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Oxidative disruption of dopaminergic neurons is regarded as a crucial pathogenesis in Parkinson's disease (PD), eventually causing neurodegenerative progression. (-)-Clausenamide (Clau) is an alkaloid isolated from plant Clausena lansium (Lour.), which is well-known as a scavenger of lipid peroxide products and exhibiting neuroprotective activities both in vivo and in vitro, yet with the in-depth molecular mechanism unrevealed. In this study, we evaluated the protective effects and mechanisms of Clau on dopaminergic neuron. Our results showed that Clau directly interacted with the Ser663 of ALOX5, the PKCα-phosphorylation site, and thus prevented the nuclear translocation of ALOX5, which was essential for catalyzing the production of toxic lipids 5-HETE. LC-MS/MS-based phospholipidomics analysis demonstrated that the oxidized membrane lipids were involved in triggering ferroptotic death in dopaminergic neurons. Furthermore, the inhibition of ALOX5 was found to significantly improving behavioral defects in PD mouse model, which was confirmed associated with the effects of attenuating the accumulation of lipid peroxides and neuronal damages. Collectively, our findings provide an attractive strategy for PD therapy by targeting ALOX5 and preventing ferroptosis in dopaminergic neurons.
Assuntos
Ferroptose , Doença de Parkinson , Animais , Camundongos , Neurônios Dopaminérgicos , Cromatografia Líquida , Espectrometria de Massas em TandemRESUMO
Coicis Semen is widely used as a raw material which can be used as both medicine and food among people. According to the ancient monographs on materia medica and relevant documents on the processing specifications in various provinces and cities, herba logical study on the historical evolution of the processing methods of Coicis Semen was conducted in this paper from the aspects of collecting and processing methods of Coicis Semen, the processing methods in the past dynasties and the nature, flavour and efficacy of Coicis Semen. The results showed that the processing methods of Coicis Semen recorded in monographs on materia medica mainly included stir-frying, glutinous rice stir-frying, salt processing(including salt cooking and salt stir-frying), stir-frying with the earth scraped from the wall facing east, and ginger juice stir-frying, etc. Among them, stir-frying, and stir-frying with the earth scraped from the wall facing east are still used nowadays. The bran stir-frying is the improved version of glutinous rice stir-frying in order to be adaptive to the modern-day situation and the needs of the present. In addition, the ancient shell removal and kernel keeping method are also included in the processing procedures in modern local processing specifications, which are combined with frying to form a new method named "Fazhi" processing( "Fazhi" means a processing method of multiple procedures). The 2015 edition of Chinese Pharmacopoeia records that Coicis Semen is helpful to clear dampness and promote diuresis, strengthen the spleen and prevent diarrhea, eliminate impediment, discharge pus, resolve toxin and a mass, etc., which are consistent with those contained in ancient monographs on materia medica. After the "Fazhi" processing, the cold nature of Coicis Semen has been removed and its nature,flavour and meridian tropism have been changed, so its application scopes expanded. The results of this study clearly traced the history of the collecting and proces-sing of Coicis Semen, summarized the nature, flavour and efficacy of Coicis Semen contained in both ancient and modern literature, and provided a historical basis for the standardization of the subsequent processing technology of Coicis Semen, the clinical application of various processed products, and the further development and utilization of medicinal materials.
Assuntos
Coix , Medicamentos de Ervas Chinesas , Materia Medica , Oryza , Zingiber officinale , Culinária , Medicina Tradicional ChinesaRESUMO
Citri Sarcodactylis Fructus is a both medicinal and edible species specified by the China Ministry of Health, with a long history in China. According to the ancient monographs about materia medica, it was found that the records of the Citri Sarcodactylis Fructus on the original plants were confused. This paper reviewed the ancient monographs about materia medica, and made a summarization and textual research on the name, origin, habitat, processing methods, medicinal properties and clinicacy efficacy of Citri Sarcodactylis Fructus based the comprehensive analysis on modern literatures and authoritative books of Chinese herbal medicine. The results indicated that there were many bynames of Citri Sarcodactylis Fructus. Before the Yuan Dynasty, there was a mixed use of Citri Sarcodactylis Fructus and Citri Fructus, which were not distinguished from each other in terms of nature and taste until the Yuan dynasty. Citri Sarcodactylis Fructus was a varietas of Citri Fructus. The main shape of the original plant of Citri Sarcodactylis Fructus is "like a human hand with fingers" as recorded in ancient monographs about materia medica. The main places of origin of Citri Sarcodactylis Fructus were Guangdong, Zhejiang, Fujian, Sichuan, which were relatively stable. There were fewer records about medicinal proces-sing methods of Citri Sarcodactylis Fructus. Only steaming and baking methods were found in ancient monographs about materia medica, and the steaming method could reduce the irritability of Citri Sarcodactylis Fructus. The processing of therapeutic dietary of Citri Sarcodactylis Fructus was widely used in folk, which was represented by Chaozhou Laoxianghuang, a traditional succade made of Citri Sarcodactylis Fructus. According to the 2015 edition of Chinese Pharmacopoeia, Citri Sarcodactylis Fructus had effects in soothing liver and regulating gas, relieving pain in the stomach, eliminating dampness and resolving phlegm, which was basically consistent with the descriptions in ancient monographs about materia medica. This paper defined the original plant of Citri Sarcodactylis Fructus, and sorted out and summarized the processing methods, nature and taste of Citri Sarcodactylis Fructus, so as to provide data support for the standardization of the processing technology and the development and utilization of Citri Sarcodactylis Fructus.
Assuntos
Medicamentos de Ervas Chinesas , Materia Medica , China , Frutas , Humanos , Medicina Tradicional ChinesaRESUMO
Honeycomb structure endows graphene with extraordinary properties. But could a honeycomb monolayer superlattice also be generated via self-assembly of colloids or nanoparticles? Here we report the construction of mono- and multilayer molecular films with honeycomb structure that can be regarded as self-assembled artificial graphene (SAAG). We construct fan-shaped molecular building blocks by covalently connecting two kinds of clusters, one polyoxometalate and four polyhedral oligomeric silsesquioxanes. The precise shape control enables these complex molecules to self-assemble into a monolayer 2D honeycomb superlattice that mirrors that of graphene but on the mesoscale. The self-assembly of the SAAG was also reproduced via coarse-grained molecular simulations of a fan-shaped building block. It revealed a hierarchical process and the key role of intermediate states in determining the honeycomb structure. Experimental images also show a diversity of bi- and trilayer stacking modes. The successful creation of SAAG and its stacks opens up prospects for the preparation of novel self-assembled nanomaterials with unique properties.
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Clusters with diverse structures and functions have been used to create novel cluster-assembled materials (CAMs). Understanding their self-assembly process is a prerequisite to optimize their structure and function. Herein, two kinds of unlike organo-functionalized inorganic clusters are covalently linked by a short organic tether to form a dumbbell-shaped Janus co-cluster. In a mixed solvent of acetonitrile and water, it self-assembles into a crystal with a honeycomb superstructure constructed by hexagonal close-packed cylinders of the smaller cluster and an orderly arranged framework of the larger cluster. Reconstruction of these structural features via coarse-grained molecular simulations demonstrates that the cluster crystallization and the nanoscale phase separation between the two incompatible clusters synergistically result in the unique nano-architecture. Overall, this work opens up new opportunities for generating novel CAMs for advanced future applications.
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The lateral parabrachial nucleus (LPBN) is known to play a key role in relaying noxious information from the spinal cord to the brain. Different LPBN efferent mediate different aspects of the nocifensive response. However, the function of the LPBN â lateral hypothalamus (LH) circuit in response to noxious stimuli has remained unknown. Here, we show that LPBN â LH circuit is activated by noxious stimuli. Interestingly, either activation or inhibition of this circuit induced analgesia. Optogenetic activation of LPBN afferents in the LH elicited spontaneous jumping and induced place aversion. Optogenetic inhibition inhibited jumping behavior to noxious heat. Ablation of LH glutamatergic neurons could abolish light-evoked analgesia and jumping behavior. Our study revealed a role for the LPBN â LH pathway in nocifensive behaviors.
Assuntos
Região Hipotalâmica Lateral , Núcleos Parabraquiais , Humanos , Núcleos Parabraquiais/fisiologia , Dor/metabolismo , Encéfalo , Neurônios/metabolismoRESUMO
Parkinson's disease (PD) is a neurodegenerative disorder associated with α-synuclein aggregation and dopaminergic neuron loss in the midbrain. There is evidence that psychological stress promotes PD progression by enhancing glucocorticoids-related oxidative damage, however, the mechanisms involved are unknown. The present study demonstrated that plasma membrane phospholipid peroxides, as determined by phospholipidomics, triggered ferroptosis in dopaminergic neurons, which in turn contributed to stress exacerbated PD-like motor disorder in mice overexpressing mutant human α-synuclein. Using hormonomics, we identified that stress stimulated corticosteroid release and promoted 15-lipoxygenase-1 (ALOX15)-mediated phospholipid peroxidation. ALOX15 was upregulated by α-synuclein overexpression and acted as a fundamental risk factor in the development of chronic stress-induced parkinsonism and neurodegeneration. Further, we demonstrated the mechanism by which corticosteroids activated the PKC pathway and induced phosphatidylethanolamine-binding protein-1 (PEBP1) to form a complex with ALOX15, thereby facilitating ALOX15 to locate on the plasma membrane phospholipids. A natural product isolated from herbs, leonurine, was screened with activities of inhibiting the ALOX15/PEBP1 interaction and thereby attenuating membrane phospholipid peroxidation. Collectively, our findings demonstrate that stress increases the susceptibility of PD by driving membrane lipid peroxidation of dopaminergic neurons and suggest the ALOX15/PEBP1 complex as a potential intervention target.
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Doença de Parkinson , Camundongos , Humanos , Animais , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Neurônios Dopaminérgicos/metabolismo , Suscetibilidade a Doenças/metabolismo , Estresse PsicológicoRESUMO
Background: Adult neurogenesis plays an important role in repairing damaged neurons and improving cognitive impairment in Alzheimer's disease (AD). B. Papyrifera (L.) L'Hér. ex Vent. fruits (BL), a traditional Chinese medicine for tonifying the kidney, has been reported to improve cognitive function in AD mice, but the underlying mechanisms have not been clearly illuminated. This study aimed to provide an overview of the differential compounds in the brain of APP/PS1 mice after BL water extract (BLWE) treatment through metabolomics technology and to elucidate whether the therapeutic effect and mechanism are through the enhancement of neurogenesis. Methods: APP/PS1 transgenic mice were treated with different doses of BLWE. After 6 weeks of intragastric injection, the therapeutic effects of BLWE on APP/PS1 transgenic mice were determined by the Morris water maze test, immunohistochemistry, hematoxylin & eosin and Nissl staining, enzyme-linked immunosorbent assay and terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Subsequently, metabolomics technology was used to analyze the regulatory effect of BLWE on differential compounds in the brain of APP/PS1 mice, and on this basis, its molecular mechanism of BLWE was screened. Finally, the protein expression of the Wnt/ß-catenin signaling pathway was detected by Western blotting. Results: After BLWE treatment, the learning and memory function of APP/PS1 mice were significantly improved, which was related to the increase in the number of Nestin+/BrdU+ and NeuN+/BrdU+ cells, and the decrease in the number of apoptotic cells in the hippocampus. BLWE treatment could also up-regulate the expression of synapse-associated proteins. Moreover, BLWE could modulate endogenous metabolic compounds in the brains of AD mice, including N-acetyl-aspartate, glutamine, etc. Furthermore, BLWE inhibited the phosphorylation of Tyr216-GSK-3ß and ß-catenin protein while increased CyclinD1 protein expression. Conclusion: We demonstrated that BLWE can enhance neural stem cells proliferation and improve neurogenesis, thereby efficiently repairing damaged neurons in the hippocampus and ameliorating cognitive impairment in APP/PS1 transgenic mice. The mechanism is at least partly through activating the Wnt/ß-catenin signaling pathway.
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A highly active secretory expression system in Bacillus subtilis was constructed for enhancing the heterogeneous secretory expression efficiency of a recombinant amidase from Bacillus megaterium (Bm-Ami). Initially, six promoters PlytR, PspoVG, PaprE, PyvyD, PftsH, PamyE were screened out from 33 endogenous phase-dependent promoters via the strategy of promoter engineering which showed higher transcriptional levels than the original promoter Pcdd. Afterwards, a secretory expression system pBSHdd2-20 containing a dual-promoter PamyE-cdd and a signal peptide Pac was constructed showing an extracellular Bm-Ami activity of 135.58 U mL-1 during shake-flask cultivation, which was 3.58-fold greater than that with plasmid pBSH1 (control). Finally, extracellular amidase activity of a strain containing the plasmid pBSHdd2-20 reached 430 U mL-1 (equal to 10.8 mg mL-1) and 10.72 U mg-1DCW after 52 h in a scale-up fermentation, which was the highest secretory efficiency for Bm-Ami in all studies to date. In conclusion, a highly secretory system constructed in this study can be applied for the industrial production of amidase and provides a basis for the development of an excellent secretory expression system for similar proteins.