BACKGROUND:Recent studies have showed that S100A8 has been implicated in the pathobiology of inflammatory disorders,and that cerebral ischemia reperfusion(l/R) rapidly activates inflammation responses via Toll-like re...BACKGROUND:Recent studies have showed that S100A8 has been implicated in the pathobiology of inflammatory disorders,and that cerebral ischemia reperfusion(l/R) rapidly activates inflammation responses via Toll-like receptor 4(TLR4).This study aimed to explore the expression of S100A8 and the relationship between S100A8 and TLR4 in focal cerebral ischemia reperfusion injury.METHODS:C3H/HeJ mice(n=30) and C3H/HeN mice(n=30) were divided randomly into a C3H/HeJ model group(n=18),a C3H/HeJ control group(n=12),a C3H/HeN model group(n=18),and a C3H/HeN control group(n=12).Middle cerebral artery l/R model in mice was produced using a thread embolism method.The brains of the mice were collected after ischemia for 1 hour and reperfusion for 12 hours.Stroke outcome was evaluated by determination of infarct volume and assessment of neurological impairment scores.Brain injury after cerebral l/R was observed by an optical microscope after TTC and HE dyeing.The immunofluorescence technique and real time PCR were used to test the expression level of S100A8 in brain damage.RESULTS:Compared with C3H/HeN mice,TLR4-deficient mice(C3H/HeJ) had lower infarct volumes and better outcomes in neurological tests.The levels of S100A8 increased sharply in the brains of mice after l/R injury.In addition,mice that lacked TLR4(C3H/HeJ) had lower expression of l/R-induced S100A8 than C3H/HeN mice in the model group,indicating that a close relationship might exist between the levels of S100A8 and TLR4.CONCLUSION:S100A8 interaction with TLR4 might be involved in brain damage and in inflammation triggered by l/R injury.展开更多
BACKGROUND: The application of exogenous antioxidant is always the focus in the prevention and treatment of cerebral ischemia. Phycocyanin has the effects against oxidation and inflammation, but its role in the pathop...BACKGROUND: The application of exogenous antioxidant is always the focus in the prevention and treatment of cerebral ischemia. Phycocyanin has the effects against oxidation and inflammation, but its role in the pathophysiological process of cerebral ischemia reperfusion injury still needs further investigation. OBJECTIVE: To observe the effects of phycocyanin on the expression of superoxide dismutase (SOD), apoptosis and form of the nerve cells in rats after cerebral ischemia reperfusion injury. DESIGN: A randomized control animal experiment. SETTING: Institute of Cerebrovascular Disease, Medical School Hospital of Qingdao University. MATERIALS: Fifty-two healthy adult male Wistar rats of clean degree, weighing 220-260 g, were used. Phycocyanin was provided by the Institute of Oceanology, Chinese Academy of Sciences. METHODS: The experiments were carried out in Shangdong Key Laboratory for Prevention and Treatment of Brain Diseases from May to December 2005. ① All the rats were divided into three groups according to the method of random number table: sham-operated group (n=4), control group (n=24) and treatment group (n=24). Models of middle cerebral artery occlusion/reperfusion (MCAO/R) were established by the introduction of thread through external and internal carotid arteries in the control group and treatment group. After 1-hour ischemia and 2-hour reperfusion, rats in the treatment group were administrated with gastric perfusion of phycocyanin suspension (0.1 mg/g), and those in the control group were given saline of the same volume, and no treatment was given to the rats in the sham-operated group. ②The samples were removed and observed at ischemia for 1 hour and reperfusion for 6 and 12 hours and 1, 3, 7 and 14 days respectively in the control group and treatment group, 4 rats for each time point, and those were removed at 1 day postoperatively in the sham-operated group. Forms of the nerve cells were observed with toluidine blue staining. Apoptosis after cerebral ischemia reperfusion was detected with TUNEL technique. SOD expression was detected with immunohistochemical technique. ③ The intergroup difference was compared with the t test. MAIN OUTCOME MEASURES: The apoptosis of the nerve cells and SOD expression were mainly observed in each group. RESULTS: Finally, 52 rats were involved in the analysis of results. ① Number of apoptotic cells: In the sham-operated group, a few apoptotic cells could be observed in brain tissue. The apoptotic cells at each time point in the control group and treatment group were obviously more than those in the sham-operated group (P < 0.05). In the treatment group, the numbers of apoptotic cells at 12 hours, 1 and 3 days after reperfusion were significantly fewer than those in the control group, and those at 6 hours, 7 and 14 days were similar to those in the control group. ② Number of SOD positive cells: In the sham-operated group, there was weak expression of SOD in brain tissue, and the positive cells were extremely few, the positive cells at each time point were significantly more in the control group and treatment group than in the sham-operated group (P < 0.05). In the treatment group, the numbers of positive cells at 6 and 12 hours, 1 and 3 days after reperfusion were significantly fewer than those in the control group, and those at 7-14 days were similar to those in the control group. ③ Cellular forms: In the control group, the karyopyknosis occurred in the nerve cells, which were irregularly distributed, nucleolus disappeared, and some scattered cell fragments were observed. The forms of the nerve cells in the treatment group were generally normal. CONCLUSION: Phycocyanin plays a neuroprotective role in cerebral ischemia reperfusion injury by activating the SOD expression and inhibiting apoptosis.展开更多
Objective: To discuss the mechanism of low molecular weight GTP binding protein RAC1 in the injury of neural function based on building the rat model of cerebral ischemia reperfusion. Methods: Middle cerebral artery o...Objective: To discuss the mechanism of low molecular weight GTP binding protein RAC1 in the injury of neural function based on building the rat model of cerebral ischemia reperfusion. Methods: Middle cerebral artery of rats was ligated and the ligature was released to restore the perfusion after 2 h, the rat model of cerebral ischemia reperfusion injury was built, while the middle cerebral artery was ligated. The rats were randomly divided into the sham group, cerebral ischemia reperfusion group(I/R group) and the group with the injection of RAC1 activity inhibitor NSC23766(NSC group). The survival and neurological severity score of rats in each group were observed and recorded. Nissl staining was employed to observe the nerve cells, and Western blot to detect expression of RAC1, superoxide dismutase and malondialdehyde. Results: Number of nerve cells for rats in NSC group was significantly more than that in I/R group, but significantly less than that in sham group, with the statistical difference(P<0.05). The brain water content for rats in NSC group was significantly lower than that in I/R group, but significantly higher than that in sham group, with the statistical difference(P<0.05). The expression of RAC1 and malondialdehyde for rats in NSC group was significantly lower than that in I/R group, but higher than that in sham group; while the expression of superoxide dismutase was lower than that in sham group, but higher than that in I/R group, with the statistical difference(P<0.05). Conclusions: The inhibition of RAC1 activity can reduce the oxidative stress, reduce the neurologic impairment because of cerebral ischemia reperfusion and thus protect the neural function.展开更多
The aim of the present study was to investigate the effect of "nourishing liver and kidney" acupuncture therapy on motor and cognitive deficits,and the underlying mechanism following cerebral ischemia-reperf...The aim of the present study was to investigate the effect of "nourishing liver and kidney" acupuncture therapy on motor and cognitive deficits,and the underlying mechanism following cerebral ischemia-reperfusion(I/R) via increasing the expression of brain derived neurotrophic factor(BDNF) and synaptophysin(SYN) in the hippocampus.Healthy adult male SD rats were randomly divided into sham operation group(n=51),model group(n=51),acupuncture group(n=51) and acupuncture control group(n=51).The middle cerebral I/R model was established.Acupunctures were performed in the acupuncture group and acupuncture control group at acupoints of Taixi(K103),Taichong(ST09) of both sides,for 30 min once daily every morning.The animals in the sham operation group and model group were conventionally fed in the cage,without any intervention therapy.The rats of each group were assessed with modified neurological severity scores(m NSS).The expression of BDNF and SYN in the hippocampus was detected by immunohistochemical SP method and the synaptic structure in hippocampus area was assessed morphologically and quantitatively at the 3rd,7th and 14 th day.The Morris water Maze(MWM) test was used to evaluate the rats' learning and memory abilities on the 15 th day after acupuncture.The animals in the acupuncture control group and sham operation group presented no neurological deficit.In the acupuncture group,the nerve functional recovery was significantly better than that in the model group at the 7th and 14 th day after modeling.The average MWM escape latency in the acupuncture group was shorter than that in the model group at the 3rd,4th and 5th day.The number of crossings of the platform quadrant in the acupuncture group was significantly more than that in the model group.At the each time point,the expression levels of BDNF and SYN in the hippocampal regions increased significantly in the model group as compared with the sham operation group and the acupuncture control group.In the acupuncture group,the expression levels of BDNF at the 7th and 14 th day increased more significantly than those in the model group.In the acupuncture group,the expression levels of SYN at the each time point increased more significantly than those in the model group.The post-synaptic density(PSD) was significantly increased and the synapse cleft width was narrowed in the acupuncture group as compared with other groups.The synaptic curvatures were improved obviously in the acupuncture group in contrast to the model group.It was concluded that the "nourishing liver and kidney" acupuncture therapy has positive effects on behavioral recovery,as well as learning and memory abilities,probably by promoting the expression of BDNF and SYN,and synaptic structure reconstruction in the ipsilateral hippocampus after I/R in rats.The "nourishing liver and kidney" acupuncture therapy can promote the functional recovery in rats after cerebral ischemia injury.展开更多
Flavonoid glycoside scutellarin(SCU)has been widely applied in the treatment of cerebral ischemic diseases in China.In this article,we conducted research on the working mechanisms of SCU in hypoxia reoxygenation(HR)in...Flavonoid glycoside scutellarin(SCU)has been widely applied in the treatment of cerebral ischemic diseases in China.In this article,we conducted research on the working mechanisms of SCU in hypoxia reoxygenation(HR)injury of isolated cerebral basilar artery(BA)and erebral ischemia reperfusion(CIR)injury in rat models.In isolated rat BA rings,HR causes endothelial dysfunction(ED)and acetylcholine(ACh)induces endothelium-dependent vasodilation.The myography result showed that SCU(100μM)was able to significantly improve the endothelium-dependent vasodilation induced by Ach.However,SCU did not affect the ACh-induced relaxation in normal BA.Further studies suggested that SCU(10-1000μM)dose-dependently induced relaxation in isolated BA rings which were significantly blocked by the cGMP dependent protein kinase(PKG)inhibitor Rp-8-Br-cGMPs(PKGI-rp,4μM).Pre-incubation with SCU(500μM)reversed the impairment of endothelium-dependent vasodilation induced by HR,but the reversing effect was blocked if PKGI-rp(4μM)was added.The brain slice staining test in rats’model of middle cerebral artery occlusion(MCAO)induced CIR proved that the administration of SCU(45,90 mg/kg,iv)significantly reduced the area of cerebral infarction.The Western blot assay result showed that SCU(45 mg/kg,iv)increased brain PKG activity and PKG protein level after CIR surgery.In conclusion,our findings suggested that SCU possesses the ability of protecting brain cells against CIR injury through vascular endothelium protection and PKG signal.展开更多
Rutaecarpine,an active component of the traditional Chinese medicine Tetradium ruticarpum,has been shown to improve myocardial ischemia reperfusion injury.Because both cardiovascular and cerebrovascular diseases are f...Rutaecarpine,an active component of the traditional Chinese medicine Tetradium ruticarpum,has been shown to improve myocardial ischemia reperfusion injury.Because both cardiovascular and cerebrovascular diseases are forms of ischemic vascular disease,they are closely related.We hypothesized that rutaecarpine also has neuroprotective effects on cerebral ischemia reperfusion injury.A cerebral ischemia reperfusion model was established after 84,252 and 504 μg/kg rutaecarpine were given to mice via intraperitoneal injection,daily for 7 days.Results of the step through test,2,3,5-triphenyl tetrazolium chloride dyeing and oxidative stress indicators showed that rutaecarpine could improve learning and memory ability,neurological symptoms and reduce infarction volume and cerebral water content in mice with cerebral ischemia reperfusion injury.Rutaecarpine could significantly decrease the malondialdehyde content and increase the activities of superoxide dismutase and glutathione peroxidase in mouse brain.Therefore,rutaecarpine could improve neurological function following injury induced by cerebral ischemia reperfusion,and the mechanism of this improvement may be associated with oxidative stress.These results verify that rutaecarpine has neuroprotective effects on cerebral ischemia reperfusion in mice.展开更多
The present study investigated the effects of the mitochondrial calcium uniporter inhibitor ruthenium red and the agonist spermine on cerebral edema in rats with cerebral ischemia reperfusion injury. Left middle cereb...The present study investigated the effects of the mitochondrial calcium uniporter inhibitor ruthenium red and the agonist spermine on cerebral edema in rats with cerebral ischemia reperfusion injury. Left middle cerebral artery occlusion (MCAO) was induced in rats using the suture method. Following 24 hours of ischemic reperfusion, neurological function scores of rats with MCAO, and rats pretreated with ruthenium red and spermine were significantly lower, however, water content of brain tissue, aquaporin 4 expression and immunoglobulin G (IgG) exudation were significantly higher than those of sham-operated rats. Compared with MCAO rats and spermine-treated rats, neurological function scores were considerably higher, and brain tissue water content, aquaporin 4 expression and IgG exudation decreased in ruthenium red-treated rats. These findings suggest that preventive application of the mitochondrial calcium uniporter inhibitor ruthenium red can significantly decrease aquaporin 4 and IgG expression, influence the permeability of the blood brain barrier, and thereby decrease the extent of cerebral edema.展开更多
Netrin-1 is currently one of the most highly studied axon guidance factors. Netrin-1 is widely expressed in the embryonic central nervous system, and together with the deleted in colorectal cancer and uncoordinated lo...Netrin-1 is currently one of the most highly studied axon guidance factors. Netrin-1 is widely expressed in the embryonic central nervous system, and together with the deleted in colorectal cancer and uncoordinated locomotion-5 homolog B receptors, netrin-1 plays a guiding role in the construction of neural conduction pathways and the directional migration of neuronal cells. In this study, we established a rat middle cerebral artery ischemia reperfusion model using the intraluminal thread technique. Immunofluorescence microscopy showed that the expression of netrin-1 and deleted in colorectal cancer in the ischemic penumbra was upregulated at 1 day after reperfusion, reached a peak at 14 days, and decreased at 21 days. There was no obvious change in the expression of uncoordinated locomotion-5 homolog B during this time period. Double immunofluorescence labeling revealed that netrin-1 was expressed in neuronal cells and around small vessels, but not in astrocytes and microglia, while deleted in colorectal cancer was localized in the cell membranes and protrusions of neurons and astrocytes. Our experimental findings indicate that netrin-1 may be involved in post-ischemic repair and neuronal protection via deleted in colorectal cancer receptors.展开更多
AIBP has been gradually discovered and paid more and more attention.It is of great significance to explore the role of AIBP in cerebral ischemia-reperfusion injury and itse pathological mechanism.In this experiment,HT...AIBP has been gradually discovered and paid more and more attention.It is of great significance to explore the role of AIBP in cerebral ischemia-reperfusion injury and itse pathological mechanism.In this experiment,HT22 cells were divided into control group and experimental group.展开更多
Objective: To study the effects of resveratrol (Res) on regulating apoptosis and autophagy in cerebral ischemia reperfusion (I/R) in rats. Methods: SD rats were selected as experimental animals and randomly divided in...Objective: To study the effects of resveratrol (Res) on regulating apoptosis and autophagy in cerebral ischemia reperfusion (I/R) in rats. Methods: SD rats were selected as experimental animals and randomly divided into Sham group, I/R group and Res group. Sham group were given sham operation, I/R group were established into cerebral ischemia reperfusion models by suture method, and Res group were established into cerebral ischemia reperfusion models and then given resveratrol intervention. The protein levels of anti-apoptosis molecules, pro-apoptosis molecules and autophagy markers in brain tissues were measured 24 h after reperfusion. Results: Livin, Survivin, XIAP and p62 protein levels in brain tissue of I/R group were significantly lower than those of Sham group whereas CytC, AIF, Fas, FasL, Caspase-8, Caspase-9, LC3-Ⅱ, Beclin1, Bnip-3 and Atg5 protein levels were significantly higher than those of Sham group);Livin, Survivin, XIAP and p62 protein levels in brain tissue of Res group were significantly higher than those of I/R group whereas CytC, AIF, Fas, FasL, Caspase-8, Caspase-9, LC3-Ⅱ, Beclin1, Bnip-3 and Atg5 protein levels were significantly lower than those of I/R group. Conclusion: Resveratrol has a significant inhibitory effect on apoptosis and autophagy in cerebral ischemia reperfusion of rats.展开更多
Objective:To study the protective effect of levothyroxine on myocardial and cerebral ischemia reperfusion injury during surgery under cardiopulmonary bypass.Methods: Patients who underwent valve replacement under card...Objective:To study the protective effect of levothyroxine on myocardial and cerebral ischemia reperfusion injury during surgery under cardiopulmonary bypass.Methods: Patients who underwent valve replacement under cardiopulmonary bypass in Mianyang Central Hospital between March 2015 and December 2017 were selected and randomly divided into the Euthyrox group who received preoperative levothyroxine therapy and the control group who received routine preoperative intervention. The myocardial and cerebral injury indexes, pro-inflammatory and adhesion molecules as well as antioxidant indexes were measured before operation and 12 h after operation.Results: Twelve hours after operation, serum cTnI, LDH, CK-MB, H-FABP, NSE, S100B, CD11b/CD18, sP-selectin, IL-1 and IL-10 contents as well as SjvO2 levels of both groups were higher than those before operation whereas Cu-Zn SOD, CAT and GSH-Px contents were lower than those before operation, and serum cTnI, LDH, CK-MB, H-FABP, NSE, S100B, CD11b/CD18, sP-selectin, IL-1 and IL-10 contents as well as SjvO2 level of Euthyrox group were lower than those of control group whereas Cu-Zn SOD, CAT and GSH-Px contents were higher than those of control group.Conclusions:Levothyroxine has protective effect on the myocardial and cerebral ischemia reperfusion injury induced by inflammation and oxidative stress during surgery under cardiopulmonary bypass.展开更多
Objective: To study the effects of sevoflurane pretreatment on cerebral ischemia reperfusion injury in mice. Methods: C56 BL/6J mice were selected as experimental animals and divided into control group, I/R group and ...Objective: To study the effects of sevoflurane pretreatment on cerebral ischemia reperfusion injury in mice. Methods: C56 BL/6J mice were selected as experimental animals and divided into control group, I/R group and Sev group. I/R group and Sev group were established into cerebral ischemia reperfusion injury models through suture method, and Sev group were given consecutive 4 days of sevoflurane pretreatment before model establishment. The ischemia reperfusion brain tissue was collected to determine the mRNA expression of apoptosis genes and the levels of oxidative stress indexes. Results: Bcl-2, HAX-1, Mcl-1 and Survivin mRNA expression as well as Prdx6 and SOD levels in brain tissue of I/R group were significantly lower than those of control group whereas NF-kB, p53, Noxa, PTEN and Fas mRNA expression as well as Nox4, ROS and MDA levels were significantly higher than those of control group;Bcl-2, HAX-1, Mcl-1 and Survivin mRNA expression as well as Prdx6 and SOD levels in brain tissue of Sev group were significantly higher than those of I/R group whereas NF-kB, p53, Noxa, PTEN and Fas mRNA expression as well as Nox4, ROS and MDA levels were significantly lower than those of I/R group. Conclusion: Sevoflurane pretreatment can inhibit the apoptosis and oxidative stress response to alleviate the cerebral ischemia reperfusion injury in mice.展开更多
Objective:To study the effect of thyroid hormone (euthyrox) on myocardial and cerebral ischemia reperfusion injury in valve replacement under cardiopulmonary bypass.Methods:A total of 76 patients who received valve re...Objective:To study the effect of thyroid hormone (euthyrox) on myocardial and cerebral ischemia reperfusion injury in valve replacement under cardiopulmonary bypass.Methods:A total of 76 patients who received valve replacement under cardiopulmonary bypass in our hospital between January 2013 and December 2016 were collected and divided into control group (n=38) and observation group (n=38) according to random number table. Observation group took euthyrox orally 1 week before surgery, control group took vitamin C tablets orally at the same point in time, and both therapies lasted for 1 week. Before taking medicine and after cardiopulmonary bypass (before end of surgery), serum levels of myocardial enzyme spectrum indexes and nerve injury indexes were compared between the two groups of patients. Results: Before taking medicine, differences in the serum levels of myocardial enzyme spectrum indexes and nerve injury indexes were not statistically significant between the two groups of patients. After cardiopulmonary bypass, serum myocardial enzyme spectrum indexes cTnT, CK-MB,α-HBD and LDH levels in observation group were lower than those in control group;serum nerve injury indexes NSE, S100B and GFAP levels were lower than those in control group while bFGF level was higher than that in control group.Conclusion: Euthyrox intervention in valve replacement under cardiopulmonary bypass can effectively reduce the myocardial and cerebral ischemia reperfusion injury.展开更多
Objective:To study the influence and molecular mechanism of ticagrelor on cerebral ischemia reperfusion injury in rats.Methods:SD rats were selected as experimental animals and divided into control group, model group,...Objective:To study the influence and molecular mechanism of ticagrelor on cerebral ischemia reperfusion injury in rats.Methods:SD rats were selected as experimental animals and divided into control group, model group, ticagrelor group and clopidogrel group, cerebral ischemic reperfusion injury models were made, then ticagrelor group were given intragastric administration of 150 mg ticagrelor, clopidogrel group were given intragastric administration of 90 mg clopidogrel. 1 week after intervention, the brain water content as well as the contents of oxidative stress molecules and inflammatory factors were measured.Results: Water content in brain, MDA, Ox-LDL, NF-kB, TNF-α, IL-1β and IL-6 contents in brain tissue as well as TNF-α, IL-1β and IL-6 contents in serum of model group were significantly higher than those of control group while SOD, GSH-Px and Prdx6 contents in brain tissue were significantly lower than those of control group;water content in brain, MDA, Ox-LDL, NF-kB, TNF-α, IL-1β and IL-6 contents in brain tissue as well as TNF-α, IL-1β and IL-6 contents in serum of ticagrelor group and clopidogrel group were significantly lower than those of model group while SOD, GSH-Px and Prdx6 contents in brain tissue were significantly higher than those of model group;water content in brain, MDA, Ox-LDL, NF-kB, TNF-α, IL-1β and IL-6 contents in brain tissue as well as TNF-α, IL-1β and IL-6 contents in serum of ticagrelor group were significantly lower than those of clopidogrel group while SOD, GSH-Px and Prdx6 contents in brain tissue were significantly higher than those of clopidogrel group. Conclusion:Ticagrelor can be more effective in inhibiting oxidative stress response and inflammatory response, and reducing the cerebral ischemia reperfusion injury than clopidogrel.展开更多
β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unkno...β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic stroke.Here we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced apoptosis.Further investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic stroke.In addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its activity.In conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways.展开更多
Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury.Various calcium channels are involved in cerebral ischemia/reperfusion injury.Cav3.2 channel is a main subtype of T-type ...Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury.Various calcium channels are involved in cerebral ischemia/reperfusion injury.Cav3.2 channel is a main subtype of T-type calcium channels.T-type calcium channel blockers,such as pimozide and mibefradil,have been shown to prevent cerebral ischemia/reperfusion injury-induced brain injury.However,the role of Cav3.2 channels in cerebral ischemia/reperfusion injury remains unclear.Here,in vitro and in vivo models of cerebral ischemia/reperfusion injury were established using middle cerebral artery occlusion in mice and high glucose hypoxia/reoxygenation exposure in primary hippocampal neurons.The results showed that Cav3.2 expression was significantly upregulated in injured hippocampal tissue and primary hippocampal neurons.We further established a Cav3.2 gene-knockout mouse model of cerebral ischemia/reperfusion injury.Cav3.2 knockout markedly reduced infarct volume and brain water content,and alleviated neurological dysfunction after cerebral ischemia/reperfusion injury.Additionally,Cav3.2 knockout attenuated cerebral ischemia/reperfusion injury-induced oxidative stress,inflammatory response,and neuronal apoptosis.In the hippocampus of Cav3.2-knockout mice,calcineurin overexpression offset the beneficial effect of Cav3.2 knockout after cerebral ischemia/reperfusion injury.These findings suggest that the neuroprotective function of Cav3.2 knockout is mediated by calcineurin/nuclear factor of activated T cells 3 signaling.Findings from this study suggest that Cav3.2 could be a promising target for treatment of cerebral ischemia/reperfusion injury.展开更多
Studies have shown that C1q/tumor necrosis factor-related protein-6 (CTRP6) can alleviate renal ischemia/reperfusion injury in mice. However, its role in the brain remains poorly understood. To investigate the role of...Studies have shown that C1q/tumor necrosis factor-related protein-6 (CTRP6) can alleviate renal ischemia/reperfusion injury in mice. However, its role in the brain remains poorly understood. To investigate the role of CTRP6 in cerebral ischemia/reperfusion injury associated with diabetes mellitus, a diabetes mellitus mouse model of cerebral ischemia/reperfusion injury was established by occlusion of the middle cerebral artery. To overexpress CTRP6 in the brain, an adeno-associated virus carrying CTRP6 was injected into the lateral ventricle. The result was that oxygen injury and inflammation in brain tissue were clearly attenuated, and the number of neurons was greatly reduced. In vitro experiments showed that CTRP6 knockout exacerbated oxidative damage, inflammatory reaction, and apoptosis in cerebral cortical neurons in high glucose hypoxia-simulated diabetic cerebral ischemia/reperfusion injury. CTRP6 overexpression enhanced the sirtuin-1 signaling pathway in diabetic brains after ischemia/reperfusion injury. To investigate the mechanism underlying these effects, we examined mice with depletion of brain tissue-specific sirtuin-1. CTRP6-like protection was achieved by activating the sirtuin-1 signaling pathway. Taken together, these results indicate that CTRP6 likely attenuates cerebral ischemia/reperfusion injury through activation of the sirtuin-1 signaling pathway.展开更多
Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symp...Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symptoms are caused by numerous complex variant types of the circle.Additionally,the lack of an evaluation system for the cer-ebral ischemia/reperfusion(I/R)model of gerbils has shackled the application of this model.Methods:We created a symptom-oriented principle and detailed neurobehavioral scoring criteria.At different time points of reperfusion,we analyzed the alteration in locomotion by rotarod test and grip force score,infarct volume by triphenyltetrazo-lium chloride(TTC)staining,neuron loss using Nissl staining,and histological charac-teristics using hematoxylin-eosin(H&E)straining.Results:With a successful model rate of 56%,32 of the 57 gerbils operated by our method harbored typical features of cerebral I/R injury,and the mortality rate in the male gerbils was significantly higher than that in the female gerbils.The suc-cessfully prepared I/R gerbils demonstrated a significant reduction in motility and grip strength at 1 day after reperfusion;formed obvious infarction;exhibited typi-cal pathological features,such as tissue edema,neuronal atrophy and death,and vacuolated structures;and were partially recovered with the extension of reperfu-sion time.Conclusion:This study developed a new method for the unilateral common carotid artery ligation I/R model of gerbil and established a standardized evaluation system for this model,which could provide a new cerebral I/R model of gerbils with more practical applications.展开更多
Cerebral ischemia-reperfusion injury(CI/RI)remains the main cause of disability and death in stroke patients due to lack of effective therapeutic strategies.One of the main issues related to CI/RI treatment is the pre...Cerebral ischemia-reperfusion injury(CI/RI)remains the main cause of disability and death in stroke patients due to lack of effective therapeutic strategies.One of the main issues related to CI/RI treatment is the presence of the blood-brain barrier(BBB),which affects the intracerebral delivery of drugs.Ginkgolide B(GB),a major bioactive component in commercially available products of Ginkgo biloba,has been shown significance in CI/RI treatment by regulating inflammatory pathways,oxidative damage,and metabolic disturbance,and seems to be a candidate for stroke recovery.However,limited by its poor hydrophilicity and lipophilicity,the development of GB preparations with good solubility,stability,and the ability to cross the BBB remains a challenge.Herein,we propose a combinatorial strategy by conjugating GB with highly lipophilic docosahexaenoic acid(DHA)to obtain a covalent complex GB-DHA,which can not only enhance the pharmacological effect of GB,but can also be encapsulated in liposomes stably.The amount of finally constructed Lipo@GB-DHA targeting to ischemic hemisphere was validated 2.2 times that of free solution in middle cerebral artery occlusion(MCAO)rats.Compared to the marketed ginkgolide injection,Lipo@GB-DHA significantly reduced infarct volume with better neurobehavioral recovery in MCAO rats after being intravenously administered both at 2 h and 6 h post-reperfusion.Low levels of reactive oxygen species(ROS)and high neuron survival in vitro was maintained via Lipo@GB-DHA treatment,while microglia in the ischemic brain were polarized from the pro-inflammatory M1 phenotype to the tissue-repairing M2 phenotype,which modulate neuroinflammatory and angiogenesis.In addition,Lipo@GB-DHA inhibited neuronal apoptosis via regulating the apoptotic pathway and maintained homeostasis by activating the autophagy pathway.Thus,transforming GB into a lipophilic complex and loading it into liposomes provides a promising nanomedicine strategy with excellent CI/RI therapeutic efficacy and industrialization prospects.展开更多
基金supported by grants from the National Nature Science Foundation of China(81201444 and 81101401)
文摘BACKGROUND:Recent studies have showed that S100A8 has been implicated in the pathobiology of inflammatory disorders,and that cerebral ischemia reperfusion(l/R) rapidly activates inflammation responses via Toll-like receptor 4(TLR4).This study aimed to explore the expression of S100A8 and the relationship between S100A8 and TLR4 in focal cerebral ischemia reperfusion injury.METHODS:C3H/HeJ mice(n=30) and C3H/HeN mice(n=30) were divided randomly into a C3H/HeJ model group(n=18),a C3H/HeJ control group(n=12),a C3H/HeN model group(n=18),and a C3H/HeN control group(n=12).Middle cerebral artery l/R model in mice was produced using a thread embolism method.The brains of the mice were collected after ischemia for 1 hour and reperfusion for 12 hours.Stroke outcome was evaluated by determination of infarct volume and assessment of neurological impairment scores.Brain injury after cerebral l/R was observed by an optical microscope after TTC and HE dyeing.The immunofluorescence technique and real time PCR were used to test the expression level of S100A8 in brain damage.RESULTS:Compared with C3H/HeN mice,TLR4-deficient mice(C3H/HeJ) had lower infarct volumes and better outcomes in neurological tests.The levels of S100A8 increased sharply in the brains of mice after l/R injury.In addition,mice that lacked TLR4(C3H/HeJ) had lower expression of l/R-induced S100A8 than C3H/HeN mice in the model group,indicating that a close relationship might exist between the levels of S100A8 and TLR4.CONCLUSION:S100A8 interaction with TLR4 might be involved in brain damage and in inflammation triggered by l/R injury.
基金the Natural Science Foundation of Shandong Province, No. Y2004C04
文摘BACKGROUND: The application of exogenous antioxidant is always the focus in the prevention and treatment of cerebral ischemia. Phycocyanin has the effects against oxidation and inflammation, but its role in the pathophysiological process of cerebral ischemia reperfusion injury still needs further investigation. OBJECTIVE: To observe the effects of phycocyanin on the expression of superoxide dismutase (SOD), apoptosis and form of the nerve cells in rats after cerebral ischemia reperfusion injury. DESIGN: A randomized control animal experiment. SETTING: Institute of Cerebrovascular Disease, Medical School Hospital of Qingdao University. MATERIALS: Fifty-two healthy adult male Wistar rats of clean degree, weighing 220-260 g, were used. Phycocyanin was provided by the Institute of Oceanology, Chinese Academy of Sciences. METHODS: The experiments were carried out in Shangdong Key Laboratory for Prevention and Treatment of Brain Diseases from May to December 2005. ① All the rats were divided into three groups according to the method of random number table: sham-operated group (n=4), control group (n=24) and treatment group (n=24). Models of middle cerebral artery occlusion/reperfusion (MCAO/R) were established by the introduction of thread through external and internal carotid arteries in the control group and treatment group. After 1-hour ischemia and 2-hour reperfusion, rats in the treatment group were administrated with gastric perfusion of phycocyanin suspension (0.1 mg/g), and those in the control group were given saline of the same volume, and no treatment was given to the rats in the sham-operated group. ②The samples were removed and observed at ischemia for 1 hour and reperfusion for 6 and 12 hours and 1, 3, 7 and 14 days respectively in the control group and treatment group, 4 rats for each time point, and those were removed at 1 day postoperatively in the sham-operated group. Forms of the nerve cells were observed with toluidine blue staining. Apoptosis after cerebral ischemia reperfusion was detected with TUNEL technique. SOD expression was detected with immunohistochemical technique. ③ The intergroup difference was compared with the t test. MAIN OUTCOME MEASURES: The apoptosis of the nerve cells and SOD expression were mainly observed in each group. RESULTS: Finally, 52 rats were involved in the analysis of results. ① Number of apoptotic cells: In the sham-operated group, a few apoptotic cells could be observed in brain tissue. The apoptotic cells at each time point in the control group and treatment group were obviously more than those in the sham-operated group (P < 0.05). In the treatment group, the numbers of apoptotic cells at 12 hours, 1 and 3 days after reperfusion were significantly fewer than those in the control group, and those at 6 hours, 7 and 14 days were similar to those in the control group. ② Number of SOD positive cells: In the sham-operated group, there was weak expression of SOD in brain tissue, and the positive cells were extremely few, the positive cells at each time point were significantly more in the control group and treatment group than in the sham-operated group (P < 0.05). In the treatment group, the numbers of positive cells at 6 and 12 hours, 1 and 3 days after reperfusion were significantly fewer than those in the control group, and those at 7-14 days were similar to those in the control group. ③ Cellular forms: In the control group, the karyopyknosis occurred in the nerve cells, which were irregularly distributed, nucleolus disappeared, and some scattered cell fragments were observed. The forms of the nerve cells in the treatment group were generally normal. CONCLUSION: Phycocyanin plays a neuroprotective role in cerebral ischemia reperfusion injury by activating the SOD expression and inhibiting apoptosis.
基金supported by Natural Science Foundation of Shandong Province(No.:ZR2009CL018)
文摘Objective: To discuss the mechanism of low molecular weight GTP binding protein RAC1 in the injury of neural function based on building the rat model of cerebral ischemia reperfusion. Methods: Middle cerebral artery of rats was ligated and the ligature was released to restore the perfusion after 2 h, the rat model of cerebral ischemia reperfusion injury was built, while the middle cerebral artery was ligated. The rats were randomly divided into the sham group, cerebral ischemia reperfusion group(I/R group) and the group with the injection of RAC1 activity inhibitor NSC23766(NSC group). The survival and neurological severity score of rats in each group were observed and recorded. Nissl staining was employed to observe the nerve cells, and Western blot to detect expression of RAC1, superoxide dismutase and malondialdehyde. Results: Number of nerve cells for rats in NSC group was significantly more than that in I/R group, but significantly less than that in sham group, with the statistical difference(P<0.05). The brain water content for rats in NSC group was significantly lower than that in I/R group, but significantly higher than that in sham group, with the statistical difference(P<0.05). The expression of RAC1 and malondialdehyde for rats in NSC group was significantly lower than that in I/R group, but higher than that in sham group; while the expression of superoxide dismutase was lower than that in sham group, but higher than that in I/R group, with the statistical difference(P<0.05). Conclusions: The inhibition of RAC1 activity can reduce the oxidative stress, reduce the neurologic impairment because of cerebral ischemia reperfusion and thus protect the neural function.
基金supported by grants from Ministry of Human Resources and Social Security of the People’s Republic of China:Returned Overseas Personnel Science and Technology Activities Project Merit Funding(No.2015192)
文摘The aim of the present study was to investigate the effect of "nourishing liver and kidney" acupuncture therapy on motor and cognitive deficits,and the underlying mechanism following cerebral ischemia-reperfusion(I/R) via increasing the expression of brain derived neurotrophic factor(BDNF) and synaptophysin(SYN) in the hippocampus.Healthy adult male SD rats were randomly divided into sham operation group(n=51),model group(n=51),acupuncture group(n=51) and acupuncture control group(n=51).The middle cerebral I/R model was established.Acupunctures were performed in the acupuncture group and acupuncture control group at acupoints of Taixi(K103),Taichong(ST09) of both sides,for 30 min once daily every morning.The animals in the sham operation group and model group were conventionally fed in the cage,without any intervention therapy.The rats of each group were assessed with modified neurological severity scores(m NSS).The expression of BDNF and SYN in the hippocampus was detected by immunohistochemical SP method and the synaptic structure in hippocampus area was assessed morphologically and quantitatively at the 3rd,7th and 14 th day.The Morris water Maze(MWM) test was used to evaluate the rats' learning and memory abilities on the 15 th day after acupuncture.The animals in the acupuncture control group and sham operation group presented no neurological deficit.In the acupuncture group,the nerve functional recovery was significantly better than that in the model group at the 7th and 14 th day after modeling.The average MWM escape latency in the acupuncture group was shorter than that in the model group at the 3rd,4th and 5th day.The number of crossings of the platform quadrant in the acupuncture group was significantly more than that in the model group.At the each time point,the expression levels of BDNF and SYN in the hippocampal regions increased significantly in the model group as compared with the sham operation group and the acupuncture control group.In the acupuncture group,the expression levels of BDNF at the 7th and 14 th day increased more significantly than those in the model group.In the acupuncture group,the expression levels of SYN at the each time point increased more significantly than those in the model group.The post-synaptic density(PSD) was significantly increased and the synapse cleft width was narrowed in the acupuncture group as compared with other groups.The synaptic curvatures were improved obviously in the acupuncture group in contrast to the model group.It was concluded that the "nourishing liver and kidney" acupuncture therapy has positive effects on behavioral recovery,as well as learning and memory abilities,probably by promoting the expression of BDNF and SYN,and synaptic structure reconstruction in the ipsilateral hippocampus after I/R in rats.The "nourishing liver and kidney" acupuncture therapy can promote the functional recovery in rats after cerebral ischemia injury.
基金This study was supported by grants from the Innovation Foundation of Health and Family Planning Commission of Hubei Province （No. WJ2017M036） and the National Natural Science Foundation of China （No. 81471858）.
基金the National Natural Science Foundation of China(Nos.81560589,30960450,81173110 and 81560072)Yunnan Provincial Science and Technology Department(Nos.202105AF150015,202102AA310030,2018FE001(-026),2017FE467(-019),2014BC012,and 2017IC041)Yunnan Provincial Educational Department(Nos.2018JS161).
文摘Flavonoid glycoside scutellarin(SCU)has been widely applied in the treatment of cerebral ischemic diseases in China.In this article,we conducted research on the working mechanisms of SCU in hypoxia reoxygenation(HR)injury of isolated cerebral basilar artery(BA)and erebral ischemia reperfusion(CIR)injury in rat models.In isolated rat BA rings,HR causes endothelial dysfunction(ED)and acetylcholine(ACh)induces endothelium-dependent vasodilation.The myography result showed that SCU(100μM)was able to significantly improve the endothelium-dependent vasodilation induced by Ach.However,SCU did not affect the ACh-induced relaxation in normal BA.Further studies suggested that SCU(10-1000μM)dose-dependently induced relaxation in isolated BA rings which were significantly blocked by the cGMP dependent protein kinase(PKG)inhibitor Rp-8-Br-cGMPs(PKGI-rp,4μM).Pre-incubation with SCU(500μM)reversed the impairment of endothelium-dependent vasodilation induced by HR,but the reversing effect was blocked if PKGI-rp(4μM)was added.The brain slice staining test in rats’model of middle cerebral artery occlusion(MCAO)induced CIR proved that the administration of SCU(45,90 mg/kg,iv)significantly reduced the area of cerebral infarction.The Western blot assay result showed that SCU(45 mg/kg,iv)increased brain PKG activity and PKG protein level after CIR surgery.In conclusion,our findings suggested that SCU possesses the ability of protecting brain cells against CIR injury through vascular endothelium protection and PKG signal.
基金financially supported by Zhangjiakou Science and Technology Commission Foundation,No.1021095Dthe Hebei North University Foundation,No.Q2010018
文摘Rutaecarpine,an active component of the traditional Chinese medicine Tetradium ruticarpum,has been shown to improve myocardial ischemia reperfusion injury.Because both cardiovascular and cerebrovascular diseases are forms of ischemic vascular disease,they are closely related.We hypothesized that rutaecarpine also has neuroprotective effects on cerebral ischemia reperfusion injury.A cerebral ischemia reperfusion model was established after 84,252 and 504 μg/kg rutaecarpine were given to mice via intraperitoneal injection,daily for 7 days.Results of the step through test,2,3,5-triphenyl tetrazolium chloride dyeing and oxidative stress indicators showed that rutaecarpine could improve learning and memory ability,neurological symptoms and reduce infarction volume and cerebral water content in mice with cerebral ischemia reperfusion injury.Rutaecarpine could significantly decrease the malondialdehyde content and increase the activities of superoxide dismutase and glutathione peroxidase in mouse brain.Therefore,rutaecarpine could improve neurological function following injury induced by cerebral ischemia reperfusion,and the mechanism of this improvement may be associated with oxidative stress.These results verify that rutaecarpine has neuroprotective effects on cerebral ischemia reperfusion in mice.
基金the National Natural Science Foundation of China, No. 30972855/C160203
文摘The present study investigated the effects of the mitochondrial calcium uniporter inhibitor ruthenium red and the agonist spermine on cerebral edema in rats with cerebral ischemia reperfusion injury. Left middle cerebral artery occlusion (MCAO) was induced in rats using the suture method. Following 24 hours of ischemic reperfusion, neurological function scores of rats with MCAO, and rats pretreated with ruthenium red and spermine were significantly lower, however, water content of brain tissue, aquaporin 4 expression and immunoglobulin G (IgG) exudation were significantly higher than those of sham-operated rats. Compared with MCAO rats and spermine-treated rats, neurological function scores were considerably higher, and brain tissue water content, aquaporin 4 expression and IgG exudation decreased in ruthenium red-treated rats. These findings suggest that preventive application of the mitochondrial calcium uniporter inhibitor ruthenium red can significantly decrease aquaporin 4 and IgG expression, influence the permeability of the blood brain barrier, and thereby decrease the extent of cerebral edema.
基金supported by the Science and Technology Program of Suzhou Industrial Park in China
文摘Netrin-1 is currently one of the most highly studied axon guidance factors. Netrin-1 is widely expressed in the embryonic central nervous system, and together with the deleted in colorectal cancer and uncoordinated locomotion-5 homolog B receptors, netrin-1 plays a guiding role in the construction of neural conduction pathways and the directional migration of neuronal cells. In this study, we established a rat middle cerebral artery ischemia reperfusion model using the intraluminal thread technique. Immunofluorescence microscopy showed that the expression of netrin-1 and deleted in colorectal cancer in the ischemic penumbra was upregulated at 1 day after reperfusion, reached a peak at 14 days, and decreased at 21 days. There was no obvious change in the expression of uncoordinated locomotion-5 homolog B during this time period. Double immunofluorescence labeling revealed that netrin-1 was expressed in neuronal cells and around small vessels, but not in astrocytes and microglia, while deleted in colorectal cancer was localized in the cell membranes and protrusions of neurons and astrocytes. Our experimental findings indicate that netrin-1 may be involved in post-ischemic repair and neuronal protection via deleted in colorectal cancer receptors.
文摘AIBP has been gradually discovered and paid more and more attention.It is of great significance to explore the role of AIBP in cerebral ischemia-reperfusion injury and itse pathological mechanism.In this experiment,HT22 cells were divided into control group and experimental group.
文摘Objective: To study the effects of resveratrol (Res) on regulating apoptosis and autophagy in cerebral ischemia reperfusion (I/R) in rats. Methods: SD rats were selected as experimental animals and randomly divided into Sham group, I/R group and Res group. Sham group were given sham operation, I/R group were established into cerebral ischemia reperfusion models by suture method, and Res group were established into cerebral ischemia reperfusion models and then given resveratrol intervention. The protein levels of anti-apoptosis molecules, pro-apoptosis molecules and autophagy markers in brain tissues were measured 24 h after reperfusion. Results: Livin, Survivin, XIAP and p62 protein levels in brain tissue of I/R group were significantly lower than those of Sham group whereas CytC, AIF, Fas, FasL, Caspase-8, Caspase-9, LC3-Ⅱ, Beclin1, Bnip-3 and Atg5 protein levels were significantly higher than those of Sham group);Livin, Survivin, XIAP and p62 protein levels in brain tissue of Res group were significantly higher than those of I/R group whereas CytC, AIF, Fas, FasL, Caspase-8, Caspase-9, LC3-Ⅱ, Beclin1, Bnip-3 and Atg5 protein levels were significantly lower than those of I/R group. Conclusion: Resveratrol has a significant inhibitory effect on apoptosis and autophagy in cerebral ischemia reperfusion of rats.
文摘Objective:To study the protective effect of levothyroxine on myocardial and cerebral ischemia reperfusion injury during surgery under cardiopulmonary bypass.Methods: Patients who underwent valve replacement under cardiopulmonary bypass in Mianyang Central Hospital between March 2015 and December 2017 were selected and randomly divided into the Euthyrox group who received preoperative levothyroxine therapy and the control group who received routine preoperative intervention. The myocardial and cerebral injury indexes, pro-inflammatory and adhesion molecules as well as antioxidant indexes were measured before operation and 12 h after operation.Results: Twelve hours after operation, serum cTnI, LDH, CK-MB, H-FABP, NSE, S100B, CD11b/CD18, sP-selectin, IL-1 and IL-10 contents as well as SjvO2 levels of both groups were higher than those before operation whereas Cu-Zn SOD, CAT and GSH-Px contents were lower than those before operation, and serum cTnI, LDH, CK-MB, H-FABP, NSE, S100B, CD11b/CD18, sP-selectin, IL-1 and IL-10 contents as well as SjvO2 level of Euthyrox group were lower than those of control group whereas Cu-Zn SOD, CAT and GSH-Px contents were higher than those of control group.Conclusions:Levothyroxine has protective effect on the myocardial and cerebral ischemia reperfusion injury induced by inflammation and oxidative stress during surgery under cardiopulmonary bypass.
文摘Objective: To study the effects of sevoflurane pretreatment on cerebral ischemia reperfusion injury in mice. Methods: C56 BL/6J mice were selected as experimental animals and divided into control group, I/R group and Sev group. I/R group and Sev group were established into cerebral ischemia reperfusion injury models through suture method, and Sev group were given consecutive 4 days of sevoflurane pretreatment before model establishment. The ischemia reperfusion brain tissue was collected to determine the mRNA expression of apoptosis genes and the levels of oxidative stress indexes. Results: Bcl-2, HAX-1, Mcl-1 and Survivin mRNA expression as well as Prdx6 and SOD levels in brain tissue of I/R group were significantly lower than those of control group whereas NF-kB, p53, Noxa, PTEN and Fas mRNA expression as well as Nox4, ROS and MDA levels were significantly higher than those of control group;Bcl-2, HAX-1, Mcl-1 and Survivin mRNA expression as well as Prdx6 and SOD levels in brain tissue of Sev group were significantly higher than those of I/R group whereas NF-kB, p53, Noxa, PTEN and Fas mRNA expression as well as Nox4, ROS and MDA levels were significantly lower than those of I/R group. Conclusion: Sevoflurane pretreatment can inhibit the apoptosis and oxidative stress response to alleviate the cerebral ischemia reperfusion injury in mice.
文摘Objective:To study the effect of thyroid hormone (euthyrox) on myocardial and cerebral ischemia reperfusion injury in valve replacement under cardiopulmonary bypass.Methods:A total of 76 patients who received valve replacement under cardiopulmonary bypass in our hospital between January 2013 and December 2016 were collected and divided into control group (n=38) and observation group (n=38) according to random number table. Observation group took euthyrox orally 1 week before surgery, control group took vitamin C tablets orally at the same point in time, and both therapies lasted for 1 week. Before taking medicine and after cardiopulmonary bypass (before end of surgery), serum levels of myocardial enzyme spectrum indexes and nerve injury indexes were compared between the two groups of patients. Results: Before taking medicine, differences in the serum levels of myocardial enzyme spectrum indexes and nerve injury indexes were not statistically significant between the two groups of patients. After cardiopulmonary bypass, serum myocardial enzyme spectrum indexes cTnT, CK-MB,α-HBD and LDH levels in observation group were lower than those in control group;serum nerve injury indexes NSE, S100B and GFAP levels were lower than those in control group while bFGF level was higher than that in control group.Conclusion: Euthyrox intervention in valve replacement under cardiopulmonary bypass can effectively reduce the myocardial and cerebral ischemia reperfusion injury.
文摘Objective:To study the influence and molecular mechanism of ticagrelor on cerebral ischemia reperfusion injury in rats.Methods:SD rats were selected as experimental animals and divided into control group, model group, ticagrelor group and clopidogrel group, cerebral ischemic reperfusion injury models were made, then ticagrelor group were given intragastric administration of 150 mg ticagrelor, clopidogrel group were given intragastric administration of 90 mg clopidogrel. 1 week after intervention, the brain water content as well as the contents of oxidative stress molecules and inflammatory factors were measured.Results: Water content in brain, MDA, Ox-LDL, NF-kB, TNF-α, IL-1β and IL-6 contents in brain tissue as well as TNF-α, IL-1β and IL-6 contents in serum of model group were significantly higher than those of control group while SOD, GSH-Px and Prdx6 contents in brain tissue were significantly lower than those of control group;water content in brain, MDA, Ox-LDL, NF-kB, TNF-α, IL-1β and IL-6 contents in brain tissue as well as TNF-α, IL-1β and IL-6 contents in serum of ticagrelor group and clopidogrel group were significantly lower than those of model group while SOD, GSH-Px and Prdx6 contents in brain tissue were significantly higher than those of model group;water content in brain, MDA, Ox-LDL, NF-kB, TNF-α, IL-1β and IL-6 contents in brain tissue as well as TNF-α, IL-1β and IL-6 contents in serum of ticagrelor group were significantly lower than those of clopidogrel group while SOD, GSH-Px and Prdx6 contents in brain tissue were significantly higher than those of clopidogrel group. Conclusion:Ticagrelor can be more effective in inhibiting oxidative stress response and inflammatory response, and reducing the cerebral ischemia reperfusion injury than clopidogrel.
基金supported by the National Natural Science Foundation of China,Nos.82104158(to XT),31800887(to LY),31972902(to LY),82001422(to YL)China Postdoctoral Science Foundation,No.2020M683750(to LY)partially by Young Talent Fund of University Association for Science and Technology in Shaanxi Province of China,No.20200307(to LY).
文摘β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic stroke.Here we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced apoptosis.Further investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic stroke.In addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its activity.In conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways.
基金supported by the Natural Science Foundation of Anhui Province of China,No.2208085Y32Scientific Research Plan Project of Anhui Province of China,No.2022AH020076the Chen Xiao-Ping Foundation for the Development of Science and Technology of Hubei Province,No.CXPJJH12000005-07-115(all to CT).
文摘Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury.Various calcium channels are involved in cerebral ischemia/reperfusion injury.Cav3.2 channel is a main subtype of T-type calcium channels.T-type calcium channel blockers,such as pimozide and mibefradil,have been shown to prevent cerebral ischemia/reperfusion injury-induced brain injury.However,the role of Cav3.2 channels in cerebral ischemia/reperfusion injury remains unclear.Here,in vitro and in vivo models of cerebral ischemia/reperfusion injury were established using middle cerebral artery occlusion in mice and high glucose hypoxia/reoxygenation exposure in primary hippocampal neurons.The results showed that Cav3.2 expression was significantly upregulated in injured hippocampal tissue and primary hippocampal neurons.We further established a Cav3.2 gene-knockout mouse model of cerebral ischemia/reperfusion injury.Cav3.2 knockout markedly reduced infarct volume and brain water content,and alleviated neurological dysfunction after cerebral ischemia/reperfusion injury.Additionally,Cav3.2 knockout attenuated cerebral ischemia/reperfusion injury-induced oxidative stress,inflammatory response,and neuronal apoptosis.In the hippocampus of Cav3.2-knockout mice,calcineurin overexpression offset the beneficial effect of Cav3.2 knockout after cerebral ischemia/reperfusion injury.These findings suggest that the neuroprotective function of Cav3.2 knockout is mediated by calcineurin/nuclear factor of activated T cells 3 signaling.Findings from this study suggest that Cav3.2 could be a promising target for treatment of cerebral ischemia/reperfusion injury.
基金supported by the National Natural Science Foundation of China,Nos.82102295(to WG),82071339(to LG),82001119(to JH),and 81901994(to BZ).
文摘Studies have shown that C1q/tumor necrosis factor-related protein-6 (CTRP6) can alleviate renal ischemia/reperfusion injury in mice. However, its role in the brain remains poorly understood. To investigate the role of CTRP6 in cerebral ischemia/reperfusion injury associated with diabetes mellitus, a diabetes mellitus mouse model of cerebral ischemia/reperfusion injury was established by occlusion of the middle cerebral artery. To overexpress CTRP6 in the brain, an adeno-associated virus carrying CTRP6 was injected into the lateral ventricle. The result was that oxygen injury and inflammation in brain tissue were clearly attenuated, and the number of neurons was greatly reduced. In vitro experiments showed that CTRP6 knockout exacerbated oxidative damage, inflammatory reaction, and apoptosis in cerebral cortical neurons in high glucose hypoxia-simulated diabetic cerebral ischemia/reperfusion injury. CTRP6 overexpression enhanced the sirtuin-1 signaling pathway in diabetic brains after ischemia/reperfusion injury. To investigate the mechanism underlying these effects, we examined mice with depletion of brain tissue-specific sirtuin-1. CTRP6-like protection was achieved by activating the sirtuin-1 signaling pathway. Taken together, these results indicate that CTRP6 likely attenuates cerebral ischemia/reperfusion injury through activation of the sirtuin-1 signaling pathway.
基金National Key Research and Development Program of China,Grant/Award Number:2021YFF0702402National Natural Science Foundation of China,Grant/Award Number:32070531。
文摘Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symptoms are caused by numerous complex variant types of the circle.Additionally,the lack of an evaluation system for the cer-ebral ischemia/reperfusion(I/R)model of gerbils has shackled the application of this model.Methods:We created a symptom-oriented principle and detailed neurobehavioral scoring criteria.At different time points of reperfusion,we analyzed the alteration in locomotion by rotarod test and grip force score,infarct volume by triphenyltetrazo-lium chloride(TTC)staining,neuron loss using Nissl staining,and histological charac-teristics using hematoxylin-eosin(H&E)straining.Results:With a successful model rate of 56%,32 of the 57 gerbils operated by our method harbored typical features of cerebral I/R injury,and the mortality rate in the male gerbils was significantly higher than that in the female gerbils.The suc-cessfully prepared I/R gerbils demonstrated a significant reduction in motility and grip strength at 1 day after reperfusion;formed obvious infarction;exhibited typi-cal pathological features,such as tissue edema,neuronal atrophy and death,and vacuolated structures;and were partially recovered with the extension of reperfu-sion time.Conclusion:This study developed a new method for the unilateral common carotid artery ligation I/R model of gerbil and established a standardized evaluation system for this model,which could provide a new cerebral I/R model of gerbils with more practical applications.
基金This research was funded by the National Natural Science Foundation of China(No.81773911,81690263 and 81573616)the Development Project of Shanghai Peak Disciplines-Integrated Medicine(No.20180101).
文摘Cerebral ischemia-reperfusion injury(CI/RI)remains the main cause of disability and death in stroke patients due to lack of effective therapeutic strategies.One of the main issues related to CI/RI treatment is the presence of the blood-brain barrier(BBB),which affects the intracerebral delivery of drugs.Ginkgolide B(GB),a major bioactive component in commercially available products of Ginkgo biloba,has been shown significance in CI/RI treatment by regulating inflammatory pathways,oxidative damage,and metabolic disturbance,and seems to be a candidate for stroke recovery.However,limited by its poor hydrophilicity and lipophilicity,the development of GB preparations with good solubility,stability,and the ability to cross the BBB remains a challenge.Herein,we propose a combinatorial strategy by conjugating GB with highly lipophilic docosahexaenoic acid(DHA)to obtain a covalent complex GB-DHA,which can not only enhance the pharmacological effect of GB,but can also be encapsulated in liposomes stably.The amount of finally constructed Lipo@GB-DHA targeting to ischemic hemisphere was validated 2.2 times that of free solution in middle cerebral artery occlusion(MCAO)rats.Compared to the marketed ginkgolide injection,Lipo@GB-DHA significantly reduced infarct volume with better neurobehavioral recovery in MCAO rats after being intravenously administered both at 2 h and 6 h post-reperfusion.Low levels of reactive oxygen species(ROS)and high neuron survival in vitro was maintained via Lipo@GB-DHA treatment,while microglia in the ischemic brain were polarized from the pro-inflammatory M1 phenotype to the tissue-repairing M2 phenotype,which modulate neuroinflammatory and angiogenesis.In addition,Lipo@GB-DHA inhibited neuronal apoptosis via regulating the apoptotic pathway and maintained homeostasis by activating the autophagy pathway.Thus,transforming GB into a lipophilic complex and loading it into liposomes provides a promising nanomedicine strategy with excellent CI/RI therapeutic efficacy and industrialization prospects.
