SiRNA in MSCs-Derived Exosomes Silences Ctgf Gene for Corticospinal Axon Regeneration and Locomotor Recovery in Spinal Cord Injury Rats

2020 ◽  
Author(s):  
Wei Huang ◽  
Mingjia Qu ◽  
Lu Li ◽  
Tao Liu ◽  
Ruimeng Duan ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Gene Therapy ◽  
Spinal Cord Injury ◽  
Axon Regeneration ◽  
Drug Loading ◽  
Glial Scar ◽  
Tissue Growth ◽  
Scar Formation ◽  
Cord Injury

Abstract As RNA interference (RNAi) received solicitous attention by many for its promising performance in gene therapy recently, and how to obtain a choice small interfering RNA (siRNA) vector has become a moot point at this moment. Exosomes (Exo) show advantages of long survival time in vivo, high transmission efficiency and easy penetration across the blood-brain/spinal cord barrier, renowned as excellent carriers of bioactive substances. Previous studies have confirmed the detrimental effect of connective tissue growth factor (CTGF) on axonal regeneration after spinal cord injury (SCI) via stimulating the unrestricted growth of glial scars. In this study, we applied mesenchymal stem cells (MSCs)-derived Exo as the delivery of synthesized siRNA, which were extracted from rat bone marrow. We constructed exosome-siRNA (Exo-siRNA) that could specifically silence Ctgf gene in the injury sites by electroporation. During the administration, we injected Exo-siRNAs into the tail vein of SCI rats, and their distribution and accumulation in the spinal cord were visualized by in vivo fluorescence imaging. Relevant in vivo and in vitro experiments in this study showed that Exo-siRNA not only effectively inhibited the expressions of Ctgf gene and glial scar formation related proteins, such as GFAP, vimentin fibronectin and laminin, in the injured spinal cord segments, but quenched inflammation, and thwarted neuronal apoptosis and reactive astrocytes and glial scar formation. Besides, it significantly up-regulated several neurotrophic factors and anti-inflammatory factors (e.g., TGF-β1), acting as a facilitator of axon regeneration of nerve-injured motor neurons. Thus, the motor function of SCI rats were remarkably promoted. In conclusion, this study has combined the thoroughness of gene therapy and the excellent drug-loading characteristics of Exo for the precise treatment of SCI, which will shed new light on the drug-loading field of Exo.

scholarly journals SiRNA in MSCs-Derived Exosomes Silences Ctgf Gene for Corticospinal Axon Regeneration and Locomotor Recovery in Spinal Cord Injury Rats

2019 ◽  
Author(s):  
Wei Huang ◽  
Mingjia Qu ◽  
Lu Li ◽  
Tao Liu ◽  
Ruimeng Duan ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Gene Therapy ◽  
Spinal Cord Injury ◽  
Axon Regeneration ◽  
Drug Loading ◽  
Glial Scar ◽  
Tissue Growth ◽  
Scar Formation ◽  
Cord Injury

Abstract As RNA interference (RNAi) received solicitous attention by many for its promising performance in gene therapy recently, and how to obtain a choice small interfering RNA (siRNA) vector has become a moot point at this moment. Exosomes (Exo) show advantages of long survival time in vivo, high transmission efficiency and easy penetration across the blood-brain/spinal cord barrier, renowned as excellent carriers of bioactive substances. Previous studies have confirmed the detrimental effect of connective tissue growth factor (CTGF) on axonal regeneration after spinal cord injury (SCI) via stimulating the unrestricted growth of glial scars. In this study, we applied mesenchymal stem cells (MSCs)-derived Exo as the delivery of synthesized siRNA, which were extracted from rat bone marrow. We constructed exosome-siRNA (Exo-siRNA) that could specifically silence Ctgf gene in the injury sites by electroporation.During the administration, we injected Exo-siRNAs into the tail vein of SCI rats, and their distribution and accumulation in the spinal cord were visualized by in vivo fluorescence imaging. Relevant in vivo and in vitro experiments in this study showed that Exo-siRNA not only effectively inhibited the expressions of Ctgf gene and glial scar formation related proteins, such as GFAP, vimentin fibronectin and laminin, in the injured spinal cord segments, but quenched inflammation, and thwarted neuronal apoptosis and reactive astrocytes and glial scar formation. Besides, it significantly up-regulated several neurotrophic factors and anti-inflammatory factors (e.g., TGF-β1), acting as a facilitator of axon regeneration of nerve-injured motor neurons. Thus, the motor function of SCI rats were remarkably promoted.In conclusion, this study has combined the thoroughness of gene therapy and the excellent drug-loading characteristics of Exo for the precise treatment of SCI, which will shed new light on the drug-loading field of Exo.

scholarly journals Extrinsic and Intrinsic Regulation of Axon Regeneration by MicroRNAs after Spinal Cord Injury

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Ping Li ◽  
Zhao-Qian Teng ◽  
Chang-Mei Liu
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Axonal Regeneration ◽  
Axon Regeneration ◽  
Therapeutic Potential ◽  
Glial Scar ◽  
Scar Formation ◽  
Extrinsic Factors ◽  
Cord Injury ◽  
The Central Nervous System

Spinal cord injury is a devastating disease which disrupts the connections between the brain and spinal cord, often resulting in the loss of sensory and motor function below the lesion site. Most injured neurons fail to regenerate in the central nervous system after injury. Multiple intrinsic and extrinsic factors contribute to the general failure of axonal regeneration after injury. MicroRNAs can modulate multiple genes’ expression and are tightly controlled during nerve development or the injury process. Evidence has demonstrated that microRNAs and their signaling pathways play important roles in mediating axon regeneration and glial scar formation after spinal cord injury. This article reviews the role and mechanism of differentially expressed microRNAs in regulating axon regeneration and glial scar formation after spinal cord injury, as well as their therapeutic potential for promoting axonal regeneration and repair of the injured spinal cord.

Spinal cord injury induction of lesional expression of profibrotic and angiogenic connective tissue growth factor confined to reactive astrocytes, invading fibroblasts and endothelial cells

2005 ◽  
Vol 2 (3) ◽  
pp. 319-326 ◽  
Author(s):  
Sabine Conrad ◽  
Hermann J. Schluesener ◽  
Mehdi Adibzahdeh ◽  
Jan M. Schwab
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Smooth Muscle ◽  
Glial Scar ◽  
Tissue Growth ◽  
Scar Formation ◽  
Reactive Astrocytes ◽  
Content Type ◽  
Cord Injury ◽  
Fine Print

Object. The glial scar composed of astrogliosis and extracellular matrix deposition represents a major impediment to axonal regeneration. The authors investigated the role of a novel profibrotic and angiogenic peptide connective tissue growth factor (CTGF [Hcs24/IGFBP-r2P]) in glial scar formation following spinal cord injury (SCI) in rats. Methods. The effects of SCI on CTGF expression during glial scar maturation 1 day to 1 month post-SCI were investigated using fluorescein-activated cell sorter (FACS) immunohistochemical analysis; these findings were compared with those obtained in sham-operated (control) spinal cords. The CTGF-positive cells accumulated at the spinal cord lesion site (p < 0.0001) corresponding to areas of glial scar formation. In the perilesional rim, CTGF expression was confined to invading vimentin-positive, glial fibrillary acidic protein (GFAP)—negative fibroblastoid cells, endothelial and smooth-muscle cells of laminin-positive vessels, and GFAP-positive reactive astrocytes. The CTGF-positive astrocytes coexpressed the activation-associated intermediate filaments nestin, vimentin (> 80%), and mesenchymal scar component fibronectin (50%). Conclusions. The restricted accumulation of CTGF-reactive astrocytes and CTGF-positive fibroblastoid cells lining the laminin-positive basal neolamina suggests participation of these cells in scar formation. In addition, perilesional upregulation of endothelial and smooth-muscle CTGF expression points to a role in blood—brain barrier function modulating edema-induced secondary damage.

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

Polymers ◽  
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.

scholarly journals Nitrous Oxide Impairs Axon Regeneration after Nervous System Injury in Male Rats

2019 ◽  
Vol 131 (5) ◽  
pp. 1063-1076
Author(s):  
Krista J. Stewart ◽  
Bermans J. Iskandar ◽  
Brenton M. Meier ◽  
Elias B. Rizk ◽  
Nithya Hariharan ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Nervous System ◽  
Nitrous Oxide ◽  
Folic Acid ◽  
Functional Recovery ◽  
Axon Regeneration ◽  
Retinal Ganglion ◽  
Cord Injury

Abstract Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New Background Nitrous oxide can induce neurotoxicity. The authors hypothesized that exposure to nitrous oxide impairs axonal regeneration and functional recovery after central nervous system injury. Methods The consequences of single and serial in vivo nitrous oxide exposures on axon regeneration in four experimental male rat models of nervous system injury were measured: in vitro axon regeneration in cell culture after in vivo nitrous oxide administration, in vivo axon regeneration after sharp spinal cord injury, in vivo axon regeneration after sharp optic nerve injury, and in vivo functional recovery after blunt contusion spinal cord injury. Results In vitro axon regeneration 48 h after a single in vivo 70% N2O exposure is less than half that in the absence of nitrous oxide (mean ± SD, 478 ± 275 um; n = 48) versus 210 ± 152 um (n = 48; P &lt; 0.0001). A single exposure to 80% N2O inhibits the beneficial effects of folic acid on in vivo axonal regeneration after sharp spinal cord injury (13.4 ± 7.1% regenerating neurons [n = 12] vs. 0.6 ± 0.7% regenerating neurons [n = 4], P = 0.004). Serial 80% N2O administration reverses the benefit of folic acid on in vivo retinal ganglion cell axon regeneration after sharp optic nerve injury (1277 ± 180 regenerating retinal ganglion cells [n = 7] vs. 895 ± 164 regenerating retinal ganglion cells [n = 7], P = 0.005). Serial 80% N2O exposures reverses the benefit of folic acid on in vivo functional recovery after blunt spinal cord contusion (estimate for fixed effects ± standard error of the estimate: folic acid 5.60 ± 0.54 [n = 9] vs. folic acid + 80% N2O 5.19 ± 0.62 [n = 7], P &lt; 0.0001). Conclusions These data indicate that nitrous oxide can impair the ability of central nervous system neurons to regenerate axons after sharp and blunt trauma.

scholarly journals Importance of the vasculature in cyst formation after spinal cord injury

2009 ◽  
Vol 11 (4) ◽  
pp. 432-437 ◽  
Author(s):  
Gemma E. Rooney ◽  
Toshiki Endo ◽  
Syed Ameenuddin ◽  
Bingkun Chen ◽  
Sandeep Vaishya ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Axonal Regeneration ◽  
Cyst Formation ◽  
Glial Scar ◽  
Scar Formation ◽  
Cystic Formation ◽  
Dural Closure ◽  
Surgical Methods ◽  
Cord Injury

Object Glial scar and cystic formation greatly contribute to the inhibition of axonal regeneration after spinal cord injury (SCI). Attempts to promote axonal regeneration are extremely challenging in this type of hostile environment. The objective of this study was to examine the surgical methods that may be used to assess the factors that influence the level of scar and cystic formation in SCI. Methods In the first part of this study, a complete transection was performed at vertebral level T9–10 in adult female Sprague-Dawley rats. The dura mater was either left open (control group) or was closed using sutures or hyaluronic acid. In the second part of the study, complete or subpial transection was performed, with the same dural closure technique applied to both groups. Histological analysis of longitudinal sections of the spinal cord was performed, and the percentage of scar and cyst formation was determined. Results Dural closure using sutures resulted in significantly less glial scar formation (p = 0.0248), while incorporation of the subpial transection surgical technique was then shown to significantly decrease cyst formation (p < 0.0001). Conclusions In this study, the authors demonstrated the importance of the vasculature in cyst formation after spinal cord trauma and confirmed the importance of dural closure in reducing glial scar formation.

Sign in / Sign up

Export Citation Format

Share Document