Lyophilized Hybrid Nanostructured Lipid Carriers to Enhance the Cellular Uptake of Verapamil: Statistical Optimization and In Vitro Evaluation

Augmented silver sulfadiazine nanostructured lipid carriers impregnated collagen sponge for promoting burn wound healing

Silver sulfadiazine (SSD) is a widely used antibacterial agent for burn wound treatment owing to its capability in re-epithelialization and wound healing. However, due to its low solubility, the need for an effective drug delivery system is mandatory. This study aimed to optimize SSD nanostructured lipid-based carriers (NLCs), incorporated in a collagen sponge form as an innovative topical dosage form for effective burn wound treatment. SSD-NLCs were prepared by applying Box-Behnken design and characterized in terms of particle size, zeta potential, and entrapment efficiency (EE). The optimized SSD-NLCs formula was selected and incorporated into a cross-linked collagen sponge and lyophilized for 24 h. The SSD-NLCs sponge morphological structure, porosity, swelling ratio, in vitro drug release profile and antibacterial activity were assessed. Furthermore, investigating the competitive inhibitory efficiency of SSD against para-aminobenzoic acid (PABA), the native ligand for the dihydropteroate synthetase enzyme based on the calculated binding free energy using the CB-Dock docking server was evaluated. Additionally, the wound healing activity and histopathological studies were evaluated on a second-degree burn wounds in a rat model. The optimized SSD-NLCs were spherical, possessing size of 115.69 ± 3.25 nm, EE% of 89.69 ± 1.36 % and a porosity of 71.22 %. Furthermore, the SSD-NLCs sponge showed an enhanced swelling ratio and improved antimicrobial activity compared to SSD. Finally, in vivo studies in rats showed that SSD-NLCs sponge are effective wound healing formulation owing to their ability to improve the quality of tissue regeneration without scars formation. Results showed that SSD-NLCs sponge can enhance the SSD efficacy in treatment of burn wounds. Further toxicological studies are still needed before clinical application.

Multifunctional hyaluronic acid-based biomimetic/pH-responsive hybrid nanostructured lipid carriers for treating bacterial sepsis

INTRODUCTION

The application of biomimetic and stimuli-responsive nanocarriers displays considerable promise in improving the management of bacterial sepsis and overcoming antimicrobial resistance. Therefore, the study aimed to synthesize a novel hyaluronic acid-lysine conjugate (HA-Lys) and to utilize the attributes of the synthesized HA-Lys with Tocopherol succinate (TS) and Oleylamine (OLA) in the formulation of multifunctional biomimetic pH-responsive HNLCs loaded with vancomycin (VCM-HNLCs), to combat bacterial sepsis.

METHODS

A novel hyaluronic acid-lysine conjugate (HA-Lys) was synthesized and characterized using FTIR and 1H NMR spectroscopy. Vancomycin-loaded hybrid nanosystems (VCM-HNLCs) were prepared through hot homogenization ultrasonication and evaluated for particle size, polydispersity index (PDI), zeta potential (ZP), and encapsulation efficiency (EE%). In vitro biocompatibility was assessed via MTT assay and red blood cell hemolysis test. The binding affinity to TLR2 and TLR4 was measured using microscale thermophoresis (MST). Drug release was evaluated using the dialysis bag method. Antimicrobial activity against MRSA and efflux pump inhibition were also determined. Efficacy was demonstrated in an MRSA-induced sepsis mice model.

RESULTS

The VCM-HNLCs, produced via hot homogenization ultrasonication, exhibited particle size (PS), polydispersity index (PDI), zeta potential (ZP), and encapsulation efficiency (EE%) of 110.77 ± 1.692 nm, 0.113 ± 0.022, - 2.92 ± 0.210 mV, and 76.27 ± 1.200%, respectively. In vitro, biocompatibility was proven by hemolysis and cytotoxicity studies. The VCM-HNLCs demonstrated targetability to human Toll-like receptors (TLR 2 and 4) as validated by microscale thermophoresis (MST). VCM-HNLCs showed a twofold reduction in MIC values at physiological pH compared to the bare VCM against S. aureus and MRSA for 48 h. While at pH 6.0, MIC values were reduced by fourfold in the first 24 h and by eightfold in the subsequent 48 and 72 h against tested strains. Furthermore, VCM-HNLCs showed inhibitory effects against MRSA efflux pumps, reactive oxygen species (ROS), and lipopolysaccharide (LPS)-induced hyperinflammation. In an MRSA-induced sepsis mice model, VCM-HNLCs demonstrated superior efficacy compared to free VCM, significantly eliminated bacteria and improved survival rates.

CONCLUSIONS

Overall, these results highlight the potential of VCM-HNLCs as novel multifunctional nanocarriers to combat antimicrobial resistance (AMR) and enhance sepsis outcomes.

Design of solid lipid nanoparticles for skin photoprotection through the topical delivery of caffeic acid-phthalimide

Exposure of the skin to ultraviolet (UV) radiation is associated with many pathological conditions such as premature aging and skin cancer. Furthermore, members of Nicotinamide Adenine Dinucleotide Phosphate-oxidase (NADPH oxidase or NOX) enzyme family can produce UV-induced reactive oxygen species (ROS), even after cessation of radiation exposure. The caffeic acid-phthalimide (CF) compound is a potent antioxidant, which reduces the generation of ROS. However, its high lipophilicity may hamper its permeation through the skin. Solid lipid nanoparticles (SLNs) can ensure close contact and increase the amount of drug absorbed into the skin. The present work aims to develop and optimize SLNs containing CF to achieve enhanced skin photoprotection along with antioxidant and anti-aging effects. SLNs were prepared by the hot homogenization method using Compritol 888 ATO as lipid matrix, and Tween 80 and Pluronic® F-127 as surfactants to stabilize the nanoparticle dispersion. The particles had high stability for at least 30 days. Physicochemical characterizations of the selected SLNs formulations showed sizes in the range 150-180 nm, polydispersity index (PDI) of 0.2, and a negative zeta potential (≅ -25  mV). The SLNs had high CF entrapment efficiency (96-97 %) and showed a controlled drug-release profile. The in vitro study revealed low cytotoxic properties of CF-loaded SLNs towards fibroblasts and a photoprotective effect, reflected from the increased viability of UVB-irradiated fibroblasts treated with CF-SLNs. Moreover, the CF-SLNs induced fibroblast migration and closure, showing that these nanosystems offer not only biological photoprotection, but also stimulate wound healing.

Intranasal delivery of sulpiride nanostructured lipid carrier to central nervous system; in vitro characterization and in vivo study

The low and erratic oral absorption of sulpiride (SUL) a dopaminergic receptor antagonist, and its P-glycoprotein efflux in the gastrointestinal tract restricted its oral route for central nervous system disorders. An intranasal formulation was formulated based on nanostructured lipid carrier to tackle these obstacles and deliver SUL directly to the brain. Sulipride-loaded nanostructured lipid carrier (SUL-NLC) was prepared using compritol®888 ATO and different types of liquid lipids and emulsifiers. SUL-NLCs were characterized for their particle size, charge, and encapsulation efficiency. Morphology and compatibility with other NLC excipients were also studied. Moreover, SUL in vitro release, nanodispersion stability, in vivo performance and SUL pharmacokinetics were investigated. Results delineates that SUL-NLC have a particle size ranging from 366.2 ± 62.1 to 640.4 ± 50.2 nm and encapsulation efficiency of 75.5 ± 1.5%. SUL showed a sustained release pattern over 24 h and maintained its physical stability for three months. Intranasal SUL-NLC showed a significantly (p < 0.01) higher SUL brain concentration than that found in plasma after oral administration of commercial SUL product with 4.47-fold increase in the relative bioavailability. SUL-NLCs as a nose to brain approach is a promising formulation for enhancing the SUL bioavailability and efficient management of neurological disorders.

Antitumoral melatonin-loaded nanostructured lipid carriers

Aim: Cancer constitutes the second leading cause of death worldwide, with conventional therapies limited by significant side effects. Melatonin (MEL), a natural compound with antitumoral properties, suffers from instability and low solubility. To overcome these issues, MEL was encapsulated into nanostructured lipid carriers (MEL-NLC) containing rosehip oil to enhance stability and boost its antitumoral activity.Methods: MEL-NLC were optimized by a design of experiments approach and characterized for their physicochemical properties. Stability and biopharmaceutical behavior were assessed, along with interaction studies and in vitro antitumoral efficacy against various cancer cell lines.Results: Optimized MEL-NLC exhibited desirable physicochemical characteristics, including small particle size and sustained MEL release, along with long-term stability. In vitro studies demonstrated that MEL-NLC selectively induced cytotoxicity in several cancer cell lines while sparing healthy cells.Conclusion: MEL-NLC represent a promising alternative for cancer, combining enhanced stability and targeted antitumoral activity, potentially overcoming the limitations of conventional treatments.

Bio-evaluations of sericin coated hesperidin nanoparticles for gastric ulcer management

Gastric ulcers are worrying, and their worsening conditions may result in bleeding in the internal lining of the stomach. The problem is annoying, and both patients and professionals are still not satisfied with the available treatment options. Hesperidin, a flavonoid molecule with potent anti-inflammatory and antioxidant effects, can work like witchcraft to repair gastric ulcers and preserve the stomach lining. Here, we employed a strategy that involved covering the surface of the nano-lipid carriers (NLCs) with sericin before encasing the hesperidin within (Se-He-NLC). Sericin, a biodegradable polymer increases the muco-adhesion with stomach lining and deployment of hesperidin in controlled manner. Se-He-NLCs were physico-chemically characterized for drug loading, encapsulation, particle size, morphology, drug release, chemical stability, and chemical bonding. The nanocarriers showed first order drug release in a controlled manner. Se-He-NLCs showed better in vitro permeation and ex vivo mucoadhesion, thereby by promoting the in vivo bioavailability. Se-He-NLCs also promoted the reduced glutathione (GSH) and glutathione-S-transferase (GST) levels by 2.24- and 1.61-folds, respectively in the stomach lining, and also the regulation of superoxide dismutase (SOD) and catalase (CAT) activities parallel to the control group. In addition, tissues lipid hydroperoxides (LOOH) and myeloperoxidase (MPO) activity were reduced significantly with Se-He-NLCs administration. Se-He-NLC therapy of stomach ulcers in vivo demonstrated better binding ratio and ulcer healing potential. This approach reveals huge capacity for delivering therapies to treat gastric ulcers based on the clinical significance of sericin coated hesperidin nanocarriers in gastric ulcer treatment.

Targeted DPPC/DMPG surface-modified voriconazole lipid nanoparticles control invasive pulmonary aspergillosis in immunocompromised population: in-vitro and in-vivo assessment

Invasive pulmonary aspergillosis (IPA) is the most devastating Aspergillus-related lung disease. Voriconazole (VRZ) is the first-line treatment against IPA. Despite availability in oral and parenteral dosage forms, risks of systemic toxicity dictate alternative pulmonary administration. Inspired by natural lung surfactants, dipalmitoylphosphatidylcholine/dimyristoylphosphatidylglycerol (DPPC/DMPG) surface-modified lipid nanoparticles (LNPs) were scrutinized for pulmonary administration. DPPC/DMPG-VRZ-LNPs prepared using ultrasonication/thin film hydration were investigated for colloidal properties over 3-month shelf storage. They were stable with a slight change in entrapment efficiency. They provided a sustained VRZ release over 24 h, with a rapid initial release. In vitro aerosolization indicated higher percentages of VRZ deposited on stages corresponding to secondary bronchi and alveolar ducts. Moreover, intrapulmonary administration maintained high lung VRZ concentration (27 ± 1.14 µg/g) after 6 h. A preclinical study using a cyclophosphamide-induced neutropenic rat model demonstrated a 3-fold reduction in BALF-Galactomannan down to 0.515 ± 0.22 µg/L confirming DPPC/DMPG-VRZ-LNPs potential in hyphal growth inhibition. Histopathological examination of infected/nontreated lung sections exhibited dense fungal load inside alveoli and blood vessels indicating massive tissue and angio-invasiveness. Nevertheless, DPPC/DMPG-VRZ-LNPs-treated animals displayed minimal hyphae with no signs of invasiveness. The developed bioinspired nanoparticles serve as prospective bioactive nanocarrier candidates for pulmonary administration of VRZ in the management of IPA.

Dually Active Apigenin-Loaded Nanostructured Lipid Carriers for Cancer Treatment

Purpose

Cancer is one of the major causes of death worldwide affecting more than 19 million people. Traditional cancer therapies have many adverse effects and often result in unsatisfactory outcomes. Natural flavones, such as apigenin (APG), have demonstrated excellent antitumoral properties. However, they have a low aqueous solubility. To overcome this drawback, APG can be encapsulated in nanostructured lipid carriers (NLC). Therefore, we developed dual NLC encapsulating APG (APG-NLC) with a lipid matrix containing rosehip oil, which is known for its anti-inflammatory and antioxidant properties.

Methods

Optimisation, physicochemical characterisation, biopharmaceutical behaviour, and therapeutic efficacy of this novel nanostructured system were assessed.

Results

APG-NLC were optimized obtaining an average particle size below 200 nm, a surface charge of -20 mV, and an encapsulation efficiency over 99%. The APG-NLC released APG in a sustained manner, and the results showed that the formulation was stable for more than 10 months. In vitro studies showed that APG-NLC possess significant antiangiogenic activity in ovo and selective antiproliferative activity in several cancer cell lines without exhibiting toxicity in healthy cells.

Conclusion

APG-NLC containing rosehip oil were optimised. They exhibit suitable physicochemical parameters, storage stability for more than 10 months, and prolonged APG release. Moreover, APG-NLC were internalised inside tumour cells, showing the capacity to cause cytotoxicity in cancer cells without damaging healthy cells.

In vitro-in vivo assessments of apocynin-hybrid nanoparticle-based gel as an effective nanophytomedicine for treatment of rheumatoid arthritis

Apocynin (APO), a well-known bioactive plant-based phenolic phytochemical with renowned anti-inflammatory and antioxidant pharmacological activities, has recently emerged as a specific nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) oxidase inhibitor. As far as we know, no information has been issued yet regarding its topical application as a nanostructured-based delivery system. Herein, APO-loaded Compritol® 888 ATO (lipid)/chitosan (polymer) hybrid nanoparticles (APO-loaded CPT/CS hybrid NPs) were successfully developed, characterized, and optimized, adopting a fully randomized design (32) with two independent active parameters (IAPs), namely, CPT amount (XA) and Pluronic® F-68 (PF-68) concentration (XB), at three levels. Further in vitro-ex vivo investigation of the optimized formulation was performed before its incorporation into a gel base matrix to prolong its residence time with consequent therapeutic efficacy enhancement. Subsequently, scrupulous ex vivo-in vivo evaluations of APO-hybrid NPs-based gel (containing the optimized formulation) to scout out its momentous activity as a topical nanostructured system for beneficial remedy of rheumatoid arthritis (RA) were performed. Imperatively, the results support an anticipated effectual therapeutic activity of the APO-hybrid NPs-based gel formulation against Complete Freund's Adjuvant-induced rheumatoid arthritis (CFA-induced RA) in rats. In conclusion, APO-hybrid NPs-based gel could be considered a promising topical nanostructured system to break new ground for phytopharmaceutical medical involvement in inflammatory-dependent ailments.

Chondroitin/Lactoferrin-dual functionalized pterostilbene-solid lipid nanoparticles as targeted breast cancer therapy

Breast cancer remains the leading cause of cancer-associated mortality in women. Research investigating novel therapeutic approaches is thus crucial, including phytotherapeutics. Pterostilbene (PTS) is a phytochemical agent with promising efficacy against breast cancer. Poor solubility, low bioavailability and chemical instability are major drawbacks compromising PTS functionality. Herein, novel PTS-loaded solid lipid nanoparticles (PTS-SLNs) were fabricated using the ultrasonication technique. Dual-functionalization with lactoferrin (Lf) and chondroitin-sulfate (CS; CS/Lf/PTS-SLNs) was adopted as active-targeting approach. CS/Lf/PTS-SLNs demonstrated nanoparticle-size (223.42 ± 18.71 nm), low PDI (0.33 ± 0.017), acceptable zeta potential (-11.85 ± 0.07 mV) and controlled release (72.93 ± 2.93% after 24 h). In vitro studies on triple-negative MDA-MB-231 revealed prominent cytotoxicity of CS/Lf/PTS-SLNs (2.63-fold IC50 reduction), higher anti-migratory effect and cellular uptake relative to PTS-solution. The in vivo anti-tumor efficacy in an orthotopic cancer model verified the superiority of CS/Lf/PTS-SLNs; achieving 2.4-fold decrease in tumor growth compared to PTS-solution. On the molecular level, CS/Lf/PTS-SLNs enhanced suppression of VEGF, down-regulated cyclin D1 and upregulated caspase-3 and BAX, compared to PTS-solution. Also, immunohistochemical assay confirmed the higher anti-tumorigenic effect of CS/Lf/PTS-SLNs (5.87-fold decrease in Bcl-2 expression) compared to PTS-solution. Our findings highlight CS/Lf/PTS-SLNs as a promising nanoplatform for phytotherapeutic targeted-breast cancer therapy.

Multicomponent Antibiofilm Lipid Nanoparticles as Novel Platform to Ameliorate Resveratrol Properties: Preliminary Outcomes on Fibroblast Proliferation and Migration

The well-being of skin and mucous membranes is fundamental for the homeostasis of the body and thus it is imperative to treat any lesion quickly and correctly. In this view, polyphenols might assist and enhance a successful wound healing process by reducing the inflammatory cascade and the production of free radicals. However, they suffer from disadvantageous physico-chemical properties, leading to restricted clinical use. In this work, a complex mixture of PEGylated lipid, Glyceryl monoester, 18-β-Glycyrrhetinic Acid and Menthol was designed to entrap Resveratrol (RSV) as the active ingredient and further produce lipid nanoparticles (LNPs) by homogenization followed by high-frequency sonication. The nanosystem was properly characterized in terms of particle size (DLS, SEM), zeta potential, drug loading, antioxidant power (DPPH), release behaviour, cytocompatibility, wound healing and antibiofilm properties. The optimized lipid mixture was homogeneous, melted at 57-61 °C and encapsulated amorphous RSV (4.56 ± 0.04% w/w). The RSV-loaded LNPs were almost monodispersed (PDI: 0.267 ± 0.010), with nanometric size (162.86 ± 3.12 nm), scavenger properties and suitable DR% and LE% values (96.82 ± 1.34% and 95.17 ± 0.25%, respectively). The release studies were performed to simulate the wound conditions: 1-octanol to mimic the lipophilic domains of biological tissues (where the First Order kinetic was observed) and citrate buffer pH 5.5 according to the inflammatory wound exudate (where the Korsmeyer-Peppas kinetic was followed). The biological and microbiological evaluations highlighted fibroblast proliferation and migration effects as well as antibiofilm properties at extremely low doses (LNPs: 22 μg/mL, corresponding to RSV 5 µM). Thus, the proposed multicomponent LNPs could represent a valuable RSV delivery platform for wound healing purposes.

In vitro bio-characterization of solid lipid nanoparticles of favipiravir in A549 human lung epithelial cancer cells

Objectives

Lung cancer is a leading cause of mortality worldwide. In lung cancer treatment, nebulized solid lipid nanoparticles may be a viable drug delivery method, helping the drug reach sites of action, and improving its inhalation efficiency and pulmonary deposition. This research focused on evaluating the effectiveness of solid lipid nanoparticles of favipiravir (Fav-SLNps) in facilitating drug delivery to sites of action in lung cancer treatment.

Methods

The hot-evaporation method was used to formulate Fav-SLNps. The in vitro cell viability, anti-cancer effects, and cellular uptake activity were evaluated in A549 human lung adenocarcinoma cells treated with the Fav-SLNp formulation.

Results

The Fav-SLNps were formulated successfully. Importantly, Fav-SLNps at a concentration of 322.6 μg/ml were found to be safe and non-toxic toward A549 cells in vitro. The formulation had potential anti-proliferative properties via increasing the proportions of cells in G2/M and G0/G1 phases to 1.20 and 1.13 times those in untreated cells. Additionally, Fav-SLNp treatment significantly induced necrosis in A549 cells. Furthermore, the use of SLNps in the Fav formulation resulted in a macrophage drug uptake 1.23 times that of the free drug.

Conclusion

Our results confirmed the internalization and anti-cancer activity of the Fav-SLNp formulation in the A549 lung cancer cell line. Our findings suggest that Fav-SLNps could potentially be used as lung cancer treatment to facilitate drug delivery to sites of action in the lungs.

Nanostructured Lipid Carriers for Oral Delivery of a Corticosteroid: Role of Formulation on Biopharmaceutical Performance

Corticosteroids are potent anti-inflammatory and immunosuppressive drugs widely used world-wide for treatment of diverse conditions. However, their use is restricted by their poor bioavailability and high risk-benefit ratio. Therefore, the aim of this study was to develop nanostructred lipid carriers (NLC) of prednisolone acetate (PA) to improve the drug's therapeutic outcome by altering its pharmacokinetic profile and/or allow preferential targeting to inflammatory tissues. PA-loaded NLCs were formulated by solvent injection method using Compritol (solid lipid), oleic acid (liquid lipid) and Tween 80 or Pluronic F68 (surfactant). Formulation conditions, such as liquid lipid concentration, total lipids, drug:lipid ratio and surfactant type were optimized based on particle size (PS), polydispersity index (PDI), and encapsulation efficiency (EE%) results. Optimized formulation was further characterized for its surface morphology, thermal properties, storage stability and anti-inflammatory activity in an animal acute inflammation model. Selected NLCs displayed PS of 170.7 nm, EE% of 67.4%, sustained release over 72 h and good stability for 30 days at refrigeration conditions. PA NLCs displayed superior anti-inflammatory activity of 83.9 ± 4.46% compared to PA suspension (40.5 ± 7.03%) and drug-free NLCs (54.7 ± 6.12%). The current work delineates the potential of NLCs for distinctly improved biopharmaceutical performance of PA.

Verapamil hydrochloride loaded solid lipid nanoparticles: Preparation, optimization, characterisation, and assessment of cardioprotective effect in experimental model of myocardial infarcted rats

Verapamil, a calcium channel blocker has poor bioavailability (20-30%) owing to extensive hepatic first-pass metabolism. Hence, the major objective of this research was to improve the oral bioavailability of Verapamil by Solid Lipid Nanoparticles (V-SLNs) using high shear homogenization and ultrasonication technology. A 3² factorial design was employed to statistically optimize the formulation to get minimum particle size with maximum entrapment efficiency. The average particle size was 218 nm and the entrapment efficiency was 80.32%. The V-SLN formulation exhibited biphasic behavior with a rapid release at first, then a steady release (75-80%) up to 24 h following the Korsmeyer Peppas release model. In the Isoproterenol induced myocardial necrosis model, oral administration of V-SLNs positively modulated almost all the studied hemodynamic parameters such as left ventricular end-diastolic pressure, cardiac injury markers, and tissue architecture. The cardioprotective effect was also confirmed with histopathological studies. When compared with free drugs, in-vivo pharmacokinetic studies demonstrated a rise in t_1/2, AUC_0-∞, and Cmax, indicating that bioavailability has improved. These encouraging results demonstrate the promising potential of developed V-SLNs for oral delivery and thereby improve the therapeutic outcome.

Theranostic Nanomedicines for the Treatment of Cardiovascular and Related Diseases: Current Strategies and Future Perspectives

Cardiovascular and related diseases (CVRDs) are among the most prevalent chronic diseases in the 21st century, with a high mortality rate. This review summarizes the various nanomedicines for diagnostic and therapeutic applications in CVRDs, including nanomedicine for angina pectoris, myocarditis, myocardial infarction, pericardial disorder, thrombosis, atherosclerosis, hyperlipidemia, hypertension, pulmonary arterial hypertension and stroke. Theranostic nanomedicines can prolong systemic circulation, escape from the host defense system, and deliver theranostic agents to the targeted site for imaging and therapy at a cellular and molecular level. Presently, discrete non-invasive and non-surgical theranostic methodologies are such an advancement modality capable of targeted diagnosis and therapy and have better efficacy with fewer side effects than conventional medicine. Additionally, we have presented the recent updates on nanomedicine in clinical trials, targeted nanomedicine and its translational challenges for CVRDs. Theranostic nanomedicine acts as a bridge towards CVRDs amelioration and its management.

Nanostructured Lipid Carriers Deliver Resveratrol, Restoring Attenuated Dilation in Small Coronary Arteries, via the AMPK Pathway

Nanostructured lipid carriers (NLCs) are an emerging drug delivery platform for improved drug stability and the bioavailability of antihypertensive drugs and vasoprotective nutraceutical compounds, such as resveratrol (RV). The objective of this study was to ascertain NLCs’ potential to deliver RV and restore attenuated dilator function, using an ex vivo model of acute hypertension. Trimyristin–triolein NLCs were synthesized and loaded with RV. The uptake of RV-NLCs by human coronary artery endothelial cells (HCAECs) maintained their viability and reduced both mitochondrial and cytosolic superoxide levels. Acute pressure elevation in isolated coronary arteries significantly attenuated endothelial-dependent dilator responses, which were reversed following incubation in RV-NLCs, superoxide dismutase or apocynin (p < 0.0001). RV-NLCs demonstrated a five-fold increase in potency in comparison to RV solution. At elevated pressure, in the presence of RV-NLCs, incubation with Nω-nitro-l-arginine (L-NNA) or indomethacin resulted in a significant reduction in the restored dilator component (p < 0.0001), whereas apamin and TRAM-34 had no overall effect. Incubation with the adenosine monophosphate-activated protein kinase (AMPK) inhibitor dorsomorphin significantly attenuated dilator responses (p < 0.001), whereas the SIRT-1 inhibitor EX-527 had no effect. RV-NLCs improved the impaired endothelial-dependent dilation of small coronary arteries, following acute pressure elevation, via NO and downstream COX elements, mediated by AMPK. We suggest that RV-NLCs are an effective delivery modality for improved potency and sustained drug release into the vasculature. Our findings have important implications for the future design and implementation of antihypertensive treatment strategies.

Physicochemical Characteristics and In Vitro Toxicity/Anti-SARS-CoV-2 Activity of Favipiravir Solid Lipid Nanoparticles (SLNs)

The rise of coronavirus (COVID-19) cases worldwide has driven the need to discover and develop novel therapeutics with superior efficacy to treat this disease. This study aims to develop an innovative aerosolized nano-formulation of favipiravir (FPV) as an anti-viral agent against coronavirus infection. The local delivery of FPV nanoparticles (NPs) via nebulization ensures that the drug can reach the site of infection, the lungs. Solid lipid NPs of favipiravir (FPV-SLNs) were formulated utilizing the hot-evaporation method. The physicochemical formulation properties were evaluated using dynamic light scattering (DLS), Fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The aerosol formulation performance was evaluated using an Andersen Cascade Impactor (ACI) at a flow rate of 15 L/min. The FPV-SLN formulation's in vitro anti-viral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was also evaluated using the SARS-CoV-2 pathogen (hCoV-19/Egypt/NRC-3/2020 isolate). The FPV-SLNs' morphology was defined utilizing transmission electron microscopy, showing an irregular shape. By means of FPV-SLNs' nebulization, a fine particle fraction of 60.2 ± 1.7% was produced with 60.2 ± 1.7%, and this finding suggests that FPV-SLNs were appropriate for inhalation drug delivery with a particle size of 537.6 ± 55.72 nm. Importantly, the FPV-SLNs showed anti-viral activity against SARS-CoV-2 with CC50 and IC50 values of 449.6 and 29.9 µg/mL, respectively. This study suggests that inhaled solid lipid NPs of favipiravir could potentially be used against coronavirus.

Lipopolysaccharide Nanosystems for the Enhancement of Oral Bioavailability

Nanosystems that incorporate both polymers and lipids have garnered attention as emerging nanotechnology approach for oral drug delivery. These hybrid systems leverage on the combined properties of polymeric and lipid-based nanocarriers while eliminating their inherent limitations. In view of the safety-related benefits of naturally occurring polymers, we have focused on systems incorporating polysaccharides and derivatives into the hybrid structure. The aim of this review is to evaluate existing biopolymers with specific focus on lipopolysaccharide hybrid systems and their advancement toward enhancing oral drug delivery. Furthermore, we shall identify future research areas that require further exploration toward achieving an optimized hybrid system for easy translation into clinical use. In this review, we have appraised formulations that combined polysaccharides/derivatives with lipids in a single nanocarrier system. These formulations were grouped into lipid-core-polysaccharide-shell systems, polysaccharide-core-lipid-shell systems, self-emulsifying lipopolysaccharide hybrid systems, and hybrid lipopolysaccharide matrix systems. In these systems, we highlighted how the polysaccharide phase enhances the oral absorption of encapsulated bioactives with regard to their function and mechanism. The various lipopolysaccharide designs presented in this review demonstrated significant improvement in pharmacokinetics of bioactives. A multitude of studies found lipopolysaccharide hybrid systems as nascent nanoplatforms for the oral delivery of challenging bioactives due to features that favor gastrointestinal absorption and bioavailability improvement. With future research already geared toward product optimization and scaling up processes, as well as detailed pharmacological and toxicology pre-clinical testing, these versatile systems will have remarkable impact in clinical application.

Glimpse into Cellular Internalization and Intracellular Trafficking of Lipid-Based Nanoparticles in Cancer Cells

Lipid-based nanoparticles as drug delivery carriers have been mainly used for delivery of anti-cancer therapeutic agents. Lipid-based nanoparticles, due to their smaller particle size and similarity to cell membranes, are readily internalized into cancer cells. Interestingly, cancer cells also overexpress receptors for specific ligands including folic acid, hyaluronic acid, and transferrin on their surface. This allows the use of these ligands for surface modification of the lipid-based nanoparticle. These modifications then allow the specific recognition of these ligand-coated nanoparticles by their receptors on cancer cells allowing the targeted gradual intracellular accumulation of the functionalized nanoplatforms. These interactions could eventually enhance the internalization of desired drugs via increasing ligand-receptor mediated cellular uptake of the nanoplatforms. The cellular internalization of the nanoplatforms also varies and depends on their physicochemical properties including particle size, zeta potential, and shape. The cellular uptake is also influenced by the types of ligand internalization pathway utilized by cells such as phagocytosis, macropinocytosis, and multiple endocytosis pathways. In this review, we will classify and discuss lipid based nanoparticles engineered to express specific ligands, and are recognized by their receptors on cancer cell, and their cellular internalization pathways. Moreover, the intracellular fate of nanoparticles decorated with specific ligands and the best internalization pathways (caveolae mediated endocytosis) for safe cargo delivery will be discussed.

A Traffic Light System to Maximize Carbohydrate Cryoprotectants' Effectivity in Nanostructured Lipid Carriers' Lyophilization

Lyophilization is often employed to transform nanoparticle suspensions to stable solid forms. This work proposed Neurofuzzy Logic (NFL) to better understand the lyophilization process of Nanostructured Lipid Carriers’ (NLCs) dispersions and the carbohydrate cryoprotectants’ (CPs) performance in these processes. NLCs were produced by hot homogenization, frozen at different speeds, and lyophilized using several CPs at variable concentrations. NLCs were characterized, and results were expressed as increase in particle size (Δ size), polydispersity (Δ PdI), and zeta potential (Δ ZP) of lyophilized powders (LP) regarding initial dispersions. CPs were classified according to their molecular weights (MW), and the osmolarities (Π) of CPs solutions were also determined. Databases obtained were finally modelled through FormRules^® (Intelligensys Ltd., Kirkwall, Scotland, UK), an NFL software. NFL models revealed that CPs’ MW determines the optimal freezing conditions and CPs’ proportions. The knowledge generated allowed the establishment of a traffic light system intended to successfully select and apply sugars for nanoparticles lyophilization.

Optimized semisolid self-nanoemulsifying system based on glyceryl behenate: A potential nanoplatform for enhancing antitumor activity of raloxifene hydrochloride in MCF-7 human breast cancer cells

Raloxifene hydrochloride (RLX) is a selective estrogen receptor modulator used for treatment and protection against postmenopausal osteoporosis. The drug has been used for protection against breast cancer and more recently, for management of the disease by virtue of its estrogen antagonist action. However, the drug has reduced bioavailability related to low water solubility and first pass metabolism. To surmount these pitfalls, this study aimed at developing and optimizing RLX-loaded semisolid self-nanoemulsifying system (SSNES) with minimized globule size to improve the drug solubility, tumor penetration, and consequently antitumor activity. A simplex lattice mixture design was employed for the formulation and optimization of SSNESs. The mixture components, namely, Compritol® 888 ATO, Tween 20, and polyethylene glycol 200 exhibited significant effect on globule size at P < 0.05. The optimized formulation with globule size of 109.19 ± 2.11 nm showed acceptable thermodynamic stability under stress conditions. Anti-cancer efficacy of the obtained formulation was evaluated in MCF-7 breast cancer cell line. MTT viability assay revealed that RLX-loaded SSNES notably inhibited MCF-7 cell proliferation. Flow cytometry and dual staining with annexin V-FITC/PI were used to assay this anti-proliferative effect and induction of apoptosis, respectively. Cells treated with RLX-loaded SSNES showed significant arrest at G2/M phase associated with significant increase in early/late-stages of apoptotic and necrotic cells. The results exhibited that RLX-loaded SSNES induces apoptosis via the activation of caspase-3 and loss of mitochondrial membrane potential. Accordingly, the proposed SSNES could be regarded as a promising platform for enhancing RLX antitumor activity against breast cancer.

In vitro evaluation of mucoadhesive in situ nanogel of celecoxib for buccal delivery

OBJECTIVE

The research aims for finding the possibility of buccal delivery of celecoxib from an in situ mucoadhesive nanogel, and in vitro evaluation of the gel to evidence the enhanced permeation of drug from buccal mucosa.

MATERIALS AND METHODS

Six formulations of celecoxib loaded NLCs were prepared using stearic acid and oleic acid in different ratio in aqueous solution of poloxamer by emulsion solvent evaporation technique. The physicochemical evaluations of the celecoxib loaded NLC (CeL-NLC) were carried out. The formulation F4 was selected as the best and subjected for FTIR, DSC, PXRD, and surface morphology study. In situ mucoadhesive gel was prepared with F4 in HPC, HPMC and Carbopol 934 gelling systems. The gels were evaluated for their mechanical and rheological properties and in vitro permeation studies through rabbit oral mucosa.

RESULTS

The selected process at high shear homogenization could yield nanoparticles of desired physiochemical properties. The drug and excipients were compatible as disseminated from FTIR study. Transformation of the crystal form to amorphous form of celecoxib was revealed by the solid-state characterization studies. The AFM study unfold the formation of discrete asymmetric nano particles. All mucoadhesive gels found to have good mucoadhesion and rheological property with good in vitro permeation of drug. A comparative study and statistical analysis unveiled that gel containing Carbopol 934 was found to be the best mucoadhesive in situ gel of nano particles of celecoxib with enhanced permeation parameters.

CONCLUSION

Therefore, the above in vitro evaluation of in situ mucoadhesive nano gel proved the potential of the formulation as a promising buccal delivery of celecoxib.

Properties of rapamycin solid lipid nanoparticles for lymphatic access through the lungs & part II: the effect of nanoparticle charge

Aim: Lymphangioleiomyomatosis is characterized by smooth muscle-like cells in the lungs that spread to other organs via lymphatic vessels. Oral rapamycin is restricted by low bioavailability approximately 15%. The aim of the present study is to systematically investigate the effect of inhaled rapamycin solid lipid nanoparticles (Rapa-SLN) surface charge on efficacy and penetration into the lymphatics. Materials & methods: Rapa-SLN formulations with different charge: neutral, positive and negative, were produced and assessed for their physicochemical particle characteristics and efficacy in vitro. Results: Negative Rapa-SLNs were significantly faster at entering the lymphatic endothelium and more potent at inhibiting lymphanigiogenesis compared with neutral and positive Rapa-SLNs. Conclusion: Negative Rapa-SLNs showed efficient lymphatic access and should therefore be investigated further as a treatment for targeting extrapulmonary lymphangioleiomyomatosis.

Omar M, A. Mahmoud H, A. Abou-Taleb H. Nanostructured Lipid Carriers to Mediate Brain Delivery of Temazepam: Design and In Vivo Study

The opposing effect of the blood–brain barrier against the delivery of most drugs warrants the need for an efficient brain targeted drug delivery system for the successful management of neurological disorders. Temazepam-loaded nanostructured lipid carriers (NLCs) have shown possibilities for enhancing bioavailability and brain targeting affinity after oral administration. This study aimed to investigate these properties for insomnia treatment. Temazepam-NLCs were prepared by the solvent injection method and optimized using a 4² full factorial design. The optimum formulation (NLC-1) consisted of; Compritol^® 888 ATO (75 mg), oleic acid (25 mg), and Poloxamer^® 407 (0.3 g), with an entrapment efficiency of 75.2 ± 0.1%. The average size, zeta potential, and polydispersity index were determined to be 306.6 ± 49.6 nm, −10.2 ± 0.3 mV, and 0.09 ± 0.10, respectively. Moreover, an in vitro release study showed that the optimized temazepam NLC-1 formulation had a sustained release profile. Scintigraphy images showed evident improvement in brain uptake for the oral ^99mTc-temazepam NLC-1 formulation versus the ^99mTc-temazepam suspension. Pharmacokinetic data revealed a significant increase in the relative bioavailability of ^99mTc-temazepam NLC-1 formulation (292.7%), compared to that of oral ^99mTc-temazepam suspension. Besides, the NLC formulation exhibited a distinct targeting affinity to rat brain. In conclusion, our results indicate that the developed temazepam NLC formulation can be considered as a potential nanocarrier for brain-mediated drug delivery in the out-patient management of insomnia.

An update on polymer-lipid hybrid systems for improving oral drug delivery

INTRODUCTION

A promising approach that has recently emerged to overcome the complex biobarriers and interrelated challenges associated with oral drug absorption is to combine the benefits of polymeric and lipid-based nanocarriers within one hybrid system. This multifaceted formulation strategy has given rise to a plethora of polymer-lipid hybrid (PLH) systems with varying nanostructures and biological activities, all of which have demonstrated the ability to improve the biopharmaceutical performance of a wide range of challenging therapeutics.

AREAS COVERED

The multitude of polymers that can be combined with lipids to exert a synergistic effect for oral drug delivery have been identified, reviewed and critically evaluated. Specific focus is attributed to preclinical studies performed within the past 5 years that have elucidated the role and mechanism of the polymer phase in altering the oral absorption of encapsulated therapeutics.

EXPERT OPINION

The potential of PLH systems has been clearly identified; however, improved understanding of the structure-activity relationship between PLH systems and oral absorption is fundamental for translating this promising delivery approach into a clinically relevant formulation. Advancing research within this field to identify optimal polymer, lipid combinations and engineering conditions for specific therapeutics are therefore encouraged.