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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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Aim To investigate the effect of Buyang Huanwu decoction on the expression of silencing regulation factor 1(SIRT1)protein in cortical area and the possible mechanism of cerebral ischemia/reperfusion injury(CIRI)via establishing middle cerebral artery occlusion(MCAO)model. Methods SD rats were randomly divided into sham group(Sham), model group(MCAO/R), Buyang huanwu decoction group(BYHWT), and atorvastatin group(Atorvastatin), with 15 rats in each group. After 2 h ischemia/reperfusion for 72 h and drug intervention, the model was successfully constructed by using laser speckle blood flow monitoring video system. Zea Longa neurological function score was used to evaluate the neurological defects of rats after modeling. TTC staining was used to detect infarct volume. Nissl staining was used to observe the injury of nerve cells. Western blot was employed to detect the SIRT1 protein expression level. Immunofluorescence was applied to detect the fluorescence expression of SIRT1. Results Compared with sham group, the neurological deficits of MCAO/R group were serious(P<0.05). Cerebral infarction volume increased(P<0.05). The nerve cells were severely damaged, disordered, with the nucleus pyknosis(P<0.05). SIRT1 protein expression was reduced(P<0.05). The fluorescence intensity of SIRT1 decreased(P<0.05). Compared with MCAO/R group, the neurological impairment degree of rats in BYHWT and Atorvastatin groups was reduced(P<0.05). The proportion of cerebral infarction volume decreased(P<0.05). The injury of nerve cells was significantly reduced and the number of nerve cells increased(P<0.05). The expression of SIRT1 protein was up-regulated(P<0.05). Fluorescence intensity of SIRT1 increased(P<0.05). Conclusions Buyang huanwu decoction can effectively alleviate brain injury in cerebral ischemia/reperfusion rats, and its protective effect may be related to the increase of SIRT1 protein expression in the ischemic cortical region.
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Aim To explore the mechanism of Buyang huanwu decoction attenuating cerebral ischemia-reper- fusion injury in rats by regulating autophagv through AMPK/mTOR/ULKl signaling pathway.Methods Left eerebral ischemia model in rats was established by modified thread ocelusion method, then the rats in each group were given medieine onee every 24 hours for 3 times.After 72 hours of reperfusion, the nerve injury and the changes of cerebral infarction volume were observed; the morphology, number and apoptosis of nerve cells were observed by Nissl staining and TUNEL staining; the expression of autophagy protein and AMPK/mTOR/LJLKl autophagy signaling pathway related proteins were detected by Western blot.Results Buyang huanwu decoction could improve the neurological deficit of rats, reduce the volume of cere bral infarction and neuronal apoptosis, reduce the pathological injury of brain tissues, inhibit the phosphorylation activation of AMPK, relieve the inhibition of AMPK on downstream mTOR and LJLK1 , promote the phosphorylation activation of both, and inhibit autophagy.AMPK agonist metformin increased the level of autophagy and reversed the protective effect of Buyang huanwu decoction on cerebral ischemia-reperfusion injury in rats.Conclusion Buyang huanwu decoction mediates AMPK/mTOR/ULKl autophagy signaling pathway to play a neuroprotective effect on cerebral is- chemia-reperfusion injury in rats.
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Alzheimer's disease(AD) patients in China have been surging, and the resultant medical burden and care demand have a huge impact on the development of individuals, families, and the society. The active component compound of Epimedii Folium, Astragali Radix, and Puerariae Lobatae Radix(YHG) can regulate the expression of iron metabolism-related proteins to inhibit brain iron overload and relieve hypofunction of central nervous system in AD patients. Hepcidin is an important target regulating iron metabolism. This study investigated the effect of YHG on the expression of a disintegrin and metalloprotease-17(ADAM17), a key enzyme in the hydrolysis of β amyloid precursor protein(APP) in HT22 cells, by mediating hepcidin. To be specific, HT22 cells were cultured in vitro, followed by liposome-mediated siRNA transfection to silence the expression of hepcidin. Real-time PCR and Western blot were performed to examine the silencing result and the effect of YHG on hepcidin in AD cell model. HT22 cells were randomized into 7 groups: control group, Aβ25-35 induction(Aβ) group, hepcidin-siRNA(siRNA) group, Aβ25-35 + hepcidin-siRNA(Aβ + siRNA) group, Aβ25-35+YHG(Aβ+YHG) group, hepcidin-siRNA+YHG(siRNA+YHG) group, Aβ25-35+hepcidin-siRNA+YHG(Aβ+siRNA+YHG) group. The expression of ADAM17 mRNA in cells was detected by real-time PCR, and the expression of ADAM17 protein by immunofluorescence and Western blot. Immunofluorescence showed that the ADAM17 protein expression was lower in the Aβ group, siRNA group, and Aβ+siRNA group than in the control group(P<0.05) and the expression was lower in the Aβ+siRNA group(P<0.05) and higher in the Aβ+YHG group(P<0.05) than in the Aβ group. Moreover, the ADAM17 protein expression was lower in the Aβ+siRNA group(P<0.05) and higher in the siRNA+YHG group(P< 0.05) than in the siRNA group. The expression was higher in the Aβ+siRNA+YHG group than in the Aβ+siRNA group(P<0.05). The results of Western blot and real-time PCR were consistent with those of immunofluorescence. The experiment showed that YHG induced hepcidin to up-regulate the expression of ADAM17 in AD cell model and promote the activation of non-starch metabolic pathways, which might be the internal mechanism of YHG in preventing and treating AD.
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Humanos , Proteína ADAM17 , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , Medicamentos de Ervas Chinesas/farmacologia , Hepcidinas/genética , PuerariaRESUMO
Objective To investigate the effect of calycosin on cerebral ischemia/reperfusion injury and its mechanism. Methods Forty SPF male SD rats were randomly divided into sham group, model group, calycosin group (20 mg/kg), nimodipine group (0.7 mg/kg, positive control group). The occlusion model of middle cerebral artery in rats was established by modified thread occlusion method, and the environment of cerebral ischemia-reperfusion injury was simulated in vivo. Zea longa score was used to detect the neurological deficit of rats after ischemia-reperfusion injury, 2, 3, 5-triphenyltetranitrogen (TTC) was used to detect the volume of cerebral infarction, HE staining was used to detect the pathomorphological changes of nerve cells, Nissl staining was used to observe the changes of nissl bodies, TUNEL staining was used to detect the apoptosis of nerve cells, Western blotting was used to detect the expression of cytochrome C (Cyt C), apoptotic protease activating factor-1 (Apaf-1), Caspase-9 and Caspase-3. Results Compared with the sham group, the neurological deficit symptoms in the model group were significant (P<0.05), the volume of cerebral infarction increased significantly (P<0.05). Under the microscope, it was found that the nerve cells showed contraction of cell body, hyperchromatic and pyknosis of nucleus and poor growth state, the expression of nissl body reduced significantly (P < 0.05), the apoptotic nerve increased significantly (P< 0.05), the expression of Cyt C, Apaf-1, Caspase-9 and Caspase-3 increased significantly (P<0.05). Compared with the model group, the neurological deficit symptoms of calycosin group and nimodipine group reduced significantly (P<0.05), the volume of cerebral infarction reduced significantly (P<0.05). Under the microscope, the damage of nerve cells reduced significantly, the expression of nissl body increased significantly (P<0.05), the apoptotic nerve reduced significantly (P<0.05), the expression of Cyt C, Apaf-1, Caspase-9 and Caspase-3 decreased significantly (P<0.05). Conclusion Calycosin can significantly inhibit the apoptosis of nerve cells and reduce the cerebral ischemia-reperfusion injury. Its mechanism of action is related to the effective regulation of Cyt C/Apaf-1 apoptosis signaling pathway by calycosin.
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Objective To investigate the effect of calycosin on mitochondrial apoptotic pathway in oxygen-glucose deprivation/ reoxygenation PC12 cells. Methods PC12 cells were randomly divided into four groups: control group, model group, calycosin group and nimodipine group. Except for the control group, the other groups were treated with oxygen and glucose deprivation for 2 hours and compound oxygen and glucose for 24 hours. Calycosin group and nimodipine group were treated with drug-containing medium containing calycosin (0. 07 μmol/ L) and nimodipine (5. 00 μmol/ L) simultaneously with reoxygenation. CCK-8 method was used to detect cell survival rate, flow cytometry was used to detect cell apoptosis rate, immunofluorescence method was used to detect Bax/ Bcl-2 ratio, Western blotting was used to detect the expression of key proteins cytochrome C (Cyt-C), apoptotic protease activating factor-1 (Apaf-1) and Caspase-3 in mitochondrial apoptotic pathway. Results Compared with the control group, the survival rate of cells in model group decreased significantly (P<0. 05), and the apoptotic rate increased significantly (P<0. 05), the ratio of Bax/ Bcl-2 was significantly increased (P<0. 05), and the expression of key proteins Cyt-C, Apaf-1 and Caspase-3 in mitochondrial apoptotic pathway were significantly increased (P<0. 05). Compared with the model group, the cell survival rates of calycosin group and nimodipine group increased significantly (P < 0. 05), apoptotic rate decreased significantly (P<0. 05), the ratio of Bax/ Bcl-2 was significantly decreased (P<0. 05), and the expression of key proteins of mitochondrial apoptotic pathway, Cyt-C, Apaf-1 and Caspase-3 were significantly decreased (P < 0. 05). The difference has statistical significance. Conclusion Calycosin can significantly improve the survival rate of oxygen-glucose deprivation/ reoxygenation PC12 cells and inhibit cell apoptosis. Its mechanism is closely related to the inhibition of the expression of key proteins Cyt-C, Apaf-1 and Caspase-3 in mitochondrial apoptotic pathway by calycosin.
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Objective::To observe the effect of modified Dihuang Yinzi on the learning and memory ability and on the neurons in CA1 area of hippocampus of rats suffering from vascular dementia. Method::The 84 male SD rats were randomly selected to form the sham operation group of 12 rats, and the other 72 rats were chosen for the vascular dementia model by means of Bivascular occlusion, and among which 60 were chosen randomly into 6 groups of 12 rats, namely, the model group, the nimodipine group (0.011 g·kg-1), and the high, medium and low dose modified Dihuang Yinzi (4.54, 2.27, 1.14 g·kg-1) respectively. After 30 days of continuous gavage, Morris water maze was used to detect the learning and memory ability of rats, hematoxylin eosin (HE) was used to observe the morphological changes of hippocampal CA1 neurons, transmission electron microscopy was used to observe the ultrastructural changes of hippocampal CA1 neurons, TUNEL was used to detect the apoptosis level of hippocampal CA1 neurons, immunohistochemical(IHC) was used to detect the expression level of phosphatidylinositol-3(PI3K), protein kinase B (Akt), Caspase-3 in hippocampal CA1 tissues. Result::Compared with sham operation group, the escape latency of the model group was significantly prolonged, the number of times of crossing the original platform was significantly reduced (P<0.01), the neuronal morphology of hippocampal CA1 area was damaged to varying degrees, the apoptosis rate was significantly increased (P<0.01), the integral optical density and average optical density of PI3K, Akt were significantly reduced (P<0.01), and the integral optical density and average optical density of Caspase-3 were significantly reduced (P<0.01). Compared with model group, the escape latency was shortened (P<0.05, P<0.01), the number of crossing the original platform was increased (P<0.05, P<0.01), the integrated optical density and average optical density of PI3K and Akt were significantly increased (P<0.01), and the integrated optical density and average optical density of Caspase-3 were decreased in different degrees (P<0.05, P<0.01). Conclusion::Modified Dihuang Yinzi can improve the learning and memory ability of vascular dementia model rats and the damaged neurons in the hippocampal CA1 area. The potential mechanism may be related to the activation of PI3K/Akt signal transduction pathway and the inhibition of apoptosis of neurons in hippocampal CA1 area of rats.
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Aim To explore the best method of neural stem cellextraction and culture, and provide a technical reference for thebasic research of neural stem cells. Methods Different extractionand culture methods of neural stem cells were compared.The rate of ball of neural stem cells and the stability of neuralstem cells in undifferentiated state were observed by extraction offetal and neonatal rats cortex, using different types of medium,different inoculation density, different culture methods, differentmethods of changing liquid and different passage methods. Neuralstem cells' activities were detected by Varioskan LUX MultimodeMicroplate Reader. Results ① The brain cortex of fetalrats of 14 d had higher proportion of neural stem cells, less othercells and more neurospheres than newborn rats of 24 h. ② Neuralstem cells could be stabilized in undifferentiated state by usingserum-free medium, while most of the neural stem cellswere differentiated into neurons and glial cells by using serummedium. ③ Neural stem cells, seeding at 1. 0 ×109 ·L-1 , hada large number of neurosperes and were in good condition. ④Suspension culture was beneficial to form a stable neurosphereand keep the neural stem cells in an undifferentiated state thanadherent culture. ⑤ The state of neurosphere by changing halfof the medium and adding medium without discarding was betterthan that by replacing all medium. ⑥ The neurospheres couldbe separated into single cells by mechanical blow in primary generationand the second generation of neurospheres cultured in serum-free medium. While the percentage of viable cells in neuralstem cells was the highest digested with stem cell lysates afterthree generations and the neurospheres re-formed were better. ⑦Neural stem cells' activity of 14 d fetal rat in Accutase digestiongroup was significantly higher than that of the other threegroups, and the difference was significant (P <0. 05). ConclusionsNeural stem cells proliferate and divide well, with highrate of ball formation and good neurosphere condition, which canmaintain a stable undifferentiated state by extracting the cerebralcortex of 14 d fetal rats, using serum-free medium, inoculatinginto a 25 cm2 flask at a density of 1. 0 × 109 ·L-1 , and takingthe suspension culture (adding the medium 1 ~ 1. 5 mL every 2~3 d and passage every 6 ~8 d ).
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Stroke,especially ischemic stroke,is a serious threat to human health due to its high morbidity,le-thality and disability.Cerebral ischemia-reperfusion injury is an important pathophysiological process of ischemic stroke.As an important cell stress protein,DNA damage-inducible transcript 4(DDIT4)protein plays an important role in cerebral is-chemia-reperfusion injury,and it provides a new target for the study and treatment of cerebral ischemia -reperfusion injury. This review will focus on the structure and expression of DDIT 4,and its latest research progress on the regulation of auto-phagy in cerebral ischemia-reperfusion injury.
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The study is to investigate the effect of angiotensin II (Ang II) and its receptor blockers on migration and endothelin-1 (ET-1) expression of rat vascular adventitial fibroblast subpopulations. Vascular adventitial fibroblasts were individually expanded by using cloning rings, and the effects of Ang II on the migration of adventitial fibroblast subpopulations were evaluated by Transwell. Fluorescence quantitative-PCR detected the expression of preproET-1 mRNA induced by Ang II, and its receptor antagonists losartan and PD-123319. The concentration of ET-1 was determined by ELISA. It showed that spindle shaped and epithelioid shaped cells were isolated by using cloning rings, named as spindle cells and round cells. RT-PCR showed that fibroblast subpopulations did not have leukocytes, endothelial cells and smooth muscle cells, namely pure cell lines. Compared with respective control cells, two subpopulations had transferring ability. Ang II significantly improved round cells migration in a concentration-dependent manner, and had no obvious influence on spindle cells migration. Ang II (1 x 10(-8) - 1 x 10(-6) mol x L(-1)) significantly increased the expression of preproET-1 mRNA in round cells (P < 0.01), and had no significant effect on the expression of preproET-1 mRNA in spindle cells. Losartan blocked the expression of preproET-1 mRNA induced by Ang II in round cells, and had no significant effect on the expression of preproET-1 mRNA in spindle cells. The effects of Ang II and ET-1 receptor inhibitors on the release of ET-1 were similar to the expression of preproET-1 mRNA. The results indicate that there are two cell subpopulations: round cells and spindle cells in rat vascular adventitial fibroblasts. Ang II significantly improved cells migration, and increased the expression of ET-1 in round cell subpopulation. It suggested that there may be different migratory mechanisms in two cell subpopulations, and the two subpopulations may play a different role in vascular remodeling and reparative process.