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1.
Biochem Biophys Res Commun ; 715: 149963, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38676999

RESUMO

Keloids represent a prevalent dermal fibroproliferative disorder. They only affect humans and exhibit several tumor characteristics, such as excessive extracellular matrix (ECM) deposition, which usually occurs after skin injury. Kreotoxin type A (KTA) can inhibit the release of acetylcholine, and thereby inhibit the proliferation of keloid fibroblasts and reducing the formation of scars. Thus, KTA could be used as a therapeutic agent for keloids. However, the mechanisms of action of KTA in keloid treatment remain unclear. In this study, we aimed to explore the underlying mechanisms of action of KTA in human keloid treatment using human tissue and a cell-based model. Integrative microarray analysis revealed that hypoxia-inducible factor 1-alpha (HIF-1α) expression was frequently upregulated in hypertrophic scar and keloid tissues, whereas it was downregulated in the KTA-treated samples. Furthermore, KTA addition to keloid-derived fibroblasts (KDFs) reduced the growth rate and viability, induced apoptosis, and decreased inflammation and oxidative stress in KDFs. However, overexpression of HIF-1α restored cell number and survival, decreased apoptosis, and promoted inflammation and oxidative stress in KTA-treated KDFs. Furthermore, KTA treatment reduced the expression of ECM proteins, including vascular endothelial growth factor (VEGF), collagen I and III, whereas HIF-1α overexpression abolished the effects of KTA on KDFs. In conclusion, our findings provide novel insights into the mechanisms of action of KTA as a potential therapeutic agent for keloids via modulating HIF-1α expression.


Assuntos
Proliferação de Células , Regulação para Baixo , Fibroblastos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Inflamação , Queloide , Humanos , Queloide/metabolismo , Queloide/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/patologia , Inflamação/genética , Células Cultivadas , Apoptose/efeitos dos fármacos
2.
Sci Prog ; 106(2): 368504231180089, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37306207

RESUMO

The development of tunneling equipment still lags behind, limiting rapid and accurate tunneling and restricting efficient production in coal mines. Thus, improving the reliability and design of roadheaders becomes essential. As the shovel plate is an essential part of a roadheader, improving its parameters can increase the roadheader performance. The parameter optimization of roadheader shovel plate is multi-objective optimization. Because of conventional multiobjective optimization requires strong prior knowledge, often provides low-quality results, and presents vulnerability to initialization and other shortcomings when used in practice. We propose an improved particle swarm optimization (PSO) algorithm that takes the minimum Euclidean distance from a base value as the evaluation criterion for global and individual extreme values. The improved algorithm enables multiobjective parallel optimization by providing a non-inferior solution set. Then, the optimal solution is searched in this set using grey decision to obtain the optimal solution. To validate the proposed method, the multiobjective optimization problem of the shovel-plate parameters is formulated for its solution. Before optimization shovel-plate most important parameters l is the width of the shovel plate l = 3.2 m, ß is the inclination angle of the shovel plate and ß = ,19°. When doing optimization, set accelerated factor c1=c2=2, population size N = 20, and maximum number of iterations Tmax = 100. In addition, speed V was restricted by V=Vimax-Vimin, and inertia factor W was dynamic and linearly decreasing, w(t)=wmin+wmax-wminN(N-t), with wmax=0.9 and wmin=0.4. In addition, r1 and r2 were set randomly in [0, 1], while optimization degree η was set to 30%. And then we executed the improved PSO, obtaining 2000 non-inferior solutions. Apply grey decision to find the optimal solution. The optimal roadheader shovel-plate parameters are l = 3.144 m and ß = 16.88°. Comparative analysis is made before and after optimization, the optimized parameters were substituted into the model and simulated. Obtained that the optimized parameters of shovel-plate can reduce the mass of the shovel plate decreases by 14.3%, while the propulsive resistance decreases by 6.62%, and the load capacity increases by 3.68%. Thus jointly achieving the optimization goals of reducing the propulsive resistance while increasing the load capacity. The feasibility of the proposed multiobjective optimization method with improved particle swarm optimization and grey decision is verified, and the method can provide convenient multiobjective optimization in engineering practice.

3.
Int J Mol Sci ; 24(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37108682

RESUMO

Naphthoquinone (1,4-NQ) and its derivatives (NQs, juglone, plumbagin, 2-methoxy-1,4-NQ, and menadione) have a variety of therapeutic applications, many of which are attributed to redox cycling and the production of reactive oxygen species (ROS). We previously demonstrated that NQs also oxidize hydrogen sulfide (H2S) to reactive sulfur species (RSS), potentially conveying identical benefits. Here we use RSS-specific fluorophores, mass spectroscopy, EPR and UV-Vis spectrometry, and oxygen-sensitive optodes to examine the effects of thiols and thiol-NQ adducts on H2S-NQ reactions. In the presence of glutathione (GSH) and cysteine (Cys), 1,4-NQ oxidizes H2S to both inorganic and organic hydroper-/hydropolysulfides (R2Sn, R=H, Cys, GSH; n = 2-4) and organic sulfoxides (GSnOH, n = 1, 2). These reactions reduce NQs and consume oxygen via a semiquinone intermediate. NQs are also reduced as they form adducts with GSH, Cys, protein thiols, and amines. Thiol, but not amine, adducts may increase or decrease H2S oxidation in reactions that are both NQ- and thiol-specific. Amine adducts also inhibit the formation of thiol adducts. These results suggest that NQs may react with endogenous thiols, including GSH, Cys, and protein Cys, and that these adducts may affect both thiol reactions as well as RSS production from H2S.


Assuntos
Sulfeto de Hidrogênio , Naftoquinonas , Compostos de Sulfidrila/química , Tiossulfatos , Cisteína/metabolismo , Sulfeto de Hidrogênio/química , Oxirredução , Glutationa/metabolismo , Proteínas/metabolismo , Oxigênio , Naftoquinonas/metabolismo
4.
Microorganisms ; 11(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36677495

RESUMO

Acetoin is an important four-carbon platform chemical with versatile applications. Optically pure (R)-acetoin is more valuable than the racemate as it can be applied in the asymmetric synthesis of optically active α-hydroxy ketone derivatives, pharmaceuticals, and liquid crystal composites. As a cytotoxic solvent, acetoin at high concentrations severely limits culture performance and impedes the acetoin yield of cell factories. In this study, putative genes that may improve the resistance to acetoin for Escherichia coli were screened. To obtain a high-producing strain, the identified acetoin-resistance gene was overexpressed, and the synthetic pathway of (R)-acetoin was strengthened by optimizing the copy number of the key genes. The engineered E. coli strain GXASR-49RSF produced 81.62 g/L (R)-acetoin with an enantiomeric purity of 96.5% in the fed-batch fermentation using non-food raw materials in a 3-L fermenter. Combining the systematic approach developed in this study with the use of low-cost feedstock showed great potential for (R)-acetoin production via this cost-effective biotechnological process.

5.
Int J Mol Sci ; 23(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36362080

RESUMO

1,4-Napththoquinones (NQs) are clinically relevant therapeutics that affect cell function through production of reactive oxygen species (ROS) and formation of adducts with regulatory protein thiols. Reactive sulfur species (RSS) are chemically and biologically similar to ROS and here we examine RSS production by NQ oxidation of hydrogen sulfide (H2S) using RSS-specific fluorophores, liquid chromatography-mass spectrometry, UV-Vis absorption spectrometry, oxygen-sensitive optodes, thiosulfate-specific nanoparticles, HPLC-monobromobimane derivatization, and ion chromatographic assays. We show that NQs, catalytically oxidize H2S to per- and polysulfides (H2Sn, n = 2−6), thiosulfate, sulfite and sulfate in reactions that consume oxygen and are accelerated by superoxide dismutase (SOD) and inhibited by catalase. The approximate efficacy of NQs (in decreasing order) is, 1,4-NQ ≈ juglone ≈ plumbagin > 2-methoxy-1,4-NQ ≈ menadione >> phylloquinone ≈ anthraquinone ≈ menaquinone ≈ lawsone. We propose that the most probable reactions are an initial two-electron oxidation of H2S to S0 and reduction of NQ to NQH2. S0 may react with H2S or elongate H2Sn in variety of reactions. Reoxidation of NQH2 likely involves a semiquinone radical (NQ·−) intermediate via several mechanisms involving oxygen and comproportionation to produce NQ and superoxide. Dismutation of the latter forms hydrogen peroxide which then further oxidizes RSS to sulfoxides. These findings provide the chemical background for novel sulfur-based approaches to naphthoquinone-directed therapies.


Assuntos
Sulfeto de Hidrogênio , Naftoquinonas , Tiossulfatos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Oxirredução , Naftoquinonas/farmacologia , Naftoquinonas/metabolismo , Sulfeto de Hidrogênio/metabolismo , Enxofre/metabolismo , Oxigênio/metabolismo
6.
Am J Transl Res ; 14(3): 1714-1720, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35422918

RESUMO

OBJECTIVE: To compare the clinical efficacy, safety, and prognosis of full-threaded headless cannulated compression screws (HCCSs) and anatomical plates (APs) in the treatment of triplane fractures of the distal tibia. METHODS: In this retrospective study, 74 patients with triplane fractures of the distal tibia treated in our hospital from April 2017 to March 2019 were selected as the research subjects. Among them, 38 patients receiving full-threaded HCCSs were assigned to the research group (RG), and the remaining 36 patients receiving APs were assigned to the control group (CG). The general indices, including operation, fracture healing, and ambulation times, efficacy, and complications were recorded and compared between the two groups. Visual analogue scale (VAS) was applied to assess pain, and a quality of life (QOL) survey was conducted at 6 months after surgery. RESULTS: Compared with the CG, the operation time, fracture healing time, and ambulation time of the RG were significantly shortened (P<0.05). The proportion of patients with excellent and good outcomes and Mazur Scores in the RG were higher than those in the CG (P<0.05). The frequency of complications in the RG was lower than that in the CG (P<0.05). The preoperative VAS score did not exhibit significant differences between the two groups (P<0.05), but the scores in the RG at T1 and T2 were significantly lower than those in the CG (P<0.001). The QOL score in the RG (76.17±8.57) was also significantly higher than in the CG (71.54±8.02) (P<0.05). CONCLUSION: Full-threaded HCCSs are more effective and safer than APs and can effectively improve the prognosis of patients with triplane fractures of the distal tibia.

7.
Drug Deliv ; 29(1): 637-651, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35188021

RESUMO

Pulmonary inhalation administration is an ideal approach to locally treat lung disease and to achieve systemic administration for other diseases. However, the complex nature of the structural characteristics of the lungs often results in the difficulty in the development of lung inhalation preparations. Nanocrystals technology provides a potential formulation strategy for the pulmonary delivery of poorly soluble drugs, owing to the decreased particle size of drug, which is a potential approach to overcome the physiological barrier existing in the lungs and significantly increased bioavailability of drugs. The pulmonary inhalation administration has attracted considerable attentions in recent years. This review discusses the barriers for pulmonary drug delivery and the recent advance of the nanocrystals in pulmonary inhalation delivery. The presence of nanocrystals opens up new prospects for the development of novel pulmonary delivery system. The particle size control, physical instability, potential cytotoxicity, and clearance mechanism of inhaled nanocrystals based formulations are the major considerations in formulation development.


Assuntos
Portadores de Fármacos/farmacocinética , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Administração por Inalação , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica/métodos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Liofilização/métodos , Macrófagos Alveolares/metabolismo , Nanopartículas/química , Tamanho da Partícula , Surfactantes Pulmonares/farmacologia , Solubilidade , Tecnologia Farmacêutica/métodos
8.
Free Radic Biol Med ; 182: 119-131, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35202787

RESUMO

In the canonical pathway for mitochondrial H2S oxidation electrons are transferred from sulfide:quinone oxidoreductase (SQR) to complex III via ubiquinone (CoQ10). We previously observed that a number of quinones directly oxidize H2S and we hypothesize that CoQ10 may have similar properties. Here we examine H2S oxidation by CoQ10 and more hydrophilic, truncated forms, CoQ1 and CoQ0, in buffer using H2S and polysulfide fluorophores (AzMC and SSP4), silver nanoparticles to measure thiosulfate (H2S2O3), mass spectrometry to identify polysulfides and O2-sensitive optodes to measure O2 consumption. We show that all three quinones concentration-dependently catalyze the oxidization of H2S to polysulfides and thiosulfate in buffer with the potency CoQ0>CoQ1>CoQ10 and that CoQ0 specifically oxidizes H2S to per-polysulfides, H2S2,3,4. These reactions consume and require oxygen and are augmented by addition of SOD suggesting that the quinones, not superoxide, oxidize H2S. Related quinones, MitoQ, menadione and idebenone, oxidize H2S in similar reactions. Exogenous CoQ0 decreases cellular H2S and increases polysulfides and thiosulfate production and this is also O2-dependent, suggesting that the quinone has similar effects on sulfur metabolism in cells. Collectively, these results suggest an additional endogenous mechanism for H2S metabolism and a potential therapeutic approach in H2S-related metabolic disorders.


Assuntos
Sulfeto de Hidrogênio , Nanopartículas Metálicas , Sulfeto de Hidrogênio/metabolismo , Oxirredução , Quinonas , Prata , Sulfetos/metabolismo , Tiossulfatos , Ubiquinona/metabolismo
9.
Ann Transl Med ; 10(24): 1350, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36660693

RESUMO

Background: Post-stroke depression (PSD) is one of the most common and serious sequelae of stroke. The pathogenesis of PSD involves both psychosocial and biological mechanisms, and aerobic exercise is a potential therapeutic target. We conducted an in-depth exploration of the protective mechanisms of aerobic exercise in a PSD mouse model. Methods: In this study, C57BL/6 mice were used as the research objects, and a PSD mouse model was established by combining middle cerebral artery occlusion and chronic unpredictable mild stimulation. Real-time quantitative polymerase chain reaction, enzyme-linked immunosorbent assays, adeno-associated virus microinjection technology, co-immunoprecipitation, fluorescence in-situ hybridization, and western blotting were performed. A moderate-load treadmill exercise was used for aerobic exercise intervention. The moderate-intensity aerobic exercise training method adopted 0 slopes and treadmill adaptation training for 5 days. We verified the effects of aerobic exercise on the nuclear factor kappa B (NF-κB)/nucleotide-binding oligomerization domain--like receptor protein 3 (NLRP3) inflammasome/5-hydroxytryptamine (5-HT) pathway. Results: Aerobic exercise effectively alleviated the neurological damage caused by PSD (P<0.01). The results from the PSD mouse model in vivo were consistent with those of the cell experiments. Moreover, overexpression of irisin improves depression-like behavior in PSD mice. We confirmed that aerobic exercise is involved in PSD through 5-HT, which inhibits NF-κB/NLRP3 inflammasome initiation through irisin and alleviates mitochondrial damage under stress by reducing calcium overload, thereby inhibiting NLRP3 inflammasome activation. Conclusions: Aerobic exercise reversed the NF-κB/NLRP3 inflammasome/5-HT pathway by upregulating irisin expression to alleviate PSD.

10.
Front Bioeng Biotechnol ; 9: 792023, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35145961

RESUMO

2,3,5,6-Tetramethylpyrazine (TMP) is an active pharmaceutical ingredient originally isolated from Ligusticum wallichii for curing cardiovascular and cerebrovascular diseases and is widely used as a popular flavoring additive in the food industry. Hence, there is a great interest in developing new strategies to produce this high-value compound in an ecological and economical way. Herein, a cost-competitive combinational approach was proposed to accomplish green and high-efficiency production of TMP. First, microbial cell factories were constructed to produce acetoin (3-hydroxy-2-butanone, AC), an endogenous precursor of TMP, by introducing a biosynthesis pathway coupled with an intracellular NAD+ regeneration system to the wild-type Escherichia coli. To further improve the production of (R)-AC, the metabolic pathways of by-products were impaired or blocked stepwise by gene manipulation, resulting in 40.84 g/L (R)-AC with a high optical purity of 99.42% in shake flasks. Thereafter, an optimal strain designated GXASR11 was used to convert the hydrolysates of inexpensive feedstocks into (R)-AC and achieved a titer of 86.04 g/L within 48 h in a 5-L fermenter under optimized fermentation conditions. To the best of our knowledge, this is the highest (R)-AC production with high optical purity (≥98%) produced from non-food raw materials using recombinant E. coli. The supernatant of fermentation broth was mixed with diammonium phosphate (DAP) to make a total volume of 20 ml and transferred to a high-pressure microreactor. Finally, 56.72 g/L TMP was obtained in 3 h via the condensation reaction with a high conversion rate (85.30%) under optimal reaction conditions. These results demonstrated a green and sustainable approach to efficiently produce high-valued TMP, which realized value addition of low-cost renewables.

11.
JCI Insight ; 5(10)2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32434992

RESUMO

NOD-like receptor 12 (NLRP12) is a member of the nucleotide-binding domain and leucine-rich repeat containing receptor inflammasome family that plays a central role in innate immunity. We previously showed that DNA damage upregulated NLRP12 in hematopoietic stem cells (HSCs) of mice deficient in the DNA repair gene Fanca. However, the role of NLRP12 in HSC maintenance is not known. Here, we show that persistent DNA damage-induced NLRP12 improves HSC function in both mouse and human models of DNA repair deficiency and aging. Specifically, treatment of Fanca-/- mice with the DNA cross-linker mitomycin C or ionizing radiation induces NLRP12 upregulation in phenotypic HSCs. NLRP12 expression is specifically induced by persistent DNA damage. Functionally, knockdown of NLRP12 exacerbates the repopulation defect of Fanca-/- HSCs. Persistent DNA damage-induced NLRP12 was also observed in the HSCs from aged mice, and depletion of NLRP12 in these aged HSCs compromised their self-renewal and hematopoietic recovery. Consistently, overexpression of NLRP12 substantially improved the long-term repopulating function of Fanca-/- and aged HSCs. Finally, persistent DNA damage-induced NLRP12 maintains the function of HSCs from patients with FA or aged donors. These results reveal a potentially novel role of NLRP12 in HSC maintenance and suggest that NLRP12 targeting has therapeutic potential in DNA repair disorders and aging.


Assuntos
Envelhecimento/metabolismo , Dano ao DNA , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Envelhecimento/genética , Envelhecimento/patologia , Animais , Proteína do Grupo de Complementação A da Anemia de Fanconi/deficiência , Proteína do Grupo de Complementação A da Anemia de Fanconi/metabolismo , Células-Tronco Hematopoéticas/patologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Knockout
12.
Leukemia ; 34(11): 3028-3041, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32366935

RESUMO

Cyclooxygenase (COX)-dependent production of prostaglandins (PGs) is known to play important roles in tumorigenesis. PGD2 has recently emerged as a key regulator of tumor- and inflammation-associated functions. Here we show that mesenchymal stromal cells (MSCs) from patients with acute myeloid leukemia (AML) or normal MSCs overexpressing COX2 promote proliferation of co-cultured hematopoietic stem and progenitor cells (HSPCs), which can be prevented by treatment with COX2 knockdown or TM30089, a specific antagonist of the PGD2 receptor CRTH2. Mechanistically, we demonstrate that PGD2-CRTH2 signaling acts directly on type 2 innate lymphoid cells (ILC2s), potentiating their expansion and driving them to produce Interleukin-5 (IL-5) and IL-13. Furthermore, IL-5 but not IL-13 expands CD4+CD25+IL5Rα+ T regulatory cells (Tregs) and promotes HSPC proliferation. Disruption of the PGD2-activated ILC2-Treg axis by specifically blocking the PGD2 receptor CRTH2 or IL-5 impedes proliferation of normal and malignant HSPCs. Conversely, co-transfer of CD4+CD25+IL5Rα+ Tregs promotes malignant HSPC proliferation and accelerates leukemia development in xenotransplanted mice. Collectively, these results indicate that the mesenchymal source of PGD2 promotes proliferation of normal and malignant HSPCs through activation of the ILC2-Treg axis. These findings also suggest that this novel PGD2-activated ILC2-Treg axis may be a valuable therapeutic target for cancer and inflammation-associated diseases.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Imunidade Inata , Linfócitos/imunologia , Linfócitos/metabolismo , Células-Tronco Neoplásicas/metabolismo , Prostaglandina D2/metabolismo , Biomarcadores , Células Cultivadas , Técnicas de Cocultura , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Neoplasias Hematológicas/etiologia , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patologia , Humanos , Interleucina-5/metabolismo , Ativação Linfocitária , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neoplásicas/patologia , Receptores Imunológicos/genética , Receptores de Prostaglandina/genética , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
13.
Stem Cells ; 38(6): 756-768, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32129527

RESUMO

The transcriptional repressor Hairy Enhancer of Split 1 (HES1) plays an essential role in the development of many organs by promoting the maintenance of stem/progenitor cells, controlling the reversibility of cellular quiescence, and regulating both cell fate decisions. Deletion of Hes1 in mice results in severe defects in multiple organs and is lethal in late embryogenesis. Here we have investigated the role of HES1 in hematopoiesis using a hematopoietic lineage-specific Hes1 knockout mouse model. We found that while Hes1 is dispensable for steady-state hematopoiesis, Hes1-deficient hematopoietic stem cells (HSCs) undergo exhaustion under replicative stress. Loss of Hes1 upregulates the expression of genes involved in PPARγ signaling and fatty acid metabolism pathways, and augments fatty acid oxidation (FAO) in Hes1 f/f Vav1Cre HSCs and progenitors. Functionally, PPARγ targeting or FAO inhibition ameliorates the repopulating defects of Hes1 f/f Vav1Cre HSCs through improving quiescence in HSCs. Lastly, transcriptome analysis reveals that disruption of Hes1 in hematopoietic lineage alters expression of genes critical to HSC function, PPARγ signaling, and fatty acid metabolism. Together, our findings identify a novel role of HES1 in regulating stress hematopoiesis and provide mechanistic insight into the function of HES1 in HSC maintenance.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Fatores de Transcrição HES-1/deficiência , Animais , Diferenciação Celular , Camundongos
14.
Eur J Pharm Sci ; 110: 77-86, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28167234

RESUMO

In our previous study, Rhizoma Coptidis extract was found to exert more potent inhibitory effect than its major component berberine towards urease from Helicobacter pylori (HPU) and jack bean (JBU). In continuation of our work, the present study was designed to further comparatively investigate the urease inhibitory activities of five major protoberberine alkaloids in Rhizoma Coptidis, namely berberine, palmatine, coptisine, epiberberine, jateorhizine to identify the bioactive constituent, and illuminate the potential mechanism of action. Results indicated that the five protoberberine alkaloids acted as concentration-dependent inactivators of urease with IC50 values ranging between 3.0 and 5087µM for HPU and 2.3->10,000µM for JBU, respectively. Notably, epiberberine (EB) was found to be the most potent inhibitor against both ureases with IC50 values of 3.0±0.01µM for HPU and 2.3±0.01µM for JBU, which was more effective than the standard urease inhibitor, acetohydroxamic acid (83±0.01µM for HPU and 22±0.01µM for JBU, respectively). Further kinetic analysis revealed that the type of EB inhibition against HPU was slow-binding and uncompetitive, with Ki of 10.6±0.01µM, while slow-binding and competitive against JBU with Ki of 4.6±0.01µM. Addition of thiol reagents, such as l-cysteine, glutathione and dithiothreitol, significantly abolished the inhibition, while Ni2+ competitive inhibitors, boric acid and sodium fluoride, synergetically inhibited urease with EB, indicating the obligatory role of the active site sulfhydryl group for the inhibition. In addition, binding of EB with the urease proved to be reversible, as about 65% and 90% enzymatic activity of HPU and JBU, respectively, could be restored by dithiothreitol application. These findings highlighted the potential role of Rhizoma Coptidis protoberberine alkaloids, especially EB, as a lead urease inhibitor in the treatment of diseases associated with ureolytic bacteria. Thus, EB had good potential for further development into a promising therapeutic approach for the treatment of urease-related diseases.


Assuntos
Berberina/análogos & derivados , Proteínas de Plantas/antagonistas & inibidores , Urease/antagonistas & inibidores , Berberina/química , Canavalia/enzimologia , Coptis chinensis , Cisteína/química , Ditiotreitol/química , Medicamentos de Ervas Chinesas/química , Glutationa/química , Helicobacter pylori/enzimologia , Ácidos Hidroxâmicos/química , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Urease/química
15.
J Biomed Mater Res A ; 100(3): 646-53, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22213420

RESUMO

In this study, a new functionalized peptide RLN was designed containing the bioactive motif link N, the amino terminal peptide of link protein. A link N nanofiber scaffold (LN-NS) was self-assembled by mixing peptide solution of RLN and RADA16. The characterization of LN-NS was tested using atomic force microscopy (AFM). The biocompatibility and bioactivity of this nanofiber scaffold for rabbit nucleus pulposus cells (NPCs) were also evaluated. This designer functionalized nanofiber scaffold exhibited little cytotoxicity and promoted NPCs adhesion obviously. In three-dimensional cell culture experiments, confocal reconstructed images testified that the functionalized LN-NS-guided NPCs migration from the surface into the hydrogel considerably, in which the RADA16 scaffold did not. Moreover, the functionalized LN-NS significantly stimulated the biosynthesis of extracelluar matrices (ECM) by NPCs. Our findings demonstrate that the functionalized nanofiber scaffold containing link N had excellent biocompatibility and bioactivity with rabbit NPCs and could be useful in the nucleus pulposus regeneration.


Assuntos
Hidrogéis/química , Disco Intervertebral/citologia , Nanofibras/química , Peptídeos/química , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Adesão Celular , Técnicas de Cultura de Células/métodos , Células Cultivadas , Masculino , Teste de Materiais , Microscopia de Força Atômica , Coelhos , Engenharia Tecidual/métodos
16.
Zhongguo Zhong Yao Za Zhi ; 35(13): 1670-3, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20862953

RESUMO

OBJECTIVE: To investigate 4 populations of 80 samples of Vitex trifolia var. simplicifolia collected from Shandong and Jiangxi province and analyze their intraspecies genetic variance. METHOD: Inter-simple sequence repeat (ISSR) technique was applied for the study. RESULT: Fifteen specific and stable primers were selected from 100 primers. A total of 129 sites were generated, and 115 of them (89.15%) were polymorphic. The data analyzed by PopGene demonstrated that the average polymorphic site percentage among the four populations was 71.89%. The average Shannon's information index was 0. 220 4. According to cluster analysis and the law of geographic variation, the populations were classified into two large groups: the Shandong group and the Jiangxi group. CONCLUSION: These results will provide the information for protection and utilization of V. trifolia var. simplicifolia and also further data for the study of genetic variation and species differentiation of V. trifolia var. simplicifolia.


Assuntos
Variação Genética , Vitex/genética , China , Repetições de Microssatélites , Polimorfismo Genético , Vitex/classificação
17.
Artigo em Chinês | MEDLINE | ID: mdl-20187454

RESUMO

OBJECTIVE: To evaluate the clinical outcomes of two different surgical treatments for arachnoid cysts in sacral canal. METHODS: From January 2004 to March 2009, 55 cases of arachnoid cysts in the sacral canal were treated by traditional simple sacral laminectomies with resection of the cysts (group A, 25 cases) and novel CT-guided percutaneous fibrin glue therapy of arachnoid cysts (group B, 30 cases). Of them, there were 23 males and 32 females, aging 15-66 years with an average of 42.6 years; the duration of symptoms was 6 months to 15 years with an average of 3.5 years. L5-S1 was involved in 22 cases, S1,2 in 25 cases, S2,3 in 12 cases, S2 in 8 cases, and presacral in 2 cases. The size of cysts was 1.5 cm x 1.0 cm to 6.0 cm x 2.8 cm. The MRI examination showed that all patients had cysts in the sacral canal. There were no significant difference (P > 0.05) in sex, ages, disease duration and cysts size between two groups. Preoperative data and postoperative lumbosacral pain and function improvement were analyzed and compared between two groups. RESULTS: All operations were performed successfully. The operative time, blood loss and hospitalization days of group B were significantly less than those of group A (P < 0.01). All 55 cases were followed up from 9 to 61 months (mean 23 months). In group A, postoperative cerebrospinal fluid leakage (25 cases), intracranial infection (2 cases), nerve injury (3 cases), and nerve root irritation (8 cases) occurred; in group B, mild meningitis (3 cases) and low grade fever (5 cases) occurred. Except for nerve injury, other complications were cured after symptomatic management. During the follow-up, 2 recurrent cases were found in group A and 1 case in group B. Of them, 2 recurrent cases were treated with CT-guided percutaneous fibrin glue therapy of arachnoid cysts, and cysts disappeared. For two groups, there were significant differences in Oswestry functional disability index and visual analogue scale score between preoperation and postoperation (P < 0.01), and in the rate of score improvement between two groups (P < 0.01). According to the rating scale, the excellent and good rates of pain improvement were 64% in group A and 100% in group B; the excellent and good rates of function improvement were 24% in group A and 97% in group B. CONCLUSION: CT-guided percutaneous fibrin glue therapy for arachnoid cysts in the sacral canal is a mini-invasive, safe, effective, and economical method, it may be better choices for the treatment of arachnoid cysts in the sacral canal.


Assuntos
Cistos Aracnóideos/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos , Neuroendoscopia , Adolescente , Adulto , Idoso , Feminino , Adesivo Tecidual de Fibrina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Adulto Jovem
18.
Zhongguo Zhong Yao Za Zhi ; 33(15): 1884-9, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19007023

RESUMO

OBJECTIVE: To study the relationship between HPLC fingerprint chromatogram and inhibitory effect on respiratory burst of rat PMN of leaves of crataegus L. METHOD: HPLC fingerprint peaks of different species of hawthorn leaves were isolated and used for the effective experiment on the respiratory burst of rat PMN. The mathematic models of the relationship between the area and the effect of fingerprint peaks were established. According to the mathematic models, the HPLC fingerprint were change into bioactive fingerprint (include effective fingerprint and potency fingerprint) with the helps of mathematics, chemometrics, computer program simulation and etc. RESULT: The chromatogram-effect relationship of leaves of crataegus. on respiratory burst of rat PMN was established. According to this relationship, the activities of fourteen samples of leaves of crataegus. were forecasted. It was positive correlation between the expected value and the practical value. And the correlation coefficients was 0.968 (P < 0.01). CONCLUSION: An all-around evaluative system, which includes not only chemical identification but also effective evaluation for traditional Chinese medicine was established. It will provide a new idea for study on fingerprint chromatogram of traditional Chinese medicine.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Crataegus/química , Medicamentos de Ervas Chinesas/farmacologia , Folhas de Planta/química , Explosão Respiratória/efeitos dos fármacos , Animais , Medicamentos de Ervas Chinesas/química , Feminino , Masculino , Ratos , Ratos Sprague-Dawley
19.
Zhong Yao Cai ; 30(3): 285-9, 2007 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-17634033

RESUMO

OBJECTIVE: To compare the analytical method of LC-UV and LC-MS determination of major polyphenolic components in leaves of Crataegus L. METHODS: By high-performance liquid chromatography method with VWD and MSD, Lichropsher C18 column (250 x 4.6 mm I.D., 5 microm); mobile phase consisted of solvent A (acetonitrile) and solvent B (0.05% formic acid) ; elution profile was: 0-12 min 11% to 17% A in B (linear gradient), 12-30 min 17% to 18% A in B (linear gradient), 30-45 min 18% to 40% A in B (linear gradient), 45-60 min 40% to 100% A in B (linear gradient); flow rate was 1.00 ml/min, flow into MSD and VWD by diffluence, column temperature 30 degrees C and the injection volume 10 microl. RESULT: The sensitivity of LC-MS was 10 times more than that of LC-UV, so it is preponderance for microanalysis. Additionally, because LC-MS can identify the component by retention time (t(R)) and m/z, it has high selectivity and exclusion for the determined component. However, the method of LC-UV is simple; the cost is lower; the separate effect is better. So it is preponderance to determine the higher content component, which has better separate effect. CONCLUSION: LC-UV and LC-MS exhibited their own predominance for determination of major polyphenolic components in leaves of Crataegus L. So the detector should be selected according to the determined targets.


Assuntos
Cromatografia Líquida de Alta Pressão , Crataegus/química , Espectrometria de Massas , Espectrofotometria Ultravioleta , Folhas de Planta/química , Solventes
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