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1.
BMC Gastroenterol ; 24(1): 305, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261787

RESUMO

OBJECTIVE: To compare the sex differences of Helicobacter pylori (HP) infection rate and 1-year recurrence rate. METHODS: A cross-sectional study was conducted on the prevalence of HP infection in 81,754 people who underwent physical examination in physical examination centers and outpatient clinics of the Affiliated Hospital of Gansu University of Traditional Chinese Medicine, the Second People's Hospital of Zhangye City, Tianshui City Hospital of Integrated Chinese and Western Medicine, the First and Second Department of The First Hospital of Lanzhou University Physical Examination Center, from March 2010 to December 2019. Among them, 53,771 (65.77%) were males (18-91 years old) and 27,983 (34.23%) were females (18-94 years old). According to age, they were divided into young group, middle-aged group and old group. 1448 asymptomatic infected patients were selected and treated with bismuth-containing quadruple drug eradication therapy for 2 weeks. The eradication rate and recurrence rate after 1 year were compared between males and females. RESULTS: The overall infection rate was 49.59%, including 49.74% in males and 49.3% in females. The risk of infection in young women was lower than that in men (OR = 0.908, 95%CI: 0.868-0.95, P < 0.01), the risk of infection in older women was higher than that in men (OR = 1.137, 95%CI: 1.041-1.243, P < 0.01). The female infection rate was positively correlated with age from 18 to 60, and Spearman's correlation coefficient was 0.825 (P < 0.01). The overall eradication rate was 84.67% in intention-to-treat analysis (ITT) and 88.46% in protocol analysis (PP). The eradication rates of ITT and PP in the older group were 78.38% and 82.27%, respectively, which were lower than 87.25% and 89.39% in the male group (P < 0.05). The 1-year overall recurrence rate was 3.86%, including 2.82% in males and 5.44% in females (P < 0.05), female was a risk factor for recurrence after eradication after controlling for age (OR = 2.177, 95%CI 1.166-4.066, P < 0.05). There were no obvious adverse reactions during the treatment. CONCLUSION: There is a positive linear correlation between HP infection rate and age increase in women. Older women have the characteristics of high HP infection rate, low eradication rate and high recurrence rate.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Recidiva , Humanos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Transversais , Adulto , Idoso , Adolescente , Adulto Jovem , Idoso de 80 Anos ou mais , China/epidemiologia , Fatores Sexuais , Antibacterianos/uso terapêutico , Prevalência , Quimioterapia Combinada , Fatores Etários
2.
Small ; 18(21): e2201766, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35491505

RESUMO

Skin wounds, especially infected chronic wounds, have attracted worldwide attention due to the high prevalence and poor treatment outcomes. Hydrogel dressings with antibacterial ability and immune regulation property are urgently required. Herein, inspired by the grinding treatment of traditional Chinese medicine, mechanical force is introduced to promote the effective molecular collision and accelerate the self-assembly of chitosan (CS) and puerarin (PUE) for fabricating Chinese-herb-based hydrogels. The antibacterial rate of CS@PUE (C@P) hydrogel is more than 95%, and the wound closed rate is twice that of the control group. Interestingly, the rational design of C@P hydrogels with different PUE ratios enables a refined control over hydrogel formation, nanofiber appearance, viscoelastic, physicochemical, and biological properties. The extraordinary antibacterial ability of C@P hydrogels may originate from the nanofiber structure and the improved zeta potential on account of the orientation of amino groups in CS . Thus, the synergistically antibacterial and immune regulation properties of C@P hydrogels kill bacteria and relieve inflammation in the wound bed, ensuring the anti-infection effect, and boosting wound healing. In addition to providing a universal mechanosynthesis of PUE-based hydrogel for wound healing, this finding is expected to increase the attention paid to Chinese herbal medicines in the construction of biomaterials.


Assuntos
Quitosana , Hidrogéis , Antibacterianos/química , Antibacterianos/farmacologia , China , Quitosana/química , Hidrogéis/química , Cicatrização
3.
Small ; 18(39): e2202908, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36008117

RESUMO

Gallbladder cancer is a common malignant tumor of the biliary system with a high fatality rate. Nitinol (Ni-Ti) stents, a standard treatment for prolonging patients' lives, are susceptible to reocclusion and cannot inhibit tumor recurrence because they lack antitumor and antibacterial activity. Herein, an arsenic-loaded layered double-hydroxide film is constructed on Ni-Ti, forming a micro "chemical factory." The LDH plays the role of a "processer" which absorbs highly toxic trivalent arsenic (As(III)) and processes it into lowly toxic pentavalent arsenic (As(V)). It also acts as a "quality-inspector," confining As(III) in the interlayer and releasing only As(V) (the finished product) to the outside. This control mechanism minimizes the toxicity during contact with normal tissue. The acidic microenvironment and overexpression of glutathione in tumor tissues not only accelerates the release of arsenic from the platform but also triggers the in situ transformation of arsenic from lowly toxic As(V) to highly toxic As(III), exerting a strong arsenic-mediated antineoplastic effect. Such a microenvironment-responsive "chemical factory" with arsenic processing and screening functions is expected to prevent tumor overgrowth, metastasis, and bacterial infection and provide new insights into the design of Ni-Ti drug-eluting stents for gallbladder cancer treatment.


Assuntos
Arsênio , Neoplasias da Vesícula Biliar , Ligas , Antibacterianos/farmacologia , Detecção Precoce de Câncer , Neoplasias da Vesícula Biliar/tratamento farmacológico , Glutationa , Humanos , Hidróxidos , Níquel , Titânio , Microambiente Tumoral
4.
Nano Lett ; 19(6): 3480-3489, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31091110

RESUMO

A proper immune response is key for the successful implantation of biomaterials, and designing and fabricating biomaterials to regulate immune responses is the future trend. In this work, three different nanostructures were constructed on the surface of titanium using a hydrothermal method, and through a series of in vitro and in vivo experiments, we found that the aspect ratio of nanostructures can affect the elastic modulus of a material surface and further regulate immune cell behaviors. This work demonstrates that nanostructures with a higher aspect ratio can endow a material surface with a lower elastic modulus, which was confirmed by experiments and theoretical analyses. The deflection of nanostructures under the cell adsorption force is a substantial factor in stretching macrophages to enhance cell adhesion and spreading, further inducing macrophage polarization toward the M1 phenotype and leading to intense immune responses. In contrast, a nanostructure with a lower aspect ratio on a material surface leads to a higher surface elastic modulus, making deflection of the material difficult and creating a surface that is not conducive to macrophage adhesion and spreading, thus reducing the immune response. Moreover, molecular biology experiments indicated that regulation of the immune response by the elastic modulus is primarily related to the NF-κB signaling pathway. These findings suggest that the immune response can be regulated by constructing nanostructural surfaces with the proper elastic modulus through their influence on cell adhesion and spreading, which provides new insights into the surface design of biomaterials.


Assuntos
Módulo de Elasticidade , Macrófagos/imunologia , Nanoestruturas/química , Animais , Adesão Celular , Camundongos , Camundongos Endogâmicos C57BL , Nanoestruturas/ultraestrutura , Células RAW 264.7 , Propriedades de Superfície
6.
Biochim Biophys Acta ; 1830(6): 3635-42, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23428571

RESUMO

BACKGROUND: Mevalonate pathway is an important cellular metabolic pathway present in all higher eukaryotes and many bacteria. Four enzymes in mevalonate pathway, including MVK, PMK, MDD, and FPPS, play important regulatory roles in cholesterol biosynthesis and cell proliferation. METHODS: The following methods were used: cloning, expression and purification of enzymes in mevalonate pathway, organic syntheses of multifunctional enzyme inhibitors, measurement of their IC50 values for above four enzymes, kinetic studies of enzyme inhibitions, molecular modeling studies, cell viability tests, and fluorescence microscopy. RESULTS AND CONCLUSIONS: We report our multi-target-directed design, syntheses, and characterization of two blue fluorescent bisphosphonate derivatives compounds 15 and 16 as multifunctional enzyme inhibitors in mevalonate pathway. These two compounds had good inhibition to all these four enzymes with their IC50 values at nanomolar to micromolar range. Kinetic and molecular modeling studies showed that these two compounds could bind to the active sites of all these four enzymes. The fluorescence microscopy indicated that these two compounds could easily get into cancer cells. GENERAL SIGNIFICANCE: Multifunctional enzyme inhibitors are generally more effective than single enzyme inhibitors, with fewer side effects. Our results showed that these multifunctional inhibitors could become lead compounds for further development for the treatment of soft-tissue tumors and hypercholesteremia.


Assuntos
Proliferação de Células/efeitos dos fármacos , Difosfonatos , Inibidores Enzimáticos , Corantes Fluorescentes , Ácido Mevalônico/metabolismo , Simulação de Acoplamento Molecular , Animais , Sobrevivência Celular/efeitos dos fármacos , Difosfonatos/síntese química , Difosfonatos/química , Difosfonatos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/enzimologia , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Ratos
7.
J Funct Biomater ; 15(1)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38248690

RESUMO

In recent years, rapid advancements in multidisciplinary fields (materials, biology, chemical physics, etc [...].

8.
Sci Rep ; 14(1): 22084, 2024 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333377

RESUMO

To investigate the relationship between long-term use of low-dose aspirin and Helicobacter pylori (HP) infection, and its effect on eradication and recurrence of HP. According to the results of C14-Urea Breath Test (C14-UBT), 3256 patients with cardiovascular and cerebrovascular diseases from March 2019 to December 2020, were divided into HP infection group and non-infection group. Univariate and multivariate was used to investigate the relationship between Low-dose aspirin use and HP infection. 859 patients with hypertension combined with HP infection were divided into aspirin group, non-aspirin group and control group, the eradication rate after 2 weeks of bismuth-containing quadruple drug treatment and the recurrence rate after 1,3 year were compared. The overall infection rate of HP was 53.3%. The results of univariate analysis showed that the infection rate of female, age, BMI, LDL-C, FBG of HP infected group was higher than non-infection. The infection rate of patients who took low-dose aspirin was higher than no-aspirin [56.6% vs. 51.3%, χ2 = 8.548, P = 0.003]. Multivariate Logistic regression analysis showed that long-term aspirin use still increased the risk of infection (OR = 1.433, 95% CI 1.196-1.947, P < 0.001). The Per-Protocol analysis showed that the overall eradication rate was 87.6%, and among the eradication rates of aspirin group, non-aspirin group and control group were not statistically significantly (87.8%, 88.5%, and 86.6%, respectively), The Intention-To-Treat analysis showed that the overall eradication rate was 84.3%, and the eradication rates among the three groups were not statistically significantly. The overall 1-year recurrence rate was 1.3%, and the recurrence rates of the three groups were no statistical significance. The overall 3-years recurrence rate was 3.1%, and the recurrence rate of aspirin group was higher than non-aspirin group and control group (5.30%, 1.90% and 1.70%, respectively, χ2 = 6.118, P < 0.05). The main adverse reactions in the first month of eradication treatment were constipation and mild nausea, and there was no statistical significance between the three groups. Long-term use of low-dose aspirin increases the risk of HP infection and the recurrence rate in 3 years after eradication. It is suggested that HP should be tested and eradicated regularly in long-term users.


Assuntos
Aspirina , Infecções por Helicobacter , Helicobacter pylori , Recidiva , Aspirina/administração & dosagem , Infecções por Helicobacter/tratamento farmacológico , Humanos , Feminino , Masculino , Helicobacter pylori/efeitos dos fármacos , Pessoa de Meia-Idade , Idoso , Testes Respiratórios , Quimioterapia Combinada , Antibacterianos/administração & dosagem
9.
Int Immunopharmacol ; 140: 112828, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39094359

RESUMO

Changes in isocitrate dehydrogenases (IDH) lead to the production of the cancer-causing metabolite 2-hydroxyglutarate, making them a cause of cancer. However, the specific role of IDH in the progression of colon cancer is still not well understood. Our current study provides evidence that IDH2 is significantly increased in colorectal cancer (CRC) cells and actively promotes cell growth in vitro and the development of tumors in vivo. Inhibiting the activity of IDH2, either through genetic silencing or pharmacological inhibition, results in a significant increase in α-ketoglutarate (α-KG), indicating a decrease in the reductive citric acid cycle. The excessive accumulation of α-KG caused by the inactivation of IDH2 obstructs the generation of ATP in mitochondria and promotes the downregulation of HIF-1A, eventually inhibiting glycolysis. This dual metabolic impact results in a reduction in ATP levels and the suppression of tumor growth. Our study reveals a metabolic trait of colorectal cancer cells, which involves the active utilization of glutamine through reductive citric acid cycle metabolism. The data suggests that IDH2 plays a crucial role in this metabolic process and has the potential to be a valuable target for the advancement of treatments for colorectal cancer.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Isocitrato Desidrogenase , Transdução de Sinais , Isocitrato Desidrogenase/metabolismo , Isocitrato Desidrogenase/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Animais , Linhagem Celular Tumoral , Camundongos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Ácidos Cetoglutáricos/metabolismo , Ciclo do Ácido Cítrico , Glicólise , Camundongos Nus , Progressão da Doença , Trifosfato de Adenosina/metabolismo , Proliferação de Células , Reprogramação Celular , Mitocôndrias/metabolismo , Neoplasias Intestinais/patologia , Neoplasias Intestinais/metabolismo , Reprogramação Metabólica
10.
Nanotechnology ; 24(30): 305706, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23843606

RESUMO

Biocompatible and freestanding TiO2 nanotube membranes with improved photocatalytic activity were fabricated through a water-vapour-assisted annealing treatment at relatively low temperatures. Photoluminescence results and structure characterization prove that the obtained TiO2 nanotube membranes not only possess an enhanced anatase crystallinity from water molecule-intermediated dissolution-precipitation reactions, but are also covered with abundant hydroxyl groups which are hardly influenced by external disturbances. The anatase crystallinity, the superficial hydroxyl groups and the nanotubular morphology of the membrane treated with water vapour thus lead to enhancement in photocatalytic activity. This new approach is simple and time-saving, opening up new opportunities in various areas, including tissue-engineering, watersplitting, dye-sensitized solar cells and photocatalysis.


Assuntos
Membranas Artificiais , Nanotubos/química , Titânio/química , Animais , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Teste de Materiais , Células-Tronco Mesenquimais , Nanotubos/ultraestrutura , Processos Fotoquímicos , Ratos , Titânio/farmacologia , Difração de Raios X
11.
J Funct Biomater ; 14(9)2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37754870

RESUMO

Manganese (Mn) is an essential micronutrient in various physiological processes, but its functions in bone metabolism remain undefined. This is partly due to the interplay between immune and bone cells because Mn plays a central role in the immune system. In this study, we utilized the plasma immersion ion implantation and deposition (PIII&D) technique to introduce Mn onto the titanium surface. The results demonstrated that Mn-implanted surfaces stimulated the shift of macrophages toward the M1 phenotype and had minimal effects on the osteogenic differentiation of mouse bone marrow mesenchymal stem cells (mBMSCs) under mono-culture conditions. However, they promoted the M2 polarization of macrophages and improved the osteogenic activities of mBMSCs under co-culture conditions, indicating the importance of the crosstalk between mBMSCs and macrophages mediated by Mn in osteogenic activities. This study provides a positive incentive for the application of Mn in the field of osteoimmunology.

12.
Adv Healthc Mater ; 12(2): e2201367, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36325652

RESUMO

Magnesium (Mg)-based alloys have been regarded as promising implants for future clinic orthopedics, however, how to endow them with good anti-corrosion and biofunctions still remains a great challenge, especially for complicated bone diseases. Herein, three transition metals (M = Mn, Fe, and Co)-containing layered double hydroxides (LDH) (LDH-Mn, LDH-Fe, and LDH-Co) with similar M content are prepared on Mg alloy via a novel two-step method, then systematic characterizations and comparisons are conducted in detail. Results showed that LDH-Mn exhibited the best corrosion resistance, LDH-Mn and LDH-Co possessed excellent photothermal and enzymatic activities, LDH-Fe revealed better cytocompatibility and antibacterial properties, while LDH-Co demonstrated high cytotoxicity. Based on these results, an optimized bilayer LDH coating enriched with Fe and Mn (LDH-MnFe) from top to bottom have been designed for further in vitro and in vivo analysis. The top Fe-riched layer provided biocompatibility and antibacterial properties, while the bottom Mn-riced layer provided excellent anti-corrosion, photothermal and enzymatic effects. In addition, the released Mg, Fe, and Mn ions have a positive influence on angiogenesis and osteogenesis. Thus, the LDH-MnFe showed complementary and synergistic effects on anti-corrosion and multibiofunctions (antibacteria, antitumor, and osteogenesis). The present work offers a novel multifunctional Mg-based implant for treating bone diseases.


Assuntos
Doenças Ósseas , Magnésio , Humanos , Magnésio/farmacologia , Ligas/farmacologia , Hidróxidos , Antibacterianos/farmacologia
13.
ACS Biomater Sci Eng ; 9(7): 4197-4207, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37378535

RESUMO

There is an evident advantage in personalized customization of orthopedic implants by 3D-printed titanium (Ti) and its alloys. However, 3D-printed Ti alloys have a rough surface structure caused by adhesion powders and a relatively bioinert surface. Therefore, surface modification techniques are needed to improve the biocompatibility of 3D-printed Ti alloy implants. In the present study, porous Ti6Al4V scaffolds were manufactured by a selective laser melting 3D printer, followed by sandblasting and acid-etching treatment and atomic layer deposition (ALD) of tantalum oxide films. SEM morphology and surface roughness tests confirmed that the unmelted powders adhered on the scaffolds were removed by sandblasting and acid-etching. Accordingly, the porosity of the scaffold increased by about 7%. Benefiting from the self-limitation and three-dimensional conformance of ALD, uniform tantalum oxide films were formed on the inner and outer surfaces of the scaffolds. Zeta potential decreased by 19.5 mV after depositing tantalum oxide films. The in vitro results showed that the adhesion, proliferation, and osteogenic differentiation of rat bone marrow mesenchymal stem cells on modified Ti6Al4V scaffolds were significantly enhanced, which may be ascribed to surface structure optimization and the compatibility of tantalum oxide. This study provides a strategy to improve the cytocompatibility and osteogenic differentiation of porous Ti6Al4V scaffolds for orthopedic implants.


Assuntos
Osteogênese , Titânio , Ratos , Animais , Titânio/farmacologia , Titânio/química , Pós , Impressão Tridimensional , Ligas
14.
Bioact Mater ; 20: 472-488, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35800406

RESUMO

Implantable biomaterials are widely used in the curative resection and palliative treatment of various types of cancers. However, cancer residue around the implants usually leads to treatment failure with cancer reoccurrence. Postoperation chemotherapy and radiation therapy are widely applied to clear the residual cancer cells but induce serious side effects. It is urgent to develop advanced therapy to minimize systemic toxicity while maintaining efficient cancer-killing ability. Herein, we report a degenerate layered double hydroxide (LDH) film modified implant, which realizes microenvironment-responsive electrotherapy. The film can gradually transform into a nondegenerate state and release holes. When in contact with tumor cells or bacteria, the film quickly transforms into a nondegenerate state and releases holes at a high rate, rendering the "electrocution" of tumor cells and bacteria. However, when placed in normal tissue, the hole release rate of the film is much slower, thus, causing little harm to normal cells. Therefore, the constructed film can intelligently identify and meet the physiological requirements promptly. In addition, the transformation between degenerate and nondegenerate states of LDH films can be cycled by electrical charging, so their selective and dynamic physiological functions can be artificially adjusted according to demand.

15.
Biomater Adv ; 134: 112699, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35581071

RESUMO

Implant infection, undesirable inflammation, and poor osseointegration are the primary reasons for implant failure, so it is pivotal to endow bone implants with antibacterial, anti-inflammatory, and osteogenic properties. Here, a multifunctional fluorine-doped zirconium-metal organic framework (Zr-MOF) film was constructed on the titanium to modify its biological performances. The fumaric acid, a common antioxidant, was selected as the ligand of Zr-MOF, and the hydrofluoric acid was used as the modulator to control the growth of Zr-MOF film. The obtained fluorine-doped Zr-MOF film possessed good biocompatibility and osteogenic ability, and it showed good antibacterial effects against both gram-positive S. aureus and gram-negative E. coli due to the release of fluoride ions. In addition, the doping of fluorine could reduce the stability of Zr-MOF by substituting fumaric acid, and stimulating the releases of fumaric acid. Furthermore, the fumaric acid released from Zr-MOF could down-regulate the expression of pro-inflammatory genes (NF-κB and IL-6), but up-regulate the expression of anti-inflammatory gene of IL-4 of macrophage, showing good anti-inflammatory ability. This study provided a reference for the modulation synthesis of MOF film, and proposed a promising strategy of designing Zr-MOF film to endow bone implants with antibacterial, anti-inflammatory, and osteogenic abilities.


Assuntos
Estruturas Metalorgânicas , Titânio , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Escherichia coli , Fluoretos/farmacologia , Flúor/farmacologia , Estruturas Metalorgânicas/farmacologia , Osteogênese , Staphylococcus aureus , Titânio/farmacologia , Zircônio/farmacologia
16.
Regen Biomater ; 9: rbab076, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35480864

RESUMO

The adverse immune response mediated by macrophages is one of the main factors that are prone to lead poor osseointegration of polyetheretherketone (PEEK) implants in clinic. Hence, endowing PEEK with immunomodulatory ability to avoid the adverse immune response becomes a promising strategy to promote bone repair. In this work, sulfonation and hydrothermal treatment were used to fabricate a 3D porous surface on PEEK and hydroxyapatite (HA) composited PEEK. The HA composited PEEK with 3D porous surface inhibited macrophages polarizing to M1 phenotype and downregulated inducible nitric oxide synthase protein expression, which led to a nitric oxide concentration reduction in culture medium of mouse bone marrow mesenchymal stem cells (mBMSCs) under co-culture condition. The decrease of nitric oxide concentration could help to increase bone formation-related OSX and ALP genes expressions and decrease bone resorption-related MMP-9 and MMP-13 genes expressions via cAMP-PKA-RUNX2 pathway in mBMSCs. In summary, the HA composited PEEK with 3D porous surface has the potential to promote osteogenesis of PEEK through immunomodulation, which provides a promising strategy to improve the bone repair ability of PEEK.

17.
J Funct Biomater ; 13(4)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36412862

RESUMO

Magnesium has been extensively utilized to modify titanium implant surfaces based on its important function in promoting osteogenic differentiation. Autophagy has been proven to play a vital role in bone metabolism. Whether there is an association between autophagy and magnesium in promoting osteogenic differentiation remains unclear. In the present study, we focused on investigating the role of magnesium ions in early osteogenic activity and the underlying mechanism related to autophagy. Different concentrations of magnesium were embedded in micro-structured titanium surface layers using the micro-arc oxidation (MAO) technique. The incorporation of magnesium benefited cell adhesion, spreading, and viability; attenuated intracellular ATP concentrations and p-mTOR levels; and upregulated p-AMPK levels. This indicates the vital role of the ATP-related AMPK/mTOR signaling pathway in the autophagy process associated with osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) induced by magnesium modification on titanium surfaces. The enhanced osteogenic differentiation and improved cellular autophagy activity of BMSCs in their extraction medium further confirmed the function of magnesium ions. The results of the present study advance our understanding of the mechanism by which magnesium regulates BMSC osteogenic differentiation through autophagy regulation. Moreover, endowing implants with the ability to activate autophagy may be a promising strategy for enhancing osseointegration in the translational medicine field in the future.

18.
Acta Biomater ; 153: 494-504, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36115653

RESUMO

The field of nanomedicine-catalyzed tumor therapy has achieved a lot of progress; however, overcoming the limitations of the tumor microenvironment (TME) to achieve the desired therapeutic effect remains a major challenge. In this study, a nanocomposite hydrogel (GH@LDO) platform combining the nanozyme CoMnFe-layered double oxides (CoMnFe-LDO) and natural enzyme glucose oxidase (GOX) was engineered to remodel the TME to enhance tumor catalytic therapy. The CoMnFe-LDO is a nanozyme that can convert endogenous H2O2 into reactive oxygen species (ROS) and O2 to achieve chemodynamic therapy (CDT) and alleviate the hypoxic microenvironment. Meanwhile, GOX can catalyze the conversion of glucose and O2 to gluconic acid and H2O2, which not only represses the ATP production of tumor cells to achieve starvation therapy (ST), but also decreases the pH value of TME and supplies extra H2O2 to enhance the CDT effect. Furthermore, this well-designed CoMnFe-LDO possessed a high photothermal conversion efficiency of GH@LDO (66.63%), which could promote the generation of ROS to enhance the CDT effect and achieve photothermal therapy (PTT) under near-infrared light irradiation. The GH@LDO hydrogel performes cascade reaction which overcomes the limitation of the TME and achieves satisfactory CDT/ST/PTT synergetic effects in vitro and in vivo. This work provides a new strategy for remodeling the TME using nanomedicine to achieve precise tumor cascaded catalytic therapy. STATEMENT OF SIGNIFICANCE: At present, the focus of tumor therapy has begun to shift from monotherapy to combination therapy for improving the overall therapeutic effect. In this study, we synthesized a CoMnFe-LDO nanozyme composed of multiple transition metal oxides, which demonstrated improved peroxidase and oxidase activities as well as favorable photothermal conversion capability. The CoMnFe-LDO nanozyme was compounded with an injectable GH hydrogel crosslinked by GOX and horseradish peroxidase (HRP). This nanocomposite hydrogel overcame the limitations of weak acidity, H2O2, and O2 levels in the TME and achieved synergetic CDT, ST, and PTT effects based on the cascaded catalytic actions of CoMnFe-LDO and GOX to H2O2 and glucose.


Assuntos
Neoplasias , Óxidos , Humanos , Hidrogéis/uso terapêutico , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Terapia Fototérmica , Nanogéis , Linhagem Celular Tumoral , Microambiente Tumoral , Glucose Oxidase , Neoplasias/patologia , Glucose , Reatores Biológicos
19.
Bioorg Med Chem Lett ; 21(22): 6667-73, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21974953

RESUMO

Glutaryl-CoA dehydrogenase catalyzes the oxidative decarboxylation of the γ-carboxylate of the substrate, glutaryl-CoA, to yield crotonyl-CoA and CO(2). The enzyme is a member of the acyl-CoA dehydrogenase (ACD) family of flavoproteins. In the present study, the catalytic properties of this enzyme, including its substrate specificity, isomerase activity, and interactions with inhibitors, were systematically studied. Our results indicated that the enzyme has its catalytic properties very similar to those of short-chain and medium-chain acyl-CoA dehydrogenase except its additional decarboxylation reaction. Therefore, the inhibitors of fatty acid oxidation targeting straight chain acyl-CoA dehydrogenase could also function as inhibitors for amino acid metabolism of lysine, hydroxylysine, and tryptophan.


Assuntos
Acil Coenzima A/metabolismo , Glutaril-CoA Desidrogenase/metabolismo , Acil Coenzima A/antagonistas & inibidores , Acil Coenzima A/química , Sequência de Aminoácidos , Animais , Inibidores Enzimáticos/farmacologia , Glutaril-CoA Desidrogenase/antagonistas & inibidores , Glutaril-CoA Desidrogenase/química , Dados de Sequência Molecular , Ratos , Especificidade por Substrato
20.
Bioact Mater ; 6(1): 191-207, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32913928

RESUMO

Ds-block elements have been gaining increasing attention in the field of biomaterials modification, owing to their excellent biological properties, such as antibiosis, osteogenesis, etc. However, their function mechanisms are not well understood and conflicting conclusions were drawn by previous studies on this issue, which are mainly resulted from the inconsistent experimental conditions. In this work, three most widely used ds-block elements, copper, zinc, and silver were introduced on titanium substrate by plasma immersion ion implantation method to investigate the rule of ds-block elements in the immune responses. Results showed that the implanted samples could decrease the inflammatory responses compared with Ti sample. The trend of anti-inflammatory effects of macrophages on samples was in correlation with cellular ROS levels, which was induced by the implanted biomaterials and positively correlated with the number of valence electrons of ds-block elements. The co-culture experiments of macrophages and bone marrow mesenchymal stem cells showed that these two kinds of cells could enhance the anti-inflammation and osteogenesis of samples by the paracrine manner of PGE2. In general, in their steady states on titanium substrate (Cu2+, Zn2+, Ag), the ds-block elements with more valence electrons exhibit better anti-inflammatory and osteogenic effects. Moreover, molecular biology experiments indicate that the PGE2-related signaling pathway may contribute to the desired immunoregulation and osteoinduction capability of ds-block elements. These findings suggest a correlation between the number of valence electrons of ds-block elements and the relevant biological responses, which provides new insight into the selection of implanted ions and surface design of biomaterials.

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