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1.
Biomedicines ; 12(8)2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39200376

RESUMO

Probiotics and prebiotics have gained attention for their potential health benefits. However, their efficacy hinges on probiotic survival through the harsh gastrointestinal environment. Microencapsulation techniques provide a solution, with resistant starch (RS)-based techniques showing promise in maintaining probiotic viability. Specifically, RS-encapsulated probiotics significantly improved probiotic survival in gastric acid, bile salts, and simulated intestinal conditions. This study investigated the effects of a resistant-starch-encapsulated probiotic cocktail (RS-Pro) in the context of 5-fluorouracil (5-FU) chemotherapy, which frequently induces microbiota dysbiosis and intestinal mucositis. Female BALB/c mice were divided into three groups: a 5-FU group, a 5-FU+Pro group receiving free probiotics, and a 5-FU+RS-Pro group receiving RS-encapsulated probiotics. After 28 days of treatment, analyses were conducted on fecal microbiota, intestinal histology, peripheral blood cell counts, and body and organ weights. It was revealed by 16S rRNA MiSeq sequencing that 5-FU treatment disrupted gut microbiota composition, reduced microbial diversity, and caused dysbiosis. RS-Pro treatment restored microbial diversity and increased the population of beneficial bacteria, such as Muribaculaceae, which play roles in carbohydrate and polyphenol metabolism. Furthermore, 5-FU administration induced moderate intestinal mucositis, characterized by reduced cellularity and shortened villi. However, RS-Pro treatment attenuated 5-FU-induced intestinal damage, preserving villus length. Mild leukopenia observed in the 5-FU-treated mice was partially alleviated in 5-FU+Pro and 5-FU+RS-Pro groups. These findings suggest that RS-Pro may serve as an adjunct to chemotherapy, potentially reducing adverse effects and improving therapeutic outcomes in future clinical applications.

2.
Biomedicines ; 12(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39062024

RESUMO

5-Fluorouracil (5-FU) is commonly used as the primary chemotherapy for colorectal cancer (CRC). However, it can lead to unwanted chemoresistance. Resistant starch (RS), which functions similarly to fermentable dietary fiber, has the potential to reduce the risk of CRC. The effects of RS on improving CRC-associated cachectic symptoms and 5-FU chemotherapy-induced microbial dysbiosis remain unknown. Female BALB/cByJNarl mice were randomly divided into four groups: one tumor group (with CT26 colonic carcinoma but no treatment) and three CT26 colonic carcinoma-bearing groups that were administered 20 mg/kg 5-FU (T+5-FU group), a probiotic cocktail (4 × 108 CFUs) plus chemotherapy (T+5-FU+Pro), or resistant-starch-encapsulated probiotics plus chemotherapy (T+5-FU+RS-Pro). T+5-FU and T+5-FU+RS-Pro administration significantly suppressed tumor growth and activated apoptotic cell death in CT26-bearing mice. 5-FU-induced increases in inflammatory cytokines and NF-κB signaling were mitigated by the Pro or RS-Pro supplementation. A gut microbial composition comparison indicated that the abundance of intestinal bacteria in the T and T+5-FU groups decreased significantly, while the groups receiving Pro or RS-Pro maintained a greater abundance and healthy gut microbiota composition, suggesting that RS can reduce the microbial dysbiosis that occurs during 5-FU chemotherapy. The use of RS-Pro before chemotherapy should be considered for the regulation of chemotherapy-associated cachectic symptoms, inflammation, and chemotherapy-induced microbial dysbiosis.

3.
Health Phys ; 120(3): 353-359, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33475265

RESUMO

ABSTRACT: Radiological emergency response may require responders to operate in contaminated environments. To provide more realistic training to these individuals, it has been proposed to disperse low amounts of short-lived radioactive material in simulated emergency scenarios. To demonstrate the applicability and safety of such activities, a limited exercise was conducted where 18F was sprayed in a small area and survey activities were executed. A pre-job external radiation exposure dose assessment was performed in preparation for this training. The research presented here compares participant external recorded doses to assessment results in order to validate the dose estimates. Two individuals were used during the dispersion, search, and survey activities. First, a radiation worker mixed 200 MBq Fludeoxyglucose 18F with 470 mL H2O in a weed sprayer and distributed it over a 3 m × 3 m area. After evaporation, an exercise participant performed search and survey activities in the area. Actual whole-body doses measured with optically stimulated luminescence dosimeters were 10 ± 1 µSv for both personnel. Whole-body digital dosimeters read 4.3 ± 0.2 µSv and 3.3 ± 0.5 µSv for the radiation worker and exercise participant, respectively. Actual extremity doses were below the dosimeters' minimum detectable limits for the radiation worker (thermoluminescence dosimeter) and exercise participant (optically stimulated luminescence dosimeter). The dose assessment-predicted whole-body doses were 2.8 ± 0.4 µSv and 3.2 ± 0.1 µSv for the radiation worker and exercise participant, respectively. The estimated dose to the radiation worker's hand was 21.8 ± 3.8 µSv, and the estimated dose to the exercise participant's knee was 13.4 ± 0.6 µSv. The study provided substantial evidence for the validity of the dose assessment method, supporting its use for a larger training exercise.


Assuntos
Fluordesoxiglucose F18 , Exposição Ocupacional , Doses de Radiação , Fluordesoxiglucose F18/análise , Mãos , Humanos , Exposição Ocupacional/análise , Reprodutibilidade dos Testes
4.
Sci Rep ; 5: 15067, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26469245

RESUMO

Alzheimer's disease (AD) is the most common form of dementia. The deposition of brain amyloid-ß peptides (Aß), which are cleaved from amyloid precursor protein (APP), is one of the pathological hallmarks of AD. Aß-induced oxidative stress and neuroinflammation play important roles in the pathogenesis of AD. Antroquinonol, a ubiquinone derivative isolated from Antrodia camphorata, has been shown to reduce oxidative stress and inflammatory cytokines via activating the nuclear transcription factor erythroid-2-related factor 2 (Nrf2) pathway, which is downregulated in AD. Therefore, we examined whether antroquinonol could improve AD-like pathological and behavioral deficits in the APP transgenic mouse model. We found that antroquinonol was able to cross the blood-brain barrier and had no adverse effects via oral intake. Two months of antroquinonol consumption improved learning and memory in the Morris water maze test, reduced hippocampal Aß levels, and reduced the degree of astrogliosis. These effects may be mediated through the increase of Nrf2 and the decrease of histone deacetylase 2 (HDAC2) levels. These findings suggest that antroquinonol could have beneficial effects on AD-like deficits in APP transgenic mouse.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Aprendizagem Espacial/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Ubiquinona/análogos & derivados , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Comportamento Animal , Barreira Hematoencefálica/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Hipocampo/patologia , Histona Desacetilase 2/metabolismo , Camundongos , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2/metabolismo , Ratos , Ubiquinona/administração & dosagem , Ubiquinona/efeitos adversos , Ubiquinona/farmacocinética , Ubiquinona/farmacologia
5.
Biomed Pharmacother ; 68(8): 1007-14, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25312820

RESUMO

Antroquinonol is the smallest anticancer molecule isolated from Antrodia camphorata thus far. The ubiquinone-like structure of Antroquinonol exhibits a broad spectrum of activity against malignancies in vivo and in vitro. However, the mechanism of action of Antroquinonol remains unclear. Here, we provide evidence that Antroquinonol plays a role in the inhibition of Ras and Ras-related small GTP-binding protein functions through the inhibition of protein isoprenyl transferase activity in cancer cells. Using cell line-based assays, we found that the inactive forms of Ras and Rho proteins were significantly elevated after treatment with Antroquinonol. We also demonstrated that Antroquinonol binds directly to farnesyltransferase and geranylgeranyltransferase-I, which are key enzymes involved in activation of Ras-related proteins, and inhibits enzymes activities in vitro. Furthermore, a molecular docking analysis illustrated that the isoprenoid moiety of Antroquinonol binds along the hydrophobic cavity of farnesyltransferase similar to its natural substrate, farnesyl pyrophosphate. In contrast, the ring structure of Antroquinonol lies adjacent to the Ras-CAAX motif-binding site on farnesyltransferase. The molecular docking study also showed a reasonable correlation with the IC50 values of Antroquinonol analogues. We also found that the levels of LC3B-II and the autophagosome-associated LC3 form were also significantly increased in H838 after Antroquinonol administration. In conclusion, Antroquinonol inhibited Ras and Ras-related GTP-binding protein activation through inhibition of protein isoprenyl transferase activity, leading to activation of autophagy and associated mode of cell death in cancer cells.


Assuntos
Dimetilaliltranstransferase/antagonistas & inibidores , Genes ras/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ubiquinona/análogos & derivados , Quinases Associadas a rho/antagonistas & inibidores , Dimetilaliltranstransferase/química , Dimetilaliltranstransferase/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Genes ras/fisiologia , Células Hep G2 , Humanos , Células K562 , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Transdução de Sinais/fisiologia , Ubiquinona/farmacologia , Quinases Associadas a rho/metabolismo
6.
Pharm Res ; 29(7): 1854-65, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22359146

RESUMO

PURPOSE: To be fully exploitable in both formulation and manufacturing, a drug cocrystal needs to demonstrate simultaneous improvement of multiple key pharmaceutical properties over the pure drug crystal. The present work was aimed at investigating such feasibility with two model profen-nicotinamide cocrystals. METHODS: Phase pure 1:1 ibuprofen-nicotinamide and flurbiprofen-nicotinamide cocrystals were prepared from solutions through rapid solvent removal using rotary evaporation,and characterized by DSC, PXRD, FTIR, phase solubility measurements, equilibrium moisture sorption analysis, dissolution testing and tabletability analysis. RESULTS: Temperature-composition phase diagrams constructed from DSC data for each profen and nicotinamide crystal revealed the characteristic melting point of the 1:1 cocrystal as well as the eutectic temperatures and compositions. Both cocrystals exhibited higher intrinsic dissolution rates than the corresponding profens. The cocrystals also sorbed less moisture and displayed considerably better tabletability than the individual profens and nicotinamide. CONCLUSIONS: Phase behaviors of 1:1 profen-nicotinamide cocrystal systems were delineated by constructing their temperature-composition phase diagrams. Cocrystallization with nicotinamide can simultaneously improve tableting behavior, hygroscopicity, and dissolution performance of ibuprofen and flurbiprofen. This could pave the way for further development of such cocrystal systems into consistent, stable, efficacious and readily manufacturable drug products.


Assuntos
Analgésicos/química , Flurbiprofeno/química , Ibuprofeno/química , Niacinamida/química , Complexo Vitamínico B/química , Varredura Diferencial de Calorimetria , Cristalização/métodos , Modelos Moleculares , Difração de Pó , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos , Molhabilidade , Difração de Raios X
7.
Electrophoresis ; 32(12): 1422-32, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21692080

RESUMO

Extra-thiol groups on the α-subunit allow haptoglobin (Hp) to form a variety of native multimers which influence the biophysical and biological properties of Hp. In this work, we demonstrated how differences of multimeric conformation alter the glycosylation of Hp. The isoform distributions of different multimers were examined by an alternative approach, i.e. 3-D-(Native/IEF/SDS)-PAGE, which revealed differences in N-glycosylation among individual multimers of the same Hp sample. Glycomic mapping of permethylated N-glycan indicated that the assembled monomer and multimeric conformation modulate the degree of glycosylation, especially the reduction in terminal sialic acid residues on the bi-antennary glycan. Loss of the terminal sialic acid in the higher order multimers increases the number of terminal galactose residues, which may contribute to conformation of Hp. A molecular model of the glycosylated Hp multimer was constructed, suggesting that the effect of steric hindrance on multimeric formation is critical for the enlargement of the glycan moieties on either side of the monomer. In addition, N241 of Hp was partially glycosylated, even though this site is unaffected by steric consideration. Thus, the present study provides evidence for the alteration of glycan structures on different multimeric conformations of Hp, improving our knowledge of conformation-dependent function of this glycoprotein.


Assuntos
Haptoglobinas/química , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Feminino , Glicosilação , Haptoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Conformação Proteica , Isoformas de Proteínas , Subunidades Proteicas , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
8.
BMC Immunol ; 12: 16, 2011 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21324206

RESUMO

BACKGROUND: Severe Acute Respiratory Syndrome (SARS) is a severe respiratory illness caused by a novel virus, the SARS coronavirus (SARS-CoV). 3C-like protease (3CLpro) of SARS-CoV plays a role in processing viral polypeptide precursors and is responsible of viral maturation. However, the function of 3CLpro in host cells remains unknown. This study investigated how the 3CLpro affected the secretion of cytokines in the gene-transfected cells. RESULTS: From immunofluorescence microscopy, the localization of c-myc tagged 3CLpro was detected both in the cytoplasm and nucleus of transfected A549 cells. Expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) was significantly decreased in 3CLpro-transfected cells by both RT-PCR and ELISA, but without changes in other cytokines, i.e., IL-1ß, IL-6, IL-8, IL12p40, TNF-α, and TGF-ß. Furthermore, the protein levels of NF-kB decreased in 3CLpro-transfected A549 cells when compared to EGFP transfected cells. CONCLUSIONS: Our results suggest that the 3CLpro may suppress expression of GM-CSF in transfected A549 cells through down-regulation of NF-kB production.


Assuntos
Cisteína Endopeptidases/metabolismo , Regulação para Baixo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Proteínas Virais/metabolismo , Western Blotting , Linhagem Celular Tumoral , Proteases 3C de Coronavírus , Cisteína Endopeptidases/genética , Ensaio de Imunoadsorção Enzimática , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Subunidade p40 da Interleucina-12/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Microscopia de Fluorescência , Mutação , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Virais/genética
9.
Biotechnol Prog ; 21(4): 1297-301, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16080714

RESUMO

To elevate its bioavailability via oral administration, cyclosporine A (CsA), a hydrophobic drug, was either incorporated into olive oil directly or encapsulated in artificial oil bodies (AOBs) constituted with olive oil and phospholipid in the presence or absence of recombinant caleosin purified from Escherichia coli. The bioavailabilities of CsA in these formulations were assessed in Wistar rats in comparison with the commercial formulation, Sandimmun Neoral. Among these tests, CsA-loaded AOBs stabilized by the recombinant caleosin exhibited better bioavailability than the commercial formulation and possessed the highest maximum whole blood concentration (C(max)), 1247.4 +/- 106.8 ng/mL, in the experimental animals 4.3 +/- 0.7 h (t(max)) after oral administration. C(max) and the area under the plasma concentration-time curve (AUC(0-24)) were individually increased by 50.8% and 71.3% in the rats fed with caleosin-stabilized AOBs when compared with those fed with the reference Sandimmun Neoral. The results suggest that constitution of AOBs stabilized by caleosin may be a suitable technique to encapsulate hydrophobic drugs for oral administration.


Assuntos
Proteínas de Ligação ao Cálcio/química , Ciclosporina/farmacocinética , Óleos de Plantas/química , Proteínas de Plantas/química , Animais , Disponibilidade Biológica , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/farmacocinética , Ciclosporina/sangue , Ciclosporina/química , Composição de Medicamentos , Estabilidade de Medicamentos , Masculino , Azeite de Oliva , Proteínas de Plantas/genética , Proteínas de Plantas/farmacocinética , Ratos , Ratos Wistar , Proteínas Recombinantes/química
10.
J Agric Food Chem ; 52(12): 3982-7, 2004 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-15186126

RESUMO

Seed oil bodies are lipid storage organelles of 0.5-2 microm in diameter and comprise a triacylglycerol matrix shielded by a monolayer of phospholipids and proteins. These proteins include abundant structural proteins, oleosins, and at least two minor proteins termed caleosin and steroleosin. This study examined if artificial oil bodies (AOBs) composed of triacylglycerol and phospholipid could be stabilized by oleosin, caleosin, or steroleosin. Our results showed that stabilization effects could be realized by oleosin or caleosin but not by steroleosin. The sizes of the AOBs constituted with oleosin (0.5-2 microm) or caleosin (50-200 nm) were similar to or 10 times smaller than those of the native oil bodies. Recombinant caleosin expressed in Escherichia coli also encapsulated AOBs with a size, topology, and stability comparable to those encapsulated with native caleosin. A proteinase K digestion indicated that caleosin anchored the AOBs via its central hydrophobic domain of approximately 4 kDa. Isoelectrofocusing revealed that the isoelectric point of the caleosin-stabilized AOBs was pH 4.0. Aggregation of AOBs was observed at a pH lower than 4.5; thus, their stability and integrity were presumably contributed by surface caleosin via electronegative repulsion and steric hindrance. The caleosin-stabilized AOBs were thermostable up to 70 degrees C and potentially useful for biotechnological applications.


Assuntos
Proteínas de Ligação ao Cálcio/análise , Organelas/química , Fosfolipídeos/análise , Sementes/ultraestrutura , Triglicerídeos/análise , Proteínas de Ligação ao Cálcio/genética , Estabilidade de Medicamentos , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Proteínas de Plantas , Proteínas Recombinantes
11.
Biosci Biotechnol Biochem ; 66(10): 2146-53, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12450125

RESUMO

Oleosins are structural proteins sheltering the oil bodies of plant seeds. Two isoform classes termed H- and L-oleosin are present in diverse angiosperms. Two H-oleosins and one L-oleosin were identified in sesame oil bodies from the protein sequences deduced from their corresponding cDNA clones. Sequence analysis showed that the main difference between the H- and L-isoforms is an insertion of 18 residues in the C-terminal domain of H-oleosins. H-oleosin, presumably derived from L-oleosin, was duplicated independently in several species. All known oleosins can be classified as one of these two isoforms. Single copy or a low copy number was detected by Southern hybridization for each of the three oleosin genes in the sesame genome. Northern hybridization showed that the three oleosin genes were transcribed in maturing seeds where oil bodies are being assembled. Artificial oil bodies were reconstituted with triacylglycerol, phospholipid, and sesame oleosin isoforms. The results indicated that reconstituted oil bodies could be stabilized by both isoforms, but L-oleosin gave slightly more structural stability than H-oleosin.


Assuntos
Proteínas de Plantas/genética , Óleo de Gergelim/genética , Sesamum/genética , Northern Blotting , Southern Blotting , Western Blotting , Clonagem Molecular , DNA Complementar/biossíntese , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Biblioteca Gênica , Isomerismo , Dados de Sequência Molecular , Nefelometria e Turbidimetria , Fosfolipídeos/química , Poli A/biossíntese , RNA/isolamento & purificação , Sementes/genética , Triglicerídeos/química
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