Understanding the Retention of Vaping Additives in the Lungs: Model Lung Surfactant Membrane Perturbation by Vitamin E and Vitamin E Acetate.

Deviations from the normal physicochemical and functional properties of pulmonary surfactants are associated with the incidence of lung injury and other respiratory disorders. This study aims to evaluate the alteration of the 2D molecular organization and morphology of pulmonary surfactant model membranes by the electronic cigarette additives α-tocopherol (vitamin E) and α-tocopherol acetate (vitamin E acetate), which have been associated with lung injury, termed e-cigarette or vaping-use-associated lung injury (EVALI). The model membranes used contained a 7:3 molar ratio of DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) and POPG (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol) to which α-tocopherol and α-tocopherol acetate were added to form mixtures of up to 20 mol % additive. The properties of the neat tocopherol additives and DPPC/POPG (7:3) mixtures with increasing molar proportions of additive were evaluated by surface pressure-area isotherms, excess area calculations, Brewster angle microscopy, grazing incidence X-ray diffraction, X-ray reflectivity, and atomic force microscopy. The addition of either additive alters the essential phase balance of the model pulmonary surfactant membrane by generating a greater proportion of the fluid phase. Despite this net fluidization, both tocopherol additives have space-filling effects on the liquid-expanded and condensed phases, yielding negative excess areas in the liquid-expanded phase and reduced tilt angles in the condensed phase. Both tocopherol additives alter the stability of the fluid phase, pushing the eventual collapse of this phase to higher surface pressures than the model membrane in the absence of an additive.

Modulation of macrophage polarity with carboxymethyl chitin gated hollow mesoporous silica nanoparticles for elevating anti-tumor chemotherapy.

The weak immunity of tumors after chemotherapy could cause tumor metastasis and progression. Therefore, to overcome the dilemma of obvious immune deficiency caused by chemotherapy, a nanosystem (N-IL-12/DOX/α-TOS) consisted of thioketal (TK) bonds linked-hollow mesoporous silica nanoparticles (HMSNs) coated with carboxymethyl chitin (CMCH) by electrostatic interaction, and surface-functionalized glucose-regulated protein 78 binding peptide was prepared for loading doxorubicin (DOX), IL-12 and α-tocopheryl succinate (α-TOS). N-IL-12/DOX/α-TOS displayed a mean size of 275 nm after encapsulated DOX, IL-12 and α-TOS with loading contents of 2.04 × 10-4, 4.01 × 10-2 and 7.12 × 10-2, respectively. The drug-free nanoparticles (NPs) showed good biocompatibility to both 4 T1 cells and RAW264.7 macrophages. N-IL-12/DOX/α-TOS could achieve localized release of IL-12, DOX and α-TOS by pH and H2O2 trigger in the tumor microenvironment (TME). Moreover, the combined therapy by N-IL-12/DOX/α-TOS remarkably elevated the anti-tumor therapeutic efficacy, enhanced immune responses via promoting tumor-associated macrophage (TAM) polarization into tumoricidal M1 phenotypes, and decreased lung metastasis with reduced side effects. N-IL-12/DOX/α-TOS exhibited as a promising strategy for combining chemotherapy and local macrophage modulation-immunotherapy for anti-tumor therapy.

Development of controlled-release antioxidant poly (lactic acid) bilayer active film with different distributions of α-tocopherol and its application in corn oil preservation.

The antioxidant poly (lactic acid) bilayer active films with a different distribution of α-tocopherol (TOC) in two layers (outer layer/inner layer: 0%/6%, 2%/4%, 3%/3%, 4%/2%, 6%/0%) were developed. The effects of TOC distribution on the structural, physicochemical, mechanical, antioxidant and release properties of the films and their application in corn oil packaging were investigated. The different distributions of TOC showed insignificant effects on the color, transparency, tensile strength and oxygen and water vapor barrier properties of the films, but it affected the release behavior of TOC from the films into 95% ethanol and the oxidation degree of corn oil. The film with higher TOC in outer layer showed a slower release rate. The corn oil packaged by the film containing 4% TOC in outer layer and 2% TOC in inner layer exhibited the best oxidative stability. This concept showed a great potential to develop controlled-release active films for food packaging.

Enhancing Ezetimibe Anticancer Activity Through Development of Drug Nano-Micelles Formulations: A Promising Strategy Supported by Molecular Docking.

Background: Ezetimibe, initially recognized as a cholesterol-lowering agent, has recently attracted attention due to its potential anticancer properties. We aimed to explore an innovative approach of enhancing the drug anticancer activity through the development of drug nano-formulations. Materials and Methods: Fifteen different nano-micelles formulations were prepared utilizing D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) and pluronic F127. The prepared formulations were characterized for size, polydispersity index (PDI), zeta potential, and entrapment efficiency (EE). The formulations were morphologically characterized using light and transmission electron microscopies and the drug-binding mode with the active site was investigated using the molecular docking. Cell viability against MCF-7 and T47D was studied. Apoptosis and cell cycle were assessed. Results: The prepared formulations were in the nano-size range (34.01 ± 2.00-278.34 ± 9.11 nm), zeta potential values were very close to zero, and the TPGS-based micelles formulations showed the highest ezetimibe EE (94.03 ± 1.71%). Morphological study illustrated a well-defined, spherical nanoparticles with a uniform size distribution. Molecular docking demonstrated good interaction of ezetimibe with Interleukin-1 Beta Convertase through multiple hydrogen bonding, covalent bond, and hydrophobic interaction. TPGS-based nano-micelle formulation (F5) demonstrated the lowest IC50 against MCF-7 (4.51 µg/mL) and T47D (8.22 µg/mL) cancer cells. When T47D cells were treated with IC50 concentrations of F5, it exhibited significant inhibition with late apoptosis (43.9%), a response comparable to T47D cells treated with an IC50 dose of ezetimibe. Cell cycle analysis revealed that both ezetimibe and F5-treated T47D cells exhibited an increase in the subG1 phase, indicating reduced DNA content and cell death. Conclusion: These findings suggest that F5 could serve as a proficient drug delivery system in augmenting the cytotoxic activity of ezetimibe against breast cancer.

EGFR Targeted Redox Sensitive Chitosan Nanoparticles of Cabazitaxel: Dual-Targeted Cancer Therapy, Lung Distribution, and Targeting Studies by Photoacoustic and Optical Imaging.

In this research, we have modified tocopheryl polyethylene glycol succinate (TPGS) to a redox-sensitive material, denoted as TPGS-SH, and employed the same to develop dual-receptor-targeted nanoparticles of chitosan loaded with cabazitaxel (CZT). The physicochemical properties and morphological characteristics of all nanoparticle formulations were assessed. Dual-receptor targeting redox-sensitive nanoparticles of CZT (F-CTX-CZT-CS-SH-NPs) were developed by a combination of pre- and postconjugation techniques by incorporating synthesized chitosan-folate (F) and TPGS-SH during nanoparticle synthesis and further postconjugated with cetuximab (CTX) for epidermal growth factor receptor (EGFR) targeting. The in vitro release of the drug was seemingly higher in the redox-sensitive buffer media (GSH, 20 mM) compared to that in physiological buffer. However, the extent of cellular uptake of dual-targeted nanoparticles was significantly higher in A549 cells than other control nanoparticles. The IC50 values of F-CTX-CZT-CS-SH-NPs against A549 cells was 0.26 ± 0.12 µg/mL, indicating a 6.3-fold and 60-fold enhancement in cytotoxicity relative to that of dual-receptor targeted, nonredox sensitive nanoparticles and CZT clinical injection, respectively. Furthermore, F-CTX-CZT-CS-SH-NPs demonstrated improved anticancer activity in the benzo(a)pyrene lung cancer model with a higher survival rate. Due to the synergistic combination of enhanced permeability and retention (EPR) effect of small-sized nanoparticles, the innovative and redox sensitive TPGS-SH moiety and the dual folate and EGFR mediated augmented endocytosis have all together significantly enhanced their biodistribution and targeting exclusively to the lung which is evident from their ultrasound/photoacoustic and in vivo imaging system (IVIS) studies.

Solid-liquid equilibria of triacylglycerols and vitamin E mixtures.

Oils and fats are important ingredients for food and pharmaceutical industries. Their main compounds, such as triacylglycerols (TAG), are responsible for determining their physical properties during food storage and consumption. Lipid-rich foods are also sources of minority compounds, which is the case of vitamin E, mainly represented by (±)-α-tocopherol. These compounds can interact with the main lipid molecules in food formulation leading to modification on lipids' physicochemical properties during processes, storage, as well as during digestion, possibly altering their nutritional functionalities, which is the case of vitamin E antioxidant abilities, but also their solubility in the systems. In this case, the study of the phase-behavior between (±)-α-tocopherol and lipid compounds can elucidate these physicochemical changings. Therefore, this work was aimed at determining the solid-liquid equilibrium (SLE) of binary mixtures of TAG (tripalmitin, triolein and tristearin) and (±)-α-tocopherol including the complete description of their phase diagrams. Melting data were evaluated by Differential Scanning Calorimetry, Microscopy, X-Ray Diffraction, and thermodynamic modeling by using Margules, UNIFAC, and COSMO-SAC models. Experimental results showed that systems presented a monotectic-like behavior, with a significant decreasing in TAG melting temperature by the addition of (±)-α-tocopherol. This high affinity and attractive strengths between these molecules were also observed by thermodynamic modeling, whose absolute deviations were below 2 %. Micrographs and X-ray diffraction evidenced the possible formation of solid solutions. Both behaviors are interesting by avoiding phase separation on food in solid and liquid phases, possibly improving the antioxidant role the (±)-α-tocopherol in lipid-base systems.

Antioxidative Effect of Dihydrosphingosine (d18:0) and α-Tocopherol on Tridocosahexaenoin (DHA-TAG).

Sphingoid bases have shown promise as effective antioxidants in fish oils together with α-tocopherol, and the effect has been attributed to products resulting from amino-carbonyl reactions (lipation products) between the sphingoid base amine group and carbonyl compounds from lipid oxidation. In this study, the synergistic effect of dihydrosphingosine (d18:0) and α-tocopherol was studied on pure docosahexaenoic acid (DHA) triacylglycerols with an omics-type liquid- and gas-chromatographic mass spectrometric approach to verify the synergistic effect, to get a comprehensive view on the effect of d18:0 on the oxidation pattern, and to identify the lipation products. The results confirmed that d18:0 rapidly reacts further in the presence of lipid oxidation products and α-tocopherol. α-Tocopherol and d18:0 showed an improved antioxidative effect after 12 h of oxidation, indicating the formation of antioxidants through carbonyl-amine reactions. Imines formed from the carbonyls and d18:0 could be tentatively identified.

Topical Drug Delivery of Concentrated Cabazitaxel in an α-Tocopherol and DMSO Solution.

Topical chemotherapy approaches are relevant for certain skin cancer treatments. This study observes that cabazitaxel (CTX), a broad-spectrum second-generation taxane cytotoxic agent, can be dissolved in α-tocopherol at high concentrations exceeding 100 mg mL-1 . 2D nuclear magnetic resonance (NMR) analysis and molecular dynamics (MD) are used to study this phenomenon. The addition of 30% dimethyl sulfoxide (DMSO) to the α-tocopherol/CTX solution improves its working viscosity and enhances CTX permeation through human skin in vitro (over 5 µg cm-2 within 24 h), while no detectable drug permeates when CTX is dissolved in α-tocopherol alone. In a transepidermal water loss assay, the barrier impairment induced by CTX in 30% DMSO in α-tocopherol, but not in pure DMSO, is reversible 8 h after the formulation removal from the skin surface. Antitumor efficacy of the topical CTX formulation is evaluated in nude mice bearing A431 human squamous carcinoma skin cancer xenografts. With topical application of concentrated CTX solutions (75 mg mL-1 ), tumor growth is significantly suppressed compared to lower concentration groups (0, 25, or 50 mg mL-1 CTX). Taken together, these findings show that topical delivery of CTX using a DMSO and α-tocopherol solvent warrants further study as a treatment for skin malignancies.

Self-assembled low molecular weight chitosan-based cationic micelle for improved water solubility, stability and sustained release of α-tocopherol.

New amphiphilic low molecular weight chitosan-graft-nicotinic acid bearing decyl groups (LCND) was synthesized by two-step reaction and spontaneously assembled into cationic micelle by ultra-sonication method to improve water solubility and photostability properties of α-tocopherol. The chemical structure of LCND was characterized and physical properties of cationic micelle were evaluated. Results displayed that cationic micelle exhibited strong self-assemble ability with nanoscale spherical morphology and showed best loading ability with loading content of 18.50% when the feeding ratio of LCND to α-tocopherol reached 10:3. Meanwhile, the greatly enhanced water solubility, photostability and sustained release behavior of α-tocopherol in cationic micelle were observed. The cumulative release of α-tocopherol in cationic micelle reached up 82.18% within 96 h while free α-tocopherol was completely released within 10 h. Additionally, release kinetics models were also fitted. The LCND cationic micelle could be promising nanocarrier for improving the physicochemical properties of α-tocopherol in food fields.

Construction of multi-program responsive vitamin E succinate-chitosan-histidine nanocarrier and its response strategy in tumor therapy.

Multifunctional drug delivery carriers have emerged as a promising cancer drug delivery strategy. Here, we developed a vitamin E succinate-chitosan-histidine (VCH) multi-program responsive drug carrier. The structure was characterized by FT-IR and 1H NMR spectrum, and the DLS and SEM results showed typical nanostructures. The drug loading content was 21.0 % and the corresponding encapsulation efficiency was 66.6 %. The UV-vis and fluorescence spectra demonstrated the existence of the π-π stacking interaction between DOX and VCH. Drug release experiments implied good pH sensitivity and sustained-release effect. The DOX/VCH nanoparticles could be efficiently taken up by HepG2 cancer cells and the tumor inhibition rate was up to 56.27 %. The DOX/VCH reduced the tumor volume and weight efficiently with a TIR of 45.81 %. The histological analysis results showed that DOX/VCH could effectively inhibit tumor growth and proliferation, and there was no damage to normal organs. VCH nanocarriers could combine the advantages of VES, histidine and chitosan to achieve pH sensitivity and P-gp inhibition, and effectively improve the drug solubility, targeting and lysosomal escape. Through the program response of different micro-environment, the newly developed polymeric micelles could successfully be utilized as a multi-program responsive nanocarrier system for the treatment of cancers.

Synergistic Mechanisms of Interactions between Myricetin or Taxifolin with α-Tocopherol in Oil-in-Water Emulsions.

The antioxidant interactions between α-tocopherol and myricetin in stripped soybean oil-in-water emulsions at pH 4.0 and pH 7.0 were analyzed. At pH 7.0, α-tocopherol (α-TOC):myricetin (MYR) ratios of 2:1 and 1:1 yielded interaction indices of 3.00 and 3.63 for lipid hydroperoxides and 2.44 and 3.00 for hexanal formation, indicating synergism. Myricetin's ability to regenerate oxidized α-tocopherol and slow its degradation was identified as the synergism mechanism. Antagonism was observed at pH 4.0 due to high ferric-reducing activity of myricetin in acidic environment. The interaction between α-tocopherol and taxifolin (TAX) was also investigated due to structural similarities of myricetin and taxifolin. α-Tocopherol and taxifolin combinations exhibited antagonism at both pH 4.0 and pH 7.0. This was associated with taxifolin's inability to recycle α-tocopherol while still increasing the prooxidant activity of iron. The combination of α-tocopherol and myricetin was found to be an excellent antioxidant strategy for oil-in-water emulsions at pH values near neutrality.

Impact of α-tocopherol and EGCG on the oxidative stability of margarine: Exploring the possible synergistic effect mechanism.

Margarine is a typical water-in-oil (W/O) emulsion fat product. Due to the presence of a water-oil interface, the oil oxidation in the emulsion system is the interface reaction, which is much faster than that in bulk oil and shows different oxidation mechanisms. The analysis of Rancimat and electron spin resonance indicated that α-tocopherol and EGCG show synergistic antioxidant effects in the margarine. After 20 days of accelerated oxidation storage, the antioxidant effect of the compound antioxidant (50 mg/kg α-tocopherol + 350 mg/kg EGCG) on the margarine was significantly higher than that of the single antioxidant α-tocopherol and EGCG. Based on the results of antioxidants partitioning, electrochemistry, fluorescence spectroscopy, and the oxidative decomposition of antioxidants, the possible mechanisms of interaction were the promotion of α-tocopherol regeneration by EGCG, and the fact that α-tocopherol and EGCG could act at different stages and positions of oxidation. This work will contribute to studying antioxidant interactions and can provide valuable suggestions for practical production. PRACTICAL APPLICATION: This study aims to improve the oxidative stability of margarine by adding α-tocopherol and epigallocatechin-gallate (EGCG) individually and in blends. The mechanism of compound antioxidant synergistic inhibition of margarine oxidation was analyzed, providing theoretical basis and scientific basis for the research and practical application of natural antioxidant synergistic mechanism.

Experimental design of D-α-tocopherol polyethylene glycol 1000 succinate stabilized bile salt based Nano-vesicles for improved cytotoxicity and bioavailability of colchicine binding site inhibitor Candidates: In Vitro, in silico, and pharmacokinetic studies.

Nowadays, conventional anticancer therapy suffers many pitfalls, including drastic side effects and limited therapeutic efficacy resulting from diminished oral bioavailability. So, in an attempt to enhance their poor solubility and oral bioavailability along with the cytotoxic activity, the developed lead compounds (C1 and C2) were loaded in D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) modified vesicles adopting thin film hydration technique. The formulations of the aforementioned candidates (F1 and F2, respectively) were elected as the optimum formula with desirability values of 0.701 and 0.618, respectively. Furthermore, an outstanding enhancement in the drug's cytotoxic activity against different cancer cell lines (MCF-7, HepG-2, MDA-MB-321, A375, and MGC-803) after being included in the nano-TPGS-modified optimum formula was noticed relative to the unformulated compounds. The formula F1 showed the best cytotoxic activities against HepG-2 with an IC50 = 3 µM. Furthermore, regarding MCF-7, F1 was shown to be the most potent and protective among all the tested formulations with an IC50 = 6 µM. Besides, F1 exerted the best caspase 3/7 activity stimulation (around a 5-folds increase) compared to control in the MCF-7 cell line. Notably, it was disclosedthat both C1 and C2 induced cell cycle arrest at the resting S growth phase. Moreover, C1 and C2 decreased tubulin concentrations by approximately 2-folds and 6-folds, respectively. Meanwhile, the conducted molecular docking studies ensure the eligible binding affinities of the assessed compounds. Besides, MD simulations were performed for 1000 ns to confirm the docking results and study the exact behavior of the target candidates (C1 and C2) toward the CBS.

Dual role of polyglycerol vitamin E succinate in emulsions: An efficient antioxidant emulsifier.

α-Tocopherol, as an oil-soluble vitamin with strong antioxidant activity. It is the most naturally abundant and biologically active form of vitamin E in humans. In this study, a novel emulsifier (PG20-VES) was synthesized by attaching hydrophilic twenty-polyglycerol (PG20) to hydrophobic vitamin E succinate (VES). This emulsifier was shown to have a relatively low critical micelle concentration (CMC = 3.2 µg/mL). The antioxidant activities and emulsification properties of PG20-VES were compared with those of a widely used commercial emulsifier: D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS). PG20-VES exhibited a lower interfacial tension, stronger emulsifying capacity and similar antioxidant property to TPGS. An in vitro digestion study showed that lipid droplets coated by PG20-VES were digested under simulated small intestine conditions. This study showed that PG20-VES is an efficient antioxidant emulsifier, which may have applications in the formulation of bioactive delivery systems in the food, supplement, and pharmaceutical industries.

Changes of molecular mobility of ascorbyl palmitate and α-tocopherol by phospholipid and their effects on antioxidant properties in bulk oil.

Molecular mobility of ascorbyl palmitate and α-tocopherol in the presence of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) were determined by NMR relaxation technique. Synergistic effects of DOPC on the antioxidative capacities of ascorbyl palmitate were evaluated in DPPH radical scavenging assay and bulk oil matrix. NMR relaxation technique can provide information on the mobility of protons. Molecular mobility of two protons in hydroxyl group of ascorbyl palmitate decreased by 85 and 78% in the presence of DOPC compared to those without DOPC. However, proton mobility of α-tocopherol increased by 41% when DOPC was present. DOPC significantly enhanced the DPPH reactivity in medium chain triacylglycerol, while this effect was not observed in α-tocopherol. Mixture of ascorbyl palmitate with DOPC showed synergistic antioxidant properties in corn oil at 60 °C. DOPC may make protons of ascorbyl palmitate in more rigid state, which can enhance hydrogen donating ability and antioxidant properties of ascorbyl palmitate in bulk oils.

Electrochemical and Spectroscopic Characterization of Oxidized Intermediate Forms of Vitamin E.

Vitamin E, a collection of lipophilic phenolic compounds based on chroman-6-ol, has a rich and fascinating oxidative chemistry involving a range of intermediate forms, some of which are proposed to be important in its biological functions. In this review, the available electrochemical and spectroscopic data on these oxidized intermediates are summarized, along with a discussion on how their lifetimes and chemical stability are either typical of similar phenolic and chroman-6-ol derived compounds, or atypical and unique to the specific oxidized isomeric form of vitamin E. The overall electrochemical oxidation mechanism for vitamin E can be summarized as involving the loss of two-electrons and one-proton, although the electron transfer and chemical steps can be controlled to progress along different pathways to prolong the lifetimes of discreet intermediates by modifying the experimental conditions (applied electrochemical potential, aqueous or non-aqueous solvent, and pH). Depending on the environment, the electrochemical reactions can involve single electron transfer (SET), proton-coupled electron transfer (PCET), as well as homogeneous disproportionation and comproportionation steps. The intermediate species produced via chemical or electrochemical oxidation include phenolates, phenol cation radicals, phenoxyl neutral radicals, dications, diamagnetic cations (phenoxeniums) and para-quinone methides. The cation radicals of all the tocopherols are atypically long-lived compared to the cation radicals of other phenols, due to their relatively weak acidity. The diamagnetic cation derived from α-tocopherol is exceptionally long-lived compared to the diamagnetic cations from the other ß-, γ- and δ-isomers of vitamin E and compared with other phenoxenium cations derived from phenolic compounds. In contrast, the lifetime of the phenoxyl radical derived from α-tocopherol, which is considered to be critical in biological reactions, is typical for what is expected for a compound with its structural features. Over longer times via hydrolysis reactions, hydroxy para-quinone hemiketals and quinones can be formed from the oxidized intermediates, which can themselves undergo reduction processes to form intermediate anion radicals and dianions. Methods for generating the oxidized intermediates by chemical, photochemical and electrochemical methods are discussed, along with a summary of how the final products vary depending on the method used for oxidation. Since the intermediates mainly only survive in solution, they are most often monitored using UV-vis spectroscopy, FTIR or Raman spectroscopies, and EPR spectroscopy, with the spectroscopic techniques sometimes combined with fast photoinitiated excitation and time-resolved spectroscopy for detection of short-lived species.

Effect of Ester Moiety on Structural Properties of Binary Mixed Monolayers of Alpha-Tocopherol Derivatives with DPPC.

Phospholipid membranes are ubiquitous components of cells involved in physiological processes; thus, knowledge regarding their interactions with other molecules, including tocopherol ester derivatives, is of great importance. The surface pressure-area isotherms of pure α-tocopherol (Toc) and its derivatives (oxalate (OT), malonate (MT), succinate (ST), and carbo analog (CT)) were studied in Langmuir monolayers in order to evaluate phase formation, compressibility, packing, and ordering. The isotherms and compressibility results indicate that, under pressure, the ester derivatives and CT are able to form two-dimensional liquid-condensed (LC) ordered structures with collapse pressures ranging from 27 mN/m for CT to 44 mN/m for OT. Next, the effect of length of ester moiety on the surface behavior of DPPC/Toc derivatives' binary monolayers at air-water interface was investigated. The average molecular area, elastic modulus, compressibility, and miscibility were calculated as a function of molar fraction of derivatives. Increasing the presence of Toc derivatives in DPPC monolayer induces expansion of isotherms, increased monolayer elasticity, interrupted packing, and lowered ordering in monolayer, leading to its fluidization. Decreasing collapse pressure with increasing molar ratio of derivatives indicates on the miscibility of Toc esters in DPPC monolayer. The interactions between components were analyzed using additivity rule and thermodynamic calculations of excess and total Gibbs energy of mixing. Calculated excess area and Gibbs energy indicated repulsion between components, confirming their partial mixing. In summary, the mechanism of the observed phenomena is mainly connected with interactions of ionized carboxyl groups of ester moieties with DPPC headgroup moieties where formed conformations perturb alignment of acyl chains, resulting in increasing mean area per molecule, leading to disordering and fluidization of mixed monolayer.

Production of α-Tocopherol-Chitosan Nanoparticles by Membrane Emulsification.

α-tocopherol (α-T) has the highest biological activity with respect to the other components of vitamin E; however, conventional formulations of tocopherol often fail to provide satisfactory bioavailability due to its hydrophobic characteristics. In this work, α-tocopherol-loaded nanoparticles based on chitosan were produced by membrane emulsification (ME). A new derivative was obtained by the cross-linking reaction between α-T and chitosan (CH) to preserve its biological activity. ME was selected as a method for nanoparticle production because it is recognized as an innovative and sustainable technology for its uniform-particle production with tuned sizes and high encapsulation efficiency (EE%), and its ability to preserve the functional properties of bioactive ingredients operating in mild conditions. The reaction intermediates and the final product were characterized by 1HNMR, Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC), while the morphological and dimensional properties of the nanoparticles were analyzed using electronic scanning microscopy (SEM) and dynamic light scattering (DLS). The results demonstrated that ME has high potential for the development of α-tocopherol-loaded nanoparticles with a high degree of uniformity (PDI lower than 0.2), an EE of almost 100% and good mechanical strength, resulting in good candidates for the production of functional nanostructured materials for drug delivery. In addition, the chemical bonding between chitosan and α-tocopherol allowed the preservation of the antioxidant properties of the bioactive molecule, as demonstrated by an enhanced antioxidant property and evaluated through in vitro tests, with respect to the starting materials.

Influence of Hydrophobicity in the Hydrophilic Region of Cationic Lipids on Enhancing Nucleic Acid Delivery and Gene Editing.

Intracellular delivery of biomolecules using non-viral vectors critically depends on the vectors' ability to allow the escape and release of the contents from the endosomes. Prior findings demonstrated that aromatic/hydrophobic group-containing amino acids such as phenylalanine (F) and tryptophan (W) destabilize cellular membranes by forming pores in the lipid bilayer. Taking cues from these findings, we have developed four α-tocopherol-based cationic amphiphiles by varying the aromatic/hydrophobic amino acids such as glycine (G), proline (P), phenylalanine (F), and tryptophan (W) as head groups and triazole in the linker region to study their impact on endosomal escape for the enhanced transfection efficacy. The lipids tocopherol-triazole-phenylalanine (TTF) and tocopherol-triazole-tryptophan (TTW) exhibited similar potential to commercial transfecting reagents, Lipofectamine (LF) 3000 and Lipofectamine Messenger Max (LFMM), respectively, in transfecting plasmid DNA and messenger RNA in multiple cultured cell lines. The TTW liposome was also found to be effective in delivering Cas9 mRNA and demonstrated equal efficiency of gene editing AAVS1 locus compared to LFMM in CHO, Neuro-2a, and EA.HY926 cell lines. In this current investigation, it is shown that the synthesized cationic lipids with aromatic hydrophobic R group-containing amino acids are safe, economic, and actually more efficient in nucleic acid delivery and genome-editing applications. These findings can be further explored in the genome-editing approach for treating genetic disorders.

Intraperitoneal administration of nanoparticles containing tocopheryl succinate prevents peritoneal dissemination.

Intraperitoneal administration of anticancer nanoparticles is a rational strategy for preventing peritoneal dissemination of colon cancer due to the prolonged retention of nanoparticles in the abdominal cavity. However, instability of nanoparticles in body fluids causes inefficient retention, reducing its anticancer effects. We have previously developed anticancer nanoparticles containing tocopheryl succinate, which showed high in vivo stability and multifunctional anticancer effects. In the present study, we have demonstrated that peritoneal dissemination derived from colon cancer was prevented by intraperitoneal administration of tocopheryl succinate nanoparticles. The biodistribution of tocopheryl succinate nanoparticles was evaluated using inductively coupled plasma mass spectroscopy and imaging analysis in mice administered quantum dot encapsulated tocopheryl succinate nanoparticles. Intraperitoneal administration of tocopheryl succinate nanoparticles showed longer retention in the abdominal cavity than by its intravenous (i.v.) administration. Moreover, due to effective biodistribution, tumor growth was prevented by intraperitoneal administration of tocopheryl succinate nanoparticles. Furthermore, the anticancer effect was attributed to the inhibition of cancer cell proliferation and improvement of the intraperitoneal microenvironment, such as decrease in the levels of vascular endothelial growth factor A, interleukin 10, and M2-like phenotype of tumor-associated macrophages. Collectively, intraperitoneal administration of tocopheryl succinate nanoparticles is expected to have multifaceted antitumor effects against colon cancer with peritoneal dissemination.