Role of histone deacetylases and their inhibitors in neurological diseases.

Histone deacetylases (HDACs) are zinc-dependent deacetylases that remove acetyl groups from lysine residues of histones or form protein complexes with other proteins for transcriptional repression, changing chromatin structure tightness, and inhibiting gene expression. Recent in vivo and in vitro studies have amply demonstrated the critical role of HDACs in the cell biology of the nervous system during both physiological and pathological processes and have provided new insights into the conduct of research on neurological disease targets. In addition, in vitro and in vivo studies on HDAC inhibitors show promise for the treatment of various diseases. This review summarizes the regulatory mechanisms of HDAC and the important role of its downstream targets in nervous system diseases, and summarizes the therapeutic mechanisms and efficacy of HDAC inhibitors in various nervous system diseases. Additionally, the current pharmacological situation, problems, and developmental prospects of HDAC inhibitors are described. A better understanding of the pathogenic mechanisms of HDACs in the nervous system may reveal new targets for therapeutic interventions in diseases and help to relieve healthcare pressure through preventive measures.

Development of erythrina-based PARP-1/FTase dual-target inhibitors against lung cancer epithelial-mesenchymal transition (EMT) in vivo and in vitro.

A novel series of erythrina derivatives as PARP-1/FTase inhibitors were synthesized, and evaluated for their biological activities. Compound T9 had excellent inhibitory effects on cell viability (A549: IC50 = 1.74 µM; A549/5-Fu: IC50 = 1.03 µM) and in vitro enzyme activities (PARP-1: IC50 = 0.40 µM; FTase: IC50 = 0.067 µM). Molecular docking and point mutation assays demonstrated the interaction of compound T9 with key amino acid residues. The compound T9 exhibited potent anti-proliferation and anti-migration capabilities against A549 and A549/5-Fu cells. PCR array and western blot results showed that compound T9 could effectively inhibit EMT-related proteins in A549 and A549/5-Fu cells, thereby inhibiting the development of lung cancer. Importantly, compound T9 could significantly inhibit tumor growth in the A549 xenograft tumor model (TGI = 65.3 %). In conclusion, this study was the first presentation of the concept of dual-target inhibitors of the PARP-1/FTase enzymes. It also provides the basis for further research and development of novel PARP-1/FTase inhibitors.

Structural Engineering of BiVO4 /CoFe MOF Heterostructures Boosting Charge Transfer for Efficient Photoelectrochemical Water Splitting.

Boosting charge separation and transfer of photoanodes is crucial for providing high viability of photoelectrochemical hydrogen (H2 ) generation. Here, a structural engineering strategy is designed and synthesized for uniformly coating an ultrathin CoFe bimetal-organic framework (CoFe MOF) layer over a BiVO4 photoanode for boosted charge separation and transfer. The photocurrent density of the optimized BiVO4 /CoFe MOF(NA) photoanode reaches a value of 3.92 mA cm-2 at 1.23 V versus reversible hydrogen electrode (RHE), up to 6.03 times that of pristine BiVO4 , due to the greatly increased efficiency of charge transfer and separation. In addition, this photoanode records one onset potential that is considerably shifted negatively when compared to BiVO4 . Transient absorption spectroscopy reveals that the CoFe MOF(NA) prolongs charge recombination lifetime by blocking the hole-transfer pathway from the BiVO4 to its surface trap states. This work sheds light on boosting charge separation and transfer through structural engineering to enhance the photocurrent of photoanodes for solar H2 production.

Elevated serum anti-Saccharomyces cerevisiae antibody accompanied by gut mycobiota dysbiosis as a biomarker of diagnosis in patients with de novo Parkinson disease.

BACKGROUND AND PURPOSE: Intestinal inflammation and gut microbiota dysbiosis contribute to Parkinson disease (PD) pathogenesis, and growing evidence suggests associations between inflammatory bowel diseases (IBD) and PD. Considered as markers of chronic gastrointestinal inflammation, elevated serum anti-Saccharomyces cerevisiae antibody (ASCA) levels, against certain gut fungal components, are related to IBD, but their effect on PD is yet to be investigated. METHODS: Serum ASCA IgG and IgA levels were measured using an enzyme-linked immunosorbent assay, and the gut mycobiota communities were investigated using ITS2 sequencing and analyzed using the Qiime pipeline. RESULTS: The study included 393 subjects (148 healthy controls [HCs], 140 with PD, and 105 with essential tremor [ET]). Both serum ASCA IgG and IgA levels were significantly higher in the PD group than in the ET and HC groups. Combining serum ASCA levels and the occurrence of constipation could discriminate patients with PD from controls (area under the curve [AUC] = 0.81, 95% confidence interval [CI] = 0.76-0.86) and from patients with ET (AUC = 0.85, 95% CI = 0.79-0.89). Furthermore, the composition of the gut fungal community differed between the PD and HC groups. The relative abundances of Saccharomyces cerevisiae, Aspergillus, Candida solani, Aspergillus flavus, ASV601_Fungi, ASV866_Fungi, and ASV755_Fungi were significantly higher in the PD group, and enriched Malassezia restricta was found in the HC group. CONCLUSIONS: Our study identified elevated serum ASCA levels and enriched gut Saccharomyces cerevisiae in de novo PD.

Chronic colitis exacerbates NLRP3-dependent neuroinflammation and cognitive impairment in middle-aged brain.

BACKGROUND: Neuroinflammation is a major driver of age-related brain degeneration and concomitant functional impairment. In patients with Alzheimer's disease, the most common form of age-related dementia, factors that enhance neuroinflammation may exacerbate disease progression, in part by impairing the glymphatic system responsible for clearance of pathogenic beta-amyloid. Inflammatory bowel diseases (IBDs) induce neuroinflammation and exacerbate cognitive impairment in the elderly. The NACHT-LRR and pyrin (PYD) domain-containing protein 3 (NLRP3) inflammasome has been implicated in neuroinflammation. Therefore, we examined if the NLRP3 inflammasome contributes to glymphatic dysfunction and cognitive impairment in an aging mouse model of IBD. METHODS: Sixteen-month-old C57BL/6J and NLRP3 knockout (KO) mice received 1% wt/vol dextran sodium sulfate (DSS) in drinking water to model IBD. Colitis induction was confirmed by histopathology. Exploratory behavior was examined in the open field, associative memory by the novel-object recognition and Morris water maze tests, glymphatic clearance by in vivo two-photon imaging, and neuroinflammation by immunofluorescence and western blotting detection of inflammatory markers. RESULTS: Administration of DSS induced colitis, impaired spatial and recognition memory, activated microglia, and increased A1-like astrocyte numbers. In addition, DSS treatment impaired glymphatic clearance, aggravated amyloid plaque accumulation, and induced neuronal loss in the cortex and hippocampus. These neurodegenerative responses were associated with increased NLRP3 inflammasome expression and accumulation of gut-derived T lymphocytes along meningeal lymphatic vessels. Conversely, NLRP3 depletion protected against cognitive dysfunction, neuroinflammation, and neurological damage induced by DSS. CONCLUSIONS: Colitis can exacerbate age-related neuropathology, while suppression of NLRP3 inflammasome activity may protect against these deleterious effects of colitis.

Coordination Polymer Derived Porous Carbon Activated in Situ by the ZnCl2 Dot: Capacitances Greatly Enhanced by Redox-Activity Additives in Electrolytes.

Herein, a 1D zinc coordination polymer [Zn(bibp)Cl2]∞ (CP-2-ZX) was assembled from the reaction of 4,4'-bis(imidazol-1-yl)-biphenyl (bibp) with ZnCl2. Through a calcination-thermolysis strategy, sponge-like highly porous carbon AC-Zn-CP was prepared by employing the coralloid sample of CP-2-ZX as the precursor. For comparisons, a series of activated carbon (AC-n) was obtained by the similar heating process on the mixture of bibp with ZnCl2 at different mass ratios. The results illustrate that the atomically dispersed ZnCl2 dot in the 1D chain of CP-2-ZX has an in situ activation effect on the generation of AC-Zn-CP, which can greatly promote the porosity and achieve high-efficiency utilization of ZnCl2. Therefore, the atomically dispersed activating agent provides a new method for environmentally friendly production of porous carbon materials. Significantly, the AC-Zn-CP electrode displays specific capacitance of 215 F g-1 in 3 M KOH solution, which will be largely promoted to 1419 F g-1 in the redox active electrolyte of K3[Fe(CN)6]/KOH. AC-Zn-CP also shows remarkable cycling stability (the capacity retention is 89.0% after 5000 cycles). Moreover, the fabricated symmetric supercapacitor owns a high energy density of 34.8 Wh kg-1 at 785.5 W kg-1. So, the AC-Zn-CP∩K3[Fe(CN)6] system has wide application prospects in supercapacitors.

Fabrication of Metal Nanoparticle Composites by Slow Chemical Reduction of Metal-Organic Frameworks.

Constructing metal nanoparticle (MNP) composites from metal-organic framework (MOF) precursors has attracted extensive attention as the MOF precursors provide an excellent porous matrix for the generation of MNP composites, which enables the direct fabrication of well-dispersed MNP composites. In this work, a novel strategy is proposed to fabricate MNP composites by slow chemical reduction (SCR) of MOF precursors at room temperature. The reduction process is skillfully slowed via using ethanol as the solvent, and the formation of MNP composites is then realized by the SCR process. Briefly, BH4- slowly diffuses into an MOF precursor and in situ reduces metal ions to well-dispersed nanoscale MNP composites. Meanwhile, this SCR process breaks the coordination bonds from MOF precursors, leading to the generation of porous structures for the resulting composites. Interestingly, the composites inherit the morphology of MOF precursors well. Besides, this SCR strategy allows construction of MNP composites from different types of MOF precursors. The resulting Cu@HK-3 composites possess well-dispersed nanoscale Cu NPs and a porous architecture, which exhibit superior catalytic performance and stability in the Ullmann coupling reaction. This strategy provides a feasible, convenient, and energy-saving route to prepare MNP composites from MOF precursors with customizable morphology and well-dispersed MNPs.

Tojapride prevents CaSR-mediated NLRP3 inflammasome activation in oesophageal epithelium irritated by acidic bile salts.

Impairment of the oesophageal epithelium in patients with reflux oesophagitis (RE) is a cytokine-mediated injury rather than a chemical burn. The present study was conducted to explore CaSR/NLRP3 inflammasome pathway activation and cytokines IL-1ß and IL-18 release in oesophageal epithelia injured by refluxates and the effects of Tojapride on that signal regulation. Using a modified RE rat model with Tojapride administration and Tojapride-pretreated SV40-immortalized human oesophageal epithelial cells (HET-1A) exposed to acidic bile salts pretreated with Tojapride, we evaluated the therapeutic effects of Tojapride on oesophageal epithelial barrier function, the expression of CaSR/NLRP3 inflammasome pathway-related proteins and the release of downstream cytokines in response to acidic bile salt irritation. In vivo, Tojapride treatment ameliorated the general condition and pathological lesions of the oesophageal epithelium in modified RE rats. In addition, Tojapride effectively blocked the CaSR-mediated NLRP3 inflammasome activation in modified RE rats. In vitro, Tojapride treatment can reverse the harmful effect of acidic bile salts, which reduced transepithelial electrical resistance (TEER), up-regulated the CaSR-mediated NLRP3 inflammasome pathway and increased caspase-1 activity, LDH release and cytokines secretion. Taken together, these data show that Tojapride can prevent CaSR-mediated NLRP3 inflammasome activation and alleviate oesophageal epithelial injury induced by acidic bile salt exposure.

1/2SH: A Simple, Accurate, and Reliable Method of Calculating the Hematoma Volume of Spontaneous Intracerebral Hemorrhage.

Background and Purpose- 1/2ABC has been used widely for assessing the volume of intracerebral hematoma. However, it is only suitable for calculating regular and small volume hematomas. Therefore, we re-explored the formula of hematoma volume to find a method that can calculate hematoma volumes accurately, reliably, and quickly. Methods- Computed tomography imaging data of 257 patients with intracerebral hemorrhage were collected. Hematoma volumes were estimated using 3-dimensional Slicer and 7 formulas (π/6ABC, 1/2ABC, 1/3ABC, 2/3SH, 1/2SH, π/6SH, and 2.5/6ABC). Taking the hematoma volumes measured by 3-dimensional Slicer as the reference standard, the accuracy and reliability of the 7 formulas were evaluated. Furthermore, the time needed to calculate hematoma volumes by the 1/2SH method was noted for further analysis. Results- (1) The accuracy of the 7 formulas based on the error analysis from the highest to the lowest was: π/6SH, 1/2SH, 2.5/6ABC, 1/3ABC, 1/2ABC, and π/6ABC or 2/3SH. According to concordance analysis and receiver operating characteristic curve analysis, the results from the highest to lowest were as follows: 1/2SH, π/6SH, 2.5/6ABC, 1/3ABC, 1/2ABC, 2/3SH, and π/6ABC. After categorizing cases according to size, shape, and location of hematoma, the results were almost the same as the results for overall accuracy evaluation in any subgroup. (2) Intraclass correlation coefficient (ICC) of 1/2SH in intra and inter-researcher were 0.998 and 0.989, respectively. For the formula π/6SH, intraclass correlation coefficient was the same as that of 1/2ABC. Kappa values of 1/2SH for intra- and inter-observer were 0.992 and 0.913, respectively. For π/6SH, kappa values of within- and between-reader were 0.984 and 0.904, respectively. (3) The average time taken to calculate hematoma volumes by 1/2SH was 74 seconds. Conclusions- The 1/2SH and π/6SH are accurate, reliable, and rapid methods for calculating hematoma volumes. The accuracy and reliability of 1/2SH were slightly higher than those of π/6SH.

TRPC1 inhibits the proliferation and migration of estrogen receptor-positive Breast cancer and gives a better prognosis by inhibiting the PI3K/AKT pathway.

PURPOSE: Previous studies have indicated that transient receptor potential (TRP) channels can influence cancer development. The TRPC subfamily consists of seven subtypes, TRPC1 - TRPC7. Interestingly, the expression levels of TRPC1 have been shown to be totally different in different breast cancer cell lines. Nevertheless, the underlying mechanism remains unknown. In this study, we explore the significance of TRPC1 expression in breast cancer. METHODS: Immunohistochemical TRPC1 staining was performed in 278 samples. TRPC1 expression in different breast tissues were examined. Then, the influence of TRPC1 on migration, invasion and proliferation was explored. We analyzed the protein of TRPC1 by Western blot to prove which pathway may be involved in. Finally, we use online database to predict the prognosis of TRPC1 in breast cancer. RESULTS: Through immunohistochemistry and in vitro experiments, we found that the expression level of TRPC1 was higher in breast cancer cells as compared with that in normal breast epithelial cells. Moreover, the expression level of TRPC1 was different between estrogen receptor-positive (ER +) and -negative (ER -) breast cancer. It was shown that TRPC1 inhibited MCF7 cell proliferation, migration, and invasion in vitro. Western blotting revealed that TRPC1 inhibited the PI3K/AKT pathway and epithelium-mesenchymal transformation, leading to subsequent inhibition of cell proliferation and metastasis. In luminal A and luminal B patients, those with high TRPC1 expression had a better prognosis. On the contrary, in basal-like and triple-negative breast cancer (TNBC) subtypes, patients with high-TRPC1 expression had a worse prognosis. CONCLUSIONS: We confirmed that TRPC1 was high expression in breast cancer. Overexpression of TRPC1 inhibits proliferation and migration of ER + breast cancer and gives a better prognosis by inhibiting PI3K/AKT pathway activation. TRPC1 may be an independent prognostic predictor in breast cancer patients.

Synthesis, in vitro ADME profiling and in vivo pharmacological evaluation of novel glycogen phosphorylase inhibitors.

A small set of indole-2-carboxamide derivatives identified from a high-throughput screening campaign has been described as a novel, potent, and glucose-sensitive inhibitors of glycogen phosphorylase a (GPa). Among this series of compounds, compound 2 exhibited moderate GP inhibitory activity (IC50 = 0.29 µM), good cellular efficacy (IC50 = 3.24 µM for HepG2 cells and IC50 = 7.15 µM for isolated rat hepatocytes), together with good absorption, distribution, metabolism, and elimination (ADME) profiles. The in vivo animal study revealed that compound 2 significantly inhibited an increase of fasting blood glucose level in adrenaline-induced diabetic mice.

Neuroprotective Activity of Cerebrosides from Typhonium giganteum by Regulating Caspase-3 and Bax/Bcl-2 Signaling Pathways in PC12 Cells.

An investigation of the potential neuroprotective natural product constituents of the rhizomes of Typhonium giganteum led to the isolation of two new cerebrosides, typhonosides E (1) and F (2), along with 11 known analogues (3-13). The structures of compounds 1 and 2 were elucidated by spectroscopic data interpretation. The activity of these compounds against glutamate-induced cell apoptosis was investigated in PC12 cells. All compounds exhibited such activity, which was related to the length of the fatty acyl chain. Among them, longan cerebroside II (11), with the longest fatty acyl chain, showed the most potent protective effect in PC12 cells from glutamate injury, with an EC50 value of 2.5 µM. Moreover, at the molecular level, longan cerebroside II (11) downregulated the expression of caspase-9, caspase-3, and Bax, upregulated the expression of Bcl-2, and decreased the level of cytosolic cytochrome c in a concentration-dependent manner.

Rheum emodin inhibits enterovirus 71 viral replication and affects the host cell cycle environment.

Human enterovirus 71 (EV71) is the primary causative agent of recent large-scale outbreaks of hand, foot, and mouth disease (HFMD) in Asia. Currently, there are no drugs available for the prevention and treatment of HFMD. In this study, we compared the anti-EV71 activities of three natural compounds, rheum emodin, artemisinin and astragaloside extracted from Chinese herbs Chinese rhubarb, Artemisia carvifolia and Astragalus, respectively, which have been traditionally used for the treatment and prevention of epidemic diseases. Human lung fibroblast cell line MRC5 was mock-infected or infected with EV71, and treated with drugs. The cytotoxicity of the drugs was detected with MTT assay. The cytopathic effects such as cell death and condensed nuclei were morphologically observed. The VP1-coding sequence required for EV71 genome replication was assayed with qRT-PCR. Viral protein expression was analyzed with Western blotting. Viral TCID50 was determined to evaluate EV71 virulence. Flow cytometry analysis of propidium iodide staining was performed to analyze the cell cycle distribution of MRC5 cells. Rheum emodin (29.6 µmol/L) effectively protected MRC5 cells from EV71-induced cytopathic effects, which resulted from the inhibiting viral replication: rheum emodin treatment decreased viral genomic levels by 5.34-fold, viral protein expression by less than 30-fold and EV71 virulence by 0.33107-fold. The fact that inhibition of rheum emodin on viral virulence was much stronger than its effects on genomic levels and viral protein expression suggested that rheum emodin inhibited viral maturation. Furthermore, rheum emodin treatment markedly diminished cell cycle arrest at S phase in MRC5 cells, which was induced by EV71 infection and favored the viral replication. In contrast, neither astragaloside (50 µmol/L) nor artemisinin (50 µmol/L) showed similar anti-EV71 activities. Among the three natural compounds tested, rheum emodin effectively suppressed EV71 viral replication, thus is a candidate anti-HFMD drug.

5-Hydroxymethylcytosine expression is associated with poor survival in cervical squamous cell carcinoma.

OBJECTIVE: Deoxyribonucleic acid methylation is an important epigenetic modification that is frequently altered in cancer. Recent reports showed that the level of 5-hydroxymethylcytosine was altered in various types of cancers. The influence of deoxyribonucleic acid methylation in cervical squamous cell carcinoma is not fully understood. In this study, we investigated 5-hydroxymethylcytosine and ten-eleven translocation expression in cervical squamous cell carcinoma and whether they are associated with poor survival in cervical squamous cell carcinoma. METHODS: We detected the expression of 5-hydroxymethylcytosine, 5-methylcytosine and TET1/2/3 in 140 patients with cervical squamous cell carcinoma and 40 patients with normal cervical tissues by immunohistochemistry. We assessed the prognostic values of 5-hydroxymethylcytosine, 5-methylcytosine and TET2 in the clinical outcome of cervical squamous cell carcinoma. RESULTS: Expression of 5-hydroxymethylcytosine was significantly decreased in cervical squamous cell carcinoma compared with normal cervix tissues. In contrast, 5-methylcytosine expression was significantly increased in cervical squamous cell carcinoma compared with normal cervix tissues. Moreover, expression of TET2, but not TET1 and TET3, was decreased in cervical squamous cell carcinoma. Our study showed that the decreased level of 5-hydroxymethylcytosine predicts poor prognosis of cervical squamous cell carcinoma patients. The expression of 5-hydroxymethylcytosine was an independent prognostic factor for both disease-free and overall survival of cervical squamous cell carcinoma patients. CONCLUSIONS: In cervical squamous cell carcinoma, less aggressive tumor behavior was correlated with 5-hydroxymethylcytosine and TET2. Our data indicated that 5-hydroxymethylcytosine may become a prognostic marker for cervical squamous cell carcinoma and the decreased expression of TET2 may be an underlying mechanism for decreased 5-hmC in cervical squamous cell carcinoma.

Prognostic values of 5-hmC, 5-mC and TET2 in epithelial ovarian cancer.

PURPOSE: DNA methylation is an important epigenetic modification that is frequently altered in cancer. Recent reports showed that the level of 5-hydroxymethylcytosine (5-hmC) was altered in various types of cancers. The influence of DNA methylation in epithelial ovarian cancer (EOC) is not fully understood. Therefore, the aim of the present study was to investigate factors involved in DNA demethylation in EOC compared with normal ovarian tissues. METHODS: We examined the expression of 5-hmC, 5-mC, and TET2 by immunohistochemistry in 130 cases of EOC and 40 cases of normal ovarian tissues. We assessed the prognostic values of 5-hmC, 5-mC, and TET2 in clinical outcome of EOC. RESULTS: We discovered a significant decrease in 5-hmC and TET2 expression in EOC compared with normal ovarian tissues. In contrast, there was a significant increase in 5-mC expression in EOC compared with normal ovarian tissues. The expression of 5-hmC, 5-mC, and TET2 correlated with pathologic stage, tumor grading, lymph node metastasis, and vascular thrombosis. Furthermore, decreased level of 5-hmC predicts poor prognosis of EOC patients. The expression of 5-hmC was an independent prognostic factor for overall survival of EOC patients. CONCLUSIONS: The data suggest that loss of 5-hmC is an epigenetic event of EOC, and the expression of 5-hmC could serve as a prognostic factor for EOC.

Physical exercise promotes recovery of neurological function after ischemic stroke in rats.

Although physical exercise is an effective strategy for treatment of ischemic stroke, the underlying protective mechanisms are still not well understood. It has been recently demonstrated that neural progenitor cells play a vital role in the recovery of neurological function (NF) through differentiation into mature neurons. In the current study, we observed that physical exercise significantly reduced the infarct size and improved damaged neural functional recovery after an ischemic stroke. Furthermore, we found that the treatment not only exhibited a significant increase in the number of neural progenitor cells and neurons but also decreased the apoptotic cells in the peri-infarct region, compared to a control in the absence of exercise. Importantly, the insulin-like growth factor-1 (IGF-1)/Akt signaling pathway was dramatically activated in the peri-infarct region of rats after physical exercise training. Therefore, our findings suggest that physical exercise directly influences the NF recovery process by increasing neural progenitor cell count via activation of the IGF-1/Akt signaling pathway.

Histone deacetylases and their inhibitors in inflammatory diseases.

Despite considerable research efforts, inflammatory diseases remain a heavy burden on human health, causing significant economic losses annually. Histone deacetylases (HDACs) play a significant role in regulating inflammation (via histone and non-histone protein deacetylation) and chromatin structure and gene expression regulation. Herein, we present a detailed description of the different HDACs and their functions and analyze the role of HDACs in inflammatory diseases, including pro-inflammatory cytokine production reduction, immune cell function modulation, and anti-inflammatory cell activity enhancement. Although HDAC inhibitors have shown broad inflammatory disease treatment potentials, their clinical applicability remains limited because of their non-specific effects, adverse effects, and drug resistance. With further research and insight, these inhibitors are expected to become important tools for the treatment of a wide range of inflammatory diseases. This review aims to explore the mechanisms and application prospects of HDACs and their inhibitors in multiple inflammatory diseases.

Physical Exercise Improves the Neuronal Function in Ischemic Stroke Via Microglial CB2R/P2Y12 Signaling.

Physical exercise (PE) may be the single most important and accessible lifestyle habit throughout life, it inhibits the neuroinflammatory response and protects the brain against damage. As the innate cells in brain, microglia undergo morphological and functional changes to communicate with neurons protecting the neurons from injury. Herein, aiming at exploring the effects of PE on the communication between microglia-neuron during acute ischemic cerebral infarction, we carried out running wheel training before the conduction of transient middle cerebral artery occlusion (tMCAO) in C57BL/6 J and Cx3cr1-GFP mice. We found that microglial P2Y12 expression in the peri-infarct area was decreased, microglial dynamics and microglia-neuron communications were impaired, using in vivo two-photon imaging. PE up-regulated the microglial P2Y12 expression, increased the microglial dynamics, and promoted the contacts of microglia with neurons. As a result, PE inhibited neuronal Ca2+ overloads and protected against damage of the neuronal mitochondria in acute tMCAO. Mechanistically, PE increased the cannabinoid receptor 2 (CB2R) in microglia, promoted the phosphorylation of Nrf2 (NF-E2-related factor 2) at ser-344, increased the transcription factor level of Mafk, and up-regulated the level of P2Y12, whereby PE increased the levels of CB2R to promote microglia-neuron contacts to monitor and protect neuronal function.