RESUMO
Although interest in stabilized α-helical peptides as next-generation therapeutics for modulating biomolecular interfaces is increasing, peptides have limited functionality and stability due to their small size. In comparison, α-helical ligands based on proteins can make steric clash with targets due to their large size. Here, we report the design of a monomeric pseudo-isolated α-helix (mPIH) system in which proteins behave as if they are peptides. The designed proteins contain α-helix ligands that do not require any covalent chemical modification, do not have frayed ends, and importantly can make sterically favorable interactions similar to isolated peptides. An optimal mPIH showed a more than 100-fold increase in target selectivity, which might be related to the advantages in conformational selection due to the absence of frayed ends. The α-helical ligand in the mPIH displayed high thermal stability well above human body temperature and showed reversible and rapid folding/unfolding transitions. Thus, mPIH can become a promising protein-based platform for developing stabilized α-helix pharmaceuticals.
Assuntos
Peptídeos , Proteínas , Sequência de Aminoácidos , Dicroísmo Circular , Humanos , Peptídeos/química , Conformação Proteica em alfa-Hélice , Dobramento de Proteína , Estrutura Secundária de ProteínaRESUMO
Chrysin is a flavonoid found abundantly in substances, such as honey and phytochemicals, and is known to exhibit anticancer effects against various cancer cells. Nevertheless, the anticancer effect of chrysin against oral cancer has not yet been verified. Furthermore, the mechanism underlying autophagy is yet to be clearly elucidated. Thus, this study investigated chrysin-mediated apoptosis and autophagy in human mucoepidermoid carcinoma (MC-3) cells. The change in MC-3 cell viability was examined using a 3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide cell viability assay, as well as 40,6-diamidino-2-phenylindole, annexin V, and propidium iodide staining. Western blotting was used to analyze the proteins related to apoptosis and the mitogen-activated protein kinase (MAPK) pathway. In addition, the presence or absence of autophagy and changes in the expression of related proteins were investigated using acridine orange staining and Western blot. The results suggested that chrysin induced apoptosis and autophagy in MC-3 oral cancer cells via the MAPK/extracellular signal-regulated kinase pathway. Moreover, the induced autophagy exerted a cytoprotective effect against apoptosis. Thus, the further reduced cell viability due to autophagy as well as apoptosis induction highlight therapeutic potential of chrysin for oral cancer.
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Apoptose , Neoplasias Bucais , Humanos , Serina-Treonina Quinases TOR/metabolismo , Flavonoides/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Autofagia , Linhagem Celular Tumoral , Neoplasias Bucais/tratamento farmacológicoRESUMO
This study aimed to estimate the dietary taurine intake and its food sources in Korean's aged between 19 and 29 years. The study included 619 participants (292 males and 327 females) who had provided data via a 24-h recall method to the 2015 Korea National Health and Nutrition Examination Survey (KNHANES). Dietary taurine intake and the sources of dietary taurine were estimated by using CAN-Pro 4.0 software. Statistical analysis was performed by using SPSS 20.0. Average height and weight of the subjects was 174 cm and 73.5 kg in males and 161 cm and 56.4 kg in females, respectively. The prevalence of obesity in males was significantly higher compared to females (p < 0.001). Overall, the nutrient intakes of subjects were higher than the dietary reference intakes for Korean's (KDRIs). In particular, phosphorus and sodium intakes of males and females were higher, whereas, potassium and calcium intakes of males and females were lower than the KDRIs. The average intake of taurine 327.3 mg by males was significantly higher compared to 245.1 mg by females (p < 0.05). With regard to dietary taurine intake from the main food groups, meat (p < 0.001), vegetable (p < 0.001), beverages and alcohol (p < 0.05), and cereal (p < 0.001), in males was significantly higher compared to females. This study showed that 19-29 years old Korean young adults had a high intake of taurine due to high intake of protein. However, since high intake of meat can lead to chronic disease, it is necessary to provide nutrition education to increase the intake of fishes and shellfishes as a taurine source food.
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Dieta , Inquéritos Nutricionais , Taurina/administração & dosagem , Adulto , Feminino , Alimentos , Humanos , Masculino , República da Coreia , Adulto JovemRESUMO
The purpose of this research is to investigate the effects of dietary taurine supplementation on blood and urine taurine concentrations of the elderly women with dementia. Subjects were 31 female elderly with dementia hospitalized in a geriatric hospital. They were divided randomly into control group and dietary taurine supplemented group. Basically, same meals were served to both groups. Scorched rice water without taurine were served to control group. Scorched rice water containing 3 g of taurine were reserved to taurine group with lunch similarly. Food ingredients containing high concentration of taurine were eliminated from the meal menu. Blood and urine samples were obtained from each subject at the beginning of study, after 2 week and 4 weeks in the morning fasting state. Taurine concentrations in serum and urine were measured as taurine-fluorescamine derivatives using high performance liquid chromatography (HPLC). Data were analyzed using SPSS 20.0. The average taurine concentrations in serum and urine of subjects were 89.2 ± 9.5 µM and 876.7 ± 97.1 µM at the beginning. After 4 weeks, the taurine concentrations in serum and urine of dietary taurine supplemented group were 218.0 ± 15.6 µM and 6502.6 ± 380.6 µM, which were significantly higher compared to control group. Dietary taurine supplemented group showed positive changes in the score on language and execute performance. So taurine supplementation can provide beneficial effects to the elderly and the elderly with dementia.
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Demência/sangue , Demência/urina , Suplementos Nutricionais , Taurina/administração & dosagem , Idoso , Feminino , Humanos , Taurina/sangue , Taurina/urinaRESUMO
The purpose of this study was to investigate food preference of the elderly for the development of taurine-containing elderly-friendly foods (TEF). The subjects in this study were 278 elderly people who were over 65 years old. All data were collected by face to face interview. Statistical analysis was performed by using SPSS 20.0 for Windows. The 'low-salt diet', 'nutritional enriched diet', and 'swallow able diet' were diets that all subjects preferred. All subjects preferred a diet to be sold as three items in separate packaging, as a semi-cooked type. The food types and cooking methods that showed high preference and had a high intention to purchase were cooked rice, porridges, soups and stews, meat side dishes, fish side dishes, kimchi, and vegetable dishes and steaming Among the taurine-containing foods, whip-arm octopus, manila clam, dried anchovy, flatfish, pollack, laver, green laver, sea tangle, seaweed, cod, croaker, and cutlassfish were the preferred foods of most subjects. Elderly females preferred significantly more squid, octopus, eel, mudfish, and sea cucumber than that of elderly males (p < 0.05). Elderly males preferred and consumed significantly more taurine-supplement than did elderly females (p < 0.05). These results will be used as baseline data for development of a customized TEF for Korean elderly.
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Dieta , Preferências Alimentares , Taurina/administração & dosagem , Idoso , Culinária , Feminino , Humanos , Masculino , República da Coreia , Alimentos Marinhos , VerdurasRESUMO
The purpose of this study was to investigate the correlations among taurine-related nutritional knowledge (TNK), taurine intake frequency (TIF), and cognitive function (CF) in Korean elderly. Subjects of this cross-sectional study were 278 elderly persons in Korea without dementia (men 76, women 202). The subjects were divided into two groups: a group with a lower than average TNK score (LAG) and a group with a higher than average TNK score (HAG). Data were obtained via questionnaires and 1: 1 interviews. Correlation analysis available in SPSS 20.0 was used to analyze associations among the three factors. Average TNK score of all subjects was 4 out of 10 points, while that of the LAG (1.9 points) was significantly lower than that of the HAG (6.6 points) (p < 0.001). Average TIF score in the HAG (195.3 points) was significantly higher than that of the LAG (180.8 points) (p < 0.001). Compared to the LAG, the HAG members more frequently consumed foods such as webfoot octopus, whelk, dried anchovy, dried shrimp, mackerel, anglerfish, skate, short-necked clam, shrimp, and dried squid (p < 0.01). There was no significant difference in CF scores between the LAG and HAG. There was positive correlation between TNK and TIF scores in all the subjects (p < 0.01). There was no significant difference, but there was a tendency for a positive correlation, between TNK and CF scores (p = 0.072). These results suggest that nutritional education of the elderly about taurine is needed, and it is strongly recommended that the elderly frequently consume taurine-containing foods and supplements to prevent dementia.
Assuntos
Cognição , Dieta , Conhecimentos, Atitudes e Prática em Saúde , Taurina/administração & dosagem , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , República da Coreia , Alimentos MarinhosRESUMO
The purpose of this study was to investigate consumption patterns and perform Importance-Performance Analysis (IPA) of selective attributes of Home Meal Replacement (HMR) products according to taurine-related nutritional knowledge levels in Koreans aged 40-64 years as a basis for developing additional HMR products. The study included 793 adults (297 males and 496 females) who had experience in consuming HMR products and who lived in Seoul and its metropolitan areas, Korea. Data were collected using self-administered questionnaires. Statistical analysis was performed by using the SPSS 18.0 program. The subjects were classified into a high-level group (HG, 467 adults) and low-level group (LG, 326 adults) based on their taurine-related nutritional knowledge scores. Analysis of HMR consumption patterns showed that the frequency of HMR consumption in the HG was one to two times a month in 41.1% of the subjects and once every 3-4 months in 22.7% of the subjects, whereas, in the LG, it was one to two times a month in 39.3% of the subjects and four to six times a month in 24.5% of the subjects. With regarding to the reasons for purchasing HMR products, there was no significant difference between HG and LG (p = 0.089). The IPA analysis of HMR selective attributes included factor analysis of 14 selective attributes that were divided into three factors: 'convenience and taste', 'reliability and health', and 'brand and awareness'. The average importance scores of the first (p < 0.01), second (p < 0.001), and third (p < 0.01) factors in the HG were significantly higher than those in the LG. In addition, the average satisfaction with the first factor (p < 0.01) in the HG was significantly higher than that in the LG. Based on the IPA results, the selective attributes with low satisfaction and high importance were price, origin, food additives, and nutrient content in both the HG and LG. In the second IPA quadrant was safety, but only in the LG. Multiple regression analysis revealed that the importance of the reliability and health factor and the satisfaction with the convenience and taste factor were positively influenced by the subject's taurine-related nutritional knowledge score. These results suggest that reliability and safety of HMR products need to be improved to meet the expectations of Korean consumers aged 40 years and older with a high level of taurine-related nutritional knowledge. Therefore, there is a need to produce HMR products that use safe and reliable food ingredients.
Assuntos
Alimentos Fortificados , Conhecimentos, Atitudes e Prática em Saúde , Taurina/administração & dosagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , República da Coreia , Inquéritos e Questionários , PaladarRESUMO
It has been reported that taurine intake in the past may have a positive effect on present cognitive function in the elderly. The purpose of this cross-sectional study was to investigate the need to develop an elderly-friendly home meal replacement (EF-HMR) containing taurine for the prevention of dementia in Korean adults aged 40-84 years. Study subjects included 481 adults 40-49 years group, 319 adults 50-64 years group, and 181 elderly group (65-84 years old) residing in Seoul and its metropolitan area, Korea. Data were collected from adults aged 40-64 years by self-administered questionnaires and from elderly through face-to-face interviews. Statistical analysis was performed using SPSS 18.0. The level of need for EF-HMR was significantly higher in 40-49 years and 50-64 years groups compared to the elderly group (p < 0.001). With regard to the preferred EF-HMR taste, the needs for less salty (p < 0.01) and less sweet (p < 0.001) foods were significantly higher in 40-49 years group compared to the elderly group. The main factors of consideration in the development of EF-HMR were nutrition, taste, and freshness. The level of need for EF-HMR containing taurine was significantly lower in those 40-49 years and 50-64 years groups compared to the elderly group (p < 0.01). If an EF-HMR containing taurine for prevention of dementia was developed, willingness to buy such a food was significantly higher in the elderly group than in those 40-49 years and 50-64 years groups (p < 0.01). Regarding cooked EF-HMR containing taurine, semi-prepared and ready-made meals were preferred in 71.1% and 25.4% in 40-49 years group, 69.6% and 22.6% in 50-64 years group, and 47.0% and 33.7% in the elderly group, respectively (p < 0.001). EF-HMR containing taurine sales unit sizes containing 3 servings or 1 serving was preferred by 37.2% and 26.3% of all subjects. The preferred places to purchase EF-HMR (in descending order of super-supermarket (mart), supermarket, and convenience store) were the same among the age groups. Therefore, it is necessary to understand the diversity present in the needs and purchasing characteristics of adults involved purchasing EF-HMR containing taurine, and there is a need to develop age-specific customized products for the elderly and for Korean adults 40-64 years old.
Assuntos
Demência/prevenção & controle , Alimentos Fortificados , Taurina/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Estado Nutricional , República da CoreiaRESUMO
Although there has been substantial advancement in the development of nanostructures, the development of self-assembled nanostructures that can selectively recognize multivalent targets has been very difficult. Here we show the proof of concept that topology-controlled peptide nanoassemblies can selectively recognize and detect a multivalent RNA target. We compared the differential behaviors of peptides in a linear or cyclic topology in terms of peptide-gold nanoparticle hybrid nanostructure formation, conformational stabilization, monovalent and multivalent RNA binding in vitro, and multivalent RNA recognition in live cells. When the topology-dependent selectivity amplification of the cyclic peptide hybrids is combined with the noninvasive nature of dark-field microscopy, the cellular localization of the viral Rev response element (RRE) RNA can be monitored in situ. Because intracellular interactions are often mediated by overlapping binding partners with weak affinity, the topology-controlled peptide assemblies can provide a versatile means to convert weak ligands into multivalent ligands with high affinity and selectivity.
Assuntos
Nanoestruturas , Peptídeos Cíclicos/química , RNA/química , Microscopia Eletrônica de TransmissãoRESUMO
Here, we report on a ratiometric fluorescence biosensor based on self-assembled peptide nanostructures (SPN), which can respond to conformational changes induced by RNA ligand binding. The design of the SPN biosensor was inspired by the conformational stabilization and multimerization behaviors of the HIV-1 Rev protein induced by cooperative protein-protein and protein-RNA interactions. Because conformation-sensitive SPN biosensors can orchestrate binding and signal transduction events, they can be developed as highly sophisticated and smart nanomaterials for biosensing.
Assuntos
Corantes Fluorescentes/química , Nanopartículas/química , Peptídeos/química , RNA Fúngico/química , Produtos do Gene rev do Vírus da Imunodeficiência Humana/química , Técnicas Biossensoriais , Ligação Proteica , Multimerização Proteica , Estabilidade Proteica , Espectrometria de Fluorescência , Difração de Raios XRESUMO
Platycodin D (PD) is the main component of triterpene saponins found in Platycodi radix. In this study, we observed a decrease in cell viability, an increase in apoptotic bodies, and an increase in the rate of apoptosis. Also, we observed an increase in cleaved PARP and Bax, a decrease in Bcl-2, and p-ERK, and an increase in p-p38 and p-JNK. Furthermore, a change in cell viability and the expression of p-p38, Bax, and Bcl-2 using the p38 inhibitor revealed a decrease in p-p38 and Bax and an increase in Bcl-2 in the inhibitor treatment group. In addition, we observed an increase in vacuole formation through morphological changes and an increase in acidic vesicular organelles (AVOs). We also observed an increase in the expression of beclin 1, LC 3-I, and -II. There was no significant decrease in cell viability in the group treated with 3-MA, but a decrease in cell viability was noted in the group treated with HCQ. HCQ treatment resulted in an increase in Bax and a decrease in Bcl-2. These findings reveal that in HT-29 colon cancer cells, PD induces apoptosis through the MAPK pathway, thereby exerting anticancer effects. Moreover, autophagy caused by PD inhibits apoptosis by protecting the cells.
Assuntos
Neoplasias do Colo , Saponinas , Triterpenos , Humanos , Proteína X Associada a bcl-2 , Saponinas/farmacologia , Triterpenos/farmacologia , Apoptose , Autofagia , Neoplasias do Colo/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2RESUMO
This study sought to determine the anticancer effect of kaempferol, a glycone-type flavonoid glycoside with various pharmacological benefits, on human oral cancer MC-3 cells. In vitro studies comprised a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, annexin V and propidium iodide staining, western blotting analysis, and acridine orange staining, while the in vivo studies entailed a xenograft model, hematoxylin and eosin staining, and TdT-mediated dUTP-biotin nick end labelling. In vitro, kaempferol reduced the rate of survival of MC-3 cells, mediated intrinsic apoptosis, increased the number of acidic vesicular organelles, and altered the expression of autophagy-related proteins. Further, treatment with the autophagy inhibitors revealed that the induced autophagy had a cytoprotective effect on apoptosis in kaempferol-treated MC-3 cells. Kaempferol also decreased the expression of phosphorylated extracellular signal-regulated kinase and increased that of phosphorylated c-Jun N-terminal kinase (p-JNK) and phosphorylated p38 kinase in MC-3 cells, suggesting the occurrence of mitogen-activated protein kinase-mediated apoptosis and JNK-mediated autophagy. In vivo, kaempferol reduced tumor growth inducing apoptosis and autophagy. These results showed that kaempferol has the potential use as an adjunctive agent in treating oral cancer.
RESUMO
Gastric cancer is the fifth most common cancer globally and the third leading cause of cancer-related mortality. Existing treatment strategies for gastric cancer often present numerous side effects. Consequently, recent studies have shifted toward devising new treatments grounded in safer natural substances. α-Pinene, a natural terpene found in the essential oils of various plants, such as Lavender angustifolia and Satureja myrtifolia, displays antioxidant, antibiotic, and anticancer properties. Yet, its impact on gastric cancer remains unexplored. This research assessed the effects of α-pinene in vitro using a human gastric adenocarcinoma cell-line (AGS) human gastric cancer cells and in vivo via a xenograft mouse model. The survival rate of AGS cells treated with α-pinene was notably lower than that of the control group, as revealed by the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide assay. This decline in cell viability was linked to apoptosis, as verified by 4',6-diamidino-2-phenylindole and annexin V/propidium iodide staining. The α-pinene-treated group exhibited elevated cleaved-poly (ADP-ribose) polymerase and B cell lymphoma 2 (Bcl-2)-associated X (Bax) levels and reduced Bcl-2 levels compared with the control levels. Moreover, α-pinene triggered the activation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 within the mitogen-activated protein kinase (MAPK) pathway. In the xenograft mouse model, α-pinene induced apoptosis through the MAPK pathway, devoid of toxicity. These findings position α-pinene as a promising natural therapeutic for gastric cancer.
Assuntos
Monoterpenos Bicíclicos , Neoplasias Gástricas , Humanos , Animais , Camundongos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Linhagem Celular Tumoral , Apoptose , MAP Quinases Reguladas por Sinal Extracelular , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proliferação de CélulasRESUMO
The stabilization of peptide's active conformation is a critical determinant of its target binding efficiency. Here we present a structure-based self-assembly strategy for the design of nanostructures with multiple and thermostable α-helices using bioinspired peptide amphiphiles. The design principle was inspired by the oligomerization of the human immunodeficiency virus type-1 (HIV-1) Rev protein. Our goal was to find a strategy to modify the Rev protein into a chemically manageable self-assembling peptide while stabilizing its α-helical structure. Instead of using cyclic peptides for structure stabilization, this strategy utilizes the pseudocyclization for helix stabilization. The self-assembly induced stabilization of α-helical conformation could be observed, and the α-helices were found to be stable even at high temperature (at least up to 74 °C). Conjugation of a hydrophobic alkyl chain to the Rev peptide was crucial for forming the self-assembled nanostructures, and no nanostructures could be obtained without this modification. Because chemical modifications to the α-helical peptide domain can be avoided, potentially any α-helical peptide fragment can be grafted into this self-assembling peptide scaffold.
Assuntos
Nanofibras/química , Ácidos Esteáricos/química , Tensoativos/química , Produtos do Gene rev do Vírus da Imunodeficiência Humana/química , Sequência de Aminoácidos , Dicroísmo Circular , HIV-1/química , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Nanofibras/ultraestrutura , Multimerização Proteica , Estabilidade Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de ProteínaRESUMO
BACKGROUND/AIM: The toxic side effects of therapies against breast cancer can affect the quality of life of patients, necessitating the use of naturally-derived therapeutics. Here, we investigated the effects of Dendropanax morbiferus H. Lév. leaf (DPL) extract on breast cancer cells in vitro and in vivo to assess its anticancer potential. MATERIALS AND METHODS: MDA-MB-231 breast cancer cells were treated with DPL, and the in vitro effect of DPL on the cells was evaluated through an MTT assay, DAPI staining, annexin V/propidium iodide double staining, and western blotting. The in vivo effects of DPL were measured through the MDA-MB-231 tumor xenograft mouse model. A TUNEL assay and immunohistochemistry were used to determine the extent of apoptosis and p-p38 expression in tumor tissues, respectively. RESULTS: DPL treatment significantly suppressed cell viability in a concentration-dependent manner. Furthermore, DPL treatment resulted in increased apoptotic body formation, apoptosis rate, cleaved poly (ADP-ribose) polymerase and B-cell lymphoma 2 (Bcl-2)-associated X protein levels, phosphorylation of mitogen-activated protein kinase (MAPK) pathway proteins, and decreased Bcl-2 levels. In addition, the antitumor effect in vivo was confirmed through the xenograft model, where decreased tumor volume and weight following DPL administration were observed. Further, apoptosis and increased p-p38 levels in tumor tissues were observed, and no pathological abnormalities were found in the liver or kidney. CONCLUSION: DPL inhibits proliferation through MAPK-mediated apoptosis in breast cancer cells and tumors, suggesting the potential of DPL as a natural therapeutic agent for breast cancer.
Assuntos
Neoplasias da Mama , Proteínas Quinases Ativadas por Mitógeno , Humanos , Animais , Camundongos , Feminino , Qualidade de Vida , Proliferação de Células , Neoplasias da Mama/patologia , Apoptose , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2 , Linhagem Celular TumoralRESUMO
Understanding the dynamic behavior of nanostructural systems is important during the development of controllable and tailor-made nanomaterials. This is particularly true for nanostructures that are intended for biological applications because biomolecules are usually highly dynamic and responsive to external stimuli. In this Article, we investigated the structural and conformational dynamics of self-assembling bioactive ß-sheet peptide nanostructures using electron paramagnetic resonance (EPR) spectroscopy. The model peptide nanostructures are characterized by the cross-ß spine of ß-ribbon fibers and multiple RNA-binding bioactive peptides that constitute the shell of the nanostructures. We found first, that bioactive peptides at the shell of ß-ribbon nanostructure have a mobility similar to that of an isolated monomeric peptide. Second, the periphery of the cross-ß spine is more immobile than the distal part of surface-displayed bioactive peptides. Third, the rotational dynamics of short and long fibrils are similar; that is, the mobility is largely independent of the extent of aggregation. Fourth, peptides that constitute the shell are affected first by the external environment at the initial stage. The cross-ß spine resists its external environment to a certain extent and abruptly disintegrates when the perturbation reaches a certain degree. Our results provide an overall picture of ß-sheet peptide nanostructure dynamics, which should be useful in the development of dynamic self-assembled peptide nanostructures.
Assuntos
Nanoestruturas , Peptídeos/química , Proteínas de Ligação a RNA/química , Sequência de Aminoácidos , Dicroísmo Circular , Espectroscopia de Ressonância de Spin Eletrônica , Dados de Sequência MolecularRESUMO
Tenebrio molitor larvae, as known as edible insects, has advantages of being rich in protein, and has been recognized as a suitable alternate protein source for broiler and pig feed. Moreover, given their ability to biodegrade polystyrene, a major pollutant, Tenebrio molitor larvae has been proposed as an innovative solution to environmental problems. In the present study, we investigated the toxicity of Tenebrio molitor larvae powder (TMlp) ingested with expanded-polystyrene (W/ eps) through in vitro and in vivo experiments. The objective of this study was to determine whether TMlp W/ eps can be applied as livestock alternative protein source. For in vitro experiments, cytotoxicity test was performed to investigate the effects of TMlp-extract on the viability of estrogen-dependent MCF-7 cells. The possibility of estrogen response was investigated in two groups: Expanded-polystyrene-fed (W/ eps) TMlp group and without expanded-polystyrene-fed (W/o eps) TMlp group. For in vivo experiments, The male Sprague-Dawley rats were divided based on the dosage of TMlp administered and oral administration was performed to every day for 5 weeks. A toxicological assessments were performed, which included clinical signs, food consumption, body and organ weights, hematology, serum chemistry, and hematoxylin and eosin staining of liver and kidney. There were no specific adverse effect of TMlp W/ eps-related findings under the experimental conditions of this study, but further studies on both sexes and animal species differences should be investigated. In conclusion, TMlp W/ eps was considered non-toxic and observed to be applicable as an alternative protein source for livestock feed.
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Myricetin, a natural flavonoid present in berries, nuts, and green tea, is well-known for its anticancer properties. Even though several previous studies have reported the anticancer effects induced by myricetin, these effects have not yet been confirmed in the adenocarcinoma gastric cell line (AGS). Moreover, the exact mechanisms of myricetin-induced apoptosis and autophagy have not been clearly identified either. Therefore, in this study, we aimed to examine the role of myricetin in inducing apoptosis and autophagy in AGS gastric cancer cells. First, the survival rate of AGS gastric cancer cells was assessed using the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) cell viability assay. Thereafter, the rate of apoptosis was analyzed using4',6-diamidino-2-phenylindole (DAPI) staining as well as annexin V and propidium iodide (PI) staining, and the expression of the proteins associated with apoptosis, PI3K/Akt/mTOR pathway, and autophagy was examined by western blotting. We observed that myricetin reduced the survival rate of AGS gastric cancer cells by inhibiting the PI3K/Akt/mTOR pathway, thereby inducing apoptosis and autophagy. Similar results were also obtained in vivo, and tumor growth was inhibited. Therefore, in the AGS gastric cancer cells, myricetin seems to inhibit the PI3K/Akt/mTOR pathway, which in turn leads to apoptosis in vitroand in vivo, cell-protective autophagy, as well as inhibition of cancer cell proliferation. These results indicate the potential of myricetin as a natural anticancer agent.
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Myricetin, a flavonoid found in fruits and vegetables, is known to have antioxidant and anticancer effects. However, the anticancer effects of myricetin on SKBR3 human breast cancer cells have not been elucidated. In the present study, the anticancer effects of myricetin were confirmed in human breast cancer SKBR3 cells. As the concentration of myricetin increased, the cell viability decreased. DAPI (4',6diamidino2phenylindole) and Annexin V/PI staining also revealed a significant increase in apoptotic bodies and apoptosis. Western blot analysis was performed to confirm the myricetininduced expression of apoptosisrelated proteins. The levels of cleaved PARP and Bax proteins were increased, and that of Bcl2 was decreased. The levels of proteins in the mitogenactivated protein kinase (MAPK) pathway were examined to confirm the mechanism of myricetininduced apoptosis, and it was found that the expression levels of phosphorylated cJun Nterminal kinase (pJNK) and phosphorylated mitogenactivated protein kinases (pp38) were increased, whereas that of phosphorylated extracellularregulated kinase (pERK) was decreased. It was also demonstrated that myricetin induced autophagy by promoting autophagyrelated proteins such as microtubuleassociated protein 1A/1Blight chain 3 (LC 3) and beclin 1. In addition, 3methyladenine (3MA) was used to evaluate the association between cell viability and autophagy in cells treated with myricetin. The results showed that simultaneous treatment with 3MA and myricetin promoted the apoptosis of breast cancer cells. Furthermore, treatment with a JNK inhibitor reduced cell viability, promoted Bax expression, and reduced the expression of pJNK, Bcl2, and LC 3II/I. These results suggest that myricetin induces apoptosis via the MAPK pathway and regulates JNKmediated autophagy in SKBR3 cells. In conclusion, myricetin shows potential as a natural anticancer agent in SKBR3 cells.
Assuntos
Apoptose , Flavonoides , Sistema de Sinalização das MAP Quinases , Proteínas Quinases Ativadas por Mitógeno , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Flavonoides/farmacologia , HumanosRESUMO
Chrysin is known to exert anti-inflammatory, antioxidant, and anticancer effects. The aim of this study was to investigate the anticancer effects of chrysin in the human melanoma cells A375SM and A375P. The results obtained demonstrated successful inhibition of the viability of these cells by inducing apoptosis and autophagy. This was confirmed by the level of apoptosis-related proteins: Bax and cleaved poly (ADP-ribose) polymerase both increased, and Bcl-2 decreased. Moreover, levels of LC3 and Beclin 1, both autophagy-related proteins, increased in chrysin-treated cells. Autophagic vacuoles and acidic vesicular organelles were observed in both cell lines treated with chrysin. Both cell lines showed different tendencies during chrysin-induced autophagy inhibition, indicating that autophagy has different effects depending on the cell type. In A375SM, the early autophagy inhibitor 3-methyladenine (3-MA) was unaffected; however, cell viability decreased when treated with the late autophagy inhibitor hydroxychloroquine (HCQ). In contrast, HCQ was unaffected in A375P; however, cell viability increased when treated with 3-MA. Chrysin also decreased the phosphorylation of mTOR/S6K pathway proteins, indicating that this pathway is involved in chrysin-induced apoptosis and autophagy for A375SM and A375P. However, studies to elucidate the mechanisms of autophagy and the action of chrysin in vivo are still needed.