scholarly journals Hypothermia selectively protects the anterior forebrain mesocircuit during global cerebral ischemia

2022 ◽  
Vol 17 (7) ◽  
pp. 1512
Author(s):  
Tian-Long Wang ◽  
Xiao-Hua Wang ◽  
Wei Jiang ◽  
Si-Yuan Zhang ◽  
Bin-Bin Nie ◽  
...  
Author(s):  
R.V.W. Dimlich ◽  
M.H. Biros

In severe cerebral ischemia, Purkinje cells of the cerebellum are one of the cell types most vulnerable to anoxic damage. In the partial (forebrain) global ischemic (PGI) model of the rat, Paljärvi noted at the light microscopic level that cerebellar damage is inconsistant and when present, milder than in the telencephalon, diencephalon and rostral brain stem. Cerebellar injury was observed in 3 of 4 PGI rats following 5 minutes of reperfusion but in none of the rats after 90 min of reperfusion. To evaluate a time between these two extremes (5 and 90 min), the present investigation used the PGI model to study the effects of ischemia on the ultrastructure of cerebellar Purkinje cells in rats that were sacrificed after 30 min of reperfusion. This time also was chosen because lactic acid that is thought to contribute to ischemic cell changes in PGI is at a maximum after 30 min of reperfusion.


Author(s):  
К.А. Никифорова ◽  
В.В. Александрин ◽  
П.О. Булгакова ◽  
А.В. Иванов ◽  
Э.Д. Вирюс ◽  
...  

Цель. Установить влияние неспецифического адреноблокатора карведилола на редокс-статус низкомолекулярных аминотиолов (цистеин, гомоцистеин, глутатион) в плазме крови при моделировании глобальной ишемии головного мозга у крыс. Методика. Нами была использована модель глобальной ишемии (пережатие общих сонных артерий с геморрагией длительностью 15 мин). Препарат вводили за 1 ч до операции. Уровни аминотиолов измеряли через 40 мин после начала реперфузии. Анализ уровня аминотиолов проводили методом жидкостной хроматографии. Результаты. Установлено, что у крыс, не подвергавшихся ишемии, карведилол в дозе 10 мг/кг вызывает рост редокс-статуса цистеина и глутатиона (в 3 и 3,5 раза соответственно по сравнению с контролем, p = 0,04 и p = 0,008) за счет увеличения их восстановленных форм. При ишемии данного эффекта не наблюдалось. Редокс-статус у крыс с ишемией на фоне карведилола (Цис = 0,85 ± 0,14%, Глн = 1,8 ± 0,7%, Гцис = 1,1 ± 0,8%) оставался таким же низким, как и у крыс с ишемией без введения карведилола (р > 0,8). Заключение. Полученный результат демонстрирует, что в условиях ишемии головного мозга карведилол не оказывает эффекта на гомеостаз аминотиолов плазмы крови, несмотря на выраженный антиоксидантный эффект в нормальных условиях. Aim. Effect of a nonspecific adrenergic antagonist carvedilol on the redox status of plasma low-molecular-weight aminothiols (cysteine, homocysteine, glutathione) was studied in rats with global cerebral ischemia (occlusion of common carotid arteries with hemorrhage). Methods. A model of global ischemia (occlusion of common carotid arteries with 15-min hemorrhage) was used. The drugs were administered one hour before the operation. Aminothiol levels were measured by HPLC with UV detection at 40 minutes after the onset of reperfusion. Results. Carvedilol 10 mg/kg increased the redox status of cysteine and glutathione in rats not exposed to ischemia (3 and 3.5 times, respectively, compared with the control, p = 0.04 and p = 0.008, respectively) but not of homocysteine, by increasing their reduced forms. However, this effect was not observed in ischemia. In rats with ischemia treated with carvedilol, the redox status (Cys = 0.85 ± 0.14%, GSH = 1.8 ± 0.7%, Hcys = 1.1 ± 0.8%) remained low similar to that in rats with ischemia not treated with carvedilol (p >0.8, 0.8, and 0.9, respectively). Conclusion. Carvedilol did not affect the homeostasis of blood plasma thiols in cerebral ischemia despite the pronounced antioxidant effect under the normal conditions.


Author(s):  
Amteshwar Singh Jaggi

Aim: The aim of the present study is to explore the neuroprotective effects of remote ischemic preconditioning in long term cognitive impairment after global cerebral ischemia induced-vascular dementia in mice. Material and methods: The mice were subjected to global cerebral ischemia by occluding the bilateral common carotid arteries for 12 minutes followed by the 24 hours of the reperfusion. The remote ischemic preconditioning stimulus was delivered in the form of 4 cycles of ischemia/reperfusion for 5 minutes each. The cerebral ischemic injury induced-long term cognitive impairment-related learning and memory alterations was assessed using morris water maze, the motor performances of the animals were evaluated using rota-rod test and neurological severity score. The cerebral infract size of the brain were quantified using triphenyltetrazolium chloride staining. Results: Global cerebral ischemia causes long term memory impairment, decreases motor performances and increases the brain infract size in animals. The delivery of remote ischemic preconditioning stimulus significantly abolished the long-term cognitive impairment and ameliorates the motor performances as well as cerebral infract size in brain. Conclusion: The remote ischemic preconditioning mediates neuro protection against global cerebral ischemic injury induced long-term cognitive impairment.


2012 ◽  
Vol 14 (1) ◽  
pp. 20-35 ◽  
Author(s):  
Jake T. Neumann ◽  
Charles H. Cohan ◽  
Kunjan R. Dave ◽  
Clinton B. Wright ◽  
Miguel A. Perez-Pinzon

2021 ◽  
Vol 113 ◽  
pp. 101941
Author(s):  
Takayuki Nakajima ◽  
Yuji Kunieda ◽  
Yusuke Takahashi ◽  
Yuki Tanaka ◽  
Tomohiro Kondo ◽  
...  

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Lixuan Zhan ◽  
Xiaomei Lu ◽  
Wensheng Xu ◽  
Weiwen Sun ◽  
En Xu

Abstract Background Our previous study indicated that hypoxic preconditioning reduced receptor interacting protein (RIP) 3-mediated necroptotic neuronal death in hippocampal CA1 of adult rats after transient global cerebral ischemia (tGCI). Although mixed lineage kinase domain-like (MLKL) has emerged as a crucial molecule for necroptosis induction downstream of RIP3, how MLKL executes necroptosis is not yet well understood. In this study, we aim to elucidate the molecular mechanism underlying hypoxic preconditioning that inactivates MLKL-dependent neuronal necroptosis after tGCI. Methods Transient global cerebral ischemia was induced by the four-vessel occlusion method. Twenty-four hours before ischemia, rats were exposed to systemic hypoxia with 8% O2 for 30 min. Western blotting was used to detect the expression of MLKL and interleukin-1 type 1 receptor (IL-1R1) in CA1. Immunoprecipitation was used to assess the interactions among IL-1R1, RIP3, and phosphorylated MLKL (p-MLKL). The concentration of intracellular free calcium ion (Ca2+) was measured using Fluo-4 AM. Silencing and overexpression studies were used to study the role of p-MLKL in tGCI-induced neuronal death. Results Hypoxic preconditioning decreased the phosphorylation of MLKL both in neurons and microglia of CA1 after tGCI. The knockdown of MLKL with siRNA decreased the expression of p-MLKL and exerted neuroprotective effects after tGCI, whereas treatment with lentiviral delivery of MLKL showed opposite results. Mechanistically, hypoxic preconditioning or MLKL siRNA attenuated the RIP3-p-MLKL interaction, reduced the plasma membrane translocation of p-MLKL, and blocked Ca2+ influx after tGCI. Furthermore, hypoxic preconditioning downregulated the expression of IL-1R1 in CA1 after tGCI. Additionally, neutralizing IL-1R1 with its antagonist disrupted the interaction between IL-1R1 and the necrosome, attenuated the expression and the plasma membrane translocation of p-MLKL, thus alleviating neuronal death after tGCI. Conclusions These data support that the inhibition of MLKL-dependent neuronal necroptosis through downregulating IL-1R1 contributes to neuroprotection of hypoxic preconditioning against tGCI.


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