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1.
J Liposome Res ; 34(1): 18-30, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37144381

RESUMO

Small biospecific peptides with defined chemical structure and cellular responses are promising alternatives to full-length therapeutic proteins. Identification of these peptides solely or in combination with other bioactive factors and determination of their targets are of substantial interest in current drug delivery research. This study is aimed at the development of new liposomal formulations of ECM-derived GHK peptide known for its multiple regeneration-related activities but poorly recognized cellular targets. In situ association of membranotropic GHK derivative with unilamellar liposomes was performed to prepare GHK-modified liposomes with defined properties. According to DLS, the GHK component on the liposomal surface interacted with heparin in a specific manner compared to other polysaccharides and RGD counterpart, whereas ITC analysis of such interactions was complicated. The results provide a useful tool for screening of bio-interactions of synthetic peptide-presenting liposomes by the DLS technique. They were also employed to produce a multi-functional nanosized GHK-heparin covering for liposomes. The resulting composite liposomes possessed low size dispersity, increased anionic charge, and mechanical rigidity. The heparin component significantly promoted the accumulation of GHK-modified liposomes in 3T3 fibroblasts so that the composite liposomes exhibited the highest cell-penetrating activity. Furthermore, the latter formulation stimulated cell proliferation and strongly inhibited ROS production and GSH depletion under oxidative stress conditions. Together, the results support that cell-surface glycosaminoglycans can be involved in GHK-mediated liposomal delivery, which can be further greatly enhanced by association with heparin. The composite liposomes with GHK-heparin covering can be considered as an advanced GHK-based formulation for therapeutic and cosmeceutical applications.


Assuntos
Heparina , Lipossomos , Lipossomos/química , Peptídeos/química , Sistemas de Liberação de Medicamentos , Lipossomas Unilamelares , Proliferação de Células
2.
J Nat Prod ; 86(8): 1939-1949, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37497692

RESUMO

A convenient synthesis is presented for a new class of bioactive bifunctionalized conjugates of lupane-type triterpenoids with triphenylphosphonium (TPP) and glycopyranosyl targeting moieties. The main synthesis steps include glycosylation of haloalkyl esters of the triterpene acid at the C-3 position by the imidate derivatives of glycopyranose followed by the product modification at the C-28 position with triphenylphosphine. The conjugates of betulinic acid (BetA) with TPP and d-glucose, l-rhamnose, or d-mannose moieties were thus synthesized as potential next-generation BetA-derived anticancer compounds. LC-MS/MS analysis in glucose-free physiological solution indicated that the glycosides showed better accumulation in PC-3 prostate cancer cells than both BetA and TPP-BetA conjugate, while the transporting effect of monosaccharide residues increased as follows: d-mannose < l-rhamnose ≈ d-glucose. At saturated concentrations, the glycosides caused a disturbing effect on mitochondria with a more drastic drop in transmembrane potential but weaker overproduction of mitochondrial reactive oxygen species (ROS) compared to TPP-BetA conjugate. Cytotoxicity of the glycosides in culture medium was comparable with or higher than that of the nonglycosylated conjugate, depending on the cancer cell line, whereas the compounds were less active toward primary fibroblasts. Glycosylation tended to increase pro-apoptotic and decrease pro-autophagic activities of the BetA derivatives. Cytotoxicity of the synthesized glycosides was considered in comparison with the summarized data on the natural and modified BetA glycosides. The results obtained are important for the development of bifunctionalized conjugates of triterpenoids with an increased cancer cell targetability.


Assuntos
Neoplasias , Triterpenos , Masculino , Humanos , Ácido Betulínico , Manose , Cromatografia Líquida , Ramnose , Espectrometria de Massas em Tandem , Triterpenos/farmacologia , Triterpenos/química , Glicosídeos
3.
Int J Mol Sci ; 24(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37446245

RESUMO

Considering the important cytoprotective and signaling roles but relatively narrow therapeutic index of hydrogen sulfide (H2S), advanced H2S donors are required to achieve a therapeutic effect. In this study, we proposed glutathione dithiophosphates as new combination donors of H2S and glutathione. The kinetics of H2S formation in dithiophosphate solutions suggested a continuous H2S release by the donors, which was higher for the dithiophosphate of reduced glutathione than oxidized glutathione. The compounds, unlike NaHS, inhibited the proliferation of C2C12 myoblasts at submillimolar concentrations due to an efficient increase in intracellular H2S. The H2S donors more profoundly affected reactive oxygen species and reduced glutathione levels in C2C12 myocytes, in which these parameters were elevated compared to myoblasts. Oxidized glutathione dithiophosphate as well as control donors exerted antioxidant action toward myocytes, whereas the effect of reduced glutathione dithiophosphate at (sub-)micromolar concentrations was rather modulating. This dithiophosphate showed an enhanced negative inotropic effect mediated by H2S upon contraction of the atrial myocardium, furthermore, its activity was prolonged and reluctant for washing. These findings identify glutathione dithiophosphates as redox-modulating H2S donors with long-acting profile, which are of interest for further pharmacological investigation.


Assuntos
Sulfeto de Hidrogênio , Dissulfeto de Glutationa , Sulfeto de Hidrogênio/farmacologia , Glutationa/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Oxirredução
4.
Exp Brain Res ; 239(2): 627-638, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33388811

RESUMO

Localized carrier-mediated administration of drugs is a promising approach to treatment of acute phase of spinal cord injury (SCI) as it allows enhanced and/or sustained drug delivery to damaged tissues along with minimization of systemic side effects. We studied the effect of locally applied self-assembling micellar formulation of methylprednisolone succinate (MPS) with trifunctional block copolymer of ethylene oxide and propylene oxide (TBC) on functional recovery and tissue drug content after SCI in rats in comparison with local and systemic administration of MPS alone. Variations in the amplitude of motor evoked responses in the hindlimb muscles induced by epidural stimulation during acute phase of SCI and restoration of movements during chronic period after local vs. systemic application of MPS were evaluated in this study. Results demonstrate that local delivery of MPS in combination with TBC facilitates spinal cord sensorimotor circuitry, increasing the excitability. In addition, this formulation was found to be more effective in improvement of locomotion after SCI compared to systemic administration. LC-MS/MS data shows that the use of TBC carrier increases the glucocorticoid content in treated spinal cord by more than four times over other modes of treatment. The results of this study demonstrate that the local treatment of acute SCI with MPS in the form of mixed micelles with TBC can provide improved therapeutic outcome by promoting drug accumulation and functional restoration of the spinal cord.


Assuntos
Hemissuccinato de Metilprednisolona , Traumatismos da Medula Espinal , Animais , Cromatografia Líquida , Ratos , Medula Espinal , Traumatismos da Medula Espinal/tratamento farmacológico , Espectrometria de Massas em Tandem
5.
Molecules ; 26(10)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067789

RESUMO

Phosphorus species are potent modulators of physicochemical and bioactive properties of peptide compounds. O,O-diorganyl dithiophoshoric acids (DTP) form bioactive salts with nitrogen-containing biomolecules; however, their potential as a peptide modifier is poorly known. We synthesized amphiphilic ammonium salts of O,O-dimenthyl DTP with glutathione, a vital tripeptide with antioxidant, protective and regulatory functions. DTP moiety imparted radical scavenging activity to oxidized glutathione (GSSG), modulated the activity of reduced glutathione (GSH) and profoundly improved adsorption and electrooxidation of both glutathione salts on graphene oxide modified electrode. According to NMR spectroscopy and GC-MS, the dithiophosphates persisted against immediate dissociation in an aqueous solution accompanied by hydrolysis of DTP moiety into phosphoric acid, menthol and hydrogen sulfide as well as in situ thiol-disulfide conversions in peptide moieties due to the oxidation of GSH and reduction of GSSG. The thiol content available in dissolved GSH dithiophosphate was more stable during air oxidation compared with free GSH. GSH and the dithiophosphates, unlike DTP, caused a thiol-dependent reduction of MTS tetrazolium salt. The results for the first time suggest O,O-dimenthyl DTP as a redox modifier for glutathione, which releases hydrogen sulfide and induces biorelevant redox conversions of thiol/disulfide groups.


Assuntos
Glutationa/química , Fosfatos/química , Antioxidantes , Dissulfetos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo , Fosfatos/metabolismo , Compostos de Sulfidrila
6.
Eur Biophys J ; 48(1): 25-34, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30105402

RESUMO

Chemical modification of therapeutic peptides is an important approach to improving their physicochemical and pharmacokinetic properties. The triphenylphosphonium (TPP) cation has proved to be a powerful modifier; however, its effects on peptide structure and activity remain uncharacterized. In this study, cytoprotective tetrapeptides based on the YRFK opioid motif with L- or D-Arg residues were linked to (triphenylphosphonio)carboxylic acids with ethylene and pentylene spacers (TPP-3 and TPP-6 groups, respectively). The three-dimensional structure of the oligopeptides was analyzed by NMR spectroscopy, computational methods and circular dichroism (CD). A more compact and bent structure with segregated aromatic groups was revealed for the D-arginine-containing tetrapeptide and its TPP-6 derivative. The TPP moiety caused structure-organizing effect on the tetrapeptides, resulting in transition from random coil to ß-sheet structures, and decreased the peptide backbone flexibility up to ten times. The TPP-3-modified oligopeptide with the lowest RMSD value (ca. 0.05 Å) was characterized by intrapeptide hydrophobic interactions between the TPP and side groups of Tyr and Phe residues accompanied by strong CD induction. The TPP-6-modified oligopeptides showed enhanced ability to form intermolecular associates and disturb liposomal membranes. The relationship between the spatial structure of the oligopeptides and some of their biologically relevant interactions were additionally revealed and are discussed.


Assuntos
Oligopeptídeos/química , Compostos Organofosforados/química , Motivos de Aminoácidos , Sequência de Aminoácidos , Modelos Moleculares , Estereoisomerismo
7.
Bioorg Med Chem ; 27(1): 100-109, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30503413

RESUMO

The pyridine-derived biomolecules are of considerable interest in developing medicinal compounds with various specific activities. Novel ammonium salts of pyridoxine, (S)-(-)-nicotine and nicotinamide with O,O-diorganyl dithiophosphoric acids (DTPA) were synthesized and characterized. The complexation of chiral monoterpenyl DTPA, including (S)-(-)-menthyl, (R)-(+)-menthyl, (1R)-endo-(+)-fenchyl, (1S,2S,3S,5R)-(+)-isopinocampheolyl derivatives, with pyridoxine and nicotine provided effective antibacterial compounds 3a,b,e,f, and 5a,b,d,f with MIC values against Gram-positive bacteria as low as 10 µM (6 µg/mL). Two selected pyridoxine and nicotine salts based on menthyl DTPA 3a and 5a were similarly active against antibiotic-resistant bacteria from burn wounds including MRSA. The compounds had enhanced amphiphilic and hemolytic properties and effectively altered surface characteristics and matrix-secreting ability of P. aeroginosa and S. aureus. MBC/MIC ratios of 3a and 5a suggested the bactericidal mode of their action. Furthermore, the compounds exhibited moderate cytotoxicity towards human skin fibroblasts (IC50 = 48.6 and 57.6 µM, respectively, 72 h), encouraging their further investigation as potential antimicrobials against skin and wound infections.


Assuntos
Antibacterianos/farmacologia , Niacinamida/farmacologia , Nicotina/farmacologia , Fosfatos/farmacologia , Piridoxina/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/toxicidade , Fibroblastos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Niacinamida/síntese química , Niacinamida/química , Niacinamida/toxicidade , Nicotina/síntese química , Nicotina/química , Nicotina/toxicidade , Fosfatos/síntese química , Fosfatos/química , Fosfatos/toxicidade , Piridoxina/síntese química , Piridoxina/química , Piridoxina/toxicidade , Staphylococcus epidermidis/efeitos dos fármacos
8.
J Nat Prod ; 80(8): 2232-2239, 2017 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-28782948

RESUMO

A series of new triphenylphosphonium (TPP) derivatives of the triterpenoid betulin (1, 3-lup-20(29)-ene-3ß,28-diol) have been synthesized and evaluated for cytotoxic effects against human breast cancer (MCF-7), prostate adenocarcinoma (PC-3), vinblastine-resistant human breast cancer (MCF-7/Vinb), and human skin fibroblast (HSF) cells. The TPP moiety was applied as a carrier group through the acyl linker at the 28- or 3- and 28-positions of betulin to promote cellular and mitochondrial accumulation of the resultant compounds. A structure-activity relationship study has revealed the essential role of the TPP group in the biological properties of the betulin derivatives produced. The present results showed that a conjugate of betulin with TPP (3) enhanced antiproliferative activity toward vinblastine-resistant MCF-7 cells, with an IC50 value as low as 0.045 µM.


Assuntos
Mitocôndrias/química , Compostos Organofosforados/síntese química , Compostos Organofosforados/farmacologia , Triterpenos/síntese química , Triterpenos/farmacologia , Neoplasias da Mama , Linhagem Celular Tumoral , Desenho de Fármacos , Humanos , Concentração Inibidora 50 , Células MCF-7 , Estrutura Molecular , Compostos Organofosforados/química , Compostos Organofosforados/isolamento & purificação , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação
9.
J Pharm Sci ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38508340

RESUMO

Vitamin K derivatives such as menadione (MD) have been recognized as promising redox-modulating and chemosensitizing agents for anticancer therapy, however, their cellular activities in peptide-targeted nanocarriers have not been elucidated to date. This study provides the guidelines for developing MD-loaded solid lipid nanoparticles (SLN) modified with extracellular matrix (ECM)-derived peptides. Relationships between RGD peptide concentration and changes in DLS characteristics as well as accumulation of SLN in cancer cells were revealed to adjust the peptide-lipid ratio. SLN system maintained adequate nanoparticle concentration and low dispersity after introduction of MD and MD/RGD, whereas formulated MD was protected from immediate conjugation with reduced glutathione (GSH). RGD-modified MD-containing SLN showed enhanced prooxidant, GSH-depleting and cytotoxic activities toward PC-3 prostate cancer cells attributed to improved cellular pharmacokinetics of the targeted formulation. Furthermore, this formulation effectively sensitized PC-3 cells and OVCAR-4 ovarian cancer cells to free doxorubicin and cisplatin so that cell growth was inhibited by MD-drug composition at nontoxic concentrations of the ingredients. These results provide an important background for further improving chemotherapeutic methods based on combination of conventional cytostatics with peptide-targeted SLN formulations of MD.

10.
Bioorg Med Chem ; 21(14): 4388-95, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23683836

RESUMO

A series of 13 phosphonium salts on the basis of pyridoxine derivatives were synthesized and their antibacterial activity against clinically relevant strains was tested in vitro. All compounds were almost inactive against gram-negative bacteria and exhibited structure-dependent activity against gram-positive bacteria. A crucial role of ketal protection group in phosphonium salts for their antibacterial properties was demonstrated. Among synthesized compounds 5,6-bis[triphenylphosphonio(methyl)]-2,2,8-trimethyl-4H-[1,3]dioxino[4,5-c]pyridine dichloride (compound 20) was found to be the most effective towards Staphylococcus aureus and Staphylococcus epidermidis strains (MIC 5µg/ml). The mechanism of antibacterial activity of this compound probably involves cell penetration and interaction with genomic and plasmid DNA.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Compostos Organofosforados/síntese química , Compostos Organofosforados/farmacologia , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Humanos , Estrutura Molecular , Compostos Organofosforados/química , Piridoxina/síntese química , Piridoxina/química , Piridoxina/farmacologia , Pele/efeitos dos fármacos
11.
Gels ; 9(2)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36826275

RESUMO

Synthetic hydrogels provide a promising platform to produce neural tissue analogs with improved control over structural, physical, and chemical properties. In this study, oligo (poly (ethylene glycol) fumarate) (OPF)-based macroporous cryogels were developed as a potential next-generation alternative to a non-porous OPF hydrogel previously proposed as an advanced biodegradable scaffold for spinal cord repair. A series of OPF cryogel conduits in combination with PEG diacrylate and 2-(methacryloyloxy) ethyl-trimethylammonium chloride (MAETAC) cationic monomers were synthesized and characterized. The contribution of each component to viscoelastic and hydration behaviors and porous structure was identified, and concentration relationships for these properties were revealed. The rheological properties of the materials corresponded to those of neural tissues and scaffolds, according to the reviewed data. A comparative assessment of adhesion, migration, and proliferation of neuronal cells in multicomponent cryogels was carried out to optimize cell-supporting characteristics. The results show that OPF-based cryogels can be used as a tunable synthetic scaffold for neural tissue repair with advantages over their hydrogel counterparts.

12.
Biomater Adv ; 153: 213538, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37390562

RESUMO

Antibiotic loaded bone cements are widely used in total joint replacement (TJR); despite many limitations such as a burst release which leads to antibiotic concentration below inhibitory levels and possibly contributing to the selection of antibiotic resistant strains. In order to address such limitations and to simultaneously address antibiotic resistance and short-term antimicrobial activity, we developed a nanocomposite bone cement capable of providing a controlled release of antimicrobial agents from bone cement to act as prophylaxis or treatment against prosthetic joint infections (PJIs). Gentamicin and chlorhexidine were loaded in combination on silica nanoparticles surface using layer-by-layer coating technique (LbL) combining hydrolysable and non-hydrolysable polymers. The drug release from the nanocomposite continued for >50 days at concentrations higher than the commercial formulation containing the same amount of antimicrobial drugs, where burst release for few days were observed. Moreover, the nanocomposite bone cement showed superior antimicrobial inhibition without adversely affecting the mechanical properties or the ability of osteoblasts to grow. In vivo experiments with an infected bone lesion model along with mass-spectrometric analysis also provided further evidence of efficacy and safety of the implanted nanocomposite material as well as its prolonged drug eluting profile. The developed nanocomposite bone cement has the potential to reduce PJIs and enable treatment of resistant established infections; moreover, the newly developed LbL based nano-delivery system may also have wider applications in reducing the threat posed by antimicrobial resistance.


Assuntos
Cimentos Ósseos , Nanocompostos , Nanopartículas , Nanocompostos/química , Cimentos Ósseos/química , Antibacterianos/química , Antibacterianos/farmacologia , Humanos , Animais , Ratos , Ratos Wistar , Linhagem Celular Tumoral , Nanopartículas/química , Gentamicinas/farmacologia , Ortopedia
13.
Micromachines (Basel) ; 14(4)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37421116

RESUMO

Synthetic peptides are promising structural and functional components of bioactive and tissue-engineering scaffolds. Here, we demonstrate the design of self-assembling nanofiber scaffolds based on peptide amphiphile (PA) molecules containing multi-functional histidine residues with trace metal (TM) coordination ability. The self-assembly of PAs and characteristics of PA nanofiber scaffolds along with their interaction with Zn, Cu, and Mn essential microelements were studied. The effects of TM-activated PA scaffolds on mammalian cell behavior, reactive oxygen species (ROS), and glutathione levels were shown. The study reveals the ability of these scaffolds to modulate adhesion, proliferation, and morphological differentiation of neuronal PC-12 cells, suggesting a particular role of Mn(II) in cell-matrix interaction and neuritogenesis. The results provide a proof-of-concept for the development of histidine-functionalized peptide nanofiber scaffolds activated with ROS- and cell-modulating TMs to induce regenerative responses.

14.
Artigo em Inglês | MEDLINE | ID: mdl-36593927

RESUMO

We study for the first time whether triphenylphosphonium (TPP) moiety can improve cellular delivery and redox properties of amphipathic cationic peptides based on YRFK/YrFK cell-penetrating and cytoprotective motif. TPP moiety was found to increase reducing activity of both stereoisomeric peptides in solution and on electrode surface in association with TPP-mediated intramolecular interactions. Among TPP-conjugated peptides, newly synthesized TPP3-YrFK featured both increased antioxidant efficacy and proteolytic resistance. TPP-conjugated peptides preferably mitigated endogenic ROS in mitochondria and cytoplasm of model glioblastoma cells with increased oxidative status. This anti-ROS effect was accompanied by mild reversible decrease of reduced glutathione level in the cells with relatively weak change in glutathione redox forms ratio. Such low interference with cell redox status is in accordance with non-cytotoxic nature of the compounds. Intracellular concentrations of label-free peptides were analyzed by LC-MS/MS, which showed substantial TPP-promoted penetration of YrFK motif across cell plasma membrane. However, according to ΔΨm analysis, TPP moiety did not profoundly enhance peptide interaction with mitochondrial inner membrane. Our study clarifies the role of TPP moiety in cellular delivery of amphipathic cationic oligopeptides. The results suggest TPP moiety as a multi-functional modifier for the oligopeptides which is capable of improving cellular pharmacokinetics and antioxidant activity as well as targeting increased ROS levels. The results encourage further investigation of TPP3-YrFK as a peptide antioxidant with multiple benefits.

15.
Antioxidants (Basel) ; 11(2)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35204274

RESUMO

Thiol compounds including predominantly glutathione (GSH) are key components of redox homeostasis, which are involved in the protection and regulation of mammalian cells. The assessment of cell redox status by means of in situ analysis of GSH in living cells is often preferable over established assays in cell lysates due to fluctuations of the GSH pool. For this purpose, we propose a microplate assay with monochlorobimane (MCB) as an available fluorescent probe for GSH, although poorly detected in the microplate format. In addition to the new procedure for improved MCB-assisted GSH detection in plate-grown cells and its verification with GSH modulators, this study provides a useful methodology for the evaluation of cell redox status probed through relative GSH content and responsiveness to both supplemented thiols and variation in oxygen pressure. The roles of extracellular interactions of thiols and natural variability of cellular glutathione on the assay performance were emphasized and discussed. The results are of broad interest in cell biology research and should be particularly useful for the characterization of pathological cells with decreased GSH status and increased oxidative status as well as redox-modulating factors.

16.
Gels ; 8(2)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35200498

RESUMO

Divalent trace metals (TM), especially copper (Cu), cobalt (Co) and zinc (Zn), are recognized as essential microelements for tissue homeostasis and regeneration. To achieve a balance between therapeutic activity and safety of administered TMs, effective gel formulations of TMs with elucidated regenerative mechanisms are required. We studied in vitro and in vivo effects of biodegradable macroporous cryogels doped with Cu, Co or Zn in a controllable manner. The extracellular ROS generation by metal dopants was assessed and compared with the intracellular effect of soluble TMs. The stimulating ability of TMs in the cryogels for cell proliferation, differentiation and cytokine/growth factor biosynthesis was characterized using HSF and HUVEC primary human cells. Multiple responses of host tissues to the TM-doped cryogels upon subcutaneous implantation were characterized taking into account the rate of biodegradation, production of HIF-1α/matrix metalloproteinases and the appearance of immune cells. Cu and Zn dopants did not disturb the intact skin organization while inducing specific stimulating effects on different skin structures, including vasculature, whereas Co dopant caused a significant reorganization of skin layers, the appearance of multinucleated giant cells, along with intense angiogenesis in the dermis. The results specify and compare the prooxidant and regenerative potential of Cu, Co and Zn-doped biodegradable cryogels and are of particular interest for the development of advanced bioinductive hydrogel materials for controlling angiogenesis and soft tissue growth.

17.
Anal Bioanal Chem ; 401(8): 2591-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21892642

RESUMO

We designed an electrochemical sensor based on a carbon nanotube modified electrode (ME) to analyze DNA-cleaving activity. The cleavage of high molecular weight DNA resulted in an increase in the oxidation current from DNA guanine nucleotides due to a change in DNA adsorptive behavior on the surface of the ME. DNA digestion with DNAse I was accompanied by a linear increase in the DNA signal in proportion to the enzyme activity. We then proposed an assay based on the sensor for the direct assessment of the total deoxyribonuclease activity of blood serum as well as the separate detection of DNAse I and DNA abzymes. The assay was applied to analyze deoxyribonucleases in sera from 21 healthy donors and 17 patients with autoimmune thyroiditis. Our results show that the response of the sensor to DNA cleavage by blood deoxyribonucleases is a promising diagnostic criterion for autoimmune thyroiditis. This sensor can be implemented in a disposable screen-printed electrode format for application in clinical laboratories.


Assuntos
Técnicas Biossensoriais/métodos , Desoxirribonucleases/sangue , Técnicas Eletroquímicas/métodos , Tireoidite Autoimune/sangue , Tireoidite Autoimune/enzimologia , Adulto , DNA/metabolismo , Desoxirribonuclease I/metabolismo , Eletrodos , Feminino , Humanos , Pessoa de Meia-Idade , Nanotubos de Carbono/química , Oxirredução , Tireoidite Autoimune/diagnóstico
18.
Mater Sci Eng C Mater Biol Appl ; 120: 111660, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33545827

RESUMO

Synthetic oligopeptides are a promising alternative to natural full-length growth factors and extracellular matrix (ECM) proteins in tissue regeneration and therapeutic angiogenesis applications. In this work, angiogenic properties of dual and triple compositions containing RGD, GHK peptides and copper (II) ions (Cu2+) were for the first time studied. To reveal specific in vitro effects of these compositions in three-dimensional scaffold, adamantyl group bearing peptides, namely Ada-Ahx-GGRGD (1) and Ada-Ahx-GGGHK (2), were effectively immobilized in bioinert pHEMA macroporous cryogel via host-guest ß-cyclodextrin-adamantane interaction. The cryogels were additionally functionalized with Cu2+ via the formation of GHK-Cu complex. Angiogenic responses of HUVECs grown within the cryogel ECM model were analyzed. The results demonstrate that the combination of RGD with GHK and further with Cu2+ dramatically increases cell proliferation, differentiation, and production of a series of angiogenesis related cytokines and growth factors. Furthermore, the level of glutathione, a key cellular antioxidant and redox regulator, was altered in relation to the angiogenic effects. These results are of particular interest for establishing the role of multiple peptide signals on regeneration related processes and for developing improved tissue engineering materials.


Assuntos
Cobre , Criogéis , Oligopeptídeos/farmacologia , Peptídeos , Cicatrização
19.
Langmuir ; 26(7): 5153-9, 2010 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-20350012

RESUMO

The composite silver and gold nanoparticles (AgNPs and AuNPs) coated with nonionic amphiphilic block copolymers (Pluronics L121, F68, or F127) are prepared by their adsorption under critical micelle concentrations. It is found that Pluronics bind to the surface of metal NPs as a very thin film by the hydrophobic association through poly(propylene oxide) block of the copolymers. The modification increases the colloidal stability of NPs with increasing hydrophilic-lipophilic balance of Pluronics in the order of L121, F127, and F68. In order to investigate the potentials of polymer coated noble metal NPs as surface-enhanced Raman spectroscopy (SERS) probes, fluorescent dyes and doxorubicin are used as model compounds. It is found that Pluronic component promotes the adsorption of these compounds on the composite NPs resulting in a considerable increase of Raman signal. This effect is attributed to increased concentration of the analyte molecules on the composite surface due to the hydrophobic and charge-charge interactions between the analytes and the Pluronic coat, and the stabilization of NPs by poly(ethylene oxide) blocks. The copolymer coated AgNPs show higher SERS activity than the counterparts prepared with AuNPs. Among the prepared composites, the AgNPs modified with Pluronic F127 containing extended poly(propylene oxide) and poly(ethylene oxide) blocks exhibit maximal Raman activity using rhodamine 6G (Rh6G) with a EF of 9.04 x 10(6). The results show that the developed Pluronic-based SERS probes can be used for sensitive and selective analysis of organic analytes.


Assuntos
Nanopartículas Metálicas/química , Micelas , Poloxâmero/química , Análise Espectral Raman/métodos , Adsorção , Ouro/química , Interações Hidrofóbicas e Hidrofílicas , Polietilenoglicóis/química , Polímeros/química
20.
ACS Appl Bio Mater ; 3(2): 1116-1128, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35019313

RESUMO

Oligopeptides are versatile cell modulators resembling pleiotropic activities of ECM proteins and growth factors. Studying the role of cell-instructive peptide signals within 3D scaffolds, yet poorly known, requires effective approaches to introducing bioactive sequences into appropriate materials. We synthesized RGD and GHK motif based peptides 1 and 2 linked to the terminal adamantyl group (Ad) and their fluorescent derivatives 3 and 4. Poly(hydroxyethyl methacrylate) (pHEMA) cryogels with additional PEG/ß-cyclodextrin (CD) units were prepared as an inert macroporous scaffold capable to bind the adamantylated peptides via affinity CD-Ad complexation. According to toluidine blue staining, the CD moieties were effectively and stably incorporated in the pHEMA cryogels at nanomolar amounts per milligram of material. The CD component gradually increased the thickness and swelling ability of the polymer walls of cryogels, resulting in a noticeable decrease in macropore size and modulation of viscoelastic properties. The labeled peptides exhibited fast kinetics of specific binding to the CD-modified cryogels and were simultaneously immobilized by coincubation. The peptide loading approached ca. 0.31 mg per cm2 of cryogel sheet. A well-defined mitogenic effect of the immobilized peptides (2 < 1≪ 1 + 2) was revealed toward 3T3 and PC-12 cells. The synergistic action of RGD and GHK peptides induced a profound change in cell behavior/morphology attributed to a growth-factor-like activity of the composition. Altogether, our results provide an effective procedure for the preparation of CD-modified pHEMA cryogels and their uniform in situ functionalization with bioactive peptide(s) of interest and an informative study of cellular responses in the functionalized scaffolds.

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