Cytokines including tumor necrosis factor, interleukins, interferons, and chemokines are abundantly produced in various diseases. As pleiotropic factors, cytokines are involved in nearly every aspect of cellular funct...Cytokines including tumor necrosis factor, interleukins, interferons, and chemokines are abundantly produced in various diseases. As pleiotropic factors, cytokines are involved in nearly every aspect of cellular functions such as migration, survival, proliferation, and differentiation. Oligodendrocytes are the myelin-forming cells in the central nervous system and play critical roles in the conduction of action potentials, supply of metabolic components for axons, and other functions. Emerging evidence suggests that both oligodendrocytes and oligodendrocyte precursor cells are vulnerable to cytokines released under pathological conditions. This review mainly summarizes the effects of cytokines on oligodendrocyte lineage cells in central nervous system diseases. A comprehensive understanding of the effects of cytokines on oligodendrocyte lineage cells contributes to our understanding of central nervous system diseases and offers insights into treatment strategies.展开更多
BACKGROUND Cases of myelin oligodendrocyte glycoprotein(MOG)antibody-related disease have a history of coronavirus disease 2019 infection or its vaccination before disease onset.Severe acute respiratory syndrome virus...BACKGROUND Cases of myelin oligodendrocyte glycoprotein(MOG)antibody-related disease have a history of coronavirus disease 2019 infection or its vaccination before disease onset.Severe acute respiratory syndrome virus 2(SARS-CoV-2)infection has been considered to be a trigger of central nervous system autoimmune diseases.CASE SUMMARY Here we report a 20-year male with MOG-associated transverse myelitis after a SARS-CoV-2 infection.The patient received a near-complete recovery after standard immunological treatments.CONCLUSION Attention should be paid to the evaluation of typical or atypical neurological symptoms that may be triggered by SARS-CoV-2 infection.展开更多
General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells.Oligodendrocytes perform essential roles in the central nervous system,including myelin sheath for...General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells.Oligodendrocytes perform essential roles in the central nervous system,including myelin sheath formation,axonal metabolism,and neuroplasticity regulation.They are particularly vulnerable to the effects of general anesthetic agents resulting in impaired proliferation,differentiation,and apoptosis.Neurologists are increasingly interested in the effects of general anesthetic agents on oligodendrocytes.These agents not only act on the surface receptors of oligodendrocytes to elicit neuroinflammation through modulation of signaling pathways,but also disrupt metabolic processes and alter the expression of genes involved in oligodendrocyte development and function.In this review,we summarize the effects of general anesthetic agents on oligodendrocytes.We anticipate that future research will continue to explore these effects and develop strategies to decrease the incidence of adverse reactions associated with the use of general anesthetic agents.展开更多
Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to remyelination.Failure of remyelination due to oligodendrocyte progenitor cell death can result in severe n...Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to remyelination.Failure of remyelination due to oligodendrocyte progenitor cell death can result in severe nerve damage.Ferroptosis is an iron-dependent form of regulated cell death caused by membrane rupture induced by lipid peroxidation,and plays an important role in the pathological process of ischemic stroke.However,there are few studies on oligodendrocyte progenitor cell ferroptosis.We analyzed transcriptome sequencing data from GEO databases and identified a role of ferroptosis in oligodendrocyte progenitor cell death and myelin injury after cerebral ischemia.Bioinformatics analysis suggested that perilipin-2(PLIN2)was involved in oligodendrocyte progenitor cell ferroptosis.PLIN2 is a lipid storage protein and a marker of hypoxia-sensitive lipid droplet accumulation.For further investigation,we established a mouse model of cerebral ischemia/reperfusion.We found significant myelin damage after cerebral ischemia,as well as oligodendrocyte progenitor cell death and increased lipid peroxidation levels around the infarct area.The ferroptosis inhibitor,ferrostatin-1,rescued oligodendrocyte progenitor cell death and subsequent myelin injury.We also found increased PLIN2 levels in the peri-infarct area that co-localized with oligodendrocyte progenitor cells.Plin2 knockdown rescued demyelination and improved neurological deficits.Our findings suggest that targeting PLIN2 to regulate oligodendrocyte progenitor cell ferroptosis may be a potential therapeutic strategy for rescuing myelin damage after cerebral ischemia.展开更多
BACKGROUND Gliomas are the most common primary central nervous system neoplasm.Despite recent advances in the diagnosis and treatment of gliomas,patient prognosis remains dismal.Therefore,it is imperative to identify ...BACKGROUND Gliomas are the most common primary central nervous system neoplasm.Despite recent advances in the diagnosis and treatment of gliomas,patient prognosis remains dismal.Therefore,it is imperative to identify novel diagnostic biomarkers and therapeutic targets of glioma to effectively improve treatment outcomes.AIM To investigate the association between oligodendrocyte transcription factor 2(Olig2)expression and the outcomes of glioma patients.METHODS The PubMed,Embase,Cochrane Library,and China National Knowledge Infrastructure databases were searched for studies(published up to October 2023)that investigated the relationship between Olig2 expression and prognosis of glioma patients.The quality of the studies was assessed using the Newcastle Ottawa Scale.Data analyses were performed using Stata Version 12.0 software.RESULTS A total of 1205 glioma patients from six studies were included in the metaanalysis.High Olig2 expression was associated with better outcomes in glioma patients[hazard ratio(HR):0.81;95%(confidence interval)CI:0.51-1.27;P=0.000].Furthermore,the results of subgroup meta-analysis showed that high expression of Olig2 was associated with poor overall survival in European patients(HR:1.34;95%CI:0.79-2.27)and better prognosis in Asian patients(HR:0.43;95%CI:0.22-0.84).The sensitivity analysis showed that no single study had a significant effect on pooled HR,and there was also no indication of publication bias according to the Egger’s and Begger’s P value test or funnel plot test.CONCLUSION High Olig2 expression may have a positive impact on the prognosis of glioma patients,and should be investigated further as a prognostic biomarker and therapeutic target for glioma.展开更多
Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ<sub>1-42</sub>-induced oligodendrocytes (OL) damage. ...Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ<sub>1-42</sub>-induced oligodendrocytes (OL) damage. Methods: Immunofluorescence was used for the detection of myelin-associated glycoprotein (MAG), a characteristic protein of rat oligodendrocytes (OLN-93 cells). To evaluate the potential protective effects of SSFs on OLN-93 cells injured by Aβ<sub>1-42</sub>, an injury model was established by subjecting OLN-93 cells to Aβ<sub>1-42</sub> exposed. Cell morphology was examined using an inverted microscope, while cell viability was assessed using the colorimetric method of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Additionally, lactate dehydrogenase (LDH) was measured using the pyruvic acid reduction assay. The Ginkgo biloba leaf extract (GBE) injection was used as a positive control. Results: A total of >95% of the MAG immunofluorescence-positive cells were identified as oligodendrocytes. Gradually increasing concentrations of SSFs impaired the cells, and the maximum nondetrimental dose for OLN-93 cells was 75 mg/L. This study assessed the effects of SSFs on OLN-93 cells damaged by Aβ<sub>1-42</sub>. The results indicated that SSFs significantly improved OLN-93 cell morphological abnormal changes, increased the OLN-93 cell survival rate, and reduced LDH release. Conclusion: SSFs can alleviate Aβ<sub>1-42</sub>-induced damage of OL.展开更多
The extracellular matrix surrounding oligodendrocytes plays an important role during myelination and remyelination in the brain.In many cases,the microenvironment surrounding demyelination lesions contains inhibitory ...The extracellular matrix surrounding oligodendrocytes plays an important role during myelination and remyelination in the brain.In many cases,the microenvironment surrounding demyelination lesions contains inhibitory molecules,which lead to repair failure.Accordingly,blocking the activity of these inhibitory factors in the extracellular matrix should lead to more successful remyelination.In the central nervous system,oligodendrocytes form the myelin sheath.We performed primary cell culture and found that a natural increase in fibronectin promoted the proliferation of oligodendrocyte progenitors during the initial stage of remyelination while inhibiting oligodendrocyte differentiation.Poly-L-ornithine blocked these inhibitory effects without compromising fibronectin’s pro-proliferation function.Experiments showed that poly-L-ornithine activated the Erk1/2 signaling pathway that is necessary in the early stages of differentiation,as well as PI3K signaling pathways that are needed in the mid-late stages.When poly-L-ornithine was tested in a lysolecithin-induced animal model of focal demyelination,it enhanced myelin regeneration and promoted motor function recovery.These findings suggest that poly-L-ornithine has the potential to be a treatment option for clinical myelin sheath injury.展开更多
Oligodencrocytes(OLs) are the main glial cells of the central nervous system involved in myelination of axons. In multiple sclerosis(MS), there is an imbalance between demyelination and remyelination processes, th...Oligodencrocytes(OLs) are the main glial cells of the central nervous system involved in myelination of axons. In multiple sclerosis(MS), there is an imbalance between demyelination and remyelination processes, the last one performed by oligodendrocyte progenitor cells(OPCs) and OLs, resulting into a permanent demyelination, axonal damage and neuronal loss. In MS lesions, astrocytes and microglias play an important part in permeabilization of blood-brain barrier and initiation of OPCs proliferation. Migration and differentiation of OPCs are influenced by various factors and the process is finalized by insufficient acummulation of OLs into the MS lesion. In relation to all these processes, the author will discuss the potential targets for remyelination strategies.展开更多
The pathology of fetal alcohol syndrome and the less severe fetal alcohol spectrum disorders includes brain dysmyelination.Recent studies have shed light on the molecular mechanisms underlying these white matter abnor...The pathology of fetal alcohol syndrome and the less severe fetal alcohol spectrum disorders includes brain dysmyelination.Recent studies have shed light on the molecular mechanisms underlying these white matter abnormalities.Rodent models of fetal alcohol syndrome and human studies have shown suppressed oligodendrocyte differentiation and apoptosis of oligodendrocyte precursor cells.Ethanol exposure led to reduced expression of myelin basic protein and delayed myelin basic protein expression in rat and mouse models of fetal alcohol syndrome and in human histopathological specimens.Several studies have reported increased expression of many chemokines in dysmyelinating disorders in central nervous system,including multiple sclerosis and fetal alcohol syndrome.Acute ethanol exposure reduced levels of the neuroprotective insulin-like growth factor-1 in fetal and maternal sheep and in human fetal brain tissues,while ethanol increased the expression of tumor necrosis factor α in mouse and human neurons.White matter lesions have been induced in the developing sheep brain by alcohol exposure in early gestation.Rat fetal alcohol syndrome models have shown reduced axon diameters,with thinner myelin sheaths,as well as reduced numbers of oligodendrocytes,which were also morphologically aberrant oligodendrocytes.Expressions of markers for mature myelination,including myelin basic protein,also were reduced.The accumulating knowledge concerning the mechanisms of ethanol-induced dysmyelination could lead to the development of strategies to prevent dysmyelination in children exposed to ethanol during fetal development.Future studies using fetal oligodendrocyte-and oligodendrocyte precursor cell-derived exosomes isolated from the mother's blood may identify biomarkers for fetal alcohol syndrome and even implicate epigenetic changes in early development that affect oligodendrocyte precursor cell and oligodendrocyte function in adulthood.By combining various imaging modalities with molecular studies,it may be possible to determine which fetuses are at risk and to intervene therapeutically early in the pregnancy.展开更多
Oligodendrocyte lineage cells(OL-lineage cells)are a cell population that are crucial for mammalian central nervous system(CNS)myelination.OL-lineage cells go through developmental stages,initially differentiating int...Oligodendrocyte lineage cells(OL-lineage cells)are a cell population that are crucial for mammalian central nervous system(CNS)myelination.OL-lineage cells go through developmental stages,initially differentiating into oligodendrocyte precursor cells(OPCs),before becoming immature oligodendrocytes,then mature oligodendrocytes(OLs).While the main function of cell lineage is in myelin formation,and increasing number of studies have turned to explore the immunological characteristics of these cells.Initially,these studies focused on discovering how OPCs and OLs are affected by the immune system,and then,how these immunological changes influence the myelination process.However,recent studies have uncovered another feature of OL-lineage cells in our immune systems.It would appear that OL-lineage cells also express immunological factors such as cytokines and chemokines in response to immune activation,and the expression of these factors changes under various pathologic conditions.Evidence suggests that OL-lineage cells actually modulate immune functions.Indeed,OL-lineage cells appear to play both"victim"and"agent"in the CNS which raises a number of questions.Here,we summarize immunologic changes in OL-lineage cells and their effects,as well as consider OL-lineage cell changes which influence immune cells under pathological conditions.We also describe some of the underlying mechanisms of these changes and their effects.Finally,we describe several studies which use OL-lineage cells as immunotherapeutic targets for demyelination diseases.展开更多
Oligodendrocyte lineage gene-1 expressed in oligodendrocytes may trigger the repair of neuronal myelin impairment, and play a crucial role in myelin repair. Hypoxia-inducible factor la, a transcription factor, is of g...Oligodendrocyte lineage gene-1 expressed in oligodendrocytes may trigger the repair of neuronal myelin impairment, and play a crucial role in myelin repair. Hypoxia-inducible factor la, a transcription factor, is of great significance in premature infants with hypoxic-ischemic brain damage There is little evidence of direct regulatory effects of hypoxia-inducible factor le on oligodendrocyte lineage gene-l. In this study, brain slices of Sprague-Dawley rats were cultured and subjected to oxygen-glucose deprivation. Then, slices were transfected with hypoxia-inducible factor la or oligodendrocyte lineage gene-1. The expression levels of hypoxia-inducible factor la and oligodendrocyte lineage gene-1 were significantly up-regulated in rat brains prior to transfection, as detected by immunohistochemical staining. Eight hours after transfection of slices with hypoxia-inducible factor la, oligodendrocyte lineage gene-1 expression was upregulated, and reached a peak 24 hours after transfection. Oligodendrocyte lineage gene-1 transfection induced no significant differences in hypoxia-inducible factor la levels in rat brain tissues with oxygen-glucose deprivation. These experimental findings indicate that hypoxia-inducible factor la can regulate oligodendrocyte lineage gene-1 expression in hypoxic brain tissue, thus repairing the neural impairment.展开更多
To examine the expression profiles of oligodendrocyte transcription factors 1 and 2 (Oligl and Olig2) and the interaction between these two proteins, Oligl was transfected into the lateral ventricles of neonatal rat...To examine the expression profiles of oligodendrocyte transcription factors 1 and 2 (Oligl and Olig2) and the interaction between these two proteins, Oligl was transfected into the lateral ventricles of neonatal rats subjected to hypoxia. Immunohistochemistry demonstrated that Olig2 was expressed throughout the nuclei in the brain, and expression increased at 3 days following hypoxia and was higher than levels at 7 days following Ad5-Oligl transfection. Western blot revealed that Oligl and Olig2 expression increased in Oligl-transfected brain cells 3 days after hypoxia, but Oligl and Olig2 expression decreased at 7 days. These results indicate that Oligl overexpression enhances Olig2 expression in brain tissues of hypoxia rats.展开更多
Oligodendrocyte-formed myelin sheaths allow fast synaptic transmission in the brain and their degeneration leads to demyelinating diseases such as multiple sclerosis. Remyelination requires the differentiation of olig...Oligodendrocyte-formed myelin sheaths allow fast synaptic transmission in the brain and their degeneration leads to demyelinating diseases such as multiple sclerosis. Remyelination requires the differentiation of oligodendrocyte progenitor cells into mature oligodendrocytes but, in chronic neurodegenerative disorders, remyelination fails due to adverse environment. Therefore, a strategy to prompt oligodendrocyte progenitor cell differentiation towards myelinating oligodendrocytes is required. The neuromodulator adenosine, and its receptors(A1, A(2A), A(2B) and A3 receptors: A1R, A(2A)R, A(2B)R and A3R), are crucial mediators in remyelination processes. It is known that A1Rs facilitate oligodendrocyte progenitor cell maturation and migration whereas the A3Rs initiates apoptosis in oligodendrocyte progenitor cells. Our group of research contributed to the field by demonstrating that A(2A)R and A(2B)R inhibit oligodendrocyte progenitor cell maturation by reducing voltage-dependent K^+ currents necessary for cell differentiation. The present review summarizes the possible role of adenosine receptor ligands as potential therapeutic targets in demyelinating pathologies such as multiple sclerosis.展开更多
Our previous studies showed that ferroptosis plays an important role in the acute and subacute stages of spinal cord injury.High intracellular iron levels and low glutathione levels make oligodendrocytes vulnerable to...Our previous studies showed that ferroptosis plays an important role in the acute and subacute stages of spinal cord injury.High intracellular iron levels and low glutathione levels make oligodendrocytes vulnerable to cell death after central nervous system trauma.In this study,we established an oligodendrocyte(OLN-93 cell line)model of ferroptosis induced by RSL-3,an inhibitor of glutathione peroxidase 4(GPX4).RSL-3 significantly increased intracellular concentrations of reactive oxygen species and malondialdehyde.RSL-3 also inhibited the main antiferroptosis pathway,i.e.,SLC7A11/glutathione/glutathione peroxidase 4(xCT/GSH/GPX4),and downregulated acyl-coenzyme A synthetase long chain family member 4.Furthermore,we evaluated the ability of several compounds to rescue oligodendrocytes from ferroptosis.Liproxstatin-1 was more potent than edaravone or deferoxamine.Liproxstatin-1 not only inhibited mitochondrial lipid peroxidation,but also restored the expression of GSH,GPX4 and ferroptosis suppressor protein 1.These findings suggest that GPX4 inhibition induces ferroptosis in oligodendrocytes,and that liproxstatin-1 is a potent inhibitor of ferroptosis.Therefore,liproxstatin-1 may be a promising drug for the treatment of central nervous system diseases.展开更多
Iron is an essential trophic element that is required for cell viability and differentiation, especially in oligodendrocytes, which consume relatively high rates of energy to produce myelin. Multiple iron metabolism p...Iron is an essential trophic element that is required for cell viability and differentiation, especially in oligodendrocytes, which consume relatively high rates of energy to produce myelin. Multiple iron metabolism proteins are expressed in the brain including transferrin receptor and ferritin-H. However, it is still unknown whether they are developmentally regulated in oligodendrocyte lineage cells for myelination. Here, using an in vitro cultured differentiation model of oligodendrocytes, we found that both transferrin receptor and ferritin-H are significantly upregulated during oligodendrocyte maturation, implying the essential role of iron in the development of oligodendrocytes. Additional different doses of Fe3+ in the cultured medium did not affect oligodendrocyte precursor cell maturation or ferritin-H expression but decreased the expression of the transferrin receptor. These results indicate that upregulation of both transferrin receptor and ferritin-H contributes to maturation and myelination of oligodendrocyte precursor cells.展开更多
Human umbilical mesenchymal stem cells from Wharton's jelly of the umbilical cord were induced to differentiate into oligodendrocyte precursor-like cells in vitro. Oligodendrocyte precursor cells were transplanted in...Human umbilical mesenchymal stem cells from Wharton's jelly of the umbilical cord were induced to differentiate into oligodendrocyte precursor-like cells in vitro. Oligodendrocyte precursor cells were transplanted into contused rat spinal cords. Immunofluorescence double staining indicated that transplanted cells survived in injured spinal cord, and differentiated into mature and immature oligodendrocyte precursor cells. Biotinylated dextran amine tracing results showed that cell transplantation promoted a higher density of the corticospinal tract in the central and caudal parts of the injured spinal cord. Luxol fast blue and toluidine blue staining showed that the volume of residual myelin was significantly increased at 1 and 2 mm rostral and caudal to the lesion epicenter after cell transplantation. Furthermore, immunofluorescence staining verified that the newly regenerated myelin sheath was derived from the central nervous system. Basso, Beattie and Bresnahan testing showed an evident behavioral recovery. These results suggest that human umbilical mesenchymal stem cell-derived oligodendrocyte precursor cells promote the regeneration of spinal axons and myelin sheaths.展开更多
Oligodendrocyte lineage gene 1 plays a key role in hypoxic-ischemic brain damage and myelin repair, miRNA-9 is involved in the occurrence of many related neurological disorders. Bioin- formatics analysis demonstrated ...Oligodendrocyte lineage gene 1 plays a key role in hypoxic-ischemic brain damage and myelin repair, miRNA-9 is involved in the occurrence of many related neurological disorders. Bioin- formatics analysis demonstrated that miRNA-9 complementarily, but incompletely, bound oligodendrocyte lineage gene 1, but whether miRNA-9 regulates oligodendrocyte lineage gene 1 remains poorly understood. Whole brain slices of 3-day-old Sprague-Dawley rats were cultured and divided into four groups: control group; oxygen-glucose deprivation group (treatment with 8% O2 + 92% N2 and sugar-free medium for 60 minutes); transfection control group (after oxygen and glucose deprivation for 60 minutes, transfected with control plasmid) and miRNA-9 transfection group (after oxygen and glucose deprivation for 60 minutes, transfected with miRNA-9 plasmid). From the third day of transfection, and with increasing culture days, oligodendrocyte lineage gene 1 expression increased in each group, peaked at 14 days, and then decreased at 21 days. Real-time quantitative PCR results, however, demonstrated that oligoden- drocyte lineage gene 1 expression was lower in the miRNA-9 transfection group than that in the transfection control group at 1, 3, 7, 14, 21 and 28 days after transfection. Results suggested that miRNA-9 possibly negatively regulated oligodendrocyte lineage gene 1 in brain tissues during hypoxic-ischemic brain damage.展开更多
A contusive model of spinal cord injury at spinal segment T8-9 was established in rats. Huantiao (GB30) and Huatuojiaji (Ex-B05) were punctured with needles, and endogenous neural stem cells were labeled with 5-br...A contusive model of spinal cord injury at spinal segment T8-9 was established in rats. Huantiao (GB30) and Huatuojiaji (Ex-B05) were punctured with needles, and endogenous neural stem cells were labeled with 5-bromo-2'-deoxyuridine (BrdU) and NG2. Double immunofluorescence staining showed that electroacupuncture markedly increased the numbers of BrdU+/NG2+cells at spinal cord tissue 15 mm away from the injury center in the rostral and caudal directions. The results suggest that electroacupuncture promotes the proliferation of endogenous neural stem cells and oligodendrocytes in rats with spinal cord injury.展开更多
Periventricular white matter injury (PWMI)is very common in survivors of premature birth,and the final outcomes are a reduction in myelinated neurons leading to white matter hypomyelination.How and (or) why the oligod...Periventricular white matter injury (PWMI)is very common in survivors of premature birth,and the final outcomes are a reduction in myelinated neurons leading to white matter hypomyelination.How and (or) why the oligodendrocyte lineage develops abnormally and myelination is reduced is a hot topic in the field.This study focuses on the effect of intrauterine inflammation on the proliferation of oligodendrocyte lineage cells and the underlying mechanisms.Lipopolysaccharide (LPS)(300μg/kg)was intraperitoneally injected into pregnant Sprague-Dawley rats at embryonic days 19 and 20 to establish a rat model of intrauterine infection-induced white matter injury.Corpus callosum tissues were collected at postnatal day 14(P14)to quantify the number of oligodendrocytes,the number and proliferation of oligodendrocyte precursor cells (OPCs), and the expression of myelin proteins (MBP and PLP).Furthermore,the expression of Writ and Notch signaling-related proteins was analyzed.The results showed that the number of oligodendrocytes in the corpus callosum tissues of LPS-treated rats was reduced,and the expression levels of myelinating proteins were down-regulated.Further analysis showed that the Notch signaling pathway was down-regulated in the LPS-treated group.These results indicate that intrauterine LPS may inhibit the proliferation of OPCs by down-regulating the Notch rather than the Writ signaling pathway,leading to hypomyelination of white matter.展开更多
The consequences of neonatal white matter injury are devastating and represent a major societal problem as currently there is no cure.Prematurity,low weight birth and maternal pre-natal infection are the most frequent...The consequences of neonatal white matter injury are devastating and represent a major societal problem as currently there is no cure.Prematurity,low weight birth and maternal pre-natal infection are the most frequent causes of acquired myelin deficiency in the human neonate leading to cerebral palsy and cognitive impairment.In the developing brain,oligodendrocyte(OL)maturation occurs perinatally,and immature OLs are particularly vulnerable.Cell replacement therapy is often considered a viable option to replace progenitors that die due to glutamate excitotoxicity.We previously reported directed specification and mobilization of endogenous committed and uncommitted neural progenitors by the combination of transferrin and insulin growth factor 1(TSC1).Here,considering cell replacement and integration as therapeutic goals,we examined if OL progenitors(OLPs)grafted into the brain parenchyma of mice that were subjected to an excitotoxic insult could rescue white matter injury.For that purpose,we used a well-established model of glutamate excitotoxic injury.Four-day-old mice received a single intraparenchymal injection of the glutamate receptor agonist N-methyl-D-aspartate alone or in conjunction with TSC1 in the presence or absence of OLPs grafted into the brain parenchyma.Energetics and expression of stress proteins and OL developmental specific markers were examined.A comparison of the proteomic profile per treatment was also ascertained.We found that OLPs did not survive in the excitotoxic environment when grafted alone.In contrast,when combined with TSC1,survival and integration of grafted OLPs was observed.Further,energy metabolism in OLPs was significantly increased by N-methyl-D-aspartate and modulated by TSC1.The proteomic profile after the various treatments showed elevated ubiquitination and stress/heat shock protein 90 in response to N-methyl-D-aspartate.These changes were reversed in the presence of TSC1 and ubiquitination was decreased.The results obtained in this pre-clinical study indicate that the use of a combinatorial intervention including both trophic support and healthy OLPs constitutes a promising approach for long-term survival and successful graft integration.We established optimal conditioning of the host brain environment to promote long-term survival and integration of grafted OLPs into an inflamed neonate host brain.Experimental procedures were performed under the United States Public Health Service Guide for the Care and Use of Laboratory Animals and were approved by the Institutional Animal Care Committee at(UCLA)(ARC#1992-034-61)on July 1,2010.展开更多
基金supported by the Natural Science Foundation of Zhejiang Province,No.LQ23C090003 (to CZ)the Major Project on Brain Science and Analog Brain Research of Ministry of Science and Technology of China,No.2022ZD0204701 (to MQ)the National Natural Science Foundation of China,No.32170969 (to MQ)。
文摘Cytokines including tumor necrosis factor, interleukins, interferons, and chemokines are abundantly produced in various diseases. As pleiotropic factors, cytokines are involved in nearly every aspect of cellular functions such as migration, survival, proliferation, and differentiation. Oligodendrocytes are the myelin-forming cells in the central nervous system and play critical roles in the conduction of action potentials, supply of metabolic components for axons, and other functions. Emerging evidence suggests that both oligodendrocytes and oligodendrocyte precursor cells are vulnerable to cytokines released under pathological conditions. This review mainly summarizes the effects of cytokines on oligodendrocyte lineage cells in central nervous system diseases. A comprehensive understanding of the effects of cytokines on oligodendrocyte lineage cells contributes to our understanding of central nervous system diseases and offers insights into treatment strategies.
基金Supported by the Shenzhen University Teaching Reform Fund,No.JG2023166the Shenzhen Science and Technology Innovation Commission Fund,No.JCYJ2022081802810022the Shenzhen Science and Technology Innovation Commission Basic Research Key Projects Fund,No.JCYJ20210324115800003.
文摘BACKGROUND Cases of myelin oligodendrocyte glycoprotein(MOG)antibody-related disease have a history of coronavirus disease 2019 infection or its vaccination before disease onset.Severe acute respiratory syndrome virus 2(SARS-CoV-2)infection has been considered to be a trigger of central nervous system autoimmune diseases.CASE SUMMARY Here we report a 20-year male with MOG-associated transverse myelitis after a SARS-CoV-2 infection.The patient received a near-complete recovery after standard immunological treatments.CONCLUSION Attention should be paid to the evaluation of typical or atypical neurological symptoms that may be triggered by SARS-CoV-2 infection.
基金supported by the Natural Science Foundation of Zhejiang Province(LZ22H090002,2014C33170)National Natural Science Foundation of China(82171260,81641042,81471240)。
文摘General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells.Oligodendrocytes perform essential roles in the central nervous system,including myelin sheath formation,axonal metabolism,and neuroplasticity regulation.They are particularly vulnerable to the effects of general anesthetic agents resulting in impaired proliferation,differentiation,and apoptosis.Neurologists are increasingly interested in the effects of general anesthetic agents on oligodendrocytes.These agents not only act on the surface receptors of oligodendrocytes to elicit neuroinflammation through modulation of signaling pathways,but also disrupt metabolic processes and alter the expression of genes involved in oligodendrocyte development and function.In this review,we summarize the effects of general anesthetic agents on oligodendrocytes.We anticipate that future research will continue to explore these effects and develop strategies to decrease the incidence of adverse reactions associated with the use of general anesthetic agents.
基金supported by the National Natural Science Foundation of China,Nos.82071307(to HL),82271362(to HL),82171294(to JW),82371303(to JW),and 82301460(to PX)the Natural Science Foundation of Jiangsu Province,No.BK20211552(to HL)+1 种基金Suzhou Medical Technology Innovation Project-Clinical Frontier,No.SKY2022002(to ZY)the Science and Education Foundation for Health of Suzhou for Youth,No.KJXW2023001(to XL)。
文摘Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to remyelination.Failure of remyelination due to oligodendrocyte progenitor cell death can result in severe nerve damage.Ferroptosis is an iron-dependent form of regulated cell death caused by membrane rupture induced by lipid peroxidation,and plays an important role in the pathological process of ischemic stroke.However,there are few studies on oligodendrocyte progenitor cell ferroptosis.We analyzed transcriptome sequencing data from GEO databases and identified a role of ferroptosis in oligodendrocyte progenitor cell death and myelin injury after cerebral ischemia.Bioinformatics analysis suggested that perilipin-2(PLIN2)was involved in oligodendrocyte progenitor cell ferroptosis.PLIN2 is a lipid storage protein and a marker of hypoxia-sensitive lipid droplet accumulation.For further investigation,we established a mouse model of cerebral ischemia/reperfusion.We found significant myelin damage after cerebral ischemia,as well as oligodendrocyte progenitor cell death and increased lipid peroxidation levels around the infarct area.The ferroptosis inhibitor,ferrostatin-1,rescued oligodendrocyte progenitor cell death and subsequent myelin injury.We also found increased PLIN2 levels in the peri-infarct area that co-localized with oligodendrocyte progenitor cells.Plin2 knockdown rescued demyelination and improved neurological deficits.Our findings suggest that targeting PLIN2 to regulate oligodendrocyte progenitor cell ferroptosis may be a potential therapeutic strategy for rescuing myelin damage after cerebral ischemia.
文摘BACKGROUND Gliomas are the most common primary central nervous system neoplasm.Despite recent advances in the diagnosis and treatment of gliomas,patient prognosis remains dismal.Therefore,it is imperative to identify novel diagnostic biomarkers and therapeutic targets of glioma to effectively improve treatment outcomes.AIM To investigate the association between oligodendrocyte transcription factor 2(Olig2)expression and the outcomes of glioma patients.METHODS The PubMed,Embase,Cochrane Library,and China National Knowledge Infrastructure databases were searched for studies(published up to October 2023)that investigated the relationship between Olig2 expression and prognosis of glioma patients.The quality of the studies was assessed using the Newcastle Ottawa Scale.Data analyses were performed using Stata Version 12.0 software.RESULTS A total of 1205 glioma patients from six studies were included in the metaanalysis.High Olig2 expression was associated with better outcomes in glioma patients[hazard ratio(HR):0.81;95%(confidence interval)CI:0.51-1.27;P=0.000].Furthermore,the results of subgroup meta-analysis showed that high expression of Olig2 was associated with poor overall survival in European patients(HR:1.34;95%CI:0.79-2.27)and better prognosis in Asian patients(HR:0.43;95%CI:0.22-0.84).The sensitivity analysis showed that no single study had a significant effect on pooled HR,and there was also no indication of publication bias according to the Egger’s and Begger’s P value test or funnel plot test.CONCLUSION High Olig2 expression may have a positive impact on the prognosis of glioma patients,and should be investigated further as a prognostic biomarker and therapeutic target for glioma.
文摘Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ<sub>1-42</sub>-induced oligodendrocytes (OL) damage. Methods: Immunofluorescence was used for the detection of myelin-associated glycoprotein (MAG), a characteristic protein of rat oligodendrocytes (OLN-93 cells). To evaluate the potential protective effects of SSFs on OLN-93 cells injured by Aβ<sub>1-42</sub>, an injury model was established by subjecting OLN-93 cells to Aβ<sub>1-42</sub> exposed. Cell morphology was examined using an inverted microscope, while cell viability was assessed using the colorimetric method of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Additionally, lactate dehydrogenase (LDH) was measured using the pyruvic acid reduction assay. The Ginkgo biloba leaf extract (GBE) injection was used as a positive control. Results: A total of >95% of the MAG immunofluorescence-positive cells were identified as oligodendrocytes. Gradually increasing concentrations of SSFs impaired the cells, and the maximum nondetrimental dose for OLN-93 cells was 75 mg/L. This study assessed the effects of SSFs on OLN-93 cells damaged by Aβ<sub>1-42</sub>. The results indicated that SSFs significantly improved OLN-93 cell morphological abnormal changes, increased the OLN-93 cell survival rate, and reduced LDH release. Conclusion: SSFs can alleviate Aβ<sub>1-42</sub>-induced damage of OL.
基金supported by the National Nature Science Foundation of China,Nos.81371338(to HF)and 82071369(PPY)。
文摘The extracellular matrix surrounding oligodendrocytes plays an important role during myelination and remyelination in the brain.In many cases,the microenvironment surrounding demyelination lesions contains inhibitory molecules,which lead to repair failure.Accordingly,blocking the activity of these inhibitory factors in the extracellular matrix should lead to more successful remyelination.In the central nervous system,oligodendrocytes form the myelin sheath.We performed primary cell culture and found that a natural increase in fibronectin promoted the proliferation of oligodendrocyte progenitors during the initial stage of remyelination while inhibiting oligodendrocyte differentiation.Poly-L-ornithine blocked these inhibitory effects without compromising fibronectin’s pro-proliferation function.Experiments showed that poly-L-ornithine activated the Erk1/2 signaling pathway that is necessary in the early stages of differentiation,as well as PI3K signaling pathways that are needed in the mid-late stages.When poly-L-ornithine was tested in a lysolecithin-induced animal model of focal demyelination,it enhanced myelin regeneration and promoted motor function recovery.These findings suggest that poly-L-ornithine has the potential to be a treatment option for clinical myelin sheath injury.
文摘Oligodencrocytes(OLs) are the main glial cells of the central nervous system involved in myelination of axons. In multiple sclerosis(MS), there is an imbalance between demyelination and remyelination processes, the last one performed by oligodendrocyte progenitor cells(OPCs) and OLs, resulting into a permanent demyelination, axonal damage and neuronal loss. In MS lesions, astrocytes and microglias play an important part in permeabilization of blood-brain barrier and initiation of OPCs proliferation. Migration and differentiation of OPCs are influenced by various factors and the process is finalized by insufficient acummulation of OLs into the MS lesion. In relation to all these processes, the author will discuss the potential targets for remyelination strategies.
基金supported by NIH grants R01NS97846,R01NS097846-02S1 and R01NS092876 awarded to MESShriners research grant SHC-85400 awarded to MESUSA Pennsylvania State Department grant Project 10:420491-04400-02 to ND。
文摘The pathology of fetal alcohol syndrome and the less severe fetal alcohol spectrum disorders includes brain dysmyelination.Recent studies have shed light on the molecular mechanisms underlying these white matter abnormalities.Rodent models of fetal alcohol syndrome and human studies have shown suppressed oligodendrocyte differentiation and apoptosis of oligodendrocyte precursor cells.Ethanol exposure led to reduced expression of myelin basic protein and delayed myelin basic protein expression in rat and mouse models of fetal alcohol syndrome and in human histopathological specimens.Several studies have reported increased expression of many chemokines in dysmyelinating disorders in central nervous system,including multiple sclerosis and fetal alcohol syndrome.Acute ethanol exposure reduced levels of the neuroprotective insulin-like growth factor-1 in fetal and maternal sheep and in human fetal brain tissues,while ethanol increased the expression of tumor necrosis factor α in mouse and human neurons.White matter lesions have been induced in the developing sheep brain by alcohol exposure in early gestation.Rat fetal alcohol syndrome models have shown reduced axon diameters,with thinner myelin sheaths,as well as reduced numbers of oligodendrocytes,which were also morphologically aberrant oligodendrocytes.Expressions of markers for mature myelination,including myelin basic protein,also were reduced.The accumulating knowledge concerning the mechanisms of ethanol-induced dysmyelination could lead to the development of strategies to prevent dysmyelination in children exposed to ethanol during fetal development.Future studies using fetal oligodendrocyte-and oligodendrocyte precursor cell-derived exosomes isolated from the mother's blood may identify biomarkers for fetal alcohol syndrome and even implicate epigenetic changes in early development that affect oligodendrocyte precursor cell and oligodendrocyte function in adulthood.By combining various imaging modalities with molecular studies,it may be possible to determine which fetuses are at risk and to intervene therapeutically early in the pregnancy.
基金This work was supported by research grants from Shenzhen Fundamental Research Program(Grants No.RCYX20200714114644167,JCYJ20190809161405495,and JCYJ20210324123212035)National Natural Science Foundation of China(Grants No.81971309,32170980,and 32070964)Guangdong Basic and Applied Basic Research Foundation(Grants No.2019A1515011333 and 2022B1515020012).
文摘Oligodendrocyte lineage cells(OL-lineage cells)are a cell population that are crucial for mammalian central nervous system(CNS)myelination.OL-lineage cells go through developmental stages,initially differentiating into oligodendrocyte precursor cells(OPCs),before becoming immature oligodendrocytes,then mature oligodendrocytes(OLs).While the main function of cell lineage is in myelin formation,and increasing number of studies have turned to explore the immunological characteristics of these cells.Initially,these studies focused on discovering how OPCs and OLs are affected by the immune system,and then,how these immunological changes influence the myelination process.However,recent studies have uncovered another feature of OL-lineage cells in our immune systems.It would appear that OL-lineage cells also express immunological factors such as cytokines and chemokines in response to immune activation,and the expression of these factors changes under various pathologic conditions.Evidence suggests that OL-lineage cells actually modulate immune functions.Indeed,OL-lineage cells appear to play both"victim"and"agent"in the CNS which raises a number of questions.Here,we summarize immunologic changes in OL-lineage cells and their effects,as well as consider OL-lineage cell changes which influence immune cells under pathological conditions.We also describe some of the underlying mechanisms of these changes and their effects.Finally,we describe several studies which use OL-lineage cells as immunotherapeutic targets for demyelination diseases.
基金supported by the National Natural Science Foundation of China,No. 81241022the Natural Science Foundation of Beijing,No. 7072023,7122045
文摘Oligodendrocyte lineage gene-1 expressed in oligodendrocytes may trigger the repair of neuronal myelin impairment, and play a crucial role in myelin repair. Hypoxia-inducible factor la, a transcription factor, is of great significance in premature infants with hypoxic-ischemic brain damage There is little evidence of direct regulatory effects of hypoxia-inducible factor le on oligodendrocyte lineage gene-l. In this study, brain slices of Sprague-Dawley rats were cultured and subjected to oxygen-glucose deprivation. Then, slices were transfected with hypoxia-inducible factor la or oligodendrocyte lineage gene-1. The expression levels of hypoxia-inducible factor la and oligodendrocyte lineage gene-1 were significantly up-regulated in rat brains prior to transfection, as detected by immunohistochemical staining. Eight hours after transfection of slices with hypoxia-inducible factor la, oligodendrocyte lineage gene-1 expression was upregulated, and reached a peak 24 hours after transfection. Oligodendrocyte lineage gene-1 transfection induced no significant differences in hypoxia-inducible factor la levels in rat brain tissues with oxygen-glucose deprivation. These experimental findings indicate that hypoxia-inducible factor la can regulate oligodendrocyte lineage gene-1 expression in hypoxic brain tissue, thus repairing the neural impairment.
基金the National Natural Science Foundation of China, No. 30872778/C1704the Natural Science Foundation of Beijing, No. 7072023+1 种基金the Clinical Basic Cooperation Foundation of Capital Medical University, No. 2009jl18the Clinical Basic Cooperation Foundation of Capital Medical University, No.11JL-L03
文摘To examine the expression profiles of oligodendrocyte transcription factors 1 and 2 (Oligl and Olig2) and the interaction between these two proteins, Oligl was transfected into the lateral ventricles of neonatal rats subjected to hypoxia. Immunohistochemistry demonstrated that Olig2 was expressed throughout the nuclei in the brain, and expression increased at 3 days following hypoxia and was higher than levels at 7 days following Ad5-Oligl transfection. Western blot revealed that Oligl and Olig2 expression increased in Oligl-transfected brain cells 3 days after hypoxia, but Oligl and Olig2 expression decreased at 7 days. These results indicate that Oligl overexpression enhances Olig2 expression in brain tissues of hypoxia rats.
基金supported by the University of Florence(Fondi Ateneo,AMP),PRIN 2015E8EMCM_002(AMP)Fondazione Italiana Sclerosi Multipla(FISM)2019/R-Single/036(AMP and EC)supported by Fondazione Umberto Veronesi。
文摘Oligodendrocyte-formed myelin sheaths allow fast synaptic transmission in the brain and their degeneration leads to demyelinating diseases such as multiple sclerosis. Remyelination requires the differentiation of oligodendrocyte progenitor cells into mature oligodendrocytes but, in chronic neurodegenerative disorders, remyelination fails due to adverse environment. Therefore, a strategy to prompt oligodendrocyte progenitor cell differentiation towards myelinating oligodendrocytes is required. The neuromodulator adenosine, and its receptors(A1, A(2A), A(2B) and A3 receptors: A1R, A(2A)R, A(2B)R and A3R), are crucial mediators in remyelination processes. It is known that A1Rs facilitate oligodendrocyte progenitor cell maturation and migration whereas the A3Rs initiates apoptosis in oligodendrocyte progenitor cells. Our group of research contributed to the field by demonstrating that A(2A)R and A(2B)R inhibit oligodendrocyte progenitor cell maturation by reducing voltage-dependent K^+ currents necessary for cell differentiation. The present review summarizes the possible role of adenosine receptor ligands as potential therapeutic targets in demyelinating pathologies such as multiple sclerosis.
基金supported by the National Natural Science Foundation of China,Nos.81672171(to XY),81972074(to XY),81930070(to SQF),81620108018(to SQF),and 81772342(to GZN)the National Key R&D Program of China,No.2019YFA0112100(to SQF)the Natural Science Foundation of Tianjin of China,No.19JCZDJC34900(to XY)。
文摘Our previous studies showed that ferroptosis plays an important role in the acute and subacute stages of spinal cord injury.High intracellular iron levels and low glutathione levels make oligodendrocytes vulnerable to cell death after central nervous system trauma.In this study,we established an oligodendrocyte(OLN-93 cell line)model of ferroptosis induced by RSL-3,an inhibitor of glutathione peroxidase 4(GPX4).RSL-3 significantly increased intracellular concentrations of reactive oxygen species and malondialdehyde.RSL-3 also inhibited the main antiferroptosis pathway,i.e.,SLC7A11/glutathione/glutathione peroxidase 4(xCT/GSH/GPX4),and downregulated acyl-coenzyme A synthetase long chain family member 4.Furthermore,we evaluated the ability of several compounds to rescue oligodendrocytes from ferroptosis.Liproxstatin-1 was more potent than edaravone or deferoxamine.Liproxstatin-1 not only inhibited mitochondrial lipid peroxidation,but also restored the expression of GSH,GPX4 and ferroptosis suppressor protein 1.These findings suggest that GPX4 inhibition induces ferroptosis in oligodendrocytes,and that liproxstatin-1 is a potent inhibitor of ferroptosis.Therefore,liproxstatin-1 may be a promising drug for the treatment of central nervous system diseases.
基金funded by Shanghai Municipal Health Bureau,No.KPB-WSJ1004the National Natural Science Foundation of China,No.81200971
文摘Iron is an essential trophic element that is required for cell viability and differentiation, especially in oligodendrocytes, which consume relatively high rates of energy to produce myelin. Multiple iron metabolism proteins are expressed in the brain including transferrin receptor and ferritin-H. However, it is still unknown whether they are developmentally regulated in oligodendrocyte lineage cells for myelination. Here, using an in vitro cultured differentiation model of oligodendrocytes, we found that both transferrin receptor and ferritin-H are significantly upregulated during oligodendrocyte maturation, implying the essential role of iron in the development of oligodendrocytes. Additional different doses of Fe3+ in the cultured medium did not affect oligodendrocyte precursor cell maturation or ferritin-H expression but decreased the expression of the transferrin receptor. These results indicate that upregulation of both transferrin receptor and ferritin-H contributes to maturation and myelination of oligodendrocyte precursor cells.
基金supported by the National Natural Science Foundation of China, No. 81100916, 30400464,81271316the Postdoctoral Science Foundation of China,No. 201104901907
文摘Human umbilical mesenchymal stem cells from Wharton's jelly of the umbilical cord were induced to differentiate into oligodendrocyte precursor-like cells in vitro. Oligodendrocyte precursor cells were transplanted into contused rat spinal cords. Immunofluorescence double staining indicated that transplanted cells survived in injured spinal cord, and differentiated into mature and immature oligodendrocyte precursor cells. Biotinylated dextran amine tracing results showed that cell transplantation promoted a higher density of the corticospinal tract in the central and caudal parts of the injured spinal cord. Luxol fast blue and toluidine blue staining showed that the volume of residual myelin was significantly increased at 1 and 2 mm rostral and caudal to the lesion epicenter after cell transplantation. Furthermore, immunofluorescence staining verified that the newly regenerated myelin sheath was derived from the central nervous system. Basso, Beattie and Bresnahan testing showed an evident behavioral recovery. These results suggest that human umbilical mesenchymal stem cell-derived oligodendrocyte precursor cells promote the regeneration of spinal axons and myelin sheaths.
基金supported by the National Natural Science Foundation of China,No.81241022the Beijing Municipal Natural Science Foundation in China,No.7122045,7072023
文摘Oligodendrocyte lineage gene 1 plays a key role in hypoxic-ischemic brain damage and myelin repair, miRNA-9 is involved in the occurrence of many related neurological disorders. Bioin- formatics analysis demonstrated that miRNA-9 complementarily, but incompletely, bound oligodendrocyte lineage gene 1, but whether miRNA-9 regulates oligodendrocyte lineage gene 1 remains poorly understood. Whole brain slices of 3-day-old Sprague-Dawley rats were cultured and divided into four groups: control group; oxygen-glucose deprivation group (treatment with 8% O2 + 92% N2 and sugar-free medium for 60 minutes); transfection control group (after oxygen and glucose deprivation for 60 minutes, transfected with control plasmid) and miRNA-9 transfection group (after oxygen and glucose deprivation for 60 minutes, transfected with miRNA-9 plasmid). From the third day of transfection, and with increasing culture days, oligodendrocyte lineage gene 1 expression increased in each group, peaked at 14 days, and then decreased at 21 days. Real-time quantitative PCR results, however, demonstrated that oligoden- drocyte lineage gene 1 expression was lower in the miRNA-9 transfection group than that in the transfection control group at 1, 3, 7, 14, 21 and 28 days after transfection. Results suggested that miRNA-9 possibly negatively regulated oligodendrocyte lineage gene 1 in brain tissues during hypoxic-ischemic brain damage.
基金supported by the Study Science Foundation of the Department of Education, Yunnan Province, China, No. 2011Y184the National Natural Science Foundation of China, No. 10S090202+1 种基金Doctoral Innovation Foundation of Kunming Medical University, No. 2011D01the Natural Science Foundation of Kunming University, No. XJ11L016
文摘A contusive model of spinal cord injury at spinal segment T8-9 was established in rats. Huantiao (GB30) and Huatuojiaji (Ex-B05) were punctured with needles, and endogenous neural stem cells were labeled with 5-bromo-2'-deoxyuridine (BrdU) and NG2. Double immunofluorescence staining showed that electroacupuncture markedly increased the numbers of BrdU+/NG2+cells at spinal cord tissue 15 mm away from the injury center in the rostral and caudal directions. The results suggest that electroacupuncture promotes the proliferation of endogenous neural stem cells and oligodendrocytes in rats with spinal cord injury.
基金This project was supported by grants from Natural Science Foundation of China,Hubei Province (No.2017CFB645)and National Natural Science Foundation of China (No.81471519).
文摘Periventricular white matter injury (PWMI)is very common in survivors of premature birth,and the final outcomes are a reduction in myelinated neurons leading to white matter hypomyelination.How and (or) why the oligodendrocyte lineage develops abnormally and myelination is reduced is a hot topic in the field.This study focuses on the effect of intrauterine inflammation on the proliferation of oligodendrocyte lineage cells and the underlying mechanisms.Lipopolysaccharide (LPS)(300μg/kg)was intraperitoneally injected into pregnant Sprague-Dawley rats at embryonic days 19 and 20 to establish a rat model of intrauterine infection-induced white matter injury.Corpus callosum tissues were collected at postnatal day 14(P14)to quantify the number of oligodendrocytes,the number and proliferation of oligodendrocyte precursor cells (OPCs), and the expression of myelin proteins (MBP and PLP).Furthermore,the expression of Writ and Notch signaling-related proteins was analyzed.The results showed that the number of oligodendrocytes in the corpus callosum tissues of LPS-treated rats was reduced,and the expression levels of myelinating proteins were down-regulated.Further analysis showed that the Notch signaling pathway was down-regulated in the LPS-treated group.These results indicate that intrauterine LPS may inhibit the proliferation of OPCs by down-regulating the Notch rather than the Writ signaling pathway,leading to hypomyelination of white matter.
基金The Cell Culture Core supported by grant No.PP1498:Neural Cell Culture Core and NIH grant No.04612 Intellectual&Developmental Disabilities.The Cell,Circuits and Systems Analysis Core is supported by NICHD award No.U54HD087101-03
文摘The consequences of neonatal white matter injury are devastating and represent a major societal problem as currently there is no cure.Prematurity,low weight birth and maternal pre-natal infection are the most frequent causes of acquired myelin deficiency in the human neonate leading to cerebral palsy and cognitive impairment.In the developing brain,oligodendrocyte(OL)maturation occurs perinatally,and immature OLs are particularly vulnerable.Cell replacement therapy is often considered a viable option to replace progenitors that die due to glutamate excitotoxicity.We previously reported directed specification and mobilization of endogenous committed and uncommitted neural progenitors by the combination of transferrin and insulin growth factor 1(TSC1).Here,considering cell replacement and integration as therapeutic goals,we examined if OL progenitors(OLPs)grafted into the brain parenchyma of mice that were subjected to an excitotoxic insult could rescue white matter injury.For that purpose,we used a well-established model of glutamate excitotoxic injury.Four-day-old mice received a single intraparenchymal injection of the glutamate receptor agonist N-methyl-D-aspartate alone or in conjunction with TSC1 in the presence or absence of OLPs grafted into the brain parenchyma.Energetics and expression of stress proteins and OL developmental specific markers were examined.A comparison of the proteomic profile per treatment was also ascertained.We found that OLPs did not survive in the excitotoxic environment when grafted alone.In contrast,when combined with TSC1,survival and integration of grafted OLPs was observed.Further,energy metabolism in OLPs was significantly increased by N-methyl-D-aspartate and modulated by TSC1.The proteomic profile after the various treatments showed elevated ubiquitination and stress/heat shock protein 90 in response to N-methyl-D-aspartate.These changes were reversed in the presence of TSC1 and ubiquitination was decreased.The results obtained in this pre-clinical study indicate that the use of a combinatorial intervention including both trophic support and healthy OLPs constitutes a promising approach for long-term survival and successful graft integration.We established optimal conditioning of the host brain environment to promote long-term survival and integration of grafted OLPs into an inflamed neonate host brain.Experimental procedures were performed under the United States Public Health Service Guide for the Care and Use of Laboratory Animals and were approved by the Institutional Animal Care Committee at(UCLA)(ARC#1992-034-61)on July 1,2010.