Development and pharmacological evaluation of vancomycin loaded chitosan films

Janus adhesive bio-patches with targeted drug delivery enabled anti-bacteria and pro-angiogenesis for dura mater repair

Dural injuries often result in severe complications such as cerebrospinal fluid (CSF) leakage, intracranial infections, and brain herniation, which significantly impact patient recovery and quality of life. Conventional dural repair materials, which rely on suturing to peripheral tissues, fail to promote tissue regeneration and provide sufficient CSF leakage prevention, leading to suboptimal outcomes. To address these limitations, we developed a Janus adhesive bio-patch with both antibacterial and pro-angiogenic properties to enhance dura mater repair. This bio-patch consisted of a polyacrylic acid (PAA) adhesive gel layer loaded with vancomycin and magnesium carbonate (MgCO3), integrated onto a small intestinal submucosa (SIS) extracellular matrix. It exhibited a burst strength of 20.50±2.89kPa, effectively sealing CSF leaks, while demonstrating excellent antibacterial efficacy (∼99%) and significant enhanced angiogenesis (3.47-fold higher than the control). In rat, rabbit, and dog dural injury models, the bio-patch adhered seamlessly to the injury site, successfully preventing leaks and promoting tissue regeneration. These results highlighted the Janus adhesive bio-patch as a promising solution for improving dural repair in neurosurgery, offering a safer and more effective alternative to conventional suturing techniques.

Recent advances in nanostructured delivery systems for vancomycin

Despite the development of new generations of antibiotics, vancomycin remained as a high-efficacy antibiotic for treating the infections caused by MRSA. Researchers have explored various nanoformulations, aiming to enhance the therapeutic efficacy of vancomycin. Such novel formulations improve the effectiveness of drug cargoes in treating bacterial infections and minimizing the risk of adverse effects. The vast of researches have focuses on enhancing the permeation ability of vancomycin through different biological barriers especially those of gastrointestinal tract. Increasing the drug loading and tuning the drug release from nanocarrier are other important goal for many conducted studies. This study reviews the newest nano-based formulations for vancomycin as a key antibiotic in treating hospitalized bacterial infections.

Pioneering a paradigm shift in tissue engineering and regeneration with polysaccharides and proteins-based scaffolds: A comprehensive review

In the realm of modern medicine, tissue engineering and regeneration stands as a beacon of hope, offering the promise of restoring form and function to damaged or diseased organs and tissues. Central to this revolutionary field are biological macromolecules-nature's own blueprints for regeneration. The growing interest in bio-derived macromolecules and their composites is driven by their environmentally friendly qualities, renewable nature, minimal carbon footprint, and widespread availability in our ecosystem. Capitalizing on these unique attributes, specific composites can be tailored and enhanced for potential utilization in the realm of tissue engineering (TE). This review predominantly concentrates on the present research trends involving TE scaffolds constructed from polysaccharides, proteins and glycosaminoglycans. It provides an overview of the prerequisites, production methods, and TE applications associated with a range of biological macromolecules. Furthermore, it tackles the challenges and opportunities arising from the adoption of these biomaterials in the field of TE. This review also presents a novel perspective on the development of functional biomaterials with broad applicability across various biomedical applications.

Prevention and Management of Wound Infections in Burn Patients

The leading cause of morbidity in burn patients is infection with pneumonia, urinary tract infection, cellulitis, and wound infection being the most common cause. High mortality is due to the immunocompromised status of patients and abundance of multidrug-resistant organisms in burn units. Despite the criteria set forth by American Association of Burn, the diagnosis and treatment of burn infections are not always straightforward. Topical antimicrobials, isolation, hygiene, and personal protective equipment are common preventive measures. Additionally medical and nutritional optimization of the patients is crucial to reverse the immunocompromised status triggered by burn injury.

Encapsulating Antibiotic and Protein-Stabilized Nanosilver into Sandwich-Structured Electrospun Nanofibrous Scaffolds for MRSA-Infected Wound Treatment

With the increasing prevalence of microbial infections, which results in prolonged inflammation and delayed wound healing, the development of effective and safe antimicrobial wound dressings of multiple properties remains challenging for public health. Despite their various formats, the available developed dressings with limited functions may not fulfill the diverse demands involved in the complex wound healing process. In this study, multifunctional sandwich-structured electrospinning nanofiber membranes (ENMs) were fabricated. According to the structural composition, the obtained ENMs included a hydrophilic inner layer loaded with curcumin and gentamicin sulfate, an antibacterial middle layer consisting of bovine serum albumin stabilized silver oxide nanoparticles, and a hydrophobic outer layer. The prepared sandwich-structured ENMs (SNM) exhibited good biocompatibility and killing efficacy on Escherichia coli, Staphylococcus aureus, and Methicillin-resistant S. aureus (MRSA). In particular, transcriptomic analysis revealed that SNM inactivated MRSA by inhibiting its carbohydrate and energy metabolism and reduced the bacterial resistance by downregulating mecA. In the animal experiment, SNM showed improved wound healing efficiency by reducing the bacterial load and inflammation. Moreover, 16S rDNA sequencing results indicated that SNM treatment may accelerate wound healing without observed influence on the normal skin flora. Therefore, the constructed sandwich-structured ENMs exhibited promising potential as dressings to deal with the infected wound management.

Bromelain- and Silver Nanoparticle-Loaded Polycaprolactone/Chitosan Nanofibrous Dressings for Skin Wound Healing

A cutaneous wound is caused by various injuries in the skin, which can be wrapped with an efficient dressing. Electrospinning is a straightforward adjustable technique that quickly and continuously generates nanofibrous wound dressings containing antibacterial and anti-inflammatory agents to promote wound healing. The present study investigated the physicochemical and biological properties of bromelain (BRO)- and silver nanoparticle (Ag NPs)-loaded gel-based electrospun polycaprolactone/chitosan (PCL/CS) nanofibrous dressings for wound-healing applications. Electron microscopy results showed that the obtained nanofibers (NFs) had a uniform and homogeneous morphology without beads with an average diameter of 176 ± 63 nm. The FTIR (Fourier transform infrared) analysis exhibited the loading of the components. Moreover, adding BRO and Ag NPs increased the tensile strength of the NFs up to 4.59 MPa. BRO and Ag NPs did not significantly affect the hydrophilicity and toxicity of the obtained wound dressing; however, the antibacterial activity against E. coli and S. aureus bacteria was significantly improved. The in vivo study showed that the wound dressing containing BRO and Ag NPs improved the wound-healing process within one week compared to other groups. Therefore, gel-based PCL/CS nanofibrous dressings containing BRO and Ag NPs could be a promising solution for healing skin wounds.

Evaluation of the In Vitro Antimicrobial Efficacy against Staphylococcus aureus and epidermidis of a Novel 3D-Printed Degradable Drug Delivery System Based on Polycaprolactone/Chitosan/Vancomycin-Preclinical Study

Acute and chronic bone infections, especially those caused by methicillin-resistant Staphylococcus aureus (MRSA), remains a major complication and therapeutic challenge. It is documented that local administration of vancomycin offers better results than the usual routes of administration (e.g., intravenous) when ischemic areas are present. In this work, we evaluate the antimicrobial efficacy against S. aureus and S. epidermidis of a novel hybrid 3D-printed scaffold based on polycaprolactone (PCL) and a chitosan (CS) hydrogel loaded with different vancomycin (Van) concentrations (1, 5, 10, 20%). Two cold plasma treatments were used to improve the adhesion of CS hydrogels to the PCL scaffolds by decreasing PCL hydrophobicity. Vancomycin release was measured by means of HPLC, and the biological response of ah-BM-MSCs growing in the presence of the scaffolds was evaluated in terms of cytotoxicity, proliferation, and osteogenic differentiation. The PCL/CS/Van scaffolds tested were found to be biocompatible, bioactive, and bactericide, as demonstrated by no cytotoxicity (LDH activity) or functional alteration (ALP activity, alizarin red staining) of the cultured cells and by bacterial inhibition. Our results suggest that the scaffolds developed would be excellent candidates for use in a wide range of biomedical fields such as drug delivery systems or tissue engineering applications.

Effect of Matrix Metalloproteinase 23 Accelerating Wound Healing Induced by Hydroxybutyl Chitosan

Skin wounds may cause severe financial and social burden due to the difficulties in wound healing. Original inert dressings cannot meet multiple needs in the process of wound healing. Therefore, the development of materials to accelerate healing progress is essential and urgent. In the previous study, we found that the homogeneously synthesized hydroxybutyl chitosan (HBCS) had an effective performance in promoting wound healing. Proteomic analysis of the same specimen suggested that matrix metalloproteinase 23 (MMP23) may play a key role in HBCS expediting the progress of wound healing. In this work, we aim to reveal the underlying mechanism of MMP23 in the dynamic process of cutaneous proliferation and repair period. In order to regulate the expression level of MMP23 in the local wound area, we leaded in adeno-associated virus (AAV) to specifically decreased expression quantity of MMP23 in rat skin. In contrast to the negative control groups, we found that the wound closed faster and the collagen fibers and neovascularization were significantly increased in AAV groups. These findings highlighted that MMP23 was involved in wound healing after traumatic injury, and managing the expression of MMP23 could be a potential intervention target to accelerate wound healing.

Copaiba essential oil loaded-nanocapsules film as a potential candidate for treating skin disorders: preparation, characterization, and antibacterial properties

Infections have emerged as a novel target in managing skin and mucosa diseases. Bacterial resistance to antimicrobials and biofilm elimination from surfaces remains a challenge. Because polymeric nanocapsules (NC) can increase antimicrobial activity, this study aimed to produce and characterize NC into chitosan films (CSF). Copaiba essential oil (CO) presents antimicrobial activity and was chosen to load NC. In addition, the antibacterial activity was evaluated to obtain a new biodegradable polymeric platform system with the potential to treat topical diseases associated with bacterial infections. The CO-NC produced by nanoprecipitation presented particle size lower than 250 nm, negative charge, and encapsulation efficiency higher than 70 %. Direct incorporation of CO into CSF (CO-CSF) by casting method worsened the film's characteristics. However, incorporating CO-NC into CSF (CO-NC-CSF) avoided these drawbacks demonstrating improved physical, mechanical, morphological, and topographical properties. FTIR results demonstrated possible intermolecular interactions among the polymers and CO. The CO-NC-CSF and CO-CSF presented antibacterial properties against Staphylococcus aureus, and Pseudomonas aeruginosa, especially the formulation containing 1 % of CO. These results indicated that CO-NC-CSF is a promising candidate for treating skin disorders.

Multifunctional and Smart Wound Dressings—A Review on Recent Research Advancements in Skin Regenerative Medicine

The healing of wounds is a dynamic function that necessitates coordination among multiple cell types and an optimal extracellular milieu. Much of the research focused on finding new techniques to improve and manage dermal injuries, chronic injuries, burn injuries, and sepsis, which are frequent medical concerns. A new research strategy involves developing multifunctional dressings to aid innate healing and combat numerous issues that trouble incompletely healed injuries, such as extreme inflammation, ischemic damage, scarring, and wound infection. Natural origin-based compounds offer distinct characteristics, such as excellent biocompatibility, cost-effectiveness, and low toxicity. Researchers have developed biopolymer-based wound dressings with drugs, biomacromolecules, and cells that are cytocompatible, hemostatic, initiate skin rejuvenation and rapid healing, and possess anti-inflammatory and antimicrobial activity. The main goal would be to mimic characteristics of fetal tissue regeneration in the adult healing phase, including complete hair and glandular restoration without delay or scarring. Emerging treatments based on biomaterials, nanoparticles, and biomimetic proteases have the keys to improving wound care and will be a vital addition to the therapeutic toolkit for slow-healing wounds. This study focuses on recent discoveries of several dressings that have undergone extensive pre-clinical development or are now undergoing fundamental research.

The Expanded Role of Chitosan in Localized Antimicrobial Therapy

Chitosan is one of the most studied natural origin polymers for biomedical applications. This review focuses on the potential of chitosan in localized antimicrobial therapy to address the challenges of current rising antimicrobial resistance. Due to its mucoadhesiveness, chitosan offers the opportunity to prolong the formulation residence time at mucosal sites; its wound healing properties open possibilities to utilize chitosan as wound dressings with multitargeted activities and more. We provide an unbiased overview of the state-of-the-art chitosan-based delivery systems categorized by the administration site, addressing the site-related challenges and evaluating the representative formulations. Specifically, we offer an in-depth analysis of the current challenges of the chitosan-based novel delivery systems for skin and vaginal infections, including its formulations optimizations and limitations. A brief overview of chitosan's potential in treating ocular, buccal and dental, and nasal infections is included. We close the review with remarks on toxicity issues and remaining challenges and perspectives.

Engineering Polysaccharides for Tissue Repair and Regeneration

The success of repair or regeneration depends greatly on the architecture of 3D scaffolds that finely mimic natural extracellular matrix to support cell growth and assembly. Polysaccharides have excellent biocompatibility with intrinsic biological cues and they have been extensively investigated as scaffolds for tissue engineering and regenerative medicine (TERM). The physical and biochemical structures of natural polysaccharides, however, can barely meet all the requirements of tissue-engineered scaffolds. To take advantage of their inherent properties, many innovative approaches including chemical, physical, or joint modifications have been employed to improve their properties. Recent advancement in molecular and material building technology facilitates the fabrication of advanced 3D structures with desirable properties. This review focuses on the latest progress of polysaccharide-based scaffolds for TERM, especially those that construct advanced architectures for tissue regeneration.