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There is growing evidence that extracellular vesicles (EVs) play a functional role in tissue repair and anti-aging by transferring the contents of donor cells to recipient cells. We hypothesized that Dauer (C. elegans), known as "ageless" nematodes, can also secrete extracellular vesicles and influence the lifespan of C. elegans. Here, we isolated EVs of dauer larvae (dauer EVs). Dauer EVs were characterized using transmission electron microscopy, nanoparticle tracking analysis (NTA), and Western blot analysis. Wild-type C. elegans were fed in the presence or absence of dauer EVs and tested for a range of phenotypes, including longevity, mobility and reproductive capacity. Results showed that dauer EVs increased the average lifespan of nematodes by 15.74%, improved mobility, slowed age-related pigmentation as well as body length, and reduced the accumulation of reactive oxygen species and lipids, while not impairing nematode reproductive capacity. These findings suggest that dauer EVs can extend the lifespan of C. elegans as well as the healthy lifespan by reducing ROS accumulation, with potential anti-aging capacity.
Assuntos
Proteínas de Caenorhabditis elegans , Vesículas Extracelulares , Animais , Caenorhabditis elegans/genética , Larva , Envelhecimento , Proteínas de Caenorhabditis elegans/genética , Longevidade/genéticaRESUMO
BACKGROUND: Bacterial outer membrane vesicles have gained increasing attention for its antitumor effect and application in drug delivery. However, the bacterial membrane vesicles (MVs) that are secreted by Gram-positive bacteria are rarely mentioned. Bifidobacterium has a certain anti-tumor effect, but there is a certain risk when injected into human body. Here we investigated the potential of Bifidobacterium-derived membrane vesicles (B-MVs) as therapeutic agents to treat triple-negative breast cancer. METHODS AND RESULTS: Firstly, we discovered that Bifidobacterium can produce B-MVs and isolated them. In vivo, we found that B-MVs can inhibit tumor growth in mice and the mice were in good state. H&E staining displayed extensive apoptotic cells in tumor tissues. Western blotting and immunohistochemistry showed that B-MVs increased the expression of Bax, while decreased the expression of Bcl-2. These results suggested that B-MVs may induce apoptosis of tumor cells in vivo. Furthermore, to further confirm this phenomenon, we conducted experiments in vitro. Hoechst 33,258 staining assay, flow cytometry and western blotting also demonstrated B-MVs promoted cell apoptosis in vitro. CONCLUSIONS: We speculate B-MVs may inhibit tumor growth by inducing tumor cell apoptosis in triple-negative breast cancer, which provided a new direction in the treatment of TNBC.
Assuntos
Neoplasias de Mama Triplo Negativas , Camundongos , Humanos , Animais , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Apoptose , Citometria de Fluxo , Linhagem Celular TumoralRESUMO
Purpose: Patients with non-muscle invasive bladder cancer (NMIBC) have a high possibility of recurrence after surgery. We aimed to assess the factors associated with tumor recurrence and to construct a nomogram model that can contribute to personalized treatment plans of each patient. Methods: 496 patients with primary bladder cancer (BC) from 2 centers were retrospectively analyzed. Preoperative neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and traditional clinical parameters were collected, then using univariate and multivariate Cox regression analysis to find out the independent risk factors associated with tumor recurrence among them, and then these independent factors were incorporated into the nomogram model. The internal calibration curves and the external calibration curves were used to verify their usefulness. Results: In the training cohort, 150 patients (43.1%) experienced recurrence. After Cox regression analysis, the independent risk factors affecting recurrence-free survival (RFS) were tumor grade, immediate postoperative instillation therapy (IPPIT), NLR, and SII. These factors were used to construct a model to predict RFS 1, 2, 3, and 5 years of NMIBC patients after surgery. And then, we found that the constructed model outperforms the conventional model in terms of accuracy and predictability, the results were verified by statistical tests. Conclusion: Preoperative inflammatory response markers have a predictive value for postoperative recurrence in patients with NMIBC. The constructed nomogram model can be helpful in guiding personalized clinical evaluation and subsequent treatment.
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Excessive chlorpyrifos (CPF) in the environment causes toxicity to nontarget organisms by triggering oxidative stress. Phosphatase and tensin homolog deleted on chromosome ten (PTEN) plays an important role in controlling apoptosis and necrosis by negatively regulating the phosphatidylinositol 3-kinase/threonine kinase (PI3K/AKT) pathway. However, the effects of different concentrations of CPF on grass fish liver cell injury and the role of the ROS/PTEN/PI3K/AKT axis remain poorly understood. In this study, L8824 cells treated with different concentrations of CPF (0, 40, 60, or 80 µM) were used as the research object. The results showed that the median inhibitory concentration (IC50) was 112.226 µM. As the CPF concentrations increased, the ROS and MDA levels increased, and the T-AOC levels and SOD/GPx/GST activities decreased. As PTEN expression increased, PI3K/AKT, BCL-2, and Caspase-8 expression dramatically decreased. Conversely, RIPK1/RIPK3/MLKL and Bax/Cyt-c/Caspase-3 expression increased. Additionally, necroptosis increased in a dose-dependent manner, while apoptosis first increased and then decreased. In conclusion, our study showed that CPF could trigger oxidative stress and induce apoptosis and necroptosis in fish liver cells by regulating the ROS/PTEN/PI3K/AKT axis, and the type of damage induced was dose-dependent. These results are meaningful for toxicological studies of CPF and efforts to protect the ecosystem.
Assuntos
Clorpirifos , Animais , Apoptose , Clorpirifos/toxicidade , Ecossistema , Necroptose , Fosfatidilinositol 3-Quinase , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais , TreoninaRESUMO
Graphene is an ideal candidate for the development of solid state nanopores due to its thickness at the atomic scale and its high chemical and mechanical stabilities. A facile method was adopted to prepare single graphene nanopore supported by PET membrane (G/PET nanopore) within the three steps assisted by the swift heavy ion irradiation and asymmetric etching technology. The inversion of the ion rectification effect was confirmed in G/PET nanopore while comparing with bare PET nanopore in KCl electrolyte solution. By modifying the wall charge state of PET conical nanopore with hydrochloric acid from negative to positive, the ion rectification effect of G/PET nanopore was found to be greatly enhanced and the large rectification ratio up to 190 was obtained during this work. Moreover, the high ionic flux and high ion separation efficiency was also observed in the G/PET nanopore system. By comparing the "on" and "off" state conductance of G/PET nanopore while immersed in the solution with pH value lower than the isoelectric point of the etched PET (IEP, pH = 3.8), the voltage dependence of the off conductance was established and it was confirmed that the large rectification effect was strongly dependent on the particularly low off conductance at higher applied voltage.