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1.
Cell Death Dis ; 14(11): 760, 2023 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-37993451

RESUMO

Lipid metabolism is the key to ferroptosis susceptibility. However, little is known about the underlying mechanisms in osteosarcoma cells. Functional restriction of bromodomain-containing protein 4 (BRD4) reduced the susceptibility to erastin-induced ferroptosis of osteosarcoma cells both in vitro and in vivo. Mechanically, BRD4 controls the splicing efficiency of the RNA precursor (pre-mACSL3) of ACSL3 (ACSL3) by recruiting serinerich/threonine protein kinase 2 (SRPK2) to assemble the splicing catalytic platform. Moreover, the AMP-binding domain of ACSL3 significantly influences arachidonic acid synthesis and thus determines the susceptibility to erastin-induced ferroptosis. Overall, we found a BRD4-mediated pre-mACSL3 splicing influences erastin-induced ferroptosis by affecting arachidonic acid synthesis in osteosarcoma cells. Data in this study fills some of the gap in understanding the post-transcriptional regulatory mechanisms of ACSL3 and provides new insights into the mechanisms of lipid metabolism regulation and its effect on susceptibility to ferroptosis in osteosarcoma cells.


Assuntos
Ferroptose , Osteossarcoma , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Ferroptose/genética , Precursores de RNA/genética , Precursores de RNA/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Quinases/metabolismo , Fatores de Transcrição/metabolismo , Ácido Araquidônico/farmacologia , Proteínas de Ligação a RNA , Osteossarcoma/genética , Fatores de Processamento de Serina-Arginina , Proteínas de Ciclo Celular/metabolismo
2.
J Bone Oncol ; 43: 100512, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38021073

RESUMO

Background: Acquired drug-resistance is the major risk factor for poor prognosis and short-term survival in patients with osteosarcoma (OS). Accumulating evidence has revealed that long noncoding RNAs (lncRNAs), including plasmacytoma variant translocation 1 (PVT1), play potential regulatory roles in the malignant development of OS. Considering the subcellular distribution of PVT1 as both nuclear and cytoplasmic lncRNA, a thorough exploration of its extensive mechanisms becomes essential. Methods: The GEO database was utilized for the acquisition of gene expression data, which was subsequently analyzed to fulfill the research objectives. The subcellular localization of PVT1 in OS cells was determined using fluorescence in situ hybridization (FISH) and quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, the sensitivity of OS cells to doxorubicin was comprehensively evaluated through measurements of cell viability, site-specific proliferation capacity, and the relative expression abundance of multidrug resistance-related proteins (MRPs). In order to investigate the differential response of OS cells with varying levels of PVT1 expression to doxorubicin, pulmonary metastasis mice models were established for in vivo studies. Molecular interactions were further examined using the dual-luciferase assay and RNA immunoprecipitation assay (RIP) to analyze the binding sites of miR-15a-5p and miR-15b-5p on PVT1 and G1/S-specific cyclinD1 (CCND1) mRNA. Furthermore, the chromatin immunoprecipitation (ChIP) and dual-luciferase assay were employed to assess the transcriptional activation of the proto-oncogene c-myc (MYC) on the CCND1 promoter and identify the corresponding binding sites. Results: In doxorubicin resistant OS cells, transcription levels of PVT1, MYC and CCND1 were significantly higher than those in original cells. In vivo experiments demonstrated that OS cells rich in PVT1 expression exhibited enhanced tumorigenicity and resistance to doxorubicin. In vitro experiments, it has been observed that overexpression of PVT1 in OS cells is accompanied by an upregulation of CCND1, thereby facilitating resistance to doxorubicin. Nonetheless, this PVT1-induced resistance can be effectively attenuated by the knockdown of CCND1. Mechanistically, PVT1 functions as a competitive endogenous RNA (ceRNA) that influences the expression of CCND1 by inhibiting the degradation function of miR-15a-5p and miR-15b-5p on CCND1 mRNA. Additionally, as a neighboring gene of MYC, PVT1 plays a role in maintaining MYC protein stability, which further enhances MYC-dependent CCND1 transcriptional activity. Conclusion: The resistance of OS cells to doxorubicin is facilitated by PVT1, which enhances the expression of CCND1 through a dual mechanism. This findings offer a novel perspective for comprehending the intricate regulatory mechanisms of long non-coding RNA in influencing the expression of coding genes.

3.
Hum Vaccin Immunother ; 16(3): 612-622, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-31567058

RESUMO

Adjuvanted-influenza vaccination is an efficient method for enhancing the immunogenicity of influenza split-virus vaccines for preventing influenza. However, the medical community's understanding of its performance in patients infected with HIV remains limited. To identify the advantages, we conducted a systematic review and meta-analysis with randomized controlled trials (RCTs) and cohort and case-control studies that have the immunogenicity and safety of influenza vaccines in patients infected with HIV as outcomes. We searched six different databases, and 1698 patients infected with HIV in 11 studies were included. Statistical analysis was performed to calculate the pooled standardized mean differences (SMD) or relative risk (RR) and 95% confidence interval (CI). Regarding immunogenicity, the pooled SMD of GMT (Geometric mean titer) for A/H1N1 was 0.61 (95%CI (0.40,0.82)), the pooled RR of seroconversion was 1.34 (95%CI (0.91,1.98)) for the H1N1 vaccine, 1.27(95%CI (0.64,2.52)) for the H3N2 vaccine, 1.19(95%CI (0.97,1.46)) for the B-type influenza vaccine. The pooled RR of seroprotection was 1.61 (95%CI (1.00,2.58)) for the H1N1 vaccine, 1.06 (95%CI(0.83,1.35)) for the H3N2 vaccine, and 1.13(95%CI(0.91,1.41)) for the B-type vaccine. Adjuvanted-influenza vaccination showed good general tolerability in patients infected with HIV, with the only significant increase being the rate of local pain at the injection site (RR = 2.03, 95%CI (1.06,3.86)). In conclusion, all studies evaluating injected adjuvanted influenza vaccination among patients infected with HIV showed acceptable levels of safety and immunogenicity.


Assuntos
Infecções por HIV , Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Adjuvantes Imunológicos , Anticorpos Antivirais , Infecções por HIV/complicações , Humanos , Vacinas contra Influenza/efeitos adversos , Influenza Humana/prevenção & controle , Vacinação
4.
Biomed Chromatogr ; 33(12): e4677, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31396971

RESUMO

An efficient ultra-performance liquid chromatography with diode-array detector method was established for simultaneous determination of six active components in Roukou Wuwei pills, namely gallic acid, piperine, costundide, dehydrocostus lactone, isoalantolactone and alantolactone. Chromatographic separation of six components was successfully achieved on an Waters BEH C18 column (50 × 2.1 mm, 1.7 µm) with a mobile phase composed of acetonitrile and water using a gradient elution. Gallic acid and piperine were detected at 270 nm and 343 nm, respectively; while costundide, dehydrocostus lactone, isoalantolactone and alantolactone were simultaneously measured at 225 nm. All six calibration curves showed good linearity (R2 ≥ 0.9994) between the peak area of each component and corresponding concentration. Relative standard deviations for inter- and intra-day precisions were <0.45 and 0.77%, respectively. The mean recovery rates ranged from 96.72 to 102.2% with relative standard deviations <2.07%. The developed method was validated in terms of linearity, precision and accuracy and then successfully applied for the quality control of commercial Roukou Wuwei samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Alcaloides/análise , Benzodioxóis/análise , Ácido Gálico/análise , Lactonas/análise , Limite de Detecção , Modelos Lineares , Piperidinas/análise , Alcamidas Poli-Insaturadas/análise , Reprodutibilidade dos Testes , Sesquiterpenos/análise
5.
Ying Yong Sheng Tai Xue Bao ; 29(10): 3302-3310, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30325155

RESUMO

In order to solve the problems of nutrient absorption and accumulation and provide theoretical basis for rational amount of calcium fertilization of peanut in saline land, the effects of calcium fertilizer application on absorption and accumulation of nutrients including nitrogen, phosphorus, potassium, calcium and magnesium in peanut under salt stress were examined. Using 'Huayu 25' as experimental material, four Ca levels [T1 (0), T2 (75), T3 (150) and T4 (225) kg·hm-2 CaO] were set under 0.3% salt stress in a pot experiment. The results showed that nutrient contents in peanut followed the order of nitrogen > potassium > calcium > phosphorus > magnesium. At the seedling stage, leaves were the absorption center of nitrogen and calcium, while stems were the center of phosphorus, potassium and magnesium, with nearly half of nutrient accumulation being distributed in the corresponding growth center. At mature stage, the absorption centers of nitrogen, phosphorus and potassium were transferred to pod. The accumulation of nitrogen and phosphorus in seed kernel reached to 72.3%-78.9%. The absorption centers of calcium and magnesium was still in the leaves and stems, with a distribution ratio of 49.8% and 32.6%, respectively. Salt stress significantly inhibited nutrient absorption and distribution in peanut, especially decreased the nitrogen accumulation in leaves and seed kernels. However, salt stress increased the magnesium accumulation in pod. Exogenous calcium application had significant positive effect on absorption and accumulation of nitrogen, phosphorus, calcium and magnesium in different organs of peanut under salt stress. It had significant adjustment on phosphorus accumulation in seed kernel, which was increased by more than 50%. Appropriate calcium content could significantly promote the peanut nutrient absorption and accumulation under salt stress and improve the distribution ratio of nitrogen, phosphorus, potassium in mature pods of peanut. According to the responses of nutrient absorption and distribution, the optimized application amount for calcium fertilizer under 0.3% salt stress was 150 kg·hm-2 CaO.


Assuntos
Arachis , Cálcio , Fertilizantes , Alimentos , Magnésio , Nitrogênio , Fósforo , Folhas de Planta , Potássio , Plântula
6.
Tumour Biol ; 35(7): 6867-77, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25051917

RESUMO

The meta-analysis was conducted to evaluate the correlations between common genetic polymorphisms in the IFN-γ gene and susceptibility to breast cancer. The following electronic databases were searched without language restrictions: MEDLINE (1966 ~ 2013), the Cochrane Library Database (issue 12, 2013), EMBASE (1980 ~ 2013), CINAHL (1982 ~ 2013), Web of Science (1945 ~ 2013), and the Chinese Biomedical Database (CBM) (1982 ~ 2013). Meta-analysis was performed with the use of the STATA statistical software. Odds ratios (OR) with their 95 % confidence intervals (95 % CIs) were calculated. Nine clinical case-control studies met all the inclusion criteria and were included in this meta-analysis. A total of 1,182 breast cancer patients and 1,525 healthy controls were involved in this meta-analysis. Three functional polymorphisms were assessed, including rs2069705 C>T, rs2430561 T>A, and CA repeats 2/X. Our meta-analysis results indicated that IFN-γ genetic polymorphisms might be significantly associated with an increased risk of breast cancer (allele model: OR = 1.37, 95 % CI = 1.03 ~ 1.83, P = 0.031; dominant model: OR = 1.55, 95 % CI = 1.01 ~ 2.37, P = 0.046; homozygous model: OR = 2.23, 95 % CI = 1.30 ~ 3.82, P = 0.004; respectively), especially the rs2430561 T>A polymorphism. Subgroup analysis based on ethnicity suggested that genetic polymorphisms in the IFN-γ gene were closely correlated with increased breast cancer risk among Asians (allele model: OR = 1.21, 95 % CI = 1.02 ~ 1.58, P = 0.017; dominant model: OR = 3.44, 95 % CI = 2.07 ~ 5.71, P < 0.001; recessive model: OR = 1.58, 95 % CI = 1.06 ~ 2.37, P = 0.025; homozygous model: OR = 1.83, 95 % CI = 1.19 ~ 2.80, P = 0.006; respectively), but not among Caucasians (all P > 0.05). Our meta-analysis supported the hypothesis that IFN-γ genetic polymorphisms may contribute to an increased risk of breast cancer, especially the rs2430561 T>A polymorphism among Asians.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Interferon gama/genética , Povo Asiático/genética , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Humanos , Fatores de Risco , População Branca/genética
7.
Zhong Yao Cai ; 32(11): 1746-8, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-20218300

RESUMO

OBJECTIVE: To study the optimal extraction process of chaihushugan powder by orthogonal design. METHODS: RP-HPLC method was developed for the determination of saikosaponin a, ferulic acid, hesperidin and paeoniflorin in chaihushugan powder. The contents of the components and the extraction yield were selected as assessment indices. Four factors were study by L9 (3(4)), including the alcohol concentration, amount of alcohol, duration of extraction and times of extraction. RESULTS: The optimal extracting condition was 80% alcohol consumed as 10 times of crude herb amount, and extracting two times for 90 min each time. CONCLUSION: This study supplies theoretical base for the development of chaihushugan powder formulation.


Assuntos
Bupleurum/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Ácido Oleanólico/análogos & derivados , Plantas Medicinais/química , Saponinas/análise , Tecnologia Farmacêutica/métodos , Benzoatos/análise , Benzoatos/isolamento & purificação , Hidrocarbonetos Aromáticos com Pontes/análise , Hidrocarbonetos Aromáticos com Pontes/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Cumáricos/análise , Ácidos Cumáricos/isolamento & purificação , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/química , Etanol/química , Glucosídeos/análise , Glucosídeos/isolamento & purificação , Hesperidina/análise , Hesperidina/isolamento & purificação , Temperatura Alta , Monoterpenos , Ácido Oleanólico/análise , Ácido Oleanólico/isolamento & purificação , Pós , Controle de Qualidade , Saponinas/isolamento & purificação , Solubilidade , Fatores de Tempo
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