RESUMO
Oxidative stress and blood-brain barrier (BBB) disruption play important roles in cerebral ischemic pathogenesis and may represent targets for treatment. Earlier studies have shown that osthole, a main active constituent isolated from Cnidium monnieri (L.) Cusson, could be considered as an attractive therapeutic agent in the treatment of ischemic stroke. However, the mechanism underlying the protective effect remains vague. In this study we aimed to investigate the effect of osthole on transient cerebral ischemia as well as its mechanism(s) in C57 BL/6 J mice. Mice were subjected to transient global cerebral ischemia induced by bilateral common carotid artery occlusion for 25 min. Behavioral test was performed at 4 days after ischemia, followed by assessment of neuronal loss in hippocampal CA1 region. Osthole significantly improved the cognitive ability and enhanced the survival of pyramidal neurons in the CA1 region of mice after lesion. Further studies showed that osthole attenuated the permeation of BBB, which may contribute to antioxidative effect by increasing the superoxide dismutase activity and decreasing the malondialdehyde level in model mice. Further studies revealed that osthole obviously up-regulated the protein levels of nuclear factor erythroid 2-related factor 2/heme oxygenase 1 in HT22 cells. In conclusion, our findings indicated that osthole exerts neuroprotective effects against global cerebral ischemia injury by reducing oxidative stress injury and reserving the disruption of BBB, which may be attributed to elevating the protein levels of Nrf2 and HO-1.
Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Cumarínicos/farmacologia , Ataque Isquêmico Transitório/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Nootrópicos/farmacologia , Animais , Células Cultivadas , Heme Oxigenase-1/metabolismo , Hipocampo/patologia , Ataque Isquêmico Transitório/patologia , Ataque Isquêmico Transitório/psicologia , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Superóxido Dismutase/metabolismoRESUMO
Early diagnosis of acute ST-segment elevation myocardial infarction (STEMI) and early determination of the culprit vessel are associated with a better clinical outcome. We developed three deep learning (DL) models for detecting STEMIs and culprit vessels based on 12-lead electrocardiography (ECG) and compared them with conclusions of experienced doctors, including cardiologists, emergency physicians, and internists. After screening the coronary angiography (CAG) results, 883 cases (506 control and 377 STEMI) from internal and external datasets were enrolled for testing DL models. Convolutional neural network-long short-term memory (CNN-LSTM) (AUC: 0.99) performed better than CNN, LSTM, and doctors in detecting STEMI. Deep learning models (AUC: 0.96) performed similarly to experienced cardiologists and emergency physicians in discriminating the left anterior descending (LAD) artery. Regarding distinguishing RCA from LCX, DL models were comparable to doctors (AUC: 0.81). In summary, we developed ECG-based DL diagnosis systems to detect STEMI and predict culprit vessel occlusion, thus enhancing the accuracy and effectiveness of STEMI diagnosis.
RESUMO
OBJECTIVES: This review summarizes recent research on the neuropharmacological and pharmacokinetic properties of berberine, an isoquinoline alkaloid extracted from Coptidis rhizoma. KEY FINDINGS: Berberine has multiple neuropharmacological properties, such as neuroprection, anti-neuronal apoptosis, improvement of cerebral microcirculation and anti-Alzheimer's disease, and so on. The pharmacokinetic characteristics of berberine are that it is not easily absorbed and it is not stable in the gastrointestinal tract of animals or humans. SUMMARY: Further studies need to be carried out to develop berberine as a drug for nervous system diseases, such as brain ischaemia and Alzheimer's disease, that has favorable pharmacokinetic properties.
Assuntos
Berberina , Fármacos Neuroprotetores , Doença de Alzheimer/tratamento farmacológico , Animais , Berberina/farmacocinética , Berberina/farmacologia , Berberina/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/fisiopatologia , Humanos , Fármacos Neuroprotetores/farmacocinética , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêuticoRESUMO
Oxidative stress is closely related to the pathogenesis of neurodegenerative disorders such as Parkinson's disease (PD). In this study, we investigated the neuroprotective effect of tacrine-ferulic acid dimers linked by an alkylenediamine side chain (TnFA, n=2-7), a series of novel acetylcholinesterase inhibitors, against 6-hydroxydopamine (6-OHDA)-induced apoptosis in PC12 cells. Among these dimers, pre-treatment of tacrine(2)-ferulic acid (T2FA, 3-30 µM) attenuated 6-OHDA-induced apoptosis in a concentration-dependent manner. The activations of glycogen synthase kinase 3ß (GSK3ß) and extracellular signal-regulated kinase (ERK) were observed after the treatment of 6-OHDA. Both SB415286 (an inhibitor of GSK3ß) and PD98059 (an inhibitor of ERK kinase) reduced the neurotoxicity induced by 6-OHDA, indicating that GSK3ß and ERK are involved in 6-OHDA-induced apoptosis. T2FA was able to inhibit the activation of GSK3ß, but not ERK, in an Akt-dependent manner. Furthermore, LY294002, a phosphoinositide 3-kinase inhibitor, abolished the neuroprotective effect of T2FA. Collectively, these results suggest that T2FA prevents 6-OHDA-induced apoptosis possibly by activating the Akt pathway in PC12 cells.
Assuntos
Apoptose/efeitos dos fármacos , Ácidos Cumáricos/farmacologia , Oxidopamina/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tacrina/farmacologia , Animais , Ácidos Cumáricos/química , Dimerização , Ativação Enzimática , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo , Tacrina/químicaRESUMO
Previously we demonstrated that Osthole, a natural coumarin, protects against focal cerebral ischemia/reperfusion-induced injury in rats. In the present study, the effects of Osthole on neurobehavioral functions, infarct volume and matrix metalloproteinase-9 (MMP-9) in a rat 2h focal cerebral ischemia model were investigated. Osthole (100mg/kg per dose) was administrated intraperitoneally 30min before ischemic insult and immediately after reperfusion. Osthole treatment significantly reduced neurological deficit score and infarct volume by 38.5% and 33.8%, respectively, as compared with the untreated animals. Osthole reversed ischemia-reperfusion-induced increase in MMP-9 protein level/activity as evidenced by Western blotting and gelatin zymography. Taken together, these results for the first time demonstrate that Osthole reduces infarct volume, restores neurobehavioral functions and downregulates MMP-9 protein level/activity in ischemia/reperfused brain.