Comparative Effects of Human Neural Stem Cells and Oligodendrocyte Progenitor Cells on the Neurobehavioral Disorders of Experimental Autoimmune Encephalomyelitis Mice

Alterations of Oligodendrocyte and Myelin Energy Metabolism in Multiple Sclerosis

Multiple sclerosis (MS) is a complex autoimmune disease of the central nervous system (CNS), characterized by demyelination and neurodegeneration. Oligodendrocytes play a vital role in maintaining the integrity of myelin, the protective sheath around nerve fibres essential for efficient signal transmission. However, in MS, oligodendrocytes become dysfunctional, leading to myelin damage and axonal degeneration. Emerging evidence suggests that metabolic changes, including mitochondrial dysfunction and alterations in glucose and lipid metabolism, contribute significantly to the pathogenesis of MS. Mitochondrial dysfunction is observed in both immune cells and oligodendrocytes within the CNS of MS patients. Impaired mitochondrial function leads to energy deficits, affecting crucial processes such as impulse transmission and axonal transport, ultimately contributing to neurodegeneration. Moreover, mitochondrial dysfunction is linked to the generation of reactive oxygen species (ROS), exacerbating myelin damage and inflammation. Altered glucose metabolism affects the energy supply required for oligodendrocyte function and myelin synthesis. Dysregulated lipid metabolism results in changes to the composition of myelin, affecting its stability and integrity. Importantly, low levels of polyunsaturated fatty acids in MS are associated with upregulated lipid metabolism and enhanced glucose catabolism. Understanding the intricate relationship between these mechanisms is crucial for developing targeted therapies to preserve myelin and promote neurological recovery in individuals with MS. Addressing these metabolic aspects may offer new insights into potential therapeutic strategies to halt disease progression and improve the quality of life for MS patients.

The Integration of Cell Therapy and Biomaterials as Treatment Strategies for Remyelination

Multiple sclerosis (MS) is a chronic degenerative autoimmune disease of the central nervous system that causes inflammation, demyelinating lesions, and axonal damage and is associated with a high rate of early-onset disability. Disease-modifying therapies are used to mitigate the inflammatory process in MS but do not promote regeneration or remyelination; cell therapy may play an important role in these processes, modulating inflammation and promoting the repopulation of oligodendrocytes, which are responsible for myelin repair. The development of genetic engineering has led to the emergence of stable, biocompatible biomaterials that may promote a favorable environment for exogenous cells. This review summarizes the available evidence about the effects of transplantation of different types of stem cells reported in studies with several animal models of MS and clinical trials in human patients. We also address the advantages of combining cell therapy with biomaterials.

Modified Industrial Three-Dimensional Polylactic Acid Scaffold Cell Chip Promotes the Proliferation and Differentiation of Human Neural Stem Cells

In this study, we fabricated a three-dimensional (3D) scaffold using industrial polylactic acid (PLA), which promoted the proliferation and differentiation of human neural stem cells. An industrial PLA 3D scaffold (IPTS) cell chip with a square-shaped pattern was fabricated via computer-aided design and printed using a fused deposition modeling technique. To improve cell adhesion and cell differentiation, we coated the IPTS cell chip with gold nanoparticles (Au-NPs), nerve growth factor (NGF) protein, an NGF peptide fragment, and sonic hedgehog (SHH) protein. The proliferation of F3.Olig2 neural stem cells was increased in the IPTS cell chips coated with Au-NPs and NGF peptide fragments when compared with that of the cells cultured on non-coated IPTS cell chips. Cells cultured on the IPTS-SHH cell chip also showed high expression of motor neuron cell-specific markers, such as HB9 and TUJ-1. Therefore, we suggest that the newly engineered industrial PLA scaffold is an innovative tool for cell proliferation and motor neuron differentiation.

Neural stem cells derived from primitive mesenchymal stem cells reversed disease symptoms and promoted neurogenesis in an experimental autoimmune encephalomyelitis mouse model of multiple sclerosis

Background

Multiple sclerosis (MS) is an autoimmune inflammatory disease of the central nervous system (CNS). MS affects millions of people and causes a great economic and societal burden. There is no cure for MS. We used a novel approach to investigate the therapeutic potential of neural stem cells (NSCs) derived from human primitive mesenchymal stem cells (MSCs) in an experimental autoimmune encephalomyelitis (EAE) mouse model of MS.

Methods

MSCs were differentiated into NSCs, labeled with PKH26, and injected into the tail vein of EAE mice. Neurobehavioral changes in the mice assessed the effect of transplanted cells on the disease process. The animals were sacrificed two weeks following cell transplantation to collect blood, lymphatic, and CNS tissues for analysis. Transplanted cells were tracked in various tissues by flow cytometry. Immune infiltrates were determined and characterized by H&E and immunohistochemical staining, respectively. Levels of immune regulatory cells, Treg and Th17, were analyzed by flow cytometry. Myelination was determined by Luxol fast blue staining and immunostaining. In vivo fate of transplanted cells and expression of inflammation, astrogliosis, myelination, neural, neuroprotection, and neurogenesis markers were investigated by using immunohistochemical and qRT-PCR analysis.

Results

MSC-derived NSCs expressed specific neural markers, NESTIN, TUJ1, VIMENTIN, and PAX6. NSCs improved EAE symptoms more than MSCs when transplanted in EAE mice. Post-transplantation analyses also showed homing of MSCs and NSCs into the CNS with concomitant induction of an anti-inflammatory response, resulting in reducing immune infiltrates. NSCs also modulated Treg and Th17 cell levels in EAE mice comparable to healthy controls. Luxol fast blue staining showed significant improvement in myelination in treated mice. Further analysis showed that NSCs upregulated genes involved in myelination and neuroprotection but downregulated inflammatory and astrogliosis genes more significantly than MSCs. Importantly, NSCs differentiated into neural derivatives and promoted neurogenesis, possibly by modulating BDNF and FGF signaling pathways.

Conclusions

NSC transplantation reversed the disease process by inducing an anti-inflammatory response and promoting myelination, neuroprotection, and neurogenesis in EAE disease animals. These promising results provide a basis for clinical studies to treat MS using NSCs derived from primitive MSCs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02563-8.

Study on the Safety of Human Oligodendrocyte Precursor Cell Transplantation in Young Animals and Its Efficacy on Myelination

Oligodendrocyte precursor cells (OPCs) can differentiate into myelinating oligodendrocytes during embryonic development, thereby representing an important potential source for myelin repair or regeneration. To the best of our knowledge, there are very few OPCs from human sources (human-derived OPCs [hOPCs]). In this study, we aimed to evaluate the safety and remyelination capacity of hOPCs developed in our laboratory, transplanted into the lateral ventricles of young animals. Several acute and chronic toxicity experiments were conducted in which different doses of hOPCs were transplanted into the lateral ventricles of Sprague–Dawley rats of different ages. The toxicity, biodistribution, and tumor formation ability of the injected hOPCs were examined by evaluating the rats' vital signs, developmental indicators, neural reflexes, as well as by hematology, immunology, and pathology. In addition, the hOPCs were transplanted into the corpus callosum of the shiverer mouse to verify cell myelination efficacy. Overall, our results show that transplanted hOPCs into young mice are nontoxic to their organ function or immune system. The transplanted cells engrafted in the brain and did not appear in other organs, nor did they cause tissue proliferation or tumor formation. In terms of efficacy, the transplanted hOPCs were able to form myelin in the corpus callosum, alleviate the trembling phenotype of shiverer mice, and promote normal development. The transplantation of hOPCs is safe; they can effectively form myelin in the brain, thereby providing a theoretical basis for the future clinical transplantation of hOPCs.

Neuroprotective effects of human neural stem cells over-expressing choline acetyltransferase in a middle cerebral artery occlusion model

Stroke is one of the most-devastating brain diseases causing acute death or permanent disability. Although tissue-type plasminogen activator was approved by Food and Drug Administration for early reperfusion of the occluded vessels, oxidative injury may cause extensive brain infarction. Accordingly, there is a need for effective neuroprotection during reperfusion, and stem cell-based therapeutic approaches should fulfill this requirement. We established human neural stem cells (NSCs) encoding gene of choline acetyltransferase (F3.ChAT), an acetylcholine-synthesizing enzyme, and investigated whether infusion of the F3.ChAT cells attenuate the ischemia-reperfusion brain damage in a rat model of middle cerebral artery occlusion (MCAO). F3.ChAT cells were found to produce much higher amounts of ChAT as well as neuroprotective and anti-inflammatory neurotrophins than their parental F3 NSCs. After 2-h occlusion, the artery was reperfused, along with intravenous infusion of the stem cells (1 × 10⁶ cells/rat). Administration of the F3.ChAT cells markedly reduced the infarction volume and improved both the cognitive dysfunction and behavioural deficits of MCAO animals, in which F3.ChAT cells were superior to F3 cells. F3.ChAT cells not only restored microtubule-associated protein-2, a neuronal cytoskeletal protein, and preserved microvessels, but also suppressed lipid peroxidation, pro-inflammatory cytokines, glial fibrillary acidic protein, and intercellular adhesion molecule-1 in the brain tissues. The results demonstrate that early intravenous infusion of NSCs expressing ChAT and neurotrophins attenuate brain and capillary injuries and restore neurobehavioural functions via neuroprotective and anti-inflammatory activities, and that F3.ChAT cells could be a candidate for the neuroprotection and functional recovery of acute stroke patients.

Combination therapy with interferon beta-1a and sesame oil in multiple sclerosis

OBJECTIVES

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system. Several effector mechanisms are involved in the immunopathology of MS and a variety of medications such as beta interferons are applied to treat the disease. This study was conducted to evaluate the anti-inflammatory and immunomodulatory effects of sesame oil in combination with interferon beta-1a in MS treatment.

METHODS

Ninety-three MS patients were enrolled in the study. The patients were randomly divided into two groups. The control group (n = 39) received 30 μg/week of interferon beta-1a intra-muscularly. The sesame oil-treated group (n = 54) received interferon beta-1a the same as the control group with the addition of 0.5 ml/kg/day of oral sesame oil for 6 months.

RESULTS

After the 6-month study period, the interleukin (IL)-10 concentration in the sesame oil-treated group was significantly greater than that of the control group (p = 0.04). The concentrations of interferon-γ (IFN-γ), nitric oxide (NO), and tumor necrosis factor-α (TNF-α) in the sesame oil group after treatment were significantly less than those of the control group (p = 0.029, p = 0.0001, and p = 0.01, respectively). Lymphocyte proliferation in the sesame oil-treated group was significantly lower at the end of the study than at the beginning (p = 0.001).

CONCLUSION

Sesame oil, through a decrease in IFN-γ secretion and anti-inflammatory and anti-oxidant activities, may have beneficial effects for MS patients.

Research Advances of Germinal Matrix Hemorrhage: An Update Review

Germinal matrix hemorrhage (GMH) refers to bleeding that derives from the subependymal (or periventricular) germinal region of the premature brain. GMH can induce severe and irreversible damage attributing to the vulnerable structure of germinal matrix and deleterious circumstances. Molecular mechanisms remain obscure so far. In this review, we summarized the newest preclinical discoveries recent years about GMH to distill a deeper understanding of the neuropathology, and then discuss the potential diagnostic or therapeutic targets among these pathways. GMH studies mostly in recent 5 years were sorted out and the authors generalized the newest discoveries and ideas into four parts of this essay. Intrinsic fragile structure of preterm germinal matrix is the fundamental cause leading to GMH. Many molecules have been found effective in the pathophysiological courses. Some of these molecules like minocycline are suggested active to reduce the damage in animal GMH model. However, researchers are still trying to find efficient diagnostic methods and remedies that are available in preterm infants to rehabilitate or cure the sequent injury. Merits have been obtained in the last several years on molecular pathways of GMH, but more work is required to further unravel the whole pathophysiology.

Improvement by Human Oligodendrocyte Progenitor Cells of Neurobehavioral Disorders in an Experimental Model of Neonatal Periventricular Leukomalacia

The effects of human oligodendrocyte progenitor (F3.olig2) cells on improving neurobehavioral deficits were investigated in an experimental model of periventricular leukomalacia (PVL). Seven-day-old male rats were subjected to hypoxia-ischemia-lipopolysaccharide injection (HIL), and intracerebroventricularly transplanted with F3.olig2 (4 × 10⁵ cells/rat) once at post-natal day (PND) 10 or repeatedly at PND10, 17, 27, and 37. Neurobehavioral disorders were evaluated at PND14, 20, 30, and 40 via cylinder test, locomotor activity, and rotarod performance, and cognitive function was evaluated at PND41-45 through passive avoidance and Morris water-maze performances. F3.olig2 cells recovered the rate of use of the forelimb contralateral to the injured brain, improved locomotor activity, and restored rotarod performance of PVL animals; in addition, marked improvement of learning and memory function was seen. It was confirmed that transplanted F3·olig2 cells migrated to injured areas, matured to oligodendrocytes expressing myelin basic protein (MBP), and markedly attenuated the loss of host MBP in the corpus callosum. The results indicate that the transplanted F3.olig2 cells restored neurobehavioral functions by preventing axonal demyelination, and that human oligodendrocyte progenitor cells could be a candidate for cell therapy of perinatal hypoxic-ischemic and infectious brain injuries including PVL and cerebral palsy.

Efficient and Fast Differentiation of Human Neural Stem Cells from Human Embryonic Stem Cells for Cell Therapy

Stem cell-based therapies have been used for repairing damaged brain tissue and helping functional recovery after brain injury. Aberrance neurogenesis is related with brain injury, and multipotential neural stem cells from human embryonic stem (hES) cells provide a great promise for cell replacement therapies. Optimized protocols for neural differentiation are necessary to produce functional human neural stem cells (hNSCs) for cell therapy. However, the qualified procedure is scarce and detailed features of hNSCs originated from hES cells are still unclear. In this study, we developed a method to obtain hNSCs from hES cells, by which we could harvest abundant hNSCs in a relatively short time. Then, we examined the expression of pluripotent and multipotent marker genes through immunostaining and confirmed differentiation potential of the differentiated hNSCs. Furthermore, we analyzed the mitotic activity of these hNSCs. In this report, we provided comprehensive features of hNSCs and delivered the knowledge about how to obtain more high-quality hNSCs from hES cells which may help to accelerate the NSC-based therapies in brain injury treatment.

Methods of reactivation and reprogramming of neural stem cells for neural repair

Research on the biology of adult neural stem cells (NSCs) and induced NSCs (iNSCs), as well as NSC-based therapies for diseases in central nervous system (CNS) has started to generate the expectation that these cells may be used for treatments in CNS injuries or disorders. Recent technological progresses in both NSCs themselves and their derivatives have brought us closer to therapeutic applications. Adult neurogenesis presents in particular regions in mammal brain, known as neurogenic niches such as the dental gyrus (DG) in hippocampus and the subventricular zone (SVZ), within which adult NSCs usually stay for long periods out of the cell cycle, in G0. The reactivation of quiescent adult NSCs needs orchestrated interactions between the extrinsic stimulis from niches and the intrinsic factors involving transcription factors (TFs), signaling pathway, epigenetics, and metabolism to start an intracellular regulatory program, which promotes the quiescent NSCs exit G0 and reenter cell cycle. Extrinsic and intrinsic mechanisms that regulate adult NSCs are interconnected and feedback on one another. Since endogenous neurogenesis only happens in restricted regions and steadily fails with disease advances, interest has evolved to apply the iNSCs converted from somatic cells to treat CNS disorders, as is also promising and preferable. To overcome the limitation of viral-based reprogramming of iNSCs, bioactive small molecules (SM) have been explored to enhance the efficiency of iNSC reprogramming or even replace TFs, making the iNSCs more amenable to clinical application. Despite intense research efforts to translate the studies of adult and induced NSCs from the bench to bedside, vital troubles remain at several steps in these processes. In this review, we examine the present status, advancement, pitfalls, and potential of the two types of NSC technologies, focusing on each aspects of reactivation of quiescent adult NSC and reprogramming of iNSC from somatic cells, as well as on progresses in cell-based regenerative strategies for neural repair and criteria for successful therapeutic applications.

Effects of Noggin-Transfected Neural Stem Cells on Neural Functional Recovery and Underlying Mechanism in Rats with Cerebral Ischemia Reperfusion Injury

OBJECTIVE

To investigate neuroprotection of noggin-transfected neural stem cells (NSCs) against focal cerebral ischemia reperfusion injury (IRI) in rats.

METHODS

Eighty Wistar rats were randomly divided into the sham, IRI, NSCs, and noggin + NSCs groups. Noggin containing adenoviral vectors was transfected into rat NSCs. Rats were subjected to 2.0 hours middle cerebral artery occlusion and reperfusion 1.0 hour, followed by infusion into the lateral ventricles of NSCs alone, noggin-transfected NSCs, and saline at 3 days in the NSCs, noggin + NSCs, and sham groups, respectively. All rats were sacrificed on 1, 3, 7, and 28 days after transplantation; the colorimetric method was used to detect the levels of superoxide dismutase (SOD) and the malondialdehyde (MDA) content after the behavior capability determined. Western blot was performed for detecting the expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) proteins. The TUNEL-positive and BrdU/nestin double-positive cells were observed under a light microscope and quantitative analysis was performed by morphometric technique.

RESULTS

Noggin-transfected NSCs significantly decreased the infarct volume and improved the neurological scores. Noggin-transfected NSCs also reduced the percentage of apoptotic neurons and relieved neuronal morphological damage. Noggin-transfected NSC transplantation markedly decreased the MDA levels and increased the SOD activity, and simultaneously downregulated the BMP4 (bone morphogenesis protein), VEGF, and bFGF proteins.

CONCLUSIONS

The present study demonstrates that grafting NSCs modified by noggin gene provides better neuroprotection for cerebrovascular disease.

Therapeutic effects of human adipose tissue-derived stem cell (hADSC) transplantation on experimental autoimmune encephalomyelitis (EAE) mice

This study is to investigate the therapeutic effects of human adipose tissue-derived stem cell (hADSC) transplantation on experimental autoimmune encephalomyelitis (EAE) in mice. EAE mouse model was established by MOG35-55 immunization. Body weight and neurological function were assessed. H&E and LFB staining was performed to evaluate histopathological changes. Flow cytometry was used to detect Th17 and Treg cells. ELISA and real-time PCR were performed to determine transcription factor and pro-inflammatory cytokine levels. Transplantation of hADSCs significantly alleviated the body weight loss and neurological function impairment of EAE mice. Inflammatory cell infiltration and demyelination were significantly increased, which were relieved by hADSC transplantation. Moreover, the Th17 cells and the ROR-γt mRNA level were significantly elevated, while the Treg cells and the Foxp3 mRNA level were significantly declined, resulting in significantly increased Th17/Treg ratio. This was reversed by the transplantation of hADSCs. Furthermore, serum levels of IL-17A, IL-6, IL-23, and TGF-β, were significantly increased, which could be influenced by the hADSC transplantation. Transplantation of hADSCs alleviates the neurological function impairment and histological changes, and reduces the inflammatory cell infiltration and demyelination in EAE mice, which might be associated with the regulation of Th17/Treg balance.

Acupuncture Improves Cerebral Microenvironment in Mice with Alzheimer's Disease Treated with Hippocampal Neural Stem Cells

Transplantation with neural stem cells (NSCs) is a promising clinical therapy for Alzheimer's disease (AD). However, the final fate of grafted NSCs is mainly determined by the host microenvironment. Therefore, this study investigated the role of Sanjiao acupuncture in the NSCs-treated hippocampus of a mouse model, senescence-accelerated mouse prone 8 (SAMP8) using Western blot, real-time fluorescent PCR, and immunofluorescence techniques. Meanwhile, we developed a co-culture model of hippocampal tissue specimens and NSCs in vitro, to observe the effects of acupuncture on survival, proliferation and differentiation of grafted NSCs using flow cytometry. Results showed that acupuncture pre- and post-NSCs transplantation significantly improved senescence-induced cognitive dysfunction (P < 0.05); upregulated the expression of basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), and brain-derived neurotrophic factor (BDNF) (P < 0.05); and also increased the count of neuron-specific nuclear protein (NeuN)- and glial fibrillary acidic protein (GFAP)-positive cells (P < 0.05). Therapeutic acupuncture may regulate the cytokine levels associated with survival, proliferation, and differentiation of NSCs in hippocampal microenvironment, to promote the repair of damaged cells, resulting in improved cognitive performance in mice.