scholarly journals Lipocortin-1 is an endogenous inhibitor of ischemic damage in the rat brain.

1991 ◽  
Vol 174 (2) ◽  
pp. 305-310 ◽  
Author(s):  
J K Relton ◽  
P J Strijbos ◽  
C T O'Shaughnessy ◽  
F Carey ◽  
R A Forder ◽  
...  

Lipocortin-1 (annexin-1) is an endogenous peptide with antiinflammatory properties. We have previously demonstrated lipocortin immunoreactivity in certain glial cells and neurons in the rat brain (Strijbos, P.J.L.M., F.J.H. Tilders, F. Carey, R. Forder, and N.J. Rothwell. 1990. Brain Res. In press.), and have shown that an NH2-terminal fragment (1-188) of lipocortin-1 inhibits the central and peripheral actions of cytokines on fever and thermogenesis in the rat in vivo (Carey, F., R. Forder, M.D. Edge, A.R. Greene, M.A. Horan, P.J.L.M. Strijbos, and N.J. Rothwell. 1990. Am. J. Physiol. 259:R266; and Strijbos, P.J.L.M., J.L. Browning, M. Ward, R. Forder, F. Carey, M.A. Horan, and N.J. Rothwell. 1991. Br. J. Pharmacol. In press.). We now report that intracerebroventricular administration of lipocortin-1 fragment causes marked inhibition of infarct size (60%) and cerebral edema (46%) measured 2 h after cerebral ischemia (middle cerebral artery occlusion) in the rat in vivo. The lipocortin-1 fragment was effective when administered 10 min after induction of ischemia. Ischemia caused increased expression of lipocortin-1 around the area of infarction as demonstrated by immunocytochemistry. Intracerebroventricular injection of neutralizing antilipocortin-1 fragment antiserum increased the size of infarct (53%) and the development of edema (29%). These findings indicate that lipocortin-1 is an endogenous inhibitor of cerebral ischemia with considerable therapeutic potential.

2004 ◽  
Vol 24 (6) ◽  
pp. 668-676 ◽  
Author(s):  
Hiroharu Kataoka ◽  
Seong-Woong Kim ◽  
Nikolaus Plesnila

The contribution of leukocyte infiltration to brain damage after permanent focal cerebral ischemia and the underlying molecular mechanisms are still unclear. Therefore, the aim of this study was to establish a mouse model for the visualization of leukocytes in the cerebral microcirculation in vivo and to investigate leukocyte-endothelial interaction (LEI) after permanent middle cerebral artery occlusion (MCAO). Sham-operated 129/Sv mice showed physiologic LEI in pial venules as observed by intravital fluorescent microscopy. Permanent focal cerebral ischemia induced a significant increase of LEI predominantly in pial venules. The number of rolling and adherent leukocytes reached 36.5 ± 13.2/100 μm × min and 22.5 ± 7.9/100 μm × min, respectively at 120 minutes after MCAO ( P = 0.016 vs. control). Of note, rolling and adherent leukocytes were also observed in arterioles of ischemic animals (7.3 ± 3.0/100 μm × min rolling and 3.0 ± 3.6/100 μm × min adherent). Capillary density was not different between groups. These results demonstrate that leukocytes accumulate in the brain not only after transient but also after permanent focal cerebral ischemia and may therefore contribute to brain damage after stroke without reperfusion.


2005 ◽  
Vol 25 (1) ◽  
pp. 30-40 ◽  
Author(s):  
Wen Zhang ◽  
Ioana Potrovita ◽  
Victoria Tarabin ◽  
Oliver Herrmann ◽  
Verena Beer ◽  
...  

The transcription factor NF-κB is a key regulator of inflammation and cell survival. NF-κB is activated by cerebral ischemia in neurons and glia, but its function is controversial. To inhibit NF-κB selectively in neurons and glial cells, we have generated transgenic mice that express the IκBα superrepressor (IκBα mutated at serine-32 and serine-36, IκBα-SR) under transcriptional control of the neuron-specific enolase (NSE) and the glial fibrillary acidic protein (GFAP) promoter, respectively. In primary cortical neurons of NSE-IκBα-SR mice, NF-κB activity was partially inhibited. To assess NF-κB activity in vivo after permanent middle cerebral artery occlusion (MCAO), we measured the expression of NF-κB target genes by real-time polymerase chain reaction (PCR). The induction of c-myc and transforming growth factor-β2 by cerebral ischemia was inhibited by neuronal expression of IκBα-SR, whereas induction of GFAP by MCAO was reduced by astrocytic expression of IκBα-SR. Neuronal, but not astrocytic, expression of the NF-κB inhibitor reduced both infarct size and cell death 48 hours after permanent MCAO. In summary, the data show that NF-κB is activated in neurons and astrocytes during cerebral ischemia and that NF-κB activation in neurons contributes to the ischemic damage.


1982 ◽  
Vol 56 (5) ◽  
pp. 685-690 ◽  
Author(s):  
Warren R. Selman ◽  
Robert F. Spetzler ◽  
Richard A. Roski ◽  
Uros Roessmann ◽  
Ralph Crumrine ◽  
...  

✓ The therapeutic application of barbiturate-induced coma was evaluated in a primate model of focal cerebral ischemia. A standardized regimen of pentobarbital was used, and the times of initiation of administration were varied following a 6-hour middle cerebral artery occlusion in baboons. Three groups of five animals were treated at 30, 120, and 240 minutes after occlusion, while one group of five animals received no barbiturate therapy. Complete protection from intracranial pressure (ICP) elevation and ischemic damage was seen only in the group treated at 30 minutes. Those treated at 120 minutes, while doing better than untreated animals, still had ICP elevation and a marked neuropathological deficit. Animals treated at 240 minutes suffered a detrimental effect, in that malignant ICP and marked ischemic damage occurred earlier than in the untreated animals. The safe “therapeutic window” for barbiturate-induced coma in this animal model does not extend beyond 2 hours. Delayed administration results in a deleterious response and not merely a lack of protection.


2021 ◽  
Vol 12 ◽  
Author(s):  
Zhe Chen ◽  
Meng Gao ◽  
Yanlin Su ◽  
Pengran Liu ◽  
Binlei Sun

Ischemic stroke is caused by cerebral ischemia upon the blockage of an artery, which results in a high disability rate. Little is known regarding the mechanism of astrocyte function in cerebral ischemia. We aimed to determine the effects of running on the transformation of astrocytes, and subsequent synapse formation. A study of middle cerebral artery occlusion (MCAO) after running in vivo showed that running can promote the transformation of astrocytes toward the neuroprotective phenotype. Our findings of oxygen-glucose deprived astrocytes in vitro after running revealed that these astrocytes transformed into the neuroprotective phenotype, and that the expression of STAT3 and Gpc6 was increased. We confirmed that mechanistically, running can target Gpc6 through the STAT3 pathway and then regulate the number of synapses. We concluded that running promotes synapse proliferation by polarizing astrocytes toward the neuroprotective phenotype and ultimately leads to nerve regeneration.


2000 ◽  
Vol 20 (5) ◽  
pp. 765-771 ◽  
Author(s):  
Valerio Valeriani ◽  
Deborah Dewar ◽  
James McCulloch

Axons and oligodendrocytes are vulnerable to cerebral ischemia. The absence of quantitative methods for assessment of white matter pathology in ischemia has precluded in vivo evaluation of therapeutic interventions directed at axons and oligodendrocytes. The authors demonstrate here that the quantitative extent of white matter pathology was reduced by restoration of cerebral blood flow after 2 hours of middle cerebral artery occlusion. Focal ischemia was induced in anesthetized rats by intraluminal thread placement, either transiently (for 2 hours) or permanently. At 24 hours after induction of ischemia, axonal damage was determined by amyloid precursor protein (APP) immunohistochemistry, and the ischemic insult to oligodendrocytes was assessed by Tau-1 immunostaining in the same sections. In adjacent sections, ischemic damage to neuronal perikarya was defined histologically. The hemispheric extent of axonal damage was reduced by 70% in the transiently occluded animals from that in permanently occluded animals. The volumes of oligodendrocyte pathology and of neuronal perikaryal damage were reduced by 62% and 58%, respectively, in the transiently occluded animals. These results demonstrate that this methodologic approach for assessing ischemic damage in axons and oligodendrocytes can detect relative alterations in gray and white matter pathology with intervention strategies.


2014 ◽  
Vol 35 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Karin Hochrainer ◽  
Katherine Jackman ◽  
Corinne Benakis ◽  
Josef Anrather ◽  
Costantino Iadecola

Protein modifications cooperatively act to protect the proteome from cellular stress. Focal cerebral ischemia increases protein ubiquitination, resulting in formation of ubiquitin-rich aggregates. A concurrent elevation in small ubiquitin-related modifier (SUMO)-conjugated proteins has also been reported, but a potential connection to ubiquitin remains unexplored. Here we show that SUMO2/3 conjugates are present in postischemic ubiquitin-rich aggregates, physically associated with ubiquitin. The coaggregation of SUMO2/3 and ubiquitin is induced rapidly after ischemia, depends on reperfusion, and is also observed in the absence of ischemic damage. The association between SUMO and ubiquitin suggests overlapping functional roles after ischemia/reperfusion.


2005 ◽  
Vol 25 (1_suppl) ◽  
pp. S217-S217
Author(s):  
Kentaro Deguchi ◽  
Mikiro Takaishi ◽  
Takeshi Hayashi ◽  
Atsuhiko Oohira ◽  
Shoko Nagotani ◽  
...  

Human Cell ◽  
2021 ◽  
Author(s):  
Jiaying Zhu ◽  
Zhu Zhu ◽  
Yipin Ren ◽  
Yukang Dong ◽  
Yaqi Li ◽  
...  

AbstractLINGO-1 may be involved in the pathogenesis of cerebral ischemia. However, its biological function and underlying molecular mechanism in cerebral ischemia remain to be further defined. In our study, middle cerebral artery occlusion/reperfusion (MACO/R) mice model and HT22 cell oxygen–glucose deprivation/reperfusion (OGD/R) were established to simulate the pathological process of cerebral ischemia in vivo and in vitro and to detect the relevant mechanism. We found that LINGO-1 mRNA and protein were upregulated in mice and cell models. Down-regulation LINGO-1 improved the neurological symptoms and reduced pathological changes and the infarct size of the mice after MACO/R. In addition, LINGO-1 interference alleviated apoptosis and promoted cell proliferation in HT22 of OGD/R. Moreover, down-regulation of LINGO-1 proved to inhibit nuclear translocation of p-NF-κB and reduce the expression level of p-JAK2 and p-STAT3. In conclusion, our data suggest that shLINGO-1 attenuated ischemic injury by negatively regulating NF-KB and JAK2/STAT3 pathways, highlighting a novel therapeutic target for ischemic stroke.


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