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1.
Foods ; 13(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38672844

RESUMO

Colorectal carcinoma (CRC) is a major global health concern, with cancer metastasis being the main cause of patient mortality, and current CRC treatments are challenged by drug resistance. Although natural compounds, especially in foods like hawthorn proanthocyanidin extract (HPOE), have good anticancer activity, their effects on CRC metastasis remain unknown. Therefore, our objective was to investigate the impact and potential mechanisms of HPOE on the movement and infiltration of cells in the HCT116 CRC cells. Firstly, scratch-healing experiments confirmed the anti-migratory and anti-invasive capabilities of HPOE. Then, network pharmacology identified 16 possible targets, including MMP-9. Subsequently, RT-qPCR and Western blotting experiments confirmed that HPOE downregulated epithelial-mesenchymal transition-related factors (N-cadherin and MMP-9) and inhibited Wnt/ß-catenin pathway activation. Finally, these results were experimentally validated using the Wnt pathway activator Licl and inhibitor XAV939. It was confirmed that HPOE had a certain inhibitory effect on the activation of the Wnt signaling pathway caused by the activator Licl and could enhance the inhibitory effect of the inhibitor XAV939. Our findings provide a basis for developing functional foods or dietary supplements, especially positioning HPOE as a functional food raw material for adjuvant treatment of CRC, given its ability to inhibit metastasis through the Wnt/ß-catenin pathway.

2.
J Adv Res ; 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38565404

RESUMO

BACKGROUND: Glioblastoma (GBM) is the most common malignant tumour of the central nervous system. Despite recent advances in multimodal GBM therapy incorporating surgery, radiotherapy, systemic therapy (chemotherapy, targeted therapy), and supportive care, the overall survival (OS) remains poor, and long-term survival is rare. Currently, the primary obstacles hindering the effectiveness of GBM treatment are still the blood-brain barrier and tumor heterogeneity. In light of its substantial advantages over conventional therapies, such as strong penetrative ability and minimal side effects, low-frequency magnetic fields (LF-MFs) therapy has gradually caught the attention of scientists. AIM OF REVIEW: In this review, we shed the light on the current status of applying LF-MFs in the treatment of GBM. We specifically emphasize our current understanding of the mechanisms by which LF-MFs mediate anticancer effects and the challenges faced by LF-MFs in treating GBM cells. Furthermore, we discuss the prospective applications of magnetic field therapy in the future treatment of GBM. Key scientific concepts of review: The review explores the current progress on the use of LF-MFs in the treatment of GBM with a special focus on the potential underlying mechanisms of LF-MFs in anticancer effects. Additionally, we also discussed the complex magnetic field features and biological characteristics related to magnetic bioeffects. Finally, we proposed a promising magnetic field treatment strategy for future applications in GBM therapy.

3.
Eur J Cancer ; 199: 113528, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218157

RESUMO

BACKGROUND: Extent of resection (EOR) in glioma contributes to longer survival. The purpose of NCT01479686 was to prove whether intraoperative magnetic resonance imaging (iMRI) increases EOR in glioma surgery and benefit survival. METHODS: Patients were randomized (1:1) to receive the iMRI (n = 161) or the conventional neuronavigation (n = 160). The primary endpoint was gross total resection (GTR); secondary outcomes reported were progression-free survival (PFS), overall survival (OS), and safety. RESULTS: 188 high-grade gliomas (HGGs) and 133 low-grade gliomas (LGGs) were enrolled. GTR was 83.85% in the iMRI group vs. 50.00% in the control group (P < 0.0001). In 321 patients, the median PFS (mPFS) was 65.12 months in the iMRI group and 61.01 months in the control group (P = 0.0202). For HGGs, mPFS was improved in the iMRI group (19.32 vs. 13.34 months, P = 0.0015), and a trend of superior OS compared with control was observed (29.73 vs. 25.33 months, P = 0.1233). In the predefined eloquent area HGG subgroup, mPFS, and mOS were 20.47 months and 33.58 months in the iMRI vs. 12.21 months and 21.16 months in the control group (P = 0.0098; P = 0.0375, respectively). From the exploratory analyses of HGGs, residual tumor volume (TV) < 1.0 cm3 decreased the risk of survival (mPFS: 18.99 vs. 9.43 months, P = 0.0055; mOS: 29.77 vs. 18.10 months, P = 0.0042). LGGs with preoperative (pre-OP) TV > 43.1 cm3 and postoperative (post-OP) TV > 4.6 cm3 showed worse OS (P= 0.0117) CONCLUSIONS: It showed that iMRI significantly increased EOR and indicated survival benefits for HGGs, particularly eloquent HGGs. Residual TV in either HGGs or LGGs is a prognostic factor for survival.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Estudos Retrospectivos , Monitorização Intraoperatória/métodos , Glioma/diagnóstico por imagem , Glioma/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/métodos , Imageamento por Ressonância Magnética/métodos
4.
Discov Oncol ; 14(1): 183, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845388

RESUMO

PURPOSE: In the past decade, there has been little progress in the treatment of malignant glioma. Recently, oncolytic virus has made great progress in glioma treatment, and a number of clinical trials have shown their potential of prolonging the survival time of glioma patients. Our objective is to evaluate effectiveness and safety of oncolytic virus (OV) in malignant glioma treatment. METHODOLOGY: Based upon PRISMA, we collected relevant published clinical trials by searching medical databases up to January 16, 2023, applying the language restrictions in English and Chinese. We cross-searched the terms: 'glioma', 'glioblastoma', 'oncolytic viruses', 'oncolytic virotherapy' with filter 'clinical trial'. Two researchers independently extracted the data regarding case definitions, published years, trial phase, characteristics of patients, administration of drug, overall survival (OS), and adverse events. RESULTS: 19 published clinical trials in OV treatment of malignant glioma were included in the further systematic review analysis. None of them induced irresistible adverse effects attributing to OV treatment, median overall survival varied from 3.25 to 20.2 months after treatments. According to trials providing patient's detailed molecular diagnosis, we find that the effectiveness of OV treatment has no significant difference in patients with different IDH or MGMT status. CONCLUSIONS: Current clinical trials have initially shown the potential of oncolytic virotherapy as a new treatment for malignant glioma. Besides development of virus types, the strategy of OV use is an urgent problem to be solved in future clinical application, such as repeated administrations, innovative drug delivery systems, and biomarkers.

5.
Neurooncol Adv ; 5(1): vdad117, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841695

RESUMO

Background: The development of new therapies for malignant gliomas has been stagnant for decades. Through the promising outcomes in clinical trials of oncolytic virotherapy, there is now a glimmer of hope in addressing this situation. To further enhance the antitumor immune response of oncolytic viruses, we have equipped a modified oncolytic adenovirus (oAds) with a recombinant interferon-like gene (YSCH-01) and conducted a comprehensive evaluation of the safety and efficacy of this modification compared to existing treatments. Methods: To assess the safety of YSCH-01, we administered the oAds intracranially to Syrian hamsters, which are susceptible to adenovirus. The efficacy of YSCH-01 in targeting glioma was evaluated through in vitro and in vivo experiments utilizing various human glioma cell lines. Furthermore, we employed a patient-derived xenograft model of recurrent glioblastoma to test the effectiveness of YSCH-01 against temozolomide. Results: By modifying the E1A and adding survivin promoter, the oAds have demonstrated remarkable safety and an impressive ability to selectively target tumor cells. In animal models, YSCH-01 exhibited potent therapeutic efficacy, particularly in terms of its distant effects. Additionally, YSCH-01 remains effective in inhibiting the recurrent GBM patient-derived xenograft model. Conclusions: Our initial findings confirm that a double-modified oncolytic adenovirus armed with a recombinant interferon-like gene is both safe and effective in the treatment of malignant glioma. Furthermore, when utilized in combination with a targeted therapy gene strategy, these oAds exhibit a more profound effect in tumor therapy and an enhanced ability to inhibit tumor growth at remote sites.

7.
Materials (Basel) ; 16(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37569991

RESUMO

The current work reveals the influence of loading parameters on the crack growth behavior of a Zr/Ti/steel composite plate with a crack normal to the interface by using an experiment and the finite element method. The Chaboche model was first used to study cyclic plastic evolution in composite materials. The results reveal that an increase in Fmax, Fm, and Fa can promote da/dN; meanwhile, an increase in R will reduce da/dN. The plastic strain accumulation results indicate that Fm mainly contributes to the tensile strain and compressive stress after the first cycle. Additionally, Fa increases the stress range and compression stress and greatly improves the plastic strain accumulation degree in subsequent loading cycles. The Fmax can significantly increase the stress amplitude and plastic strain accumulation level. When R increases, the plastic strain accumulation increases a little, but the stress amplitude and compression stress decrease greatly. Furthermore, it is also found that the elastic-plastic mismatch also affects the plastic evolution, that is, strengthening or weakening the effect of the loading parameters.

8.
Food Res Int ; 169: 112942, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37254366

RESUMO

Limited evidence suggests that the abundance of antioxidant polyphenols in dry red wine (DRW) may prevent cardiovascular diseases, a benefit likely attributed to abundant antioxidant polyphenols present in DRW. Here, we examined the anti-atherosclerotic effect of Cabernet Sauvignon DRW (CSDRW) in a mouse model of atherosclerosis (AS) using metabolomic profiling and molecular techniques. Oral administration of CSDRW reduced atherosclerotic lesion size in ApoE-/- mice, alleviated hyperlipidemia, ameliorated hepatic lipid accumulation mediated by AMPK activation, and promoted lipid metabolism via PPARγ-LXR-α-ABCA1 pathway regulation. CSDRW increased the relative abundance of beneficial gut microbiota, including Bacteroidetes, Verrucomicrobiota, and Akkermansiaceae. Metabolic analysis using liquid chromatography-tandem mass spectrometry revealed that CSDRW contained various polyphenols, including flavanol, phenolic acid, flavonol, and resveratrol, which possibly mediate the beneficial effects in AS by reducing inflammation, restoring normal endothelial function, regulating hepatic lipid metabolism, and modulating gut microbiota composition.


Assuntos
Aterosclerose , Microbioma Gastrointestinal , Vinho , Camundongos , Animais , Proteínas Quinases Ativadas por AMP , Vinho/análise , Fosforilação , Antioxidantes/farmacologia , Antioxidantes/análise , Polifenóis/farmacologia , Polifenóis/análise , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Aterosclerose/patologia , Inflamação
10.
J Agric Food Chem ; 71(17): 6635-6649, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37083411

RESUMO

Triterpenoids derived from natural products can exert antihyperuricemic effects. Here, we investigated the antihyperuricemic activity and mechanism of quinoa bran saponins (QBSs) in hyperuricemic mouse and cell models. The QBS4 fraction, with the highest saponin content, was used. Fourier-transform infrared, high-performance liquid chromatography, and ultrahigh-performance liquid chromatography-mass spectrometry identified 11 individual saponins in QBS4, of which the main components were hederagenin and oleanolic acid. The QBS4 effects on hyperuricemic mice (induced by adenine and potassium oxonate) were then studied. QBS4 reduced the levels of uric acid (UA), serum urea nitrogen, creatinine, and lipids in mice with hyperuricemia (HUA) and decreased renal inflammation and renal damage. Molecular analysis revealed that QBS4 may alleviate HUA by regulating the expression of key genes involved in the transport of UA and by inhibiting the activation of the PI3K/AKT/NFκB inflammatory signaling pathway. In conclusion, QBS4 has promise for using as a natural dietary supplement to treat and prevent HUA.


Assuntos
Injúria Renal Aguda , Chenopodium quinoa , Hiperuricemia , Chenopodium quinoa/química , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Saponinas/uso terapêutico , Hiperuricemia/tratamento farmacológico , Hiperuricemia/metabolismo , Transdução de Sinais , Fosfatidilinositol 3-Quinases/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Masculino , Animais , Camundongos
12.
Hum Brain Mapp ; 44(4): 1603-1616, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36515634

RESUMO

The comprehension of spoken language is one of the most essential language functions in humans. However, the neurological underpinnings of auditory comprehension remain under debate. Here we used multi-modal neuroimaging analyses on a group of patients with low-grade gliomas to localize cortical regions and white matter tracts responsible for auditory language comprehension. Region-of-interests and voxel-level whole-brain analyses showed that cortical areas in the posterior temporal lobe are crucial for language comprehension. The fiber integrity assessed with diffusion tensor imaging of the arcuate fasciculus and the inferior longitudinal fasciculus was strongly correlated with both auditory comprehension and the grey matter volume of the inferior temporal and middle temporal gyri. Together, our findings provide direct evidence for an integrated network of auditory comprehension whereby the superior temporal gyrus and sulcus, the posterior parts of the middle and inferior temporal gyri serve as auditory comprehension cortex, and the arcuate fasciculus and the inferior longitudinal fasciculus subserve as crucial structural connectivity. These findings provide critical evidence on the neural underpinnings of language comprehension.


Assuntos
Neoplasias Encefálicas , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Compreensão , Imagem de Tensor de Difusão/métodos , Mapeamento Encefálico/métodos , Vias Neurais/diagnóstico por imagem , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico por imagem
13.
Pest Manag Sci ; 79(1): 402-414, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36175385

RESUMO

BACKGROUND: Currently, the variable-rate application (VA) of agrochemicals on fruit trees is based on canopy volume and biomass. The canopy volume has a significant relationship with disease resistance and degree of disease incidence. Therefore, this study proposes a VA method that uses deep convolutional neural networks for real-time recognition of disease spots on pear trees. Furthermore, it specifies the limitations and application scenarios of the disease spot recognition. Field performance tests were conducted to verify the performance of the proposed VA system. RESULTS: The results showed a mean average precision, precision, and recall of 87.42%, 83.76%, and 87.23%, respectively. The spot recognition rate was 81.3% when the canopy sampling distance, spot diameter, and canopy porosity were 1.2 m, 4-8 mm, and 55.76%, respectively. The results indicate that the proposed VA system saved 51.9% spray volume compared to conventional methods while ensuring quality. CONCLUSION: Compared to the traditional constant rate model, the proposed VA technology based on real-time disease spot identification can reduce spraying in nondiseased areas, thereby abandoning the previous saturation application practice and significantly reducing pesticide use. © 2022 Society of Chemical Industry.

14.
Foods ; 13(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38201084

RESUMO

The global production of quinoa has been increasing in recent years. In plant-based foods, ultrasound stress has received increasing attention, owing to its ability to enhance the production of primary and secondary metabolites. We studied the effects of ultrasonic stress at the pre-germination stage on the γ-aminobutyric acid (GABA) accumulation and characteristics of nutrition and function in quinoa. The results showed that ultrasonic conditions of 100 W for 4 min promoted an increase in GABA content by 9.15-fold, to 162.47 ± 6.69 mg/100 g·DW, compared to that of untreated quinoa, through promoting a 10.2% and 71.9% increase in the water absorption and glutamate decarboxylase activity of quinoa, respectively. Meanwhile, compared to untreated quinoa, ultrasonic stress at the pre-germination stage enhanced the total phenolic, total flavonoid, and total saponin contents of quinoa by 10.2%, 33.6%, and 90.7%, to 3.29 mg GA/g·DW, 104.0 mg RE/100 g·DW, and 7.13 mg/g, respectively, without decreasing its basic nutritional quality. Ultrasonic stress caused fissures on the surface of quinoa starch particles. Additionally, germination under ultrasonic stress increased the n3 polyunsaturated fatty acids by 14.4%. Furthermore, ultrasonic stress at the pre-germination stage promoted the scavenging of 2,2-diphenyl1-picrylhydrazyl radicals and inhibitions of α-amylase, α-glucosidase, and pancreatic lipase by 14.4%, 14.9%, 24.6%, and 20.0% in vitro, compared to untreated quinoa. The results indicated that the quinoa sprouted via ultrasonic stress could represent a promising method through which to develop nutritionally balanced whole grains rich in GABA, with hypoglycemic and hypolipidemic activities, which could provide theoretical support for the development of functional whole-grain foods based on quinoa.

15.
Int J Med Sci ; 19(7): 1155-1162, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35919816

RESUMO

Ischemic stroke is one of the leading causes of death and disability. Ischemia triggers a cascade of events leading to cell death and cerebral infarction. Mesenchymal stem cell (MSC) therapy is a promising treatment modality to promote the development of nerve and blood vessels and improve nerve function. However, MSCs have a limited therapeutic effect in the harsh microenvironment of ischemic brain tissue. Modified MSC therapy shows better therapeutic effect under different pathological conditions, and is expected to be translated into clinical practice. In this article, we review the latest advances in the development of modified MSCs for the treatment of cerebral ischemia. In particular, we summarize the targets involved in migration, homing, antioxidant stress, anti-inflammatory, nerve and vascular regeneration, providing new ideas for clinical transformation.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Acidente Vascular Cerebral , Animais , Isquemia Encefálica/terapia , Infarto Cerebral , Modelos Animais de Doenças , Humanos
16.
Stroke Vasc Neurol ; 7(4): 337-344, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35387894

RESUMO

BACKGROUND: Surgical treatment of posterior inferior cerebellar artery (PICA) aneurysms is challenging because many are nonsaccular and atherosclerotic. We report our tailored approach to PICA aneurysms, which is based on angioarchitecture supplemented by high-resolution vessel wall MRI (HR-VW MRI) findings. METHODS: From March 2010 to September 2020, 27 patients with 29 PICA aneurysms underwent surgical treatment in our institution. Since October 2016, HR-VW MRI has been used for aneurysmal wall assessment. Clinical characteristics, radiological data and surgical outcomes were analysed. RESULTS: Nineteen proximal PICA aneurysms (vertebral artery (VA), P1, P2 and P3) were treated using the far-lateral approach. Ten distal PICA aneurysms (P4, P5) were treated using the suboccipital midline approach. Direct clipping or clip reconstruction was achieved in 19 aneurysms. Ten were trapped in conjunction with extracranial-intracranial or intracranial-intracranial bypass, including three occipital artery-PICA reimplantations, three PICA-VA reimplantations, two PICA-PICA side-to-side anastomoses, one PICA-PICA reimplantation and one PICA-PICA reanastomosis. All aneurysms were eventually completely obliterated and all bypasses remained patent. At the last follow-up, 26 patients (96.2%) achieved a good outcome (modified Rankin Scale score <3). Eight patients underwent HR-VW MRI. Among these, the six aneurysms with focal wall enhancement required bypass and the two with negative enhancement were successfully clipped. CONCLUSION: PICA aneurysms have a higher frequency of complex features such as large or giant size and fusiform or dissecting morphology. Favourable outcomes were achieved with individualised microsurgical strategies based on angioarchitecture. HR-VW MRI may be used as a promising technique to predict aneurysmal atherosclerosis.


Assuntos
Revascularização Cerebral , Aneurisma Intracraniano , Cerebelo/irrigação sanguínea , Cerebelo/cirurgia , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Imageamento por Ressonância Magnética , Artéria Vertebral
17.
Sensors (Basel) ; 21(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34695971

RESUMO

Medium and small-scale high-clearance sprayers are widely applied in medium and small-scale farms. Owing to power and load limitations, it is difficult to manage the complex system for suppressing spray boom vibration. This study was conducted to design a spray boom-air suspension system suitable for medium and small-size high-clearance sprayers by combining spray boom vibration suppression and the characteristics of air spring charging/discharging. Thus, this study aims to address the non-homogeneous distribution of spray triggered by the spray boom vibrations in medium and small high-clearance sprayers. The effects of different elastic elements on the vibration suppression effect of the spray boom were compared. According to the bench test, the dynamic response results of the spray boom under transient and sinusoidal excitations indicate that air spring is more conducive to vibration suppression than coil spring. The results obtained from the field experiments indicate that under the low solid soil condition, the spray boom air suspension should match a small additional air chamber with a volume of approximately 0.6 L, and the damping coefficient of the damper should be approximately 1792 N·s/m. In the case of the high firm soil, the spray boom air suspension should match a large additional air chamber with a volume of approximately 3.6 L, while the damping coefficient of the damper should be set to approximately 1316 N·s/m. The soil with low moisture content and high firmness are unfavorable to the vibration suppression of the spray boom. This study provides a reference for enhancing the vibration suppression of the spray boom-air suspension and improving the spray uniformity of the sprayer.


Assuntos
Agricultura , Vibração , Solo , Suspensões
18.
Int J Mol Sci ; 22(13)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34281233

RESUMO

Osteosarcoma is a common malignant bone tumor in clinical orthopedics. Iron chelators have inhibitory effects on many cancers, but their effects and mechanisms in osteosarcoma are still uncertain. Our in vitro results show that deferoxamine (DFO) and deferasirox (DFX), two iron chelators, significantly inhibited the proliferation of osteosarcoma cells (MG-63, MNNG/HOS and K7M2). The viability of osteosarcoma cells was decreased by DFO and DFX in a concentration-dependent manner. DFO and DFX generated reactive oxygen species (ROS), altered iron metabolism and triggered apoptosis in osteosarcoma cells. Iron chelator-induced apoptosis was due to the activation of the MAPK signaling pathway, with increased phosphorylation levels of JNK, p38 and ERK, and ROS generation; in this process, the expression of C-caspase-3 and C-PARP increased. In an orthotopic osteosarcoma transplantation model, iron chelators (20 mg/kg every day, Ip, for 14 days) significantly inhibited the growth of the tumor. Immunohistochemical analysis showed that iron metabolism was altered, apoptosis was promoted, and malignant proliferation was reduced with iron chelators in the tumor tissues. In conclusion, we observed that iron chelators induced apoptosis in osteosarcoma by activating the ROS-related MAPK signaling pathway. Because iron is crucial for cell proliferation, iron chelators may provide a novel therapeutic strategy for osteosarcoma.


Assuntos
Deferasirox/uso terapêutico , Desferroxamina/uso terapêutico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Osteossarcoma/tratamento farmacológico , Sideróforos/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Deferasirox/farmacologia , Desferroxamina/farmacologia , Humanos , Ferro/metabolismo , Camundongos , Osteossarcoma/metabolismo , Sideróforos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Bioelectromagnetics ; 42(5): 371-383, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34082485

RESUMO

Static magnetic field (SMF) can alter cell fate decisions in many ways. However, the effects of SMF on cancer stem cells (CSCs) are little-known. In this particular study, we evaluate the biological effect of moderate-intensity SMF on osteosarcoma stem cells (OSCs) and try to clarify the underlying mechanisms of action. First, we demonstrated that prolonged exposure to SMF induced the proliferation and tumorsphere formation in K7M2 and MG63 OSCs. Moreover, SMF promoted the release of ferrous iron (Fe2+ ) and provoked reactive oxygen species (ROS) in OSCs. Interestingly, SMF evidently triggered the autophagic degradation of ferritin, which is characterized by the activation of microtubule-associated protein 1 light chain 3 (LC3) and nuclear receptor co-activator 4 (NCOA4), and downregulation of ferritin heavy chain 1 (FTH1) in OSCs. Particularly, the colony-forming ability of K7M2 OSCs promoted by SMF was obviously abolished by using a small interfering RNA (siRNA) against NCOA4. Finally, treatment of the tumor-bearing mice with SMF did not affect the tumor volume or tumor mass, nor pulmonary metastasis of K7M2 OSCs, but the SMF-treated K7M2 OSCs caused a preference of pulmonary metastasis in a mouse model, which suggested that SMF might induce the metastatic characteristic of OSCs. Consequently, this paper demonstrates for the first time that the cumulative SMF exposure promoted the self-renewal ability of OSCs via autophagic degradation of ferritin, implying that ferritinophagy may be a potential molecular target for cancer. © 2021 Bioelectromagnetics Society.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Animais , Ferritinas , Campos Magnéticos , Camundongos , Células-Tronco
20.
Appl Microbiol Biotechnol ; 105(9): 3759-3770, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33900424

RESUMO

Candida albicans (C. albicans) is a fungal pathogen that is difficult to cure clinically due to lack of effective antifungal agents with low toxicity. In this study, iturin, a cyclic peptide having wide antifungal spectrum, was used to synthesize nanosilver particles (AgNPs), and a complex of iturin-AgNPs was formed. The antifungal activity of iturin-AgNPs against C. albicans and its mechanisms were tested in vitro. Iturin-AgNPs were also loaded in chitosan (CS) composite dressing and applied to skin wound healing in mice. As results, iturin-AgNPs showed excellent antifungal activity with the minimum inhibitory concentrations (MIC) of 1.25, 2.5, and 5 µg/mL at C. albicans concentrations of 1×105, 1×106, and 1×107 CFU/mL, respectively. The MIC value still kept at 2.5 µg/mL against C. albicans (105 CFU/mL) after 15 regeneration, showing less induction of drug resistance to the pathogenic fungus. The antifungal mechanisms of iturin-AgNPs against C. albicans were identified as the increase of membrane permeability, damage of cell membrane integrity, and leakage of cellular protein and nucleic acids. No toxicity was found for iturin-AgNPs to HaCaT cells at concentrations of lower than 10 µg/mL. In wound healing application, iturin-AgNP CS composite dressing significantly accelerated the healing of C. albicans infected skin wounds at the early 10 days. In conclusion, iturin-AgNPs were developed as an efficient antifungal agent against C. albicans in vitro and in vivo and showed potential application in wound healing promotion.


Assuntos
Candida albicans , Nanopartículas Metálicas , Animais , Antifúngicos/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Prata/farmacologia
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