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1.
Micromachines (Basel) ; 15(4)2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38675325

ABSTRACT

Real-time DOA (direction of arrival) estimation of surface or underwater targets is of great significance to the research of marine environment and national security protection. When conducting real-time DOA estimation of underwater targets, it can be difficult to extract the prior characteristics of noise due to the complexity and variability of the marine environment. Therefore, the accuracy of target orientation in the absence of a known noise is significantly reduced, thereby presenting an additional challenge for the DOA estimation of the marine targets in real-time. Aiming at the problem of real-time DOA estimation of acoustic targets in complex environments, this paper applies the MEMS vector hydrophone with a small size and high sensitivity to sense the conditions of the ocean environment and change the structural parameters in the adaptive adjustments system itself to obtain the desired target signal, proposes a signal processing method when the prior characteristics of noise are unknown. Theoretical analysis and experimental verification show that the method can achieve accurate real-time DOA estimation of the target, achieve an error within 3.1° under the SNR (signal-to-noise ratio) of the X channel of -17 dB, and maintain a stable value when the SNR continues to decrease. The results show that this method has a very broad application prospect in the field of ocean monitoring.

2.
Biomed Pharmacother ; 173: 116342, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38430635

ABSTRACT

BACKGROUND: Neuroinflammation is responsible for neuropsychiatric dysfunction following acute brain injury and neurodegenerative diseases. This study describes how a hypoxia-inducible factor prolyl hydroxylase (HIF-PHD) inhibitor FG-4592 prevents the lipopolysaccharide (LPS)-induced acute neuroinflammation in microglia. METHODS: The distribution of FG-4592 in mouse brain tissues was determined by collision-induced dissociation tandem mass spectrometry. Microglial activation in the hippocampus was analyzed by immunofluorescence. Moreover, we determined the activation of HIF-1 and nuclear factor-κB (NF-κB) signaling pathways, proinflammatory responses using molecular biological techniques. Transcriptome sequencing and BNIP3 silencing were conducted to explore signaling pathway and molecular mechanisms underlying FG-4592 anti-inflammatory activity. RESULTS: FG-4592 was transported into the brain tissues and LPS increased its transportation. FG-4592 promoted the expression of HIF-1α and induced the downstream gene transcription in the hippocampus. Administration with FG-4592 significantly inhibited microglial hyperactivation and decreased proinflammatory cytokine levels following LPS treatment in the hippocampus. The LPS-induced inflammatory responses and the NF-κB signaling pathway were also downregulated by FG-4592 pretreatment in microglial cells. Mechanistically, Venn diagram analysis of transcriptomic changes of BV2 cells identified that BNIP3 was a shared and common differentially expressed gene among different treatment groups. FG-4592 markedly upregulated the protein levels of BNIP3 in microglia. Importantly, BNIP3 knockdown aggravated the LPS-stimulated inflammatory responses and partially reversed the protection of FG-4592 against microglial inflammatory signaling and microglial activation in the mouse hippocampus. CONCLUSIONS: FG-4592 alleviates neuroinflammation through facilitating microglial HIF-1/BNIP3 signaling pathway in mice. Targeting HIF-PHD/HIF-1/BNIP3 axis is a promising strategy for the development of anti-neuroinflammation drugs.


Subject(s)
NF-kappa B , Prolyl-Hydroxylase Inhibitors , Mice , Animals , NF-kappa B/metabolism , Microglia/metabolism , Prolyl-Hydroxylase Inhibitors/metabolism , Neuroinflammatory Diseases , Lipopolysaccharides/toxicity , Lipopolysaccharides/metabolism , Signal Transduction , Hypoxia-Inducible Factor 1/metabolism
3.
Sheng Wu Gong Cheng Xue Bao ; 39(10): 4234-4245, 2023 Oct 25.
Article in Chinese | MEDLINE | ID: mdl-37877402

ABSTRACT

The aim of this study was to investigate the growth characteristics of primarily cultured astrocytes and microglia of different generations and then optimize the method for obtaining primary astrocytes and microglia effectively. Primarily cultured microglia were isolated and purified from the cortices of neonatal mice. The proliferation curve of mixed glia cells was measured by Cell Counting Kit-8 (CCK-8) assay, the proportion of astrocytes and microglia was detected by flow cytometry, and the polarization of the two types of glia cells was identified by immunofluorescence staining. Cell growth results showed that the mixed glia cells of P0 and P1 generation had the best proliferative activity; 97.3% of the high purity microglia could be obtained by mechanical shaking at 170 r/min for 30 min, and there was no significant difference in the morphology of ionized calcium-binding adapter molecule 1 (Iba-1) positive microglia and the proportion of M1 and M2 phenotype among the P0, P1 and P2 generations of microglia isolated by the above methods. Moreover, 95.7 % of the high purity astrocytes could be obtained by astrocyte cell surface antigen-2 (ACSA-2) magnetic beads separation, and there was no significant difference in the morphology of glial fibrillary acidic protein (GFAP) positive astrocyte and the proportion of A1 and A2 phenotype among the P0, P1 and P2 generations of astrocyte isolated by the above methods. Taken together, this study observed the growth characteristics of primarily cultured microglia and astrocyte in vitro, and then proved the best generations for purifying microglia and astrocytes. Finally, we optimized the methods of obtaining microglia and astrocyte, and verified that continuous culture within 2 generations will not affect the functional phenotypes of glia cells. These results provide technical support for studying the molecular mechanism of inflammation-associated diseases in nervous system.


Subject(s)
Astrocytes , Microglia , Mice , Animals , Astrocytes/metabolism , Microglia/metabolism , Cell Count , Flow Cytometry/methods , Cell Proliferation , Cells, Cultured
4.
Pharmaceuticals (Basel) ; 16(8)2023 Aug 14.
Article in English | MEDLINE | ID: mdl-37631068

ABSTRACT

Neuroinflammation is a common pathogenetic sign of depression and is closely linked to the development of depression. Many clinical anti-inflammatory drugs act as antidepressants by reducing the neuroinflammatory response. Previous research found that gypenosides and their bioactive compound gypenoside-14 (GP-14) had neuroprotective effects against hypoxia-induced injury and reduced neuroinflammation-related high-altitude cerebral edema. Here we investigated the effects of GP-14 on the lipopolysaccharide (LPS)-induced depression-like behavior model. LPS (0.5 mg/kg) was injected into mice intraperitoneally for 7 consecutive days to induce depression-like behavior, which is considered a model for the exacerbation of depression. GP-14 in the amount of 100 mg/kg was simultaneously administered by gavage for 7 days. In the LPS-induced depression model, GP-14 not only attenuated depression-like behavior but also improved the anxiety-like behavior of the mice. Additionally, GP-14 treatment mitigated learning and cognitive decline in depressed mice. ELISA and immunofluorescence staining results revealed that GP-14 inhibited the upregulation of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6), and suppressed the activation of astrocytes induced with LPS, indicating its potent anti-inflammatory effect. GP-14 pretreatment in C8 cells and primary astrocytes can inhibit the activation of the NF-κB signaling pathway and downregulate the levels of pro-inflammatory factors. In summary, our findings showed that GP-14 had significant anti-inflammation and anti-depression properties; thus, GP-14 could be a promising lead compound for treating depression.

5.
Int J Immunopathol Pharmacol ; 37: 3946320231177189, 2023.
Article in English | MEDLINE | ID: mdl-37188519

ABSTRACT

INTRODUCTION: High-altitude cerebral edema (HACE) is considered to be the end-stage of acute mountain sickness (AMS); however, its pathophysiological mechanism remains unknown. Increasing evidences support that inflammation is an important risk factor for the occurrence of HACE. Including our published papers, previous studies demonstrated that the levels of IL-6, IL-1ß, and TNF-α in both serum and hippocampus were increased in the mouse HACE model induced by LPS stimulation combined with hypobaric hypoxia exposure; however, the expression profile of other cytokines and chemokines remains unknown. OBJECTIVE: This study was to analyze the expression profile of cytokines and chemokines in the HACE model. METHODS: The mouse HACE model was established by LPS stimulation combined with hypobaric hypoxia exposure (LH). The mice were divided into the normoxic group, LH-6 h group, LH-1 d group, and LH-7 d group. Brain water content (BWC) was determined using the wet/dry weight ratio. The levels of 30 cytokines and chemokines in the serum and hippocampal tissue were detected using LiquiChip. The mRNA expression of cytokines and chemokines in hippocampal tissue were determined by q-PCR. RESULTS: In the current study, we found that the brain water content was increased after the combinational treatment of LPS and hypobaric hypoxia. The results of LiquiChip showed that, in the serum and hippocampal tissue, most factors in all 30 cytokines and chemokines were dramatically upregulated at 6 h, and then declined at the 1st d and 7th d. Among these factors, G-CSF, M-CSF, MCP-1, KC, MIG, Eotaxin, Rantes, IP10, IL-6, MIP-2, and MIP-1ß were all increased in both serum and hippocampal tissue at 6 h. In addition, the results of q-PCR showed the mRNA levels of G-CSF, MCP-1, KC, MIG, Eotaxin, Rantes, IP10, IL-6, MIP-2, and MIP-1ß in hippocampal tissue were dramatically upregulated at 6 h. CONCLUSION: This study showed that the dynamic expression profile of 30 cytokines and chemokines in a mouse HACE model induced by LPS plus hypobaric hypoxia. The levels of G-CSF, MCP-1, KC, MIG, Eotaxin, Rantes, IP10, IL-6, MIP-2, and MIP-1ß in both serum and hippocampus were significantly increased at 6 h, which may be involved in the occurrence and development of HACE.


Subject(s)
Altitude Sickness , Brain Edema , Mice , Animals , Cytokines/metabolism , Altitude Sickness/complications , Chemokine CCL5 , Chemokine CCL4 , Interleukin-6 , Chemokine CXCL10 , Altitude , Brain Edema/etiology , Lipopolysaccharides , Hypoxia/complications , Granulocyte Colony-Stimulating Factor , Water , RNA, Messenger
6.
Exp Ther Med ; 25(3): 123, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36845947

ABSTRACT

Hypoxia and neuroinflammation are key risk factors involved in various pathophysiological neural disorders. Hypoxia can aggravate neuroinflammation in vitro and in vivo; however, the underlying mechanisms remain unknown. In the present study, hypoxia [either 3 or 1% oxygen (O2)] increased lipopolysaccharide (LPS)-induced expression of the IL-6, IL-1ß and TNF-α proinflammatory cytokines in BV2 cells. At the molecular level, both hypoxia and FG-4592, an hypoxia inducible factor 1 pathway activator, effectively induced cyclooxygenase-2 (COX-2) expression. The COX-2 inhibitor celecoxib significantly reduced the expression of cytokines induced by LPS under hypoxic conditions. Additionally, the administration of celecoxib inhibited the activation of microglia as well as cytokine expression in mice administered with hypoxia exposure and LPS injection. The present data demonstrated that COX-2 is involved in the hypoxia-induced aggravation of neuroinflammation stimulated by LPS.

7.
Toxicol Appl Pharmacol ; 448: 116092, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35654276

ABSTRACT

Gypenosides are major bioactive ingredients of G. pentaphyllum. In our previous study, we found that gypenosides had neuroprotective effects against hypoxia-induced injury. In the current study, we focused on the protective effects of gypenoside-14 (GP-14), which is one of the newly identified bioactive components, on neuronal injury caused by severe hypoxia (0.3% O2). The results showed that GP-14 pretreatment alleviated the cell viability damage and apoptosis induced by hypoxia in PC12 cells. Moreover, GP-14 pretreatment also attenuated primary neuron injuries under hypoxic conditions. Additionally, GP-14 pretreatment significantly ameliorated neuronal damage in the hippocampal region induced by high-altitude cerebral edema (HACE). At the molecular level, GP-14 pretreatment reversed the decreased activities of the AKT and ERK signaling pathways caused by hypoxia in PC12 cells and primary neurons. To comprehensively explore the possible mechanisms, transcriptome sequencing was conducted, and these results indicated that GP-14 could alter the transcriptional profiles of primary neuron. Taken together, our results suggest that GP-14 acts as a neuroprotective agent to protect against neuronal damage induced by severe hypoxia and it is a promising compound for the development of neuroprotective drugs.


Subject(s)
MAP Kinase Signaling System , Neurons , Neuroprotective Agents , Proto-Oncogene Proteins c-akt , Animals , Apoptosis/drug effects , Cell Hypoxia/drug effects , Gene Expression Profiling , Gynostemma/chemistry , MAP Kinase Signaling System/drug effects , Neurons/drug effects , Neurons/metabolism , Neurons/pathology , Neuroprotective Agents/pharmacology , Plant Extracts/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Rats
8.
Exp Neurol ; 354: 114116, 2022 08.
Article in English | MEDLINE | ID: mdl-35584741

ABSTRACT

NB-3, a member of the contactin/F3 subgroup in the immunoglobulin superfamily, plays an important role in neural development and injury recovery. The blood brain barrier (BBB) is typically involved in the pathophysiology of neural disorders, such as hypoxic-ischemic brain injury. Our previous research found that NB-3 protects against brain damage in a mouse stroke model. However, its role in high-altitude disorders caused by hypobaric hypoxia exposure remains unknown. In the present study, we found that NB-3 was expressed in brain microvascular endothelial cells (BMECs) and responded to hypoxia stimulation. Conditional knockout of NB-3 in endothelial cells increased BBB leakage and downregulated tight junction proteins in vivo. NB-3 deficiency promoted the downregulation of tight junction proteins under Lipopolysaccharide (LPS)/hypoxia stimulation. Conversely, overexpression or supplementation with NB-3 alleviated endothelial barrier injuries. Transcriptome sequencing showed that NB-3 regulated various cell attachment genomic changes, including the Notch signaling pathway. Blocking the Notch signaling pathway increased VEGF/VEGFR2 pathway activation induced by LPS/hypoxia. Collectively, we present evidence that NB-3 plays key roles in maintaining BBB integrity under high-altitude cerebral edema conditions.


Subject(s)
Altitude Sickness , Brain Edema , Cell Adhesion Molecules, Neuronal/metabolism , Altitude , Animals , Blood-Brain Barrier/metabolism , Brain Edema/etiology , Brain Edema/metabolism , Disease Models, Animal , Endothelial Cells/metabolism , Hypoxia/metabolism , Lipopolysaccharides , Mice , Tight Junction Proteins/metabolism
9.
J Agric Food Chem ; 70(13): 4030-4043, 2022 Apr 06.
Article in English | MEDLINE | ID: mdl-35343224

ABSTRACT

Goat milk contains a rich source of nutrients, especially unsaturated fatty acids. However, the regulatory mechanism of milk fat and fatty acid synthesis remains unclear. Stearoyl-CoA desaturase 1 (SCD1) is the key enzyme catalyzing monounsaturated fatty acid synthesis and is essential for milk lipid metabolism. To explore milk lipid synthesis mechanism in vivo, SCD1-knockout goats were generated through CRISPR/Cas9 technology for the first time. SCD1 deficiency did not influence goat growth or serum biochemistry. Plasma phosphatidylcholines increased by lipidomics after SCD1 knockout in goats. Whole-blood RNA-seq indicated alterations in biosynthesis of unsaturated fatty acid synthesis, cAMP, ATPase activity, and Wnt signaling pathways. In SCD1-knockout goats, milk fat percentage and unsaturated fatty acid levels were reduced but other milk components were unchanged. Milk lipidomics revealed decreased triacylglycerols and diacylglycerols levels, and the differential abundance of lipids were enriched in glycerolipid, glycerophospholipids, and thermogenesis metabolism pathways. In milk fat globules, the expression levels of genes related to fatty acid and TAG synthesis including SREBP1 were reduced. ATP content and AMPK activity were promoted, and p-p70S6K protein level was suppressed in SCD1-knockout goat mammary epithelial cells, suggesting that SCD1 affected milk lipid metabolism by influencing AMPK-mTORC1/p70S6K-SREBP1 pathway. The integrative analysis of gene expression levels and lipidomics of milk revealed a crucial role of SCD1 in glycerolipids and glycerophospholipids metabolism pathways. Our observations indicated that SCD1 regulated the synthesis of milk fat and unsaturated fatty acid in goat by affecting lipid metabolism gene expression and lipid metabolic pathways. These findings would be essential for improving goat milk nutritional value which is beneficial to human health.


Subject(s)
Goats , Milk , Stearoyl-CoA Desaturase , Animals , CRISPR-Cas Systems , Fatty Acids/metabolism , Fatty Acids, Unsaturated/metabolism , Goats/metabolism , Milk/chemistry , Stearoyl-CoA Desaturase/genetics , Stearoyl-CoA Desaturase/metabolism
10.
Int Immunopharmacol ; 107: 108675, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35299003

ABSTRACT

BACKGROUND: Neuroinflammation caused by peripheral lipopolysaccharides (LPS) under hypoxia is a key contributor to the development of high altitude cerebral edema (HACE). Our previous studies have shown that gypenosides and their bioactive compounds prevent hypoxia-induced neural injuries in vitro and in vivo. However, their effect on neuroinflammation-related HACE remains to be illustrated. The present study aimed to investigate the effects of GP-14 in HACE mouse model. METHODS: HACE mice were treated with GP-14 (100 and 200 mg/kg) for 7 days. After the treatments, the level of serum inflammation cytokines and the transcription of inflammatory factors in brain tissue were determined. The activation of microglia, astrocyte and the changes of IgG leakage and the protein levels of tight junction proteins were detected. Furthermore, the inflammatory factors and nuclear factor-κB (NF-κB) signaling pathway in BV-2 cells and primary microglia were detected. RESULTS: GP-14 pretreatment alleviated both the serum and neural inflammatory responses caused by LPS stimulation combined with hypobaric hypoxia exposure. In addition, GP-14 pretreatment inhibited microglial activation, accompanied by a decrease in the M1 phenotype and an increase in the M2 phenotype. Moreover, the disruption of the blood brain barrier (BBB) integrity, including increased IgG leakage and decreased expression of tight junction proteins, was attenuated by GP-14 pretreatment. Based on the BV-2 and primary microglial models, the inflammatory response and activation of the NF-κB signaling pathway were also inhibited by GP-14 pretreatment. CONCLUSION: Taken together, our results demonstrated that GP-14 exhibited prominent protective roles against neuroinflammation and BBB disruption in a mouse HACE model. GP-14 could be a potential choice for the treatment of HACE in the future.


Subject(s)
Altitude Sickness , Brain Edema , Altitude , Altitude Sickness/complications , Altitude Sickness/metabolism , Animals , Blood-Brain Barrier , Brain Edema/drug therapy , Disease Models, Animal , Gynostemma , Hypoxia/complications , Immunoglobulin G/metabolism , Lipopolysaccharides/pharmacology , Mice , Microglia , NF-kappa B/metabolism , Neuroinflammatory Diseases , Plant Extracts , Signal Transduction , Tight Junction Proteins/metabolism
11.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 38(5): 401-405, 2022 Sep.
Article in Chinese | MEDLINE | ID: mdl-37088741

ABSTRACT

OBJECTIVE: To investigate the effects of blocking lactate synthesis on the HT22 cell injuries caused by hypoxia. METHODS: 2-deoxy-D-glucose (2-DG) is a non-metabolized glucose analogue that can inhibit lactate synthesis by blocking glycolysis. HT22 cells were divided into 4 groups: Control group, 2-DG group, Hypoxia group and 2-DG+Hypoxia group. The cells in control group and 2-DG treatment group were cultured in a 37℃, 5% CO2 incubator, and thecells in hypoxia group and 2-DG + Hypoxia group were cultured in a hypoxia incubator. The concentrations of 2-DG were 2.5 and 5 mmol/L, the concentration of oxygen was 0.3%, and the treatment time was 24 h. Cell activity was detected by CCK-8 assay, the levels of lactate in cell culture medium were detected by spectrophotometry, cell morphology was observed by fluorescence staining, the level of reactive oxygen species (ROS) was detected by flow cytometry, and the activities of superoxide dismutase (SOD) and catalase (CAT) were determined by enzyme activity kits. The protein expression levels of p-p38, t-p38 and ß-actin were detected by Western blot. RESULTS: Compared with that in control group, the lactate level in culture medium and cell activity were decreased significantly (P<0.01), the number of adherent cells was decreased, the level of ROS was increased (P<0.01), and the enzyme activity of CAT was decreased (P<0.05) in the 2-DG group. In the hypoxia group, the level of lactate in the culture medium was increased significantly (P<0.01), the cell activity was decreased (P<0.01), the number of adherent cells was decreased, the ROS levels were increased (P<0.01), and the enzyme activities of CAT and SOD were decreased (P<0.01 or P<0.05). In 2-DG+Hypoxia group, the level of lactate was decreased significantly (P<0.05), the cell viability was decreased significantly (P<0.01), the number of cells was decreased significantly, and the ability of adhere to the wall was weakened significantly. The level of ROS was increased significantly (P<0.01), the enzyme activities of CAT and SOD were decreased significantly (P<0.01), the protein expression level of p-p38 was increased significantly (P<0.05), and there was no change in t-p38. Compared with hypoxia groups, in 2-DG combined with hypoxia group, the level of lactate induced by hypoxia, the cell activity, and the enzyme activity level of CAT were decreased significantly (all P<0.01), while the level of ROS was increased significantly (P< 0.01). CONCLUSION: Blocking lactate can reduce the cell activity level under hypoxia and aggravate the oxidative stress injury of HT22 cells. The mechanisms may be related to increasing ROS level and activating p38 signal pathway.


Subject(s)
Hypoxia , Lactic Acid , Humans , Reactive Oxygen Species/metabolism , Hypoxia/metabolism , Oxidative Stress , Neurons , Superoxide Dismutase/metabolism , Deoxyglucose/metabolism , Deoxyglucose/pharmacology , Apoptosis
12.
Front Psychol ; 12: 809736, 2021.
Article in English | MEDLINE | ID: mdl-35002901

ABSTRACT

With the development of big data technology, the privacy concerns of face recognition have become the most critical social issue in the era of information sharing. Based on the perceived ease of use, perceived usefulness, social cognition, and cross-cultural aspects, this study analyses the privacy of face recognition and influencing factors. The study collected 518 questionnaires through the Internet, SPSS 25.0 was used to analyze the questionnaire data as well as evaluate the reliability of the data, and Cronbach's alpha (α coefficient) was used to measure the data in this study. Our findings demonstrate that when users perceive the risk of their private information being disclosed through face recognition, they have greater privacy concerns. However, most users will still choose to provide personal information in exchange for the services and applications they need. Trust in technology and platforms can reduce users' intention to put up guards against them. Users believe that face recognition platforms can create secure conditions for the use of face recognition technology, thus exhibiting a higher tendency to use such technology. Although perceived ease of use has no significant positive impact on the actual use of face recognition due to other external factors, such as accuracy and technology maturity, perceived usefulness still has a significant positive impact on the actual use of face recognition. These results enrich the literature on the application behavior of face recognition and play an important role in making better use of face recognition by social individuals, which not only facilitates their daily life but also does not disclose personal privacy information.

13.
Front Cell Neurosci ; 14: 611764, 2020.
Article in English | MEDLINE | ID: mdl-33362475

ABSTRACT

The importance of hypoxia in the pathophysiology of inflammatory bowel disease (IBD) is increasingly being realized; also, hypoxia seems to be an important accelerator of brain inflammation, as has been reported by our group and others. IBD is a chronic intestinal disorder that leads to the development of inflammation, which is related to brain dysfunction. However, no studies have reported whether hypoxia is associated with IBD-induced neuroinflammation. Therefore, the objective of the present study was to determine whether hypoxia augments cerebral inflammation in a DSS-induced colitis mouse model. The mouse model was developed using 3% DSS for five days combined with exposure to hypoxic conditions (6,000 m) for two days. Mice were randomly divided into four groups: control group, DSS group, hypoxia group, and DSS plus hypoxia group. The results demonstrated that DSS combined with hypoxia resulted in up-regulation of colonic and plasmatic proinflammatory cytokines. Meanwhile, DSS plus hypoxia increased expression of Iba1, which is a marker of activated microglia, accompanied by increased expression of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) in the brain. Moreover, the expression of tight junction proteins, such as zonula occludens-1 (ZO-1), occludin, and claudin-5, was markedly downregulated. The current study provides new insight into how hypoxia exposure induces excessive inflammatory responses andpathophysiological consequences in the brain in a DSS-induced colitis model.

14.
Proc Natl Acad Sci U S A ; 117(32): 19578-19589, 2020 08 11.
Article in English | MEDLINE | ID: mdl-32727894

ABSTRACT

The CreER/LoxP system is widely accepted to track neural lineages and study gene functions upon tamoxifen (TAM) administration. We have observed that prenatal TAM treatment caused high rates of delayed delivery and fetal mortality. This substance could produce undesired results, leading to data misinterpretation. Here, we report that administration of TAM during early stages of cortical neurogenesis promoted precocious neural differentiation, while it inhibited neural progenitor cell (NPC) proliferation. The TAM-induced inhibition of NPC proliferation led to deficits in cortical neurogenesis, dendritic morphogenesis, synaptic formation, and cortical patterning in neonatal and postnatal offspring. Mechanistically, by employing single-cell RNA-sequencing (scRNA-seq) analysis combined with in vivo and in vitro assays, we show TAM could exert these drastic effects mainly through dysregulating the Wnt-Dmrta2 signaling pathway. In adult mice, administration of TAM significantly attenuated NPC proliferation in both the subventricular zone and the dentate gyrus. This study revealed the cellular and molecular mechanisms for the adverse effects of TAM on corticogenesis, suggesting that care must be taken when using the TAM-induced CreER/LoxP system for neural lineage tracing and genetic manipulation studies in both embryonic and adult brains.


Subject(s)
Brain/drug effects , Neurogenesis/drug effects , Prenatal Exposure Delayed Effects/pathology , Tamoxifen/adverse effects , Animals , Brain/embryology , Brain/pathology , Cell Differentiation , Cell Proliferation , Dentate Gyrus/drug effects , Dentate Gyrus/pathology , Female , Lateral Ventricles/drug effects , Lateral Ventricles/pathology , Mice , Neural Stem Cells/drug effects , Neural Stem Cells/pathology , Pregnancy , Prenatal Exposure Delayed Effects/chemically induced , RNA-Seq , Single-Cell Analysis , Transcription Factors/metabolism , Wnt Signaling Pathway/drug effects
15.
Micromachines (Basel) ; 10(10)2019 Sep 29.
Article in English | MEDLINE | ID: mdl-31569481

ABSTRACT

Triboelectric nanogenerators with the function of harvesting human motion energy have attracted wide attention. Here, we demonstrate a shared-electrode and nested-tube structure triboelectric nanogenerator (SNTN) for harvesting human motion energy. The design of the SNTN employs flexible silicone rubber as the negative friction material and Ni-coated polyester conductive textile as the positive friction material and the electrode material. The entire structure consists of an inner triboelectric unit and an outer triboelectric unit. The inner triboelectric unit is formed by a hollow inner tube and a hollow middle tube, while the hollow middle tube and a hollow outer tube constitute the outer triboelectric unit. The hollow middle tube is used as the shared tube, and the electrode in the middle tube is used as the shared electrode of the two triboelectric units. Our research demonstrates that the output performance of the SNTN was improved significantly compared with a single triboelectric unit due to the cooperation of the two triboelectric units. When the SNTN is pressed by 300 N external force, output open-circuit voltage of 180 V and output short-circuit current of 8.5 µA can be obtained. The output electrical energy can light up 31 light-emitting diodes (LEDs) connected serially (displaying "XZTC") and can drive a digital clock after rectifying storage, which shows application prospects in the field of illuminating devices and portable electronics.

16.
Protein Cell ; 10(8): 566-582, 2019 08.
Article in English | MEDLINE | ID: mdl-29956125

ABSTRACT

The mammalian central nervous system (CNS) is considered an immune privileged system as it is separated from the periphery by the blood brain barrier (BBB). Yet, immune functions have been postulated to heavily influence the functional state of the CNS, especially after injury or during neurodegeneration. There is controversy regarding whether adaptive immune responses are beneficial or detrimental to CNS injury repair. In this study, we utilized immunocompromised SCID mice and subjected them to spinal cord injury (SCI). We analyzed motor function, electrophysiology, histochemistry, and performed unbiased RNA-sequencing. SCID mice displayed improved CNS functional recovery compared to WT mice after SCI. Weighted gene-coexpression network analysis (WGCNA) of spinal cord transcriptomes revealed that SCID mice had reduced expression of immune function-related genes and heightened expression of neural transmission-related genes after SCI, which was confirmed by immunohistochemical analysis and was consistent with better functional recovery. Transcriptomic analyses also indicated heightened expression of neurotransmission-related genes before injury in SCID mice, suggesting that a steady state of immune-deficiency potentially led to CNS hyper-connectivity. Consequently, SCID mice without injury demonstrated worse performance in Morris water maze test. Taken together, not only reduced inflammation after injury but also dampened steady-state immune function without injury heightened the neurotransmission program, resulting in better or worse behavioral outcomes respectively. This study revealed the intricate relationship between immune and nervous systems, raising the possibility for therapeutic manipulation of neural function via immune modulation.


Subject(s)
Gene Expression Profiling/methods , Recovery of Function/immunology , Spinal Cord Injuries/immunology , Animals , Mice , Mice, Inbred C57BL , Mice, SCID
17.
Protein Cell ; 9(4): 351-364, 2018 04.
Article in English | MEDLINE | ID: mdl-28748452

ABSTRACT

Aging associated cognitive decline has been linked to dampened neural stem/progenitor cells (NSC/NPCs) activities manifested by decreased proliferation, reduced propensity to produce neurons, and increased differentiation into astrocytes. While gene transcription changes objectively reveal molecular alterations of cells undergoing various biological processes, the search for molecular mechanisms underlying aging of NSC/NPCs has been confronted by the enormous heterogeneity in cellular compositions of the brain and the complex cellular microenvironment where NSC/NPCs reside. Moreover, brain NSC/NPCs themselves are not a homogenous population, making it even more difficult to uncover NSC/NPC sub-type specific aging mechanisms. Here, using both population-based and single cell transcriptome analyses of young and aged mouse forebrain ependymal and subependymal regions and comprehensive "big-data" processing, we report that NSC/NPCs reside in a rather inflammatory environment in aged brain, which likely contributes to the differentiation bias towards astrocytes versus neurons. Moreover, single cell transcriptome analyses revealed that different aged NSC/NPC subpopulations, while all have reduced cell proliferation, use different gene transcription programs to regulate age-dependent decline in cell cycle. Interestingly, changes in cell proliferation capacity are not influenced by inflammatory cytokines, but likely result from cell intrinsic mechanisms. The Erk/Mapk pathway appears to be critically involved in regulating age-dependent changes in the capacity for NSC/NPCs to undergo clonal expansion. Together this study is the first example of using population and single cell based transcriptome analyses to unveil the molecular interplay between different NSC/NPCs and their microenvironment in the context of the aging brain.


Subject(s)
Aging/genetics , Cell Differentiation/genetics , Gene Expression Regulation/genetics , Transcriptome/genetics , Animals , Astrocytes/cytology , Astrocytes/metabolism , Brain/cytology , Brain/metabolism , Cell Division/genetics , Cell Proliferation/genetics , Mice , Neural Stem Cells/metabolism , Single-Cell Analysis , Stem Cells/cytology , Stem Cells/metabolism
18.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(10): 1107-11, 2015 Oct.
Article in Chinese | MEDLINE | ID: mdl-26483234

ABSTRACT

OBJECTIVE: To study the distribution of polymorphism of c.212-37insC (rs3832879) in intron 1 of fibroblast growth factor 23 (FGF23) gene and its association with Kawasaki disease (KD) and coronary artery lesions (CAL). METHODS: Forty children with KD were enrolled in this study, among whom 16 children had concurrent CAL. Twenty-six age-matched healthy children were enrolled as controls. PCR and gene sequencing were applied to explore the distribution of polymorphism of c.212-37insC (rs3832879) in FGF23 gene in KD patients and controls. RESULTS: Among 40 children with KD, 14 (35%) carried the polymorphism of c.212-37insC (rs3832879) in FGF23 gene; among 26 controls, 6 (23%) carried such polymorphism. There was no significant difference in genotype distribution at this locus between the two groups (P=0.30). Among 16 children with CAL, 9 (56%) carried the polymorphism at this locus; among 24 children without CAL, 5 (21%) carried such polymorphism. As for the comparison of two subgroups with and without CAL, the difference in genotype distribution at this locus had statistical significance (P=0.02, OR=4.89, 95% CI: 1.21-19.71). CONCLUSIONS: The polymorphism of c.212-37insC (rs3832879) in FGF23 gene may not be associated with the pathogenesis of childhood KD, but it may be associated with the development of CAL in children with KD.


Subject(s)
Coronary Artery Disease/genetics , Fibroblast Growth Factors/genetics , Mucocutaneous Lymph Node Syndrome/genetics , Polymorphism, Genetic , Child , Child, Preschool , Coronary Artery Disease/etiology , Female , Fibroblast Growth Factor-23 , Humans , Infant , Male , Mucocutaneous Lymph Node Syndrome/etiology , Polymerase Chain Reaction
19.
Rev Sci Instrum ; 85(5): 053901, 2014 May.
Article in English | MEDLINE | ID: mdl-24880381

ABSTRACT

We present the realization of a mesoscopic imaging technique, namely, the Magnetoelectric Force Microscopy (MeFM), for visualization of local magnetoelectric effect. The basic principle of MeFM is the lock-in detection of local magnetoelectric response, i.e., the electric field-induced magnetization, using magnetic force microscopy. We demonstrate MeFM capability by visualizing magnetoelectric domains on single crystals of multiferroic hexagonal manganites. Results of several control experiments exclude artifacts or extrinsic origins of the MeFM signal. The parameters are tuned to optimize the signal to noise ratio.

20.
Nat Commun ; 5: 2998, 2014.
Article in English | MEDLINE | ID: mdl-24389675

ABSTRACT

Improper ferroelectricity (trimerization) in the hexagonal manganites RMnO3 leads to a network of coupled structural and magnetic vortices that induce domain wall magnetoelectricity and magnetization (M), neither of which, however, occurs in the bulk. Here we combine first-principles calculations, group-theoretic techniques and microscopic spin models to show how the trimerization not only induces a polarization (P) but also a bulk M and bulk magnetoelectric (ME) effect. This results in the existence of a bulk linear ME vortex structure or a bulk ME coupling such that if P reverses so does M. To measure the predicted ME vortex, we suggest RMnO3 under large magnetic field. We suggest a family of materials, the hexagonal RFeO3 ferrites, also display the predicted phenomena in their ground state.

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