scholarly journals Agmatine Attenuates Brain Edema through Reducing the Expression of Aquaporin-1 after Cerebral Ischemia

2009 ◽  
Vol 30 (5) ◽  
pp. 943-949 ◽  
Author(s):  
Jae Hwan Kim ◽  
Yong Woo Lee ◽  
Kyung Ah Park ◽  
Won Taek Lee ◽  
Jong Eun Lee

Brain edema is frequently shown after cerebral ischemia. It is an expansion of brain volume because of increasing water content in brain. It causes to increase mortality after stroke. Agmatine, formed by the decarboxylation of L-arginine by arginine decarboxylase, has been shown to be neuroprotective in trauma and ischemia models. The purpose of this study was to investigate the effect of agmatine for brain edema in ischemic brain damage and to evaluate the expression of aquaporins (AQPs). Results showed that agmatine significantly reduced brain swelling volume 22 h after 2 h middle cerebral artery occlusion in mice. Water content in brain tissue was clearly decreased 24 h after ischemic injury by agmatine treatment. Blood–brain barrier (BBB) disruption was diminished with agmatine than without. The expressions of AQPs-1 and -9 were well correlated with brain edema as water channels, were significantly decreased by agmatine treatment. It can thus be suggested that agmatine could attenuate brain edema by limitting BBB disruption and blocking the accumulation of brain water content through lessening the expression of AQP-1 after cerebral ischemia.

2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Mei-hong Shen ◽  
Chun-bing Zhang ◽  
Jia-hui Zhang ◽  
Peng-fei Li

Electroacupuncture (EA) has several properties such as antioxidant, antiapoptosis, and anti-inflammatory properties. The current study was to investigate the effects of EA on the prevention and treatment of cerebral ischemia-reperfusion (I/R) injury and to elucidate possible molecular mechanisms. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h followed by reperfusion for 24 h. EA stimulation was applied to bothBaihuiandDazhuiacupoints for 30 min in each rat per day for 5 successive days before MCAO (pretreatment) or when the reperfusion was initiated (treatment). Neurologic deficit scores, infarction volumes, brain water content, and neuronal apoptosis were evaluated. The expressions of related inflammatory cytokines, apoptotic molecules, antioxidant systems, and excitotoxic receptors in the brain were also investigated. Results showed that both EA pretreatment and treatment significantly reduced infarct volumes, decreased brain water content, and alleviated neuronal injury in MCAO rats. Notably, EA exerts neuroprotection against I/R injury through improving neurological function, attenuating the inflammation cytokines, upregulating antioxidant systems, and reducing the excitotoxicity. This study provides a better understanding of the molecular mechanism underlying the traditional use of EA.


F1000Research ◽  
2017 ◽  
Vol 6 ◽  
pp. 1827 ◽  
Author(s):  
Julius V. Emmrich ◽  
Jonas J. Neher ◽  
Philipp Boehm-Sturm ◽  
Matthias Endres ◽  
Ulrich Dirnagl ◽  
...  

Stroke is a major cause of death and disability worldwide. In addition to neuronal death resulting directly from energy depletion due to lack of blood supply, inflammation and microglial activation following ischemic brain injury has been increasingly recognized to be a key contributor to the pathophysiology of cerebrovascular disease. However, our understanding of the cross talk between the ischemic brain and the immune system is limited. Recently, we demonstrated that following focal ischemia, death of mature viable neurons can be executed through phagocytosis by microglial cells or recruited macrophages, i.e. through phagoptosis. It was shown that inhibition of phagocytic signaling pathways following endothelin-1 induced focal cerebral ischemia leads to increased neuronal survival and neurological recovery. This suggests that inhibition of specific phagocytic pathways may prevent neuronal death during cerebral ischemia. To further explore this potential therapeutic target, we propose to assess the role of phagocytosis in an established model of temporary (45min) middle cerebral artery occlusion, and to evaluate neuronal survival and neurological recovery in mice with deficient phagocytosis.


2009 ◽  
Vol 37 (02) ◽  
pp. 273-293 ◽  
Author(s):  
Youngjoo Sohn ◽  
Ho Chang Kang ◽  
Kon Sik Kim ◽  
Sun-Min Park ◽  
Nak-Won Sohn ◽  
...  

This study examined the effect of Natrii sulfas, a treatment for stroke patients suffering constipation in Oriental medicine, on the physiological indices and brain edema of rats. Brain edema was induced by a middle cerebral artery occlusion (MCAO), Natrii sulfas was administered after the MCAO. At 3, 6, 15, 24, and 48 hours after reperfusion, the physiological indices such as the fecal weight, urine volume and water content in the stools were assessed. The edema index was measured 48 hours after reperfusion. At 48 hours, the expressions of iNOS, MMP9, VEGF, GFAP, Bax, Bcl-2, c-Fos, and HSP72 positive astrocytes were observed on the brain tissues by immunohistochemistry. Natrii sulfas significantly improved the decrease in fecal weight, urine volume and water content in the stool caused by the ischemic insult (p < 0.05) and attenuated the brain edema caused by the ischemia insult (p < 0.05). Natrii sulfas significantly down-regulated iNOS and MMP9 expressions and attenuated the astrocyte swelling due to brain edema in the penumbra of the cerebral cortex of MCAO rats. Natrii sulfas reduced the excess Bax and HSP72 expressions in ischemic brain, which was statistically significant in the penumbra of the cerebral cortex but not in the caudate putamen. These results suggest Natrii sulfas has a protective effect on ischemia-induced brain edema and improves the physiological symptoms.


2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Lin Lu ◽  
Hui-qin Li ◽  
Ji-huang Li ◽  
Ai-ju Liu ◽  
Guo-qing Zheng

Sanhua decoction (SHD) is a famous classic Chinese herbal prescription for ischemic stroke, and aquaporin 4 (AQP4) is reported to play a key role in ischemic brain edema. This study aimed to investigate neuroprotection of SHD against focal cerebral ischemia/reperfusion (I/R) injury in rats and explore the hypothesis that AQP4 probably is the target of SHD neuroprotection against I/R rats. Lentiviral-mediated AQP4-siRNA was inducted into adult male Sprague-Dawley rats via intracerebroventricular injection. The focal cerebral ischemia/reperfusion model was established by occluding middle cerebral artery. Neurological examinations were performed according to Longa Scale. Brain water content, was determined by wet and dry weight measurement. Western blot was adopted to test the AQP4 expression in ipsilateral hippocampus. After the treatment, SHD alleviated neurological deficits, reduced brain water content and downregulated the expression of AQP4 at different time points following I/R injury. Furthermore, neurobehavioral function and brain edema after I/R were significantly attenuated via downregulation of AQP4 expression when combined with AQP4-siRNA technology. In conclusion, SHD exerted neuroprotection against focal cerebral I/R injury in rats mainly through a mechanism targeting AQP4.


Radiology ◽  
2007 ◽  
Vol 243 (3) ◽  
pp. 720-726 ◽  
Author(s):  
Imanuel Dzialowski ◽  
Ernst Klotz ◽  
Sophia Goericke ◽  
Arnd Doerfler ◽  
Michael Forsting ◽  
...  

1997 ◽  
Vol 17 (6) ◽  
pp. 597-604 ◽  
Author(s):  
R. Paul Stroemer ◽  
Nancy J. Rothwell

Interleukin-1 (IL-1) receptor antagonist (IL-1ra) markedly reduces infarct volume induced by middle cerebral artery occlusion (MCAO) in the rat, when injected either centrally (intracerebroventricularly) or peripherally. The site or sites of action of IL-1 in stroke pathology, however, are not known. The present study investigated the site(s) of action of IL-1/IL-1ra in ischemic brain damage by studying the effects of local injection of IL-1ra into the cortex or striatum following permanent MCAO in the rat. Cortical injection of IL-1ra (5 µg) did not affect infarct volume in the cortex or striatum measured 24 h after MCAO. In contrast, striatal injection of IL-1ra ipsilateral to the infarction caused a significant and highly reproducible reduction of cortical (37%, p < 0.001) and striatal damage (27%, p < 0.001, corrected for edema) compared with vehicle-injected animals. Injection of IL-1ra (5 µg) into the striatum, contralateral to the infarction, resulted in a small (9%) but significant (p < 0.001) reduction of ipsilateral cortical damage, with no effect on ipsilateral striatal damage. Injection of a higher dose of IL-1ra (7.5 µg) in the contralateral striatum caused a further inhibition of ipsilateral cortical damage (24%, p < 0.001) and a significant reduction of ipsilateral striatal damage (16%, p < 0.001). In separate groups of rats, it was established that core temperature (measured continuously in free-moving animals with remote radiotelemetry) was not affected by striatal or cortical injection of IL-1ra. These data show that injection of IL-1ra into the striatum but not the cortex reduces infarct volume in both the striatum and the cortex, independently of effects on core temperature. These results imply that blocking striatal IL-1 contributes to IL-1ra-protective effects. We hypothesize that IL-1 may influence striatal distal cortical damage through either the release of specific substances or activation of polysynaptic pathways.


F1000Research ◽  
2017 ◽  
Vol 6 ◽  
pp. 1827
Author(s):  
Julius V. Emmrich ◽  
Jonas J. Neher ◽  
Philipp Boehm-Sturm ◽  
Matthias Endres ◽  
Ulrich Dirnagl ◽  
...  

Stroke is a major cause of death and disability worldwide. In addition to neuronal death resulting directly from energy depletion due to lack of blood supply, inflammation and microglial activation following ischemic brain injury has been increasingly recognized to be a key contributor to the pathophysiology of cerebrovascular disease. However, our understanding of the cross talk between the ischemic brain and the immune system is limited. Recently, we demonstrated that following focal ischemia, death of mature viable neurons can be executed through phagocytosis by microglial cells or recruited macrophages, i.e. through phagoptosis. It was shown that inhibition of phagocytic signaling pathways following endothelin-1 induced focal cerebral ischemia leads to increased neuronal survival and neurological recovery. This suggests that inhibition of specific phagocytic pathways may prevent neuronal death during cerebral ischemia. To further explore this potential therapeutic target, we propose to assess the role of phagocytosis in an established model of temporary (45min) middle cerebral artery occlusion (tMCAo), and to evaluate neuronal survival and neurological recovery in mice with deficient phagocytosis. The primary outcome of this study will be forelimb function assessed with the staircase test. Secondary outcomes constitute Rotarod performance, stroke volume (quantified on MR imaging or brain sections, respectively), diffusion tensor imaging (DTI) connectome mapping, and histological analyses to measure neuronal and microglial densities, and phagocytic activity. Male mice aged 10-12 weeks will be used for experiments.


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