LncRNA SNHG16 promotes Schwann cell proliferation and migration to repair sciatic nerve injury

Role of Long Non-coding RNA in Nerve Regeneration

Nerve injury can be caused by a variety of factors. It often takes a long time to repair a nerve injury and severe nerve injury is even difficult to heal. Therefore, increasing attention has focused on nerve injury and repair. Long non-coding RNA (lncRNA) is a newly discovered non-coding RNA with a wide range of biological activities. Numerous studies have shown that a variety of lncRNAs undergo changes in expression after nerve injury, indicating that lncRNAs may be involved in various biological processes of nerve repair and regeneration. Herein, we summarize the biological roles of lncRNAs in neurons, glial cells and other cells during nerve injury and regeneration, which will help lncRNAs to be better applied in nerve injury and regeneration in the future.

HucMSC extracellular vesicles increasing SATB 1 to activate the Wnt/β-catenin pathway in 6-OHDA-induced Parkinson's disease model

Parkinson's disease (PD) is a degenerative disorder of the nervous system characterized by the loss of dopaminergic neurons and damage of neurons in the substantia nigra (SN) and striatum, resulting in impaired motor functions. This study aims to investigate how extracellular vesicles (EVs) derived from human umbilical cord mesenchymal stem cells (HucMSC) regulate Special AT-rich sequence-binding protein-1 (SATB 1) and influence Wnt/β-catenin pathway and autophagy in PD model. The PD model was induced by damaging SH-SY5Y cells and mice using 6-OHDA. According to the study, administering EVs every other day for 14 days improved the motor behavior of 6-OHDA-induced PD mice and reduced neuronal damage, including dopaminergic neurons. Treatment with EVs for 12 hours increased the viability of 6-OHDA-induced SH-SY5Y cells. The upregulation of SATB 1 expression with EV treatment resulted in the activation of the Wnt/β-catenin pathway in PD model and led to overexpression of β-catenin. Meanwhile, the expression of LC3 II was decreased, indicating alterations in autophagy. In conclusion, EVs could mitigate neuronal damage in the 6-OHDA-induced PD model by upregulating SATB 1 and activating Wnt/β-catenin pathway while also regulating autophagy. Further studies on the potential therapeutic applications of EVs for PD could offer new insights and strategies.

LncRNA GAS5 modulates Schwann cell function and enhances facial nerve injury repair via the miR-138-5p/CXCL12 axis

Facial nerve is an integral part of peripheral nerve. Schwann cells are important microglia involved in the repair and regulation of facial nerve injury. LncRNA growth arrest‑specific transcript 5 (GAS5) is involved in the behavioral regulation of Schwann cell and the regeneration of peripheral nervous system. However, there is little research about the effect of GAS5 on the repair of facial nerve injury (FNI) by regulating Schwann cells. This study aimed to investigate the role of GAS5 in Schwann cell function and FNI repair, focusing on the miR-138-5p/CXCL12 axis. Hematoxylin and eosin staining, Luxol fast blue staining, transmission electron microscope, and immunofluorescence (IF) experiments were used to verify the effect of GAS5 on FNI rats. Reverse transcription real-time polymerase chain reaction was performed to detect GAS5, miR-138-5p, and C-X-C motif chemokine ligand 12 (CXCL12) mRNA expression. IF staining was used to detect the inflorescence of S100 calcium binding protein B (S100β), SRY-box transcription factor 10 (SOX10), and tubulin beta 3 class III (β-Tubulin III). Glial fibrillary acidic protein (GFAP), nerve growth factor receptor (NGFR), S100β, brain derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), and CXCL12 proteins were detected using western blot. The 5-bromo-2'-deoxyuridine staining, Transwell, and flow cytometry assays were conducted to detect Schwann cell function. Dual-luciferase, RNA immunoprecipitation, and RNA pulldown assay were used to identify the interaction among GAS5, miR-138-5p, and CXCL12. Results found that GAS5 was downregulated in facial nerve tissues of FNI rats. Overexpressed GAS5 decreased facial grading, inhibited demyelination, and promoted proliferation, migration, and suppressed apoptosis of Schwann cells. Mechanistically, GAS5 was a sponge of miR-138-5p and positively regulated CXCL12 expression. GAS5 inhibition repressed CXCL12 expression and decreased cell proliferation and migration, increased apoptosis rate of Schwann cells by sponging miR-138-5p. In conclusion, overexpression of GAS5 accelerates facial nerve repair in FNI rats by regulating miR-138-5p/CXCL12 axis.

Advances of Schwann cells in peripheral nerve regeneration: From mechanism to cell therapy

Peripheral nerve injuries (PNIs) frequently occur due to various factors, including mechanical trauma such as accidents or tool-related incidents, as well as complications arising from diseases like tumor resection. These injuries frequently result in persistent numbness, impaired motor and sensory functions, neuropathic pain, or even paralysis, which can impose a significant financial burden on patients due to outcomes that often fall short of expectations. The most frequently employed clinical treatment for PNIs involves either direct sutures of the severed ends or bridging the proximal and distal stumps using autologous nerve grafts. However, autologous nerve transplantation may result in sensory and motor functional loss at the donor site, as well as neuroma formation and scarring. Transplantation of Schwann cells/Schwann cell-like cells has emerged as a promising cellular therapy to reconstruct the microenvironment and facilitate peripheral nerve regeneration. In this review, we summarize the role of Schwann cells and recent advances in Schwann cell therapy in peripheral nerve regeneration. We summarize current techniques used in cell therapy, including cell injection, 3D-printed scaffolds for cell delivery, cell encapsulation techniques, as well as the cell types employed in experiments, experimental models, and research findings. At the end of the paper, we summarize the challenges and advantages of various cells (including ESCs, iPSCs, and BMSCs) in clinical cell therapy. Our goal is to provide the theoretical and experimental basis for future treatments targeting peripheral nerves, highlighting the potential of cell therapy and tissue engineering as invaluable resources for promoting nerve regeneration.

Micro electrical fields induced MSC-sEVs attenuate neuronal cell apoptosis by activating autophagy via lncRNA MALAT1/miR-22-3p/SIRT1/AMPK axis in spinal cord injury

Spinal cord injury (SCI) is a traumatic condition of the central nervous system that causes paralysis of the limbs. Micro electric fields (EF) have been implicated in a novel therapeutic approach for nerve injury repair and regeneration, but the effects of human umbilical cord mesenchymal stem cell-derived small extracellular vesicles that are induced by micro electric fields (EF-sEVs) stimulation on SCI remain unknown. The aim of the present study was to investigate whether EF-sEVs have therapeutic effects a rat model of SCI. EF-sEVs and normally conditioned human umbilical cord mesenchymal stem cells-derived small extracellular vesicles (CON-sEVs) were collected and injected intralesionally into SCI model rats to evaluate the therapeutic effects. We detect the expression of candidate long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (lncRNA-MALAT1) in EF-sEVs and CON-sEVs. The targets and downstream effectors of lncRNA-MALAT1 were investigated using luciferase reporter assays. Using both in vivo and in vitro experiments, we demonstrated that EF-sEVs increased autophagy and decreased apoptosis after SCI, which promoted the recovery of motor function. We further confirmed that the neuroprotective effects of EF-sEVs in vitro and in vivo correlated with the presence of encapsulated lncRNA-MALAT1 in sEVs. lncRNA-MALAT1 targeted miR-22-3p via sponging, reducing miR-22-3p's suppressive effects on its target, SIRT1, and this translated into AMPK phosphorylation and increased levels of the antiapoptotic protein Bcl-2. Collectively, the present study identified that the lncRNA-MALAT1 in EF-sEVs plays a neuroprotective role via the miRNA-22-3p/SIRT1/AMPK axis and offers a fresh perspective and a potential therapeutic approach using sEVs to improve SCI.

LncRNAs and PTEN/PI3K signaling: A symphony of regulation in cancer biology

The Emergence of Long Non-coding RNAs (lncRNAs) as Key Regulators in Diverse Biological Processes: A Paradigm Shift in Understanding Gene Expression and its Impact on Cancer. The PTEN/PI3K pathway, a pivotal signaling cascade involved in cancer progression, orchestrates critical cellular functions such as survival, proliferation, and growth. In light of these advances, our investigation delves into the intricate and multifaceted interplay between lncRNAs and the PTEN/PI3K signaling pathway, unearthing previously undisclosed mechanisms that underpin cancer growth and advancement. These elusive lncRNAs exert their influence through direct targeting of the PTEN/PI3K pathway or by skillfully regulating the expression and activity of specific lncRNAs. This comprehensive review underscores the paramount significance of the interaction between lncRNAs and the PTEN/PI3K signaling pathway in cancer biology, unveiling an auspicious avenue for novel diagnostic tools and targeted therapeutic interventions. In this review, we navigate through the functional roles of specific lncRNAs in modulating PTEN/PI3K expression and activity. Additionally, we scrutinize their consequential effects on downstream components of the PTEN/PI3K pathway, unraveling the intricacies of their mutual regulation. By advancing our understanding of this complex regulatory network, this study holds the potential to revolutionize the landscape of cancer research, paving the way for tailored and efficacious treatments to combat this devastating disease.

Sox2ot /miR-9 /Cthrc1 Promote Proliferation and Migration of Schwann Cells Following Nerve Injury

The effects of traditional treatments for peripheral nerve injury (PNI) are not ideal, which has prompted the identification of new therapeutic strategies. As unique glial cells in the peripheral nervous system, Schwann cells (SCs) play an important role in the repair of PNI. Recent studies have demonstrated that long noncoding RNAs (lncRNAs) are involved in the regulation of nerve repair after PNI. In this study, we used microarray technology to detect mRNA and lncRNA expression profiles at different time points after PNI and identified lncRNA Sox2ot-miR-9-Cthrc1 as a competitive endogenous RNA (ceRNA) for further investigation. Expression of lncRNA Sox2ot was increased after PNI, and overexpression of Sox2ot promoted SCs migration and proliferation. Mechanistic analyses confirmed that Sox2ot can regulate the expression of Cthrc1 through competitive adsorption of miR-9 in SCs, ultimately affecting SCs migration and proliferation. Our findings reveal the key role of lncRNA Sox2ot in nerve regeneration and provide a new direction for PNI treatment.

Unleashing Intrinsic Growth Pathways in Regenerating Peripheral Neurons

Common mechanisms of peripheral axon regeneration are recruited following diverse forms of damage to peripheral nerve axons. Whether the injury is traumatic or disease related neuropathy, reconnection of axons to their targets is required to restore function. Supporting peripheral axon regrowth, while not yet available in clinics, might be accomplished from several directions focusing on one or more of the complex stages of regrowth. Direct axon support, with follow on participation of supporting Schwann cells is one approach, emphasized in this review. However alternative approaches might include direct support of Schwann cells that instruct axons to regrow, manipulation of the inflammatory milieu to prevent ongoing bystander axon damage, or use of inflammatory cytokines as growth factors. Axons may be supported by a growing list of growth factors, extending well beyond the classical neurotrophin family. The understanding of growth factor roles continues to expand but their impact experimentally and in humans has faced serious limitations. The downstream signaling pathways that impact neuron growth have been exploited less frequently in regeneration models and rarely in human work, despite their promise and potency. Here we review the major regenerative signaling cascades that are known to influence adult peripheral axon regeneration. Within these pathways there are major checkpoints or roadblocks that normally check unwanted growth, but are an impediment to robust growth after injury. Several molecular roadblocks, overlapping with tumour suppressor systems in oncology, operate at the level of the perikarya. They have impacts on overall neuron plasticity and growth. A second approach targets proteins that largely operate at growth cones. Addressing both sites might offer synergistic benefits to regrowing neurons. This review emphasizes intrinsic aspects of adult peripheral axon regeneration, emphasizing several molecular barriers to regrowth that have been studied in our laboratory.

Advancing Our Understanding of the Chronically Denervated Schwann Cell: A Potential Therapeutic Target?

Outcomes for patients following major peripheral nerve injury are extremely poor. Despite advanced microsurgical techniques, the recovery of function is limited by an inherently slow rate of axonal regeneration. In particular, a time-dependent deterioration in the ability of the distal stump to support axonal growth is a major determinant to the failure of reinnervation. Schwann cells (SC) are crucial in the orchestration of nerve regeneration; their plasticity permits the adoption of a repair phenotype following nerve injury. The repair SC modulates the initial immune response, directs myelin clearance, provides neurotrophic support and remodels the distal nerve. These functions are critical for regeneration; yet the repair phenotype is unstable in the setting of chronic denervation. This phenotypic instability accounts for the deteriorating regenerative support offered by the distal nerve stump. Over the past 10 years, our understanding of the cellular machinery behind this repair phenotype, in particular the role of c-Jun, has increased exponentially, creating opportunities for therapeutic intervention. This review will cover the activation of the repair phenotype in SC, the effects of chronic denervation on SC and current strategies to 'hack' these cellular pathways toward supporting more prolonged periods of neural regeneration.

Transcriptome Profiles of IncRNA and mRNA Highlight the Role of Ferroptosis in Chronic Neuropathic Pain With Memory Impairment

Background: Chronic neuropathic pain is commonly associated with memory loss, which increases the risk of dementia, lowers life quality and spending. On the other hand, the molecular processes are unknown, and effective therapies have yet to be discovered. Long non-coding RNAs (lncRNAs) are emerging potential therapeutic targets for chronic pain, but their role in chronic pain-induced memory impairment is unknown. Methods: We established a CCI-induced memory impairment rat model. To investigate and validate the gene expression alterations in the hippocampus of CCI-induced memory impairment, we used RNA-Seq, bioinformatics analysis, qRT-PCR, western blot, immunostaining, Nissl staining, and Diaminobenzidine-enhanced Perls' stain. Results: CCI rats displayed long-term memory deficits in the Y maze and novel objective recognition tests, and chronic mechanical and thermal pain hypersensitivity in the hind paws. We found a total of 179 differentially expressed mRNAs (DEmRNAs) (81 downregulated and 98 upregulated) and 191 differentially expressed long noncoding RNAs (DElncRNAs) (87 downregulated and 105 upregulated) between the hippocampus CA1 of CCI-induced memory impairment model and the sham control, using RNA-Seq expression profiles. The most enriched pathways involving oxidation and iron metabolism were explored using a route and function pathway analysis of DEmRNAs and DElncRNAs. We also discovered that ATF3 was considerably overexpressed in the hippocampal CA1 area, and gene markers of ferroptosis, such as GPX4, SLC7A11, SLC1A5, and PTGS2, were dysregulated in the CCI-induced memory impairment paradigm. Furthermore, in the hippocampus CA1 of CCI-induced memory impairment, lipid peroxidation and iron overload were considerably enhanced. Fer-1 treatment reversed ferroptosis damage of CCI with memory impairment model. Finally, in CCI-induced memory impairment, a competing RNA network analysis of DElncRNAs and DEmRNAs was performed to investigate the putative regulatory link of DElncRNAs on DEmRNAs via miRNA sponging. Conclusion: Using RNA-Seq, we created a genome-wide profile of the whole hippocampus of a rat model of CCI-induced memory impairment. In the hippocampus, pathways and function analyses revealed numerous intriguing genes and pathways involved in ferroptosis and memory impairment in response to chronic pain stress. As a result, our research may aid in the identification of potential and effective treatments for CCI-induced memory impairment.