Journal: Journal of neuroinflammation
In the SOD1(G93A) mutant rat model of amyotrophic lateral sclerosis (ALS), neuronal death and rapid paralysis progression are associated with the emergence of activated aberrant glial cells that proliferate in the degenerating spinal cord. Whether pharmacological downregulation of such aberrant glial cells will decrease motor neuron death and prolong survival is unknown. We hypothesized that proliferation of aberrant glial cells is dependent on kinase receptor activation, and therefore, the tyrosine kinase inhibitor masitinib (AB1010) could potentially control neuroinflammation in the rat model of ALS.
BackgroundThe fatty acid amide palmitoylethanolamide (PEA) has been studied extensively for its anti-inflammatory and neuroprotective actions. The lipidic nature and large particle size of PEA in the native state may limit its solubility and bioavailability when given orally, however. Micronized formulations of a drug enhance its rate of dissolution and reduce variability of absorption when orally administered. The present study was thus designed to evaluate the oral anti-inflammatory efficacy of micronized/ultramicronized versus nonmicronized PEA formulations.MethodsMicronized/ultramicronized PEA was produced by the air-jet milling technique, and the various PEA preparations were subjected to physicochemical characterization to determine particle size distribution and purity. Each PEA formulation was then assessed for its anti-inflammatory effects when given orally in the carrageenan-induced rat paw model of inflammation, a well-established paradigm of edema formation and thermal hyperalgesia.ResultsIntraplantar injection of carrageenan into the right hind paw led to a marked accumulation of infiltrating inflammatory cells and increased myeloperoxidase activity. Both parameters were significantly decreased by orally given micronized PEA (PEA-m; 10 mg/kg) or ultramicronized PEA (PEA-um; (10 mg/kg), but not nonmicronized PeaPure (10 mg/kg). Further, carrageenan-induced paw edema and thermal hyperalgesia were markedly and significantly reduced by oral treatment with micronized PEA-m and ultramicronized PEA-um at each time point compared to nonmicronized PeaPure. However, when given by the intraperitoneal route, all PEA formulations proved effective.ConclusionsThese findings illustrate the superior anti-inflammatory action exerted by orally administered, micronized PEA-m and ultramicronized PEA-um, versus that of nonmicronized PeaPure, in the rat paw carrageenan model of inflammatory pain.
Multiple sclerosis (MS) is an autoimmune inflammatory and neurodegenerative disease of the central nervous system (CNS). It is widely accepted that inflammatory cells play major roles in the pathogenesis of MS, possibly through the use of serine protease granzyme B (GrB) secreted from the granules of cytotoxic T cells. We have previously identified GrB as a mediator of axonal injury and neuronal death. In this study, our goal was to evaluate the effect of GrB inhibition in the human system in vitro, and in vivo in EAE using the newly isolated GrB-inhibitor serpina3n.
Understanding blood-brain barrier responses to inflammatory stimulation (such as lipopolysaccharide mimicking a systemic infection or a cytokine cocktail that could be the result of local or systemic inflammation) is essential to understanding the effect of inflammatory stimulation on the brain. It is through the filter of the blood-brain barrier that the brain responds to outside influences, and the blood-brain barrier is a critical point of failure in neuroinflammation. It is important to note that this interaction is not a static response, but one that evolves over time. While current models have provided invaluable information regarding the interaction between cytokine stimulation, the blood-brain barrier, and the brain, these approaches-whether in vivo or in vitro-have often been only snapshots of this complex web of interactions.
Neuroinflammation has long been considered a driver of Alzheimer’s disease progression. However, experiments developed to explore the interaction between neuroinflammation and Alzheimer’s disease (AD) pathology showed a surprising reduction in amyloid beta (Aβ) plaque deposition. We sought to understand this unexpected outcome by examining microglia phenotypes during chronic neuroinflammation.
Increasing evidence indicates that brain inflammation is involved in the pathogenesis of neuropsychiatric diseases. Autism spectrum disorders (ASD) are characterized by social and learning disabilities that affect as many as 1/80 children in the USA. There is still no definitive pathogenesis or reliable biomarkers for ASD, thus significantly curtailing the development of effective therapies. Many children with ASD regress at about age 3 years, often after a specific event such as reaction to vaccination, infection, stress or trauma implying some epigenetic triggers, and may constitute a distinct phenotype. ASD children respond disproportionally to stress and are also affected by food and skin allergies. Corticotropin-releasing hormone (CRH) is secreted under stress and together with neurotensin (NT) stimulates mast cells and microglia resulting in focal brain inflammation and neurotoxicity. NT is significantly increased in serum of ASD children along with mitochondrial DNA. NT stimulates mast cell secretion of mitochondrial DNA that is misconstrued as an innate pathogen triggering an auto-inflammatory response. Lack of the mammalian target of rapamycin (mTOR), which is inhibited by the phosphatase and tensin homolog (PTEN), has been linked to gene mutations associated with higher risk of ASD. CRH, NT and environmental triggers could hyperstimulate the already activated mTOR leading to higher risk for ASD, as well as stimulate mast cell and microglia activation and proliferation. The natural flavonoid luteolin inhibits mTOR, mast cells and microglia and could have a significant benefit in ASD.
Neuroprotection with cannabinoids in Parkinson’s disease (PD) has been afforded predominantly with antioxidant or anti-inflammatory cannabinoids. In the present study, we investigated the anti-inflammatory and neuroprotective properties of VCE-003.2, a quinone derivative of the non-psychotrophic phytocannabinoid cannabigerol (CBG), which may derive its activity at the peroxisome proliferator-activated receptor-γ (PPARγ). The compound is also an antioxidant.
BACKGROUND: Recent evidence suggests that the inducible kinin B1 receptor (B1R) contributes to pathogenic neuroinflammation induced by amyloid-beta (Abeta) peptide. The present study aims at identifying the cellular distribution and potentially detrimental role of B1R on cognitive and cerebrovascular functions in a mouse model of Alzheimer’s disease (AD). METHODS: Transgenic mice overexpressing a mutated form of the human amyloid precursor protein (APPSwe,Ind, line J20) were treated with a selective and brain penetrant B1R antagonist (SSR240612, 10 mg/kg/day for 5 or 10 weeks) or vehicle. The impact of B1R blockade was measured on i) spatial learning and memory performance in the Morris water maze, ii) cerebral blood flow (CBF) responses to sensory stimulation using laser Doppler flowmetry, and iii) reactivity of isolated cerebral arteries using online videomicroscopy. Abeta burden was quantified by ELISA and immunostaining, while other AD landmarks were measured by western blot and immunohistochemistry. RESULTS: B1R protein levels were increased in APP mouse hippocampus and, prominently, in reactive astrocytes surrounding Abeta plaques. In APP mice, B1R antagonism with SSR240612 improved spatial learning, memory and normalized protein levels of the memory-related early gene Egr-1 in the dentate gyrus of the hippocampus. B1R antagonism restored sensory-evoked CBF responses, endothelium-dependent dilations, and normalized cerebrovascular protein levels of endothelial nitric oxide synthase and B2R. In addition, SSR240612 reduced (approximately 50%) microglial, but not astroglial, activation, brain levels of soluble Abeta1-42, diffuse and dense-core Abeta plaques, and it increased protein levels of the Abeta brain efflux transporter lipoprotein receptor-related protein-1 in cerebral microvessels. CONCLUSION: These findings show a selective upregulation of astroglial B1R in the APP mouse brain, and the capacity of the B1R antagonist to abrogate amyloidosis, cerebrovascular and memory deficits. Collectively, these findings provide convincing evidence for a role of B1R in AD pathogenesis.
Chronic infection with the neurotropic parasite Toxoplasma gondii has been implicated in the risk for several neuropsychiatric disorders. The mechanisms, by which the parasite may alter neural function and behavior of the host, are not yet understood completely.
Multiple sclerosis (MS) is characterized by a combination of inflammatory and neurodegenerative processes variously dominant in different stages of the disease. Thus, immunosuppression is the goal standard for the inflammatory stage, and novel remyelination therapies are pursued to restore lost function. Cannabinoids such as9Δ-THC and CBD are multi-target compounds already introduced in the clinical practice for multiple sclerosis (MS). Semisynthetic cannabinoids are designed to improve bioactivities and druggability of their natural precursors. VCE-004.8, an aminoquinone derivative of cannabidiol (CBD), is a dual PPARγ and CB2agonist with potent anti-inflammatory activity. Activation of the hypoxia-inducible factor (HIF) can have a beneficial role in MS by modulating the immune response and favoring neuroprotection and axonal regeneration.