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Aims: Chronic alcohol exposure leads to persistent neurological disorders, which are mainly attributed to neuroinflammation and apoptosis. Stimulator of IFN genes (STING) is essential in the cytosolic DNA sensing pathway and is involved in inflammation and cellular death processes. This study was to examine the expression pattern and biological functions of STING signaling in alcohol use disorder (AUD). Methods: Cell‐free DNA was extracted from human and mouse plasma. C57BL/6J mice were given alcohol by gavage for 28 days, and behavior tests were used to determine their mood and cognition. Cultured cells were treated with ethanol for 24 hours. The STING agonist DMXAA, STING inhibitor C‐176, and STING‐siRNA were used to intervene the STING. qPCR, western blot, and immunofluorescence staining were used to assess STING signaling, inflammation, and apoptosis. Results: Circulating cell‐free mitochondrial DNA (mtDNA) was increased in individuals with AUD and mice chronically exposed to alcohol. Upregulation of STING signaling under alcohol exposure led to inflammatory responses in BV2 cells and mitochondrial apoptosis in PC12 cells. DMXAA exacerbated alcohol‐induced cognitive impairment and increased the activation of microglia, neuroinflammation, and apoptosis in the medial prefrontal cortex (mPFC), while C‐176 exerted neuroprotection. Conclusion: Activation of STING signaling played an essential role in alcohol‐induced inflammation and mitochondrial apoptosis in the mPFC. This study identifies STING as a promising therapeutic target for AUD. [ABSTRACT FROM AUTHOR]

Background and aims: Observational studies have yielded conflicting results on the association of prescription opioid use (POU) with the risk of cardiovascular diseases (CVD). Residual confounding and potential reverse causality are inevitable in such conventional observational studies. This study used Mendelian randomization (MR) design to estimate the causal effect of POU on the risk of CVD, including coronary heart disease (CHD), myocardial infarction (MI) and ischemic stroke (IS), as well as their common risk factors. Design We estimated the causal effect of genetic liability for POU on CVD in a two‐sample MR framework. Complementary sensitivity analyses were conducted to test the robustness of our results. Setting: Genome‐wide association studies (GWAS) that were based on predominantly European ancestry. Participants: The sample sizes of the GWAS used in this study ranged from 69 033 to 757 601 participants. Measurements Genetic variants predictive of the POU and their corresponding summary‐level information in the outcomes were retrieved and extracted from the respective GWAS. Findings Using univariable MR, we found evidence for a causal effect of genetic liability for POU on an increased risk of CHD [odds ratio (OR) = 1.09; 95% confidence interval (CI) = 1.02–1.16; P = 0.008] and MI (OR = 1.13; 95% CI = 1.04–1.22; P = 0.002). In multivariable MR, the association remained after accounting for comorbid pain conditions, but was attenuated with adjustment for potential mediators, including body mass index (BMI), waist circumference (WC) and type 2 diabetes (T2D). Conclusion: Mendelian randomization estimates provide robust evidence for the causal effects of genetic liability for prescription opioid use on an increased risk of coronary heart disease and myocardial infarction, which might be mediated by obesity‐related traits. [ABSTRACT FROM AUTHOR]

Background: Glioblastoma multiforme (GBM) induces tumor immunosuppression through interacting with tumor-infiltrating microglia or macrophages (TAMs) with an unclear pathogenesis. Enhancer of zeste homolog 2 (EZH2) is abundant in GBM samples and cell lines and is involved in GBM proliferation, cell cycle, and invasion, whereas its association with innate immune response is not yet reported. Herein, the aim of this study was to investigate the role of EZH2 in GBM immune.Methods: Co-culturing models of human/murine GBM cells with PBMC-derived macrophages/primary microglia were employed. EZH2 mRNAs and function were suppressed by siEZH2 and DZNep. Real-time PCR and flow cytometry were used to determine levels of microglia/macrophages markers. The fluorescence-labeled latex beads and flow cytometry were utilized to evaluate phagocytic abilities of microglia. CCK8 assay was performed to assess microglia proliferation.Results: EZH2 inhibition led to significant reduction of TGFβ1-3 and IL10 and elevation of IL1β and IL6 in human and murine GBM cells. More importantly, EZH2 suppression in GBM cells resulted in significant increase of M1 markers (TNFα and iNOS) and decrease of a pool of M2 markers in murine microglia. The proportion of CD206+ cells was decreased in PBMC-derived macrophages as co-incubated with EZH2-inhibited GBM cells. Functional researches showed that phagocytic capacities of microglia were significantly ameliorated after EZH2 inhibition in co-culturing GBM cells and microglia proliferation was declined after addition of TGFβ2 antibodies to co-incubated GBM cells with EZH2 inhibition. Besides, we found that EZH2 suppression in GBM cells enhanced co-culturing microglia engulfment through activation of iNOS.Conclusions: Our data demonstrates that EZH2 participates in GBM-induced immune deficient and EZH2 suppression in GBM can remodel microglia immune functions, which is beneficial for understanding GBM pathogenesis and suggests potential targets for therapeutic approaches. [ABSTRACT FROM AUTHOR]

Purpose: The family of Toll-like receptors (TLRs) has recently been reported to play a role in ischemic injury, but the time course and cell types of the post-stroke TLR9 upregulation remain unclear. In this study, we investigated the dynamic changes of TLR9 expression and the expression of TLR9 in neurons and glial cells after cerebral ischemia reperfusion in mice.Methods: Focal cerebral ischemia was induced by middle cerebral artery occlusion for 90 min in male C57BL/6 mice. The TLR9 expression levels in the tissue surrounding the infarct were detected by Western Blot at 6 h, 3 d, 7 d, 14 d, 21 d, and 28 d after reperfusion. The expression of TLR9 in neurons and glial cells was observed by immunofluorescence staining.Results: The expression of TLR9 protein first increased and then decreased, with the peak observed at 14 d–21 d. Only small punctate intracellular TLR9 was occasionally observed in the neurons at each time point, and the TLR9-positive rate showed no difference at different time points. By contrast, the activated microglia gathered at the margin of the infarct, and the intracellular TLR9 changed from scattered small punctate to coarse and lumpy. The TLR9-positive rate of microglia was first increased and then decreased with time, with the peak observed at 3 d. No positive TLR9 staining was found in the astrocytes and oligodendrocytes.Conclusions: TLR9 expression showed dynamic changes for a long period of time and microglias were the main brain cells to express TLR9 after cerebral ischemia and reperfusion. [ABSTRACT FROM PUBLISHER]