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1.
Nutrients ; 16(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38201838

RESUMO

In an era of increasing interest in the potential health benefits of medicinal foods, the need to assess their safety and potential toxicity remains a critical concern. While these natural remedies have garnered substantial attention for their therapeutic potential, a comprehensive understanding of their effects on living organisms is essential. We examined 316 herbal extracts to determine their potential nematocidal attributes in Caenorhabditis elegans. Approximately 16% of these extracts exhibited the capacity to induce diminished survival rates and larval arrest, establishing a correlation between larval arrest and overall worm viability. Certain extracts led to an unexpected increase in male nematodes, accompanied by a discernible reduction in DAPI-stained bivalent structures and perturbed meiotic advancement, thereby disrupting the conventional developmental processes. Notably, Onobrychis cornuta and Veratrum lobelianum extracts activated a DNA damage checkpoint response via the ATM/ATR and CHK-1 pathways, thus hindering germline development. Our LC-MS analysis revealed jervine in V. lobelianum and nine antitumor compounds in O. cornuta. Interestingly, linoleic acid replicated phenotypes induced by O. cornuta exposure, including an increased level of pCHK-1 foci, apoptosis, and the MAPK pathway. Mutants in the MAPK pathway mitigated the decline in worm survival, underscoring its importance in promoting worm viability. This study reveals complex interactions between herbal extracts and C. elegans processes, shedding light on potential antitumor effects and mechanisms. The findings provide insights into the complex landscape of herbal medicine's impact on a model organism, offering implications for broader applications.


Assuntos
Fabaceae , Veratrum , Masculino , Animais , Caenorhabditis elegans , Antinematódeos , Células Germinativas
2.
Phytochemistry ; 185: 112703, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33639582

RESUMO

A phytochemical investigation of the roots of Xerophyllum tenax led to the isolation of three undescribed feruloyl sucrose derivatives along with two known feruloyl sucrose derivatives, heloniosides A and B. This is the first report of their occurrence in the genus Xerophyllum and the family Melanthiaceae. The structures of these compounds were elucidated on the basis of chemical and spectroscopic analysis including 1D and 2D NMR and analysis of MS-MS fragmentation.


Assuntos
Melanthiaceae , Sacarose , Estrutura Molecular , Extratos Vegetais , Raízes de Plantas
3.
Biochem Biophys Res Commun ; 516(3): 733-738, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31255282

RESUMO

Neuroblastoma (NB) is a neuroendocrine tumor derived from neural crest cells. Approximately 90% of cases occur in children less than 5 years old. The amplification of MYCN correlates with high-risk neuroblastoma and patients with MYCN amplified showed poorer prognosis than those without MYCN amplification. In this study, three compounds isolated from Juniperus oblonga showed anti-proliferative activity against NB cell lines with and without tetracycline inducible MYCN over-expression which were identified as (-)-deoxypodophyllotoxin (1), (-)-matairesinol (2) and (+)-isocupressic acid (3). The effects of compounds 2 and 3 in NB cells included a decrease in NB cell viability and induction of apoptosis. Compound 1 was more effective in NB cells over-expressing MycN. Compound 1 also showed almost 2-fold induction of intracellular free calcium levels in M2(+) cells, which may indicate a different mechanism of action for this compound. Cytotoxicity studies against the human embryonic kidney cell (HEK-293) showed compounds 1, 2 and 3 were ineffective in the non-cancer cells at concentrations approximating their IC50 against the NB cell lines. These results may lead to safer and more effective treatment options for NB patients especially for those with high-risk NB.


Assuntos
Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Juniperus/química , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Extratos Vegetais/farmacologia , Antineoplásicos/química , Ácidos Carboxílicos/química , Ácidos Carboxílicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Pré-Escolar , Diterpenos/química , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas , Furanos/química , Furanos/farmacologia , Células HEK293 , Humanos , Concentração Inibidora 50 , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Fitoterapia/métodos , Extratos Vegetais/química , Podofilotoxina/análogos & derivados , Podofilotoxina/química , Podofilotoxina/farmacologia , Tetra-Hidronaftalenos/química , Tetra-Hidronaftalenos/farmacologia
4.
J Nat Prod ; 82(4): 832-839, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30892891

RESUMO

Organic anion transporters 1 (OAT1) and 3 (OAT3) play important roles in the renal elimination of a range of substrate molecules. Little is known about natural products that can modulate OAT1 and OAT3 activities. The medullae of Juncus effusus is often used for the treatment of dysuria in traditional Chinese medicine. To study the interactions of phytochemicals in J. effusus with human OAT1 and OAT3, a bioactivity guided phytochemical investigation led to seven new phenanthrenoids along with nine known compounds, including eight phenanthrenoids and a benzophenone from the dichloromethane soluble fraction of a methanol extract of the medullae of J. effusus. The structures were established by physical data analysis, including high-resolution electrospray ionization mass spectrometry and 1D and 2D NMR. The compounds were evaluated for inhibition of OAT1 and OAT3 in vitro. Compounds 10 and 16 were inhibitors for OAT1, and compounds 1-3, 10, and 16 were inhibitors for OAT3 with IC50 values less than 5.0 µM. Dihydrophenanthrene 1 markedly altered the pharmacokinetic parameters of the diuretic drug furosemide, a known substrate of both OAT1 and OAT3, in vivo.


Assuntos
Transportadores de Ânions Orgânicos Sódio-Independentes/antagonistas & inibidores , Fenantrenos/farmacologia , Animais , Células HEK293 , Humanos , Masculino , Fenantrenos/química , Espectroscopia de Prótons por Ressonância Magnética , Ratos , Ratos Wistar , Análise Espectral/métodos , Relação Estrutura-Atividade
5.
Biochem Biophys Res Commun ; 509(4): 931-936, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30648554

RESUMO

Organic anion transporters (OATs in humans, Oats in rodents) play an important role in the distribution and excretion of numerous endogenous metabolic products and exogenous organic anions, including a host of widely prescribed drugs. Their ligand recognition is also important for drug therapy and development. In this study, the n-butanol and dichloromethane soluble fractions of Juniperus oblonga were found to inhibit OAT3 in vitro and three biflavonoids were found to be responsible for this activity. One of these compounds, amentoflavone exhibited stronger inhibition than probenecid, a known strong inhibitor of OAT3. Biological characterization of amentoflavone in vivo also showed inhibition of Oat3. Preliminary observations of structure-activity relationships suggest that the biflavonoids are more potent inhibitors of this transporter than their corresponding monomer, and that methylation of even a single hydroxyl group results in a substantial decrease in activity. This greater potency of the biflavonoids may indicate the need for a more in-depth investigation of the distribution of biflavonoids in plants used as foodstuffs and herbal medicines, due to their potential for causing interactions with OAT3 substrate drugs.


Assuntos
Biflavonoides/farmacologia , Juniperus/química , Transportadores de Ânions Orgânicos Sódio-Independentes/antagonistas & inibidores , Animais , Biflavonoides/isolamento & purificação , Dimerização , Interações Medicamentosas , Humanos , Extratos Vegetais/farmacologia , Probenecid/farmacologia
6.
Planta Med ; 85(3): 225-230, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30248705

RESUMO

Phytochemical investigation of Camphorosma lessingii has resulted in the isolation of four previously unreported isoflavones (1: -4: ) and eight known compounds (5: -12: ). Nine of these compounds (1: -6, 8: -10: ) are reported for the first time from members of the family Amaranthaceae. The structures of all isolated compounds were determined by spectroscopic methods, primarily one-dimensional and two-dimensional nuclear magnetic resonance and mass spectrometry. The absolute configuration of 6: was confirmed by circular dichroism. Inhibition of the organic anion transporters, OAT1 and OAT3, by the isolated compounds was evaluated. Among them, 7, 2'-dihydroxy- 6,8-dimethoxyisoflavone (1: ), 2'-hydroxy-6,7,8-trimethoxyisoflavone (2: ), 6,2'-dihydroxy-7,8-dimethoxyisoflavone (3: ), and 7-methoxyflavone (5: ) showed a significant inhibitory effect on 6-carboxyfluorescein uptake mediated by OAT1 and OAT3.


Assuntos
Chenopodiaceae/química , Isoflavonas/farmacologia , Proteína 1 Transportadora de Ânions Orgânicos/antagonistas & inibidores , Transportadores de Ânions Orgânicos Sódio-Independentes/antagonistas & inibidores , Dicroísmo Circular , Células HEK293 , Humanos , Isoflavonas/química , Isoflavonas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
7.
PeerJ ; 5: e3333, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28560096

RESUMO

BACKGROUND: Herb-drug interactions (HDIs) resulting from concomitant use of herbal products with clinical drugs may cause adverse reactions. Organic anion transporter 1 (OAT1) and 3 (OAT3) are highly expressed in the kidney and play a key role in the renal elimination of substrate drugs. So far, little is known about the herbal extracts that could modulate OAT1 and OAT3 activities. METHODS: HEK293 cells stably expressing human OAT1 (HEK-OAT1) and OAT3 (HEK-OAT3) were established and characterized. One hundred seventy-two extracts from 37 medicinal and economic plants were prepared. An initial concentration of 5 µg/ml for each extract was used to evaluate their effects on 6-carboxylfluorescein (6-CF) uptake in HEK-OAT1 and HEK-OAT3 cells. Concentration-dependent inhibition studies were conducted for those extracts with more than 50% inhibition to OAT1 and OAT3. The extract of Juncus effusus, a well-known traditional Chinese medicine, was assessed for its effect on the in vivo pharmacokinetic parameters of furosemide, a diuretic drug which is a known substrate of both OAT1 and OAT3. RESULTS: More than 30% of the plant extracts at the concentration of 5 µg/ml showed strong inhibitory effect on the 6-CF uptake mediated by OAT1 (61 extracts) and OAT3 (55 extracts). Among them, three extracts for OAT1 and fourteen extracts for OAT3 were identified as strong inhibitors with IC50 values being <5 µg/ml. Juncus effusus showed a strong inhibition to OAT3 in vitro, and markedly altered the in vivo pharmacokinetic parameters of furosemide in rats. CONCLUSION: The present study identified the potential interactions of medicinal and economic plants with human OAT1 and OAT3, which is helpful to predict and to avoid potential OAT1- and OAT3-mediated HDIs.

8.
Int J Oncol ; 48(4): 1608-16, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26848085

RESUMO

Effective neuroblastoma (NB) treatments are still limited despite treatment options available today. Therefore, this study attempted to identify novel plant extracts that have anticancer effects. Cytotoxicity and increased intracellular calcium levels were determined using the Sulforhodamine B (SRB) assay and Fluo4-AM (acetoxymethyl) staining and fluorescence microscopy in NB cells in order to screen a library of plant extracts. The current study examined the anticancer effects of a dichloromethane extract from Scrophularia orientalis L. (Scrophulariaceae), a plant that has been used in Traditional Chinese Medicine. This extract contained highly potent agents that significantly reduced cell survival and increased calcium levels in NB cells. Further analysis revealed that cell death induced by this extract was associated with intracellular calcium release, opening of the MPTP, caspase 3- and PARP-cleavage suggesting that this extract induced aberrant calcium signaling that resulted in apoptosis via the mitochondrial pathway. Therefore, agents from Scrophularia orientalis may have the potential to lead to new chemo-therapeutic anticancer drugs. Furthermore, targeting intracellular calcium signaling may be a novel strategy to develop more effective treatments for NB.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Neuroblastoma/metabolismo , Extratos Vegetais/farmacologia , Scrophularia/química , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Neuroblastoma/tratamento farmacológico
9.
Nat Prod Commun ; 10(6): 925-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26197518

RESUMO

Metrosideros polymorpha is a highly variable and widely-distributed tree native to the Hawaiian islands. We describe here the isolation of two new gossypetin derivatives and three new C-methylated flavonol glycosides, which are highly uncommon and may prove to be useful chemotaxonomic markers for the species. In addition, a wide range of known flavonoid glycosides, chalcones, and terpenoids were isolated alongside the new compounds.


Assuntos
Flavonóis/química , Glicosídeos/química , Myrtaceae/química , Extratos Vegetais/química , Árvores/química , Flavonóis/isolamento & purificação , Glicosídeos/isolamento & purificação , Havaí , Extratos Vegetais/isolamento & purificação
10.
J Agric Food Chem ; 62(46): 11323-34, 2014 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-25376013

RESUMO

Thirty-six anthurium varieties, sampled from species and commercial cultivars, were extracted and profiled by liquid-chromatography-mass spectrometry (HPLC-MS). Three hundred fifteen compounds, including anthocyanins, flavonoid glycosides, and other phenolics, were detected from these extracts and used in chemotaxonomic analysis of the specimens. Hierarchical cluster analysis (HCA) revealed close chemical similarities between all the commercial standard cultivars, while tulip-shaped cultivars and species displayed much greater chemical variation. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) supported the results from HCA and were used to identify key metabolites characteristic of standard and tulip cultivars and to identify chemical markers indicative of a particular ancestry. Discriminating metabolites included embinin, 4, which was characteristic of standard-shaped spathes and indicated ancestry from Anthurium andraeanum, while isocytisoside 7-glucoside, 7, was found in the majority of tulip-shaped cultivars and suggested that Anthurium amnicola or Anthurium antioquiense had contributed to their pedigree.


Assuntos
Araceae/química , Fenóis/química , Extratos Vegetais/química , Araceae/crescimento & desenvolvimento , Araceae/metabolismo , Análise Discriminante , Havaí , Análise Multivariada , Fenóis/metabolismo , Extratos Vegetais/metabolismo
11.
Bioorg Med Chem Lett ; 22(17): 5559-62, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22850207

RESUMO

Bioassay-guided fractionation of the hexane extract from the flowers of Vernonia cinerea (Asteraceae) led to the isolation of a new sesquiterpene lactone, 8α-hydroxyhirsutinolide (2), and a new naturally occurring derivative, 8α-hydroxyl-1-O-methylhirsutinolide (3), along with seven known compounds (1 and 4-9). The structures of the new compounds were determined by 1D and 2D NMR experiments and by comparison with the structure of compound 1, whose relative stereochemistry was determined by X-ray analysis. The isolated compounds were evaluated for their cancer chemopreventive potential based on their ability to inhibit nitric oxide (NO) production and tumor necrosis factor alpha (TNF-α)-induced NF-κB activity. Compounds 1, 2, 4, 5, and 9 inhibited TNF-α-induced NF-κB activity with IC(50) values of 3.1, 1.9, 0.6, 5.2, and 1.6 µM, respectively; compounds 4 and 6-9 exhibited significant NO inhibitory activity with IC(50) values of 2.0, 1.5, 1.2, 2.7, and 2.4 µM, respectively.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Lactonas/química , Lactonas/farmacologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Vernonia/química , Animais , Anti-Inflamatórios/isolamento & purificação , Linhagem Celular , Cristalografia por Raios X , Flores/química , Humanos , Lactonas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Camundongos , Modelos Moleculares , NF-kappa B/imunologia , Neoplasias/prevenção & controle , Óxido Nítrico/antagonistas & inibidores , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Sesquiterpenos/isolamento & purificação , Fator de Necrose Tumoral alfa/imunologia
12.
Nat Prod Commun ; 7(6): 747-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22816298

RESUMO

We describe here the isolation of three flavone 6-C-glycosides from the leaves of Anthurium andraeanum, The two new flavones were identified through detailed spectroscopic analysis as 4"'-(3,4-dimethoxycinnamoyl)-embinin (2) and 4"'-ferruloyl-embinin (3).


Assuntos
Araceae/química , Flavonas/química , Glicosídeos/química , Estrutura Molecular , Folhas de Planta/química
13.
J Nat Prod ; 68(8): 1247-52, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16124770

RESUMO

It has been demonstrated that liver X receptors (LXR) play a significant role in cholesterol homeostasis. Agonists of LXR are expected to increase cellular cholesterol efflux, lower LDL, and raise HDL levels. Screening of a natural product library of plant extracts using a LXR-SPA binding assay and bioassay-guided fractionation of a number of plant and marine gorgonian extracts led to the isolation of a number of active compounds. These included acanthoic acid (1) and alcohol (2), viperidone (3), polycarpol (4), rosacea acid (5), a cycloartane derivative (6), a new cycloartane analogue (7), betulinic acid (8), and gorgostane derivatives (9, 10, and 11). Of these compounds, 1, 4, and 11 exhibited potent binding affinity for alpha-receptor with IC(50) values of 0.25, 0.12, and 0.07 microM, respectively. Functionally they also showed strong coactivator association stimulation for LXRalpha receptor with EC50 values of 0.18, 0.03, and 0.05 microM, respectively. They also exhibited 15-, 8-, and 13-fold induction of the alpha-receptor in a transactivation assay in HEK-293 cells, respectively. In general these compounds were selective for the LXR alpha-receptor over the beta-receptor in all assays and were much better stimulators of the alpha-receptor than the endogenous steroid ligands.


Assuntos
Proteínas de Ligação a DNA/agonistas , Diterpenos/isolamento & purificação , Plantas Medicinais/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Receptores Citoplasmáticos e Nucleares/agonistas , Esteroides/isolamento & purificação , Triterpenos/isolamento & purificação , Animais , Annonaceae/química , Antozoários/química , Bahamas , Cactaceae/química , Campanulaceae/química , Células Cultivadas , Costa Rica , Diterpenos/química , Diterpenos/farmacologia , Guiana , Humanos , Concentração Inibidora 50 , Receptores X do Fígado , Estrutura Molecular , Olacaceae/química , Receptores Nucleares Órfãos , Triterpenos Pentacíclicos , Peru , Pinaceae/química , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Esteroides/química , Esteroides/farmacologia , Triterpenos/química , Triterpenos/farmacologia , Estados Unidos , Ácido Betulínico
14.
J Nat Prod ; 68(4): 617-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15844964

RESUMO

Liver X receptors (LXR) have been implicated in cholesterol homeostasis. Agonists of LXR are expected to increase cholesterol efflux, lower LDL, and raise HDL levels. Screening of a natural product library of plant extracts using a LXR-SPA binding assay and bioassay-guided fractionation of the bark and stem extract of Garcinia humilis led to the discovery of a new polyisoprenylated benzophenone named guttiferone I (1). The IC(50) value for this compound in the LXRalpha-SPA binding assay was 3.4 muM. Details of the isolation, structure elucidation, and ligand binding activity of 1 are described.


Assuntos
Benzofenonas/isolamento & purificação , Proteínas de Ligação a DNA/metabolismo , Garcinia/química , Receptores Citoplasmáticos e Nucleares/metabolismo , Benzofenonas/química , Benzofenonas/farmacologia , Concentração Inibidora 50 , Ligantes , Fígado/metabolismo , Receptores X do Fígado , Estrutura Molecular , Receptores Nucleares Órfãos
15.
J Nat Prod ; 67(2): 228-31, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14987064

RESUMO

Four new congeners, rediocides B-E (2-5), of the previously reported rediocide A (1) were isolated from a methanol extract of the roots of the plant Trigonostemon reidioides. The structures of these minor analogues were elucidated by comparison of their NMR and mass spectral data with those of rediocide A and confirmed by extensive 2D NMR spectral analysis. They all possess potent activity against fleas (Ctenocephalides felis) in an artificial membrane feeding system and exhibited LD(90) values ranging from 0.25 to 0.5 ppm.


Assuntos
Diterpenos/isolamento & purificação , Euphorbiaceae/química , Inseticidas/isolamento & purificação , Plantas Medicinais/química , Sifonápteros , Animais , Culicidae , Diterpenos/química , Diterpenos/farmacologia , Inseticidas/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Macrolídeos , Membranas Artificiais , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Estereoisomerismo , Tailândia
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