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1.
Phytochemistry ; 212: 113728, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37211335

RESUMO

Cinnamigones A-C, three undescribed highly oxidized guaiane-type sesquiterpenes were isolated from the fruits of Cinnamomum migao. Cinnamigone A (1), structurally artemisinin-like, is a natural 1,2,4-trioxane caged endoperoxide with an unprecedented tetracyclic 6/6/7/5 ring system. Compounds 2-3 are classic guaiane sesquiterpene featuring different epoxy units. Guaiol (4) is considered to be the precursor of 1-3 in the biosynthesis pathway hypothesis. The planar structures and configurations of cinnamigones A-C were elucidated by spectral analysis, HRESIMS, X-ray crystallography and ECD calculations. Evaluation of the neuroprotective activity of 1-3 on N-methyl-ᴅaspartate (NMDA) toxicity was demonstrated that compounds 1-2 exhibited moderate neuroprotective activity against NMDA-induced neurotoxicity.


Assuntos
Cinnamomum , Sesquiterpenos , Estrutura Molecular , N-Metilaspartato , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Sesquiterpenos de Guaiano/farmacologia
2.
J Pharmacol Exp Ther ; 369(1): 121-128, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30837279

RESUMO

Icariin (ICA), a major flavonoid extracted from the Chinese tonic herb Epimedium, exerts beneficial effects in a variety of age-dependent diseases, such as Alzheimer's disease (AD). However, the antiaging mechanisms remain unclear. The senescence-accelerated mouse-prone 8 (SAMP8) model has been used to study age-related neurodegenerative changes associated with aging and the pathogenesis of AD. Hence, the current study was designed to examine the effect of ICA on age-related cognitive decline in SAMP8 mice and explore the role of autophagy in the ICA-mediated neuroprotection. SAMP8 mice were administered with ICA starting at 5 months of age, and the treatment lasted for 3 consecutive months. Morris water maze was used to evaluate cognitive function. The senescence-associated ß-galactosidase staining was used to determine the number of senescence cells. The neuronal morphologic changes were examined via Nissl staining. The hippocampal neuronal ultrastructure was examined by transmission electron microscopy. The expression of autophagy protein was examined by Western blot. ICA-treated SAMP8 mice exhibited a robust improvement in spatial learning and memory function. Meanwhile, ICA reduced the number of senescence cells in the brains of SAMP8 mice, inhibited neuronal loss, and reversed neuronal structural changes in the hippocampi of SAMP8 mice. Moreover, ICA treatment also decreased the formation of autophagosomes in the hippocampus of SAMP8 mice, and reduced the expression of autophagy-related proteins LC3-II and p62. These results demonstrate that ICA possesses the ability to delay brain aging in SAMP8 mice, and the mechanisms are possibly mediated through the regulation of autophagy.


Assuntos
Envelhecimento/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Flavonoides/farmacologia , Animais , Encéfalo/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Memória/efeitos dos fármacos , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Modelos Animais
3.
Plant Sci ; 241: 277-85, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26706078

RESUMO

Magnolia stellata is a woody ornamental shrub with more petaloid tepals than related plants from family Magnoliaceae. Recent studies revealed that expression changes in an AGAMOUS (AG) orthologous gene could resulted in double flowers with increased numbers of petals. We isolated three transcripts encoding different isoforms of a single AG orthologous gene, MastAG, mastag_2 and mastag_3, from M. stellata. Sequence alignments and Southern blot analyses suggested that MastAG was a single-copy gene in M. stellata genomes, and that mastag_2 and mastag_3 were abnormally spliced isoforms of MastAG. An 144bp exon skipping in MastAG results in the truncated mastag_2 protein lacking the completely I domain and 18 aa of the K1 subdomain, whereas an 165bp exon skipping of MastAG produces a truncated mastag_3 protein lacking 6 aa of the K3 subdomain and the completely C terminal region. Expression analyses showed that three alternative splicing (AS) isoforms expressed only in developing stamens and carpels. Functional analyses revealed that MastAG could mimic the endogenous AG to specify carpel identity, but failed to regulate stamen development in an Arabidopsis ag-1 mutant. Moreover, the key domain or subdomain deletions represented by mastag_2 and mastag_3 resulted in loss of C-function. However, ectopic expression of mastag_2 in Arabidopsis produced flowers with sepals converted into carpeloid organs, but without petals and stamens, whereas ectopic expression of mastag_3 in Arabidopsis could mimic the flower phenotype of the ag mutant and produced double flowers with homeotic transformation of stamens into petals and carpels into another ag flower. Our results also suggest that mastag_3 holds some potential for biotechnical engineering to create multi-petal phenotypes in commercial ornamental cultivars.


Assuntos
Processamento Alternativo , Regulação da Expressão Gênica de Plantas , Proteínas de Domínio MADS/genética , Magnolia/genética , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Flores/genética , Flores/metabolismo , Proteínas de Domínio MADS/metabolismo , Magnolia/metabolismo , Filogenia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Alinhamento de Sequência
4.
Anal Biochem ; 426(2): 118-25, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22507376

RESUMO

Among the components that make up a lateral-flow immunochromatographic assay (ICA), antibody is the key. In this paper, salbutamol (SAL) as a model analyte was meticulously designed to prepare immunogen and coating antigen in distinctly different ways. Four hybridoma cell lines were prepared and identified. Among them, C9 had highest affinity, best dose-response behavior, lowest limit of detection, and highest specificity and was chosen to be labeled with colloidal gold as the detector reagent and applied on the conjugate pad. Goat anti-mouse antibody and SAL-BSA conjugate were sprayed on a nitrocellulose membrane as test line and control line, respectively. Under the optimized conditions, the ICA strip was constructed based on a binding inhibition format. Color intensity on the test line was visually distinguishable from that of the negative sample within 5 min, with the visual detection limit of 1 ngml(-1) in phosphate-buffered saline. Cross-reactions with other ß-agonists were not found (<1%). The results from ICA were in a good agreement with those obtained by enzyme-linked immunosorbent assay. The developed ICA has potential as a useful on-site screening tool for SAL in swine urine.


Assuntos
Albuterol/urina , Anticorpos Monoclonais/imunologia , Cromatografia de Afinidade , Agonistas Adrenérgicos beta/química , Albuterol/química , Albuterol/imunologia , Animais , Bovinos , Linhagem Celular , Reações Cruzadas , Feminino , Ouro/química , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/química , Ovalbumina/imunologia , Soroalbumina Bovina/química , Soroalbumina Bovina/imunologia , Suínos
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