Autophagy in Oligodendrocyte Lineage Cells Controls Oligodendrocyte Numbers and Myelin Integrity in an Age-dependent Manner.

Oligodendrocyte lineage cells, including oligodendrocyte precursor cells (OPCs) and oligodendrocytes (OLs), are essential in establishing and maintaining brain circuits. Autophagy is a conserved process that keeps the quality of organelles and proteostasis. The role of autophagy in oligodendrocyte lineage cells remains unclear. The present study shows that autophagy is required to maintain the number of OPCs/OLs and myelin integrity during brain aging. Inactivation of autophagy in oligodendrocyte lineage cells increases the number of OPCs/OLs in the developing brain while exaggerating the loss of OPCs/OLs with brain aging. Inactivation of autophagy in oligodendrocyte lineage cells impairs the turnover of myelin basic protein (MBP). It causes MBP to accumulate in the cytoplasm as multimeric aggregates and fails to be incorporated into integral myelin, which is associated with attenuated endocytic recycling. Inactivation of autophagy in oligodendrocyte lineage cells impairs myelin integrity and causes demyelination. Thus, this study shows autophagy is required to maintain myelin quality during aging by controlling the turnover of myelin components.

GPR50 regulates neuronal development as a mitophagy receptor.

Neurons rely heavily on high mitochondrial metabolism to provide sufficient energy for proper development. However, it remains unclear how neurons maintain high oxidative phosphorylation (OXPHOS) during development. Mitophagy plays a pivotal role in maintaining mitochondrial quality and quantity. We herein describe that G protein-coupled receptor 50 (GPR50) is a novel mitophagy receptor, which harbors the LC3-interacting region (LIR) and is required in mitophagy under stress conditions. Although it does not localize in mitochondria under normal culturing conditions, GPR50 is recruited to the depolarized mitochondrial membrane upon mitophagy stress, which marks the mitochondrial portion and recruits the assembling autophagosomes, eventually facilitating the mitochondrial fragments to be engulfed by the autophagosomes. Mutations Δ502-505 and T532A attenuate GPR50-mediated mitophagy by disrupting the binding of GPR50 to LC3 and the mitochondrial recruitment of GPR50. Deficiency of GPR50 causes the accumulation of damaged mitochondria and disrupts OXPHOS, resulting in insufficient ATP production and excessive ROS generation, eventually impairing neuronal development. GPR50-deficient mice exhibit impaired social recognition, which is rescued by prenatal treatment with mitoQ, a mitochondrially antioxidant. The present study identifies GPR50 as a novel mitophagy receptor that is required to maintain mitochondrial OXPHOS in developing neurons.

Glial growth factor 2 treatment alleviates ischemia and reperfusion-damaged integrity of the blood-brain barrier through decreasing Mfsd2a/caveolin-1-mediated transcellular and Pdlim5/YAP/TAZ-mediated paracellular permeability.

The impairment of blood-brain barrier (BBB) integrity is the pathological basis of hemorrhage transformation and vasogenic edema following thrombolysis and endovascular therapy. There is no approved drug in the clinic to reduce BBB damage after acute ischemic stroke (AIS). Glial growth factor 2 (GGF2), a recombinant version of neuregulin-1ß that can stimulates glial cell proliferation and differentiation, has been shown to alleviate free radical release from activated microglial cells. We previously found that activated microglia and proinflammatory factors could disrupt BBB after AIS. In this study we investigated the effects of GGF2 on AIS-induced BBB damage as well as the underlying mechanisms. Mouse middle cerebral artery occlusion model was established: mice received a 90-min ischemia and 22.5 h reperfusion (I/R), and were treated with GGF2 (2.5, 12.5, 50 ng/kg, i.v.) before the reperfusion. We showed that GGF2 treatment dose-dependently decreased I/R-induced BBB damage detected by Evans blue (EB) and immunoglobulin G (IgG) leakage, and tight junction protein occludin degradation. In addition, we found that GGF2 dose-dependently reversed AIS-induced upregulation of vesicular transcytosis increase, caveolin-1 (Cav-1) as well as downregulation of major facilitator superfamily domain containing 2a (Mfsd2a). Moreover, GGF2 decreased I/R-induced upregulation of PDZ and LIM domain protein 5 (Pdlim5), an adaptor protein that played an important role in BBB damage after AIS. In addition, GGF2 significantly alleviated I/R-induced reduction of YAP and TAZ, microglial cell activation and upregulation of inflammatory factors. Together, these results demonstrate that GGF2 treatment alleviates the I/R-compromised integrity of BBB by inhibiting Mfsd2a/Cav-1-mediated transcellular permeability and Pdlim5/YAP/TAZ-mediated paracellular permeability.

Analysis of the influences of social isolation on cognition and the therapeutic potential of deep brain stimulation in a mouse model.

Background: Social interaction is a fundamental human need. Social isolation (SI) can have negative effects on both emotional and cognitive function. However, it is currently unclear how age and the duration of SI affect emotion and recognition function. In addition, there is no specific treatment for the effects of SI. Methods: The adolescence or adult mice were individually housed in cages for 1, 6 or 12 months and for 2 months to estabolish SI mouse model. We investigated the effects of SI on behavior in mice at different ages and under distinct durations of SI, and we explored the possible underlying mechanisms. Then we performed deep brain stimulation (DBS) to evaluate its influences on SI induced behavioral abnormalities. Results: We found that social recognition was affected in the short term, while social preference was damaged by extremely long periods of SI. In addition to affecting social memory, SI also affects emotion, short-term spatial ability and learning willingness in mice. Myelin was decreased significantly in the medial prefrontal cortex (mPFC) and dorsal hippocampus of socially isolated mice. Cellular activity in response to social stimulation in both areas was impaired by social isolation. By stimulating the mPFC using DBS, we found that DBS alleviated cellular activation disorders in the mPFC after long-term SI and improved social preference in mice. Conclusion: Our results suggest that the therapeutic potential of stimulating the mPFC with DBS in individuals with social preference deficits caused by long-term social isolation, as well as the effects of DBS on the cellular activity and density of OPCs.

Transcranial low-intensity ultrasound stimulation for treating central nervous system disorders: A promising therapeutic application.

Transcranial ultrasound stimulation is a neurostimulation technique that has gradually attracted the attention of researchers, especially as a potential therapy for neurological disorders, because of its high spatial resolution, its good penetration depth, and its non-invasiveness. Ultrasound can be categorized as high-intensity and low-intensity based on the intensity of its acoustic wave. High-intensity ultrasound can be used for thermal ablation by taking advantage of its high-energy characteristics. Low-intensity ultrasound, which produces low energy, can be used as a means to regulate the nervous system. The present review describes the current status of research on low-intensity transcranial ultrasound stimulation (LITUS) in the treatment of neurological disorders, such as epilepsy, essential tremor, depression, Parkinson's disease (PD), and Alzheimer's disease (AD). This review summarizes preclinical and clinical studies using LITUS to treat the aforementioned neurological disorders and discusses their underlying mechanisms.

Mixed cellulose ester membrane as an ion redistributor to stabilize zinc anode in aqueous zinc ion batteries.

Aqueous zinc-ion batteries (AZBs) with high energy density, low cost and environmental characteristics, have become the promising device for energy storage. However, uncontrolled zinc dendrite growth remains an impediment to the popularization of AZBs. The unrestricted two-dimensional (2D) ions diffusion is the main cause of the above defect. In this work, mixed cellulose ester (MCE) membrane is proposed as the separator. A dense homogeneous pore structure can achieve a physical shunting effect on ion diffusion, which can control and homogenize the ion motion. Further, the mechanism of this physical pore effect is confirmed by comparing the behavior of Zn deposition in MCE systems with different pore sizes but the same composition. As conjectured, a membrane with a smaller pore size is more favorable. In addition, the MCE contains many polar oxygen-containing functional groups that can facilitate and modulate ion diffusion through coordination. This chemical ion guiding effect, together with the above physical pore effect, gives the separator the ability to suppress dendrite formation. Zn/Zn symmetric cells with this membrane exhibit ultralong cycle life exceeding 1250 h at 0.5 mA cm-2 and 1000 h at 5 mA cm-2. And the Zn//MnO2 battery presents excellent cycle stability for more than 500 cycles with a capacity retention of 90.67%. This work proposes MCE separators and reveals their coordinated regulation of physical and chemical effects on metal-based anodes. This will shed light on the development of high-performance separators and AZBs.

Nicotine pretreatment alleviates MK-801-induced behavioral and cognitive deficits in mice by regulating Pdlim5/CRTC1 in the PFC.

Increasing evidence shows that smoking-obtained nicotine is indicated to improve cognition and mitigate certain symptoms of schizophrenia. In this study, we investigated whether chronic nicotine treatment alleviated MK-801-induced schizophrenia-like symptoms and cognitive impairment in mice. Mice were injected with MK-801 (0.2 mg/kg, i.p.), and the behavioral deficits were assessed using prepulse inhibition (PPI) and T-maze tests. We showed that MK-801 caused cognitive impairment accompanied by increased expression of PDZ and LIM domain 5 (Pdlim5), an adaptor protein that is critically associated with schizophrenia, in the prefrontal cortex (PFC). Pretreatment with nicotine (0.2 mg · kg-1 · d-1, s.c., for 2 weeks) significantly ameliorated MK-801-induced schizophrenia-like symptoms and cognitive impairment by reversing the increased Pdlim5 expression levels in the PFC. In addition, pretreatment with nicotine prevented the MK-801-induced decrease in CREB-regulated transcription coactivator 1 (CRTC1), a coactivator of CREB that plays an important role in cognition. Furthermore, MK-801 neither induced schizophrenia-like behaviors nor decreased CRTC1 levels in the PFC of Pdlim5-/- mice. Overexpression of Pdlim5 in the PFC through intra-PFC infusion of an adreno-associated virus AAV-Pdlim5 induced significant schizophrenia-like symptoms and cognitive impairment. In conclusion, chronic nicotine treatment alleviates schizophrenia-induced memory deficits in mice by regulating Pdlim5 and CRTC1 expression in the PFC.

Engineering the interface of organic/inorganic composite solid-state electrolyte by amino effect for all-solid-state lithium batteries.

Composite solid-state electrolyte (CSSE) with integrated strengths avoids the weaknesses of organic and inorganic electrolytes, and thus become a better choice for all-solid-state lithium battery (ASSLB). However, the poor dispersion of inorganic fillers and the organic/inorganic nature difference leads to their interface incompatibility, which greatly destroys the performance of CSSE and ASSLB. Herein, silane coupling agent (SCA) aminopropyl triethoxysilane (ATS) is introduced to tailor the organic/inorganic interfaces in CSSE by the common chemical bridging effect of SCA and the special amino effect (hydrogen bond and lone pair electron effects). It is found that the hydrogen bond interaction between -NH2 and polyethylene oxide (PEO) enhances their interface interaction. And the lone pair electrons on nitrogen atom allow it to react with solvent acetonitrile and promote the uniform dispersion of ceramic fillers. Moreover, the lone pair electrons can complex with Li+, which promotes the dissociation of Li salts, uniforms Li+ diffusion and inhibits the Li dendrite. Thanks to the above merits, the interface compatibility and stability of organic/inorganic CSSE are much enhanced by innovatively introducing ATS, showing high ionic conductivity and superior mechanical/thermal stability. The ASSLB with this modified CSSE exhibits excellent electrochemical performance with a reversible capacity of 140.9 mAh g-1 and a capacity retention of 94.4% after 280 cycles. These achievements offer a new insight into improving the stability of organic/inorganic CSSE interface and promoting their applicability into ASSLB.

The Stem Cell Potential of O-2A Lineage Astroglia.

Astrocytes are the most common glial type in the central nervous system. They play pivotal roles in neurophysiological and neuropathological processes. Mounting evidence indicates that astrocytes may act as neural stem cells and contribute to adult neurogenesis. In previous reports, freshly isolated O-2A progenitors were shown to revert to neural stem-like cells (NSLCs) when cultured with a serum-containing glial medium or bone morphogenic proteins for 3 days and with basic fibroblast growth factor consecutively. NSLCs possess self-renewal and multipotential capacities that can give rise to neurons and glial cells, which suggests that they have stem cell-like properties. However, the underlying molecular mechanisms and cell fate commitment when exposed to a neural conditioned medium remain obscure. In this study, we demonstrated that NSLCs grown in the serum-containing neurobasal medium can differentiate into induced neural-like cells (iNLCs). It was noteworthy that astroglia mixed in these cells, particularly in iNLCs, were gradually replaced by neural phenotypes during this glia-neuron conversion. Remarkably, these glial cells can maintain high levels of proliferation and self-renewal ability by activating the NF-κB and MAPK signals. Finally, we found that Notch, STAT3, autophagy, bHLH, and Wnt signals appear to be critical modulators of these intricate events. Altogether, these data demonstrate that O-2A lineage astroglia can function as neural stem cells and display neurogenic plasticity. Dissecting the regulatory pathways involved in these processes is essential to the understanding of glial cell fate and its precise functions. This finding may foster a better understanding of astrocytic heterogeneity and lead to innovative ways to readily apply stem-like astroglia cells as candidate cell sources for neural repair.

TRIM32 Deficiency Impairs the Generation of Pyramidal Neurons in Developing Cerebral Cortex.

Excitatory-inhibitory imbalance (E/I) is a fundamental mechanism underlying autism spectrum disorders (ASD). TRIM32 is a risk gene genetically associated with ASD. The absence of TRIM32 causes impaired generation of inhibitory GABAergic interneurons, neural network hyperexcitability, and autism-like behavior in mice, emphasizing the role of TRIM32 in maintaining E/I balance, but despite the description of TRIM32 in regulating proliferation and differentiation of cultured mouse neural progenitor cells (NPCs), the role of TRIM32 in cerebral cortical development, particularly in the production of excitatory pyramidal neurons, remains unknown. The present study observed that TRIM32 deficiency resulted in decreased numbers of distinct layer-specific cortical neurons and decreased radial glial cell (RGC) and intermediate progenitor cell (IPC) pool size. We further demonstrated that TRIM32 deficiency impairs self-renewal of RGCs and IPCs as indicated by decreased proliferation and mitosis. A TRIM32 deficiency also affects or influences the formation of cortical neurons. As a result, TRIM32-deficient mice showed smaller brain size. At the molecular level, RNAseq analysis indicated reduced Notch signalling in TRIM32-deficient mice. Therefore, the present study indicates a role for TRIM32 in pyramidal neuron generation. Impaired generation of excitatory pyramidal neurons may explain the hyperexcitability observed in TRIM32-deficient mice.

Clemastine attenuates AD-like pathology in an AD model mouse via enhancing mTOR-mediated autophagy.

Alzheimer's disease (AD) is a neurodegenerative disorder with limited available drugs for treatment. Enhancing autophagy attenuates AD pathology in various AD model mice. Thus, development of potential drugs which enhance autophagy may bring beneficial effects in AD therapy. In the present study, we show clemastine, a first-generation histamine H1R antagonist and being originally marketed for the treatment of allergic rhinitis, ameliorates AD pathogenesis in APP/PS1 transgenic mice. Chronic treatment with clemastine orally reduced amyloid-ß (Aß) load, neuroinflammation and cognitive deficits of APP/PS1 transgenic mice. Clemastine decreases Aß generation via reducing the levels of BACE1, CTFs of APP. Mechanistically, clemastine enhances autophagy concomitant with a suppression of mTOR signaling. Therefore, we propose that clemastine attenuates AD pathology via enhancing mTOR-mediated autophagy.

Intranasal Transplantation of Human Neural Stem Cells Ameliorates Alzheimer's Disease-Like Pathology in a Mouse Model.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by memory impairments, which has no effective therapy. Stem cell transplantation shows great potential in the therapy of various disease. However, the application of stem cell therapy in neurological disorders, especially the ones with a long-term disease course such as AD, is limited by the delivery approach due to the presence of the brain blood barrier. So far, the most commonly used delivery approach in the therapy of neurological disorders with stem cells in preclinical and clinical studies are intracranial injection and intrathecal injection, both of which are invasive. In the present study, we use repetitive intranasal delivery of human neural stem cells (hNSCs) to the brains of APP/PS1 transgenic mice to investigate the effect of hNSCs on the pathology of AD. The results indicate that the intranasally transplanted hNSCs survive and exhibit extensive migration and higher neuronal differentiation, with a relatively limited glial differentiation. A proportion of intranasally transplanted hNSCs differentiate to cholinergic neurons, which rescue cholinergic dysfunction in APP/PS1 mice. In addition, intranasal transplantation of hNSCs attenuates ß-amyloid accumulation by upregulating the expression of ß-amyloid degrading enzymes, insulin-degrading enzymes, and neprilysin. Moreover, intranasal transplantation of hNSCs ameliorates other AD-like pathology including neuroinflammation, cholinergic dysfunction, and pericytic and synaptic loss, while enhancing adult hippocampal neurogenesis, eventually rescuing the cognitive deficits of APP/PS1 transgenic mice. Thus, our findings highlight that intranasal transplantation of hNSCs benefits cognition through multiple mechanisms, and exhibit the great potential of intranasal administration of stem cells as a non-invasive therapeutic strategy for AD.

Mitigating the Microcracks of High-Ni Oxides by In Situ Formation of Binder between Anisotropic Grains for Lithium-Ion Batteries.

Increasing attention has been paid to layered high-Ni oxides with high capacity as a promising cathode for high-energy lithium-ion batteries. However, the undesirable microcracks in secondary particles usually occur due to the volume changes of anisotropic primary grains during cycles, which lead to the decay of electrochemical performance. Here, for the first time, a functional electrolyte with di-sec-butoxyaluminoxytriethoxysilane additive integrating the functions of silane and aluminate is proposed to in situ form the binder-like filler between anisotropic primary grains for mitigating the microcracks of high-Ni oxides. It is demonstrated that Li-containing aluminosilicate as a glue layer between the gaps of grains and as a coating layer on the surface of the grains is generated, and these features further enhance the interfacial bonding and surface stability of anisotropic primary grains. Consequently, the microcracks along with side reactions and phase transitions of high-Ni oxides are mitigated. As anticipated, the electrochemical performance and thermal stability of high-Ni oxides are improved, and there is also a capacity retention of 75.4% even after 300 cycles and large reversible capacity of ∼160 mA h g-1 at 5 C. The functional electrolyte offers a simple, efficient, and scalable method to promote the electrochemical properties and applicability of high-Ni oxide cathodes in high-energy lithium-ion batteries.

Metalophilic Gel Polymer Electrolyte for in Situ Tailoring Cathode/Electrolyte Interface of High-Nickel Oxide Cathodes in Quasi-Solid-State Li-Ion Batteries.

High-Ni layered oxides are potential cathodes for high energy Li-ion batteries due to their large specific capacity advantage. However, the fast capacity fade by undesirable structural degradation in liquid electrolyte during long-term cycling is a stumbling block for the commercial application of high-Ni oxides. In this work, a functional gel polymer electrolyte, grafted with sodium alginate, is introduced to increase the stability of high-Ni oxide cathodes at the levels of both the particle and electrode. An in situ generated ion-conducting layer appears on the interface through the chemical interaction between transition-metal cations of the cathode and the metalophilic reticulum group in sodium alginate. Such a tailoring layer can not only enhance the interfacial compatibility on the cathode/electrolyte interface, reducing the interfacial resistance, but also inhibit the HF corrosion, suppressing the dissolution of transition-metal cations and harmful gradient distribution of components through the oxide cathode at the electrode level. Meanwhile, detrimental microcracks in oxide microspheres and between primary crystallites are impressively inhibited at the particle level. The high-Ni oxide cathode with the metalophilic gel polymer electrolyte shows excellent cycle stability with large initial capacity of 204.9 mA h g-1 at a 1.0 C rate and high discharge capacity retention within 300 cycles at high temperature.

LiMn0.8Fe0.2PO4/Carbon Nanospheres@Graphene Nanoribbons Prepared by the Biomineralization Process as the Cathode for Lithium-Ion Batteries.

Biomineralization technology is a feasible and promising route to fabricate phosphate cathode materials with hierarchical nanostructure for high-performance lithium-ion batteries (LIBs). In this work, to improve the electrochemical performance of LiMn0.8Fe0.2PO4 (LMFP), hierarchical LMFP/carbon nanospheres are wrapped in situ with N-doped graphene nanoribbons (GNRs) via biomineralization by using yeast cells as the nucleating agent, self-assembly template, and carbon source. Such LMFP nanospheres are assembled by more fine nanocrystals with an average size of 18.3 nm. Moreover, the preferential crystal orientation along the [010] direction and certain antisite lattice defects can be identified in LMFP nanocrystals, which promote rapid diffusion of Li ions and generate more active sites for the electrochemical reaction. Moreover, such N-doped GNR networks, wrapped between LMFP/carbon nanospheres, are beneficial to the fast mobility of electrons and good penetration of the electrolyte. As expected, the as-prepared LMFP/carbon multicomposite presents the outstanding electrochemical performance, including the large initial discharge capacity of 168.8 mA h g-1, good rate capability, and excellent long-term cycling stability over 2000 cycles. Therefore, the biomineralization method is demonstrated here to be effective to manipulate the microstructure of multicomponent phosphate cathode materials based on the requirement of capacity, rate capability, and cycle stability for LIBs.