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ACS Applied Materials & Interfaces May 2022An imperative processing way to produce 3D printed structures with enhanced multifunctional properties is printing inks in the form of a gel-like colloidal emulsion. The...
An imperative processing way to produce 3D printed structures with enhanced multifunctional properties is printing inks in the form of a gel-like colloidal emulsion. The surface-modified microcrystalline cellulose (MCC) is an excipient of outstanding merit as a particulate emulsifier to manufacture a stable Pickering emulsion gel. The tuning of the MCC structure by cationic antimicrobial compounds, such as ε-polylysine (ε-PL), can offer a surface activity with an antimicrobial effect. However, the MCC/ε-PL lacks the appropriate emulsifying ability due to the development of electrostatic complexes. To overcome this challenge, (i) a surface-active MCC conjugate was synthesized by a sustainable dual-grafting technique (ii) to produce a highly stable therapeutic soy-based Pickering emulsion gel (iii) for potential application in 3D printing. In this regard, the tea polyphenols were initially introduced into MCC by the free-radical grafting method to decrease the charge density of anionic MCC. Then, the antioxidative MCC--tea polyphenols were reacted by ε-PL to produce a dual-grafted therapeutic MCC conjugate (micro-biosurfactant), stabilizing the soy-based emulsion system. The results indicated that the dual-grafted micro-biosurfactant formed a viscoelastic and thixotropic soy-based emulsion gel with reduced droplet size and long-term stability. Besides, there was an improvement in the interfacial adsorption features of soy-protein particles after micro-biosurfactant incorporation, where the interfacial pressure and surface dilatational viscoelastic moduli were enhanced. Consequently, it was revealed that the therapeutic Pickering emulsion gel was more suitable to manufacture a well-defined 3D architecture with high resolution and retained permanent deformation after unloading (i.e., a recoverable matrix). This work established that the modification of the MCC backbone by tea polyphenols and ε-PL advances its bioactive properties and emulsifying performance, which finally obtains a soy-based 3D printed structure with noteworthy mechanical strength.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Cations; Cellulose; Emulsions; Polylysine; Polyphenols; Printing, Three-Dimensional; Tea
PubMed: 35476424
DOI: 10.1021/acsami.1c19430 -
FEBS Letters Feb 2003Extracellular matrix (ECM) of tissues, vascular tissue in particular, contains a high concentration of negatively charged glycosaminoglycans (GAGs), which are involved...
Extracellular matrix (ECM) of tissues, vascular tissue in particular, contains a high concentration of negatively charged glycosaminoglycans (GAGs), which are involved in the regulation of cell motility, cell proliferation and the regulation of enzyme activities. Previously, we have shown that the vascular ECM is capable of binding an extremely high concentration of positively charged molecules, such as polylysine. Vascular ECM can be used therefore as a substrate for binding and retention of drugs delivered intravascularly, if these drugs are endowed with an ability to bind to the vascular ECM. In this study, we evaluated a number of positively charged molecules as potential affinity vehicles for delivery of drugs to the vascular ECM. We labelled the molecules of interest with fluorescence and compared them ex vivo in terms of binding and retention in the de-endothelialised rat carotid artery after intravascular delivery under pressure. High molecular weight polylysine (84 kDa) and polyamidoamine (PAMAM) dendrimers accumulated in the wall of the artery up to a concentration of 10 mg/ml and were not washed away significantly after 4 h of perfusion of the artery. A 24-mer peptide containing a consensus sequence for binding to GAGs (ARRRAARA)(3), 2.7 kDa, was comparable to high molecular weight polylysine and dendrimers in terms of binding and retention. A 14-mer GAG-binding peptide from vitronectin and low molecular weight polylysine, 3 kDa, accumulated in the vascular wall up to about 3 mg/ml and was washed away after 30 min of perfusion. A 10-mer consensus GAG-binding peptide did not bind significantly to the vascular tissue. We conclude that the consensus 24-mer GAG-binding peptide is by far superior to polylysine of a similar molecular weight in terms of binding to vascular tissue, and can provide high accumulation and long-term retention of a low molecular weight compound (fluorescein, as a model molecule) in the vascular wall. Rationally designed GAG-binding peptides can be useful as affinity vehicles for targeting drugs to the vascular ECM.
Topics: Amino Acid Sequence; Animals; Biological Transport; Carotid Arteries; Fluorescent Dyes; In Vitro Techniques; Kinetics; Muscle, Smooth, Vascular; Oligopeptides; Polylysine; Rats
PubMed: 12606022
DOI: 10.1016/s0014-5793(03)00063-2 -
Biophysical Journal Oct 2009Complexes formed from DNA and polycations are of interest because of their potential use in gene therapy; however, there remains a lack of understanding of the structure...
Complexes formed from DNA and polycations are of interest because of their potential use in gene therapy; however, there remains a lack of understanding of the structure and formation of DNA-polycation complexes at atomic scale. In this work, molecular dynamics simulations of the DNA duplex d(CGCGAATTCGCG) in the presence of polycation chains are carried out to shed light on the specific atomic interaction that result in complex formation. The structures of complexes formed from DNA with polyethylenimine, which is considered one of the most promising DNA vector candidates, and a second polycation, poly-L-lysine, are compared. After an initial separation of approximately 50 A, the DNA and polycation come together and form a stable complex within 10 ns. The DNA does not undergo any major structural changes on complexation and remains in the B-form. In the formed complex, the charged amine groups of the polycation mainly interact with DNA phosphate groups, with polycation intrusion into the major and minor grooves dependent on the identity and charge state of the polycation. The ability of the polycation to effectively neutralize the charge of the DNA phosphate groups and the resulting influence on the DNA helix interaction are discussed.
Topics: Base Sequence; Cations; DNA; Molecular Dynamics Simulation; Nucleic Acid Conformation; Polyethyleneimine; Polylysine; Substrate Specificity; Water
PubMed: 19804728
DOI: 10.1016/j.bpj.2009.03.069 -
International Journal of Molecular... Feb 2023is a major hospital-associated pathogen that can cause severe infections, most notably in patients with cystic fibrosis (CF) or those hospitalized in intensive care...
is a major hospital-associated pathogen that can cause severe infections, most notably in patients with cystic fibrosis (CF) or those hospitalized in intensive care units. Given its remarkable ability to resist antibiotics, eradication has grown more challenging. Therefore, there is an urgent need to discover and develop new strategies that can counteract -resistant strains. Here, we evaluated the efficacy of poly-L-lysine (pLK) in combination with commonly used antibiotics as an alternative treatment option against . First, we demonstrated by scanning electron microscopy that pLK alters the integrity of the surface membrane of . We also showed using a fluorometry test that this results in an enhanced permeability of the bacteria membrane. Based on these data, we further evaluated the effect of the combinations of pLK with imipenem, ceftazidime, or aztreonam using the broth microdilution method in vitro. We found synergies in terms of bactericidal effects against either sensitive or resistant strains, with a reduction in bacterial growth (up to 5-log compared to the control). Similarly, these synergistic and bactericidal effects were confirmed ex vivo using a 3D model of human primary bronchial epithelial cells maintained in an air-liquid interface. In conclusion, pLK could be an innovative antipseudomonal molecule, opening its application as an adjuvant antibiotherapy against drug-resistant strains.
Topics: Humans; Pseudomonas aeruginosa; Polylysine; Pseudomonas Infections; Microbial Sensitivity Tests; Anti-Bacterial Agents
PubMed: 36769174
DOI: 10.3390/ijms24032851 -
The Journal of Antibiotics Nov 1984The antimicrobial spectrum of epsilon-poly-L-lysine (n = 25-30, epsilon-PL) was investigated by comparison with alpha-poly-L-lysine (n = 50, alpha-PL). epsilon-PL showed...
The antimicrobial spectrum of epsilon-poly-L-lysine (n = 25-30, epsilon-PL) was investigated by comparison with alpha-poly-L-lysine (n = 50, alpha-PL). epsilon-PL showed antimicrobial activity against Gram-positive and -negative bacteria at concentrations of 1-8 micrograms/ml. alpha-PL was less active than epsilon-PL. A chain length of at least 10 L-lysine monomers was found to be optimum for antimicrobial activity. Chemical modification of the amino groups of epsilon-PL lowered its antibacterial activity. Studies on the mode of action of epsilon-PL suggest that absorption of epsilon-PL to the bacterial cell surface plays an important role in its antibacterial activity.
Topics: Anti-Bacterial Agents; Bacteria; Bacterial Proteins; Escherichia coli; Microscopy, Electron; Oxygen Consumption; Peptides; Polylysine; Structure-Activity Relationship
PubMed: 6392269
DOI: 10.7164/antibiotics.37.1449 -
PloS One 2022ε-Poly-l-lysine (ε-PL) is a natural antimicrobial polymer with significant inhibitory activity against a broad spectrum of microorganisms, and nowadays used widely as...
ε-Poly-l-lysine (ε-PL) is a natural antimicrobial polymer with significant inhibitory activity against a broad spectrum of microorganisms, and nowadays used widely as a preservative in the food industry. In the present study, ε-PL broth was obtained from Streptomyces ahygroscopicus GIM8 fermentation in a nutrient-limited liquid medium. The in vitro antifungal activity of the broth against fruit pathogens Penicillium expansum and Colletotrichum gloeosporioides was investigated, and its usage for postharvest storage of two highly perishable fruits wax apple and guava was evaluated. Results showed that ε-PL concentration in the broth reached 0.61 g/L, and the nutrition level of the broth was low. The antifungal activity of ε-PL broth was comparable to that of the aqueous solution of ε-PL under the same concentration. Immersion with the diluted broth (200 mg/L ε-PL) markedly delayed the decline in the quality of postharvest wax apple and guava fruits during storage, and the decay incidences were also greatly decreased as compared to their respective controls (distilled water immersion). A further investigation demonstrated that the ε-PL broth immersion induced an increase in the activity of defense-related enzymes peroxidase and polyphenol oxidase in the two fruits during storage. The present study proved that the fermentation broth of ε-PL could be used as a promising alternative to high purity ε-PL and synthetic fungicides for preserving fruits at postharvest stage.
Topics: Antifungal Agents; Fruit; Polylysine; Psidium; Streptomyces; Syzygium
PubMed: 35294498
DOI: 10.1371/journal.pone.0265457 -
Nanomedicine : Nanotechnology, Biology,... Apr 2019We report the design, synthesis and efficacy of a new class of gel-like nano-carrier, or 'nanogel', prepared via templated electrostatic assembly of anionic hyaluronic...
We report the design, synthesis and efficacy of a new class of gel-like nano-carrier, or 'nanogel', prepared via templated electrostatic assembly of anionic hyaluronic acid (HA) polysaccharides with the cationic peptide amphiphile poly-L-lysine (PLL). Small molecules and proteins present during nanogel assembly become directly encapsulated within the carrier and are precisely released by tuning the nanogel HA:PLL ratio to control particle swelling. Remarkably, nanogels exhibit versatile and complimentary mechanisms of cargo delivery depending on the biologic context. For example, in mammalian cells, nanogels are rapidly internalized and escape the endosome to both deliver membrane-impermeable protein cargo into the cytoplasm and improve chemotherapeutic potency in drug resistant cancer cells. In bacteria, nanogels permeabilize microbial membranes to sensitize bacterial pathogens to the action of a loaded antibiotic. Thus, peptide nanogels represent a versatile, readily scalable and bio-responsive carrier capable of augmenting and enhancing the utility of a broad range of biomolecular cargoes.
Topics: A549 Cells; Drug Carriers; Drug Delivery Systems; Gels; Human Umbilical Vein Endothelial Cells; Humans; Hyaluronic Acid; Nanostructures; Nanotechnology; Polylysine
PubMed: 30399437
DOI: 10.1016/j.nano.2018.10.008 -
Scientific Reports Oct 2015Neural stem/progenitor cells (NSPCs) replacement therapies are the most attractive strategies to restore an injured brain. Key challenges of such therapies are enriching...
Neural stem/progenitor cells (NSPCs) replacement therapies are the most attractive strategies to restore an injured brain. Key challenges of such therapies are enriching NSPCs and directing them differentiation into specific neural cell types. Here, three biomaterial substrates Poly-L-ornithine (PO), Poly-L-lysine (PLL) and fibronectin (FN) were investigated for their effects on proliferation and differentiation of rat NSPCs, and the underlying mechanisms were also explored. The results showed PO significantly increased NSPCs proliferation and induced preferred differentiation, compared with PLL and FN. Checking protein markers of several neural cell subtypes, it is showed PO significantly induced NSPCs expressing Doublecortin (DCX) and Olig2, one for neuroblasts and young neurons and the other for young oligodendrocytes. It is suggested the ERK signaling pathway was involving in this process because an ERK antagonist U0126 could inhibit PO's effects mentioned above, as well as an ERK pathway agonist Ceramide C6 could enhance them. Given that both neurons and oligodendrocytes are the most vulnerable cells in many neurological diseases, PO-induced preferred differentiation into neurons and oligodendrocytes is a potential paradigm for NSPCs-based therapies.
Topics: Animals; Cells, Cultured; Doublecortin Protein; Fibronectins; MAP Kinase Signaling System; Neural Stem Cells; Neurogenesis; Peptides; Polylysine; Rats
PubMed: 26503112
DOI: 10.1038/srep15535 -
Nature Immunology Mar 2018
Topics: Calcium Signaling; Cell Line; Cells, Cultured; Humans; Jurkat Cells; Polylysine; T-Lymphocytes
PubMed: 29476188
DOI: 10.1038/s41590-018-0048-8 -
International Journal of Nanomedicine 2017A polyelectrolyte nanoparticle composed of PEG-PLL(--Ce6, DMA)-PLA was developed for nanomedicinal application in photodynamic therapy. These nanoparticles formed stable...
A polyelectrolyte nanoparticle composed of PEG-PLL(--Ce6, DMA)-PLA was developed for nanomedicinal application in photodynamic therapy. These nanoparticles formed stable aggregates through the hydrophobic interaction of poly(lactic acid) and demonstrated pH-dependent behaviors such as surface charge conversion and enhanced cellular uptake at acidic pH, resulting in improved phototoxicity. In vivo animal imaging revealed that the prepared PEG-PLL(--Ce6, DMA)-PLA nanoparticles effectively accumulated at the targeted tumor site through enhanced permeability and retention effects. Reversible surface charge for PEG-PLL (--Ce6, DMA)-PLA nanoparticles allows the nanoparticles to escape the immune system and concentrate on the tumor tissue. Tumor growth in the nude mice treated with the nanoparticles decreased significantly and the hydrophobic interaction in the poly(lactic acid) block could allow the incorporation of multiple drugs. Therefore, the PEG-PLL(--Ce6, DMA)-PLA nanoparticles could have considerable potential as a nanomedicinal platform for photodynamic therapy.
Topics: Animals; Chlorophyllides; Drug Carriers; Female; Humans; Hydrogen-Ion Concentration; Hydrophobic and Hydrophilic Interactions; KB Cells; Maleic Anhydrides; Mice, Inbred BALB C; Mice, Nude; Nanoparticles; Neoplasms; Photochemotherapy; Photosensitizing Agents; Polyesters; Polyethylene Glycols; Polylysine; Porphyrins
PubMed: 28883728
DOI: 10.2147/IJN.S142912