Brain research
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Cerebral vasospasm (CV) is the main complication of spontaneous subarachnoid hemorrhage (SAH), affecting clinical outcome of patients with SAH. Accumulating evidence indicates that apolipoprotein E (apoE protein, APOE gene) gene polymorphism is associated with prognosis of patients with SAH. The current study aimed to investigate the association of promoter polymorphism of APOE with CV in patients with SAH. ⋯ Uni- and multivariate logistic regression analyses also showed that promoter -219T was a risk factor to predispose CV after SAH. However, there was no significant association between promoter -491A/T (rs#449647) or -427C/T (rs#769446) polymorphisms and SAH induced CV (P>0.05). Our finding suggests that patients with APOE -219T promoter are apt to CV after spontaneous SAH.
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Triptans, acting as serotonin, 5-HT(1B/1D/1F), receptor agonists, provide an effective and established treatment option in migraine and cluster headache. Clinical observations suggest a relatively specific effect of these compounds on primary headache disorders, but not in other pain syndromes. The mechanism of this specificity, however, is not well understood. ⋯ There was a good agreement for 5-HT(1B) and 5-HT(1D) receptors to that previously demonstrated in Vg and DRG L(5), while this was the first characterisation for 5-HT(1F) receptor in any of the five regions, as well as for 5-HT(1B) and 5HT(1D) receptors in DRG C(2), C(5) and T(5). In summary, all three 5-HT receptors are equally represented in Vg and the DRGs examined. We conclude that the triptans are theoretically able to bind to receptors at each level of the peripheral neuraxis without any apparent anatomical preference for the head.
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Astaxanthin (ATX), the most abundant flavonoids in propolis, has been proven to exert neuroprotective property against glutamate-induced neurotoxicity and ischemia-reperfusion-induced apoptosis. Previous study have revealed that ATX can rescue PC12 cells from Aβ(25-35)-induced apoptotic death. However, the mechanisms by which ATX mediates its therapeutic effects in vitro are unclear. ⋯ Because the inhibitor of HO-1 activity, ZnPP reversed the protective effect of ATX against Aβ(25-35)-induced cell death. We also demonstrated that the specific ERK inhibitor, PD98059, concentration-dependently blocked on ATX-induced HO-1 expression, and meanwhile PD98059 reversed the protective effect of ATX against Aβ25-35-induced cell death. Taken together, these findings suggest that astaxanthin can induce HO-1 expression through activation of ERK signal pathways, thereby protecting the SH-SY5Y cells from Aβ(25-35)-induced oxidative cell death.
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Rotenone, a mitochondrial complex 1 inhibitor, causes oxidative damage via production of reactive oxygen species. We examined the pathophysiology of neuronal and glial cells of the nigrostriatal pathway following unilateral infusion of varying doses of rotenone into the substantia nigra or medial forebrain bundle of adult male Sprague-Dawley rats, sacrificed 14 and 60 days after infusion. Immunofluorescence techniques were used to qualitatively and quantitatively assay dopaminergic neurons, their projections, glial cells, synapses, and oxidative stress. ⋯ The infusion of 0.5μg of rotenone also caused an increase in astrocytes and microglial cells in the substantia nigra in comparison to control (p≤0.01). We examined the time-dependent reduction of tyrosine hydroxylase-positive nerve fibres and cell bodies in the striatum and substantia nigra respectively, with a progressive reduction evident 60days after infusion (p≤0.01, p≤0.05). Dopaminergic axons exposed to low-dose rotenone undergo oxidative stress, with a resultant ongoing loss of dopaminergic neurons, providing an animal model relevant to Parkinson disease.
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Issues related to the intra-cerebral delivery of glial cell line-derived neurotrophic factor (GDNF) have hampered its progression as a neuroprotective therapy for Parkinson's disease. Ex vivo gene therapy, where cells are virally transduced in vitro to produce a specific protein, may circumvent some of the problems associated with direct delivery of this neurotrophin to the brain. In this regard, bone marrow-derived mesenchymal stem cells (MSCs) offer an ideal cell source for ex vivo gene therapy because they are easily isolated from autologous sources, they are amenable to viral transduction and expansion in vitro, and they are hypoimmunogenic and non-tumourigenic in the brain. ⋯ Rats received intrastriatal transplants of GDNF-transduced MSCs 4days prior to induction of an intrastriatal 6-hydroxydopamine lesion. Quantitative tyrosine hydroxylase immunohistochemical staining revealed that GDNF-transduced MSCs were capable of inducing a pronounced local trophic effect in the denervated striatum which was evident by sprouting from the remaining dopaminergic terminals towards the neurotrophic milieu created by the transplanted cells. This strengthens the candidacy of MSCs as vehicles to deliver neurotrophins to the Parkinsonian brain.