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1.
Mol Phylogenet Evol ; 173: 107507, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35589053

RESUMO

Different from the generally conserved plastomes (plastid genomes) of most land plants, the Selaginellaceae plastomes exhibit dynamic structure, high GC content and high substitution rates. Previous plastome analyses identified strong conflict on several clades in Selaginella, however the factors causing the conflictions and the impact on the phylogenetic inference have not been sufficiently investigated. Here, we dissect the distribution of phylogenetic signals and conflicts in Selaginella sanguinolenta group, the plastome of which is DR (direct repeats) structure and with genome-wide RNA editing. We analyzed the data sets including 22 plastomes representing all species of the S. sanguinolenta group, covering the entire geographical distribution from the Himalayas to Siberia and the Russian Far East regions. We recovered four different topologies by applying multispecies coalescent (ASTRAL) and concatenation methods (IQ-TREE and RAxML) on four data sets of PC (protein-coding genes), NC (non-coding sequences), PCN (the concatenated PC and NC), and RC (predicted RNA editing sites "C" were corrected by "T"), respectively. Six monophyletic clades, S. nummularifolia clade, S. rossii clade, S. sajanensis clade, S. sanguinolenta I clade, S. sanguinolenta II clade, and S. sanguinolenta III clade, were consistently resolved and supported by the characteristics of GC content, RNA editing frequency, and gene content. However, the relationships among these clades varied across the four topologies. To explore the underlying causes of the uncertainty, we compared the phylogenetic signals of the four topologies. We identified that the sequence types (coding versus non-coding), outlier genes (genes with extremely high |ΔGLS| values), and C-to-U RNA editing frequency in the protein-coding genes were responsible for the unstable phylogenomic relationship. We further revealed a significant positive correlation between the |ΔGLS| values and the variation coefficient of the RNA editing number. Our results demonstrated that the coalescent method performed better than the concatenation method in overcoming the problems caused by outlier genes and extreme RNA editing events. Our study particularly focused on the importance of exploring the plastid phylogenomic conflicts and suggested conducting concatenated analyses cautiously when adopting organelle genome data.


Assuntos
Genomas de Plastídeos , Selaginellaceae , Evolução Molecular , Filogenia , Plastídeos/genética , Edição de RNA , Selaginellaceae/genética
2.
Phytomedicine ; 100: 154065, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35358932

RESUMO

BACKGROUND: Doxorubicin (DOX) is a highly effective chemotherapeutic that is effective for various tumours. However, the clinical application of DOX has been limited by adverse reactions such as cardiotoxicity and heart failure. Since DOX-induced cardiotoxicity is irreversible, drugs to prevent DOX-induced cardiotoxicity are needed. PURPOSE: This study aimed to investigate the effect of total flavonoids of Selaginella tamariscina (P.Beauv.) Spring (TFST) on doxorubicin-induced cardiotoxicity. METHODS: The present study established DOX-induced cardiotoxicity models in C57BL/6 mice treated with DOX (cumulative dose: 20 mg/kg body weight) and H9c2 cells incubated with DOX (1 µM/l) to explore the intervention effect and potential mechanism of TFST. Echocardiography was performed to evaluate left ventricular functions. Heart tissue samples were collected for histological evaluation. Myocardial injury markers and oxidative stress markers were examined. Mitochondrial energy metabolism pathway associated proteins PPARα/PGC-1α/Sirt3 were detected. We also explored the effects of TFST on endoplasmic reticulum (ER) stress and apoptosis. To further investigate the protective mechanism of TFST, we used the specific small interfering RNA MFN2 (siMFN2) to explore the effect of MFN2 on TFST against DOX-induced cardiotoxicity in vitro. Flow cytometry detected reactive oxygen species, mitochondrial membrane potential and apoptosis. Cell mitochondrial stress was measured by Seahorse XF analyser. RESULTS: Both in vivo and in vitro studies verified that TFST observably alleviated DOX-induced mitochondrial dysfunction and ER stress. However, these effects were reversed after transfected siMFN2. CONCLUSION: Our results indicated that TFST ameliorates DOX-induced cardiotoxicity by alleviating mitochondrial dysfunction and ER stress by activating MFN2/PERK. MFN2/PERK pathway activation may be a novel mechanism to protect against DOX-induced cardiotoxicity.


Assuntos
Cardiotoxicidade , Selaginellaceae , Animais , Apoptose , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/metabolismo , Doxorrubicina/farmacologia , Estresse do Retículo Endoplasmático , Flavonoides/farmacologia , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias , Miócitos Cardíacos , Estresse Oxidativo
3.
J Chromatogr A ; 1668: 462920, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35248869

RESUMO

Herein, a novel covalent organic polymers (COP) material based on acylhydrazone bond (AB-COP) was prepared as an efficient extraction material for enriching natural medicine biflavonoids from Selaginella doederleinii Hieron. The obtained AB-COP structure was characterized in detail. And it was the first time to investigate the effect of AB-COP on the adsorption of biflavonoids. The effects of initial concentration of solution, adsorption temperature, solid-liquid ratio, adsorption time on the adsorption of biflavonoids were studied. In addition, adsorption kinetic model, adsorption thermodynamic model and density functional theory (DFT) were also investigated to evaluate the adsorption mechanism. At the same time, the static desorption and reusability of AB-COP were investigated. Finally, the dynamic enrichment effect of AB-COP for biflavonoids was investigated. The results showed that AB-COP was successfully synthesized by Fourier transform infrared spectroscopy (FT-IR), solid state nuclear magnetism (NMR), X-ray diffraction (XRD), thermogravimetric analysis (TG), scanning electron microscopy (SEM), laser particle size analysis and Brunner Emmet Teller (BET) specific surface area test. The optimized adsorption parameters of AB-COP were initial concentration of 0.5 mg/mL, temperature of 45 °C, solid-liquid ratio of 10:10 (mg/mL), adsorption time of 60 min. The Langmuir adsorption isotherm could effectively describe the adsorption process, the pseudo-secondary adsorption model could accurately explain the adsorption mechanism, and the DFT calculations revealed that the interaction forces of AB-COP and biflavonoids were π-π stacking and hydrogen bonding. In addition, AB-COP successfully resolved biflavonoids through urea-methanol (1.3 mol/L), and the material can be reused at least four times. Finally, the solid phase extraction (SPE) chromatographic column prepared by AB-COP was successfully applied to the enrichment of biflavonoids from S. doederleinii, and the effect was significantly better than traditional chromatography materials, andthis method was also successfully applied to the enrichment of flavonoids in other plant extracts including Flos sophorae, Pericarpium viride, Lophatheri herba, Herba cuscutae. These results provide references for further purification of bioactive ingredients from plant extracts by using AB-COP.


Assuntos
Biflavonoides , Selaginellaceae , Poluentes Químicos da Água , Adsorção , Biflavonoides/química , Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , Cinética , Polímeros , Selaginellaceae/química , Espectroscopia de Infravermelho com Transformada de Fourier
4.
J Healthc Eng ; 2022: 1005449, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35251556

RESUMO

Selaginella uncinata shows particularly rare blue leaves. Previous research has shown that structural interference by the cell wall of adaxial epidermal cells imparts blue coloration in leaves of S. uncinata; the objective of this study was to see whether anthocyanins might additionally contribute to this color, as changes in pH, and conjugation with metals and other flavonoids is also known to result in blue coloration in plants. We compared anatomical and biochemical traits of shade-grown (blue) S. uncinata leaves to high light (red) leaves of the same species and also to a non-blue (green) leaves of a congeneric S. kraussiana. By examining the anatomical structure, we found that the shape of adaxial epidermis of S. uncinata leaves was convex or lens-shaped on the lateral view and irregular circles with smooth embossment on the top view. These features were different from those of the abaxial and adaxial epidermis of S. kraussiana. We suspect that these structures increase the proportion of incident light entering the cell, deepening the leaf color, and therefore may be related to blue leaf color in S. uncinata. By examining biochemical traits, we found little difference in leaf pH value among the leaf types; all leaves contained several metal ions such as Mg, Fe, Mn, and copigments such as flavones. However, because there was no anthocyanin in blue S. uncinata leaves, we concluded that blue coloration in S. uncinata leaves is not caused by the three hypotheses of blue coloration: alkalization of the vacuole pH, metal chelation, or copigmentation with anthocyanins, but it may be related to the shape of the leaf adaxial epidermis.


Assuntos
Antocianinas , Selaginellaceae , Antocianinas/metabolismo , Cor , Humanos , Folhas de Planta/metabolismo , Selaginellaceae/metabolismo
5.
Talanta ; 243: 123284, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35255433

RESUMO

Insufficient acetylcholine (ACh) can cause cognitive and memory dysfunction, clinically known as, Alzheimer's disease (AD). Acetylcholinesterase (AChE) can hydrolyze ACh into acetic acid and inactivate choline. Therefore, inhibiting the activity of AChE would help to improve the effectiveness of AD treatment. Currently, the methods for rapid screening of AChE inhibitors are limited. This study reports the application of AChE-immobilized magnetic nanoparticles as a drug screening tool to screen AChE inhibitors for natural products. First, AChE was immobilized on a surface of amino-modified magnetic nanoparticles using covalent binding and the AChE concentration, and the pH as well as time was optimized to obtain the maximum enzyme immobilization yield (61.4 µg/mg), and the kinetic model indicated that AChE-immobilized magnetic nanoparticles and the substrate had the high affinity and specificity. Then, a ligand fishing experiment was carried out using a mixed model of tacrine (an inhibitor of AChE) and caffeic acid (a non-inhibitor of AChE) to verify the specificity of the immobilized AChE, and the conditions for ligand fishing were further optimized. Finally, the optimized immobilized AChE was combined with UPLC-MS to screen for AChE inhibitors in Selaginella doederleinii Hieron extracts. Four compounds were confirmed to be potent AChE inhibitors. Among the four compounds, amentoflavone had a stronger AChE inhibitory effect than tacrine (positive control) with an IC50 of 0.73 ± 0.009 µmol/L. The results showed that AChE-functionalized magnetic nanoparticles can be used in the discovery of target drugs from complex matrices.


Assuntos
Nanopartículas , Selaginellaceae , Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Cromatografia Líquida , Enzimas Imobilizadas/química , Fenômenos Magnéticos , Selaginellaceae/química , Selaginellaceae/metabolismo , Espectrometria de Massas em Tandem
6.
Biomol NMR Assign ; 16(1): 153-158, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35279790

RESUMO

Members of the tristetraprolin (TTP) family of RNA binding proteins (RBPs) regulate the metabolism of a variety of mRNA targets. In mammals, these proteins modulate many physiological processes, including immune cell activation, hematopoiesis, and embryonic development. Regulation of mRNA stability by these proteins requires that the tandem zinc finger (TZF) domain binds initially and directly to target mRNAs, ultimately leading to their deadenylation and decay. Proteins of this type throughout eukarya possess a highly conserved TZF domain, suggesting that they are all capable of high-affinity RNA binding. However, the mechanism of TTP-mediated mRNA decay is largely undefined. Given the vital role that these TTP family proteins play in maintaining RNA homeostasis throughout eukaryotes, we focused here on the first, key step in this process: recognition and binding of the TZF domain to target RNA. For these studies, we chose a primitive plant, the spikemoss Selaginella moellendorffii, which last shared a common ancestor with humans more than a billion years ago. Here we report the near complete backbone and side chain resonance assignments of the spikemoss TZF domain, including: (1) the assignment of the RNA-TZF domain complex, representing one of only two data sets currently available for the entire TTP family of proteins; and (2) the first NMR resonance assignments of the entire TZF domain, in the RNA-free form. This work will serve as the basis for further NMR structural investigations aimed at gaining insights into the process of RNA recognition and the mechanisms of TTP-mediated mRNA decay.


Assuntos
Selaginellaceae , Tristetraprolina , Animais , Família , Humanos , Mamíferos/genética , Mamíferos/metabolismo , Ressonância Magnética Nuclear Biomolecular , RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Selaginellaceae/genética , Selaginellaceae/metabolismo , Tristetraprolina/química , Tristetraprolina/genética , Tristetraprolina/metabolismo , Dedos de Zinco/genética
7.
J Exp Bot ; 73(12): 3898-3912, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35312760

RESUMO

While most plants die below a threshold of water content, desiccation-tolerant species display specific responses that allow them to survive extreme dehydration. Some of these responses are activated at critical stages during water loss and could represent the difference between desiccation tolerance (DT) and death. Here, we report the development of a simple and reproducible system to determine DT in Selaginella species. The system is based on exposure of excised tissue to a dehydration agent inside small containers, and subsequent evaluation for tissue viability. We evaluated several methodologies to determine viability upon desiccation including: triphenyltetrazolium chloride (TTC) staining, the quantum efficiency of PSII, antioxidant potential, and relative electrolyte leakage. Our results show that the TTC test is a simple and accurate assay to identify novel desiccation-tolerant Selaginella species, and can also indicate viability in other desiccation-tolerant models (i.e. ferns and mosses). The system we developed is particularly useful to identify critical points during the dehydration process. We found that a desiccation-sensitive Selaginella species shows a change in viability when dehydrated to 40% relative water content, indicating the onset of a critical condition at this water content. Comparative studies at critical stages could provide a better understanding of DT mechanisms and unravel insights into the key responses to survive desiccation.


Assuntos
Gleiquênias , Selaginellaceae , Biomarcadores , Desidratação , Dessecação , Água/fisiologia
8.
PLoS One ; 17(2): e0263928, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35148336

RESUMO

Transcriptional regulator PEAPOD (PPD) and its binding partners comprise a complex that is conserved throughout many core eudicot plants with regard to protein domain sequence and the function of controlling organ size and shape. Orthologues of PPD also exist in the basal angiosperm Amborella trichopoda, various gymnosperm species, the lycophyte Selaginella moellendorffii and several monocot genera, although until now it was not known if these are functional sequences. Here we report constitutive expression of orthologues from species representing diverse taxa of plant phylogeny in the Arabidopsis Δppd mutant. PPD orthologues from S. moellendorffii, gymnosperm Picea abies, A. trichopoda, monocot Musa acuminata, and dicot Trifolium repens were able to complement the mutant and return it to the wild-type phenotype, demonstrating the conserved functionality of PPD throughout vascular plants. In addition, analysis of bryophyte genomes revealed potential PPD orthologues in model liverwort and moss species, suggesting a more primitive lineage for this conserved regulator. The Poaceae (grasses) lack the genes for the PPD module and the reason for loss of the complex from this economically significant family is unclear, given that grasses were the last of the flowering plants to evolve. Bioinformatic analyses identified putative PPD orthologues in close relatives of the Poaceae, indicating that the explanation for absence of PPD in the grasses may be more complex than previously considered. Understanding the mechanisms which led to loss of PPD from the grasses will provide insight into evolution of the Poaceae.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Ligação a DNA/genética , Selaginellaceae/genética , Fatores de Transcrição/genética , Arabidopsis/genética , Evolução Molecular , Deleção de Genes , Regulação da Expressão Gênica de Plantas , Estrutura Molecular , Tamanho do Órgão , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
9.
Bioorg Chem ; 120: 105638, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35121550

RESUMO

Structural modification of natural products is the effective option to improve their pharmacological effects and drug properties. DLF is a lead compound of antitumor drug, which is a broad-spectrum, low toxic and high-efficient component isolated from Selaginella doederleinii Hieron by our research group. Here, we report the structural modification method of this component, and find that the acetylated product of C4'''- OH (C4'''-acetyl-delicaflavone, 4'''ADLF) has better inhibitory effect on the selected cancer cell lines, including, lung, liver, colon and cervical cancer cell lines. Since the increased water solubility of 4'''ADLF may lead to higher absorption rate and activity, we evaluate the pharmacodynamics in vitro and in vivo, and the pharmacokinetic of 4'''ADLF. It shows that 4'''ADLF inhibit the proliferation and induce cycle arrest in tumor cells, and had better anticancer activity and bioavailability than DLF.


Assuntos
Antineoplásicos , Selaginellaceae , Antineoplásicos/farmacologia , Apoptose , Disponibilidade Biológica , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Simulação de Acoplamento Molecular , Estrutura Molecular , Selaginellaceae/química , Solubilidade , Relação Estrutura-Atividade
10.
Phytochemistry ; 195: 113073, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34974412

RESUMO

Six flavonoids, namely, three undescribed biflavonoids, one undescribed 8-aryl flavonoid, and two known compounds, were isolated from Selaginella tamariscina (P.Beauv.) Spring. The structures and absolute configurations of those undescribed compounds were established by NMR spectroscopy data, HRESIMS analyses and electronic circular dichroism (ECD) analyses. In addition, all the isolates were evaluated for their hypoglycemic activity in HepG2 cells. Involvenflavone H, I, and J significantly increased glucose consumption in both normal and insulin-resistant HepG2 cells. Interestingly, these three compounds can effectively upregulate the protein expression of glucokinase (GCK) and adenylate cyclases (ADCYs). These results suggested that involvenflavone H, I, and J (especially involvenflavone J) may have potent hypoglycemic activity, which also provided promising molecular targets for the treatment of diabetes.


Assuntos
Selaginellaceae , Flavonoides/farmacologia , Hipoglicemiantes/farmacologia , Insulina , Estrutura Molecular
11.
Mol Phylogenet Evol ; 169: 107410, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35031459

RESUMO

As one of the earliest land plant lineages, Selaginella is important for studying land plant evolution. It is the largest genus of lycophytes containing 700-800 species. Some unique characters of Selaginella plastomes have been reported, but based only on 20 species. There have been no plastome phylogenies of Selaginella based on a relatively large sampling, and no efforts have been made to resolve the phylogeny of the enigmatic Sinensis group whose relationships have been unclear based on small datasets. Here we investigated the structures of 59 plastomes representing 51 species covering all six subgenera and 18 sections of Selaginella except two sections and including the intriguing Sinensis group for the first time. Our major results include: (1) the plastome size of Selaginella ranges tremendously from 78,492 bp to 187,632 bp; (2) there are numerous gene losses in Selaginella comparing with other lycophytes, Isoëtaceae and Lycopodiaceae; (3) the gene contents and plastome structures in Selaginella vary lineage-specifically and all infrageneric taxa are well supported in the plastome phylogeny; (4) the ndh gene family tends to lose or pseudogenize in those species with DR structure and without other short or medium repeats; (5) the short and medium repeat regions in SC mediate many conformations causing diverse and complex plastome structures, and six new conformations are discovered; (6) forty-eight species sampled have high GC content (>50%) but three species in the Sinensis group have âˆ¼ 30% GC content in plastomes, similar to most vascular plants; (7) the Sinensis group is monophyletic, includes at least two subgroups, and has the smallest plastomes in land plants except some parasitic plants, and their plastomes do not contain any tRNAs; (8) the younger lineages in Selaginella tend to have higher GC content, whereas the older lineages tend to have lower GC content; and (9) because of incomplete genomic data and abnormal structures or some unknown reasons, even the concatenated plastomes could not well resolve the phylogenetic relationships in Selaginella with confidence, highlighting the difficulty in resolving the phylogeny and evolution of this particularly important land plant lineage.


Assuntos
Genomas de Plastídeos , Selaginellaceae , Composição de Bases , Evolução Molecular , Filogenia , Selaginellaceae/genética
12.
Plant Sci ; 315: 111129, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35067299

RESUMO

Abiotic stresses have the greatest impact on the growth and productivity of crops, especially under current and future extreme weather events due to climate change. Thus, it is vital to explore novel strategies to improve crop plant abiotic stress tolerance to feed an ever-growing world population. Selaginella lepidophylla is a desiccation-tolerant spike moss with specialized adaptations that allow it to tolerate water loss down to 4% relative water content. A candidate basic helix-loop-helix (bHLH) transcription factor was highly expressed at 4% relative water content in S. lepidophylla (SlbHLH). This SlbHLH gene was codon-optimized (SlbHLHopt) and overexpressed in Arabidopsis for functional characterization. Overexpression of the SlbHLHopt gene not only significantly increased plant growth, development, and integrated water-use efficiency, but also significantly increased seed germination and green cotyledon emergence rates under water-deficit stress and salt stress conditions. Under a 150 mM NaCl salt stress condition, SlbHLHopt-overexpressing lines increased primary root length, the number of lateral roots, and fresh and dry biomass at the seedling stage compared to control lines. Interestingly, SlbHLHopt-overexpressing lines also have significantly higher flavonoid content. Altogether, these results suggest that SlbHLH functions as an important regulator of plant growth, development, abiotic stress tolerance, and water-use efficiency.


Assuntos
Adaptação Fisiológica/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Plantas Geneticamente Modificadas/fisiologia , Selaginellaceae/genética , Água/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Filogenia , Melhoramento Vegetal , Transformação Genética
13.
Bioorg Med Chem Lett ; 56: 128486, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34875389

RESUMO

A new biflavonoid, (2''S)-6''-methyl-2'',3''-dihydroochnaflavone (1), along with two known ochnaflavones (2, 3), four known amentoflavones (4-7) and two known robustaflavones (8, 9) were obtained from the 70% EtOH extract of Selaginella trichoclada. The chemical structures of isolated compounds were elucidated by extensive spectroscopic analyses. Overall, compounds 1-9 displayed moderate cytotoxic effects against human breast cancer MCF-7 cell lines. Among them, compounds 2 and 8 exhibited relatively strong cytotoxic effects against MCF-7 cells with an IC50 value of 7.7 and 6.9 µΜ, respectively. The results of RNA-sequencing and KEGG functional enrichment analysis showed that 8 could induce ferroptosis in MCF-7 cells by down-regulating the expression of ferroptosis-related genes including ACSL4, NOXO1, NOXA1, ACSL5, STEAP3, LPCAT3, ATG7 and TP53. Then 8 could inhibit the expression of ACSL4 proteins through molecule docking analysis, which showed a strong interaction of - 11.89 Kcal/mol binding energy. Those results indicate that 8 could be chemotherapy agents to fight drug resistance in breast cancer by down-regulating the expression level of ACSL4 proteins via ferroptosis, which needs to be further certified in vitro.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Biflavonoides/farmacologia , Extratos Vegetais/farmacologia , Selaginellaceae/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Biflavonoides/química , Biflavonoides/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7 , Simulação de Dinâmica Molecular , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade
14.
Phytochemistry ; 195: 113051, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34890887

RESUMO

Nonclassical P450s of the CYP74 family catalyse the secondary conversions of fatty acid hydroperoxides to bioactive oxylipins in plants. The model organism, spikemoss Selaginella moellendorffii Hieron, possesses at least ten CYP74 genes of novel J, K, L, and M subfamilies. The cloning of three CYP74L genes and catalytic properties of recombinant proteins are described in the present work. The CYP74L1 possessed mainly hydroperoxide lyase (HPL) activity towards the 13(S)-hydroperoxide of α-linolenic acids (13-HPOT) and nearly equal HPL and allene oxide synthase (AOS) activities towards the 13(S)-hydroperoxide of linoleic acids (13-HPOD). The 9-hydroperoxides were poor substrates for CYP74L1 and led to the production of mainly the α-ketols (AOS products) and minorities of HPL and epoxyalcohol synthase (EAS) products. The CYP74L2 possessed the AOS activity towards all tested hydroperoxides. CYP74L3 possessed low HPL/EAS activity. Besides, the aerial parts of S. moellendorffii plants possessed complex oxylipins patterns including divinyl ethers, epoxyalcohols, and 12-oxo-phytodienoic acid. Characterization of the CYP74L enzymes and oxylipin pattern updates the knowledge on the complex oxylipin biosynthetic machinery in the surviving oldest taxa of vascular plants.


Assuntos
Selaginellaceae , Aldeído Liases , Sequência de Aminoácidos , Sistema Enzimático do Citocromo P-450 , Oxirredutases Intramoleculares , Oxilipinas , Proteínas de Plantas/metabolismo , Selaginellaceae/metabolismo
15.
Physiol Plant ; 174(1): e13604, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34811759

RESUMO

The Lycophyte Selaginella martensii efficiently acclimates to diverse light environments, from deep shade to full sunlight. The plant does not modulate the abundance of the Light Harvesting Complex II, mostly found as a free trimer, and does not alter the maximum capacity of thermal dissipation (NPQ). Nevertheless, the photoprotection is expected to be modulatable upon long-term light acclimation to preserve the photosystems (PSII, PSI). The effects of long-term light acclimation on PSII photoprotection were investigated using the chlorophyll fluorometric method known as "photochemical quenching measured in the dark" (qPd ). Singularly high-qPd values at relatively low irradiance suggest a heterogeneous antenna system (PSII antenna uncoupling). The extent of antenna uncoupling largely depends on the light regime, reaching the highest value in sun-acclimated plants. In parallel, the photoprotective NPQ (pNPQ) increased from deep-shade to high-light grown plants. It is proposed that the differences in the long-term modulation in the photoprotective capacity are proportional to the amount of uncoupled LHCII. In deep-shade plants, the inconsistency between invariable maximum NPQ and lower pNPQ is attributed to the thermal dissipation occurring in the PSII core.


Assuntos
Arabidopsis , Selaginellaceae , Arabidopsis/metabolismo , Clorofila , Luz , Complexos de Proteínas Captadores de Luz/metabolismo , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , Selaginellaceae/metabolismo
16.
J Ethnopharmacol ; 286: 114836, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-34793885

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Previously, the total bioflavonoids extract from Selaginella doederleinii (SDTBE) presented favorable in vitro and in vivo activities against non-small cell lung cancer (NSCLC), hinting at its medicinal potential. However, up to nowadays, targets and integrative action mechanisms of SDTBE are still not very clear, which presents an obstacle to the development of herbal medicine. AIM OF THE STUDY: The present study aimed to disclose the potential targets and integrative action mechanism of SDTBE against NSCLC. MATERIALS AND METHODS: A system pharmacology-based strategy including target fishing, network pharmacology analysis and molecular docking were applied to predict the potential targets and pathways for the seven main active ingredients in SDTBE. A proteomics study was subsequently performed for validating the affected pathways and possible targets. Western blot assay, mouse xenograft tumor model and immunofluorescence assays were used to further confirm the key targets and integrative action mechanisms of SDTBE against NSCLC. RESULTS: By system pharmacology, it was inferred that SDTBE could mainly act on mitogen-activated protein kinase (MAPK) and PI3K-AKT signaling pathways by targeting epidermal growth factor receptor (EGFR), protein kinase B (AKT) and mitogen-activated or extracellular signal-regulated protein kinase (MEK), which was validated by proteomics results, and further confirmed in vitro and in vivo by Western blot and immunofluorescence assays. CONCLUSION: SDTBE targeting multi-targets including EGFR, AKT and MEK could exert its anti-NSCLC effect mainly via MAPK and PI3K-AKT signaling pathways.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Flavonoides/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Selaginellaceae/química , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Flavonoides/isolamento & purificação , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinase/metabolismo , Proteômica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Nat Prod Res ; 36(7): 1797-1802, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32924604

RESUMO

A chalcone-flavonone type biflavonoid, trichocladabiflavone A (1), along with eight known biflavonoids (2-9) were isolated from the 70% EtOH extract of Selaginella trichoclada. Their structures were elucidated by extensive spectroscopic analyses. Compound 1 was the first chalcone-flavonone type biflavonoid reported in the genus Selaginella. Moreover, compound 1 exhibited moderate cytotoxicity against DU145, MCF-7 and PC3 human cancer cell lines.


Assuntos
Biflavonoides , Chalcona , Chalconas , Selaginellaceae , Biflavonoides/química , Biflavonoides/farmacologia , Chalcona/química , Humanos , Estrutura Molecular , Extratos Vegetais/química , Selaginellaceae/química
18.
Nat Prod Res ; 36(1): 279-286, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32571087

RESUMO

Two new nor-lignans, pulvin A (1) and moellenoside C (2), along with two known compounds (3-4) were isolated from the whole plant of Selaginella pulvinate (Hook. & Grev.) Maxim. The structures of the new compounds were established on the basis of spectroscopic data and acid hydrolysis. All the isolates were investigated for their antihyperglycemic activities in 3T3-L1 adipocytes. The results showed that compounds 1 and 2 promoted the glucose consumption prominently in 3T3-L1 adipocytes in a dose-response manner. Compound 1 and 2 induced 1.14-1.73 folds and 1.03-1.55 folds changes relative to the basal level, respectively, in the concentration range of 12.5 µM to 50 µM.


Assuntos
Lignanas , Selaginellaceae , Células 3T3-L1 , Animais , Hipoglicemiantes/farmacologia , Camundongos , Estrutura Molecular
19.
Parasitol Int ; 86: 102458, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34509671

RESUMO

Leishmaniasis chemotherapy is a bottleneck in disease treatment. Although available, chemotherapy is limited, toxic, painful, and does not lead to parasite clearance, with parasite resistance also being reported. Therefore, new therapeutic options are being investigated, such as plant-derived anti-parasitic compounds. Amentoflavone is the most common biflavonoid in the Selaginella genus, and its antileishmanial activity has already been described on Leishmania amazonensis intracellular amastigotes but its direct action on the parasite is controversial. In this work we demonstrate that amentoflavone is active on L. amazonensis promastigotes (IC50 = 28.5 ± 2.0 µM) and amastigotes. Transmission electron microscopy of amentoflavone-treated promastigotes showed myelin-like figures, autophagosomes as well as enlarged mitochondria. Treated parasites also presented multiple lipid droplets and altered basal body organization. Similarly, intracellular amastigotes presented swollen mitochondria, membrane fragments in the lumen of the flagellar pocket as well as autophagic vacuoles. Flow cytometric analysis after TMRE staining showed that amentoflavone strongly decreased mitochondrial membrane potential. In silico analysis shows that amentoflavone physic-chemical, drug-likeness and bioavailability characteristics suggest it might be suitable for oral administration. We concluded that amentoflavone presents a direct effect on L. amazonensis parasites, causing mitochondrial dysfunction and parasite killing. Therefore, all results point for the potential of amentoflavone as a promising candidate for conducting advanced studies for the development of drugs against leishmaniasis.


Assuntos
Biflavonoides/farmacologia , Leishmania mexicana/fisiologia , Mitocôndrias/fisiologia , Selaginellaceae/química , Biflavonoides/química , Leishmania mexicana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Tripanossomicidas
20.
Int J Mol Sci ; 22(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34884882

RESUMO

Cytokinins (CKs) control many plant developmental processes and responses to environmental cues. Although the CK signaling is well understood, we are only beginning to decipher its evolution. Here, we investigated the CK perception apparatus in early-divergent plant species such as bryophyte Physcomitrium patens, lycophyte Selaginella moellendorffii, and gymnosperm Picea abies. Of the eight CHASE-domain containing histidine kinases (CHKs) examined, two CHKs, PpCHK3 and PpCHK4, did not bind CKs. All other CHK receptors showed high-affinity CK binding (KD of nM range), with a strong preference for isopentenyladenine over other CK nucleobases in the moss and for trans-zeatin over cis-zeatin in the gymnosperm. The pH dependences of CK binding for these six CHKs showed a wide range, which may indicate different subcellular localization of these receptors at either the plasma- or endoplasmic reticulum membrane. Thus, the properties of the whole CK perception apparatuses in early-divergent lineages were demonstrated. Data show that during land plant evolution there was a diversification of the ligand specificity of various CHKs, in particular, the rise in preference for trans-zeatin over cis-zeatin, which indicates a steadily increasing specialization of receptors to various CKs. Finally, this distinct preference of individual receptors to different CK versions culminated in vascular plants, especially angiosperms.


Assuntos
Citocininas/metabolismo , Embriófitas/metabolismo , Histidina Quinase/metabolismo , Isopenteniladenosina/metabolismo , Bryopsida/metabolismo , Biologia Computacional , Concentração de Íons de Hidrogênio , Picea/metabolismo , Proteínas de Plantas/metabolismo , Selaginellaceae/metabolismo , Especificidade por Substrato
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