Synthesis, Characterization and Biocompatibility Evaluation of Novel Chitosan Lipid Micro-Systems for Modified Release of Diclofenac Sodium

Reno protective potential of taxifolin liposomes modified by chitosan in diabetic mice

The objective of this study was to develop chitosan-modified taxifolin liposomes (CTL) to enhance the treatment of diabetic kidney injury in mice and to address the limitations of taxifolin (TAX) solubility and bioavailability. Taxifolin liposomes (TL) were fabricated via film dispersion and subsequently modified with chitosan to obtain CTL. Characterisation analyses confirmed the successful construction of the liposomes. In vivo pharmacokinetic studies compared the bioavailability of CTL with those of free TAX and unmodified TL. A streptozotocin-induced diabetic nephropathy mouse model was used to investigate the reno protective effects of CTL. TL had an encapsulation efficiency (EE) of 89.61 % ± 2.51 % and drug-loading capacity (DL) of 16.07 % ± 0.70 %, while CTL had an EE of 84.57 % ± 2.95 % and DL of 14.48 % ± 0.41 %. The zeta potential of TL was -33.16 ± 5.22 mV, whereas that of CTL was +31.41 ± 3.05 mV. The particle size of TL and CTL was 136.69 ± 0.37 nm and 286.68 ± 4.99 nm, respectively. CTL showed superior bioavailability; reduced serum urea nitrogen, creatinine, total cholesterol, and triglyceride levels in diabetic mice; and improved kidney tissue damage. Importantly, CTL inhibited the activation of the NF-κB/NLRP3/caspase-1/IL-1β signalling pathway and ameliorated kidney injury. In conclusion, CTL enhanced the sustained release of TAX from simulated gastrointestinal fluids, improved pharmacokinetics, reduced pathological markers, and protected the kidneys at the molecular level.

Expression of MMP-14 and CD147 in Gingival Tissue of Patients With and Without Diabetes Mellitus Type II

Background: Diabetes mellitus (DM) is a major risk factor for the development of periodontal disease and aggravates the severity of periodontal conditions. Matrix metalloproteinases (MMPs) are known to degrade periodontal ligament attachment and bone matrix proteins. Increased expression of CD147 is associated with increased synthesis of several MMPs, being a modulator of MMP expression, including that of MMP-14. The purpose of this study was to quantify and compare the expressions of MMP-14 and CD147 in gingival tissues of patients with and without type 2 diabetes mellitus. Material and Methods: In this histological study, we included 33 subjects with periodontal disease: 16 patients with type 2 DM (test group) and 17 systemically healthy patients (control group). Tissue fragments were processed using an immunohistochemistry technique to determine immunoreactivity (IR) intensity of MMP-14 and CD147. Results: In the group of diabetes patients with periodontitis, 56.2% showed weak positive expressions (+), while 43.8% had intensely positive expressions (+++) of MMP-14. Statistically significant differences between test and control groups (p = 0.004, p = 0.883, and p = 0.002) were found for the membranous IR intensity of MMP-14. In the group of diabetes patients with periodontitis, 56.2% had moderate positive expressions (++) of CD 147, while 43.8% showed intensely positive expressions (+++). Statistically significant differences between the test and control groups were found (p = 0.001, p = 0.002, and p = 0.003) for the membranous IR intensity of CD147. Conclusions: The significantly higher membranous IR intensity for MMP-14 and CD 147 demonstrates the role of these biomarkers in the development of periodontal pathology in diabetes patients. It can be assumed that MMP-14 and CD147 could be further investigated as potential predictive biomarkers.

Enhanced Stability and In Vitro Biocompatibility of Chitosan-Coated Lipid Vesicles for Indomethacin Delivery

BACKGROUND

Lipid vesicles, especially those utilizing biocompatible materials like chitosan (CHIT), hold significant promise for enhancing the stability and release characteristics of drugs such as indomethacin (IND), effectively overcoming the drawbacks associated with conventional drug formulations.

OBJECTIVES

This study seeks to develop and characterize novel lipid vesicles composed of phosphatidylcholine and CHIT that encapsulate indomethacin (IND-ves), as well as to evaluate their in vitro hemocompatibility.

METHODS

The systems encapsulating IND were prepared using a molecular droplet self-assembly technique, involving the dissolution of lipids, cholesterol, and indomethacin in ethanol, followed by sonication and the gradual incorporation of a CHIT solution to form stable vesicular structures. The vesicles were characterized in terms of size, morphology, Zeta potential, and encapsulation efficiency and the profile release of drug was assessd. In vitro hemocompatibility was evaluated by measuring erythrocyte lysis and quantifying hemolysis rates.

RESULTS

The IND-ves exhibited an entrapment efficiency of 85%, with vesicles averaging 317.6 nm in size, and a Zeta potential of 24 mV, indicating good stability in suspension. In vitro release kinetics demonstrated an extended release profile of IND from the vesicles over 8 h, contrasting with the immediate release observed from plain drug solutions. The hemocompatibility assessment revealed that IND-ves exhibited minimal hemolysis, comparable to control groups, indicating good compatibility with erythrocytes.

CONCLUSIONS

IND-ves provide a promising approach for modified indomethacin delivery, enhancing stability and hemocompatibility. These findings suggest their potential for effective NSAID delivery, with further in vivo studies required to explore clinical applications.

Cold plasma irradiation of chitosan: A straight pathway to selective antitumor therapy

Plasma-activated chitosan (PAC) colloids for cancer treatment were obtained by using the cold atmospheric plasma technique. Chitosan solutions were irradiated by plasma ignited in argon gas and in a mixture of argon with nitrogen and oxygen gases in certain ratios. The structural modifications of chitosan and the chemical species generated in plasma were investigated by EPR, LC-MS/MS, XRD, DLS, and TGA methods. The cell viability test showed a selective cytotoxic effect on human breast carcinoma cells (MCF-7), while the human mammary epithelial cells (MCF-10A) were left unharmed. The cytotoxic effect was attributed mainly to chitooligosaccharides, but also to a synergistic effect with other compounds generated in very low concentrations in plasma, such as glyceric acid, ethyl acetate, or tricarballylic acid. The plasma irradiation improved the antioxidant activity and mucoadhesivity, while not affecting the hemocompatibility investigated by a standard hemolysis ex vivo test on mice blood. Moreover, the in vivo biocompatibility investigation at intraperitoneal administration of PAC in mice showed no statistically significant changes in the hematologic, biochemical, and immune system parameters, and no morphologic alterations of the liver and kidney. All these data indicate the cold plasma activation of chitosan as a straight method to produce biocompatible, antitumor systems.

Biocompatible hydrogels based on quaternary ammonium salts of chitosan with high antimicrobial activity as biocidal agents for disinfection

The paper reports new hydrogels based on quaternary ammonium salts of chitosan designed as biocidal products. The chitosan derivative was crosslinked with salicylaldehyde via reversible imine bonds and supramolecular self-assemble to give dynamic hydrogels which respond to environmental stimuli. The crosslinking mechanism was demonstrated by 1H NMR and FTIR spectroscopy, and X-ray diffraction and polarized light microscopy. The hydrogel nature, self-healing and thixotropy were proved by rheological investigation and visual observation, and their morphology was assessed by scanning electron microscopy. The relevant properties for application as biocidal products, such as swelling, dissolution, bioadhesiveness, antimicrobial activity and ex-vivo hemocompatibility and in vivo local toxicity and biocompatibility on experimental mice were measured and analyzed in relationship with the imination degree and the influence of each component. It was found that the hydrogels are superabsorbent, have good adhesivity to skin and various surfaces and antimicrobial activity against relevant gram-positive and gram-negative bacteria, while being hemocompatible and biocompatible. Besides, the hydrogels are easily biodegraded in soil. All these properties recommend the studied hydrogels as ecofriendly biocidal agents for living tissues and surfaces, but also open the perspectives of their use as platform for in vivo applications in tissue engineering, wound healing, or drug delivery systems.

Formulation of silymarin surface modified vesicles: In vitro characterization to cell viability assessment

Silymarin (SLR) is a poorly water-soluble bioactive compound with a wide range of therapeutic activities. Nanosized silymarin vesicles (F1-F6) were prepared by the solvent evaporation rehydration method. The silymarin vesicles were evaluated for vesicle size, surface charge, entrapment efficiency, and drug release studies. The optimized SLR lipid vesicle (F3) was further modified with the addition of the cationic polymer chitosan. After that, the modified vesicle (F3C1) was assessed for permeation flux, antimicrobial activity, cell viability, and molecular docking studies. The silymarin vesicles showed nanometric size (<250 nm), low polydispersibility index (<0.05), negative surface charge, and high SLR entrapment (85-95 %). The drug release study result demonstrated a maximum drug release of 91.2 ± 2.8 %. After adding chitosan to the surface, there was a significant change in the size, polydispersibility index, surface charge (positive), and encapsulation efficiency. The drug release was found to be prolonged, and the permeation flux was also increased in comparison to free SLR. A comparative antimicrobial result was observed in comparison to the free SLR and standard drug. The cell viability assay also demonstrated a low IC50 value for F3C1 against the cell line.

Chitosan Soft Matter Vesicles Loaded with Acetaminophen as Promising Systems for Modified Drug Release

Our study was designed to acquire, characterize and evaluate the biocompatibility of novel lipid vesicles loaded with acetaminophen (APAP) and coated with chitosan (CS). We investigated the in vitro and in vivo drug release kinetics from these systems, and we conducted assessments for both in vitro hemocompatibility and in vivo biocompatibility. For the in vivo biocompatibility evaluation, the mice were randomly divided into four groups of six animals and were treated orally as follows: control group: 0.1 mL/10 g body weight of double-distilled water; CS group: 0.1 mL/10 g body weight 1% CS solution; APAP group: 150 mg/kg body weight APAP; APAP-v group: 150 mg/kg body weight APAP-loaded lipid vesicles. The impact of APAP-v on various hematological, biochemical, and immune parameters in mice were assessed, and the harvested tissues were subjected to histopathological examination. The innovative formulations effectively encapsulating APAP within soft vesicles exhibited reasonable stability in solution and prolonged drug release in both in vitro and in vivo studies. The in vitro hemolysis test involving APAP-loaded vesicles revealed no signs of damage to red blood cells. The mice treated with APAP-v showed neither significant variances in hematological, biochemical, and immune parameters, nor structural changes in the examined organ samples, compared to the control group. APAP-v administration led to prolonged drug release. We can conclude that the APAP-v are innovative carrier systems for modifying drug release, making them promising candidates for biomedical applications.

Biodegradable trimethyl chitosan nanofiber mats by electrospinning as bioabsorbable dressings for wound closure and healing

The paper aimed to prepare quaternary chitosan-based nanofibers as bioabsorbable wound dressings. To this aim, fully biodegradable chitosan/N,N,N-trimethyl chitosan (TMC) nanofibers were designed and prepared via electrospinning, using poly(ethylene glycol) as sacrificial additive. The new biomaterials were structurally and morphologically characterized by FTIR and NMR spectroscopy, thermogravimetric analysis, X-ray diffraction and scanning electron microscopy, and their properties required for wound dressings application were investigated and discussed in detail. Thus, the nanofiber behavior was investigated by swelling, dynamic vapor sorption, and in vitro biodegradation in media mimicking the wound exudate. The mechanical properties were analysed from the stress-strain curves, the bioadhesivity from the texture analysis and the mucoadhesivity from the Zeta potential and transmittance measurements. The antimicrobial activity was assessed against S. aureus and E. coli strains, and the biocompatibility was tested in vitro on normal human dermal fibroblasts, and in vivo on rats. The application of the fiber mats with the best balance of properties as dressings on deep burn wound models in rats showed wound closure and active healing, with fully restoration of epithelia. It was concluded that the combination of chitosan with TMC into nanofibers provides new potential bioabsorbable wound dressing, opening new perspectives in regenerative medicine.