Introduction: Neurodegeneration resulting from pathogen invasion or tissue damage has been associated with activation of microglia, and exacerbated by the release of neurotoxic mediators such as pro-inflammatory cytokines, chemokines and reactive oxygen species. Activation of microglia stimulated by lipopolysaccharide is mediated in part by GSK-3 signaling molecule. Induced IL-10 expression via GSK-3 inhibition is noteworthy since IL-10 has been remarkably shown to suppress inflammation. Objectives: We aimed to inactivate microglia through inhibition of GSK-3 signaling and to determine its effects on the production of pro- and anti-inflammatory mediators. Methods: LPS-stimulated BV-2 cells were treated with a GSK-3 inhibitor (LiCl, NP12, SB216763 or CHIR99021). Inhibition of GSK-3 was determined by the phosphorylation status of GSK-3β. The effects of GSK-3 inhibition on microglial inflammatory response were investigated by examining various mediators and CD200R marker. Production of nitric oxide (NO), glutamate and pro- and anti-inflammatory cytokines were measured using flow cytometry, Griess assay, glutamate assay and Cytometric Bead Array (CBA) respectively. Results: GSK-3β signaling in LPS-stimulated microglia was blocked by GSK-3 inhibitor through increased phosphorylation at Serine 9 residue. GSK-3 inhibitors had also led to reducing in microglia activity via increased expression of CD200R. Inhibition of GSK-3 also diminished inflammatory mediators such as nitric oxide (NO), glutamate, pro-inflammatory cytokines (TNF-α and IL-6) and chemokine, MCP-1. Reduction of pro-inflammatory mediators by GSK-3 inhibitor was coincided with increased IL-10 production. Conclusions: Suppression of microglia-mediated inflammatory response was facilitated by GSK-3 inhibition with associated increased in IL-10 production.
Microglia

The transwell migration assay is commonly used for assessing cell migration. It involves the enumeration of cells that have migrated across a pore-containing membrane. We describe a randomised approach to quantifying migrated cells and compare it to a conventional full cell count. We used ATP as a chemoattractant and automatic cell quantification performed on all fields (Full count; FC) or 10 randomly selected fields (Randomised count; RC). The two methods were compared by evaluating standard deviations (SD), coefficient of variation (CV) and using the Bland-Altman analysis. The dispersion of data is higher with the RC approach (3.77-6.66% CV for control; 3.89-4.48% CV for ATP-treated wells) compared to FC (0.27-0.46% CV for control; 0.05-0.09% CV for ATP-treated wells), but are acceptable considering that the number of migrated cells are in the thousands. Both methods verified that an ATP migration assay for BV2 microglia was established, demonstrating that the RC approach is reliable and comparable to a full count.
Microglia

No abstract available.
Animals ; Hyperalgesia ; Microglia ; Rats ; Up-Regulation

Microglia are the resident innate immune cells in the brain. Under endogenous or exogenous stimulates, they become activated and play an important role in the neurodegenerative diseases. Microglial phagocytosis is a process of receptor-mediated engulfment and degradation of apoptotic cells. In addition, microglia can phagocyte brain-specific cargo, such as myelin debris and abnormal protein aggregation. However, recent studies have shown that microglia can also phagocyte stressed-but-viable neurons, causing loss of neurons in the brain. Thus, whether microglial phagocytosis is beneficial or not in neurodegenerative disease remains controversial. This article reviews microglial phagocytosis related mechanisms and its potential roles in neurodegenerative diseases, with an attempt to provide new insights in the treatment of neurodegenerative diseases.
Humans ; Microglia ; cytology ; Neurodegenerative Diseases ; physiopathology ; Phagocytosis

Humans ; Microglia ; Spinal Cord ; Neuralgia ; Hyperalgesia

Microglia/physiology* ; Neurons/physiology* ; Cells, Cultured

Dependovirus/genetics* ; Microglia ; Cells, Cultured ; Transduction, Genetic

Hypothermia is considered a useful intervention for limiting pathophysiological changes after brain injury. Local hypothermia is a relatively safe and convenient intervention that circumvents many of the complications associated with systemic hypothermia. However, successful hypothermia treatment requires careful consideration of several factors including its practicality, feasibility, and associated risks. Here, we review the protective effects-and the cellular mechanisms that underlie them-of delayed and prolonged local hypothermia in rodent and canine brain injury models. The data show that the protective effects of therapeutic hypothermia, which mainly result from the modulation of inflammatory glial dynamics, are limited. We argue that decompressive craniectomy can be used to overcome the limitations of local brain hypothermia without causing histological abnormalities or other detrimental effects to the cooled area. Therefore, delayed and prolonged local brain hypothermia at the site of craniectomy is a promising intervention that may prove effective in the clinical setting.
Astrocytes ; Brain Injuries ; Brain* ; Decompressive Craniectomy* ; Hypothermia* ; Microglia ; Rodentia ; Stroke

Translocator protein 18 kDa (TSPO) is a mitochondrial protein highly expressed on reactive microglia and astrocytes, and is considered as a biomarker for neurodegeneration and brain damage, especially neuroinflammation. Toll-like receptors (TLRs) are closely related with inflammatory responses of microglia and astrocytes and these signaling pathways regulate neuroinflammation. Previous reports have identified the anti-inflammatory effects of TSPO ligands, however study of their effects in relation to the TLR signaling was limited. Here, we investigated the effects of five representative TSPO ligands on microglia and astrocytes following activation by various TLR ligands. Our results show that TSPO ligands reduce the pro-inflammatory response elicited by the TLR ligands with more profound effects on microglia than astrocytes.
Astrocytes* ; Brain ; Ligands* ; Microglia* ; Mitochondrial Proteins ; Toll-Like Receptors

Microglia regulate the secretion of various immunomediators in central nervous system diseases. Microglial autophagy is the crucial process for cell's survival and cytokine productions. Recent studies have reported that several microRNAs are involved in the autophagy system. miR-Let7A is such a microRNA that plays a role in various inflammation responses, and is magnified as a key modulator particularly in the autophagy system. In present study, we investigated whether miR-Let7A is involved in autophagy in activating microglia. Overexpression of miR-Let7A in LPS-stimulated BV2 microglial cells promoted the induction of the autophagy related factors such as LC3II, Beclin1, and ATG3. Our results suggest a potential role of miR-Let7A in the autophagy process of microglia during CNS inflammation.
Autophagy* ; Central Nervous System Diseases ; Inflammation ; Microglia* ; MicroRNAs