Engineering Biomaterials to Influence Oligodendroglial Growth, Maturation, and Myelin Production

2016 ◽  
Vol 202 (1-2) ◽  
pp. 85-101 ◽  
Author(s):  
Lauren N. Russell ◽  
Kyle J. Lampe

Millions of people suffer from damage or disease to the nervous system that results in a loss of myelin, such as through a spinal cord injury or multiple sclerosis. Diminished myelin levels lead to further cell death in which unmyelinated neurons die. In the central nervous system, a loss of myelin is especially detrimental because of its poor ability to regenerate. Cell therapies such as stem or precursor cell injection have been investigated as stem cells are able to grow and differentiate into the damaged cells; however, stem cell injection alone has been unsuccessful in many areas of neural regeneration. Therefore, researchers have begun exploring combined therapies with biomaterials that promote cell growth and differentiation while localizing cells in the injured area. The regrowth of myelinating oligodendrocytes from neural stem cells through a biomaterials approach may prove to be a beneficial strategy following the onset of demyelination. This article reviews recent advancements in biomaterial strategies for the differentiation of neural stem cells into oligodendrocytes, and presents new data indicating appropriate properties for oligodendrocyte precursor cell growth. In some cases, an increase in oligodendrocyte differentiation alongside neurons is further highlighted for functional improvements where the biomaterial was then tested for increased myelination both in vitro and in vivo.

2013 ◽  
Vol 2 (10) ◽  
pp. 731-744 ◽  
Author(s):  
Christopher J. Sontag ◽  
Hal X. Nguyen ◽  
Noriko Kamei ◽  
Nobuko Uchida ◽  
Aileen J. Anderson ◽  
...  

2022 ◽  
Vol 2022 ◽  
pp. 1-22
Author(s):  
Qingqi Meng ◽  
Zhiteng Chen ◽  
Qingyuan Gao ◽  
Liqiong Hu ◽  
Qilong Li ◽  
...  

Background. Neurodegenerative diseases, such as Alzheimer’s disease, and traumatic brain and spinal cord injury (SCI) are prevalent in clinical practice. Inhibition of hyperactive inflammation and proliferation of endogenous neural stem cells (NSCs) is a promising treatment strategy for SCI. Our previous studies demonstrated the beneficial effects of rosiglitazone (Rosi) on SCI, but its roles in inflammation inhibition and proliferation of NSCs are unknown. Methods. SCI in a rat model was established, and the effects of Rosi on motor functions were assessed. The effects of Rosi on NSC proliferation and the underlying mechanisms were explored in details. Results. We showed that Rosi ameliorated impairment of moto functions in SCI rats, inhibited inflammation, and promoted proliferation of NSCs in vivo. Rosi increased ATP production through enhancing glycolysis but not oxidative phosphorylation. Rosi reduced mitophagy by downregulating PTEN-induced putative kinase 1 (PINK1) transcription to promote NSC proliferation, which was effectively reversed by an overexpression of PINK1 in vitro. Through KEGG analysis and experimental validations, we discovered that Rosi reduced the expression of forkhead box protein O1 (FOXO1) which was a critical transcription factor of PINK1. Three FOXO1 consensus sequences (FCSs) were found in the first intron of the PINK1 gene, which could be potentially binding to FOXO1. The proximal FCS (chr 5: 156680169–156680185) from the translation start site exerted a more significant influence on PINK1 transcription than the other two FCSs. The overexpression of FOXO1 entirely relieved the inhibition of PINK1 transcription in the presence of Rosi. Conclusions. Besides inflammation inhibition, Rosi suppressed mitophagy by reducing FOXO1 to decrease the transcription of PINK1, which played a pivotal role in accelerating the NSC proliferation.


2002 ◽  
Vol 11 (3) ◽  
pp. 297-307 ◽  
Author(s):  
Daniel A. Castellanos ◽  
Pantelis Tsoulfas ◽  
Beata R. Frydel ◽  
Shyam Gajavelli ◽  
Jean-Claude Bes ◽  
...  

Although CNS axons have the capacity to regenerate after spinal cord injury when provided with a permissive substrate, the lack of appropriate synaptic target sites for regenerating fibers may limit restoration of spinal circuitry. Studies in our laboratory are focused on utilizing neural stem cells to provide new synaptic target sites for regenerating spinal axons following injury. As an initial step, rat neural precursor cells genetically engineered to overexpress the tyrosine kinase C (trkC) neurotrophin receptor were transplanted into the intact rat spinal cord to evaluate their survival and differentiation. Cells were either pretreated in vitro prior to transplantation with trkC ligand neurotrophin-3 (NT-3) to initiate differentiation or exposed to NT-3 in vivo following transplantation via gelfoam or Oxycel©. Both treatments enhanced survival of trkC-overexpressing stem cells to nearly 100%, in comparison with approximately 30–50% when either NT-3 or trkC was omitted. In addition, increased migration of trkC-overexpressing cells throughout the spinal gray matter was noted, particularly following in vivo NT-3 exposure. The combined trkC expression and NT-3 treatment appeared to reduce astrocytic differentiation of transplanted neural precursors. Decreased cavitation and increased β-tubulin fibers were noted in the vicinity of transplanted cells, although the majority of transplanted cells appeared to remain in an undifferentiated state. These findings suggest that genetically engineered neural stem cells in combination with neurotrophin treatment may be a useful addition to strategies for repair of spinal neurocircuitry following injury.


2021 ◽  
Author(s):  
Zhijian Cheng ◽  
Wen Zhu ◽  
Xijing He ◽  
Cao Kai ◽  
Jin Li ◽  
...  

Abstract After spinal cord injury, grafted neural stem cells (NSCs) can migrate toward injured area, where there are a large number of bone marrow derived macrophage. However, little is known about the effect of M1 macrophage from bone marrow on NSCs migration and the mechanism responsible for migratory responses of grafted NSCs in vitro and in vivo. Migration of NSCs were conducted by using the transwell chamber and SCI model. Conditioned medium from M1 macrophages (M1-CM) can attract NSCs migration in vitro. The number of migrated C-C chemokine receptor 2 (CCR2) -/- NSCs induced by M1-CM were significantly decreased compared with wild type (WT) NSCs (P<0.05). Furthermore, compared with M0 macrophages, the production of MCP-1 by M1 macrophages was significantly increased and M1-CM treated with anti-MCP-1 antibody to neutralize MCP-1 can lead to a significant reduction of NSCs migration (P<0.05). In addition, Western blot showed that ERK1/2 was dramatically activated following the stimuli of M1-CM and then ERK inhibitor can also inhibit M1-CM-mediated MSCs migration. Finally, CCR2 was needed for grafted NSCs migration toward injured area. Bone marrow derived M1 macrophage persisted within the epicenter of injured area and the expression of MCP-1 mRNA was significantly increased 7days after SCI (P<0.05). These results demonstrated the effect of M1 macrophages on NSCs migration and the important role of MCP-1/CCR2 and ERK signal pathway on M1-CM-induced NSCs migration.


Author(s):  
Prithiv K R Kumar

Stem cells have the capacity to differentiate into any type of cell or organ. Stems cell originate from any part of the body, including the brain. Brain cells or rather neural stem cells have the capacitive advantage of differentiating into the central nervous system leading to the formation of neurons and glial cells. Neural stem cells should have a source by editing DNA, or by mixings chemical enzymes of iPSCs. By this method, a limitless number of neuron stem cells can be obtained. Increase in supply of NSCs help in repairing glial cells which in-turn heal the central nervous system. Generally, brain injuries cause motor and sensory deficits leading to stroke. With all trials from novel therapeutic methods to enhanced rehabilitation time, the economy and quality of life is suppressed. Only PSCs have proven effective for grafting cells into NSCs. Neurons derived from stem cells is the only challenge that limits in-vitro usage in the near future.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii88-ii88
Author(s):  
Alison Mercer-Smith ◽  
Wulin Jiang ◽  
Alain Valdivia ◽  
Juli Bago ◽  
Scott Floyd ◽  
...  

Abstract INTRODUCTION Non-small cell lung cancer (NSCLC) is the most common cancer to form brain metastases. Radiation treatment is standard-of-care, but recurrence is still observed in 40% of patients. An adjuvant treatment is desperately needed to track down and kill tumor remnants after radiation. Tumoritropic neural stem cells (NSCs) that can home to and deliver a cytotoxic payload offer potential as such an adjuvant treatment. Here we show the transdifferentiation of human fibroblasts into tumor-homing induced neural stem cells (hiNSCs) that secrete the cytotoxic protein TRAIL (hiNSC-TRAIL) and explore the use of hiNSC-TRAIL to treat NSCLC brain metastases. METHODS To determine the migratory capacity of hiNSCs, hiNSCs were infused intracerebroventricularly (ICV) into mice bearing established bilateral NSCLC H460 brain tumors. hiNSC accumulation at tumor foci was monitored using bioluminescent imaging and post-mortem fluorescent analysis. To determine synergistic effects of radiation with TRAIL on NSCLC, we performed in vitro co-culture assays and isobologram analysis. In vivo, efficacy was determined by tracking the progression and survival of mice bearing intracranial H460 treated with hiNSC-TRAIL alone or in combination with 2 Gy radiation. RESULTS/CONCLUSION Following ICV infusion, hiNSCs persisted in the brain for &gt; 1 week and migrated from the ventricles to colocalize with bilateral tumor foci. In vitro, viability assays and isobologram analysis revealed the combination treatment of hiNSC-TRAIL and 2 Gy radiation induced synergistic killing (combination index=0.64). In vivo, hiNSC-TRAIL/radiation combination therapy reduced tumor volumes &gt; 90% compared to control-treated animals while radiation-only and hiNSC-TRAIL-only treated mice showed 21% and 52% reduced volumes, respectively. Dual-treatment extended survival 40%, increasing survival from a median of 20 days in controls to 28 days in the treatment group. These results suggest hiNSC-TRAIL can improve radiation therapy for NSCLC brain metastases and could potentially improve outcomes for patients suffering from this aggressive form of cancer.


RSC Advances ◽  
2017 ◽  
Vol 7 (65) ◽  
pp. 41098-41104 ◽  
Author(s):  
Ruirui Yang ◽  
Caixia Xu ◽  
Tao Wang ◽  
Yuanqi Wang ◽  
Jingnan Wang ◽  
...  

The enhancement of the biological properties of hydrogels by surface modifying with bioactive molecules is of great significance, especially for the treatment of central nervous system injury by combining engrafted cells.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi29-vi30
Author(s):  
Shreya Budhiraja ◽  
Shivani Baisiwala ◽  
Khizar Nandoliya ◽  
Li Chen ◽  
Crismita Dmello ◽  
...  

Abstract Glioblastoma (GBM) is the most aggressive and common type of adult malignant brain tumor, with a median survival of only 21 months. To identify which genes drive its highly aggressive phenotype, we performed a genome-wide CRISPR-Cas9 knockout screen. Results showed substantial enrichment of ~160 novel essential oncogenic driver genes and pathways, including a previously unstudied gene THOC1—involved in RNA processing—that showed significant elevations in expression at RNA and protein levels (p&lt; 0.05) in GBM, as well as a significant survival benefit in patient datasets when downregulated (p&lt; 0.05). Knocking out THOC1 resulted in cell death in multiple GBM patient-derived xenograft (PDX) lines and extended survival compared to the controls (p&lt; 0.01) in vivo. Overexpression of THOC1 in neural stem cells resulted in transformation to a cancerous phenotype, as evidenced by sphere formation in a soft agar assay (p&lt; 0.01) and in vivo tumor engraftment assays. Further investigation of THOC1 through immunoprecipitation in neural stem cells and multiple GBM lines showed significant interaction in GBM with histone deacetylase complex SIN3A, involved in recruiting major histone deacetylases in order to close the DNA and prevent the accumulation of R-loops, RNA:DNA hybrids that pose a threat to genomic stability. Additional investigation revealed that THOC1-knockdowns in vitro induced R-loop formation and DNA damage, while THOC1-overexpression in vitro resulted in an untenable decrease in R-loops and DNA damage, suggesting that the THOC1-SIN3A axis is elevated in GBM in order to prevent the accumulation of genotoxic R-loops. Additionally, histone deacetylase activity was shown to be elevated in THOC1-overexpression conditions and reduced in THOC1-knockdown conditions, confirming that the THOC1-SIN3A axis functions to prevent R-loop accumulation through the epigenetic regulation. In summary, our whole-genome CRISPR-Cas9 knockout screen has identified a promising therapeutic target for GBM—a disease desperately in need of therapeutic innovations.


2020 ◽  
Author(s):  
Tianyu Han ◽  
Peiwen Song ◽  
Xiang Xia ◽  
Ying Wang ◽  
Huang Fang ◽  
...  

Abstract Background: Mesenchymal stem cells (MSCs) are a promising therapy for spinal cord injury (SCI) as they can provide a favorable environment for the regrowth of neurons and axons by inhibiting receptor-regulated Smads (R-Smads) in endogenous neural stem cells (NSCs). However, their mechanism of action and effect on the expression of inhibitory Smads (I-Smads) remains unclear.Method: Conditioned medium (CM) was collected from bone marrow MSCs (BMSCs) isolated from rats with SCIs, and its effect on the regulation of Smad 6 expression was tested in vitro (in NSCs) and in vivo (SCI rats). Western blot analysis and immunohistochemistry staining were used to investigate the proportion of neurons and astrocytes in vitro and in vivo. BBB scores were used to assess the neurological outcome of SCI rats at different time points.Results: BMSC-CM could upregulate Smad 6 expression in vitro. BMSC-CM-induced upregulation was suppressed by pre-treatment with the TGF-β type I receptor kinase inhibitor SB431542. BMSC-CM was able to promote the differentiation of NSCs to neurons; Smad 6 knockdown in NSCs partly weakened this effect on neural differentiation. In vivo, Smad 6 expression in the later phase of injury was closely associated with BMSC-CM treatment. Conclusion: BMSC-CM can upregulate Smad 6 expression by the secretion of TGF-β. It promotes the differentiation of NSCs into neurons, partly through upregulation of Smad 6.


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