Role of microglia in retinal neurovascular unit of diabetic retinopathy / 国际眼科杂志(Guoji Yanke Zazhi)

Diabetic retinopathy(DR)represents the primary cause of blindness among the global working-age population, and the disruption of the blood-retinal barrier is a crucial factor. Research in recent years has elucidated that DR transcends the scope of a mere microvascular disorder into a complex interplay of retinal glial cells and neurodegeneration microvascular pathology. Neuronal damage may precede vascular endothelial changes in the retinal neurovascular unit(RNVU)in the early stage of DR, and glial cell activation further exacerbates vascular barrier dysfunction. Retinal microglia are immune cells that reside in the retina and are involved in chronic inflammatory responses induced by long-term exposure to high glucose levels. Microglia secrete various inflammatory factors in response to high glucose levels, which can lead to the destruction of the blood-retinal barrier structure, increased neuronal apoptosis, and altered gliosis of Muller cells, thus affecting the retina's homeostatic balance. The RNVU has received increasing attention in recent years as a unitary structural study, and the mechanism of microglia in the RNVU and the progress of the study are reviewed.

Effects of Lactobacillus Rhamnosus GG on Activated Microglia and Tau Phosphorylation in the Hippocampus of Aged Mice Induced by Anesthesia and Surgery / 中山大学学报(医学科学版)

ObjectiveTo investigate the effects of Lactobacillus rhamnosus GG （LGG）on microglia and Tau phosphorylation in the hippocampus of aged mice induced by anesthesia and surgery. MethodsA total of thirty 18-month-old C57BL/6J mice were randomly divided into three groups： control group， anesthesia surgery group， and anesthesia surgery + LGG group （10 mice/group）. The aged mice were oral administered by NS or LGG 109 CFU 150 μL once a day for 20 days. Then anesthesia surgery group and anesthesia surgery +LGG group received anesthesia with isoflurane and exploratory laparotomy. The activation status of microglia in the hippocampus was detected by immunofluorescence staining 12 hours after surgery. IL-6 concentration changes was detected by ELISA. The expression changes of Tau protein phosphorylation site （Tau-pS202/pT205） and total Tau protein was detected by western blot. ResultsThe microglia in the hippocampus of the control group were in a resting state， and the concentration of inflammatory factor IL-6 was （82.08 ± 12.07） pg/mL in control group. Compared to the control group， the anesthesia surgery group showed microglial cell Microglia were activated， the concentration of inflammatory factors IL-6 increased significantly to （123.7±5.72） pg/mL （P=0.000）， and the expression of phosphorylated Tau-pS202/pT205 increased the hippocampus （P=0.002）. Compared to the anesthesia surgery group， the activated microglia were inhibited， the concentration of IL-6 decreased to （96.68±9.59） pg/mL （P=0.008）， and the expression of phosphorylated Tau-pS202/pT205 reduced significantly in the AS+LGG group （P=0.002）. While there were no significant changes in total Tau protein among 3 groups. ConclusionPreoperative administration of probiotic LGG can alleviate the activation of microglia， increased secretion of inflammatory factors， and increased Tau protein phosphorylation levels in the hippocampus of elderly mice caused by anesthesia surgery.

Research progress on phenotype and function of microglia / 中国药理学通报

Microglia are the central nervous system's resident myeloid-derived immune cells, which play a major role in the innate and acquired immunological responses of brain. In the maintenance of brain tissue function under both healthy and pathological conditions, microglia take a protective or damaging role, depending on cell phenotypes and functions. The traditional microglia classification of pro- or anti-inflammatory phenotypes refers to the profile of macrophages, hence the term “brain macrophages:has been drawn. More microglia phenotypes are being discovered as new technologies and research methods are developed, and the newly discovered microglia phenotypes are often disease-, brain region-, and function-specific, providing an important foundation for studying the pathological processes underlying the development of specific diseases and developing appropriate interventions. Here, we provide a retrospective review of recent advances in the study of phenotype and function of microglia, and analyze the microglial cell lineage composition and its heterogeneous function.

Konjac Mannan Oligosaccharides enhanced intestinal barrier function to improve alcoholic nervous injury / 中国药理学通报

Aim Excessive cerebral inflammation caused by chronic alcohol intake is an important risk factor for central nervous system injury. The purpose of this study was to explore the protective effect of konjac mannan oligosaccharide (KMOS) on central nervous system inflammation in alcohol-fed mice and its mechanism. Methods The chronic alcohol fed model of C57BL/6J mice was established using Gao-binge method. And the different doses of KMOS were gavaged every day for 6 weeks. The neuronal damage and microglia activation were evaluated in cerebral cortex and hippocampus. The damage of colon tissue was assessed and serum LPS concentrations were measured. In vitro, Caco-2 cells were stimulated with LPS to establish intestinal mucosal injury model. Results Chronic alcohol intake can cause brain neuron damage in mice, and different doses of KMOS effectively reduced the activation state of microglia, decreased the expression of inflammatory factors caused by the activation of the NLRP3 inflammasome and alleviated neuronal damage in the brain tissue of alcohol-fed mice. The results of colon tissue analysis showed that the use of KMOS effectively reduced the concentration of endotoxin LPS in serum of alcohol-fed mice, alleviated the pathological injury and inflammatory response of colon tissue, and enhanced the expression of Occludin in intestinal tissue. In vitro experiments also showed that KMOS significantly inhibited the inflammatory reaction of Caco-2 cells exposed to alcohol and increased the expression of Occludin protein. Conclusions KMOS treatment effectively inhibited intestinal inflammation caused by alcohol intake, repaired intestinal barrier to prevent the entry of intestinal LPS into brain tissue, decreased the activation of microglia, and then improved brain neuron damage. KMOS had the potential to prevent alcoholic nerve injury.

Research progress of neuronal injury mediated by microglial activation and depression / 中国药理学通报

Depression is a common neurological disorder with high incidence, high recurrence and high disability, but its pathogenesis is unclear. In recent years, the protective and attacking effects of glial cells on neurons have become the frontier of neurological disease research. Neuronal injury caused by abnormal activation of microglia (MG) plays an important role in the pathogenesis of depression. In this paper, through literature retrieval by GeenMedical and CNKI, the relevant pathways and key targets of MG activation in depression are summarized so as to provide a theoretical basis for further clinical research.

Effect of safflower yellow on learning and memory ability of APP/PS1 at different months based on TLR4/NF-KB signaling pathway / 中国药理学通报

Aim To investigate the effect of safflower yellow (SY) on learning and memory ability of APP/ PS1 mice at different disease stages, and to explore the mechanism of SY anti- Alzheimer's disease by using 3-,6- and 9-month-old APP/PS 1 transgenic mice as experimental animal models. Methods Behavioral experiments were conducted to observe the effects of SY on learning and memory of APP/PS1 mice of different months. ELISA was used to detect the effect of SY on the expression of inflammatory factors in cortex of mice of different months. Western blot was used to detect the microglia activation marker protein, and its mechanism of action was further analyzed. Results SY could enhance the learning and memory ability of mice aged 3, 6 and 9 months, reduce the content of IL-6 and increase the content of TGF-β1 in brain tissue, up-regulate the expression levels of arginase-1 (arg-1) and triggering receptor expressed on myeloid cells 2 (tREM2) in brain tissue of mice of different months, and down-regulate the expression levels of inducible nitric oxide synthase (iNOS), Toll-like receptors 4 (tlr4) and nuclear factor-kappa B (nf-KB). Conclusions Compared with 3- and 9-month-old mice, SY is the most effective in improving learning memory in 6-month-old APP/PS1 mice. SY inhibits TLR4/NF-KB pathway activation by inducing TREM2 expression in brain tissue of APP/PS 1 transgenic mice, promotes microglia phenotype shift to anti-inflammatory phenotype, reduces chronic neuroinflammatory response, and improves learning memory in APP/PS1 mice at all months of age.

Toxic effects of permethrin on HMC3 microglia and its associated mechanism / 环境与职业医学

Background Permethrin is a commonly used pyrethroid insecticide and has been found to be potentially neurotoxic. Microglia are innate immune cells in the central nervous system and are involved in the development of a range of neurodegenerative diseases. Objective To observe possible toxic effects of permethrin on human microglia clone 3 (HMC3) in vitro and explore associated mechanism. Methods HMC3 were treated with 0, 10, 25, and 55 μmol·L−1 permethrin for 72 h. Cell cycle and apoptosis were measured using flow cytometry. Cyclin-dependent kinase 1 (CDK1), cyclin-dependent kinase inhibitor 1A (CDKN1A), cyclin B2 (CCNB2), cellular tumor antigen p53 (p53), factor-related apoptosis (FAS), caspase 3 (CASP3), and H2A histone family member X (H2AX) were detected by quantitative real-time PCR (qPCR). The differential genes and enrichment pathways of HMC3 after 0 and 25 μmol·L−1 permethrin treatment was analyzed by RNA sequencing. HMC3 was treated by 0, 10, 25, and 55 μmol· L−1 permethrin for 72 h. The content of nitric oxide (NO) in the supernatant was detected using Griess reagent. The secretion level of interleukin-6 (IL-6) was detected by enzyme linked immunosorbent assay (ELISA). The mRNA expression levels of mitogen-activated protein kinase (MAPK) pathway (including MAPK1, MAPK8, and MAPK14), interleukin-1β (IL-1β), IL-6, and matrix metalloproteinase (MMP) families (including MMP1, MMP2, MMP3, and MMP9) were detected by qPCR. The protein expressions of phosphorylated p38 mitogen-activated protein kinase (p-p38), phosphorylated extracellular signal-regulated kinase (p-ERK), IL-1β, IL-6, and MMP1 were detected by Western blot. Results HMC3 was arrested in G2/M phase after 0, 10, 25, and 55 μmol·L−1 permethrin treatment for 72 h, of which there was a statistically significant difference between the 55 μmol·L−1 permethrin treatment group and the control group (P<0.01), and the mRNA expression of CDKN1A was up-regulated according to the qPCR (P<0.05). There was no statistically significant difference in the proportions of apoptosis between the groups (P＞0.05). The RNA sequencing showed that the differential genes were enriched in the MAPK pathway, and the mRNA expressions of MAPK1, MAPK8, and MAPK14 were up-regulated after the permethrin treatment at 55 μmol·L−1 compared to the control group by qPCR (P<0.05). The Western blot revealed that, compared to the control group, the levels of p-p38 and p-ERK were increased after the 10 μmol·L−1 permetrin treatment (P<0.05), the p-ERK level was increased after the 25 μmol·L−1 permetrin treatment (P<0.05), and the p-p38 level was up-regulated after the 55 μmol·L−1 permetrin treatment (P<0.05). The secretion of NO in the supernatant of HMC3 increased after permetrin treatment compared to the control group (P<0.05), the mRNA and protein expressions and the secretion of IL-6 showed an upward trend, the mRNA and protein expressions of IL-1β were up-regulated (P<0.05), and the mRNA and protein expressions of MMP1 were up-regulated in the 25 and 55 μmol·L−1 permethrin groups (P<0.05). Conclusion Permethrin inhibits HMC3 cell proliferation in vitro, induces cell cycle arrest, activates MAPK pathway, and promotes the expression of inflammatory factors IL-1β and MMP1, which may be one of the mechanism of neurotoxicity induced by permethrin.

Effect of Early Intervention of Yishen Huazhuo Prescription on Learning and Memory of Accelerated Aging SAMP8 Mice and Its Mechanism / 中国实验方剂学杂志

ObjectiveTo investigate the impact of early intervention with Yishen Huazhuo prescription （YHP） on the learning and memory of accelerated aging model mice， as well as its underlying mechanism. MethodForty-eight 3-month-old male SAMP8 mice were randomly assigned into four groups， including the model group， low-dose YHP group， high-dose YHP group， and donepezil group. Additionally， 24 SAMR1 mice of the same age were divided into a control group and a YHP treatment control group， each consisting of 12 mice. The YHP groups received YHP at doses of 6.24 g·kg-1 and 12.48 g·kg-1， while the donepezil group was treated with donepezil at a dose of 0.65 mg·kg-1. The model group and control groups were given physiological saline. The mice were gavaged once daily for a duration of four weeks. Spatial learning and memory abilities of mice were assessed using the Morris water maze test. Immunofluorescence staining was employed to evaluate neuronal density as well as expression levels of M1 microglial （MG） polarization marker inducible nitric oxide synthase （iNOS） and M2 MG polarization marker arginase-1 （Arg-1） in the hippocampus region. Enzyme-linked immunosorbent assay （ELISA） was used to measure serum levels of pro-inflammatory factor interleukin 1β （IL-1β） and anti-inflammatory factor transforming growth factor-β1 （TGF-β1）. Furthermore， Western blot analysis was conducted to determine expressions of amyloid β peptide1-42 （Aβ1-42） along with triggering receptor expressed on myeloid cells 2 （TREM2）/nuclear factor kappa B （NF-κB） signaling pathway-related proteins TREM2， phospho （p）-NF-κB p65， and phospho-inhibitory kappa B kinase β （IKKβ） in the hippocampus. ResultCompared with the control group， the model group exhibited a significantly prolonged escape latency （P<0.01）， a significant reduction in neuron-specific nuclear protein （NeuN） expression in the hippocampus， a significant increase in iNOS expression in MG， and a significant decrease in Arg-1 expression. The serum IL-1β content was significantly increased， while the TGF-β1 content was significantly decreased. Additionally， there was a significant decrease in TREM2 expression in the hippocampus and significant increases in p-NF-κB p65， p-IKKβ， and Aβ1-42 expressions （P<0.05， P<0.01）. However， no significant changes were observed in escape latency， times of crossing the platform， and hippocampal NeuN expression in the YHP treatment control group. Conversely， iNOS expression in MG as well as the hippocampal p-NF-κB p65， p-IKKβ， and Aβ1-42 expressions were significantly decreased. Furthermore， TREM2 expression was significantly increased （P<0.05， P<0.01）. In comparison to the model group， the low-dose YHP group showed a significantly shortened escape latency and an increased number of crossing the platform （P<0.05， P<0.01）. In the high-dose YHP group， the escape latency was significantly shortened （P<0.05）. In the low-dose YHP group， high-dose YHP group， the expression of NeuN in the hippocampus was significantly increased， the expression of iNOS in MG was significantly decreased， and the expression of Arg-l was significantly increased. The serum IL-1β content was significantly decreased， while the TGF-β1 content was significantly increased. Furthermore， the expression of TREM2 in the hippocampus was significantly increased， and the expressions of p-NF-κB p65， p-IKKβ， and Aβ1-42 were significantly decreased （P<0.01）. ConclusionEarly YHP intervention may promote the transformation of hippocampal MG from M1 to M2 by regulating the TREM2/NF-κB signaling pathway， reduce the release of neuroinflammatory factors， protect hippocampal neurons， and reduce the deposition of Aβ1-42， and finally delay the occurrence of learning and memory decline in SAMP8 mice.

Single-Cell Mapping of Brain Myeloid Cell Subsets Reveals Key Transcriptomic Changes Favoring Neuroplasticity after Ischemic Stroke / 神经科学通报·英文版

Interactions between brain-resident and peripheral infiltrated immune cells are thought to contribute to neuroplasticity after cerebral ischemia. However, conventional bulk sequencing makes it challenging to depict this complex immune network. Using single-cell RNA sequencing, we mapped compositional and transcriptional features of peri-infarct immune cells. Microglia were the predominant cell type in the peri-infarct region, displaying a more diverse activation pattern than the typical pro- and anti-inflammatory state, with axon tract-associated microglia (ATMs) being associated with neuronal regeneration. Trajectory inference suggested that infiltrated monocyte-derived macrophages (MDMs) exhibited a gradual fate trajectory transition to activated MDMs. Inter-cellular crosstalk between MDMs and microglia orchestrated anti-inflammatory and repair-promoting microglia phenotypes and promoted post-stroke neurogenesis, with SOX2 and related Akt/CREB signaling as the underlying mechanisms. This description of the brain's immune landscape and its relationship with neurogenesis provides new insight into promoting neural repair by regulating neuroinflammatory responses.

Wenyang Jieyu Prescription Regulates Hippocampal Neural Plasticity in Depressed Mice via NLRP3/Caspase-1/IL-1β Pathway / 中国实验方剂学杂志

ObjectiveTo explore the effects of Wenyang Jieyu prescription （WJP） on neuroinflammation and synaptic plasticity in the mouse model of depression induced by maternal separation combined with restraint stress. MethodThe mice on postnatal day 0 （PD0） were randomized into a control group and a modeling group. Maternal separation combined with restraint stress was employed to establish the mouse model of depression. After the removal of female mice， the modeled mice were randomized into model， Wenyang prescription （5.85 g·kg-1）， Jieyu prescription （12.03 g·kg-1）， WJP （16.71 g·kg-1）， and fluoxetine （2.6 mg·kg-1） groups on the weaning day （PD21）， with 15 mice in each group. The mice were administrated with corresponding drugs mixed with the diet from PD21 to PD111. The sucrose preference test， open field test， O-maze test， and novel object recognition test were then carried out to evaluate the depression state， memory， and learning ability of the mice. Immunohistochemistry （IHC） was employed to observe the ionized calcium-binding adapter molecule-1 （Iba-1） in hippocampal microglia. High performance liquid chromatography （HPLC） was employed to measure the content of noradrenaline （NE） and epinephrine （E） in the hippocampus. Enzyme-linked immunosorbent assay （ELISA） was employed to determine the content of interleukin （IL）-18 and IL-1β in the hippocampus. Western blot was employed to determine the protein levels of NOD-like receptor protein 3 （NLRP3）， apoptosis-associated speck-like protein containing a CARD （ASC）， cysteine aspartate-specific protease-1 （Caspase-1）， IL-1β， synaptophysin （Syn）， and postsynaptic density 95 （PSD95）. ResultCompared with control group， the model group showed decreased sucrose preference rate， time spent in central zone within 5 min， total movement distance， time spent in the open arm， and cognition index （P<0.05， P<0.01）. The microglia in the model group presented amoeba-like appearance， the Iba1 increased. Moreover， the model group showed decreased content of NE and E （P<0.01）， elevated levels of IL-1β and IL-18 （P<0.01）， down-regulated protein levels of PSD95 and Syn （P<0.05， P<0.01）， and up-regulated protein levels of NLRP3， ASC， Caspase-1， and IL-1β （P<0.05， P<0.01）. Compared with model group， WJP and fluoxetine increased the sucrose preference rate， time spent in central zone within 5 min， total movement distance， time spent in the open arm， and cognition index （P<0.05， P<0.01）. They recovered the microglia and the Iba1 decreased. Moreover， the drugs increased the content of NE and E （P<0.05， P<0.01）， lowered the levels of IL-1β and IL-18 （P<0.01）， up-regulated the protein levels of PSD95 and Syn （P<0.01）， down-regulated the protein levels of NLRP3， ASC， Caspase-1， and IL-1β （P<0.05， P<0.01）. ConclusionWJP can treat the depressive behavior induced by maternal separation combined with restraint stress in mice， with the performance outperforming Wenyang prescription and Jieyu prescription. It may alleviate the neuroinflammation induced by microglia and improve the synaptic plasticity by regulating the NLRP3 pathway and increasing neurotransmitters in the hippocampus.

Modified Xiaoyaosan Alleviates Depression-like Behaviors by Regulating Activation of Hippocampal Microglia Cells in Rat Model of Juvenile Depression / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of Baihuan Xiaoyao Decoction （Xiaoyaosan added with Lilii Bulbus and Albiziae Cortex） in alleviating depression-like behaviors of juvenile rats by regulating the polarization of microglia. MethodSixty juvenile SD rats were randomized into normal control， model， fluoxetine， and low-， medium-， and high-dose （5.36， 10.71， 21.42 g·kg-1， respectively） Baihuan Xiaoyao decoction groups. The rat model of juvenile depression was established by chronic unpredictable mild stress （CUMS）. The sucrose preference test （SPT） was carried out to examine the sucrose preference of rats. Forced swimming test （FST） was carried out to measure the immobility time of rats. The open field test （OFT） was conducted to measure the total distance， the central distance， the number of horizontal crossings， and the frequency of rearing. Morris water maze （MWM） was used to measure the escape latency and the number of crossing the platform. The immunofluorescence assay was employed to detect the expression of inducible nitric oxide synthase （iNOS， the polarization marker of M1 microglia） and CD206 （the polarization marker of M2 microglia）. Real-time polymerase chain reaction was employed to determine the mRNA levels of iNOS， CD206， pro-inflammatory cytokines ［tumor necrosis factor （TNF）-α， interleukin （IL）-1β， and IL-6］ and anti-inflammatory cytokines （IL-4 and IL-10） in the hippocampus. Western blotting was employed to determine the protein levels of iNOS and CD206 in the hippocampus. The levels of IL-4 and IL-6 in the hippocampus were detected by enzyme-linked immunosorbent assay. ResultCompared with the normal control group， the model rats showed a reduction in sucrose preference （P<0.05）， an increase in immobility time （P<0.05）， decreased motor and exploratory behaviors （P<0.05）， and weakened learning and spatial memory （P<0.05）. In addition， the model rats showed up-regulated mRNA and protein levels of iNOS and mRNA levels of IL-1β， IL-6， and TNF-α （P<0.05）. Compared with the model group， Baihuan Xiaoyao decoction increased the sucrose preference value （P<0.05）， shortened the immobility time （P<0.01）， increased the motor and exploratory behaviors （P<0.05）， and improved the learning and spatial memory （P<0.01）. Furthermore， the decoction down-regulated the positive expression and protein level of iNOS， lowered the levels of TNF-α， IL-1β， and IL-6 （P<0.01）， promoted the positive expression of CD206， and elevated the levels of IL-4 and IL-10 （P<0.01） in the hippocampus of the high dose group. Moreover， the high-dose Baihuan Xiaoyao decoction group had higher sucrose preference value （P<0.01）， shorter immobility time （P<0.01）， longer central distance （P<0.01）， stronger learning and spatial memory （P<0.01）， higher positive expression and protein level of iNOS （P<0.01）， lower levels of TNF-α， IL-1β， and IL-6 （P<0.05， P<0.01）， lower positive expression and mRNA level of iNOS （P<0.05）， and higher levels of IL-4 and IL-10 （P<0.05， P<0.01） than the fluoxetine group. ConclusionBaihuan Xiaoyao decoction can improve the depression-like behavior of juvenile rats by inhibiting the M1 polarization and promoting the M2 polarization of microglia in the hippocampus.

Research progress on the mechanisms of microglia in retinal angiogenesis / 国际眼科杂志(Guoji Yanke Zazhi)

As resident immune cells of the retina, retinal microglia constantly monitor the changes of their surroundings and maintain homeostasis through signal transduction with other retinal cells. Retinal microglia play a crucial role not only in the development and physiological processes of the retinal vascular system, but also in pathological neovascularization. In certain retinopathies, activated microglia can stimulate abnormal angiogenesis through neurovascular coupling, leading to irreversible damage. However, the exact mechanisms underlying this process are still unclear. In this review, a brief overview of the relationship between microglia and retinal neovascularization was provided, and the involved cellular and molecular signaling mechanisms were reviewed, aiming to offer new and effective strategies for the prevention and treatment of retinal neovascularization diseases.

Chaihu Longgu Mulitang Relieves Generalized Anxiety Disorder in Rats via p38 MAPK/NF-κB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo study whether Chaihu Longgu Mulitang can inhibit hypothalamic inflammation， mitigate anxiety-like behavior， and alleviate anxiety symptoms by regulating the p38 mitogen-activated protein kinase/nuclear factor-κB （p38 MAPK/NF-κB） signaling pathway in the rat model of generalized anxiety disorder （GAD）. MethodTwelve out of 74 Wistar rats were randomly selected as the blank group， and the remaining rats were subjected to chronic restraint stress for the modeling of GAD. The open field test （OFT） and elevated Porteus maze test （PMT） were conducted 14 days after modeling to detect the anxiety-like behaviors. Sixty successfully modeled rats were selected and randomized into model， low-， medium-， and high-dose （6， 12， and 24 g·kg-1， respectively） Chaihu Longgu Mulitang， and diazepam （1 mg·kg-1） groups （n=12） and administrated with corresponding drugs for 14 consecutive days. OFT and PMT were then carried out to examine the anxiety-like behaviors of the rats. The levels of tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， and interleukin-1β （IL-1β） in the hypothalamus and serum of rats were determined by the enzyme-linked immunosorbent assay （ELISA）. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）was conducted to determine the mRNA levels of p38 MAPK， NF-κB p65， nuclear factor κB inhibitor α （IκBα）， and ionized calcium binding adaptor molecule 1 （Iba-1）. The protein levels of p38 MAPK， phosphorylated （p）-p38 MAPK， NF-κB p65， p-NF-κB p65， and IκBα in the hypothalamus of rats were determined by Western blot. The expression of Iba-1 in the hypothalamic microglia was detected by immunofluorescence assay. ResultCompared with the blank group， the model group had decreased body weight， scattered dark yellow fur， increased irritability， and preference to hibernation in the corner. In addition， the modeled rats showed increased edge movement distance and time in OFT （P<0.01） and decreased movement distance and time and the number of entries in the open arm in PMT （P<0.01）. The modeling increased the fluorescence intensity of Iba-1 in paraventricular nucleus of hypothalamus （P<0.01）， elevated the levels of IL-1β， IL-6， and TNF-α in the serum and hypothalamus （P<0.01）， up-regulated the protein and mRNA levels of p38 MAPK， NF-κB p65， p-p38 MAPK， p-NF-κB p65， and Iba-1 （P<0.05， P<0.01）， and down-regulated the protein and mRNA levels of IκBα （P<0.01） in the hypothalamus. Compared with the model group， medium- and high-dose Chaihu Longgu Mulitang and diazepam increased the body weight， improved the fur and behaviors， decreased the edge movement distance and time in OFT （P<0.05， P<0.01）， and increased the movement distance and time in the open arm in PMT （P<0.05， P<0.01）. Furthermore， they decreased the fluorescence intensity of Iba-1 in hypothalamic microglia （P<0.05， P<0.01）， lowered the levels of IL-1β， IL-6， and TNF-α in the serum and hypothalamic tissue （P<0.05， P<0.01）， down-regulated the mRNA and protein levels of p38 MAPK， NF-κB p65， p-p38 MAPK， p-NF-κB p65， and Iba-1 （P<0.05， P<0.01）， and up-regulated the mRNA and protein levels of IκBα （P<0.05， P<0.01） in the hypothalamus. ConclusionChaihu Longgu Mulitang can mitigate anxiety-like behaviors and relieve anxiety in GAD rats by inhibiting the p38 MAPK/NF-κB signaling pathway and reducing the activation of microglia and the levels of pro-inflammatory cytokines in the hypothalamus.

Repair effect of ephedrine on lipopolysaccharide-induced microglia function injury and its mechanism / 中国药房

OBJECTIVE To study the repair effect of ephedrine on lipopolysaccharide （LPS）-induced microglia function injury and its mechanism. METHODS Human microglia cells （HMC3） were used as research objects to investigate the effects of different concentrations of ephedrine （75， 150， 300， 600 μg/mL） on the viability and apoptosis of HMC3 cells. HMC3 cells were divided into control group （without drug intervention）， LPS group （1 μg/mL）， ephedrine group （1 μg/mL LPS+300 μg/mL ephedrine）， BAY11-7082 group [1 μg/mL LPS+5 μmol/L nuclear factor-κB （NF-κB） pathway inhibitor BAY11-7082]， inhibitor group （1 μg/mL LPS+300 μg/mL ephedrine+5 μmol/L BAY11-7082） and activator group （1 μg/mL LPS+300 μg/mL ephedrine+1 μmol/L NF-κB pathway activator Prostratin）. After 24 hours of drug treatment， cell migration， the levels of soluble interleukin-6（sIL-6）， interleukin-10（IL-10）， superoxide dismutase（SOD）and malondialdehyde（MDA）， and the expressions of NF-κB pathway-related proteins were all detected. RESULTS The viability of HMC3 cells could be increased significantly by 300 μg/mL ephedrine， while the apoptotic rate was decreased significantly （P＜0.05）. Compared with the control group， the number of migrating cells was increased significantly in the LPS group； the levels of sIL-6 and MDA， the phosphorylation of NF-κB protein were increased significantly， while the levels of IL-10 and SOD were decreased significantly （P＜0.05）. Compared with the LPS group， the above indexes were reversed significantly in the ephedrine group and BAY11-7082 group （P＜0.05）. Compared with the ephedrine group， the number of migrating cells was decreased significantly in the inhibitor group； the levels of sIL-6 and MDA， the phosphorylation of NF-κB protein were decreased significantly， while the levels of IL-10 and SOD were increased significantly （P＜0.05）. The above indexes were reversed significantly in the activator group （P＜0.05）can repair cell injury by inhibiting LPS induced apoptosis， migration， inflammation and oxidant stress of HMC3 cells， the mechanism of which may be associated with inhibiting the activity of the NF-κB signaling pathway.

Mechanism of Traditional Chinese Medicine in Treatment of Neurodegenerative Diseases by Regulating Polarization Balance of Microglia： A Review / 中国实验方剂学杂志

Neuroinflammation is a common pathological feature of neurodegenerative diseases （NDs）. Microglia （MG）， a resident macrophage in the brain with a unique developmental origin， is the core driver of neuroinflammation. It can participate in the occurrence and development of NDs through different polarization states and play a key role in regulating neurogenesis and synapse shaping and maintaining homeostasis. MG can be divided into M1 pro-inflammatory phenotype and M2 anti-inflammatory phenotype according to its function. The inflammatory mediators released by the M1 phenotype can lead to nerve degeneration and myelin sheath damage， while the activation of the M2 phenotype is required to inhibit the inflammatory response and promote tissue repair. With the advantages of multi-pathway， multi-target， and bidirectional regulation， traditional Chinese medicine can regulate the polarization balance of MG and has dual effects on NDs such as Alzheimer's disease， Parkinson's disease， and multiple sclerosis. The active components of traditional Chinese medicine and its compound can inhibit the activation of MG by regulating phosphatidylinositol-3-kinases/protein kinase B（PI3K/Akt）， NOD-like receptor thermal protein domain associated protein 3（NLRP3）， signal transducer and activator of transcription factor1（STAT1）， nuclear transcription factor kappa B（NF-κB）， and other pathways， promote the polarization of M1 phenotype to M2 phenotype， reduce the expression of interleukin（IL）-6， tumor necrosis factor-α（TNF-α）， and other pro-inflammatory factors， and increase the secretion of IL-10， arginase-1（Arg-1）， and other anti-inflammatory factors. It can also reduce β-amyloid deposition and tau protein expression in Alzheimer's disease， alleviate dopaminergic neuronal damage in Parkinson's disease， and relieve demyelination， inflammatory cell infiltration， and related clinical symptoms of multiple sclerosis. The bidirectional regulation of the M1/M2 polarization balance of MG by traditional Chinese medicine is a potential strategy for the treatment of NDs. This paper focused on the targets of the regulation of MG polarization balance by traditional Chinese medicine monomer and its compound in the treatment of NDs， so as to further study and summarize the existing research results and provide ideas and basis for the future treatment of NDs.

La alteración hipotalámica en la obesidad: neuroinflamación y disfunción metabólica / The hypotalamic disturbances during obesity: neuroinflammation and metabolic dysfunction

Resumen La obesidad es considerada actualmente como un problema de salud pública global y se caracteriza por la hipertrofia e hiperplasia del tejido adiposo debido a la ingesta hipercalórica y la falta de actividad física, disfunción metabólica, inflamación sistémica crónica de bajo grado y gradualmente neuroinflamación hipotalámica. El tejido adiposo actúa como un órgano endocrino secretando adipocinas y citocinas que actúan como reguladores del metabolismo. Sin embargo, la presencia de niveles elevados de ácidos grasos libres y de moléculas inflamatorias derivadas de los adipocitos, pueden alterar la respuesta inmunitaria sistémica, generando inflamación crónica, comprometiendo la integridad de la barrera hematoencefálica y estimulando la respuesta de la glía, especialmente en regiones específicas del hipotálamo, centro de regulación de la homeostasis energética. Las células gliales hipotalámicas son importantes en la transmisión de señales inflamatorias relacionadas con la dieta, pueden modular la actividad neuronal, responder a las señales inmunológicas periféricas e iniciar una respuesta inflamatoria local y gliosis. Esta revisión se enfoca en la descripción general de la disfunción metabólica asociada a la obesidad y su participación en la alteración de la regulación hipotalámica, provocando neuroinflamación y modificaciones en la conducta alimentaria.

Abstract Nowadays, obesity is considered a worldwide rising health problem and is characterized by adipose tissue hypertrophy and hyperplasia due to hypercaloric intake and lack of physical activity, promoting the development of metabolic dysfunction, low-grade systemic chronic inflammation, and gradually hypothalamic neuroinflammation. Adipose tissue acts as an endocrine organ secreting adipokines and cytokines around peripheral organs, functioning as a master metabolism regulator. However, high levels of adipocyte-derived free fatty acids and inflammatory molecules promote impairments in systemic immune response, generate chronic inflammation, disrupt the blood-brain barrier, and stimulate glia, specifically in some hypothalamic regions, the master regulators of energetic homeostasis. Hypothalamic glial cells are essential in diet-related inflammatory signals transmission and can modulate neuronal activity, also respond to peripheral inflammatory signals and begin local inflammatory response and gliosis. This review aims to analyze obesity-related metabolic dysfunction and how it participates in the hypothalamic regulation impairments due to neuroinflammation and impairment in food intake behavior.

In vitro immunogenic profile of recombinant SARS-CoV2 S1-RBD peptide in murine macrophage and microglial cells

BACKGROUND The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants can infect common mice inducing significant pathological lung lesions and inflammatory responses. This substantially mimics coronavirus disease 19 (COVID-19) infection and pathogenesis in humans. OBJECTIVES To characterise the effects of recombinant SARS-CoV-2 S1 receptor-binding domain (RBD) peptide in murine macrophage and microglial cells' immune activation compared with classical PAMPs in vitro. METHODS Murine RAW 264.7 macrophages and BV2 microglial cells were exposed to increasing concentrations of the RBD peptide (0.01, 0.05, and 0.1 µg/mL), Lipopolysaccharide (LPS) and Poly(I:C) and evaluated after two and 24 h for significant markers of macrophage activation. We determined the effects of RBD peptide on cell viability, cleaved caspase 3 expressions, and nuclear morphometry analysis. FINDINGS In RAW cells, RBD peptide was cytotoxic, but not for BV2 cells. RAW cells presented increased arginase activity and IL-10 production; however, BV2 cells expressed iNOS and IL-6 after RBD peptide exposure. In addition, RAW cells increased cleaved-caspase-3, apoptosis, and mitotic catastrophe after RBD peptide stimulation but not BV2 cells. CONCLUSION RBD peptide exposure has different effects depending on the cell line, exposure time, and concentration. This study brings new evidence about the immunogenic profile of RBD in macrophage and microglial cells, advancing the understanding of SARS-Cov2 immuno- and neuropathology.

Reaserch progress of microglial phagocytosis in ischemic stroke / 中国药科大学学报

@#Ischemic stroke is a major disease affecting human health, and its pathological mechanism has not been fully elucidated. Microglia are important immune cells in the central nervous system, and participate in the pathological process of ischemic stroke.Following an ischemic stroke, a surge in activated microglia occurs, migrating and congregating within the afflicted regions.These microglia engulf deceased cells or fragments, releasing inflammatory or nutritive factors, thereby participating in the pathogenesis of ischemic stroke.The phagocytosis of microglia plays an important role in cerebral ischemic injury and rehabilitation. This article summarizes the molecular mechanism of microglial phagocytosis and reviews the research progress of microglial phagocytosis in ischemic stroke, and discusses the diversity and complexity of microglial phagocytosis in cerebral ischemic injury and rehabilitation, so as to provide new ideas for the treatment and drug development of ischemic stroke.

Acetylcorynoline inhibits microglia activation by regulating EGFR/MAPK signaling to promote functional recovery of injured mouse spinal cord / 南方医科大学学报

OBJECTIVE@#To investigate the effect of acetylcorynoline (Ace) for promoting functional recovery of injured spinal cord in rats and explore the underlying mechanism.@*METHODS@#Rat models of spinal cord injury (SCI) were treated with intraperitoneal injection of different concentrations of Ace, with the sham-operated rats as the control group. After the treatment, the changes in motor function of the rats and the area of spinal cord injury were assessed with BBB score and HE staining, and the changes in pro-inflammatory cytokine levels and microglial activation were determined using PCR, ELISA and immunofluorescence staining. In a lipopolysaccharide (LPS)-treated BV2 cell model, the effects of different concentrations of Ace or DMSO on microglial activation and inflammatory cytokine production were observed. Network pharmacology analysis was performed to predict the target protein and signaling mechanism that mediated the inhibitory effect of Ace on microglia activation, and AutoDock software was used for molecular docking between Ace and the target protein. A signaling pathway blocker (Osimertinib) was used to verify the signaling mechanism in rat models of SCI and LPS-treated BV2 cell model.@*RESULTS@#In rat models of SCI, Ace treatment significantly increased the BBB score, reduced the area of spinal cord injury, and lowered the number of activated microglia cells and the levels of pro-inflammatory cytokines (P < 0.05). The cell experiments showed that Ace treatment significantly lower the level of cell activation and the production of inflammatory cytokines in LPS-treated BV2 cells (P < 0.05). Network pharmacology analysis suggested that EGFR was the main target of Ace, and they bound to each other via hydrogen bonds as shown by molecular docking. Western blotting confirmed that Ace inhibited the activation of the EGFR/MAPK signaling pathway in injured mouse spinal cord tissue and in LPS-treated BV2 cells, and its inhibitory effect was comparable to that of Osimertinib.@*CONCLUSION@#In rat models of SCI, treatment with Ace can inhibit microglia-mediated inflammatory response by regulating the EGFR/MAPK pathway, thus promoting tissue repair and motor function recovery.

TDZD-8 alleviates oxaliplatin induced neuropathic pain / 中国药理学通报

Aim To explore the effect of GSK-3β (glycogen synthase kinase-3 beta) inhibitor TDZD-8 on the neuropathic pain induced by side effects of chemotherapeutic drug oxaliplatin and the underlying mechanism. Methods The rat model of oxaliplatin-induced neuropathic pain was established by intraperitoneal injection of oxaliplatin for five consecutive days; the anti-nociception effect was detected by intrathecal injection of TDZD-8. The spontaneous flinches and mechanical pain threshold were used to detect the changes of pain behavior of rats; immunofluorescence and Western blot analysis were used to detect the changes of spinal inflammation and protein levels of rats. Results Intrathecally injection of TDZD-8 significantly alleviated oxaliplatin induced hyperalgesia in rats. TDZD-8 injection obviously inhibited the activation spinal microglia and the inflammatory reaction. TDZD-8 administration significantly inhibited GSK-3β activation. Conclusion TDZD-8 blocks GSK-3β activation, decreases NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) inflammasome mediated spinal inflammation and alleviates neuropathic pain.