A Novel In Vitro Simulator to Investigate Promotion of Reconstruction of Damaged Neuronal Cell Colony Differentiated from iPS Cells with the Aid of Micro Dynamic Stimulation

Neuronal cells are equipped with the function of a sensor that senses stimulation and elongates neurites to connect nearby neuronal cells in forming a neuronal network, as they are generally said to be hard to recover from physical damage, such as in the case of a spinal cord injury. Therefore, in this study, a novel in vitro simulator in which micro dynamic stimulations are applied to a damaged neuronal cell colony artificially is proposed to investigate the possibility of promoting the reconstruction of damaged neuronal cells on a colony basis. A neuronal cell colony differentiated from iPS cells is physically damaged by cutting off treatment, and micro dynamic stimulations are applied to the colony by utilizing a developed mini-vibration table system. NeuroFluor NeuO is used to establish a method for fluorescent staining of the living neuronal cells, and morphologies of the reconstructing neurons are analysed, revealing a relationship between the stimulation and the reconstructing process of the damaged neurons. It is found that significant differences are observed in the reconstructing efficiency between the statically cultured damaged neuronal cell colony and the dynamically stimulated one. The results suggest that applying appropriate micro dynamic stimulations is a promising approach to promote the reconstruction of a damaged neuronal cell colony.

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Circ-Ctnnb1 regulates neuronal injury in spinal cord injury through Wnt/β-catenin signaling pathway

Developmental Neuroscience ◽

10.1159/000521172 ◽

2021 ◽

Author(s):

Jialong Qi ◽

Tao Wang ◽

Zhidong Zhang ◽

Zongsheng Yin ◽

Yiming Liu ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Signaling Pathway ◽

Rat Model ◽

Cell Model ◽

Neuronal Cells ◽

Neuronal Cell ◽

Cord Injury

Study design: Spinal cord injury (SCI) rat model and cell model were established for in vivo and in vitro experiments. Functional assays were utilized to explore the role of the circRNAs derived from catenin beta 1 (mmu_circ_0001859, circ-Ctnnb1 herein) in regulating neuronal cell viability and apoptosis. Bioinformatics analysis and mechanism experiments were conducted to assess the underlying molecular mechanism of circ-Ctnnb1. Objective: We aimed to probe into the biological function of circ-Ctnnb1 in neuronal cells of SCI. Methods: The rat model of SCI and hypoxia-induced cell model were constructed to examine circ-Ctnnb1 expression in SCI through quantitative reverse transcription real-time polymerase chain reaction (RT-qPCR). Basso, Beattie and Bresnahan (BBB) score was utilized for evaluating the neurological function. Terminal-deoxynucleoitidyl Transferase Mediated Nick End labeling (TUNEL) assays were performed to assess the apoptosis of neuronal cells. RNase R and Actinomycin D (ActD) were used to treat cells to evaluate the stability of circ-Ctnnb1. Results: Circ-Ctnnb1 was highly expressed in SCI rat models and hypoxia-induced neuronal cells, and its deletion elevated the apoptosis rate of hypoxia-induced neuronal cells. Furthermore, circ-Ctnnb1 activated the Wnt/β-catenin signaling pathway via sponging mircoRNA-205-5p (miR-205-5p) to up-regulate Ctnnb1 and Wnt family member 2B (Wnt2b). Conclusion: Circ-Ctnnb1 promotes SCI through regulating Wnt/β-catenin signaling via modulating the miR-205-5p/Ctnnb1/Wnt2b axis.

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Small extracellular vesicles encapsulating CCL2 from activated astrocytes induce microglial activation and neuronal apoptosis after traumatic spinal cord injury

Journal of Neuroinflammation ◽

10.1186/s12974-021-02268-y ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Yuluo Rong ◽

Chengyue Ji ◽

Zhuanghui Wang ◽

Xuhui Ge ◽

Jiaxing Wang ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Extracellular Vesicles ◽

Neuronal Apoptosis ◽

Microglial Activation ◽

Neuronal Cells ◽

Cell Communication ◽

Bioactive Lipids ◽

Cord Injury

Abstract Background Spinal cord injury (SCI) is a severe traumatic disease which causes high disability and mortality rates. The molecular pathological features after spinal cord injury mainly involve the inflammatory response, microglial and neuronal apoptosis, abnormal proliferation of astrocytes, and the formation of glial scars. However, the microenvironmental changes after spinal cord injury are complex, and the interactions between glial cells and nerve cells remain unclear. Small extracellular vesicles (sEVs) may play a key role in cell communication by transporting RNA, proteins, and bioactive lipids between cells. Few studies have examined the intercellular communication of astrocytes through sEVs after SCI. The inflammatory signal released from astrocytes is known to initiate microglial activation, but its effects on neurons after SCI remain to be further clarified. Methods Electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blotting were applied to characterize sEVs. We examined microglial activation and neuronal apoptosis mediated by astrocyte activation in an experimental model of acute spinal cord injury and in cell culture in vitro. Results Our results indicated that astrocytes activated after spinal cord injury release CCL2, act on microglia and neuronal cells through the sEV pathway, and promote neuronal apoptosis and microglial activation after binding the CCR2. Subsequently, the activated microglia release IL-1β, which acts on neuronal cells, thereby further aggravating their apoptosis. Conclusion This study elucidates that astrocytes interact with microglia and neurons through the sEV pathway after SCI, enriching the mechanism of CCL2 in neuroinflammation and spinal neurodegeneration, and providing a new theoretical basis of CCL2 as a therapeutic target for SCI.

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An In Vitro Comparison of the Neurotrophic and Angiogenic Activity of Human and Canine Adipose-Derived Mesenchymal Stem Cells (MSCs): Translating MSC-Based Therapies for Spinal Cord Injury

Biomolecules ◽

10.3390/biom10091301 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1301

Author(s):

Ibtesam R. T. Al Delfi ◽

Chelsea R. Wood ◽

Louis D. V. Johnson ◽

Martyn D. Snow ◽

John F. Innes ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Cell Proliferation ◽

Endothelial Cell ◽

Neuronal Cell ◽

Endothelial Cell Migration ◽

Differentiation Potential ◽

Angiogenic Activity ◽

Cord Injury

The majority of research into the effects of mesenchymal stem cell (MSC) transplants on spinal cord injury (SCI) is performed in rodent models, which may help inform on mechanisms of action, but does not represent the scale and wound heterogeneity seen in human SCI. In contrast, SCI in dogs occurs naturally, is more akin to human SCI, and can be used to help address important aspects of the development of human MSC-based therapies. To enable translation to the clinic and comparison across species, we have examined the paracrine, regenerative capacity of human and canine adipose-derived MSCs in vitro. MSCs were initially phenotyped according to tissue culture plastic adherence, cluster of differentiation (CD) immunoprofiling and tri-lineage differentiation potential. Conditioned medium (CM) from MSC cultures was then assessed for its neurotrophic and angiogenic activity using established cell-based assays. MSC CM significantly increased neuronal cell proliferation, neurite outgrowth, and βIII tubulin immunopositivity. In addition, MSC CM significantly increased endothelial cell migration, cell proliferation and the formation of tubule-like structures in Matrigel assays. There were no marked or significant differences in the capacity of human or canine MSC CM to stimulate neuronal cell or endothelial cell activity. Hence, this study supports the use of MSC transplants for canine SCI; furthermore, it increases understanding of how this may subsequently provide useful information and translate to MSC transplants for human SCI.

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Methylprednisolone Induces Neuro-Protective Effects via the Inhibition of A1 Astrocyte Activation in Traumatic Spinal Cord Injury Mouse Models

Frontiers in Neuroscience ◽

10.3389/fnins.2021.628917 ◽

2021 ◽

Vol 15 ◽

Author(s):

Hong-jun Zou ◽

Shi-Wu Guo ◽

Lin Zhu ◽

Xu Xu ◽

Jin-bo Liu

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Mouse Models ◽

Neuronal Cells ◽

Neurological Function ◽

Traumatic Spinal Cord Injury ◽

Protective Effects ◽

Astrocyte Activation ◽

Cord Injury

Traumatic spinal cord injury (TSCI) leads to pathological changes such as inflammation, edema, and neuronal apoptosis. Methylprednisolone (MP) is a glucocorticoid that has a variety of beneficial effects, including decreasing inflammation and ischemic reaction, as well as inhibiting lipid peroxidation. However, the efficacy and mechanism of MP in TSCI therapy is yet to be deciphered. In the present study, MP significantly attenuated the apoptotic effects of H2O2 in neuronal cells. Western blot analysis demonstrated that the levels of apoptotic related proteins, Bax and cleaved caspase-3, were reduced while levels of anti-apoptotic Bcl-2 were increased. In vivo TUNEL assays further demonstrated that MP effectively protected neuronal cells from apoptosis after TSCI, and was consistent with in vitro studies. Furthermore, we demonstrated that MP could decrease expression levels of IBA1, Il-1α, TNFα, and C3 and suppress A1 neurotoxic reactive astrocyte activation in TSCI mouse models. Neurological function was evaluated using the Basso Mouse Scale (BMS) and Footprint Test. Results demonstrated that the neurological function of MP-treated injured mice was significantly increased. In conclusion, our study demonstrated that MP could attenuate astrocyte cell death, decrease microglia activation, suppress A1 astrocytes activation, and promote functional recovery after acute TSCI in mouse models.

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Ecto-domain phosphorylation promotes functional recovery from spinal cord injury

Scientific Reports ◽

10.1038/srep04972 ◽

2014 ◽

Vol 4 (1) ◽

Cited By ~ 5

Author(s):

Kenji Suehiro ◽

Yuka Nakamura ◽

Shuai Xu ◽

Youichi Uda ◽

Takafumi Matsumura ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Enhanced Recovery ◽

Neuronal Cell ◽

Cell Production ◽

Locomotor Function ◽

Neuronal Precursor Cells ◽

Cord Injury ◽

Adult Spinal Cord

Abstract Inhibition of Nogo-66 receptor (NgR) can promote recovery following spinal cord injury. The ecto-domain of NgR can be phosphorylated by protein kinase A (PKA), which blocks activation of the receptor. Here, we found that infusion of PKA plus ATP into the damaged spinal cord can promote recovery of locomotor function. While significant elongation of cortical-spinal axons was not detectable even in the rats showing enhanced recovery, neuronal precursor cells were observed in the region where PKA plus ATP were directly applied. NgR1 was expressed in neural stem/progenitor cells (NSPs) derived from the adult spinal cord. Both an NgR1 antagonist NEP1-40 and ecto-domain phosphorylation of NgR1 promote neuronal cell production of the NSPs, in vitro. Thus, inhibition of NgR1 in NSPs can promote neuronal cell production, which could contribute to the enhanced recovery of locomotor function following infusion of PKA and ATP.

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Knockdown of long non-coding RNA LEF1-AS1 attenuates apoptosis and inflammatory injury of microglia cells following spinal cord injury

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-020-02041-6 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Sheng-Yu Cui ◽

Wei Zhang ◽

Zhi-Ming Cui ◽

Hong Yi ◽

Da-Wei Xu ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Cell Viability ◽

Microglial Cells ◽

Protective Effects ◽

Loss Of Function ◽

Sprague Dawley ◽

Cord Injury ◽

Apoptosis And Inflammation

Abstract Background Spinal cord injury (SCI) is associated with health burden both at personal and societal levels. Recent assessments on the role of lncRNAs in SCI regulation have matured. Therefore, to comprehensively explore the function of lncRNA LEF1-AS1 in SCI, there is an urgent need to understand its occurrence and development. Methods Using in vitro experiments, we used lipopolysaccharide (LPS) to treat and establish the SCI model primarily on microglial cells. Gain- and loss of function assays of LEF1-AS1 and miR-222-5p were conducted. Cell viability and apoptosis of microglial cells were assessed via CCK8 assay and flow cytometry, respectively. Adult Sprague-Dawley (SD) rats were randomly divided into four groups: Control, SCI, sh-NC, and sh-LEF-AS1 groups. ELISA test was used to determine the expression of TNF-α and IL-6, whereas the protein level of apoptotic-related markers (Bcl-2, Bax, and cleaved caspase-3) was assessed using Western blot technique. Results We revealed that LncRNA LEF1-AS1 was distinctly upregulated, whereas miR-222-5p was significantly downregulated in LPS-treated SCI and microglial cells. However, LEF1-AS1 knockdown enhanced cell viability, inhibited apoptosis, as well as inflammation of LPS-mediated microglial cells. On the contrary, miR-222-5p upregulation decreased cell viability, promoted apoptosis, and inflammation of microglial cells. Mechanistically, LEF1-AS1 served as a competitive endogenous RNA (ceRNA) by sponging miR-222-5p, targeting RAMP3. RAMP3 overexpression attenuated LEF1-AS1-mediated protective effects on LPS-mediated microglial cells from apoptosis and inflammation. Conclusion In summary, these findings ascertain that knockdown of LEF1-AS1 impedes SCI progression via the miR-222-5p/RAMP3 axis.

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A Collagen-Based Scaffold for Promoting Neural Plasticity in a Rat Model of Spinal Cord Injury

Polymers ◽

10.3390/polym12102245 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2245

Author(s):

Jue-Zong Yeh ◽

Ding-Han Wang ◽

Juin-Hong Cherng ◽

Yi-Wen Wang ◽

Gang-Yi Fan ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Rat Model ◽

Neural Plasticity ◽

Collagen Scaffold ◽

Glial Scar ◽

Beneficial Effects ◽

Cord Injury

In spinal cord injury (SCI) therapy, glial scarring formed by activated astrocytes is a primary problem that needs to be solved to enhance axonal regeneration. In this study, we developed and used a collagen scaffold for glial scar replacement to create an appropriate environment in an SCI rat model and determined whether neural plasticity can be manipulated using this approach. We used four experimental groups, as follows: SCI-collagen scaffold, SCI control, normal spinal cord-collagen scaffold, and normal control. The collagen scaffold showed excellent in vitro and in vivo biocompatibility. Immunofluorescence staining revealed increased expression of neurofilament and fibronectin and reduced expression of glial fibrillary acidic protein and anti-chondroitin sulfate in the collagen scaffold-treated SCI rats at 1 and 4 weeks post-implantation compared with that in untreated SCI control. This indicates that the collagen scaffold implantation promoted neuronal survival and axonal growth within the injured site and prevented glial scar formation by controlling astrocyte production for their normal functioning. Our study highlights the feasibility of using the collagen scaffold in SCI repair. The collagen scaffold was found to exert beneficial effects on neuronal activity and may help in manipulating synaptic plasticity, implying its great potential for clinical application in SCI.

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