Electrospun fixed dose combination fibers for the treatment of cardiovascular disease

Co-Delivery of Dragon's Blood and Alkanna tinctoria Extracts Using Electrospun Nanofibers: In Vitro and In Vivo Wound Healing Evaluation in Diabetic Rat Model

The increasing prevalence of diabetic wounds presents a significant challenge due to the difficulty of natural healing and various obstacles. Dragon's blood (DB) and Alkanna tinctoria (AT) are well recognized for their potent healing abilities, which include potent antibacterial and anti-inflammatory activities. In this study, electrospun nanofibers (NFs) based on polyvinyl pyrrolidone (PVP) were co-loaded with both DB and AT, aiming to magnify their efficacy as wound-dressing applications for diabetic wound healing. The evaluation of these NFs as wound dressings was conducted using a streptozotocin-induced diabetic rat model. Electrospun NFs were prepared using the electrospinning of the PVP polymer, resulting in nanofibers with consistent, smooth surfaces. The loading capacity (LC) of AT and DB into NFs was 64.1 and 70.4 µg/mg, respectively, while in the co-loaded NFs, LC was 49.6 for AT and 57.2 µg/mg for DB. In addition, X-ray diffraction (XRD) revealed that DB and AT were amorphously dispersed within the NFs. The loaded NFs showed a dissolution time of 30 s in PBS (pH 7.4), which facilitated the release of AT and DB (25-38% after 10 min), followed by a complete release achieved after 180 min. The antibacterial evaluation demonstrated that the DB-AT mixture had potent activity against Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). Along with that, the DB-AT NFs showed effective growth inhibition for both P. aeruginosa and S. aureus compared to the control NFs. Moreover, wound healing was evaluated in vivo in diabetic Wistar rats over 14 days. The results revealed that the DB-AT NFs improved wound healing within 14 days significantly compared to the other groups. These results highlight the potential application of the developed DB-AT NFs in wound healing management, particularly in diabetic wounds.

Fabrication and evaluation of ribavirin-loaded electrospun nanofibers as an antimicrobial wound dressing

Background

Skin is regarded as an essential first line of defense against harmful pathogens and it hosts an ecosystem of microorganisms that create a widely diverse skin microbiome. In chronic wounds, alterations in the host-microbe interactions occur forming polymicrobial biofilms that hinder the process of wound healing. Ribavirin, an antiviral drug, possesses antimicrobial activity, especially against Pseudomonas aeruginosa and Candida albicans, which are known as the main opportunistic pathogens in chronic wounds.

Rationale

In this study, electrospun nanofiber systems loaded with ribavirin were developed as a potential wound dressing for topical application in chronic wounds. Ribavirin was chosen in this study owing to the emerging cases of antimicrobial (antibiotics and antifungal) resistance and the low attempts to discover new antimicrobial agents, which encouraged the repurposing use of current medication as an alternative solution in case of resistance to the available agents. Additionally, the unique mechanism of action of ribavirin, i.e., perturbing the bacterial virulence system without killing or stopping their growth and rendering the pathogens disarmed, might be a promising choice to prevent drug resistance. Cyclodextrin (CD) was utilized to formulate ribavirin as an electrospun nanofibers delivery system to enhance the absorption and accelerate the release of ribavirin for topical use.

Results

The results demonstrated a successful ribavirin nanofibers fabrication that lacked beads and pores on the nanofibrous surfaces. Ribavirin underwent a physical transformation from crystalline to amorphous form, as confirmed by X-ray diffraction analysis. This change occurred due to the molecular dispersion after the electrospinning process. Additionally, the CD enhanced the encapsulation efficiency of ribavirin in the nanofibers as observed from the drug-loading results. Polyvinylpyrrolidone (PVP) and CD increased ribavirin released into the solution and the disintegration of fibrous mats which shrank and eventually dissolved into a gel-like substance as the ribavirin-loaded fibers began to break down from their border toward the midpoint. Cytotoxicity of ribavirin and CD was evaluated against human dermal fibroblasts (HFF-1) and the results showed a relatively safe profile of ribavirin upon 24-hour cell exposure, while CD was safe within 24- and 48-hour.

Conclusion

This study provides valuable insights into the potential application of our nanofibrous system for treating chronic wounds; however, further antimicrobial and in-vivo studies are required to confirm its safety and effectiveness.

Biologics, theranostics, and personalized medicine in drug delivery systems

The progress in human disease treatment can be greatly advanced through the implementation of nanomedicine. This approach involves targeted and cell-specific therapy, controlled drug release, personalized dosage forms, wearable drug delivery, and companion diagnostics. By integrating cutting-edge technologies with drug delivery systems, greater precision can be achieved at the tissue and cellular levels through the use of stimuli-responsive nanoparticles, and the development of electrochemical sensor systems. This precision targeting - by virtue of nanotechnology - allows for therapy to be directed specifically to affected tissues while greatly reducing side effects on healthy tissues. As such, nanomedicine has the potential to transform the treatment of conditions such as cancer, genetic diseases, and chronic illnesses by facilitating precise and cell-specific drug delivery. Additionally, personalized dosage forms and wearable devices offer the ability to tailor treatment to the unique needs of each patient, thereby increasing therapeutic effectiveness and compliance. Companion diagnostics further enable efficient monitoring of treatment response, enabling customized adjustments to the treatment plan. The question of whether all the potential therapeutic approaches outlined here are viable alternatives to current treatments is also discussed. In general, the application of nanotechnology in the field of biomedicine may provide a strong alternative to existing treatments for several reasons. In this review, we aim to present evidence that, although in early stages, fully merging advanced technology with innovative drug delivery shows promise for successful implementation across various disease areas, including cancer and genetic or chronic diseases.

Application of Electrospun Drug-Loaded Nanofibers in Cancer Therapy

In the 21st century, chemotherapy stands as a primary treatment method for prevalent diseases, yet drug resistance remains a pressing challenge. Utilizing electrospinning to support chemotherapy drugs offers sustained and controlled release methods in contrast to oral and implantable drug delivery modes, which enable localized treatment of distinct tumor types. Moreover, the core-sheath structure in electrospinning bears advantages in dual-drug loading: the core and sheath layers can carry different drugs, facilitating collaborative treatment to counter chemotherapy drug resistance. This approach minimizes patient discomfort associated with multiple-drug administration. Electrospun fibers not only transport drugs but can also integrate metal particles and targeted compounds, enabling combinations of chemotherapy with magnetic and heat therapies for comprehensive cancer treatment. This review delves into electrospinning preparation techniques and drug delivery methods tailored to various cancers, foreseeing their promising roles in cancer treatment.

Molecular complexes of drug combinations: A review of cocrystals, salts, coamorphous systems and amorphous solid dispersions

As the advancements in the medical technology and healthcare develop through the years, combinational therapy has evolved to be an important treatment modality in many disease settings, including cancer, cardiovascular disease and infectious diseases. In an effort to alleviate "pill burden" and improve patient compliance, fixed dose combinations (FDCs) have been developed to be used as effective therapeutics. Among all FDCs, the category of drug-drug molecular complexes has been proven an efficient methodology in designing and treating diseases, with many drugs being approved. Among all drug-drug molecular complexes, drug-drug cocrystals, salts, coamorphous systems and solid dispersions have been successfully developed and many have been approved by the FDA. In this review, we dwell deeply into the molecular mechanisms behind the different types of drug-drug molecular complexes, including the key functional groups involved in the intermolecular interactions, the applications of each category of molecular complexes, as well as the advantages and challenges thereof. This comprehensive review provides useful insights into the practical design and manufacture of drug-drug molecular complexes and points out the future direction for the development of new advantageous combinational therapies that benefit more patients.

Electrospun polymer fibers modified with FK506 for the long-term treatment of acute cardiac allograft rejection in a heart transplantation model

FK506, a first-line immunosuppressant, is routinely administered orally and intravenously following heart transplantation. However, frequent administration can result in a substantial psychological burden to patients, resulting in non-adherence to medication. The purpose of our study is to overcome the disadvantages of systemic drug administration by developing a polymer-based delivery system that is tunable and biodegradable and that can release highly hydrophobic FK506 over extended periods to treat or prevent acute cardiac allograft rejection. Using an electrospinning method, long-acting microfibers were prepared, and FK506 appeared to be continuously released for up to 14 days based on the in vitro release profiles. After implanting the microfiber subcutaneously into the abdominals of transplanted rats, it was found that the infiltration of T cells and macrophages and the secretion of interleukin-2 (IL-2) and IL-1β were significantly reduced compared with those of the free FK506 groups. More importantly, the mean survival time (MST) of the PCL-FK506 group was significantly extended in comparison with that of untreated control recipients and free FK506 (MST of untreated control recipients, free FK506, and PCL-FK506 was 8, 26.1, and 37, respectively). In conclusion, we propose that this drug delivery approach would be suitable for developing long-lasting immunomodulatory agents that prolong cardiac graft survival safely and effectively.

Biphasic drug release from electrospun structures

INTRODUCTION

Biphasic release, as a special drug-modified release profile that combines immediate and sustained release, allows fast therapeutic action and retains blood drug concentration for long periods. Electrospun nanofibers, particularly those with complex nanostructures produced by multi-fluid electrospinning processes, are potential novel biphasic drug delivery systems (DDSs).

AREAS COVERED

This review summarizes the most recent developments in electrospinning and related structures. In this review, the role of electrospun nanostructures in biphasic drug release was comprehensively explored. These electrospun nanostructures include monolithic nanofibers obtained through single-fluid blending electrospinning, core-shell and Janus nanostructures prepared via bifluid electrospinning, three-compartment nanostructures obtained via trifluid electrospinning, nanofibrous assemblies obtained through the layer-by-layer deposition of nanofibers, and the combined structure of electrospun nanofiber mats with casting films. The strategies and mechanisms through which complex structures facilitate biphasic release were analyzed.

EXPERT OPINION

Electrospun structures can provide many strategies for the development of biphasic drug release DDSs. However, many issues such as the scale-up productions of complex nanostructures, the in vivo verification of the biphasic release effects, keeping pace with the developments of multi-fluid electrospinning, drawing support from the state-of-the-art pharmaceutical excipients, and the combination with traditional pharmaceutical methods need to be addressed for real applications.

Fast-Dissolving Nifedipine and Atorvastatin Calcium Electrospun Nanofibers as a Potential Buccal Delivery System

Geriatric patients are more likely to suffer from multiple chronic diseases that require using several drugs, which are commonly ingested. However, to enhance geriatric patients’ convenience, the electrospun nanofiber system was previously proven to be a successful alternative for the existing oral dosage forms, i.e., tablets and capsules. These nanofibers prepared either as single- or multi-layered fibers could hold at least one active compound in each layer. They might also be fabricated as ultra-disintegrated fibrous films for oral cavity administration, i.e., buccal or sublingual, to improve the bioavailability and intake of the administered drugs. Therefore, in this work, a combination of nifedipine and atorvastatin calcium, which are frequently prescribed for hypertension and hyperlipidemia patients, respectively, was prepared in a coaxial electrospinning system for buccal administration. Scanning electron microscopy image showed the successful preparation of smooth, non-beaded, and non-porous surfaces of the drug-loaded nanofibers with an average fiber diameter of 968 ± 198 nm. In contrast, transmission electron microscopy distinguished the inner and outer layers of those nanofibers. The disintegration of the drug-loaded nanofibers was ≤12 s, allowing the rapid release of nifedipine and atorvastatin calcium to 61% and 47%, respectively, after 10 min, while a complete drug release was achieved after 120 min. In vitro, a drug permeation study using Franz diffusion showed that the permeation of both drugs from the core–shell nanofibers was enhanced significantly (p < 0.05) compared to the drugs in a solution form. In conclusion, the development of drug-loaded nanofibers containing nifedipine and atorvastatin calcium can be a potential buccal delivery system.