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1.
Phytochemistry ; 231: 114357, 2024 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-39662694

RESUMO

Five brasilane-type sesquiterpenoids, including four previously undescribed compounds named xylaribrasilaids A-D, along with a known analogue, were isolated from the ethyl acetate extracts of solid fermentation from Xylaria nigripes. X. nigripes, a traditional Chinese medicinal fungus utilized for treating various ailments such as insomnia, trauma, and depression, has garnered attention due to its pharmacological potential. Their structures and absolute configurations were elucidated through comprehensive spectroscopic analysis, including NMR, HRESIMS, and experimental ECD data. In vitro bioassays were conducted to assess the neuroprotective activities of these compounds against glutamate-induced damage in PC12 cells. Remarkably, all isolated compounds demonstrated significant enhancements in cell viability while concurrently inhibiting apoptosis. Moreover, they effectively attenuated oxidative stress markers, as evidenced by increased activities of superoxide dismutase and glutathione. Furthermore, these compounds displayed the capacity to mitigate intracellular reactive oxygen species accumulation, highlighting their potential in combating oxidative stress-related neurodegenerative disorders.

2.
Front Cell Infect Microbiol ; 13: 1221246, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38035328

RESUMO

Introduction: Farnesol, derived from farnesyl pyrophosphate in the sterols biosynthetic pathway, is a molecule with three unsaturations and four possible isomers. Candida albicans predominantly secretes the trans, trans-farnesol (t, t-FOH) isomer, known for its role in regulating the virulence of various fungi species and modulating morphological transition processes. Notably, the evolutionary divergence in sterol biosynthesis between fungi, including Candida albicans, and trypanosomatids resulted in the synthesis of sterols with the ergostane skeleton, distinct from cholesterol. This study aims to assess the impact of exogenously added trans, trans-farnesol on the proliferative ability of Leishmania amazonensis and to identify its presence in the lipid secretome of the parasite. Methods: The study involved the addition of exogenous trans, trans-farnesol to evaluate its interference with the proliferation of L. amazonensis promastigotes. Proliferation, cell cycle, DNA fragmentation, and mitochondrial functionality were assessed as indicators of the effects of trans, trans-farnesol. Additionally, lipid secretome analysis was conducted, focusing on the detection of trans, trans-farnesol and related products derived from the precursor, farnesyl pyrophosphate. In silico analysis was employed to identify the sequence for the farnesene synthase gene responsible for producing these isoprenoids in the Leishmania genome. Results: Exogenously added trans, trans-farnesol was found to interfere with the proliferation of L. amazonensis promastigotes, inhibiting the cell cycle without causing DNA fragmentation or loss of mitochondrial functionality. Despite the absence of trans, trans-farnesol in the culture supernatant, other products derived from farnesyl pyrophosphate, specifically α-farnesene and ß-farnesene, were detected starting on the fourth day of culture, continuing to increase until the tenth day. Furthermore, the identification of the farnesene synthase gene in the Leishmania genome through in silico analysis provided insights into the enzymatic basis of isoprenoid production. Discussion: The findings collectively offer the first insights into the mechanism of action of farnesol on L. amazonensis. While trans, trans-farnesol was not detected in the lipid secretome, the presence of α-farnesene and ß-farnesene suggests alternative pathways or modifications in the isoprenoid metabolism of the parasite. The inhibitory effects on proliferation and cell cycle without inducing DNA fragmentation or mitochondrial dysfunction raise questions about the specific targets and pathways affected by exogenous trans, trans-farnesol. The identification of the farnesene synthase gene provides a molecular basis for understanding the synthesis of related isoprenoids in Leishmania. Further exploration of these mechanisms may contribute to the development of novel therapeutic strategies against Leishmania infections.


Assuntos
Leishmania mexicana , Leishmania , Farneseno Álcool/metabolismo , Farneseno Álcool/farmacologia , Leishmania mexicana/metabolismo , Leishmania/metabolismo , Esteróis/análise , Esteróis/farmacologia , Candida albicans
3.
Int J Biol Macromol ; 209(Pt B): 1784-1791, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35504416

RESUMO

The biosynthesis of brasilane-type sesquiterpenoids (BTSs) attracts much attention owing to their unique skeleton of 5/6 bicyclic structure that contains five Me groups. Here, the crystal structures of a BTS cyclase TaTC6 from Trichoderma atroviride FKI-3849 and its complexes with farnesyl pyrophosphate (FPP) and analogue were reported. These structural information reveal that TaTC6 exploits a hydrophobic pocket to constrain the hydrocarbon region of FPP in a "U-shape" to facilitate the initial C1-C11 bond formation after pyrophosphate ionization. Following, four carbocations of reaction intermediates were molecularly docked into the hydrophobic pocket to reveal critical residues involved in the cyclization cascade. Finally, an S239-stabilized water molecule that is 3.9 Å away from the C8 of the last allyl cation may conduct hydration to quench the reaction cascade. Mutating S239 to alanine led to ca. 40% reduction in activity compared with the wild-type enzyme. The conservation of the residues that constitute the hydrophobic pocket is also discussed. Overall, this study will give an insight into the mechanism of how the active site of STCs constrain the conformation of the flexible FPP and series allylic carbocations for the complicated-ring formation and unusual carbon rearrangement in the biosynthesis of BTSs.


Assuntos
Sesquiterpenos , Domínio Catalítico , Ciclização , Sesquiterpenos/química
4.
Bol. latinoam. Caribe plantas med. aromát ; 19(6): 527-541, 2020. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1284290

RESUMO

The genus Lindera consists of approximately 100 species that are widely distributed in tropical and subtropical areas throughout the world. Most Lindera plants, particularly Lindera aggregata is a well-known traditional Chinese medicine that has important medicinal value and health benefits. Contemporary chemical and pharmacological studies have shown that L. aggregata are a source of structurally diverse molecules having pharmacological potential. In an effort to promote research on L. aggregata and develop therapeutic and pharmacological products, this review describes the structural diversity of its components and pharmacological and biological significance of L. aggregata. This review is based on a literature analysis of scientific journals from electronic sources, such as Science Direct, PubMed, Google Scholar, Scopus and Web of Science. Thus, with the growing interest in traditional medicine and botanical drugs worldwide, L. aggregata will increasingly capture chemists' and pharmacologists' attention because they produce diverse and structurally novel compounds having pharmacological significance.


El género Lindera consta de aproximadamente 100 especies que están ampliamente distribuidas en áreas tropicales y subtropicales en todo el mundo. La mayoría de las plantas de Lindera, particularmente Lindera aggregata, es parte conocida de la medicina tradicional china con un importante valor medicinal y beneficios para la salud. Estudios químicos y farmacológicos contemporáneos han demostrado que L. aggregata es una fuente de moléculas estructuralmente diversas que con potencial farmacológico. En un esfuerzo por promover la investigación sobre L. aggregata y desarrollar productos terapéuticos y farmacológicos, esta revisión describe la diversidad estructural de sus componentes y la importancia farmacológica y biológica de L. aggregata. Esta revisión se basa en un análisis de literatura de revistas científicas de fuentes electrónicas, como Science Direct, PubMed, Google Scholar, Scopus y Web of Science. Por lo tanto, con el creciente interés en la medicina tradicional y las drogas botánicas en todo el mundo, L. aggregata captará cada vez más la atención de los químicos y farmacólogos debido a que producen compuestos diversos y estructuralmente novedosos que tienen importancia farmacológica.


Assuntos
Produtos Biológicos , Lindera/química , Compostos Fitoquímicos/análise , Sesquiterpenos/análise , Óleos Voláteis/química , Lauraceae/química , Alcaloides/análise , Compostos Fenólicos/análise , Fitoterapia , Medicina Tradicional
5.
Molecules ; 20(8): 14611-20, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26274948

RESUMO

Brasilamides K-N (1-4), four new bergamotane sesquiterpenoids; with 4-oxatricyclo (3.3.1.0 (2,7))nonane (1)and 9-oxatricyclo(4.3.0.0 (4,7))nonane (2-4) skeletons; were isolated from the scale-up fermentation cultures of the plant endophytic fungus Paraconiothynium brasiliense Verkley. The previously identified sesquiterpenoids brasilamides A and C (5 and 6) were also reisolated in the current work. The structures of 1-4 were elucidated primarily by interpretation of NMR spectroscopic data. The absolute configurations of 1-3 were deduced by analogy to the co-isolated metabolites 5 and 6; whereas that of C-12 in 4 was assigned using the modified Mosher method. The cytotoxicity of all compounds against a panel of eight human tumor cell lines were assayed.


Assuntos
Ascomicetos/química , Dioxóis/isolamento & purificação , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Linhagem Celular Tumoral , Dioxóis/química , Dioxóis/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Endófitos/química , Humanos , Espectroscopia de Ressonância Magnética/métodos , Piperazinas/química , Piperazinas/isolamento & purificação , Piperazinas/farmacologia , Sesquiterpenos/isolamento & purificação
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