摘要
Cerebral ischemia/reperfusion injury （CIRI） is a complex cascade reaction process in which the blood flow and oxygen supply of brain tissue in the infarcted area recover after cerebral ischemia， resulting in secondary injury of ischemic brain tissue. At present， thrombolysis as soon as possible and restoration of cerebral blood supply are still the only strategies for the treatment of stroke， but a considerable number of patients' symptoms will be more serious after reperfusion， making patients face adverse outcomes such as neurological function injury and even death and seriously affecting the quality of life and safety of patients. Therefore， an in-depth exploration of the mechanism and treatment strategy of CIRI has important clinical significance. The phosphatidylinositol 3- kinase （PI3K）/protein kinase B （Akt） signaling pathway is one of the classic anti-apoptosis/reproductive-promoting signal transduction pathways， which is responsible for cell proliferation， growth， and differentiation. It is the key cascade signaling pathway of CIRI， located at the core site in many mechanisms such as mitochondrial disorder， apoptosis， autophagy， oxidative stress， and inflammation. It is closely related to the occurrence and development of CIRI. Traditional Chinese medicine has been used in the clinical treatment of stroke and its complications for thousands of years， and the clinical effect of traditional Chinese medicine in the prevention and treatment of CIRI has been affirmed by a large number of research results in recent years. It is further clarified that the monomers， active components， and their compound prescriptions of traditional Chinese medicine can directly or indirectly regulate the PI3K/Akt signaling pathway by virtue of the biological advantages of multi-targets， multi-components， and multi-pathways and play an overall protective role in CIRI. By analyzing the related research progress of traditional Chinese medicine in China and abroad in recent years， the authors summarized the role and mechanism of regulating the PI3K/Akt signaling pathway in the prevention and treatment of CIRI， so as to provide further theoretical basis for the study of the mechanism of clinical prevention and treatment of CIRI.
摘要
Ischemia and hypoxia cause functional damage to brain tissues during stroke， and when blood supply is restored to brain tissues after ischemia， a large number of free radicals and calcium overload cause cerebral ischemia-reperfusion injury， which further aggravates the condition. Autophagy is a self-protection mechanism that maintains the homeostasis of the intracellular environment， but excessive autophagy causes brain tissue damage. MiRNA is a small endogenous non-coding RNA molecule that regulate various physiological activities at the gene level by binding to complementary sequences in the 3 '- UTR of its target gene mRNA， leading to translation inhibition or mRNA degradation. MiRNA not only directly acts on autophagy related proteins， but also participates in autophagy regulation induced by ischemia/reperfusion through various signaling pathways. However， there is still a lack of systematic induction and analysis of miRNA regulation of autophagy signaling pathways induced by cerebral ischemia/reperfusion. This article reviews the regulation of cellular autophagy during cerebral ischemia/ reperfusion by miRNA-124， miRNA-298， miRNA-202-5p， miRNA-142， miRNA-26b and so on through different signaling pathways， providing a systematic and theoretical approach for the study of autophagy in stroke.
摘要
Objective To study the effect and mechanism of Anchusa italica Retz on cerebral ischemia-reperfusion inju-ry in rats based on the target network of active compounds in Anchusa italica Retz.Methods The rat model of cerebral ische-mia-reperfusion injury was established by the thread occlusion method.After performing ischemia for 1.5 h and then reperfusion for 24 h,the neurological function of rats was scored and the volume of cerebral infarction was measured by the 2,3,5-triphenyltet-razolium chloride staining method.The molecular network analysis technique of network pharmacology,protein-protein interaction network,gene ontology(GO)enrichment analysis,KEGG signal pathway analysis,and molecular docking was used to study the mechanism of Anchusa italica Retz in the treatment of cerebral ischemia-reperfusion injury.Results The administration of An-chusa italica Retz could significantly improve the neurobehavioral dysfunction caused by cerebral ischemia-reperfusion injury and reduce the pathological injury of brain tissue.Anchusa italica Retz could regulate inflammation,apoptosis,protein phosphorylation,and other biological processes through 143 ischemic stroke-related targets,and interfere with the TNF signal pathway,VEGF signal pathway,HIF-1 signal pathway,and other pathways.Conclusion Network pharmacology and experimental verification had shown that Anchusa italica Retz could effectively reduce brain injury and protect neurological function through multi-target,multi-mechanism,and holistic treatment of cerebral ischemia-reperfusion injury.
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Objective:To investigate the role of HMGB1-TLR4-NF-κB signaling pathway in cerebral ischemia-reperfusion in-jury and the effect of adenosine preconditioning on the signaling pathway.Methods:Total 80 adult male Sprague-Dawley rats weighing 220～270 g were selected from the Animal Center of Xinxiang Medical University.The rats were randomly divided into F group(sham operation group),I/R group(ischemia reperfusion group)and AP group(adenosine preconditioning group).The MCAO model of rats was established by wire embolization.Quantitative analysis of neural function in successfully modeled rats using animal behavior scor-ing method,the morphological changes of brain cells were observed by HE staining,TTC staining was used to observe cerebral infarc-tion and cerebral infarction volume was calculated;Immunohistochemical staining was used to detect HMGB1,TLR4 and NF-κB pro-tein expression levels in brain tissues of each group.The data were statistically analyzed by one-way ANOVA in SPSS26.0 software.Results:After ischemia reperfusion,the neurological function of I/R group and AP group showed different degrees of impairment,and the neurological function scores of the two groups were significantly higher than that of F group,the difference was statistically signifi-cant(P<0.05),and the neurological function of the AP group was significantly less than that of I/R group,the difference was also sta-tistically significant(P<0.05).TTC staining showed that AP group,I/R group rat cerebral infarction volume was significantly more than F group[(93.670±4.509)mm3,(123.670±7.234)mm3 vs(0.000±0.000)mm3],and AP group rats infarction volume was signifi-cantly reduced than that in I/R group,the difference had statistical significance(P<0.05).Immunohistochemistry showed that HMGB1,TLR4,NF-κB protein in F group with a small amount of expressions in rats,while significantly expressed in AP group and I/R group relatively,and the AP group of each subgroup rat HMGB1,TLR4,NF-κB protein expressions significantly lower than the amount of I/R group,the difference had statistical significance(P<0.05).Conclusion:Adenosine preconditioning can reduce the expressions of HMGB1,TLR4 and NF-κB protein,and then protect the rats with cerebral ischemia-reperfusion injury.
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Objective To investigate the mechanism of icariin regulating the NLRP3 inflammasome in the treatment of cerebral ischemia-reperfusion injury in rats.Methods A rat model of focal cerebral ischemia-reperfusion was induced using the thread embolism method.At 24 hours post-operation,the rats were randomly allocated into a sham operation group,model group,butylphthalide group(70 mg/kg),ICA-low dose(20 mg/kg),ICA-middle dose(40 mg/kg),and ICA-high dose(80 mg/kg)groups.The corresponding drugs were administered by gavage at 10 mL/kg once a day for 13 consecutive days.One hour after the last administration,neurological function was scored.The cerebral cortex was observed by hematoxylin-eosin(HE)staining.Expression of interleukin(IL)-1β and IL-18 in the cerebral cortex was determined by immunohistochemistry.Expression of NLRP3,ASC,and Caspase-1 in the cerebral cortex was determined by Western Blot.Results In contrast to the sham operation group,there was a notable increase in neural function scores within the model group.The ischemic area around the visible cerebral cortex showed neuron necrosis at various level or glial cell proliferation,and the number of intact neurons was significantly reduced.IL-1β and IL-18 positive cells were significantly increased.Expression of NLRP3,ASC,and Caspase-1 was significantly increased(P＜0.01,P＜0.05).After treatment with icariin,the neural function score was decreased significantly.The degree of neuronal necrosis in the peri-ischemic area was significantly reduced,and the number of intact neurons was significantly increased.IL-1 β and IL-18-positive cells were decreased significantly.Expressions of NLRP3,ASC,and Caspase-1 were significantly decreased(P＜0.01,P＜0.05).Conclusions Treatment of cerebral ischemia-reperfusion injury by icariin may be related to regulation of the NLRP3 inflammasome.
摘要
AIM To explore the effects of Buyang Huanwu Decoction on mitochondrial oxidative damage and PKCε-Nampt pathway in rats following cerebral ischemia reperfusion(I/R).METHODS The rats were randomly divided into the sham operation group,the model group,Buyang Huanwu Decoction group(14.3 g/kg)and edaravone group(3 mg/kg).Except those of the sham operation group,SD rats of other groups were induced into models of brain I/R injury by MCAO method,followed by corresponding drug administration 24 hours after operation.After 7 days of administration,the rats had their neurological deficit evaluated by neurological function scoring;thier expression of neuron marker MAP-2 detected by immunofluorescence staining;their neuron damage observed and the oxidative damage evaluated through assessment of their ROS levels and MDA and SOD activities;their changes of mitochondrial membrane potential detected by fluorescent probe JC-1;their ratio of NAD+/NADH detected using modified enzyme circulation method;their expressions of PKCε,p-PKCε and Nampt proteins detected with Western blot;and their positive expressions of p-PKCε and Nampt proteins detected with immunohistochemistry method.RESULTS Compared with the model group,Buyang Huanwu Decoction group shared decreased cerebral infarction volume and neurological function score(P<0.05);increased cerebral fluorescence intensity of MAP-2(P<0.05);reduced neuronal damage,decreased cerebral levels of ROS and MDA(P<0.05);increased SOD activity,mitochondrial membrane potential and NAD+/NADH ratio(P<0.05);and increased protein expressions of p-PKCε and Nampt(P<0.05).CONCLUSION Buyang Huanwu Decoction can improve mitochondrial function and reduce brain I/R injury in rats by activating their PKCε-Nampt signaling pathway.
摘要
AIM To investigate the effects of Zhuangyao Shuanglu Tongnao Formula on neuronal apoptosis in rats with cerebral ischemia-reperfusion injury based on the study of oxidative stress and inflammatory response.METHODS The rats were randomly divided into the sham operation group,the model group,the edaravone group(3.0 mg/kg),the low,medium and high dose groups(9.0,18.0,36.0 g/kg)of Zhuangyao Shuanglu Tongnao Formula,with 18 rats in each group.The middle cerebral artery occlusion/reperfusion was conducted by thread embolism method to simulate cerebral ischemia reperfusion injury in rats followed by 6 days corresponding drugs administration.Subsequently,the rats had their neurological function deficit scored by Zeal Longa scoring method;their sizes of cerebral infarction areas measured by TTC staining;their pathological damage and apoptosis of neurons in hippocampal CA1 area of ischemic penumbra of the brain tissue detected by HE staining and TUNEL staining;their SOD activity and levels of GSH,MDA,IL-6,IL-1β,TNF-α in brain tissue detected by kits;and their protein expressions of Bax,Bcl-2,caspase-3,cleaved-capase-3,TLR4,NF-κB p65,Nrf2,HO-1 in rat brain tissue determined by Western blot.RESULTS Compared with the model group,the groups intervened with edaravone,medium and high dose of Zhuangyao Shuanglu Tongnao Formula displayed improvements in the scores of nerve function defects,the rate of cerebral infarction,the rate of neuronal apoptosis,the levels of IL-6,IL-1β,TNF-α and MDA in the ischemic penumbra of brain tissues,the protein expressions of Bax and TLR4,the ratio of cleaved-capase-3/caspase-3 and p-NF-κB p65/NF-κB p65(P＜0.05),the levels of GSH,the activity of SOD and the protein expressions of Bcl-2,Nrf2 and HO-1(P＜0.05).CONCLUSION Being an inhibitor of oxidative stress and inflammatory response,Zhuangyao Shuanglu Tongnao Formula can alleviate brain injury in rats with cerebral ischemia reperfusion injury through the inhibition of neuronal apoptosis and improvement of neural function mediated by the inhibition of TLR4/NF-κB signal pathway and activation of Nrf2/HO-1 signal pathway.
摘要
Objective:To explore the role and mechanism of neurotrophin-3(NT-3)in promoting neurological func-tion recovery after cerebral ischemia-reperfusion injury in rats.Methods:Twenty-four SD rats were randomly divided into sham operation group(Sham),middle cerebral artery occlusion/reperfusion(MCAO/R)group,and MCAO/R+NT-3 group.The neurological function scores of rats in each group were evaluated using the modified Garcia score.Western Blot was used to detect the expression of NT-3 and LC3B in brain tissues of rats.Culture dishes with the same density of neurons were randomly divided into normal group(Normal),oxygen-glucose deprivation(OGD)group,OGD+NT-3 group,OGD+NT-3+PF-06273340(TrkC inhibitor)group,OGD+NT-3+ZSTK474(PI3K inhibitor)group,and OGD+NT-3+CCT128930(AKT inhibitor)group.Western Blot was used to detect the expression of TrkC,the phosphorylation of PI3K/AKT,and LC3B in neurons.The morphological changes of neurons and the phenomenon of neuronal autophagy were observed using autophagy-specific fluorescent staining.Results:The animal experiment found that the expression of NT-3 increased in the brain tissue with ischemia-reperfusion injury(P＜0.05),and after the treatment with exogenous NT-3,the modified Garcia score increased(P＜0.05),and the level of autophagy weakened(P＜0.05).The cell experiment found that NT-3 can inhibit neuronal autophagy under ischemic hypoxia and maintain the neuronal morphology to the maximum extent.After using PF-06273340,the expression of p-PI3K and p-AKT de-creased(P＜0.05).After using ZSTK474 and CCT128930,the autophagy-inhibiting effect of NT-3 weakened(P＜0.05).Conclusion:NT-3 inhibits autophagy via the PI3K/AKT signaling pathway to maintain neuronal survival,thereby promoting the recovery of neurological function after cerebral ischemia-reperfusion injury in rats.
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Objective To investigate the potential effect and mechanism of curcumin in inhibiting synaptic injury in the cortex of rats with cerebral ischemia-reperfusion. Methods Sprague-Dawley rats were divided into sham-operated group, model group, low-dose curcumin (50 mg/kg) group, and high-dose curcumin (100 mg/kg) group. A model of middle cerebral artery occlusion for 2 hours and reperfusion for 24 hours was constructed, and curcumin was administered. Based on the neurological function score, the effects of curcumin on cerebral infarct volume, synaptic ultrastructure changes, inflammatory cell infiltration, and the expression of NLRP3, Caspase-1, Synapsin1, and CAMKⅡ were observed after the end of the animal treatment. Results The neurological function scores were 0, 3.25±0.43, 2.50±0.50, and 1.50±0.50 for the sham-operated group, model group, low-dose curcumin group, and high-dose curcumin group, respectively. The percentage of cerebral infarct volume was 0, (38.89±2.21)%, (33.48±1.77)%, and (23.69±2.19)%, respectively. Compared with the sham operation group, the model group had severe synaptic ultrastructure damage, extensive inflammatory cell infiltration, significantly increased expression of Caspase-1 and NLRP3 (P < 0.5), and significantly decreased expression of Synapsin1 and CAMKⅡ (P < 0.5). Curcumin treatment significantly inhibited synaptic damage, reduced inflammatory cell infiltration, decreased the expression of Caspase-1 and NLRP3 (P < 0.5), and increased the expression of Synapsin1 and CAMKII (P < 0.5), when compared with the model group. Conclusion Ischemia-reperfusion-mediated synaptic injury in rat brain triggers an inflammatory response in cortical nerve cells, and curcumin alleviates synaptic damage and reduces brain injury by inhibiting inflammatory factor levels.
摘要
OBJECTIVE To explore the protective effect and mechanism of Longshengzhi capsules on cerebral ischemia- reperfusion injury in rats. METHODS The model of middle cerebral artery occlusion （MCAO） was established by using the improved thread occlusion method. The experiment was divided into six groups： sham surgery group （only separating blood vessels without inserting thread plugs， given the same volume of normal saline）， model group （modeling， given the same volume of normal saline）， nimodipine group （positive control， modeling， dose of 20 mg/kg）， and low-dose， medium-dose， and high-dose groups of Longshengzhi capsules （modeling， doses of 0.72， 1.44 and 2.88 g/kg， respectively）， with 10 mice in each group. Each group was given corresponding medication solution/normal saline by gavage， once a day， for 7 consecutive days. One hour after the last administration， the Zea Longa scoring method was used to score the neurological deficits in each group of rats， and the ABC enzyme-linked immunosorbent assay was used to detect the serum levels of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） in rats； TTC staining was used to observe the volume of cerebral infarction in rats and calculate the cerebral infarction volume ratio. Hematoxylin eosin staining was used to observe the pathological changes in the brain tissue of rats. Immunohistochemical staining was used to detect the positive expression of NLRP3 protein in the brain tissue of rats. Real-time fluorescence quantitative PCR was used to detect mRNA relative expressions of Toll-like receptor 4 （TLR4） and nuclear factor-κB （NF-κB） in the brain tissue of rats. Western blot assay was adopted to detect the relative expressions of TLR4， NLRP3 and phosphorylated NF-κB （p-NF-κB） protein in the brain tissue of rats and its intracellular NF-κB protein. RESULTS Compared with the sham surgery group， the neural dysfunction score， serum levels of TNF-α and IL-6， cerebral infarction volume ratio， relative expression levels of NF-κB and TLR4 mRNA， as well as protein relative expressions of TLR4， NLRP3 and p-NF-κB in the brain tissue， and relative protein expression of intracellular NF-κB were increased significantly in the model group （P＜0.01）； the enlarged gap and significant edema were observed in cortical nerve cells of brain tissue in rats， with a large amount of inflammatory cell infiltration； the positive expression of NLRP3 protein in brain tissue of rats obviously increased. Compared with the model group， the levels of the above indicators in the medium-dose and high-dose groups of Longshengzhi capsules， as well as the Nimodipine group， were reversed to varying degrees， and most differences were statistically significant （P＜0.05 or P＜0.01）； the pathological morphology observation showed a significant improvement， and the positive expression of NLRP3 protein in the brain tissue of rats was obviously reduced. CONCLUSIONS Longshengzhi capsules may inhibit TLR4/NF-κB/NLRP3 signaling pathway and neuroinflammatory response， thereby achieving a protective effect against cerebral ischemia-reperfusion injury in rats.
摘要
Aim To investigate the regulatory effect of geraniol on Nrf2/HO-1 signaling pathway after cerebral ischemia-reperfusion(I/R)in rats. Methods In this experiment,all the male SD rats were randomly divided into nine groups receiving the following treatments:sham operation(sham); sham operation+200 mg·kg-1 geraniol; I/R; I/R+50 mg·kg-1 geraniol; I/R+100 mg/kg geraniol; I/R+200 mg·kg-1 geraniol; edaravone; I/R+ brusatol(Nrf2 inhibitor); I/R+200mg·kg-1 geraniol+brusatol. All rats received intraperitoneal injection of geraniol for five consecutive days before MCAO and again after MCAO. During the construction of cerebral I/R injury models,the blood vessels were isolated without any suture in the sham operation and the sham operation +200 mg·kg-1 geraniol groups while the blood vessels with suture in other groups. The damage of neurological function was evaluated by the modified rating scale for neurological function. The TTC,HE and Tunel staining methods were used to determine the cerebral infarction volume,the damage of the ischemic cortex and the apoptosis of cortical cells,respectively. The oxidative stress-related parameters then were measured. The protein expressions of Nrf2 and HO-1 were detected by immunohistochemical staining and the target protein expressions of the injured cortex were detected by Western blot. Results Compared with the model group,it was found that the geraniol treatment significantly repaired neural injury,reduced cerebral infarction volume,cerebral cortex damage and cell apoptosis. Meanwhile,geraniol intervention could significantly increase the expression of Nrf2/HO-1 protein in the right-sided cortex and reduce oxidative stress level. Conclusion Geraniol can attenuate cerebral injury induced by ischemia-reperfusion in rats via activating Nrf2/HO-1 signaling pathway.
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BACKGROUND:Croton cream can activate ERK pathways and have anti-apoptotic effects on neuronal cells.It is not clear whether it synergistically exerts anti-apoptotic effects by inhibiting the activation of JNK and p38 pathways. OBJECTIVE:To explore the effects and mechanisms of croton cream on neuronal damage and apoptosis in the ischemic cortex of rats with cerebral ischemia-reperfusion injury. METHODS:(1)Ninety Sprague-Dawley rats were randomly divided into sham operation group,model group,croton cream low-dose group,croton cream medium-dose group,croton cream high-dose group and nimodipine group,with 15 rats in each group.Except for the sham operation group,animal models of middle cerebral artery occlusion were prepared in rats by the thread method.Rats in the three croton cream groups were given 20,40,and 60 mg/kg croton cream,respectively.Rats in the sham operation and model groups were given the same amount of normal saline,once a day,for 7 consecutive days.The optimal concentration of croton cream,namely the high dose of croton cream,was selected based on neurological deficit score,TTC staining,brain tissue water content,hematoxylin-eosin staining and Nissl staining.(2)Another 120 Sprague-Dawley rats were randomly divided into sham operation group,model group,croton cream group,JNK inhibitor group,croton cream+JNK inhibitor group,p38 MAPK inhibitor group,croton cream+p38 MAPK inhibitor group,and nimodipine group,with 15 rats in each group.Animal models of middle cerebral artery occlusion were prepared using the thread method in all the groups except in the sham operation group.Thirty minutes before modeling,10 μL of SP600125(JNK inhibitor)and 10 μL of SB203580(p38 MAPK inhibitor)were injected into the lateral ventricle of the rats,respectively.Rats in croton cream groups were intragastrically given 60 mg/kg croton cream.Seven days later,the JNK/p38 MAPK signaling pathway,apoptosis-related proteins and cell apoptosis were detected by western blot,TUNEL staining and flow cytometry,respectively. RESULTS AND CONCLUSION:(1)Compared with the sham operation group,neurological deficit score,cerebral water content,cerebral infarction volume and apoptosis rate were significantly increased in the model group(P<0.05),where nerve cells showed scattered distribution.Compared with the model group,neurological deficit score,water content of brain tissue and cerebral infarction volume were significantly decreased in the croton cream medium-dose group,high-dose group and nimodipine group(P<0.05),and the pathological morphology of nerve cells was significantly improved.(2)Compared with the JNK inhibitor group,p-JNK/JNK,p-p38/p38 and Bax expressions in rat brain tissue and the apoptotic rate were significantly decreased in the croton cream+inhibitor groups(P<0.05),while the expression of and Bcl-2 was significantly increased(P<0.05).To conclude,croton cream may inhibit the activation of JNK/p38 MAPK signaling pathway and reduce neuronal apoptosis to achieve neuroprotective effects in rats with cerebral ischemia-reperfusion injury.
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BACKGROUND:Inflammation is one of the important factors that induce cerebral ischemia-reperfusion injury.Studies have shown that electroacupuncture can effectively reduce inflammation after ischemic stroke and improve the symptoms of neurological deficits,but the mechanism is not clear. OBJECTIVE:To observe the effect of electroacupuncture on Toll-like receptor 4/nuclear factor-κB in rats with cerebral ischemia-reperfusion injury. METHODS:Forty-eight male Sprague-Dawley rats were randomly divided into sham operation group,model group and electroacupuncture group,with 16 rats in each group.The rat model of cerebral ischemia-reperfusion injury was prepared by middle cerebral artery occlusion.At 24 hours after modeling,the rats in the electroacupuncture group were treated with electroacupuncture,once a day,20 minutes each time,for a total of 5 days.The sham operation group and the model group did not do any intervention.After 5 days of intervention,Longa method was used to evaluate the degree of neurological injury in rats.Triphenyl tetrazolium chloride staining and hematoxylin-eosin staining were used to measure the volume of cerebral infarction and the pathological changes of brain tissue in rats.Serum interleukin-6,interleukin-18 and tumor necrosis factor-α were detected by ELISA.Expressions of Toll-like receptor 4 and nuclear factor-κB in the cerebral cortex at mRNA and protein levels were detected by fluorescence quantitative PCR and western blot,respectively. RESULTS AND CONCLUSION:Compared with the sham operation group,the neurological function scores,serum interleukin-6,interleukin-18,and tumor necrosis factor-α levels,Toll-like receptor 4 and nuclear factor-κB mRNA and protein expression levels were significantly higher in the model group(P＜0.01).Compared with the model group,electroacupuncture significantly reduced the neurological function scores,serum interleukin-6,interleukin-18,and tumor necrosis factor-α levels,Toll-like receptor 4 and nuclear factor-κB mRNA and protein expression levels(P＜0.05,P＜0.01).Compared with the sham operation group,the volume of cerebral infarction in the model group increased significantly(P＜0.01).Compared with the model group,the volume of cerebral infarction in the electroacupuncture group decreased(P＜0.05).In the model group,the arrangement of neurons was disordered,some nerve cells disappeared,nuclei presented with pyknosis and incomplete structure.After electroacupuncture intervention,the degree of neuronal degeneration and neuronal loss in the cerebral cortex of rats were reduced compared with those in the model group.To conclude,electroacupuncture can significantly improve the neurobehavior of rats with cerebral ischemia-reperfusion injury,reduce brain tissue injury,and effectively reduce the level of serum inflammatory factors.The mechanism may be related to the inhibition of Toll-like receptor 4/nuclear factor-κB signaling pathway.
摘要
BACKGROUND:Oxidative injury is considered to be one of the important factors of cerebral ischemia-reperfusion injury.Superoxide dismutase 2(SOD2)is a key mitochondrial antioxidant molecule,and fenofibrate can regulate the expression of SOD2 by activating peroxisome proliferator-activated receptor α. OBJECTIVE:To explore whether the mechanism of fenofibrate in the treatment of cerebral ischemia-reperfusion injury depends on the expression of SOD2. METHODS:The TALENs system was used to construct SOD2 transgenic mice.The transgenic mice were genotyped by PCR and DNA sequencing techniques.The expression of SOD2 protein in transgenic mice was detected by western blot assay.Wild-type and SOD2 transgenic mice were randomly divided into four groups:wild-type control group(n=6),wild-type fenofibrate group(n=6),SOD2 transgenic control group(n=5)and SOD2 transgenic fenofibrate group(n=5).A mouse model of middle cerebral artery occlusion was prepared using the suture-occlusion method.After 90 minutes of ischemia,the thread was removed to reperfuse cerebral blood flow for 30 minutes.A cerebral blood flow monitor was used to monitor local cerebral blood flow.Brain tissue slices were taken for 2,3,5-triphenyltetrazolium chloride staining to analyze the situation of cerebral infarction in each group. RESULTS AND CONCLUSION:After PCR and DNA sequencing analysis,nine SOD2+/+ transgenic mice were successfully constructed.After cerebral ischemia-reperfusion,the wild-type fenofibrate group showed partial recovery of cerebral blood flow and significantly reduced cerebral infarction volume compared with the wild-type control group(P<0.001).There was no significant difference in cerebral blood flow and cerebral infarction volume between the SOD2 transgenic fenofibrate group and the SOD2 transgenic control group.The SOD2 transgenic control was superior to the wild-type control group in terms of improving cerebral blood flow and cerebral infarction(P<0.001).There were also no significant differences in cerebral blood flow and cerebral infarction volume between the wild-type fenofibrate group and the SOD2 transgenic control group and between the wild-type fenofibrate group and the SOD2 transgenic fenofibrate group.To conclude,the expression of SOD2 is one of the mechanisms of fenofibrate in the treatment of cerebral ischemia-reperfusion injury.
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BACKGROUND:Studies have found that activation of nuclear factor-erythroid 2-related factor 2/heme oxidase-1(Nrf2/HO-1)pathway can alleviate oxidative stress caused by cerebral ischemia-reperfusion injury,but whether human bone marrow mesenchymal stem cells(hBMSC)can activate Nrf2/HO-1 pathway to alleviate cerebral ischemia-reperfusion injury is still lacking relevant studies. OBJECTIVE:To investigate whether intracranial transplantation of hBMSC alleviates oxidative stress injury in cerebral ischemia-reperfusion animal models by activating Nrf2/HO-1 pathway. METHODS:Totally 40 male SPF SD rats were randomly divided into sham operation group,model group,hBMSC transplantation group,hBMSC+solvent group and hBMSC+Nrf2 inhibitor group.Each group consisted of eight animals.In the model group and the hBMSC transplantation group,middle cerebral artery occlusion model was prepared by thread embolization method.The thread embolization was removed 1 hour later,and 30 μL PBS or hBMSC cultured to at least passage 5 was injected into the right cortex and striatum of rats.In the hBMSC+Nrf2 inhibitor group and hBMSC+solvent group,the left ventricle was injected with Nrf2 inhibitor Brusatol and its solvent dimethyl sulfoxide respectively 24 hours before model establishment,then the middle cerebral artery occlusion model was prepared,and hBMSC was injected.Relevant indexes were detected 3 days after transplantation. RESULTS AND CONCLUSION:(1)CT and TTC staining showed the same area and volume of cerebral infarction:model group>hBMSC+Nrf2 inhibitor group>hBMSC+solvent group>hBMSC transplantation group>sham operation group.(2)Hematoxylin-eosin staining and Nissl's staining showed that the ischemic brain tissue was intact and the neurons were normal in the sham operation group.Compared with the model group,the pathological morphology and neuronal injury of the hBMSC transplantation group and the hBMSC+solvent group were significantly improved.Compared with the hBMSC+solvent group,the hBMSC+Nrf2 inhibitor group had more serious pathological morphology and neuronal damage.(3)Western blot assay and oxidative stress index detection results showed that compared with the sham operation group,Nrf2 and HO-1 proteins were decreased(all P<0.05),malondialdehyde was increased and superoxide dismutase was decreased(all P<0.05)in the model group.Compared with the model group,the expression levels of Nrf2 and HO-1 proteins were increased(all P<0.05),malondialdehyde was decreased and superoxide dismutase was increased(all P<0.05)in the hBMSC transplantation group and the hBMSC+solvent group.Compared with the hBMSC+solvent group,the expression levels of Nrf2 and HO-1 proteins were simultaneously decreased(all P<0.05),and malondialdehyde was increased and superoxide dismutase was decreased(all P<0.05)in the hBMSC+Nrf2 inhibitor group.(4)These results indicate that hBMSC can alleviate cerebral ischemia-reperfusion injury possibly by activating Nrf2/HO-1 pathway.
摘要
BACKGROUND:It was found that moxibustion can inhibit the inflammatory factors in the serum of rats with cerebral ischemia/reperfusion injury,resist oxidative stress,inhibit cell apoptosis,and effectively reduce cerebral ischemia/reperfusion injury. OBJECTIVE:To observe the effects of different moxibustion intervention time on the expression levels of nucleotide binding oligomerization domain-like protein 3 inflammasome(NLRP3),cysteine aspartase(caspase-1),apoptosis-related speck-like protein,exfoliatin-D protein,interleukin-1β and interleukin-18 in rats with cerebral ischemia/reperfusion injury,and to explore its action mechanism. METHODS:SD rats were randomly divided into sham operation group(n=9)and operation group(n=36).The model of focal cerebral ischemia/reperfusion injury was established by middle cerebral artery occlusion in the operation group.After successful modeling,the rats in the operation group were further divided into model group,moxibustion 10-minute group,moxibustion 15-minute group and moxibustion 30-minute group,with 9 rats in each group.Rats in the moxibustion 10-minute,15-minute and 30-minute groups were given moxibustion at"Baihui,Dazhui and Zusanli",respectively,once a day for a total of 7 days.The neurological deficits of rats were evaluated by LONGA method.The cerebral infarction was observed by 2,3,5-triphenyltetrazolium chloride staining.The pathological changes of brain tissue were observed by hematoxylin-eosin staining.The contents of interleukin-1β and interleukin-18 in serum of rats in each group were detected by ELISA.Immunohistochemistry and western blot assay were used to detect the expression levels of NLRP3,caspase-1,apoptosis-related spot-like protein and gasdermin D in the ischemic cortex of rats in each group. RESULTS AND CONCLUSION:Compared with the sham operation group,the neurological deficit score of the model group was significantly increased(P<0.01).Compared with the model group,the neurological deficit score of the moxibustion groups was significantly reduced(P<0.01).Compared with the sham operation group,the infarct volume of the model group was significantly increased(P<0.01).Compared with the model group,the infarct volume of the moxibustion groups was significantly reduced(P<0.01);the infarct volume of the rats was smallest in the moxibustion 30-minute group(P<0.05).Compared with the model group,the contents of inflammatory factors interleukin-1β and interleukin-18 in the serum of rats in the moxibustion groups were decreased(P<0.01).Compared with the moxibustion 10-minute group,the contents of inflammatory factors in the serum of rats in the moxibustion 30-minute group were significantly decreased(P<0.05).Compared with the model group,the expression of NLRP3,apoptosis-related spot-like protein,Caspase-1 and gasdermin D protein in the ischemic cortex of the moxibustion groups was significantly decreased(P<0.01).Compared with the moxibustion 10-minute and 15-minute groups,the expression of protein in the moxibustion 30-minute group was significantly decreased(P<0.05).It is concluded that moxibustion at Baihui,Dazhui and Zusanli can reduce cerebral ischemia/reperfusion injury,among which moxibustion for 30 minutes has the best effect,and its mechanism may be related to the inhibition of pyroptosis mediated by NLRP3/Caspase-1 pathway.
摘要
Cerebral ischemia-reperfusion is a serious cerebrovascular disease with high morbidity and mortality. In recent years， reperfusion therapy based on thrombolysis and thrombectomy has been the main treatment method for patients with ischemic stroke. Numerous studies have shown that Chinese medicine saponins can effectively interfere with cerebral ischemia-reperfusion in a multi-target and multi-way manner， which have great potential on the treatment and prevention of cerebral ischemia-reperfusion. Taking China National Knowledge Infrastructure （CNKI） literature database and Wanfang literature database as the analysis sources， this paper used SPSS statistics to summarize the number of papers on the treatment of cerebral ischemia-reperfusion with Chinese medicine saponins and CiteSpace to conduct cluster analysis on the high-frequency keywords of the research， thereby expounding the research hotspots and research status of Chinese medicine saponins in the treatment of cerebral ischemia-reperfusion. Based on literature analysis and summary of animal experiments on the treatment of cerebral ischemia-reperfusion with Chinese medicine saponins in the past two decades， Chinese medicine saponins exerted effects by anti-inflammation， inhibition of oxidative stress， immune regulation， protection of nerve cells， inhibition of thrombosis， promotion of thrombolysis， protection of mitochondria， blood-brain barrier repairing， and other ways. The specific mechanism， therapeutic effect， and signaling pathway of each Chinese medicine saponin have been summarized in this study， which provide a theoretical basis for the in-depth research， new drug development， and clinical application of Chinese medicine saponins for the treatment of cerebral ischemia- reperfusion.
摘要
This study explores the effect of total flavonoids of Rhododendra simsii(TFR) on middle cerebral artery occlusion(MCAO)-induced cerebral injury in rats and oxygen-glucose deprivation/reoxygenation(OGD/R) injury in PC12 cells and the underlying mechanism. The MCAO method was used to induce focal ischemic cerebral injury in rats. Male SD rats were randomized into sham group, model group, and TFR group. After MCAO, TFR(60 mg·kg~(-1)) was administered for 3 days. The content of tumor necrosis factor-α(TNF-α), interleukin-1(IL-1), and interleukin-6(IL-6) in serum was detected by enzyme-linked immunosorbent assay(ELISA). The pathological changes of brain tissue and cerebral infarction were observed based on hematoxylin and eosin(HE) staining and 2,3,5-triphenyltetrazolium chloride(TTC) staining. RT-qPCR and Western blot were used to detect the mRNA and protein levels of calcium release-activated calcium channel modulator 1(ORAI1), stromal interaction molecule 1(STIM1), stromal intera-ction molecule 2(STIM2), protein kinase B(PKB), and cysteinyl aspartate specific proteinase 3(caspase-3) in brain tissues. The OGD/R method was employed to induce injury in PC12 cells. Cells were randomized into the normal group, model group, gene silencing group, TFR(30 μg·mL~(-1)) group, and TFR(30 μg·mL~(-1))+gene overexpression plasmid group. Intracellular Ca~(2+) concentration and apoptosis rate of PC12 cells were measured by laser scanning confocal microscopy and flow cytometry. The effect of STIM-ORAI-regulated store-operated calcium entry(SOCE) pathway on TFR was explored based on gene silencing and gene overexpression techniques. The results showed that TFR significantly alleviated the histopathological damage of brains in MCAO rats after 3 days of admini-stration, reduced the contents of TNF-α, IL-1, and IL-6 in the serum, down-regulated the expression of ORAI1, STIM1, STIM2, and caspase-3 genes, and up-regulated the expression of PKB gene in brain tissues of MCAO rats. TFR significantly decreased OGD/R induced Ca~(2+) overload and apoptosis in PC12 cells. However, it induced TFR-like effect by ORAI1, STIM1 and STIM2 genes silencing. However, overexpression of these genes significantly blocked the effect of TFR in reducing Ca~(2+) overload and apoptosis in PC12 cells. In summary, in the early stage of focal cerebral ischemia-reperfusion injury and OGD/R-induced injury in PC12 cells TFR attenuates ischemic brain injury by inhibiting the STIM-ORAI-regulated SOCE pathway and reducing Ca~(2+) overload and inflammatory factor expression, and apoptosis.
Subject(s)
Animals , Male , Rats , Apoptosis , Brain Ischemia/metabolism , Caspase 3 , Interleukin-1 , Interleukin-6 , Rats, Sprague-Dawley , Reperfusion Injury/metabolism , Tumor Necrosis Factor-alpha/genetics , Flavonoids/pharmacology , Rhododendron/chemistry摘要
OBJECTIVE@#To study the protective effect of forsythiaside B (FB) against cerebral oxidative stress injury induced by cerebral ischemia/reperfusion (I/R) in mice and explore the underlying mechanism.@*METHODS@#Ninety C57BL/6 mice were randomized into sham-operated group, middle cerebral artery occlusion (MCAO) model group, and low-, medium and highdose (10, 20, and 40 mg/kg, respectively) FB groups. The expression levels of MDA, ROS, PCO, 8-OHdG, SOD, GSTα4, CAT and GPx in the brain tissue of the mice were detected using commercial kits, and those of AMPK, P-AMPK, DAF-16, FOXO3 and P-FOXO3 were detected with Western blotting. Compound C (CC), an AMPK inhibitor, was used to verify the role of the AMPK pathway in mediating the therapeutic effect of FB. In another 36 C57BL/6 mice randomized into 4 sham-operated group, MCAO model group, FB (40 mg/kg) treatment group, FB+CC (10 mg/kg) treatment group, TTC staining was used to examine the volume of cerebral infarcts, and the levels of ROS and SOD in the brain were detected; the changes in the protein expressions of AMPK, P-AMPK, DAF-16, FOXO3 and P-FOXO3 in the brain tissue were detected using Western blotting.@*RESULTS@#In mice with cerebral IR injury, treatment with FB significantly reduced the levels of ROS, MDA, PCO and 8-OHdG, increased the activities of antioxidant enzymes SOD, GSTα4, CAT and GPx, and enhanced phosphorylation of AMPK and FOXO3 and DAF-16 protein expression in the brain tissue (P < 0.01). Compared with FB treatment alone, the combined treatment with FB and CC significantly reduced phosphorylation of AMPK and FOXO3, lowered expression of DAF-16 and SOD activity, and increased cerebral infarction volume and ROS level in the brain tissue of the mice (P < 0.01).@*CONCLUSION@#FB inhibits oxidative stress injury caused by cerebral I/R in mice possibly by enhancing AMPK phosphorylation, promoting the downstream DAF-16 protein expression and FOXO3 phosphorylation, increasing the expression of antioxidant enzymes, and reducing ROS level in the brain tissue.
Subject(s)
Mice , Animals , AMP-Activated Protein Kinases/metabolism , Antioxidants/metabolism , Reactive Oxygen Species , Mice, Inbred C57BL , Brain Ischemia , Oxidative Stress , Infarction, Middle Cerebral Artery , Reperfusion Injury , Reperfusion , Superoxide Dismutase/metabolism摘要
OBJECTIVE@#To explore the mechanism that mediates the effect of soybean isoflavones (SI) against cerebral ischemia/reperfusion (I/R) injury in light of the regulation of regional cerebral blood flow (rCBF), ferroptosis, inflammatory response and blood-brain barrier (BBB) permeability.@*METHODS@#A total of 120 male SD rats were equally randomized into sham-operated group (Sham group), cerebral I/R injury group and SI pretreatment group (SI group). Focal cerebral I/R injury was induced in the latter two groups using a modified monofilament occlusion technique, and the intraoperative changes of real-time cerebral cortex blood flow were monitored using a laser Doppler flowmeter (LDF). The postoperative changes of cerebral pathological morphology and the ultrastructure of the neurons and the BBB were observed with optical and transmission electron microscopy. The neurological deficits of the rats was assessed, and the severities of cerebral infarction, brain edema and BBB disruption were quantified. The contents of Fe2+, GSH, MDA and MPO in the ischemic penumbra were determined with spectrophotometric tests. Serum levels of TNF-α and IL-1βwere analyzed using ELISA, and the expressions of GPX4, MMP-9 and occludin around the lesion were detected with Western blotting and immunohistochemistry.@*RESULTS@#The rCBF was sharply reduced in the rats in I/R group and SI group after successful insertion of the monofilament. Compared with those in Sham group, the rats in I/R group showed significantly increased neurological deficit scores, cerebral infarction volume, brain water content and Evans blue permeability (P < 0.01), decreased Fe2+ level, increased MDA level, decreased GSH content and GPX4 expression (P < 0.01), increased MPO content and serum levels of TNF-α and IL-1β (P < 0.01), increased MMP-9 expression and lowered occludin expression (P < 0.01). All these changes were significantly ameliorated in rats pretreated with IS prior to I/R injury (P < 0.05 or 0.01).@*CONCLUSION@#SI preconditioning reduces cerebral I/R injury in rats possibly by improving rCBF, inhibiting ferroptosis and inflammatory response and protecting the BBB.