Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.914
Filtrar
1.
Angew Chem Int Ed Engl ; 63(16): e202319624, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38376063

RESUMO

9,10-Secosteroids are an important group of marine steroids with diverse biological activities. Herein, we report a chemoenzymatic strategy for the concise, modular, and scalable synthesis of ten naturally occurring 9,10-secosteroids from readily available steroids in three to eight steps. The key feature lies in utilizing a Rieske oxygenase-like 3-ketosteroid 9α-hydroxylase (KSH) as the biocatalyst to achieve efficient C9-C10 bond cleavage and A-ring aromatization of tetracyclic steroids through 9α-hydroxylation and fragmentation. With synthesized 9,10-secosteroides, structure-activity relationship was evaluated based on bioassays in terms of previously unexplored anti-infective activity. This study provides experimental evidence to support the hypothesis that the biosynthetic pathway through which 9,10-secosteroids are formed in nature shares a similar 9α-hydroxylation and fragmentation cascade. In addition to the development of a biomimetic approach for 9,10-secosteroid synthesis, this study highlights the great potential of chemoenzymatic strategies in chemical synthesis.


Assuntos
Secoesteroides , Hidroxilação , Proteínas de Bactérias/metabolismo , Esteroides/química , Oxigenases de Função Mista/metabolismo
2.
Chem Biodivers ; 21(4): e202301993, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342755

RESUMO

A new alkaloids, aplysingoniopora A (1), and new configuration pregnane type steroid compound, 9,17-α-pregn-1,4,20-en-3-one (2), and two known pregnane type steroid compounds (3 and 4) were isolated from hydranth of Goniopora columna corals. The compounds structures and absolute configurations were determined by extensive spectroscopic analysis, MS data, single-crystal X-ray diffraction analysis and quantum chemical calculation. The anticancer effect of the compounds were explored in human non-small-cell lung cancer (NSCLC) A549 cell lines. As the results, the compound 3 and 4 induces toxicity and has proliferation inhibitory effects on A549 cells (IC50=58.99 µM and 58.77 µM, respectively) in vitro.


Assuntos
Alcaloides , Antozoários , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Alcaloides/farmacologia , Alcaloides/química , Esteroides/farmacologia , Esteroides/química , Pregnanos/farmacologia , Estrutura Molecular
3.
Phytochemistry ; 221: 114039, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38417722

RESUMO

Steroids are farnesyl diphosphate-derived triterpene derivatives widely distributed in Meliaceae plants that can have several health benefits due to their biological activities. This literature survey on chemical and pharmacological studies of steroids from the Meliaceae plants indicates that 157 distinct steroids classified into six subclasses including (in decreasing number): pregnane-, stigmastane-, ergostane-, cholestane-, androstane- and ecdysterone-type steroids have been reported from a total of 49 plant species. This review aims to provide a reference document compiling information about the occurrence, chemistry and biological activities of meliaceous steroids for the period from 1988 to July 2023. In particular, generalities about the chemistry of steroids with unusual skeletons and underlying biosynthetic pathways are highlighted. In addition, some structural relationships between different compound types and their biological activities are presented. The information used during the writing of this paper was collected from the online libraries PubMed, Google Scholar and Scifinder using the keywords steroids and Meliaceae with no language restriction. This review points out new avenues for further investigations of steroids from plants of the Meliaceae family.


Assuntos
Meliaceae , Meliaceae/química , Esteroides/farmacologia , Esteroides/química , Pregnanos/química , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia
4.
Phytochemistry ; 220: 114018, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342288

RESUMO

Steroidal alkaloids are the main bioactive components of the bulbs of Fritillaria, which have been used as traditional Chinese medicine, known as "Beimu", for the treatment of cough for thousands of years in China. Cough and dyspnea are the most common symptoms observed in patients with pulmonary fibrosis. However, the antifibrotic activity of steroidal alkaloids has not been reported yet. In this study, two previously unreported cevanine-type steroidal alkaloids (1 and 2), four previously undescribed cevanine-type alkaloid glycosides (3-6), and 19 known steroidal alkaloids (7-25) were isolated from the bulbs of Fritillaria unibracteata var. wabuensis. The structures of these compounds were elucidated by comprehensive HRESIMS and NMR spectroscopic data analysis, as well as DP4+ NMR calculations. The biological evaluation showed that compounds 2, 7-10, 14, 15, and 17 downregulated fibrotic markers induced by transforming growth factor-ß (TGF-ß) in MRC-5 cells. Moreover, compounds 14 and 17 dose dependently inhibited TGF-ß-induced epithelial-mesenchymal transition in A549 cells, alleviated TGF-ß-induced migration and proliferation of fibroblasts, and decreased the expression of fibrotic markers, fibronectin, and N-cadherin in TGF-ß-induced MRC-5 cells. The research showed the potential of cevanine-type alkaloids as a class of natural antifibrotic agents.


Assuntos
Alcaloides , Fritillaria , Humanos , Fritillaria/química , Alcaloides/química , Raízes de Plantas/química , Tosse , Esteroides/química , Fator de Crescimento Transformador beta/análise
5.
Phytochemistry ; 219: 113985, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38237845

RESUMO

Ornithogalum thyrsoides Jacq belongs to the Asparagaceae family and is cultivated for ornamental purposes. The authors have previously reported several cholestane- and spirostan-type steroidal glycosides from O. thyrsoides. Conventional TLC analysis of the methanolic bulb extract of O. thyrsoides suggested the presence of unprecedented compounds; therefore, a detailed phytochemical investigation of the extract was performed and 35 steroidal glycosides (1-35), including 21 previously undescribed ones (1-21) were collected. The structures of 1-21 were determined mainly by analyses of their 1H and 13C NMR spectra with the aid of two-dimensional NMR spectroscopy. The isolated compounds were classified into three distinct groups: furostan-type (1, 2, 8-12, and 22), spirostan-type (3-7 and 23-26), and cholestane-type (13-21 and 27-35). Although the C/D-ring junction of the steroidal skeleton is typically trans-oriented, except for some cardiotonic and pregnane-type steroidal derivatives, 7 possess a cis C/D-ring junction. This is the first reported instance of such a configuration in spirostan-type steroidal derivatives, marking it as a finding of significant interest. Compounds 1-35 were evaluated for cytotoxicity against HL-60 human promyelocytic leukemia cells and SBC-3 human small-cell lung cancer cells. Compounds 3-6, 9, 17-21, 23-25, and 30-35 demonstrated cytotoxicity in a dose-dependent manner with IC50 values ranging from 0.000086 to 18 µM and from 0.00014 to 37 µM toward HL-60 and SBC-3 cells, respectively. Compound 19, which is obtained in a good yield and shows relatively potent cytotoxicity among the undescribed compounds, induces apoptosis in HL-60 cells, accompanied by arresting the cell cycle of HL-60 cells at the G2/M phase. In contrast, 19 causes oxidative stress-associated necrosis in SBC-3 cells. The cytotoxic mechanism of 19 is different between HL-60 and SBC-3 cells.


Assuntos
Colestanos , Leucemia , Neoplasias Pulmonares , Ornithogalum , Espirostanos , Humanos , Células HL-60 , Ornithogalum/química , Glicosídeos/química , Colestanos/química , Esteroides/farmacologia , Esteroides/química , Extratos Vegetais/farmacologia
6.
Steroids ; 204: 109362, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38278283

RESUMO

Research published between 2001 and 2022 on the functionalization of remote positions of steroids, as well as the use of this technique in the generation of biologically active compounds has been reviewed. In the first section of the analysis established and novel methods for activation of sites deemed to be remote were reported. A series of manganese- (mainly), rhodium-, ruthenium- and osmium-centered porphyrins as catalysts in the presence of PIDA as oxidant have effected hydroxylation at C-1, -5, -6, -7, -11, -14, -15, -16, -17, -20, -24 and -25. Dioxiranes have been utilized in inserting hydroxyl groups at the 5, 12, 14, 15, 16, 17, 20, 24 and 25 positions (tertiary centers for the most part). Alcohols at C-12 and -16 were oxidized further to ketones. The Schönecker oxidation, discovered and developed during the period, has revolutionized the selective functionalization at C-12 of steroids possessing a 17-keto group. In the presence of iron-centered PDP- and MCP-based catalysts, hydrogen peroxide and acetic acid, substrates tended to be hydroxylated at C-6 and -12, with further oxidation to ketones often accompanying this reaction. The hypohalite reaction, utilizing the more modern Suarez conditions (irradiation in the presence of iodine and PIDA), was reported to facilitate the insertion of a hydroxyl moiety five atoms away from an existing alcohol oxygen. Steroidal-3ß-diazoacetates tend to decompose on heating with di-rhodium-centered catalysts while activating carbons four or five atoms away. Chromium- and iron-based acetates were observed to functionalize C-5 and -25. Other reactions involving ring cleavage and halogenation, ketone irradiation and α-hydroxylation of ethers were also covered. The syntheses of compounds with marked biological activity from readily available steroids is described in the second section of the study. Cyclopamine, cephalostatin-1, ritterazine B and three polyhydroxypregnanaes (pergularin, utendin and tomentogenin) were generated in sequences in which a key step required hydroxylation at C-12 using the Schönecker reaction. A crucial stage in the preparation of cortistatin A, the saundersioside core, eurysterol A, 5,6-dihydroglaucogenin C, as well as clinostatins A and B involved the functionalization of C-18 or -19 utilizing hypohalite chemistry. The synthetic route to xestobergsterol A, pavonin-4-aglycone and ouagabagenin included a transformation where ketone irradiation played a part in either producing a Δ14 or a C-19 activated steroid. The radical relay reaction, where a 17α-chloro-steroid was formed, was central in the generation of pythocholic acid. The lead tetraacetate reaction was pivotal in the functionalization of C-19 during the synthesis of cyclocitrinol.


Assuntos
Ródio , Ródio/química , Esteroides/química , Hidroxilação , Álcoois , Cetonas , Ferro , Catálise
7.
J Pharm Biomed Anal ; 240: 115958, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38198886

RESUMO

LC-MS serves as a workhorse for chemical profile characterization of Chinese medicinal materials (CMMs) attributing to the ability of measuring fruitful MS/MS spectral information. However, it is laborious to extract the information belonging to the compounds-of-interest from the massive data matrixes even employing those well-defined post-acquisition data processing strategies. Here, efforts were devoted to propose an integrated strategy allowing rapid chemical homologs-focused data filtering through integrating the fit-for-purpose existing strategies, such as molecular weight imprinting (MWI), diagnostic fragment ion filtering (DFIF), neutral loss filtering (NLF), and isotope pattern filtering (IPF). Homologs-focused chemical characterization of a precious CMM namely Toad gall-bladder (Chinese name: Chandan) that is rich of diverse effective steroid sulfates, particularly bufogenin sulfates, bile acid sulfates and bilichol sulfates, was employed as a proof-of-concept. Recombinant human SULT2A1-catalyzed in vitro metabolism was undertaken to generate eight bufogenin sulfates to facilitate summarizing MS/MS spectral behaviors. After in-house data library construction and MS1 and MS2 spectral acquisition, data filtering was conducted as follows: 1) MWI and IPF was utilized in combination to capture deprotonated molecular ions and the 34S isotopic ions for the sulfates of those reported steroids; 2) m/z 79.9568 (SO3-·) and 96.9596 (HSO4-) were applied to DFIF; and 3) SO3 (79.9568 Da) served as the feature to achieve NLF. Those captured MS/MS information subsequently participated in tentatively structural annotation through applying those empirical mass fragmentation rules. As a result, 71 compounds including 7 bufogenin sulfates, 17 bile acid sulfates, 13 bilichol sulfates and a C-23 steroid sulfate were detected from Toad gall-bladder and thereof, 39 ones received plausible identities assignment. Above all, the steroid sulfates in Toad gall-bladder were profiled in depth, and more importantly, the proposed strategy should be a meaningful option for, but not limited to, submetabolome characterization in CMMs.


Assuntos
Espectrometria de Massas em Tandem , Bexiga Urinária , Humanos , Bexiga Urinária/metabolismo , Esteroides/química , Sulfatos/química , 60705 , Ácidos e Sais Biliares
8.
J Nat Prod ; 87(2): 252-265, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38294199

RESUMO

Eleven new steroidal alkaloids, along with nine known related compounds, were isolated from the bulbs of Fritillaria sinica. Seven pairs of diastereomers were identified, including six and four 20-deoxy cevanine-type steroidal alkaloid diastereomers with molecular weights of 413 and 415, respectively. Structures were elucidated based on spectroscopic data analysis, chemical derivatization, and single-crystal X-ray diffraction analysis. Compounds 5, 9, 11, 12, 16, and 20 exhibited significant in vitro cytotoxic activity against non-small-cell lung cancer with CC50 values from 6.8 ± 3.9 to 12 ± 5 µM.


Assuntos
Alcaloides , Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Fritillaria , Neoplasias Pulmonares , Humanos , Fritillaria/química , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Estrutura Molecular , Neoplasias Pulmonares/tratamento farmacológico , Alcaloides/química , Esteroides/química
9.
Nat Prod Res ; 38(4): 601-606, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36924396

RESUMO

Two new vernonioside K (1) and vernonioside L (2) and four known Δ7,9(11) stigmastane-type steroidal saponins-vernonioside B2 (3), vernoniacum B (4), vernonioside B1 (5), and vernoamyoside A (6)-were isolated from the leaves of Vernonia amygdalina. Their structures were determined by comprehensive spectroscopic analysis with one-dimensional nuclear magnetic resonance, two-dimensional nuclear magnetic resonance, and high-resolution mass spectrometry. All isolated compounds (1-6) were evaluated to determine their inhibitory effects on α-glucosidase and xanthine oxidase. Among them, two new compounds 1 and 2 showed significant inhibition of α-glucosidase with IC50 values of 78.56 ± 7.28 and 14.74 ± 1.57 (µM), respectively, comparable with acarbose as a positive control (127.53 ± 1.73 µM); none of these compounds inhibited xanthine oxidase activity. Compounds 1 and 2 are promising candidates for the development of antidiabetic agents from natural sources.


Assuntos
Saponinas , Vernonia , alfa-Glucosidases , Vernonia/química , Xantina Oxidase , Saponinas/farmacologia , Saponinas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Esteroides/química
10.
Bioorg Chem ; 143: 107029, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38091717

RESUMO

Prostate cancer is one of the most prevalent cancers in men leading to second most death causing cancer in men. Despite the availability of multiple treatment still the prevalence is high for prostate cancer. Steroidal antagonists associated with poor bioavailability, side effects while non-steroidal antagonists show serious side effects like gynecomastia. Therefore, there is a need of potential candidate for the treatment of prostate cancer with better bioavailability, good therapeutic effect and minimal side effects. In the same context, we have designed the series, SP1-SP25 based 3-phenyl-5-styryl-1,2,4-oxadiazole as the core structure. We successfully synthesized all 25 molecules in this series and characterized them using 1H, 13C NMR, and mass spectroscopy. Subsequently, we conducted MTT assays using PC-3 cells and observed that all the compounds exhibited a dose-dependent decrease in cell viability. Notably, compounds SP04, SP16, and SP19 demonstrated a significant decrease in cell viability and exhibited potent activity compared to the other synthesized molecules and standard drug bicalutamide. Among them, SP04 emerged as the one of the most potent compounds with an IC50 value of 238.13 nM and an 89.99 % inhibition of PC-3 cells, compared to synthesized molecules and standard drug bicalutamide. Furthermore, we conducted ROS assays and androgen receptor inhibition assays using the potent compound SP04 and bicalutamide. The results indicated that SP04 increased ROS production and decreased androgen receptor expression dose-dependent manner. Additionally, we conducted a docking study to analyse the interaction patterns within the active site of the androgen receptor. ADMET analysis revealed that all the compounds exhibited favorable physicochemical properties and manageable toxicity profiles.


Assuntos
Anilidas , Antineoplásicos , Nitrilas , Neoplasias da Próstata , Compostos de Tosil , Masculino , Humanos , Simulação de Acoplamento Molecular , Receptores Androgênicos/química , Antineoplásicos/química , Espécies Reativas de Oxigênio , Esteroides/química , Neoplasias da Próstata/tratamento farmacológico , Estrutura Molecular , Proliferação de Células , Relação Estrutura-Atividade , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral
11.
Chin J Nat Med ; 21(10): 789-800, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37879796

RESUMO

Five new saponins, including three steroid saponins, paristenoids A-C (1-3), and two triterpenoid saponins, paristenoids D-E (4-5), along with four known ones (6-9) were isolated from the rhizomes of Paris polyphylla var. stenophylla. The structures of the isolated compounds were identified mainly by detailed spectroscopic analysis, including extensive 1D and 2D NMR, MS, as well as chemical methods. Compound 3 is a new cyclocholestanol-type steroidal saponin with a rare 6/6/6/5/5 fused-rings cholestanol skeleton, and this skeleton has been first found from the genus Paris. The cytotoxicities of the isolated compounds against three human three glioma cell lines (U87MG, U251MG and SHG44) were evaluated, and compound 7 displayed certain inhibitory effect with IC50 values of 15.22 ± 1.73, 18.87 ± 1.81 and 17.64 ± 1.69 µmol·L-1, respectively.


Assuntos
Liliaceae , Saponinas , Triterpenos , Humanos , Rizoma/química , Esteroides/farmacologia , Esteroides/química , Liliaceae/química , Saponinas/química , Triterpenos/farmacologia , Triterpenos/análise
12.
J Agric Food Chem ; 71(40): 14814-14824, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37782472

RESUMO

Residues of endocrine disrupting steroid hormones in food might cause various diseases like cardiovascular diseases and breast and prostate cancers. Monitoring steroid hormone levels plays a vital role in ensuring food safety and exploring the pathogenic mechanism of steroid hormone-related diseases. Based on the Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction, a novel chemoselective probe, Azo-N3, which contains a reactive site N3, an imidazolium salt-based MS tag, and an azobenzene-based photoswitchable handle, was designed and synthesized to label ethynyl-bearing steroid hormones. The probe Azo-N3 was applied for the highly selective and sensitive detection of four ethynyl-bearing steroid hormones in food samples (milk, egg, and pork) by using ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The ionization efficiency of the labeled analytes could be increased by 6-105-fold, and such a labeled method exhibited satisfactory detection limits (0.04-0.2 µg/L), recovery (80.6-122.4%), and precision (RSDs% lower than 6.9%). Interestingly, the efficient immobilization of the probe Azo-N3 onto α-cyclodextrin (α-CD)-modified magnetic particles to construct a solid supported chemoselective probe Fe3O4-CD-Azo-N3 and UV light-controlled release of the labeled analytes from a magnetic support can be achieved by taking advantage of the photoswitched host-guest inclusion between the azobenzene unit and α-CD. The potential applications of Fe3O4-CD-Azo-N3 for labeling, capturing, and the photocontrolled release of the labeled steroid hormones were fully investigated by mass spectrometry imaging analysis. This work not only provides a sensitive and accurate method to detect steroid hormones in food but also opens a new avenue in designing solid supported chemoselective probes.


Assuntos
Hormônios , Espectrometria de Massas em Tandem , Humanos , Masculino , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Esteroides/química , Cromatografia Líquida de Alta Pressão/métodos
13.
Methods Enzymol ; 689: 277-301, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37802574

RESUMO

In mammals there are two 3-oxo-4-ene steroid reductases that generate either A/B-trans or A/B cis-ring junctions in the steroid nucleus known as steroid 5α- and 5ß- reductases, respectively. There is only one steroid 5ß- reductase in each species and these are members of the aldo-keto-reductase (AKR) protein superfamily. The corresponding human enzyme is AKR1D1, and it plays an essential role in bile-acid biosynthesis. Germline mutations in AKR1D1 give rise to bile-acid deficiency. Because of its central role in steroid metabolism and need for detailed structure-function studies there is a need to purify the enzyme to homogeneity and in high yield. We report the purification of milligram amounts of crystallographic quality homogeneous recombinant protein for structure-function studies and its characterization.


Assuntos
Oxirredutases , Esteroides , Animais , Humanos , Oxirredutases/química , Esteroides/química , Esteroides/metabolismo , Ácidos e Sais Biliares , Mamíferos/metabolismo
14.
Methods Enzymol ; 689: 387-431, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37802580

RESUMO

The "rediscovery" 11ß-hydroxyandrostenedione (11OHA4) placed the spotlight on this unique adrenal-derived hormone with researchers and clinicians once again focusing on the steroid's presence in endocrine pathology. Little was known about the steroid other than its chemical characterisation and that a mitochondrial cytochrome P450 enzyme catalysed the 11ß-hydroxylation of 11OHA4. The fact that neither the biosynthesis nor metabolism of 11OHA4 had been fully characterised presented an ideal opportunity to investigate the metabolic pathways. In addition, methodologies and analytical tools have improved vastly since 11OHA4 was first identified in the 1950s. Cell models, recombinant DNA technology and steroid quantification using liquid chromatography mass spectrometry have greatly facilitated investigations in the field of steroidogenesis. Evident from the structure is that 11OHA4 can be metabolised by hydroxysteroid dehydrogenases and reductases acting on the C4/C5 double bond and on functional moieties at specific carbons on the cyclopentane-perhydro-phenanthrene backbone of the steroid. In this chapter, the biosynthesis and metabolism of 11OHA4 is followed using two strategies that complement each another; (i) human cell models either transiently transfected with recombinant DNA or expressing endogenous steroidogenic enzymes and (ii) steroid identification and quantification using high resolution mass spectrometry. These methodologies have proven invaluable in the determination of 11OHA4's metabolic route. Both strategies are presented with the focus on the accurate identification and quantification of steroids using UHPLC-MS/MS and UPC2-MS/MS. The protocols described in this chapter lay a sound foundation which can aid the researcher and be adapted and implement in future studies.


Assuntos
Androstenodiona , Espectrometria de Massas em Tandem , Humanos , Androstenodiona/química , Androstenodiona/metabolismo , DNA Recombinante/metabolismo , Esteroides/química , Esteroides/metabolismo , Redes e Vias Metabólicas
15.
Phytochemistry ; 215: 113870, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37734511

RESUMO

Seven previously undescribed lanostane triterpenoids, ganoderic acid M1 (1), M2 (2), M3 (3), M4 (4), M5 (5), M6 (6), and M7 (7), together with eight known compounds, were isolated from mycelia of the basidiomycete Ganoderma sinense (Ganodermataceae). The structures of all compounds were elucidated by spectroscopic analysis. The possible biosynthetic pathway of these fifteen triterpenoids was proposed. Some of the compounds were evaluated for their anti-inflammatory activity by measuring the production of nitric oxide (NO), TNF-α, and IL-6 in RAW264.7 macrophage cells induced by lipopolysaccharide. Lanosta-7,9(11),24-trien-3ß,15α,22ß-triacetoxy-26-oic acid (14) exhibited the strongest inhibition of NO production with an IC50 of 0.6 ± 0.1 µM and completely inhibited the secretion of TNF-α and IL-6 at 10 µM. The structure-activity relationship of the anti-inflammatory activity is discussed.


Assuntos
Ganoderma , Triterpenos , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Carpóforos/química , Triterpenos/química , Ganoderma/química , Esteroides/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , Estrutura Molecular
16.
Biomolecules ; 13(9)2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37759820

RESUMO

The glutathione transferase A3-3 (GST A3-3) homodimeric enzyme is the most efficient enzyme that catalyzes isomerization of the precursors of testosterone, estradiol, and progesterone in the gonads of humans and horses. However, the presence of GST A3-3 orthologs with equally high ketosteroid isomerase activity has not been verified in other mammalian species, even though pig and cattle homologs have been cloned and studied. Identifying GSTA3 genes is a challenge because of multiple GSTA gene duplications (e.g., 12 in the human genome); consequently, the GSTA3 gene is not annotated in most genomes. To improve our understanding of GSTA3 gene products and their functions across diverse mammalian species, we cloned homologs of the horse and human GSTA3 mRNAs from the testes of a dog, goat, and gray short-tailed opossum, the genomes of which all currently lack GSTA3 gene annotations. The resultant novel GSTA3 mRNA and inferred protein sequences had a high level of conservation with human GSTA3 mRNA and protein sequences (≥70% and ≥64% identities, respectively). Sequence conservation was also apparent for the 12 residues of the "H-site" in the 222 amino acid GSTA3 protein that is known to interact with the steroid substrates. Modeling predicted that the dog GSTA3-3 may be a more active ketosteroid isomerase than the corresponding goat or opossum enzymes. However, expression of the GSTA3 gene was higher in liver than in other dog tissue. Our results improve understanding of the active sites of mammalian GST A3-3 enzymes, inhibitors of which might be useful for reducing steroidogenesis for medical purposes, such as fertility control or treatment of steroid-dependent diseases.


Assuntos
Glutationa Transferase , Cabras , Humanos , Cavalos/genética , Cães , Animais , Bovinos , Suínos , RNA Mensageiro/genética , Glutationa Transferase/metabolismo , Cabras/genética , Cabras/metabolismo , Gambás/genética , Gambás/metabolismo , Esteroides/química , Isomerases/genética , Isomerases/metabolismo , Cetosteroides
17.
Phytochemistry ; 213: 113782, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37451564

RESUMO

A phytochemical investigation of the dichloromethane soluble fraction of the ethanolic extract obtained from the roots of Marsdenia tenacissima led to the discovery of the sixteen undescribed pregnane C21 steroids (1-16) and isolation of eleven known C21 steroidal analogues (17-27). Their chemical structures were elucidated by one- and two-dimensional nuclear magnetic resonance spectroscopy and, high resolution-electrospray ionization mass spectrometry and their absolute configurations were determined using electronic circular dichroism or single-crystal X-ray diffraction. The in vitro anti-proliferative effects of 1-16 were evaluated against HepG2 (human hepatocellular cancer), A549 (lung cancer), and MCF-7 (human breast cancer) cell lines. Even though some of them showed moderate cytotoxic activities, marsectohexol derivative 12 exhibited significant cytotoxicity against A549 cells with an IC50 value of 5.2 µM.


Assuntos
Antineoplásicos , Marsdenia , Humanos , Marsdenia/química , Esteroides/farmacologia , Esteroides/química , Pregnanos/química , Extratos Vegetais/química
18.
Int J Mol Sci ; 24(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37511620

RESUMO

Bile acid anions are steroidal biosurfactants that form primary micelles due to the hydrophobic effect. At higher concentrations of some bile acid anions, secondary micelles are formed; hydrogen bonds connect primary micelles. Monoketo derivatives of cholic acid, which have reduced membrane toxicity, are important for biopharmaceutical examinations. The main goal is to explain why the processes of formation of primary and secondary micelles are separated from each other, i.e., why secondary micelles do not form parallel to primary micelles. The association of the anion of 7-oxodeoxycholic acid (a monoketo derivative of cholic acid) is observed through the dependence of the spin-lattice relaxation time on total surfactant concentration T1 = f(CT). On the function T1 = f(CT), two sharp jumps of the spin-lattice relaxation time are obtained, i.e., two critical micellar concentrations (CMC). The aggregation number of the micelle at 50 mM total concentration of 7-oxodeoxycholic acid anions in the aqueous solution is 4.2 ± 0.3, while at the total concentration of 100 mM the aggregation number is 9.0 ± 0.9. The aggregation number of the micelle changes abruptly in the concentration interval of 80-90 mM (the aggregation number determined using fluorescence measurements). By applying Le Chatelier's principle, the new mechanism of formation of secondary micelles is given, and the decoupling of the process of formation of primary and secondary micelles at lower concentrations of monomers (around the first critical micellar concentration) and the coupling of the same processes at higher equilibrium concentrations of monomers (around the second critical micellar concentration) is explained. Stereochemically and thermodynamically, a direct mutual association of primary micelles is less likely, but monomeric units are more likely to be attached to primary micelles, i.e., 7-oxodeoxycholic acid anions.


Assuntos
Ácidos e Sais Biliares , Micelas , Ácido Cólico/química , Esteroides/química , Fármacos Gastrointestinais , Ânions
19.
Fitoterapia ; 169: 105603, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37421992

RESUMO

Three previously undescribed steroidal constituents including two sterols (1-2) and one pregnane-type steroidal glycoside (6), along with nineteen known ones (3-5, 7-22), were isolated from the 80% alcohol extraction of Solanum nigrum L. Their structures and the absolute configurations were established by analysis of the extensive spectroscopic data (1H/13 NMR, 1H1H COSY, HSQC, HMBC, and NOESY), and/or by comparisons of the experimental electronic circular dichroism (ECD) spectra with those calculated ones by TDDFT method. Further, a MTT assay was applied to demonstrate that compounds 1-4, 6-12, 18, and 22 exhibited significant cytotoxic activities against SW480 cells, and compounds 1-4, 6-14, and 16-22 showed significant cytotoxic activities against Hep3B cells.


Assuntos
Fitosteróis , Solanum nigrum , Solanum , Solanum nigrum/química , Estrutura Molecular , Esteroides/farmacologia , Esteroides/química , Espectroscopia de Ressonância Magnética , Fitosteróis/farmacologia , Solanum/química
20.
Chem Biodivers ; 20(8): e202300821, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37376927

RESUMO

Three new steroids, along with two known related analogs, were isolated from the Xisha Island soft coral Lobophytum sarcophytoides. The structures and absolute configurations of the new compounds were elucidated by extensive spectroscopic data analyses, time dependent density functional theory electronic circular dichroism calculation, and comparison with the spectral data previously reported in the literature. In in vitro bioassay, four compounds showed interesting suppressive effects on lipopolysaccharide (LPS) induced inflammation in BV-2 microglial cells at 10 µM level.


Assuntos
Antozoários , Diterpenos , Animais , Antozoários/química , Esteroides/farmacologia , Esteroides/química , Anti-Inflamatórios/farmacologia , China , Lipopolissacarídeos/farmacologia , Diterpenos/química , Estrutura Molecular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...