ABSTRACT
Inspired by the unique functionalities of biomolecular membraneless organelles (MLOs) formed via liquid-liquid phase separation (LLPS) of intrinsically disordered proteins (IDPs) and nucleic acids, a great deal of effort has been devoted to devising phase-separated artificial subcellular dynamic compartments. These endeavors aim to unravel the molecular mechanism underlying the formation and intracellular delivery of susceptible macromolecular therapeutics. We report herein pyroglutamic acid (PGA)-based well-defined homopolymers featuring stimuli-tunable reversible self-coacervation ability. The polymer exhibits an upper critical solution temperature (UCST) transition in aqueous solutions and has the propensity to undergo cooling-induced LLPS, producing micrometer-sized liquid droplets. This phase separation phenomenon could be modulated by various factors, including polymer concentration, chain length, solution pH, and types and concentrations of different additives. These micrometer droplets are thermally reversible and encapsulate a wide variety of cargoes, including small hydrophobic fluorescent molecules, hydrophilic anticancer drugs, and fluorophore-labeled macromolecular proteins (bovine serum albumin and lysozyme). The payloads were released by exploiting the thermo/pH-mediated disassembly behavior of the coacervates, preserving the bioactivity of the sensitive therapeutics. This environmentally responsive, simple yet versatile artificial MLO model system will provide insights into the biomolecular nonionic condensates and pave the way for the de novo design of dynamic biomolecule depots.
Subject(s)
Hydrogen Bonding , Humans , Serum Albumin, Bovine/chemistry , Muramidase/chemistry , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Antineoplastic Agents/chemistry , Hydrogen-Ion Concentration , Drug Liberation , Temperature , Polymers/chemistry , Hydrophobic and Hydrophilic InteractionsABSTRACT
Cryopreservation is highly desired for long-term maintenance of the viability of living biosamples, while effective cell cryopreservation still relies heavily on the addition of dimethyl sulfoxide (DMSO) and fetal bovine serum (FBS). However, the intrinsic toxicity of DMSO is still a bottleneck, which could not only cause the clinical side effect but also induce cell genetic variants. In the meantime, the addition of FBS may bring potentially the risk of pathogenic microorganism contamination. The liquid marbles (LMs), a novel biotechnology tool for cell cryopreservation, which not only have a small volume system that facilitated recovery, but the hydrophobic shell also resisted the harm to cells caused by adverse environments. Previous LM-based cell cryopreservation relied heavily on the addition of FBS. In this work, we introduced acidic polyaspartic acid and polyglutamic acid as cryoprotectants to construct LM systems. LMs could burst in an instant to facilitate and achieve ultrarapid recovery process, and the hydrophilic carboxyl groups of the cryoprotectants could form hydrogen bonds with water molecules and further inhibit ice growth/formation to protect cells from cryoinjuries. The L929 cells could be well cryopreserved by acidic polyamino acid-based LMs. This new biotechnology platform is expected to be widely used for cell cryopreservation, which has the potential to propel LMs for the preservation of various functional cells in the future.
Subject(s)
Cell Survival , Cryopreservation , Cryoprotective Agents , Cryopreservation/methods , Animals , Mice , Cell Survival/drug effects , Cryoprotective Agents/pharmacology , Cryoprotective Agents/chemistry , Cell Line , Hydrophobic and Hydrophilic Interactions , Dimethyl Sulfoxide/chemistry , Dimethyl Sulfoxide/pharmacology , Peptides/chemistry , Peptides/pharmacology , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Polyglutamic Acid/pharmacologyABSTRACT
Anionic synthetic polypeptides are promising candidates as standalone bone-targeting drug carriers. Nevertheless, the structure-property relationship of the bone-targeting ability of polypeptides remains largely unexplored. Herein we report the optimization of the in vitro and in vivo bone-targeting ability of poly(glutamic acid)s (PGAs) by altering their chain lengths and backbone chirality. PGA 100-mers exhibited higher hydroxyapatite affinity in vitro, but their rapid macrophage clearance limited their targeting ability. Shorter PGA was therefore favored in terms of in vivo bone targeting. Meanwhile, the backbone chirality showed less significant impact on the in vitro and in vivo targeting behavior. This study highlights the modulation of structural parameters on the bone-targeting performance of anionic polypeptides, shedding light on the future design of polypeptide-based carriers.
Subject(s)
Bone and Bones , Polyglutamic Acid , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Animals , Bone and Bones/drug effects , Bone and Bones/metabolism , Mice , Durapatite/chemistry , RAW 264.7 Cells , Drug Carriers/chemistry , Macrophages/drug effects , Macrophages/metabolismABSTRACT
Polymer-homopolypeptide block copolymers are a class of bioinspired materials that combine the processability and stability of synthetic polymers with the biocompatibility and unique secondary structures of peptides, such as α-helices and ß-sheets. These properties make them ideal candidates for a wide variety of applications, for example, in the pharmaceutical field, where they are frequently explored as building blocks for polymeric micelle drug delivery systems. While homopolypeptide side chains can be furnished with an array of different moieties to impart the copolymers with desirable properties, such as stimulus responsivity, pyridine derivatives represent an underutilized functional group for this purpose. Additionally, the interplay between polypeptide side chain structure, secondary conformation, and micelle morphology is not yet well understood, particularly in the case of structural regioisomers. Therefore, in this work, a series of polymer-homopolypeptide copolymers were prepared from a poly(ethylene glycol)-b-poly(glutamic acid) (PEG-b-PGA) backbone, where the pendant carboxylic acid groups were covalently conjugated to a series of pyridine regioisomers by carbodiimide coupling. These pyridine regioisomers differed only in the position of the nitrogen heteroatom, ortho, meta or para, relative to the linking group, generating a series of PEG-b-poly(pyridinylmethyl glutamate) (PEG-b-PMG) copolymers. Following self-assembly of the copolymers in aqueous solutions, dynamic light scattering (DLS) revealed differences in micelle hydrodynamic diameter (Dh) (ranging from â¼60 to 120 nm), while transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS) revealed distinctive morphologies ranging from ellipsoidal, to cylindrical, and disc-like, suggesting that subtle changes in positional isomers in the polypeptide block may influence the micelle structure. Analysis of the PEG-b-PMG copolymer micelles by circular dichroism (CD) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy revealed that differences in the morphology were associated with changes in polypeptide secondary structure, which in turn was influenced by the position of the pyridine heteroatom. Overall, these findings contribute to the broader understanding of the relationship between polypeptide structure and micelle morphology and serve as useful insight for the rational design of polymer-polypeptide nanoparticles.
Subject(s)
Micelles , Pyridines , Pyridines/chemistry , Polyethylene Glycols/chemistry , Peptides/chemistry , Protein Structure, Secondary , Stereoisomerism , Isomerism , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Polymers/chemistryABSTRACT
Most hydrogels have poor mechanical properties, severely limiting their potential applications, and numerous approaches have been introduced to fabricate more robust and durable examples. However, these systems consist of nonbiodegradable polymers which limit their application in tissue engineering. Herein, we focus on the fabrication and investigate the influence of hydrophobic segments on ionic cross-linking properties for the construction of a tough, biodegradable hydrogel. A biodegradable, poly(γ-glutamic acid) polymer conjugated with a hydrophobic amino acid, l-phenylalanine ethyl ester (Phe), together with an ionic cross-linking group, alendronic acid (Aln) resulting in γ-PGA-Aln-Phe, was initially synthesized. Rheological assessments through time sweep oscillation testing revealed that the presence of hydrophobic domains accelerated gelation. Comparing gels with and without hydrophobic domains, the compressive strength of γ-PGA-Aln-Phe was found to be six times higher and exhibited longer stability properties in ethylenediaminetetraacetic acid solution, lasting for up to a month. Significantly, the contribution of the hydrophobic domains to the mechanical strength and stability of ionic cross-linking properties of the gel was found to be the dominant factor for the fabrication of a tough hydrogel. As a result, this study provides a new strategy for mechanical enhancement and preserves ionic cross-linked sites by the addition of hydrophobic domains. The development of tough, biodegradable hydrogels reported herein will open up new possibilities for applications in the field of biomaterials.
Subject(s)
Hydrogels , Hydrophobic and Hydrophilic Interactions , Hydrogels/chemistry , Hydrogels/chemical synthesis , Cross-Linking Reagents/chemistry , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Rheology , Compressive Strength , Ions/chemistry , Biocompatible Materials/chemistry , Phenylalanine/chemistry , Phenylalanine/analogs & derivativesABSTRACT
With continuous advances in medical technology, non-invasive embolization has emerged as a minimally invasive treatment, offering new possibilities in cancer therapy. Fluorescent labeling can achieve visualization of therapeutic agents in vivo, providing technical support for precise treatment. This paper introduces a novel in situ non-invasive embolization composite material, Au NPs@(mPEG-PLGTs), created through the electrostatic combination of L-cysteine-modified gold nanoparticles (Au NPs) and methoxy polyethylene glycol amine-poly[(L-glutamic acid)-(L-tyrosine)] (mPEG-PLGTs). Experiments were undertaken to confirm the biocompatibility, degradability, stability and performance of this tumor therapy. The research results demonstrated a reduction in tumor size as early as the fifth day after the initial injection, with a significant 90% shrinkage in tumor volume observed after a 20-day treatment cycle, successfully inhibiting tumor growth and exhibiting excellent anti-tumor effects. Utilizing near-infrared in vivo imaging, Au NPs@(mPEG-PLGTs) displayed effective fluorescence tracking within the bodies of nude BALB-c mice. This study provides a novel direction for the further development and innovation of in situ non-invasive embolization in the field, highlighting its potential for rapid, significant therapeutic effects with minimal invasiveness and enhanced safety.
Subject(s)
Gold , Metal Nanoparticles , Mice, Inbred BALB C , Mice, Nude , Polyethylene Glycols , Gold/chemistry , Animals , Metal Nanoparticles/chemistry , Metal Nanoparticles/therapeutic use , Mice , Polyethylene Glycols/chemistry , Cell Line, Tumor , Humans , Hydrogen-Ion Concentration , Embolization, Therapeutic , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivativesABSTRACT
Injectable adhesive hydrogels combining rapid gelling with robust adhesion to wet tissues are highly required for fast hemostasis in surgical and major trauma scenarios. Inspired by the cross-linking mechanism of mussel adhesion proteins, we developed a bionic double-crosslinked (BDC) hydrogel of poly (γ-glutamic acid) (PGA)/poly (N-(2-hydroxyethyl) acrylamide) (PHEA) fabricated through a combination of photo-initiated radical polymerization and hydrogen bonding cross-linking. The BDC hydrogel exhibited an ultrafast gelling process within 1 s. Its maximum adhesion strength to wet porcine skin reached 254.5 kPa (9 times higher than that of cyanoacrylate (CA) glue) and could withstand an ultrahigh burst pressure of 626.4 mmHg (24 times higher than that of CA glue). Notably, the BDC hydrogel could stop bleeding within 10 s from a rat liver incision 10 mm long and 5 mm deep. The wound treated with the BDC hydrogel healed faster than the control groups, underlining the potential for emergency rescue and wound care scenarios.
Subject(s)
Hydrogels , Polyglutamic Acid , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Animals , Hydrogels/chemistry , Rats , Pressure , Cross-Linking Reagents/chemistry , Wound Healing/drug effects , Swine , Acrylamides/chemistryABSTRACT
The clinical application of 7-ethyl hydroxy-camptothecin (SN-38) maintains challenges not only due to its poor solubility and stability but also the lack of effective carriers to actively deliver SN-38 to deep tumor sites. Although SN-38-based nanomedicines could improve the solubility and stability from different aspects, the tumor targeting efficiency remains very low. Leveraging the hypoxic taxis of bifidobacteria bifidum (B. bifi) to the deep tumor area, we report SN-38-based nanomedicines-engineered bifidobacterial complexes for effective tumor-targeted delivery. Firstly, SN-38 was covalently coupled with poly-L-glutamic acid (L-PGA) and obtained soluble polymeric prodrug L-PGA-SN38 to improve its solubility and stability. To prolong the drug release, L-PGA-SN38 was mildly complexed with chitosan to form nanomedicines, and nanomedicines engineered B. bifi were further elaborated via electrostatic interaction of the excess of cationic chitosan shell from nanomedicines and anionic teichoic acid from B. bifi. The engineered B. bifi complexes inherited the bioactivity of native B. bifi and exhibited distinctly enhanced accumulation at the tumor site. More importantly, significantly elevated anti-tumor efficacy was achieved after the treatment of CS-L-PGA-SN38 NPs/B. bifi complexes, with favorable tumor suppression up to 80%. Such a B. bifi-mediated delivery system offers a promising platform for effective drug delivery and enhanced drug accumulation in the hypoxia deep tumor with superior anti-tumor efficacy.
Subject(s)
Chitosan , Colorectal Neoplasms , Irinotecan , Nanomedicine , Polyglutamic Acid , Irinotecan/administration & dosage , Irinotecan/pharmacology , Chitosan/chemistry , Colorectal Neoplasms/drug therapy , Animals , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Humans , Nanomedicine/methods , Drug Liberation , Drug Carriers/chemistry , Drug Delivery Systems , Antineoplastic Agents, Phytogenic/administration & dosage , Antineoplastic Agents, Phytogenic/pharmacology , Mice , Camptothecin/administration & dosage , Camptothecin/analogs & derivatives , Camptothecin/chemistry , Camptothecin/pharmacology , Mice, Inbred BALB C , Cell Line, Tumor , Bifidobacterium bifidum , Mice, Nude , FemaleABSTRACT
Establishing a physical barrier between the peritoneum and the cecum is an effective method to reduce the risk of postoperative abdominal adhesions. Meloxicam (MX), a nonsteroidal anti-inflammatory drug has also been applied to prevent postoperative adhesions. However, its poor water solubility has led to low bioavailability. Herein, we developed an injectable hydrogel as a barrier and drug carrier for simultaneous postoperative adhesion prevention and treatment. A third-generation polyamide-amine dendrimer (G3) was exploited to dynamically combine with MX to increase the solubility and the bioavailability. The formed G3@MX was further used to crosslink with poly-γ-glutamic acid (γ-PGA) to prepare a hydrogel (GP@MX hydrogel) through the amide bonding. In vitro and in vivo experiments evidenced that the hydrogel had good biosafety and biodegradability. More importantly, the prepared hydrogel could control the release of MX, and the released MX is able to inhibit inflammatory responses and balance the fibrinolytic system in the injury tissues in vivo. The tunable rheological and mechanical properties (compressive moduli: from ⼠57.31 kPa to ⼠98.68 kPa;) and high anti-oxidant capacity (total free radical scavenging rate of ⼠94.56 %), in conjunction with their syringeability and biocompatibility, indicate possible opportunities for the development of advanced hydrogels for postoperative tissue adhesions management.
Subject(s)
Dendrimers , Hydrogels , Meloxicam , Nylons , Polyglutamic Acid , Hydrogels/chemistry , Hydrogels/pharmacology , Animals , Polyglutamic Acid/chemistry , Polyglutamic Acid/pharmacology , Polyglutamic Acid/analogs & derivatives , Nylons/chemistry , Tissue Adhesions/prevention & control , Dendrimers/chemistry , Dendrimers/pharmacology , Meloxicam/chemistry , Meloxicam/pharmacology , Meloxicam/administration & dosage , Mice , Inflammation/prevention & control , Inflammation/drug therapy , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Rats , Rats, Sprague-Dawley , Fibrinolysis/drug effects , Postoperative Complications/prevention & control , Particle Size , Injections , Drug Carriers/chemistryABSTRACT
In this study, we determined effects of an anionic siRNA delivery vector, siRNA ternary complex, which is constructed with biodegradable dendrigraft poly-L-lysine (DGL) and γ-polyglutamic acid (γ-PGA) on the melanoma cells and melanoma lung metastasis. The siRNA ternary complex showed high cellular uptake and silencing effect in melanoma cell line B16-F10/Luc cells. After intravenous administration of the siRNA ternary complex, high silencing effect was also observed in the lung of B16-F10/Luc melanoma metastasis model mice. Therefore, we applied vascular endothelial growth factor (VEGF)-siRNA on the siRNA ternary complex and determined the effect on the melanoma lung metastasis. The siRNA ternary complex containing VEGF-siRNA reduced VEGF protein levels significantly in in vitro and in vivo, and the complex successfully inhibited melanoma lung metastasis. This biodegradable and effective siRNA delivery vector, siRNA ternary complex, could be available for clinical trials.
Subject(s)
Lung Neoplasms , Melanoma, Experimental , Polyglutamic Acid , Polylysine , RNA, Small Interfering , Vascular Endothelial Growth Factor A , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/pharmacology , Animals , Lung Neoplasms/secondary , Lung Neoplasms/pathology , Mice , Melanoma, Experimental/pathology , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Cell Line, Tumor , Vascular Endothelial Growth Factor A/genetics , Polylysine/chemistry , Mice, Inbred C57BL , Gene Silencing , Melanoma/pathology , Melanoma/geneticsABSTRACT
Bacterial cellulose (BC) is an ideal candidate material for drug delivery, but the disbalance between the swelling behavior and mechanical properties limits its application. In this work, covalent crosslinking of γ-polyglutamic acid (γ-PGA) with the chitosan oligosaccharide (COS) embedded in BC was designed to remove the limitation. As a result, the dosage, time, and batch of COS addition significantly affected the mechanical properties and the yield of bacterial cellulose complex film (BCCF). The addition of 2.25 % COS at the incubation time of 0.5, 1.5, and 2 d increased the Young's modulus and the yield by 5.65 and 1.42 times, respectively, but decreased the swelling behavior to 1774 %, 46 % of that of native BC. Covalent γ-PGA transformed the dendritic structure of BCCF into a spider network, decreasing the porosity and increasing the swelling behavior by 3.46 times. The strategy balanced the swelling behavior and mechanical properties through tunning hydrogen bond, electrostatic interaction, and amido bond. The modified BCCF exhibited a desired behavior of benzalkonium chlorides transport, competent for drug delivery. Thereby, the strategy will be a competent candidate to modify BC for such potential applications as wound dressing, artificial skin, scar-inhibiting patch, and so on.
Subject(s)
Cellulose , Chitosan , Oligosaccharides , Polyglutamic Acid , Polyglutamic Acid/analogs & derivatives , Chitosan/chemistry , Cellulose/chemistry , Oligosaccharides/chemistry , Polyglutamic Acid/chemistry , Mechanical Phenomena , Bacteria/drug effects , Elastic ModulusABSTRACT
Curcumin was widely designed as nanoparticles to remove application restrictions. The occurrence of flocculation is a primary factor limiting the application of the curcumin nano-delivery system. To enhance the environmental stress resistance and functional properties of shellac-curcumin nanoparticles (S-Cur-NPs), γ-polyglutamic acid (γ-PGA) was utilized as an anti-flocculant. The encapsulation efficiency and loading capacity of S-Cur-NPs were also improved with γ-PGA incorporation. FTIR and XRD analysis confirmed the presence of amorphous characteristics in S-Cur-NPs and the combination of γ-PGA and shellac was driven by hydrogen bonding. The hydrophilic, thermodynamic, and surface potential of S-Cur-NPs was improved by the incorporation of γ-PGA. This contribution of γ-PGA on S-Cur-NPs effectively mitigated the flocculation occurrence during heating, storage, and in-vitro digestive treatment. Furthermore, it was revealed that γ-PGA enhanced the antibacterial and antioxidant properties of S-Cur-NPs and effectively protected the functional activity against heating, storage, and in-vitro digestion. Release studies conducted in simulated gastrointestinal fluids revealed that S-Cur-NPs have targeted intestinal release properties. Overall, the design of shellac with γ-PGA was a promising strategy to relieve the application stress of shellac and curcumin in the food industry.
Subject(s)
Antioxidants , Curcumin , Flocculation , Nanoparticles , Polyglutamic Acid , Curcumin/chemistry , Curcumin/pharmacology , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Polyglutamic Acid/pharmacology , Nanoparticles/chemistry , Antioxidants/chemistry , Antioxidants/pharmacology , Drug Carriers/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Drug Delivery Systems , Drug Liberation , Hydrophobic and Hydrophilic InteractionsABSTRACT
Redox nanoparticles have been extensively developed for chemotherapy. However, the intracellular oxidative stress induced by constant aberrant glutathione (GSH), reactive oxygen species (ROS) and gamma-glutamyl transpeptidase (GGT) homeostasis remains the primary cause of evading tumor apoptosis. Herein, an oxidative stress-amplification strategy was designed using a pH-GSH-H2O2-GGT sensitive nano-prodrug for precise synergistic chemotherapy. The disulfide bond- conjugated doxorubicin prodrug (DOX-ss) was constructed as a GSH-scavenger. Then, phenylboronic acid (PBA), DOX-ss and poly (γ-glutamic acid) (γ-PGA) were successively conjugated using chitosan oligosaccharide (COS) to obtain the nano-prodrug PBA-COS-ss-DOX/γ-PGA. The PBA-COS-ss-DOX/γ-PGA prodrug could tightly attach to the polymer chain segment by atom transfer radical polymerization. Simultaneously, the drug interacted relatively weakly with the polymer by encapsulating ionic crosslinkers in DOX@PBA-COS/γ-PGA. The disulfide bond of the DOX-ss prodrug as a GSH-scavenger could be activated using overexpressed GSH to release DOX. Particularly, PBA-COS-ss-DOX/γ-PGA could prevent premature drug leakage and facilitate DOX delivery by GGT-targeting and intracellular H2O2-cleavable linker in human hepatocellular carcinoma (HepG2) cells. Concurrently, the nano-prodrug induced strong oxidative stress and tumor cell apoptosis. Collectively, the pH-GSH-H2O2-GGT responsive nano-prodrug shows potential for synergistic tumor therapy.
Subject(s)
Chitosan , Doxorubicin , Nanoparticles , Oligosaccharides , Oxidative Stress , Prodrugs , Chitosan/chemistry , Oxidative Stress/drug effects , Prodrugs/chemistry , Prodrugs/pharmacology , Humans , Doxorubicin/pharmacology , Doxorubicin/chemistry , Oligosaccharides/chemistry , Oligosaccharides/pharmacology , Nanoparticles/chemistry , Glutathione/metabolism , Glutathione/chemistry , Hep G2 Cells , Reactive Oxygen Species/metabolism , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Hydrogen Peroxide/chemistry , Drug Liberation , Drug Carriers/chemistry , Apoptosis/drug effects , gamma-Glutamyltransferase/metabolism , Boronic Acids/chemistry , Hydrogen-Ion ConcentrationABSTRACT
Responsive nanomaterials hold significant promise in the treatment of bacterial infections by recognizing internal or external stimuli to achieve stimuli-responsive behavior. In this study, we present an enzyme-responsive polyelectrolyte complex micelles (PTPMN) with α-helical cationic polypeptide as a coacervate-core for the treatment of Escherichia coli (E. coli) infection. The complex was constructed through electrostatic interaction between cationic poly(glutamic acid) derivatives and phosphorylation-modified poly(ethylene glycol)-b-poly(tyrosine) (PEG-b-PPTyr) by directly dissolving them in aqueous solution. The cationic polypeptide adopted α-helical structure and demonstrated excellent broad-spectrum antibacterial activity against both Gram-negative and Gram-positive bacteria, with a minimum inhibitory concentration (MIC) as low as 12.5 µg mL-1 against E. coli. By complexing with anionic PEG-b-PPTyr, the obtained complex formed ß-sheet structures and exhibited good biocompatibility and low hemolysis. When incubated in a bacterial environment, the complex cleaved its phosphate groups triggered by phosphatases secreted by bacteria, exposing the highly α-helical conformation and restoring its effective bactericidal ability. In vivo experiments confirmed accelerated healing in E. coli-infected wounds.
Subject(s)
Anti-Bacterial Agents , Escherichia coli , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/administration & dosage , Escherichia coli/drug effects , Animals , Microbial Sensitivity Tests , Polyelectrolytes/chemistry , Polyelectrolytes/pharmacology , Peptides/chemistry , Peptides/pharmacology , Protein Conformation, alpha-Helical , Micelles , Escherichia coli Infections/drug therapy , Hemolysis/drug effects , Polyethylene Glycols/chemistry , Polyethylene Glycols/pharmacology , Mice , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Polyglutamic Acid/pharmacology , HumansABSTRACT
Intrinsically disordered proteins (IDPs) do not have a well-defined folded structure but instead behave as extended polymer chains in solution. Many IDPs are rich in glycine residues, which create steric barriers to secondary structuring and protein folding. Inspired by this feature, we have studied how the introduction of glycine residues influences the secondary structure of a model polypeptide, poly(l-glutamic acid), a helical polymer. For this purpose, we carried out ring-opening copolymerization with γ-benzyl-l-glutamate and glycine N-carboxyanhydride (NCA) monomers. We aimed to control the glycine distribution within PBLG by adjusting the reactivity ratios of the two NCAs using different reaction conditions (temperature, solvent). The relationship between those conditions, the monomer distributions, and the secondary structure enabled the design of intrinsically disordered polypeptides when a highly gradient microstructure was achieved in DMSO.
Subject(s)
Anhydrides , Glycine , Intrinsically Disordered Proteins , Polymerization , Glycine/chemistry , Intrinsically Disordered Proteins/chemistry , Anhydrides/chemistry , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Protein Structure, Secondary , Peptides/chemistry , Protein FoldingABSTRACT
Chitosan acts as a versatile carrier in polymeric nanoparticle (NP) for diverse drug administration routes. Delivery of antioxidants, such as quercetin (Qu) showcases potent antioxidant and anti-inflammatory properties for reduction of various cardiovascular diseases, but low water solubility limits uptake. To address this, we developed a novel layer-by-layer zein/gamma-polyglutamic acid (γPGA)/low-molecular-weight chitosan (LC)/fucoidan NP for encapsulating Qu and targeting inflamed vessel endothelial cells. We used zein (Z) and γPGA (r) to encapsulate Qu (Qu-Zr NP) exhibited notably higher encapsulation efficiency compared to zein alone. Qu-Zr NP coated with LC (Qu-ZrLC2 NP) shows a lower particle size (193.2 ± 2.9 nm), and a higher zeta potential value (35.2 ± 0.4 mV) by zeta potential and transmission electron microscopy analysis. After coating Qu-ZrLC2 NP with fucoidan, Qu-ZrLC2Fa NP presented particle size (225.16 ± 0.92 nm), zeta potential (-25.66 ± 0.51 mV) and maintained antioxidant activity. Further analysis revealed that Qu-ZrLC2Fa NP were targeted and taken up by HUVEC cells and EA.hy926 endothelial cells. Notably, we observed Qu-ZrLC2Fa NP targeting zebrafish vessels and isoproterenol-induced inflamed vessels of rat. Our layer-by-layer formulated zein/γPGA/LC/fucoidan NP show promise as a targeted delivery system for water-insoluble drugs. Qu-ZrLC2Fa NP exhibit potential as an anti-inflammatory therapeutic for blood vessels.
Subject(s)
Antioxidants , Chitosan , Layer-by-Layer Nanoparticles , Polyglutamic Acid , Polysaccharides , Quercetin , Zebrafish , Zein , Animals , Humans , Male , Rats , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Blood Vessels/drug effects , Chitosan/chemistry , Drug Carriers/chemistry , Human Umbilical Vein Endothelial Cells/drug effects , Inflammation/drug therapy , Inflammation/pathology , Layer-by-Layer Nanoparticles/chemistry , Molecular Weight , Particle Size , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Polyglutamic Acid/pharmacology , Polysaccharides/chemistry , Polysaccharides/pharmacology , Quercetin/pharmacology , Quercetin/chemistry , Zein/chemistryABSTRACT
Nattokinase (NK) is a thrombolytic enzyme extracted from natto, which can be used to prevent and treat blood clots. However, it is sensitive to the environment, especially the acidic environment of human stomach acid, and its effect of oral ingestion is minimal. This study aims to increase NK's oral and storage stability by embedding NK in microcapsules prepared with chitosan (CS) and γ-polyglutamic acid (γ-PGA). The paper prepared a double-layer NK oral delivery system by layer self-assembly and characterized its stability and in vitro simulated digestion. According to the research results, the bilayer putamen structure has a protective effect on NK, which not only maintains high activity in various environments (such as acid-base, high temperature) and long-term storage (60 days), but also effectively protects the loaded NK from being destroyed in gastric fluid and achieves its slow release. This work has proved the feasibility of the design of bilayer putamen structure in oral administration and has good fibrolytic activity. Therefore, the novel CS/γ-PGA microcapsules are expected to be used in nutraceutical delivery systems.
Subject(s)
Chitosan , Drug Stability , Fibrinolytic Agents , Polyglutamic Acid , Subtilisins , Chitosan/chemistry , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Subtilisins/metabolism , Subtilisins/chemistry , Fibrinolytic Agents/chemistry , Fibrinolytic Agents/administration & dosage , Fibrinolytic Agents/pharmacology , Administration, Oral , Humans , Digestion/drug effects , Capsules , Drug Delivery Systems/methods , Drug Compounding/methods , Drug Liberation , Drug Carriers/chemistryABSTRACT
Advancements in medicine have led to continuous enhancements and innovations in wound dressing materials, making them pivotal in medical care. We used natural biological macromolecules, γ-polyglutamic acid and gum arabic as primary raw materials to create nanofibers laden with curcumin by blending electrostatic spinning technology in the current investigation. These nanofibers were meticulously characterized using fluorescence microscopy, scanning electron microscopy, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Our comprehensive analyses confirmed the successful encapsulation of curcumin within the nanofiber carrier and it has uniform diameter, good water absorption and mechanical properties. Subsequently, we evaluated the antimicrobial effects of these curcumin-loaded nanofibers against Staphylococcus aureus through an oscillating flask method. We created a mouse model with acute full-thickness skin defects to further investigate the wound healing potential. We conducted various biochemical assays to elucidate the mechanism of action. The results revealed that curcumin nanofibers profoundly impacted wound healing. They bolstered the expression of TGF-ß1 and VEGF and reduced the expression of inflammatory factors, leading to an accelerated re-epithelialization process, enhanced wound contraction, and increased regeneration of new blood vessels and hair follicles. Furthermore, these nanofibers positively influenced the proportion of three different collagen types. This comprehensive study underscores the remarkable potential of curcumin-loaded nanofibers to facilitate wound healing and lays a robust experimental foundation for developing innovative, natural product-based wound dressings.
Subject(s)
Curcumin , Gum Arabic , Nanofibers , Polyglutamic Acid , Staphylococcus aureus , Wound Healing , Gum Arabic/chemistry , Nanofibers/chemistry , Curcumin/pharmacology , Curcumin/chemistry , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Polyglutamic Acid/pharmacology , Wound Healing/drug effects , Animals , Mice , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Bandages , Skin/drug effectsABSTRACT
Particles with a porous structure can lead to quick hemostasis and provide a good matrix for cell proliferation during wound healing. Recently, many particle-based wound healing materials have been clinically applied. However, these products show good hemostatic ability but with poor wound healing ability. To solve this problem, this study fabricated APGG composite particles using yeast ß-glucan (obtained from Saccharomyces cerevisiae), sodium alginate, and γ-polyglutamic acid as the starting materials. The structure of yeast ß-glucan was modified with many carboxymethyl groups to obtain carboxymethylated ß-glucan, which could coordinate with Ca2+ ions to form a crosslinked structure. A morphology study indicated that the APGG particles showed an irregular spheroidal structure with a low density (<0.1 g cm-3) and high porosity (>40%). An in vitro study revealed that the particles exhibited a low BCI value, low hemolysis ratio, and good cytocompatibility against L929 cells. The APGG particles could quickly stop bleeding in a mouse liver injury model and exhibited better hemostatic ability than the commercially available product Celox. Furthermore, the APGG particles could accelerate the healing of non-infected wounds, and the expression levels of CD31, α-SMA, and VEGF related to angiogenesis were significantly enhanced.
Subject(s)
Alginates , Hemostasis , Polyglutamic Acid , Polyglutamic Acid/analogs & derivatives , Saccharomyces cerevisiae , Wound Healing , beta-Glucans , Animals , Wound Healing/drug effects , Alginates/chemistry , Alginates/pharmacology , Polyglutamic Acid/chemistry , Polyglutamic Acid/pharmacology , beta-Glucans/chemistry , beta-Glucans/pharmacology , Mice , Hemostasis/drug effects , Cell Line , Hemostatics/pharmacology , Hemostatics/chemistry , Hemostatics/administration & dosage , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , MaleABSTRACT
Tumor penetration is a critical determinant of the therapy efficacy of nanomedicines. However, the dense extracellular matrix (ECM) in tumors significantly hampers the deep penetration of nanomedicines, resulting in large drug-untouchable areas and unsatisfactory therapy efficacy. Herein, we synthesized a third-generation PAMAM-cored multiarm copolymer and modified the polymer with collagenase to enhance its tumor penetration. Each arm of the copolymer was a diblock copolymer of poly(glutamic acid)-b-poly(carboxybetaine), in which the polyglutamic acid block with abundant side groups was used to link the anticancer agent doxorubicin through the pH-sensitive acylhydrazone linkage, and the zwitterionic poly(carboxybetaine) block provided desired water solubility and anti-biofouling capability. The collagenase was conjugated to the ends of the arms via the thiol-maleimide reaction. We demonstrated that the polymer-bound collagenase could effectively catalyze the degradation of the collagen in the tumor ECM, and consequently augmented the tumor penetration and antitumor efficacy of the drug-loaded polymers.