Identification and cross-validation of autophagy-related genes in cardioembolic stroke.

Objective: Cardioembolic stroke (CE stroke, also known as cardiogenic cerebral embolism, CCE) has the highest recurrence rate and fatality rate among all subtypes of ischemic stroke, the pathogenesis of which was unclear. Autophagy plays an essential role in the development of CE stroke. We aim to identify the potential autophagy-related molecular markers of CE stroke and uncover the potential therapeutic targets through bioinformatics analysis. Methods: The mRNA expression profile dataset GSE58294 was obtained from the GEO database. The potential autophagy-related differentially expressed (DE) genes of CE stroke were screened by R software. Protein-protein interactions (PPIs), correlation analysis, and gene ontology (GO) enrichment analysis were applied to the autophagy-related DE genes. GSE66724, GSE41177, and GSE22255 were introduced for the verification of the autophagy-related DE genes in CE stroke, and the differences in values were re-calculated by Student's t-test. Results: A total of 41 autophagy-related DE genes (37 upregulated genes and four downregulated genes) were identified between 23 cardioembolic stroke patients (≤3 h, prior to treatment) and 23 healthy controls. The KEGG and GO enrichment analysis of autophagy-related DE genes indicated several enriched terms related to autophagy, apoptosis, and ER stress. The PPI results demonstrated the interactions between these autophagy-related genes. Moreover, several hub genes, especially for CE stroke, were identified and re-calculated by Student's t-test. Conclusion: We identified 41 potential autophagy-related genes associated with CE stroke through bioinformatics analysis. SERPINA1, WDFY3, ERN1, RHEB, and BCL2L1 were identified as the most significant DE genes that may affect the development of CE stroke by regulating autophagy. CXCR4 was identified as a hub gene of all types of strokes. ARNT, MAPK1, ATG12, ATG16L2, ATG2B, and BECN1 were identified as particular hub genes for CE stroke. These results may provide insight into the role of autophagy in CE stroke and contribute to the discovery of potential therapeutic targets for CE stroke treatment.

Electroacupuncture regulates microglia polarization via lncRNA-mediated hippo pathway after ischemic stroke.

Microglia polarization and microglia-mediated inflammation play a crucial role in the development of ischaemic brain injury. Electroacupuncture (EA) has the function of anti-inflammatory, which has been thoroughly validated and utilized to treat ischemic brain damage. The fundamental mechanism by which EA alleviates ischemic brain damage by decreasing microglia polarization and microglia-mediated inflammation, however, remains unknown. In the current study, the activation of microglia and inflammatory cytokines was analyzed to confirm the anti-inflammatory function of EA in middle cerebral artery occlusion (MCAO) rats. Whole-transcriptome sequencing was used to examine the differentially expressed lncRNAs in the control, MCAO, and MCAO +EA groups. Our findings demonstrated that EA treatment reduced microglia activation and inflammatory cytokine production. In addition, there are 44 lncRNAs were found significantly different in three groups, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway of the predicted targets of these lncRNAs suggested that the Hippo pathway may contribute to the development of ischaemic brain injury and to the anti-inflammatory function of EA. Moreover, our data showed that lncRNA TCONS_00022826 (Lnc826) was upregulated in MCAO group, whereas blocked by EA treatment. Furthermore, in vitro OGD cell model data showed that Lnc826 promoted M1 polarization of microglia by regulating the Hippo pathway. Our data suggested that regulating microglia polarization via Lnc826-mediated hippo pathway is a possible mechanism of the EA treatment on ischemic brain injury.

Production of 11-Oxo-ß-Amyrin in Saccharomyces cerevisiae at High Efficiency by Fine-Tuning the Expression Ratio of CYP450:CPR.

The production of glycyrrhetinic acid (GA) and 11-oxo-ß-amyrin, the major bioactive components in liquorice, was typically inhibited by P450 oxidation in Saccharomyces cerevisiae. This study focused on optimizing CYP88D6 oxidation by balancing its expression with cytochrome P450 oxidoreductase (CPR) for the efficient production of 11-oxo-ß-amyrin in yeast. Results indicated that a high CPR:CYP88D6 expression ratio could decrease both 11-oxo-ß-amyrin concentration and turnover ratio of ß-amyrin to 11-oxo-ß-amyrin, whereas a high CYP88D6:CPR expression ratio is beneficial for improving the catalytic activity of CYP88D6 and 11-oxo-ß-amyrin production. Under such a scenario, 91.2% of ß-amyrin was converted into 11-oxo-ß-amyrin in the resulting S. cerevisiae Y321, and 11-oxo-ß-amyrin production was further improved to 810.6 mg/L in fed-batch fermentation. Our study provides new insights into the expression of cytochrome P450 and CPR in maximizing the catalytic activity of P450s, which could guide the construction of cell factories in producing natural products.

Catechin, rutin and quercetin in Quercus mongolica Fisch leaves exert inhibitory effects on multiple cancer cells.

We aimed to identify anti-tumor agents in Quercus mongolica Fisch (QMF). Bioactive compounds in QMF leaves, which were extracted using ethanol as a co-solvent. Five point zero six grams of flavonoids were obtained from 100 g of QMF leaves. Catechin (18.4%), rutin (6.3%), ellagic acid (34.9%), quercetin (5.1%) and kaempferol (20.6%) are the main ingredients of the extracts and were further purified by HPLC. CCK-8 cell proliferation assay showed that catechin and ellagic acid exerted strong inhibitory effects on the proliferation of all cancer cells with lower IC50 values against MCF-7 human breast cancer cell lines, SMMC-7721 human hepatocellular carcinoma cells, HeLa human cervical carcinoma cell lines and SKOV3 human ovarian carcinoma cell lines (p < .05). Catechin, rutin and quercetin induced a higher rate of apoptosis and inhibited all cancer cell proliferation by inducing the G0/G1 phase and G2/M phase arrest (p < .05). However, ellagic acid induced tumor cell death, not through apoptosis and there may be other molecular mechanisms. High levels of catechin and ellagic acid in QMF can be developed as potential drugs to treat different types of cancer cells. PRACTICAL APPLICATIONS: Quercus species have been widely studied because of their antioxidant, anti-inflammatory, antimicrobial, and anti-tumor properties. Bioactive compounds in the leaves of Quercus mongolica Fisch have high levels of catechin and ellagic acid, which exert significant inhibitory properties on the proliferation of various types of cancer cells. Therefore, the bioactive compounds may be potential natural drugs in the prevention of cancer development and progression.

Functional analyses of inhibitor of apoptosis protein 1 (IAP1) of Antheraea pernyi multinucleocapsid nucleopolyhedrovirus (AnpeNPV) in viral replication and occlusion body production.

Inhibitor of apoptosis protein 1 (IAP1) of Antheraea pernyi multinucleocapsid nucleopolyhedrovirus (AnpeNPV) belongs to the baculovirus IAP1 type. The function of AnpeNPV-IAP1 in viral replication and occlusion body (OB) production remains unknown. In this study, we demonstrated that AnpeNPV-iap1 is a late gene. AnpeNPV-IAP1 mainly localizes to the nuclear ring zone and exhibits dynamic distribution in the cytoplasm and the virogenic stroma during AnpeNPV infection. AnpeNPV-IAP1 impacted the expression of a variety of viral genes at the very late phase of infection in Tn-Hi5 cells. The deletion of AnpeNPV-iap1 caused decreased expression levels of polyhedrin, morphological changes to OBs and reduced OB production in A. pernyi pupae, along with a lengthening of the lethal time of A. pernyi larvae. These results suggest that AnpeNPV-iap1 is involved in regulating viral gene expression, OB production and morphogenesis in A. pernyi.

Knockdown of zinc finger protein 267 suppresses diffuse large B-cell lymphoma progression, metastasis, and cancer stem cell properties.

Zinc finger protein 267 (ZNF267) is a member of the Kruppel-like transcription factor family, which regulates various biological processes such as cell proliferation and differentiation. However, the biological significance of ZNF267 and its potential role in diffuse large B-cell lymphoma (DLBCL) remain to be documented. Experiments were herein conducted to study the role of ZNF267 in DLBCL. real-time quantitative reverse transcription PCR and Western blotting assays were conducted to detect the expression of ZNF267 in tissues and cells. Tissue microarray and bioinformatics analyses of public data were also done to detect the expression status and clinical significance of ZNF267. Functional cell experiments including CCK8 assay, colony formation assay, 5-ethynyl-2'-deoxyuridine (EDU) assay, terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) assay, transwell assay, and wound healing assay were conducted to study the effects of ZNF267 knockdown and overexpression on cell proliferation and mobility. Xenograft assay was also conducted to confirm the effects of ZNF267 knockdown in vivo. In the present study, we found ZNF267 was significantly upregulated in DLBCL and predicted a poor survival outcome based on the bioinformatics analysis. Functionally, the knockdown of ZNF267 resulted in less cell proliferation and mobility, whereas the overexpression led to enhanced cell proliferation and mobility. Animal experiments also confirmed that ZNF267 silence contributed to less tumor growth and less lung metastasis. Further analysis showed that ZFN267 knockdown resulted in decreased epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) properties. Our results suggest that ZNF267 is an oncogene in DLBCL and its silence could compromise the aggression of DLBCL, which makes ZNF267 a promising therapeutic target.

The lymphatic drainage system of the CNS plays a role in lymphatic drainage, immunity, and neuroinflammation in stroke.

The lymphatic drainage system of the central nervous system (CNS) plays an important role in maintaining interstitial fluid balance and regulating immune responses and immune surveillance. The impaired lymphatic drainage system of the CNS might be involved in the onset and progression of various neurodegenerative diseases, neuroinflammation, and cerebrovascular diseases. A significant immune response and brain edema are observed after stroke, resulting from disrupted homeostasis in the brain. Thus, understanding the lymphatic drainage system of the CNS in stroke may lead to the development of new approaches for therapeutic interventions in the future. Here, we review recent evidence implicating the lymphatic drainage system of the CNS in stroke.

Construction of the Antheraea pernyi (Lepidoptera: Saturniidae) Multicapsid Nucleopolyhedrovirus Bacmid System.

In this study, we established the Antheraea pernyi multicapsid nucleopolyhedrovirus (AnpeNPV) bacmid system for the construction of a Bac-to-Bac expression system and the generation of virus mutants. The CopyRight pSMART BAC cloning vector harboring the chloramphenicol resistance gene was introduced into the AnpeNPV genome to produce the AnpeNPV bacmid that could be propagated in Escherichia coli with stable replication. The enhanced green fluorescent protein (EGFP) was successfully expressed in both Tn-Hi5 cells and A. pernyi pupae using the AnpeNPV Bac-to-Bac expression system. To generate the AnpeNPV mutants, we developed the AnpeNPV bacmid/λ Red recombination system that facilitated the deletion of viral genes from the AnpeNPV genome. The genes cathepsin and chitinase were deleted and a derivative AnpeNPV Bac-to-Bac expression system was constructed. Furthermore, we demonstrated that the novel expression system could be used to express human epidermal growth factor in A. pernyi pupae. Taken together, the AnpeNPV bacmid system provides a powerful tool to create the AnpeNPV Bac-to-Bac expression system for protein expression in A. pernyi pupae. Further, it helps to knock-out genes from the AnpeNPV genome with λ Red recombination system for identification of the role of viral genes involved in regulating gene expression, DNA replication, virion structure, and infectivity during the AnpeNPV infection process.

Sensory Glia Detect Repulsive Odorants and Drive Olfactory Adaptation.

Glia are typically considered as supporting cells for neural development and synaptic transmission. Here, we report an active role of a glia in olfactory transduction. As a polymodal sensory neuron in C. elegans, the ASH neuron is previously known to detect multiple aversive odorants. We reveal that the AMsh glia, a sheath for multiple sensory neurons including ASH, cell-autonomously respond to aversive odorants via G-protein-coupled receptors (GPCRs) distinct from those in ASH. Upon activation, the AMsh glia suppress aversive odorant-triggered avoidance and promote olfactory adaptation by inhibiting the ASH neuron via GABA signaling. Thus, we propose a novel two-receptor model where the glia and sensory neuron jointly mediate adaptive olfaction. Our study reveals a non-canonical function of glial cells in olfactory transduction, which may provide new insights into the glia-like supporting cells in mammalian sensory procession.

[Effect of electroacupuncture on recognition memory and levels of Aß, inflammatory factor proteins and aquaporin 4 in hippocampus of APP/PS1 double transgenic mice].

OBJECTIVE: To investigate the effect of electroacupuncture (EA) at "Baihui "(GV20) and "Shenshu "(BL23) on activation of glial cells, expression of inflammatory factor proteins and aquaporin 4 (AQP4)in the hippocampus of amyloid precursor protein/presenilin-1 (APP/PS1) transgenic mice, so as to explore its mechanisms underlying improvement of Alzheimer's disease(AD). METHODS: Twenty C57/BL6 background male APP695/PS1-dE9(APP/PS1) double transgenic mice (model group) and 20 wild type (WT) C57/BL6 mice (blank group) were respectively randomized into control and EA groups. EA (2 Hz/15 Hz, 1－2 mA) was applied to GV20 and bilateral BL23 for 30 min, once daily, 6 days a week for 4 weeks. The recognition memory ability was detected by novel object recognition tests in a behavior test box. The percentage of time spent in close interaction with novel object (C) relative to the total time was used to generate preference index. The contents of hippocampal ß amyloid protein (Aß)1-40 and Aß1-42 were assayed using ELISA, and the expression levels of glial fibrillary acidic protein (GFAP), ionic calcium binding receptor molecule-1 (Iba-1), interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) proteins in the hippocampus measured by Western blot. The activities of hippocampal astrocytes (GFAP-labelled cells), microglia (Iba-1-labelled cells) and the polarity expression of AQP4 (for removing Aß) were measured by immunohistochemistry. RESULTS: The preference index was significantly decreased in the model group relatively to the blank control group (P<0.05) and considerably increased in the model＋EA group relatively to the model group (P<0.05), suggesting an improvement of the recognition memory after EA. The contents of Aß1-40 and Aß1-42, immunoactivity of GFAP and Iba-1, expression levels of GFAP, Iba-1, IL-1ß, IL-6 and TNF-α proteins were significantly higher in the model group than in the blank control group (P<0.01，P<0.05), while the AQP4 immunoactivity was notably lower in the model group than in the blank control group (P<0.05). Compared with the model group, the levels of Aß1-40 and Aß1-42, GFAP, Iba-1, IL-1ß, IL-6 and TNF-α proteins, and the percentage of Aß plaque area were significantly decreased in the model＋EA group (P<0.01，P<0.05), and the immunoactivity of AQP4 was significantly increased in the mo-del＋EA group (P<0.05). No significant changes were found in the above-mentioned indexes in the blank＋EA group relevant to the blank control group (P>0.05)．. CONCLUSION: EA at GV20 and BL23 can reduce inflammatory reaction and Aß level, suppress activation of astrocytes and microglia, and up-regulate expression of AQP4 in the hippocampus tissue in APP/PS1 transgenic mice, which may contribute to its effect in improving recognition memory ability, suggesting a role of EA intervention in delaying the development of AD via promoting the drainage of Aß by the glymphatic system in the brain.

Meningeal lymphatics clear erythrocytes that arise from subarachnoid hemorrhage.

Extravasated erythrocytes in cerebrospinal fluid (CSF) critically contribute to the pathogenesis of subarachnoid hemorrhage (SAH). Meningeal lymphatics have been reported to drain macromolecules and immune cells from CSF into cervical lymph nodes (CLNs). However, whether meningeal lymphatics are involved in clearing extravasated erythrocytes in CSF after SAH remains unclear. Here we show that a markedly higher number of erythrocytes are accumulated in the lymphatics of CLNs and meningeal lymphatics after SAH. When the meningeal lymphatics are depleted in a mouse model of SAH, the degree of erythrocyte aggregation in CLNs is significantly lower, while the associated neuroinflammation and the neurologic deficits are dramatically exacerbated. In addition, during SAH lymph flow is increased but without significant lymphangiogenesis and lymphangiectasia. Taken together, this work demonstrates that the meningeal lymphatics drain extravasated erythrocytes from CSF into CLNs after SAH, while suggesting that modulating this draining may offer therapeutic approaches to alleviate SAH severity.

Construction of a Baculovirus Derivative to Produce Linearized Antheraea pernyi (Lepidoptera: Saturniidae) Multicapsid Nucleopolyhedrovirus Genomic DNA.

In the Antheraea pernyi multicapsid nucleopolyhedrovirus (AnpeNPV)-based expression vector system, the frequency of homologous recombination events between wild-type AnpeNPV DNA and the transfer vector is low, resulting in a small amount of recombinant virus. Previous reports have indicated that linearized baculovirus DNA can increase the proportion of recombinant virus relative to the total progeny. To improve the recombination efficiency, we constructed a linearized derivative of AnpeNPV, referred to as AnpeNPVPhEGFP-AvrII, in which egfp flanked by AvrII restriction sites was located at the polyhedrin locus and driven by the polyhedrin promoter. Linear AnpeNPV DNA was obtained by the treatment of AnpeNPVPhEGFP-AvrII genomic DNA with AvrII endonuclease. The infectivity and recombinogenic activity between the linearized and circular viral DNA were evaluated by quantitative real-time polymerase chain reactions. We demonstrated that the linearized AnpeNPV DNA produced only small numbers of infectious budded viruses, accounting for approximately 4.5% of the budded virus production of wild-type AnpeNPV DNA in A. pernyi pupae. However, the linearized AnpeNPV DNA substantially increased recombinant virus production after cotransfection with an appropriate transfer vector; relative abundance of the recombinant virus was approximately 5.5-fold higher than that of the wild-type AnpeNPV DNA in A. pernyi pupae. The linearization of AnpeNPV DNA will facilitate the purification of recombinant viruses using the AnpeNPV-based expression vector system and the construction of an AnpeNPV-based bacmid system.

Quantitative real-time PCR with high-throughput automatable DNA preparation for molecular screening of Nosema spp. in Antheraea pernyi.

Accurate diagnosis of pathogenic Nosema spp. in Antheraea pernyi samples is considered especially useful for reducing economic losses in sericulture and improving food safety by maintaining pathogen-free pupae. However, microscopy and immunologic methods have poor diagnostic sensitivity, while the more sensitive PCR methods remain costly and time-consuming for template preparation. To address this issue, we introduce a sensitive ALMS-qPCR method that combines fast, simple DNA extraction using Alkali Lysis followed by Magnetic bead Separation (ALMS) and quantitative real-time PCR (qPCR). This approach is especially fit for large-scale pathogen molecular screening, because the DNA preparation procedure is fast (<0.94 min per sample) and is high-throughput (performs on a 96-well plate). It is cost-effective, since the most expensive materials can be made in the lab and can be recycled, while the automated procedure can help to minimize labor cost. Though the DNA preparation procedure was substantially simplified, common PCR inhibitory factors were not observed. The sensitivity of ALMS-qPCR is high and the limit of detection is 0.045 parasites/µL. Large-scale screening of Nosema spp. in 3000 Antheraea pernyi samples confirmed the efficacy of the ALMS-qPCR method. Sensitivity is much higher than clinical microscopy, especially for host groups with low infection prevalence and levels. High-throughput ALMS-qPCR, combining automated DNA preparation and sensitive qPCR, provides an enhanced approach for pébrine screening and epidemiological studies. The application of ALMS-qPCR in the sericulture industry will help to strengthen pébrine control and breed pathogen-free species, which means much safer food provision and better genetic resource conservation.

Persistent Malfunction of Glymphatic and Meningeal Lymphatic Drainage in a Mouse Model of Subarachnoid Hemorrhage.

Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular event that often is followed by permanent brain impairments. It is necessary to explore the pathogenesis of secondary pathological damages in order to find effective interventions for improving the prognosis of SAH. Blockage of brain lymphatic drainage has been shown to worsen cerebral ischemia and edema after acute SAH. However, whether or not there is persistent dysfunction of cerebral lymphatic drainage following SAH remains unclear. In this study, autologous blood was injected into the cisterna magna of mice to establish SAH model. One week after surgery, SAH mice showed decreases in fluorescent tracer drainage to the deep cervical lymph nodes (dcLNs) and influx into the brain parenchyma after injection into the cisterna magna. Moreover, SAH impaired polarization of astrocyte aquaporin-4 (AQP4) that is a functional marker of glymphatic clearance and resulted in accumulations of Tau proteins as well as CD3+, CD4+, and CD8+ cells in the brain. In addition, pathological changes, including microvascular spasm, activation of glial cells, neuroinflammation, and neuronal apoptosis were observed in the hippocampus of SAH mice. Present results demonstrate persistent malfunction of glymphatic and meningeal lymphatic drainage and related neuropathological damages after SAH. Targeting improvement of brain lymphatic clearance potentially serves as a new strategy for the treatment of SAH.

Evaluation of Reference Genes for Normalization of RT-qPCR Gene Expression Data for Trichoplusia ni Cells During Antheraea pernyi (Lepidoptera: Saturniidae) Multicapsid Nucleopolyhedrovirus (AnpeNPV) Infection.

Baculovirus infection impacts global gene expression in the host cell, including the expression of housekeeping genes. Evaluation of candidate reference genes during a viral infection will inform the selection of appropriate reference gene(s) for the normalization of expression data generated by Reverse Transcription Quantitative Real-timePolymerase Chain Reaction (RT-qPCR). Antheraea pernyi multicapsid nucleopolyhedrovirus (AnpeNPV) is able to infect the High Five cells (Tn-Hi5). In the present study, 10 candidate reference genes were evaluated in AnpeNPV-infected Tn-Hi5 cells. Gene expression data were analyzed using geNorm, NormFinder, BestKeeper, and RefFinder. The candidate genes were further validated as reliable reference genes for RT-qPCR by analyzing the expression of three target genes. The results of data analysis using four statistical methods showed that RPS18 was the least stable among the candidate reference genes tested. 18S rRNA and 28S rRNA were not suitable as reference genes for RT-qPCR analysis in AnpeNPV-infected Tn-Hi5 cells. Comprehensive ranking of the 10 candidate reference genes by RefFinder analysis indicated that Ann B, c45128_g1, and ACT were the top three genes. Normalization of the expression of three target genes using the candidate reference genes indicated the same expression pattern when Ann B and c45128_g1 were used as reference genes, with slight differences in the relative expression at each infection time point. Overall, Ann B and c45128_g1 were recommended to be more suitable than the most commonly used reference genes, such as ACT, GAPDH, and TUB, for RT-qPCR data normalization in AnpeNPV-infected Tn-Hi5 cells up to 48 hpi.

LncRNA TATDN1 contributes to the cisplatin resistance of non-small cell lung cancer through TATDN1/miR-451/TRIM66 axis.

BACKGROUND: Chemoresistance has been considered to be a major obstacle for cancer therapy clinically. Long non-coding RNAs (LncRNAs) are asscociated with the development, prognosis and drug-resistance of non-small cell lung cancer (NSCLC). Whereas, the regulatory mechanism of lncRNA TATDN1 in the cisplatin resistance of NSCLC is still not clear. METHODS: The expression of TATDN1, miR-451 and TRIM66 in NSCLC tissues and cell lines were detected by qRT-PCR or western blot. Immunohistochemistry (IHC) assay was performed for the detection of TATDN1 expression profile. 88 patients who underwent cisplatin treatment were followed up to 60-months for the analysis of survival rate. MTT and Flow cytometry analysis were performed for the assessment of cell survival rate, proliferation and apoptosis. Bioinformatics, Dual-Luciferase reporter were employed to analyze the interaction among TATDN1, miR-451 and TRIM66. Xenograft tumor model was constructed to verify the role of TATDN1 in NSCLC treated with cisplatin (DDP) in vivo. RESULTS: TATDN1 and TRIM66 was significantly upregulated while miR-451 was downregulated in NSCLC tissues and cell lines, especially in DDP-resistant tumor tissues and cells. Survival rates of NSCLC patients with low TATDN1 expression were improved following DDP chemotherapy. TATDN1 upregulated TRIM66 expression via sponge for miR-451. Moreover, TATDN1 knockdown improved DDP-sensitivity in NSCLC patients by regulation of miR-451/TRIM66 axis. Finally, knockdown of TATDN1 improved the sensitivity of NSCLC to DDP in vivo. CONCLUSIONS: TATDN1 enhanced the DDP-tolerance of NSCLC cells by upregulating TRIM66 expression via sponging miR-451, hinting a novel regulatory pathway of chemoresistance in DDP-tolerant NSCLC cells and providing a potential therapeutic target for NSCLC patients with DDP-reistance.

Deep cervical lymph node ligation aggravates AD-like pathology of APP/PS1 mice.

The imbalance between production and clearance of amyloid-beta (Aß) is a key step in the onset and development of Alzheimer's disease (AD). Therefore, reducing Aß accumulation in the brain is a promising therapeutic strategy for AD. The recently discovered glymphatic system and meningeal lymphatic vasculature have been shown to be critical for the elimination of interstitial waste products, especially Aß, from the brain. In the present study, ligation of deep cervical lymph nodes was performed to block drainage of this system and explore the consequences on Aß-related pathophysiology. Five-month-old APP/PS1 mice and their wild-type littermates received deep cervical lymphatic node ligation. One month later, behavioral testing and pathological analysis were conducted. Results demonstrated that ligation of dcLNs exacerbated AD-like phenotypes of APP/PS1 mice, showing more severe brain Aß accumulation, neuroinflammation, synaptic protein loss, impaired polarization of aquaporin-4 and deficits in cognitive and exploratory behaviors. These results suggest that brain lymphatic clearance malfunction is one of the deteriorating factors in the progression of AD, and restoring its function is a potential therapeutic target against AD.

Enriched Physical Environment Attenuates Spatial and Social Memory Impairments of Aged Socially Isolated Mice.

Background: Social isolation in the elderly is one of the principal health risks in an aging society. Physical environmental enrichment is shown to improve sensory, cognitive, and motor functions, but it is unknown whether environmental enrichment can protect against brain impairments caused by social isolation. Methods: Eighteen-month-old mice were housed, either grouped or isolated, in a standard or enriched environment for 2 months, respectively. Behavioral tests were performed to evaluate cognitive functional and social interaction ability. Synaptic protein levels, myelination, neuroinflammation, brain derived neurotrophic factor, and NOD-like receptor protein 3 inflammasome signaling pathways were examined in the medial prefrontal cortex and hippocampus. Results: Isolated aged mice exhibited declines in spatial memory and social memory compared with age-matched littermates living within group housing. The aforementioned memory malfunctions were mitigated in isolated aged mice that were housed in a large cage with a running wheel and novel toys. Enriched housing prevented synaptic protein loss, myelination defects, and downregulation of brain derived neurotrophic factor, while also increasing interleukin 1 beta and tumor necrosis factor alpha in the medial prefrontal cortex and hippocampus of isolated mice. In addition, activation of glial cells and NOD-like receptor protein 3 inflammasomes was partially ameliorated in the hippocampus of isolated mice treated with physical environmental enrichment. Conclusions: These results suggest that an enriched physical environment program may serve as a nonpharmacological intervention candidate to help maintain healthy brain function of elderly people living alone.

Astroglial water channel aquaporin 4-mediated glymphatic clearance function: A determined factor for time-sensitive treatment of aerobic exercise in patients with Alzheimer's disease.

Currently, there are no effective drug therapies for Alzheimer's disease (AD). Thus, exploring new non-pharmacological strategies, including the neuroprotective mechanisms of aerobic exercise, to enhance therapeutic treatment of AD are essential. Previous studies have shown that the beneficial efficiency of aerobic exercise in the prevention and treatment of AD is time-sensitive, but its mechanism is not clear. Recent studies revealed that the water channel protein aquaporin 4 (AQP4) mediates the glymphatic system to clear interstitial solutes, including ß-amyloid, from the brain. More recently, voluntary exercise has been shown to promote glymphatic clearance function in mice. However, glymphatic function is reduced in the mid- or late-stage of AD due to the loss of the polarity distribution of AQP4. Based on this, we hypothesized that AQP4-mediated glymphatic system clearance function is a determining factor for time-sensitive treatment of aerobic exercise in patients with AD. While further studies are necessary, the potential results are important for elucidating the new pro-cognitive mechanism of aerobic exercise, but also help to establish a new strategy for treatment of AD via regulation of glymphatic clearance function by targeting AQP4.

Neural differentiation of human Wharton's jelly-derived mesenchymal stem cells improves the recovery of neurological function after transplantation in ischemic stroke rats.

Human Wharton's jelly-derived mesenchymal stem cells (hWJ-MSCs) have excellent proliferative ability, differentiation ability, low immunogenicity, and can be easily obtained. However, there are few studies on their application in the treatment of ischemic stroke, therefore their therapeutic effect requires further verification. In this study, hWJ-MSCs were transplanted into an ischemic stroke rat model via the tail vein 48 hours after transient middle cerebral artery occlusion. After 4 weeks, neurological functions of the rats implanted with hWJ-MSCs were significantly recovered. Furthermore, many hWJ-MSCs homed to the ischemic frontal cortex whereby they differentiated into neuron-like cells at this region. These results confirm that hWJ-MSCs transplanted into the ischemic stroke rat can differentiate into neuron-like cells to improve rat neurological function and behavior.