Evidence that myelin repair is crucial for functional recovery in multiple sclerosis (MS) led to the identification of bexarotene (BXT). This clinically promising remyelinating agent activates multiple nuclear hormone receptor subtypes implicated in myelin repair. However, BXT produces unacceptable hyperlipidemia.
View Article and Find Full Text PDFThe transmembrane protein known as the mitochondrial calcium uniporter (MCU) mediates the influx of calcium ions (Ca) into the mitochondrial matrix. An overload of mitochondrial Ca ( Ca) is directly linked to damaging effects in pathological conditions. Therefore, inhibitors of the MCU are important chemical biology tools and therapeutic agents.
View Article and Find Full Text PDFFront Cell Neurosci
July 2023
The neurovascular unit (NVU) is composed of vascular cells, glia, and neurons that form the basic component of the blood brain barrier. This intricate structure rapidly adjusts cerebral blood flow to match the metabolic needs of brain activity. However, the NVU is exquisitely sensitive to damage and displays limited repair after a stroke.
View Article and Find Full Text PDFDysregulation of mitochondrial calcium uptake mediated by the mitochondrial calcium uniporter (MCU) is implicated in several pathophysiological conditions. Dinuclear ruthenium complexes are effective inhibitors of the MCU and have been leveraged as both tools to study mitochondrial calcium dynamics and potential therapeutic agents. In this study, we report the synthesis and characterization of Os245 ([Os(μ-N)(NH)Cl]) which is the osmium-containing analogue of our previously reported ruthenium-based inhibitor Ru265.
View Article and Find Full Text PDFFingolimod, used to treat relapsing-remitting multiple sclerosis (RRMS), reduces motor deficits in mice with established experimental autoimmune encephalomyelitis (EAE). To better characterize the therapeutic effects of fingolimod, kinematic gait analysis was employed to precisely measure movements of a hindleg while EAE mice walked on a treadmill. Relative to the vehicle group, oral dosing with fingolimod, beginning after disease onset (1 mg/kg/day), increased hip heights and knee joint movements, and reduced spinal cord demyelination.
View Article and Find Full Text PDFSleep and circadian rhythm disruptions commonly occur in individuals with schizophrenia. Stable tubule only polypeptide (STOP) knockout (KO) mice show behavioral impairments resembling symptoms of schizophrenia. We previously reported that STOP KO mice slept less and had more fragmented sleep and waking than wild-type littermates under a light/dark (LD) cycle.
View Article and Find Full Text PDFExp Neurol
November 2020
Chronic sleep restriction (CSR) negatively impacts brain functions. Whether microglia, the brain's resident immune cells, play any role is unknown. We studied microglia responses to CSR using a rat model featuring slowly rotating wheels (3 h on/1 h off), which was previously shown to induce both homeostatic and adaptive responses in sleep and attention.
View Article and Find Full Text PDFThe mitochondrial calcium (Ca) uniporter (MCU) mediates high-capacity mitochondrial Ca uptake implicated in ischemic/reperfusion cell death. We have recently shown that inducible MCU ablation in Thy1-expressing neurons renders mice resistant to sensorimotor deficits and forebrain neuron loss in a model of hypoxic/ischemic (HI) brain injury. These findings encouraged us to compare the neuroprotective effects of Ru360 and the recently identified cell permeable MCU inhibitor Ru265.
View Article and Find Full Text PDFExperimental autoimmune encephalomyelitis (EAE) and lysophosphatidylcholine (LPC)-induced demyelination were combined to study remyelination in a pro-inflammatory context. Two groups of female C57BL/6 mice were subjected either to EAE (EAE mice) or injected with just complete Freund's adjuvant (CFA) and pertussis toxin (PTX) followed by bilateral LPC and phosphate buffered saline injections in the corpus callosum on day 7 (CFA controls). Relative to CFA controls, EAE accelerated remyelination and increased innate immune cell activation, lymphocyte infiltration and cytokine gene expression in the LPC lesions.
View Article and Find Full Text PDFBackground: Paired exercise and cognitive training have the potential to enhance cognition by "priming" the brain and upregulating neurotrophins.
Methods: Two-site randomized controlled trial. Fifty-two patients >6 months poststroke with concerns about cognitive impairment trained 50 to 70 minutes, 3× week for 10 weeks with 12-week follow-up.
Recent evidence suggests that clozapine and quetiapine (atypical antipsychotics), tamoxifen (selective-estrogen receptor modulator) and pioglitazone (PPARγ agonist) may improve functional recovery in multiple sclerosis (MS). We have compared the effectiveness of oral administration of these drugs, beginning at peak disease, at reducing ascending paralysis, motor deficits and demyelination in mice subjected to experimental autoimmune encephalomyelitis (EAE). Mice were immunized with an immunogenic peptide corresponding to amino acids 35-55 of the myelin oligodendrocyte glycoprotein (MOG) in complete Freund's adjuvant and injected with pertussis toxin to induce EAE.
View Article and Find Full Text PDFThe mitochondrial calcium uniporter (MCU) mediates high-capacity mitochondrial calcium uptake that stimulates energy production. However, excessive MCU activity can cause ischemic heart injury. To examine if the MCU is also involved in hypoxic/ischemic (HI) brain injury, we have generated conditional MCU knockout mice by tamoxifen (TMX) administration to adult MCU-floxed (MCU) mice expressing a construct encoding Thy1-cre/ERT2-eYFP.
View Article and Find Full Text PDFKinematic gait analysis in the sagittal plane has frequently been used to characterize motor deficits in multiple sclerosis (MS). We describe the application of these techniques to identify gait deficits in a mouse model of MS, known as experimental autoimmune encephalomyelitis (EAE). Paralysis and motor deficits in mice subjected to EAE are typically assessed using a clinical scoring scale.
View Article and Find Full Text PDFThe effects of global mitochondrial calcium (Ca) uniporter (MCU) deficiency on hypoxic-ischemic (HI) brain injury, neuronal Ca handling, bioenergetics and hypoxic preconditioning (HPC) were examined. Forebrain mitochondria isolated from global MCU nulls displayed markedly reduced Ca uptake and Ca-induced opening of the membrane permeability transition pore. Despite evidence that these effects should be neuroprotective, global MCU nulls and wild-type (WT) mice suffered comparable HI brain damage.
View Article and Find Full Text PDFThe preclinical selection of therapeutic candidates for progressive multiple sclerosis (MS) would be aided by the development of sensitive behavioural measures that accurately reflect the impact of autoimmune-mediated spinal cord damage on locomotion. Neurological deficits in mice subjected to experimental autoimmune encephalomyelitis (EAE) are typically scored using a clinical scale with 5-10 levels of increased disease severity. This ordinal scale represents a general impression of paralysis and impaired gait.
View Article and Find Full Text PDFCalcium (Ca) plays diverse roles in all living organisms ranging from bacteria to humans. It is a structural element for bones, an essential mediator of excitation-contraction coupling, and a universal second messenger in the regulation of ion channel, enzyme and gene expression activities. In mitochondria, Ca is crucial for the control of energy production and cellular responses to metabolic stress.
View Article and Find Full Text PDFDisruption of sleep/wake cycles is common in patients with schizophrenia and correlates with cognitive and affective abnormalities. Mice deficient in stable tubule only polypeptide (STOP) show cognitive, behavioral, and neurobiological deficits that resemble those seen in patients with schizophrenia, but little is known about their sleep phenotype. We characterized baseline sleep/wake patterns and recovery sleep following sleep deprivation in STOP null mice.
View Article and Find Full Text PDFDeletion of the cellular inhibitor of apoptosis protein 2 (cIAP2) is capable of rendering lipopolysaccharide (LPS)-activated macrophages highly susceptible to apoptotic triggers, thereby quickly eliminating the resident macrophage population soon after the initiation of a systemic inflammatory response. The aim of our study was to evaluate the impact of cIAP2 deletion on leukocyte recruitment and capillary perfusion in experimental endotoxemia and polybacterial sepsis using intravital microscopy of the intestinal microcirculation, which is crucial in the pathogenesis of septic multiple organ failure. We studied six groups of animals: wild-type (WT) control mice, cIAP2 knockout mice, endotoxemic WT mice (5 mg/kg LPS), endotoxemic cIAP2 knockouts (5 or 50 mg/kg LPS, respectively), and WT as well as knockout mice with polybacterial sepsis (colon ascendens stent peritonitis [CASP]).
View Article and Find Full Text PDFJ Neuroimmunol
March 2014
The anti-inflammatory and restorative effects of the flavonoid-enriched fraction AF4 were examined in a mouse model of experimental autoimmune encephalomyelitis (EAE). Relative to EAE mice that received vehicle (water, 10 ml/kg/day), oral administration of AF4 (25mg/kg/day) beginning 24h after the onset of clinical signs reduced disease severity from days 19-31 post-immunization. AF4-mediated recovery from EAE was preceded by reduced plasma concentrations of TNFα and IL-1β on day 18 followed by decreased cytokine production and neuropathology in the cerebellum and spinal cord on day 31.
View Article and Find Full Text PDFTranscriptional dysregulation is a major pathological feature of Huntington's disease (HD). The goal of this study was to understand how p65/RelA co-regulated genes, specifically those of the cytokine and endocannabinoid systems, were affected in HD. p65/RelA levels were lower in human HD tissue and R6/2 HD mice, as were the levels of the type 1 cannabinoid receptor (CB1), IL-1β, IL-8, CCL5, GM-CSF, MIP-1β, and TNFα, all of which may be regulated by p65/RelA.
View Article and Find Full Text PDFX-linked inhibitor of apoptosis (XIAP) protects and preserves the function of neurons in both in vitro and in vivo models of excitotoxicity. Since calcium (Ca(2+)) overload is a pivotal event in excitotoxic neuronal cell death, we have determined whether XIAP over-expression influences Ca(2+)-signaling in primary cultures of mouse cortical neurons. Using cortical neuron cultures derived from wild-type (Wt) mice transiently transfected with XIAP or from transgenic mice that over-express XIAP, we show that XIAP opposes the rise in intracellular Ca(2+) concentration by a variety of triggers.
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