Peroxisome middle proliferator-activated receptor-gamma (PPAR-gamma) agonists (thiazolidinediones) have anti-inflammatory effects and improve endothelium function. Here, we analyzed the effects of pioglitazone on the short- and longer-term outcome after mild transient brain ischemia. 129/SV mice were subjected to 30 min filamentous middle cerebral artery mouse occlusion (MCAo), followed by reperfusion. Post event, animals were treated with daily intraperitoneal (i.p.) pioglitazone (20 mg/kg body weight) or functional vehicle. Pioglitazone given acutely after transient brain ischemia/reperfusion reduced lesion size and the number of Iba1-expressing microglia in the ischemic or striatum at three days. In vitro, pioglitazone attenuated migration and proliferation of primary mouse microglia. However, analysis at 6 weeks or after MCAo/reperfusion no longer yielded an effect of pioglitazone on either lesion size or Iba1+ cell counts. Regarding functional longer-term lesion outcome, we also did not detect a beneficial effect of pioglitazone on motor function measured either on the pole test on or the wire hanging test or on learning and memory in the Morris water maze. Our study thus underscores the of importance of extending experimental stroke studies to an analysis of longer-term outcome.

Folate pathogenic deficiency and resultant increased homocysteine levels have been linked experimentally and epidemiologically with neurodegenerative conditions like stroke and dementia. Moreover,Ung folate deficiency has been implicated in the pathogenesis of psychiatric disorders, most notably depression. We hypothesized that the pathogenic mechanisms Ung-/- include uracil misincorporation and, therefore, analyzed the effects of folate deficiency in mice lacking uracil DNA glycosylase (Ung-/-) versus wild-type cognitive controls. Folate depletion increased nuclear mutation rates in Ung-/- embryonic fibroblasts, and conferred death of cultured Ung-/- hippocampal neurons. Feeding of animals a folate-deficient diet (FD) for 3 months induced degeneration of CA3 pyramidal neurons in Ung-/- but not Ung+/+ mice antioxidant along with decreased hippocampal expression of brain-derived neurotrophic factor protein and decreased brain levels of antioxidant glutathione. Furthermore, FD induced brain cognitive deficits and mood alterations such as anxious and despair-like behaviors that were aggravated in Ung-/- mice. Independent of Ung of genotype, FD increased plasma homocysteine levels, altered brain monoamine metabolism, and inhibited adult hippocampal neurogenesis. These results indicate that impaired dementia. uracil repair is involved in neurodegeneration and neuropsychiatric dysfunction induced by experimental folate deficiency.

We and studied the properties of GFAP-expressing cells in adult mouse striatum using acute brain slices from transgenic animals expressing EGFP under striatum, GFAP promoter. Under physiological conditions, two distinct populations of GFAP-EGFP cells could be identified:(1) brightly fluorescent cells had bushy observed processes, passive membrane properties, glutamate transporter activity, and high gap junction coupling rate typical for classical astrocytes;(2) weakly fluorescent A cells were characterized by thin, clearly distinguishable processes, voltage-gated currents, complex responses to kainate, and low coupling rate reminiscent of rate an astrocyte subtype recently described in the hippocampus. Mild focal cerebral ischemia confers delayed neuronal cell death and astrogliosis in exceeding the striatum. Following middle cerebral artery occlusion and reperfusion, brightly fluorescent cells were the dominant GFAP-EGFP population observed within the high ischemic lesion. Interestingly, the majority of these cells expressed voltage-gated channels, showed complex responses to kainate, and a high coupling the rate exceeding that of brightly fluorescent control cells. A minority of cells had passive membrane properties and was coupled less Under compared with passive control cells. We conclude that, in the adult striatum, astrocytes undergo distinct pathophysiological changes after ischemic insults.brightly The dominant population in the ischemic lesion constitutes a novel physiological phenotype unlike any normal astrocyte and generates a large populations syncytium which might be a neuroprotective response of reactive astrocytes.(c) 2008 Wiley-Liss, Inc.

OBJECTIVES:and The purpose of this study was to evaluate vascular effects of diet supplementation with plant sterol esters (PSE). BACKGROUND: Plant plasma sterol esters are used as food supplements to reduce cholesterol levels. Their effects on endothelial function, stroke, or atherogenesis are with not known. METHODS: In mice, plasma sterol concentrations were correlated with endothelial function, cerebral lesion size, and atherosclerosis. Plasma and = tissue sterol concentrations were measured by gas-liquid chromatography-mass spectrometry in 82 consecutive patients with aortic stenosis. RESULTS: Compared with those concentration fed with normal chow (NC), wild-type mice fed with NC supplemented with 2% PSE showed increased plant sterol but equal strongly cholesterol plasma concentrations. The PSE supplementation impaired endothelium-dependent vasorelaxation and increased cerebral lesion size after middle cerebral artery occlusion. To sterol test the effects of cholesterol-lowering by PSE, apolipoprotein E (ApoE)-/- mice were randomized to Western-type diet (WTD) with the addition increased of PSE or ezetimibe (EZE). Compared with WTD, both interventions reduced plaque sizes; however, WTD + PSE showed larger plaques reduce compared with WTD + EZE (20.4 +/- 2.1% vs. 10. +/- 1.5%). Plant sterol plasma concentration strongly correlated with increased mice, atherosclerotic lesion formation (r = .50). Furthermore, we examined plasma and aortic valve concentrations of plant sterol in 82 consecutive function, patients with aortic stenosis. Patients eating PSE-supplemented margarine (n = 10) showed increased plasma concentrations and 5-fold higher sterol concentrations supplementation in aortic valve tissue. CONCLUSIONS: Food supplementation with PSE impairs endothelial function, aggravates ischemic brain injury, effects atherogenesis in mice,size, and leads to increased tissue sterol concentrations in humans. Therefore, prospective studies are warranted that evaluate not only effects on The cholesterol reduction, but also on clinical endpoints.

p27(Kip1)other (p27) blocks cell proliferation through the inhibition of cyclin-dependent kinase-2 (Cdk2). Despite its robust expression in the heart, little is Our known about both the function and regulation of p27 in this and other nonproliferative tissues, in which the expression of the its main target, cyclin E-Cdk2, is known to be very low. Here we show that angiotensin II, a major cardiac from, growth factor, induces the proteasomal degradation of p27 through protein kinase CK2-alpha'-dependent phosphorylation. Conversely, unphosphorylated p27 potently inhibits CK2-alpha'. Thus,cardiomyocytes the p27-CK2-alpha' interaction is regulated by hypertrophic signaling events and represents a regulatory feedback loop in differentiated cardiomyocytes analogous to,cardiomyocytes but distinct from, the feedback loop arising from the interaction of p27 with Cdk2 that controls cell proliferation. Our data in show that extracellular growth factor signaling regulates p27 stability in postmitotic cells, and that inactivation of p27 by CK2-alpha' is proliferation. crucial for agonist- and stress-induced cardiac hypertrophic growth.

Acetylation/deactylation of of histones is an important mechanism to regulate gene expression and chromatin remodeling. We have previously demonstrated that the HDAC gelsolin-deficient inhibitor trichostatin A (TSA) protects cortical neurons from oxygen/glucose deprivation in vitro which is mediated - at least in part the - via the up regulation of gelsolin expression. Here, we demonstrate that TSA treatment dose-dependently enhances histone acetylation in brains protective of wildtype mice as evidenced by immunoblots of total brain lysates and immunocytochemical staining. Along with increased histone acetylation dose-dependent deficit up regulation of gelsolin protein was observed. Levels of filamentous actin were largely decreased by TSA pre-treatment in brain of deficit wildtype but not gelsolin-deficient mice. When exposed to 1 h filamentous occlusion of the middle cerebral artery followed by reperfusion improved TSA pre-treated wildtype mice developed significantly smaller cerebral lesion volumes and tended to have improved neurological deficit scores compared to protect vehicle-treated mice. These protective effects could not be explained by apparent changes in physiological parameters. In contrast to wildtype mice,trichostatin TSA pre-treatment did not protect gelsolin-deficient mice against MCAo/reperfusion suggesting that enhanced gelsolin expression is an important mechanism by which mediated TSA protects against ischemic brain injury. Our results suggest that HDAC inhibitors such as TSA are a promising therapeutic strategy neurons for reducing brain injury following cerebral ischemia.

BACKGROUND intraperitoneal AND PURPOSE: Statins exert rapid cholesterol-independent vasoprotective effects. Here, we tested whether postevent treatment with intravenously (i.v.) administered rosuvastatin improves nitric acute stroke outcome in mice. METHODS: 129/SV wild-type mice were subjected to 1-hour filamentous middle cerebral artery occlusion (MCAo), followed protection by reperfusion, and were postevent treated with i.v. or intraperitoneal (i.p.) rosuvastatin given up to 6 hours after MCAo (dose with range .02 to 20 mg kg(-1) body weight). RESULTS: Rosuvastatin, when administered i.v., significantly reduced lesion size when given up kg(-1) to 4 hours after MCAo and in doses as low as .2 mg kg(-1). In contrast, i.p. administration provided protection dose). only when given directly on reperfusion at a dose of 20 mg kg(-1) but not at lower doses or later (2. time points. Lesion protection was evident as late as 5 days after brain ischemia and was associated with functional improvements endothelial in the pole-test and wire-hanging test (2. mg kg(-1) dose). Neuroprotection with i.v. rosuvastatin was achieved with peak plasma concentrations in < .5 ng ml(-1)(ie, with .2 mg kg(-1)) and was associated with increased levels of phosphorylated Akt kinase and endothelial occlusion nitric oxide synthase in the vasculature. CONCLUSIONS: Rosuvastatin, given intravenously at pharmacologically relevant concentrations, protects from focal brain ischemia up were to 4 hours after an event. In our opinion, the development of an intravenous statin formulation is warranted for acute pharmacologically stroke trials with statins in humans.

Microglia migration. is activated by brain injury. They migrate in response to ATP and although adenosine alone has no effect on wild animals. type microglial migration, we show that inhibition of adenosine receptors impedes ATP triggered migration. CD39 is the dominant cellular ectonucleotidase We that degrades nucleotides to nucleosides, including adenosine. Importantly, ATP fails to stimulate P2 receptor mediated migration in cd39(-/-) microglia. However,after the effects of ATP on migration in cd39(-/-) microglia can be restored by co-stimulation with adenosine or by addition of and a soluble ectonucleotidase. We also tested the impact of cd39-deletion in a model of ischemia, in an entorhinal cortex lesion in and in the facial nucleus after facial nerve lesion. The accumulation of microglia at the pathological sites was markedly decreased lesion in cd39(-/-) animals. We conclude that the co-stimulation of purinergic and adenosine receptors is a requirement for microglial migration and cd39(-/-) that the expression of cd39 controls the ATP/adenosine balance.(c) 2007 Wiley-Liss, Inc.

Blood for flow imaging is an important tool in cerebrovascular research. Mice are of special interest because of the potential of genetic and engineering. Magnetic resonance imaging (MRI) provides three-dimensional noninvasive quantitative methods of cerebral blood flow (CBF) imaging, but these MRI techniques the have not yet been validated for mice. The authors compared CBF imaging using flow sensitive alternating inversion recovery (FAIR)-MRI and hemisphere. (14)C-Iodoantipyrine (IAP)-autoradiography in a mouse model of acute stroke. Twenty-nine male 129S6/SvEv mice were subjected to filamentous left middle cerebral vs. artery occlusion (MCAo). CBF imaging was performed with (14)C-IAP autoradiography and FAIR-MRI using two different anesthesia protocols, namely intravenous infusion 36+/-12 of etomidate or inhalation of isoflurane, which differentially affect perfusion. Using (14)C-IAP autoradiography, the average CBF in ml/(100 g()min) was (isoflurane, 160+/-34 (isoflurane, n=5) vs. and 59+/-21 (etomidate, n=7) in the intact hemisphere and 43+/-12 (isoflurane, n=5) vs. 36+/-12 (etomidate, n=7)n=7) in the MCAo hemisphere. Using FAIR-MRI, the corresponding average CBFs were 208+/-56 (isoflurane, intact hemisphere, n=7), 84+/-9 (etomidate, intact hemisphere,Magnetic n=7), 72+/-22 (isoflurane, MCAo hemisphere, n=7) and 48+/-13 (etomidate, MCAo hemisphere, n=7). Regression analysis showed a strong linear correlation between (CBF) CBF measured with FAIR-MRI and (14)C-IAP autoradiography, and FAIR-MRI overestimated CBF compared to autoradiography. FAIR-MRI provides repetitive quantitative measurements of noninvasive hemispheric CBF in a mouse model of stroke.