Metastasis is one of the main reasons causing death in cancer patients. It was reported that chemotherapy might induce metastasis. In order to uncover the mechanism of chemotherapy-induced metastasis and find solutions to inhibit treatment-induced metastasis, the relationship between epithelial-mesenchymal transition (EMT) and doxorubicin (DOX) treatment was investigated and a redox-sensitive small interfering RNA (siRNA) delivery system was designed. DOX-related reactive oxygen species (ROS) were found to be responsible for the invasiveness of tumor cells in vitro, causing enhanced EMT and cytoskeleton reconstruction regulated by Ras-related C3 botulinum toxin substrate 1 (RAC1). In order to decrease RAC1, a redox-sensitive glycolipid drug delivery system (chitosan-ss-stearylamine conjugate (CSO-ss-SA)) was designed to carry siRNA, forming a gene delivery system (CSO-ss-SA/siRNA) downregulating RAC1. CSO-ss-SA/siRNA exhibited an enhanced redox sensitivity compared to nonresponsive complexes in 10 mmol/L glutathione (GSH) and showed a significant safety. CSO-ss-SA/siRNA could effectively transmit siRNA into tumor cells, reducing the expression of RAC1 protein by 38.2% and decreasing the number of tumor-induced invasion cells by 42.5%. When combined with DOX, CSO-ss-SA/siRNA remarkably inhibited the chemotherapy-induced EMT in vivo and enhanced therapeutic efficiency. The present study indicates that RAC1 protein is a key regulator of chemotherapy-induced EMT and CSO-ss-SA/siRNA silencing RAC1 could efficiently decrease the tumor metastasis risk after chemotherapy.
Amines/chemistry* ; Antineoplastic Agents/adverse effects* ; Breast Neoplasms/pathology* ; Chitosan/chemistry* ; Doxorubicin/adverse effects* ; Drug Delivery Systems ; Epithelial-Mesenchymal Transition/drug effects* ; Female ; Humans ; MCF-7 Cells ; Neoplasm Metastasis/prevention & control* ; Oxidation-Reduction ; RNA, Small Interfering/administration & dosage* ; Reactive Oxygen Species/metabolism* ; rac1 GTP-Binding Protein/physiology*

Using three-dimensional printing to produce antibacterial wound dressing is a new topic that will change the production style of wound dressing industry. Combining with post-3D-printed process, a desktop fused deposition molding equipment can be used to produce wound dressing containing polyvinyl alcohol, alginate and chitosan. The wound dressing produced by FDM has good aspects of absorbency, moisture vapour transmission rate and mechanical property. After loaded with antibacterial agent iodine and silver nano particle, the antibacterial activity rate increases to 99% and it is suitable to use as antibacterial wound dressing. This method affects the production of wound dressing to a more cost-effective way, and provides a possible individualized treatment for patient in the future.
Alginates ; chemistry ; Anti-Bacterial Agents ; administration & dosage ; Bacteria ; drug effects ; Bandages ; economics ; standards ; Chitosan ; chemistry ; Humans ; Iodine ; administration & dosage ; pharmacology ; Nanoparticles ; administration & dosage ; Polyvinyl Alcohol ; chemistry ; Printing, Three-Dimensional ; Silver ; administration & dosage ; pharmacology ; Wound Healing

The present study was designed to prepare and compare bio-adhesive pellets of panax notoginseng saponins (PNS) with hydroxy propyl methyl cellulose (HPMC), chitosan, and chitosan : carbomer, explore the influence of different bio-adhesive materials on pharmacokinetics behaviors of PNSbio-adhesive pellets, and evaluate the correlation between in vivo absorption and in vitro release (IVIVC). In order to predict the in vivo concentration-time profile by the in vitro release data of bio-adhesive pellets, the release experiment was performed using the rotating basket method in pH 6.8 phosphate buffer. The PNS concentrations in rat plasma were analyzed by HPLC-MS-MS method and the relative bioavailability and other pharmacokinetic parameters were estimated using Kinetica4.4 pharmacokinetic software. Numerical deconvolution method was used to evaluate IVIVC. Our results indicated that, compared with ordinary pellets, PNS bio-adhesive pellets showed increased oral bioavailability by 1.45 to 3.20 times, increased C, and extended MRT. What's more, the release behavior of drug in HPMC pellets was shown to follow a Fickian diffusion mechanism, a synergetic function of diffusion and skeleton corrosion. The in vitro release and the in vivo biological activity had a good correlation, demonstrating that the PNS bio-adhesive pellets had a better sustained release. Numerical deconvolution technique showed the advantage in evaluation of IVIVC for self-designed bio-adhesive pellets with HPMC. In conclusion, the in vitro release data of bio-adhesive pellets with HPMC can predict its concentration-time profile in vivo.
Acrylic Resins ; Adhesives ; Animals ; Chitosan ; Drug Carriers ; Drug Liberation ; In Vitro Techniques ; Intestinal Absorption ; Male ; Methylcellulose ; Panax notoginseng ; chemistry ; Plant Extracts ; administration & dosage ; metabolism ; pharmacokinetics ; Rats, Sprague-Dawley ; Saponins ; administration & dosage ; metabolism ; pharmacokinetics

Using high pressure homogenization method combined with spray-drying, budesonide-loaded chitosan microparticles were prepared and the in vitro release profile was investigated. The microparticles were then blended with lactose using a vortex mixer, influence of mixing speed, mixing time on drug recovery rate and content homogeneity were investigated. Meanwhile, influence of lactose content on drug recovery rate, content homogeneity, powder flowability and in vitro deposition were studied. It turned out that budesonide was released from the microparicles in a sustained manner, with fine particle fraction as high as 46.0%, but the powder flowability was poor. After blending with 10 times of lactose, the drug recovery rate was 96.5%, with relative standard deviation of drug content 2.5%, and fine particle fraction of the formulation increased to 59.6% with good flowability. It's demonstrated that using a vortex mixer, budesonide sustained-release dry powder for inhalation with good recovery and content homogeneity could be prepared, the formulation had good flowability and was suitable for pulmonary inhaling.
Administration, Inhalation ; Budesonide ; chemistry ; Chemistry, Pharmaceutical ; Chitosan ; Delayed-Action Preparations ; chemistry ; Drug Carriers ; Lactose ; chemistry ; Particle Size ; Powders

OBJECTIVETo develop a dressing with desired antibacterial activity, good water maintaining ability and mechanical properties for wound healing and skin regeneration.

METHODSThe chitosan with different concentrations were added in keratin solution to form porous keratin/chitosan (KCS) scaffolds. The morphological characteristics, chemical composition, wettability, porosity, swelling ratio and degradation of the scaffolds were evaluated. The antibacterial activity was tested by using S. aureus and E. coli suspension for 2 h. And L929 fibroblast cells culture was used to evaluate the cytotoxicity of the KCS scaffolds.

RESULTSThe adding of chitosan could increase the hydrophobicity, decrease porosity, swelling ratio and degradation rate of the KCS porous scaffolds. Mechanical properties of KCS scaffolds could be enhanced and well adjusted by chitosan. KCS scaffolds could obviously decrease bacteria number. The proliferation of fibroblast cells in porous KCS patch increased firstly and then decreased with the increase of chitosan concentration. It was appropriate to add 400 μg/mL chitosan to form porous KCS scaffold for achieving best cell attachment and proliferation compared with other samples.

CONCLUSIONThe porous KCS scaffold may be used as implanted scaffold materials for promoting wound healing and skin regeneration.

Anti-Bacterial Agents ; administration & dosage ; Bandages ; Cell Line ; Cell Proliferation ; Chitosan ; Fibroblasts ; cytology ; Humans ; Keratins ; Microscopy, Electron, Scanning ; Porosity ; Spectroscopy, Fourier Transform Infrared ; Wound Healing

OBJECTIVETo prepare matrine double-sensitive colon-specific pellets and study the factors affecting its quality and evaluateing the colon-specific effects of preparation.

METHODMatrine enzyme-sensitive pellets core were prepared by carboxymethyl konjac glucomannan as the main carrier material, and coated the core by acrylic resin II and III to prepare matrine double-sensitive colon-specific pellets. The prescription and technology of the matrine colon-specific pellets were studied by the single factor investigation, through the in vitro release test and coating rate determination.

RESULTThe optimized process conditions: FeCl3 concentration is 4.0 g x L(-1), chitosan concentration is 3.0 g x L(-1), carboxymethyl konjac glucomannan concentration is 20 g x L(-1), mixed gel solution pH value is 3. The release of matrine is less than 30% in the simulation of the upper gastrointestinal medium. The release of matrine is close to 100% in simulated full gastrointestinal medium, the coating weight is 7%.

CONCLUSIONThe prepared pellets have good colon positioning effect in vitro.

Acrylic Resins ; chemistry ; Administration, Oral ; Alkaloids ; administration & dosage ; chemistry ; pharmacokinetics ; Chitosan ; chemistry ; Chlorides ; chemistry ; Colon ; metabolism ; Delayed-Action Preparations ; administration & dosage ; chemistry ; pharmacokinetics ; Drug Compounding ; methods ; Drug Delivery Systems ; methods ; Ferric Compounds ; chemistry ; Humans ; Hydrogen-Ion Concentration ; Mannans ; chemistry ; Quinolizines ; administration & dosage ; chemistry ; pharmacokinetics ; Reproducibility of Results ; Tablets, Enteric-Coated ; Time Factors

To evaluate the adjuvant effect of recombinant enterovirus 71 (EV71) subunit vaccine formulated with chitosan, rabbits were orally immunized with recombinant VP1 (rVP1) or rVP1 mixed with chitosan adjuvant. Levels of virus-specific IgG and IgA antibodies in sera, mucosal wash buffer (intestine, nasal cavity, and lung), and feces were determined by indirect enzyme-linked immunosorbent assay (ELISA). The titers of neutralizing antibodies against EV71 were determined using cytopathic effect-based neutralizing assay, and levels of cytokines (IFN-gamma and IL-4) secreted from in vitro-cultured rabbit splenic lymphocytes under antigen stimulation were also determined by ELISA. Results showed that immunization with rVP1 alone could only induce low levels of serum IgG and mucosal IgA, while rVP1 combined with chitosan adjuvant were able to induce significantly higher levels of antibodies, rVP1 can only induce neutralizing antibodies when used in combination with chitosan. Levels of IFN-gamma and IL-4 in the group immunized with rVP1 plus chitosan were significantly higher than those in the group immunized with rVP1 only or those in the control groups. Our study lays the foundation for development of oral VP1 vaccine against EV71 infection.
Adjuvants, Immunologic ; administration & dosage ; Animals ; Antibodies, Viral ; immunology ; Chitosan ; administration & dosage ; immunology ; Enterovirus A, Human ; genetics ; immunology ; Enterovirus Infections ; immunology ; prevention & control ; virology ; Female ; Humans ; Rabbits ; Vaccination ; Vaccines, Subunit ; administration & dosage ; genetics ; immunology ; Viral Proteins ; administration & dosage ; genetics ; immunology ; Viral Vaccines ; administration & dosage ; genetics ; immunology

OBJECTIVETo assess the effect of cyclosporine A (CsA) loaded in chitosan conduit on bridging the sciatic nerve defects in a rat model.

METHODSA 10 mm sciatic nerve defect was bridged using a chitosan conduit filled with 10 μl carrier-drug dilution (10 μg/L CsA). In control group, the conduit was filled with the same volume of carrier dilution alone. The regene-rated fibers were studied 4, 8 and 12 weeks after surgery.

RESULTSThe functional study confirmed faster recovery of the regenerated axons in treatment group than control group (P<0.05). There was statistically significant difference of the gastrocnemius muscle weight ratios between treatment and control groups (P<0.05). Morphometric indices of regenerated fibers showed that the number and diameter of the myelinated fibers in CsA-treated animals were significantly higher than those in control group. In immunohistochemistry, the location of reactions to S-100 in CsA group was clearly more positive than control group.

CONCLUSIONCsA loaded in a chitosan conduit results in improvement of functional recovery and quantitative morphometric indices of sciatic nerve. It is easily available without any complications compared with its systemic administration.

Animals ; Chitosan ; Cyclosporine ; administration & dosage ; pharmacology ; Immunohistochemistry ; Nerve Regeneration ; drug effects ; Rats ; Sciatic Nerve ; chemistry ; injuries

This study aimed to investigate the immune adjuvant effect and mechanism induced by chitosan nanoparticles carrying pJME/GM-CSF. In this study, plasmid DNA (pJME/GM-CSF) was encapsulated in chitosan to prepare chitosan-pJME/GM-CSF nanoparticles using a complex coacervation process. Immunohistochemistry was used to detect the type of infiltrating cells at the site of intramuscular injection. The phenotype and functional changes of splenic DCs were measured by flow cytometry after different immunogens were injected intramuscularly. The killing activity of CTLs was assessed using the lactate dehydrogenase (LDH) release assay. The preparation of chitosan-pJME/GM-CSF nanoparticles matched the expected theoretical results. Our results also found that, after pJME/GM-CSF injection, the incoming cells were a mixture of macrophages, neutrophils, and immature DCs. Meanwhile, pJME/GM-CSF increased the expression of MHC class II molecules on splenic DCs, and enhanced their Ag capture and presentation functions. Cell-mediated immunity was induced by the vaccine. Furthermore, chitosan-pJME/GM-CSF nanoparticles outperformed the administration of standard pJME/GM-CSF in terms of DC recruitment, antigen processing and presentation, and vaccine enhancement. These findings reveal that chitosan could be used as delivery vector for DNA vaccine intramuscular immunizations, and enhance pJME/GM-CSF-induced cellular immune responses.
Adjuvants, Immunologic ; administration & dosage ; Animals ; Chitosan ; administration & dosage ; immunology ; Dendritic Cells ; immunology ; virology ; Encephalitis Virus, Japanese ; genetics ; immunology ; Encephalitis, Japanese ; immunology ; prevention & control ; virology ; Female ; Granulocyte-Macrophage Colony-Stimulating Factor ; administration & dosage ; genetics ; immunology ; Humans ; Immunity, Cellular ; Japanese Encephalitis Vaccines ; administration & dosage ; genetics ; immunology ; Mice ; Mice, Inbred BALB C ; Nanoparticles ; administration & dosage ; Spleen ; immunology ; T-Lymphocytes, Cytotoxic ; immunology ; virology ; Vaccines, DNA ; administration & dosage ; genetics ; immunology

The purpose of this study is to investigate the penetration effects and mechanism of N-arginine chitosan (ACS). This novel transdermal enhancer with a mimetic structure of cell-penetration peptides was synthesized by introducing hydrophilic arginine groups to the amino-group on chitosan's side chain. The structure of ACS was confirmed by FT-IR, 1H NMR and element analysis. In addition, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) was used to study the protein conformation and the water content of stratum corneum, and the result suggested that ACS can change the orderly arrangement of the molecules in the stratum corneum, making the stack structure of keratin become loose. And ACS can increase the water content of the stratum corneurn. Inverted fluorescence microscope and flow cytometry were used to examine penetration effect of ACS on Hacat cell. The result confirmed that the uptake of ACS was enhanced with increased substitution degree of arginine by 4-8 folds compared to chitosan. In vitro penetration studies on three electrical types of drugs were carried out using three model drugs of negatively charged aspirin, positively charged terazosin and neutral drug isosorbide mononitrate by the method of Franz diffusion cells. The results showed that ACS has obviously penetration of the negatively charged drug aspirin, and certain penetration of neutral drug issorbide mononitrate, but inhibition of positively charged terazosin. In vivo imaging technology research results show that the ACS can significantly enhance the fluorescence intensity of morin, which is the auto-fluorescence anionic drug. These obtained results suggested that ACS, as a promising transdermal enhancer, can change the structure of the keratinocytes and analog penetrating peptides promote absorption, but have certain selectivity for the drug.
Administration, Cutaneous ; Animals ; Arginine ; chemical synthesis ; chemistry ; pharmacology ; Aspirin ; administration & dosage ; pharmacokinetics ; Cell Line ; Cell Survival ; drug effects ; Cell-Penetrating Peptides ; chemical synthesis ; chemistry ; pharmacology ; Chitosan ; chemical synthesis ; chemistry ; pharmacology ; Drug Carriers ; Humans ; Isosorbide Dinitrate ; administration & dosage ; analogs & derivatives ; pharmacokinetics ; Keratinocytes ; cytology ; Male ; Mice ; Prazosin ; administration & dosage ; analogs & derivatives ; pharmacokinetics ; Skin Absorption ; drug effects