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1.
Mol Neurobiol ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38965172

RESUMO

A pathological hallmark of Alzheimer's disease (AD) is the region-specific accumulation of the amyloid-beta protein (Aß), which triggers aberrant neuronal excitability, synaptic impairment, and progressive cognitive decline. Previous works have demonstrated that Aß pathology induced aberrant elevation in the levels and excessive enzymatic hydrolysis of voltage-gated sodium channel type 2 beta subunit (Navß2) in the brain of AD models, accompanied by alteration in excitability of hippocampal neurons, synaptic deficits, and subsequently, cognitive dysfunction. However, the mechanism is unclear. In this research, by employing cell models treated with toxic Aß1-42 and AD mice, the possible effects and potential mechanisms induced by Navß2. The results reveal that Aß1-42 induces remarkable increases in Navß2 intracellular domain (Navß2-ICD) and decreases in both BDNF exons and protein levels, as well as phosphorylated tropomyosin-related kinase B (pTrkB) expression in cells and mice, coupled with cognitive impairments, synaptic deficits, and aberrant neuronal excitability. Administration with exogenous Navß2-ICD further enhances these effects induced by Aß1-42, while interfering the generation of Navß2-ICD and/or complementing BDNF neutralize the Navß2-ICD-conducted effects. Luciferase reporter assay verifies that Navß2-ICD regulates BDNF transcription and expression by targeting its promoter. Collectively, our findings partially elucidate that abnormal enzymatic hydrolysis of Navß2 induced by Aß1-42-associated AD pathology leads to intracellular Navß2-ICD overload, which may responsible to abnormal neuronal excitability, synaptic deficit, and cognition dysfunction, through its transcriptional suppression on BDNF. Therefore, this work supplies novel evidences that Navß2 plays crucial roles in the occurrence and progression of cognitive impairment of AD by transcriptional regulatory activity of its cleaved ICD.

2.
Int J Clin Exp Pathol ; 17(4): 121-136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716350

RESUMO

Yang-deficiency constitution (YADC) is linked to a higher vulnerability to various diseases, such as cold coagulation and blood stasis (CCBS) syndrome and infertility. Endometrial hyperplastic processes (EHPs) are a leading cause of infertility in women and are characterized by CCBS. However, it remains unclear whether YADC is related to the development of EHPs. METHODS: We recruited 202 EHPs patients including 147 with YADC (YEH group) and 55 with non-YADC (NYEH group). Fecal samples were collected from 8 YEH patients and 3 NYEH patients and analyzed using 16S rRNA V3-V4 sequencing for gut microbiota analysis. We obtained constitution survey data and a differential gut microbiota dataset from the literature for further analysis. Bioinformatics analysis was conducted using gut microbiota-related genes from public databases. RESULTS: YADC was significantly more prevalent in EHPs than non-YADC (P < 0.001), suggesting it as a potential risk factor for EHPs occurrence (ORpopulation survey = 13.471; ORhealthy women = 5.173). The YEH group had higher levels of inflammation, estrogen, and tamoxifen-related flora compared to NYEH and healthy YADC groups. There was an interaction between inflammation, estrogen, differential flora, and EHPs-related genes, particularly the TNF gene (related to inflammation) and the EGFR gene (related to estrogen), which may play a crucial role in EHPs development. CONCLUSION: YEH individuals exhibit significant changes in their gut microbiota compared to NYEH and healthy YADC. The interaction between specific microbiota and host genes is believed to play a critical role in the progression of EHPs.

3.
Exp Brain Res ; 242(1): 205-224, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37994916

RESUMO

Traumatic brain injury (TBI) leads to disturbed brain discharge rhythm, elevated excitability, anxiety-like behaviors, and decreased learning and memory capabilities. Cognitive dysfunctions severely affect the quality of life and prognosis of TBI patients, requiring effective rehabilitation treatment. Evidence indicates that moderate exercise after brain injury decreases TBI-induced cognitive decline. However, the underlying mechanism remains unelucidated. Our results demonstrate that TBI causes cognitive impairment behavior abnormalities and overexpression of Nav1.1, Nav1.3 and Nav1.6 proteins inside the hippocampus of mice models. Three weeks of voluntary running wheel (RW) exercise treatments before or/and post-injury effectively redressed the aberrant changes caused by TBI. Additionally, a 10% exercise-conditioned medium helped recover cell viability, neuronal sodium current and expressions of Nav1.1, Nav1.3 and Nav1.6 proteins across cultured neurons after injury. Therefore, the results validate the neuroprotection induced by voluntary RW exercise treatment before or/and post-TBI. The RW exercise-induced improvement in cognitive behaviors and neuronal excitability could be associated with correcting the Nav1.1, Nav1.3, and Nav1.6 expression levels. The current study proves that voluntary exercise is an effective treatment strategy against TBI. The study also highlights novel potential targets for rehabilitating TBI, including the Navs proteins.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Canais de Sódio Disparados por Voltagem , Humanos , Camundongos , Animais , Qualidade de Vida , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/terapia , Cognição
4.
Toxicol Appl Pharmacol ; 481: 116732, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37871735

RESUMO

Metformin is commonly used, but approximately 20% of patients experience gastrointestinal intolerance, leading to medication discontinuation for unclear reasons and a lack of effective management strategies. In this study, the 18 fecal and blood samples were analyzed using 16S rRNA and mRNA transcriptome, respectively. These samples included 3 fecal and 4 blood from metformin-tolerant T2D patients before and after metformin treatment (T and Ta), 3 fecal and 5 blood from metformin-intolerant T2D patients before and after treatment (TS and TSa), and 6 fecal samples from healthy controls. The results showed that certain anti-inflammatory gut bacteria and gene, such as Barnesiella (p = 0.046), Parabacteroides goldsteinii (p = 0.016), and the gene JUND (p = 0.0002), exhibited higher levels in metformin-intolerant patients, and which decreased after metformin treatment (p < 0.05). This potentially invalidates patients' anti-inflammatory effect and intestinal mucus barrier protection, which may lead to alterations in intestinal permeability, decreased gut barrier function, and gastrointestinal symptoms, including diarrhea, bloating, and nausea. After metformin treatment, primary bile acids (PBAs) production species: Weissella confusa, Weissella paramesenteroides, Lactobacillus brevis, and Lactobacillus plantarum increased (p < 0.05). The species converting PBAs to secondary bile acids (SBAs): Parabacteroides distasonis decreased (p < 0.05). This might result in accumulation of PBAs, which also may lead to anti-inflammatory gene JUND and SQSTM1 downregulated. In conclusion, this study suggests that metformin intolerance may be attributed to a decrease in anti-inflammatory-related flora and genes, and also alterations in PBAs accumulation-related flora. These findings open up possibilities for future research targeting gut flora and host genes to prevent metformin intolerance.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Metformina , Humanos , Metformina/uso terapêutico , Microbioma Gastrointestinal/genética , Diabetes Mellitus Tipo 2/complicações , RNA Ribossômico 16S , Ácidos e Sais Biliares , Anti-Inflamatórios/uso terapêutico
5.
Biomimetics (Basel) ; 8(4)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37622948

RESUMO

With the rapid development of enabling technologies like VR and AR, we human beings are on the threshold of the ubiquitous human-centric intelligence era. 6G is believed to be an indispensable cornerstone for efficient interaction between humans and computers in this promising vision. 6G is supposed to boost many human-centric applications due to its unprecedented performance improvements compared to 5G and before. However, challenges are still to be addressed, including but not limited to the following six aspects: Terahertz and millimeter-wave communication, low latency and high reliability, energy efficiency, security, efficient edge computing and heterogeneity of services. It is a daunting job to fit traditional analytical methods into these problems due to the complex architecture and highly dynamic features of ubiquitous interactive 6G systems. Fortunately, deep learning can circumvent the interpretability issue and train tremendous neural network parameters, which build mapping relationships from neural network input (status and specific requirements of a 6G application) to neural network output (settings to satisfy the requirements). Deep learning methods can be an efficient alternative to traditional analytical methods or even conquer unresolvable predicaments of analytical methods. We review representative deep learning solutions to the aforementioned six aspects separately and focus on the principles of fitting a deep learning method into specific 6G issues. Based on this review, our main contributions are highlighted as follows. (i) We investigate the representative works in a systematic view and find out some important issues like the vital role of deep reinforcement learning in the 6G context. (ii) We point out solutions to the lack of training data in 6G communication context. (iii) We reveal the relationship between traditional analytical methods and deep learning, in terms of 6G applications. (iv) We identify some frequently used efficient techniques in deep-learning-based 6G solutions. Finally, we point out open problems and future directions.

6.
Ultrason Sonochem ; 97: 106475, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37321071

RESUMO

The objective of this research was to modify the crystal shape and size of poorly water-soluble drug ropivacaine, and to reveal the effects of polymeric additive and ultrasound on crystal nucleation and growth. Ropivacaine often grow as needle-like crystals extended along the a-axis and the shape was hardly controllable by altering solvent types and operating conditions for the crystallization process. We found that ropivacaine crystallized as block-like crystals when polyvinylpyrrolidone (PVP) was used. The control over crystal morphology by the additive was related to crystallization temperature, solute concentration, additive concentration, and molecular weight. SEM and AFM analyses were performed providing insights into crystal growth pattern and cavities on the surface induced by the polymeric additive. In ultrasound-assisted crystallization, the impacts of ultrasonic time, ultrasonic power, and additive concentration were investigated. The particles precipitated at extended ultrasonic time exhibited plate-like crystals with shorter aspect ratio. Combined use of polymeric additive and ultrasound led to rice-shaped crystals, which the average particle size was further decreased. The induction time measurement and single crystal growth experiments were carried out. The results suggested that PVP worked as strong nucleation and growth inhibitor. Molecular dynamics simulation was performed to explore the action mechanism of the polymer. The interaction energies between PVP and crystal faces were calculated, and mobility of the additive with different chain length in crystal-solution system was evaluated by mean square displacement. Based on the study, a possible mechanism for the morphological evolution of ropivacaine crystals assisted by PVP and ultrasound was proposed.

7.
Chin J Integr Med ; 29(6): 556-565, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37052766

RESUMO

Postoperative adhesion (PA) is currently one of the most unpleasant complications following surgical procedures. Researchers have developed several new strategies to alleviate the formation of PA to a great extent, but so far, no single measure or treatment can meet the expectations and requirements of clinical patients needing complete PA prevention. Chinese medicine (CM) has been widely used for thousands of years based on its remarkable efficacy and indispensable advantages CM treatments are gradually being accepted by modern medicine. Therefore, this review summarizes the formating process of PA and the efficacy and action mechanism of CM treatments, including their pharmacological effects, therapeutic mechanisms and advantages in PA prevention. We aim to improve the understanding of clinicians and researchers on CM prevention in the development of PA and promote the in-depth development and industrialization process of related drugs.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Aderências Teciduais/tratamento farmacológico , Aderências Teciduais/prevenção & controle , Desenvolvimento Industrial , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
8.
Nat Biomed Eng ; 7(1): 8-23, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36424464

RESUMO

The cell-surface glycoprotein CD98-a subunit of the LAT1/CD98 amino acid transporter-is an attractive target for cancer immunotherapies, but its widespread expression has hampered the development of CD98-targeting antibody therapeutics. Here we report that an anti-CD98 antibody, identified via the screening of phage-display libraries of CD98 single-chain variable fragments with mutated complementarity-determining regions, preserves the physiological function of CD98 and elicits broad-spectrum crystallizable-fragment (Fc)-mediated anti-tumour activity (requiring Fcγ receptors for immunoglobulins, macrophages, dendritic cells and CD8+ T cells, as well as other components of the innate and adaptive immune systems) in multiple xenograft and syngeneic tumour models established in CD98-humanized mice. We also show that a variant of the anti-CD98 antibody with pH-dependent binding, generated by solving the structure of the antibody-CD98 complex, displayed enhanced tumour-specific activity and pharmacokinetics. pH-dependent antibody variants targeting widely expressed antigens may lead to superior therapeutic outcomes.


Assuntos
Neoplasias , Anticorpos de Cadeia Única , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos , Concentração de Íons de Hidrogênio , Proteína-1 Reguladora de Fusão/imunologia
9.
Mol Ther Oncolytics ; 27: 256-269, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36458200

RESUMO

The clinical use of anti-EGFR antibody-based cancer therapy has been limited by antibody-EGFR binding in normal tissues, so developing pH-dependent anti-EGFR antibodies that selectively bind with EGFR in tumors-by taking advantage of the acidity of tumor microenvironment relative to normal tissues-may overcome these limitations. Here, we generated pH-dependent anti-EGFR antibodies with cross-species reactivity for human and mouse EGFR, and we demonstrate that pH-dependent antibodies exhibit tumor-selective binding by binding strongly to EGFR under acidic conditions (pH 6.5) but binding weakly under neutral (pH 7.4) conditions. Based on screening a non-immune human antibody library and antibody affinity maturation, we initially generated antibodies with cross-species reactivity for human and mouse EGFR. A structure model was subsequently constructed and interrogated for hotspots affecting pH-dependent binding, which supported development of a cross-reactive pH-dependent anti-EGFR antibody, G532. Compared with its non-pH-dependent antibody variant, G532 exhibits improved tumor selectivity, tumor penetration, and antitumor activity. Thus, beyond showing that pH-dependent anti-EGFR antibodies can overcome multiple limitations with antibody-based cancer therapies targeting EGFR, our study illustrates a structure-guided antibody-antigen binding pH-dependency engineering strategy to enhance antibody tumor selectivity and tumor penetration, which can inform the future development of antibody-based cancer therapies targeting other ubiquitously expressed molecules.

10.
Neural Plast ; 2022: 3995227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406589

RESUMO

Voltage-gated sodium channel beta 2 (Nav2.2 or Navß2, coded by SCN2B mRNA), a gene involved in maintaining normal physiological functions of the prefrontal cortex and hippocampus, might be associated with prefrontal cortex aging and memory decline. This study investigated the effects of Navß2 in amyloid-ß 1-42- (Aß1-42-) induced neural injury model and the potential underlying molecular mechanism. The results showed that Navß2 knockdown restored neuronal viability of Aß1-42-induced injury in neurons; increased the contents of brain-derived neurotrophic factor (BDNF), enzyme neprilysin (NEP) protein, and NEP enzyme activity; and effectively altered the proportions of the amyloid precursor protein (APP) metabolites including Aß42, sAPPα, and sAPPß, thus ameliorating cognitive dysfunction. This may be achieved through regulating NEP transcription and APP metabolism, accelerating Aß degradation, alleviating neuronal impairment, and regulating BDNF-related signal pathways to repair neuronal synaptic efficiency. This study provides novel evidence indicating that Navß2 plays crucial roles in the repair of neuronal injury induced by Aß1-42 both in vivo and in vitro.


Assuntos
Disfunção Cognitiva , Canais de Sódio Disparados por Voltagem , Humanos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Neurônios/metabolismo , Canais de Sódio Disparados por Voltagem/metabolismo , Neprilisina/genética , Neprilisina/metabolismo , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/metabolismo
11.
J Clin Med ; 11(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36233730

RESUMO

BACKGROUND: The presence of the blood-brain barrier (BBB) uniquely distinguishes the brain from other organs, and various brain pathologies, including cancer, can disrupt or breach the BBB. The specific implications of BBB alterations in glioma have not been sufficiently clarified. METHODS: In this study, statistical analysis of the TCGA pan-glioma dataset and four other validation cohorts was used to investigate the infiltration of BBB constituent cells (endothelial cells, pericytes and astrocytes) in the glioma tumor microenvironment (TME). RESULTS: We found that the infiltration proportions of the three BBB constituent cell types were highly collinear, which implied alteration of the BBB. Hence, we developed an index, the BBB score, which is calculated based on the infiltration proportion of BBB constituent cells. Furthermore, we observed that patients with higher BBB scores were more likely to be diagnosed with more malignant entities in the TCGA database according to significant molecular features, such as IDH mutation status and 1p/19q deletion. The BBB score was also strikingly positively correlated with WHO grade in other cohorts. More importantly, a higher BBB score correlated with shorter survival time and unfavorable prognosis in glioma patients. Finally, we showed that TME-related pathways may regulate BBB alterations and that coinhibitory immune checkpoints were enriched in samples with higher BBB scores. CONCLUSIONS: We showed that TME-related pathways may regulate BBB alterations and that coinhibitory immune checkpoints were enriched in samples with higher BBB scores. Assessing BBB alterations may help elucidate the complex role of the glioma TME and suggest new combination treatment strategies.

12.
J Tradit Chin Med ; 42(1): 96-101, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35294128

RESUMO

OBJECTIVE: Yang-deficiency constitution (YADC) is a common unbalanced constitution that predisposes individuals to certain diseases. However, not all people with YADC manifest develop diseases. This calls for delineation of the underlying molecular mechanisms. Previous studies suggested that the gut microbiota and gene differential expression should be considered. METHODS: In the present study, we compared profiles of gut microbiota between four healthy YADC individuals and those of five healthy balanced constitution (BC) counterparts, based on 16S rRNA gene sequence analysis. Furthermore, YADC relevant genes identified by comparing 62 healthy YADC and 58 healthy BC individuals in total to perform intersection analysis, functional clustering and pathway enrichment analyses. RESULTS: The levels of harmful gut microbiota (Prevotellaceae, LDA score > 4.0, P = 0.0141) and beneficial gut microbiota (Ruminococcaceae, LDA score > 4.0, P = 0.0025, Faecalibacterium, LDA score > 4.0, P = 0.0484) were both elevated in healthy YADC individuals. Also, we found that the specific metabolic pathway with 2, 6-Dichloro-p-hydroquinone 1, 2-Dioxygenase (PcpA) as the core in gut microbiota and the glutathione transferase activity has been enriched by YADC relevant genes in healthy YADC individuals were both responsible for the detoxification of halogenated aromatic hydrocarbon substances. CONCLUSIONS: Both beneficial and harmful factors had been detected in healthy YADC individuals, functionally, they may have triggered homeostasis to maintain the health of individuals with YADC. The homeostasis may be maintained by beneficial and harmful factors from gut flora and genes. Future studies are expected to focus on halogenated aromatic hydrocarbons and their detoxification processes.


Assuntos
Microbioma Gastrointestinal , Homeostase , Humanos , RNA Ribossômico 16S/genética , Deficiência da Energia Yang
13.
Aging (Albany NY) ; 13(5): 6702-6711, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33675295

RESUMO

OBJECTIVE: Obesity has gained attention among patients with inflammatory bowel disease (IBD). The impact of visceral obesity on chronic constipation, inflammation, immune function and cognition after diagnosis of IBD is still unknown. METHODS: This is a cross-sectional study of 150 IBD patients. Patients' visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were measured and were grouped according to visceral obesity. The potential impact of visceral obesity on cognitive function were evaluated using Mini-Mental State Examination. We evaluated patients' incidence of chronic constipation, levels of interleukin-6 (IL-6), T cells and body mass index in two groups. RESULTS: The prevalence of visceral obesity was 51% (37 out of 72) for Crohn's disease (CD) patients and 26% for UC patients (20 out of 78 patients). CD patients with visceral obesity has higher incidence of chronic constipation (81% vs. 57%, P = 0.028), higher IL-6 levels (15.28 pg/ml vs. 9.429 pg/ml, P = 0.007) and lower CD4+ T cells (32.7% vs. 44.0%, P < 0.001). VAT/SAT ratio is associated with BMI (P < 0.001). CONCLUSIONS: IBD patients had high risks of visceral obesity. CD Patients with visceral obesity had higher prevalence of chronic constipation, higher inflammation levels, decreased immune function.


Assuntos
Doenças Inflamatórias Intestinais/complicações , Obesidade Abdominal/complicações , Adulto , Idoso , Índice de Massa Corporal , Linfócitos T CD4-Positivos/metabolismo , Doença Crônica , Disfunção Cognitiva/diagnóstico , Constipação Intestinal/complicações , Estudos Transversais , Feminino , Humanos , Interleucina-6/sangue , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Adulto Jovem
14.
Pharm Biol ; 59(1): 311-320, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33784489

RESUMO

CONTEXT: Current medicine for Alzheimer's disease (AD) cannot effectively reverse or block nerve injury. Traditional Chinese Medicine practice and research imply Aconiti lateralis Radix Praeparata (Fuzi) may meet this goal. OBJECTIVE: Analysing the anti-AD effect of Fuzi and its potential molecular mechanism. MATERIALS AND METHODS: AD model cells were treated with Fuzi in 0-300 mg/mL for 24 h in 37 °C. The cell viability (CV) and length of cell projections (LCP) for each group were observed, analysed, and standardised using control as a baseline (CVs and LCPs). The Fuzi and AD relevant genes were identified basing on databases, and the molecular mechanism of Fuzi anti-AD was predicted by network analysis. RESULTS: Experiment results showed that Fuzi in 0.4 mg/mL boosted LCP (LCPs = 1.2533, p ≤ 0.05), and in 1.6-100 mg/mL increased CV (CVs from 1.1673 to 1.3321, p ≤ 0.05). Bioinformatics analysis found 17 Fuzi target genes (relevant scores ≥ 20), showing strong AD relevant signals (RMS_p ≤ 0.05, related scores ≥ 5), enriched in the pathways regulating axon growth, synaptic plasticity, cell survival, proliferation, apoptosis, and death (p ≤ 0.05). Especially, GRIN1 and MAPK1 interacted with APP protein and located in the key point of the "Alzheimer's disease" pathway. DISCUSSION AND CONCLUSIONS: These results suggest that Fuzi may have therapeutic and prevention potential in AD, and GRIN1 and MAPK1 may be the core of the pathways of the Fuzi anti-AD process. Fuzi should be studied more extensively, especially for the prevention of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Aconitum/química , Doença de Alzheimer/fisiopatologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Diterpenos/administração & dosagem , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA
15.
J Agric Food Chem ; 67(47): 13061-13072, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31738551

RESUMO

In this study, we purified three new sesquiterpenyl epoxy-cyclohexenoid (SEC) analogues, arthrobotrisin D (11) and its two derivatives, from nematode-trapping fungus Arthrobotrys oligospora. Our results revealed that arthrobotrisin type SEC metabolites could be detected in all the test fungal strains from geographically distinct regions grown on different nutrient media, indicative of unique diagnostic character as chemical indicators for A. oligospora. The time course designs over short-term intervals of the fungus under direct contact and indirect contact with living or dead nematodes revealed that arthrobotrisin B and D (6 and 11) displayed significant relationships (positive or negative correlation) with fungal saprophytic and pathogenic stages during a nematode predation event. Interestingly, fungus on nutrient-limiting medium conducive to fungal trap formation could rapidly drop the concentration levels of arthrobotrisins B and D within 6 h when dead nematodes were around, in great contrast to that for living nematodes. Moreover, only in the fungal strain under direct contact with living dominant soil bacteria, arthrobotrisins B and D exhibited significant increase in amounts. Among them, the new SEC, arthrobotrisin D (11) was found to be a key unique metabolic signal for fungal colony growth and fungal interaction with prey and bacteria. Our study suggested that chemical analysis of SEC metabolites in A. oligospora provides a window into the fungal growth status and much valuable information about ecological environments associated with the nematode infections.


Assuntos
Ascomicetos/química , Compostos de Epóxi/química , Nematoides/microbiologia , Sesquiterpenos/química , Animais , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Compostos de Epóxi/metabolismo , Estrutura Molecular , Sesquiterpenos/metabolismo
16.
Eur J Pharmacol ; 858: 172477, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31228450

RESUMO

The extracts of Phellodendron amurense (P. amurense) have been shown to contain many active ingredients e.g. flavone glycosides and to exert a wide range of physiological activities including anti-tumor activity. However, the effects of phellamurin (Phe), a plant flavonone glycoside from the leaves of P. amurense, on osteosarcoma (OS) have never been reported. The effects of Phe on cell viability and apoptosis were evaluated by MTT assay and flow cytometry analysis, respectively. Western blot analysis was performed to detect the protein levels of phosphorylated phosphatidylinositol 3 kinase (PI3K) (p-PI3K), phosphorylated protein kinase B (AKT) (p-AKT), AKT, phosphorylated mammalian target of rapamycin (mTOR) (p-mTOR), and mTOR. We found that Phe suppressed the viability and promoted apoptosis in OS cells in a dose-dependent manner. Notably, Phe repressed the PI3K/AKT/mTOR pathway in OS cells. LY294002 effectively inhibited the PI3K/AKT/mTOR signaling pathway, repressed cell viability and induced apoptosis in OS cells. Activation of PI3K/AKT/mTOR pathway by 740Y-P abolished the effects of Phe on the viability and apoptosis of OS cells. We also found that Phe repressed OS tumor growth and inhibited the PI3K/AKT/mTOR pathway in vivo. In conclusion, Phe suppressed the viability and induced apoptosis in OS cells, at least, partially by inhibiting the PI3K/AKT/mTOR pathway. Our study suggested that Phe might be a new and potential chemotherapeutic agent for the treatment of OS.


Assuntos
Antineoplásicos/farmacologia , Flavonoides/farmacologia , Osteossarcoma/patologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Int J Biochem Cell Biol ; 110: 130-139, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30822557

RESUMO

STAT3ß is an isoform of STAT3 (signal transducer and activator of transcription 3) that differs from the STAT3α isoform by the replacement of the C-terminal 55 amino acid residues with 7 specific residues. The constitutive activation of STAT3α plays a pivotal role in the activation of oncogenic pathways, such as cell proliferation, maturation and survival, while STAT3ß is often referred to as a dominant-negative regulator of cancer. STAT3ß reveals a "spongy cushion" effect through its cooperation with STAT3α or forms a ternary complex with other co-activators. Especially in tumour cells, relatively high levels of STAT3ß lead to some favourable changes. However, there are still many mechanisms that have not been clearly explained in contrast to STAT3α, such as STAT3ß nuclear retention, more stable heterodimers and the prolonged Y705 phosphorylation. In addition to its transcriptional activities, STAT3ß may also function in the cytosol with respect to the mitochondria, cytoskeleton rearrangements and metastasis of cancer cells. In this review, we summarize the mechanisms that underlie the unique roles of STAT3ß combined with total STAT3 to enlighten and draw the attention of researchers studying STAT3 and discuss some interesting questions that warrant answers.


Assuntos
Fator de Transcrição STAT3 , Animais , Humanos , Neoplasias/genética , Neoplasias/patologia , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Fator de Transcrição STAT3/química , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
18.
Int J Biol Macromol ; 128: 574-582, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30710584

RESUMO

Multidrug resistance (MDR) is a critical reason of cancer chemotherapy failure. Ribophorin II (RPN2) has emerged as a vital regulator of MDR in multiple cancers including gastric cancer (GC). However, the roles and molecular mechanisms of RPN2 in MDR have not been well featured till now. The present study aimed to explore the roles and molecular mechanisms of RPN2 in MDR of drug-resistant GC cells. Results showed that the expressions of RPN2, multidrug resistance 1 (MDR1), and ATP binding cassette subfamily G member 2 (ABCG2) were upregulated in SGC7901/DDP and SGC7901/VCR cells. Knockdown of RPN2 alleviated MDR through downregulating MDR1 and ABCG2 expressions in SGC7901/DDP and SGC7901/VCR cells. RPN2 depletion inhibited the activation of MEK/ERK pathway. RPN2 overexpression enhanced MDR by upregulating P-glycoprotein (P-gp) and ABCG2 protein expressions in SGC7901/DDP or SGC7901/VCR cells, while this effect of RPN2 was abrogated by ERK knockdown or treatment with ERK inhibitor PD98059. Our findings suggested that RPN2 potentiated P-gp- and ABCG2-mediated MDR via activating MEK/ERK pathway in GC, hinting the critical values of RPN2 in ameliorating MDR and providing a promising target for GC therapy.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Resistência a Múltiplos Medicamentos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas de Membrana/metabolismo , Neoplasias Gástricas/patologia , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Regulação para Cima
19.
Onco Targets Ther ; 12: 599-607, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30697057

RESUMO

BACKGROUND: miR-4262 was identified as a tumor promoter in several cancers, but its exact role in gastric carcinoma is still largely unknown. METHODS: The expression of miR-4262 was detected in gastric cancer tissues. Different concentrations of miR-4262 mimic and miR-4262 antagomir were respectively transfected into primary gastric carcinoma cells. After incubation for 72 h, the overexpression efficiencies were confirmed by qPCR, cell proliferation was detected with the CCK-8 assay, cell apoptosis was detected by using the PI/Annexin V Cell Apoptosis Kit, and cell invasion was detected with the Transwell invasion assay. The molecular mechanisms underlying the action of miR-4262 in gastric carcinoma cells were also explored. RESULTS: In this study, we found that miR-4262 was significantly downregulated in gastric tissue from gastric cancer patients compared with that from the control group. Moreover, the level of miR-4262 was significantly lower in advanced gastric carcinoma. Additionally, lower level of miR-4262 was correlated with poorer prognosis and lower survival rate in gastric cancer patients. Then, different concentrations of miR-4262 mimic and miR-4262 antagomir were transfected into primary gastric carcinoma cells, respectively. The results showed that miR-4262 mimic suppressed proliferation and invasion and promoted cell apoptosis in a dose-dependent manner in gastric carcinoma cells. In contrast, miR-4262 antagomir increased proliferation and invasion and decreased cell apoptosis in a dose-dependent manner in gastric carcinoma cells. Furthermore, miR-4262 could directly target and suppress the expression of the proto-oncogene CD163. CONCLUSION: Our findings indicate that lower level of miR-4262 predicts poorer prognosis in gastric patients, and miR-4262 can target proto-oncogene CD163 to suppress gastric cancer cell proliferation and invasion.

20.
Eur J Pharmacol ; 818: 364-370, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29126793

RESUMO

Notch signaling pathway has been demonstrated to mediate radioresistance of several tumors. Our study aims to explore the function of Notch1/HES1 pathway in the radioresistance of colorectal cancer (CRC). The results demonstrated that expressions of Notch1 and Hes1 were up-regulated with the increasing irradiation dose. DAPT (N-[(3,5-difluorophenacetyl)acety1]-L-alanyl-2-phenyl]glycine-1,1-dimethylethyl ester) or si-Notch1 reduced expressions of Notch1 and Hes1, exacerbated irradiation-induced cell proliferation inhibition, and improved radiosensitivity of CRC cells. Moreover, DAPT or si-Notch1 increased radiation-induced DNA damage and attenuated radiation-triggered DNA-PK activity. Furthermore, xenograft in nude mice demonstrated that co-treated with DAPT and irradiation could inhibited tumor growth additively in vivo. Taken together, inhibition of Notch1/Hes1 signaling pathway enhances radiosensitivity of CRC cells, providing a potential therapeutic target to improve the therapeutic effect of radiotherapy for CRC patients.


Assuntos
Neoplasias Colorretais/patologia , Tolerância a Radiação/efeitos dos fármacos , Tolerância a Radiação/genética , Receptor Notch1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Transcrição HES-1/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Transformação Celular Neoplásica , Dipeptídeos/farmacologia , Células HT29 , Humanos , Camundongos , RNA Interferente Pequeno/genética
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