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1.
Pharmacol Res ; 201: 107098, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325728

RESUMO

Neuronal death is one of the key pathologies in Alzheimer's disease (AD). How neuronal death begins in AD is far from clear, so clarifying this process may help develop effective therapies. This study collected single-cell RNA sequencing data of 85 AD samples and 83 control samples, covering the prefrontal cortex, internal olfactory cortex, superior parietal lobe, superior frontal gyrus, caudal internal olfactory cortex, somatosensory cortex, hippocampus, superior frontal cortex and peripheral blood mononuclear cells. Additionally, spatial transcriptomic data of coronal sections from 6 AppNL-G-F AD mice and 6 control C57Bl/6 J mice were acquired. The main single-cell and spatial transcriptomics results were experimentally validated in wild type and 5 × FAD mice. We found that the microglia subpopulation Mic_PTPRG can communicate with specific types of neurons (especially excitatory ExNeu_PRKN_VIRMA and inhibitory InNeu_PRKN_VIRMA neuronal subpopulations) and cause them to express PTPRG during AD progression. Within neurons, PTPRG binds and upregulates the m6A methyltransferase VIRMA, thus inhibiting translation of PRKN mRNA to prevent the clearance of damaged mitochondria in neurons through suppressing mitophagy. As the disease progresses, the energy and nutrient metabolic pathways in neurons are reprogrammed, leading to their death. Consistently, we determined that PTPTRG can physically interact with VIRMA in mouse brains and PRKN is significantly upregulated in 5 × FAD mouse brain. Altogether, our findings demonstrate that PTPRG activates the m6A methyltransferase VIRMA to block mitophagy-mediated neuronal death in AD, which is a potential pathway, through which microglia and neuronal PTPRG modify neuronal connections in the brain during AD progression.


Assuntos
Doença de Alzheimer , Animais , Camundongos , Doença de Alzheimer/genética , Leucócitos Mononucleares , Mitofagia , Perfilação da Expressão Gênica , Metiltransferases , Camundongos Endogâmicos C57BL
2.
BMC Plant Biol ; 23(1): 20, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627574

RESUMO

Although the interaction between P and Zn has long been recognized in plants, the physiological and molecular mechanisms underlying P and Zn interactions are poorly understood. We show here that P supply decreases the Zn concentration in maize shoots and roots. Compared to +P + Zn (addition of both P and Zn), +P-Zn reduced and -P-Zn increased the total length of 1° lateral roots (LRs). Under +P + Zn, both P and Zn concentrations were lower in the sl1 mutant roots than in wild-type (WT) maize roots, and P accumulation did not reduce the Zn concentration in ll1 mutant roots. Transcriptome profiling showed that the auxin signaling pathway contributed to P-mediated Zn homeostasis in maize. Auxin production and distribution were altered by changes in P and Zn supply. Cytosolic Zn co-localized with auxin accumulation under +P + Zn. Exogenous application of 1-NAA and L-Kyn altered the P-mediated root system architecture (RSA) under Zn deficiency. -P-Zn repressed the expression of miR167. Overexpression of ZmMIR167b increased the lengths of 1° LRs and the concentrations of P and Zn in maize. These results indicate that auxin-dependent RSA is important for P-mediated Zn homeostasis in maize.HighlightAuxin-dependent RSA is important for P-mediated Zn homeostasis in maize.


Assuntos
Fósforo , Zea mays , Fósforo/metabolismo , Zea mays/metabolismo , Raízes de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Homeostase , Zinco/metabolismo , Transdução de Sinais
3.
BMC Cancer ; 23(1): 550, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322413

RESUMO

BACKGROUND: As an adult tumor with the most invasion and the highest mortality rate, the inherent heterogeneity of glioblastoma (GBM) is the main factor that causes treatment failure. Therefore, it is important to have a deeper understanding of the pathology of GBM. Some studies have shown that Eukaryotic Initiation Factor 4A-3 (EIF4A3) can promote the growth of many people's tumors, and the role of specific molecules in GBM remains unclear. METHODS: The correlation between the expression of EIF4A3 gene and its prognosis was studied in 94 GBM patients using survival analysis. Further in vitro and in vivo experiments, the effect of EIF4A3 on GBM cells proliferation, migration, and the mechanism of EIF4A3 on GBM was explored. In addition, combined with bioinformatics analysis, we further confirmed that EIF4A3 contributes to the progress of GBM. RESULTS: The expression of EIF4A3 was upregulated in GBM tissues, and high expression of EIF4A3 is associated with poor prognosis in GBM. In vitro, knockdown of EIF4A3 significantly reduced the proliferation, migration, and invasion abilities of GBM cells, whereas overexpression of EIF4A3 led to the opposite effect. The analysis of differentially expressed genes related to EIF4A3 indicates that it is involved in many cancer-related pathways, such as Notch and JAK-STAT3 signal pathway. In Besides, we demonstrated the interaction between EIF4A3 and Notch1 by RNA immunoprecipitation. Finally, the biological function of EIF4A3-promoted GBM was confirmed in living organisms. CONCLUSION: The results of this study suggest that EIF4A3 may be a potential prognostic factor, and Notch1 participates in the proliferation and metastasis of GBM cells mediated by EIF4A3.


Assuntos
Glioblastoma , Adulto , Humanos , Glioblastoma/patologia , Transdução de Sinais/genética , Processos Neoplásicos , Prognóstico , Fatores de Iniciação de Peptídeos/metabolismo , Fator de Iniciação 4A em Eucariotos/genética , Fator de Iniciação 4A em Eucariotos/metabolismo , RNA Helicases DEAD-box/genética
4.
Ann Vasc Surg ; 92: 285-293, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36739079

RESUMO

BACKGROUND: We sought to find new biomarkers for abdominal aortic aneurysms (AAA) caused by chronic intermittent hypoxia (CIH). METHODS: The AAA mice model was created using Ang II. The mice were divided into normoxic and CIH groups. The structure of AAA was observed using abdominal ultrasonography, Elastica van Gieson (EVG), and hematoxylin and eosin (HE) staining. The expression of ɑ-SMA was investigated using immunohistochemistry. The novel biomarkers were screened using bioinformatics analysis. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to verify the expression of novel genes in both normal oxygen and CIH. RESULTS: CIH appears to cause greater aortic dilation, higher AAA incidence, lower survival rate, thicker vessel wall, and more brittle elastic lamellae when compared to controls. The immunohistochemistry results showed that the expression of ɑ-SMA in the CIH group was reduced significantly. Four novel genes, including Homer2, Robo2, Ehf, and Asic1, were found to be differentially expressed between normal oxygen and CIH using qRT-PCR, indicating the same trend as bioinformatics analysis. CONCLUSIONS: We discovered that CIH could hasten the occurrence and progression of AAA. Four genes (Homer2, Robo2, Ehf, and Asic1) may be novel biomarkers for AAA, which could aid in the search for new therapies for patients with AAA caused by CIH.


Assuntos
Aneurisma da Aorta Abdominal , Apneia Obstrutiva do Sono , Camundongos , Animais , Resultado do Tratamento , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/metabolismo , Imuno-Histoquímica , Oxigênio , Apneia Obstrutiva do Sono/genética , Apneia Obstrutiva do Sono/metabolismo , Modelos Animais de Doenças , Hipóxia/genética , Proteínas de Arcabouço Homer
5.
Environ Res ; 203: 111792, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333009

RESUMO

High-quality products in sustainable agriculture require both limited health risks and sufficient dietary nutrients. Phosphorus (P) as a finite and non-renewable resource is widely used in agriculture, usually exerting influence on the accumulation of heavy metals (HMs) in soil and crops. The present research explores, for the first time, the combined effects of long-term P fertilizer and repeated zinc (Zn) application in field on the human health risks and nutritional yield regarding trace elements in maize grain. A field experiment was conducted using maize with six P application rates (0, 12.5, 25, 50, 100, and 200 kg P ha-1) and two Zn application rates (0 and 11.4 kg Zn ha-1). The results showed that the concentrations of Zn, copper (Cu), and lead (Pb) in the maize grain were significantly affected by P application and can be further affected by Zn application. The concentrations of chromium (Cr) and arsenic (As) showed opposite tendency as affected by P fertilizer rates while did not affected by additional Zn application. Zn application decreased the cadmium (Cd) concentration at high P levels and Pb concentration at low P levels, particularly. No HMs contamination or direct health risk was found in maize grain after receiving long-term P and repeated Zn fertilizer. The threshold hazard quotient of an individual and all investigated HMs in this study were acceptable for human digestion of maize grain. While the carcinogenic risk of Cr was non-negligible in case of maize was taken as one of daily staple food for local residents. Combination use of P (25 kg ha-1) and Zn fertilizer on maize enhanced its nutritional supply ability regarding Zn and Cu, and simultaneously mitigated potential human health risks associated with Cd and Pb.


Assuntos
Metais Pesados , Poluentes do Solo , Agricultura , China , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Fósforo , Medição de Risco , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Zea mays
6.
Appl Opt ; 61(8): 2125-2139, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35297906

RESUMO

The spaceborne dispersive spectrometer is widely used in environmental, resource, and ocean observations. The coded spectrometer has higher energy advantages than the dispersion spectrometer, so it has great application prospects. In the current study, we developed an off-axis short-wave infrared coded optical system (SICOS) based on curved prism dispersion, and we further explored the design and optimization of the SICOS structure. Finite element analyses of a space-based short-wave infrared coded spectrometer based on curved prism dispersion (SSICS-CPD), including static simulation, modal analysis, sinusoidal vibration mechanical analysis, and random vibration mechanical analysis, were carried out. Simulation results showed that the SICOS support structure had excellent mechanical and thermal stability. As off-axis optical systems cannot meet the requirements of optical position accuracy through centering processing, a point source microscope and three-coordinate measuring machines were employed to complete the high-precision and rapid assembly of the SSICS-CPD. In addition, verification tests of surface shape error, stress relief, random vibration, and optical design parameters were carried out to validate the high stability and imaging performance of the SSICS-CPD. Results showed that the average modulation transfer function in the full field was 0.43 at 16.67 lp/mm, the spectral smile was <0.2 pixels, and the spectral keystone was <0.1 pixels. The design, analysis, assembly, and verification of the SSICS-CPD provide a useful reference for the development of other spaceborne prism dispersion spectrometers.

7.
J Med Internet Res ; 24(6): e37623, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35671411

RESUMO

BACKGROUND: During global health crises such as the COVID-19 pandemic, rapid spread of misinformation on social media has occurred. The misinformation associated with COVID-19 has been analyzed, but little attention has been paid to developing a comprehensive analytical framework to study its spread on social media. OBJECTIVE: We propose an elaboration likelihood model-based theoretical model to understand the persuasion process of COVID-19-related misinformation on social media. METHODS: The proposed model incorporates the central route feature (content feature) and peripheral features (including creator authority, social proof, and emotion). The central-level COVID-19-related misinformation feature includes five topics: medical information, social issues and people's livelihoods, government response, epidemic spread, and international issues. First, we created a data set of COVID-19 pandemic-related misinformation based on fact-checking sources and a data set of posts that contained this misinformation on real-world social media. Based on the collected posts, we analyzed the dissemination patterns. RESULTS: Our data set included 11,450 misinformation posts, with medical misinformation as the largest category (n=5359, 46.80%). Moreover, the results suggest that both the least (4660/11,301, 41.24%) and most (2320/11,301, 20.53%) active users are prone to sharing misinformation. Further, posts related to international topics that have the greatest chance of producing a profound and lasting impact on social media exhibited the highest distribution depth (maximum depth=14) and width (maximum width=2355). Additionally, 97.00% (2364/2437) of the spread was characterized by radiation dissemination. CONCLUSIONS: Our proposed model and findings could help to combat the spread of misinformation by detecting suspicious users and identifying propagation characteristics.


Assuntos
COVID-19 , Mídias Sociais , Comunicação , Humanos , Pandemias , SARS-CoV-2
8.
Zhongguo Zhong Yao Za Zhi ; 47(5): 1370-1382, 2022 Mar.
Artigo em Zh | MEDLINE | ID: mdl-35343166

RESUMO

This study explored the anticoagulant material basis and mechanism of Trichosanthis Semen and its shell and kernel based on spectrum-effect relationship-integrated molecular docking. High performance liquid chromatography(HPLC) fingerprints of Trichosanthis Semen and its shell and kernel were established. Prothrombin time(PT) and activated partial thromboplastin time(APTT) in mice in the low-and high-dose(5, 30 g·kg~(-1), respectively) Trichosanthis Semen, the shell, and kernel groups were determined as the coagulation markers. The spectrum-effect relationship and anticoagulant material basis of Trichosanthis Semen and its shell and kernel were analyzed with mean value calculation method of Deng's correlation degree(MATLAB) and the common effective component cluster was obtained. Then the common targets of the component cluster and coagulation were retrieved from TCMSP, Swiss-TargetPrediction, GenCLiP3, GeneCards, and DAVID, followed by Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment of the targets. The main anticoagulant molecular mechanism of the component cluster was verified by SYBYL-X 2.1.1. The spectrum-effect relationship of Trichosanthis Semen and its shell and kernel was in positive correlation with the dosage. The contribution of each component to anticoagulation was not the same, suggesting that the material basis for anticoagulation was different, but they have common effective components(i.e. common material basis), such as adenine(peak 3), uracil(peak 4), hypoxanthine(peak 6), xanthine(peak 9), and adenosine(peak 11). Network pharmacology showed that these components can act on multiple target proteins such as NOS3, KDR, and PTGS2, and exert anticoagulant effect through multiple pathways such as VEGF signaling pathway. They involved the biological functions such as proteolysis, cell component such as cytosol, and molecular functions. The results of molecular docking showed that the binding free energy of these components with NOS3(PDB ID: 1 D0 C), KDR(PDB ID: 5 AMN), and PTGS2(PDB ID: 4 COX) was ≤-5 kJ·mol~(-1), and the docking conformations were stable. Spectrum-effect relationship-integrated molecular docking can be used for the optimization, virtual screening, and verification of complex chemical and biological information of Chinese medicine. Trichosanthis Semen and its shell and kernel have the common material basis for anticoagulation and they exert the anticoagulant through multiple targets and pathways.


Assuntos
Anticoagulantes , Medicamentos de Ervas Chinesas , Animais , Anticoagulantes/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Ontologia Genética , Camundongos , Simulação de Acoplamento Molecular , Sêmen
9.
Zhongguo Zhong Yao Za Zhi ; 47(15): 4025-4032, 2022 Aug.
Artigo em Zh | MEDLINE | ID: mdl-36046891

RESUMO

The classical famous prescription Dajianzhong Decoction is recorded in Synopsis of the Golden Chamber written by Zhang Zhongjing in the Eastern Han Dynasty. It has a long history and definite clinical effects, while this prescription has not been manufactured into Chinese patent medicine preparation. We collected many ancient books of traditional Chinese medicine(TCM) by using the method of bibliometrics and got 211 valid data terms which involved 67 ancient books. The history, main treated syndromes, formulation principle, origins and processiong of medicinal materials, and decoction method of Dajianzhong Decoction were analyzed. Despite the different views of various generations of medical experts toward the composition of this prescription, the compatibility ratio of Ginseng Radix et Rhizoma to Zingiberis Rhizoma Recens is constant. Furthermore, we explored the origins of synonyms of Dajianzhong Decoction. On the basis of this study, we hope to gain an insight into the research and development of the compound preparations of Dajianzhong Decoction and provide reference for the heritage and innovation of other classical prescriptions.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Prescrições , Rizoma
10.
Mediators Inflamm ; 2021: 8856326, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33867859

RESUMO

Non-small-cell lung cancer (NSCLC) remains the most common malignancy with the highest morbidity and mortality worldwide. In our previous study, we found that a classic traditional Chinese medicine (TCM) formula Ze-Qi-Tang (ZQT), which has been used in the treatment of respiratory diseases for thousands of years, could directly inhibit the growth of human NSCLC cells via the p53 signaling pathway. In this study, we explored the immunomodulatory functions of ZQT. We found that ZQT significantly prolonged the survival of orthotopic lung cancer model mice by modulating the tumor microenvironment (TME). ZQT remarkably reduced the number of MDSCs (especially G-MDSCs) and inhibited their immunosuppressive activity by inducing apoptosis in these cells via the STAT3/S100A9/Bcl-2/caspase-3 signaling pathway. When G-MDSCs were depleted, the survival promotion effect of ZQT and its inhibitory effect on lung luminescence signal disappeared in tumor-bearing mice. This is the first study to illustrate the immunomodulatory effect of ZQT in NSCLC and the underlying molecular mechanism.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Granulócitos/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Medicina Tradicional Chinesa , Células Supressoras Mieloides/efeitos dos fármacos , Animais , Calgranulina B/fisiologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Caspase 3/fisiologia , Linhagem Celular Tumoral , Medicamentos de Ervas Chinesas/uso terapêutico , Granulócitos/patologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos C57BL , Células Supressoras Mieloides/patologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Fator de Transcrição STAT3/fisiologia , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral
11.
Mol Phylogenet Evol ; 152: 106939, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32791299

RESUMO

Ottelia Pers. is the second largest genus of the family Hydrocharitaceae, including approximately 23 extant species. The genus exhibits a diversity of both bisexual and unisexual flowers, and complex reproductive system comprising cross-pollinated to cleistogamous flowers. Ottelia has been regarded as a pivotal group to study the evolution of Hydrocharitaceae, but the phylogenic relationships and evolutionary history of the genus remain unresolved. Here, we reconstructed a robust phylogenetic framework for Ottelia using 40 newly assembled complete plastomes. Our results resolved Ottelia as a monophyletic genus consisting of two major clades, which correspond to the main two centers of diversity in Asia and Africa. According to the divergence time estimation analysis, the crown group Ottelia began to diversify around 13.09 Ma during the middle Miocene. The biogeographical analysis indicated the existence of the most recent common ancestor somewhere in Africa/Australasia/Asia. Basing on further insights from the morphological evolution of Ottelia, we hypothesized that the ancestral center of origin was in Africa, from where the range expanded by transoceanic dispersal to South America and Australasia, and further from Australasia to Asia. We suggested that the climatic change and global cooling since the mid-Miocene, such as the development of East Asian monsoon climate and tectonic movement of the Yunnan-Guizhou Plateau (YGP), might have played a crucial role in the evolution of Ottelia in China.


Assuntos
Hydrocharitaceae/classificação , Hydrocharitaceae/genética , Filogenia , Evolução Biológica , Filogeografia , Plastídeos/genética
12.
Org Biomol Chem ; 18(20): 3908-3916, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32400796

RESUMO

Six undescribed steroids were isolated from the fungus Inonotus obliquus. Notably, compounds 1 and 2 represented the first example of 8,14-seco-4-methylpregnane. By spectroscopic data analyses, quantum chemical calculations and DP4+ probability analysis, their structures were unambiguously determined. The absolute configurations of the compounds 1-6 were defined by comparison of their experimental and calculated electronic circular dichroism (ECD) spectra data. The structure of compound 1 was also confirmed by single-crystal X-ray diffraction. All isolated steroids were evaluated for their neuroprotective activities against H2O2-induced cell injury in human neuroblastoma SH-SY5Y cells, among which compound 2 showed moderate activity at 12.5 µM.


Assuntos
Peróxido de Hidrogênio/antagonistas & inibidores , Inonotus/química , Fármacos Neuroprotetores/farmacologia , Esteroides/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Peróxido de Hidrogênio/farmacologia , Modelos Moleculares , Conformação Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Esteroides/química , Esteroides/isolamento & purificação
13.
Exp Cell Res ; 378(2): 139-148, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30826396

RESUMO

The objective of this study was to investigate the functional role of Rab39a in human cervical cancer (CC) and the underlying molecular mechanisms. We first measured Rab39a mRNA expression in CC tissues and paired non-tumor tissues by quantitative real-time PCR (QRT-PCR). Overall survival of CC patients with different mRNA levels of Rab39a in The Cancer Genome Atlas (TCGA) database was assessed by Kaplan-Meier survival curves analysis. Next methylation-specific PCR (MSP) was performed to determine the expression mechanism of Rab39a. Then cell proliferation, migration and invasion of Rab39a-transfected or mock-transfected cervical cancer cells were determined by CCK-8, flow cytometry, wound healing, transwell migration and invasion assays, respectively. Finally, the molecular mechanism by which Rab39a modulated CC cell epithelial-mesenchymal transition (EMT) was explored. It was found that Rab39a mRNA was significantly down-regulated in the high-risk patients compared to the low-risk patients (p = 0.0054). Six of seven cancer tissues with lymph node metastasis express low Rab39a mRNA compared to the surrounding non-tumor tissues. Cervical cancer patients with low level of Rab39a were showed a poorly clinical outcome (p = 0.004). Loss of Rab39a expression in cervical cancer tissues was associated with the aberrant DNA methylation in the promoter of Rab39a gene. Disrupted Rab39a expression in cervical cancer cells could be restored after treatment with the demethylated agent 5-Aza-2'-deoxycytidine. Furthermore, it was found that Rab39a hardly influenced cell growth but significantly suppressed cell migration, invasion and EMT process. Rab39a exerted its potential suppressor functions through inhibiting AKT phosphorylation. The inhibition effects of Rab39a could be blocked by AKT pathway inhibitor. Collectively, our data shows that Rab39a is a potential epigenetic silenced tumor suppressor inhibiting cancer invasion and migration through modulating the AKT signaling.


Assuntos
Epigênese Genética , Transição Epitelial-Mesenquimal/genética , Inativação Gênica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/genética , Neoplasias do Colo do Útero/genética , Proteínas rab de Ligação ao GTP/genética , Linhagem Celular Tumoral , Movimento Celular , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metilação , Proteínas Supressoras de Tumor/metabolismo , Neoplasias do Colo do Útero/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
14.
Bioorg Chem ; 105: 104438, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33171406

RESUMO

Six undescribed lanostane triterpenoids (1-6), together with three known compounds (7-9) were isolated from Inonotus obliquus. Compounds 3-5 are the rare natural compounds featuring a 4,5-seco-lanostane core with a 5,7,9-trien-21,24-cyclopentane moiety. The structure elucidation of the compounds was conducted by spectroscopic techniques and the ECD method. The absolute configuration of compound 1 was confirmed by single-crystal X-ray diffraction analysis. All isolated compounds were assayed for their neuroprotective activity against H2O2-induced cell injury using human neuroblastoma SH-SY5Y cells. Compound 9 exhibited the most potent neuroprotective activity and the flow cytometry analysis indicated that 9 could protect SH-SY5Y cells from oxidative damage by inhibiting cell apoptosis.


Assuntos
Antineoplásicos/química , Misturas Complexas/química , Inonotus/química , Lanosterol/química , Neuroblastoma/tratamento farmacológico , Fármacos Neuroprotetores/química , Triterpenos/química , Antineoplásicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida , Misturas Complexas/farmacologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Peróxido de Hidrogênio/metabolismo , Conformação Molecular , Estrutura Molecular , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Triterpenos/farmacologia
15.
Bioorg Chem ; 96: 103588, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32032845

RESUMO

A pair of new flavan derivative enantiomers (1a and 1b), four new drimane sesquiterpene lactones (2-5) and a known compound (6) were isolated from Inonotus obliquus. Their structures were determined by comprehensive spectroscopic analyses. Compounds 1a/1b were separated by chiral chromatographic column successfully. The absolute configurations of compounds 1-5 were determined by comparison of their experimental and calculated ECD spectra. Notably, compounds 1a/1b represented the first pair of enantiomers in nature with tetrahydrofuran-flavan skeleton. A plausible biosynthetic pathway for (±)-1 was also proposed. All isolates were evaluated for their neuroprotective activities against H2O2-induced cell injury in SH-SY5Y cells. The results showed that compound 2 exhibited moderate neuroprotective activity at the concentration of 25.0 µM.


Assuntos
Inonotus/química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Sesquiterpenos Policíclicos/química , Sesquiterpenos Policíclicos/farmacologia , Linhagem Celular , Flavonoides/química , Flavonoides/farmacologia , Humanos , Lactonas/química , Lactonas/farmacologia , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estereoisomerismo
16.
J Nat Prod ; 82(4): 714-723, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917277

RESUMO

Quassinoids are a class of highly oxygenated degraded triterpenoids exclusively discovered from plants of the Simaroubaceae family. In this study, eight new (1-8) and 15 known quassinoids (9-23) were isolated from an extract of the stems of Picrasma quassioides. The structures were elucidated by spectroscopic analysis and electronic circular dichroism spectra combined with quantum chemical calculations. Compounds 4 and 5 represent the first examples of 18-nor-quassinoids from P. quassioides. All isolates were screened for their neuroprotective activities toward H2O2-induced cell damage in SH-SY5Y cells. Further study revealed that the potential protective activities of these compounds appeared to occur via the suppression of cell apoptosis and downregulation of caspase-3 activation.


Assuntos
Fármacos Neuroprotetores/farmacologia , Picrasma/química , Quassinas/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Tumoral , Humanos , Peróxido de Hidrogênio/toxicidade , Estrutura Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Espectroscopia de Prótons por Ressonância Magnética , Quassinas/química , Quassinas/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray
17.
Bioorg Chem ; 84: 309-318, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30530072

RESUMO

Seven new tirucallane-type triterpenoids (1-7), kumuquassin A-G, along with 20 known analogues (8-27) were isolated from the stems of Picrasma quassioides. The structures and the absolute configurations of new compounds were elucidated by spectroscopic data, electronic circular dichroism (ECD) spectroscopic analyses and quantum ECD calculations. Notably, kumuquassin A (1) contains a rare Δ17, 20 double bond, kumuquassin B (2) is the first example of tirucallane triterpenoid possessing a 5/3 biheterocyclic ring system at the side chain. All the compounds were screened for the cytotoxicity against two human hepatoma cell lines, HepG2 and Hep3B, and several compounds exhibited promising activity. The most potential compound 3 was selected for cell cycle analysis, which showed that 3 could cause an accumulation of HepG2 cells at subG1 peak. Annexin V-FITC/PI staining further confirmed that compound 3 caused death of hepatoma cells through apoptosis induction.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Picrasma/química , Triterpenos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Conformação Molecular , Picrasma/metabolismo , Caules de Planta/química , Caules de Planta/metabolismo , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
18.
Planta Med ; 85(8): 648-656, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30974464

RESUMO

Four pairs of ß-carboline enantiomers (1A: /1B: -4A: /4B: ), 2 ß-carboline derivatives (5:  - 6: ) with a single enantiomeric configuration, together with 2 known achiral congeners (7:  - 8: ) were isolated from the stems of Picrasma quassioides. Their structures were elucidated on the basis of extensive spectroscopic analyses and quantum mechanical calculations. Compound 5: possesses a 4,5-seco ß-carboline framework and represents the first example of this type of ß-carboline alkaloids from nature. A possible biosynthetic pathway is proposed to generate the racemate 4: and the enantiomerically pure compounds 5: and 6: . All isolates were screened for their cytotoxicity against hepatocellular carcinoma Hep3B and HepG2 cells, which revealed that enantiomeric compounds 4A: and 4B: had distinctive effects in HepG2 cells. Further investigation showed that 4B: could induce apoptosis in HepG2 cells.


Assuntos
Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Carbolinas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Picrasma/química , Alcaloides/química , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Carbolinas/química , Carbolinas/farmacologia , Cromatografia , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Estrutura Molecular , Estereoisomerismo
19.
Zhongguo Zhong Yao Za Zhi ; 44(8): 1654-1659, 2019 Apr.
Artigo em Zh | MEDLINE | ID: mdl-31090331

RESUMO

To explore the anti-platelet aggregation and anti-thrombotic mechanisms of Trichosanthis Fructus combined with aspirin based on network pharmacology and the validation of arteriovenous by pass model in rats. The databases of Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP),Drug Repositioning and Adverse Drug Reaction Chemical-Protein Interactome(DRAR-CPI),Universal Protein Resource(Uniprot) and the Database for Annotation,Visualization,and Integrated Discovery(DAVID) were used to predict protein targets and analyze biological pathway and signal pathway in the combination of Trichosanthis Fructus with aspirin. The effects of pretreatment with Trichosanthis Fructus pellets,aspirin pellets and their combination on thromboxane B2(TXB2),6-keto prostaglandin F1α(6-keto-PGF1α) and cyclic adenosine monophosphate(c AMP) in rat thrombotic model were studied. Through the study of network pharmacology,12 components of aspirin and Trichosanthis Fructus,including hydroxygenkwanin,quercetin and adenosine,were found to show the anti-platelet aggregation and anti-thrombosis mechanisms through9 common protein targets,such as SRC,RAC1,MAPK14,MAPK1,AKT1,and 14 common signaling pathways,such as VEGF signaling pathway. After the intervention with Trichosanthis Fructus pellets combined with aspirin pellets,the vascular endothslia growth factor(VEGF) signaling pathway can be activated to inhibit platelet aggregation and improve vascular endothelial function,and show the anti-platelet aggregation and anti-thrombosis mechanisms,which verify the results of the network pharmacology,and explain the anti-platelet aggregation and anti-thrombotic mechanisms of the combination of Trichosanthis Fructus pellets with aspirin pellets.


Assuntos
Aspirina/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Trombose/tratamento farmacológico , Trichosanthes/química , 6-Cetoprostaglandina F1 alfa/metabolismo , Animais , AMP Cíclico/metabolismo , Frutas/química , Ratos , Transdução de Sinais , Tromboxano B2/metabolismo
20.
Plant Cell Physiol ; 59(4): 756-764, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29186581

RESUMO

Plants are known for their capacity to regenerate organs, such as shoot, root and floral organs. Recently, a number of studies contributed to understanding the mechanisms of shoot and root regeneration. However, the mechanisms underlying floral organ regeneration are largely unknown. In this study, we established a carpel regeneration system in which two types of carpels were induced by exogenous cytokinin. For type I, all the floral organs in the regenerated inflorescence were transformed into carpels. For type II, carpels were generated directly from callus. The transcript level of AGAMOUS (AG), the carpel identity gene, was up-regulated during carpel induction. The expression signals of AG were detected in the initiating carpel primordia and regenerating carpels, and co-localized with those of two Type-B ARABIDOPSIS RESPONSE REGULATORs (ARRs), ARR1 and ARR10. Repression of either AG or type-B ARRs reduced carpel regeneration. Binding analyses showed that ARR1 and ARR10 directly bound to transcriptional regulatory regions of AG and positively regulated its expression. In addition, the expression of type-B ARRs overlapped with that of AG in the floral primordia in planta. Defects in type-B ARRs reduced the number of carpels. The results indicate that type-B ARRs control carpel regeneration through activating AG expression. Our results provide new information for understanding the mechanism of carpel formation.


Assuntos
Proteína AGAMOUS de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Ligação a DNA/metabolismo , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Regeneração , Fatores de Transcrição/metabolismo , Proteína AGAMOUS de Arabidopsis/metabolismo , Reprogramação Celular/efeitos dos fármacos , Citocininas/farmacologia , Flores/genética , Regeneração/efeitos dos fármacos
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