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1.
J Hazard Mater ; 470: 134116, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38547753

RESUMO

Microplastic (MP), as a new pollutant, not only affects the growth and development of plants but also may affect the secondary metabolites of plants. The anti-tumor role of Pinellia ternata is related to secondary metabolites. The role of brassinolide (BR) in regulating plant resistance is currently one of the research hotspots. The paper mainly explores the regulation of BR on growth and physiology of Pinellia ternata under MP stress. The experimental design includes two levels of MP (0, 1%) and two levels of BR (0, 0.1 mg/L). MP led to a marked reduction in plant height (15.0%), Fv/Fm (3.2%), SOD and APX activity (15.0%, 5.1%), whereas induced an evident raise in the rate of O2·- production (29.6%) and GSH content (4.4%), as well as flavonoids (6.8%), alkaloids (75%), and ß-sitosterol (26.5%) contents. Under MP addition, BR supply significantly increased plant height (15.7%), aboveground and underground biomass (16.1%, 10.3%), carotenoid and GSH content (11.8%, 4.2%), Fv/Fm (2.9%), and activities of SOD, GR, and MDHAR (32.2%, 21.08%, 20.9%). These results indicate that MP suppresses the growth of P. ternata, although it promotes secondary metabolism. BR can alleviate the inhibitory effect of MP on growth by improving photosynthesis, redox homeostasis, and the AsA-GSH cycle.


Assuntos
Brassinosteroides , Glutationa , Homeostase , Oxirredução , Fotossíntese , Pinellia , Esteroides Heterocíclicos , Fotossíntese/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Glutationa/metabolismo , Brassinosteroides/metabolismo , Pinellia/metabolismo , Pinellia/efeitos dos fármacos , Pinellia/crescimento & desenvolvimento , Esteroides Heterocíclicos/farmacologia , Plásticos/metabolismo , Sitosteroides/metabolismo , Flavonoides/metabolismo
2.
Am J Dermatopathol ; 44(10): 753-755, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36122334

RESUMO

ABSTRACT: We report a noteworthy case of a 10-year-old girl who presented with papular and nodular lesions on the skin that were clinically and histologically mistaken for progressive nodular histiocytosis. During the clinical management of the patient, the high lipid levels raised the suspicion of lipid metabolism disease and helped us to make the correct diagnosis of sitosterolemia. In sitosterolemia, proper management such as restriction of plant sterol intake and administration of cholesterol absorption inhibitor can improve prognosis.


Assuntos
Histiocitose , Fitosteróis , Dermatopatias , Xantomatose , Criança , Colesterol , Feminino , Histiocitose/diagnóstico , Humanos , Hipercolesterolemia , Enteropatias , Erros Inatos do Metabolismo Lipídico , Fitosteróis/efeitos adversos , Sitosteroides/metabolismo , Dermatopatias/diagnóstico , Xantomatose/diagnóstico , Xantomatose/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(7)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35131946

RESUMO

Tomato (Solanum lycopersicum) produces a wide range of volatile chemicals during fruit ripening, generating a distinct aroma and contributing to the overall flavor. Among these volatiles are several aromatic and aliphatic nitrogen-containing compounds for which the biosynthetic pathways are not known. While nitrogenous volatiles are abundant in tomato fruit, their content in fruits of the closely related species of the tomato clade is highly variable. For example, the green-fruited species Solanum pennellii are nearly devoid, while the red-fruited species S. lycopersicum and Solanum pimpinellifolium accumulate high amounts. Using an introgression population derived from S. pennellii, we identified a locus essential for the production of all the detectable nitrogenous volatiles in tomato fruit. Silencing of the underlying gene (SlTNH1;Solyc12g013690) in transgenic plants abolished production of aliphatic and aromatic nitrogenous volatiles in ripe fruit, and metabolomic analysis of these fruit revealed the accumulation of 2-isobutyl-tetrahydrothiazolidine-4-carboxylic acid, a known conjugate of cysteine and 3-methylbutanal. Biosynthetic incorporation of stable isotope-labeled precursors into 2-isobutylthiazole and 2-phenylacetonitrile confirmed that cysteine provides the nitrogen atom for all nitrogenous volatiles in tomato fruit. Nicotiana benthamiana plants expressing SlTNH1 readily transformed synthetic 2-substituted tetrahydrothiazolidine-4-carboxylic acid substrates into a mixture of the corresponding 2-substituted oxime, nitro, and nitrile volatiles. Distinct from other known flavin-dependent monooxygenase enzymes in plants, this tetrahydrothiazolidine-4-carboxylic acid N-hydroxylase catalyzes sequential hydroxylations. Elucidation of this pathway is a major step forward in understanding and ultimately improving tomato flavor quality.


Assuntos
Frutas/química , Oxigenases de Função Mista/metabolismo , Nitrogênio/metabolismo , Odorantes/análise , Sitosteroides/metabolismo , Solanum lycopersicum/metabolismo , Frutas/metabolismo , Oxigenases de Função Mista/genética , Nitrogênio/química , Compostos Orgânicos Voláteis
4.
Oxid Med Cell Longev ; 2021: 4883398, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603597

RESUMO

Many traditional Chinese medicines (TCMs) with skin-whitening properties have been recorded in the Ben-Cao-Gang-Mu and in folk prescriptions, and some literature confirms that their extracts do have the potential to inhibit pigmentation. However, no systematic studies have identified the specific regulatory mechanisms of the potential active ingredients. The aim of this study was to screen the ingredients in TCMs that inhibit skin pigmentation through a network pharmacology system and to explore underlying mechanisms. We identified 148 potential active ingredients from 14 TCMs, and based on the average "degree" of the topological parameters, the top five TCMs (Fructus Ligustri Lucidi, Hedysarum multijugum Maxim., Ampelopsis japonica, Pseudobulbus Cremastrae Seu Pleiones, and Paeoniae Radix Alba) that were most likely to cause skin-whitening through anti-inflammatory processes were selected. Sitogluside, the most common ingredient in the top five TCMs, inhibits melanogenesis in human melanoma cells (MNT1) and murine melanoma cells (B16F0) and decreases skin pigmentation in zebrafish. Furthermore, mechanistic research revealed that sitogluside is capable of downregulating tyrosinase (TYR) expression by inhibiting the ERK and p38 pathways and inhibiting TYR activity. These results demonstrate that network pharmacology is an effective tool for the discovery of natural compounds with skin-whitening properties and determination of their possible mechanisms. Sitogluside is a novel skin-whitening active ingredient with dual regulatory effects that inhibit TYR expression and activity.


Assuntos
Farmacologia em Rede/métodos , Sitosteroides/farmacologia , Pigmentação da Pele/efeitos dos fármacos , Animais , Arbutina/química , Arbutina/metabolismo , Sítios de Ligação , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Bases de Dados de Compostos Químicos , Regulação para Baixo/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Medicina Tradicional Chinesa , Melaninas/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Sitosteroides/química , Sitosteroides/metabolismo
5.
Protein Pept Lett ; 28(3): 276-281, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32798371

RESUMO

BACKGROUND: Although glucocorticoids (GCs) are characterized as powerful agents to treat inflammatory afflictions, they are accompanied by metabolic side effects which limit their usage. ß-Sitosterol, as a minor component found in extraction of vegetable oil, was reported to have anti-inflammatory effects in RAW 264.7 cells. OBJECTIVE: To test whether ß-sitosterol has an effect to dissociate transrepression from transactivation as a selective novel GR binder, this work evaluated the dissociated characteristics of ß-sitosterol. METHODS: The probable binding interaction between ß-sitosterol and GR was explored by molecular docking. The GR transcriptional activity of ß-sitosterol was assessed in the reporter gene assay. The ability of ß-sitosterol to modulate the transactivation and transrepression of GR was evaluated by real-time quantitative PCR analysis. RESULTS AND DISCUSSION: In the present study, ß-sitosterol treatment cannot induce GR-mediated transactivation. ß-Sitosterol exerted a potential to inhibited the expression of GR target transrepressed gene without activating the expression of GR transactivation dependent gene. Molecular docking demonstrated that ß-Sitosterol was able to bind the ligand binding domain of GR but unable to induce GR activation. CONCLUSION: This work offers evidence that ß-sitosterol may serve as a selective GR modulator.


Assuntos
Simulação de Acoplamento Molecular , Receptores de Glucocorticoides/química , Sitosteroides/química , Animais , Células HeLa , Células Hep G2 , Humanos , Camundongos , Células RAW 264.7 , Receptores de Glucocorticoides/metabolismo , Sitosteroides/metabolismo
6.
Biomed Pharmacother ; 131: 110702, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32882583

RESUMO

Phytosterols are bioactive compounds that are naturally present in plant cell membranes with chemical structure similar to the mammalian cell- derived cholesterol. They are highly present in lipid-rich plant foods such as nuts, seed, legumes and olive oil. Among various phytosterols, ß-sitosterol (SIT) is the major compound, found plentiful in plants. It has been evidenced in many in-vitro and in-vivo studies that SIT possesses various biological actions such as anxiolytic & sedative effects, analgesic, immunomodulatory, antimicrobial, anticancer, anti - inflammatory, lipid lowering effect, hepatoprotective, protective effect against NAFLD and respiratory diseases, wound healing effect, antioxidant and anti-diabetic activities. In this review, in order to compile the sources, characterization, biosynthesis, pharmacokinetics, antioxidant and anti-diabetic activities of SIT, classical and online-literature were studied which includes the electronic search (Sci Finder, Pubmed, Google Scholar, Scopus, and Web of Science etc) and books on photochemistry. The experimental studies on SIT gives a clear evidence that the potential phytosterol can be used as supplements to fight against life threatening diseases. High potential of this compound, classifies it as the notable drug of the future. Therefore, immense researches regarding its action at molecular level on life threatening diseases in humans are highly endorsed.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Suplementos Nutricionais , Sitosteroides/administração & dosagem , Animais , Antioxidantes/farmacologia , Humanos , Sitosteroides/química , Sitosteroides/metabolismo , Sitosteroides/farmacologia
7.
Arch Biochem Biophys ; 689: 108472, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32590065

RESUMO

ß-Sitosterol (ßSito) is the most abundant phytosterol found in elevated concentrations in vegetable oils, nuts, seeds, cereals, fruits, and in many phytosterol-enriched foods. Although the benefits, there is a concern in terms of food quality and health due to the increasing consumption of phytosterols and the possible adverse side effects of their oxidation products, oxyphytosterols. ßSito has a similar structure to cholesterol, with an unsaturated double bond at C5-C6, which is susceptible to oxidation by reactive oxygen species like ozone, generating oxyphytosterols. In this work we propose a mechanism of formation of three oxyphytosterols 2-[(7aR)-5-[(1R,4S)-4-hydroxy-1-methyl-2-oxocyclohexyl]-1,7a-dimethyl-1,2,3,3a,4,5,6,7- octahydroinden-4-yl] acetaldehyde (ßSec), (2-[(7aR)-5-[(2R,5S)-5-hydroxy-2-methyl-7-oxo-oxepan- 2-yl]-1,7a-dimethyl-1,2,3,3a,4,5,6,7-octahydroinden-4- yl] acetaldehyde (ßLac) and 2-((7aR)-5-((1R,4S)-4-hydroxy-1-methyl-2- oxocyclohexyl)-1,7a-dimethyloctahydro-1Hinden-4-yl) acetic acid (ßCOOH) generated by ozonization of ßSito, through their synthesis and molecular characterization. The cytotoxic effect of ßSito and its main oxyphytosterol ßSec was evaluated and both reduced the HepG2 cell viability.


Assuntos
Ozônio/metabolismo , Fitosteróis/metabolismo , Sitosteroides/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Oxirredução , Fitosteróis/química , Fitosteróis/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Sitosteroides/química , Sitosteroides/toxicidade
8.
Biosci Rep ; 40(7)2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32579186

RESUMO

It is controversial whether atherosclerosis is linked to increased intestinal cholesterol absorption or synthesis in humans. The aim of the present study was to relate atherosclerosis to the measurements of plasma markers of cholesterol synthesis (desmosterol, lathosterol) and absorption (campesterol, sitosterol). In healthy male (n=344), non-obese, non-diabetics, belonging to the city of São Paulo branch of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), we measured in plasma these non-cholesterol sterol markers, together with their anthropometric, dietary parameters, traditional atherosclerotic risk factors, and blood chemistry, coronary arterial calcium score (CAC), and ultrasonographically measured common carotid artery intima-media thickness (CCA-IMT). Cases with CAC>zero had the following parameters higher than cases with CAC = zero: age, waist circumference (WC), plasma total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and non-high density lipoprotein-cholesterol (non HDL-C). Plasma desmosterol and campesterol, duly corrected for TC, age, body mass index (BMI), waist circumference (WC), hypertension, smoking, and the homeostasis model assessment-insulin resistance (HOMA-IR) correlated with CAC, but not with CCA-IMT. The latter related to increased age, BMI, waist circumference (WC), and systolic blood pressure (SBP). Plasma HDL-C concentrations did not define CAC or CCA-IMT degrees, although in relation to the lower tertile of HDL-C in plasma the higher tertile of HDL-C had lower HOMA-IR and concentration of a cholesterol synthesis marker (desmosterol). Present work indicated that increased cholesterol synthesis and absorption represent primary causes of CAD, but not of the common carotid artery atherosclerosis.


Assuntos
Aterosclerose/diagnóstico , Cálcio/análise , Vasos Coronários/química , Adulto , Idoso , Aterosclerose/sangue , Biomarcadores/sangue , Biomarcadores/metabolismo , Índice de Massa Corporal , Brasil , Artéria Carótida Primitiva/diagnóstico por imagem , Espessura Intima-Media Carotídea , Colesterol/análogos & derivados , Colesterol/sangue , Colesterol/metabolismo , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Vasos Coronários/diagnóstico por imagem , Estudos Transversais , Desmosterol/sangue , Desmosterol/metabolismo , Feminino , Humanos , Absorção Intestinal , Mucosa Intestinal/metabolismo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fitosteróis/sangue , Fitosteróis/metabolismo , Estudos Prospectivos , Sitosteroides/sangue , Sitosteroides/metabolismo , Tomografia Computadorizada por Raios X , Ultrassonografia
9.
Poult Sci ; 99(3): 1400-1408, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32111314

RESUMO

This research investigated effects of dietary ß-sitosterol addition at different levels on serum lipid levels, immune function, oxidative status, and intestinal morphology in broilers. One-day-old broiler chicks were allocated to 5 groups of 6 replicates. Chickens in the 5 groups were fed a basal diet supplemented with 0 (control group), 40, 60, 80, and 100 mg/kg of ß-sitosterol for 42 D, respectively. ß-Sitosterol linearly decreased (P < 0.05) concentrations of serum total cholesterol, jejunal tumor necrosis factor α (TNF-α), and ileal interleukin 1ß (IL-1ß) and mRNA relative expressions levels of jejunal TLR4 and ileal MyD88, whereas it linearly increased (P < 0.05) contents of jejunal immunoglobulin G (IgG), ileal secreted IgA and glutathione, jejunal catalase activity and Nrf2 mRNA relative expression level, villus height (VH), and VH-to-crypt depth (CD) ratio (VH:CD) in the jejunum and ileum. Linear and quadratic increases (P < 0.05) in absolute and relative spleen weight were observed by dietary ß-sitosterol, whereas malondialdehyde (MDA) concentration in the jejunum and ileum followed the opposite trend (P < 0.05). Compared with the control group, dietary ß-sitosterol at higher than or equal to 60 mg/kg level decreased (P < 0.05) contents of serum total cholesterol, ileal MDA, and jejunal TLR4 mRNA relative expression level, whereas it increased (P < 0.05) absolute spleen weight and ileal glutathione content. Higher than or equal to 80 mg/kg level of ß-sitosterol enhanced (P < 0.05) jejunal IgG concentration, VH, catalase activity, and Nrf2 relative expression level and ileal secreted IgA content, but reduced (P < 0.05) ileal IL-1ß content and MyD88 mRNA relative expression level. ß-Sitosterol addition at 60 and 80 mg/kg levels increased (P < 0.05) relative spleen weight, whereas it decreased (P < 0.05) jejunal MDA accumulation. Moreover, 100 mg/kg level of ß-sitosterol reduced (P < 0.05) jejunal TNF-α level, but it increased (P < 0.05) VH in the jejunum and VH:CD in the jejunum and ileum. Accordingly, dietary ß-sitosterol supplementation could regulate serum cholesterol level, promote immune function, and improve intestinal oxidative status and morphology in broilers.


Assuntos
Galinhas/fisiologia , Imunidade Inata/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Lipídeos/sangue , Estresse Oxidativo/efeitos dos fármacos , Sitosteroides/metabolismo , Ração Animal/análise , Animais , Galinhas/sangue , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Intestinos/anatomia & histologia , Distribuição Aleatória , Sitosteroides/administração & dosagem
10.
Biosci Biotechnol Biochem ; 84(7): 1521-1528, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32183612

RESUMO

Sterols are verified to be able to produce polycyclic aromatic hydrocarbons during its pyrolysis. In this study, a kind of Aspergillus fumigatus (LSD-1) was isolated from cigar leaves, and the biosorption effects on the stigmasterol, ß-sitosterol, campesterol, cholesterol, and ergosterol by using living and dead biomass of LSD-1 were investigated. The results showed that both living and dead biomass could efficiently remove these sterols in aqueous solution and tobacco waste extract (TWE). Interestingly, compared with the living biomass of LSD-1, the dead biomass of LSD-1 not only kept a high adsorption efficiency but also did not produce ergosterol. Overall, dead biomass of LSD-1 was a more suitable biosorbent to sterols in TWE. Furthermore, Brunner-Emmet-Teller (BET), Fourier transformed infrared spectrometer (FTIR) and scanning electron microscope (SEM) analysis were used to explore the biosorption process of living and dead biomass and their differences, suggesting that the biosorption of sterols was a physical process.


Assuntos
Absorção Fisiológica , Aspergillus fumigatus/metabolismo , Colesterol/análogos & derivados , Ergosterol/metabolismo , Nicotiana/química , Nicotiana/microbiologia , Fitosteróis/metabolismo , Extratos Vegetais/metabolismo , Sitosteroides/metabolismo , Estigmasterol/metabolismo , Biodegradação Ambiental , Biomassa , Colesterol/metabolismo , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Folhas de Planta/química , Folhas de Planta/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/metabolismo
11.
Nat Prod Res ; 34(16): 2363-2366, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30600703

RESUMO

Aloe vera leaf contains some bioactive compounds that have a strong binding affinity toward estrogen receptor as compared to standard drug tamoxifen. In this study, we have found that the IC50 of Aloe vera leaf extract against breast cancer cell line (MCF-7) is 23 µg/mL which is much lower than the IC50 (332 µg/mL) of Aloe vera leaf extract against non-cancerous cell line (NIH-3T3). We have also calculated the total concentration of phenolic acid (385.662 µg/mL), flavonoids (160.402 µg/mL) and alkaloids (276.754 µg/mL) in Aloe vera leaf extract. The free radical scavenging activity of Aloe vera leaf extract is 67% to 89% (at 50 to 300 µg/ml). Our virtual molecular docking study suggests that bioactive compounds like Aloe-emodin (-8.8 Kcal/mol), 7-hydroxy-2,5 dimethylchromone (-7.5 Kcal/mol), Beta-sitosterol (-7.3 Kcal/mol) etc. have a greater binding affinity toward estrogen alpha receptor as compared to standard drug Tamoxifen (-6.4 Kcal/mol). [Formula: see text].


Assuntos
Aloe/química , Antineoplásicos/isolamento & purificação , Neoplasias da Mama/tratamento farmacológico , Extratos Vegetais/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Emodina/metabolismo , Receptor alfa de Estrogênio/metabolismo , Flavonoides/análise , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Extratos Vegetais/metabolismo , Sitosteroides/metabolismo
12.
Planta ; 250(6): 2033-2046, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31542810

RESUMO

MAIN CONCLUSION: ß-sitosterol influences amino acids, carbohydrates, organic acids, and other metabolite metabolism and homeostasis largely contributing to better tolerance to water stress in white clover. ß-sitosterol (BS) could act as an important plant growth regulator when plants are subjected to harsh environmental conditions. Objective of this study was to examine effects of BS on growth and water stress tolerance in white clover based on physiological responses and metabolomics. White clover was pretreated with or without BS and then subjected to water stress for 7 days in controlled growth chambers. Physiological analysis demonstrated that exogenous application of BS (120 µM) could significantly improve stress tolerance associated with better growth performance and photosynthesis, higher leaf relative water content, and less oxidative damage in white clover in response to water stress. Metabolic profiling identified 78 core metabolites involved in amino acids, organic acids, sugars, sugar alcohols, and other metabolites in leaves of white clover. For sugars and sugar alcohol metabolism, the BS treatment enhanced the accumulation of fructose, glucose, maltose, and myo-inositol contributing to better antioxidant capacity, growth maintenance, and osmotic adjustment in white clover under water stress. The application of BS was inclined to convert glutamic acid into proline, 5-oxoproline, and chlorophyll instead of going to pyruvate and alanine; the BS treatment did not significantly affect intermediates of tricarboxylic acid cycle (citrate, aconitate, and malate), but promoted the accumulation of other organic acids including lactic acid, glycolic acid, glyceric acid, shikimic acid, galacturonic acid, and quinic acid in white clover subjected to water stress. In addition, cysteine, an important antioxidant metabolite, was also significantly improved by BS in white clover under water stress. These altered amino acids and organic acids metabolism could play important roles in growth maintenance and modulation of osmotic and redox balance against water stress in white clover. Current findings provide a new insight into BS-induced metabolic homeostasis related to growth and water stress tolerance in plants.


Assuntos
Reguladores de Crescimento de Plantas/fisiologia , Sitosteroides/metabolismo , Trifolium/metabolismo , Membrana Celular/metabolismo , Desidratação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metabolômica , Estresse Oxidativo , Fotossíntese , Reguladores de Crescimento de Plantas/metabolismo , Trifolium/crescimento & desenvolvimento , Trifolium/fisiologia
13.
Eur J Pharmacol ; 855: 112-123, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31059712

RESUMO

Daucosterol (DS) is a plant phytosterol which is shown to induce oxidative stress mediated apoptosis in various cancer cell lines. However, the molecular mechanism underlying its cellular action has not been documented against Non- Small Cell Lung Cancer (NSCLC). Therefore, we attempted to decipher the mechanisms responsible for DS-induced anti-proliferation on human NSCLC cells. The present study showed, DS strongly inhibits the growth of A549 cells after 72 h time point with an IC50 value of ∼20.9 µM. Further DS elicits increased reactive oxygen species level and promote intrinsic apoptotic cell death on A549 cells as evidenced by increased expression of caspase-3, caspase-9, Bax, PARP inactivation, cytochrome-c release, and diminished expression of bcl-2 protein. DS failed to display its apoptotic actions upon pretreatment with the reactive oxygen species inhibitor NAC (N-acetyl cysteine). Indeed, apoptotic signal which was enhanced through p53/p21 activation and knockdown of p53 expression also moderately affected the DS induced apoptosis. In addition, DS preferentially inhibited the cell growth of p53 wild-type NSCLC cell lines than the mutant p53 models. Further, we show that inhibition of Thioredoxin (TrxR) redox system is principally associated with DS induced oxidative stress mediated apoptotic cell death on A549 cells. Moreover, we also demonstrated that DS stably interacted with serine residues in TrxR active sites. The obtained results confirmed that the anti-proliferative mechanism and increased reactive oxygen species level of DS was associated with down-regulation of TrxR1 pathway which triggers the p53 mediated intrinsic apoptotic mode of cell death in NSCLC cells.


Assuntos
Apoptose/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sitosteroides/farmacologia , Tiorredoxina Redutase 1/metabolismo , Tiorredoxina Dissulfeto Redutase/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Células A549 , Regulação para Baixo/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Oxirredução/efeitos dos fármacos , Conformação Proteica , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sitosteroides/metabolismo , Termodinâmica , Tiorredoxina Redutase 1/química
14.
J Agric Food Chem ; 66(45): 11943-11956, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30350970

RESUMO

Owing to the poor ability of cells to decompose triglycerides, most studies of edible oil have depended on animal or clinical trials. However, such trials are expensive and time-consuming, and the results are limited to considerable individual differences. This is the first study to comprehensively investigate the effect of different oils on the lipid accumulation and reactive oxygen species (ROS) production in HepG2 cells by hydrolyzing oil to fatty acids with integrated fat content. In addition, the key components of fatty acid composition, phytosterol, polyphenols, and tocopherol/tocotrienol in different oils, contributing to a decrease in content of lipid accumulation, cholesterol, ROS, and malondialdehyde (MDA), were analyzed using multivariate analysis. The results showed that the lipid accumulation content of coconut oil, Pu'er tea oil, olive oil, and flaxseed oil at a concentration of 200 µM decreased by 45.98 ± 0.75, 50.35 ± 1.37, 40.43 ± 2.44, and 42.76 ± 1.88%, respectively, compared with the lard. In addition, the ROS contents of Pu'er tea oil, olive oil, and flaxseed oil had no significant difference from that of control cells ( p < 0.05). In the results, (3ß,5α)-stigmastan-3-yl, cholane-5,20(22)-diene-3b-ph, and ß-sitosterol were determined to be the key components in edible oils associated with lipid accumulation and ROS production.


Assuntos
Metabolismo dos Lipídeos , Óleos de Plantas/química , Óleos de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Colesterol/metabolismo , Células Hep G2 , Humanos , Malondialdeído/metabolismo , Polifenóis/análise , Polifenóis/metabolismo , Sitosteroides/análise , Sitosteroides/metabolismo , Triglicerídeos/metabolismo
15.
J Biomol Struct Dyn ; 36(1): 195-208, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-27960611

RESUMO

Beta-sitosterol (ß-SITO), a phytosterol present in many edible vegetables, has been reported to possess antineoplastic properties and cancer treatment potential. We have shown previously that it binds at a unique site (the 'SITO-site') compared to the colchicine binding site at the interface of α- and ß-tubulin. In this study, we investigated the anticancer efficacy of ß-SITO against invasive breast carcinoma using MCF-7 cells. Since 'isotypes' of ß-tubulin show tissue-specific expression and many are associated with cancer drug resistance, using computer-assisted docking and atomistic molecular dynamic simulations, we also examined its binding interactions to all known isotypes of ß-tubulin in αß-tubulin dimer. ß-SITO inhibited MCF-7 cell viability by up to 50%, compared to vehicle-treated control cells. Indicating its antimetastatic potential, the phytosterol strongly inhibited cell migration. Immunofluorescence imaging of ß-SITO-treated MCF-7 cells exhibited disruption of the microtubules and chromosome organization. Far-UV circular dichroism spectra indicated loss of helical stability in tubulin when bound to ß-SITO. Docking and MD simulation studies, combined with MM-PBSA and MM-GBSA calculations revealed that ß-SITO preferentially binds with specific ß-tubulin isotypes (ßII and ßIII) in the αß-tubulin dimer. Both these ß-tubulin isotypes have been implicated in drug resistance against tubulin-targeted chemotherapeutics. Our data show the tubulin-targeted anticancer potential of ß-SITO, and its potential clinical utility against ßII and ßIII isotype-overexpressing neoplasms.


Assuntos
Antineoplásicos/química , Multimerização Proteica , Sitosteroides/química , Tubulina (Proteína)/química , Antineoplásicos/metabolismo , Sítios de Ligação , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação Proteica , Domínios Proteicos , Sitosteroides/metabolismo , Tubulina (Proteína)/metabolismo
16.
Steroids ; 117: 38-43, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27648857

RESUMO

Naturally occurring acylated ß-sitosteryl glucosides have been investigated for their novel properties. The synthetic protocol based on the literature data was improved and optimized. The main improvement consists in employing systems of ionic liquids combined with organic solvents in lipase-mediated esterification of (3ß)-stigmast-5-en-3-yl ß-d-glucopyranoside to get (3ß)-stigmast-5-en-3-yl 6-O-acyl-ß-d-glucopyranosides. Maximum yields of these products were achieved with Candida antarctica lipase B immobilized on Immobead 150, recombinant from yeast, in absolute THF and in the presence of either ionic liquid [1-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM]BF4) or 1-butyl-3-methyl imidazolium hexafluorophosphate ([BMIM]PF6)] employed. Pharmacological activity of (3ß)-stigmast-5-en-3-yl 6-O-acyl-ß-d-glucopyranosides was studied in tests on MCF7 tumor cell lines; the compounds displayed moderate activity which was higher than the activity of ß-sitosterol. Supramolecular characteristics were discovered at (3ß)-stigmast-5-en-3-yl 6-O-dodecanoyl-ß-d-glucopyranoside that formed supramolecular polymer through multiple H-bonds in a methanol/water system (60/40). Its formation was confirmed by the independent UV-vis measurements during certain time period, by variable temperature DOSY-NMR measurement in deuteriochloroform, and visualized by transmission electron microscopy (TEM) and atomic force microscopy (AFM) showing chiral helical structures and complex superassembly systems based on fibrous supramolecular polymer. In contrary, no such properties have been observed for the other two (3ß)-stigmast-5-en-3-yl 6-O-acyl-ß-d-glucopyranosides under the given experimental conditions.


Assuntos
Sitosteroides/química , Sitosteroides/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Humanos , Ligação de Hidrogênio , Líquidos Iônicos/química , Lipase/metabolismo , Células MCF-7 , Espectroscopia de Ressonância Magnética , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Sitosteroides/farmacologia
17.
Int J Food Sci Nutr ; 68(1): 52-64, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27575665

RESUMO

Chicories produce a wide range of vegetables with important nutritional value. We determined the variation of sterol, total polyphenol, nitrate contents and antioxidant capacity (SC, TPC, NC, AC) in endive leaves and stem-chicory novel vegetables, cultivated in two Italian regions. Within a given area, the SC was similar in smooth- and curly leafed endives (106.3-176.0 mg/kg FW); sitosterol and stigmasterol were major fractions (45-56 versus 38-43%). The stem SC was independent of landrace (101.5-118.6 mg/kg FW); sitosterol prevailed on stigmasterol and fucosterol (73-76 versus 12-14% versus 8-9%); the latter reached 15.7 mg/kg FW, conferring value as potential antidiabetes food. The planting site affected the AC and TPC of endives (893.1-1571.4 µmTE/100 g FW, 30.8-76.1 GAE100/g FW) and chicory stems (729.8-1152.5 µmTE/100 g FW; 56.2-124.4 GAE100/g FW), while the NC was recurrently below dangerous thresholds. PCA showed that environment was the major cause of variation, though it modestly affected these parameters.


Assuntos
Antioxidantes/análise , Asteraceae/química , Cichorium intybus/química , Produtos Agrícolas/química , Fitosteróis/análise , Folhas de Planta/química , Caules de Planta/química , Antioxidantes/química , Antioxidantes/metabolismo , Asteraceae/crescimento & desenvolvimento , Asteraceae/metabolismo , Cichorium intybus/crescimento & desenvolvimento , Cichorium intybus/metabolismo , Produção Agrícola , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Contaminação de Alimentos , Alimento Funcional/análise , Humanos , Itália , Nitratos/análise , Nitratos/química , Nitratos/metabolismo , Valor Nutritivo , Capacidade de Absorbância de Radicais de Oxigênio , Fenóis/análise , Fenóis/química , Fenóis/metabolismo , Fitosteróis/biossíntese , Fitosteróis/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Análise de Componente Principal , Sitosteroides/análise , Sitosteroides/química , Sitosteroides/metabolismo , Análise Espaço-Temporal , Especificidade da Espécie , Estigmasterol/análogos & derivados , Estigmasterol/análise , Estigmasterol/química , Estigmasterol/metabolismo
18.
Physiol Plant ; 157(2): 120-34, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26671544

RESUMO

Nicotiana benthamiana was used as a model to investigate the spatial and developmental relationship between sterol synthesis rates and sterol content in plants. Stigmasterol levels were approximately twice the level in roots as that found in aerial tissues, while its progenitor sterol sitosterol was the inverse. When incorporation of radiolabeled precursors into sterols was used as measure of in vivo synthesis rates, acetate incorporation was similar across all tissue types, but approximately twofold greater in roots than any other tissue. In contrast, mevalonate incorporation exhibited the greatest differential with the rate of incorporation in roots approximately one-tenth that in apical shoots. Similar to acetate, incorporation of farnesol was higher in roots but remained fairly constant in aerial tissues, suggesting less regulation of the downstream sterol biosynthetic steps. Consistent with the precursor incorporation data, analysis of gene transcript and measurements of putative rate-limiting enzyme activities for 3-hydroxy-3-methylglutaryl-coenzyme A synthase (EC 2.3.3.10) and reductase (EC 1.1.1.34) showed the greatest modulation of levels, while the activity levels for isopentenyl diphosphate isomerase (EC 5.3.3.2) and prenyltransferases (EC 2.5.1.10 and EC 2.5.1.1) also exhibited a strong but moderate correlation with the development age of the aerial tissues of the plants. Overall, the data suggest a multitude of means from transcriptional to posttranslational control affecting sterol biosynthesis and accumulation across an entire plant, and point to some particular control points that might be manipulated using molecular genetic approaches to better probe the role of sterols in plant growth and development.


Assuntos
Nicotiana/metabolismo , Fitosteróis/metabolismo , Sitosteroides/metabolismo , Estigmasterol/metabolismo , Vias Biossintéticas , Ácido Mevalônico/metabolismo , Especificidade de Órgãos , Fitosteróis/química , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Sitosteroides/química , Estigmasterol/química , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento
19.
Biomed Res Int ; 2015: 794718, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26078964

RESUMO

Tetranychus cinnabarinus (Acari: Tetranychidae) is a worldwide polyphagous agricultural pest that has the title of resistance champion among arthropods. We reported previously the identification of the acaricidal compound ß-sitosterol from Mentha piperita and Inula japonica. However, the acaricidal mechanism of ß-sitosterol is unclear. Due to the limited genetic research carried out, we de novo assembled the transcriptome of T. cinnabarinus using Illumina sequencing and conducted a differential expression analysis of control and ß-sitosterol-treated mites. In total, we obtained >5.4 G high-quality bases for each sample with unprecedented sequencing depth and assembled them into 22,941 unigenes. We identified 617 xenobiotic metabolism-related genes involved in detoxification, binding, and transporting of xenobiotics. A highly expanded xenobiotic metabolic system was found in mites. T. cinnabarinus detoxification genes-including carboxyl/cholinesterase and ABC transporter class C-were upregulated after ß-sitosterol treatment. Defense-related proteins, such as Toll-like receptor, legumain, and serine proteases, were also activated. Furthermore, other important genes-such as the chloride channel protein, cytochrome b, carboxypeptidase, peritrophic membrane chitin binding protein, and calphostin-may also play important roles in mites' response to ß-sitosterol. Our results demonstrate that high-throughput-omics tool facilitates identification of xenobiotic metabolism-related genes and illustration of the acaricidal mechanisms of ß-sitosterol.


Assuntos
Proteínas de Insetos/biossíntese , Sitosteroides/metabolismo , Tetranychidae/genética , Transcriptoma/genética , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Insetos/genética , Inseticidas/metabolismo , Inseticidas/farmacologia , Sitosteroides/farmacologia , Tetranychidae/efeitos dos fármacos
20.
Eur J Pharmacol ; 760: 154-62, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25912799

RESUMO

Βeta-sitosterol (ß-SITO), a phytosterol present in pomegranate, peanut, corn oil, almond, and avocado, has been recognized to offer health benefits and potential clinical uses. ß-SITO is orally bioavailable and, as a constituent of edible natural products, is considered to have no undesired side effects. It has also been considered as a potent anticancer agent. However, the molecular mechanism of action of ß-SITO as a tubulin-binding anticancer agent and its binding site on tubulin are poorly understood. Using a combination of biochemical analyses and molecular dynamic simulation, we investigated the molecular details of the binding interactions of ß-SITO with tubulin. A polymer mass assay comparing the effects of ß-SITO and of taxol and vinblastine on tubulin assembly showed that this phytosterol stabilized microtubule assembly in a manner similar to taxol. An 8-anilino-1-naphthalenesulfonic acid assay confirmed the direct interaction of ß-SITO with tubulin. Although ß-SITO did not show direct binding to the colchicine site on tubulin, it stabilized the colchicine binding. Interestingly, no sulfhydryl groups of tubulin were involved in the binding interaction of ß-SITO with tubulin. Based on the results from the biochemical assays, we computationally modeled the binding of ß-SITO with tubulin. Using molecular docking followed by molecular dynamic simulations, we found that ß-SITO binds tubulin at a novel site (which we call the 'SITO site') adjacent to the colchicine and noscapine sites. Our data suggest that ß-SITO is a potent anticancer compound that interferes with microtubule assembly dynamics by binding to a novel site on tubulin.


Assuntos
Antineoplásicos/química , Antineoplásicos/metabolismo , Sitosteroides/química , Sitosteroides/metabolismo , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Sítios de Ligação/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Cabras , Estrutura Secundária de Proteína , Sitosteroides/farmacologia
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