Taurine is considered a non-essential amino acid because it is synthesized by most mammals.However,dietary intake of taurine may be necessary to achieve the physiological levels required for the development,maintenanc...Taurine is considered a non-essential amino acid because it is synthesized by most mammals.However,dietary intake of taurine may be necessary to achieve the physiological levels required for the development,maintenance,and function of certain tissues.Taurine may be especially important for the retina.The concentration of taurine in the retina is higher than that in any other tissue in the body and taurine deficiency causes retinal oxidative stress,apoptosis,and degeneration of photoreceptors and retinal ganglion cells.Low plasma taurine levels may also underlie retinal degeneration in humans and therefore,taurine administration could exert retinal neuroprotective effects.Taurine has antioxidant,anti-apoptotic,immunomodulatory,and calcium homeostasis-regulatory properties.This review summarizes the role of taurine in retinal health and disease,where it appears that taurine may be a promising nutraceutical.展开更多
Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract f...Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract following stroke,we induced photochemical infarction of the sensorimotor cortex leading to Wallerian degeneration along the full extent of the corticospinal tract.We first used a routine,sensitive marker of axonal injury,amyloid precursor protein,to examine Wallerian degeneration of the corticospinal tract.An antibody to amyloid precursor protein mapped exclusively to proximal axonal segments within the ischemic cortex,with no positive signal in distal parts of the corticospinal tract,at all time points.To improve visualization of Wallerian degeneration,we next utilized an orthograde virus that expresses green fluorescent protein to label the corticospinal tract and then quantitatively evaluated green fluorescent protein-expressing axons.Using this approach,we found that axonal degeneration began on day 3 post-stroke and was almost complete by 7 days after stroke.In addition,microglia mobilized and activated early,from day 7 after stroke,but did not maintain a phagocytic state over time.Meanwhile,astrocytes showed relatively delayed mobilization and a moderate response to Wallerian degeneration.Moreover,no anterograde degeneration of spinal anterior horn cells was observed in response to Wallerian degeneration of the corticospinal tract.In conclusion,our data provide evidence for dynamic,pathogenic spatiotemporal changes in major cellular components of the corticospinal tract during Wallerian degeneration.展开更多
Macrophages play an important role in peripheral nerve regeneration,but the specific mechanism of regeneration is still unclear.Our preliminary findings indicated that neutrophil peptide 1 is an innate immune peptide ...Macrophages play an important role in peripheral nerve regeneration,but the specific mechanism of regeneration is still unclear.Our preliminary findings indicated that neutrophil peptide 1 is an innate immune peptide closely involved in peripheral nerve regeneration.However,the mechanism by which neutrophil peptide 1 enhances nerve regeneration remains unclear.This study was designed to investigate the relationship between neutrophil peptide 1 and macrophages in vivo and in vitro in peripheral nerve crush injury.The functions of RAW 264.7 cells we re elucidated by Cell Counting Kit-8 assay,flow cytometry,migration assays,phagocytosis assays,immunohistochemistry and enzyme-linked immunosorbent assay.Axonal debris phagocytosis was observed using the CUBIC(Clear,Unobstructed Brain/Body Imaging Cocktails and Computational analysis)optical clearing technique during Wallerian degeneration.Macrophage inflammatory factor expression in different polarization states was detected using a protein chip.The results showed that neutrophil peptide 1 promoted the prolife ration,migration and phagocytosis of macrophages,and CD206 expression on the surfa ce of macrophages,indicating M2 polarization.The axonal debris clearance rate during Wallerian degeneration was enhanced after neutrophil peptide 1 intervention.Neutrophil peptide 1 also downregulated inflammatory factors interleukin-1α,-6,-12,and tumor necrosis factor-αin invo and in vitro.Thus,the results suggest that neutrophil peptide 1 activates macrophages and accelerates Wallerian degeneration,which may be one mechanism by which neutrophil peptide 1 enhances peripheral nerve regeneration.展开更多
Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the elderly.Strikingly,there is a scarcity of curative therapies,especially for th...Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the elderly.Strikingly,there is a scarcity of curative therapies,especially for the atrophic advanced form of age-related macular degeneration,likely due to the lack of models able to fully recapitulate the native structure of the outer blood retinal barrier,the prime to rget tissue of age-related macular degeneration.Standard in vitro systems rely on 2D monocultures unable to adequately reproduce the structure and function of the outer blood retinal barrier,integrated by the dynamic interaction of the retinal pigment epithelium,the Bruch's membrane,and the underlying choriocapillaris.The Bruch's membrane provides structu ral and mechanical support and regulates the molecular trafficking in the outer blood retinal barrier,and therefo re adequate Bruch's membrane-mimics are key for the development of physiologically relevant models of the outer blood retinal barrie r.In the last years,advances in the field of biomaterial engineering have provided novel approaches to mimic the Bruch's membrane from a variety of materials.This review provides a discussion of the integrated properties and function of outer blood retinal barrier components in healt hy and age-related macular degeneration status to understand the requirements to adequately fabricate Bruch's membrane biomimetic systems.Then,we discuss novel materials and techniques to fabricate Bruch's membrane-like scaffolds for age-related macular degeneration in vitro modeling,discussing their advantages and challenges with a special focus on the potential of Bruch's membrane-like mimics based on decellularized tissue.展开更多
Modern neuroscience began from all reaching and fierce conflict between“neuronismo and reticulismo”——between neuronal and reticular theories of the organization of the nervous system;the conflict culminated in Dec...Modern neuroscience began from all reaching and fierce conflict between“neuronismo and reticulismo”——between neuronal and reticular theories of the organization of the nervous system;the conflict culminated in December of 1906 in Stockholm where Santiago Ramon y Cajal(the proponent of the neuronal doctrine)and Camillo Golgi(who advocated the syncytial reticular organization of neural networks)delivered their Noble prize lectures(Verkhratsky,2009).展开更多
AIM:To describe the clinical,electrophysiological,and genetic features of an unusual case with an RDH12 homozygous pathogenic variant and reviewed the characteristics of the patients reported with the same variant.MET...AIM:To describe the clinical,electrophysiological,and genetic features of an unusual case with an RDH12 homozygous pathogenic variant and reviewed the characteristics of the patients reported with the same variant.METHODS:The patient underwent a complete ophthalmologic examination including best-corrected visual acuity,anterior segment and dilated fundus,visual field,spectral-domain optical coherence tomography(OCT)and electroretinogram(ERG).The retinal disease panel genes were sequenced through chip capture high-throughput sequencing and Sanger sequencing was used to confirm the result.Then we reviewed the characteristics of the patients reported with the same variant.RESULTS:A 30-year male presented with severe early retinal degeneration who complained night blindness,decreased visual acuity,vitreous floaters and amaurosis fugax.The best corrected vision was 0.04 OD and 0.12 OS,respectively.The fundus photo and OCT showed bilateral macular atrophy but larger areas of macular atrophy in the left eye.Autofluorescence shows bilateral symmetrical hypo-autofluorescence.ERG revealed that the amplitudes of a-and b-wave were severely decreased.Multifocal ERG showed decreased amplitudes in the local macular area.A homozygous missense variant c.146C>T(chr14:68191267)was found.The clinical characteristics of a total of 13 patients reported with the same pathologic variant varied.CONCLUSION:An unusual patient with a homozygous pathogenic variant in the c.146C>T of RDH12 which causes late-onset and asymmetric retinal degeneration are reported.The clinical manifestations of the patient with multimodal retinal imaging and functional examinations have enriched our understanding of this disease.展开更多
AIM:To explore the usage of choroidal thickness measured by swept-source optical coherence tomography(SS-OCT)to detect myopic macular degeneration(MMD)in high myopic participants.METHODS:Participants with bilateral hi...AIM:To explore the usage of choroidal thickness measured by swept-source optical coherence tomography(SS-OCT)to detect myopic macular degeneration(MMD)in high myopic participants.METHODS:Participants with bilateral high myopia(≤−6 diopters)were recruited from a subset of the Guangzhou Zhongshan Ophthalmic Center-Brien Holden Vision Institute High Myopia Cohort Study.SS-OCT was performed to determine the choroidal thickness,and myopic maculopathy was graded by the International Meta-Analysis for Pathologic Myopia(META-PM)Classification.Presence of MMD was defined as META-PM category 2 or above.RESULTS:A total of 568 right eyes were included for analysis.Eyes with MMD(n=106,18.7%)were found to have older age,longer axial lengths(AL),higher myopic spherical equivalents(SE),and reduced choroidal thickness in each Early Treatment Diabetic Retinopathy Study(ETDRS)grid sector(P<0.001).The area under the receiver operating characteristic(ROC)curves(AUC)for subfoveal choroidal thickness(0.907)was greater than that of the model,including age,AL,and SE at 0.6249,0.8208,and 0.8205,respectively.The choroidal thickness of the inner and outer nasal sectors was the most accurate indicator of MMD(AUC of 0.928 and 0.923,respectively).An outer nasal sector choroidal thickness of less than 74μm demonstrated the highest odds of predicting MMD(OR=33.8).CONCLUSION:Choroidal thickness detects the presence of MMD with high agreement,particularly of the inner and outer nasal sectors of the posterior pole,which appears to be a biometric parameter more precise than age,AL,or SE.展开更多
Our previous studies have shown that long noncoding RNA(lncRNA)H19 is upregulated in injured rat sciatic nerve during the process of Wallerian degeneration,and that it promotes the migration of Schwann cells and slows...Our previous studies have shown that long noncoding RNA(lncRNA)H19 is upregulated in injured rat sciatic nerve during the process of Wallerian degeneration,and that it promotes the migration of Schwann cells and slows down the growth of dorsal root ganglion axons.However,the mechanism by which lncRNA H19 regulates neural repair and regeneration after peripheral nerve injury remains unclear.In this study,we established a Sprague-Dawley rat model of sciatic nerve transection injury.We performed in situ hybridization and found that at 4–7 days after sciatic nerve injury,lncRNA H19 was highly expressed.At 14 days before injury,adeno-associated virus was intrathecally injected into the L4–L5 foramina to disrupt or overexpress lncRNA H19.After overexpression of lncRNA H19,the growth of newly formed axons from the sciatic nerve was inhibited,whereas myelination was enhanced.Then,we performed gait analysis and thermal pain analysis to evaluate rat behavior.We found that lncRNA H19 overexpression delayed the recovery of rat behavior function,whereas interfering with lncRNA H19 expression improved functional recovery.Finally,we examined the expression of lncRNA H19 downstream target SEMA6D,and found that after lncRNA H19 overexpression,the SEMA6D protein level was increased.These findings suggest that lncRNA H19 regulates peripheral nerve degeneration and regeneration through activating SEMA6D in injured nerves.This provides a new clue to understand the role of lncRNA H19 in peripheral nerve degeneration and regeneration.展开更多
The majority of inherited retinal degenerative diseases and dry age-related macular degeneration are characterized by decay of the outer retina and photoreceptors,which leads to progressive loss of vision.The inner re...The majority of inherited retinal degenerative diseases and dry age-related macular degeneration are characterized by decay of the outer retina and photoreceptors,which leads to progressive loss of vision.The inner retina,including second-and third-order retinal neurons,also shows aberrant structural changes at all stages of degeneration.Müller glia,the major glial cells maintain retinal homeostasis,activating and rearranging immediately in response to photoreceptor stress.These phenomena are collectively known as retinal remodeling and are anatomically well described,but their impact on visual function is less well characterized.Retinal remodeling has traditionally been considered a detrimental chain of events that decreases visual function.However,emerging evidence from functional assays suggests that remodeling could also be a part of a survival mechanism wherein the inner retina responds plastically to outer retinal degeneration.The visual system’s first synapses between the photoreceptors and bipolar cells undergo rewiring and functionally compensate to maintain normal signal output to the brain.Distinct classes of retinal ganglion cells remain even after the massive loss of photoreceptors.Müller glia possess the regenerative potential for retinal recovery and possibly exert adaptive transcriptional changes in response to neuronal loss.These types of homeostatic changes could potentially explain the well-maintained visual function observed in patients with inherited retinal degenerative diseases who display prominent anatomic retinal pathology.This review will focus on our current understanding of retinal neuronal and Müller glial adaptation for the potential preservation of retinal activity during photoreceptor degeneration.Targeting retinal self-compensatory responses could help generate universal strategies to delay sensory disease progression.展开更多
Age-related macular degeneration is a primary cause of blindness in the older adult population. Past decades of research in the pathophysiology of the disease have resulted in breakthroughs in the form of anti-vascula...Age-related macular degeneration is a primary cause of blindness in the older adult population. Past decades of research in the pathophysiology of the disease have resulted in breakthroughs in the form of anti-vascular endothelial growth factor therapies against neovascular age-related macular degeneration;however, effective treatment is not yet available for geographical atrophy in dry agerelated macular degeneration or for preventing the progression from early or mid to the late stage of age-related macular degeneration. Both clinical and experimental investigations involving human agerelated macular degeneration retinas and animal models point towards the atrophic alterations in retinal pigment epithelium as a key feature in age-related macular degeneration progression. Retinal pigment epithelium cells are primarily responsible for cellular-structural maintenance and nutrition supply to keep photoreceptors healthy and functional. The retinal pigment epithelium constantly endures a highly oxidative environment that is balanced with a cascade of antioxidant enzyme systems regulated by nuclear factor erythroid-2-related factor 2 as a main redox sensing transcription factor. Aging and accumulated oxidative stress triggers retinal pigment epithelium dysfunction and eventually death. Exposure to both environmental and genetic factors aggravates oxidative stress damage in aging retinal pigment epithelium and accelerates retinal pigment epithelium degeneration in age-related macular degeneration pathophysiology. The present review summarizes the role of oxidative stress in retinal pigment epithelium degeneration, with potential impacts from both genetic and environmental factors in age-related macular degeneration development and progression. Potential strategies to counter retinal pigment epithelium damage and protect the retinal pigment epithelium through enhancing its antioxidant capacity are also discussed, focusing on existing antioxidant nutritional supplementation, and exploring nuclear factor erythroid-2-related factor 2 and its regulators including REV-ERBα as therapeutic targets to protect against age-related macular degeneration development and progression.展开更多
Chronic spinal cord compression(CSCC)is induced by disc herniation and other reasons,leading to movement and sensation dysfunction,with a serious impact on quality of life.Spontaneous disc herniation rarely occurs in ...Chronic spinal cord compression(CSCC)is induced by disc herniation and other reasons,leading to movement and sensation dysfunction,with a serious impact on quality of life.Spontaneous disc herniation rarely occurs in rodents,and therefore establishing a chronic spinal cord compression(CSCC)animal model is of crucial importance to explore the pathogenesis and treatment of CSCC.The absence of secreted protein,acidic,and rich in cysteine(SPARC)leads to spontaneous intervertebral disc degeneration in mice,which resembles human disc degeneration.In this study,we evaluated whether SPARC-null mice may serve as an animal model for CSCC.We performed rod rotation test,pain threshold test,gait analysis,and Basso Mouse Scale score.Our results showed that the motor function of SPARC-null mice was weakened,and magnetic resonance images revealed compression at different spinal cord levels,particularly in the lumbar segments.Immunofluorescence staining and western blot assay showed that the absence of SPARC induced apoptosis of neurons and oligodendrocytes,activation of microglia/macrophages with M1/M2 phenotype and astrocytes with A1/A2 phenotype;it also activated the expression of the NOD-like receptor protein 3 inflammasome and inhibited brain-derived neurotrophic factor/tyrosine kinase B signaling pathway.Notably,these findings are characteristics of CSCC.Therefore,we propose that SPARC-null mice may be an animal model for studying CSCC caused by disc herniation.展开更多
Neurodegeneration of the central nervous system(CNS)underscores many of humanity’s most debilitating diseases,including Alzheimer’s disease,Parkinson’s disease,and multiple sclerosis.Recently,the nitric oxide-guany...Neurodegeneration of the central nervous system(CNS)underscores many of humanity’s most debilitating diseases,including Alzheimer’s disease,Parkinson’s disease,and multiple sclerosis.Recently,the nitric oxide-guanylate cyclase-cyclic guanosine monophosphate(NOGC-cGMP)signaling pathway has gained traction as a neuroprotective pathway in the CNS.As an extension of the CNS,the retina is also susceptible to neurodegeneration with age.The most prevalent optic neuropathy is glaucoma,the world’s leading cause of irreversible blindness,predicted to affect more than 112 million people worldwide by 2040(Calkins,2021).In glaucoma,vision loss occurs due to the progressive degeneration of retinal ganglion cells(RGCs),the output neurons of the retina,along with their axons which form the optic nerve(Wareham et al.,2022).Degeneration of RGCs leads to a characteristic pattern of scotopic visual field deficiencies that spread from one retinotopic sector to the next(Elze et al.,2015).Visual deficits are linked to increasing age and the sensitivity of RGCs to intraocular pressure(Calkins,2021).展开更多
·AIM:To evaluate visual outcomes and changes in fluid after administering monthly anti-vascular endothelial growth factor(VEGF)injections to treat neovascular agerelated macular degeneration(n AMD)with subretinal...·AIM:To evaluate visual outcomes and changes in fluid after administering monthly anti-vascular endothelial growth factor(VEGF)injections to treat neovascular agerelated macular degeneration(n AMD)with subretinal fluid(SRF)and pigment epithelial detachment(PED).·METHODS:This prospective study included eyes with n AMD previously treated with as-needed anti-VEGF injections.The patients were treated with six monthly intravitreal injections of ranibizumab.Quantitative volumetric segmentation analyses of the SRF and PED were performed.The main outcome measures included best-corrected visual acuity(BCVA),and SRF and PED volumes.·RESULTS:Twenty eyes of 20 patients were included in this study.At the 6-month follow-up,BCVA and PED volume did not change significantly(P=0.110 and 0.999,respectively)but the mean SRF volume decreased from 0.53±0.82 mm3 at baseline to 0.08±0.23 mm3(P=0.002).The absorption rate of the SRF volume was negatively correlated with the duration of previous antiVEGF treatment(P=0.029).Seven of the 20 eyes(35%)showed a fluid-free macula and significant improvement in BCVA(P=0.036)by month 6.·CONCLUSION:Quantifying the SRF can precisely determine the patient’s responsiveness to anti-VEGF treatment of n AMD.展开更多
Age-related macular degeneration is a major global cause of central visual impairment and seve re vision loss.With an aging population,the already immense economic burden of costly anti-vascular endothelial growth fa ...Age-related macular degeneration is a major global cause of central visual impairment and seve re vision loss.With an aging population,the already immense economic burden of costly anti-vascular endothelial growth fa ctor treatment is likely to increase.In addition,current conventional treatment is only available for the late neovascular stage of age-related macular degeneration,and injections can come with potentially devastating complications,introducing the need for more economical and ris kfree treatment.In recent years,exosomes,which are nano-sized extracellular vesicles of an endocytic origin,have shown immense potential as diagnostic biomarkers and in the therapeutic application,as they are bestowed with characte ristics including an expansive cargo that closely resembles their parent cell and exceptional ability of intercellular communication and targeting neighboring cells.Exosomes are currently undergoing clinical trials for various conditions such as type 1 diabetes and autoimmune diseases;however,exosomes as a potential therapy for seve ral retinal diseases have just begun to undergo scrutinizing investigation with little literature on age-related macular degeneration specifically.This article will focus on the limited literature availa ble on exosome transplantation treatment in age-related macular degeneration animal models and in vitro cell cultures,as well as briefly identify future research directions.Current literature on exosome therapy using agerelated macular degeneration rodent models includes laser retinal injury,N-methyl-N-nitrosourea,and royal college of surgeon models,which mimic inflammatory and degenerative aspects of agerelated macular degeneration.These have shown promising results in preserving retinal function and morphology,as well as protecting photoreceptors from apoptosis.Exosomes from their respective cellular origins may also act by regulating the expression of various inflammatory cyto kines,mRNAs,and proteins involved in photo receptor degeneration pathways to exert a therapeutic effect.Various findings have also opened exciting prospects for the involvement of cargo components in remedial effects on the damaged macula or retina.展开更多
Slit-Robo GTPase-activating protein 2(SRGAP2) plays important roles in axon guidance, neuronal migration, synapse formation, and nerve regeneration. However, the role of SRGAP2 in neuroretinal degenerative disease rem...Slit-Robo GTPase-activating protein 2(SRGAP2) plays important roles in axon guidance, neuronal migration, synapse formation, and nerve regeneration. However, the role of SRGAP2 in neuroretinal degenerative disease remains unclear. In this study, we found that SRGAP2 protein was first expressed in the retina of normal mice at the embryonic stage and was mainly located in the mature retinal ganglion cell layer and the inner nuclear layer. SRGAP2 protein in the retina and optic nerve increased after optic nerve crush. Then, we established a heterozygous knockout(Srgap2+/–) mouse model of optic nerve crush and found that Srgap2 suppression increased retinal ganglion cell survival, lowered intraocular pressure, inhibited glial cell activation, and partially restored retinal function. In vitro experiments showed that Srgap2 suppression activated the mammalian target of rapamycin signaling pathway. RNA sequencing results showed that the expression of small heat shock protein genes(Cryaa, Cryba4, and Crygs) related to optic nerve injury were upregulated in the retina of Srgap2+/– mice. These results suggest that Srgap2 suppression reduced the robust activation of glial cells, activated the mammalian target of rapamycin signaling pathway related to nerve protein, increased the expression of small heat shock protein genes, inhibited the degeneration of retinal ganglion cells, and partially restored optic nerve function.展开更多
Dendrites play irreplaceable roles in the nerve conduction pathway and are vulnerable to various insults.Peripheral axotomy of motor neurons results in the retraction of dendritic arbors,and the dendritic arbor can be...Dendrites play irreplaceable roles in the nerve conduction pathway and are vulnerable to various insults.Peripheral axotomy of motor neurons results in the retraction of dendritic arbors,and the dendritic arbor can be re-expanded when reinnervation is allowed.RhoA is a target that regulates the cytoskeleton and promotes neuronal survival and axon regeneration.However,the role of RhoA in dendrite degeneration and regeneration is unknown.In this study,we explored the potential role of RhoA in dendrites.A line of motor neuronal conditional knockout mice was developed by crossbreeding HB9~(Cre+)mice with RhoA~(flox/flox)mice.We established two models for assaying dendrite degeneration and regeneration,in which the brachial plexus was transection or crush injured,respectively.We found that at 28 days after brachial plexus transection,the density,complexity,and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice were slightly decreased compared with that in Cre mice.Dendrites underwent degeneration at 7 and 14 days after brachial plexus transection and recovered at 28–56 days.The density,complexity,and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice recovered compared with results in Cre mice.These findings suggest that RhoA knockout in motor neurons attenuates dendrite degeneration and promotes dendrite regeneration after peripheral nerve injury.展开更多
Neurite degeneration,a major component of many neurodegenerative diseases,such as Parkinson’s disease,Alzheimer’s disease,and amyotrophic lateral sclerosis,is not part of the typical apoptosis signaling mechanism,bu...Neurite degeneration,a major component of many neurodegenerative diseases,such as Parkinson’s disease,Alzheimer’s disease,and amyotrophic lateral sclerosis,is not part of the typical apoptosis signaling mechanism,but rather it appears that a self-destructive process is in action.Oxidative stress is a well-known inducer of neurodegenerative pathways:neuronal cell death and neurite degeneration.Although oxidative stress exerts cytotoxic effects leading to neuronal loss,the pathogenic mechanisms and precise signaling pathways by which oxidative stress causes neurite degeneration have remained entirely unknown.We previously reported that reactive oxygen species generated by NADPH oxidases induce activation of the E3 ubiquitin ligase ZNRF1 in neurons,which promotes neurite degeneration.In this process,the phosphorylation of an NADPH oxidase subunit p47-phox at the 345serine residue serves as an important checkpoint to initiate the ZNRF1-dependent neurite degeneration.Evidence provides new insights into the mechanism of reactive oxygen species-mediated neurodegeneration.In this review,we focus specifically on reactive oxygen species-induced neurite degeneration by highlighting a phosphorylation-dependent regulation of the molecular interaction between ZNRF1 and the NADPH oxidase complex.展开更多
Vision is one of our most precious senses,and its impairment has a high socio-economic impact.In the industrialized world,degenerative diseases of the retina lead to vision loss,particularly among the elderly.These de...Vision is one of our most precious senses,and its impairment has a high socio-economic impact.In the industrialized world,degenerative diseases of the retina lead to vision loss,particularly among the elderly.These degenerations include,for instance,retinitis pigmentosa,age-related macular degeneration,and diabetic retinopathy.Although treatments are evolving to manage late-stage symptoms of retinal degenerations,no effective therapies to recover vision loss exist.Retinal degeneration often involves loss or damage to specialized neural cells,such as photoreceptors,and their death stimulates the activation and proliferation of Müller cells(Salman et al.,2021).展开更多
Peripheral nerve injury(PNI)causes sensory and motor deficits as well as neuropathic pain,which seriously impacts patient quality of life(Jiang et al.,2017).Morphological and molecular changes in the spinal cord and d...Peripheral nerve injury(PNI)causes sensory and motor deficits as well as neuropathic pain,which seriously impacts patient quality of life(Jiang et al.,2017).Morphological and molecular changes in the spinal cord and dorsal root ganglia(DRG),such as neuronal cell death,nerve fiber degeneration,and glial activation,are strongly associated with PNI-induced pathological syndromes.展开更多
Age-related macular degeneration(AMD) is the most common cause of blindness in the United States in adults over 55 years of age and is one of the leading global causes of blindness: at least 196 million of the worldwi...Age-related macular degeneration(AMD) is the most common cause of blindness in the United States in adults over 55 years of age and is one of the leading global causes of blindness: at least 196 million of the worldwide population have AMD, and prevalence is projected to rise to 288 million by 2040(Lin et al., 2021). As cases and disease burden increase, improvements in the characterization of AMD pathobiology and exploration of potential therapeutic solutions are necessary first steps in addressing this global health concern.展开更多
基金supported by Instituto de Salud CarlosⅢ(ISCⅢ):PI19/00203cofunded by ERDF+9 种基金"A way to make Europe"to MPVP and DGAP122/00900RD16/0008/0026 co-funded by ERDF"A way to make Europe"to MPVP and RD21/0002/0014financiado porla Unión Europea-NextGenerationEUFundación Robles Chillida to DGARED2018-102499-TPID201 9-106498GB-I00funded by MCIN/AEI/10.13039/501100011 033 to MVSIHU FOReSIGHT[ANR-18-IAHU-0001] to SP
文摘Taurine is considered a non-essential amino acid because it is synthesized by most mammals.However,dietary intake of taurine may be necessary to achieve the physiological levels required for the development,maintenance,and function of certain tissues.Taurine may be especially important for the retina.The concentration of taurine in the retina is higher than that in any other tissue in the body and taurine deficiency causes retinal oxidative stress,apoptosis,and degeneration of photoreceptors and retinal ganglion cells.Low plasma taurine levels may also underlie retinal degeneration in humans and therefore,taurine administration could exert retinal neuroprotective effects.Taurine has antioxidant,anti-apoptotic,immunomodulatory,and calcium homeostasis-regulatory properties.This review summarizes the role of taurine in retinal health and disease,where it appears that taurine may be a promising nutraceutical.
基金supported by the National Natural Science Foundation of China,Nos.31 730030 (to XL),81941011 (to XL),31 771053 (to HD),82271403 (to XL),82272171 (to ZY),31971279 (to ZY)82201542 (to FH)+1 种基金the Natural Science Foundation of Beijing,No.7222004 (to HD)the Science and Technology Program of Beijing,No.Z181100001818007(to ZY)
文摘Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract following stroke,we induced photochemical infarction of the sensorimotor cortex leading to Wallerian degeneration along the full extent of the corticospinal tract.We first used a routine,sensitive marker of axonal injury,amyloid precursor protein,to examine Wallerian degeneration of the corticospinal tract.An antibody to amyloid precursor protein mapped exclusively to proximal axonal segments within the ischemic cortex,with no positive signal in distal parts of the corticospinal tract,at all time points.To improve visualization of Wallerian degeneration,we next utilized an orthograde virus that expresses green fluorescent protein to label the corticospinal tract and then quantitatively evaluated green fluorescent protein-expressing axons.Using this approach,we found that axonal degeneration began on day 3 post-stroke and was almost complete by 7 days after stroke.In addition,microglia mobilized and activated early,from day 7 after stroke,but did not maintain a phagocytic state over time.Meanwhile,astrocytes showed relatively delayed mobilization and a moderate response to Wallerian degeneration.Moreover,no anterograde degeneration of spinal anterior horn cells was observed in response to Wallerian degeneration of the corticospinal tract.In conclusion,our data provide evidence for dynamic,pathogenic spatiotemporal changes in major cellular components of the corticospinal tract during Wallerian degeneration.
基金supported by the National Natural Science Foundation of China,No.32371048(to YK)the Peking University People’s Hospital Research and Development Funds,No.RDX2021-01(to YK)the Natural Science Foundation of Beijing,No.7222198(to NH)。
文摘Macrophages play an important role in peripheral nerve regeneration,but the specific mechanism of regeneration is still unclear.Our preliminary findings indicated that neutrophil peptide 1 is an innate immune peptide closely involved in peripheral nerve regeneration.However,the mechanism by which neutrophil peptide 1 enhances nerve regeneration remains unclear.This study was designed to investigate the relationship between neutrophil peptide 1 and macrophages in vivo and in vitro in peripheral nerve crush injury.The functions of RAW 264.7 cells we re elucidated by Cell Counting Kit-8 assay,flow cytometry,migration assays,phagocytosis assays,immunohistochemistry and enzyme-linked immunosorbent assay.Axonal debris phagocytosis was observed using the CUBIC(Clear,Unobstructed Brain/Body Imaging Cocktails and Computational analysis)optical clearing technique during Wallerian degeneration.Macrophage inflammatory factor expression in different polarization states was detected using a protein chip.The results showed that neutrophil peptide 1 promoted the prolife ration,migration and phagocytosis of macrophages,and CD206 expression on the surfa ce of macrophages,indicating M2 polarization.The axonal debris clearance rate during Wallerian degeneration was enhanced after neutrophil peptide 1 intervention.Neutrophil peptide 1 also downregulated inflammatory factors interleukin-1α,-6,-12,and tumor necrosis factor-αin invo and in vitro.Thus,the results suggest that neutrophil peptide 1 activates macrophages and accelerates Wallerian degeneration,which may be one mechanism by which neutrophil peptide 1 enhances peripheral nerve regeneration.
基金supported by the Ministry of Science and Innovation of Spain,"Instituto de Salud CarlosⅢ","Fon do de Investigacion Sanitaria" (PI19/00265)funds FEDER"Una manera de hacer Europa" (to BM)。
文摘Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the elderly.Strikingly,there is a scarcity of curative therapies,especially for the atrophic advanced form of age-related macular degeneration,likely due to the lack of models able to fully recapitulate the native structure of the outer blood retinal barrier,the prime to rget tissue of age-related macular degeneration.Standard in vitro systems rely on 2D monocultures unable to adequately reproduce the structure and function of the outer blood retinal barrier,integrated by the dynamic interaction of the retinal pigment epithelium,the Bruch's membrane,and the underlying choriocapillaris.The Bruch's membrane provides structu ral and mechanical support and regulates the molecular trafficking in the outer blood retinal barrier,and therefo re adequate Bruch's membrane-mimics are key for the development of physiologically relevant models of the outer blood retinal barrie r.In the last years,advances in the field of biomaterial engineering have provided novel approaches to mimic the Bruch's membrane from a variety of materials.This review provides a discussion of the integrated properties and function of outer blood retinal barrier components in healt hy and age-related macular degeneration status to understand the requirements to adequately fabricate Bruch's membrane biomimetic systems.Then,we discuss novel materials and techniques to fabricate Bruch's membrane-like scaffolds for age-related macular degeneration in vitro modeling,discussing their advantages and challenges with a special focus on the potential of Bruch's membrane-like mimics based on decellularized tissue.
基金sponsored by a grant from the National Institute of Neurological Disorders and Stroke:RO1NS116059(to MZ)。
文摘Modern neuroscience began from all reaching and fierce conflict between“neuronismo and reticulismo”——between neuronal and reticular theories of the organization of the nervous system;the conflict culminated in December of 1906 in Stockholm where Santiago Ramon y Cajal(the proponent of the neuronal doctrine)and Camillo Golgi(who advocated the syncytial reticular organization of neural networks)delivered their Noble prize lectures(Verkhratsky,2009).
基金Supported by Shenzhen Science and Technology Program,Shenzhen,China(No.JCYJ20200109145001814,No.SGDX20211123120001001)the National Natural Science Foundation of China(No.81970790)Sanming Project of Medicine in Shenzhen(No.SZSM202011015).
文摘AIM:To describe the clinical,electrophysiological,and genetic features of an unusual case with an RDH12 homozygous pathogenic variant and reviewed the characteristics of the patients reported with the same variant.METHODS:The patient underwent a complete ophthalmologic examination including best-corrected visual acuity,anterior segment and dilated fundus,visual field,spectral-domain optical coherence tomography(OCT)and electroretinogram(ERG).The retinal disease panel genes were sequenced through chip capture high-throughput sequencing and Sanger sequencing was used to confirm the result.Then we reviewed the characteristics of the patients reported with the same variant.RESULTS:A 30-year male presented with severe early retinal degeneration who complained night blindness,decreased visual acuity,vitreous floaters and amaurosis fugax.The best corrected vision was 0.04 OD and 0.12 OS,respectively.The fundus photo and OCT showed bilateral macular atrophy but larger areas of macular atrophy in the left eye.Autofluorescence shows bilateral symmetrical hypo-autofluorescence.ERG revealed that the amplitudes of a-and b-wave were severely decreased.Multifocal ERG showed decreased amplitudes in the local macular area.A homozygous missense variant c.146C>T(chr14:68191267)was found.The clinical characteristics of a total of 13 patients reported with the same pathologic variant varied.CONCLUSION:An unusual patient with a homozygous pathogenic variant in the c.146C>T of RDH12 which causes late-onset and asymmetric retinal degeneration are reported.The clinical manifestations of the patient with multimodal retinal imaging and functional examinations have enriched our understanding of this disease.
基金Supported by the National Natural Science Foundation of China(No.82301249,No.82371086)the Science and Technology Projects in Guangzhou(No.SL2024A04J01756)the Fundamental Research Funds of the State Key Laboratory of Ophthalmology(No.83000-32030003).
文摘AIM:To explore the usage of choroidal thickness measured by swept-source optical coherence tomography(SS-OCT)to detect myopic macular degeneration(MMD)in high myopic participants.METHODS:Participants with bilateral high myopia(≤−6 diopters)were recruited from a subset of the Guangzhou Zhongshan Ophthalmic Center-Brien Holden Vision Institute High Myopia Cohort Study.SS-OCT was performed to determine the choroidal thickness,and myopic maculopathy was graded by the International Meta-Analysis for Pathologic Myopia(META-PM)Classification.Presence of MMD was defined as META-PM category 2 or above.RESULTS:A total of 568 right eyes were included for analysis.Eyes with MMD(n=106,18.7%)were found to have older age,longer axial lengths(AL),higher myopic spherical equivalents(SE),and reduced choroidal thickness in each Early Treatment Diabetic Retinopathy Study(ETDRS)grid sector(P<0.001).The area under the receiver operating characteristic(ROC)curves(AUC)for subfoveal choroidal thickness(0.907)was greater than that of the model,including age,AL,and SE at 0.6249,0.8208,and 0.8205,respectively.The choroidal thickness of the inner and outer nasal sectors was the most accurate indicator of MMD(AUC of 0.928 and 0.923,respectively).An outer nasal sector choroidal thickness of less than 74μm demonstrated the highest odds of predicting MMD(OR=33.8).CONCLUSION:Choroidal thickness detects the presence of MMD with high agreement,particularly of the inner and outer nasal sectors of the posterior pole,which appears to be a biometric parameter more precise than age,AL,or SE.
基金supported by the National Natural Science Foundation of China,Nos.31971277(to DBY),31950410551(to DBY)Scientific Research Foundation for Returned Scholars,Ministry of Education of China(to DBY)+2 种基金a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)(to DBY)the Postgraduate Research&Practice Innovation Program of Jiangsu Province of China,No.KYCX 19-2050(to JS)Jiangsu College Students’Innovation and Entrepreneurship Training Program,No.202213993005Y(to YY)。
文摘Our previous studies have shown that long noncoding RNA(lncRNA)H19 is upregulated in injured rat sciatic nerve during the process of Wallerian degeneration,and that it promotes the migration of Schwann cells and slows down the growth of dorsal root ganglion axons.However,the mechanism by which lncRNA H19 regulates neural repair and regeneration after peripheral nerve injury remains unclear.In this study,we established a Sprague-Dawley rat model of sciatic nerve transection injury.We performed in situ hybridization and found that at 4–7 days after sciatic nerve injury,lncRNA H19 was highly expressed.At 14 days before injury,adeno-associated virus was intrathecally injected into the L4–L5 foramina to disrupt or overexpress lncRNA H19.After overexpression of lncRNA H19,the growth of newly formed axons from the sciatic nerve was inhibited,whereas myelination was enhanced.Then,we performed gait analysis and thermal pain analysis to evaluate rat behavior.We found that lncRNA H19 overexpression delayed the recovery of rat behavior function,whereas interfering with lncRNA H19 expression improved functional recovery.Finally,we examined the expression of lncRNA H19 downstream target SEMA6D,and found that after lncRNA H19 overexpression,the SEMA6D protein level was increased.These findings suggest that lncRNA H19 regulates peripheral nerve degeneration and regeneration through activating SEMA6D in injured nerves.This provides a new clue to understand the role of lncRNA H19 in peripheral nerve degeneration and regeneration.
基金supported by NIH R01EY032492Boston Children’s Hospital(OFD/BTREC/CTREC Faculty Career Development Grant 97906,Pilot Grant 92214,and Ophthalmology Foundation 85010)+5 种基金Mass Lions Eye Foundation 87820Blind Children’s Center 89282(to ZF)Academy of Finland grant 346295Finnish Eye and Tissue Bank FoundationRetina Registered Association(Finland)Sokeain Yst?v?t/De Blindas V?nner Registered Association(to HOL)。
文摘The majority of inherited retinal degenerative diseases and dry age-related macular degeneration are characterized by decay of the outer retina and photoreceptors,which leads to progressive loss of vision.The inner retina,including second-and third-order retinal neurons,also shows aberrant structural changes at all stages of degeneration.Müller glia,the major glial cells maintain retinal homeostasis,activating and rearranging immediately in response to photoreceptor stress.These phenomena are collectively known as retinal remodeling and are anatomically well described,but their impact on visual function is less well characterized.Retinal remodeling has traditionally been considered a detrimental chain of events that decreases visual function.However,emerging evidence from functional assays suggests that remodeling could also be a part of a survival mechanism wherein the inner retina responds plastically to outer retinal degeneration.The visual system’s first synapses between the photoreceptors and bipolar cells undergo rewiring and functionally compensate to maintain normal signal output to the brain.Distinct classes of retinal ganglion cells remain even after the massive loss of photoreceptors.Müller glia possess the regenerative potential for retinal recovery and possibly exert adaptive transcriptional changes in response to neuronal loss.These types of homeostatic changes could potentially explain the well-maintained visual function observed in patients with inherited retinal degenerative diseases who display prominent anatomic retinal pathology.This review will focus on our current understanding of retinal neuronal and Müller glial adaptation for the potential preservation of retinal activity during photoreceptor degeneration.Targeting retinal self-compensatory responses could help generate universal strategies to delay sensory disease progression.
基金supported by NIH/NEI R01 grants (EY031765,EY028100EY024963)+1 种基金BrightFocus Foundation,Research to Prevent Blindness Dolly Green Special Scholar AwardBoston Children’s Hospital Ophthalmology Foundation,Mass Lions Eye Research Fund Inc.(to JC)。
文摘Age-related macular degeneration is a primary cause of blindness in the older adult population. Past decades of research in the pathophysiology of the disease have resulted in breakthroughs in the form of anti-vascular endothelial growth factor therapies against neovascular age-related macular degeneration;however, effective treatment is not yet available for geographical atrophy in dry agerelated macular degeneration or for preventing the progression from early or mid to the late stage of age-related macular degeneration. Both clinical and experimental investigations involving human agerelated macular degeneration retinas and animal models point towards the atrophic alterations in retinal pigment epithelium as a key feature in age-related macular degeneration progression. Retinal pigment epithelium cells are primarily responsible for cellular-structural maintenance and nutrition supply to keep photoreceptors healthy and functional. The retinal pigment epithelium constantly endures a highly oxidative environment that is balanced with a cascade of antioxidant enzyme systems regulated by nuclear factor erythroid-2-related factor 2 as a main redox sensing transcription factor. Aging and accumulated oxidative stress triggers retinal pigment epithelium dysfunction and eventually death. Exposure to both environmental and genetic factors aggravates oxidative stress damage in aging retinal pigment epithelium and accelerates retinal pigment epithelium degeneration in age-related macular degeneration pathophysiology. The present review summarizes the role of oxidative stress in retinal pigment epithelium degeneration, with potential impacts from both genetic and environmental factors in age-related macular degeneration development and progression. Potential strategies to counter retinal pigment epithelium damage and protect the retinal pigment epithelium through enhancing its antioxidant capacity are also discussed, focusing on existing antioxidant nutritional supplementation, and exploring nuclear factor erythroid-2-related factor 2 and its regulators including REV-ERBα as therapeutic targets to protect against age-related macular degeneration development and progression.
基金supported by the National Natural Science Foundation of China,Nos.82074454(to XJC),82174409(to MY),81930116(to YJW),81873317(to XJC)the National Key R&D Program of China,No.2018YFC1704300(to YJW)the Natural Science Foundation of Shanghai,No.20ZR1459000(to MY)。
文摘Chronic spinal cord compression(CSCC)is induced by disc herniation and other reasons,leading to movement and sensation dysfunction,with a serious impact on quality of life.Spontaneous disc herniation rarely occurs in rodents,and therefore establishing a chronic spinal cord compression(CSCC)animal model is of crucial importance to explore the pathogenesis and treatment of CSCC.The absence of secreted protein,acidic,and rich in cysteine(SPARC)leads to spontaneous intervertebral disc degeneration in mice,which resembles human disc degeneration.In this study,we evaluated whether SPARC-null mice may serve as an animal model for CSCC.We performed rod rotation test,pain threshold test,gait analysis,and Basso Mouse Scale score.Our results showed that the motor function of SPARC-null mice was weakened,and magnetic resonance images revealed compression at different spinal cord levels,particularly in the lumbar segments.Immunofluorescence staining and western blot assay showed that the absence of SPARC induced apoptosis of neurons and oligodendrocytes,activation of microglia/macrophages with M1/M2 phenotype and astrocytes with A1/A2 phenotype;it also activated the expression of the NOD-like receptor protein 3 inflammasome and inhibited brain-derived neurotrophic factor/tyrosine kinase B signaling pathway.Notably,these findings are characteristics of CSCC.Therefore,we propose that SPARC-null mice may be an animal model for studying CSCC caused by disc herniation.
文摘Neurodegeneration of the central nervous system(CNS)underscores many of humanity’s most debilitating diseases,including Alzheimer’s disease,Parkinson’s disease,and multiple sclerosis.Recently,the nitric oxide-guanylate cyclase-cyclic guanosine monophosphate(NOGC-cGMP)signaling pathway has gained traction as a neuroprotective pathway in the CNS.As an extension of the CNS,the retina is also susceptible to neurodegeneration with age.The most prevalent optic neuropathy is glaucoma,the world’s leading cause of irreversible blindness,predicted to affect more than 112 million people worldwide by 2040(Calkins,2021).In glaucoma,vision loss occurs due to the progressive degeneration of retinal ganglion cells(RGCs),the output neurons of the retina,along with their axons which form the optic nerve(Wareham et al.,2022).Degeneration of RGCs leads to a characteristic pattern of scotopic visual field deficiencies that spread from one retinotopic sector to the next(Elze et al.,2015).Visual deficits are linked to increasing age and the sensitivity of RGCs to intraocular pressure(Calkins,2021).
文摘·AIM:To evaluate visual outcomes and changes in fluid after administering monthly anti-vascular endothelial growth factor(VEGF)injections to treat neovascular agerelated macular degeneration(n AMD)with subretinal fluid(SRF)and pigment epithelial detachment(PED).·METHODS:This prospective study included eyes with n AMD previously treated with as-needed anti-VEGF injections.The patients were treated with six monthly intravitreal injections of ranibizumab.Quantitative volumetric segmentation analyses of the SRF and PED were performed.The main outcome measures included best-corrected visual acuity(BCVA),and SRF and PED volumes.·RESULTS:Twenty eyes of 20 patients were included in this study.At the 6-month follow-up,BCVA and PED volume did not change significantly(P=0.110 and 0.999,respectively)but the mean SRF volume decreased from 0.53±0.82 mm3 at baseline to 0.08±0.23 mm3(P=0.002).The absorption rate of the SRF volume was negatively correlated with the duration of previous antiVEGF treatment(P=0.029).Seven of the 20 eyes(35%)showed a fluid-free macula and significant improvement in BCVA(P=0.036)by month 6.·CONCLUSION:Quantifying the SRF can precisely determine the patient’s responsiveness to anti-VEGF treatment of n AMD.
文摘Age-related macular degeneration is a major global cause of central visual impairment and seve re vision loss.With an aging population,the already immense economic burden of costly anti-vascular endothelial growth fa ctor treatment is likely to increase.In addition,current conventional treatment is only available for the late neovascular stage of age-related macular degeneration,and injections can come with potentially devastating complications,introducing the need for more economical and ris kfree treatment.In recent years,exosomes,which are nano-sized extracellular vesicles of an endocytic origin,have shown immense potential as diagnostic biomarkers and in the therapeutic application,as they are bestowed with characte ristics including an expansive cargo that closely resembles their parent cell and exceptional ability of intercellular communication and targeting neighboring cells.Exosomes are currently undergoing clinical trials for various conditions such as type 1 diabetes and autoimmune diseases;however,exosomes as a potential therapy for seve ral retinal diseases have just begun to undergo scrutinizing investigation with little literature on age-related macular degeneration specifically.This article will focus on the limited literature availa ble on exosome transplantation treatment in age-related macular degeneration animal models and in vitro cell cultures,as well as briefly identify future research directions.Current literature on exosome therapy using agerelated macular degeneration rodent models includes laser retinal injury,N-methyl-N-nitrosourea,and royal college of surgeon models,which mimic inflammatory and degenerative aspects of agerelated macular degeneration.These have shown promising results in preserving retinal function and morphology,as well as protecting photoreceptors from apoptosis.Exosomes from their respective cellular origins may also act by regulating the expression of various inflammatory cyto kines,mRNAs,and proteins involved in photo receptor degeneration pathways to exert a therapeutic effect.Various findings have also opened exciting prospects for the involvement of cargo components in remedial effects on the damaged macula or retina.
基金supported by the Notional Natural Science Foundation of China,Nos.81770918 (to ZLC),31871383 (to TL)the Natural Science Foundation of Zhejiang Province,No.LY16H120006 (to ZLC)the Departmental Funds from Wenzhou Medical University,No.89214018 (to ZLC)。
文摘Slit-Robo GTPase-activating protein 2(SRGAP2) plays important roles in axon guidance, neuronal migration, synapse formation, and nerve regeneration. However, the role of SRGAP2 in neuroretinal degenerative disease remains unclear. In this study, we found that SRGAP2 protein was first expressed in the retina of normal mice at the embryonic stage and was mainly located in the mature retinal ganglion cell layer and the inner nuclear layer. SRGAP2 protein in the retina and optic nerve increased after optic nerve crush. Then, we established a heterozygous knockout(Srgap2+/–) mouse model of optic nerve crush and found that Srgap2 suppression increased retinal ganglion cell survival, lowered intraocular pressure, inhibited glial cell activation, and partially restored retinal function. In vitro experiments showed that Srgap2 suppression activated the mammalian target of rapamycin signaling pathway. RNA sequencing results showed that the expression of small heat shock protein genes(Cryaa, Cryba4, and Crygs) related to optic nerve injury were upregulated in the retina of Srgap2+/– mice. These results suggest that Srgap2 suppression reduced the robust activation of glial cells, activated the mammalian target of rapamycin signaling pathway related to nerve protein, increased the expression of small heat shock protein genes, inhibited the degeneration of retinal ganglion cells, and partially restored optic nerve function.
基金the Ministry of Science and Technology China Brain Initiative Grant,No.2022ZD0204701the National Natural Science Foundation of China,Nos.82071386&81870982(all to JG)。
文摘Dendrites play irreplaceable roles in the nerve conduction pathway and are vulnerable to various insults.Peripheral axotomy of motor neurons results in the retraction of dendritic arbors,and the dendritic arbor can be re-expanded when reinnervation is allowed.RhoA is a target that regulates the cytoskeleton and promotes neuronal survival and axon regeneration.However,the role of RhoA in dendrite degeneration and regeneration is unknown.In this study,we explored the potential role of RhoA in dendrites.A line of motor neuronal conditional knockout mice was developed by crossbreeding HB9~(Cre+)mice with RhoA~(flox/flox)mice.We established two models for assaying dendrite degeneration and regeneration,in which the brachial plexus was transection or crush injured,respectively.We found that at 28 days after brachial plexus transection,the density,complexity,and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice were slightly decreased compared with that in Cre mice.Dendrites underwent degeneration at 7 and 14 days after brachial plexus transection and recovered at 28–56 days.The density,complexity,and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice recovered compared with results in Cre mice.These findings suggest that RhoA knockout in motor neurons attenuates dendrite degeneration and promotes dendrite regeneration after peripheral nerve injury.
文摘Neurite degeneration,a major component of many neurodegenerative diseases,such as Parkinson’s disease,Alzheimer’s disease,and amyotrophic lateral sclerosis,is not part of the typical apoptosis signaling mechanism,but rather it appears that a self-destructive process is in action.Oxidative stress is a well-known inducer of neurodegenerative pathways:neuronal cell death and neurite degeneration.Although oxidative stress exerts cytotoxic effects leading to neuronal loss,the pathogenic mechanisms and precise signaling pathways by which oxidative stress causes neurite degeneration have remained entirely unknown.We previously reported that reactive oxygen species generated by NADPH oxidases induce activation of the E3 ubiquitin ligase ZNRF1 in neurons,which promotes neurite degeneration.In this process,the phosphorylation of an NADPH oxidase subunit p47-phox at the 345serine residue serves as an important checkpoint to initiate the ZNRF1-dependent neurite degeneration.Evidence provides new insights into the mechanism of reactive oxygen species-mediated neurodegeneration.In this review,we focus specifically on reactive oxygen species-induced neurite degeneration by highlighting a phosphorylation-dependent regulation of the molecular interaction between ZNRF1 and the NADPH oxidase complex.
文摘Vision is one of our most precious senses,and its impairment has a high socio-economic impact.In the industrialized world,degenerative diseases of the retina lead to vision loss,particularly among the elderly.These degenerations include,for instance,retinitis pigmentosa,age-related macular degeneration,and diabetic retinopathy.Although treatments are evolving to manage late-stage symptoms of retinal degenerations,no effective therapies to recover vision loss exist.Retinal degeneration often involves loss or damage to specialized neural cells,such as photoreceptors,and their death stimulates the activation and proliferation of Müller cells(Salman et al.,2021).
基金partially supported by R01NS117102 from the National Institutes of Health (NIH)Maryland Stem Cell Research Fund (2020-MSCRFD-5384), USA (both to XJ)
文摘Peripheral nerve injury(PNI)causes sensory and motor deficits as well as neuropathic pain,which seriously impacts patient quality of life(Jiang et al.,2017).Morphological and molecular changes in the spinal cord and dorsal root ganglia(DRG),such as neuronal cell death,nerve fiber degeneration,and glial activation,are strongly associated with PNI-induced pathological syndromes.
基金Bright Focus FoundationUChicago Women's Board+3 种基金ISPBUChicago ITMGenentech ARVO FoundationFORE-I Foundation (to DS)。
文摘Age-related macular degeneration(AMD) is the most common cause of blindness in the United States in adults over 55 years of age and is one of the leading global causes of blindness: at least 196 million of the worldwide population have AMD, and prevalence is projected to rise to 288 million by 2040(Lin et al., 2021). As cases and disease burden increase, improvements in the characterization of AMD pathobiology and exploration of potential therapeutic solutions are necessary first steps in addressing this global health concern.
