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Inflammatory bowel disease (IBD) is a chronic, recurrent inflammatory disease caused by the destruction of the intestinal mucosal epithelium that affects a growing number of people worldwide. Although the etiology of IBD is complex and still elucidated, the role of dysbiosis and dysregulated proteolysis is well recognized. Various studies observed altered composition and diversity of gut microbiota, as well as increased proteolytic activity (PA) in serum, plasma, colonic mucosa, and fecal supernatant of IBD compared to healthy individuals. The imbalance of intestinal microecology and intestinal protein hydrolysis were gradually considered to be closely related to IBD. Notably, the pivotal role of intestinal microbiota in maintaining proteolytic balance received increasing attention. In summary, we have speculated a mesmerizing story, regarding the hidden role of PA and microbiota-derived PA hidden in IBD. Most importantly, we provided the diagnosis and therapeutic targets for IBD as well as the formulation of new treatment strategies for other digestive diseases and protease-related diseases.
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Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Humanos , Proteólise , Doenças Inflamatórias Intestinais/terapia , Intestinos , Mucosa Intestinal , DisbioseRESUMO
Ammonium nitrate (AN) is a very promising high-energy oxidant for use in solid propellants but suffers from serious hygroscopicity. While various coating materials (e.g., surfactants) have been employed to mitigate the hygroscopicity of AN, the interaction mechanisms between AN and these coatings remain inadequately understood. Here, we report the preparation of a mineral oil/stearic acid (MO/SA) hybrid coating that significantly reduces the hygroscopicity of AN. The hygroscopicity of AN is efficiently inhibited through interactions between the NH4+ of AN molecules and the -COOH of SA molecules, resulting in the formation of a dense and hydrophobic coating. Additionally, the defects in the SA coating are compensated for by the MO film. Consequently, MO/SA@AN particles with a low mass ratio of the coating (1.35 wt %) exhibit a low hygroscopicity of 7.24% after being kept in a 90% relative humidity environment at 20 °C for 24 h, representing a 48.10% decline of the hygroscopicity. Furthermore, MO/SA@AN maintains a high rate of hygroscopicity decline, at 29.5%, even at 35 °C and 90% RH after 24 h. Additionally, the hybrid coating effectively accelerates the thermal decomposition reactions of AN. This study provides valuable insights into the development of hybrid coatings with excellent antihygroscopic properties for AN.
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OBJECTIVE: The aim of our study was to explore the value of DNA (CDO1m/CELF4m) methylation detection in exfoliated cervical cells collected for screening endometrial cancer in premenopausal women with abnormal uterine bleeding. METHODS: A total of 296 premenopausal women with abnormal uterine bleeding admitted to the Department of Obstetrics and Gynecology at the Third Xiangya Hospital of Central South University from November 2021 to October 2022 were selected. Clinical characteristics, endometrial thickness measured by transvaginal ultrasound and serum CA125 were collected. Exfoliated cervical cells from the thinPrep cytogic test were collected for DNA (CDO1m/CELF4m) methylation testing. Endometrial tissue was collected under hysteroscopy for pathological diagnosis as the gold standard. A univariate logistic regression model was used to analyze risk factors for endometrial cancer. The receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to measure the diagnostic efficacy of DNA methylation detection in endometrial cancer screening of women with abnormal uterine bleeding. RESULTS: Univariate logistic regression analysis showed that age, body mass index (BMI) ≥25 kg/m2, endometrial thickness ≥11 mm, CDO1 methylation (CDO1mΔCt≤8.4), CELF4 methylation (CELF4mΔCt≤8.8), and dual gene methylation (CDO1mΔCt≤8.4 or CELF4mΔCt≤8.8) were independent risk factors for endometrial cancer in women with abnormal uterine bleeding. The odds ratio (OR) values (95% confidence interval (CI) were 0.87 (0.80-0.95), 4.76 (1.89-11.96), 8.41 (3.13-22.59), 64.49 (20.46-203.33), 12.79 (4.91-33.30), and 42.53 (11.90-152.04), respectively. Among these indicators, dual gene methylation had the higher sensitivity and specificity for endometrial cancer screening (85.7% and 87.6%). Moreover, dual gene methylation combined with BMI or endometrial thickness could further improve the screening efficiency of endometrial cancer in women with abnormal uterine bleeding. CONCLUSIONS: In premenopausal women with abnormal uterine bleeding, the clinical efficacy of DNA (CDO1m/CELF4m) methylation detection in exfoliated cervical cells for endometrial cancer screening was better than that of other noninvasive clinical indicators. In addition, dual gene methylation combined with BMI or endometrial thickness was a good predictor of endometrial cancer screening.
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Biomarcadores Tumorais , Metilação de DNA , Detecção Precoce de Câncer , Neoplasias do Endométrio , Pré-Menopausa , Hemorragia Uterina , Humanos , Feminino , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/complicações , Adulto , Hemorragia Uterina/genética , Hemorragia Uterina/diagnóstico , Hemorragia Uterina/etiologia , Pessoa de Meia-Idade , Detecção Precoce de Câncer/métodos , Biomarcadores Tumorais/genéticaRESUMO
Four undescribed prenylated flavonoids, sophoratones A-D (1-4), and 17 known flavonoids, were obtained from the aerial parts of Sophora tonkinensis. Their structures with absolute configurations were elucidated by detailed interpretation of NMR spectroscopy, mass spectrometry, and ECD calculations. Meanwhile, the ability of these compounds to inhibit the release of nitric oxide (NO) by a lipopolysaccharide induced mouse in RAW 264.7 cells was assayed. The results indicated that some compounds exhibited clear inhibitory effects, with IC50 ranging from 19.91±1.08 to 35.72±2.92â µM. These results suggest that prenylated flavonoids from the aerial parts of S. tonkinensis could potentially be used as a latent source of anti-inflammatory agents.
Assuntos
Flavonoides , Lipopolissacarídeos , Óxido Nítrico , Componentes Aéreos da Planta , Sophora , Sophora/química , Animais , Camundongos , Flavonoides/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/química , Células RAW 264.7 , Componentes Aéreos da Planta/química , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Óxido Nítrico/biossíntese , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Relação Estrutura-Atividade , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Estrutura Molecular , Relação Dose-Resposta a Droga , Sobrevivência Celular/efeitos dos fármacosRESUMO
Poly(ethylene oxide) (PEO)-based composite solid electrolytes (CSEs) are promising to accelerate commercialization of solid-state lithium metal batteries (SSLMBs). Nonetheless, this is hindered by the CSEs' limited ion conductivity at room temperature. Here, we propose design, synthesis, and application of the bioinspired neuron-like nanofillers for PEO-based CSEs. The neuron-like superhydrophobic nanofillers are synthesized by controllably grafting silicone nanofilaments onto montmorillonite nanosheets. Compared to various reported fillers, the nanofillers can greatly improve ionic conductivity (4.9×10-4â S cm-1, 30 °C), Li+ transference number (0.63), oxidation stability (5.3â V) and mechanical properties of the PEO-based CSEs because of the following facts. The distinctive neuron-like structure and the resulting synaptic-like connections establish numerous long-distance continuous channels over various directions in the PEO-based CSEs for fast and uniform Li+ transport. Consequently, the assembled SSLMBs with the CSEs and LiFePO4 or NCM811 cathodes display superior cycling stability over a wide temperature range of 50 °C to 0 °C. Surprisingly, the pouch batteries with the large-scale prepared CSEs kept working after being repeatedly bent, folded, cut or even punched in air. We believe that design of neuron-like nanofillers is a viable approach to produce CSEs with high room temperature ionic conductivity for SSLMBs.
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Identification of a drug mechanism is vital for drug development. However, it often resorts to the expensive and cumbersome omics methods along with complex data analysis. Herein, we developed a methodology to analyze organelle staining images of single cells using a deep learning algorithm (TL-ResNet50) for rapid and accurate identification of different drug mechanisms. Based on the organelle-related cell morphological changes caused by drug action, the constructed deep learning model can fast predict the drug mechanism with a high accuracy of 92%. Further analysis reveals that drug combination at different ratios can enhance a certain mechanism or generate a new mechanism. This work would highly facilitate clinical medication and drug screening.
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Aprendizado Profundo , Fluorescência , Algoritmos , FenótipoRESUMO
Lithium (Li) metal batteries are among the most promising devices for high energy storage applications but suffer from severe and irregular Li dendrite growth. Here, it is demonstrated that the issue can be well tackled by precisely designing the leaf-like membrane with hierarchical structure and exquisite fluidic channels. As a proof of concept, plant leaf-inspired membrane (PLIM) separators are prepared using natural attapulgite nanorods. The PLIM separators feature super-electrolyte-philicity, high thermal stability and high ion-selectivity. Thus, the separators can guide uniform and directed Li growth on the Li anode. The Li//PLIM//Li cell with limited Li anode shows high Coulombic efficiency and cycling stability over 1500 h with small overpotential and interface impedance. The Li//PLIM//S battery exhibits high initial capacity (1352 mAh g-1 ), cycling stability (0.019% capacity decay per cycle at 1 C over 500 cycles), rate performance (673 mAh g-1 at 4 C), and high operating temperature (65 °C). The separators can also effectively improve reversibility and cycling stability of the Li/Li cell and Li//LFP battery with carbonate-based electrolyte. As such, this work provides fresh insights into the design of bioinspired separators for dendrite-free metal batteries.
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OBJECTIVE: To analyze the feasibility and results of up-and-over access (UOA) for catheter-directed thrombolysis (CDT) in acute iliofemoral popliteal venous thrombosis (IFPVT). METHODS: From June 2020 to June 2021, a total of 26 patients (26 lower limbs) undergoing CDT for IFPVT were included. According to the vascular access, the patients were divided into UOA group (n = 11, 10 left limbs and 1 right limb) and ipsilateral popliteal vein (ILPV) (n = 15, 15 left limbs) access group. The differences in preoperative characteristics and technical details between the two groups were compared. RESULTS: Patients in UOA group were older than those in ILPV access group (67.64 ± 4.11 years VS. 52.73 ± 15.63 years, p = .003). The BMI of UOA group was significantly higher than that of ILPV access group (26.03 ± 1.62 kg/m2 VS 24.71 ± 1.46 kg/m2, p = .039). There were significantly more patients with simultaneous three comorbidities in UOA group than in ILPV access group (45.5% vs. 0, p = .043). Compared with ILPV access group, the duration of operation and fluoroscopy of UOA group were significantly longer (20.64 ± 3.41 min vs. 10.20 ± 1.42 min, p < .001; 18.18 ± 2.99 min vs. 6.13 ± 0.92 min, p < .001), but the technical success rate was significantly lower (54.5% vs. 100%, p = .007). In UOA group, the operation-related complications occurred, including catheter straying into lateral sacral vein (9.1%), retroperitoneal hematoma (9.1%), and thrombus shedding into filter (9.1%). CONCLUSION: The UOA may be attempted in patients who are unable to be prone, but this access is not an optimal pathway for CDT.
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Cateterismo Periférico , Trombose Venosa , Humanos , Terapia Trombolítica/métodos , Veia Femoral , Resultado do Tratamento , Trombose Venosa/tratamento farmacológico , Catéteres , Veia Ilíaca , Fibrinolíticos/uso terapêutico , Estudos RetrospectivosRESUMO
Glutathione S-transferases (GSTs) play a crucial role in responding to abiotic stress and are an important target for research on plant stress tolerance mechanisms. Populus euphratica is a promising candidate species for investigating the abiotic tolerance mechanisms in woody plants. In our previous study, PeGSTU58 was identified as being associated with seed salinity tolerance. In the present study, PeGSTU58 was cloned from P. euphratica and functionally characterized. PeGSTU58 encodes a Tau class GST and is located in both the cytoplasm and nucleus. Transgenic Arabidopsis overexpressing PeGSTU58 displayed enhanced tolerance to salt and drought stress. Under salt and drought stress, the transgenic plants exhibited significantly higher activities of antioxidant enzymes, including SOD, POD, CAT, and GST, compared to the wild-type (WT) plants. Additionally, the expression levels of several stress-responsive genes, including DREB2A, COR47, RD22, CYP8D11, and SOD1 were upregulated in PeGSTU58 overexpression lines compared to those in WT Arabidopsis under salt and drought stress conditions. Furthermore, yeast one-hybrid assays and luciferase analysis showed that PebHLH35 can directly bind to the promoter region of PeGSTU58 and activate its expression. These results indicated that PeGSTU58 was involved in salt and drought stress tolerances by maintaining ROS homeostasis, and its expression was positively regulated by PebHLH35.
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Arabidopsis , Populus , Arabidopsis/metabolismo , Secas , Fatores de Transcrição/metabolismo , Populus/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Cloreto de Sódio/metabolismo , Estresse Fisiológico/genética , Cloreto de Sódio na Dieta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
The phytochemical investigation of the roots of the traditional Chinese medicinal plant Sophora flavescens led to the isolation of two novel prenylflavonoids with an unusual cyclohexyl substituent instead of the common aromatic ring B, named 4',4'-dimethoxy-sophvein (17) and sophvein-4'-one (18), and 34 known compounds (1-16, 19-36). The structures of these chemical compounds were determined by spectroscopic techniques, including 1D-, 2D-NMR, and HRESIMS data. Furthermore, evaluations of nitric oxide (NO) production inhibitory activity against lipopolysaccharide (LPS)-treated RAW264.7 cells indicated that some compounds exhibited obvious inhibition effects, with IC50 ranged from 4.6 ± 1.1 to 14.4 ± 0.4 µM. Moreover, additional research demonstrated that some compounds inhibited the growth of HepG2 cells, with an IC50 ranging from 0.46 ± 0.1 to 48.6 ± 0.8 µM. These results suggest that flavonoid derivatives from the roots of S. flavescens can be used as a latent source of antiproliferative or anti-inflammatory agents.
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Flavonoides , Sophora , Flavonoides/química , Sophora flavescens , Sophora/química , Anti-Inflamatórios/farmacologia , Raízes de Plantas/química , Extratos Vegetais/farmacologia , Espectroscopia de Ressonância MagnéticaRESUMO
Right ventricular (RV) function is a critical determinant of survival in patients with pulmonary arterial hypertension (PAH). While miR-21 is known to associate with vascular remodeling in small animal models of PAH, its role in RV remodeling in large animal models has not been characterized. Herein, we investigated the role of miR-21 in RV dysfunction using a sheep model of PAH secondary to pulmonary arterial constriction (PAC). RV structural and functional remodeling were examined using ultrasound imaging. Our results showed that post PAC, RV strain significantly decreased at the basal region compared with t the control. Moreover, such dysfunction was accompanied by increases in miR-21 levels. To determine the role of miR-21 in RV remodeling secondary to PAC, we investigated the molecular alteration secondary to phenylephrine induced hypertrophy and miR21 overexpression in vitro using neonatal rat ventricular myocytes (NRVMs). We found that overexpression of miR-21 in the setting of hypertrophic stimulation augmented only the expression of proteins critical for mitosis but not cytokinesis. Strikingly, this molecular alteration was associated with an eccentric cellular hypertrophic phenotype similar to what we observed in vivo PAC animal model in sheep. Importantly, this hypertrophic change was diminished upon suppressing miR-21 in NRVMs. Collectively, our in vitro and in vivo data demonstrate that miR-21 is a critical contributor in the development of RV dysfunction and could represent a novel therapeutic target for PAH associated RV dysfunction.
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Hipertrofia Ventricular Direita/diagnóstico , Hipertrofia Ventricular Direita/etiologia , MicroRNAs/genética , Hipertensão Arterial Pulmonar/complicações , Hipertensão Arterial Pulmonar/etiologia , Remodelação Ventricular , Animais , Biomarcadores , Modelos Animais de Doenças , Suscetibilidade a Doenças , Regulação da Expressão Gênica , Ovinos , Disfunção Ventricular DireitaRESUMO
Idiopathic rapid eye movement sleep behaviour disorder (RBD) is now recognized as an early manifestation of α-synucleinopathies. Increasing experimental studies demonstrate that manipulative lesion or inactivation of the neurons within the sublaterodorsal tegmental nucleus (also known as the subcoeruleus nucleus in humans) can induce RBD-like behaviours in animals. As current RBD animal models are not established on the basis of α-synucleinopathy, they do not represent the pathological substrate of idiopathic RBD and thus cannot model the phenoconversion to Parkinson's disease. The purpose of this study was therefore to establish an α-synucleinopathy-based RBD animal model with the potential to convert to parkinsonian disorder. To this end, we first determined the functional neuroanatomical location of the sublaterodorsal tegmental nucleus in wild-type C57BL/6J mice and then validated its function by recapitulating RBD-like behaviours based on this determined nucleus. Next, we injected preformed α-synuclein fibrils into the sublaterodorsal tegmental nucleus and performed regular polysomnographic recordings and parkinsonian behavioural and histopathological studies in these mice. As a result, we recapitulated RBD-like behaviours in the mice and further showed that the α-synucleinopathy and neuron degeneration identified within the sublaterodorsal tegmental nucleus acted as the neuropathological substrates. Subsequent parkinsonian behavioural studies indicated that the α-synucleinopathy-based RBD mouse model were not stationary, but could further progress to display parkinsonian locomotor dysfunction, depression-like disorder, olfactory dysfunction and gastrointestinal dysmotility. Corresponding to that, we determined α-synuclein pathology in the substantia nigra pars compacta, olfactory bulb, enteral neuroplexus and dorsal motor nucleus of vagus nerve, which could underlie the parkinsonian manifestations in mice. In conclusion, we established a novel α-synucleinopathy-based RBD mouse model and further demonstrated the phenoconversion of RBD to Parkinson's disease in this animal model.
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Transtornos Parkinsonianos/psicologia , Transtorno do Comportamento do Sono REM/psicologia , Sinucleinopatias/psicologia , alfa-Sinucleína , Animais , Comportamento Animal , Depressão/etiologia , Depressão/psicologia , Modelos Animais de Doenças , Discinesias/etiologia , Eletroencefalografia , Eletromiografia , Motilidade Gastrointestinal , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , PolissonografiaRESUMO
Gastrodin has shown the potential as an anticonvulsant. Epilepsy is a neurological disease with significant effects in children. In the current study, the therapeutic potential of gastrodin in handling pediatric epilepsy was explored by focusing on the AMPK/PPARα pathway. Three-week-old Sprague-Dawley rats were subjected to lithium-pilocarpine method to induce epileptic symptoms and then administrated with gastrodin. The effects of gastrodin on rats were first assessed using electroencephalogram (EEG) recording, Racine classification, Morris water maze test, and histological staining. The levels of BDNF and NGF, and the activity of AMPK/PPARα were measured. Based on the results of EEG, behavior analyses, and histological staining, epileptic symptoms were significantly alleviated by gastrodin. Moreover, the administration of gastrodin also suppressed the levels of BDNF and NGF, and activated the AMPK/PPARα pathway. In conclusion, our results demonstrated that gastrodin contributed to the alleviation of pediatric epilepsy by activating AMPK/PPARα signaling transduction.
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Adenilato Quinase/metabolismo , Álcoois Benzílicos/farmacologia , Epilepsia/induzido quimicamente , Glucosídeos/farmacologia , Compostos de Lítio/química , PPAR alfa/metabolismo , Pilocarpina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Modelos Animais de Doenças , Eletroencefalografia , Ativação Enzimática , Epilepsia/fisiopatologia , Fator de Crescimento Neural/metabolismo , Pilocarpina/efeitos adversos , Pilocarpina/química , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacosRESUMO
OBJECTIVE: Vitamin D is an essential nutrient that regulates the activity of calcium and bone hormones throughout life; however, vitamin D levels in children, which is the most crucial period during human development, has not been established. METHODS: As the first descriptive study of serum vitamin D levels in children in Yunnan Province, we determined the serum vitamin D levels in children 0â4 years of age who underwent physical examinations at Kunming Children's Hospital, and the association between the serum vitamin D level and the calcium, phosphorus and alkaline levels. RESULTS: Vitamin D levels in children were highest in the summer months and lowest in the winter months. Vitamin D deficiency was more common in girls than boys. A social-economic effect was shown, as evidenced by the significantly higher serum vitamin D levels in children from the top five cities compared with the lower-ranked cities. Moreover, we also demonstrated a significant correlation between vitamin D and serum calcium levels. CONCLUSION: Our study suggested that sex and age affected the vitamin D levels of children, and a reasonable reference range in children 0-4 years of age in Yunnan Province was determined.
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Deficiência de Vitamina D , Vitamina D , Cálcio , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Deficiência de Vitamina D/diagnóstico , Deficiência de Vitamina D/epidemiologia , VitaminasRESUMO
Exosomes carrying microRNAs (miRNAs) mediate cell-to-cell communication, which play important roles in cancer growth and progression. However, the roles and molecular mechanisms of the miRNAs in the exosomes from carcinoma-associated fibroblasts (CAFs) are still not clear. The miRNA array showed that miR-3613-3p was an upregulated miRNA in CAFs exosomes. It was verified that miR-3613-3p was upregulated in exosomes from fibroblasts educated by TGF-ß1 and the fibroblasts from breast cancer tissues. Exosomal miR-3613-3p promoted breast cancer cell proliferation and metastasis. The cellular functions showed that miR-3613-3p downregulation in the CAFs exosomes suppressed cell proliferation and metastasis in breast cancer by targeting SOCS2 expression. The clinical data showed that miR-3613-3p levels were negatively related to SOCS2 expression in breast cancer tissues. In a conclusion, the study demonstrated that activated fibroblasts exosomes with high levels of miR-3613-3p played an oncogenic role in breast cancer cell survival and metastasis, which suggested that miR-3613-3p function as a therapeutic target.
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Neoplasias da Mama/genética , Carcinogênese/genética , MicroRNAs/genética , Proteínas Supressoras da Sinalização de Citocina/genética , Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Comunicação Celular/genética , Movimento Celular/genética , Proliferação de Células/genética , Exossomos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Metástase NeoplásicaRESUMO
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive accumulation of senile plaques, which are primarily composed of misfolded amyloid ß-peptide (Aß). Aß aggregates are believed to be a key factor in the pathogenesis of AD, affecting the nervous system in human body. The therapeutic potential of tea-derived polyphenolic compounds, (-)-epigallocatechin (EGC) and (-)-epicatechin-3-gallate (ECG), for AD was investigated by assessing their effects on the Cu2+/Zn2+-induced or self-assembled Aß40 aggregation using thioflavine T fluorescent spectrometry, inductively coupled plasma mass spectrometry, UV-Vis spectroscopy, transmission electron microscope, silver staining, immunohistochemistry, and immunofluorescence assays. EGC and ECG mildly bind to Cu2+ and Zn2+, and diminish the Cu2+- or Zn2+-induced or self-assembled Aß aggregates; they also modulate the Cu2+/Zn2+-Aß40 induced neurotoxicity on mouse neuroblastoma Neuro-2a cells by reducing the production of ROS. Metal chelating, hydrogen bonding or Van Der Waals force may drive the interaction between the polyphenolic compounds and Aß. The results demonstrate that green tea catechins EGC and ECG are able to alleviate the toxicity of Aß oligomers and fibrils. Particularly, ECG can cross the blood-brain barrier to reduce the Aß plaques in the brain of APP/PS1 mice, thereby protecting neurons from injuries. The results manifest the potential of green tea for preventing or ameliorating the symptoms of AD.
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Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/antagonistas & inibidores , Catequina/análogos & derivados , Agregação Patológica de Proteínas/tratamento farmacológico , Chá/química , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Catequina/química , Catequina/farmacologia , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Agregados Proteicos/efeitos dos fármacos , Agregação Patológica de Proteínas/metabolismo , Relação Estrutura-AtividadeRESUMO
The mammalian heart undergoes complex structural and functional remodeling to compensate for stresses such as pressure overload. While studies suggest that, at best, the adult mammalian heart is capable of very limited regeneration arising from the proliferation of existing cardiomyocytes, how myocardial stress affects endogenous cardiac regeneration or repair is unknown. To define the relationship between left ventricular afterload and cardiac repair, we induced left ventricle pressure overload in adult mice by constriction of the ascending aorta (AAC). One week following AAC, we normalized ventricular afterload in a subset of animals through removal of the aortic constriction (de-AAC). Subsequent monitoring of cardiomyocyte cell cycle activity via thymidine analog labeling revealed that an acute increase in ventricular afterload induced cardiomyocyte proliferation. Intriguingly, a release in ventricular overload (de-AAC) further increases cardiomyocyte proliferation. Following both AAC and de-AAC, thymidine analog-positive cardiomyocytes exhibited characteristics of newly generated cardiomyocytes, including single diploid nuclei and reduced cell size as compared to age-matched, sham-operated adult mouse myocytes. Notably, those smaller cardiomyocytes frequently resided alongside one another, consistent with local stimulation of cellular proliferation. Collectively, our data demonstrate that adult cardiomyocyte proliferation can be locally stimulated by an acute increase or decrease of ventricular pressure, and this mode of stimulation can be harnessed to promote cardiac repair.