Project description:Translating affinity purification (TRAP)-mediated analysis of kidney endothelial translatome of bulk kidney RNA-seq from mice 15 hours after an intraperitoneal challenge with 250 micrograms of LPS per mouse.
Project description:Neuroinflammation plays an important role in the occurrence and development of neurological diseases. In addition to microglia, the role of astrocytes in neuroinflammation has gradually attracted attention. Photobiomodulation (PBM), as a non-invasive, safe and effective treatment, has been shown to alleviate neuroinflammation and show potential in improving astrocyte activation. In this study, by analyzing the effects at different times, the spatiotemporal regulation and molecular mechanism of PBM on astrocytes were deeply explored. The results showed that PBM significantly attenuated LPS-induced upregulation of inflammatory factors and mitochondrial dysfunction in astrocytes under LPS stimulation for 4 hours and 24 hours. RNA-seq analysis showed that the JAK-STAT pathway played an important role in the early stage of astrocyte inflammatory response. PBM can promote the expression of Socs3 by activating Stat5a translocation to the nucleus, further inhibit the overactivation of the JAK-STAT inflammatory signaling pathway, and thus alleviate astrocyte inflammation. Taken together, this study provides new insights into the molecular mechanism of the potential application of PBM in the treatment of neuroinflammation.
Project description:RNA-seq analysis of kidney endothelium and whole kidney from mice 15 hours after an intraperitoneal challenge with 250 micrograms of LPS per mouse.
Project description:The vascular endothelium may play a role in the response to infectious agents and in the pathophysiology of disease processes resulting in capillary leak such as septic shock and acute respiratory distress syndrome. In order to study the effect of endotoxin on endothelial cell function, human lung microvascular endothelial cells in culture were exposed to lipopolysaccharide (LPS), 10 ng, for 4, 8, or 24 hours and changes in mRNA expression were studied using Affymetrix HG U133plus2 gene arrays. A principal components analysis revealed that LPS treatment was the primary source of variability in the data. LPS treatment of endothelial cells for 4, 8, or 24 hours resulted in the upregulation by two-fold or greater of 275, 260 and 141 genes respectively. LPS treatment resulted in the down regulation by 50% or greater of 176, 263 and 79 genes at 4, 8, or 24 hours respectively. Up regulated genes at 4 or 8 hours were enriched in those encoding for cytokines, secreted proteins, cell membrane proteins and proteins controlling signal transduction and transcriptional regulation. Down regulated genes at each of the time points included those coding for cell membrane proteins, transcriptional regulation and metabolism. At each time point, a significant proportion of the genes identified as changed were unique to that time point. Experiment Overall Design: In order to study the effect of endotoxin on endothelial cell function, human lung microvascular endothelial cells in culture were exposed to lipopolysaccharide (LPS), 10 ng, for 4, 8, or 24 hours and changes in mRNA expression were studied using Affymetrix HG U133plus2 gene arrays. Controls for each time point with no LPS exposure were also run. An N of 4 for each time point and treatment was used.
Project description:Four daily intraperitoneal injections of the Gram-negative bacterial endotoxin lipopolysaccharide (LPS) transiently protects the cerebral cortex against traumatic brain injury. Underlying mechanisms associated with this neuroprotection include increased neuronal production of anti-apoptotic and neurotrophic molecules, microglial-mediated displacement of inhibitory presynaptic terminals innervating the soma of cortical projection neurons, and synchronized firing of cortical projection neurons. The molecular mechanisms responsible for inducing this neuroprotection and microglial activation are unknown. A fundamental question is whether LPS enters the central nervous system (CNS) or mediates it actions on the luminal surface of brain endothelial cells. In this study, we demonstrate that LPS injected into the peritoneum does not enter the CNS or alter tight junctions of brain endothelial cells. However, LPS activation of vascular endothelial cells was substantiated by increased expression of activation markers (CD54 and CD105) and the LPS receptor, TLR4, on CD31-positive brain endothelial cells isolated by flow cytometry. Transcript analyses further revealed significant upregulation of Cxcl10, C3, Ccl2, Il1b, Cxcl2, and Cxcl1 in these activated endothelial cells, consistent with identification of MyD88 as a regulator of these transcripts by pathway analysis. Using conditional brain endothelial gene ablation strategies, we establish that MyD88-dependent endothelial TLR4 signaling and endothelial Cxcl10 expression are essential for LPS-induced neuroprotection and microglial activation. CXCL10 production by brain endothelial cells in response to circulating TLR ligands thus provides a pathway to directly or indirectly signal to CXCR3 on neurons and/or microglia. Targeting activation of brain endothelial receptors provides an attractive and practical approach for inducing transient neuroprotection.
Project description:Effects of SOCS3 on the transcriptional response of bone marrow-derived macrophages to IL-6. Fetal liver cells from SOCS3+/+ or SOCS3-/- embryos were used to reconstitute recipient mice. Donor derived bone marrow from these mice was differentiated to macrophages. Macrophages were either unstimulated, or stimulated for 100 or 400 minutes with 10 ng/ml IL-6. Keywords = macrophage, SOCS3, IL-6, interferon Keywords: repeat sample
Project description:Effects of SOCS3 on the transcriptional response of bone marrow-derived macrophages to IL-6. Fetal liver cells from SOCS3+/+ or SOCS3-/- embryos were used to reconstitute recipient mice. Donor derived bone marrow from these mice was differentiated to macrophages. Macrophages were either unstimulated, or stimulated for 100 or 400 minutes with 10 ng/ml IL-6. Keywords = macrophage, SOCS3, IL-6, interferon
Project description:The responses of macrophages to lipopolysaccharide (LPS) might determine the direction of clinical manifestations of sepsis, which is the immune response against severe infection. Meanwhile, the enhancer of zeste homologue 2 (Ezh2), a histone lysine methyltransferase of epigenetic regulation, might interfere with LPS response. With a single LPS stimulation, Ezh2 null(Ezh2flox/flox; LysM-Crecre/−) macrophages demonstrated lower supernatant TNF-α than Ezh2 control (Ezh2fl/fl; LysM-Cre−/−), perhaps due to an upregulation of Socs3, which is a suppressor of cytokine signaling 3, due to the loss of the Ezh2 gene. In LPS tolerance, Ezh2 null macrophages indicated higher supernatant TNF-α and IL-6 than the control, supporting an impact of the loss of the Ezh2 inhibitory gene. In parallel, Ezh2 null mice demonstrated lower serum TNF-α and IL-6 than the control mice after an LPS injection, indicating a less severe LPS-induced hyper-inflammation in Ezh2 null mice. In conclusion, an absence of Ezh2 in macrophages resulted in less severe LPS-induced inflammation, as indicated by low serum cytokines, with less severe LPS tolerance, as demonstrated by higher cytokine production, partly through the upregulated Socs3.