Immunomodulatory Effect of Novel Electrospun Nanofibers Loaded with Doxycycline as an Adjuvant Treatment in Periodontitis

Impact of polycaprolactone, alginate, chitosan and zein nanofiber physical properties on immune cells for safe biomedical applications

Nanofiber safety, especially immunogenicity, is important for their successful translation to clinical setting. This study provides a comprehensive evaluation of how nanofiber physical properties influence immune cells cultured on them, specifically peripheral blood mononuclear cells (PBMCs). We prepared nanofibers with a wide range of physical properties including various diameters, interfibrillar pore sizes and mat thicknesses, using four main polymers: polycaprolactone, alginate, chitosan, and zein. Our findings show that nanofiber diameters had only a marginal influence on the activity of immune cells, whereas interfibrillar nanofiber pore sizes had a significant effect, and mat thickness proved to have the greatest impact. Cells that penetrated deeper into the thick nanofiber mats ceased to proliferate but did not experience cytotoxicity. Moreover, we discovered that PBMCs penetrating the zein/PVP nanofiber mesh exhibited increased metabolic activity, indicating potential immunogenicity, whereas the other tested non-immunogenic nanofibers reduced it. To best of our knowledge, this study is the first to report on the impact of various nanofiber physical properties on in vitro immune cell behavior, thereby expanding the knowledge in the relatively unexplored field of nanofiber immunological safety. It underscores the need for rigorous preclinical nanofiber assessment and setting new standards for designing nanofiber-based biomedical products.

Local Drug Delivery Systems as Novel Approach for Controlling NETosis in Periodontitis

Periodontitis is a chronic inflammation caused by periodontopathogenic bacteria in the dental biofilm, and also involves the inflammatory-immune response of the host. Polymorphonuclear neutrophils (PMNs) play essential roles in bacterial clearance by multiple mechanisms, including the formation of neutrophil extracellular traps (NETs) that retain and destroy pathogens. During PD progression, the interaction between PMNs, NETs, and bacteria leads to an exaggerated immune response and a prolonged inflammatory state. As a lesion matures, PMNs accumulate in the periodontal tissues and die via NETosis, ultimately resulting in tissue injury. A better understanding of the role of NETs, the associated molecules, and the pathogenic pathways of NET formation in periodontitis, could provide markers of NETosis as reliable diagnostic and prognostic tools. Moreover, an assessment of NET biomarker levels in biofluids, particularly in saliva or gingival crevicular fluid, could be useful for monitoring periodontitis progression and treatment efficacy. Preventing excessive NET accumulation in periodontal tissues, by both controlling NETs' formation and their appropriate removal, could be a key for further development of more efficient therapeutic approaches. In periodontal therapy, local drug delivery (LDD) systems are more targeted, enhancing the bioavailability of active pharmacological agents in the periodontal pocket and surrounding tissues for prolonged time to ensure an optimal therapeutic outcome.

Nanodrug Delivery Systems for Myasthenia Gravis: Advances and Perspectives

Myasthenia gravis (MG) is a rare chronic autoimmune disease caused by the production of autoantibodies against the postsynaptic membrane receptors present at the neuromuscular junction. This condition is characterized by fatigue and muscle weakness, including diplopia, ptosis, and systemic impairment. Emerging evidence suggests that in addition to immune dysregulation, the pathogenesis of MG may involve mitochondrial damage and ferroptosis. Mitochondria are the primary site of energy production, and the reactive oxygen species (ROS) generated due to mitochondrial dysfunction can induce ferroptosis. Nanomedicines have been extensively employed to treat various disorders due to their modifiability and good biocompatibility, but their application in MG management has been rather limited. Nevertheless, nanodrug delivery systems that carry immunomodulatory agents, anti-oxidants, or ferroptosis inhibitors could be effective for the treatment of MG. Therefore, this review focuses on various nanoplatforms aimed at attenuating immune dysregulation, restoring mitochondrial function, and inhibiting ferroptosis that could potentially serve as promising agents for targeted MG therapy.

Electrospun nanofibers applications in caries lesions: prevention, treatment and regeneration

Dental caries is a multifactorial disease primarily mediated by biofilm formation, resulting in a net loss of mineral content and degradation of organic matrix in dental hard tissues. Caries lesions of varying depths can result in demineralization of the superficial enamel, the formation of deep cavities extending into the dentin, and even pulp infection. Electrospun nanofibers (ESNs) exhibit an expansive specific surface area and a porous structure, closely mimicking the unique architecture of the natural extracellular matrix (ECM). This unique topography caters to the transport of small molecules and facilitates localized therapeutic drug delivery, offering great potential in regulating cell behavior, and thereby attracting interest in ESNs' applications in the treatment of caries lesions and the reconditioning of the affected dental tissues. Thus, this review aims to consolidate the recent developments in ESNs' applications for caries lesions. This review begins with an introduction to the electrospinning technique and provides a comprehensive overview of the biological properties and modification methods of ESNs, followed by an introduction outlining the basic pathological processes, classification and treatment requirements of caries lesions. Finally, the review offers a detailed examination of the research progress on the ESNs' application in caries lesions and concludes by addressing the limitations.

QbD-Assisted Development and Optimization of Doxycycline Hyclate- and Hydroxyapatite-Loaded Nanoparticles for Periodontal Delivery

The current research aims to develop a carrier system for the delivery of a matrix metalloproteinase (MMP) inhibitor along with a bioceramic agent to the periodontal pocket. It is proposed that the present system, if given along with a systemic antibiotic, would be a fruitful approach for periodontitis amelioration. To fulfill the aforementioned objective, a doxycycline hyclate- and hydroxyapatite-adsorbed composite was prepared by a physical adsorption method and successfully loaded inside sodium alginate-chitosan nanoparticles and optimized based on particle size and drug content. Optimized formulation was then subjected to different evaluation parameters like encapsulation efficiency, hydroxyapatite content, ζ potential, surface morphology, in vitro drug release, cell line studies, and stability studies. For the optimized formulation, particle size, polydispersity index (PDI), entrapment efficiency, ζ potential, and drug content were found to be 336.50 nm, 0.23, 41.77%, -13.85 mV, and 14.00%, respectively. The surface morphology of the placebo and adsorbed composite-loaded nanoparticles as observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed the spherical shape and rough surface of the particles. In gingival crevicular fluid (GCF) 7.6, a sustained drug release profile was obtained up to 36 h. In vitro % viability studies performed on murine fibroblast cells (NIH3T3) and human periodontal ligament (hPDL) cell lines confirmed the proliferative nature of the formulation. Also, when subjected to stability studies for 4 weeks, particle size, PDI, and drug content did not vary considerably, thereby ensuring the stable nature of nanoparticles. Henceforth, sodium alginate-chitosan nanoparticles appeared to be a good carrier system for doxycycline hyclate and hydroxyapatite for periodontal therapy. If given along with a system antibiotic, the system will serve as a fruitful tool for infection-mediated periodontal regeneration and healing.

Biomaterials Functionalized with Inflammasome Inhibitors-Premises and Perspectives

This review aimed at searching literature for data regarding the inflammasomes' involvement in the pathogenesis of oral diseases (mainly periodontitis) and general pathologies, including approaches to control inflammasome-related pathogenic mechanisms. The inflammasomes are part of the innate immune response that activates inflammatory caspases by canonical and noncanonical pathways, to control the activity of Gasdermin D. Once an inflammasome is activated, pro-inflammatory cytokines, such as interleukins, are released. Thus, inflammasomes are involved in inflammatory, autoimmune and autoinflammatory diseases. The review also investigated novel therapies based on the use of phytochemicals and pharmaceutical substances for inhibiting inflammasome activity. Pharmaceutical substances can control the inflammasomes by three mechanisms: inhibiting the intracellular signaling pathways (Allopurinol and SS-31), blocking inflammasome components (VX-765, Emricasan and VX-740), and inhibiting cytokines mediated by the inflammasomes (Canakinumab, Anakinra and Rilonacept). Moreover, phytochemicals inhibit the inflammasomes by neutralizing reactive oxygen species. Biomaterials functionalized by the adsorption of therapeutic agents onto different nanomaterials could represent future research directions to facilitate multimodal and sequential treatment in oral pathologies.

Are Local Drug Delivery Systems a Challenge in Clinical Periodontology?

Placing antimicrobial treatments directly in periodontal pockets is an example of the local administration of antimicrobial drugs to treat periodontitis. This method of therapy is advantageous since the drug concentration after application far surpasses the minimum inhibitory concentration (MIC) and lasts for a number of weeks. As a result, numerous local drug delivery systems (LDDSs) utilizing various antibiotics or antiseptics have been created. There is constant effort to develop novel formulations for the localized administration of periodontitis treatments, some of which have failed to show any efficacy while others show promise. Thus, future research should focus on the way LDDSs can be personalized in order to optimize future clinical protocols in periodontal therapy.