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1.
J Biomater Appl ; 38(4): 500-508, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37620997

RESUMO

Novel drug delivery system was prepared and evaluated as for application in cancerous bone treatment. It had three stacked layers, including a drug-free layer, a cisplatin-loaded layer, and a curcumin-containing layer. Our previously characterized biomaterials, namely Zr-hydroxyapatite (Zr-HA) and alkaline-treated polycaprolactone (modified-PCL), were used as major components of the drug carrier. Polar-polar interactions between cisplatin and Zr-HA were modulated by the modified-PCL included, leading to increase of cisplatin release. Using ß-cyclodextrin (ß-CD) to entrap curcumin caused improvement of curcumin solubility and release. The 3D-construct was porous with internal interconnected pores according to SEM micrographs. Large amount of apatite was formed and proteins adsorbed on the scaffolds after immersed in physiologic buffer solution and in medium containing fetal bovine serum, respectively. Optimal concentrations of ascorbic acid and triamcinolone were used for induction of bone marrow stromal cells to become osteoblasts by expressing an enzyme marker, e.g., alkaline phosphatase. The prepared scaffolds were considered osteo-conductive and osteo-inductive. The concentrations of cisplatin and curcumin reached the IC50 of SK-ES-1 cells of osteosarcoma and MCF-7 cells of breast adenocarcinoma after 24 h and 3 days of release, respectively. These cancer cells were more sensitive to the combined cisplatin and curcumin than each of the drugs. Regeneration of new bone and execution of residential cancer cells in defected bone were proposed after replacing the lost bone by this established drug carrier. The assumption needs to be verified in the future using animal models.


Assuntos
Neoplasias Ósseas , Curcumina , Animais , Alicerces Teciduais , Curcumina/farmacologia , Cisplatino/farmacologia , Poliésteres/farmacologia , Regeneração Óssea , Durapatita/farmacologia , Portadores de Fármacos
2.
PeerJ ; 9: e11618, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34221723

RESUMO

BACKGROUND: A bisresorcinol was isolated as the main constituent of Heliciopsis terminalis's trunk (Proteaceae). Recently, resorcinol is applied as an active whitening agent in various cosmetic products. Because of the structural mimic to resorcinol, benefits of the bisresorcinol as an aging-enzyme antagonist were demonstrated in this study. METHODS: The bisresorcinol was purified from the crude ethanolic extract of H. terminalis's trunk by solvent extraction and preparative chromatography, respectively. Inhibitory activity on collagenase, elastase, and tyrosinase of the compound was investigated by using a different spectroscopic technique. Molecular docking was carried out to predict possible interactions of the substance around the enzyme active sites. RESULTS: The IC50 values on collagenase of the bisresorcinol and caffeic acid were 156.7 ± 0.7 and 308.9 ± 1.6 µmole L-1, respectively. For elastase activity, the IC50 of 33.2 ± 0.5 and 34.3 ± 0.3 µmole L-1 was respectively determined for the bisresorcinol and ursolic acid. The bisresorcinol was inhibitory to tyrosinase by exhibiting the IC50 of 22.8 µmole L-1, and that of 78.4 µmole L-1 was present for ß-arbutin. The bisresorcinol bound to collagenase, elastase, and tyrosinase with the respective binding energies of -5.89, -5.69, and -6.57 kcal mol-1. These binding energies were in the same ranges of tested inhibitors. The aromatic phenol groups in the structure were responsible for principle as well as supporting binding interactions with enzymes. Hydrogen binding due to hydroxyl groups and π-related attractive forces from an aromatic ring(s) provided binding versatility to bisresorcinol. CONCLUSION: The bisresorcinol purified from H. terminalis might be useful for inclusion in cosmetic products as an aging-enzyme antagonist.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32751614

RESUMO

Okra peel exhibits numerous therapeutic effects. This study explores the potential ameliorative effects of okra peel powder on high-fat-diet (HFD)-induced hypercholesterolemia and cognitive deficits. Thirty-six C57BL/6J male mice were randomly divided into six groups (n = 6 per group): (i) control, mice fed with a normal diet; (ii) HFD, mice fed with HFD; (iii) HFD-SIM, mice fed with HFD and given simvastatin (20 mg/kg/day); (iv) HFD-OP1; (v) HFD-OP2; (vi) HFD-OP3, mice fed with HFD and okra peel (200, 400, or 800 mg/kg/day, respectively). Following 10 weeks of treatments, the mice were subjected to the Morris water maze (MWM). Parameters such as weekly average body weight, food intake, and blood lipid profiles were also recorded. The HFD group showed a profound increase in total cholesterol and low-density lipoprotein concentration compared to the control group. All okra-treated and HFD-SIM groups performed better than the HFD group during acquisition trials, whereas only the HFD-OP1 produced a significantly higher number of entries into the platform zone during the probe trial. In sum, all three okra doses improved the learning ability of the mice. However, only the lowest dose of okra significantly improved the spatial reference memory retention.


Assuntos
Abelmoschus , Disfunção Cognitiva , Dieta Hiperlipídica , Extratos Vegetais , Animais , Peso Corporal , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/farmacologia
4.
Adv Med Sci ; 62(2): 266-272, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28501726

RESUMO

PURPOSE: Mesenchymal stem cells (MSCs) are multipotent adult stem cells and present in practically all tissues but originally identified within the bone marrow (BM). The differentiation potential of these cells is generally impaired when culturing in vitro for cell expansion. The aim of this study is to speedily increase the numbers of bone marrow derived mesenchymal stem cells (BM-MSCs) with substantially maintaining their differentiation potential in vitro and improving bone formation in vivo. MATERIALS AND METHODS: BM-MSCs isolated from rats were sequentially cultured in α-MEM containing basic fibroblast growth factor (FGF2) and/or insulin to stimulate proliferation and osteogenic commitment, and in the medium with the addition of bone morphogenetic protein 2 (BMP2) and/or bone morphogenetic protein 7 (BMP7) to arouse differentiation. The expression of genes markedly associating the commitment and differentiation were investigated in vitro using real-time PCR technique and mineralization assay, while the capacity of inducing bone formation by the established conditions was determined in vivo using a rat model. RESULTS: The BM-MSCs greatly proliferated with active transcription of runx2 and osterix genes when induced by FGF2 and insulin. The in vitro mineralization was enhanced by BMP2, but the extent was diminished when BMP2 was replaced or supplemented by BMP7. Formation of new small blood vessels was notably detected when the cells were respectively challenged by FGF2 plus insulin and BMP2. CONCLUSION: These data are valuable in choosing growth factors for proper bone repair. However, optimization of the established system would be essential when the cells of human source are applied.


Assuntos
Proteína Morfogenética Óssea 7/metabolismo , Diferenciação Celular , Fator 2 de Crescimento de Fibroblastos/metabolismo , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteogênese/fisiologia , Animais , Calcificação Fisiológica , Proliferação de Células , Células Cultivadas , Masculino , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/metabolismo , Ratos , Ratos Wistar
5.
Acta Pharm ; 66(3): 373-85, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27383886

RESUMO

Silicon-substituted calcium phosphate (Si-CaP) was developed in our laboratory as a biomaterial for delivery in bone tissue engineering. It was fabricated as a 3D-construct of scaffolds using chitosan-trisodium polyphosphate (TPP) cross-linked networks. In this study, heparin was covalently bonded to the residual -NH2 groups of chitosan on the scaffold applying carbodiimide chemistry. Bonded heparin was not leached away from scaffold surfaces upon vigorous washing or extended storage. Recombinant human bone morphogenetic protein 2 (rhBMP-2) was bound to conjugated scaffolds by ionic interactions between the negatively charged SO42- clusters of heparin and positively charged amino acids of rhBMP-2. The resulting scaffolds were inspected for bone regenerative capacity by subcutaneous implanting in rats. Histological observation and mineralization assay were performed after 4 weeks of implantation. Results from both in vitro and in vivo experiments suggest the potential of the developed scaffolds for bone tissue engineering applications in the future.


Assuntos
Anticoagulantes/administração & dosagem , Proteína Morfogenética Óssea 2/administração & dosagem , Regeneração Óssea/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Heparina/administração & dosagem , Alicerces Teciduais/química , Animais , Anticoagulantes/efeitos adversos , Anticoagulantes/química , Anticoagulantes/farmacologia , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 2/farmacologia , Fosfatos de Cálcio/efeitos adversos , Fosfatos de Cálcio/química , Quitosana/efeitos adversos , Quitosana/química , Quitosana/metabolismo , Materiais Revestidos Biocompatíveis/efeitos adversos , Reagentes de Ligações Cruzadas/química , Sistemas de Liberação de Medicamentos/efeitos adversos , Liberação Controlada de Fármacos , Etildimetilaminopropil Carbodi-Imida/química , Heparina/efeitos adversos , Heparina/química , Humanos , Masculino , Polifosfatos/efeitos adversos , Polifosfatos/química , Polifosfatos/metabolismo , Ratos Wistar , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Silicones/efeitos adversos , Silicones/química , Solubilidade , Propriedades de Superfície , Alicerces Teciduais/efeitos adversos
6.
J Pharm Sci ; 101(8): 2870-82, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22674208

RESUMO

In this study, a new generation of bioactive glass ceramics were developed using the wet chemical method. The synthetic conditions were strictly controlled to obtain the materials of a nanometric scale. As evaluated by scanning electron microscopy, bone-like apatite layers were produced in large amounts and completely covered their surfaces after immersion in phosphate buffer saline. On the basis of X-ray diffraction, X-ray fluorescence, and Fourier transform infrared spectroscopy results, PO4³â» groups of hydroxyapatite (HA) were partially substituted by SiO44⁻ species. The defective chemical structures introduced provided materials that were more biologically active, compared with the parent HA. For effective treatment of infected bones, scaffolds containing the bioactive ceramics were prepared by chitosan cross-linking, and loaded with vancomycin (VCM). The drug-loaded scaffolds were not toxic to bone cells. About 75%-80% of the entrapped drug was released in a controlled pattern and the release was sustained over a 12-day period. The concentration of drug released was determined to be above 20 times the half maximal effective concentration of VCM on Staphylococcus aureus, and was sufficient for killing bacteria growing as biofilm. In summary, the synthesized bioceramics exhibited many of properties associated with an ideal material for implantable drug delivery system, and were suitable for testing the ability to cure bone diseases including osteomyelitis.


Assuntos
Antibacterianos/administração & dosagem , Substitutos Ósseos/química , Cerâmica/química , Sistemas de Liberação de Medicamentos/métodos , Osteomielite/tratamento farmacológico , Vancomicina/administração & dosagem , Animais , Antibacterianos/farmacologia , Substitutos Ósseos/síntese química , Osso e Ossos/citologia , Linhagem Celular , Sobrevivência Celular , Cerâmica/síntese química , Durapatita/química , Humanos , Ratos , Dióxido de Silício/química , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Vancomicina/farmacologia
7.
Electron. j. biotechnol ; 14(5): 10-10, Sept. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640517

RESUMO

Lactic acid is a product that finds several applications in food, cosmetic, pharmaceutical and chemical industries. The main objective of this work is to evaluate potential use of the sap from palmyra (Borassus flabellifer Linn.) and oil palm (Elaeis guineensis) as substrate for lactic acid production by Lactobacillus casei TISTR 1500. The effects of acid hydrolysis, pH control and nutrient supplement of palmyra sap and oil palm sap on fermentation performance were investigated. It was found that lactic acid fermentation using palmyra sap was not significantly affected by either acid hydrolysis or pH control. The addition of MRS increased biomass and product yield. The final lactic acid concentration, dry cell weight and productivity were increased by increasing the total sugars of palmyra sap concentrations up to 134.0 g L-1. The kinetic parameters for the palmyra sap at 134.0 g L-1 total sugars were calculated to be of: specific growth rate (u) 0.05 h-1, the maximum productivity (R M) 2.02 g lactic acid L-1 h-1, cellular yield coefficient (Y X/S) 0.20 g cell g-1 sugar, and lactic acid yield (Y P/S) 0.78 g g-1. When oil palm sap was used as carbon source for L. casei TISTR 1500, pH control did not significantly affect lactic acid production. The addition of MRS medium into oil palm sap improved the biomass and the product yield for which the lactic acid production in static flask at 37ºC and pH 5.5 using 20 g L-1 of total sugars was improved to be of 0.55 g L-1 h-1. Oil palm sap could be served as a good potential source of raw materials for efficient production of lactic acid by L. casei TISTR 1500.


Assuntos
Arecaceae , Óleos de Plantas/metabolismo , Ácido Láctico/biossíntese , Lacticaseibacillus casei/metabolismo , Fermentação , Concentração de Íons de Hidrogênio
8.
FEMS Immunol Med Microbiol ; 48(1): 75-83, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16965354

RESUMO

Two strains of Lactobacillus crispatus (15L08 and 21L07) and one strain of Lactobacillus jensenii (5L08) were selected from amongst 100 isolates from the vaginas of healthy premenopausal women for properties relevant to mucosal colonization and the production of H2O2 and/or bacteriocin-like compound. All three strains self-aggregated and adhered to vaginal epithelial cells, displacing well-known vaginal pathogens, such as Gardnerella vaginalis and Candida albicans. Lactobacillus crispatus 15L08 was characterized as a potential H2O2 producer. A high level of bacteriocin-like compound was synthesized by L. jensenii 5L08, with a bactericidal mode of action for G. vaginalis, C. albicans and Escherichia coli. However, H2O2-dependent activity alone was not sufficient to inhibit the growth of C. albicans. Simultaneous actions of H2O2 and bacteriocin-like compound produced by lactobacilli may be important for antagonizing pathogenic bacteria. These strains of lactobacilli may be excellent candidates for eventual use as probiotics to restore the normal microbial communities in the vaginal ecosystem.


Assuntos
Antibiose/fisiologia , Lactobacillus/química , Probióticos/uso terapêutico , Vagina/microbiologia , Doenças Vaginais/terapia , Adulto , Anaerobiose , Aderência Bacteriana , Feminino , Humanos , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Lactobacillus/classificação , Pessoa de Meia-Idade , Probióticos/farmacologia , Vagina/efeitos dos fármacos
9.
Biochim Biophys Acta ; 1764(6): 1132-40, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16762606

RESUMO

To gain insight into how the N-terminal three-stranded beta-sheet-like domain in pediocin-like antimicrobial peptides positions itself on membranes, residues in the well-conserved (Y)YGNGV-motif in the domain were substituted and the effect of the substitutions on antimicrobial activity and binding of peptides to liposomes was determined. Peptide-liposome interactions were detected by measuring tryptophan-fluorescence upon exposing liposomes to peptides in which a tryptophan residue had been introduced in the N-terminal domain. The results revealed that the N-terminal domain associates readily with anionic liposomes, but not with neutral liposomes. The electrostatic interactions between peptides and liposomes facilitated the penetration of some of the peptide residues into the liposomes. Measuring the antimicrobial activity of the mutated peptides revealed that the Tyr2Leu and Tyr3Leu mutations resulted in about a 10-fold reduction in activity, whereas the Tyr2Trp, Tyr2Phe, Tyr3Trp and Tyr3Phe mutations were tolerated fairly well, especially the mutations in position 3. The Val7Ile mutation did not have a marked detrimental effect on the activity. The Gly6Ala mutation was highly detrimental, consistent with Gly6 being in one of the turns in the beta-sheet-like N-terminal domain, whereas the Gly4Ala mutation was tolerated fairly well. All mutations involving Asn5, including the conservative mutations Asn5Gln and Asn5Asp, were very deleterious. Thus, both the polar amide group on the side chain of Asn5 and its exact position in space were crucial for the peptides to be fully active. Taken together, the results are consistent with Val7 positioning itself in the hydrophobic core of target membranes, thus forcing most of the other residues in the N-terminal domain into the membrane interface region: Tyr3 and Asn5 in the lower half with their side chains pointing downward and approaching the hydrophobic core, Tyr2, Gly4 and His8 and 12 in the upper half, Lys1 near the middle of the interface region, and the side chain of Lys11 pointing out toward the membrane surface.


Assuntos
Bacteriocinas/química , Análise Mutacional de DNA , Acrilamida/química , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/química , Lipossomos/química , Lisina/química , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos
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