracking the biological behaviors of the transplanted cells in vivo is essential for a basic understanding of stem cell function and evaluation of clinical effectiveness. In the present study, we developed a novel ultrasmall superparamagnetic iron oxide nanoparticles coating with the polyacrylic acid (PAA) and methoxypolyethylene glycol amine (PEG) by thermal decomposition method and a two-step modification. The USPIO-PAA/PEG NPs have a uniform diameter of 10.07 ± 0.55 nm and proper absorption peak of the corresponding ligands, as showed by TEM and FTIR. MTT showed that the survival of cells incubated with USPIO-PAA/PEG NPs remained above 96%. The synthesized USPIO-PAA/PEG had a good relaxation rate of 84.65 s-1 Mm-1, indicating that they could be efficiently uptake and traced by MRI. Furthermore, the primary human adipose-derived stem cells (HADSCs) were characterized, labeled with USPIO-PAA/PEG and transplanted into the striatum of 6-hydroxydopamine (6-OHDA)-induced PD rat models. The labeled cells could be traced by MRI for up to 3 weeks after the transplantation surgery; moreover, transplantation with the labeled HADSCs significantly attenuated apomorphine-induced rotations in PD models and increased the number of the dopaminergic neurons in the substania nigra. Overall, the development of USPIO-PAA/PEG NPs provides a promising tool for in vivo tracing technique of cell therapy and identifies a novel strategy to track stem cells with therapeutic potential in PD.

16.
Stem Cells Dev ; 30(15): 782-796, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34030464

RESUMO

In women of reproductive age, severe injuries to the ovary are often accompanied by premature ovarian failure (POF), which can result in amenorrhea or infertility. Hormone replacement therapy has been used to treat POF; however, it has limited therapeutic efficiency and may cause several side effects. In this study, we aimed to fabricate a Matrigel scaffold loaded with human umbilical cord-derived mesenchymal stem cells (MSCs) and explore its potential to restore ovarian function and repair ovarian structures in vitro and in vivo. POF mouse models were established by injecting mice with cyclophosphamide for 15 consecutive days. Then, MSC/Matrigel was transplanted into the ovaries of the mice. Five weeks later, the morphology of the ovaries and follicles was observed by hematoxylin/eosin staining, and the tissue fibrosis ratio was measured using Masson's trichrome staining. The number of blood vessels was evaluated by α-smooth muscle actin and CD31 immunofluorescence, and Ki67 expression was used to determine the proliferation of granulosa cells. The expression of vascular endothelial growth factor (VEGF)-A was assessed by western blotting. The Matrigel scaffold regulated the expression of VEGF-A in vitro. Moreover, it promoted MSC survival and proliferation and prevented MSC apoptosis in vivo. After the transplantation of the MSC/Matrigel, the number of follicles was significantly increased in the mice with POF, and the tissue fibrosis ratio was reduced. Furthermore, the MSC/Matrigel significantly improved the proliferation rate of granulosa cells, increased the number of blood vessels, and upregulated the expression of VEGF-A. These findings demonstrate that MSC/Matrigel may support follicular development and help restore ovarian structures in vivo.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Insuficiência Ovariana Primária , Animais , Proliferação de Células , Colágeno , Combinação de Medicamentos , Feminino , Células da Granulosa/metabolismo , Humanos , Laminina , Camundongos , Insuficiência Ovariana Primária/metabolismo , Insuficiência Ovariana Primária/terapia , Proteoglicanas , Cordão Umbilical , Fator A de Crescimento do Endotélio Vascular/metabolismo
17.
Contrast Media Mol Imaging ; 2020: 8843084, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33299387

RESUMO

Previous studies using contrast-enhanced imaging for glioma isocitrate dehydrogenase (IDH) mutation assessment showed promising yet inconsistent results, and this study attempts to explore this problem by using an advanced tracer kinetic model, the distributed parameter model (DP). Fifty-five patients with glioma examined using dynamic contrast-enhanced imaging sequence at a 3.0 T scanner were retrospectively reviewed. The imaging data were processed using DP, yielding the following parameters: blood flow F, permeability-surface area product PS, fractional volume of interstitial space Ve, fractional volume of intravascular space Vp, and extraction ratio E. The results were compared with the Tofts model. The Wilcoxon test and boxplot were utilized for assessment of differences of model parameters between IDH-mutant and IDH-wildtype gliomas. Spearman correlation r was employed to investigate the relationship between DP and Tofts parameters. Diagnostic performance was evaluated using receiver operating characteristic (ROC) curve analysis and quantified using the area under the ROC curve (AUC). Results showed that IDH-mutant gliomas were significantly lower in F (P = 0.018), PS (P < 0.001), Vp (P < 0.001), E (P < 0.001), and Ve (P = 0.002) than IDH-wildtype gliomas. In differentiating IDH-mutant and IDH-wildtype gliomas, Vp had the best performance (AUC = 0.92), and the AUCs of PS and E were 0.82 and 0.80, respectively. In comparison, Tofts parameters were lower in K trans (P = 0.013) and Ve (P < 0.001) for IDH-mutant gliomas. No significant difference was observed in Kep (P = 0.525). The AUCs of K trans, Ve, and Kep were 0.69, 0.79, and 0.55, respectively. Tofts-derived Ve showed a strong correlation with DP-derived Ve (r > 0.9, P < 0.001). K trans showed a weak correlation with F (r < 0.3, P > 0.16) and a very weak correlation with PS (r < 0.06, P > 0.8), both of which were not statistically significant. The findings by DP revealed a tissue environment with lower vascularity, lower vessel permeability, and lower blood flow in IDH-mutant than in IDH-wildtype gliomas, being hostile to cellular differentiation of oncogenic effects in IDH-mutated gliomas, which might help to explain the better outcomes in IDH-mutated glioma patients than in glioma patients of IDH-wildtype. The advantage of DP over Tofts in glioma DCE data analysis was demonstrated in terms of clearer elucidation of tissue microenvironment and better performance in IDH mutation assessment.


Assuntos
Neoplasias Encefálicas/patologia , Meios de Contraste/análise , Glioma/patologia , Isocitrato Desidrogenase/genética , Mutação , Adulto , Idoso , Neoplasias Encefálicas/genética , Feminino , Seguimentos , Glioma/genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Estudos Retrospectivos
18.
EMBO J ; 39(21): e104472, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32929771

RESUMO

In adult hippocampal neurogenesis, stem/progenitor cells generate dentate granule neurons that contribute to hippocampal plasticity. The establishment of a morphologically defined dendritic arbor is central to the functional integration of adult-born neurons. We investigated the role of canonical Wnt/ß-catenin signaling in dendritogenesis of adult-born neurons. We show that canonical Wnt signaling follows a biphasic pattern, with high activity in stem/progenitor cells, attenuation in immature neurons, and reactivation during maturation, and demonstrate that this activity pattern is required for proper dendrite development. Increasing ß-catenin signaling in maturing neurons of young adult mice transiently accelerated dendritic growth, but eventually produced dendritic defects and excessive spine numbers. In middle-aged mice, in which protracted dendrite and spine development were paralleled by lower canonical Wnt signaling activity, enhancement of ß-catenin signaling restored dendritic growth and spine formation to levels observed in young adult animals. Our data indicate that precise timing and strength of ß-catenin signaling are essential for the correct functional integration of adult-born neurons and suggest Wnt/ß-catenin signaling as a pathway to ameliorate deficits in adult neurogenesis during aging.


Assuntos
Hipocampo/metabolismo , Neurônios/metabolismo , Transdução de Sinais/fisiologia , beta Catenina/metabolismo , Envelhecimento/metabolismo , Animais , Proteína Axina/genética , Feminino , Hipocampo/crescimento & desenvolvimento , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Via de Sinalização Wnt , beta Catenina/genética
19.
Cell Prolif ; 53(8): e12858, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32592435

RESUMO

OBJECTIVES: Traditional cancer therapy and regular immunotherapy are ineffective for treating triple-negative breast cancer (TNBC) patients. Recently, chimeric antigen receptor-engineered natural killer cells (CAR NK) have been applied to target several hormone receptors on different cancer cells to improve the efficacy of immunotherapy. Furthermore, epidermal growth factor receptor (EGFR) is a potential therapeutic target for TNBC. Here, we demonstrated that EGFR-specific CAR NK cells (EGFR-CAR NK cells) could be potentially used to treat patients with TNBC exhibiting enhanced EGFR expression. MATERIALS AND METHODS: We investigated the cytotoxic effects of EGFR-CAR NK cells against TNBC cells in vitro and in vivo. The two types of EGFR-CAR NK cells were generated by transducing lentiviral vectors containing DNA sequences encoding the single-chain variable fragment (scFv) regions of the two anti-EGFR antibodies. The cytotoxic and anti-tumor effects of the two cell types were examined by performing cytokine release and cytotoxicity assays in vitro, and tumor growth assays in breast cancer cell line-derived xenograft (CLDX) and patient-derived xenograft (PDX) mouse models. RESULTS: Both EGFR-CAR NK cell types were activated by TNBC cells exhibiting upregulated EGFR expression and specifically triggered the lysis of the TNBC cells in vitro. Furthermore, the two EGFR-CAR NK cell types inhibited CLDX and PDX tumors in mice. CONCLUSIONS: This study suggested that treatment with EGFR-CAR NK cells could be a promising strategy for TNBC patients.


Assuntos
Antineoplásicos/farmacologia , Receptores ErbB/metabolismo , Células Matadoras Naturais/imunologia , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/imunologia , Humanos , Camundongos , Receptores de Antígenos Quiméricos/imunologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
20.
Biochem Biophys Res Commun ; 527(1): 311-316, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32446386

RESUMO

Brain-derived neurotrophic factor (BDNF), which regulates the neuronal survival, differentiation and synaptic plasticity, has been proved to play a critical role in the pathology and treatment of several psychiatric disorders including depression. Dexamethaone (DEX) is indicated for a number of conditions in perinatal medicine, however, the long-term impact of early-life DEX exposure on BDNF expression in hippocampus remains unknown. Here we found that neonatal DEX(ND) exposure leads to insignificant change of BDNF expression levels in the adulthood, albeit increased hyperanxious and depressive-like behaviors. However, the bdnf mRNA and BDNF protein levels were significantly reduced in all the hippocampal subregions during the developmental stages, including the perinatal period and puberty. We conclude that early life DEX exposure leads to a persistent disturbance of BDNF signaling during the developmental stages, which might be associated with the life-long impairment of hippocampal function.


Assuntos
Ansiedade/induzido quimicamente , Fator Neurotrófico Derivado do Encéfalo/antagonistas & inibidores , Depressão/induzido quimicamente , Dexametasona/farmacologia , Hipocampo/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Dexametasona/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Comportamento Exploratório/efeitos dos fármacos , Hipocampo/crescimento & desenvolvimento , Hipocampo/metabolismo , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Relação Estrutura-Atividade
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