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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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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.
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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.
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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.
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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.
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OBJECTIVE@#To improve the classical 4-vessel occlusion (4VO) model established by Pulsinelli and Brierley.@*METHODS@#Thirty-two male SD rats were randomized into sham operation group, I4VO-Con10 group, I4VO-Int10 group and I4VO-Int15 group. The sham surgery group underwent exposure of the bilateral vertebral arteries and carotid arteries without occlusion to block blood flow. The I4VO-Con10 group experienced continuous ischemia by occluding the bilateral vertebral arteries and carotid arteries for 10 minutes followed by reperfusion for 24 hours. The I4VO-Int10 and I4VO-Int15 groups were subjected to intermittent ischemia. The I4VO- Int10 group underwent 5 minutes of ischemia, followed by 5 minutes of reperfusion and another 5 minutes of ischemia, and then reperfusion for 24 hours. The I4VO-Int15 group experienced 5 minutes of ischemia followed by two cycles of 5 minutes of reperfusion and 5 minutes of ischemia, and then reperfusion for 24 hours. The regional cerebral blood flow (rCBF) was monitored with laser Doppler scanning, and survival of the rats was observed. HE staining was used to observe hippocampal pathologies to determine the optimal method for modeling. Another 48 rats were randomized into 6 groups, including a sham operation group and 5 model groups established using the optimal method. The 5 I4VO model groups were further divided based on the reperfusion time points (1, 3, 7, 14, and 28 days) into I4VO-D1, I4VO-D3, I4VO-D7, I4VO- D14, and I4VO- D28 groups. Body weight changes and survival of the rats were recorded. HE staining was used to observe morphological changes in the hippocampal, retinal and optic tract tissues. The Y-maze test and light/dark box test were used to evaluate cognitive and visual functions of the rats in I4VO-D28 group.@*RESULTS@#Occlusion for 5 min for 3 times at the interval of 5 min was the optimal method for 4VO modeling. In the latter 48 rats, the body weight was significantly lower than that of the sham-operated rats at 1, 3, 7, 14 and 28 days after modeling without significant difference in survival rate among the groups. The rats with intermittent vessel occlusion exhibited progressive deterioration of hippocampal neuronal injury and neuronal loss. Cognitive impairment was observed in the rats in I4VO-D28 group, but no obvious ischemic injury of the retina or the optic tract was detected.@*CONCLUSION@#The improved 4VO model can successfully mimic the main pathological processes of global cerebral ischemia-reperfusion injury without causing visual impairment in rats.
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Rats , Mâle , Animaux , Rat Sprague-Dawley , Encéphalopathie ischémique , Infarctus cérébral , Lésion d'ischémie-reperfusion , PoidsRésumé
Ischemic stroke is caused by a variety of factors caused by intracerebral artery stenosis or obstruction， can lead to cerebral ischemia， hypoxia， neuronal necrosis and neurological dysfunction and other pathological injuries， with high morbidity， high disability rate， high mortality characteristics. Cerebral ischemia-reperfusion injury is the main secondary injury， which can lead to permanent disability or even death in severe cases. With the development of traditional Chinese medicine（TCM） modernization， the extraction and application of active components of TCM have been paid more and more attention. Salidroside， as the main active component of Rhodirosea， a rare Chinese medicinal herb， has been proved to fight cerebral ischemia injury by inhibiting cell apoptosis， anti-oxidative stress， reducing inflammatory response， protecting blood-brain barrier， regulating autophagy， promoting nerve remodeling and synaptic regeneration in preclinical trials. However， due to its multi-pathway， multi-pathway and multi-target action characteristics， the specific mechanism of salidroside to improve cerebral ischemia injury has not been fully elucidated. By reviewing relevant literature in the past decade， the author reviewed the mechanism of action of salidroside in the treatment of ischemic brain injury， and summarized the recent progress of its pharmacokinetic studies and safety evaluation， in order to provide theoretical basis and new research ideas for the development and clinical application of the active ingredients of traditional Chinese medicine.
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The purpose of this study is to investigate whether chrysin reduces cerebral ischemia-reperfusion injury(CIRI) by inhi-biting ferroptosis in rats. Male SD rats were randomly divided into a sham group, a model group, high-, medium-, and low-dose chrysin groups(200, 100, and 50 mg·kg~(-1)), and a positive drug group(Ginaton, 21.6 mg·kg~(-1)). The CIRI model was induced in rats by transient middle cerebral artery occlusion(tMCAO). The indexes were evaluated and the samples were taken 24 h after the operation. The neurological deficit score was used to detect neurological function. The 2,3,5-triphenyl tetrazolium chloride(TTC) staining was used to detect the cerebral infarction area. Hematoxylin-eosin(HE) staining and Nissl staining were used to observe the morphological structure of brain tissues. Prussian blue staining was used to observe the iron accumulation in the brain. Total iron, lipid pero-xide, and malondialdehyde in serum and brain tissues were detected by biochemical reagents. Real-time quantitative polymerase chain reaction(RT-qPCR), immunohistochemistry, and Western blot were used to detect mRNA and protein expression of solute carrier fa-mily 7 member 11(SLC7A11), transferrin receptor 1(TFR1), glutathione peroxidase 4(GPX4), acyl-CoA synthetase long chain family member 4(ACSL4), and prostaglandin-endoperoxide synthase 2(PTGS2) in brain tissues. Compared with the model group, the groups with drug intervention showed restored neurological function, decreased cerebral infarction rate, and alleviated pathological changes. The low-dose chrysin group was selected as the optimal dosing group. Compared with the model group, the chrysin groups showed reduced content of total iron, lipid peroxide, and malondialdehyde in brain tissues and serum, increased mRNA and protein expression levels of SLC7A11 and GPX4, and decreased mRNA and protein expression levels of TFR1, PTGS2, and ACSL4. Chrysin may regulate iron metabolism via regulating the related targets of ferroptosis and inhibit neuronal ferroptosis induced by CIRI.
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Rats , Mâle , Animaux , Rat Sprague-Dawley , Ferroptose , Transduction du signal , Encéphalopathie ischémique/métabolisme , Cyclooxygenase 2/métabolisme , ARN messager , Infarctus cérébral , Lésion d'ischémie-reperfusion/métabolisme , Malonaldéhyde , Infarctus du territoire de l'artère cérébrale moyenneRésumé
Based on GC-MS and network pharmacology, the active constituents, potential targets, and mechanism of essential oil from Gleditsiae Fructus Abnormalis(EOGFA) against cerebral ischemia/reperfusion(I/R) injury were explored, and the effective constituents were verified by experiment. To be specific, GC-MS was used identify the constituents of the volatile oil. Secondly, the targets of the constituents and disease were predicted by network pharmacology, and the drug-constituent-target network was constructed, followed by Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment of the core targets. Molecular docking was performed to investigate the binding affinity between the active constituents and the targets. Finally, SD rats were used for experimental verification. The I/R injury model was established, and the neurological behavior score, infarct volume, and pathological morphology of brain tissue were measured in each group. The content of interleukin-1β(IL-1β), interleukin-6(IL-6), and tumor necrosis factor-alpha(TNF-α) was determined by enzyme-linked immunosorbent assay(ELISA), and the protein expression of vascular endothelial growth factor(VEGF) by Western blot. A total of 22 active constituents and 17 core targets were screened out. The core targets were involved in 56 GO terms and the major KEGG pathways of TNF signaling pathway, VEGF signaling pathway, and sphingolipid signaling pathway. Molecular docking showed that the active constituents had high affinity to the targets. The results of animal experiment suggested that EOGFA can alleviate the neurological impairment, decrease the cerebral infarct volume and the content of IL-1β, IL-6 and TNF-α, and down-regulate the expression of VEGF. The experiment verified the part results of network pharmacology. This study reflects the multi-component, multi-target, and multi-pathway characteristics of EOGFA. The mechanism of its active constituents is related to TNF and VEGF pathways, which provides a new direction for in-depth research on and secondary development of Gleditsiae Fructus Abnormalis.
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Animaux , Rats , Rat Sprague-Dawley , Pharmacologie des réseaux , Huile essentielle , Chromatographie gazeuse-spectrométrie de masse , Interleukine-6 , Simulation de docking moléculaire , Facteur de nécrose tumorale alpha , Facteur de croissance endothéliale vasculaire de type A , Lésion d'ischémie-reperfusion , Infarctus cérébralRésumé
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.
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Animaux , Mâle , Rats , Apoptose , Encéphalopathie ischémique/métabolisme , Caspase-3 , Interleukine-1 , Interleukine-6 , Rat Sprague-Dawley , Lésion d'ischémie-reperfusion/métabolisme , Facteur de nécrose tumorale alpha/génétique , Flavonoïdes/pharmacologie , Rhododendron/composition chimiqueRésumé
ObjectiveTo investigate the effects of Buyang Huanwutang （BYWHT） on reducing inflammatory injury and improving neurological function after cerebral ischemia-reperfusion in rats via activating the adiponectin （APN） pathway. MethodMale SD rats were randomized into sham， model， BYHWT （16 g·kg-1， twice a day）， and BYHWT + APN inhibitor （GW9662） groups. In the sham group， blood vessels were isolated. The rat model of middle cerebral artery occlusion （MCAO） was established. The rats in the BYHWT+GW9662 group was treated with subcutaneous injection of GW9662 at 4 m·kg-1 30 min before MCAO surgery and BYHWT at 16 g·kg-1 by gavage after MCAO surgery， once in the morning and once in the evening. The immunofluorescence （IF） assay was employed to observe the expression of adiponectin receptor 1 （AdipoR1） and the colocalization of AdipoR1 with neuronal nuclei （NeuN） and ionized calcium binding adaptor molecule 1 （Iba1） in the brain. Enzyme-linked immunosorbent assay （ELISA） was employed to detect the expression of APN in the serum and brain. The balance beam test was carried out to examine the balance ability， and the grasping test to assess the recovery of limb strength. The immunofluorescence assay was used to detect the expression of myeloperoxidase （MPO）. Western blot was employed to determine the expression of tumor necrosis factor-alpha （TNF-α）， interleukin （IL）-1β， IL-6， and IL-10 and in the brain. ResultCompared with the sham group， the modeling promoted the expression of AdipoR1 （P<0.01）， lowered the APN levels in the serum and brain （P<0.05， P<0.01）， increased the score in the balance beam test （P<0.01）， and decreased the grasping strength of forepaw （P<0.01）， which were accompanied with increased MPO， TNF-α， IL-1β， and IL-6 levels （P<0.01） and decreased IL-10 level （P<0.01）. Compared with the model group， BYHWT promoted the expression of AdipoR1 （P<0.01）， elevated APN levels in the serum and brain （P<0.05， P<0.01）， and increased the grasping strength of forepaw （P<0.01）， which were accompanied with lowered MPO， TNF-α， IL-1β， and IL-6 levels （P<0.01） and elevated IL-10 level （P<0.01）. All the above effects were partially blocked by GW9662. ConclusionBYHWT can reduce inflammatory injury and improve neurological function in the rat model of cerebral ischemia-reperfusion by activating the APN pathway.
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Objective:To explore the mechanism of gypenoside ⅩⅦ against cerebral ischemia/reperfusion (I/R) through nuclear factor erythroid 2-related factor 2/antioxidant responsive element (Nrf2/ARE) signaling pathway.Methods:Forty SPF Sprague Dawley (SD) rats were randomly divided into sham operated group, I/R model group, 25, 50 and 100 mg/kg gypenoside ⅩⅦ groups ( n = 8). Gypenoside ⅩⅦ groups were administered 25, 50 or 100 mg/kg (0.01 mL/g) gypenoside ⅩⅦ by intragastric administration for 14 days; the other two groups received the same dose of saline. Rat cerebral I/R model was established by modified line bolt method; rats in the sham operated group underwent the same procedure without producing substantial embolization. After 24 hours of reperfusion, the neurological deficit scores of the rats in each group were assessed. Rat abdominal aortic whole blood was collected and the serum reactive oxygen species (ROS), heme oxygenase-1 (HO-1), γ-glutamylcysteine synthase (γ-GCS), superoxide dismutase (SOD), quinone NADH oxidoreductase 1 (NQO1), and malondialdehyde (MDA) were detected. Then whole brain tissue was harvested and penumbra tissue was isolated from cerebral cortex, the general condition of rat brain tissue and the volume of cerebral infarction were evaluated, the histopathological changes in the brain were observed under light microscopy, the mRNA expressions of Nrf2 and Keap1 were measured by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR), the protein expressions of Nrf2 and Keap1 were determined by Western blotting. Results:After 24 hours of reperfusion, compared with the sham operated group, the score of neurological deficit and infarct volume were significantly increased, the NQO1, SOD and γ-GCS levels in serum were significantly decreased, MDA, HO-1 and ROS levels in serum were significantly increased, the Nrf2 and Keap1 mRNA and protein expressions in the ischemic penumbra were significantly increased in rats from I/R model group. Compared with the I/R model group, the neurological deficit scores (1.50±0.53, 1.37±0.52 vs. 2.75±0.46) and brain infarct volume [(19.8±5.1)%, (21.4±6.4)% vs. (42.3±5.8)%] were significantly reduced, serum NQO1, SOD, HO-1 and γ-GCS were significantly increased [NQO1 (ng/L): 186.05±10.38, 220.75±16.22 vs. 131.36±5.95, SOD (kU/L): 63.23±5.30, 72.70±8.62 vs. 36.75±6.55, HO-1 (ng/L): 60.57±7.93, 60.35±4.72 vs. 42.72±4.95, γ-GCS (kU/L): 8.81±0.53, 8.72±0.69 vs. 6.80±0.56], serum MDA and ROS levels were significantly reduced [MDA (μmol/L): 5.94±0.66, 5.61±0.53 vs. 10.88±1.34, ROS (kU/L): 69.11±4.23, 67.12±4.52 vs. 104.43±7.54], the mRNA and protein expressions of Nrf2 and Keap1 in the ischemic penumbra were significantly increased in rats from 50 mg/kg and 100 mg/kg gypenoside ⅩⅦ groups [Nrf2 mRNA (2 -△△Ct): 1.90±0.13, 2.13±0.18 vs. 1.48±0.11, Keap1 mRNA (2 -△△Ct): 1.78±0.11, 1.85±0.10 vs. 1.43±0.10, Nrf2/β-actin: 0.73±0.04, 0.79±0.03 vs. 0.60±0.03, Keap1/β-actin: 0.71±0.01, 0.76±0.03 vs. 0.61±0.01], all the comparative differences were statistically significant (all P < 0.01); 25 mg/kg gypenoside ⅩⅦ had no significant effect. Conclusion:Gypenoside ⅩⅦ (50 mg/kg and 100 mg/kg) may play a role in anti-cerebral I/R injury by regulating NQO1, SOD, HO-1, γ-GCS, ROS and MDA through Nrf2/ARE signaling pathway.
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Objective To detecte the expressions of phosphorylated p38 MAPK (p-p38 MAPK), Bax and Bcl-2 in the cerebral cortex of hyperlipidemia rats after cerebral ischemia-reperfusion (I/R) injury and the effect of SB203580 on the expressions of p-p38 MAPK, Bax and Bcl-2, to explore the effect of p38 MAPK activation on the expressions of Bax and Bcl-2 in hyperlipidemia cerebral I/R injury. Methods After the hyperlipidemia model was established, the rats were randomly divided into 3 groups: sham operation group, operation group (I/R) and SB203580 treatment group (SB+I/R), with 10 rats in each group. The focal cerebral I/R model in hyperlipemia rats was established with thread embolism of the left middle cerebral artery. The neurobehavioral score was used to observe the symptoms of neurobehavioral injury. The 2, 3, 5-triphenyltetrazolium chloride (TTC) staining was used to detect the volume of cerebral infarction, and the TUNEL staining was used to observe apoptotic cells. The relative expression levels of p-p38 MAPK, Bax and Bcl-2 were analyzed by immunohistochemistry. Results Compared with the sham group, the infarct volume, apoptosis index and neurobehavioral score of rats in the I/R group increased significantly, and the expressions of p-p38 MAPK and Bax increased significantly, and the expression of Bcl-2 decreased significantly (P<0. 05). Compared with the I/R group, rats in the SB+I/R group had less brain damage, the infarct volume and the apoptosis index were significantly reduced, the expressions of p-p38 MAPK reduced significantly, Bax expression decreased while Bcl-2 expression increased. The differences were statistically significant (P<0. 05). Neurobehavioral scores were lower in SB+I/R group than in I/R group, but the difference was not statistically significant. Conclusion In the process of cerebral I/R injury in hyperlipidemiarats, activation of p38 MAPK can regulate the expression of Bax and Bcl-2.
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Objective To observe the effect of polyinosinic-polycytidylic acid ( Poly-IC ) treatment on the expressions of Bcl-2 and Bax after cerebral ischemia-reperfusion ( I / R ) injury in fryperlipidemia rats, and to detect the cerebral infarction, blood-brain barrier permeability and behavioral injury symptoms, to explore the neuroprotective effect of Poly-IC treatment on cerebral I /R injury in fryperlipidemia rats. Methods Hyperlipidemia rats were randomly divided into cerebral I /R group, Poly-IC pretreatment group, Poly-IC post-treatment group and sham operation group, 20 rats in each group. Neurobehavioral performance of rats in each group was recorded according to neurobehavioral score of 0-4 points. Blood-brain barrier permeability of rats in each group was detected by Evans blue staining. TTC staining was used to observe the cerebral infarction in each group. Apoptotic cells in the cerebral cortex of rats in each group was observed by TUNEL staining. The relative expression levels of Bcl-2 and Bax were determined by Western blotting. Results Compared with the sham group, the symptoms of neurobehavioral damage in the I/R group were serious and the score increased significantly (P<0. 05). The scores of Poly-IC pretreatment and post-treatment groups were significantly lower than that of I/R group (P<0. 05). Evans blue staining result showed that the blood-brain barrier permeability of the I/R group was significantly higher than that of the sham group (P<0. 05) , and Poly-IC pretreatment or post-treatment could significantly reduce the blood-brain barrier permeability ( P < 0. 05 ) . No infarct was observed in the sham group with uniform red staining, while white infarct was observed in the brain tissue of the I/R group. Compared with the I/R group, the volume of infarct in both Poly-IC pretreatment and post-treatment groups reduced significantly (P<0. 05). The apoptosis index in cerebral cortex of rats in I/R group was significantly higher than that in sham group ( P < 0 .05 ) , while the apoptosis index in Poly-IC pretreatment or post-treatment group was significantly lower than that in I/R group(P<0. 05 ) . The result of Western blotting showed that, compared with the sham group, the expression of Bax in the I/R group was significantly increased(P<0. 05) , the expression of Bcl-2 was significantly decreased(P<0. 05). Compared with the I/R group, the expression of Bax in the Poly-IC pretreatment or post-treatment group reduced significantly ( P < 0. 05 ) , the expression of Bcl-2 increased significantly(P<0. 05). Conclusion Poly-IC pretreatment or post-treatment can improve the symptoms of neurobehavioral injury, reduce the damage of blood-brain barrier, reduce the volume of cerebral infarction, decrease the apoptosis index of nerve cells, play a neuroprotective effect on cerebral ischemia reperfusion injury in rats with hyperlipidemia, and this protective effect may be related to the change of Bcl-2 and Bax expression levels.
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Aim To investigate the effects of total flavonoids from Rosa rugosa (TFR) on cerebral ischemia reperfusion injury (CIRI) in rats, and to investigate whether TFR inhibited neuronal apoptosis by regulating phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signaling pathway and endoplasmic reticulum stress (ERS) pathways. Methods SD rats were randomly divided into sham operation group, model group, low-dose group (50 mg · kg
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Aim To explore the effect of Buyang Huanwu Decoction on cerebral ischemia-reperfusion injury in rats by regulating autophagy through PI3K/AKT pathway. Methods The rats were randomly divided into five groups(n=10): sham operation group(Sham), model group(Model), Buyang Huanwu Decoction group(BYHWD), PI3K inhibitor group(LY294002)and Vehicle group(Vehicle). Except Sham group, the other groups were treated with 2h ischemia and 72 h reperfusion for modeling. The Zea Longa score was used to assess the neurological defects, HE was used to observe brain injury in the ischemic penumbra(IP), immunofluorescence was employed to detect LC3, and Western blot was used to detect pathway and autophagy marker proteins. Results Compared BYHWD group with model group, the neurological score of rats decreased, cerebral infarction volume decreased, the pathological lesions of brain IP were relieved, PI3K and p-AKT/AKT expression increased, and LC3Ⅱ/ decreased and p62 increased(P<0.05). The regulatory effect of BYHWD was weakened by LY294002(P<0.05). Conclusion Buyang Huanwu Decoction alleviates cerebral ischemia-reperfusion injury in rats by activating PI3K/AKT pathway to inhibit autophagy.
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Aim To explore the inhibitory effect of Buyang Huanwu Decoction on the inflammatory response in the hippocampus of brain tissues of CIRI rats by regulating SIRT1 and the underlying mechanism. Methods The middle cerebral artery embolization (MCAO) model was prepared in rats and divided into sham operation group (Sham), model group (MCAO/R), Buyang Huanwu Decoction group (BYHWT),and BYHWT + SIRT1 inhibitor group (BYHWT + EX527). Zea Longa was used to detect the neurological function score of rats in each group; TTC staining was used to determine the volume of cerebral infarction; HE staining was used to observe the pathological damage of the hippocampus; Western blot was used to detect the expression levels of SIRT1 and IL-6; immunohistochemistry was used to detect TNF-α, IL-1β expression level. Results Compared with the sham group,the neurological function score of the MCAO/R group increased (P < 0.05); the volume of cerebral infarction increased (P < 0.05); the nerve cells in hippocampus were severely damaged, arranged disorderly, and the nucleus was broken; Western blot showed that the expression of SIRT1 decreased, IL-6 expression increased (P <0.05); immunohistochemistry showed that TNF-α,IL-1β expression increased (P < 0.05). Compared with the MCAO/R group, the neurological function score of the BYHWT group decreased (P <0.05); the volume of cerebral infarction decreased (P < 0.05); the damage of nerve cells in hippocampus was reduced; Western blot showed that the expression of SIRT1 increased and IL-6 expression decreased (P < 0.05); immunohistochemistry showed that TNF-α, IL-1β expression decreased (P < 0.05). Compared with the BYHWT group, the neurological function score of the BYHWT + EX527 group increased (P < 0.05); the volume of cerebral infarction was raised (P <0.05); the damage of nerve cells in hippocampus was aggravated; Western blot showed that the expression of SIRT1 decreased and IL-6 expression increased (P < 0.05); immunohistochemistry showed that TNF-α, IL-1β expression increased (P < 0.05). Conclusions Preliminary discussion of Buyang Huanwu Decoction can activate SIRT1 in hippocampus of rat brain tissues to reduce the inflammatory response after CIRI and play a role in brain protection.
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OBJECTIVE@#To observe the effects of Xingnao Kaiqiao (regaining consciousness and opening orifices) acupuncture therapy on the expression of hypoxia-inducible factor 1α (HIF-1α) and Nod-like receptor protein 3 (NLRP3) in cerebral ischemia-reperfusion rats, and to explore the mechanism of acupuncture against cerebral ischemia-reperfusion injury.@*METHODS@#Seventy-two male SD rats were randomly divided into a sham-operation group, a model group, an acupuncture group and a non-point acupuncture group, with 18 rats in each one. Using modified Longa thread embolization method, the rat model of acute focal cerebral ischemia was prepared; and after 2 h ischemia, the reperfusion was performed to prepared the model of cerebral ischemia-reperfusion. Immediately after reperfusion, Xingnao Kaiqiao acupuncture method was applied to bilateral "Neiguan" (PC 6) and "Shuigou" (GV 26) in the acupuncture group, while in the non-point acupuncture group, acupuncture was delivered at non-points and all of the needles were retained for 30 min in these two groups. The samples were collected 24 h after reperfusion in the rats of each group. Zea-Longa neurological deficit score was used to evaluate the degree of cerebral neurological impairment, TTC staining was adopted to observe the volume percentage of cerebral infarction, HE staining was provided to observe the morphological changes of brain, and Western blot was applied for detecting the expression of HIF-1α and NLRP3 proteins in the cerebral cortex on the right side.@*RESULTS@#Compared with the sham-operation group, neurological deficit score and volume percentage of cerebral infarction were increased in the model group (P<0.01), and HIF-1α and NLRP3 protein expression was elevated (P<0.01). Compared with the model group, neurological deficit score and volume percentage of cerebral infarction were decreased (P<0.01), and HIF-1α and NLRP3 protein expression was lower (P<0.01) in the acupuncture group. There was no significant difference in above indexes in the non-point acupuncture group compared with the model group (P>0.05). Compared with the sham-operation group, the brain tissue of the rats in the model group and the non-point acupuncture group was loose and edema, and the nuclei were shriveled. The brain tissue morphology in the acupuncture group was similar to that of the sham-operation group.@*CONCLUSION@#Acupuncture can alleviate cerebral ischemia-reperfusion injury, and its mechanism may be related to the regulation of HIF-1α/NLRP3 signaling pathway to attenuate inflammatory response.
Sujets)
Mâle , Animaux , Rats , Rat Sprague-Dawley , Protéine-3 de la famille des NLR contenant un domaine pyrine/génétique , Thérapie par acupuncture , Lésion d'ischémie-reperfusion/thérapie , Encéphalopathie ischémique/thérapie , Infarctus cérébral/thérapie , Protéines NLRRésumé
@#ObjectiveTo explore the protective effect of Sox11 gene on cerebral ischemia reperfusion injury(CIRI)in mice and its mechanism,so as to provide a new target for the treatment of CIRI.MethodsThe mouse middle cerebral artery occlusion(MCAO)model and Neuro2A cell oxygen glucose deprivation reperfusion(OGDR)model were established and detected for the temporal and spatial distribution of Sox11 in the models by real-time quantitative PCR,Western blot,immunohistochemistry(IHC)and immunohistofluorescence(IHF).The altered expression of some crucial genes in the pathway of apoptosis and inflammation in OGDR model after the disruption of Sox11 expression was detected by Western blot.ResultsThe expression level of Sox11 mRNA and protein increased significantly in both MCAO and Neuro2A OGDR models(P = 0.000 1 ～ 0.038 8);After CIRI,Sox11 expression was elevated in the hippocampal dentate gyrus(DG)region of mice;After interfering with the expression of Sox11 in OGDR model,the expression of apoptosis-related protein Cleaved Caspase 3 significantly increased,while the expression of anti-apoptosis protein Bcl-2 significantly decreased,and the expression of phosphorylated NF-κB(p-NF-κB)protein related to inflammatory reaction also up-regulated significantly.Conclusion Sox11gene had a protective effect against CIRI in mice,and was involved in the regulation of apoptosis and inflammation pathways after CIRI.
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ObjectiveTo investigate the effects of dopamine receptor agonist pramipexole and levodopa on emotion and cognition, and mitochondrial membrane potential of rats after global cerebral ischemia-reperfusion injury. MethodsA total of 80 male Sprague-Dawley rats were divided into sham group (n = 20), model group (n = 20), pramipexole group (n = 20) and combined group (n = 20). The latter three groups were used to prepare the model of global cerebral ischemia-reperfusion injury with Pulsinelli's four-vessel occlusion. The pramipexole group was intraperitoneally injected pramipexole 0.5 mg/kg once a day, while the combined group was injected levodopa 50 mg/kg and pramipexole 0.5 mg/kg, for 14 days. Five rats in each group were tested with open field test three, seven and 14 days after modeling; five were tested with Y-maze test seven and 14 days after modeling; five were detected mitochondrial membrane potential three, seven and 14 days after modeling; and five were observed under Nissl's staining14 days after modeling. ResultsCompared with the model group, the number of entries into the central zone (P < 0.05), total distance travelled (P < 0.05) and average velocity (P < 0.05) in the open field test increased in the pramipexole and combined groups seven and 14 days after modeling, duration spent in the central zone increased in the pramipexole and combined groups seven days after modeling (P < 0.05); the rate of spontaneous alternation of Y-maze test increased in the pramipexole and combined groups 14 days after modeling (P < 0.05); mitochondrial membrane potential in hippocampus increased in the pramipexole and combined groups seven and 14 days after modeling (P < 0.05), and it was less in the pramipexole group than in the combined group 14 days after modeling (P < 0.05); and the number of surviving neurons in the hippocampal CA1 increased in the pramipexole and combined groups 14 days after modeling (P < 0.05). ConclusionPramipexole may improve emotion and cognition of rats after global cerebral ischemia-reperfusion injury, and it may be helpful for restoring mitochondrial membrane potential as combining with levodopa.