57 research outputs found

    Cerebral ischemic damage in diabetes: an inflammatory perspective

    Get PDF

    Long-term soluble Abeta(1-40) activates CaM kinase II in organotypic hippocampal cultures

    No full text
    Recent findings suggested a role for soluble amyloid-beta (Abeta) peptides in Alzheimer's disease associated cognitive decline. We investigated the action of soluble, monomeric Abeta(1-40) on CaM kinase II, a kinase involved in neuroplasticity and cognition. We treated organotypic hippocampal cultures short-term (up to 4h) and long-term (5 days) with Abeta(1-40) (1nM-5muM). Abeta did not induce cell damage, apoptosis or synaptic loss. Short-term treatment down-regulated enzymatic activity of the kinase, by reducing its Thr(286) phosphorylation. In contrast, long-term treatment (1nM-5muM) markedly and significantly up-regulated enzymatic activity, with peak stimulation at 10nM (three-fold). Up-regulation of activity was associated with increased expression of the alpha-isoform of CaM kinase II, increased phosphorylation at Thr(286) (activator residue) and decreased phosphorylation at Thr(305-306) (inhibitory residues). We investigated the effect of glutamate on CaM kinase II following exposure to 1 or 10nM Abeta(1-40). As previously reported, glutamate increased CaM kinase II activity. However, the glutamate effect was not altered by pretreatment of slices with Abeta. Short- and long-term Abeta treatment showed opposite effects on CaM kinase II, suggesting that long-term changes are an adaptation to the kinase early down-regulation. The marked effect of Abeta(1-40) on the kinase suggests that semi-physiological and slowly raising peptide concentrations may have a significant impact on synaptic plasticity in the absence of synaptic loss or neuronal cell death

    Long-lasting protection in brain trauma by endotoxin preconditioning

    No full text
    We investigated the occurrence of endotoxin (lipopolysaccharide, LPS) preconditioning in traumatic brain injury (TBI), evaluating the time window of LPS-induced protection, its persistence, and the associated molecular mechanisms. Mice received 0.1\u2009mg/kg LPS or saline intraperitoneally and subsequently TBI (by controlled cortical impact brain injury) at various time intervals. Mice receiving LPS 3, 5, or 7 days before TBI showed attenuated motor deficits at 1 week after injury compared with mice receiving saline. Those receiving LPS 5 days before injury had also a reduced contusion volume (7.9\ub11.3 versus 12\ub12.3\u2009mm(3)) and decreased cell death. One month after injury, the protective effect of LPS on contusion volume (14.5\ub11.2 versus 18.2\ub11.2\u2009mm(3)) and neurologic function was still present. Traumatic brain injury increased glial fibrillary acidic protein, CD11b, CD68, tumor necrosis factor-\u3b1, interleukin (IL)-10, and IL-6 mRNA expression 24\u2009hours after injury. Lipopolysaccharide administered 5 (but not 9) days before injury increased the expression of CD11b (233%) and of interferon \u3b2 (500%) in uninjured mice, while it reduced the expression of CD68 (by 46%) and increased that of IL-6 (by 52%) in injured mice. Lipopolysaccharide preconditioning conferred a long-lasting neuroprotection after TBI, which was associated with a modulation of microglia/macrophages activity and cytokine productio

    Dilated cardiomyopathy presenting in childhood: aetiology, diagnostic approach, and clinical course.

    No full text
    Abstract OBJECTIVE: To determine the outcome of dilated cardiomyopathy presenting in childhood and the features that might be useful for prognostic stratification. METHODS: Retrospective study of 41 consecutive children affected by dilated cardiomyopathy - aged 0-14 years; median 33.4 plus or minus 49.25 - between 1993 and 2008. We reviewed the medical history to determine age at diagnosis, family history, previous viral illness, aetiology, symptoms and signs at presentation, treatment, and outcome. The diagnosis was made on the basis of cardiomegaly and evidence of poor left ventricular function by echocardiography. We also carried out a metabolic evaluation including blood lactate, pyruvate, carnitine, amino acids, urine organic acids, assessment of respiratory chain enzymes, and analysis of histopathological material. Survival curves were constructed by the Kaplan-Meier method. RESULTS: Follow-up ranged from 10 days to 162 months - median 45.25 plus or minus 41.15 months. Freedom from death or cardiac transplantation was 68.3% at 5 years. The primary end-point of death/cardiac transplantation was associated with the need for intravenous inotropic support. A trend towards a poorer prognosis was found for age at diagnosis of more than 5 years and for a metabolic aetiology of dilated cardiomyopathy. For the children affected by cardiomyopathy as part of a multi-system involvement, mortality was 50%. CONCLUSIONS: In children, dilated cardiomyopathy is a diverse disorder with outcomes that depend on cause, age, and cardiac failure status at presentation. Overt cardiac failure at presentation is a major prognostic factor for death or cardiac transplantation. Older age at presentation and metabolic aetiology may be associated with a poorer prognosi
    corecore