Controlled Release of Drug-Encapsulated Protein Films with Various Sodium Dodecyl Sulfate Concentrations.

Protein-based drug carriers are ideal drug-delivery platforms because of their biocompatibility, biodegradability, and low toxicity. Many types and shapes of protein-based platforms, including nanoparticles, hydrogels, films, and minipellets, have been prepared to deliver drug molecules. In this study, protein films containing the desired amounts of doxorubicin (DOX) as cancer drugs were developed using a simple mixing method. The release ratio and rate of DOXs were dependent on the surfactant concentration. The drug release ratio was controlled within the range of 20-90% depending on the amount of the surfactant used. The protein film surface was analyzed using a microscope before and after drug release, and the relationship between the degree of film swelling and the drug release ratio was discussed. Moreover, the effects of cationic surfactants on the protein film were investigated. Non-toxic conditions of the protein films were confirmed in normal cells, while the toxicity of the drug-encapsulated protein film was confirmed in cancer cells. Remarkably, it was observed that the drug-encapsulated protein film could eliminate 10-70% of cancer cells, with the extent of efficacy varying based on the surfactant amount.

Simple Formation of Cancer Drug-Containing Self-Assembled Hydrogels with Temperature and pH-Responsive Release.

The purpose of a drug delivery system is to efficiently deliver drugs to a desired target, while simultaneously reducing the side effects caused by these drugs and maximizing their efficacy. However, in the manufacture of a drug delivery system, it is difficult to control the amount of drug encapsulation. In this study, we developed a simple formation process of self-assembled hydrogels that made it easier to package the desired amount of anticancer drugs. A self-assembled hydrogel was prepared by simply mixing transferrin, dithiothreitol, and an anticancer drug in a salt solvent. The structural conditions of the hydrogel were determined in order to control the concentration of the transferrin protein, dithiothreitol, and salt in the solvent. The self-assembled hydrogels contained the desired amount of anticancer drugs. With this system, changes in pH and temperature control the release rate and the release ratio of anticancer drugs. The cytotoxicity of the drug-loaded hydrogel was evaluated, which showed that 80% of the treated cells had been killed following 48 h of incubation.

Controllable Drug-Release Ratio and Rate of Doxorubicin-Loaded Natural Composite Films Based on Polysaccharides: Evaluation of Transdermal Permeability Potential.

In drug delivery systems, it is crucial to develop a drug carrier capable of regulating both the drug-release rate and the drug-release ratio. This study proposes a method for controlling the drug-release ratio/rate using doxorubicin-loaded natural composite films composed of polysaccharides (cellulose, chitin, chitosan, or cellulose nanocrystal) and mineral substances (MMT: montmorillonite). We succeeded in controlling the doxorubicin release ratio from 25 to 88% depending on the natural polysaccharide. Likewise, the reduction rate differed depending on the type of natural polysaccharide, whereas the reduction in release was achieved by mixing MMT. Cellulose had the largest reduction in the drug release ratio, approximately 30%, and cellulose nanocrystals showed little change. Furthermore, we conducted a skin permeation test on the natural polysaccharide film with the highest release rate to confirm its transdermal permeability potential. The polysaccharide doxorubicin-loaded film sustainably released doxorubicin for 2 days, which indicated the potential of a carrier for DDS applications.

Drug-Loaded Biocompatible Chitosan Polymeric Films with Both Stretchability and Controlled Release for Drug Delivery.

Chitosan is a natural polysaccharide with the advantageous qualities of biocompatibility and biodegradability, and it has recently been spotlighted as a soft material for a sustainable society. Advantages such as these are in demand for application in various biomaterials. Although extensive studies have been conducted on the preparation of chitosan films, overcoming the problems of weak mechanical properties remains a significant barrier. In the present study, we developed stretchable doxorubicin-loaded biocompatible chitosan films by adding acetic acid in controlled concentrations. The stretchable properties of doxorubicin-loaded chitosan film at various concentrations of acetic acid were measured. Elongation to the point of breakage reached 27% with a high concentration of acetic acid, which could be described as high stretchability. The release ratio of doxorubicin from chitosan film reached 70% with a high acetic acid concentration. The cytotoxicity of doxorubicin-loaded chitosan films was measured, and cancer spheroids had completely collapsed after 7 days. According to the results of skin permeability testing, use of the doxorubicin-loaded chitosan film is a plausible choice for a drug sealant.

The relationship between sleep, gut microbiota, and metabolome in patients with depression and anxiety: A secondary analysis of the observational study.

BACKGROUND: Growing attention is paid to the association between alterations in the gut microbiota and their metabolites in patients with psychiatric disorders. Our study aimed to determine how gut microbiota and metabolomes are related to the sleep quality among patients with depression and anxiety disorders by analyzing the datasets of our previous study. METHODS: Samples were collected from 40 patients (depression: 32 patients [80.0%]); anxiety disorders: 8 patients [20.0%]) in this study. Gut microbiomes were analyzed using 16S rRNA gene sequencing and gut metabolomes were analyzed by a mass spectrometry approach. Based on the Pittsburgh Sleep Quality Index (PSQI), patients were categorized into two groups: the insomnia group (PSQI score ≥ 9, n = 20) and the non-insomnia group (PSQI score < 9, n = 20). RESULTS: The insomnia group showed a lower alpha diversity in the Chao1 and Shannon indices than the non-insomnia group after the false discovery rate (FDR) correction. The relative abundance of genus Bacteroides showed a positive correlation with PSQI scores in the non-insomnia group. The concentrations of glucosamine and N-methylglutamate were significantly higher in the insomnia group than in the non-insomnia group. CONCLUSIONS: Our findings suggest that specific taxa could affect the sleep quality among patients with depression and anxiety disorders. Further studies are needed to elucidate the impact of sleep on specific gut microbiota and metabolomes in depression and anxiety disorders.

The Potential Impact of Age on Gut Microbiota in Patients with Major Depressive Disorder: A Secondary Analysis of the Prospective Observational Study.

We aimed to investigate the impact of aging on the relationship among the composition of gut microbiota, gastrointestinal (GI) symptoms, and the course of treatment for major depressive disorder (MDD) by analyzing the datasets from our previous study. Patients with MDD were recruited, and their stools were collected at three time points (baseline, midterm, and endpoint) following the usual antidepressant treatment. Gut microbiota were analyzed using 16S rRNA gene sequencing. Patients were categorized into two groups based on their age: the late-life group over 60 years and the middle-aged group under 60 years. GI symptoms were assessed with scores of item 11 of the Hamilton Anxiety Rating Scale. One hundred and ninety samples were collected from 32 patients with MDD. Several gut microbes had higher relative abundances in the late-life group than in the middle-aged group. In addition, the late-life group showed significantly higher diversity in the Chao1 index at baseline compared with the middle-aged group. We further found possible microbial taxa related to GI symptoms in patients with late-life depression. The abundance of several bacterial taxa may contribute to GI symptoms in the late-life depression, and our findings suggest that the therapeutic targets for the application of gut microbiota may differ depending on the age group of patients with depression.