RESUMO
Eight hybrids of amantadine (ATD) with a natural modulator gardenamide A (GA) via an alkylene carbonyl bridge or alkylene bridge have been designed and synthesized. Evaluated by electrophysiological assay, compound 5b was confirmed an enhanced NMDAR antagonist compared to ATD with IC50 value of 10.2 ± 1.2 µM. 5b has been demonstrated to reverse the damages of behavioral performance, the loss of dopaminergic neurons, the reduction of TH positive, and the increase of α-synuclein in both MPTP-treated mice and zebrafish models. In both ethological and ecological experiments, the activity of 5b was confirmed better than ATD or ATD/GA combination, and was almost equal to the positive selegiline. In vivo and in vitro, 5b is shown to reverse the ascend of NR1 and i-NOS levels. This candidate was also demonstrated the activity to down-regulated MPTP-increased Ca2+ influx in SH-SY5Y cells in a steep and sharp mode. It is displayed that 5b exerts neuroprotective effect partly by activating the PI3K/Akt signaling pathway. Taken all together, our data support that 5b is a more promising agent against PD than ATD.
Assuntos
N-Metilaspartato , Neuroblastoma , Humanos , Camundongos , Animais , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Fosfatidilinositol 3-Quinases/metabolismo , Peixe-Zebra/metabolismo , Camundongos Endogâmicos C57BL , Amantadina/farmacologiaRESUMO
The damage of vascular endothelial cells induced by oxidative stress plays an important role in the pathogenesis of atherosclerosis. Dihydromyricetin (DMY) is considered as a natural antioxidant. However, the mechanism of DMY on endothelial cell injury induced by oxidative stress remains unclear. In this study, we found that DMY could reduce the oxidative damage of HUVECs induced by sodium nitroprusside (SNP), HUVECs pre-treated with DMY suppressed SNP-induced apoptosis by reduced ROS overproduction of intracellular, decreased MDA level and elevated the superoxide dismutase activity. Meanwhile, we found that DMY could promote the expression of phosphorylated FoxO3a and Akt, and affect the nuclear localization of FoxO3a, when treated with the PI3K inhibitor LY294002, the effect of DMY was blocked. These data suggest that DMY protects HUVECs from oxidative stress by activating PI3K/Akt/FoxO3a signalling pathway. Therefore, DMY may have great therapeutic potential as a new drug for atherosclerosis.
Assuntos
Citoproteção/efeitos dos fármacos , Flavonóis/farmacologia , Proteína Forkhead Box O3/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Nitroprussiato/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Morte Celular/efeitos dos fármacos , Cromonas/farmacologia , Flavonóis/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Modelos Biológicos , Morfolinas/farmacologia , Fosforilação/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
CHR20 and CHR21 are a pair of stable diastereoisomers derived from genipin. These stereoisomers are activators of neuronal nitric oxide synthase (nNOS) and endothelial nitric oxide synthase (eNOS). In the rat retinal ganglion (RGC-5) cell model these compounds are non-toxic. Treatment of RGC-5 with 750 µM of sodium nitroprusside (SNP) produces nitrosative stress. Both genipin derivatives, however, protect these cells against SNP-induced apoptic cell death, although CHR21 is significantly more potent than CHR20 in this regard. With Western blotting we showed that the observed neuroprotection is primarily due to the activation of protein kinase B (Akt)/eNOS and extracellular signal-regulated kinase (ERK1/2) signaling pathways. Therefore, LY294002 (a phosphatidylinositol 3-kinase (PI3K) inhibitor) or PD98059 (a MAPK-activating enzyme inhibitor) abrogated the protective effects of CHR20 and CHR21. Altogether, our results show that in our experimental setup neuroprotection by the diasteromeric pair is mediated through the PI3K/Akt/eNOS and ERK1/2 signaling pathways. Further studies are needed to establish the potential of these compounds to prevent ntric oxide (NO)-induced toxicity commonly seen in many neurodegenerative diseases.
Assuntos
Iridoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Nitroprussiato/farmacologia , Células Ganglionares da Retina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromonas/farmacologia , Flavonoides/farmacologia , Regulação da Expressão Gênica , Iridoides/síntese química , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Morfolinas/farmacologia , Fármacos Neuroprotetores/síntese química , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/química , Óxido Nítrico/farmacologia , Doadores de Óxido Nítrico/antagonistas & inibidores , Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/farmacologia , Estresse Oxidativo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/metabolismoRESUMO
Gardenamide A (GA) protects the rat retinal ganglion (RGC-5) cells against cell apoptosis induced by H2O2. The protective effect of GA was completely abrogated by the specific phosphoinositide 3-kinase (PI3K) inhibitor LY294002, and the specific protein kinase B (Akt) inhibitor Akt VIII respectively, indicating that the protective mechanism of GA is mediated by the PI3K/Akt signaling pathway. The specific extracellular signal-regulated kinase (ERK1/2) inhibitor PD98059 could not block the neuroprotection of GA. GA attenuated the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) induced by H2O2. Western blotting showed that GA promoted the phosphorylation of ERK1/2, Akt and endothelial nitric oxide synthase (eNOS), respectively, and effectively reversed the H2O2-inhibited phosphorylation of these three proteins. LY294002 completely inhibited the GA-activated phosphorylation of Akt, while only partially inhibiting eNOS. This evidence implies that eNOS may be activated directly by GA. PD98059 attenuated only partially the GA-induced phosphorylation of ERK1/2 with/without the presence of H2O2, indicating that GA may activate ERK1/2 directly. All these results put together confirm that GA protects RGC-5 cells from H2O2 insults via the activation of PI3K/Akt/eNOS signaling pathway. Whether the ERK1/2 signaling pathway is involved requires further investigations.
Assuntos
Antioxidantes/farmacologia , Iridoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo , Células Ganglionares da Retina/efeitos dos fármacos , Sistemas do Segundo Mensageiro , Animais , Linhagem Celular , Peróxido de Hidrogênio/toxicidade , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Células Ganglionares da Retina/metabolismoRESUMO
Two amantadine (ATD)-gardenamide A (GA) ligands have been designed and synthesized. The bonding of ATD with GA through a methylene carbonyl brigde (L1) enhances the neuroprotective effect against corticosterone (CORT)-induced impairments in PC12 cells; while the bonding through a succinyl brigde (L2) does not. L1 reduces the level of reactive oxygen species (ROS) and cell apoptosis generated by CORT. It restores CORT-changed cell morphology to a state that is closed to normal PC12 cells. One mechanism of L1 to attenuate CORT-induced cell apoptosis is through the adjustment of both caspase-3 and Bcl-2 proteins. Like GA, both nNOS and eNOS might be involved in the neuroprotective mechanism of L1. All the evidences suggest that L1 may be a potential agent to treat depression.
Assuntos
Amantadina/análogos & derivados , Amantadina/farmacologia , Apoptose/efeitos dos fármacos , Iridoides/química , Iridoides/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Animais , Corticosterona/efeitos adversos , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND AND OBJECTIVE: The effective segmentation of esophageal squamous carcinoma lesions in CT scans is significant for auxiliary diagnosis and treatment. However, accurate lesion segmentation is still a challenging task due to the irregular form of the esophagus and small size, the inconsistency of spatio-temporal structure, and low contrast of esophagus and its peripheral tissues in medical images. The objective of this study is to improve the segmentation effect of esophageal squamous cell carcinoma lesions. METHODS: It is critical for a segmentation network to effectively extract 3D discriminative features to distinguish esophageal cancers from some visually closed adjacent esophageal tissues and organs. In this work, an efficient HRU-Net architecture (High-Resolution U-Net) was exploited for esophageal cancer and esophageal carcinoma segmentation in CT slices. Based on the idea of localization first and segmentation later, the HRU-Net locates the esophageal region before segmentation. In addition, an Resolution Fusion Module (RFM) was designed to integrate the information of adjacent resolution feature maps to obtain strong semantic information, as well as preserve the high-resolution features. RESULTS: Compared with the other five typical methods, the devised HRU-Net is capable of generating superior segmentation results. CONCLUSIONS: Our proposed HRU-NET improves the accuracy of segmentation for squamous esophageal cancer. Compared to other models, our model performs the best. The designed method may improve the efficiency of clinical diagnosis of esophageal squamous cell carcinoma lesions.
Assuntos
Neoplasias Esofágicas , Redes Neurais de Computação , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/radioterapia , Tomografia Computadorizada por Raios X/métodos , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Carcinoma de Células Escamosas do Esôfago/radioterapia , Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodosRESUMO
Effectively reducing the inflammatory response after spinal cord injury (SCI) is a challenging clinical problem and the subject of active investigation. This study employed a porous scaffold-based three dimensional long-term culture technique to obtain human umbilical cord mesenchymal stem cell (hUC-MSC)-derived Small Extracellular Vesicles (sEVs) (three dimensional culture over time, the "4D-sEVs"). Moreover, the vesicle size, number, and inner protein concentrations of the MSC 4D-sEVs contained altered protein profiles compared with those derived from 2D culture conditions. A proteomics analysis suggested broad changes, especially significant upregulation of Epidermal Growth Factors Receptor (EGFR) and Insulin-like Growth Factor Binding Protein 2 (IGFBP2) in 4D-sEVs compared with 2D-sEVs. The endocytosis of 4D-sEVs allowed for the binding of EGFR and IGFBP2, leading to downstream STAT3 phosphorylation and IL-10 secretion and effective induction of macrophages/microglia polarization from the pro-inflammatory M1 to anti-inflammatory M2 phenotype, both in vitro and in the injured areas of rats with compressive/contusive SCI. The reduction in neuroinflammation after 4D-sEVs delivery to the injury site epicenter led to significant neuroprotection, as evidenced by the number of surviving spinal neurons. Therefore, applying this novel 4D culture-derived Small Extracellular Vesicles could effectively curb the inflammatory response and increase tissue repair after SCI.
RESUMO
We previously constructed a three-dimensional gelatin sponge (3D-GS) scaffold as a delivery vehicle for therapeutic cells and trophic factors in the treatment of spinal cord injury (SCI), and this study aimed to assess the biosafety and efficacy of the scaffold in a non-human primate SCI model. However, because it has only been tested in rodent and canine models, the biosafety and efficacy of the scaffold should ideally be assessed in a non-human primate SCI model before its use in the clinic. No adverse reactions were observed over 8 weeks following 3D-GS scaffold implantation into in a Macaca fascicularis with hemisected SCI. Scaffold implantation also did not add to neuroinflammatory or astroglial responses already present at the injured site, suggesting good biocompatibility. Notably, there was a significant reduction in α-smooth muscle actin (αSMA)-positive cells at the injury/implantation interface, leading to alleviation of fibrotic compression of the residual spinal cord tissue. The regenerating tissue in the scaffold showed numerous cells migrating into the implant secreting abundant extracellular matrix, resulting in a pro-regenerative microenvironment. Consequently, nerve fiber regeneration, myelination, vascularization, neurogenesis, and electrophysiological improvements were achieved. These results indicated that the 3D-GS scaffold had good histocompatibility and effectiveness in the structural repair of injured spinal cord tissue in a non-human primate and is suitable for use in the treatment of patients with SCI.
Assuntos
Gelatina , Traumatismos da Medula Espinal , Animais , Cães , Gelatina/química , Alicerces Teciduais/química , Traumatismos da Medula Espinal/terapia , Regeneração Nervosa/fisiologia , Medula Espinal , PrimatasRESUMO
(Purpose/Significance). This paper aims at the problems of inaccurate recommendation effect caused by data sparseness and cold start in the traditional collaborative filtering-based book personalized recommendation algorithm. So this paper proposes a collaborative filtering recommendation algorithm which improves the similarity solution method and the filling method of missing data. (Method/Process). By considering the influence of the user's common rating book collection on the similarity calculation, the average rating value of all books is used as the threshold, and the user's common rating weight is introduced into the user's similarity calculation. As for data filling, according to the user's average rating, the basic attributes such as the age and gender of users are coded, and then Euclidean distance is initially calculated, making hierarchical clustering on users. What's more, Shope-one algorithm is used to calculate the filling value of the former m similar usersï¼and add the weight value of the degree simultaneously to get the final filling value, so as to improve the data filling method. (Result/Conclusion). Experiments were carried out with the data set of Book-Crossing Data set through Python. The experimental results show that the improved collaborative filtering algorithm has a significantly improvement in the accuracy and quality of book recommendation.
Assuntos
Algoritmos , Livros , Análise por ConglomeradosRESUMO
With the gradual expansion of the book logistics market and the year-on-year increase in book publications, the incidence of book reverse logistics continues to increase, and the problem of book companies' inventory backlog has become increasingly prominent. To effectively alleviate the current backlog of book returns and exchanges, this paper constructs a two-party game model of "book publisher-book retailer," analyzes the evolution process of book publishers and book retailers' participation strategies and the influence of parameter changes on stable strategies through theoretical analysis and numerical simulation, and draws the following conclusions. (1) Whether book publishers and book retailers choose to participate in the reverse logistics optimization of book returns and exchanges is closely related to their benefits and costs, and it also depends on whether the other party participates in the reverse logistics optimization of books. (2) When the cost of participating in book reverse logistics reaches a certain condition, the probability of both parties participating in the optimization is the greatest.
Assuntos
Livros , Opinião Pública , Simulação por ComputadorRESUMO
Background: Previous studies have shown that electroacupuncture (EA) has a positive effect on motor and sensory function in patients with spinal cord injury (SCI). This review evaluated the effectiveness of EA for improvement in activities of daily living in patients with SCI. Methods: We searched the Cochrane Library, PubMed, Web of Science, CNKI, WanFang Data, and VIP databases using a search strategy according to the guidelines of the Cochrane Handbook for Systematic Review of Interventions up to 30th September 2020. Only randomized controlled trials (RCTs) of EA in patients with SCI were included. We analyzed the data using RevMan (version 5.3) and graded the quality of evidence using GRADE profiler 3.6.1. Results: This meta-analysis included 10 RCTs with 712 patients. Three studies revealed that the functional independence measure score for SCI patients in the EA group was higher than that in the control group (mean difference [MD] = 13.46, 95% CI: 8.00 to 18.92, P < 0.00001). Five studies showed that the modified Barthel index in the EA group was higher than that in the control group (MD = 6.92, 95% CI: 4.96 to 8.89, P < 0.00001). Five studies showed that the American Spinal Injury Association-motor score (ASIA-motor score) in the EA group was higher than that in the control group (standard MD = 0.96, 95% CI: 0.75 to 1.18, P < 0.00001). Three studies reported the ASIA-tactile and pain scores and also reported that the scores in the EA group were higher than those in the control group, with high homogeneity (tactile I2 = 86%, P = 0.0008; pain I2 = 54%, P = 0.11). The quality of evidence for the use of EA for improvement in motor and sensory function in SCIs was moderate according to the GRADE system. Conclusion: This review suggested that EA improves activities of daily living and motor function in patients with SCI, with a moderate level of evidence.