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1.
Eur J Pharm Sci ; 190: 106579, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37689120

RESUMO

Cancer drug resistance is an ever-changing problem that most patients need to face in their later stages of treatment, especially the multidrug resistant (MDR) type. The drug efflux transporters, including P-glycoprotein (P-gp), multidrug resistance protein 1 (MRP1), and breast cancer resistance protein (BCRP), play the crucial roles in this sophisticated battle. In recent decades, researchers try to find potential inhibitors to impede the drug efflux function of above transporters. d-α-Tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS) is a prevalently used excipient in the formulation design. In the present study, the modulatory effects and mechanisms of vitamin E TPGS on the efflux transporters were investigated. And the cancer MDR reversing ability of vitamin E TPGS was evaluated as well. Stable-cloned transporter over-expressed cell lines were used for mechanisms study, while several types of MDR cancer cell lines were adopted as reversing evaluation models. The results exhibited that vitamin E TPGS significantly inhibited the efflux function of P-gp, MRP1, and BCRP under non-cytotoxic concentrations, but not influencing the protein expression levels. Through efflux assay and molecular docking, vitamin E TPGS was found to be an uncompetitive, non-competitive, and competitive inhibitor on chemotherapeutic drug doxorubicin efflux in P-gp, MRP1, and BCRP over-expressing cell lines, respectively. Furthermore, the basal ATPase activity of three transporters were significantly inhibited by vitamin E TPGS at 10 µM. And the cell membrane fluidity of P-gp over-expressing cell line was enhanced by 22.58% with 5 µM vitamin E TPGS treatment, compared to the parental Flp-In™-293 cell line (without P-gp). The resistance reversing ability of vitamin E TPGS was prominent in MCF-7/DOX MDR breast cancer cell line, which over-expressed P-gp, MRP1, and BCRP. These significant results suggested that vitamin E TPGS is a promising modulator on transporters mediated cancer MDR. Vitamin E TPGS is not an inert excipient, but possesses MDR-reversing pharmacological effects, and deserves a re-purposing application on the future combinatorial regimen design for MDR cancer treatment.

2.
Mov Disord ; 38(12): 2217-2229, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37752895

RESUMO

BACKGROUND: Rare mutations in NADH:ubiquinone oxidoreductase complex assembly factor 5 (NDUFAF5) are linked to Leigh syndrome. OBJECTIVE: We aimed to describe clinical characteristics and functional findings in a patient cohort with NDUFAF5 mutations. METHODS: Patients with biallelic NDUFAF5 mutations were recruited from multi-centers in Taiwan. Clinical, laboratory, radiological, and follow-up features were recorded and mitochondrial assays were performed in patients' skin fibroblasts. RESULTS: Nine patients from seven unrelated pedigrees were enrolled, eight homozygous for c.836 T > G (p.Met279Arg) in NDUFAF5 and one compound heterozygous for p.Met279Arg. Onset age had a bimodal distribution. The early-onset group (age <3 years) presented with psychomotor delay, seizure, respiratory failure, and hyponatremia. The late-onset group (age ≥5 years) presented with normal development, but slowly progressive dystonia. Combing 25 previously described patients, the p.Met279Arg variant was exclusively identified in Chinese ancestry. Compared with other groups, patients with late-onset homozygous p.Met279Arg were older at onset (P = 0.008), had less developmental delay (P = 0.01), less hyponatremia (P = 0.01), and better prognosis with preserved ambulatory function into early adulthood (P = 0.01). Bilateral basal ganglia necrosis was a common radiological feature, but brainstem and spinal cord involvement was more common with early-onset patients (P = 0.02). A modifier gene analysis showed higher concomitant mutation burden in early-versus late-onset p.Met279Arg homozygous cases (P = 0.04), consistent with more impaired mitochondrial function in fibroblasts from an early-onset case than a late-onset patient. CONCLUSIONS: The p.Met279Arg variant is a common mutation in our population with phenotypic heterogeneity and divergent prognosis based on age at onset. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Distúrbios Distônicos , Hiponatremia , Doença de Leigh , Transtornos dos Movimentos , Pré-Escolar , Humanos , Distúrbios Distônicos/complicações , Hiponatremia/complicações , Doença de Leigh/genética , Doença de Leigh/complicações , Metiltransferases/genética , Proteínas Mitocondriais/genética , Transtornos dos Movimentos/complicações , Mutação/genética , Criança , Adulto Jovem
3.
J Cell Biol ; 222(10)2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37584589

RESUMO

Mitochondria are dynamic organelles regulated by fission and fusion processes. The fusion of membranes requires elaborative coordination of proteins and lipids and is particularly crucial for the function and quality control of mitochondria. Phosphatidic acid (PA) on the mitochondrial outer membrane generated by PLD6 facilitates the fusion of mitochondria. However, how PA promotes mitochondrial fusion remains unclear. Here, we show that a mitochondrial outer membrane protein, NME3, is required for PLD6-induced mitochondrial tethering or clustering. NME3 is enriched at the contact interface of two closely positioned mitochondria depending on PLD6, and NME3 binds directly to PA-exposed lipid packing defects via its N-terminal amphipathic helix. The PA binding function and hexamerization confer NME3 mitochondrial tethering activity. Importantly, nutrient starvation enhances the enrichment efficiency of NME3 at the mitochondrial contact interface, and the tethering ability of NME3 contributes to fusion efficiency. Together, our findings demonstrate NME3 as a tethering protein promoting selective fusion between PLD6-remodeled mitochondria for quality control.


Assuntos
Mitocôndrias , Nucleosídeo NM23 Difosfato Quinases , Ácidos Fosfatídicos , Fosfolipase D , Humanos , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Ácidos Fosfatídicos/metabolismo , Fosfolipase D/metabolismo
4.
Healthcare (Basel) ; 11(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37239748

RESUMO

The psychosocial and health consequences of ocular conditions that cause visual impairment (VI) are extensive and include impaired daily activities, social isolation, cognitive impairment, impaired functional status and functional decline, increased reliance on others, increased risk of motor vehicle accidents, falls and fractures, poor self-rated health, and depression. We aimed to determine whether VI increases the likelihood of a poor prognosis, including mental illness, suicide, and mortality over time. In this large, location, population-based, nested, cohort study, we used data from 2000 to 2015 in the Taiwan National Health Insurance Research Database (NHIRD), which includes diagnoses of all the patients with VI. Baseline features, comorbidities, and prognostic variables were evaluated using a 1:4-matched cohort analysis. Furthermore, comparisons were performed using Cox regression and Bonferroni-correction (for multiple comparisons) to study the association between VI and poor prognosis (mental illness, suicide). The study outcome was the cumulative incidence of poor prognosis among the visually impaired and controls. A two-tailed Bonferroni-corrected p < 0.001 was considered statistically significant. Among the 1,949,101 patients enlisted in the NHIRD, 271 had been diagnosed with VI. Risk factors for poor prognosis and the crude hazard ratio was 3.004 (95% confidence interval 2.135-4.121, p < 0.001). Participants with VI had an increased risk of poor prognosis according to the sensitivity analysis, with a poor prognosis within the first year and first five years. VI was associated with suicide and mental health risks. This study revealed that patients with VI have a nearly 3-fold higher risk of psychiatric disorders, including anxiety, depression, bipolar, and sleep disorders, than the general population. Early detection through comprehensive examinations based on increased awareness in the clinical context may help maintain visual function and avoid additional complications.

5.
PLoS One ; 17(10): e0276690, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36282879

RESUMO

The complex effects of alcohol consumption on the cardiovascular system vary with mean daily consumption and duration of intake. This population-based retrospective cohort study aimed to explore the risk of cardiovascular disease (CVD) in patients with alcohol use disorder (AUD). Data was collected from the Taiwan National Health Insurance Research Database from 2000 to 2013. A total of 7,420 patients with AUD were included in our study group, and 29,680 age- and sex-matched controls without AUD in the control group. Cox proportional hazard regression analysis was used to investigate the effects of AUD on the risk of CVD. Most patients were men aged 25-44 years. At the end of the follow-up period, the AUD group had a significantly higher incidence of CVD (27.39% vs. 19.97%, P<0.001) and more comorbidities than the control group. The AUD group also exhibited a significantly higher incidence of CVD than the control group based on the Cox regression analysis and Fine and Gray's competing risk model (adjusted hazard ratio [AHR] = 1.447, 95% confidence interval [CI] = 1.372-1.52 5, P<0.001). Furthermore, male sex, diabetes mellitus, hypertension, hyperlipidemia, chronic kidney disease, chronic obstructive pulmonary disease, anxiety, depression, and a high Charlson Comorbidity Index were also associated with an increased risk of CVD. Patients with AUD in different CVD subgroups, such as those with CVD, ischemic heart disease (IHD), and stroke, were at a significantly higher risk of disease than those without AUD; CVD (AHR = 1.447, 95% CI = 1.372-1.525, P<0.001), IHD (AHR = 1.304, 95% CI = 1.214-1.401, P<0.001), and stroke (AHR = 1.640, 95% CI = 1.519-1.770, P<0.001). The risk also significantly differed among patients in the different CVD subgroups. We observed an association between AUD and development of CVD even after adjusting for several comorbidities and medications in our nationwide population cohort.


Assuntos
Alcoolismo , Doenças Cardiovasculares , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Estudos Retrospectivos , Alcoolismo/complicações , Alcoolismo/epidemiologia , Doenças Cardiovasculares/epidemiologia , Fatores de Risco , Estudos de Coortes , Incidência , Comorbidade , Modelos de Riscos Proporcionais , Acidente Vascular Cerebral/epidemiologia , Consumo de Bebidas Alcoólicas , Taiwan/epidemiologia
6.
Front Pharmacol ; 13: 879748, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35662690

RESUMO

Breast cancer is the most prevalent cancer and the second leading cause of cancer death in women. Cisplatin is a commonly used chemotherapeutic drug for breast cancer treatment. Owing to serious side effects, the combination of cisplatin with other drugs is an effective strategy to simultaneously reduce side effects and increase the anticancer efficacy. GLUT1 is an emerging target for cancer treatment since cancer cells usually consume more glucose, a phenomenon called the Warburg effect. In this study, we found that the combination of cisplatin and a novel GLUT1 inhibitor #43 identified from our previous high-throughput screening exerted a synergistic anticancer effect in MCF-7 and MDA-MB-231 breast cancer cells. Mechanism studies in MCF-7 cells revealed that combination of cisplatin and #43 significantly induced apoptosis, intracellular reactive oxygen species, and loss of mitochondrial membrane potential. Furthermore, #43 enhanced the DNA damaging effect of cisplatin. Akt/mTOR downstream signaling and the ERK signaling pathway usually involved in cell growth and survival were inhibited by the combination treatment. On the other hand, phosphorylation of p38 and JNK, which may be associated with apoptosis, was induced by the combination treatment. Altogether, our data indicate that oxidative stress, DNA damage, the Akt/mTOR and MAPK signaling pathways, and apoptosis may be involved in the synergism of cisplatin and #43 in breast cancer cells.

7.
Biotechnol Bioeng ; 117(4): 933-944, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31889302

RESUMO

Rice straw, a common agricultural waste, is used as a potential feedstock for bioethanol production. Currently, bioethanol is made mostly from the microbial fermentation of starch-containing raw materials. Therefore, genetically engineered starch-excess rice straw through interference of starch degradation as a potential strategy to enhance bioethanol production was evaluated in this study. Arabidopsis Starch Excess 4 (SEX4) encodes a chloroplast-localized glucan phosphatase and plays a role in transitory starch degradation. Despite the identification of a SEX4 homolog in rice, OsSEX4, its biological function remains uncertain. Ectopic expression of OsSEX4 complementary DNA complemented the leaf starch-excess phenotype of the Arabidopsis sex4-4 mutant. OsSEX4-knockdown transgenic rice plants were generated using the RNA interference approach. Starch accumulation was higher in OsSEX4-knockdown suspension-cultured cells, leaves, and rice straw compared with the wild type, suggesting that OsSEX4 plays an important role in degradation of transitory starch. The OsSEX4-knockdown rice plants showed normal plant growth and no yield penalty. Starch-excess OsSEX4-knockdown rice straw used as feedstock for fermentation resulted in improved bioethanol yield, with a 50% increase in ethanol production in a vertical mass-flow type bioreactor, compared with that of the wild-type straw.


Assuntos
Fosfatases de Especificidade Dupla , Etanol/metabolismo , Oryza , Proteínas de Plantas , Amido , Biocombustíveis , Reatores Biológicos , Fosfatases de Especificidade Dupla/genética , Fosfatases de Especificidade Dupla/metabolismo , Técnicas de Silenciamento de Genes , Engenharia Genética/métodos , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Amido/genética , Amido/metabolismo
8.
Food Chem Toxicol ; 103: 157-167, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28284729

RESUMO

Di(2-ethylhexyl)phthalate (DEHP) may cause carcinogenicity in the liver; however, few have detailed on the potential effects of DEHP exposure on colorectal cancer. Male Sprague-Dawley rats received i.p. injections of 1,2-dimethylhydrazine (DMH) once-a-week for the first 4 weeks, and rats in each group were treated with DEHP through oral gavage daily for either 7, 10 or 15 weeks; after which, all rats were euthanized and their colons were assessed (a) morphologically for aberrant crypt foci (ACF) or tumors, (b) cytologically for mitotic index (MI), and (c) immunohistochemically for the expression of ß-catenin, cyclooygenase (COX)-2, vascular endothelial growth factor (VEGF), proliferating cell nuclear antigen (PCNA), cyclin D1, and c-myc. Our results indicated that the mean total ACF, tumor incidence, and MI were significantly higher in the DEHP-treated DMH compared to control and the DEHP-alone groups. The level of ß-catenin and cyclin D1 was increased in DEHP-exposed rats. Expression of ß-catenin, COX-2, VEGF, and cyclin D1 was significantly higher in the combined DMH and DEHP-treated rats by comparison to that of the DMH group. In conclusion, this study indicates that exposure to DEHP may exacerbate DMH-induced colon tumorigenesis and provides impetus to evaluate the effect of DEHP in conjunction with other carcinogens.


Assuntos
1,2-Dimetilidrazina/toxicidade , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Dietilexilftalato/toxicidade , Animais , Neoplasias do Colo/metabolismo , Ciclina D1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Fígado/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo , beta Catenina/metabolismo
9.
Int J Mol Sci ; 14(5): 8719-39, 2013 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-23615467

RESUMO

Application of plant expression systems in the production of recombinant proteins has several advantages, such as low maintenance cost, absence of human pathogens, and possession of complex post-translational glycosylation capabilities. Plants have been successfully used to produce recombinant cytokines, vaccines, antibodies, and other proteins, and rice (Oryza sativa) is a potential plant used as recombinant protein expression system. After successful transformation, transgenic rice cells can be either regenerated into whole plants or grown as cell cultures that can be upscaled into bioreactors. This review summarizes recent advances in the production of different recombinant protein produced in rice and describes their production methods as well as methods to improve protein yield and quality. Glycosylation and its impact in plant development and protein production are discussed, and several methods of improving yield and quality that have not been incorporated in rice expression systems are also proposed. Finally, different bioreactor options are explored and their advantages are analyzed.


Assuntos
Biotecnologia/métodos , Oryza/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/uso terapêutico , Expressão Gênica , Humanos , Plantas Geneticamente Modificadas
10.
Med Dosim ; 36(1): 62-70, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20188537

RESUMO

The dosimetric results of stereotactic radiosurgery (SRS) for vestibular schwannoma (VS) performed using dynamic conformal arc therapy (DCAT) with the Novalis system and helical TomoTherapy (HT) were compared using plan quality indices. The HT plans were created for 10 consecutive patients with VS previously treated with SRS using the Novalis system. The dosimetric indices used to compare the techniques included the conformity index (CI) and homogeneity index (HI) for the planned target volume (PTV), the comprehensive quality index (CQI) for nine organs at risk (OARs), gradient score index (GSI) for the dose drop-off outside the PTV, and plan quality index (PQI), which was verified using the plan quality discerning power (PQDP) to incorporate 3 plan indices, to evaluate the rival plans. The PTV ranged from 0.27-19.99 cm(3) (median 3.39 cm(3)), with minimum required PTV prescribed doses of 10-16 Gy (median 12 Gy). Both systems satisfied the minimum required PTV prescription doses. HT conformed better to the PTV (CI: 1.51 ± 0.23 vs. 1.94 ± 0.34; p < 0.01), but had a worse drop-off outside the PTV (GSI: 40.3 ± 10.9 vs. 64.9 ± 13.6; p < 0.01) compared with DCAT. No significant difference in PTV homogeneity was observed (HI: 1.08 ± 0.03 vs. 1.09 ± 0.02; p = 0.20). HT had a significantly lower maximum dose in 4 OARs and significant lower mean dose in 1 OAR; by contrast, DCAT had a significantly lower maximum dose in 1 OAR and significant lower mean dose in 2 OARs, with the CQI of the 9 OARs = 0.92 ± 0.45. Plan analysis using PQI (HT 0.37 ± 0.12 vs. DCAT 0.65 ± 0.08; p < 0.01), and verified using the PQDP, confirmed the dosimetric advantage of HT. However, the HT system had a longer beam-on time (33.2 ± 7.4 vs. 4.6 ± 0.9 min; p < 0.01) and consumed more monitor units (16772 ± 3803 vs. 1776 ± 356.3; p < 0.01). HT had a better dose conformity and similar dose homogeneity but worse dose gradient than DCAT. Plan analysis confirmed the dosimetric advantage of HT, although not all indices revealed a better outcome for HT. Whether this dosimetric advantage translates into a clinical benefit deserves further investigation.


Assuntos
Algoritmos , Neuroma Acústico/cirurgia , Proteção Radiológica/métodos , Radiometria/métodos , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Dosagem Radioterapêutica
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