Project description:We used microRNA microarrays to identify dysregulated microRNAs in CD4+ T cells isolated from brains of EAE mice treated with vehicle or THC+CBD.
Project description:We used microRNA microarrays to identify dysregulated microRNAs in mononuclear cells isolated from SEB-injured mice treated with Vehicle or THC
Project description:The present study had the purpose to analyze the transcriptional state of oligodendrocytes in an animal model of multiple scleroris resembling autoimmune neuroinflammation and compared with control mice treated with ovalbumin. The results revealed that oligodendrocytes from the EAE (experimental autoimmune encephalomyelitis) model upregulate genes that are involved in immune processes providing evidence that oligodendrocytes can develop an immune phenotype in particular neuroinflammatory conditions.
Project description:STAT5 plays a critical role in mediating cellular responses following cytokine stimulation. The activated STAT5 proteins can form dimers and tetramers with distinct biological functions. The role of STAT5 tetramerization in autoimmune-mediated neuroinflammation has not been investigated. Using the STAT5 tetramer-deficient Stat5a-Stat5b N-domain double knock-in (DKI) mouse strain, we report here that STAT5 tetramers promote the pathogenesis of experimental autoimmune encephalomyelitis (EAE). The mild EAE phenotype observed in DKI mice correlates with the impaired extravasation of pathogenic Th17 cells and interactions between Th17 cells and monocyte-derived cells (MDCs) in the meninges. We further demonstrated that STAT5 tetramerization regulates the GM-CSF-dependent production of CCL17 by MDCs. Importantly, DKI Th17 cells expanded with CCL17 exhibit more severe EAE. Mechanistically, the effect of CCL17 is dependent on the activity of the integrin VLA-4. Thus, our study uncovered a novel GM-CSF-STAT5 tetramer-CCL17 pathway that promotes autoimmune neuroinflammation via the regulation of Th17 cell migration.
Project description:Olfactory dysfunction is an underestimated symptom in multiple sclerosis (MS). Here, we examined the pathogenic mechanisms underlying inflammation-induced dysfunction of the olfactory bulb using the animal model of MS, experimental autoimmune encephalomyelitis (EAE). Reduced olfactory function in EAE was associated with the degeneration of short-axon neurons, immature neurons, and mitral cells, together with their synaptic interactions and axonal repertoire. To dissect the mechanisms underlying the susceptibility of mitral cells, the main projection neurons of the olfactory bulb, we profiled their responses to neuroinflammation by single-nucleus RNA sequencing. Neuroinflammation resulted in the induction of potassium channel transcripts in mitral cells, which was reflected in reduced halothane-induced outward currents of these cells, likely contributing to the impaired olfaction in EAE animals.
Project description:The immune regulatory defects that promote neuroinflammation in multiple sclerosis (MS) remain unclear. We show that a specific regulatory T (Treg) cell subpopulation expressing Notch3 is increased in individuals with MS and in mice with experimental autoimmune encephalomyelitis (EAE). Notch3 is induced by the gut microbiota by toll-like receptor (TLR)-dependent mechanisms to promote EAE severity. Notch3 interacts with delta-like ligand 1 (DLL1) on microglia to subvert Treg cells into T helper 17 (Th17) cells. Notch3 Treg-specific deletion inhibits EAE by preventing Treg cell destabilization while simultaneously promoting the expansion of a novel tissue-resident neuropeptide receptor 1 (NPY1R)+ Treg cell population that suppressed pathogenic IFNg+ and GM-CSF+ T cells. Our studies thus identify altered Treg cell population dynamics as a fundamental pathogenic mechanism in autoimmune neuroinflammation.
Project description:Cannabinoids are known to exert immunosuppressive activities. However, the mechanisms which contribute to these effects are unknown. Using lipopolysaccharide (LPS) to activate BV-2 microglial cells, we examined how Δ9-tetrahydrocannabinol (THC), the major psychoactive component of marijuana, and cannabidiol (CBD) the non-psychoactive component, modulate the inflammatory response through miRNA expression
Project description:Neuroinflammation causes neuronal injury in multiple sclerosis (MS) and other neurological diseases. MicroRNAs (miRNAs) are central modulators of cellular stress responses, but knowledge about miRNA–mRNA interactions that determine neuronal outcome during inflammation is limited. Here, we combined unbiased neuron-specific miRNA with mRNA sequencing to assemble the regulatory network that mediates robustness against neuroinflammation. As a critical miRNA-network hub we defined miR-92a. Genetic deletion of miR-92a exacerbated the disease course of mice undergoing experimental autoimmune encephalomyelitis (EAE), whereas miR-92a overexpression protected neurons against excitotoxicity. As a key miR-92a target transcript, we identified cytoplasmic polyadenylation element-binding protein 3 (Cpeb3) that was suppressed in inflamed neurons in mouse EAE and human MS. Accordingly, Cpeb3 deletion improved neuronal resistance to excitotoxicity and ameliorated EAE. Together, we discovered that the miR-92a–Cpeb3 axis confers neuronal robustness against inflammation and serves as potential target for neuroprotective therapies.