Novel approach for overcoming the stability challenges of lipid-based excipients. Part 3: Application of polyglycerol esters of fatty acids for the next generation of solid lipid nanoparticles

Enhanced Skin Penetration and Efficacy: First and Second Generation Lipoidal Nanocarriers in Skin Cancer Therapy

Skin carcinoma remains one of the most widespread forms of cancer, and its global impact continues to increase. Basal cell carcinoma, melanoma, and squamous cell carcinoma are three kinds of cutaneous carcinomas depending upon occurrence and severity. The invasive nature of skin cancer, the limited effectiveness of current therapy techniques, and constraints to efficient systems for drug delivery are difficulties linked with the treatment of skin carcinoma. In the present era, the delivery of drugs has found a new and exciting horizon in the realm of nanotechnology, which presents inventive solutions to the problems posed by traditional therapeutic procedures for skin cancer management. Lipid-based nanocarriers like solid lipid nanoparticles and nanostructured lipid carriers have attracted a substantial focus in recent years owing to their capability to improve the drug's site-specific delivery, enhancing systemic availability, and thus its effectiveness. Due to their distinct structural and functional characteristics, these nanocarriers can deliver a range of medications, such as peptides, nucleic acids, and chemotherapeutics, via different biological barriers, such as the skin. In this review, an effort was made to present the mechanism of lipid nanocarrier permeation via cancerous skin. In addition, recent research advances in lipid nanocarriers have also been discussed with the help of in vitro cell lines and preclinical studies. Being a nano size, their limitations and toxicity aspects in living systems have also been elaborated.

Solid Lipid Nanoparticles Loaded with Dexamethasone Palmitate for Pulmonary Inflammation Treatment by Nebulization Approach

Pneumonia stands as the leading infectious cause of childhood mortality annually, underscoring its significant impact on pediatric health. Although dexamethasone (DXMS) is effective for treating pulmonary inflammation, its therapeutic potential is compromised by systemic side effects and suboptimal carrier systems. To address this issue, the current study introduces solid lipid nanoparticles encapsulating hydrophobic dexamethasone palmitate (DXMS-Pal-SLNs) as an anti-inflammatory nanoplatform to treat pneumonia. The specialized nanoparticle formulation is characterized by high drug loading efficiency, low drug leakage and excellent colloidal stability in particular during nebulization and is proficiently designed to target alveolar macrophages in deep lung regions via local delivery with the nebulization administration. In vitro analyses revealed substantial reductions in the secretions of tumor necrosis factor-α and interleukin-6 from alveolar macrophages, highlighting the potential efficacy of DXMS-Pal-SLNs in alleviating pneumonia-related inflammation. Similarly, in vivo experiments showed a significant reduction in the levels of these cytokines in the lungs of mice experiencing lipopolysaccharide-induced pulmonary inflammation after the administration of DXMS-Pal-SLNs via nebulization. Furthermore, the study demonstrated that DXMS-Pal-SLNs effectively control acute infections without causing pulmonary infiltration or excessive recruitment of immunocytes in lung tissues. These findings highlight the potential of nebulized DXMS-Pal-SLNs as a promising therapeutic strategy for mitigating pneumonia-related inflammations.

Novel Therapeutic Hybrid Systems Using Hydrogels and Nanotechnology: A Focus on Nanoemulgels for the Treatment of Skin Diseases

Topical and transdermal drug delivery are advantageous administration routes, especially when treating diseases and conditions with a skin etiology. Nevertheless, conventional dosage forms often lead to low therapeutic efficacy, safety issues, and patient noncompliance. To tackle these issues, novel topical and transdermal platforms involving nanotechnology have been developed. This review focuses on the latest advances regarding the development of nanoemulgels for skin application, encapsulating a wide variety of molecules, including already marketed drugs (miconazole, ketoconazole, fusidic acid, imiquimod, meloxicam), repurposed marketed drugs (atorvastatin, omeprazole, leflunomide), natural-derived compounds (eucalyptol, naringenin, thymoquinone, curcumin, chrysin, brucine, capsaicin), and other synthetic molecules (ebselen, tocotrienols, retinyl palmitate), for wound healing, skin and skin appendage infections, skin inflammatory diseases, skin cancer, neuropathy, or anti-aging purposes. Developed formulations revealed adequate droplet size, PDI, viscosity, spreadability, pH, stability, drug release, and drug permeation and/or retention capacity, having more advantageous characteristics than current marketed formulations. In vitro and/or in vivo studies established the safety and efficacy of the developed formulations, confirming their therapeutic potential, and making them promising platforms for the replacement of current therapies, or as possible adjuvant treatments, which might someday effectively reach the market to help fight highly incident skin or systemic diseases and conditions.

Future Nanotechnology-Based Strategies for Improved Management of Helicobacter pylori Infection

Helicobacter pylori (H. pylori) is a recalcitrant pathogen, which can cause gastric disorders. During the past decades, polypharmacy-based regimens, such as triple and quadruple therapies have been widely used against H. pylori. However, polyantibiotic therapies can disturb the host gastric/gut microbiota and lead to antibiotic resistance. Thus, simpler but more effective approaches should be developed. Here, some recent advances in nanostructured drug delivery systems to treat H. pylori infection are summarized. Also, for the first time, a drug release paradigm is proposed to prevent H. pylori antibiotic resistance along with an IVIVC model in order to connect the drug release profile with a reduction in bacterial colony counts. Then, local delivery systems including mucoadhesive, mucopenetrating, and cytoadhesive nanobiomaterials are discussed in the battle against H. pylori infection. Afterward, engineered delivery platforms including polymer-coated nanoemulsions and polymer-coated nanoliposomes are poposed. These bioinspired platforms can contain an antimicrobial agent enclosed within smart multifunctional nanoformulations. These bioplatforms can prevent the development of antibiotic resistance, as well as specifically killing H. pylori with no or only slight negative effects on the host gastrointestinal microbiota. Finally, the essential checkpoints that should be passed to confirm the potential effectiveness of anti-H. pylori nanosystems are discussed.

Lipid-based particle engineering via spray-drying for targeted delivery of antibiotics to the lung

Pulmonary delivery of antibiotics for the treatment of tuberculosis provides several benefits compared to conventional oral and parenteral administration. API-loaded particles delivered directly to alveolar macrophages, where Mycobacterium tuberculosis resides, can reduce the required dose and decrease the severe side effects of conventional treatment. In this work, lipid-microparticles loaded with rifampicin were engineered via spray-drying to be administered as a carrier-free dry powder for inhalation. Although, it is well-known that spray-drying of lipid-based excipients is strongly limited, a completely lipid-based formulation using diglycerol full ester of behenic acid was produced. The solid state of the lipid, providing high melting temperature, absence of polymorphism and monophasic crystallization, led to high yield of spray-dried particles (83%). Inhalable particles of mass median aerodynamic diameter of 2.36 µm, median geometric size of 2.05 µm, and negative surface (-50.03 mV) were engineered. Such attributes were defined for deep lung deposition and targeted delivery of antibiotics to alveolar macrophages. Superior aerodynamic performance as carrier-free DPI was associated to a high fine particle fraction of 79.5 %. No in vitro cytotoxic effects were found after exposing epithelial cell lines and alveolar macrophages. In vitro uptake of particles into alveolar macrophages indicated the efficiency of their targeted delivery. The use of highly processable and safe lipid-based excipients for particle engineering via spray-drying can extend the availability of materials for functionalized applications for pulmonary delivery.

Inhaled lipid nanocarriers for pulmonary delivery of glucocorticoids: previous strategies, recent advances and key factors description

In view of the strong anti-inflammatory activity of glucocorticoids (GC) they are used in the treatment of almost all inflammatory lung diseases. In particular, inhaled GC (IGC) allow high drug concentrations to be deposited in the lung and may reduce the incidence of adverse effects associated with systemic administration. However, rapid absorption through the highly absorbent surface of the lung epithelium may limit the success of localized therapy. Therefore, inhalation of GC incorporated into nanocarriers is a possible approach to overcome this drawback. In particular, lipid nanocarriers, which showed high pulmonary biocompatibility and are well known in the pharmaceutical industry, have the best prospects for pulmonary delivery of GC by inhalation. This review provides an overview of the pre-clinical applications of inhaled GC-lipid nanocarriers based on several key factors that will determine the efficiency of local pulmonary GC delivery: 1) stability to nebulization, 2) deposition profile in the lungs, 3) mucociliary clearance, 4) selective accumulation in target cells, 5) residence time in the lung and systemic absorption and 6) biocompatibility. Finally, novel preclinical pulmonary models for inflammatory lung diseases are also discussed.

Lipid-microparticles for pulmonary delivery of active pharmaceutical ingredients: Impact of lipid crystallization on spray-drying processability

Spray-drying is an extensively used technology for engineering inhalable particles. Important technical hurdles are however experienced when lipid-based excipients (LBEs) are spray-dried. Stickiness, extensive wall deposition, or simply inability to yield a solid product have been associated to the low melting points of LBEs. In this work, solutions containing polyglycerol esters of behenic acid (PGFA-behenates), or other high melting point LBEs, were spray-dried to produce ibuprofen (IBU)-loaded inhalable lipid-microparticles. Prior to spray-drying, rational boundaries for the outlet temperature of the process were defined using LBE-IBU phase diagrams. Despite spray-drying the solutions at outlet temperatures below the boundaries, process performance and yield among LBEs were entirely different. Lipid crystallization into polymorphs or multi-phases negatively impacted the yield (10-47%), associated to liquid fractions unable to recrystallize at the surrounding gas temperature in the spray-dryer. The highest yields (76-82%), ascribed to PGFA-behenates, resulted from monophasic crystallization and absence of polymorphism. Lipid-microparticles, composed of a PGFA-behenate, were characterized by a volume mean diameter of 6.586 µm, tap density of 0.389 g/cm³ and corrugated surface. Application as carrier-free dry powder for inhalation resulted in high emitted fraction (90.9%), median mass aerodynamic diameter of 3.568 µm, fine particle fraction of 45.6% and modified release in simulated lung fluid.

Nanoparticle-Based Drug Delivery System: The Magic Bullet for the Treatment of Chronic Pulmonary Diseases

Chronic pulmonary diseases encompass different persistent and lethal diseases, including chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), cystic fibrosis (CF), asthma, and lung cancers that affect millions of people globally. Traditional pharmacotherapeutic treatment approaches (i.e., bronchodilators, corticosteroids, chemotherapeutics, peptide-based agents, etc.) are not satisfactory to cure or impede diseases. With the advent of nanotechnology, drug delivery to an intended site is still difficult, but the nanoparticle's physicochemical properties can accomplish targeted therapeutic delivery. Based on their surface, size, density, and physical-chemical properties, nanoparticles have demonstrated enhanced pharmacokinetics of actives, achieving the spotlight in the drug delivery research field. In this review, the authors have highlighted different nanoparticle-based therapeutic delivery approaches to treat chronic pulmonary diseases along with the preparation techniques. The authors have remarked the nanosuspension delivery via nebulization and dry powder carrier is further effective in the lung delivery system since the particles released from these systems are innumerable to composite nanoparticles. The authors have also outlined the inhaled particle's toxicity, patented nanoparticle-based pulmonary formulations, and commercial pulmonary drug delivery devices (PDD) in other sections. Recently advanced formulations employing nanoparticles as therapeutic carriers for the efficient treatment of chronic pulmonary diseases are also canvassed.

Pessaries containing nanostructured lipid carriers (NLC) for prolonged vaginal delivery of progesterone

Progesterone (PRG) plays a crucial role in the female reproductive system, being the vaginal route the most adequate for its administration, as this drug has an extensive hepatic first pass effect. Nonetheless, vaginal PRG dosage forms originate immediate drug release and requires repeated administrations, which is unpleasant. Thereby, it is necessary to develop alternative delivery systems for prolonged vaginal release of PRG. The objective of this work was the development of pessaries for the prolonged vaginal delivery of PRG. Studies began with the preparation of an aqueous dispersion of PRG-loaded NLC (NLC_PRG), followed by the evaluation of its biocompatibility in human immortalized keratinocytes (HaCat cells), using three different methods (neutral red uptake, resazurin reduction and sulforhodamine B assays). Finally, the NLC_PRG was incorporated into pessaries, which were further characterized according to the European Pharmacopoeia to assess their suitability to prolong PRG release through the vaginal route. The results showed that, after preparation, 90% of the NLC_PRG had sizes equal or lower than 315.60 ± 0.01 nm, and an EE of 96.42 ± 0.00%. All the assays used to assess the biocompatibility of NLC_PRG showed the absence of cytotoxicity towards HaCaT cells for concentrations up to 10 μg/mL. In all cytotoxicity assays, a cytotoxic effect was only observed for concentrations equal or higher than 25 μg/mL, which provides high confidence in the obtained results. The outcomes of this study suggest the suitability of using pessaries containing PRG-loaded NLC for sustained drug release, which is an innovative therapeutic strategy and constitutes a promising alternative for the vaginal use of PRG. However, further ex vivo and in vivo studies are needed to fully clarify the pharmacokinetic and toxicological profile before reaching the clinical use.