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1.
Molecules ; 28(21)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37959807

RESUMO

Mycoplasma gallisepticum (MG) is recognized as a principal causative agent of avian chronic respiratory disease, inflicting substantial economic losses upon the poultry industry. However, the extensive use of conventional antibiotics has resulted in the emergence of drug resistance and various challenges in their clinical application. Consequently, there is an urgent need to identify effective therapeutic agents for the prevention and treatment of mycoplasma-induced respiratory disease in avian species. AMP-activated protein kinase (AMPK) holds significant importance as a regulator of cellular energy metabolism and possesses the capacity to exert an anti-inflammatory effect by virtue of its downstream protein, SIRT1. This pathway has shown promise in counteracting the inflammatory responses triggered by pathogenic infections, thus providing a novel target for studying infectious inflammation. Quercetin possesses anti-inflammatory activity and has garnered attention as a potential alternative to antibiotics. However, there exists a gap in knowledge concerning the impact of this activation on MG-induced inflammatory damage. To address this knowledge gap, we employed AlphaFold2 prediction, molecular docking, and kinetic simulation methods to perform a systematic analysis. As expected, we found that both quercetin and the AMPK activator AICAR activate the chicken AMPKγ1 subunit in a similar manner, which was further validated at the cellular level. Our project aims to unravel the underlying mechanisms of quercetin's action as an agonist of AMPK against the inflammatory damage induced by MG infection. Accordingly, we evaluated the effects of quercetin on the prevention and treatment of air sac injury, lung morphology, immunohistochemistry, AMPK/SIRT1/NF-κB pathway activity, and inflammatory factors in MG-infected chickens. The results confirmed that quercetin effectively inhibits the secretion of pro-inflammatory cytokines such as IL-1ß, TNF-α, and IL-6, leading to improved respiratory inflammation injury. Furthermore, quercetin was shown to enhance the levels of phosphorylated AMPK and SIRT1 while reducing the levels of phosphorylated P65 and pro-inflammatory factors. In conclusion, our study identifies the AMPK cascade signaling pathway as a novel cellular mediator responsible for quercetin's ability to counter MG-induced inflammatory damage. This finding highlights the potential significance of this pathway as an important target for anti-inflammatory drug research in the context of avian respiratory diseases.


Assuntos
Mycoplasma gallisepticum , NF-kappa B , Animais , NF-kappa B/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Quercetina/farmacologia , Quercetina/uso terapêutico , Mycoplasma gallisepticum/metabolismo , Sirtuína 1/metabolismo , Simulação de Acoplamento Molecular , Galinhas/metabolismo , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antibacterianos/uso terapêutico
2.
J Mater Sci Mater Med ; 32(5): 50, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33891193

RESUMO

Ti-xZr (x = 5, 15, 25, 35, 45% wt%) alloys with low elastic modulus and high mechanical strength were fabricated as a novel implant material. The biocompatibility of the Ti-xZr alloys was evaluated by osteoblast-like cell line (MG63) in terms of cytotoxicity, proliferation, adhesion, and osteogenic induction using CCK-8 and live/dead cell assays, electron microscopy, and real-time PCR. The Ti-xZr alloys were non-toxic and showed superior biomechanics compared to commercially pure titanium (cpTi). Ti-45Zr had the optimum strength/elastic modulus ratio and osteogenic activity, thus is a promising to used as dental implants.


Assuntos
Ligas/química , Materiais Biocompatíveis , Implantes Dentários , Teste de Materiais , Titânio/química , Zircônio/química , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Humanos , Osteoblastos , Osteogênese
3.
RSC Adv ; 11(26): 15785-15794, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35481200

RESUMO

Rebaudioside M (Reb M), as a natural and healthy Stevia sweetener, is produced by two glycosyltransferases that catalyze the serial glycosylation of Rebaudioside A (Reb A) and Rebaudioside D (Reb D) in cascade. Meanwhile, it is of great importance in developing an immobilization strategy to improve the reusability of glycosyltransferases in reducing the production cost of Reb M. Here, the recombinant glycosyltransferases, i.e., OsEUGT11 (UGT1) and SrUGT76G1 (UGT2), were expressed in Escherichia coli and covalently immobilized onto chitosan beads. UGT1 and UGT2 were individually immobilized and co-immobilized onto the beads that catalyze Reb A to Reb M in one-pot. The co-immobilized enzymes system exhibited ∼3.2-fold higher activity than that of the mixed immobilized enzymes system. A fairly high Reb A conversion rate (97.3%) and a high Reb M yield of 72.2% (4.82 ± 0.11 g L-1) were obtained with a feeding Reb A concentration of 5 g L-1. Eventually, after 4 and 8 reused cycles, the co-immobilized enzymes retained 72.5% and 53.1% of their original activity, respectively, showing a high stability to minimize the total cost of enzymes and suggesting that the co-immobilized UGTs is of potentially signficant value for the production of Reb M.

4.
Pharm Biol ; 57(1): 133-139, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30843752

RESUMO

CONTEXT: Calenduloside E (CE), one of the primary natural products found in Aralia elata (Miq.) Seem. (Araliaceae), possesses prominent anti-apoptotic potential. A previous study found that one of the anti-apoptotic CE targets is heat shock protein 90 AB1 (Hsp90AB1) by probe CE-P, while the other targets of CE still need to be identified with more efficient probes. OBJECTIVE: This study investigates CE analogue (CEA) as one clickable activity-based probe for use in exploring anti-apoptotic CE targets. MATERIALS AND METHODS: Pretreatment of HUVECs with CEA (1.25 µM) for 8 hr, followed by ox-LDL stimulation for 24 h. Flow cytometry analysis and JC-1 staining assays were performed The kinetic constant measurements were tested by the Biacore T200, CM5 Sensor Chip which was activated by using sulpho-NHS/EDC. Ligands were dissolved and injected with a concentration of 12.5, 6.25, 3.125, 1.56, 0.78 and 0 µM. RESULTS: CEA was confirmed to possess an anti-apoptotic effect. The probable targets of CE/CEA were calculated, and as one of the higher scores proteins (Fit values: 0.88/0.86), Hsp90 properly got our attention. Molecular modelling study showed that both CE and CEA could bind to Hsp90 with the similar interaction, and the docking scores (S value) were -7.61 and -7.33. SPR assay provided more evidence to prove that CEA can interact with Hsp90 with the KD value 11.7 µM. DISCUSSION AND CONCLUSIONS: Our results suggest that clickable probe CEA could alleviate ox-LDL induced apoptosis by a similar mechanism of anti-apoptotic CE, and afforded the possibility of identifying additional anti-apoptotic targets of CE.


Assuntos
Apoptose/efeitos dos fármacos , Química Click , Modelos Moleculares , Ácido Oleanólico/análogos & derivados , Saponinas/farmacologia , Relação Dose-Resposta a Droga , Citometria de Fluxo , Proteínas de Choque Térmico HSP90/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Lipoproteínas LDL/metabolismo , Simulação de Acoplamento Molecular , Ácido Oleanólico/administração & dosagem , Ácido Oleanólico/farmacologia , Saponinas/administração & dosagem
5.
ChemSusChem ; 12(11): 2415-2420, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-30912291

RESUMO

Great expectation is placed on sodium-ion batteries with high rate capability to satisfy multiple requirements in large-scale energy storage systems. However, the large ionic radius and high mass of Na+ hamper its kinetics in the case of diffusion-controlled mechanisms in conventional electrodes. In this study, a unique intercalation pseudocapacitance has been demonstrated in low-vacancy copper hexacyanoferrate, achieving outstanding rate capability. The minimization of the [Fe(CN)6 ] vacancy enables unhindered diffusion pathways for Na+ and little structural change during the Fe2+ /Fe3+ redox reaction, eliminating solid-state diffusion limits. Moreover, the Cu+ /Cu2+ couple is unexpectedly activated, realizing a record capacity for copper hexacyanoferrate. A capacity of 86 mAh g-1 is obtained at 1 C, of which 50 % is maintained under 100 C and 70 % is achieved at 0 °C. Such intercalation pseudocapacitance might shed light on exploiting high-rate electrodes among Prussian blue analogs for advanced sodium-ion batteries.

6.
J Biomater Appl ; 33(6): 766-775, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30396325

RESUMO

The microstructure, mechanical properties, and in vitro biocompatibility of vacuum-sintered Ti-xZr binary alloys (x = 5, 15, 25, 35, 45 wt%) were investigated. The results indicated that α and α' phase existed in Ti-xZr alloys. The hardness of the Ti-Zr alloys increased as the contents increased and ranged from 473 HV (Ti-5Zr) to 525 HV (Ti-45Zr). Increasing Zr content could lead to an increase in compressive and bending strength. Additionally, the Ti-45Zr alloy exhibited the maximum bending strength of 867.1 MPa and the maximum compressive strength of 1599.8 MPa which were much larger than that of CP-Ti. Moreover, all Ti-Zr alloys showed a lower elastic modulus (ranging from 53.5 to 59.3 GPa) compared with CP-Ti (103 GPa). The in vitro cytotoxicity tests were carried out for biocompatibility evaluation. The alloys presented no cytotoxic effects and the surface of the alloys exhibited great growth conditions for MG-63 cells. The Ti-45Zr alloy exhibited better mechanical properties and biocompatibility. In conclusion, Ti-45Zr alloy is of great potential for dental applications.


Assuntos
Ligas/química , Materiais Biocompatíveis/química , Materiais Dentários/química , Linhagem Celular , Força Compressiva , Módulo de Elasticidade , Dureza , Humanos , Teste de Materiais , Resistência à Tração
7.
iScience ; 3: 110-133, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-30428315

RESUMO

Non-lithium energy storage devices, especially sodium ion batteries, are drawing attention due to insufficient and uneven distribution of lithium resources. Prussian blue and its analogs (Prussian blue analogs [PBAs]), or hexacyanoferrates, are well-known since the 18th century and have been used for hydrogen storage, cancer therapy, biosensing, seawater desalination, and sewage treatment. Owing to their unique features, PBAs are receiving increasing interest in the field of energy storage, such as their high theoretical specific capacity, ease of synthesis, as well as low cost. In this review, a general summary and evaluation of the applications of PBAs for rechargeable batteries are given. After a brief review of the history of PBAs, their crystal structure, nomenclature, synthesis, and working principle in rechargeable batteries are discussed. Then, previous works classified based on the combination of insertion cations and transition metals are analyzed comprehensively. The review includes an outlook toward the further development of PBAs in electrochemical energy storage.

8.
Behav Neurol ; 2018: 4147502, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30018669

RESUMO

We investigated whether Xiao-Xu-Ming decoction reduced mitophagy activation and kept mitochondrial function in cerebral ischemia-reperfusion injury. Rats were randomly divided into 5 groups: sham, ischemia and reperfusion (IR), IR plus XXMD (60 g/kg/day) (XXMD60), IR plus cyclosporin A (10 mg/kg/day) (CsA), and IR plus vehicle (Vehicle). Focal cerebral ischemia and reperfusion models were induced by middle cerebral artery occlusion (MCAO). Cerebral infarct areas were measured by triphenyl tetrazolium chloride staining. Cerebral ischemic injury was evaluated by hematoxylin and eosin staining (HE) and Nissl staining. Ultrastructural features of mitochondria and mitophagy in the penumbra of the ischemic cortex were observed by transmission electron microscopy. Mitophagy was detected by immunofluorescence labeled with LC3B and VDAC1. Autophagy lysosome formation was observed by immunofluorescence labeled with LC3B and Lamp1. The expression of LC3B, Beclin1, and Lamp1 was analyzed by Western blot. The rats subjected to MCAO showed worsened neurological score and cell ischemic damage. These were all significantly reversed by XXMD or CsA. Moreover, XXMD/CsA notably downregulated mitophagy and reduced the increase in LC3, Beclin1, and Lamp1 expression induced by cerebral ischemia and reperfusion. The findings demonstrated that XXMD exerted neuroprotective effect via downregulating LC3, Beclin1, Lamp1, and mitochondrial p62 expression level, thus leading to the inhibition of mitophagy.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Medicina Tradicional Chinesa , Mitocôndrias/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley
9.
Brain Res Bull ; 142: 63-77, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29964088

RESUMO

This study examined the course of mitophagy following cerebral ischemia with reperfusion and the role of the PTEN-induced kinase 1 (PINK1)/Parkin/p62 signalling pathway. The middle cerebral artery of male Sprague-Dawley rats was occluded for 90 min and was followed by different time-points of reperfusion. Cerebral infarct areas were detected by 2,3,5-triphenyl tetrazolium chloride staining, while brain damage was observed by haematoxylin and eosin staining. Levels of LC3, Beclin1 and LAMP-1 were estimated by western blots. LC3B location was observed in various cells in the neurovascular unit. In addition, PINK1 accumulation in damaged mitochondria and Parkin/p62 mitochondrial translocation were investigated by double immunofluorescence staining. Finally, the levels of PINK1, Parkin and p62 expression in mitochondrial fractions were estimated by western blots. Cerebral ischemia with different time-points of reperfusion resulted in infarct in the territory of the middle cerebral artery accompanied by overall brain damage. In addition, we found up-regulation of LC3B, Beclin1, and LAMP-1, as well as mitophagy activation after reperfusion, with peak expression of these proteins at 24 h after reperfusion. Electron microscopy and immunofluorescence indicated that LC3B was primarily located in neurons, although lower levels of expression were found in astrocytes and even less in vascular endothelial cells. Moreover, significant increases in PINK1 accumulation in the outer membrane of mitochondria and increased Parkin/p62 mitochondrial translocation were shown at 24 h after reperfusion. These findings suggest that the PINK1/Parkin/p62 signalling pathway was involved in the pathophysiological processes following ischemia and reperfusion.


Assuntos
Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Mitofagia/fisiologia , Traumatismo por Reperfusão/metabolismo , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Autofagia/fisiologia , Encéfalo/patologia , Isquemia Encefálica/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Expressão Gênica , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neurônios/metabolismo , Neurônios/patologia , Proteínas Quinases/metabolismo , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais , Fatores de Tempo , Ubiquitina-Proteína Ligases/metabolismo
10.
Molecules ; 23(1)2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29320439

RESUMO

A series of novel oleanolic acid 3-O-ß-d-glucuronopyranoside derivatives have been designed and synthesized. Biological evaluation has indicated that some of the synthesized compounds exhibit moderate to good activity against H2O2-induced injury in rat myocardial cells (H9c2). Particularly, derivative 28-N-isobutyl ursolic amide 3-O-ß-d-galactopyranoside (8a) exhibited a greater protective effect than the positive control oleanolic acid 3-O-ß-d-glucuronopyranoside, indicating that it possesses a great potential for further development as a cardiovascular disease modulator by structural modification.


Assuntos
Mioblastos Cardíacos/efeitos dos fármacos , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/síntese química , Substâncias Protetoras/síntese química , Substâncias Protetoras/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular , Humanos , Peróxido de Hidrogênio/química , Estrutura Molecular , Mioblastos Cardíacos/patologia , Ácido Oleanólico/farmacologia , Ratos , Relação Estrutura-Atividade
11.
Front Pharmacol ; 8: 862, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29218010

RESUMO

Modulation of apoptosis is therapeutically effective in cardiomyocytes damage. Calenduloside E (CE), a naturally occurring triterpenoid saponin, is a potent anti-apoptotic agent. However, little is known about its synthetic analogues on the protective effects in apoptosis of cardiomyocytes. The present research was performed to investigate the potential protective effect of CE analogues against H2O2-induced apoptosis in H9c2 cardiomyocytes and the underlying mechanisms. Sixteen novel CE anologues have been designed, synthesized and biological evaluation. Among the 16 CE anologues, as well as the positive control CE tested, compound 5d was the most effective in improving cardiomyocytes viability. Pretreatment with anologue 5d inhibited ROS generation, maintained the mitochondrial membrane potential and reduced apoptotic cardiomyocytes. Moreover, exposure to H2O2 significantly increased the levels of Bax, cleaved caspase-3, and cleaved PARP, and decreased the level of Bcl-2, resulting in cell apoptosis. Pretreatment with anologue 5d (0.02-0.5 µg/mL) dose-dependently upregulated antiapoptotic proteins and downregulated proapoptotic proteins mentioned above during H2O2-induced apoptosis. These results suggested that CE analogues provide protection to H9c2 cardiomyocytes against H2O2-induced oxidative stress and apoptosis, most likely via anti-apoptotic mechanism, and provided the basis for the further optimization of the CE analogues.

12.
Huan Jing Ke Xue ; 29(11): 3213-8, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19186830

RESUMO

The aging processes of copper and zinc in single and combined metal-contaminated typical soils of China, red soil, paddy soil and cinnamon soil, were studied. The results showed that available copper and zinc (metals extracted by 0.01 mol x L(-1) CaCl2 ) decreased rapidly at initial stages, and then reduced slowly, where the turning point occurred at about 90 d. The difference in aging of copper and zinc was insignificant whether in single metal-contaminated soils or in combined metal-contaminated soils, suggested there were similar chemical behaviors between copper and zinc. The aging processes of copper and zinc in red soil, paddy soil and cinnamon soil fitted best a second-order equation (R2 = 0.9940-0.9999, p < 0.0001), whereas parabolic diffusion equation has less goodness of fit. It indicated that the transformation from availability to unavailability of metals, i.e. aging, was not completely controlled by diffusion, but controlled by the interactions from surface nucleation/precipitation, occlusion by organic matter, and diffusion, etc. The aging of copper and zinc in soils was significantly affected by pH. In soils with low pH such as red soil, the ratio of available metals was higher and the aging rate was slower [constant of rate, k2 4.36x10(-3)-7.05x10(-3) kg x (mg x d)(-1)]; whereas in soils with high pH, for example in cinnamon soil, the ratio of available metals was lower and the aging rate was faster [k2 1.095x10(-2)-1.377x10(-2) kg x (mg x d)(-1)]. That is, the aging rate of metals in soils increased obviously with increasing pH.


Assuntos
Cobre/química , Poluentes do Solo/química , Solo/análise , Zinco/química , China , Cobre/análise , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Poluentes do Solo/análise , Zinco/análise
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