Loading...

Table of Content

    15 February 2024, Volume 19 Issue 2 Previous Issue   
    For Selected: Toggle Thumbnails
    Advantages of nanocarriers for basic research in the field of traumatic brain injury
    Xingshuang Song, Yizhi Zhang, Ziyan Tang, Lina Du
    2024, 19 (2):  237-245.  doi: 10.4103/1673-5374.379041
    Abstract ( 159 )   PDF (1444KB) ( 159 )   Save
    A major challenge for the efficient treatment of traumatic brain injury is the need for therapeutic molecules to cross the blood-brain barrier to enter and accumulate in brain tissue. To overcome this problem, researchers have begun to focus on nanocarriers and other brain-targeting drug delivery systems. In this review, we summarize the epidemiology, basic pathophysiology, current clinical treatment, the establishment of models, and the evaluation indicators that are commonly used for traumatic brain injury. We also report the current status of traumatic brain injury when treated with nanocarriers such as liposomes and vesicles. Nanocarriers can overcome a variety of key biological barriers, improve drug bioavailability, increase intracellular penetration and retention time, achieve drug enrichment, control drug release, and achieve brain-targeting drug delivery. However, the application of nanocarriers remains in the basic research stage and has yet to be fully translated to the clinic.
    Related Articles | Metrics
    Transcriptional regulation in the development and dysfunction of neocortical projection neurons
    Ningxin Wang, Rong Wan, Ke Tang
    2024, 19 (2):  246-254.  doi: 10.4103/1673-5374.379039
    Abstract ( 491 )   PDF (893KB) ( 446 )   Save
    Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas, and between the neocortex and other regions of the brain and spinal cord. Appropriate development of cortical projection neurons is regulated by certain essential events such as neural fate determination, proliferation, specification, differentiation, migration, survival, axonogenesis, and synaptogenesis. These processes are precisely regulated in a tempo-spatial manner by intrinsic factors, extrinsic signals, and neural activities. The generation of correct subtypes and precise connections of projection neurons is imperative not only to support the basic cortical functions (such as sensory information integration, motor coordination, and cognition) but also to prevent the onset and progression of neurodevelopmental disorders (such as intellectual disability, autism spectrum disorders, anxiety, and depression). This review mainly focuses on the recent progress of transcriptional regulations on the development and diversity of neocortical projection neurons and the clinical relevance of the failure of transcriptional modulations.
    Related Articles | Metrics
    Adenosine A2A receptor blockade attenuates excitotoxicity in rat striatal medium spiny neurons during an ischemic-like insult
    Elisabetta Coppi, Federica Cherchi, Alasdair J. Gibb
    2024, 19 (2):  255-257.  doi: 10.4103/1673-5374.375309
    Abstract ( 115 )   PDF (563KB) ( 160 )   Save

    During brain ischemia, excitotoxicity and peri-infarct depolarization injuries occur and cause cerebral tissue damage. Indeed, anoxic depolarization, consisting of massive neuronal depolarization due to the loss of membrane ion gradients, occurs in vivo or in vitro during an energy failure. The neuromodulator adenosine is released in huge amounts during cerebral ischemia and exerts its effects by activating specific metabotropic receptors, namely: A1, A2A, A2B, and A3. The A2A receptor subtype is highly expressed in striatal medium spiny neurons, which are particularly susceptible to ischemic damage. Evidence indicates that the A2A receptors are upregulated in the rat striatum after stroke and the selective antagonist SCH58261 protects from exaggerated glutamate release within the first 4 hours from the insult and alleviates neurological impairment and histological injury in the following 24 hours. We recently added new knowledge to the mechanisms by which the adenosine A2A receptor subtype participates in ischemia-induced neuronal death by performing patch-clamp recordings from medium spiny neurons in rat striatal brain slices exposed to oxygen and glucose deprivation. We demonstrated that the selective block of A2A receptors by SCH58261 significantly reduced ionic imbalance and delayed the anoxic depolarization in medium spiny neurons during oxygen and glucose deprivation and that the mechanism involves voltage-gated K+ channel modulation and a presynaptic inhibition of glutamate release by the A2A receptor antagonist. The present review summarizes the latest findings in the literature about the possibility of developing selective ligands of A2A receptors as advantageous therapeutic tools that may contribute to counteracting neurodegeneration after brain ischemia.

    Related Articles | Metrics
    Recent advances in the application of MXenes for neural tissue engineering and regeneration
    Menghui Liao, Qingyue Cui, Yangnan Hu, Jiayue Xing, Danqi Wu, Shasha Zheng, Yu Zhao, Yafeng Yu, Jingwu Sun, Renjie Chai
    2024, 19 (2):  258-263.  doi: 10.4103/1673-5374.379037
    Abstract ( 200 )   PDF (1628KB) ( 105 )   Save
    Transition metal carbides and nitrides (MXenes) are crystal nanomaterials with a number of surface functional groups such as fluorine, hydroxyl, and oxygen, which can be used as carriers for proteins and drugs. MXenes have excellent biocompatibility, electrical conductivity, surface hydrophilicity, mechanical properties and easy surface modification. However, at present, the stability of most MXenes needs to be improved, and more synthesis methods need to be explored. MXenes are good substrates for nerve cell regeneration and nerve reconstruction, which have broad application prospects in the repair of nervous system injury. Regarding the application of MXenes in neuroscience, mainly at the cellular level, the long-term in vivo biosafety and effects also need to be further explored. This review focuses on the progress of using MXenes in nerve regeneration over the last few years; discussing preparation of MXenes and their biocompatibility with different cells as well as the regulation by MXenes of nerve cell regeneration in two-dimensional and three-dimensional environments in vitro. MXenes have great potential in regulating the proliferation, differentiation, and maturation of nerve cells and in promoting regeneration and recovery after nerve injury. In addition, this review also presents the main challenges during optimization processes, such as the preparation of stable MXenes and long-term in vivo biosafety, and further discusses future directions in neural tissue engineering.
    Related Articles | Metrics
    Role of lipids in the control of autophagy and primary cilium signaling in neurons
    María Paz Hernández-Cáceres, Daniela Pinto-Nuñez, Patricia Rivera, Paulina Burgos, Francisco Díaz-Castro, Alfredo Criollo, Maria Jose Yañez, Eugenia Morselli
    2024, 19 (2):  264-271.  doi: 10.4103/1673-5374.377414
    Abstract ( 128 )   PDF (1153KB) ( 95 )   Save
    The brain is, after the adipose tissue, the organ with the greatest amount of lipids and diversity in their composition in the human body. In neurons, lipids are involved in signaling pathways controlling autophagy, a lysosome-dependent catabolic process essential for the maintenance of neuronal homeostasis and the function of the primary cilium, a cellular antenna that acts as a communication hub that transfers extracellular signals into intracellular responses required for neurogenesis and brain development. A crosstalk between primary cilia and autophagy has been established; however, its role in the control of neuronal activity and homeostasis is barely known. In this review, we briefly discuss the current knowledge regarding the role of autophagy and the primary cilium in neurons. Then we review the recent literature about specific lipid subclasses in the regulation of autophagy, in the control of primary cilium structure and its dependent cellular signaling in physiological and pathological conditions, specifically focusing on neurons, an area of research that could have major implications in neurodevelopment, energy homeostasis, and neurodegeneration.
    Related Articles | Metrics
    Gut microbial regulation of innate and adaptive immunity after traumatic brain injury
    Marta Celorrio, Kirill Shumilov, Stuart H. Friess
    2024, 19 (2):  272-276.  doi: 10.4103/1673-5374.379014
    Abstract ( 114 )   PDF (593KB) ( 112 )   Save
    Acute care management of traumatic brain injury is focused on the prevention and reduction of secondary insults such as hypotension, hypoxia, intracranial hypertension, and detrimental inflammation. However, the imperative to balance multiple clinical concerns simultaneously often results in therapeutic strategies targeted to address one clinical concern causing unintended effects in other remote organ systems. Recently the bidirectional communication between the gastrointestinal tract and the brain has been shown to influence both the central nervous system and gastrointestinal tract homeostasis in health and disease. A critical component of this axis is the microorganisms of the gut known as the gut microbiome. Changes in gut microbial populations in the setting of central nervous system disease, including traumatic brain injury, have been reported in both humans and experimental animal models and can be further disrupted by off-target effects of patient care. In this review article, we will explore the important role gut microbial populations play in regulating brain-resident and peripheral immune cell responses after traumatic brain injury. We will discuss the role of bacterial metabolites in gut microbial regulation of neuroinflammation and their potential as an avenue for therapeutic intervention in the setting of traumatic brain injury.
    Related Articles | Metrics
    Myelin histology: a key tool in nervous system research
    Óscar Darío García-García, Víctor Carriel, Jesús Chato-Astrain
    2024, 19 (2):  277-281.  doi: 10.4103/1673-5374.375318
    Abstract ( 112 )   PDF (1410KB) ( 49 )   Save
    The myelin sheath is a lipoprotein-rich, multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve fibers. Due to the complex structure and composition of myelin, various histological techniques have been developed over the centuries to evaluate myelin under normal, pathological or experimental conditions. Today, methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience research. In this review, we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures, from tissue fixation and processing techniques to the most used and practical myelin histological staining methods. Considering the lipoprotein nature of myelin, the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described, as well as the precise ultrastructural techniques.
    Related Articles | Metrics
    The role of exosomes in adult neurogenesis: implications for neurodegenerative diseases
    Zhuoyang Yu, Yan Teng, Jing Yang, Lu Yang
    2024, 19 (2):  282-288.  doi: 10.4103/1673-5374.379036
    Abstract ( 339 )   PDF (1178KB) ( 216 )   Save
    Exosomes are cup-shaped extracellular vesicles with a lipid bilayer that is approximately 30 to 200 nm in thickness. Exosomes are widely distributed in a range of body fluids, including urine, blood, milk, and saliva. Exosomes exert biological function by transporting factors between different cells and by regulating biological pathways in recipient cells. As an important form of intercellular communication, exosomes are increasingly being investigated due to their ability to transfer bioactive molecules such as lipids, proteins, mRNAs, and microRNAs between cells, and because they can regulate physiological and pathological processes in the central nervous system. Adult neurogenesis is a multistage process by which new neurons are generated and migrate to be integrated into existing neuronal circuits. In the adult brain, neurogenesis is mainly localized in two specialized niches: the subventricular zone adjacent to the lateral ventricles and the subgranular zone of the dentate gyrus. An increasing body of evidence indicates that adult neurogenesis is tightly controlled by environmental conditions with the niches. In recent studies, exosomes released from different sources of cells were shown to play an active role in regulating neurogenesis both in vitro and in vivo, thereby participating in the progression of neurodegenerative disorders in patients and in various disease models. Here, we provide a state-of-the-art synopsis of existing research that aimed to identify the diverse components of exosome cargoes and elucidate the therapeutic potential of exosomal contents in the regulation of neurogenesis in several neurodegenerative diseases. We emphasize that exosomal cargoes could serve as a potential biomarker to monitor functional neurogenesis in adults. In addition, exosomes can also be considered as a novel therapeutic approach to treat various neurodegenerative disorders by improving endogenous neurogenesis to mitigate neuronal loss in the central nervous system.
    Related Articles | Metrics
    Novel insights into D-Pinitol based therapies: a link between tau hyperphosphorylation and insulin resistance
    Dina Medina-Vera, Antonio Jesús López-Gambero, Juan Antonio Navarro, Carlos Sanjuan, Elena Baixeras, Juan Decara, Fernando Rodríguez de Fonseca
    2024, 19 (2):  289-295.  doi: 10.4103/1673-5374.379015
    Abstract ( 114 )   PDF (1717KB) ( 45 )   Save
    Alzheimer’s disease is a neurodegenerative disorder characterized by the amyloid accumulation in the brains of patients with Alzheimer’s disease. The pathogenesis of Alzheimer’s disease is mainly mediated by the phosphorylation and aggregation of tau protein. Among the multiple causes of tau hyperphosphorylation, brain insulin resistance has generated much attention, and inositols as insulin sensitizers, are currently considered candidates for drug development. The present narrative review revises the interactions between these three elements: Alzheimer’s disease-tau-inositols, which can eventually identify targets for new disease modifiers capable of bringing hope to the millions of people affected by this devastating disease.
    Related Articles | Metrics
    The dorsal root ganglion as a target for neurorestoration in neuropathic pain
    Guillermo Estivill-Torrús, Ana Belen Martínez-Padilla, Lourdes Sánchez-Salido, Anne Baron-Van Evercooren, Beatriz García-Díaz
    2024, 19 (2):  296-301.  doi: 10.4103/1673-5374.374655
    Abstract ( 110 )   PDF (502KB) ( 52 )   Save
    Neuropathic pain is a severe and chronic condition widely found in the general population. The reason for this is the extensive variety of damage or diseases that can spark this unpleasant constant feeling in patients. During the processing of pain, the dorsal root ganglia constitute an important region where dorsal root ganglion neurons play a crucial role in the transmission and propagation of sensory electrical stimulation. Furthermore, the dorsal root ganglia have recently exhibited a regenerative capacity that should not be neglected in the understanding of the development and resolution of neuropathic pain and in the elucidation of innovative therapies. Here, we will review the complex interplay between cells (satellite glial cells and inflammatory cells) and factors (cytokines, neurotrophic factors and genetic factors) that takes place within the dorsal root ganglia and accounts for the generation of the aberrant excitation of primary sensory neurons occurring in neuropathic pain. More importantly, we will summarize an updated view of the current pharmacologic and nonpharmacologic therapies targeting the dorsal root ganglia for the treatment of neuropathic pain.
    Related Articles | Metrics
    5-Bromo-2'-deoxyuridine labeling: historical perspectives, factors influencing the detection, toxicity, and its implications in the neurogenesis
    Joaquín Martí-Clúa
    2024, 19 (2):  302-308.  doi: 10.4103/1673-5374.379038
    Abstract ( 147 )   PDF (935KB) ( 55 )   Save
    The halopyrimidine 5-bromo-2′-deoxyuridine (BrdU) is an exogenous marker of DNA synthesis. Since the introduction of monoclonal antibodies against BrdU, an increasing number of methodologies have been used for the immunodetection of this synthesized bromine-tagged base analogue into replicating DNA. BrdU labeling is widely used for identifying neuron precursors and following their fate during the embryonic, perinatal, and adult neurogenesis in a variety of vertebrate species including birds, reptiles, and mammals. Due to BrdU toxicity, its incorporation into replicating DNA presents adverse consequences on the generation, survival, and settled patterns of cells. This may lead to false results and misinterpretation in the identification of proliferative neuroblasts. In this review, I will indicate the detrimental effects of this nucleoside during the development of the central nervous system, as well as the reliability of BrdU labeling to detect proliferating neuroblasts. Moreover, it will show factors influencing BrdU immunodetection and the contribution of this nucleoside to the study of prenatal, perinatal, and adult neurogenesis. Human adult neurogenesis will also be discussed. It is my hope that this review serves as a reference for those researchers who focused on detecting cells that are in the synthetic phase of the cell cycle.
    Related Articles | Metrics
    The roles of macrophage migration inhibitory factor in retinal diseases
    Hongbing Zhang, Xianjiao Zhang, Hongsong Li, Bing Wang, Pei Chen, Jiamin Meng
    2024, 19 (2):  309-315.  doi: 10.4103/1673-5374.379020
    Abstract ( 198 )   PDF (1252KB) ( 77 )   Save

    Macrophage migration inhibitory factor (MIF), a multifunctional cytokine, is secreted by various cells and participates in inflammatory reactions, including innate and adaptive immunity. There are some evidences that MIF is involved in many vitreoretinal diseases. For example, MIF can exacerbate many types of uveitis; measurements of MIF levels can be used to monitor the effectiveness of uveitis treatment. MIF also alleviates trauma-induced and glaucoma-induced optic nerve damage. Furthermore, MIF is critical for retinal/choroidal neovascularization, especially complex neovascularization. MIF exacerbates retinal degeneration; thus, anti-MIF therapy may help to mitigate retinal degeneration. MIF protects uveal melanoma from attacks by natural killer cells. The mechanism underlying the effects of MIF in these diseases has been demonstrated: it binds to cluster of differentiation 74, inhibits the c-Jun N-terminal kinase pathway, and triggers mitogen-activated protein kinases, extracellular signal-regulated kinase-1/2, and the phosphoinositide-3-kinase/Akt pathway. MIF also upregulates Toll-like receptor 4 and activates the nuclear factor kappa-B signaling pathway. This review focuses on the structure and function of MIF and its receptors, including the effects of MIF on uveal inflammation, retinal degeneration, optic neuropathy, retinal/choroidal neovascularization, and uveal melanoma.

    Related Articles | Metrics
    Mitophagy in intracerebral hemorrhage: a new target for therapeutic intervention
    Yiyang Chen, Wenxuan Tang, Xinqi Huang, Yumei An, Jiawen Li, Shengye Yuan, Haiyan Shan, Mingyang Zhang
    2024, 19 (2):  316-323.  doi: 10.4103/1673-5374.379019
    Abstract ( 299 )   PDF (874KB) ( 132 )   Save
    Intracerebral hemorrhage is a life-threatening condition with a high fatality rate and severe sequelae. However, there is currently no treatment available for intracerebral hemorrhage, unlike for other stroke subtypes. Recent studies have indicated that mitochondrial dysfunction and mitophagy likely relate to the pathophysiology of intracerebral hemorrhage. Mitophagy, or selective autophagy of mitochondria, is an essential pathway to preserve mitochondrial homeostasis by clearing up damaged mitochondria. Mitophagy markedly contributes to the reduction of secondary brain injury caused by mitochondrial dysfunction after intracerebral hemorrhage. This review provides an overview of the mitochondrial dysfunction that occurs after intracerebral hemorrhage and the underlying mechanisms regarding how mitophagy regulates it, and discusses the new direction of therapeutic strategies targeting mitophagy for intracerebral hemorrhage, aiming to determine the close connection between mitophagy and intracerebral hemorrhage and identify new therapies to modulate mitophagy after intracerebral hemorrhage. In conclusion, although only a small number of drugs modulating mitophagy in intracerebral hemorrhage have been found thus far, most of which are in the preclinical stage and require further investigation, mitophagy is still a very valid and promising therapeutic target for intracerebral hemorrhage in the long run.
    Related Articles | Metrics
    A review of the neurotransmitter system associated with cognitive function of the cerebellum in Parkinson’s disease
    Xi Chen, Yuhu Zhang
    2024, 19 (2):  324-330.  doi: 10.4103/1673-5374.379042
    Abstract ( 253 )   PDF (989KB) ( 115 )   Save
    The dichotomized brain system is a concept that was generalized from the ‘dual syndrome hypothesis’ to explain the heterogeneity of cognitive impairment, in which anterior and posterior brain systems are independent but partially overlap. The dopaminergic system acts on the anterior brain and is responsible for executive function, working memory, and planning. In contrast, the cholinergic system acts on the posterior brain and is responsible for semantic fluency and visuospatial function. Evidence from dopaminergic/cholinergic imaging or functional neuroimaging has shed significant insight relating to the involvement of the cerebellum in the cognitive process of patients with Parkinson’s disease. Previous research has reported evidence that the cerebellum receives both dopaminergic and cholinergic projections. However, whether these two neurotransmitter systems are associated with cognitive function has yet to be fully elucidated. Furthermore, the precise role of the cerebellum in patients with Parkinson’s disease and cognitive impairment remains unclear. Therefore, in this review, we summarize the cerebellar dopaminergic and cholinergic projections and their relationships with cognition, as reported by previous studies, and investigated the role of the cerebellum in patients with Parkinson’s disease and cognitive impairment, as determined by functional neuroimaging. Our findings will help us to understand the role of the cerebellum in the mechanisms underlying cognitive impairment in Parkinson’s disease.
    Related Articles | Metrics
    Recent progress and future directions of the research on nanoplastic-induced neurotoxicity
    Seung-Woo Han, Jinhee Choi, Kwon-Yul Ryu
    2024, 19 (2):  331-335.  doi: 10.4103/1673-5374.379016
    Abstract ( 206 )   PDF (798KB) ( 134 )   Save
    Many types of plastic products, including polystyrene, have long been used in commercial and industrial applications. Microplastics and nanoplastics, plastic particles derived from these plastic products, are emerging as environmental pollutants that can pose health risks to a wide variety of living organisms, including humans. However, it is not well understood how microplastics and nanoplastics affect cellular functions and induce stress responses. Humans can be exposed to polystyrene-microplastics and polystyrene-nanoplastics through ingestion, inhalation, or skin contact. Most ingested plastics are excreted from the body, but inhaled plastics may accumulate in the lungs and can even reach the brain via the nose-to-brain route. Small-sized polystyrene-nanoplastics can enter cells by endocytosis, accumulate in the cytoplasm, and cause various cellular stresses, such as inflammation with increased pro-inflammatory cytokine production, oxidative stress with generation of reactive oxygen species, and mitochondrial dysfunction. They induce autophagy activation and autophagosome formation, but autophagic flux may be impaired due to lysosomal dysfunction. Unless permanently exposed to polystyrene-nanoplastics, they can be removed from cells by exocytosis and subsequently restore cellular function. However, neurons are very susceptible to this type of stress, thus even acute exposure can lead to neurodegeneration without recovery. This review focuses specifically on recent advances in research on polystyrene-nanoplastic-induced cytotoxicity and neurotoxicity. Furthermore, in this review, based on mechanistic studies of polystyrene-nanoplastics at the cellular level other than neurons, future directions for overcoming the negative effects of polystyrene-nanoplastics on neurons were suggested.
    Related Articles | Metrics
    Adverse effects of early-life stress: focus on the rodent neuroendocrine system
    Seung Hyun Lee, Eui-Man Jung
    2024, 19 (2):  336-341.  doi: 10.4103/1673-5374.377587
    Abstract ( 123 )   PDF (694KB) ( 90 )   Save
    Early-life stress is associated with a high prevalence of mental illnesses such as post-traumatic stress disorders, attention-deficit/hyperactivity disorder, schizophrenia, and anxiety or depressive behavior, which constitute major public health problems. In the early stages of brain development after birth, events such as synaptogenesis, neuron maturation, and glial differentiation occur in a highly orchestrated manner, and external stress can cause adverse long-term effects throughout life. Our body utilizes multifaceted mechanisms, including neuroendocrine and neurotransmitter signaling pathways, to appropriately process external stress. Newborn individuals first exposed to early-life stress deploy neurogenesis as a stress-defense mechanism; however, in adulthood, early-life stress induces apoptosis of mature neurons, activation of immune responses, and reduction of neurotrophic factors, leading to anxiety, depression, and cognitive and memory dysfunction. This process involves the hypothalamus-pituitary-adrenal axis and neurotransmitters secreted by the central nervous system, including norepinephrine, dopamine, and serotonin. The rodent early-life stress model is generally used to experimentally assess the effects of stress during neurodevelopment. This paper reviews the use of the early-life stress model and stress response mechanisms of the body and discusses the experimental results regarding how early-life stress mediates stress-related pathways at a high vulnerability of psychiatric disorder in adulthood.
    Related Articles | Metrics
    Physiological and pathological functions of circular RNAs in the nervous system
    Min Zhou, Shi Li, Chuan Huang
    2024, 19 (2):  342-349.  doi: 10.4103/1673-5374.379017
    Abstract ( 134 )   PDF (1309KB) ( 87 )   Save
    Circular RNAs (circRNAs) are a class of covalently closed single-stranded RNAs that are expressed during the development of specific cells and tissues. CircRNAs play crucial roles in physiological and pathological processes by sponging microRNAs, modulating gene transcription, controlling the activity of certain RNA-binding proteins, and producing functional peptides. A key focus of research at present is the functionality of circRNAs in the nervous system and several advances have emerged over the last 2 years. However, the precise role of circRNAs in the nervous system has yet to be comprehensively reviewed. In this review, we first summarize the recently described roles of circRNAs in brain development, maturity, and aging. Then, we focus on the involvement of circRNAs in various diseases of the central nervous system, such as brain cancer, chronic neurodegenerative diseases, acute injuries of the nervous system, and neuropathic pain. A better understanding of the functionality of circRNAs will help us to develop potential diagnostic, prognostic, and therapeutic strategies to treat diseases of the nervous system.
    Related Articles | Metrics
    Role of N-formyl peptide receptor 2 in germinal matrix hemorrhage: an intrinsic review of a hematoma resolving pathway
    Jerry Flores, Jiping Tang
    2024, 19 (2):  350-354.  doi: 10.4103/1673-5374.379040
    Abstract ( 114 )   PDF (586KB) ( 42 )   Save
    Germinal matrix hemorrhage is one of the leading causes of morbidity, mortality, and acquired infantile hydrocephalus in preterm infants in the United States, with little progress made in its clinical management. Blood clots have been shown to elicit secondary brain injury after germinal matrix hemorrhage, by disrupting normal cerebrospinal fluid circulation and absorption after germinal matrix hemorrhage causing post-hemorrhagic hydrocephalus development. Current evidence suggests that rapid hematoma resolution is necessary to improve neurological outcomes after hemorrhagic stroke. Various articles have demonstrated the beneficial effects of stimulating the polarization of microglia cells into the M2 phenotype, as it has been suggested that they play an essential role in the rapid phagocytosis of the blood clot after hemorrhagic models of stroke. N-formyl peptide receptor 2 (FPR2), a G-protein-coupled receptor, has been shown to be neuroprotective after stroke. FPR2 activation has been associated with the upregulation of phagocytic macrophage clearance, yet its mechanism has not been fully explored. Recent literature suggests that FPR2 may play a role in the stimulation of scavenger receptor CD36. Scavenger receptor CD36 plays a vital role in microglia phagocytic blood clot clearance after germinal matrix hemorrhage. FPR2 has been shown to phosphorylate extracellular-signal-regulated kinase 1/2 (ERK1/2), which then promotes the transcription of the dual-specificity protein phosphatase 1 (DUSP1) gene. In this review, we present an intrinsic outline of the main components involved in FPR2 stimulation and hematoma resolution after germinal matrix hemorrhage. 
    Related Articles | Metrics
    Mucopolysaccharidosis type IIIB: a current review and exploration of the AAV therapy landscape
    Courtney J. Rouse, Victoria N. Jensen, Coy D. Heldermon
    2024, 19 (2):  355-359.  doi: 10.4103/1673-5374.377606
    Abstract ( 116 )   PDF (858KB) ( 84 )   Save
    Mucopolysaccharidoses type IIIB is a rare genetic disorder caused by mutations in the gene that encodes for N-acetyl-alpha-glucosaminidase. This results in the aggregation of heparan sulfate polysaccharides within cell lysosomes that leads to progressive and severe debilitating neurological dysfunction. Current treatment options are expensive, limited, and presently there are no approved cures for mucopolysaccharidoses type IIIB. Adeno-associated virus gene therapy has significantly advanced the field forward, allowing researchers to successfully design, enhance, and improve potential cures. Our group recently published an effective treatment using a codon-optimized triple mutant adeno-associated virus 8 vector that restores N-acetyl-alpha-glucosaminidase levels, auditory function, and lifespan in the murine model for mucopolysaccharidoses type IIIB to that seen in healthy mice. Here, we review the current state of the field in relation to the capsid landscape, adeno-associated virus gene therapy and its successes and challenges in the clinic, and how novel adeno-associated virus capsid designs have evolved research in the mucopolysaccharidoses type IIIB field.
    Related Articles | Metrics
    Metabotropic glutamate receptors (mGluRs) in epileptogenesis: an update on abnormal mGluRs signaling and its therapeutic implications
    Leyi Huang, Wenjie Xiao, Yan Wang, Juan Li, Jiaoe Gong, Ewen Tu, Lili Long, Bo Xiao, Xiaoxin Yan, Lily Wan
    2024, 19 (2):  360-368.  doi: 10.4103/1673-5374.379018
    Abstract ( 148 )   PDF (743KB) ( 80 )   Save
    Epilepsy is a neurological disorder characterized by high morbidity, high recurrence, and drug resistance. Enhanced signaling through the excitatory neurotransmitter glutamate is intricately associated with epilepsy. Metabotropic glutamate receptors (mGluRs) are G protein-coupled receptors activated by glutamate and are key regulators of neuronal and synaptic plasticity. Dysregulated mGluR signaling has been associated with various neurological disorders, and numerous studies have shown a close relationship between mGluRs expression/activity and the development of epilepsy. In this review, we first introduce the three groups of mGluRs and their associated signaling pathways. Then, we detail how these receptors influence epilepsy by describing the signaling cascades triggered by their activation and their neuroprotective or detrimental roles in epileptogenesis. In addition, strategies for pharmacological manipulation of these receptors during the treatment of epilepsy in experimental studies is also summarized. We hope that this review will provide a foundation for future studies on the development of mGluR-targeted antiepileptic drugs.
    Related Articles | Metrics
    Advances in extracellular vesicle-based combination therapies for spinal cord injury
    Tingting Wang, Guohao Huang, Zhiheng Yi, Sihan Dai, Weiduan Zhuang, Shaowei Guo
    2024, 19 (2):  369-374.  doi: 10.4103/1673-5374.377413
    Abstract ( 401 )   PDF (1173KB) ( 203 )   Save
    Spinal cord injury is a severe insult to the central nervous system that causes persisting neurological deficits. The currently available treatments involve surgical, medical, and rehabilitative strategies. However, none of these techniques can markedly reverse neurological deficits. Recently, extracellular vesicles from various cell sources have been applied to different models of spinal cord injury, thereby generating new cell-free therapies for the treatment of spinal cord injury. However, the use of extracellular vesicles alone is still associated with some notable shortcomings, such as their uncertainty in targeting damaged spinal cord tissues and inability to provide structural support to damaged axons. Therefore, this paper reviews the latest combined strategies for the use of extracellular vesicle-based technology for spinal cord injury, including the combination of extracellular vesicles with nanoparticles, exogenous drugs and/or biological scaffold materials, which facilitate the targeting ability of extracellular vesicles and the combinatorial effects with extracellular vesicles. We also highlight issues relating to the clinical transformation of these extracellular vesicle-based combination strategies for the treatment of spinal cord injury. 
    Related Articles | Metrics
    Connecting neurodevelopment to neurodegeneration: a spotlight on the role of kinesin superfamily protein 2A (KIF2A)
    Nuria Ruiz-Reig, Janne Hakanen, Fadel Tissir
    2024, 19 (2):  375-379.  doi: 10.4103/1673-5374.375298
    Abstract ( 137 )   PDF (553KB) ( 97 )   Save
    Microtubules play a central role in cytoskeletal changes during neuronal development and maintenance. Microtubule dynamics is essential to polarity and shape transitions underlying neural cell division, differentiation, motility, and maturation. Kinesin superfamily protein 2A is a member of human kinesin 13 gene family of proteins that depolymerize and destabilize microtubules. In dividing cells, kinesin superfamily protein 2A is involved in mitotic progression, spindle assembly, and chromosome segregation. In postmitotic neurons, it is required for axon/dendrite specification and extension, neuronal migration, connectivity, and survival. Humans with kinesin superfamily protein 2A mutations suffer from a variety of malformations of cortical development, epilepsy, autism spectrum disorder, and neurodegeneration. In this review, we discuss how kinesin superfamily protein 2A regulates neuronal development and function, and how its deregulation causes neurodevelopmental and neurological disorders.
    Related Articles | Metrics
    Role of transforming growth factor-β in peripheral nerve regeneration
    Zihan Ding, Maorong Jiang, Jiaxi Qian, Dandan Gu, Huiyuan Bai, Min Cai, Dengbing Yao
    2024, 19 (2):  380-386.  doi: 10.4103/1673-5374.377588
    Abstract ( 176 )   PDF (1104KB) ( 111 )   Save
    Injuries caused by trauma and neurodegenerative diseases can damage the peripheral nervous system and cause functional deficits. Unlike in the central nervous system, damaged axons in peripheral nerves can be induced to regenerate in response to intrinsic cues after reprogramming or in a growth-promoting microenvironment created by Schwann cells. However, axon regeneration and repair do not automatically result in the restoration of function, which is the ultimate therapeutic goal but also a major clinical challenge. Transforming growth factor (TGF) is a multifunctional cytokine that regulates various biological processes including tissue repair, embryo development, and cell growth and differentiation. There is accumulating evidence that TGF-β family proteins participate in peripheral nerve repair through various factors and signaling pathways by regulating the growth and transformation of Schwann cells; recruiting specific immune cells; controlling the permeability of the blood-nerve barrier, thereby stimulating axon growth; and inhibiting remyelination of regenerated axons. TGF-β has been applied to the treatment of peripheral nerve injury in animal models. In this context, we review the functions of TGF-β in peripheral nerve regeneration and potential clinical applications.
    Related Articles | Metrics
    Dynamic transcriptional programs define distinct mammalian cortical lineages
    Tanzila Mukhtar, Verdon Taylor
    2024, 19 (2):  387-389.  doi: 10.4103/1673-5374.377589
    Abstract ( 124 )   PDF (1082KB) ( 42 )   Save
    The cerebral cortex is composed of billions of neurons and glia that are generated sequentially during corticogenesis. These cells are generated in an organized fashion during development. At early stages of brain development, neural stem cells (NSCs) undergo symmetric divisions to expand their pool. Subsequently, most NSCs begin to undergo asymmetric cell divisions to maintain the NSC pool and generate basal progenitors (BPs) that are committed to neuronal differentiation (Mukhtar and Taylor, 2018). BPs divide once or twice and subsequently differentiate into immature newborn neurons (NBNs), which migrate along radial glial fibers to the pial surface of the developing brain. Upon reaching the brain surface, they begin to differentiate to give rise to the respective cortical layers (Figure 1A). Finally, NSCs switch their fate to generate glial cells. Thus, the three phases of corticogenesis can be defined as NSC expansion, neurogenesis, and gliogenesis, which correspond to the main mode of NSC division and the differentiation fate of their progeny into neurons and glia, respectively (Mukhtar and Taylor, 2018).
    Related Articles | Metrics
    Transmission of amyloid-β pathology in humans: a perspective on clinical evidence
    Celso S. G. Catumbela, Rodrigo Morales
    2024, 19 (2):  390-392.  doi: 10.4103/1673-5374.377610
    Abstract ( 94 )   PDF (521KB) ( 43 )   Save
    Transmission of misfolded amyloid-β (Aβ) aggregates between human subjects: Protein misfolding disorders are a family of diseases characterized by the accumulation of misfolded protein aggregates. These proteinaceous structures, also known as amyloids, are key drivers of fatal neurodegenerative disorders such as prion diseases, Alzheimer’s disease (AD), Parkinson’s disease, and others. The amyloidogenic proteins underlying these neuropathologies vary and include infectious prion protein (PrPSc, prion diseases), Aβ (AD), and α-synuclein protein (Parkinson’s disease). Clinical and experimental studies have established a causal relationship between the physicochemical properties of PrPSc and disease in humans (e.g., Creutzfeldt-Jakob disease [CJD]) as well as various other species (e.g., bovine spongiform encephalopathy in cattle, chronic wasting disease in cervids, and scrapie in sheep and goats). Hence, PrPSc is distinguished as a proteinaceous agent able to satisfy Koch’s postulates and remains the sole hallmark of inter-individual transmissible proteinopathies (e.g., iatrogenic CJD [iCJD]) (Brown et al., 2012). Interestingly, studies have convincingly demonstrated that under experimental settings the aberrant conformation of Aβ exhibits numerous features akin to those of PrPSc: highly-ordered and β-sheet-rich protein aggregates, self-propagating properties, and propensity to accumulate in distinct areas of the brain associated with progressive neurodegeneration and cognitive decline, among others (Walker et al., 2016). In turn, reinvigorating efforts have been made to determine whether human-to-human transmission of Aβ aggregates is feasible. Comprehensive reviews by us and others have detailed the results of these studies; wherein reports indicate that inter-human transmission of Aβ-amyloids can occur through medical procedures such as growth hormone treatment and dura mater transplant, albeit rarely, and results in a notably different neuropathology compared to that of AD (Gomez-Gutierrez and Morales, 2020; Lauwers et al., 2020). Following, we address these observations. 
    Related Articles | Metrics
    Preventing brain aging by the artificial enforcement of the unfolded protein response: future directions
    Felipe Cabral-Miranda, Claudio Hetz
    2024, 19 (2):  393-394.  doi: 10.4103/1673-5374.377608
    Abstract ( 116 )   PDF (673KB) ( 68 )   Save
    As the life expectancy of the world’s population increases, age-related diseases are emerging as one of the greatest problems facing modern society. The onset of dementia and neurodegenerative diseases is strictly dependent on aging as a major risk factor and has a profound impact on various aspects of the lives of individuals and their families. The field of aging has defined a number of interrelated pathways and cellular processes, commonly referred to as the “hallmarks of aging,” some of which have emerged as causal factors for age-related changes in brain function (López-Otín et al., 2013). Since most neurodegenerative diseases are characterized by the abnormal deposition of protein aggregates, the deregulation of proteostasis, one of the central pillars of aging, may represent one of the molecular links between normal aging and brain diseases. Indeed, a reduction in the buffering capacity of the proteostasis network is observed during normal aging in various tissues, including the brain, a phenomenon that is exacerbated in neurodegenerative diseases. One of the major nodes of the proteostasis network affected during aging in different species (humans, mice, flies, worms, and yeast) involves the function of the endoplasmic reticulum (ER) and the unfolded protein response (UPR), a signaling pathway that is activated following ER stress (Taylor and Hetz, 2020).
    Related Articles | Metrics
    Astrocyte syncytium: from neonatal genesis to aging degeneration
    Min Zhou, Shiying Zhong, Alexei Verkhratsky
    2024, 19 (2):  395-396.  doi: 10.4103/1673-5374.379047
    Abstract ( 142 )   PDF (596KB) ( 63 )   Save
    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). The neuronal doctrine eventually was victorious and dominated 20th-century neuroscience and neurology. As frequently happens in science, the views of both Cajal and Golgi were correct, and as we know now the central nervous system (CNS) comprises highly coordinated networks of synaptically connected neurons and gap junction-connected neuroglia, the latter being the syncytial or reticular portion of the nervous tissue (Kiyoshi and Zhou, 2019).     
    Related Articles | Metrics
    Lin28 as a therapeutic target for central nervous system regeneration and repair
    Shuo Wang, Shuxin Li
    2024, 19 (2):  397-398.  doi: 10.4103/1673-5374.375322
    Abstract ( 116 )   PDF (610KB) ( 41 )   Save
    Axon disconnection in the central nervous system (CNS) usually causes signal transduction failure and severe functional deficits in patients with neurological disorders. Currently, there is no cure for patients with CNS axon injury and they usually suffer from life-long neurological defects (e.g., paralysis, loss of sensory function, and autonomic dysfunction) and life-threatening complications (e.g., autonomic dysreflexia). In contrast to sufficient regeneration of severed peripheral axons, CNS neurons generally fail to regrow their axons after axotomy. The nonpermissive extrinsic environment and reduced intrinsic regenerative capacity mostly contribute to the regeneration failure of CNS axons. Reactive glial scar tissue around the lesion may have beneficial effects by preventing the primary injury from spreading to adjacent regions at the acute stage, but it eventually hinders axon regrowth by producing physical scar barriers and inhibitory molecules, especially upregulation of chondroitin sulfate proteoglycans around the lesion (Tran et al., 2018). Myelin-associated inhibitors generated by oligodendrocytes, including Nogo, myelin associated glycoprotein, and oligodendrocyte-myelin glycoprotein, partly contribute to the failure of CNS axon regeneration. In the past decades, numerous neuroscientists have focused on identifying novel genes and highly effective strategies to boost the intrinsic growth capacity of mature neurons. A great number of signaling pathways (e.g., phosphatase and tensin homolog (PTEN)/phosphoinositide 3-kinases (PI3K)/protein kinase B (Akt) and Janus kinase/signal transducer and activator of transcription) and transcriptional factors (e.g., Krüppel-like factors, MYC proto-oncogene, and SRY-box transcription factor 11) can regulate the regrowth of injured CNS neurons (Williams et al., 2020). Targeting certain genes, such as PTEN suppression, could induce substantial regrowth of injured CNS neurons, but none of these gene targets have been translated to clinical trials for human treatments. It thus is necessary to identify better targets that may impact multiple pathways for cell growth and provide a more effective approach for CNS regeneration. Recently, the RNA-binding protein Lin28 has become an attractive molecular target for promoting the dramatic regeneration of lesioned CNS neurons (Wang et al., 2018; Nathan et al., 2020), indicating the therapeutic potential of targeting Lin28 and its associated genes for neurological disorders.
    Related Articles | Metrics
    The impact of maternal immune activation on the morphology and electrophysiological properties of postnatally-born neurons in the offspring
    Emilio J. Galván, Angelica Zepeda
    2024, 19 (2):  399-400.  doi: 10.4103/1673-5374.379043
    Abstract ( 123 )   PDF (543KB) ( 42 )   Save

    Pregnancy comes with a combination of physical changes and physiological immunosuppression that increases the susceptibility of women to pathogens and in turn, rises the prevalence of infectious diseases. During this period, the fetal brain is particularly sensitive to internal and external signals that define and guide its development. However, immunosuppression during pregnancy also represents a vulnerable stage in which the combination of molecular signals expressed at specific stages of fetal maturation can result in deficient brain development, a phenomenon poorly understood despite being connected with the risk of developing psychiatric disorders (Knuesel et al., 2014). Strikingly, a potentially harmful signal associated with abnormal brain development in the offspring is the maternal production of cytokines to counteract infectious diseases. Studies have documented that maternal cytokines can cross the placental barrier and influence fetal brain development. This physiological response, also called maternal immune activation (MIA), represents a risk factor for long-lasting alterations in brain development, neuronal activity, and behavioral deficits (for a comprehensive review, see (Estes and McAllister, 2016)). Maternal synthesis and release of pro-inflammatory cytokines, including interleukin 1β, interleukin 6, tumor necrosis factor α, and several interferons, such as interferon-α, in response to environmental insults such as viral or bacterial infections, are associated with dysregulated neuronal physiology and behavioral abnormalities in the offspring. In fact, several psychiatric disorders, among them autism spectrum disorder and schizophrenia, have been postulated to have at least an intrauterine or early-life component associated with viral infections (Atladóttir et al., 2010) and MIA (Vlasova et al., 2021).

    Related Articles | Metrics
    Learning to become addicted, one synapse at a time
    Alessio Attardo, Sidney B. Cambridge
    2024, 19 (2):  401-402.  doi: 10.4103/1673-5374.379046
    Abstract ( 106 )   PDF (296KB) ( 30 )   Save
    Addiction has been extensively studied on many levels: from the molecular level, with various “omics” approaches (Natividad et al., 2018; Grecco et al., 2021), to the clinical level, with psychotherapy and MRI imaging (Ceceli et al., 2022). These approaches have identified brain regions central to addictive processes and reward behavior such as the nucleus accumbens (NA) and the ventral tegmental area. Particularly, the NA exhibits significant volume changes as a consequence of chronic alcohol, heroin, or cigarette abuse as measured by voxel-based morphometry with magnetic resonance imaging in human patients. However, the underlying cellular basis for such large-scale changes is not well understood. Studies in animal models suggest that cellular correlates of volume changes are dependent on alterations in spine/synapse densities and synapse volumes, rather than cell numbers (Keifer et al., 2015). In the NA, substantial spine loss on medium spiny neurons occurs upon withdrawal from various substances of abuse, including alcohol and cocaine (Spiga et al., 2014). Loss of spines is also likely accompanied by a loss of presynaptic boutons; additionally, regional alterations in dendritic arborization could also play a substantial role in the volume changes. While some of these changes may arise as secondary downstream effects due to toxicity after extended substance abuse, morphological changes are beginning to emerge as an important mediator of the effects of substances of abuse on the brain (Russo et al., 2010). Recently, Knabbe et al. (2022) found increased spine turnover and bouton loss in neocortical neurons of somatosensory and motor areas in live mice following a single ethanol administration. This study thus showed that drug-induced morphological changes can occur in brain areas not directly associated with drug-related behavior. If and how such observed morphological changes are critical to the development of addiction is not clear. In the following, we discuss how morphological plasticity processes akin to learning could lead to addiction.
    Related Articles | Metrics
    Stress granules: friend or foe in neurodegenerative disorders?
    Shanshan Xu, Nico P. Dantuma
    2024, 19 (2):  403-404.  doi: 10.4103/1673-5374.379044
    Abstract ( 123 )   PDF (523KB) ( 33 )   Save

    Neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis, despite the diversity in clinical symptoms, share a striking feature at the cellular level: the accumulation of insoluble aggregates of misfolded proteins that are sequestered in intraneuronal inclusion bodies. Besides mutations in disease-associated proteins that render them aggregation-prone, the decline of protein homeostasis (i.e. proteostasis) with aging is also believed to be a contributing factor to the accumulation of protein aggregates. As terminally misfolded proteins are intrinsically toxic, cells have developed mechanisms to minimize potential negative effects of protein aggregates on cell viability. Two main strategies that are at the cell’s disposal are either to eliminate terminally misfolded proteins by protein degradation or to spatially separate them from critical processes by allocating them to destinated intracellular locations through protein sequestration. While it is well established that conditions that cause proteotoxic stress activate mechanisms that regulate degradation and sequestration of misfolded proteins, it is less clear to what extent these two processes are intertwined. Protein sequestration seems to be less of a direct solution to the problem at hand than protein degradation as sequestration merely postpones the point at which the misfolded proteins must be dealt with or, alternatively, the point at which they will cause toxicity. Chemical inhibition of protein degradation results in the formation of inclusion bodies, suggesting that sequestration is a second line of defense that only comes in play under conditions where intracellular protein degradation fails to timely eliminate misfolded proteins. However, could it be that protein sequestration is not just a backup mechanism but also a first responder during proteotoxic stress? Our recent study suggests this to be the case and supports a model where protein sequestration occurs before the degradation machinery is overloaded, thereby preserving a level of protein degradation that is required to rapidly restore proteostasis (Xu et al., 2023). Interestingly, transient sequestration of misfolded proteins at stress granules turned out to be of particular importance, suggesting an additional role for these subcellular, stress-induced structures, next to their well-established connection to the regulation of protein synthesis (Sohnel and Brandt, 2023).  

    Related Articles | Metrics
    Mitochondrial DNA methylation and mitochondria-related epigenetics in neurodegeneration
    Fabio Coppedè
    2024, 19 (2):  405-406.  doi: 10.4103/1673-5374.379045
    Abstract ( 148 )   PDF (449KB) ( 85 )   Save
    Mitochondria are cytoplasmic organelles referred to as the powerhouse of the cell because they are primarily involved in oxidative phosphorylation and energy production. They are particularly abundant in tissues with high energy demands, including muscle, liver, and brain, and mitochondrial dysfunction, oxidative mitochondrial DNA (mtDNA) damage, and impaired mitochondrial dynamics have often been associated with neurodegeneration. The mtDNA is a circular, double-stranded molecule present in two to ten copies per mitochondrion and encodes 13 subunits of the mitochondrial respiratory chain as well as 22 transfer RNAs and two ribosomal RNAs. The existence of mitochondrial epigenetics, and in particular mtDNA methylation, has been largely debated, but a growing body of literature suggests that impaired mtDNA methylation may be involved in neurodegeneration (Coppedè and Stoccoro, 2019). Furthermore, there is increasing evidence for bidirectional crosstalk between the nuclear and mitochondrial genomes to allow coordinated gene expression in response to different cellular stressors. This crosstalk is mainly mediated by epigenetic mechanisms, but is unfortunately still poorly understood in neurodegenerative diseases (Coppedè, 2021). In this perspective, after a brief description of the available literature on impaired mtDNA methylation in neurodegenerative diseases, the author discusses the potential factors contributing to these alterations and their crosstalk with nuclear epigenetics.
    Related Articles | Metrics
    Treadmill training in Parkinson’s disease: possible role of prefrontal modifications in the improved cortical-subcortical network function
    Hao Ding, Amgad Droby, Abdul Rauf Anwar, Jeffrey M. Hausdorff, Bahman Nasseroleslami, Anat Mirelman, Inbal Maidan, Muthuraman Muthuraman
    2024, 19 (2):  407-408.  doi: 10.4103/1673-5374.377607
    Abstract ( 142 )   PDF (506KB) ( 74 )   Save
    Parkinson’s disease (PD) is a complex neurodegenerative disorder characterized by a range of motor symptoms such as bradykinesia, resting tremor, rigidity, and postural instability, as well as non-motor symptoms, such as depression, anxiety, sleep disturbances, and fatigue (Bloem et al., 2021). The underlying pathology involves a progressive loss of dopamine neurons within the substantia nigra, which results in an imbalance between the direct and indirect pathways of the basal ganglia that regulate motor control (Bloem et al., 2021). In addition to pharmacological treatments such as dopamine replacement therapy, non-pharmacological interventions have been investigated in alleviating gait and motor abnormalities in individuals with PD. The use of behavioral interventions in conjunction with pharmacological therapies may offer a more comprehensive approach to managing the motor symptoms of PD. In recent years, neuroimaging techniques have been utilized to explore neural fingerprints of various behavioral interventions (Mak and Wong-Yu, 2019). These techniques have helped elucidate the complex interplay between brain structure and function in PD, offering valuable comprehension of how behavioral approaches could potentially alleviate the motor symptoms of this debilitating disease.
    Related Articles | Metrics
    Activation of endogenous neurogenesis and angiogenesis by basic fibroblast growth factor-chitosan gel in an adult rat model of ischemic stroke
    Hongmei Duan, Shulun Li, Peng Hao, Fei Hao, Wen Zhao, Yudan Gao, Hui Qiao, Yiming Gu, Yang Lv, Xinjie Bao, Kin Chiu, Kwok-Fai So, Zhaoyang Yang, Xiaoguang Li
    2024, 19 (2):  409-415.  doi: 10.4103/1673-5374.375344
    Abstract ( 204 )   PDF (3881KB) ( 54 )   Save
    Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation, differentiation, migration, and survival, as well as angiogenesis, in the context of brain injury. However, whether bioactive materials can repair the damage caused by ischemic stroke by activating endogenous neurogenesis and angiogenesis is still unknown. In this study, we applied chitosan gel loaded with basic fibroblast growth factor to the stroke cavity 7 days after ischemic stroke in rats. The gel slowly released basic fibroblast growth factor, which improved the local microenvironment, activated endogenous neural stem/progenitor cells, and recruited these cells to migrate toward the penumbra and stroke cavity and subsequently differentiate into neurons, while enhancing angiogenesis in the penumbra and stroke cavity and ultimately leading to partial functional recovery. This study revealed the mechanism by which bioactive materials repair ischemic strokes, thus providing a new strategy for the clinical application of bioactive materials in the treatment of ischemic stroke.
    Related Articles | Metrics
    Ethanol changes Nestin-promoter induced neural stem cells to disturb newborn dendritic spine remodeling in the hippocampus of mice
    Guixiang Wang, Wenjia Wang, Ye Zhang, Xiaoying Gou, Qingqing Zhang, Yanmiao Huang, Kuo Zhang, Haotian Zhang, Jingyu Yang, Yuting Li
    2024, 19 (2):  416-424.  doi: 10.4103/1673-5374.379051
    Abstract ( 144 )   PDF (4452KB) ( 156 )   Save

    Adolescent binge drinking leads to long-lasting disorders of the adult central nervous system, particularly aberrant hippocampal neurogenesis. In this study, we applied in vivo fluorescent tracing using NestinCreERT2::Rosa26-tdTomato mice and analyzed the endogenous neurogenesis lineage progression of neural stem cells (NSCs) and dendritic spine formation of newborn neurons in the subgranular zone of the dentate gyrus. We found abnormal orientation of tamoxifen-induced tdTomato+ (tdTom+) NSCs in adult mice 2 months after treatment with EtOH (5.0 g/kg, i.p.) for 7 consecutive days. EtOH markedly inhibited tdTom+ NSCs activation and hippocampal neurogenesis in mouse dentate gyrus from adolescence to adulthood. EtOH (100 mM) also significantly inhibited the proliferation to 39.2% and differentiation of primary NSCs in vitro. Adult mice exposed to EtOH also exhibited marked inhibitions in dendritic spine growth and newborn neuron maturation in the dentate gyrus, which was partially reversed by voluntary running or inhibition of the mammalian target of rapamycin-enhancer of zeste homolog 2 pathway. In vivo tracing revealed that EtOH induced abnormal orientation of tdTom+ NSCs and spatial misposition defects of newborn neurons, thus causing the disturbance of hippocampal neurogenesis and dendritic spine remodeling in mice. 

    Related Articles | Metrics
    Regulation of specific abnormal calcium signals in the hippocampal CA1 and primary cortex M1 alleviates the progression of temporal lobe epilepsy
    Feng Chen, Xi Dong, Zhenhuan Wang, Tongrui Wu, Liangpeng Wei, Yuanyuan Li, Kai Zhang, Zengguang Ma, Chao Tian, Jing Li, Jingyu Zhao, Wei Zhang, Aili Liu, Hui Shen
    2024, 19 (2):  425-433.  doi: 10.4103/1673-5374.379048
    Abstract ( 162 )   PDF (2875KB) ( 142 )   Save
    Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory, resistant to antiepileptic drugs, and has a high recurrence rate. The pathogenesis of temporal lobe epilepsy is complex and is not fully understood. Intracellular calcium dynamics have been implicated in temporal lobe epilepsy. However, the effect of fluctuating calcium activity in CA1 pyramidal neurons on temporal lobe epilepsy is unknown, and no longitudinal studies have investigated calcium activity in pyramidal neurons in the hippocampal CA1 and primary motor cortex M1 of freely moving mice. In this study, we used a multi-channel fiber photometry system to continuously record calcium signals in CA1 and M1 during the temporal lobe epilepsy process. We found that calcium signals varied according to the grade of temporal lobe epilepsy episodes. In particular, cortical spreading depression, which has recently been frequently used to represent the continuously and substantially increased calcium signals, was found to correspond to complex and severe behavioral characteristics of temporal lobe epilepsy ranging from grade II to grade V. However, vigorous calcium oscillations and highly synchronized calcium signals in CA1 and M1 were strongly related to convulsive motor seizures. Chemogenetic inhibition of pyramidal neurons in CA1 significantly attenuated the amplitudes of the calcium signals corresponding to grade I episodes. In addition, the latency of cortical spreading depression was prolonged, and the above-mentioned abnormal calcium signals in CA1 and M1 were also significantly reduced. Intriguingly, it was possible to rescue the altered intracellular calcium dynamics. Via simultaneous analysis of calcium signals and epileptic behaviors, we found that the progression of temporal lobe epilepsy was alleviated when specific calcium signals were reduced, and that the end-point behaviors of temporal lobe epilepsy were improved. Our results indicate that the calcium dynamic between CA1 and M1 may reflect specific epileptic behaviors corresponding to different grades. Furthermore, the selective regulation of abnormal calcium signals in CA1 pyramidal neurons appears to effectively alleviate temporal lobe epilepsy, thereby providing a potential molecular mechanism for a new temporal lobe epilepsy diagnosis and treatment strategy.
    Related Articles | Metrics
    Argatroban promotes recovery of spinal cord injury by inhibiting the PAR1/JAK2/STAT3 signaling pathway
    Chenxi Zhao, Tiangang Zhou, Ming Li, Jie Liu, Xiaoqing Zhao, Yilin Pang, Xinjie Liu, Jiawei Zhang, Lei Ma, Wenxiang Li, Xue Yao, Shiqing Feng
    2024, 19 (2):  434-439.  doi: 10.4103/1673-5374.375345
    Abstract ( 301 )   PDF (1952KB) ( 327 )   Save
    Argatroban is a synthetic thrombin inhibitor approved by U.S. Food and Drug Administration for the treatment of thrombosis. However, whether it plays a role in the repair of spinal cord injury is unknown. In this study, we established a rat model of T10 moderate spinal cord injury using an NYU Impactor Moder III and performed intraperitoneal injection of argatroban for 3 consecutive days. Our results showed that argatroban effectively promoted neurological function recovery after spinal cord injury and decreased thrombin expression and activity in the local injured spinal cord. RNA sequencing transcriptomic analysis revealed that the differentially expressed genes in the argatroban-treated group were enriched in the JAK2/STAT3 pathway, which is involved in astrogliosis and glial scar formation. Western blotting and immunofluorescence results showed that argatroban downregulated the expression of the thrombin receptor PAR1 in the injured spinal cord and the JAK2/STAT3 signal pathway. Argatroban also inhibited the activation and proliferation of astrocytes and reduced glial scar formation in the spinal cord. Taken together, these findings suggest that argatroban may inhibit astrogliosis by inhibiting the thrombin-mediated PAR1/JAK2/STAT3 signal pathway, thereby promoting the recovery of neurological function after spinal cord injury.
    Related Articles | Metrics
    Transplantation of fibrin-thrombin encapsulated human induced neural stem cells promotes functional recovery of spinal cord injury rats through modulation of the microenvironment
    Sumei Liu, Baoguo Liu, Qian Li, Tianqi Zheng, Bochao Liu, Mo Li, Zhiguo Chen
    2024, 19 (2):  440-446.  doi: 10.4103/1673-5374.379049
    Abstract ( 132 )   PDF (2543KB) ( 66 )   Save
    Recent studies have mostly focused on engraftment of cells at the lesioned spinal cord, with the expectation that differentiated neurons facilitate recovery. Only a few studies have attempted to use transplanted cells and/or biomaterials as major modulators of the spinal cord injury microenvironment. Here, we aimed to investigate the role of microenvironment modulation by cell graft on functional recovery after spinal cord injury. Induced neural stem cells reprogrammed from human peripheral blood mononuclear cells, and/or thrombin plus fibrinogen, were transplanted into the lesion site of an immunosuppressed rat spinal cord injury model. Basso, Beattie and Bresnahan score, electrophysiological function, and immunofluorescence/histological analyses showed that transplantation facilitates motor and electrophysiological function, reduces lesion volume, and promotes axonal neurofilament expression at the lesion core. Examination of the graft and niche components revealed that although the graft only survived for a relatively short period (up to 15 days), it still had a crucial impact on the microenvironment. Altogether, induced neural stem cells and human fibrin reduced the number of infiltrated immune cells, biased microglia towards a regenerative M2 phenotype, and changed the cytokine expression profile at the lesion site. Graft-induced changes of the microenvironment during the acute and subacute stages might have disrupted the inflammatory cascade chain reactions, which may have exerted a long-term impact on the functional recovery of spinal cord injury rats.
    Related Articles | Metrics
    BMPRII+ neural precursor cells isolated and characterized from organotypic neurospheres: an in vitro model of human fetal spinal cord development
    Michael W. Weible II, Michael D. Lovelace, Hamish D. Mundell, Tsz Wai Rosita Pang, Tailoi Chan-Ling
    2024, 19 (2):  447-457.  doi: 10.4103/1673-5374.373669
    Abstract ( 93 )   PDF (7646KB) ( 15 )   Save
    Roof plate secretion of bone morphogenetic proteins (BMPs) directs the cellular fate of sensory neurons during spinal cord development, including the formation of the ascending sensory columns, though their biology is not well understood. Type-II BMP receptor (BMPRII), the cognate receptor, is expressed by neural precursor cells during embryogenesis; however, an in vitro method of enriching BMPRII+ human neural precursor cells (hNPCs) from the fetal spinal cord is absent. Immunofluorescence was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRII and leukemia inhibitory factor (LIF). Regions of highest BMPRII+ immunofluorescence localized to sensory columns. Parenchymal and meningeal-associated BMPRII+ vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers, CD34/CD39. LIF immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons, mirroring the expression of LIF receptor/CD118. A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages, while synergistically increasing the proportion of neurospheres with a stratified, cytoarchitecture. These neurospheres were characterized by BMPRII+/MAP2ab+/–/βIII-tubulin+/nestin–/vimentin–/GFAP–/NeuN– surface hNPCs surrounding a heterogeneous core of βIII-tubulin+/nestin+/vimentin+/GFAP+/MAP2ab–/NeuN– multipotent precursors. Dissociated cultures from tripotential neurospheres contained neuronal (βIII-tubulin+), astrocytic (GFAP+), and oligodendrocytic (O4+) lineage cells. Fluorescence-activated cell sorting-sorted BMPRII+ hNPCs were MAP2ab+/–/βIII-tubulin+/GFAP–/O4– in culture. This is the first isolation of BMPRII+ hNPCs identified and characterized in human fetal spinal cords. Our data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres, characterized by surface BMPRII+ hNPCs. Our study has provided a new methodology for an in vitro model capable of amplifying human fetal spinal cord cell numbers for > 10 passages. Investigations of the role BMPRII plays in spinal cord development have primarily relied upon mouse and rat models, with interpolations to human development being derived through inference. Because of significant species differences between murine biology and human, including anatomical dissimilarities in central nervous system (CNS) structure, the findings made in murine models cannot be presumed to apply to human spinal cord development. For these reasons, our human in vitro model offers a novel tool to better understand neurodevelopmental pathways, including BMP signaling, as well as spinal cord injury research and testing drug therapies.
    Related Articles | Metrics
    One-step cell biomanufacturing platform: porous gelatin microcarrier beads promote human embryonic stem cell-derived midbrain dopaminergic progenitor cell differentiation in vitro and survival after transplantation in vivo
    Lin Feng, Da Li, Yao Tian, Chengshun Zhao, Yun Sun, Xiaolong Kou, Jun Wu, Liu Wang, Qi Gu, Wei Li, Jie Hao, Baoyang Hu, Yukai Wang
    2024, 19 (2):  458-464.  doi: 10.4103/1673-5374.377412
    Abstract ( 154 )   PDF (3181KB) ( 104 )   Save
    Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s disease. Transplantation of midbrain dopaminergic progenitor cells is a promising treatment for Parkinson’s disease. However, transplanted cells can be injured by mechanical damage during handling and by changes in the transplantation niche. Here, we developed a one-step biomanufacturing platform that uses small-aperture gelatin microcarriers to produce beads carrying midbrain dopaminergic progenitor cells. These beads allow midbrain dopaminergic progenitor cell differentiation and cryopreservation without digestion, effectively maintaining axonal integrity in vitro. Importantly, midbrain dopaminergic progenitor cell bead grafts showed increased survival and only mild immunoreactivity in vivo compared with suspended midbrain dopaminergic progenitor cell grafts. Overall, our findings show that these midbrain dopaminergic progenitor cell beads enhance the effectiveness of neuronal cell transplantation.
    Related Articles | Metrics