Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
EMBO J ; 39(10): e103111, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32187724

RESUMO

The homeostatic link between oxidative stress and autophagy plays an important role in cellular responses to a wide variety of physiological and pathological conditions. However, the regulatory pathway and outcomes remain incompletely understood. Here, we show that reactive oxygen species (ROS) function as signaling molecules that regulate autophagy through ataxia-telangiectasia mutated (ATM) and cell cycle checkpoint kinase 2 (CHK2), a DNA damage response (DDR) pathway activated during metabolic and hypoxic stress. We report that CHK2 binds to and phosphorylates Beclin 1 at Ser90/Ser93, thereby impairing Beclin 1-Bcl-2 autophagy-regulatory complex formation in a ROS-dependent fashion. We further demonstrate that CHK2-mediated autophagy has an unexpected role in reducing ROS levels via the removal of damaged mitochondria, which is required for cell survival under stress conditions. Finally, CHK2-/- mice display aggravated infarct phenotypes and reduced Beclin 1 p-Ser90/Ser93 in a cerebral stroke model, suggesting an in vivo role of CHK2-induced autophagy in cell survival. Taken together, these results indicate that the ROS-ATM-CHK2-Beclin 1-autophagy axis serves as a physiological adaptation pathway that protects cells exposed to pathological conditions from stress-induced tissue damage.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteína Beclina-1/metabolismo , Quinase do Ponto de Checagem 2/metabolismo , AVC Isquêmico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Autofagia , Linhagem Celular , Modelos Animais de Doenças , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Camundongos , Estresse Oxidativo , Fosforilação
2.
Zhonghua Nan Ke Xue ; 22(4): 315-9, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-30088403

RESUMO

Objective: To investigate the understanding of and attitude towards sperm donation among males of the right age in Shandong Province a provide some reference for improving the propaganda for sperm donation and the recruitment of sperm donors. Methods: We conducted a questionnaire survey among the male students and other men of the right age for sperm donation in the three cities of Shandong Province, Jinan, Qingdao and Yantai, with the questionnaires distributed randomly and filled in anonymously on the spot. Then we performed statistical analysis on the 2 000 valid copies collected. Results: Among the 2 000 males, only 227(11. 35%) accepted sperm donation,997(49. 85%) knew that sperm donation was harmless to health, and merely 9. 95% had donated or considered donating sperm. The misgivings about sperm donation mainly included possible ethical problems, personal privacy, the complicated procedure, and high requirements. Conclusion: Most males of the right age have misgivings about sperm donation. The propaganda for sperm donation in Shandong human sperm banks are relatively monotonous and needs to be improved.


Assuntos
Atitude , Bancos de Esperma , Obtenção de Tecidos e Órgãos , Humanos , Masculino , Espermatozoides , Estudantes , Inquéritos e Questionários
3.
J Biomed Nanotechnol ; 18(4): 1052-1063, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35854453

RESUMO

Glioblastoma, the most common tumor in the brain, has witnessed very little clinical progress over the last decades. Exploring and discovering new therapeutic strategies for glioblastoma has become a critical problem. Harmine (HM), belonging to the beta-carboline alkaloid, is a natural product and isolated from the seeds of Peganum harmala L., which own notable antitumor activity in vitro. However, the poor water solubility and less selectivity of HM severely limit its clinical use. For enhancing its selective ability to tumor cells, we fabricated a kind of protein nanoparticles (BSA-HM NPs), composed of the modified bovine serum albumin (BSA) and HM. It was substantiated through in vitro and in vivo experiment that BSA-HM NPs could predominantly accumulate in tumor tissues and exhibited remarkably enhanced antitumor efficacy. This study provides a promising strategy to improve the bioavailability and avoid side effects of HM as antitumor agents by choosing BSA as carriers.


Assuntos
Antineoplásicos , Glioblastoma , Nanopartículas , Antineoplásicos/farmacologia , Glioblastoma/tratamento farmacológico , Harmina/farmacologia , Humanos , Soroalbumina Bovina
4.
Fitoterapia ; 162: 105290, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36064152

RESUMO

Excess levels of chemical hepatotoxicants (alcohol, aflatoxin B1), oxidative drugs (acetaminophen) and some cytokines (ET-1, TGF-ß1) can induce chronic or acute liver injury. After these, the severe hepatic disease, especially the liver fibrosis (LF) occurs without taking measures, which brings threat to human health. The dibenzocyclooctadiene lignans of S. chinensis (SCDLs) were found to act as the hepatoprotective components via blocking endothelin B receptor (ETBR). While study on its anti-LF mechanisms especially for its refined compound of schisantherin D (SC-D) is still a lack. So this study aims to investigate the anti-fibrosis effect of SC-D with in vitro and in vivo assays. Bioinformatics analysis revealed the close relations of ETBR to Smad2, Smad3, Nrf2, etc. in LF-related signaling pathways (such as TGF-ß/Smad and Nrf2/ARE). Histopathological staining on livers showed the recovery trend in SC-D treated LF mice. SC-D also modulated expressions of ETBR and fibrosis or anti-oxidative related proteins (such as TIMP1, p-Smad2/3, Nrf2, Smad7, etc.) in LF mice livers. Serum levels of TNF-α, COLI, ALT, AST and LDH in SC-D treated mice were also downregulated compared with LF mice, and upregulated expression of GSH. In vitro studies, SC-D also modulated expressions of LF-related proteins to the normal tendency in LX-2 cell, while weakened its anti- LX-2 proliferation effect by transfections of si-Smad7 or si-Nrf2. Accordingly the anti-LF approach of SC-D showed relations with modulating ETBR linked fibrosis and anti-oxidative related signaling. Also, Smad7 and Nrf2 might be the key factors for SC-D mediated anti-LF effect.


Assuntos
Lignanas , Schisandra , Acetaminofen , Aflatoxina B1 , Animais , Dioxóis , Humanos , Lignanas/farmacologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Camundongos , Estrutura Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Receptor de Endotelina B/uso terapêutico , Schisandra/química , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1 , Fator de Necrose Tumoral alfa
5.
Int Urol Nephrol ; 54(7): 1681-1691, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34783980

RESUMO

PURPOSE: To evaluate the effects of manganese superoxide dismutase (Mn-SOD) from thermophilic bacterium HB27 (name as Tt-SOD) on chemical cystitis. METHODS: Control and experimental rats were infused by intravesical saline or hydrochloric acid (HCl) on the first day of the experiments. Saline, sodium hyaluronate (SH) or Tt-SOD were infused intravesically once a day for three consequent days. On the fifth day, the rats were weighted and sacrificed following a pain threshold test. The bladder was harvested for histological and biochemical analyses. RESULTS: Tt-SOD could reduce the bladder index, infiltration of inflammatory cells in tissues, serum inflammatory factors and SOD levels, mRNA expression of inflammatory factors in tissues, and increase perineal mechanical pain threshold and serum MDA and ROS levels in HCl-induced chemical cystitis. Furthermore, Tt-SOD alleviated inflammation and oxidative stress by the negative regulation of the NF-κB p65 and p38 MAPK signaling pathway. CONCLUSIONS: Intravesical instillation of Tt-SOD provides protective effects against HCl-induced cystitis.


Assuntos
Proteínas de Bactérias , Cistite , Superóxido Dismutase , Animais , Proteínas de Bactérias/uso terapêutico , Cistite/induzido quimicamente , Cistite/terapia , Ácido Clorídrico/efeitos adversos , Inflamação/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/uso terapêutico , Bexiga Urinária/patologia
6.
Cancer Manag Res ; 12: 10669-10678, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33149674

RESUMO

PURPOSE: In order to investigate the role of miR-15b-5b in the progression of prostate cancer. METHODS: We employed RT-qPCR assay to analyze the transcriptional level of miR-15b-5b in cell lines including PC-3, prostate cancer tissues as well as normal prostate tissues. The protein level of large tumor suppressor factor 2 (LATS2) was detected by Western blot in similar specimens. Bioinformatic analysis was used to predict the targets of miR-15b-5p, and dual-luciferase assay was performed to confirm the relationship of miR-15b-5p with LATS2. Cell proliferation assay and colony formation assay were used to assess the effects of miR-15b-5b on the proliferation of PC-3 cells. Multivariate analysis was performed to identify factors associated with overall survival using the Cox proportional hazards model. RESULTS: MiR-15b-5b was up-regulated in prostate cancer tissues as well as cell lines, and increased expression of miR-15b-5b was highly correlated with the poor prognosis of patients with prostate cancer. Ectopic expression of miR-15b-5b promoted the proliferation of PC-3 cells. Reciprocally, silence of miR-15b-5b elicited opposite effects on cell proliferation. Mechanistically, we identified LATS2 as the target of miR-15b-5b, which in turn limited LATS2 expression in PC-3 cells. Furthermore, the stimulatory effects of miR-15b-5b on cell proliferation can be attenuated by overexpression of LATS2. Conversely, inhibition of LATS2 promoted the proliferation of PC-3 cells induced by miR-15b-5b. Our data thus demonstrate that dysregulation of miR-15b-5b exacerbates prostate cancer progression via suppression of LATS2. CONCLUSION: The identification of the oncogenic role of miR-15b-5b in prostate cancer thus proposes that miR-15b-5p might be a new therapeutic target for the treatment of prostate cancer.

7.
Medicine (Baltimore) ; 99(50): e23414, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33327266

RESUMO

Our study aimed to investigate the effect of intravenous thrombolysis with alteplase and edaravone on cerebral hemodynamics and T lymphocyte level in patients harboring acute cerebral infarction.There involved a total of 118 patients with acute cerebral infarction from November 2017 to May 2019 in our hospital were randomly divided into 2 groups: the observation group (59 patients were treated with intravenous thrombolysis with alteplase combined with edaravone) and the control group (59 patients were treated with intravenous thrombolysis of alteplase). The clinical effect, neurological function, cerebral hemodynamic index, T lymphocyte level, oxygen free radical scavenging level and oxidative stress index of the 2 groups were observed and compared.Before the treatment, there were no significant differences in neurological function, cerebral hemodynamic indexes, T-lymphocyte level, oxygen free radical scavenging level and oxidative stress indexes between the 2 groups (P > .05). After the treatment, the neurological function, cerebral hemodynamic indexes, T-lymphocyte level, oxygen free radical scavenging level and oxidative stress indexes of the 2 groups were significantly improved. In addition, the observation group exerted greater beneficial effect in terms of the clinical effect, neurologic function, cerebral hemodynamic index, T lymphocyte level, oxygen free radical scavenging level and oxidative stress index than those of the control group (P < .05).The intravenous thrombolysis with alteplase and edaravone is effective in the treatment of acute cerebral infarction, which also provides better results in terms of improving the clinical efficacy and prognosis of patients and might be an alternative option for clinical practice.


Assuntos
Infarto Cerebral/tratamento farmacológico , Edaravone/administração & dosagem , Fibrinolíticos/administração & dosagem , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tecidual/administração & dosagem , Doença Aguda , Administração Intravenosa , Adulto , Idoso , Circulação Cerebrovascular/efeitos dos fármacos , Quimioterapia Combinada , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Linfócitos T/efeitos dos fármacos , Resultado do Tratamento
8.
Brain Behav ; 10(8): e01661, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32533644

RESUMO

PURPOSE: The present clinical study was conducted to investigate the effect of oxiracetam combined with ginkgo biloba extract in treating patients with acute intracerebral hemorrhage. METHODS: Ninety-eight patients with acute cerebral hemorrhage admitted to our hospital were divided into three groups. The differences of brain edema and cerebral hemorrhage were compared between the three groups after 1 and 2 weeks of treatment, and the recovery of neurological function, serum inflammatory factors, AQP-4, MMP-9, cognitive function, activities of daily living, and adverse reactions were compared between the three groups after 2 weeks of treatment. RESULTS: There was no significant difference among the three groups before treatment (p > .05). After treatment, the recovery of neurological function, serum inflammatory factors, AQP-4, MMP-9 levels, cognitive function, and activities of daily living were improved. Among them, the neurological function recovery, serum inflammatory factors, AQP-4, MMP-9 levels, cognitive function, and activities of daily living in the combined treatment group and the control group elicited greater results than those in the routine group. The results of the combined treatment group showed the most significant difference (p < .05). The concentration of IL-6 decreased from 135.98 ± 12.54 to 91.83 ± 7.69 pg/ml, AQP-4 from 227.55 µg/L ± 21.06 to 114.31 ± 9.22 µg/L, and MMP-9 from 172.39 ± 9.81 to 94.98 ± 5.01 ng/ml. In addition, the neurological function recovery, the levels of serum inflammatory factors, cognitive function, and activities of daily living in the combined treatment group were better than those in the control group (p < .05). The mean score of MRS in the combined treatment group decreased from 3.36 ± 0.98 at admission to 1.91 ± 0.38. CONCLUSION: Oxiracetam combined with Ginkgo biloba extract in the treatment of acute cerebral hemorrhage has a significant improvement effect.


Assuntos
Hemorragia Cerebral , Ginkgo biloba , Atividades Cotidianas , Adulto , Hemorragia Cerebral/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fitoterapia , Extratos Vegetais , Pirrolidinas
9.
Bioresour Technol ; 219: 710-715, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27560367

RESUMO

Synergistic combination of cellulase and xylanase has been performed on pre-treated substrates in many previous studies, while few on natural substrates. In this study, three unpretreated lignocellulosic substrates were studied, including corncob, corn stover, and rice straw. The results indicated that when the mixed cellulase and xylanase were applied, reducing sugar concentrations were calculated as 19.53, 15.56, and 17.35mg/ml, respectively, based on the 3,5 dinitrosalicylic acid (DNS) method. Compared to the treatment with only cellulose, the hydrolysis yields caused by mixed cellulase and xylanase were improved by 133%, 164%, and 545%, respectively. In addition, the conversion yield of corncob, corn stover, and rice straw by cellulase-xylanase co-treatment reached 43.9%, 48.5%, and 40.2%, respectively, based on HPLC analysis, which confirmed the synergistic effect of cellulase-xylanase that was much higher than either of the single enzyme treatment. The substrate morphology was also evaluated to explore the synergistic mechanism of cellulase-xylanase.


Assuntos
Celulase/química , Lignina/química , Oryza/química , Xilosidases/química , Zea mays/química , Biotecnologia/métodos , Carboidratos/química , Celulase/metabolismo , Celulose/química , Celulose/metabolismo , Hidrólise , Lignina/metabolismo , Microscopia Eletrônica de Varredura , Oryza/metabolismo , Brotos de Planta/química , Brotos de Planta/metabolismo , Xilosidases/metabolismo , Zea mays/metabolismo
10.
Bioengineered ; 7(3): 198-204, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27116398

RESUMO

Cellulose is an abundant natural polysaccharide that is universally distributed. It can be extracted from corncobs, which are inexpensive, easily accessible, renewable, and environmentally friendly. A common strategy for effectively utilizing cellulose is efficient heterogeneous expression of cellulase genes in Saccharomyces cerevisiae. However, the improvement of cellulose utilization is a relevant issue. Based on our previous findings, we constructed an integrated secretion expression vector, pHBM368-pgk, containing a constitutive promoter sequence. Three genetically modified S. cerevisiae strains containing heterologous ß-glucosidase, exoglucanase, and endoglucanase genes were constructed. The results of a 1-L bioreactor fermentation process revealed that the mixed recombinant S. cerevisiae could efficiently carry out simultaneous saccharification and fermentation (SSF) by using corncobs as the sole carbon source. The ethanol concentration reached 6.37 g/L after 96 hours of fermentation, which was about 3 times higher than that produced by genetically modified S. cerevisiae with the inducible promoter sequence. To investigate the microstructure characteristics of hydrolyzed corncobs during the fermentation process, corncob residues were detected by using a scanning electron microscope. This study provides a feasible method to improve the effect of SSF using corncobs as the sole carbon source.


Assuntos
Celulase/genética , Celulose 1,4-beta-Celobiosidase/genética , Saccharomyces cerevisiae/enzimologia , Transgenes , Zea mays/metabolismo , beta-Glucosidase/genética , Reatores Biológicos , Celulase/metabolismo , Celulose 1,4-beta-Celobiosidase/metabolismo , Etanol/metabolismo , Fermentação , Engenharia Genética , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Organismos Geneticamente Modificados , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/genética , Resíduos , Zea mays/ultraestrutura , beta-Glucosidase/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA