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1.
Artigo em Inglês | MEDLINE | ID: mdl-38544329

RESUMO

Efficient extraction of natural pigments is a key focus in enhancing the utilization of by-products for applications in the food industry. In this study, an enzymatic extraction method using Pectinex Ultra SP-L, Pectinex XXL, Novoshape, and Celluclast was used to investigate natural pigment production from the pomace of aronia, a commercially important plant. The method's performance was monitored using high-performance liquid chromatography with diode-array detection by measuring total and individual anthocyanin levels. Pectinex XXL (0.5%) yielded the highest total anthocyanin extraction (2 082.41 ± 85.69 mg/100 g) in the single enzyme treatment, followed by Pectinex Ultra SP-L (0.05%), Celluclast (0.01%), and Novoshape (0.1%). Combining Pectinex XXL (0.25%) with Celluclast (0.01%) increased the extraction ratio of total anthocyanins (2 323.04 ± 61.32 mg/100 g) by approximately 50.7% compared to that obtained using the solvent extraction method. This study demonstrated an effective enzymatic extraction method for application in the food industry.

2.
Ecotoxicol Environ Saf ; 274: 116227, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38493703

RESUMO

In current study, Fusarium mycotoxin, beauvericin (BEA), has endocrine disrupting potential through suppressing the exogenous androgen receptor (AR)-mediated transcriptional activation. BEA was classified as an AR antagonist, with IC30 and IC50 values indicating that it suppressed AR dimerization in the cytosol. BEA suppress the translocation of cytosolic activated ARs to the nucleus via exogenous androgens. Furthermore, we investigated the impact of environmental conditions for BEA production on rice cereal using response surface methodology. The environmental factors affecting the production of BEA, namely temperature, initial moisture content, and growth time were optimized at 20.28 °C, 42.79 % (w/w), and 17.31 days, respectively. To the best of our knowledge, this is the first report showing that BEA has endocrine disrupting potential through suppressing translocation of cytosolic ARs to nucleus, and temperature, initial moisture content, and growth time are important influencing environmental factors for its biosynthesis in Fusarium strains on cereal.


Assuntos
Depsipeptídeos , Fusarium , Micotoxinas , Oryza , Receptores Androgênicos , Humanos , Depsipeptídeos/toxicidade , Grão Comestível/química , Fusarium/metabolismo , Micotoxinas/toxicidade , Oryza/química , Receptores Androgênicos/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Disruptores Endócrinos/química , Disruptores Endócrinos/toxicidade
3.
J Hazard Mater ; 469: 133935, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38442602

RESUMO

Bisphenol A (BPA) and its various forms used as BPA alternatives in industries are recognized toxic compounds and antiandrogenic endocrine disruptors. These chemicals are widespread in the environment and frequently detected in biological samples. Concerns exist about their impact on hormones, disrupting natural biological processes in humans, together with their negative impacts on the environment and biotic life. This study aims to characterize the interaction between BPA analogs and the androgen receptor (AR) and the effect on the receptor's normal activity. To achieve this goal, molecular docking was conducted with BPA and its analogs and dihydrotestosterone (DHT) as a reference ligand. Four BPA analogs exhibited higher affinity (-10.2 to -8.7 kcal/mol) for AR compared to BPA (-8.6 kcal/mol), displaying distinct interaction patterns. Interestingly, DHT (-11.0 kcal/mol) shared a binding pattern with BPA. ADMET analysis of the top 10 compounds, followed by molecular dynamics simulations, revealed toxicity and dynamic behavior. Experimental studies demonstrated that only BPA disrupts DHT-induced AR dimerization, thereby affecting AR's function due to its binding nature. This similarity to DHT was observed during computational analysis. These findings emphasize the importance of targeted strategies to mitigate BPA toxicity, offering crucial insights for interventions in human health and environmental well-being.


Assuntos
Disruptores Endócrinos , Receptores Androgênicos , Humanos , Receptores Androgênicos/metabolismo , Disruptores Endócrinos/metabolismo , Simulação de Acoplamento Molecular , Fenóis/metabolismo , Di-Hidrotestosterona/farmacologia , Compostos Benzidrílicos/toxicidade , Compostos Benzidrílicos/metabolismo
4.
Food Sci Biotechnol ; 33(5): 1255-1260, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38440673

RESUMO

This study explored the temperature-dependent effect on the growth characteristics of Salmonella Enteritidis (SE) on eggshell toward identifying an appropriate storage temperature for unwashed eggs in an actual distribution environment. Among the test storage temperatures (10 °C, 25 °C, and 35 °C), 25 °C was determined to be an appropriate storage temperature, with no effect of changing temperature on the control of SE on eggshell. Regarding the effect of the temperature on egg quality, the quality indicators of egg such as Haugh unit, yolk index, albumin index, and albumin pH were significantly maintained. These results indicated that unwashed eggs should be distributed at 25 °C for SE control, and the storage temperature should be below 10 °C from at least day 4 onward after the start of distribution to maintain egg quality. This study will assist for safety management of unwashed egg in an actual distribution environment.

5.
Pestic Biochem Physiol ; 199: 105757, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458660

RESUMO

Fenhexamid are fungicides that act against plant pathogens by inhibiting sterol biosynthesis. Nonetheless, it can trigger endocrine disruption and promote breast cancer cell growth. In a recent study, we investigated the mechanism underlying the lipid accumulation induced by fenhexamid hydroxyanilide fungicides in 3 T3-L1 adipocytes. To examine the estrogen receptor alpha (ERα)-agonistic effect, ER transactivation assay using the ERα-HeLa-9903 cell line was applied, and fenhexamid-induced ERα agonist effect was confirmed. Further confirmation that ERα-dependent lipid accumulation occurred was provided by treating 3 T3-L1 adipocytes with Methyl-piperidino-pyrazole hydrate (MPP), an ERα-selective antagonist. Fenhexamid mimicked the actions of ERα agonists and impacted lipid metabolism, and its mechanism involves upregulation of the expression of transcription factors that facilitate adipogenesis and lipogenesis. Additionally, it stimulated the expression of peroxisome proliferator-activated receptor (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), fatty acid synthase (FAS), and sterol regulatory element-binding protein 1 (SREBP1) and significantly elevated the expression of fatty acid-binding protein 4 (FABP4). In contrast, in combination with an ERα-selective antagonist, fenhexamid suppressed the expression of adipogenic/lipogenic transcription factors. These results suggest that fenhexamid affects the endocrine system and leads to lipid accumulation by interfering with processes influenced by ERα activation.


Assuntos
Amidas , Receptor alfa de Estrogênio , Fungicidas Industriais , Camundongos , Animais , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Fungicidas Industriais/toxicidade , Fungicidas Industriais/metabolismo , Adipócitos/metabolismo , Adipogenia , Metabolismo dos Lipídeos , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/farmacologia , Lipídeos , Células 3T3-L1 , PPAR gama/metabolismo
6.
J Steroid Biochem Mol Biol ; 239: 106483, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38369033

RESUMO

Beauvericin (BEA) is a cyclic depsipeptide secondary metabolite of Fusarium species. It causes chemical hazards in food products and exists in an environment containing soil and various food types. On the other hand, the purified BEA has various biological activities and is regarded as a potential candidate for pharmaceutical research. This study was performed to assess the anti-proliferation activity of BEA against human breast cancer cells by regulating the estrogen receptor-alpha (ERα)/p38 pathway. TA and BA assays verified that BEA is a completed ER antagonist. Additionally, BEA suppressed cell proliferation in the anti-proliferation assay involving ER-positive human breast cancer cells co-treated with BPA and BEA. In respect to an anti-proliferation activity, the BPA-induced phosphorylation of p38 protein was inhibited in the presence of BEA. These results suggested that BEA exerts inhibitory potentials on endocrine disrupting effect and possibly acts as a natural therapeutic material for human estrogen hormonal health.


Assuntos
Compostos Benzidrílicos , Neoplasias da Mama , Depsipeptídeos , Fusarium , Fenóis , Humanos , Feminino , Receptor alfa de Estrogênio/metabolismo , Fusarium/metabolismo , Neoplasias da Mama/tratamento farmacológico , Depsipeptídeos/farmacologia , Depsipeptídeos/metabolismo , Proliferação de Células , Linhagem Celular , Linhagem Celular Tumoral
7.
Food Sci Biotechnol ; 33(3): 579-587, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38274188

RESUMO

The environmental conditions were optimized to produce the enniatin H, I, and MK1688 by Fusarium strain on cereal grain exhibiting anti-carcinogenic potential against MES-SA (human uterine sarcoma cell line), HCT15 (human colorectal carcinoma cancer cell line), and their multidrug resistance sublines. From the statistical optimization by response surface methodology, the optimal condition of independent variables affecting the response variables were 20.85 °C (temperature), 46.85% (w/w, initial moisture content), and 18.42 days (growth time) for ENN H; 23.31 °C, 44.15% (w/w) and 17.23 days for ENN I; 23.08 °C, 43.97% (w/w) and 17.06 days for ENN MK1688. In case of cytotoxic effects, ENNs significantly suppressed growth of cancer cell lines without multidrug resistance, and ENN I inhibited growth of cancer cell lines most strongly. These data will provide valuable point to produce the cyclic hexadepsipeptide exhibiting anti-carcinogenic potential from Fusarium strains.

8.
Sci Total Environ ; 898: 165472, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37442466

RESUMO

Aquaculture farms have been established along the South Sea Coast of Korea, supplying most of the seafood consumed domestically. However, annual harmful algal blooms pose a potential threat to seafood safety. This study aimed to determine the spatial and seasonal distributions of 12 lipophilic marine biotoxins (LMTs) in phytoplankton and mussels in the region in 2021. Solid-phase adsorption toxin tracking (SPATT) was used to monitor the cumulative compositions of LMTs in seawater. LMT concentrations were also determined in twelve commercially available species of domestic shellfish to evaluate the potential risks to human health. Gonyaulux spinifera and Dinophysis acuminata, causative microalgae of yessotoxins (YTXs) and pectenotoxins (PTXs), respectively, showed high densities in the region from May to July. This period corresponded to high LMT concentrations in phytoplankton and mussels. Phytoplankton mainly contained PTX-2 and homo-YTX, with a maximum concentration of 2300 ng g-1 wet weight (ww) in May. In contrast, mussels mainly contained homo-YTX and YTX, with a maximum concentration of 1300 ng g-1 ww in July. LMTs-producing microalgae showed low densities and concentrations after July, whereas mussels accumulated toxins until September. In the SPATT sampler, more diverse LMTs were detected than in seawater, phytoplankton, and mussels. For example, dinophysistoxin-1 and azaspiracid-2 were detected only in SPATT. YTXs were detected in domestic seafood samples, including mussels, red scallops, and pen shells, but the concentrations were below the European Food Safety Agency recommended standard of 3.75 mg YTX-eq. kg-1. Moreover, the hazard quotient was less than 100 in all scenarios, indicating that the human health risk was not significant. This study provides valuable data on monthly distribution patterns of LMTs in the South Sea Coast of Korea and can serve as baseline data for future management policies of marine biotoxins.


Assuntos
Bivalves , Dinoflagelados , Microalgas , Animais , Humanos , Toxinas Marinhas , Frutos do Mar/análise , Fitoplâncton , Saxitoxina , República da Coreia
9.
J Med Food ; 26(7): 480-488, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37463401

RESUMO

The maintenance of bone is dependent on both osteoclasts, which break down bone, and osteoblasts, which build new bone. Various bone-related disorders, including osteoporosis, can occur as a result of an imbalance between these two cell types. Prolonged use of currently available bone resorption inhibitors may show side effects. Therefore, developing a novel preventive material which effectively inhibits osteoclast differentiation could be beneficial. This study planned to investigate the inhibitory effect of wheat sprout ethanolic extracts (Saegeumgang [SGG] and Arriheuk [ARH]) on the differentiation of osteoclasts induced by RANKL, as well as the mechanisms why fundamental to these effects. The effects of SGG and ARH on bone resorption and osteoclast differentiation were evaluated using RAW 264.7 cells and assessed through TRAP cell count, pit formation, and activity. The expressions of mRNA and protein were accomplished using western blotting, and reverse transcription quantitative polymerase chain reaction analyses were conducted. SGG and ARH were found to suppress osteoclast differentiation in RANKL-stimulated RAW264.7 cells without causing cytotoxic effects. In addition, treatment with SGG and ARH led to a reduction in the number of cells with positive staining for TRAP and TRAP activity. SGG and ARH treatment dose-dependently decreased the pit area in pit formation assays, showing a notable reduction compared to the pit area created by mature osteoclasts. SGG and ARH inhibited osteoclast activity by 84.9% and 95.7% at 200 µg/mL, respectively. In addition, SGG and ARH suppressed the transcriptional activation of various osteoclast-related genes, such as RANK, NFATc1, cathepsin K, c-Fos, TRAP, matrix metallopeptidase-9, dendritic cell-specific transmembrane protein, ATPase H+ transporting v0 subunit d2, and osteoclast-associated receptor in RAW264.7 cells treated with RANKL. SGG and ARH extracts were found to affect the expression of NFATc1 and genes that are specific to osteoclasts during osteoclast differentiation, suggesting their potential use as functional foods or as therapeutic interventions targeting bone health.


Assuntos
Reabsorção Óssea , Osteoclastos , Triticum/metabolismo , Fatores de Transcrição , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/metabolismo , Transdução de Sinais , Diferenciação Celular , Ligante RANK/metabolismo
10.
Chem Biol Interact ; 378: 110489, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37059213

RESUMO

We assessed the mechanism of human androgen receptor-mediated endocrine-disrupting effect by a triazole fungicide, metconazole in this study. The internationally validated stably transfected transactivation (STTA) in vitro assay, which was established for determination of a human androgen receptor (AR) agonist/antagonist by using 22Rv1/MMTV_GR-KO cell line, alongside an in vitro reporter-gene assay to confirm AR homodimerization was used. The STTA in vitro assay results showed that metconazole is a true AR antagonist. Furthermore, the results from the in vitro reporter-gene assay and western blotting showed that metconazole blocks the nuclear transfer of cytoplasmic AR proteins by suppressing the homodimerization of AR. These results suggest that metconazole can be considered to have an AR-mediated endocrine-disrupting effect. Additionally, the evidence from this study might help identify the endocrine-disrupting mechanism of triazole fungicides containing a phenyl ring.


Assuntos
Androgênios , Fungicidas Industriais , Humanos , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Ativação Transcricional , Fungicidas Industriais/toxicidade , Triazóis/farmacologia , Antagonistas de Androgênios/farmacologia , Antagonistas de Receptores de Andrógenos/farmacologia
11.
Environ Pollut ; 325: 121437, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36907237

RESUMO

This study was carried out to provide the evidence with respect to the adverse potential of chlorpropham, a representative carbamate ester herbicide product, on the endocrine system by using in vitro testing methods in accordance with the Organization for Economic Cooperation and Development Test Guideline No. 458 (22Rv1/MMTV_GR-KO human androgen receptor [AR] transcriptional activation assay) and a bioluminescence resonance energy transfer-based AR homodimerization assay. Results revealed that chlorpropham had no AR agonistic effects, but it was determined to be a true AR antagonist without intrinsic toxicity against the applied cell lines. In the mechanism of chlorpropham-induced AR-mediated adverse effects, chlorpropham suppressed cytoplasmic AR translocation to the nucleus by inhibiting the homodimerization of the activated ARs. This suggests that chlorpropham exposure caused endocrine-disrupting effects through its interactions with human AR. Additionally, this study might help identify the genomic pathway of the AR-mediated endocrine-disrupting potential of N-phenyl carbamate herbicides.


Assuntos
Clorprofam , Herbicidas , Humanos , Clorprofam/metabolismo , Clorprofam/toxicidade , Herbicidas/toxicidade , Herbicidas/metabolismo , Receptores Androgênicos , Androgênios , Carbamatos/toxicidade , Sistema Endócrino
12.
Phytother Res ; 37(7): 3069-3082, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36877124

RESUMO

This study was conducted to investigate the effect of Gynostemma pentaphyllum extract containing gypenoside L (GPE) on improving the cognitive aspects of fatigue and performance of the motor system. One hundred healthy Korean adults aged 19-60 years were randomized to the treatment (GPE for 12 weeks) and control groups, and efficacy and safety-related parameters were compared between the two groups. Maximal oxygen consumption (VO2 max) and O2 pulse were significantly higher in the treatment group than in the control group (p = 0.007 and p = 0.047, respectively). After 12 weeks, the treatment group showed significant changes such as decreases in the levels of free fatty acids (p = 0.042). In addition, there were significant differences in the rating of perceived exertion (RPE) (p < 0.05) and value of temporal fatigue between the treatment and control groups on the multidimensional fatigue scale (p < 0.05). Moreover, the level of endothelial nitric oxide synthase (eNOS) in the blood was significantly higher in the treatment group than in the control group (p = 0.047). In summary, oral administration of GPE has a positive effect on resistance to exercise-induced physical and mental fatigue.


Assuntos
Gynostemma , Extratos Vegetais , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
13.
Environ Pollut ; 318: 120894, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36549450

RESUMO

We selected azole pesticides products that are managed by setting maximum residue limits (MRLs) in the Republic of Korea and describe the estrogen receptor (ER) α-related negative effect to endocrine system using in vitro Organization for Economic Cooperation and Development performance-based test guideline. No azoles were found to be an ERα agonist. Conversely, three azoles (bitertanol, cafenstrole, and tebufenpyrad) were determined to be ERα antagonists. In addition, the ERα antagonistic activities of bitertanol, cafenstrole, and tebufenpyrad were not significantly perturbed in the existence of phase I (hydroxylation, dealkylation, oxidation or reduction) and phase II (conjugation). Regarding the mechanism underlying their ERα-mediated endocrine disrupting potentials, ERα proteins cannot be translocated to the nucleus by suppressing the dimerization of ERα in the cytoplasm by bitertanol, cafenstrole, and tebufenpyrad. These data indicated that azole pesticide products show the capability to interfere the ERα-related human endocrine system. Furthermore, we identified the mechanism of ERα-mediated endocrine disrupting by azole insecticide products through this study.


Assuntos
Receptor alfa de Estrogênio , Praguicidas , Humanos , Receptor alfa de Estrogênio/metabolismo , Dimerização , Azóis/toxicidade , Receptores de Estrogênio/metabolismo , Sistema Endócrino , Receptor beta de Estrogênio/metabolismo
14.
Ecotoxicol Environ Saf ; 247: 114246, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36332405

RESUMO

Several pesticides widely used in agriculture have been considered to be endocrine disrupting chemicals through their binding affinities to estrogen or androgen receptors. This study was conducted to clarify the human androgen receptor (hAR)-mediated genomic endocrine disrupting mechanism of eight selected pesticide products by in vitro assay providing the Organization for Economic Co-operation and Development Test Guideline No. 458, 22Rv1/MMTV_GR-KO AR transcriptional activation assay and a homo-dimerization confirmation assay. None of the tested pesticide products showed an AR agonistic effect, whereas they were all determined to be AR antagonists at non-toxic concentrations. Also, the eight pesticide products were verified as true AR antagonists through a specificity control test. In the Bioluminescence Resonance Energy Transfer-based AR homo-dimerization confirmation assay, the eight pesticide products did not induce AR homo-dimerization. Additionally, western blotting revealed that none of the eight pesticide products induced AR translocation from the cytoplasm to the nucleus. In conclusion, we found for the first-time evidence to understand the AR-mediated endocrine disrupting mechanisms induced by selected azole and organophosphorus pesticide products.


Assuntos
Praguicidas , Receptores Androgênicos , Humanos , Receptores Androgênicos/genética , Dimerização , Compostos Organofosforados/toxicidade , Azóis , Praguicidas/toxicidade , Genômica
15.
Food Sci Biotechnol ; 31(7): 797-805, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35720465

RESUMO

Polyvinyl alcohol (PVOH) is extensively used in agricultural, pharmaceutical, textile, and food industries. A new high-performance liquid chromatography (HPLC) method with evaporative light scattering detection (ELSD) was developed for the quantitative analysis of PVOH products. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was employed for method verification. The HPLC-ELSD method exhibited acceptable linearity (R2 > 0.99), with limits of detection and quantitation of 19.43 and 58.88 µg/mL, respectively. Accuracies of 91.16-102.30% were estimated based on recoveries of the intra- and inter-day tests of PVOH. Repeatability and intermediate precision (%RSD) of 1.23-4.45 and 2.18-6.95, respectively, were obtained. The presence of PVOH in the HPLC peaks was further verified using typical indicators of PVOH in Py-GC/MS analysis, such as acetaldehyde, 2,5-dihydrofuran, benzaldehyde, and crotonaldehyde. This novel HPLC method with Py-GC/MS-based verification can be successfully applied for analyzing PVOH in dietary supplement tablets.

16.
Mar Pollut Bull ; 180: 113776, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35635885

RESUMO

The distribution characteristics of lipophilic marine biotoxins (LMTs), such as yessotoxins (YTXs) and pectenotoxins (PTXs) in phytoplankton, mussels, and commercial seafood were determined for the southern coast of South Korea. Gonyaulax spinifera and Dinophysis acuminata, which are the causative microalgae of YTXs and PTXs, were recorded during summer. Homo-YTX and PTX-2 were predominantly detected in phytoplankton (max: 5.7 µg g-1 ww), whereas only YTXs were detected in mussels (max: 1.1 µg g-1 ww). LMT concentrations in mussels were positively correlated with those in phytoplankton. However, there was a 1-month time gap in maximum LMT concentrations between mussels and phytoplankton. Homo-YTX was detected in commercial seafood, including red scallop and comb pen shell. However, homo-YTX concentrations in shellfish were below the recommended value of the European Food Safety Authority (3.75 mg YTX equivalents kg-1); thus, the consumption of this seafood was not considered to be a significant risk for human health.


Assuntos
Bivalves , Dinoflagelados , Animais , Cromatografia Líquida , Humanos , Venenos de Moluscos , Oxocinas , Fitoplâncton , Alimentos Marinhos/análise , Frutos do Mar/análise
17.
Toxicol Appl Pharmacol ; 434: 115815, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34848279

RESUMO

With growing scientific interest in phytoestrogens, a number of studies have investigated the estrogenic potential of phytoestrogens in a wide variety of assay systems. However, evaluations of individual phytoestrogens with different assay systems make it difficult for predicting their relative estrogenic potency. The objective of this study was to compare estrogenic properties of fifteen known phytoestrogens using an estrogen receptor-α (ER-α) dimerization assay and Organization for Economic Cooperation and Development (OECD) standardized methods including in vitro estrogen receptor (ER) transactivation assay using VM7Luc4E2 cells and in vivo uterotrophic assay using an immature rat model. Human ER-α dimerization assay showed positive responses of eight test compounds and negative responses of seven compounds. These results were consistently found in luciferase reporter assay results for evaluating ER transactivation ability. Seven test compounds exhibiting relatively higher in vitro estrogenic activities were subjected to uterotrophic bioassays. Significant increases in uterine weights were only found after treatments with biochanin A, 8-prenylnaringenin, and coumestrol. Importantly, their uterotrophic effects were lost when animals were co-treated with antagonist of ER, indicating their ER-dependent effects in the uterus. In addition, analysis of estrogen responsive genes revealed that these phytoestrogens regulated uterine gene expressions differently compared to estrogens. Test methods used in this study provided a high consistency between in vitro and in vivo results. Thus, they could be used as effective screening tools for phytoestrogens, particularly focusing on their interactions with ER-α.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Organização para a Cooperação e Desenvolvimento Econômico/normas , Fitoestrógenos/farmacologia , Animais , Regulação para Baixo , Receptor alfa de Estrogênio/antagonistas & inibidores , Feminino , Fulvestranto/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Ratos , Ratos Wistar , Útero/efeitos dos fármacos , Útero/metabolismo
18.
Chemosphere ; 290: 133267, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34914963

RESUMO

The adverse outcome pathway (AOP) has been recently proposed as an effective framework for chemical risk assessment. The AOP framework offers the advantage of effectively integrating individual in vitro studies and in silico prediction models. Thus, the development of an effective testing method to measure key events caused by chemicals is essential for chemical risk assessment through a fully developed AOP framework. We developed a human cell-based estrogen receptor α (ERα) dimerization assay using the bioluminescence resonance energy transfer (BRET) technique and evaluated the ERα dimerization activities of 72 chemicals. Fifty-one chemicals were identified to mediate dimerization of ERα, and the BRET-based ERα dimerization assay could effectively measure the events that mediated dimerization of ERα by the estrogenic chemicals. These results were compared with the results of pre-existing assay to determine whether the BRET-based ERα dimerization assay could be employed as an in vitro test method to provide scientific information for explaining key events as a part of the AOP framework. Consequently, we propose that the BRET-based ERα dimerization assay is suitable for measuring the chemical-mediated dimerization of ERα, a key event in the AOP framework for cellular-level risk assessment of estrogenic chemicals.


Assuntos
Rotas de Resultados Adversos , Disruptores Endócrinos , Dimerização , Disruptores Endócrinos/toxicidade , Transferência de Energia , Receptor alfa de Estrogênio/metabolismo , Humanos
19.
J Med Food ; 24(12): 1285-1292, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34939859

RESUMO

A number of studies employing different in vitro assays have demonstrated the estrogen-like activity of natural substances. All assays have their advantages and limitations as a screening tool. No single in vitro assay is considered ideal for predicting estrogenic action in a complex in vivo system. To assess agonistic activities of several medicinal herbs on the estrogen receptor (ER) and their metabolic alteration, the Organization for Economic Cooperation and Development (OECD) Performance-Based Test Guideline No. 455 in vitro assay was performed in this study using recombinant VM7Luc4E2 cells in combination with rat liver S9 fractions. Ethanol extracts of medicinal herbs showed binding affinities for ER-α and ER-ß at different levels. However, luciferase reporter assay using VM7Luc4E2 cells revealed that only two test extracts [Pueraria lobata root extract (PLE); Glycyrrhiza glabra root extract (GGE)] exhibited ER transcriptional activity when their activities were compared with the response by 17ß-estradiol. Importantly, incubation of PLE or GGE with rat liver S9 fractions increased their ER transcriptional activities, in particular when phase I metabolic enzymes were activated. Puerarin and glabridin were the most abundant isoflavones found in PLE and GGE, respectively. The present results demonstrate that PLE and GGE possess potential as ER agonists with their metabolic activation. This study also suggests that the application of OECD in vitro assay with rat liver S9 fraction is an efficient screening tool to evaluate estrogenic activities of natural substances.


Assuntos
Plantas Medicinais , Receptores de Estrogênio , Animais , Estrogênios , Fígado/metabolismo , Organização para a Cooperação e Desenvolvimento Econômico , Ratos , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Ativação Transcricional
20.
Enzyme Microb Technol ; 151: 109918, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34649693

RESUMO

As the only glycoside hydrolase family 48 member in Clostridium thermocellum, the exoglucanase Cel48S plays a crucial role in the extremely high activity of the cellulosome against crystalline cellulose. Although the importance of Cel48S in the hydrolysis of crystalline cellulose has been widely accepted, an efficient production system has not yet been established because Cel48S is usually expressed in Escherichia coli within inactive inclusion bodies. For unstable proteins like Cel48S, translocation across the inner membrane can be more advantageous than cytoplasmic production due to the presence of folding modulators in the periplasm and the absence of cytoplasmic proteases. In this study, we evaluated whether the production of Cel48S in the periplasmic space of E. coli could enhance its functional expression. To do so, we attached the PelB signal peptide, which mediates post-translational secretion, to the N-terminal end of Cel48S (P-Cel48S). The PelB signal peptide allowed catalytically active Cel48S to be successfully produced in the culture medium. In addition, we investigated the role of an alternative co-translational pathway on the extracellular production of Cel48S, finding that co-translational secretion yielded a specific activity of recombinant Cel48S of 135.1 ± 10.0 U/mg cell in the culture medium, which was 2.2 times higher than that associated with P-Cel48S expression. Therefore, we believe that our approach has potential applications for the cost-effective conversion of lignocellulosic biomass and the industrial production of other unstable proteins.


Assuntos
Celulase , Clostridium thermocellum , Celulase/genética , Celulase/metabolismo , Clostridium thermocellum/genética , Clostridium thermocellum/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Periplasma/metabolismo , Partícula de Reconhecimento de Sinal
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