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1.
Mol Cell Endocrinol ; : 110742, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-32006608

RESUMO

Epidemiological evidence suggests that the etiology and pathogenesis of rheumatoid arthritis (RA) are closely associated with estrogen metabolism and deficiency. Estrogen protects against articular damage. Estradiol replacement therapy ameliorates local inflammation and knee joint swelling in ovariectomized models of RA. The mechanistic basis for the protective role of 17ß-estradiol (17ß-E2) is poorly understood. Acid-sensing ion channel 1a (ASIC1a), a sodium-permeable channel, plays a pivotal role in acid-induced articular chondrocyte injury. The aims of this study were to evaluate the role of 17ß-E2 in acid-induced chondrocyte injury and to determine the effect of 17ß-E2 on the level and activity of ASIC1a protein. Results showed that pretreatment with 17ß-E2 attenuated acid-induced damage, suppressed apoptosis, and restored mitochondrial function. Further, 17ß-E2 was shown to reduce protein levels of ASIC1a through the autophagy-lysosomal pathway, to protect chondrocytes from acid-induced apoptosis, and to induce ASIC1a protein degradation through the ERα receptor. Taken together, these results show that the use of 17ß-E2 may be a novel strategy for the treatment of RA by reducing cartilage destruction through down-regulation of ASIC1a protein levels.

3.
Biochem Biophys Res Commun ; 504(4): 843-850, 2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30219231

RESUMO

Necroptosis, a necrotic cell death pathway regulated by receptor interacting protein (RIP) 1 and 3, plays a key role in pathophysiological processes, including rheumatoid arthritis (RA). However, whether necroptosis is involved in RA articular cartilage damage processes remain unclear. The aim of present study was to investigate the dynamic changes in arthritic chondrocyte necroptosis and the effect of RIP1 inhibitor necrostatin-1 (Nec-1) and acid-sensing ion channels (ASICs) inhibitor amiloride on arthritic cartilage injury and acid-induced chondrocyte necroptosis. Our results demonstrated that the expression of RIP1, RIP3 and mixed lineage kinase domain-like protein phosphorylation (p-MLKL) were increased in adjuvant arthritis (AA) rat articular cartilage in vivo and acid-induced chondrocytes in vitro. High co-expression of ASIC1a and RIP1 showed in AA rat articular cartilage. Moreover, Nec-1 and amiloride could reduce articular cartilage damage and necroinflammation in AA rats. In addition, acid-induced increase in necroptosis markers RIP1/RIP3 were inhibited by Nec-1, ASIC1a-specific blocker psalmotoxin-1 (PcTx-1) or ASIC1a-short hairpin RNA respectively, which revealed that necroptosis is triggered in acid-induced chondrocytes and mediated by ASIC1a. These findings indicated that blocking ASIC1a-mediated chondrocyte necroptosis may provide potential therapeutic strategies for RA treatment.


Assuntos
Canais Iônicos Sensíveis a Ácido/metabolismo , Artrite Experimental/tratamento farmacológico , Condrócitos/efeitos dos fármacos , Imidazóis/farmacologia , Indóis/farmacologia , Canais Iônicos Sensíveis a Ácido/genética , Amilorida/farmacologia , Animais , Artrite Experimental/etiologia , Artrite Experimental/patologia , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Condrócitos/patologia , Masculino , Necrose/tratamento farmacológico , Peptídeos/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Ratos Sprague-Dawley , Venenos de Aranha/farmacologia
4.
Biochem Biophys Res Commun ; 503(3): 2033-2039, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30078681

RESUMO

4-Amino-2-Trifluoromethyl-Phenyl Retinate (ATPR), an all-trans retinoic acid (ATRA) derivative, possesses the ability to relief several carcinoma. Here, we explored the potential molecular mechanism of eukaryotic translation initiation factor 6 (eIF6) in ATPR-induced leukemia cell differentiation. Our research showed that ATPR could inhibit cell proliferation and promote cell differentiation in several leukemia cell lines. Besides, ATPR remarkably reduced the expression of eIF6 in vitro. Interestingly, the reduction of eIF6 contributed to restraining proliferation of K562 cells by inhibiting CyclinD1, C-myc and blocking cell cycle, as well as promoting differentiation of K562 cells by increasing the expression of C/EBPε, cell surface antigen CD11b and inducing renal-shrinkage of nuclear. Furthermore, the over-expression of eIF6 restrained the effects of ATPR on cell proliferation and maturation in K562 cells. In Addition, Notch1/CBF-1 signal activated by Chrysin could increase expression of eIF6 and restrain the differentiation in ATPR-induced K562 cells. Taken together, all above results indicated that ATPR induced differentiation of leukemia cells by decreasing eIF6 through Notch1/CBF-1 signal, which might exert an innovative treatment for leukemia.


Assuntos
Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Fatores de Iniciação em Eucariotos/deficiência , Leucemia/metabolismo , Leucemia/patologia , Retinoides/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fatores de Iniciação em Eucariotos/genética , Fatores de Iniciação em Eucariotos/metabolismo , Humanos , Células K562 , Leucemia/genética , Retinoides/química , Relação Estrutura-Atividade , Células THP-1 , Células Tumorais Cultivadas
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(5): 1234-9, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25095413

RESUMO

Cationic Polyacrylamide P(AM-DAC-BA) was synthesized by UV initiation, with acrylamide (AM), acryloyloxyethyl trimethyl ammonium chloride (DAC), butyl acrylate (BA) as the monomers. P(AM-DAC-BA). UV spectroscopy and infrared spectroscopy were employed to study the structural characteristics. Attributions of typical infrared vibrational frequencies in AM/DAC/BA/P(AM-DAC-BA) were analysed. By comparing with infrared spectroscopy of the monomers, symmetrical characteristic of P(AM-DAC-BA) increasesd, and the infrared spectroscopy of polymerization product was simpler. The intrinsic viscosity increased with the increase in light intensity, BA content, photoinitiator concentration and illumination time. The groups of -CONH2, -COOCH2(C=O), -COOCH2--(C-O-C), -CH2--N(CH3 )3 group in AM, DAC, BA were selected as characteristic absorption peaks for studying. With the increase in light intensity and BA content, the characteristic peak areas increased. With the increase in photoinitiator concentration, the characteristic peak areas decreased. The characteristic peak areas decreased firstly and then increased with increasing the illumination time. But the corresponding characteristic IR absorption peaks of P(AM-DAC-BA) were similar, and the positions of characteristic peaks were basically the same.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(2): 334-8, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22512163

RESUMO

Cationic degree has been investigated as an important factor in polyacrylamide materials. Diallyl dimethyl ammonium chloride and acrylamide (PDA) was grafted by free radical polymerisation of acrylamide monomer (AM) onto the cationic monomer dimethyl diallyl ammonium chloride (DMDAAC). In the present study, near infrared reflectance spectroscopy (NIRS) was used as a rapid and accurate method to determine the cationic degree in the PDA. In this experiment, the near infrared spectra of 37 PDA samples that were self-prepared in the laboratory from 900.00 to 1 700.00 were collected. The characteristic peaks and the entire spectrum segment as the input layer neurons in radical basis function (RBF) were investigated for establishing the mathematical conversion NIRS calibration mode. For reduction of the NIR spectrum noise, the wavelet analysis was used as pretreatment process. The measured value was determined by using precipitation titration and a comparison between the simulated value and measured value was made. It was found that the external validation determination coefficient was more than 0.9, and the simulation value is in good agreement with the measured value. The statistics analysis showed that there was no significant difference between simulated value and measured value. Therefore, the calibration model (RBF neural network) established in this paper exhibited a remarkable feasibility for predicting the cationic degree of PDA based on the near infrared spectroscopy.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(11): 2944-7, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22242491

RESUMO

In the present study, near infrared reflectance spectroscopy(NIRS) was used as a rapid and accurate method to determine the residual of acrylamide monomer in the product of diallyl dimethyl ammonium chloride and acrylamide. In this experiment 38 products were used which were self-prepared in the laboratory, then near infrared spectra of the product were scanned, seven bands were selected, the characteristic peaks of each band were used as the independent variables, and the absorption peak was used as the dependent variable, using partial least squares (PLS) method to establish the mathematical conversion near infrared reflectance spectroscopy (NIRS) calibration model. In the analysis of the spectrum, using wavelet analysis as the method of reducing the noise of spectrum, and with comparison of the simulated value and measured value, the measured value was determined by using UV spectrum, the external validation determination coefficient was found to be 0.99, and the distribution trend forecast was good. Statistics showed that there was no significant difference between simulated value and measured value. The results show that using the calibration model established by the data of near infrared spectroscopy to predict the residual AM monomer in PDA is of high feasibility.

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